WO2004078272A2

WO2004078272A2 - Dual deck exercise device

Info

Publication number: WO2004078272A2
Application number: PCT/US2004/006140
Authority: WO
Inventors: Gary Piaget; Brent Cristopher; Brian R. Cook; Douglas A. Crawford; Edward L. Flick; Eric D. Golesh; Ben Monette; Randal Potter; Todd Singh; Matt Rauwerdink; Patrick A. Warner; Bradley J. Smith
Original assignee: Nautilus, Inc.
Priority date: 2003-02-28
Filing date: 2004-02-27
Publication date: 2004-09-16
Also published as: HK1205476A1; EP1601419A2; EP2815792B1; WO2004078272A3; EP2815792A2; EP2815792A3; EP1601419B1; EP1601419A4

Abstract

An exercise device employing side-by-side pivotally supported moving surfaces. In one particular example, an exercise device employs a first belt deployed about a front roller and a rear roller and an adjacent second belt deployed about a front roller and a rear roller. The rear of the belts in the area of the rear rollers are pivotally secured and the front of the belts in the area of the front roller are adapted to reciprocate in an up and down motion during use. In some implementations, the moving surfaces include an interconnection structure such that a generally downward movement of one surface is coordinated with a generally upward movement of the other surface. In other implementations, the moving surfaces are operably associated with one or more resistance elements that effect the amount of force required to pivot or actuate the moving surfaces.

Description

DUAL DECK EXERCISE DEVICE

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is related to and claims prior to U.S. Provisional Patent Application No. 60/450,789 entitled "Dual Deck Exercise Device" and filed on February 28, 2003, which is hereby incorporated by reference in its entirety, as if fully described herein.

The present application is related to and incorporates by reference in its entirety, as if fully described herein, the subject matter disclosed in the following U.S. applications:

U.S. Provisional Patent Application No. 60/451,104 entitled "Exercise Device with Treadles" and filed on February 28, 2003;

U.S. Patent Application No. entitled "Exercise Device with Treadles" and filed on February 26, 2004; which is further identified by Dorsey & Whitney LLP Docket No. 2071/US/2 and U.S. Express Mail No. EV 304 883 463 US;

U.S. Provisional Patent Application No. 60/450,890 entitled "System and Method for Controlling an Exercise Apparatus" and filed on February 28, 2003;

U.S. Patent Application No. entitled "Control System and Method for an

Exercise Apparatus" and filed on February 26, 2004; which is further identified by Dorsey & Whitney LLP Docket No. 2076/US/2 and U.S. Express Mail No. EV 447 463 112 US;

U.S. Provisional Patent Application No. entitled "Exercise Device with Treadles" and filed on February 26, 2004; which is further identified by Dorsey & Whitney LLP Docket No. 34005/US and U.S. Express Mail No. EV 447 463 280 US;

U.S. Provisional Patent Application No. entitled "System and Method for

Controlling an Exercise Apparatus" and filed on February 26, 2004; which is further identified by Dorsey & Whitney LLP Docket No. 34006/US and U.S. Express Mail No. EV 447 463 126 US;

U.S. Provisional Patent Application No. entitled "Dual Treadmill Exercise

Device having a Single Rear Roller" and filed on February 26, 2004; which is further identified by Dorsey & Whitney LLP Docket No. 34007/US and U.S. Express Mail No. EV 447 463 293 US;

U.S. Provisional Patent Application No. entitled "Hydraulic Resistance, Arm

Exercise, and Non-Motorized Dual Deck Treadmills" and filed on February 26, 2004; which is further identified by Dorsey & Whitney LLP Docket No. 34103/US and U.S. Express Mail No. EV 447 463 302 US; and

U.S. Design Application No. 29/176,966 entitled "Exercise Device with Treadles" and filed on February 28, 2003.

FIELD OF THE INVENTION

The present invention generally involves the field of exercise devices, and more particularly involves an exercise device including a pair of treadles with moving surfaces provided thereon. BACKGROUND OF THE INVENTION

The health benefits of regular exercise are well lαiown. Many different types of exercise equipment have been developed over time, with various success, to facilitate exercise. Examples of successful classes of exercise equipment include the treadmill and the stair climbing machine. A conventional treadmill typically includes a continuous belt providing a moving surface that a user may walk, jog, or run on. A conventional stair climbing machine typically includes a pair of links adapted to pivot up and down providing a pair of surfaces or pedals that a user may stand on and press up and down to simulate walking up a flight of stairs.

Various embodiments and aspects ofthe present mvention involve an exercise machine that provides side-by-side moving surfaces that are pivotally supported at one end and adapted to pivot up and down at an opposite end. With a device conforming to the present invention, two pivotable moving surfaces are provided in a manner that provides some or all ofthe exercise benefits of using a treadmill with some or all ofthe exercise benefits of using a stair climbing machine. Moreover, an exercise machine conforming to aspects ofthe present invention provides additional health benefits that are not recognized by a treadmill or a stair climbing machine alone. These and numerous other embodiments and aspects ofthe present mvention are discussed in greater detail below.

SUMMARY OF THE INVENTION

According to one embodiment of the invention a first treadle is operably mounted to a frame to pivot with respect to the frame. A first resistance element is mounted between the frame and the first treadle in a mounting position that can be selectively adjusted within a range of mounting positions. The first resistance treadle has a position that is adjusted by the adjustment ofthe mounting position ofthe first resistance element. A similar resistance element may be operably mounted between a second treadle and the frame in order to adjust a position ofthe second treadle with respect to the frame. The resistance elements may be mounted on a continuous adjustment structure such as a lead screw to permit continuous adjustment ofthe resistance elements within their ranges of mounting positions. The lead screw may be operably connected to a motor to rotate the lead screw. As an alternative to the continuous adjustment structure, a discrete adjustment structure such as a pop pin may be used. The attachment point for the resistance element to the treadles may be variable in order to adjust the position ofthe treadles.

According to one embodiment ofthe invention first and second treadles are pivotally mounted to a frame. Each treadle is provided with a continuous tread. Each tread is provided with its own motor producing a driving force for the respective tread. Optionally, each treadle may be provided with a driving roller for transferring the driving force from the corresponding motor to that treadle's continuous tread. Each motor may be controlled separately to drive the two continuous treads at different speeds. Alternatively, the motors may be synchronized through a common control to assure that the two continuous treads are driven at substantially the same speed as each other. According to one embodiment ofthe invention a treadle assembly includes a frame, an upper deck spaced apart from and generally above the frame, a tread that is slidable across a top surface of the upper deck, and a suspension that operably contacts the frame and the upper deck to hold the upper deck in position adjacent to and generally below the tread, the suspension also cushions the upper deck upon deflection ofthe upper deck towards said frame. The suspension may comprise at least one resilient member interposed between said frame and said upper deck, or may include a plurality of resilient bumpers interposed between the frame and the upper deck. At least one rigid bumper may also be provided as part ofthe suspension. Alternatively, the suspension may comprise a plurality of resilient bumpers and a plurality of hard bumpers, wherein the resilient bumpers contact a lower surface ofthe upper deck upon initial deflection ofthe upper deck towards said frame and wherein the hard bumpers are spaced apart from the lower surface of said upper deck upon initial deflection ofthe upper deck towards the frame.

According to another embodiment ofthe present invention a treadle assembly includes a frame, an upper deck spaced apart from and generally above the frame, a tread that is slidable across a top surface ofthe upper deck, and a suspension that operably contacts the frame and the upper deck to hold the upper deck in position adjacent to and generally below the tread, the suspension also cushions the upper deck upon deflection ofthe upper deck towards said frame. The upper deck is cantilevered with respect to the frame, and the suspension system includes at least one resilient member interposed between the frame and the upper deck.

According to one embodiment ofthe present invention a pair of treadles are pivotally attached to a frame at a restrained end ofthe treadles. Each ofthe treadles has a tread portion formed by a top span of a continuous belt. Resistance devices associated with each treadle oppose pivotal movement ofthe treadles in at least one direction. The treadles slope downwardly from the higher restrained ends towards lower free ends. The frame may include an upright. The resistance devices and the treadles may be attached to the upright. At least one ofthe resistance devices may resist pivoting of the corresponding treadle in both directions. An interconnect may be operably associated with each treadle to cause one treadle to rise while the other treadle lowers. The resistance devices would not need to include return spring action if an interconnect is used.

According to one embodiment ofthe present invention a dual deck exercise machine includes a pair of treadles pivotally mounted on a frame. A dependency structure is operably associated with both treadles and mounted to the frame such that when either treadle is pushed down, the other treadle is pushed up. A resistance mechanism is operably associated with the dependency structure to provide resistance to movement ofthe treadles. The dependency structure may be a rocldng arm. The resistance structure may be a rotational brake, an electro-magnetic brake, or a hydraulic mechanism.

According to one embodiment ofthe present invention an exercise machine includes a treadle pivotally mounted to a frame for pivotal movement in a generally vertical plane. A first resistance element, such as a shock, is operably attached at a top end to the frame at first location within a range of attachment locations on the frame. Adjustment ofthe attachment point ofthe resistance element to the frame changes a height ofthe treadle. A lead screw mechanism may be used to attach the resistance mechanism to the frame. A pin may be used to engage the top end ofthe resistance element and an aperture in the frame to attach the top ofthe resistance element to the frame. The pin may be a spring-loaded pop pin. The exercise device may include a second treadle and second resistance element similar to the first treadle and first resistance element. A dependency device may be attached between the first and second treadles to cause one treadle to move up when the other treadles is moved down. The adjustment ofthe two treadles can be independent from each other so that the treadles may be set at different heights.

According to one embodiment of the present invention a dual deck exercise machine includes a pair of treadles connected to a frame by a pair of scissor trusses. Each of the scissor trusses is movable between a lower position and an upper position. A biasing member is attached to each truss to resiliently bias the scissor trusses towards the upper position. A dampener may be associated with each ofthe trusses. A dependency device may be operably associated with each ofthe treadles to cause one treadle to raise as the other treadle is lowered. The treadles may remain parallel to a support surface as the treadles move downwardly. The biasing members can be placed in tension or in compression as the treadles move from the upper position towards the lower position.

According to one embodiment ofthe present invention a dampening device for use on an exercise machine having treadles includes a reservoir containing hydraulic fluid. The reservoir is divided into two chambers by a valve. A plunger is provided in each chamber, and each plunger is associated with a treadle. As one plunger is pushed into its respective chamber by the respective treadle it pushes hydraulic fluid through the valve into the other chamber to push the other plunger and its treadle outward. The valve may be adjustable to produce a varying dampening effect. The plungers may be provided in cylinders that are sealed by a shared cap. The cylinders may be mounted side-by-side and contained within a housing. A passage may be provided in the shared cap to allow for flow of hydraulic fluid between the two chambers. The plungers may be associated with the treadles through a dependency device. A biasing mechanism, such as a spring may be associated with each plunger to urge the corresponding treadles upwards.

According to one embodiment ofthe present invention an exercise device includes a treadle pivotally mounted to a frame for pivotal movement ofthe treadle in a generally vertical plane. A dampener attached between the frame and the treadle resists movement ofthe treadle. A spring attached between the frame and the treadle urges the treadle upward. A similar second treadle may be pivotally mounted to the frame and provided with a dampener and spring. The springs may be elastomeric. The springs may be stretched by a downward movement ofthe treadles, or the springs may be compressed by a downward movement ofthe treadles. The da peners may have adjustable resistance. According to one embodiment ofthe present invention a dual deck exercise machine includes a pair of treadles mounted on a frame. Each o the treadles has front and rear rollers, and a tread extending around the rollers. Each ofthe treadles is associated with a corresponding drive roller mechanism. The drive roller mechanisms may be placed in frictional engagement with the treads. The drive roller mechanisms may also be placed in frictional engagement with one ofthe rollers on each treadle. The drive roller mechanism may be a common drive roller. The common drive roller may be placed in frictional engagement or positive engagement with one ofthe rollers from each treadle. A control mechanism may be provided to control the speed ofthe drive roller mechanism, in order to control the speed at which the treads move.

According to one embodiment ofthe invention an exercise device is provided with a treadle assembly pivotally attached to a frame. The treadle assembly will pivot to a storage position substantially parallel to the upright. Side rails may be pivotally attached to the upright, and may pivot into a storage position. A latching mechanism may be provided to retain the treadle assembly in the storage position. The exercise machine is preferably free standing when in the storage position, with the treadle assembly rotated to an over-center orientation.

According to one embodiment ofthe invention an exercise device is provided with a treadle assembly pivotally attached to a frame. An upright is also pivotally attached to the frame. A side rail is attached to the upright. The side rail will pivot about a side rail pivot into a storage position, and the upright will pivot about an upright pivot into a storage position. A lateral support may be operably attached to the frame to provide lateral support to the exercise device in the storage position. The exercise machine may be free standing on a front end ofthe frame and a bottom portion ofthe upright when adjusted into the storage position.

According to one embodiment ofthe invention an exercise device has a rear base frame with a treadle assembly attached thereto. A front base frame is pivotally attached to a front portion ofthe rear base frame at a base frame pivot. An upright is attached to the front base frame. The rear base frame is pivotal about the base frame pivot between an operational position wherein the front base frame is generally transverse to the upright and a storage position wherein the front base frame is generally parallel with the upright. The treadle assembly may be attached to a rear portion of the rear base frame. The exercise device is free standing on the front base frame with the rear base frame and the upright in a generally vertical orientation when the rear base frame is in the storage position. The rear base frame may be rotated to an over-center orientation in the storage position.

According to one embodiment ofthe present invention an exercise device has a main frame and a housing fixedly attached to the main frame. At least one treadle is attached to the main frame, and the height ofthe housing is at least equal to the height ofthe treadle during operation ofthe treadle. A resistive element may be operationally attached between the treadle and the housing. The housing may be of a single piece construction. A return element may be operationally attached between the treadle and the housing. According to one embodiment ofthe invention a pair of movable belt treadle assemblies are pivotally mounted to a frame. First and second dampening devices are coupled between the frame and the respective treadle assemblies, and first and second biasing devices are coupled between the frame and the respective treadle assemblies. The treadle assemblies may comprise drive rollers that are attached to a motor through a drive shaft and a torque transfer mechanism. The frame may include an upright member to which the treadle assemblies are pivotally mounted. A treadle may be mounded to the upright at a fixed, or variable, pivot point. The dampening devices and biasing devices may be incorporated into first and second unitary devices coupled between the upright and treadle assemblies.

According to another embodiment ofthe present invention, first and second movable belt treadle assemblies are pivotally mounted to a frame. First and second dampening devices are coupled between the frame and their respective treadle assemblies. First and second biasing devices are coupled between the frame and their respective treadle assemblies. First and second movable belt treadle assemblies include belts having upper surfaces for engagement by a user's feet, and a drive mechanism for driving the upper surfaces ofthe belts in a direction away from where the first and second movable treadle assemblies are pivotally mounted to the frame.

According to another embodiment ofthe present invention an exercise device includes a pair of treadle assemblies operably connected to a frame for complementary movement in a generally vertical plane as a user steps on a tread portion of each treadle assembly. Each tread portion is formed by a separate movable belt. The exercise device may include a driver mechanism for moving the movable belts with respect to the treadle assemblies. Optionally, the driver mechanism can drive the belts simultaneously with the treadle assemblies moving in complementary fashion with respect to each other. The treadle assemblies may be locked in a fixed orientation relative to the frame so that the exercise device can function as a treadmill. The movable belts can be locked in a fixed position relative to the treadle assemblies such that the exercise device can function as a stepper.

According to one embodiment ofthe present invention a pair of movable belt treadle assemblies are pivotally mounted to a frame. A rocker arm having a first end and a second end is also pivotally mounted to the frame. A first tie rod is coupled to the first end ofthe rocker arm and the first treadle assembly. A second tie rod is coupled between the second end ofthe rocker arm and the second treadle assembly. Universal joints may be used to couple the tie rods to the rocker arms and the treadle assemblies. The tie rods may be coupled to the treadle assemblies at side frame members provided on the first and second treadle assemblies.

According to another embodiment ofthe present invention first and second treadle assemblies are pivotally mounted to a frame. A rocker arm having a first end and a second end is also pivotally mounted to the frame. A first tie rod couples the first end ofthe rocker arm to the first treadle assembly, and a first biasing device is coupled between the first end ofthe rocker arm and the frame. A second tie rod couples the second end ofthe rocker arm to the second treadle assembly, and a second biasing device is coupled between the second end ofthe rocker arm and the frame.

According to one embodiment ofthe present invention an exercise device includes a pair of treadle assemblies pivotally mounted to a frame. A pair of biasing devices are operably provided between the frame and their respective treadle assemblies for acting against the treadle assemblies with a push-up biasing force. The biasing devices may have fixed biasing characteristics, or variable biasing characteristics. The biasing devices may be coupled directly to a base frame member ofthe frame. The biasing devices may be helical springs. The helical springs may bear against the base frame member at one end and against a flange provided on their respective treadle assemblies at the other end.

According to one embodiment ofthe present invention a pair of treadle assemblies are pivotally mounted to a frame. A brake based dampening assembly is provided that has a first belt and coupled to the first treadle assembly and a second belt coupled to the second treadle assembly. The brake based dampening assembly dampens downward rotation ofthe treadle assemblies. The brake based dampening assembly may include a single continuous dampening belt, a brake, a differential freewheel coupled to the brake, and a pulley system for guiding the continuous dampening belt. Alternatively, the brake based dampening assembly may include a first dampening belt associated with the first treadle assembly, and a second dampening belt associated with the second treadle assembly. The brake based dampening assembly may include first and second dampening belts and first and second brakes. An interconnect device may be included as part ofthe exercise apparatus such that when either ofthe treadle assemblies is pushed down the other treadle assembly is correspondingly pushed up.

According to another embodiment ofthe present invention a pair of treadle assemblies is pivotally mounted to a frame. A single continuous dampening belt is provided with a first end attached to the first treadle assembly and the second end attached to the second treadle assembly. A flywheel is mounted to the frame. A differential freewheel is coupled to the flywheel. A pulley system guides the continuous dampening belt between the first and second ends ofthe continuous dampening belt and includes pulleys attached to the differential freewheel such that movement ofthe treadle assemblies resistably turns the flywheel. The differential freewheel may be eliminated if a differential flywheel is used.

According to one embodiment ofthe present invention first and second treadle assemblies are pivotally mounted to a frame. A first biasing mechanism has a rigid support member disposed on the first treadle assembly and a resilient member coupled to the frame. A second biasing mechanism has a support member disposed on the second treadle assembly and a resilient member coupled to the frame. A flat spring may be coupled to the frame in order to form the first and second biasing mechanisms. A leaf spring may be coupled to the frame in a concave aspect relative to the treadle assemblies to form the biasing mechanisms. A leaf spring may be coupled to the frame to present a convex aspect relative to the treadle assemblies to form the biasing mechanisms. A multiple section torsion spring may be coupled to the frame itself at several locations. The torsion spring sections of the torsion spring form the biasing mechanisms. A flat spring having a first prong and a second prong disposed towards the front ofthe first and second treadle assemblies can form the biasing mechanisms.

According to one embodiment ofthe present invention first and second treadle assemblies are pivotally mounted to a frame. A first cushioning mechanism having a rigid member and a resilient member is disposed between the frame and the first treadle assembly. A second cushioning mechanism having a rigid member and a resilient member is disposed between the frame and the second treadle assembly. The rigid members may comprise rigid protrusions from the treadle assemblies, and the resilient members may include a soft rubber bumper coupled to the frame.

According to one embodiment ofthe present invention a first treadle assembly is provided that has a first belt, a first drive roller and first and second rollers. The first drive roller and a first and second rollers are disposed in a generally inverted triangular arrangement with the first drive roller being at the apex ofthe triangular arrangement. A first belt is disposed around the first drive roller and a first and second rollers, and the first treadle assembly is pivotally mounted to the frame in proximity to the first drive roller. A second treadle assembly similar to the first treadle assembly is also pivotally mounted to the frame proximate to the second drive roller. A motor coupled to the frame may be coupled to a drive shaft through a torque transfer mechanism. The drive shaft may be affixed to the first and second drive rollers to provide a pivot for the first and second treadle assemblies. Dampening devices and biasing devices may be coupled between the frame and the treadle assemblies. A reciprocating linkage may be coupled between the treadle assemblies.

A pair of treadle assemblies are pivotally coupled to a frame. Each ofthe treadle assemblies has at least a front roller and a rear roller. Movable belts are disposed around the front and rear rollers of each treadle assembly. Each treadle assembly has a step area defined on the movable belt between the front roller and the rear roller. A deck is absent from the step areas. Biasing devices may be coupled between the frame and the treadle assemblies. A motor may be provided to move the movable belts around the front and rear rollers. The movable belts may have reinforced edges.

According to another embodiment ofthe present invention a pair of treadle assemblies are pivotally coupled to a frame. Each ofthe treadle assemblies has a front roller and a rear roller with a movable belt disposed around the front and rear rollers. Each treadle assembly includes a deck that has a first user selectable position in proximity to a step area defined between the front roller and the rear roller, and a second user selectable position removed from the step area. Biasing devices may be coupled between the frame and the treadle assemblies. The movable belts may include reinforced edges. The movable belts may be placed in tension between the reinforced edges.

The present invention provides for a protective guard for an exercise apparatus having a first treadle assembly and a second treadle assembly pivotally connected with a base frame. The protective guard helps prevent undesired access to the internal framework ofthe treadle assemblies and the base frame.

In one aspect ofthe present invention, a protective guard for an exercise apparatus having a first treadle assembly and a second treadle assembly includes a base shroud having at least one freadle aperture, a first treadle shroud connected with the first treadle assembly; and a second treadle shroud connected with the second treadle assembly. The first treadle shroud and the second treadle shroud enclose areas between the first treadle assembly, the second treadle assembly, and the base shroud. hi another form, a protective guard for an exercise apparatus having a first treadle assembly and a second treadle assembly includes a base shroud defined by a right side portion, a left side portion, and a rear side portion. The protective guard also includes a first treadle shroud connected with the first treadle assembly, and a second treadle shroud connected with the second treadle assembly.

In yet another form, the protective guard further includes a center shield between the first freadle assembly and the second treadle assembly. The center shield can be pivotally supported on the exercise apparatus by a center drive bracket and a spring.

The features, utilities, and advantages of various embodiments ofthe invention will be apparent from the following more particular description of embodiments ofthe invention as illustrated in the accompanying drawings and defined in the appended claims.

Generally, the invention comprises an exercise machine having dual decks angularly reciprocating about a common axis. The exercise machine may employ two treadles, each capable of independent reciprocating motion. The treadles generally reciprocate about a common axis, either at the front or rear ofthe treadles.

One embodiment ofthe exercise machine may include a locking mechanism. The locking mechanism may lock out or otherwise impede treadle motion. One embodiment ofthe locking mechanism takes the form of a pedal, pivot mechanism, and locking tab. As the pedal is depressed, a bar pivots about the pivot mechanism, moving the locking tab into engagement with a channel formed on the underside ofthe treadle, or optionally simply with the underside ofthe treadle itself. The locking tabs prevent further downward treadle motion.

In another embodiment ofthe locking mechanism, a cam may be attached to the pedal and bar. Downward pedal motion forces the bar along a pivot, driving the cam rotationally upward until it engages the underside ofthe treadle. This results in locking out the treadle motion.

In yet another embodiment of a locking mechanism, the pedal may be omitted and a key attached to one end ofthe bar. The bar may be moved laterally, pushing the key into a slot or receptacle formed on or depending from the underside ofthe treadle. Mating ofthe key and the slot results in restriction of treadle motion.

In some embodiments ofthe dual-deck exercise device, one or more handle bars (or other portion of an upper body structure) may be connected to one or more treadles. The interconnects may take the form of a fixed-length bar or a piston. Where a fixed-length bar is used, the handle bar may include a bar slot along which the top ofthe bar slides when the treadle and/or handle bar is moved. Further, a spring or hinge joint may be located at or near a bend in the handle bar to permit the handle bar to move laterally independent of treadle motion.

In yet other embodiments, the motion of one or more handle bars may partially or fully actuate a corresponding treadle belt motion. For example, the handle bar may be connected to the treadle, or treadle roller, by a one-way bearing or a ratchet and pawl assembly. As the handle bar is moved in a first direction, the bearing or ratchet may force the treadle roller to rotate and the treadle belt to move correspondingly. As the handle bar moves in a second direction, the bearing or ratchet may disengage, permitting free treadle belt movement independent ofthe handle bar. In this manner, the treadle belt is driven in a single direction by handle bar motion. It should be noted the handle bar motion drives only the treadle roller and belt passing therearound, rather than moving the freadle assembly angularly about a pivot point.

Alternately, a bottom end of each handle bar may be received in a slot located along the side of each treadle. In such an embodiment, the handle bars may pivot about a pivot point located between the handle bar top and bottom. Thus, as the handle bars are moved back and forth, the treadles may be driven up and down by the handle bar bottoms moving along the aforementioned slots. The combination of slot and pivot effectively translates the handle bar's lateral motion into vertical motion for the treadle. An interconnect may operatively connect the two treadle axles, moving the treadles in opposite or the same directions.

Some embodiments ofthe dual-deck exercise device may incorporate resistive elements into the handle bar structure to provide or enhance an upper-body workout. For example, a piston or spring may be connected to both a portion ofthe handle bar and an upright or other upper body structure element. As the handle bar portion is driven towards the upper body structure or upright, the piston or spring naturally resists the handle bar motion, forcing a user ofthe exercise device to exert more force to move the handle bar. This, in turn, enhances the user's upper body workout.

Yet other embodiments ofthe dual-deck exercise device may include a height adjustment mechanism capable of changing the rear height ofthe treadles. The treadles may be moved up or down by, for example, turning a threaded screw received in a threaded adjustor attached to a treadle. As the screw turns, the adjustor raises or lowers the attached freadle. Such raising and lowering generally also affects the maximum operating angle achieved between the front and rear of each freadle during operation. As the freadle rear is raised, the maximum operating angle decreases, because the height ofthe treadle rear is raised closer to the maximum operating height ofthe treadle front. In some cases, the treadle rear may be raised sufficiently high that the angle between rear and front ofthe treadle may form a decline, rather than incline.

The dual-deck exercise device may also permit throw adjustment. Generally, "throw" is defined the angle between the lowest and highest points ofthe treadle's vertical motion, as measured from the main frame or exercise device base. Accordingly, this angle may be changed as desired by a user. A throw bar is rotatably attached to a pivot support about a pivot point, and extends in both directions beyond the pivot point, running peφendicular to (and beneath) the longitudinal axis ofthe treadles. One throw adjust per treadle seats along the throw bar. The top of each throw adjust abuts the treadle base.

The throw adjust may be moved along the longitudinal axis ofthe throw bar Generally, the farther away from the pivot point the throw adjust is seated, the greater the vertical distance (translated to angle) traveled by the treadle during operation. Accordingly, adjusting the seating of the throw adjust on the throw bar may vary the treadle's angle of operation.

Finally, some embodiments ofthe dual-deck exercise device may be modular. Modular embodiments may be shipped and/or stored in more compact spaces. For example, the motor, freadles, and drive belt may all be shipped separate from the exercise device frame, and assembled by a user prior to operation. The motor may drive one or more treadles by a drive belt connected to both the motor and a treadle axis or roller. As the motor operates, it turns the drive belt, which in turn rotates the roller and forces a freadle belt overlying the roller to move.

Alternately, the motor may underlie a treadle and be directly connected to the freadle belt by a wheel or other direct-drive device. As the motor operates, the wheel spins beneath the treadle belt, frictionally driving the belt.

Generally speaking, the present invention, in one embodiment, is an exercise machine including a base frame, a first treadle operably coupled to the base frame, and a second treadle operably coupled to the base frame. The first treadle includes a first treadle frame and a first tread surface displaceable relative to the first treadle frame. At least a portion ofthe first treadle frame is displaceable relative to the base frame. Similarly, the second treadle includes a second treadle frame and a second tread surface displaceable relative to the second treadle frame. At least a portion ofthe second treadle frame is displaceable relative to the base frame.

In one embodiment, each fread surface is a set of rollers and each roller is rotationally mounted on an axis supported by the roller's respective freadle frame. The outer circumference of each roller is rotationally displaceable relative to the roller's respective freadle frame and is adapted for direct contact with a user's foot or shoe.

In one embodiment, each tread surface is a tread belt. Each tread belt may be a continuous tread belt (i.e., a fread belt that travels in a continuous circuit about its respective treadle frame as the fread belt displaces) or, each fread belt may be a non-continuous tread belt (i.e., a tread belt that does not travel in a continuous circuit about its respective treadle frame as the tread belt displaces). Where the tread belt is a non-continuous fread belt, the tread belt may have a first end coupled to a first roller and a second end coupled to a second roller. Furthermore, each non-continuous fread belt may be biased so its longitudinal center returns to a starting position after a user's foot or shoe is no longer displacing the belt. In one embodiment, the base frame includes a first frame member and a second frame member and the treadles are pivotally displaceable about an axis that extends between the first and second frame members. In one embodiment, the first and second treadles each further include a roller and the axes ofthe rollers are coaxial with the axis that extends between the first and second frame members. These rollers may be the rear most roller of each treadle, or they may be the forward most roller of each treadle. Also, these rollers may be drive rollers for driving the tread surface of each freadle, or they may be non-powered idler rollers.

In one embodiment, the base frame again includes a first frame member and a second frame member and the treadles are pivotally displaceable about an axis that extends between the first and second frame members. Each freadle further includes a front end roller and a rear end roller, and the axis that extends between first and second frame members intersects the treadle frames at a location forward ofthe rear end roller and rearward ofthe front end roller.

In one embodiment, the first and second frame members each include a slot and the axis, which extends between the first and second frame members and about which the freadles may pivotably displace relative to the base frame, is a rod displaceable along the slots. The slots may be arcuate, and the slope ofthe treadles changes as the rod displaces along the slots. One or both ends of the rod may include a nut or knob for securing the rod in place along the respective slot.

In one embodiment, the base frame further includes guide flanges that extend from the base frame and are offset along the base frame from the axis, which extends between the first and second frame members and about which the treadles may pivotably displace relative to the base frame. Each guide flange includes a slot and first and second positioning elements displaceable within the slot. Each first positioning element is adapted to come into contact with its respective treadle frame to arrest the movement of the treadle in a first direction along the slot. Each second positioning element is adapted to come into contact with its respective treadle frame to arrest the movement ofthe treadle in a second direction along the slot. The slot may be arcuate.

In one embodiment, each treadle further includes a front roller pivotable about a first axis and a rear roller pivotable about a second axis. Furthermore, the axis, which extends between the first and second frame members and about which the treadles are pivotably displaceable relative to the base frame, is perpendicularly offset from a line that runs between the axes ofthe pivotable rollers. The tread surface is a tread belt that displaces about the pivotable rollers.

In a variation ofthe immediately preceding embodiment, each treadle includes a third roller that is coaxial with, and pivotable about, the axis that extends between the first and second frame members and about which the treadles are pivotably displaceable relative to the base frame. Accordingly, the fread belt is displaceable about the three rollers. In yet another variation, each treadle includes a fourth roller pivotable about a third axis that is perpendicularly offset from the line that runs between the axes ofthe front and rear rollers. Accordingly, the fread belt is displaceable about the four rollers. i one embodiment, each treadle further includes a first, a second and a third roller. Each first roller is pivotable about a first axis at the front ofthe respective treadle frame. Each second roller is pivotable about a second axis at the rear ofthe respective freadle frame. Each third roller is pivotable about a third axis perpendicularly offset from the respective treadle frame and fixedly positioned relative to the base frame. Each tread surface is a tread belt that is displaceable about the respective three rollers. Each freadle frame is adapted to displace generally simultaneously rearwardly and downwardly when depressed. Additionally, in one variation of this embodiment, each treadle includes a fourth roller pivotable about a fourth axis perpendicularly offset from the respective treadle frame and fixedly positioned relative to the base frame. Each tread belt is displaceable about the respective four rollers and each freadle frame is adapted to displace generally simultaneously rearwardly and downwardly when depressed.

In one embodiment, the exercise machine further includes pivot links to couple each treadle to the base frame. Each pivot link has a first end pivotally coupled to a freadle about a first axis and a second end pivotally coupled to a portion or extension ofthe base frame about a second axis. For each pivot link, an acute angle exists between the top edge of a pivot link and the adjacent bottom edge of a treadle frame when the freadle has not been depressed. As a treadle is depressed, the angle becomes increasingly acute, and the treadle frame generally simultaneously moves rearward and downward.

In one embodiment, the exercise machine further includes pivot links to couple each treadle to the base frame. Each pivot link has a first end pivotally coupled to a treadle about a first axis and a second end pivotally coupled to a portion or extension ofthe base frame about a second axis. A pivot link may further include a torsion spring acting about the second axis and coupled to the pivot link and the portion or extension ofthe base frame. When a treadle has not been depressed, an obtuse angle exists between the top edge ofthe pivot link and the adjacent top edge ofthe respective treadle frame.

In one embodiment, the exercise machine further includes four bar linkages to couple each treadle to the base frame. Each four bar linkage has a first corner pivotally coupled to a freadle about a first axis and a second corner pivotally coupled to a portion or extension ofthe base frame about a second axis. Each four bar linkage includes upper and lower horizontal members, front and rear vertical members, and a spring. A front end ofthe upper horizontal member is pivotally connected to a top end of the front vertical member about the first axis. A rear end of the lower horizontal member is pivotally connected to a bottom end of the rear vertical member about the second axis. The spring may be between the upper and lower horizontal members and biases the horizontal members apart. When depressed, a treadle frame equipped with the four bar linkage generally simultaneously moves forward and downward.

In one embodiment, each freadle further includes a first swing arm and a second swing arm, and the base frame includes an axle and first and second pulleys and cables. Each first swing arm has a lower end pivotably coupled to the respective treadle and an upper end pivotably coupled to the base frame. Each second swing arm has a lower end pivotably coupled to the respective treadle and an upper end pivotably coupled to the base frame. The first pulley is coaxially mounted on the axle and connected by the first cable to the first freadle. The second pulley is coaxially mounted on the axle and connected by the second cable to the second treadle. Displacement ofthe first treadle causes a generally equal, but opposite displacement ofthe second freadle.

In one embodiment, the exercise machine further includes a rocker arm and a spring, and each freadle further includes a first swing arm and a second swing arm. Each first swing arm has a lower end pivotably coupled to the respective treadle and an upper end pivotably coupled to the base frame. Each second swing arm has a lower end pivotably coupled to the respective freadle and an upper end pivotably coupled to the base frame. The rocker arm is pivotably coupled to the base frame and has a first end operably coupled to the first treadle and a second end operably coupled to the second freadle. The spring biases the treadles back into a non-displaced position after being displaced by a user's foot or shoe. The spring may interact between the base frame and at least one ofthe swing arms. Displacement ofthe first treadle causes a generally equal, but opposite displacement ofthe second treadle.

In one embodiment, the base frame includes first and second vertical posts and a cable routed around a set of sheaves, and each treadle further includes first and second sleeves. The first sleeve is pivotably coupled to the first treadle and slidably displaceable along the first post. The second sleeve is pivotably coupled to the second treadle and slidably displaceable along the second post. The cable interconnects the first and second sleeves such that displacement ofthe first treadle causes a generally equal, but opposite displacement ofthe second treadle.

In one embodiment, the exercise machine further includes a control mechanism and a rocker arm pivotally coupled to the base frame. The rocker arm includes a first end operably coupled to the first treadle and a second end operably coupled to the second treadle. Displacement ofthe ends of the rocker arm may be in a generally vertical plane. Displacement ofthe first treadle causes a generally equal, but opposite displacement ofthe second treadle.

The control mechanism is for limiting the displacement ofthe ends ofthe rocker arm. In one embodiment, the control mechanism includes a rod and first and second cam elements. The rod is rotationally coupled to the base frame. The first cam element is coaxially mounted on the rod and has an outer circumferential surface that is generally parallel to the axis of the first cam element and adapted to contact the first end ofthe rocker arm. Similarly, the second cam element is coaxially mounted on the rod and has an outer circumferential surface that is generally parallel to the axis of the second cam element and adapted to contact the second end ofthe rocker arm. The distance between the axis ofthe each cam element and its outer circumferential surface gradually increases when traveling along the outer circumferential surface from a point where said distance is least to a point where said distance is greatest. In one embodiment, the exercise machine includes a low friction surface located between the first and second treadles. More specifically, in one embodiment, the first freadle may include a first edge, the second treadle may include a second edge adjacent to the first edge, and the low friction surface may be at least a portion of one ofthe edges.

The low friction surface may be a Tollable or rolling type surface (i.e., a low friction surface formed from a set of rollers), a slidable type surface, or a combination of rolling type and sliding type surfaces. The slidable type surface may be TEFLON ™ or nylon, or another low friction type polymer. Also, the slidable type surface may be lubricated.

In embodiment, the exercise machine further includes a third treadle, a portion of which is a low friction surface. The low friction surface may be a rolling type or slidable type surface ofthe types already described. The third freadle may be biased in an upward position. Furthermore, the third treadle may alternatingly track the first and second treadles between a highest freadle displacement point and a point midway between the highest freadle displacement point and a lowest treadle displacement point.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description will refer to the following drawings, wherein like numerals refer to like elements, and wherein:

Fig. 1 is an isometric view of one embodiment of an exercise device, in accordance with the present invention.

Fig. 2 is an isometric view ofthe exercise device shown in Fig. 1 with decorative and protective side panels removed to better illustrate various components ofthe exercise.

Fig. 3 is a left side view ofthe exercise device shown in Fig. 2.

Fig. 4 is a right side view ofthe exercise device shown in Fig. 2.

Fig. 5 is top view of the exercise device shown in Fig. 2.

Fig. 6 is a front view of the exercise device shown in Fig. 2.

Fig. 7 is a rear view of the exercise device shown in Fig. 2.

Fig. 8 is a bottom view ofthe exercise device shown in Fig. 2.

Fig. 9 is a section view taken along line 9 - 9 of Fig. 5.

Fig. 10 is a partial cut away isometric view ofthe exercise device shown in Fig. 2, the view illustrating the rocker arm orientated in a position corresponding with the left freadle in about the lowest position and the right treadle in about the highest position. Fig. 11 is a partial cut away isometric view of the exercise device shown in Fig. 2, the view illustrating the rocker arm orientated in a position corresponding with the left freadle in a position higher than in Fig. 10 and the right treadle in a position lower than in Fig. 10.

Fig. 12 is a partial cut away isometric view of the exercise device shown in Fig. 2, the view illusfrating the rocker arm orientated in a position corresponding with the left freadle about level with the right freadle.

Fig. 13 is a partial cut away isometric view of the exercise device shown in Fig. 2, the view illusfrating the rocker arm orientated in a position corresponding with the left freadle in a position higher than in Fig. 12 and the right freadle in a position lower than in Fig. 12.

Fig. 14 is a partial cut away isometric view of the exercise device shown in Fig. 2, the view illustrating the rocker arm orientated in a position corresponding with the left freadle in a position higher than in Fig. 13 and the right treadle in a position lower than in Fig. 13.

Fig. 15 is a left side view of one embodiment ofthe rocker arm, in accordance with the present invention.

Fig. 16A is an isometric view ofthe exercise device shown in Fig. 2, the exercise device with the left treadle in about the lowest position and the right treadle in about the highest position.

Fig. 16B is a left side view ofthe exercise device in the orientation shown in Fig. 16A and with a representative user.

Fig. 17A is an isometric view ofthe exercise device shown in Fig. 2, the exercise device with the left treadle higher than shown in Fig. 16A, and the right treadle lower than shown in Fig. 16A.

Fig. 17B is a left side view of the exercise device in the orientation shown in Fig. 17A and with a representative user.

Fig. 18A is an isometric view ofthe exercise device shown in Fig. 2, the exercise device with the left and right treadle about level and collectively at about a 10% grade.

Fig. 18B is a left side view of the exercise device in the orientation shown in Fig. 18A and with a representative user.

Fig. 19A is an isometric view ofthe exercise device shown in Fig. 2, the exercise device with the left treadle higher than shown in Fig. 18S, and the right treadle lower than as shown in Fig. 18A.

Fig. 19B is a left side view ofthe exercise device in the orientation shown in Fig. 19A and with a representative user. Fig. 20A is an isometric view ofthe exercise device shown in Fig. 2, the exercise device with the left freadle in about its highest position and the right freadle in about its lowest position.

Fig. 20B is a left side view ofthe exercise device in the orientation shown in Fig. 20A and with a representative user.

Fig. 21 is a partial cut away isometric view of the exercise device shown in Fig. 2, the view illustrating one embodiment of a lock-out mechanism used to prohibit freadle reciprocation, in accordance with the present invention.

Fig. 22 is a side view of the lock-out mechanism in the unengaged position.

Fig. 23 is a side view ofthe lock-out mechanism in the engaged or locked out position.

Fig. 24 is an isometric view of the exercise device of Fig. 2 configured in a shipping position.

Fig. 25 is a partial cut away isometric view ofthe exercise device of Fig. 2 and Fig. 24, the view illusfrating the rocker arm lowered into the shipping position.

Fig. 26 is an isometric view of a base portion of an exercise device with a variable position shock according to one embodiment ofthe present invention.

Fig. 27 is a partial detail view of a lead screw and collar continuous adjustment structure from the base portion of Fig. 26.

Fig. 28 is an isometric view of a variable position shock adjustment assembly.

Fig. 29 is a side plan view of a base portion of an exercise device having a variable position shock according one embodiment ofthe present invention illustrating two positions for the variable position shock.

Fig. 30 is an isometric view of a base portion of a dual fread exercise device, wherein each fread is provided with its own driver roller and motor.

Fig. 31 is an isometric view of a freadle assembly according to one embodiment ofthe present invention.

Fig. 32 is a side elevation view of a freadle assembly according to one embodiment ofthe present invention illusfrating a freadle that uses a soft bumper and a hard bumper to support an upper deck.

Fig. 33 is a side elevation view of a treadle assembly according to one embodiment ofthe present invention illusfrating a freadle that uses multiple soft bumpers to support an upper deck.

Fig. 34 is a side elevation view of a treadle assembly according to one embodiment ofthe present invention illustrating a treadle that uses multiple bumpers of varying heights and hardness to support an upper deck. Fig. 35 is a side elevation view of an exercise device according to the present invention having front pivoting freadles, a side shroud is removed to reveal the pivot connection and motor.

Fig. 36 is a partial isometric view of a dependency structure for interconnecting the movement of two freadles in a dual-deck exercise machine.

Fig. 37 is a side elevation view of an exercise device according to the present invention that includes an adjustable position shock to adjust the grade of a treadle.

Fig. 38 is a detail view of a pop-pin arrangement that can be used in adjusting the location of the adjustable position shock of Fig. 37.

Fig. 39 is a detail view of a lead screw and collar arrangement that can be used in adjusting the location ofthe adjustable position shock of Fig. 37.

Fig. 40A is an isometric view of a base of a dual deck exercise machine that uses a scissor truss structure to support freadles according to one embodiment ofthe present invention.

Fig. 40B is an isometric view of a base of a dual deck exercise machine that uses a scissor truss structure to support freadles and a shock to dampen the reciprocal movement ofthe freadles, according to one embodiment ofthe present invention.

Fig. 41 A is an isometric view of an embodiment of a dual-cylinder dampening device for use in a dual deck exercise machine with a portion of the housing removed to allow viewing ofthe internal structure ofthe dampening device.

Fig. 4 IB is a cross-section view taken along line A-A ofthe dual-cylinder dampening device of Fig. 41.

Fig. 41 C is a cross-section view taken along line A-A ofthe dual-cylinder dampening device of Fig. 41A, with the plungers adjusted to a different position within the cylinders.

Fig. 41D is an exploded view of the dual-cylinder dampening device of Fig. 41A.

Fig. 42 is a partial isometric view of an embodiment of a dual-deck exercise machine according to the present invention that utilizes a Spiraflex® dampening device.

Fig. 43 is a partial isometric view of an embodiment of a dual-deck exercise machine according to the present invention that includes dampening devices and return springs mounted between the treadles and the frame of the exercise machine.

Fig. 44A is a partial side view of a drive roller mechanism and freadle assembly according to one embodiment ofthe present invention.

Fig. 44B is a partial top view ofthe drive roller mechanism and freadle assembly of Fig. 44.

Fig. 45A is an isometric view of an embodiment of a dual deck exercise machine having front mounted treadles according to the present invention.

Fig. 45B is an isometric view ofthe dual deck exercise machine of Fig. 45 folded into a storage position. Fig. 46A is an isometric view of an embodiment of a dual deck exercise machine having front mounted freadles, wherein a base frame extends beneath the treadles according to the present invention.

Fig. 46B is an isometric view ofthe exercise device shown in Fig. 46A adjusted to a folded position.

Fig. 46C is an isometric view ofthe exercise device shown in Fig. 46A adjusted to a free standing storage position.

Fig. 47 A is an isometric view of an exercise device having rear mounted treadles.

Fig. 47B is an isometric view ofthe exercise device shown in Fig. 47A adjusted into a storage position.

Fig. 48A is an isometric view of a housing on an exercise device according to one embodiment ofthe present invention.

Fig. 48B is an additional isometric view of a front portion ofthe housing of Fig. 48A.

Fig. 49 is a side view of an embodiment of an exercise device according to the present invention wherein a pair of movable freadle assemblies are pivotally attached to a front upright portion of a frame, and a combination biasing and dampening device is connected between the treadles and the frame, a shroud portion has been removed to better reveal certain aspects ofthe device.

Fig. 50 is a partial isometric view of an embodiment of an exercise devise according to the present invention illusfrating a rocker arm interconnecting device between a pair of pivotal freadles.

Fig. 51 is a detail isometric view of a rocker arm interconnecting device associated with a pair of biasing devices.

Fig. 52A is an isometric view of a pair of freadle assemblies each having a biasing spring operably provided below the freadle assembly.

Fig. 52B is a side view ofthe freadle assemblies of Fig. 51.

Fig. 53 is an isometric view of a brake in combination with a belt and pulley system for use as a dampener in a dual deck exercise device according to an embodiment ofthe present invention.

Fig. 54 is a partial isometric view of a front end of a base frame of an exercise device that utilizes flat springs as biasing devices to urge treadle assemblies upwards.

Fig. 55 is a partial isometric view ofthe front portion of a dual deck exercise device that uses a flat spring as a biasing device to urge freadle assemblies upwards, and includes dampening devices attached to the treadle assemblies.

Fig. 56 is a partial isometric view ofthe front portion of an exercise device utilizing a concavely mounted leaf spring structure as a biasing device.

Fig. 57 is a partial isometric view of a front portion of an exercise device utilizing a convexly curved leaf spring as a biasing device. Fig. 58 is an isometric view ofthe base portion of an exercise device utilizing a torsion spring as a biasing device.

Fig. 59 is a partial isometric view of a front portion ofthe base frame of an exercise device that utilizes a dual pronged flat spring as a biasing device.

Fig. 60 is an isomefric view of a cushioning mechanism for use in association with a dual freadle exercise device.

Fig. 61 A is an isomefric view of a base portion of a dual deck exercise machine with treadle assemblies that include three rollers.

Fig. 6 IB is a side view ofthe base portion of an exercise device shown in 61 A.

Fig. 62A is a side view of a dual freadle exercise machine according to the present invention, wherein the treadle assemblies do not include a deck portion.

Fig. 62B is an isomefric view of one ofthe freadles from Fig. 62 in use with a user deflecting a movable belt provided on the freadle assembly.

Fig. 62C is a left side view ofthe treadle assembly from the Fig. 62.

Fig. 63 A is a front left-side perspective view ofthe exercise apparatus depicting treadle shroud assemblies separated by a center strip on a base shroud.

Fig. 63B is a front left-side perspective view ofthe exercise apparatus depicting adjacent treadle shroud assemblies.

Fig. 63C is a front left-side perspective view ofthe exercise apparatus depicting treadle shroud assemblies with front side shields.

Fig. 63D is a front right-side perspective view ofthe exercise apparatus shown in Fig. 63.

Figs. 63E - 63X show treadle shroud assemblies in various other views and incorporated in alternative embodiments ofthe present invention.

Fig. 64A is a front left-side perspective view ofthe exercise apparatus depicting treadle shroud assemblies with a flexible shield.

Fig. 64B is a front right-side perspective view ofthe exercise apparatus depicting treadle shroud assemblies with the flexible shield.

Figs. 64C is a cut-away view depicting freadle shroud assemblies with the flexible shield.

Fig. 65 is a front right-side perspective view ofthe exercise apparatus with the base shroud having no front portion and depicting freadle shroud assemblies.

Fig. 66 A is a front left-side perspective view ofthe exercise apparatus depicting freadle shroud assemblies partially enclosing the base shroud.

Fig. 66B is a front left-side perspective view ofthe exercise apparatus depicting freadle shroud assemblies partially enclosing an alternative embodiment ofthe base shroud.

Fig. 66C is a front left-side perspective view ofthe exercise apparatus depicting freadle shroud assemblies partially enclosing an alternative embodiment ofthe base shroud. Fig. 67A is a front left-side perspective view of the exercise apparatus depicting treadle shroud assemblies with accordion-pleated shields.

Fig. 67B is a front right-side perspective view ofthe exercise apparatus depicting freadle shroud assemblies with accordion-pleated shields.

Fig. 67C is a front left-side perspective view ofthe exercise apparatus depicting treadle shroud assemblies with accordion-pleated shields incorporated on an alternative embodiment ofthe present invention.

Fig. 68A is a front left-side perspective view ofthe exercise apparatus depicting accordion- pleated freadle shrouds.

Fig. 68B is a front right-side perspective view ofthe exercise apparatus depicting accordion- pleated freadle shrouds.

Fig. 68C is a front left-side perspective view of an alternative embodiment of the exercise apparatus depicting accordion-pleated freadle shrouds.

Fig. 69A is a front left-side perspective view of the exercise apparatus depicting multi-fold freadle shrouds.

Fig. 69B is a front right-side perspective view ofthe exercise apparatus depicting multi-fold freadle shrouds.

Fig. 70 A is a rear right-side cut-away perspective view ofthe exercise apparatus depicting a center shield supported by a spring.

Fig. 70B is a left-side cut-away view ofthe exercise apparatus of Fig. 70A.

Fig. 70C is a rear right-side cut-away perspective view ofthe center shield of Fig. 70A.

Fig. 71 is a rear left-side perspective view of a freadle assembly depicting an adjustable length treadmill deck.

Fig. 72A depicts a first view of a locking mechanism for use with a dual-deck exercise machine.

Fig. 72B depicts a second view ofthe locking mechanism of Fig. 72A.

Fig. 73 depicts an alternate embodiment of a locking mechanism for use with an exercise machine.

Fig. 74 depicts a third embodiment of a locking mechanism for use with an exercise machine.

Fig. 75 depicts the upper body structure of a dual deck treadmill exercise device and a pair of freadles, with two different interconnects linking the upper body structure to each of the two freadles.

Fig. 76 depicts an embodiment of an exercise device incorporating dual deck freadles driven by a reciprocating pivoting motion of a pair of handle bars.

Fig. 77 depicts a first embodiment of an exercise device incorporating resistive elements in a handle bar structure.

Fig. 78 depicts a second embodiment of an exercise device incorporating resistive elements attached to a handle bar structure. Fig. 79A depicts a side view of a pair of freadles operably connected to a height adjustment mechanism for a freadle.

Fig. 79B depicts an isometric view ofthe height adjustment mechanism of Fig. 79A.

Fig. 79C displays a back view of a treadle attached to a height adjustment mechanism.

Fig. 79D depicts an apparatus for tensioning a drive belt attached to both a height-adjustable freadle, such as that depicted in Figs. 79A-79C, and non-height-adjustable motor.

Fig. 80A depicts freadles ofthe exercise machine operating in an unlocked mode, with the freadle rear in a lowest position afforded by the adjustment mechanism of Figs. 79A-79C.

Fig. 80B displays treadles locked in high position, with the treadle rear in a highest position afforded by an adjustment mechanism of Figs. 79A-79C.

Fig. 81 depicts freadles in both the high position and low position of Figs. 80A and 80B.

Fig. 82 depicts a treadle throw adjustment mechanism.

Fig. 83A depicts two directions of extension for a throw bar used in the throw adjustment mechanism of Fig. 82.

Fig. 83B depicts an isometric view of a throw adjust and throw pull used in the throw adjustment mechanism of Fig. 82.

Fig. 83C depicts the relationship between the position of a throw adjust along the throw bar of Fig. 83 A, the angle of freadle incline, and angle of treadle operation.

Fig. 83D depicts the various settings ofthe throw adjust seating along a throw bar, in accordance with Fig. 83C.

Fig. 83E depicts the relationship between the position of an angle adjust along the angle bar depicted in Fig. 83 A and the starting and stopping angles for a treadle's range of motion.

Fig. 83F depicts the various settings of an angle adjust along the angle bar, in accordance with Fig. 83E.

Fig. 84A depicts an embodiment of a modular freadle and frame configuration.

Fig. 84B depicts the drive gear and motor assembly ofthe modular configuration shown in Fig. 84A, with two treadle assemblies mounted thereto.

Fig. 85 depicts an embodiment of a dual-deck exercise device wherein handle motion actuates treadle motion.

Fig. 86 depicts an alternate embodiment ofthe drive gear and motor assembly shown in Fig. 84.

Fig. 87 is an isomefric view ofthe freadle and base frame portion ofthe exercise machine illustrating a low friction interface, according to one embodiment ofthe invention.

Fig. 88 is an enlarged isometric view ofthe low friction interface illustrated in Fig. 87, wherein the low friction interface is formed by a slick, slidable surface, according to one embodiment of the invention. Fig. 89 is an enlarged isometric view ofthe low friction interface illustrated in Fig. 87, wherein the low friction interface is formed by a set of rollers, according to one embodiment ofthe invention.

Fig. 90 is an isomefric view ofthe treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein the machine is equipped with a third or middle freadle having a low friction surface.

Fig. 91 is an isomefric view of the treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein the fread surface of each treadle includes a set of rollers.

Fig. 92 is an isomefric view ofthe treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein the base frame is coupled with the treadle frame at a point or location between the longitudinal ends of each freadle.

Fig. 93 an isomefric view ofthe treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein a set of triangular frame members are provided to pivotally couple the treadles to the base frame at a location between the ends ofthe freadle.

Fig. 94 is a right side elevation ofthe treadle and base frame portion ofthe exercise machine illustrated in Fig. 93.

Fig. 95 is an isomefric view ofthe treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein an articulated linkage arrangement is utilized to pivotally couple the freadles to the base frame.

Fig. 96 is a left side view ofthe freadle and linkage arrangement illustrated in Fig. 95.

Fig. 97 is an isomefric view of the treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein the treadles have an upper freadle frame with two rollers, a lower freadle frame with two rollers, and a continuous tread belt encircling the frames and rollers to form a frapezoidal configuration when viewed from the side ofthe freadle.

Fig. 98A is a right side view of the treadle illusfrated in Fig. 97 and indicates the trapezoidal configuration formed by the frame, four rollers and continuous tread belt.

Fig. 98B is a right side view of an alternative embodiment ofthe embodiment ofthe invention illusfrated in Fig. 97, namely a freadle with a frame, three rollers, and a continuous fread belt forming a triangular configuration.

Fig. 99A is a right side view ofthe treadle illusfrated in Fig. 97 and indicates the frapezoidal freadle displacing about a pivot point.

Fig. 99B is the same view ofthe treadle illusfrated in Fig. 98B and indicates the triangular freadle displacing about a pivot point.

Fig. 100 is an isometric view ofthe freadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein the freadles have a frapezoidal configuration when viewed from the side, the lower rear roller and the front rear rollers are fixed relative to the base frame, and the freadle may collapse such that the upper treadle frame may move downward and rearward while remaining generally parallel to the lower freadle frame.

Fig. 101 A is a right side view ofthe treadle illusfrated in Fig. 93 and indicates the treadle collapsing.

Fig. 10 IB is a right side view ofthe treadle illusfrated in Fig. 9 IB and indicates the freadle collapsing.

Fig. 102 is an isomefric view ofthe treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein the treadles are coupled to the base frame via pivot link members.

Fig. 103 is an isomefric view of the treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein the freadles are coupled to the base frame of the exercise machine via four bar linkages.

Fig. 104 is a left side elevation ofthe treadle and base frame portion ofthe exercise machine illusfrated in Fig. 103.

Fig. 105 is an isometric view ofthe freadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein each freadle is supported by two swing arms and a cabling system is used to interconnect the left and right freadles and to effect their movement opposite to one another during use ofthe exercise device.

Fig. 106 is an isometric view ofthe exercise machine, according to one embodiment ofthe invention, wherein the exercise machine has a pulley and cable system that provides for opposing motion ofthe left and right treadles relative to one another.

Fig. 107 is an isomefric view ofthe treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein the exercise machine has a rocker arm system that provides for opposing motion ofthe left and right treadles relative to one another.

Fig. 108 is an isomefric view ofthe treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein the exercise machine has a slotted flange structure for adjusting the position of a freadle with respect to the base frame.

Fig. 109 is an isomefric view ofthe treadle and base frame portion ofthe exercise machine, according to one embodiment ofthe invention, wherein a slotted flange structure and a pair of positioning elements are used to adjust the slope of a freadle with respect to the base frame and to limit the angular displacement ofthe treadle about a pivot point.

Fig. 110 is a side elevation ofthe slotted flange structure depicted in Fig. 109.

Fig. 111 is an isomefric view of a portion of an exercise machine including a pair of cam surfaces for controlling the movement of a rocker arm, according to one embodiment ofthe invention.

Fig. 112 is a side elevation ofthe front and rear rollers and the fread belt of an exercise machine employing a non-continuous fread belt, according to one embodiment ofthe invention. Fig. 113 is a partially exploded isometric view ofthe tread belt and rollers illustrated in Fig. 112, according to one embodiment.

Fig. 114 is a fully exploded isomefric view ofthe fread belt and rollers illusfrated in Fig. 112, according to another embodiment.

Fig. 115 is an isomefric view of an exercise device conforming to aspects ofthe present invention, the exercise device having tubular frame members and a resistance element, such as a shock, coupled between a frame member extending transversely between the front of treadle side members and a tubular bar extending between the upright.

DETAILED DESCRIPTION

An exercise device 10 conforming to the present invention may be configured to provide a user with a walking-type exercise, a stepping-type exercise or a climbing-like exercise that is a combination of both walking and stepping. The exercise device generally includes two treadmill-like assemblies 12 (referred to herein as a "freadle" or a "treadle assembly") pivotally connected with a frame 14 so that the freadles may pivot up and down about a common axis 16. Each treadle includes a fread belt 18 that provides a moving surface like a treadmill. In use, a user will walk, jog, or run on the treadles and the freadles will reciprocate about the common axis. The freadles are interconnected so that upward movement of one treadle is accompanied by downward movement of the other treadle. The combination ofthe moving surface ofthe fread belts and the coordinated and interconnected reciprocation ofthe treadles provides an exercise that is similar to climbing on a loose surface, such as walking, jogging, or running up a sand dune where each upward and forward foot movement is accompanied by the foot slipping backward and downward. Extraordinary cardiovascular and other health benefits are achieved by such a climbing-like exercise. Moreover, as will be recognized from the following discussion, the extraordinary health benefits are achieved in a low impact manner.

Fig. 1 is an isomefric view of one example of an exercise device conforming to the present invention. The embodiment ofthe exercise device illusfrated in Fig. 1 includes protective and decorative panels 20, which in some instances obscure the view of some components ofthe exercise device. Fig. 2 is an isometric view the exercise device illusfrated in Fig. 1 with the protective and decorative panels removed to better illustrate all ofthe components ofthe device. The other views of the exercise device shown in Figs. 3 - 8, and others, in most instances, do not include the protective and decorative panels.

Referring to Figs. 1, 2 and others, the exercise device includes a first treadle assembly 12A . and a second treadle assembly 12B, each having a front portion 22 and a rear portion 24. The rear portions ofthe treadle assemblies 12 are pivotally supported at the rear ofthe exercise device 10. The front portions 22 ofthe treadle assemblies are supported above the frame 14, and are configured to reciprocate in a generally up and down manner during use. It is also possible to pivotally support the freadles at the front ofthe exercise device, and support the rear ofthe freadle assemblies above the frame. The freadle assemblies also supports an endless belt or "tread belt" that rotates over a deck 26 and about front 28 and rear 30 rollers to provide either a forward or rearward moving surface.

A user may perform exercise on the device facing toward the front ofthe freadle assemblies (referred to herein as "forward facing use") or may perform exercise on the device facing toward the rear ofthe freadle assemblies (referred to herein as "rearward facing use"). The term "front," "rear," and "right" are used herein with the perspective of a user standing on the device in the forward facing manner the device will be typically used. During any method of use, the user may walk, jog, run, and/or step on the exercise device in a manner where each ofthe user's feet contact one ofthe treadle assemblies. For example, in forward facing use, the user's left foot will typically only contact the left freadle assembly 12A and the user's right foot will typically only contact the right freadle assembly 12B. Alternatively, in rearward facing use, the user's left foot will typically only contact the right freadle assembly 12B and the user's right foot will typically only contact the left freadle assembly 12A.

An exercise device conforming to aspects ofthe invention may be configured to only provide a striding motion or to only provide a stepping motion. For a striding motion, the freadle assemblies are configured to not reciprocate and the endless belts 18 configured to rotate. The term "striding motion" is meant to refer to any typical human striding motion such as walking, jogging and running. For a stepping motion, the freadle assemblies are configured to reciprocate and the endless belts are configured to not rotate about the rollers. The term "stepping motion" is meant to refer to any typical stepping motion, such as when a human walks up stairs, uses a conventional stepper exercise device, walks up a hill, etc.

As mentioned above, the rear 24 of each freadle assembly is pivotally supported at the rear of the exercise device. The front of each treadle assembly is supported above the front portion ofthe exercise device so that the treadle assemblies may pivot upward and downward. When the user steps on a fread belt 18, the associated treadle assembly 12A, 12B (including the belt) will pivot downwardly. As will be described in greater detail below, the treadle assemblies 12 are interconnected such that downward or upward movement of one treadle assembly will cause a respective upward or downward movement ofthe other freadle assembly. Thus, when the user steps on one belt 18, the associated freadle assembly will pivot downwardly while the other freadle assembly will pivot upwardly. With the freadle assemblies configured to move up and down and the tread belts configured to provide a moving striding surface, the user may achieve an exercise movement that encompasses a combination of walking and stepping.

Fig. 2 is a partial cutaway isometric view ofthe embodiment ofthe exercise device 10 shown in Fig. 1. With regard to the left and right freadle assemblies, the tread belt is removed to show the underlying belt platform or "Deck" 26 and the front roller 28 and the rear roller 30. In addition, the belt platform of the left freadle is partially cut away to show the underlying treadle frame components. Referring to Fig. 2 and others, the exercise device includes the underlying main frame 14. The frame provides the general structural support for the moving components and other components of the exercise device. The frame includes a left side member 32, a right side member 34 and a plurality of cross members 36 interconnecting the left side and right side members to provide a unitary base structure. The frame may be set directly on the floor or a may be supported on adjustable legs, cushions, bumpers, or combinations thereof. In the implementation of Fig. 2, adjustable legs 38 are provided at the bottom front left and front right corners ofthe frame.

A left upright 40 is connected with the forward end region of the left side member 32. A right upright 42 is connected with the forward end region ofthe right side member 34. The uprights extend generally upwardly from the frame, with a slight rearward sweep. Handles 44 extend transversely to the top of each upright in a generally T-shaped orientation with the upright. The top ofthe T is the handle and the downwardly extending portion ofthe T is the upright. The handles are arranged generally in the same plane as the respective underlying side members 32, 34. The handles define a first section 46 connected with the uprights, and a second rearwardly section 48 extending angularly oriented with respect to the first section. The handle is adapted for the user to grasp during use ofthe exercise device. A console 50 is supported between the first sections of the handles. The console includes one or more cup holders, an exercise display, and one or more depressions adapted to hold keys, a cell phone, or other personal items. The console is best shown in Figs. 5 and 7.

Fig. 3 is a left side view and Fig. 4 is right side view ofthe exercise device 10 shown in Fig. 2. Fig. 5 is a top view and Fig. 6 is a front view ofthe embodiment ofthe exercise device shown in Fig. 2. Referring to Figs. 2-6, and others, each freadle assembly includes a freadle frame 52 having a left member 54, a right member 56, and a plurality of freadle cross members 58 extending between the left and right members. The front rollers 28 are rotatably supported at the front of each freadle frame and the rear rollers 30 are pivotally supported at the rear of each freadle frame. To adjust the tread belt tension and tracking, the front or rear rollers may be adjustably connected with the freadle frame. In one particular implementation as best shown in Figs. 3 and 4, each front roller is adjustably connected with the front of each respective freadle frame. The front roller includes an axle 60 extending outwardly from both ends of the roller. The outwardly extending ends ofthe axle each define a threaded aperture, 62 and are supported in a channel 64 defined in the forward end ofthe left 54 and right 56 freadle frame side members. The channel defines a forwardly opening end 66. A plate 68 defining a threaded aperture is secured to the front end ofthe left and right members so that the centerline ofthe aperture 70 is in alignment with the forward opening end 66 of the channel 64. A bolt is threaded into the threaded aperture and in engagement with the corresponding threaded aperture in the end ofthe roller axle 60 supported in the channel. Alternatively, a spring is located between the closed rear portion ofthe channel and the pivot axle to bias the pivot axle forwardly. By adjusting one or both ofthe bolts at the ends ofthe axle, the corresponding end ofthe axle may be moved forwardly or rearwardly in the channel to adjust the position ofthe front roller. Adjustment of the front roller can loosen or tighten the fread belt or change the fread belt travel.

The belt decks 26 are located on the top of each treadle frame 52. The deck may be bolted to the freadle frame, may be secured to the frame in combination with a deck cushioning or deck suspension system, or may be loosely mounted on the treadle frame. Each belt deck is located between the respective front 28 and rear 30 rollers of each treadle assembly 12A, 12B. The belt decks are dimensioned to provide a landing platform for most or all ofthe upper run ofthe fread belts 18.

The rear of each freadle assembly is pivotally supported at the rear ofthe frame, and the front of each freadle assembly is supported above the frame by one or more dampening elements 76, an interconnection member 78, or a combination thereof, so that each freadle assembly 12 may pivot up and down with respect to the lower frame. Fig. 7 is a rear view ofthe embodiment ofthe exercise device shown in Fig. 2. Fig. 9 is a section view ofthe rear roller assembly taken along line 9-9 of Fig. 5. Referring to Figs. 5, 7, 9 and others, each freadle assembly is pivotally supported above a rear cross member 80 ofthe main frame 14. In one particular implementation, a drive shaft 82 is rotatably supported above the rear cross member by a left 84A, middle 84B, and right 84C drive bracket, The drive shaft rotatably supports each rear roller. Thus, the left and right rear rollers are rotatably supported about a common drive axis 82, which is also the common rear pivot axis ofthe treadles 12.

A pulley 86 is secured to a portion ofthe drive shaft 82. As shown in Figs. 2, 3, 9 and others, in one particular implementation, the drive pulley 86 is secured to the left end region ofthe drive shaft. However, the drive pulley may be secured to the right end region, or somewhere along the length of the drive shaft between the left and right end regions. A motor 88 is secured to a bottom plate 90 (best shown in the bottom view of Fig. 8) that extends between the right 56 and left 54 side members. A motor shaft 92 extends outwardly from the left side ofthe motor. The motor is mounted so that the motor shaft is generally parallel to the drive shaft 82. A flywheel 94 is secured to the outwardly extending end region ofthe motor shaft. A drive belt 96 is connected between the drive shaft pulley and a motor pulley 98 connected with the motor shaft. Accordingly, the motor is arranged to cause rotation ofthe drive shaft and both rear rollers 30.

A belt speed sensor 100 is operably associated with the fread belt 18 to monitor the speed of the fread belt. In one particular implementation the belt speed sensor is implemented with a reed switch 102 including a magnet 104 and a pick-up 106. The reed switch is operably associated with the drive pulley to produce a belt speed signal. The magnet is imbedded in or connected with the drive pulley 86, and the pick-up is connected with the main frame 14 in an orientation to produce an output pulse each time the magnet rotates past the pick-up. Both the left and right rear rollers 30 are secured to the drive shaft 82. Thus, rotation ofthe drive shaft causes the left and right rear rollers and also the associated endless belts 18 to rotate at, or nearly at, the same pace. It is also possible to provide independent drive shafts for each roller that would be powered by separate motors, with a common motor confrol. In such an instance, motor speed would be coordinated by the controller to cause the fread belts to rotate at or nearly at the same pace. The motor or motors may be configured or commanded through user control to drive the endless belts in a forward direction (i.e., from the left side perspective, counterclockwise about the front and rear rollers) or configured to drive the endless belts in a rearward direction (i.e., from the left side perspective, clockwise about the front and rear rollers).

During use, the tread belt 18 slides over the deck 26 with a particular kinetic friction dependant on various factors including the material ofthe belt and deck and the downward force on the belt, hi some instances, the belt may slightly bind on the deck when the user steps on the belt and increases the kinetic friction between the belt and deck. Besides the force imparted by the motor 88 to rotate the belts, the flywheel 94 secured to the motor shaft has an angular momentum force component that helps to overcome the increased kinetic friction and help provide uniform fread belt movement. In one particular implementation, the deck is a 3/8" thick MDF with an electron beam cured paint coating. Further, the belt is a polyester weave base with a PVC top.

Certain embodiments ofthe present invention may include a resistance element 76 operably connected with the treadles. As used herein the term "resistance element" is meant to include any type of device, structure, member, assembly, and configuration that resists the pivotal movement of the freadles. The resistance provided by the resistance element may be constant, variable, and/or adjustable. Moreover, the resistance may be a function of load, of time, of heat, or of other factors. Such a resistance element may provide other functions, such as dampening the downward, upward, or both movement ofthe freadles. The resistance element may also impart a return force on the freadles such that if the treadle is in a lower position, the resistance element will impart a return force to move the freadle upward, or ifthe freadle is in an upper position, the resistance element will impart a return force to move the freadle downward. The term "shock" or "dampening element" is sometimes used herein to refer to a resistance element, or to a spring (return force) element, or a dampening element that may or may not include a spring (return) force.

In one particular configuration ofthe exercise device, a resistance element 76 extends between each treadle assembly 12 and the frame 14 to support the front ofthe treadle assemblies and to resist the downward movement of each freadle. The resistance element or elements may be arranged at various locations between freadle frame and the main frame. In the embodiments shown in Figs. 1-7, and others, the resistance elements include a first 108 and a second 110 shock. The shock both resists and dampens the movement ofthe treadles. More particularly, the first or left shock 108 extends between the left or outer frame member 54 of the left treadle assembly and the left upright frame member 40. The second shock 110 extends between the right or outer frame member 56 ofthe right freadle assembly and the right upright frame member 42. Fig. 26 illustrates an alternative embodiment ofthe present invention wherein shocks extend between the outer frame members of each treadle assembly and a portion ofthe frame below the freadle assembly. In another alternative, the shocks may be connected to the front ofthe freadles (See Fig. 40) between the inner and outer treadle frame members.

In one particular implementation, the shock (108, 110) is a fluid-type or air-type dampening device and is not combined internally or externally with a return spring. As such, when a user's foot lands on the front of a treadle, the shock dampens and resists the downward force ofthe footfall to provide cushioning for the user's foot, leg and various leg joints such as the ankle and knee, hi some configurations, the resistance device may also be adjusted to decrease or increase the downward stroke length of a treadle. The shock may be provided with a user adjustable dampening collar, which when rotated causes the dampening force ofthe shock to either increase or decrease to fit any particular user's needs. One particular shock that may be used in an exercise device conforming to the present invention is shown and described in U.S. Patent 5,762,587 titled "Exercise Machine With Adjustable-Resistance, Hydraulic Cylinder," the disclosure of which is hereby incorporated by reference in its entirety.

Generally, the shock includes a cylinder filled with hydraulic fluid. A piston rod extends outwardly from the cylinder. Within the cylinder, a piston is connected with the piston rod. The piston defines at least one orifice through which hydraulic fluid may flow, and also includes a check valve. The piston subdivides the cylinder into two fluid filled chambers. During actuation ofthe shock, the piston either moves up or down in the cylinder. In downward movement or extension of the shock, the fluid flows through the orifice at a rate governed partially by the number of orifices and the size ofthe orifices. In upward movement or compression of the shock, the fluid flows through the check valve. The collar is operably connected with a plate associated with the orifice or orifices. Rotation ofthe collar, will expose or cover orifices for fluid flow and thus reduce or increase the dampening force ofthe shock. Alternatively, the dampening resistance collar is connected with a tapered plunger directed into an orifice between the hydraulic chambers ofthe shock. The depth of the plunger will govern, in part, the resistance ofthe shock. Preferably, the return spring shown in Fig. 4 ofthe '587 patent is removed.

Another particular shock that may be used in an exercise device conforming to the present invention is shown and described in U.S. Patent 5,622,527 titled "Independent action stepper" and issued on April 22, 1997, the disclosure of which is hereby incorporated by reference in its entirety. The shock may be used with the spring 252 shown in Fig. 10 ofthe '527 patent. The spring provides a return force that moves or returns the treadles upward after they are pressed downward. Preferably, however, the spring 252 is removed. As such, in one implementation ofthe present invention, the shock only provides a resistance and does not provide a return force. In an embodiment that does not employ a spring, the shock may be arranged to provide a resistance in the range of 47 KgF to 103 KgF. Alternative resistance elements are discussed in more detail below.

Figs. 10-14 are partial isometric views ofthe exercise device particularly illusfrating the treadle interconnection structure 78. Each of Figs. 10-14 show the interconnection structure in a different position. Fig. 15 is a side view ofthe freadle interconnection structure in the same position as is shown in Fig. 12. Figs. 16(A,B)-20(A,B) are isomefric views ofthe exercise device corresponding with the views shown in Figs. 10-14. In the particular implementation ofthe interconnection structure illustrated in Figs. 10-15 and others, the interconnection structure includes a rocker arm assembly 112 pivotally supported on a rocker cross member 114 extending between the left 32 and right 34 side members ofthe frame. The rocker arm assembly is operably connected with each freadle assembly 12. As best shown in Fig. 15, the rocker cross member defines a U-shaped cross section. Each upstanding portion ofthe U defines a key way 116, (see, e.g., Figs. 14 and 25). The top ofthe key way defines a pivot aperture 116. The rocker arm includes a rocker pivot axle 120 that is supported in and extends between each pivot aperture to pivotally support the rocker arm. As discussed in more detail below, the key way provides a way for the interconnect structure to be moved between a "shipping" position and a "use" position.

The left and right outer portions ofthe rocker arm include a first or left lower pivot pin 122 and a second or right lower pivot pin 124, respectively. A generally L-shaped bracket 126 supporting a first upper pivot pin 128 extends downwardly from the inner or right side member 56 ofthe left freadle 12A so that the upper pivot pin is supported generally parallel, below, and outwardly ofthe inner side member. A second generally L-shaped bracket 128 supporting a second upper pivot pin 130 extends downwardly from the inner or left side tube 54 ofthe right treadle assembly 128 so that the upper pivot pin is supported generally parallel, below, and outwardly ofthe inner side member.

A first rod 134 is connected between the left upper 128 and lower 122 pivot pins. A second rod 136 is connected between the right upper 130 and lower 124 pivot pins. The rods couple the freadles to the rocker arm. In one particular implementation, each rod (134, 136) defines a turnbuckle with an adjustable length. The turnbuckles are connected in a ball joint 138 configuration with the upper and lower pivot pins. A turnbuckle defines an upper and a lower threaded sleeve 140. Each threaded sleeve defines a circular cavity with opposing ends to support a pivot ball. The pivot pins are supported in the pivot balls. A rod defines opposing threaded ends 142, each supported in a corresponding threaded sleeve. As will be discussed in more detail below, the treadle assemblies 12 may be locked-out so as to not pivot about the rear axis 16. When locked out, the belts 18 ofthe treadle assemblies collectively provide an effectively single non-pivoting treadmill-like striding surface. By adjusting the length of one or both ofthe turnbuckles 134, 136 through rotation ofthe rod 142 during assembly ofthe exercise device or afterwards, the level ofthe two freadles may be precisely aligned so that the two freadles belts, in combination, provide a level striding surface in the lock-out position.

The interconnection structure 78 (e.g., the rocker arm assembly) interconnects the left treadle with the right freadle in such a manner that when one freadle, (e.g., the left treadle) is pivoted about the rear pivot axis 16 downwardly then upwardly, the other treadle (e.g., the right freadle) is pivoted upwardly then downwardly, respectively, about the rear pivot axis in coordination. Thus, the two treadles are interconnected in a manner to provide a stepping motion where the downward movement of one treadle is accompanied by the upward movement ofthe other freadle and vice versa. During such a stepping motion, whether alone or in combination with a striding motion, the rocker arm 112 pivots or teeters about the rocker axis 120.

Referring now to Figs. 10-14 and 16(A,B)-20(A,B), the climbing-like exercise provided by the motion ofthe exercise device 10 is described in more detail. A representative user (hereinafter the "user") is shown in forward facing use in Figs. 16B-20B. The user is walking forward and the device is configured for climbing-type use, i.e., so the treadles reciprocate. The foot motion shown is representative of only one user. In some instances, the freadles 12 may not move between the uppermost and lower-most position, but rather points in between. In some instances, the user may have a shorter or longer stride than that shown. In some instances, a user may walk backward, or may face backward, or may face backward and walk backward. *

In Figs. 10 and 16A, the left freadle 12A is in a lower position and the right freadle 12B is in an upper position. Referring to Figs. 10 and 14, the left side of the rocker arm 118 is pivoted downwardly and the right side ofthe rocker arm is pivoted upwardly. In Fig. 16B, the user is shown with his right foot forward and on the front portion ofthe right tread belt. In the orientation ofthe user shown in Fig. 16B, during forward facing climbing-type use, the user's left leg will be extended downwardly and rearwardly with the majority ofthe user's weight on the left freadle. The user's right leg will be bent at the knee and extended forwardly so that the user's right foot is beginning to press down on the right treadle. From the orientation shown in Fig. 16B, the user will transition his weight to a balance between the right leg and the left leg, and begin to press downwardly with his right leg to force the right freadle downwardly. Due to the movement ofthe belts, both feet will move rearwardly from the position shown in Fig. 16B.

Figs. 11, 17A, and 17B show the orientation of the device 10 and the user in a position after that shown in Figs. 10, 16 A, and 16B. The right freadle 12B is being pressed downwardly, which, via the rocker interconnection structure 78, causes the left treadle 12A to begin to rise. The user's right foot has moved rearwardly and downwardly from the position shown in Fig. 16B. The user's left foot has moved rearwardly and upwardly fro" "he position shown in Fig. 16B.

Figs. 12, 18A, and 18B show the right freadle 12B about midway through its upward sfroke, and the left freadle 12A about midway through its downward stroke. As such, the treadle assemblies are nearly at the same level above the frame 14 and the endless belts 18 are also at the same level. As shown in Fig. 18B, the user's right foot and leg have moved rearwardly and downwardly from the position shown in Fig. 17B. The user's left foot has moved rearwardly and upwardly from the position shown in Fig. 16B. At this point, the user has begun to lift the left foot from the left fread belt in taking a forward stride; thus, the left heel is lifted and the user has rolled onto the ball ofthe left foot. Typically, more weight will now be on the right treadle than the left freadle.

After the orientation shown in Figs. 12, 18A, and 18B, the right treadle 12B continues it downward movement and the left treadle 12A continues its upward movement to the orientation ofthe device as shown in Figs. 13, 19A, and 19B. In Figs. 13, 19A, and 19B, the left treadle is higher than the right freadle, and the rocker arm 112 is pivoted about the rocker pivot axis 120 such that its right side is lower than its left side. In this position, the user's right leg continues to move rearward and downward. The user has lifted the right leg off the left freadle and is moving it forward. At about the upper position ofthe left treadle, the user will step down with his left foot on the front portion ofthe treadle belt. All ofthe user's weight is on the right freadle until the user places his left foot on the left treadle. The user continues to provide a downward force on the right freadle forcing the left treadle up.

Figs. 14, 20 A, and 20B illustrate the right treadle 12B in about its lowest position, and show the left freadle 12A in about its highest position. At this point, the user has stepped down on the front 22 ofthe left freadle and has begun pressing downward with the left leg. The user is also beginning to lift the right leg. The downward force on the left freadle will be transferred through the interconnection structure 78 to the right freadle to cause the right freadle to begin to rise.

Figs. 16(A,B)-20(A,B) represent half a cycle ofthe reciprocating motion ofthe freadles, i.e., the movement ofthe left freadle from a lower position to an upper position and the movement ofthe right freadle from an upper position to a lower position. A complete climbing-type exercise cycle is represented by the movement of one freadle from some position and back to the same position in a manner that includes a full upward sfroke ofthe freadle (from the lower position to the upper position) and a full downward sfroke ofthe freadle (from the upper position to the lower position). For example, a step cycle referenced from the lower position ofthe left freadle (the upper position ofthe right treadle) will include the movement ofthe left treadle upward from the lower position to the upper position and then downward back to its lower position. In another example, a step cycle referenced from the mid-point position ofthe left freadle (see Fig. 18) will include the upward movement ofthe freadle to the upper position, the downward movement from the upper position, past the mid-point position and to the lower position, and the upward movement back to the mid-point position. The order of upward and downward treadle movements does not matter. Thus, the upward movement may be followed by the downward movement or the downward movement may be followed by the upward movement.

Referring to Fig. 10 and others, in one particular configuration, the exercise device includes a step sensor 144, which provides an output pulse corresponding with each downward sfroke of each treadle. The step sensor is implemented with a second reed switch 146 including a magnet 148 and a pick-up 150. The magnet is connected to the end of a bracket 152 that extends upwardly from the rocker arm 112. The bracket orients the magnet so that it swings back and forth past the pick-up, which is mounted on a bracket connected with the rocker cross member 114. The reed switch 146 triggers an output pulse each time the magnet 148 passes the pick-up 150. Thus, the reed switch fransmits an output pulse when the right treadle 12B is moving downward, which corresponds with the magnet passing downwardly past the pick-up, and the reed switch also transmits an output pulse when the left treadle 12A is moving upward, which corresponds with the movement to the magnet upwardly past the pick-up. The output pulses are used to monitor the oscillation, speed, depth of stroke, and sfroke count ofthe freadles as they move up and down during use. The output pulses, alone or in combination with the belt speed signal, may be used to provide an exercise frequency display and may be used in various exercise related calculations, such as in determining the user's calorie burn rate.

As best shown in Figs. 3, 7, and 14-20, in one particular implementation, each treadle includes a bottom-out assembly 154. The bottom-out assembly includes a generally V-shaped bracket 156 interconnected between the inside and outside members ofthe freadle frame. The vertex region ofthe V-shaped bracket is oriented downwardly and generally defines a flat mounting surface 158. A block 160 is fixed to the lower downwardly facing portion ofthe mounting surface. When the exercise device is assembled it is preferable to arrange the freadles by way ofthe turnbuckles (134, 136) so that the block 160 is maintained slightly above the underlying lock-out cross member 162 when the treadle is in its lowest position. A bumper 164 may be fixed to the cross member 162 to cushion the freadle should it bottom out. In one example, the block is fabricated with a hard, non- flexible, plastic. The block may also be fabricated with a solid or flexible resilient polymer material, hi a flexible resilient form, the block will provide some cushioning should the block bottom-out on the lock-out cross member during use.

As mentioned above, the exercise device 10 may be configured in a "lock-out" position where the treadle assemblies do not pivot upward and downward. In one particular lock-out orientation, the treadle assemblies are pivotally fixed so that the fread belts are level and at about a 10% grade with respect to the rear ofthe exercise device. Thus, in a forward facing use, the user may simulate striding uphill, and in a rearward facing use the user may simulate striding downhill.

Fig. 21 is a partial isomefric view ofthe left front of the exercise device with the left upright removed to better illustrate one particular lock-out mechanism 166, in accordance with the present invention. Fig. 22 is a partial side view ofthe left front portion ofthe exercise device with the lockout mechanism 166 in the unengaged position. Fig. 23 is a partial side view ofthe left front portion of the exercise device with the lock-out mechanism in the engaged position. The lock-out mechanism includes a generally T-shaped lever arm 168 with a lower portion 170 and an upper portion 172. The lower portion ofthe lever arm/latch 168 is pivotally connected with a lever bracket 174 extending rearwardly from the front cross member 176. The upper portion ofthe latch 168 is pivotally connected with a left 178 and a right 180 latch offset link about a common pivot axis 182. The left offset link is connected with a left slide bracket 184 that is slidably supported on a left guide bracket 186. The right offset link is connected with a right slide bracket 188 that is slidably supported on a second or right guide bracket 190. The two guide brackets are mounted on the upper surface ofthe lock-out cross member 162 in such a manner that each guide bracket defines a guideway extending generally in a direction between the front and rear ofthe exercise device. In one implementation, each guideway comprises a pair of upwardly extending sidewalls 192. The slide brackets define downwardly extending sidewalls 194 separated by a distance slightly greater then the distance between the upwardly extending sidewalls ofthe guide brackets. An elongate longitudinally extending slot 196 is defined in each ofthe guideway sidewalls. The slots are adapted to receive guide pins 198 that extend inwardly from the downwardly extending sidewalls of the slide brackets. The slide brackets are thus adapted to move forwardly and rearwardly about the guideways. The fore and aft range ofthe slide brackets is governed by the length ofthe channels and the fore and aft separation ofthe guide pins. The lock-out bumper 164 is connected with the top of each ofthe slide brackets.

As best shown in Fig. 21, an upwardly extending face plate 200 defines an upwardly extending slot 202 adapted to receive the lever arm 168. The bottom ofthe slot defines an offset slot 204 portion with a short downwardly extending keeper flange 206. In the non-lock out position (see Fig. 22) the lever arm is maintained in the offset slot portion and held in place by the keeper flange. To lock-out the freadles, the lever arm is first pressed downwardly to disengage it from the keeper flange, and then it is moved toward the right or away from the offset slot. Next the lever arm is raised upward in the slot. The upward motion causes the lever arm to pivot upwardly about the pivotal connection to the lever bracket 174. This upward pivoting motion is accompanied by a generally rearward motion ofthe upper portion 172 ofthe latch that causes the offset links 178, 180 to slide in the slide brackets 184, 186 and bumpers rearwardly along the guideways. A lever spring (not shown) may be connected between the lock-out assembly and one ofthe cross members to assist the user in moving the lock-out assembly into the "locked-out" position.

Before actuating the lock-out mechanism 162, the freadle assemblies are oriented generally level with each other, which causes the stop blocks 160 underhanging each freadle to be oriented at about the same vertical location. In this position, the lock-out assembly is moved rearwardly so that the bumpers 164 are moved rearwardly into engagement with the stop blocks 160. The rearward face of the bumpers may be tapered. As such, the bumpers may be wedged under the stop blocks to configure the exercise device in the "lock-out" position with the freadles prohibited from up and down motion.

To mount the device, the user may simply step up onto the freadles 12 and begin exercising. Alternatively, the user may step onto a foot platform 208 extending outwardly from the side of each treadle assembly 12. As shown in Fig. 1, each platform defines a flat mounting surface 210 generally level with the adjacent treadle assembly and upper belt surface. The mounting surface may be Icnurled or have other similar type features to enhance the fraction between the user's shoe or foot and the mounting surface. As shown in Fig. 2 and others, each platform is secured to an outwardly extending platform bracket 212. The platform bracket is secured to and extends outwardly from the left and right freadle frame members 54, 56. Fig. 27 illustrates an exercise device employing an alternative rear mounting platform 214, in accordance with the present invention. The rear mounting platform includes a single foot platform extending rearwardly from and at about the same level as the rear portion ofthe freadles 12.

To facilitate shipping the exercise device, some implementations ofthe exercise device may be configured so that the freadles 12 may be lowered into a shipping position from which the freadles may be easily moved upward and snapped into the operating position. Fig. 24 is an isometric view of the exercise device lowered into the shipping position, and with the left 40 and right 42 uprights and console 50 disconnected from the exercise device 10. Fig. 25 is a partial isomefric view ofthe rocker arm assembly 112 lowered into the shipping position.

For an exercise device configured so that it may be lowered into the shipping position, the rocker arm pivot axle 120 is spring loaded so that it may be lowered in the key ways 116. As best shown in Fig. 15, each end ofthe rocker arm pivot axle includes an end cap 216. Each end cap includes a circumferential flange 218 of a diameter greater than any portion ofthe key way 116 including the pivot aperture 118. The end cap also defines a collar 220 arranged inwardly ofthe flange 218. The collar is of a diameter greater than the downwardly extending key way slot, but less than the diameter ofthe pivot aperture. The collar supports the rocker assembly 112 in the pivot aperture during use. To lower the rocker assembly, the end caps 216 are extended outwardly from the rocker arm. The collar is supported on a lesser diameter rod (the pivot axle) that is exposed when the cap is pulled out. The pivot axle is dropped down in the key ways, as shown in Fig. 25. Lowering the rocker arm causes the freadles 12 to pivot downwardly until the stop blocks 160 bottom out on the lock-out cross member 162. To configure the exercise device in its exercise or "use" orientation, the rocker assembly is lifted up, such as by lifting the front ofthe freadles, so that the pivot axle moves upward in the key ways to the pivot aperture. Because the pivot axle is spring loaded, when the axle is aligned with the pivot aperture the collars 220 snap inwardly into the pivot aperture. In this position, the rocker arm is firmly secured in the pivot apertures and ready to use.

A pair of wheels 222 are connected with the front cross member 176. A rear panel 224 (see Fig. 7) ofthe exercise device 10 includes a pair of handles 226. The handles are elongate apertures, but other handle structures may be used. By lifting the rear ofthe device, the wheels engage the surface that the device is resting on. In this manner, the user may easily roll the exercise device to a different location. Alternatively, a wheel or wheels may be provided at the rear ofthe device and handles located at the front. Although two wheels are shown, one or more wheels, slide plates, rollers, or other devices may be used to ease movement ofthe device.

Figs. 26-29: Shock Mounting Position Variable Along Base Frame

As discussed above, a shock or shocks 108, 110 (i.e., dampening or resistance elements 76) may be provided as part ofthe dual deck treadmill exercise device to provide resistance to or dampening of movement ofthe treadles 12. Typically, one end of the shock 108, 110 is mounted to a treadle 12 while the other end ofthe shock 108, 110 is mounted to a portion ofthe frame 14 of the exercise machine (e.g., an upright 40, 42 ofthe frame as depicted in Fig. 1 or the side frame member 32, 34 ofthe frame 14 as depicted in Fig. 26). The shock 108, 110 can be a dampening shock, or can have a return spring incorporated into the shock 108, 110. Figs. 26-29 illusfrate an embodiment of the present invention wherein the location of such a shock 108, 110 relative to the frame 14 and the treadle 12 may be varied in order to adjust the no-load position ofthe freadles 12. Because the angle of action ofthe shocks 108, 110 acting on the freadles 12 is also affected, the damping or resisting force provided by the shock 108, 110 may also be varied by adjusting its position.

The no-load position of the freadles 12 is the position the treadles 12 will naturally gravitate towards if no load is applied to the freadles 12. The freadles 12 will pivot up and down around the no- load position. Adjustment ofthe pitch ofthe freadles 12 will vary the difficulty of a work out. All things being equal, the steeper the angle ofthe freadle 12, the more strenuous the workout.

Fig. 26 shows the base portion 300 of a dual deck treadmill device 10 having a pair of freadles 12 pivotally supported on a frame 14 as discussed elsewhere herein. In this embodiment, the freadles 12 have a common drive roller (which in this embodiment is a rear roller 30) and separate distal rollers (which in this embodiment are front rollers 28) to allow each freadle 12 to pivot upwardly and downwardly independent of the other; however, other arrangements discussed herein would also work with the variable location shock 108, 110 of Figs. 26-29. While only the base portion 300 is shown in Figs. 26 and 28 in order to emphasize the variable shock location, it should be understood that typically the base portion 300 would be incorporated into a frame 14 having uprights 40, 42 including handles 44, a control console 50, a motor control, and other particular features. As shown in Fig. 26, a first end 108A of a shock 108 is attached to the outside frame member 54 of a freadle 12. Other attachment locations on the freadle 12 may be possible. The other end 108B ofthe shock 108 is attached to a collar 302, which fits around a lead screw 304 incorporated into the base frame 14. The collar 300 traverses the length ofthe lead screw 304 as the lead screw 304 is rotated, thus changing the position ofthe lower end 108B ofthe shock 108. Because the shock 108 has generally a median length at no load, the angle at which the treadle 12 is supported with no load can be adjusted by moving the collar 302.

The movement of the collar 302 along the lead screw 304 is shown in Fig. 27, which shows that the collar 302 translates along the lead screw 300 as the threaded lead screw 304 is rotated. As also seen in Fig. 27, the end 108B ofthe sho^t 108 should be connected to the collar 302 such that the angle ofthe shock 108 relative to the collar 302 can vary as the collar 302 translates along the lead screw 304 or as the freadle 12 moves up and down. The mounting shown in Fig. 27 is a simple pivotal mounting. The lead screw 304 can be turned automatically by a motor controlled by the user, or can be turned manually. If it is turned by a motor, the motor can be controlled by inputs from the user or by program inputs by an on-board computer in order to adjust the incline ofthe freadles 12 during a user's workout. Preferably both treadles 12 are provided with variable pivot shocks 108, 110 mounted on lead screws 304. In such a case, the confrol ofthe location ofthe collars 302 on both lead screws 304 may be interconnected such that both are adjusted at the same time to insure both treadles 12 have the same relative median position.

Fig. 29 shows two examples of different positions ofthe adjustable shock attachment 306, one with the collar 302' proximate to the left end ofthe lead screw 304, holding the particular freadle 12' in a lower position. The other example is with the collar 302" to the right end of the lead screw 304 holding the particular freadle 12" in a higher position. The lead screw option provides a continuous adjustment structure that allows nearly infinite possibilities of positioning the bottom end 108B ofthe shock 108. As the screw 304 turns, the collar 302 translates along the screw 304. Once a desired location for the collar 302 is achieved, the rotation ofthe screw 304 is stopped, and collar 302 will remain stationary on the lead screw 304, thereby retaining the bottom 108B ofthe shock 108 in the desired location.

Other types of mechanisms can be used to adjust the position ofthe lower end 108B ofthe shock 108 along the frame 14 in order to adjust the angle of the unloaded treadle. For example, the lead screw 304 and collar 302 could be replaced by a discrete adjustment structure such as elongated rod 308 with apertures 310 and a pop pin structure 312, as shown in Fig. 28. The position ofthe bottom 108B ofthe shock 108 could be adjusted by sliding the collar 302 along the rod 308 until the desired position was reached, and then inserting the pop pin 312 into the desired aperture 310. A threaded member could be used in place of the pop pin 312. Alternatively, a set screw could be incorporated into the collar 302 to hold the collar 302 in place through friction. It should also be appreciated that a similar effect can be achieved by making the attachment location for the top 108A ofthe shock 108 variable on the side 54 ofthe treadle 12 via apertures 310 adapted to receive a pop pin on the top 108A ofthe shock 108, as seen in Fig. 29. Figs. 37-39: Shock Mounting Position Variable Along Frame Upright

Instead of mounting the shock 108, 110 (i.e., dampening or resistance elements 76) between the freadle 12 and the base portion 14 ofthe frame as shown in Figs. 26-29, and as described above, the shock 108, 110 may be mounted between the freadle 12 and an upright portion 40, 42 of the frame as shown in Fig. 37. Fig. 37 illustrates an arrangement that permits a user to adjust the position of a freadle 12 on a dual deck exercise device 10 (as described elsewhere herein) by adjusting the attachment point of a shock 108, 110 connected between the treadle 12 and a frame 14, 40, 42 ofthe exercise device 10. The lower end 108B ofthe shock 108 is attached to the side frame 54 ofthe freadle 12 and the upper end 108A ofthe shock 108 is attached on the upright member 40 ofthe frame. The upright member 40 of the frame is provided with a range of attachment points 314 at different heights on the upright member 40. This range of attachment points 314 provides different angular orientations for the freadle 12 for the desired exercise impact on the user.

Each treadle may be provided with its own shock 108, 110 so that the two treadles 12 can be adjusted to have different nominal slopes. In this manner the user can customize the workout to be more strenuous on one leg than the other.

The multiple shock attachment locations 314 can be discrete. For instance, as shown in Figs. 37 and 38, a pin 316 is used to attach the top end 108A, 110A ofthe shock to the upright 40, 42. The top end 108A, 110A ofthe shock 108, 110 is provided with a passage 318 for engaging the pin 316. The upright 40, 42 is provided with a series of apertures 314 that can be engaged by the pin 316 at the desired height. To adjust the attachment location of the shock 108, 110, the passage 318 at the end of the shock 108A, 110A is aligned with the desired aperture 314 in the side ofthe upright 40, 42, and the pin 316 is inserted into the aperture 314. The pin 316 maybe a threaded device 320, or may be spring-loaded to be held in place in the aperture 314. To readjust the position of the shock 108, 110, the pin 316 is withdrawn from the aperture 314, which leaves the top end 108A, 110A ofthe shock 108, 110 free to be realigned with a different aperture 314.

Alternatively, the attachment locations can be continuous as through the use of structure such as that shown in Fig. 39. The upper end 108A, 110A ofthe shock 108, 110 could be fashioned to move within a groove provided in the upright ofthe frame based on, for instance, the rotation of a lead screw 304. The positioning ofthe top end 108A, 110A ofthe shock 108, 110 could be virtually infinite between the ends ofthe lead screw 304. Rotation ofthe lead screw 304 to adjust the top end 108 A, 110A ofthe shock 108, 110 can be automatic, as by an electric motor, or manual with a crank. The treadles 12 can be adjusted to different heights or to the same heights depending on the user's desire. Fig. 39 shows a lead screw 304 embodiment for the adjustment ofthe top end 108A, 110A of the shock 108, 110. The top end 108A, 110A ofthe shock 108, 110 is attached to a collar 302, which collar 302 is threadedly engaged with the lead screw 304. When the lead screw 304 is rotated, the collar 302 moves upwardly or downwardly depending on the engaged threads and the rotation direction of the lead screw 304. This adjustment ofthe attachment position ofthe top 108 A, 110A of the shock 108, 110 can be vertical, angled, or curvilinear or in any other direction supported by the particular structure utilized. Fig. 30: Dual Treadle Exercise Device Having Two Motors

Heretofore arrangements have been discussed wherein a single driver roller and motor was used to drive both fread belts 18 on a dual deck exercise device 10. Fig. 30 illustrates an embodiment wherein each fread belt 18 is provided with its own driver roller 30 and motor 88. Fig. 30 shows the base portion 300 of a dual deck exercise device 10 having two adjacent treadles 12. Each freadle 12 has a pair of end rollers 28, 30 at opposite ends ofthe treadle 12. A continuous tread belt 18 is provided around the end rollers 28, 30. One ofthe two end rollers 28, 30 for each freadle 12 is the driver roller, though it should be appreciated that the driver roller could be located intermediately on the treadle 12 as well. In the embodiment shown in Fig. 30, the driver rollers 30 are the rear rollers 30. Additional rollers (i.e., intermediate rollers 916 as depicted in Fig. 84) or support structures 324 may be provided between the end rollers 28, 30 (e.g., Figs. 31-34 and accompanying discussion). It will be noted that each freadle 12 can be operably associated with a dampening device such as a shock 108, 110, a spring device for returning the freadle 12 to its upper position, and an interconnect (e.g., the rocker arm assembly 112 depicted in Fig. 10) to create a dependency between the motions ofthe freadles 12 (as one freadle is pushed down, the other freadle 12 is pushed up by the dependency device 112).

Fig. 30 is meant to emphasize that the driver roller 30 does not have to be common between the two adjacent freadles 12. In other words, more than one driver roller 30 can be utilized, such as one for each freadle 12. Each driver roller 30 is driven by its own motor 88 through a pulley 86, 98 and belt 96 system. A common controller (not shown) may be provided to assure that the motors 88 operate synchronously to make sure that the fread belts 18 are driven at the same speed. However, it is contemplated that each motor 88 can be separately controlled in order to have the fread belts 18 on the treadles 12 be driven at different speeds if desired by the user. While in Fig. 30 the drive rollers 30 are shown having axially aligned center lines, this is not a requirement for the instant invention, and each of the drive rollers 30 can have non-aligned axes of rotation. It should also be appreciated that while a belt 96 and pulley 86, 98 system is shown, any functionally equivalent arrangement such as cogs and gears, chain drives, direct drive, or friction drive would work as well. For information regarding alternative drives see Figs. 44A, 44B, and accompanying discussion. Figs. 31-34: Deck Suspension Systems Figs. 31-34 highlight a variety of types of deck 26 suspensions for use on the treadles 12 of the instant dual deck exercising apparatus 10. Fig. 31 shows a freadle 12 assembly that includes a pair of rollers 28, 30 at opposite ends of a frame 52. A continuous fread 18 is provided around the rollers 28, 30 such that it loops around the frame 52 and rollers 28, 30 to form an upper span 18A ofthe fread 18 and a lower span 18B ofthe fread 18. A top surface ofthe upper span 18A ofthe tread 18 provides the surface on which a user steps while using an exercise device 10 that incorporates the freadle 12 assembly. Preferably the continuous tread 18 is under tension such that it will frictionally engage the rollers 28, 30. The rollers 28, 30 may be provided with teeth to engage notches in the fread 18 for a more positive drive than relying on friction. Rotation of the rollers 28, 30 will thereby cause the fread 18 to move in a circuit around the rollers 28, 30. With continued reference to Fig. 31, ifthe rollers 28, 30 rotate in a clockwise direction, the upper span 18A will move generally to the right, while the lower span 18B will translate to the left.

An upper deck 26 and a lower deck 326 are positioned between the spans 18 A, 18B ofthe treadlδ. A suspension system 324 is provided between the upper and lower decks 26, 326 in order to properly position and cushion the upper deck 26. The embodiment shown in Fig. 31 uses the lower deck 326 as the primary frame structure 52 for supporting the rollers 28, 30. Alternatively, the lower deck 326 could be attached to a framework 52 that independently supports the rollers 28, 30. The upper deck 26 should have a generally flat and smooth top surface. The dimensions ofthe top surface ofthe upper deck 26 should correspond roughly with the length and width ofthe upper span 18A of the tread 18. The upper deck 26 can be a generally rectangular sheet of wood, such as ply wood or pressed board, or other like material positioned underneath the top span 18A ofthe fread 18. A friction reducing coating may be provided on the top surface ofthe upper deck 26 so that the upper span 18A of the fread 18 will slide easily across the top surface ofthe upper deck 26.

The suspension system 324 can be any arrangement that appropriately retains the upper deck 26 in position directly below the upper span 18A ofthe fread 18. The upper deck 26 may be positioned in supporting contact with the upper span 18A ofthe tread 18, or may be spaced slightly below the fread 18 under no load conditions. The suspension system 324 should also provide cushioning such that when a user steps on the upper span 18A ofthe tread 18, the momentum of the user's weight, as applied to the upper deck 26 through the tread 18, is dissipated somewhat smoothly rather than in a sharp jolt.

The suspension system 324 of Fig. 31 includes an array of resilient rubber bumpers 324 provided between the lower and upper decks 26, 326. Under no load conditions as shown in Fig. 31, the upper deck 26 rests on the bumpers 324 and is held in position immediately under the upper span 18A ofthe fread 18. In order to retain the upper deck 26 in place, the upper deck 26 may be adhered or otherwise attached to the bumpers 324. As a user impacts the upper tread 18A, the fread 18 deflects slightly downwardly against the top surface of the upper deck 26. Under load, the upper deck 26 deflects towards the lower deck 326. As the upper deck 26 is pressed towards the lower deck 326 by the weight and momentum ofthe user, the rubber bumpers 324 compress and deform to smoothly transfer the weight to the lower deck 326 and ultimately the frame 52. Other resilient materials that are well suited for absorbing shocks may be used rather than rubber to form the bumpers 324.

An alternative arrangement is shown in Fig. 32. A rigid bumper 328, such as hard plastic, wood, or metal, is positioned near the drive wheel (which is the rear roller 30 in Fig. 32) and is meant to restrict deflection ofthe upper deck 26 towards the lower deck 326 in the region ofthe rigid bumper 328. This prevents additional surface area ofthe fread 18 from contacting the drive roller 30, which can cause uneven driving ofthe tread 18 around the rollers 28, 30. This rigid bumper 328 is fixedly attached to both the upper and lower decks 26, 326. The opposite end ofthe upper deck 26 (the left end as viewed in Fig. 32) is free and is spaced apart from the lower deck 326 by a softer resilient bumper 324, such as a foamed rubber piece. Thus, the upper deck 26 is mounted in a generally cantilever fashion above the lower deck 326. The natural resiliency ofthe upper deck 26 acts as a flat spring that provides some cushioning effect in addition to the cushioning provided by the resilient bumper 326. The resilient bumper 324 can be positioned at any point between the rigid bumper 328 and the free end ofthe upper deck 26, and more than one bumper 324 can be used. The soft bumper 324 can be shorter than the distance between the two decks 26, 326, or can fit snugly between the two decks 26, 326 and contact the top and bottom deck 26, 326 before any deflection of the top deck 26 takes place.

Fig. 33 shows another embodiment ofthe suspension structure, and includes a plurality of relatively soft bumpers 324, such as those made by rubber or other similar materials, positioned between the upper and lower decks 26, 326. The multiple bumpers 324 can be positioned in arrays, randomly, or with one bumper 324 positioned near the centerline ofthe forward end ofthe upper deck 26.

Fig. 34 shows another embodiment ofthe suspension structure which incorporates relatively tall soft bumpers 324' and relatively short hard bumpers 324" in combination between the upper and lower decks 26, 326. This arrangement allows substantial upper deck 26 deflection initially when a load is applied to the upper deck 26 through the upper span ofthe fread 18 A; however it prevents excessive deflection once the weight is applied to the shorter hard bumpers 324". Initial downward deflection ofthe upper deck 26 occurs with the deck 26 in contact only with the tall soft bumpers 324". Once the deflection is sufficient that the upper deck 26 is brought in contact with the short hard bumpers 324", the short hard bumpers 324" prevent the upper deck from significant further deflection. Therefore, the initial shock ofthe user's weight and momentum is cushioned by the tall resilient bumpers 324', but excessive deflection is prevented by the short hard bumpers 324'.

Other types of resilient deck suspension structures for being positioned between the upper deck 26 and any deck below it can be utilized. Non-discrete structures, such as a single sheet of pliable material or other such resilient structure can be used between the upper and lower decks 26, 326 to dampen the impact force ofthe user's foot on the deck 26 during use. Fig. 35: Front Pivoting Treadle Assemblies

Heretofore, most ofthe discussion herein has described freadles 12 that pivot about an axis 16 that is at or near the rear portion of the treadles 12 (e.g., see Figs. 1, 26, 30 and 37). Fig. 35 shows a dual deck freadle device 10 similar to those described elsewhere herein, but wherein the freadles 12 pivot about a pivot axis 330 at or near a front portion 22 ofthe treadles 12. As seen in Fig. 35, a frame 14 is provided that includes an upright 40 at the front ofthe frame 14. Each freadle 12 is attached at its front end 22 to the upright portion 40 ofthe frame 14 in a pivotal relationship, with the rear end 24 ofthe treadle 12 suspended freely. Therefore, the front portion 22 ofthe freadle 12 is pivotally restrained, while the rear portion 24 ofthe freadle 12 will move in a generally vertical arc.

A motor 88 is mounted to the frame 14 in order to drive a moving fread 18 provided on the freadles 12. Connection ofthe motor 88 to the fread 18 can be by any ofthe means described in more detail throughout this description. For the purposes of illustration, a pulley 86 and drive belt 96 are shown in Fig. 35. The drive belt 96 attaches to a driver roller 28 at the front 22 of each freadle 12. There can be one motor 88 for a common front drive roller 28, or there could be two drive rollers 28, one for each freadle 12, each having its own drive motor 88. A housing or shroud may be provided at the front of the frame to cover the motor 88 and pivot 330. The left side cover has been removed in Fig. 35 so that the motor 88 and pivot 330 are visible.

With continued reference to Fig. 35, a shock absorber 108, 110 or other dampening or resistance device is provided between each treadle 12 and the frame 14. In the example shown, the treadles are suspended by shocks 108, 110 that connect to the upright 40, 42. Motion ofthe treadles 12 in the vertical plane is thereby resisted and dampened. The no-load position ofthe treadles 12 could be adjusted by varying the attachment point 34 of the shock 108, 110 to the upright 40, 42 or the freadle 12. While not shown in the figures, it should be understood that the shock absorber 108, 110 or other dampening device could connect to the lower portion 32 ofthe frame 14 rather than the upright 40, 42. An interconnecting device (not shown) might also be provided to make the motion of the freadles 12 complementary with each other.

When the user 332 faces forward and walks or runs forwardly, each treadle 12 pivots downwardly around its front pivot point 330 while the user's foot is in contact therewith during a forward to rearward motion ofthe foot. The foot is then picked up and brought back to the front end 22 ofthe treadle 12 during which time the freadle 12 moves from a downwardly angled position to an upwardly angled position, or at least a position having less of a downward angle, to be ready for the user 332 to reengage with the user's foot. The shocks 108, 110 can be spring-loaded for an automatic retraction to a higher position, or the shocks 108, 110 can be merely dampeners with external springs associated with the treadles 12 to bias the treadles 12 in an upward position. A single spring could be used or a double spring could be used or no spring could be used. This device could be utilized with the user 332 facing away from the upright post 40, 42 and running forward or backward, or with the person 332 facing towards the upright post 40, 42 as shown with the user 332 climbing forwardly or rearwardly.

Fig. 36: Dampening Device Associated with Dependency Structure

Fig. 36 shows an interconnecting device 334 for use in coordinating the movement ofthe treadles 12. This coordination is desirable so that a stepping action can be produced by the freadles 12 wherein the movement ofthe two freadles 12 is always 180 degrees out of phase. For example, when the left freadle 12 is at the top of its movement, the right freadle 12 will be at the bottom. Any downward motion in the left treadle 12 will result in a corresponding upward movement by the right treadle 12, and vice versa. One basic structure for interconnecting the freadles 12 in this fashion is a rocker-arm structure 112. Each treadle 12 is attached to a different side ofthe rocker arm 112 by a tie rod 134, 136. Any movement of one freadle 12 causes a reaction force in the opposite direction because the movement is fransmitted to the other freadle 12 through the rocker arm 112. This action is described in more detail below with specific reference to Fig. 36.

The interconnecting device 334 of Fig. 36 includes a rocker arm 112 pivotally associated with a pivot pin 120. The pivot pin 120 is supported by a bracket 336. The bracket 336 is preferably securely mounted to the base frame 114 below the treadles 12. A mounting pin 122, 124 for supporting a tie rod 134, 136 is provided at each end ofthe rocker arm 112 (preferably equidistance away from the pivot pin 130 but not required). A tie rod 134, 136 is pivotally attached to each mounting pin 122, 124 and extends generally upwardly to a bottom portion of a corresponding freadle 12 (not shown). The rocker arm 112 of Fig. 36 is formed with two facing plates 112A, 112B connected by a lower web 112C; however, other structures may be used to form the rocker arm 112, and the one illusfrated in Fig. 36 should be considered illusfrative only. The mounting pins 122, 124 for pivotally supporting the tie rods 134, 136 are positioned between the plates 112A, 112B ofthe rocker arm 112.

The rocker arm 112 interconnects the movement ofthe freadles 12 in the manner described herein. As one treadle 12 is pushed down and the corresponding tie rod 134 is pushed down, which pushes a first end ofthe rocker arm 112 down. The other end ofthe rocker arm is moved upwardly by the pivoting action ofthe rocker arm 112 about the pivot pin 120. This upward movement ofthe other end ofthe rocker arm 112 causes the other tie rod 136 to be pushed upwardly, and thus pushes the other treadle 12 upwardly. Ifthe tie rods 134, 136 are of equal length and are equally spaced apart from the pivot point 120 ofthe rocker arm 112, the corresponding movements ofthe freadles 12 will be equal with each other.

It should also be appreciated that any resistance applied to the movement of one treadle 12 will be fransmitted through the interconnecting device 334 as resistance to the opposite movement of the other treadle 12. If desired, resistance can be applied to the freadles 12 through the interconnecting device 334 rather than directly to the treadles 12. Fig. 36 illustrates the use of a rotational brake 338 for providing resistance to movement ofthe freadles by applying resistance to the interconnecting device 334. According to this embodiment, a pulley 340 is attached to the pivot pin 120. Optionally, the pulley 340 could be attached directly to the rocker arm 112. The pulley 340 is connected by a belt 342 to a rotational brake mechanism 338. The brake mechanism 338, by engaging with the pulley belt 342, provides resistance to turning ofthe pulley 340, and thereby provides resistance to the motion ofthe rocker arm 112, which in turn provides resistance to the motion of each ofthe treadles 12. The brake 338 can be adjusted from low load effect to a high load effect as desired by the user through normal motor confrols. The brake 338 shown in Fig. 36 could be a brake motor, a rotational brake, or an electro-magnetic brake.

Other types of brakes can be applied directly to the rocker arm or to a pulley system such as shown in Fig. 36. For example, a simple friction brake that resists rotation could be applied to the pin 120 ofthe rocker arm 112. Also, other types of resistance could be applied. For example a two- cylinder hydraulic dampening device 344, such as shown in Fig. 41A, and described in detail in the discussion of that figure, can be connected to the rocldng arms 112 to resist movement of the treadles 12. Figs. 40A-40B: Scissors Truss for Supporting Treadles

Fig. 40 A shows a base portion 300 ofthe dual deck fread exercise device 10 as described elsewhere herein utilizing a scissor-type truss support mechanism 346 to allow the treadles 12 to move downwardly and facilitate their upward motion under the force of a refracting spring 348. At the lower end ofthe scissor truss 346, one end 350 ofthe scissor truss is attached to the frame 14, while the other end 352 is slidably supported by the frame 14. Preferably the slidable end 352 ofthe truss 346 is provided with a wheel 354 that rides in a track 356 provided on the base 14. At the upper end ofthe particular scissor truss both ends 358 are attached to the treadle 12. Typically there are two scissor trusses 346 for each freadle 12, with one scissor truss attached to each side frame 52 ofthe freadle. This provides for stability and robustness of design, however, is not required as only one scissor truss 346 could be used if appropriately positioned directly below the freadle.

Fig. 40B shows the right hand freadle 12 in the lower position and the left hand treadle 12 in a higher position. The spring 348 shown with respect to the right hand scissor truss 346 pulls the bottom ends 350, 352 ofthe scissor truss together and biases the freadle 12 towards the upper position. Alternatively, a spring could be placed between the two front ends ofthe scissor truss or the two back ends ofthe scissor truss to urge those ends apart from each other. In use, the scissor frame 346 collapses and expands under the force of the user. An interconnect device 334 can be implemented to force one freadle up while the other freadle is being pushed down and vice versa. Dampeners 76, such as shown in Fig. 41, can be included in the structure to react with the scissor truss 346 or with the movement of the treadle 12 to create a dampening environment requiring more energy to actuate if desired. The motion ofthe treadles 12 shown in Fig. 40A is such that they remain parallel to the floor or any support surface upon which they are resting. Accordingly, a slope could be added to the treadles by tilting the portion ofthe frame 14 on which the scissor trusses 346 are supported. This could be accomplished for example by making the support track 356 on which the wheels 354 slide movable relative to the base 14 and providing a lift mechanism to raise one end ofthe track 356. Alternatively, an initial slope or tilt could be added to the treadles 12 by varying the lengths ofthe links 360 or moving the scissor point 362 ofthe scissor truss. Articulating motion ofthe treadles on the top ofthe scissor structure can be created by having additional structural links and springs and/or dampeners to allow the treadle 12 to move to a horizontal position either slightly or to a greater degree, depending on the complexity ofthe design.

Figs. 41A-41D: Two Chamber Hydrualic Dampening Device

Figs. 41A-D show a dual-cylinder shock 344 for operable attachment to the treadles 12 of a dual deck exercise device 10 as described herein, in order to provide resistance to movement ofthe freadles 12. The dual-cylinder shock 344 includes two cylinders 364. Each cylinder 364 has a reservoir portion 366 for containing a hydraulic fluid, such as oil. The reservoir portions 366 ofthe two cylinders 364 are connected via a connection line 368, which has a valve 370 positioned therein. A plunger 372 is positioned in each ofthe cylinders 364. Each freadle 12 is connected to a plunger 372 in order to altematingly push in and pull out the corresponding plunger 372. As the plungers 372 are pushed in and pulled out of their respective cylinders 364, they pump the hydraulic fluid back and forth between the reservoirs 366 through the connection line 368 and valve 370. The resistance to flow ofthe hydraulic fluid provided by the connection line 368 and valve 370 is fransmitted to the treadles to dampen their movement.

Fig. 41D provides an exploded view ofthe embodiment of Figs. 41A-D. It can be seen that the two cylinders 364 are formed side-by-side in a unitary body 374. A treadle end cap 376 and a reservoir end cap 378 are provided at opposite ends ofthe unitary body 374 to enclose the cylinders 364. The end caps can be connected to the unitary body by fasteners such as threaded bolts. Connection rods 380 are provided to connect the plungers 372 to the freadles or dependency structure. The plungers 372 are formed by pistons 382 and piston rods 384. The piston rods 384 are fixed to the pistons at one end, and are threadably engaged by the connection rods 380 at the other end. The threadable connections between each piston rod 384 and connection rod 380 is formed by a male portion 386 on the piston rod 384 and a female portion 388 ofthe connection rod 380. The pistons 382 slide within their cylinders 364 and are sealed to the interior ofthe cylinders by sealing rings 390. A push plate 392 may also be provided within each cylinder 364 at the junction between the connection rod 380 and the piston rod 384. The push plate 392 should be slidable within its cylinder, and fixed with respect to its corresponding piston 382. The push plate 392 may also be sealed with the cylinder 364 by sealing rings 390, although this is not required. A spacer 394 may be provided between each connection rod 380 and its corresponding push plate 392. A cylindrical structure 396 surrounds each piston rod 384 and helps to maintain the faces ofthe piston 382 and push plate 392 perpendicular to the side walls ofthe cylinder 364.

As seen in Fig. 41B, the reservoir end cap 378 is in sealed engagement with the cylinders 364. The space between the piston 382 and the end cap 378 forms the reservoir portion 366 of each cylinder. A passage 368 in the reservoir end cap 378 forms the connection line 368 between the two reservoir portions 366. The passage 368 may be extended to an opening 398 in the reservoir end cap 378 in order to allow filling ofthe reservoirs 366. A removable plug 400, preferably threaded, is provided in the opening 398 to keep the passage sealed. An adjustable needle valve 370 extends into this connection line 368. The needle valve 370 can be adjusted by turning it to vary the size ofthe aperture that permits flow of fluid between the reservoirs 366. The smaller the aperture, the more restricted the flow, and the higher the resistance.

In operation, as a treadle 12 is pushed downward by a user, the freadle pushes against its corresponding connection rod 380 either directly or through a dependency structure to urge the connection rod into the unitary body 374. As the connection rod 380 is pushed inward into the unitary body 374 by the freadle, the corresponding plunger 372 moves towards the end cap 378. In other words, the piston 382 moves towards the reservoir end cap 378.

Figs. 4 IB and 41 C serve to illusfrate the above described functioning ofthe dual-cylinder shock 344. Fig. 41B is a cross-section view showing the upper plunger 372 nearly fully extended outwardly and the lower plunger 372 nearly fully pushed inward. Fig. 41C shows the same dual- cylinder shock 344 after the freadles to which the plungers 372 are operably connected have been moved. In Fig. 41C, the upper plunger 372 has been pushed into its cylinder towards the reservoir end cap 378, and the lower plunger 372 has been withdrawn to expand its reservoir 366. In order to move from the position of Figs. 41B to 41C, it was necessary to force hydraulic fluid from the upper reservoir 378 into the lower reservoir 378 through the adjustable needle 370 valve and the connection line. The force required to pump the fluid from one reservoir 366 to the other provides resistance to movement ofthe freadles 12.

Each ofthe connection rods 380 have a pin receiving hole 381 for connecting with either the treadle or to a portion ofthe dependency structure. If an incompressible fluid is used as the hydraulic fluid, the dampening device can serve as the dependency structure. Fig.42: Spiraflex® Dampening Device

Fig. 42 shows the use of a Spiraflex® resistance mechanism 410 as a damper for the downward motion ofthe treadles 12. The Spiraflex® mechanism 410 is described in U.S. Patent Application No. 09/802,835, filed March 8, 2001, which is hereby incorporated by reference, and owned by the assignee ofthe present invention. A dependency structure between the treadles 12 interconnects the motion ofthe treadles such that upward motion of one freadle cause downward motion ofthe other freadle, and vice versa. The treadles 12 are tied to the Spiraflex® mechanism 410 by cables 412 and pulleys 414. As described in the aforementioned patent application, the Spiraflex® 410 is a resistance mechanism that provides nearly constant resistance.

The upward motion of either treadle 12 is resisted by the Spiraflex® mechanism 410. This resistance to upward movement is fransferred through the dependence structure to the other freadle 12, such that the Spiraflex® mechanism 410 effectively provides resistance to depression of either freadle 12. One ofthe treadles 12 is connected to rotational means within the Spiraflex® by a cable 412 routed through a pulley 414 while the other freadle 12 is connected to another rotational means within the Spiraflex® through another cable 412 and pulley 414 arrangement. As shown, the Spiraflex® 410 is mounted on the base frame 14, however it could be positioned in any functional location on the frame structure. Fig. 43: Combination Dampening and Biasing

Fig. 43 shows a dual deck fread climber 10 as described elsewhere herein, with shock-like dampeners 108, 110 used in conjunction with elastomeric spring return devices 416. The dampeners 108, 110 provide the primary resistance to movement ofthe treadles 12, while the elastomeric spring devices 416 act to return the freadles to a raised position. The shock-like dampeners 108, 110 are mounted to extend from one freadle to the frame upright 40, 42, in order to dampen the downward movement ofthe freadle 12 to provide resistance to the user. The dampener 108, 110 also resists the upward movement ofthe treadle, and based on the design ofthe dampener, can dampen the upward movement significantly or let it move relatively freely upwardly. This dampening ofthe upward movement can be desirable as it prevents the freadle 12 from snapping upwardly too quickly upon the user's weight being removed from the freadle during exercise.

The elastomeric spring 416 shown in Fig. 43 is attached between the treadle 12 and the frame upright 40, 42 to provide the return force to return the treadle to its high or upper position. If an interconnect is used between the treadles 12, such as a rocker arm 112, then the elastomeric springs 416 will cause the freadles to rise to a position where they are generally flush with one another, but not at the upper position. It should be noted that if an interconnect is used, the elastomeric spring 416 could be attached to the interconnect device rather than directly to the freadles 12. As shown, the left freadle 12 is pushed downwardly to stretch the spring 416. The elastomeric spring 416 in this example is a Soloflex® weight band, but it could also be some other type of elastomer or other similar type of material having elastic, resilient properties sufficient for the intended use. The position ofthe elastomeric spring 416 can be modified as long as the downward movement of freadle 12 loads the elastomeric spring in such a way as to create biasing force opposite the movement. For example, if the spring 416 is in the form of a material that when compressed has sufficient resilient properties to push the freadle 12 upwardly, the elastomeric spring could be positioned such that downward movement ofthe corresponding freadle compresses, rather than stretches, the spring. Figs. 44A and 44B: Drive Roller Exterior to Treadle Assembly Figs. 44A and 44B show an alternative embodiment for driving the continuous fread belt 18 on each freadle 12, either individually or in combination. Instead of directly driving one ofthe rollers 28, 30 in the treadle structure (such as shown elsewhere) to drive the fread 18, the instant embodiment utilizes a drive roller 418 that is external to the treadle structure to drive the fread 18. In the embodiment shown in Figs. 44A and 44B, the external drive roller 418 frictionally drives the fread 18 by impinging upon the fread and pinching it against one ofthe passive rollers 28, 30 in the freadle 12. The drive roller 418 is driven by a motor 88 and belt drive assembly 96. As the drive roller 418 is rotated by the motor 88, it creates a friction force against the fread 18 that causes the tread to translate between the rollers 30, 418.

The structure can include means for engaging and disengaging the drive roller 418 from the tread 18. This can be something that simply moves the drive roller up/down and into/out of contact with the fread. The drive roller 418 can drive the fread 18 in either ofthe two directions, depending upon which direction the drive roller is spinning. The speed ofthe fread 18 can be adjusted by adjusting the speed at which the motor 88 turns the drive roller 418. Preferably, the drive roller 418 and the tread 18 are in a no-slip relationship, in order to reduce wear on the fread. Ifthe pivot axis of the freadle 12 is the same as the pivot axis 82 for the freadle roller 30, the drive roller 418 will remain in tangential contact with the tread as the angle ofthe freadle is adjusted, without the need for any additional structure to maintain contact. Structure is contemplated to maintain contact between the drive roller 418 and the tread 18 where the pivot axis ofthe freadle is forward, rearward, above or below the pivot axis 82 ofthe treadle roller 30.

Alternatively, instead of contacting the continuous fread 18 directly, the drive roller 418 could be in direct friction contact relation with a roller 30 on the freadle 12 to tangentially drive the roller 30 and cause the fread 18 to move. In this arrangement, the drive roller 418 is put in pressure contact with the front or rear roller 28, 30 to create a frictional interface with the front or rear roller 28, 30. As the drive roller 418 is rotated by the motor 88, it in turn rotates the treadle roller 28, 30 it is in contact with. The roller 28, 30 being driven rotates and thus drives the fread 18. The drive roller 418 can drive the tread 18 in either ofthe two directions. The structure can include means for engaging and disengaging the drive roller 418 from the treadle roller 30. The drive roller 418 can be controlled by the user from the console to adjust the speed to the desired level.

The drive roller 418 can be positioned such that it contacts the fread 18 or roller 30 of both freadles 12 simultaneously so that both treads 18 are driven by a single motor 88. The treads 18 would move synchronously in this arrangement, which is generally advantageous. Alternatively, each freadle 12 could be provided with its own motor 88.

Again, ifthe pivot axis ofthe freadle is the same as the pivot axis 82 for treadle roller 30, the drive roller 418 will remain in tangential contact with the tread as the angle ofthe freadle is adjusted, without need for any additional structure to maintain contact. Structure is contemplated to maintain contact between the drive roller 418 and the fread 18 where the pivot axis ofthe freadle is forward, rearward, above or below the pivot axis 82 ofthe treadle roller.

Rather than relying on friction, the drive roller 418 could be in positive engagement with the freadle roller 30 through a cog belt or gear (not shown) coupled to the treadle roller 30. In this instance, the drive roller 418 could be provided with teeth that engage a gear coupled to the treadle roller 30. As the drive roller 418 rotates, its teeth would engage and drive the gear. The turning gear would rotate the freadle roller 30 to move the tread 18. Ifthe freadle rollers 30 shared a common gear, a single motor 88 could drive both treads 18. Similar controls as discussed above could be provided to move the teeth ofthe drive roller 418 in and out of contact with the gear, and to control the speed of the motor 88 to adjust the speed ofthe treads 18. Figs. 45 (A, B) - 47 (A, B): Dual Deck Exercise Machine Foldable into Storage Position

When not in use, it is desirable to be able to fold the exercise device 10 described herein into a more compact storage position. Figs. 45 A and 45B show a dual deck exercise device 10 in an extended Fig. 45 A and folded position Fig. 45B. As described elsewhere herein, the dual deck exercise device's basic components include a base frame 14, a pair of freadles 12 pivotally attached to the base frame, either directly or by some structural means, an upright 40 extending from the base frame 14, and side hand rails 44 extending laterally from the upright and generally along the length of the treadles.

The device 10 shown in Figs. 45A and 45B has a folding feature, where the freadles 12 fold up about their pivotal connection 420 to the base frame, and extend upwardly generally parallel to the upright 40 in a storage position. The folding nature ofthe device 10 allows it to take up less floor space when the device is stored or otherwise not in use. The device 10 is shown with freadles 12 extended, in an operating position, in Fig. 45 A, and with freadles 12 pivoted to the storage position in Fig. 45B. A releasable latch mechanism can be used to attach the freadles to the handrails or uprights in the storage position. Preferably the freadles 12 can pivot "over center" in order to stand upright more securely. In the device of Figs. 45A and 45B, the base frame 14 is provided at the front ofthe unit 10, and remains stationary to support the device 10 in the extended use position of Fig. 45 A and in the free standing storage position of Fig. 45B.

Various mechanisms are possible to retain the treadles 12 in the upright storage position of Fig. 45B. For example, a cable can be strung between the side rails to retain the freadles 12 in the upright position. A catch could be provided on the outside of each ofthe freadles 12 that selectively, or automatically engages a corresponding latch provided on each ofthe handles 44. Alternately, a releasable latch mechanism may be incorporated into the pivotal connection 420, holding the freadles 12 in place until a user releases the latch.

Figs. 46A-C display an alternate embodiment of a dual deck exercise device 10 in operational Fig. 46A, folded Fig. 46B, and storage Fig. 46C positions. In the device of Figs. 46A-C, the base frame 14 is provided under substantially the entire unit 10 when in the operational position of Fig. 46A. As with the embodiment shown in Figs. 45A and 45B, the present embodiment may be folded to create a smaller device footprint. The present embodiment's basic components here include a left and right freadle 12 assembly, a base frame 14, a housing 20, an upright 40, and a left and right side rail 44. Generally, the treadle 12 assemblies are pivotally attached to the base frame 14, either directly or by a structural means, within or next to the housing 20. The upright 40 is pivotally attached to the housing 20 by an upright pivot 420. The left and right side rails 44 are pivotally attached to the upright 40 by a side rail pivot 422.

As shown in Fig. 46A, when the embodiment is in an operating position, the bottom portion ofthe upright 40 extends beyond the upright pivot 420, and generally contacts the base frame 14. In alternate embodiments, the upright 40 may stop short ofthe base frame 14. Further, the left and right side rails 44, which serve as hand rails 40, extend generally perpendicularly from the upright 40 and parallel to the base frame 14 when the embodiment is in operating position.

The embodiment is shown in a folded position in Fig. 46B. hi this position the upright 40 has been pivoted around the upright pivot 420 so the upright 40 is generally prone and parallel to the base frame 14 and freadles 12. The upright pivot 420 should be located such that the base of the upright 40 will not extend beyond the front edge of the base frame 14 when the upright is rotated into the folded position shown in Fig. 46B. Most preferably, the upright pivot 420 is located so that the base ofthe upright 40 will be aligned with the front edge ofthe base frame 14 when the upright is rotated into the folded position of Fig. 46B.

The left and right side rails 44 may be rotated about the side rail pivot 422 so that they are also generally prone and parallel to the base frame 14 and freadles 12. Although the side rails 44 are shown rotated clockwise about the pivot 422 in Fig. 46B from their operating position of Fig. 46A, in alternate embodiments the side rails 44 may rotate counterclockwise. In yet other embodiments, the cloclcwise rotational angle of the side rails 44 about the side rail pivot 422 may terminate with the side rails 180 degrees beyond the position shown in Fig. 46B so that the side rails point generally towards the housing 20. A mechanism may be provided for locking the upright 40 and the side rails 44 in the folded position relative to the base frame 14.

Once the side rails 44 and upright 40 have been pivoted into the folded position of Fig. 46B, the embodiment may be stood on its front edge to reduce the overall footprint, as shown in Fig. 46C. The device 10 may simply be grasped and moved through a 90 degree angle to stand on its front edge. The unit is free standing on the front edge of the frame 14 and the bottom portion of the upright 40. ^• Alternately, a base frame pivot (not shown) may be affixed to the bottom front edge of the base frame 14, and the device 10 may pivot about the base frame pivot. Further, one or more lateral stabilization elements (not shown) may project outwardly from the base frame pivot at a 90 degree angle from the device's final storage position (i.e., the position shown in Fig. 46C to provide additional support against tipping ofthe device 10. The base ofthe upright 40 and front ofthe base frame 14 also act as lateral supports when the device 10 is raised into the final storage position shown in Fig. 46C. The exercise device 10 shown in Figs.47A and 47B differs from those shown in Figs. 45 and 46 in that the device of Figs. 47A and 47B has the freadles 12 mounted at the rear ofthe base frame 14, rather than the front. The exercise device 10 of Fig. 47A is shown in an unfolded operational position, whereas Fig. 47B illustrates the same device 10 folded into a storage position. The base frame 14 includes a rear base portion 14A on which the freadles 12 are mounted and a front base portion 14B on which the upright 40 is mounted. Side rails 44 are provided at the top ofthe upright 40. Optionally, the side rails 44 are selectively pivotal with respect to the upright 40 so they can be folded down generally parallel with the upright 40 if desired. The front and rear portions 14A, 14B of the base frame 14 are hinged together for pivotal movement with respect to each other. Preferably the hinge mechanism 424 is provided with a stop to prevent the two sections 14A, 14B from rotating past the operational position shown in Fig. 47 A. Also, preferably, the hinge mechanism 424 is provided with a locking mechanism to lock the front and rear base portions 14A, 14B into the operational position shown in Fig. 47A.

To adjust the exercise device 10 to the storage position shown in Fig. 47B, the locking mechanism would be released, and the rear base portion 14A pivoted upwards around the hinge 424 until it is generally upright and proximate to the upright 40. Preferably the rear base portion 14A can pivot to an over-center orientation so that it holds itself in the storage position. Any suitable latching mechanism may be used to retain the rear base portion 14A in the folded-up storage position of Fig. 47B. The front base portion 14B will support the entire unit 10 when adjusted to the storage position of Fig. 47B. As noted above, optionally the side rails 44 may be collapsed down so that they are generally parallel with the upright, to even further reduce the space occupied by the exercise device 10 in the storage position. The unit 10 could also be laid flat for storage on the rear base portion 14A ifthe side rails 44 are collapsed. Rollers (not shown) may be provided on the front edge ofthe front base 14B portion to aid in moving the device 10 when in the storage position. Figs. 48A and 48B: Protective Shroud

Figs. 48A and 48B display an embodiment of an exercise device 10 incorporating a protective housing 20. Generally, the housing 20 is of single-piece construction, and extends about the front, left side, and right side ofthe exercise device main frame 14. Fig. 48A displays an isomefric view ofthe housing 20 generally from behind and to the right ofthe housing, while Fig. 48B shows an isometric view from generally in front ofthe housing 20. The housing 20 protects the inner workings ofthe exercise device 10 to make it less likely that a hand or foot could be pinched by the reciprocating freadles 12 or caught in the moving tread belt 18 ofthe treads. The housing 20 also helps keep out dust and other debris that could foul the workings ofthe exercise device 10.

Typically, the housing 20 extends sufficiently vertically to encompass the treadles 12 at all times, including while the freadles 12 are in motion. Accordingly, the upper side wall 20' ofthe housing 20 is sloped from back to front at an angle approximating the freadle throw. Generally, the height ofthe shroud 20 is equal to the deck height ofthe freadles 12 at maximum freadle extension. The housing 20 may incorporate a spring, shock, or other resistive element to act against the vertical motion ofthe front ofthe freadle 12. In such cases, the resistive element is generally affixed to a portion ofthe freadle 12 at one end and to the housing 20 at the other end. Alternately, the housing 20 may include an interconnection device (as described elsewhere herein) to transfer motive force between the treadles 12. Preferably the shroud 20 is a hard durable material such as a molded plastic. The shroud 20 may be attached to the frame 14 by bolting or similar removable fasteners to permit removal ofthe shroud 20 for repair or maintenance ofthe device 10. Fig.49: Dampening and Biasing of Front Drive Exercise Machine, and Combination Stepper and Treadmill

In the front drive exercise machine 10 of Fig. 49, an upright frame member 40 extends upwardly from the base frame 14. The frame members 40 are of any desired shape possessing sufficient rigidity and sfrength so as not to deform or fail in use. The frame members 40 are joined by any suitable technique such as welding or bolting. If desired, the upright 40 is removably coupled to the base frame 14 for convenience of shipping and storage. A console and handlebar 44 assembly (also referred to herein as side rails) is removably coupled to the upright 40, for convenience of shipping and storage. With a few exceptions, the same arrangements of components as used in the rear drive embodiment described elsewhere in this document are generally suitable for the front drive embodiment of Fig. 49. For additional description related to front drive embodiments see Fig. 35 and related discussion.

Two freadle assemblies 12, a right assembly and a left assembly, are pivotally coupled to the upright 40 on the respective sides thereof and along a common axis 330, although a common axis is not required. If desired, two uprights (not shown) may be used instead of a single upright, and the right and left treadle assemblies may be pivotally coupled between the two uprights (not shown). The treadle assemblies 12 pivot about an axis 330. Illustratively, the pivot axis 330 is the axis of a drive shaft 82 that drives both the front roller 28 ofthe left treadle assembly 12 and the front roller 28 ofthe right freadle assembly 12. A single driven roller 28 may be used instead of separate driven rollers 28. The pivot axis 330 may be offset from the drive shaft 82 if desired, with other structures supporting the pivoting action. The pivot 330 may be fixed as shown, or may be variable. Different mechanisms may be used for establishing variable pivot points, including mounting the right and left treadle assemblies 12 and the drive shaft 82 in a sub-frame, and providing a variable position locking mechanism between the sub-frame and the upright 40 or uprights 40, 42. (See for example Figs. 26- 29 and 37-39 and related discussion.) An illustrative variable position locking mechanism is an array of holes 314 in the upright (as illustrated in Fig. 37) and a spring-loaded peg mechanism in the sub- frame. Others include collar and lead screw, notches, clamps and ledges.

Each ofthe treadle assemblies 12 is a separate treadmill with its own belt 18, deck 26, and front and rear rollers 28, 30. Although each ofthe freadle assemblies may be driven by its own motor 88 if desired, advantageously both freadle assemblies 12 are driven by a common drive shaft 82 and the same motor 88. This assures that each belt 18 travels at the same speed. The freadle assemblies 12 also are interconnected to provide a balanced relationship between the right and left sides during a workout and to provide some additional cushioning. The balanced relationship may be achieved in a variety of ways, including by a rocker assembly 112 or a belt assembly. If desired, the left and right assemblies 12 may be locked together at an incline to get a traditional treadmill workout.

Pivotal movement ofthe freadle assemblies 12 about the pivot point 82 is controlled by the user's stepping action (stride, gait, weight, and so forth) together with a dampening effect and a biasing effect imposed by the combination dampening and biasing devices 76 (such as shocks 108, 110 as discussed in other areas of this specification). A dampening force is one that resists movement ofthe freadles 12 in at least one direction. Typically the desired dampening device 76 resists downward motion of its associated freadle 12. A biasing force tends to urge the freadle 12 towards a neutral position. Ifthe freadle 12 is displaced from the neutral position, the biasing device 76 urges it back towards the neutral position. Typically, the biasing devices 76 will urge the treadles 12 back towards an upper position, after the freadles 12 have been depressed to a lower position.

A suitable device 76 for providing both dampening and biasing is disclosed in United States Patent No. 5,622,527, issued April 22, 1997 and incoφorated herein in its entirety by reference thereto. If desired, separate devices may be used for dampening and biasing. The ends ofthe dampening and biasing devices 76 pivot either at fixed positions 314 on the upright 40 and freadle assembly 12, or at variable positions on one or both ofthe upright and treadle assembly, as illustrated in Figs. 26-29 and 37-39). The ability to vary the pivot positions 314 allows the biasing force to be adjusted, and allows the bias angle (deck inclination) ofthe deck 26 to be adjusted with respect to the horizontal. The degree ofthe dampening resistance and the biasing force may be fixed or adjustable as desired. In the combination dampening and biasing device 76 shown in Fig. 49, illustratively both the degree of dampening resistance and the biasing force are respectively adjustable by dials 426A, 426B located on an upper cylinder 428A and/or on a lower cylinder 428B. The dampening effect may be achieved using any suitable resistance devices such as hydraulic cylinders, flywheels, brakes, and so forth. The biasing effect may be achieved using any suitable devices such as coil springs, torsion springs, elongate elastomeric members, and so forth.

To operate the exercise machine 10 of Fig. 49 in a normal mode, the user 332 adjusts the dampening effect and the biasing effect as desired, steps upon right and left side foot support platforms (not show), adjusts the workout profile on the console as desired (the respective belts 18 of the right and left freadle assemblies 12 begin to move), and steps from the right and left foot support platforms onto the right and left belts 18, respectively. The exercise machine 10 may also be operated in a treadmill mode by locking the left and right treadle assemblies 12 together, or may be operated in a stepper mode by maintaining the belts 18 stationary (motor off).

In normal mode operation as shown in Fig. 49, the user 332 has just stepped on the moving belt 18 ofthe right treadle assembly 12 and has shifted his weight from the left foot (which has been carried to the rear ofthe treadle assembly 12 by the moving belt 18) to the right foot. The downward force exerted by the right foot on the freadle 12 tends to rotate the right freadle 12 downward around the pivot 330. This motion ofthe freadle 12 is opposed by a biasing force and a dampening force. The dampening force is variable depending on the speed at which the treadle 12 is rotating. The faster the treadle 12 rotates, the more resistance the dampening device 76 will provide. The biasing force is dependent on how far the treadle 12 has been displaced from its neutral position. The left freadle assembly 12 begins to rise because the left foot has been unweighted and because the downward force on the right treadle 12, due to the weighted right foot, is fransferred by the rocker assembly as an upward force into the left treadle 12. Next, the left foot becomes fully unweighted as it is raised and moved from the rear ofthe deck 26 ofthe left freadle assembly 12 toward the front ofthe deck 26 of the left freadle assembly 12. Meanwhile, the fully weighted right foot is carried toward the rear ofthe deck 26 ofthe right treadle assembly 12 with the moving belt 18, and the inclination of he right treadle assembly 12 increases due to the weight while the inclination ofthe left freadle assembly 12 decreases due to the biasing force and the fransferred force. At a slow belt speed (slow pace), the freadle assemblies 12 travel through a greater arc range than at high belt speeds (fast pace), all else being equal.

If desired, the belts 18 ofthe freadle assemblies 12 may be run in reverse, permitting the user to step away from the upright 40 or uprights 40, 42, either by stepping backward or by turning around and stepping forward.

As the user slows his pace at the end ofthe workout, the left and right treadle assemblies 12 may bottom out by striking against the base frame 14. Bottoming out may also occur ifthe biasing force is not properly set. The exercise machine 10 should include a mechanism such as a bumper structure or bottom out assembly 154 (not shown in Fig. 49, but see Fig. 60, and accompanying discussion) to absorb some ofthe force ofthe impact in order to both cushion the user and avoid damage to the exercise machine. Figs. 50-51: Rocker Arm Assembly Having Universal Joint and/or Biasing Effect

As shown in Fig. 50, for a front drive exercise machine 10, two freadle assemblies 12, a right assembly and a left assembly, are pivotally coupled between two uprights 40, 42. Alternatively, a single upright 40 may be used and the treadle assemblies 12 may be pivotally coupled to the single upright 40 on the respective sides thereof and along a common axis. Also, as discussed elsewhere herein, the treadle assemblies 12 may be pivotally connected to the frame at a rear portion ofthe frame 14. Each ofthe treadle assemblies 12 is a separate treadmill with its own belt 18, deck 26, and front and rear rollers 28, 30. The treadle assemblies pivot about a pivot point 330, which illusfratively is a drive shaft 82 that drives both the front roller 28 ofthe left freadle assembly 12 and the front roller 28 ofthe right treadle assembly 12. The pivot point 330 may be fixed as shown, or may be variable. Although each ofthe treadle assemblies 12 may be driven by its own motor 88 if desired, advantageously both freadle assemblies 12 are driven by a common drive shaft 82 and the same motor 88. This assures that each belt 18 travels at the same speed.

The freadle assemblies 12 are interconnected such that as one treadle assembly 12 is pushed down, the other freadle assembly 12 is correspondingly pushed up. This interconnection provides a balanced relationship between the right and left sides during a workout and provides some additional cushioning. The interconnection mechanism 334 in the embodiment shown in Fig. 50 is a rocker assembly. A central portion of a rocker arm 112 is pivotally coupled to the front ofthe base frame 14 by a pivot rod 120. The ends ofthe rocker arm 112 are coupled to respective tie rods 134, 136 using respective universal joints 138. The left tie rod 134 is coupled to a pivot 128 on a side frame 54 ofthe left freadle assembly. Similarly, the right tie rod is coupled to a pivot on a side frame ofthe right freadle assembly 12. Ball joints 138 should be used at the ends ofthe rocker arm 112 and where the tie rods 134, 136 are coupled to their respective freadle assemblies 12 because the pivots 128, 130 on the side frame members 54, 56 ofthe freadle assemblies 12 move in an arcuate path along one plane while the rocker arm ends move in an arcuate path along a peφendicular plane, which imposes a complex relative motion at the ends ofthe tie rods 134, 136.

In one embodiment, as illusfrated in Fig. 51, the rocker arm 112 is fabricated with two opposing sheet metal arm forms 112A, 112B, interconnected by an integrated metal section 112C bent at right angles from each ofthe arm forms. The ball joints 138 are located between the arm forms 112 A, 112B at each end ofthe rocker arm 112.

The term "tie rod" 134, 136 is inclusive of fixed length rods as well as variable length rods such as turnbuckles. A variable length tie rod 134, 136 can be used to adjust the angle of its associated freadle assembly 12. As the variable length rod 134, 136 is made longer, it will increase the pitch ofthe treadle assembly 12.

The rocker arm assembly 112, depicted in Fig. 50, functions as follows. Pivotal movement of the freadle assemblies 12 about the pivot point 120 is controlled by the user's stepping action (stride, gait, weight, and so forth) together with a dampening effect and a biasing effect imposed on each of the freadle assemblies 12. As the user steps down on, say, the belt 18 ofthe left freadle assembly 12, the left freadle assembly 12 pivots in a downward direction about the left driven roller 28 and drives the left tie rod 134 downward. This causes the left end ofthe rocker arm 112 to be pushed down, which causes the right end ofthe rocker arm 112 to raise. The upward movement ofthe rocker arm 112 is transmitted through the right tie rod 136 to urge the right freadle assembly 12 to pivot in an upward direction about the right driven roller 28.

The rocker arm assembly 112 may be provided with biasing devices, if desired. Fig. 51 shows right and left springs 428 as the biasing devices. The springs 428 are coupled between the respective ends ofthe rocker arm 112 and respective mounts on the base frame 14. When the freadle assemblies 12 are at the same inclination ("neutral inclination"), the springs 428 are under the same degree of compression or extension. As the user steps down on, say, the belt 18 ofthe left freadle assembly 12, the left freadle assembly pivots in a downward direction about the left driven roller 28. The left end ofthe rocker arm 112 is pushed down, causing the right end ofthe rocker arm 112 to push up and urge the right freadle assembly 12 to pivot in an upward direction about the right driven roller 28. At the same time, the left spring 428 is placed in greater compression (or extension depending on the arrangement ofthe spring with respect to the rocker) and the right spring 428 is placed in tension (or at least in less compression than the left spring), creating a net biasing force that opposes the downward force exerted by the user's weighted foot on the belt 18 ofthe left freadle assembly 12. When the user transfers his weight from the left foot to the right foot, the biasing devices 428 work in concert with the user's weighted right foot to cause the right treadle assembly 12 to pivot in a downward direction. However, as the neufral inclination position is passed through, the biasing devices 428 begin to oppose downward force exerted by the user's weighted right foot, as described above for the weighted left foot.

The biasing devices 428 shown in Fig. 51 may be used with rocker arms 112 that do not employ ball joints 138. Moreover, the precise location on the rocker arm 112 to which the ends ofthe biasing devices 428 are attached and the manner of attachment are not critical. Moreover, the other ends ofthe biasing devices 428 may be coupled directly to the frame 14, or to other structures that are independent of movement ofthe rocker arm 112. These other structures preferably are in the general plane of movement ofthe rocker arm 112, but otherwise may reside below the rocker arm 112 (for example, the position shown in Fig. 51) or above the rocker arm 112 (for example, 180 degrees displaced from the position shown in Fig. 51). Figs. 52A-52B: Under-Treadle Biasing Device

As noted above, in a dual-movable belt freadle assembly exercise machine 10, pivotal movement ofthe freadle assemblies 12 about their pivot axes 330 is controlled by the user's stepping action (stride, gait, weight, and so forth) together with a dampening effect and/or a biasing effect imposed upon the freadle assemblies 12. The dampening and the biasing effects may be imposed upon each freadle assembly 12 by one device or by separate devices.

Fig. 52A shows an example ofthe use of biasing devices 428 under each ofthe freadle assemblies 12. The biasing devices 428 urge the treadle assemblies 12 upward to a no-load, or neutral position. The biasing devices 428 shown in Fig. 52A illusfratively are springs 428 that are coupled between the bottom 430 of each ofthe freadle assemblies 12 and the base frame 14. Preferably the compression and tension properties ofthe springs 428 are generally equal and the attachment points 430 on the treadle assemblies 12 are mirrored so that the freadle assemblies 12 are biased at the same inclination and exert generally equal biasing forces to the user's left and right feet for the same weightings. When the freadle assemblies 12 are at the no-load, or neufral inclination, the springs 428 are under the same degree of compression due to the weight ofthe freadle assemblies 12. As the user steps down on, say, the belt 18 ofthe left freadle assembly so that his foot frictionally engages the belt 18, the left freadle assembly 12 pivots in a downward direction about its pivot axis 330 and compresses the left spring 428 (see Fig. 52B). The compression ofthe left spring 428 creates a biasing force that pushes up to oppose the downward force exerted by the user's weighted foot on the belt 18 of the left treadle assembly 12. As the user's foot is unweighted, which occurs as the user steps on the belt 18 ofthe right treadle assembly 12, the biasing force tends to restore the left freadle assembly 12 to its neufral inclination position. Dampening devices (not shown) preferably, but not necessarily, are used along with the springs 428. The dampening devices preferably resist downward movement ofthe freadle assemblies 12. The dampening devices may also resist the upward movement ofthe freadle assemblies 12 caused by the springs 428 to prevent the treadles 12 from snapping back too quickly.

The top ends ofthe springs 428 are coupled to the treadles 12 so as to exert a push-up biasing force on the treadle assemblies 12. The mechanism shown in Fig. 52A includes a flange 430 that extends in a sideward direction from a lower portion ofthe frame 52 ofthe freadle assembly 12. The flange 430 should be lower than the level ofthe belt surface 18 engaged by the user's foot to avoid contact ofthe spring 428 by a user's foot. Other suitable attachment mechanisms include the right and left side foot support platforms (not shown) as well as areas ofthe housing (not shown), provided they possess sufficient rigidity and sfrength so as not to deform or fail in use.

Where a housing is used that extends along the bottom of a freadle assembly 12, the spring 428 attachment point 430 may be along the longitudinal centerline ofthe treadle assembly 12, rather than offset therefrom. If desired, a flange 430 extending from the frame 52 of a treadle assembly 12 may be bent under the freadle assembly 12, which would also permit the attachment point 430 to be along the longitudinal centerline ofthe treadle assembly 12 rather than offset therefrom.

The bottom ends ofthe springs 428 may be attached directly to the base frame 14, or to any other structure that is stable relative to the movement of the freadle assemblies 12.

If the ability to adjust the inclination ofthe freadles is desired, a variable height mechanism (not shown) may be used with the springs, illustratively at the attachment points 430. A variety of variable height mechanisms are well known, including, for example, screw-type mechanisms and pin- in-hole mechanisms. The variable height mechanisms permits the inclination to be identical or different between the freadle assemblies 12, as desired by the user.

An example of a suitable variable height mechanism for the lower ends ofthe springs 428 is a movable platform that rises from the base frame 14 and may be positioned at a variable distance therefrom. The lower ends 428 ofthe springs are attached to this platform, and the user varies the distance ofthe platform from the base frame 14 to adjust the inclination ofthe freadle assemblies 12. The height ofthe platform may be manually adjusted or adjusted by motor under user confrol from the user console.

Ifthe ability to adjust the user-perceived biasing force is desired, the distance between the spring and the pivot point of the freadles may be made adjustable as disclosed elsewhere in this specification. The neufral angle of inclination ofthe freadle assemblies 12 can also be adjusted by varying the attachment location ofthe biasing device 428 relative to the pivot point 330. The closer the biasing device 428 is moved to the pivot point 330, the steeper the incline. In order to accomplish this there would need to be multiple attachment locations for the biasing device on the base frame 14 and on the freadle assembly 12. It should be noted that a change in the location relative to the pivot point 330 will also vary the biasing force because of a change in leverage. The closer the biasing device is placed to the pivot point 330, the less resistance to pivoting ofthe treadle assembly 12. Figs. 54-59: Biasing Mechanisms for Exercise Machine

Figs. 54-59 show various additional embodiments of biasing mechanisms 428 that can be provided directly underneath the treadle assemblies 12. Fig. 54 shows one type of biasing mechanism. The freadle assemblies may be linked by a reciprocating linkage (not shown in Figs. 54- 59), such as any ofthe various rocker arm assemblies shown and described elsewhere in this document. An elongated flat spring 428, preferably metallic, is supported above the base frame 14 by a spring support bracket 430, and extends in both directions toward the right and left sides ofthe exercise machine, underneath the left and right freadle assemblies 12. Respective protrusions 432 project downward from the left and right freadle assemblies 12, illusfratively generally from the longitudinal centerline thereof although they may be located anywhere provided that the arms ofthe flat spring 428 are sufficiently long to engage the protrusions 432. If an interconnecting device is not used, the arms ofthe flat spring 428 are in engagement with the protrusions 432 during all or substantially all ofthe stroke ofthe left and right treadle assemblies 12. If an interconnecting device is used, the protrusions 432 will typically engage the arms ofthe flat spring 428 at the neutral inclination and below, but will be disengaged as the freadle assemblies 12 move upwards above the neufral position. Where the left and right freadle assemblies 12 are provided with a sturdy and rigid housing 20, the protrusions 432 may project from the lower housing panel 20 (hidden in the figure). Where the housings 20 are not sufficiently sturdy and rigid or where they are not used, the protrusion 432 for each ofthe freadle assemblies 12 may be a part of and project from a bracket (not shown, but see the bracket 156 in Fig. 60 for an example) that extends beyond the width ofthe belt 18 ofthe freadle assembly 12 and that has one upward-extending flange or two upward-extending flanges that couple to the internal frame (not shown) ofthe freadle assembly 12.

The protrusions 432 may be made of any material, although the material should be such that it readily slides across the flat spring 428 as the flat spring 428 deforms upon engagement by the protrusions 432. Suitable materials include hard plastics and composites, as well as metals coated with a low friction material.

The biasing mechanism 428 of Fig. 54 functions as follows in the operation ofthe left freadle assembly 12. The function ofthe biasing mechanism 428 is identical for the right freadle assembly 12. As the user steps on the belt 18 ofthe left freadle assembly 12 and weights his foot, the left treadle assembly 12 moves downward about its pivot axis. The arm ofthe metal flat spring 428 is engaged by the protrusion 432 ofthe left freadle assembly 12 and the flat spring 428 resiliently deforms, thereby imposing a progressively increasing biasing force in opposition to the arcuate downward motion ofthe left treadle assembly 12. As the user completes his step and begins to unweight his foot, the biasing force causes the left treadle assembly 12 to return to its neutral inclination.

Preferably the flat spring 428 is located near the free ends ofthe treadle assemblies 12 to exert maximum leverage on the freadle assembly 12. In this fashion the restitution force ofthe flat spring 428 can be minimized for a desired biasing force. Alternatively, the biasing effect and inclination of the freadle assemblies 12 could be varied by providing the flat spring 428 on a movable support bracket that can be adjusted forwardly and rearwardly on the base frame 14. As the support bracket is moved rearwardly, it will exert a smaller biasing force on the freadle assemblies 12 due to the shorter lever arm that results from being moved closer to the pivot point. The inclination ofthe freadle assemblies 12 would be increased as the flat spring 428 moves closer to the pivot point.

Fig. 55 shows a biasing mechanism 428 used with right and left freadle assemblies 12 that have respective right and left dampening devices 76, illusfratively ofthe hydraulic cylinder type. The biasing mechanism 428 shown in Fig. 55 is identical to the biasing mechanism 428 shown in Fig. 54. The right dampening device 76 has one end pivotally mounted to the outside side ofthe right freadle assembly 12, and another end mounted to a right upright frame member (not shown). The left dampening device has one end pivotally mounted to the outside side 54 ofthe left freadle assembly 12, and another end mounted to a left upright frame member (not shown). The dampening devices 76 will provide resistance to downward movement of their respective freadle assemblies 12. The resistance provided by the dampening devices 76 may be dependent on the speed at which the freadle assemblies 12 are moving. The damping devices 76 may also provide some resistance to upward movement ofthe freadle assemblies 12 in order to show the rate at which the unweighted freadle assemblies are pushed upwards by the flat springs 428.

Figure 56 shows a biasing mechanism 428 uses a leaf spring 428 is supported in a concave aspect relative to the freadle assemblies 12 by a short spring support bracket 430he arms ofthe leaf spring 428 and in both directions toward the right and left sides ofthe exercise machine and into engagement with the underside ofthe left and right treadle assemblies 12. If a reciprocating linkage is not used, the arms ofthe leaf spring 428 are in engagement with the freadle assemblies 12 throughout all or substantially all ofthe stroke thereof. If a reciprocating linkage is used, the freadle assemblies 12 may disengage from the leaf spring 428 during the upper portion of their range of motion. The upturned ends ofthe leaf spring 428 engage the housing bottom panels 20 ofthe freadle assemblies 12 illusfratively about the longitudinal centerline thereof, although they may be made shorter or longer to engage the housing bottom panels 20 in an area other that about the longitudinal centerlines thereof, if desired. Where the freadle assemblies 12 are provided with a sturdy and rigid housing 20, the leaf spring ends may engage the housing panels 20 directly. However, where the housings 20 are not quite sufficiently sturdy and rigid, strike plates may be used in the area engaged by the leaf spring ends. Where a housing is not used or is very weak, a bracket (not shown) that extends beyond the width of the belt 18 ofthe freadle assembly 12 and that has one upward-extending flange or two upward- extending flanges that couple to the internal frame (not shown) ofthe treadle assembly 12 may be used to provide a sfrike plate. The strike plate may be made of any material, although the material should be such that the end ofthe leaf spring 428 readily slides across it as the leaf spring 428 deforms upon engagement by the sfrike plate. Suitable materials include hard plastics and composites, as well as metals coated with a low friction material. The use ofthe concave leaf spring 428 of Fig. 56, as opposed to the flat spring 428 of Fig. 54, is advantageous because it permits the spring 428 to contact the freadle assembly 12 over a relatively longer range of motion.

The biasing mechanism 428 of Fig. 56 functions as follows in the operation ofthe left freadle assembly 12. The function ofthe biasing mechanism 428 is identical for the right freadle assembly 12. As the user steps on the belt ofthe left freadle assembly 12 and weights his foot, the left treadle assembly 12 moves downward about its pivot axis. Depending on the embodiment, the arm ofthe leaf spring 428 is engaged by the bottom of a housing 20, a strike plate, or a protrusion 432 and the leaf spring 428 resiliently deforms, thereby imposing a progressively increasing biasing force in opposition to the arcuate downward motion ofthe left freadle assembly 12. As the user completes his step and begins to unweight his foot, the biasing force causes the left freadle assembly 12 to return to its neufral inclination.

Fig. 57 shows a biasing mechanism 428 that uses a relatively short leaf spring 428 that is supported in a convex aspect relative to the freadle assemblies 12 by a long spring support bracket 430. The leaf spring 428 extends a relatively short distance in both directions toward the right and left sides ofthe exercise machine 10, underneath the freadle assemblies 12. If a reciprocating linkage is not used, the arms ofthe leaf spring 428 are in engagement with the treadle assemblies 12 throughout all or substantially all ofthe sfroke thereof. The protrusions 432 on the bottom ofthe treadle assemblies 12 engage the leaf spring engage 428 at the inside edges thereof, near where the leaf spring 428 is supported by the spring support bracket 430. Where the freadle assemblies 12 are provided with a sturdy and rigid housing 20, the leaf spring 428 may engage the housing panels 20 directly. However, where the housings 20 are not quite sufficiently sturdy and rigid, a sfrike plate may be used in the area engaged by the leaf spring 428. Where a housing 20 is not used or is very weak, a bracket (not shown) that is coupled to the internal frame (not shown) ofthe freadle assembly 12 and extends downward just beyond the bottom ofthe housing 20 or roller may be used to provide a strike plate. The sfrike plate may be made of any material, although the material should be such that the end ofthe leaf spring readily slides across it as the leaf spring 428 deforms upon engagement by the strike plate. Suitable materials include hard plastics and composites, as well as metals coated with a low friction material. Fig. 58 shows a biasing mechanism 428 that uses a multiple section torsion spring 428 that is supported on the base frame 14. The freadle assemblies 12 are shown in an exaggerated lifted position so that the multiple section torsion spring 428 is more clearly visible. The base section 434 ofthe torsion spring 428 is mounted to the base frame 14 by a number of mounting clips 436. The free ends 438 ofthe torsion spring 428 extend inward from coils 440. The free ends 438 engage the housing bottom panels ofthe freadle assemblies 12 along the bottoms thereof, and the torsion spring 428 resiliently deforms to provide the biasing effect. If a reciprocating linkage is not used, the free ends 438 are in engagement with the freadle assemblies 12 throughout all or substantially all ofthe stroke thereof. As in the other embodiments ofthe biasing mechanism 428, the inward-extending free ends 438 ofthe torsion spring 428 may engage the housing 20 directly if it is sturdy and rigid enough, or may engage any suitable strike plate. i a variation ofthe Fig. 58 embodiment, the coils ofthe torsion spring 428 may be located near the centerline ofthe base frame and the free ends 438 ofthe torsion spring 428 may extend outwardly rather than inwardly. To adequately support such a torsion spring 428, a center frame member (not shown) may be provided, and the multiple section torsion spring may be secured by clips 436 along the center frame member.

Fig. 59 shows a biasing mechanism 428 that uses a dual pronged flat metallic spring 428 that is supported on cross members 36 ofthe base frame 14, and wherein the prongs 442 are bent in an upward direction to engage the housing bottom panels ofthe freadle assemblies 12 along the bottoms thereof. The freadle assemblies 12 are shown in an exaggerated lifted position so that the flat spring 428 and its bent prongs 442 are more clearly visible. These prongs 442 resiliently deform when engaged by their respective freadle assemblies 12 to provide the biasing effect. If a reciprocating linkage is not used, the prongs 442 are in engagement with the freadle assemblies 12 throughout all or substantially all ofthe sfroke thereof. As in the other embodiments ofthe biasing mechanism 428, the ends ofthe prongs 442 may engage the housing 20 directly if it is sturdy and rigid enough, or may engage any suitable strike plate.

Where the term "metallic spring" is used, it will be appreciated that other materials having properties similar to metallic springs may be used.

The position ofthe biasing mechanisms 428 may be made variable to adjust the inclination of the freadle assemblies 12. Illusfratively, the supporting brackets 430 shown in Figs. 54-57 may be made to have a user-adjustable variable length using any suitable mechanism such as a peg-in-hole mechanism or a turnbuckle mechanism. The torsion spring 428 of Fig. 58 and the flat spring 428 with raised prongs 442 of Fig. 59 may be mounted on a sub-frame whose position relative to the base frame 14 may be adjusted by the user.

It should be noted that such adjustment ofthe position ofthe sub-frame would also vary the biasing resistance force. The closer the spring member 428 is moved to the pivot point ofthe treadle assemblies 12, the smaller the biasing force will be, due to reduced leverage. Fig. 53: Brake-Based Dampening Assembly

Fig. 53 shows an example of a dampening assembly 444 that employs a brake 446 for the dampening effect. The brake 446 provides resistance to the rotation of an attached brake pulley 448. The assembly 444 includes an elongated dampening belt 450 that runs from the freadle assemblies 12 to the brake pulley 448 through a system of pulleys 452 in order to fransfer the rotational resistance of the brake pulley 448 to the up and down motion of the freadle assemblies 12. Preferably reciprocation ofthe treadle is coordinated by an interconnection assembly.

An illusfrative system of pulleys 452 is shown in Fig. 53. A first end ofthe dampening belt 450 is attached to a freadle assembly 12 at a point distant from the pivot axis 330 ofthe freadle assembly 12. The more distant the attachment point from the pivot axis 330, the greater the leverage that is realized. A first end of the dampening belt 450 is attached to the right treadle assembly 12. The dampening belt 450 then runs through pulley 552A to change direction by about 90 degrees, from generally vertical to generally horizontal and within the general plane ofthe base frame 14. The dampening belt 450 next runs through pulley 452B rotatably supported with a one-way bearing, which is mounted on a shaft 454 that connects to a first side ofthe differential freewheel 448. Pulley 452B changes the direction ofthe dampening belt 450 about 180 degrees so that the dampening belt 450 remains within the general plane ofthe base frame 14. The dampening belt 450 is twisted about 90 degrees and is run through pulley 452C, which changes the direction of the belt 450 by about 90 degrees so that it traverses the base frame 14 and is run through pulley 452D on the opposite side. Pulley 452D changes the direction ofthe belt 450 by about 90 degrees, and the belt 450 is then twisted about 90 degrees and runs through pulley 450E, which is also rotatably supported with a oneway bearing. Pulley 450E is mounted on a shaft 454 that connects to a second side ofthe differential freewheel 448. Pulley 452E changes direction ofthe dampening belt 450 about 180 degrees so that the dampening belt 450 remains within the general plane of the base frame 14 and is directed to pulley 452F. The dampening belt 450 then runs through pulley 452F to change direction by about 90 degrees, from generally horizontal and within the general plane ofthe base frame 14 to generally vertical. The second end ofthe dampening belt 450 is attached to the left freadle assembly 12 at a point distant from the pivot axis 330 of freadle assembly 12.

When pulley 452E is turned counterclockwise (as viewed from the left side ofthe base frame 14) by an upward movement ofthe left freadle assembly 12, the freewheel engages 448 so that the brake 446 is turned via the brake belt 456 and a pulley 458 mounted on the brake 446 to assert a dampening force in opposition to the upward movement ofthe left freadle assembly 12. An upward movement of the left freadle assembly 12 turns pulley 452B cloclcwise (when viewed from the same point, i.e., the left side ofthe base frame 14) by pulling the dampening belt 450. The clockwise rotation of pulley 452B does not engage the freewheel 448 because the one-way bearing ofthe differential freewheel 448 is engaged only by counter clockwise rotation as viewed from the left side ofthe frame 14. It will be appreciated that the various locations ofthe pulleys in the pulley system of Fig. 53 are not critical. The purpose ofthe pulley system is to transfer the generally vertical motion ofthe treadle assemblies 12 to a brake 446 through a differential freewheel 448. Hence, any pulley system that is able to transfer the generally vertical motion ofthe freadle assemblies 12 to a differential freewheel 448 may be used. It is also advantageous, but not necessary, that as much ofthe dampening belt length as possible be within the general plane ofthe base frame 14, so that it does not interfere with the aesthetics and operation ofthe exercise machine 10.

To accommodate various bias positions (inclinations), the length ofthe dampening belt 450 may be made variable. This may be achieved in a variety of different ways. In one technique, a spooling mechanism is placed at the attachment point in one or both ofthe freadle assemblies 12. The bias and spool settings are adjusted until the desired inclination is achieved with no slack in the dampening belt 450. The spool adjustment may be manual or motor driven under confrol from the user console. In another technique, pulleys 452C and 452D are mounted on a moveable sub-frame. The bias and sub-frame position settings are adjusted until the desired inclination is achieved with no slack in the dampening belt 450. The sub-frame position adjustment may be manual or motor driven under confrol from the user console. A spring may also be used to tension the sub-frame in order to take slack out ofthe dampening belt 450, although some ofthe dampening force may be lost in tensioning the spring.

The brake-based dampening 444 assembly operates as follows. As the user steps down on, say, the belt 18 of freadle assembly 12 so that his foot frictionally engages the belt 18, the left treadle assembly 12 pivots in a downward direction about its pivot axis 330. This has no significant effect on the dampening belt 450, which does not compress. However, as the user steps down on the left freadle assembly 12 he unweights the right freadle assembly 12, which begins to pivot in an upward direction about its pivot axis 330 due to the action ofthe interconnecting device (not shown, but typically a reciprocating linkage such as the rocker arm discussed elsewhere in the specification). The interconnecting device converts the downward force ofthe user's weighted foot on the left freadle assembly 12 to an upward force on the right freadle assembly 12. As the right treadle assembly 12 rises, it pulls the dampening belt 450, which in turn rotates pulley 452B counterclockwise such that the differential freewheel 448 engages. The differential freewheel 448 is coupled to the brake pulley 458 by the brake belt 458, so that the brake 446 asserts a dampening force on the movement ofthe right treadle assembly 12. This dampening force opposes the upward force on the right freadle assembly 12, which in effect dampens the downward movement of the left freadle assembly 12 through the reciprocating linkage.

Next, the user steps on the belt 18 ofthe right freadle assembly 12 so that his foot frictionally engages the belt 18. The right freadle assembly 12 now pivots in a downward direction about its pivot axis 330. As the user steps down on the right freadle assembly 12 he unweights the left freadle assembly 12, which begins to pivot in an upward direction about its pivot axis 330 due to the action of the interconnection device. The interconnection device converts the downward force ofthe user's weighted foot on the right freadle assembly 12 to an upward force on the left treadle assembly 12. As the left treadle assembly 12 rises, it pulls the dampening belt 450, which in turn rotates pulley 452E counterclockwise to engage the differential freewheel 448 so that the brake 446 asserts a dampening force on the movement ofthe left treadle assembly 12. This dampening force opposes the upward force on the left freadle assembly 12, which in effect dampens the downward movement ofthe right freadle assembly 12 through the interconnecting device. It will be appreciated that in this embodiment, the brake 446 need turn in only one direction.

In a variation ofthe embodiment of Fig. 53, two dampening belts 450 are used instead of one continuous belt 450. With reference to Fig. 53, the section of belt 450 between pulleys 452C and 452D is eliminated, and pulleys 452C and 452D are replaced with take-up reels, springs, or other such devices. As the left treadle assembly 12 moves in an upward direction in this variation, the attached dampening belt 450 is drawn from the take-up reel or drawn as the spring stretches so that pulley 452E turns in a counterclockwise direction, causing the differential freewheel 448 to engage so that the brake 446 asserts a dampening force on the movement ofthe left treadle assembly 12. As this is occurring, the right treadle assembly 12 is moving in a downward direction, which tends to cause slackening in the dampening belt 450 that is attached to the right freadle assembly 12. The slack is taken up by the take-up reel or spring. Since the pulley 452B is rotated clockwise, the freewheel 448 does not engage as a result ofthe rotation ofthe pulley 452B.

The differential freewheel 448 is eliminated in the following variation (not shown) of Fig. DC5, which uses a bi-directional brake 446 and a single continuous dampening belt 450. Either the shaft 454 from pulley 452E or the shaft from pulley 452B of Fig. 53 is retained, but not both. Assuming the shaft 454 from pulley 452E is retained, a brake pulley 448 is mounted on the shaft 454 from pulley 452E, and the brake belt 456 of Fig. 53 runs through the brake pulley 448. If desired, the brake 446 may be designed to be mounted directly to the shaft 454 from the pulley 452E. Otherwise, this variation is identical to the Fig. 53 embodiment. In operation, upward movement of either freadle assembly is coupled to the brake 446 due to rotation of pulley 452E.

In another variation ofthe embodiment of Fig. 53, the differential freewheel 448 may be eliminated and two brakes 446 are used, one with pulley 452E and the other with pulley 452B. A single continuous dampening belt 450 may be used in this variation, or two separate dampening belts 450 may be used in this variation.

The term "continuous belt" refers to the structural continuity ofthe belt 450, and not to whether the materials in the belt 450 are homogeneous. An example of a continuous belt 450 is a belt having three sections, the end sections being of flat material and the middle section being a tensioning device such as a spring or a variable length rod such as a turnbuckle. The tension device or variable length rod are useful in conjunction with a biasing device to set the inclination ofthe treadle assemblies 12 while avoiding slack in the dampening belt 450. Although a flat belt is advantageous, the belt is not limited to a flat form and may be any desired shape with any desired surface finish, texture, or features such as corrugation and the like.

With reference to the brake embodiment of Fig. 53, a flywheel may be substituted for the brake 446 and brake pulley 458. The other components would remain the same, except that the brake 446 and brake pulley 458 would be replaced by the flywheel. As the user built up speed, the dampening effect supplied by the flywheel would be reduced by the conserved momentum ofthe fly wheel. If a differential fly wheel is used, it could be mounted on the split shaft 454 connecting pulleys 352B and 352E, and the brake belt 450 and differential free wheel 448 could also be eliminated. Fig. 60: Cushioning Mechanisms for Exercise Machine

Fig. 60 illustrates one embodiment of a cushioning mechanism 154 to cushion the impact that can occur if one ofthe freadle assemblies 12 bottoms out at the bottom of its fravel. This can occur as the user relaxes his pace at the end ofthe workout, and the left and right freadle assemblies 12 are pushed down by the weight ofthe user towards the base frame or the floor. Bottoming out may also occur during a workout ifthe biasing force is not properly set. The exercise machine 10 therefore preferably includes a mechanism to absorb some ofthe force ofthe impact ofthe treadle assemblies 12, to both cushion the user and to avoid damage to the exercise machine 10 or the underlying floor.

The cushioning mechanism 154 of Fig. 60 uses a hard plastic protrusion 160 from a mounting 155 bracket that extends beyond the width ofthe belt 18 ofthe treadle assembly 12 and that has two upward-extending flanges 156 that couple to the internal side frame members 54, 56 ofthe treadle assembly 12. A soft rubber bumper 164 is coupled to the base frame 14, either directly or by a bracket, and is located so that it is engaged by the plastic protrusion 160 as the freadle assembly 12 approaches a bottoming out condition. The soft rubber bumper 164 resiliently deforms when contacted by the hard rubber protrusion 160 to provide the cushioning effect. The hard and resilient portions 160, 164 ofthe cushioning mechanism 154 could be reversed such that a resilient protrusion 164 is provided on the mounting bracket 155, and a relatively harder bumper 160 is provided on the frame 14. Figs. 61A-61B: Bottom Drive Exercise Machine

The bottom drive exercise machine 10 of Figs. 61A and 61B has two freadle assemblies 12, a right assembly 12 and a left assembly 12. Each ofthe treadle assemblies 12 is essentially a separate treadmill with its own tread belt 18, deck 26, and front, rear and offset rollers 28, 30, 31. Although each ofthe freadle assemblies 12 may be driven by its own motor 88 if desired, advantageously both freadle assemblies 12 are driven by a common driveshaft and the same motor. This assures that the belts travel at the same speed. If desired, a single drive roller for both ofthe treadle assemblies 12 may be used instead of separate drive rollers for each. The treadle assemblies 12 also are interconnected to provide a balanced relationship between the right and left sides during a workout and to provide some additional cushioning. The balanced relationship may be achieved in a variety of ways, including by a reciprocating linkage such as any ofthe rocker arm assemblies described in this document. The exercise machine 10 may be operated in a freadmill mode by locking the left and right freadle assemblies 12 together at a desired incline such as 10% to get a traditional freadmill workout, or may be operated in a stepper mode by maintaining the belts 18 stationary (motor off). With a few exceptions, the same arrangements of components as used in the rear drive embodiment described elsewhere in this document are generally suitable for the bottom drive embodiment of Fig. 61A.

The freadle assemblies 12 are pivotally coupled to the base frame 14 ofthe exercise machine 10 along a common axis 330, although a common axis is not required. The freadle assemblies 12 pivot about their axes 330. Illusfratively, the pivot axes 330 ofthe freadle assemblies 12 are the axes ofthe drive shafts 82 that drive the respective drive rollers ofthe freadle assemblies 12. The ends ofthe drive shaft 82 rest in bearings in each ofthe pivot brackets 460, which project from the base frame 14. In one embodiment, the driver roller is the offset roller 31. In other embodiments, the drive roller is the front roller 28 or the rear roller 30. In each ofthe freadle assemblies 12, the offset roller 31 and the front and rear rollers 28, 30 form an inverted triangle, with the front and rear rollers 28, 30 delineating the base ofthe triangle and the offset roller 31 the apex. The height ofthe triangle as peφendicularly measured from the base to the apex may be quite large, as shown in Fig. 6 IB, or quite small by bringing the offset roller 31 nearly in line with the front and rear rollers 28, 30.

The pivot axes 330 ofthe freadle assemblies 12 may be offset from the drive shaft 82 if desired, with other structures supporting the pivoting action. The pivot 330 may be fixed as shown, or may be variable. Different mechanisms may be used for establishing variable pivot points, including mounting the right and left freadle assemblies 12 and the drive shaft 82 in a sub-frame, and providing a variable position locking mechanism between the sub-frame and the base frame 14. An illusfrative variable position locking mechanism is an array of holes in the pivot bracket 460 and a spring-loaded peg mechanism in the sub-frame. Others includes notches, clamps and ledges.

To operate the exercise machine 10 of Fig. 61 A in a normal mode, the user adjusts the dampening effect and the biasing effect as desired, steps upon right and left side foot support platforms (not shown in Fig. 61 A but described elsewhere in this document), adjusts the workout profile on the console as desired (the respective belts 18 ofthe right and left freadle assemblies 12 begin to move), and steps from the right and left foot support platforms onto the right and left belts 18, respectively. The preferred step area in the Fig. 61 A embodiment is the area ofthe deck between the front roller 28 and a line on the deck 26 intersected by an imaginary peφendicular plane extending from the deck 26 through the pivot axis 330 (see Fig. 6 IB). The weight ofthe user will thus tend to pivot the deck 26 about the pivot axis 330.

With reference to Fig. 61, assume the user is walking or running in the direction of roller 28 (the arrow shows the movement ofthe belt 18, which is in a direction opposite the direction the user has talcen). In normal mode operation as shown in Fig. 61B, the user has shifted his weight from the right freadle assembly 12A (which has been carried along the right freadle assembly 12A by the moving belt 18) to the left freadle assembly 12B. The force exerted on the left freadle assembly 12B is opposed by the dampening resistance, which may be speed dependent and increases with speed, and the biasing force, which is dependent on the attachment position or biasing force ofthe biasing device. The right freadle assembly 12A begins to rise because the foot thereon has been unweighted and because the downward force on the left freadle assembly 12B is being fransferred as an upward force to the right freadle 12A through the reciprocating linkage (not shown). Next, the foot on right freadle 12A becomes fully unweighted as it is lifted and moved from the rear ofthe step area ofthe treadle assembly 12A toward the front ofthe step area ofthe freadle assembly 12 A. Meanwhile, the full weighted foot on the left treadle 12B is carried toward the rear ofthe deck ofthe freadle assembly 12B with the moving belt 18, and the inclination ofthe left freadle assembly 12B decreases due to the weight while the inclination ofthe right freadle assembly 12A increases due to the biasing force and the fransferred force. At a slow belt speed (slow pace), the freadle assemblies 12 fravel through a greater arc range that at high belt speeds (fast pace), all else being equal.

If desired, the belts 18 of the freadle assemblies 12 may be run in reverse. If desired, either of the front and rear rollers 28, 30 may be made into a drive roller. Figs. 62A-62C: Deckless Exercise Machine

The freadle assembly shown in Fig. 62A differs from those described and shown elsewhere herein in that no deck or deck suspension is present.

Decks 26 are common in standard treadmills, wherein they provide stability and a degree of cushioning to contribute to the comfort ofthe legs and feet with prolonged use. To provide additional cushioning for the legs, feet and back, treadmills may use a suspension directly under the deck, hi one approach, rubber bushings are used under a flexible deck 26. Traditional freadmill belts 18 typically have walking/running surfaces ranging from 17" to 22" wide and 51" to 61" long. Figs. 27- 32 illusfrate deck-type suspensions for freadle assemblies 12 according to the present invention.

A deckless freadmill known as the Orbiter™ treadmill is available from Orbiter Treadmills of Highlands, TX. As stated in a testimonial in the product literature, "Sold largely to medical rehab centers, the Orbiter™ freadmill has a rubbery, suspended running surface that stretches when your foot lands on it. (It felt like I was running on a trampoline.)" While the Orbiter freadmill may be effective in absorbing shock and providing an effective workout, the stretching may cause some users to feel a sense of instability. The surface length of the belt is 56" and the width is 20".

The freadle assemblies 12 shown in Figs. 62 A, 62B, 62C have no deck and no underlying suspension, which provides shock absorbing properties to the step area 462. Good stability is realized in the freadle assemblies because ofthe relatively small size ofthe step area 462, illustratively 40 inches long and 8 inches wide in the rear drive machine shown in Figs. 62 A, 62B, and 62C. Overall stability may be improved by using reinforced belt material. Transverse stability may be improved in a variety of ways, such as by reinforcing the edges ofthe belt 18 with a fiber bead or a steel cable. Additionally, the rollers 28, 30 over which the belt 18 passes may be provided with grooves to receive the reinforced edges and maintain the belt 18 in a degree of transverse tension in the area ofthe rollers, and additional grooved wheels or channels may be provided along both edges ofthe step area 462 to engage the reinforced edges ofthe belt 18 and maintain the belt 18 in a degree of transverse tension throughout the step area 462.

The freadle assemblies 12 may be provided with decks 26 that can be locked in place just under the belt 18 in the step area to provide a stable and reasonably well cushioned walking/running surface for a normal workout, or may be parked in a position away from the step area to provide a low impact wallcing/running surface particular well suited for persons who are unable to tolerate the shock associated with a normal workout. The three roller embodiment ofthe movable belt freadle assembly, described in detail elsewhere in this document is particularly well suited for such a displaceable deck 26 because ofthe ample volume existing within the treadle assembly for the necessary mechanisms.

The front 22 ofthe right freadle assembly 12A and the front 22 ofthe left freadle assembly 12B move up and down opposite from each other by pivoting about an axis 330 positioned at their respective rear ends 24. As the freadle frame side tubes located on the inside ofthe adjacent right and left freadle assemblies 12 pass by each other during this movement, a gap or space alternately opens and closes. To help keep this gap from allowing undesired access to the internal framework of the freadles 12 and the base frame 14, such as debris and sweat, a shroud or similar structure is used to eliminate the gap. The shrouds described below can also attach to the framework of the exercise apparatus so as to not interfere with motion of treadles. Figs. 63A-63X: Dual Treadle/Treadmill Exercise Device With Various Shroud Arrangements

As shown in Fig. 63A, the exercise apparatus is equipped with a base shroud 464 covering the base frame. The base shroud 464 includes a front portion 466, a right side portion 468, a left side portion 470, a rear portion 472, and a top portion 474. The top portion 474 ofthe base shroud 464 is defined by a front top surface 476, a left top surface 478, a right top surface 480, and a rear top surface 482. Treadle apertures 484 located in the top portion 474 are separated by a top surface center strip 486 connected with the front top surface 476 and the rear top surface 482. As shown in Fig. 63A, the right upright 42 and left upright 40 are connected to the base frame in conjunction with the right side portion 468 and the left side portion 470 ofthe base shroud.

The base shroud 464 can be made from molded plastic, fiberglass, aluminum, or any other suitable material, and can be rigid, flexible or any combination. The base shroud can also be manufactured in separate pieces to be assembled using screws, snaps, fasteners, and the like. Considerations as to how the exercise apparatus is to be assembled or disassembled and shipped may be talcen into account in determining the manner in which the base shroud may be manufactured. In some embodiments, the base shroud can be manufactured as an integral piece.

As depicted in Fig. 63 A, the right freadle assembly 12A, shown in the upward position, and the left freadle assembly 12B, shown in the downward position, are each equipped with a treadle shroud assembly 488 that moves with the freadle assemblies 12 when the exercise device is in use. The freadle shroud assemblies 488 can be made from plastic, fiber glass, aluminum, or any other suitable material, and can be secured to the freadle assemblies using various techniques such as screws, snaps, fasteners, and the like. The treadle shroud assemblies can also be secured to the treadle assemblies using adhesives or hook and loop fasteners. The freadle shroud assembly 488 includes an outside side shield 490, an inside side shield 492, and a front side shield 494. The outside side shield 490 and the inside side shield 492 are connected to the freadle assemblies 12 adjacent the freadle side tubes and spanning the length ofthe freadle assemblies. The front side shield 494 is connected with the outside side shield 490 and the inside side shield 492 and spans the length ofthe front roller on the treadle assembly. An inside shield edge 496 is defined by the intersection ofthe inside side shield 492 and the front side shield 494, and an outside shield edge 498 is defined by the intersection ofthe outside side shield 490 and the front side shield 494. The inside side shield 492 can be generally triangular in shape and defined by a top shield edge 500, a bottom side shield edge (HIDDEN), and the inside edge 496. The outside side shield edge 498 can also be generally triangular in shape and defined by the top side shield edge 500, the bottom side shield edge (HIDDEN), and the outside edge 498.

As shown in Fig. 63A, the freadle shroud assembly 488 is sized such that when the right freadle assembly 12A is located in the upward position, the area between the right treadle assembly 12A and top portion 474 ofthe base shroud 464 is covered by the front side shield 494 and the outside side shield 490. In this position, the area between the right freadle assembly 12A and the left treadle assembly 12B is covered by the inside side shield 492 ofthe right freadle 12 A. Opposite of what is shown in Fig. 63A, when the left freadle assembly 12B is located in the upward position, the area between the left freadle assembly 12B and top portion 474 ofthe base shroud 464 is covered by the front side shield 494 and the outside side shield 490. In this position, the area between the left treadle assembly 12B and the right freadle assembly 12A is covered by the inside side shield 492 ofthe left treadle 12B.

As the right 12A or left freadle assembly 12B pivots toward the downward position, the treadle shroud assembly 488 passes through the freadle aperture 484 located in the top portion 474 of the base shroud 464. In order to close the gap between the base shroud 464 and the freadle shroud assemblies 12, the inside side shields 492 are positioned close to and adjacent the center strip 486 in the top portion 474 ofthe base shroud 464, as shown in Fig. 63 A. Similarly, the outside side shields 490 are positioned close to and adjacent the left top surface 478 and the right top surface 480. The front side shields 494 are also positioned close to and adjacent the front top surface 476. Because the treadle assemblies 12 pivot up and down in an arcuate path, the inside shield edge 496, the outside shield edge 498, and the front side shield 494 can be arcuately shaped to keep the front side shield 494 close to the front top surface 476 ofthe base shroud 464 as the freadle assemblies 12 pivot up and down. The present invention utilizing freadle shroud assemblies 488 similar to that depicted in Fig. 63 A can also be used with various different embodiments ofthe base shroud. For example, Fig. 63B depicts the exercise apparatus utilizing an alternative base shroud design 464 that has only one freadle aperture 484. The freadle assemblies 12 are shown in pivot positions at a point between the upward and downward positions to better illusfrate the various components ofthe treadle shroud assemblies. As shown in Fig. 63B, the treadle assemblies 12 are not separated by a center strip in the top portion, so the treadle assemblies are located on the exercise apparatus such that the inside side shields 492 are adjacent to each other. hi another scenario ofthe present invention, the freadle assemblies 12 are configured on the exercise apparatus such that the front side shield can be eliminated, as shown in Figs. 63C and 63D. The right and left treadle assemblies 12 are both depicted in the flush, mid point position, and the front portion 466 ofthe base shroud 464 is configured so that no gap exists between either treadle assembly and the front top surface 476 ofthe base shroud 464. As previously described with reference to Fig. 63A, when one freadle assembly is in the upward position and the other freadle assembly is in the downward position, the area between the bottom of one freadle assembly and the top ofthe other freadle assembly is covered by the inside side shield 496 ofthe freadle in the upper position. The outside side shields 490 shown in Figs. 63C and 63D are also equipped with a plurality of shield tracks 502 that slidingly engage shield tracks (HIDDEN) on the inside ofthe left 470 and right portions 468 ofthe base shroud 464. Because the freadle assemblies 12 pivot up and down in an arcuate path, the shield tracks 502 can also be arcuate. The shield tracks 502 can add to the sturdiness ofthe exercise apparatus as a user exerts forces while running or walking on the freadle assemblies.

Figs. 63E - 63X show freadle shroud assemblies 488 in various other views and incoφorated in alternative embodiments ofthe present invention. Figs. 64A-64B: Dual Treadle with Flexible Shield

Figs. 64A and 64B depict an alternative embodiment ofthe treadle shroud assembly 488^'. Unlike the base shroud 464 depicted in Fig. 63A, the base shroud 464' shown in Figs. 64A and 64B does not have right side and left portions forward ofthe right 42 and left uprights 40. Instead of having the front portion, the base shroud shown in Figs. 64A and 64B includes a bottom middle portion 504 connected with the left 40 and right uprights 42. Because the base shroud 464' has no front portion and no front top surface, there is no exposed area between the freadle assemblies 12 and the front top surface ofthe base shroud 464^" when the treadle assemblies pivot up and down. Therefore, there is no need to have front side shields included as part ofthe freadle shroud assemblies.

As shown in Figs. 64A and 64B, the outside side shields 490' ofthe freadle shroud assemblies 488' are generally rectangular in shape. The outside side shields 490' are tall enough such that there is no gap between the bottom shield edge 506 ofthe outside side shield 490' and the left top surface 478' ofthe base shroud 464' when the treadle 12 is in the upward position. A flexible shield 510 is connected with the bottom shield edge 508 on each inside shield 492'. As shown in Fig. 64A, the right freadle assembly 12A is in the upward position and the left freadle assembly 12B is in the downward position. The area between the right freadle assembly 12A and the left freadle assembly 12B is covered by the inside side shield 492' and the flexible shield 510. Fig. 64B shows the opposite positioning ofthe freadle assemblies in Fig. 64A. In Fig. 64B, the left freadle assembly is located in the upward position and the right treadle assembly 12A is located in the downward position. Again, the area between the left freadle assembly 12B and the right freadle assembly 12A is covered by the inside side shield 492^' and the flexible shield 510. As shown in Fig. 64A, the shields or shrouds do not have to cover the entire open gap or space.

It should be understood that the treadle shroud assemblies 488' shown in Figs. 64 A and 64B can work with other base shroud configurations. In another example, ifthe base shroud includes the front portion and the front top surface as described with reference to Fig. 63A, the freadle shroud assemblies as described in Figs. 64A and 64B can include front shields, hi another scenario where the base shroud includes the center strip and two freadle apertures as previously described with reference to Fig. 63A, the flexible shields could be connected with the center strip and the freadle assemblies. Flexible shields could also connect with the freadle assemblies and the right and left top surfaces of the base shroud. Fig. 65

An alternative embodiment ofthe present invention is depicted in Fig. 66. The left side 470" and right side portions 468" ofthe base shroud 464" do not extend forward ofthe right 42 and left uprights 40. Therefore, unlike the freadle assemblies depicted in Fig. 63A, the freadle assemblies 12 are not enclosed in the front the portion of the base shroud. As shown in Fig. 65, the freadle assemblies 12 are located on the exercise apparatus such that the inside side shields 492" are adjacent to each other. The inside side shields 492" are also sized so that there is no gap between the bottom shield edge 506" of one treadle assembly and the freadle deck 26 ofthe other freadle assembly when one freadle assembly is in the upward position and the other treadle assembly is in the downward position. The outside side shield 490" (having a generally rectangular shape), the front side shield 494", and a bottom side shield 512 partially enclose the belt 18 on the freadle assembly 12 as it passes under the freadle deck 26. The front side shield 494" can also be removable to allow access to the freadle belt 18. The inside shield 492" can also have a generally triangular shape. Figs. 66A-66C: Alternative Shrouding arrangements

In Fig. 66A, an alternative embodiment of the base shroud 464" is shown having the front portion 466" split into two sections, a right front portion 514 and a left front portion 516. As shown in Fig. 66 A, the left front portion 516 and the left portion 470" are partially enclosed by the freadle shroud assembly 488" when the left treadle assembly 12B is in the downward position. Similarly, the right front portion 514 and the right portion 468" are partially enclosed by the right treadle shroud assembly 488" when the right treadle assembly 12A is in the downward position. As shown in Fig. 66A, when the right treadle assembly 12A is located in the upward position, most of the right front portion 514 and the right portion 468" are exposed. However, there is no gap between the freadle shroud assembly 488" and the base shroud 464" in this position. Similarly, when the left freadle assembly 12B is located in the upward position, most of the left front portion 516 and the left portion 470" are exposed.

As shown in Fig. 66A, the right front portion 514 and the left front portion 516 can also be configured with shield tracks 502". The shield tracks 502" slidingly engage opposing shield tracks (not shown) on the inside ofthe front side shield 514, which help reduce any side to side movement of the treadle assemblies 12 when the exercise apparatus is in use. The treadle shroud assembly configuration shown in Fig. 66A can also be used with alternative configurations ofthe base shroud 464". For example, Fig. 66B depicts an embodiment similar to that shown in Fig. 66A, except the base shroud 464" in Fig. 66 includes the rear top surface 482". In another scenario depicted in Fig. 66C, an alternative embodiment similar to that shown in Fig. 66B does not include shield tracks 502". Figs. 67A-67C: Alternative Shroud Arrangements

A further representation ofthe present invention is depicted in Figs. 67A and 67B. The base shroud 464" shown in Figs. 67A and 67B further includes a right center portion 518 and a left center portion 520 connected with the right front portion 514 and the left front portion 516, respectively. The right 518 and left center portions 520 can also be substantially mirror images of the right 418" and left portions 470". As shown in Figs. 67A and 67B, accordion-pleated shields 526 are connected with the freadle shroud assemblies 488" and the base shroud 464". More particularly, a first accordion-pleated shield 526A is connected with the base shroud 464" at a base shroud top edge 524 located on top ofthe right side portion 468", the right front portion 574, and the right center portion 518. The first accordion-pleated shield 526Ais also connected with the freadle shroud assembly 588" underneath a top side shield 522 connected with the right treadle assembly 12A. Similarly, a second accordion-pleated shield 526B is connected with the base shroud 464" at the base shroud top edge 524 located on top of he left side portion 470", the left front portion 516, and the left center portion 520. The second accordion-pleated shield 526B is also connected with the treadle shroud assembly 488" underneath the top side shield 522 connected with the left freadle assembly 12B.

The left freadle assembly 12B is depicted in the downward position and the right freadle assembly 12A is depicted in the upward position in Fig. 67A. The freadle shroud assembly 488" connected with the left treadle assembly 12B at least partially encloses the left portion 470", the left front portion 516, and the left center portion 520 ofthe base shroud 464". Likewise, the freadle shroud assembly 488" connected with the right freadle assembly 12A at least partially encloses the right portion 468, the right front portion 514, and the right center portion 518 of the base shroud 464". As shown in Fig. 67A, when the right freadle assembly 12A is in the upward position, the accordion- pleated shield 526 encloses the space between the freadle shroud assembly 488" and the base shroud 464". As the right freadle assembly moves to the downward position, the accordion-pleated shield 526 folds and collapses on the pleats to become enclosed under the freadle shroud assembly 488". As the left treadle assembly 12B moves to the upward position, the accordion-pleated shield 526 unfolds on the pleats and until it is exposed. As shown in Fig. 67B, the right freadle assembly 12A is depicted in the downward position and the left freadle assembly 12B is depicted in the upward position. As shown in Figs. 67A and 67B, when the freadle assemblies 12 are in the upward positions, the inside 492" and outside side shields 490" maintain partial coverage ofthe base shroud 464". Therefore, in certain embodiments, the accordion-pleated shield need not be utilized on the entire length ofthe freadle shroud assemblies. Fig. 67C shows the shroud assemblies 488" with accordion-pleated shields 526 utilized with an alternative embodiment ofthe base shroud 464". Figs. 68A-69B: Accordion or Folding Shroud Arrangement

Figs. 68A and 68B show another scenario ofthe present invention where the area between the freadle assemblies 12 and base shroud 464" are covered with accordion-pleated shrouds 526. More particularly, a first accordion-pleated shroud 526A is connected with the left top surface 478" and the front top surface 476" ofthe base shroud 464". The first accordion-pleated shroud 526A is also connected underneath the left freadle assembly 12B. Similarly, a second accordion-pleated shroud 526B is connected with the right top surface 480" and the front top surface 476" ofthe base shroud 464". The second accordion-pleated shroud 526B is also connected underneath the right freadle assembly 12A. The right and left freadle assemblies 12 are separated by a center shield 528. The center shield 528 can be connected with the base shroud 464" near the rear top surface 480".

As shown in Fig. 68A, the right treadle assembly 12A is in the upward position and the left freadle assembly 12B is in the downward position. The center shield 528 covers the area between the bottom ofthe right freadle assembly 12A and the top ofthe left treadle assembly 12B. As the right freadle assembly 12A moves to the downward position, the accordion-pleated shroud 526B folds and collapses on the pleats under the freadle shroud assembly 12A. As the left treadle assembly 12B moves to the upward position, the accordion-pleated shroud 526A unfolds on the pleats and until it is extended. As shown in Fig. 68B, the right freadle assembly 12A is depicted in the downward position and the left freadle assembly 12B is depicted in the upward position. Fig. 68C shows the accordion- pleated shroud assemblies 526 utilized with an alternative embodiment ofthe base shroud 464". The use of the accordion-pleated shrouds is not limited to that which is depicted herein. For example, other embodiments ofthe present invention could utilize accordion-pleated material on the front and outsides ofthe freadle assemblies while utilizing hard inside shields, or in any other combination of hard shields and accordion-pleated material thereof.

Other types of material can be used besides the accordion-pleated material on the embodiment depicted in Fig. 68A. For example, as shown Figs. 69A and 69B, a multi-fold material is utilized on the treadle shroud. The multi-fold material is configured with various patterned folds in the material. When either treadle assembly 12 is in the downward position, the multi-fold freadle shroud 530 collapses on patterned or unpatterned folds or pleats in the material, similar to the accordion-pleated material. When either freadle assembly 12 is in the upward position, the multi-fold freadle shroud 530 unfolds on the patterned folds or pleats and until it is extended. It should be understood that the present invention as described above is not limited to the use of accordion-pleated and multi-fold materials. For instance, embodiments ofthe present invention could utilize stretchable fabric such as rubber, elastic, Lycra®, and the like. Figs. 70A-70C: Shielding Arrangements

Figs. 70A to 70C depict how various embodiments ofthe present invention utilizing the center shield 528 can secure it to the frame 14. As shown in Figs. 70A and 70B, the center shield 528 is supported on the frame 14 by a center drive bracket 532 and a spring 534. As shown in Fig. 70C, a rear portion 536 ofthe center shield 528 is pivotally supported by a pivot axle 538 on the center drive bracket 532. A front portion 540 ofthe center shield 528 is supported by the spring 534. Therefore, when force is exerted on the top ofthe center shield 528 (i.e. when stepped on during use), center shield will pivot down toward the frame 14 as the spring 534 is compressed. The spring 534 restores it to the upright position. This configuration lets the center shield 528 move out ofthe way when stepped on to avoid interfering with the user's stride. In this embodiment, the top ofthe center shield 528, when in the upper position, can be flush with the top of either freadle 12 in the upper position, or can be slightly below flush, or can be above-flush as shown.

Alternative embodiments ofthe present invention could utilize a center shroud assembly instead ofthe center shield between the treadle assemblies. The center shroud assembly could include a left center wall, a right center wall, a top center surface, and a front center surface. The front center surface extending upward from the top portion ofthe base shroud. The left center wall and right center wall being generally triangular in shape and separated by the width ofthe top center surface. The top center surface extending from the front center surface toward the rear portion of the base shroud until it intersects with the top portion.

As the exercise apparatus is used over time, it may be necessary to replace the freadle belt 18 after it wears out. On other occasions, the user may desire to change the length ofthe freadle assembly depending on how he or she wants to use the exercise apparatus (i.e. for walking or running). An adjustable length freadle assembly 12 is depicted in Fig. 71 that makes it easier for a user to replace a worn freadle belt and to adjust the length ofthe freadle assembly. Moreover, by reducing the length ofthe freadle assembly, the overall length ofthe device may be reduced for shipping. With a reduced device, a smaller box may be used, which is less expensive and easier to handle.

As shown in Fig. 71, the freadle assembly 12 includes a treadle frame 542 having a left forward side tube 544, a left rearward side tube 546, a right forward side tube 548, and a right rearward side tube 550, together making up the frame. The left forward side tube 544 and the right forward side tube 548 are connected with the front roller 28. The left rearward side tube 546 and the right rearward side tube 550 are connected with the rear roller 30. The left forward side tube 544 is slidingly engaged with the left rearward side tube 546, and the right forward side tube 548 is slidingly engaged with the right rearward side tube 550, such as by telescoping engagement or other such structure. The side tubes can also engage each other through mating tracks, grooves, and the like. The sliding engagement ofthe side tubes allows a user to move the front roller 28 in a rearward direction toward the rear roller 30, or in a forward direction away from the rear roller 30.

The belt deck 26 on the adjustable length freadle assembly 12 can include a forward belt deck 552, a middle belt deck 554, and a rearward belt deck 556, as shown in Fig. 71. It should be understood that more than one middle deck can be used, and the invention should not be construed to be limited to what is depicted herein. When in use, the freadle belt 18 travels over the upper deck surface 558 ofthe forward belt deck 552, the middle belt deck 554, and the rearward belt deck 556. The left forward side tube 544 and the right forward side tube 548 are connected with the lower deck surface 560 ofthe forward belt deck 552, and the left rearward side tube 546 and the right rearward side tube 550 are connected with the lower deck surface 562 ofthe rearward belt deck 556. The freadle side tubes can be connected with the forward and rearward belt decks using screws, snaps, fasteners, glue, and the like. hi Fig. 71, the middle belt deck 554 is shown as removed from between the forward belt deck 552 and the rearward belt deck 556. When the exercise apparatus is in use, the middle belt deck 554 is located between the forward belt deck 552 and the rearward belt deck 556, so that engagement sides 564 ofthe middle belt deck 554 are in contact with the engagement side 566 ofthe forward belt deck 552 and the engagement side 568 ofthe rearward belt deck 556. The engagement sides ofthe belt decks can include tracks, slots, and/or locking mechanisms to help hold the middle belt deck in position when in use.

Ifthe user desires to replace the freadle belt 18 on the treadle assembly or change the length ofthe treadle assembly, he or she can remove the middle belt deck 554 by sliding it either right or left from under the freadle belt 18 and out from between the forward freadle deck 552 and the rearward treadle deck 556. The user can then move the front roller 28 rearward toward the rear roller 30 until the treadle belt 18 is loose enough to easily remove. The user can then remove the freadle belt from the rollers and install a replacement treadle belt. Ifthe user is changing the length ofthe freadle assembly, the replacement treadle belt will be longer or shorter than the removed freadle belt, hi some embodiments ofthe present invention, the belt length can be adjusted without the need to replace the freadle belt. Once the replacement freadle belt is installed on the rollers, the user then moves the front roller 28 forward to remove slack from the replacement freadle belt. The user then slides the properly sized middle belt deck 554 back into position between the forward belt deck 552 and rearward belt deck 556. For instance, ifthe user is changing the length ofthe freadle assembly, the user can replace the removed middle belt deck 554 with one that is longer or shorter.

As previously stated, various embodiments ofthe present invention can utilize varying numbers of freadle decks that can be secured to the treadle frame in various ways. For example, one embodiment ofthe present invention utilizes only the forward freadle deck and the rearward freadle deck, without the need for the middle treadle deck. In this configuration, the rearward treadle deck can be connected with the freadle frame as previously discussed. However, the forward freadle deck can be removably secured between the rearward deck and a bracket assembly attached to the left forward side tube and the right forward side tube. Removing the forward treadle deck in this configuration can be achieved in a manner similar to that previously discussed with reference to the removal ofthe middle freadle deck. In other embodiments, the forward freadle deck can be connected with the left forward side tube and the right forward side tube, and the rearward freadle deck is removable.

Alternative embodiments ofthe present invention could utilize a center shroud assembly instead ofthe center shield between the freadle assemblies. The center shroud assembly could include a left center wall, a right center wall, a top center surface, and a front center surface. The front center surface extending upward from the top portion ofthe base shroud. The left center wall and right center wall being generally triangular in shape and separated by the width ofthe top center surface. The top center surface extending from the front center surface toward the rear portion ofthe base shroud until it intersects with the top portion. Figs. 72-74: Treadle Locking Mechanism

Figs. 72A-74 display various embodiments of a locking mechanism 702 Generally, the locking mechanism 702 may fix the height of one or both treadles 12, preventing further angular motion. When the locking mechanism 702 is in a fixed position, a portion ofthe locking mechanism interacts with a portion ofthe treadle 12, preventing further freadle movement. The exact nature of each interaction is discussed with specific reference to the figures. Alternately, the treadles' bottom surfaces may rest on a portion ofthe mechanism. This support prevents the freadle or freadles from continuing their up-and-down motion.

Fig. 72A displays a first embodiment of a locking mechanism 702 placed on an exercise device 10, shown in more detail in Fig. 72B.

Turning now to Fig. 72B, an expanded view ofthe first embodiment 702 of a locking mechanism may be seen. In this embodiment, a user may press down on a pedal 704 to lock out the freadles 12. The pedal 704 is attached to a bar 706, which in turn is attached to a pair of locking tabs 708. A bar slot 710 extends through the bar. A pivot 712 runs through the bar slot 710, and is attached on either side ofthe bar slot to a pivot support 714. One or more piano hinges 716 anchor the locking tabs 708 to the main frame 14. Similarly, the pivot support 712 is typically affixed to the main frame 14. In the present embodiment, the locking tabs 708 are connected to the piano hinge 716 by a lock upright 718. Generally, the lock upright and locking tabs form a ninety degree angle, although alternate embodiments may vary this angle. Collectively, the locking tabs 708, lock upright 718, and piano hinge 716 are collectively referred to as the "locking tab structure." 722 A pivot slot 720 is depicted in Fig. 72B and typically used in lieu ofthe bar slot 710, rather than in conjunction therewith. Accordingly, most embodiments 702 include one or the other element, but not both. However, some embodiments may use the bar slot 710 and pivot slot 720 in conjunction with one another.

Fig. 72B shows the locking mechanism 702 in an engaged or locked position. When the locking mechanism is in an unlocked state, the front edge of the locking tabs 708 (i.e., the edge opposite the joinder with the lock upright 718) typically contacts the main frame 14. The pivot 714 is then located at the end ofthe bar slot 710 nearest the locking tab 708 structure.

As the pedal 704 is depressed, the bar 706 generally slidingly rotates around the pivot 714, with the pivot moving along the bar slot 710. Since the locking tab structure 722 is hingedly affixed to the main frame 14, the lock upright 718 may rotate around the piano hinge 716, bringing the locking tabs 708 into alignment with the treadles 12. Further, as the pedal 704 is depressed, the pivot 712 slides along the bar slot's 710 longitudinal axis towards the pedal. This longitudinal motion permits the lock upright 718 rotation just described, h the present embodiment, the lock upright 718 rotates cloclcwise about the piano hinge 716.

As the locking tabs 708 move into an upright position, they may engage a groove or channel (not shown) located along the bottom ofthe freadles 12, either in the bases of the freadles themselves, in the stop blocks 160, or otherwise affixed to the stop brackets 126, 132. The channels may include a snap or spring bracket, or other noise-producing and tab receiving device, at a point near the channel end. When the locking tab 708 engages or pushes the noise-producing device, an audible "click" or other noise is produced. This informs the user that the locking tab 708 is properly seated inside the channel in order to lock out freadle motion. Alternate embodiments may seat the locking tab 708 in a channel or receptacle that makes a noise when receiving the locking tab, but nonetheless securely locking out freadle motion.

The channel (not shown in Fig. 72B) may also include an upright flange or projection oriented peφendicularly to the locking tab 708 travel direction, and projecting far enough across the channel to impact the locking tab as it travels along the channel. Generally, such a projection is sufficiently flexible or deformable to permit the locking tab 708 to continue moving beyond the projection, and is again located near the channel end. The locking tab 708 may include a mating groove located approximately the same distance from the front edge ofthe locking tab as the projection is from the channel end. When the locking tab 708 impacts the projection and/or the projection seats inside the mating groove, the tactile feedback produced may also inform the user that the locking tab is properly seated within the channel. The tactile feedback mechanism just described may be used in conjunction with a noise-producing device.

The channels previously mentioned may be either parallel to the main frame 14, in which case the front edge of the locking tab 708 enters the channel first, or peφendicular to the main frame, in which case the top surface ofthe locking tab enters the channel first. Either variety of feedback mechanism (tactile or noise-producing) may be used with either channel configuration.

Although the locking tabs 708 are shown as flat, planar elements in Fig. 72B, alternate embodiments may curve the tabs, either slightly or more significantly. In such a case, the matching channels on the freadle assembly 12 may be curved as well. A curved locking tab 708 directs downward force against the channels, thus providing additional resistance to a rising freadle. In order to mate with a curved locking tab 708, the channel is generally wider at the tab enfrance, and has a tapering width along the channel cavity.

In the embodiment 702 shown in Fig. 72B, the lock upright 718 rotates clockwise about the piano hinge 716. In an alternate embodiment, the pivot 712 and bar slot 710 may be configured to permit the lock upright 718 to rotate counter-clockwise about the piano hinge 716. In such an embodiment, the pivot positions are reversed along the bar slot 710. That is, while the pedal 704 is in a raised position, the pivot is located at the end ofthe bar slot 710 nearest the pedal. Conversely, when the pedal 704 is depressed, the pivot 712 slides to the end ofthe bar slot 710 nearest the locking tab structure 722. Further, the locking tabs 708 may be reversed in orientation to point towards the pedal 704, in order to engage the treadle 12 channel. Reversal ofthe pivot 712/bar slot 710 and locking tabs 708 may be simultaneously employed in some embodiments, and used separately in others.

In yet another embodiment, the freadle 14 channels may be omitted, hi such an embodiment, the freadles 14 simply rest on the locking tabs 708, preventing further angular motion. When such "resting" embodiments are employed, the locking tabs 708 may be T-shaped in order to provide additional support surface for the treadles 12. Further, the locking tabs 708 may point either towards or away from the pedal 704 when in an engaged position, regardless ofthe direction of rotation ofthe locking tab structure 722. hi further alternate embodiments, the bar slot 710 may be omitted. Ifthe bar slot is omitted, the pivot support 714 may slide along a pivot slot 720 located in the main frame 14 or other supporting structure. Generally, the pivot support 714 slides in the manner previously mentioned with respect to the pivot 712 itself.

Additionally, the locking mechanism 702 shown in Fig. CH1B may be provided with a ratchet mechanism to enable the lockout procedure described above to take place at varying treadle 12 heights.

Although the above embodiment 702 has been discussed as simultaneously locking out both freadles 12, an alternate embodiment may provide a separate pedal 704 and locking tab 708 arrangement for each freadle. In such an embodiment, pressing on a pedal 704 may swing a single locking tab 708 into a locking position, thus interacting with a single treadle 12. The two locking mechanisms 702 may be synchronized, thus locking both freadles 12 at the same angle, or may be independent, permitting each freadle to be locked at a unique angle. Fig. 73 shows an alternate locking mechanism 724. Here, the bar slot 726 is located at the end ofthe bar 728 opposite the pedal 730, rather than along the length ofthe bar. Rather than sliding the pivot 732 along the bar slot 726, the pivot is fixed in a pivot support 734 and thus occupies a fixed position along the length ofthe bar 728. Instead, a wheel rod 736 extends from the surface of a lockout wheel 738 into the bar slot 726. Generally, when the pedal 730 is up (corresponding to a non- locked position), the wheel rod 736 is in a portion ofthe bar slot 726 located closer to the pedal than the opposing bar 729 end. The pivot support 734 is affixed to the main frame.

As the pedal 730 is pushed downward, the bar 728 rotates about the pivot 732. This forces the bar slot 726 upward, which in turn drives the wheel rod 736 along the slot towards the bar 728 end. The lateral motion ofthe wheel rod 736 along the bar slot 726 rotationally drives the lockout wheel 738 in a clockwise direction.

The lockout wheel 738 is connected to a lockout cam 740 by an axle 742. The lockout cam 740 is attached to a cam support 744, which is in turn affixed to the main frame 14 or otherwise stably supported. The lockout cam 740 is configured to rotate about a cam pivot 746. The lockout wheel 738 may be attached to a wheel support 748, which is also generally attached to the main frame 14. Neither the wheel support 748 nor the cam support 746 prevent rotation of either the lockout wheel 738 or lockout cam 740 to a degree sufficient to lock out treadle 12 motion, as described further below.

As the lockout wheel 738 rotates, it turns the axle 742, which in turn rotates the lockout cam 740 cloclcwise. The axle 742 may extend through the lockout cam 740 to form the cam pivot 746, may attach to the opposite side ofthe lockout cam at the cam pivot point, or may attach to the lockout cam at another point along its surface, hi any case, the cam support 744 is configured to permit the axle 742 to freely rotate the cam 740 to a degree sufficient to lock out freadle 12 motion without impacting the support structure 14.

As the lockout cam 740 rotates, a cam edge may contact a freadle 12 surface. As the cam fully extends, the cam edge may support the freadle, preventing further angular motion or rotation by the treadle. Alternately, the cam edge may mate with a channel on the freadle 12, in the stop blocks 160, or otherwise affixed to the stop brackets 126, 132. Further, in some embodiments the cam 740 edge may include a flange or projection ("cam flange") extending outwardly from the edge in the direction of rotation. The cam flange may also mate with a channel in the manner described above with respect to Fig. 72B.

In an alternate embodiment, the lockout wheel 738, wheel support 748, and axle 742 may be omitted. In such an embodiment the wheel rod 736 attaches directly to and drives the lockout cam, with similar lockout results.

Fig. 74 shows another locking mechanism embodiment 750. In this embodiment, a user may move a slider handle 752 in a back-and-forth manner. The slider handle 752 is affixed to a slider bar 754, which passes through a slider support 756 and terminates in a slider key 758. As the slider handle 752 is pushed, the slider bar 754 moves through the slider support 756, driving the slider key 758 in the same direction the slider handle is moved. As the slider key 758 extends, it may mate with a channel or groove formed in the freadle 12 bottom (not shown), in the stop blocks 160, or otherwise affixed to the stop brackets 126, 130. This mating locks out one or both freadles 12, preventing further treadle movement. Moving the slider handle 752 in the opposite direction withdraws the key 758, allowing free freadle 12 motion. In some embodiments, one slider 750 per freadle 12 may be employed to permit discrete lockout of freadle motion.

The embodiments 724, 750 described with respect to Figs. 73 and 74 may lock out one or both freadles 12. Further, these embodiments 724, 750 may incoφorate any and all ofthe features discussed with respect to Fig. 72B, such as noise-producing and/or tactile feedback mechanisms.

The various embodiments 702, 724, 750 discussed herein with respect to Figs. 72A-74 have been discussed with reference to manual operation thereof, generally by manipulating a pedal 704, 730 or slider 752. Alternate embodiments may actuate any and all ofthe locking mechanisms disclosed herein by electromechanical or other automated means, such as through a servomotor. Figs. 75-78: Dual Reciprocating Treadmill With Arm Exercise

The present exercise apparatus may also include an attachment structure linking the handles to the freadles and/or uprights. For example, Fig. 75 displays the upper body structure 760 of a dual deck treadmill exercise device 780 and a pair of freadles 782. Generally, in the embodiment 780 shown in Fig. 75, the upper body portion 760 ofthe exercise device includes a left and right upright 784, 786, a left and right handle bar 788, 790, and a left and right interconnect 792, 794. Each handle bar 788, 790 is typically affixed to an upright 784, 786, which in turn attaches to a freadle 782, main frame 14 (not shown), or other portion ofthe exercise device 780. ha alternate embodiments, the upright and handle bar may be of single-piece construction.

An interconnect 792, 794 generally operationally attaches the handle bar 788, 790 to the deck 12 or upright 784, 786. Exemplary interconnects suitable for use with the embodiment of Fig. 75 include shocks, torsional springs, elastic members, rigid bars, and so forth. The terms "deck" and "freadmill assembly" 12 are used interchangeably herein. It should be noted that the embodiment 780 shown in Fig. 75 displays two different manners of operationally attaching a handle bar 784, 786 to a deck 12 by means of an interconnect 792, 794, one for each handle bar and deck assembly. Generally, an exercise device 10 will employ the same interconnect structure for both handle bars. Accordingly, the difference between the interconnect structures shown in Fig. 75 is simply a means for displaying two alternate embodiments. Fig. 75 should not be construed as requiring different interconnect mechanisms within a single exercise device, although this may occur in some embodiments. Generally, however, most embodiments employ a single interconnect mechanism.

Returning to Fig. 75 and with respect to the rightmost upper body 760 and treadle assembly 782, the interconnect 794 directly attaches the handle bar 790 to a portion of the assembly 12. The interconnect 794 may, for example, attach to the outer treadle frame. In this embodiment, the interconnect 794 may take the form of a piston cylinder or a solid bar (a solid bar being shown in the figure). When the interconnect 794 is a piston, the bottom portion ofthe interconnect is generally fixably attached to the freadle assembly. Thus, as the handle bar 790 moves up and down, the piston rod extends from and refracts into the piston body in order to maintain a linkage between the handle bar and the freadle 12. This also provides additional resistance against the motion ofthe handle bar 790 and/or freadle 782, thus providing a more strenuous workout for a user ofthe exercise device.

Alternately, the interconnect 794 may be a fixed-length member as shown. In this case, one end ofthe interconnect 794 is generally mated with a slot or recess 796 on either the freadle assembly 12 or the handle bar 790 in order to permit handle bar motion in the event the freadle is locked in place. The slot 796 into which the interconnect 794 (or a lateral member affixed to the interconnect) fits generally runs longitudinally along either the handle bar 790 or the treadle assembly 782. In this manner, when one of either the handle bar and freadle is fixed in place, the interconnect may move angularly to permit the other element to freely experience its full range of motion.

In yet another embodiment, vertical motion ofthe handle bar 790 and freadle 12 may be linked by the interconnect 794. In such an embodiment, the slot 796 may be omitted and the interconnect 794 may still comprise a solid member. Here, the interconnect 794 attachments to one or both ofthe handle bar 790 and treadle 782 may be hinged. Because the interconnect 794 length is fixed and the interconnect does not move laterally of its own accord, up and down motion by either the handle bar 790 or the freadle 782 drives the other in the same manner. For example, when the handle bar 790 is moved up, the treadle 782 is also moved up. Similarly, when the handle bar is moved down, the freadle is pushed down by the downward force exerted through the interconnect and onto the freadle. In this manner, the handle bar 790 motion may be used to drive the vertical motion of a freadle 782 or vice versa.

In a further embodiment, the handle bar 790 may move laterally instead of vertically. In such an embodiment, the interconnect 794 may drive the lateral motion ofthe treadle belt off the handle bar motion, or vice versa. This embodiment is described in more detail below.

In any ofthe aforementioned embodiments, the handle bar 790 may be jointed at some point between the interconnect attachment point 798 and the portion ofthe upright 786 affixed to the freadle 12 or other portion ofthe exercise device 10. The joint 800 may take, for example, the form of a spring hinge (shown in Fig. 75).

Turning now to the left upper body and freadle deck assembly shown in Fig. 75, it may be seen that the interconnect 792 generally extends between and is attached to the left handle bar 780 and left upright 784. Ifthe interconnect 792 is a piston, as shown, then generally the point of attachment between the upright 784 and handle bar 788 is hinged to permit the piston to extend and contract. The hinge 802 may be located at any point along the length of either the handle bar 788 or upright 784, so long as the hinge is located between the two piston ends. Alternately, when the interconnect 792 takes the form of a fixed-length member, the connection between the handle bar 788 and upright 784 is generally fixed. hi either of the embodiments shown in Fig. 75, the motion ofthe handle bars 788, 790 may be used to drive the freadle belts 18. Either the interconnect 792, 794 or the upright 784, 786 may be attached to a roller 804 beneath the freadle belt 18. When the handle bar and upright are of single- piece construction, the handle bar may connect directly to the roller 804. Generally, the connection between the roller and handle bar or upright may be considered another interconnect, insofar as the connection ultimately attaches the deck and handle bar to one another.

As the handle bar 788, 790 moves it in turn moves either the upright 784, 786 or interconnect 792, 794 (depending on which is connected to the roller 804) back and forth through an angle. The interconnect 792, 794 or upright 784, 786 may be attached to the roller 804 either by a one-way bearing or a ratchet and pawl assembly, i either case, as the driving element is moved backward (that is, toward the treadle 12 rear), it rotates the roller 804 and thus the overlying belt 18. As the driving element moves forward with the motion ofthe handle bar 788, 790, the bearing free wheels or the pawl slips along the ratchet (i.e., the element operably connecting interconnect and roller disengages). This disengages the driving element from the roller 804, thus ensuring that the freadle belt 18 is not moved against the natural direction of motion of a user's foot.

Fig. 76 displays another embodiment 800 of an exercise device incoφorating dual deck treadles 808. In this embodiment, the vertical motion ofthe treadles may be driven by the reciprocating pivoting motion ofthe handle bars 810. The handle bars 810, at one end, attach pivotally to the frame 14 at a midpoint ofthe frame's length. A protrusion 812 extends inwardly from each handle bar 810. This protrusion 812 is shown in Fig. 76 in the middle ofthe handle bar joint 814, although the protrusion may not be externally visible in some embodiments. The protrusion 812 seats inside a slot 816 along the side ofthe freadle assembly 808. As the handle bar 810 is pushed forward, the protrusion 812 slides along the freadle slot 816, which in turn forces the freadle 808 front up. Similarly, as the handle bar 810 is moved towards the back ofthe freadle 808, the combination of protrusion 812 and slot 816 drives the freadle front to pivot downwardly. Generally, each freadle 808 is affixed at and rotates about an axle 818 running through the rear ofthe freadles. Accordingly, the "up" and "down" motions herein described are also rotational or angular in nature about the rear of the freadle 808. Additionally, both handle bars 810 are typically rotationally affixed to a point 820 on the exercise device 806 (or points lying along a parallel line peφendicular to the long axis ofthe exercise device) as far forward as the front end ofthe freadle slot 816 or slightly further (as shown in Fig. 76), when the freadle 808 is in a fully down position. The handle bars 810 typically rotate around this point 820, and accordingly may be attached by any means permitting such rotational motion. Although the freadle slot 816 is shown in Fig. 76 as extending along approximately the first half of the freadle 808, it may be positioned at any point along the freadle. The longer the freadle slot 816, the greater the angular motion ofthe treadle 808. Similarly, the closer to the freadle rear the slot is located, the higher the angle achieved by the freadle around the axle.

In some embodiments, the treadles 808 may be attached to one another with an interlink 822 (shown in phantom in Fig. 76). Generally, the interlink 822 is a mechanical linkage capable of transferring motive power from one freadle 808 to another. The rocker interconnect assembly may be substituted for the interlink, in some embodiments, either the interlink 808 or the aforementioned common axle 808 is used, but many embodiments may employ both. As one freadle 808 moves in a given direction (up or down), the interlink 822 drives the second freadle in the opposite direction. The interlink 822 may, for example, take the form of a pivotable Z- or C-shaped member (a Z-shaped interlink is shown in Fig. 76) with the left and right members 824, 826 each attached to a slot, chamber recess, or hinged element of an opposing freadle 808. Generally, the left and right members 824, 826 are attached to the inside sidewall or bottom frame ofthe treadle in such a manner as to avoid interfering with the motion ofthe freadle or associated belt 18. To continue the example, as one treadle 808 is pushed down, the left member 824 may slide along the recess defined in the left freadle 808 or rotate about the hinged element ofthe interlink, moving in a generally downward direction with the freadle. This motion pivots the interlink 822 about its pivot point, which in turn pushes the right member 826 in a generally upward direction along the right treadle's recess, thus exerting an upward force on the second freadle and causing it to rise.

In the event that the handle bars 810 and/or uprights (if used and discrete from the handle bars) are attached to the freadles 808 with a protrusion 812 and slot 816 mechanism, as shown in Fig. 76, the interlink 822 may also drive the handle members 810 back and forth. Even without an interlink 822, the handles may be driven by freadle 808 motion where, for example, the rising and falling of each treadle is controlled either by a servomotor or resistive element, such as a torsional spring or piston (not shown).

The exercise device may use resistive elements to enhance a workout. For example, Fig. 77 displays an embodiment of an exercise device 828 incoφorating resistive elements 830 in a handle bar structure 832. Generally, the exercise device 828 includes two freadles 834 and two handle bars. As with previous embodiments, the front ofthe treadles 834 are capable of an up and down reciprocating motion, while the back of each freadle generally neither rises nor falls. The freadle backs are affixed to a main frame 14 or other portion ofthe exercise device 828 in such a manner as to allow the freadles 834 to rotate around rear ends ofthe freadle as the front ofthe freadles raise and lower.

Each handle bar 832 typically is anchored to a front body structure 836 by an upright 838, or may alternately be attached directly to the front body structure. The handle bar 832 is pivotally or slidably coupled to the upright 838. In the present embodiment, the connection takes the form of a hinge or pivot 840. Each handle bar is also affixed to a piston br other resistive element 830, which in turn is attached to the front body structure 836. Although a piston 830 is shown in Fig. 77, a spring member may be substituted. The portion ofthe handle bar 832 behind the pivot point is referred to as the "handle rear" 842, while the portion in front ofthe pivot point is the "handle front" 844.

Generally, the piston 830 resists the motion ofthe handle bar 832, exerting force on the front 844 ofthe handle bar in the same direction as that placed on the handle rear 842. Since the handle front and rear pivot about the hinge 840, the piston 830 increases the difficulty of moving the handle 832. This, in turn, may provide a user ofthe exercise device 828 with an enhanced upper body workout experience. In alternate embodiments, the front body structure 836 may be omitted and the pistons 830 may attach to other portions ofthe workout device.

Additionally, and with reference to both Fig. 77 and 78, the piston rod 848 may extend through the piston body 850 and into the front body structure or frame 14, ultimately affixing to a portion ofthe treadle assembly 834, such as a front roller 852. In such an embodiment, the piston 830 may pull or push the treadle 834 in the same direction of motion as the handle front 844 (or handle 832 in Fig. 78). The weight ofthe freadle 834 (and any user standing on it) may provide additional resistance to the handle bar 832 motion, further increasing the force necessary to move the handle bar. ha this embodiment, the interior side walls ofthe front body structure 836 or frame 14 each include a slot (not shown). The slot may be curved or straight. The piston rod 843 attaches to the freadle 834 through the slot; the slot further allows the freadle to move in an up-and-down manner while remaining attached to the rod.

In some embodiments 846, the piston 830 may be placed between the handle bar 832 and front body structure 836, with the aforementioned upright 838 omitted, hi such embodiments, the hinge 840 is the connection point between handle bar 832 and body structure 14. This is shown to better effect in Fig. 78.

This embodiment 846 affixes each handle bar 832 to the freadle structure 834 (or main frame 14) by a hinged joint 840. A resistive element 830, such as a piston dampener, is typically attached at one end to the handle bar 832 at some point along the length ofthe handle bar above the hinged joint 840, and is attached at the other end to a portion ofthe main frame 14. Generally, the hinged joint 840 acts as a fulcrum about which a handle bar 832 may revolve. The piston 830 attaches to the handle bar 832 at some point between the hinged joint 840 and handle bar end. The main frame 14 or treadle assembly 834 serves as an anchoring structure for the piston, securing the piston 830 and distributing the resistive force generated by the piston across a sufficiently large stationary mass to prevent unwanted motion ofthe exercise machine 846. As with the embodiment shown in Fig. 77, the piston generally resists motion ofthe handle bar. Here, however, the resisted motion is primarily lateral and angular, rather than the primarily vertical motion produced by the embodiment shown in Fig. 77. Figs. 79A-81: Rear Pivot Height Adjustment

Figs. 79-79 display various views of one embodiment of an adjustment mechanism 854 configurable to adjust a rear pivot height of a freadle 12. Generally, the embodiment 854 may be used with any ofthe treadles described herein. The following discussion ofthe adjustment mechanism 854 makes reference to, and assumes that, a single adjustment mechanism is employed to adjust the height of each treadle 12. It should be noted that one adjustment mechanism 854 may be configured to adjust the height of multiple freadles 12 in alternate embodiments.

Turning now to Fig. 79, a side view of a pair of treadles 12 operably connected to the present embodiment of an adjustment mechanism 854 may be seen. A portion ofthe mechanism affixes to a freadle base, the main frame 14, or another stable portion ofthe exercise device (a "support element"). In this context, "stable" refers to a portion or element ofthe exercise device 10 that does not move with the movement of one or both freadles. Typically, the embodiment 854 includes opposing side brackets 856, each of which are affixed to the support element. A slot 858 is formed in each side bracket, and extends generally vertically from the support element. In alternate embodiments, the slot 858 may extend at an angle from the support element, may be arcuate, may run parallel to the support element (to vary lateral freadle 12 placement), and so forth.

An adjustor pin 862 is at least partially held within one slot 858, operably connects to at least one height adjustment element 860, runs through a rear roller 864, aperture, or space within the treadle (shown in Fig. 79C), and terminates in a second slot. In an alternate embodiment, the adjustor pin 862 may terminate in a series of recesses designed to accept the pin end, or may terminate at a second height adjustment element 860. In yet another embodiment, the height adjustment element 860 may be located on the side ofthe freadle 12 opposite the support bracket 856, and the pin 862 may terminate at the height adjustment element. The height adjustment element 860 may be configured to allow for either continuous or discrete adjustment.

The general operation ofthe embodiment 854 is now described with reference generally to Fig. 79A. The height adjustment element 860 may be manipulated to raise or lower the adjustor pin 862. As the position ofthe adjustor pin is modified, the rear ofthe freadle 12 is raised or lowered accordingly. In the present embodiment 854, such raising and lowering affects only the height ofthe freadle 12 rear. The height ofthe freadle front, as well as the overall freadle throw, remain unchanged. Typically, the top and bottom ofthe slot 858 define the maximum and minimum heights to which the pin 862 may be raised or lowered. (For reference, "throw" is defined the vertical distance traveled by the freadle front between the lowest and highest points ofthe treadle's vertical motion.)

Fig. 79B displays an isomefric view ofthe present adjustment mechanism 854, as viewed from the interior ofthe support bracket 856 (the freadle 12 side). Here, the height adjustment element 860 takes the form of a threaded lead screw, while the operable connection between the adjustor pin 862 and height adjustment element is a threaded adjustor 866 or sleeve. The threaded adjustor 866 is prevented from rotating by the pin 862. Accordingly, as the lead screw is turned 860, the threaded adjustor is drawn up or down the body ofthe screw, depending on the direction in which the screw is turned and the threads run. As the adjustor sleeve 866 moves, the pin 862 and freadle assembly 12 also move.

Fig. 79C displays a back view of a freadle 12 attached to the present embodiment of a height adjustment mechanism 854. As can be seen, the adjustment mechanism 854 shown in Fig. 79B extends along both sides ofthe freadle 12. Alternate embodiments may employ a single threaded adjustor 866 and screw 860 located only on one side ofthe treadle, rather than the double arrangement shown.

As also shown in Fig. 79C, the motor may be encased in a motor case 868. The motor case 868 may also be affixed to one ofthe freadle assembly 12, threaded adjustor 860, or adjustor pin 862 in order to permit the motor case to raise and lower along with the freadle. In this manner, proper tension is maintained in a drive belt (not shown in Fig. 79C) running between the motor and a freadle roller 864, thus permitting mechanized operation ofthe freadle 12 without unduly loosening or tightening the drive belt. Were the drive belt affixed to a support element and unable to move up and down, lowering the freadle 12 might unduly slacken the belt, thus preventing the motor from properly driving the freadle. Similarly, where the freadle 12 is raised in such a scenario, the length ofthe drive belt may prevent the freadle from rising past a certain height.

Fig. 79D displays an apparatus 870 for tensioning a drive belt 874 attached to both a height- adjustable freadle, such as that depicted in Figs. 79A-79C, and non-height-adjustable motor. A tensioner 870 may engage the belt 874. In the present example, the tensioner may consist of a base 876 mounted on a support element, a spring or elastic body 878, and a roller 872 engaging the belt. The spring 878 is configured to pull the roller 872 downward with sufficient force to maintain the proper drive belt 874 tension. As the freadle 12 is raised, the spring 878 is stretched, which exerts additional downward force on the belt 874 through the roller 872. Similarly, as the freadle is 12 lowered the spring contracts, exerting less downward force on the belt through the roller. The spring 878 is typically calibrated to ensure the proper tension is maintained in the drive belt 874 regardless of the freadle height, presuming the freadle height stays within the adjustment range ofthe height adjustment element 869.

In another embodiment (not shown), the tensioner 870 may be replaced by a tension bar. The bar may be attached at one end to the adjustor pin 862 and the motor case 868 at the other. As the pin is raised and lowered, the tension bar may move the motor case back and forth along an arcuate or slanted slot in the support element 856. Because the tension bar is of fixed length, the distance between the motor and freadle roller varies only minimally. This ensures that the drive belt 274 tension is maintained within a proper range.

In yet another embodiment, the tension bar may be omitted, permitting a user to slide the motor case 868 along the arcuate slot as necessary to maintain drive belt tension. In such an embodiment, the motor case 868 may be fixed in place with a clamp, screw, or other similar device to ensure the motor does not slide when activated. Alternate embodiments of the present invention 10 may employ different height adjustment mechanism 854. For ^____^, the lead screw 860 may be replaced by a series of brackets attached to, or angled slots or recesses formed in, the support bracket 856. The adjustor pin 862 may be seated in a bracket, slot, or recess to change the freadle height. In yet another embodiment, the height adjustment element 860 may take the form of a jack capable of raising the pin. In a further embodiment, the adjustor pin 862 may be a biased "pop pin" capable of being pulled away from the surface ofthe height adjustment element, and automatically returning to an engaging position with the adjustment element when the pin is released.

As mentioned elsewhere in this document, the freadles 12 may be locked at an angle to simulate a single treadmill operating either levelly, at an incline, or at a decline ("locked mode"). The freadles may also freely reciprocate ("unlocked mode"). Fig. 80A displays the freadles operating in an unlocked mode, with the freadle rear in a lowest position afforded by the above-referenced adjustment mechanism 854. Colloquially, the lowest position ofthe adjustment mechanism 854 is referred to as "high position" because it affords the greatest incline angle between the freadle rear and the freadle front, when the freadle front is at its maximum operating height (i.e., the greatest range of angular motion by the freadle about the rear freadle axle). Fig. 80B displays the freadles 16 locked in high position.

Just as the treadles 12 may occupy a high position, so may they occupy a low position. Generally, the low position ofthe treadles 12 corresponds to the maximum height to which the rear of the treadles may be raised by the adjustment mechanism 854. This creates a minimum incline angle between the treadle rear and front when the freadle front is at its maximum operating height. Depending on the treadle 12 throw, this may correspond to a decline angle for the freadles, even when the treadle front is at maximum extension. Fig. 81 displays one freadle 12 occupying each ofthe high and low positions discussed above with respect to Figs. 80A and 80B. One freadle 12 is shown in each position. The rearmost treadle is in the high position, while the frontmost freadle occupies the low position. As shown in Fig. 81, the treadles' 12 heights may be independently adjusted in some embodiments to permit each treadle to occupy a different position.

As previously mentioned, the treadle rear heights may be independently adjusted where each freadle 12 is provided with a discrete adjustment mechanism 854. In such a case, the freadles may actually be set for different incline or decline angles, permitting a user to tailor the angle of operation of the freadles as desired. Figs. 82-83F: Treadle Throw Adjustment Mechanism

Fig. 82 displays an embodiment of a treadle throw adjustment mechanism 880. The embodiment may alter the starting and stopping points ofthe throw of one or both freadles 12 (i.e., the angles defining the lowest and highest points ofthe treadle's vertical motion, as measured from the main frame or exercise device base). "Throw" refers generally to the vertical distance traveled by a treadle 12. Additionally, the embodiment may also change the angle through which the treadle fravels during its vertical motion.

The physical structure ofthe throw adjustment 880 will now be described with respect to Figs. 82-83B. A pivot support 882 may be attached to the main frame 14 or another stable portion of the exercise device 10 (a "support element"). In this context, "stable" refers to a portion or element of the exercise device that does not necessarily move with the movement of one or both treadles. A throw bar 884 is rotatably attached to the pivot support 882 about a pivot point 886. The throw bar 884 extends in both directions beyond the pivot point 886, and runs peφendicular to the longitudinal axis ofthe freadles 12. Although only one direction of extension is shown in Fig. 88, both directions of extension are more clearly shown in Fig. 83 A. The throw bar 884 may oscillate through a fixed angle of motion about the pivot point 886. The throw adjustment 880 is operationally attached to the treadle 12 by means ofthe angle adjustment structure, as described in more detail below.

A throw adjust bracket ("throw adjust") 888 surrounds a portion ofthe throw bar. Connected to the throw adjust is an throw handle 890, also referred to as a throw pull. A series of throw recesses 892 are defined at fixed intervals along the longitudinal axis ofthe throw bar 884. An throw pin 894 (the end of which is shown in Fig. 82) passes through at least a portion of an throw recess as well as an egress in the throw adjust, and is fixedly attached at one end to the throw handle. Fig. 83B displays an isometric view ofthe throw adjust 888 and throw pull 890.

The throw handle 890 may be pulled outwardly, away from the throw bar 884 and adjust 888, in order to unseat the throw pin 894 from the throw recess 892. When the throw pin is unseated, the throw adjust may be moved along the longitudinal axis ofthe throw bar. Because the throw pull 890 is affixed to the throw adjust 888, the pull and pin 894 may also move with the throw adjust. In an alternate embodiment, the throw pull 890 maybe removably attached to the throw adjust 888, thus permitting the pull and throw pin 894 to be completely removed from and inserted into the embodiment. When the throw adjust 888 is positioned with its egress over an throw recess 892, the throw pin 894 may be inserted into the recess, thus securing the throw adjust structure to the throw bar 884. In an alternate embodiment, the throw pull 890 and throw pin 894 may be spring biased towards the center of the throw bar 884. Accordingly, the throw pin may be automatically forced into a properly aligned throw recess. Such biasing may also assist in keeping the throw pin 894 in place during operation ofthe mechanism. Colloquially, this structure is referred to as a "pop pin."

Reference is now made to Fig. 83C to describe the various adjustments possible with the present throw adjustment mechanism 880. Generally, the farther away from the pivot point 886 the throw adjust 888 is seated, the greater the vertical distance (translated to angle) traveled by the freadle 12 during operation. This is shown in Fig. 83 C, represented by the angle bars occupying positions "B." The corresponding stroke angle oB, representing the angle between the treadle's minimum and maximum heights, is also shown. By moving the throw adjust 888 closer to the pivot point 886 and seating the throw pin, the vertical distance ("throw") through which the freadle 12 fravels may be minimized. Accordingly, moving the throw adjust 888 and angle bars from positions "B" to positions "A" decreases angle , as shown on Fig. 83C, from angle oB to angle oA. This corresponds to moving the throw adjusts 888 and associated angle bars 896 from position "B" to position "A" on Fig. 83D.

The treadle 12 will still experience some throw, regardless of in which ofthe throw recesses 892 the throw pin 894 sits, unless an embodiment ofthe mechanism permits the throw pin to be seated exactly at the pivot point 886. Because the treadle 12 has a fixed length, the closer the throw adjust 888 sits to the pivot point, the greater the angle ofthe freadle incline, both at the maximum and minimum throw points, presuming the distance between the throw bar 884 and freadle base remains constant. Similarly, the closer the throw adjust 888 sits to the pivot point, the smaller the angle of operation (stroke angle c. on Fig. 83C) experienced by the freadle 12, again presuming the distance between the throw bar 884 and treadle base remains constant. The "angle of operation" refers to the angle traveled by the freadle 12 base as the freadle front travels from its minimum to maximum operational height.

Returning to Fig. 82, in addition to adjusting the throw, the embodiment 880 may also adjust the angle ofthe freadle 12 at both its minimum and maximum vertical extension (the "starting angle" and "stopping angle," respectively). An angle bar 896 is hingedly attached to the throw adjust 888. The hinge attachment ensure that the angle bar 896 remains vertical as the throw bar 884 oscillates. Like the throw bar 884, the angle bar 896 includes a series of angle recesses 898 linearly defined along its longitudinal axis. An angle pin 899 may be seated in an angle recess. The angle pin 899 is fixedly attached to an angle pull 897, and may be unseated from the angle recess 898 by moving the angle pull away from the angle bar 896. Generally, the angle pull 897 is operationally attached to an angle adjust 895. The angle adjust 895 includes an angle egress (not shown) through which the angle pin 899 at least partially passes. When the angle pin is removed from an angle recess, the angle adjust may slide along the angle bar. Placing the angle pin 899 in an angle recess fixes the angle adjust 895 in place.

As with the throw pull 898, the angle pull 897 and angle pin 899 may be fully detachable from the angle adjust 895, or the angle pull may only be moved a fixed distance away from the angle adjust. Further, the angle pull 897 and pin 899 may be spring biased toward the angle bar 896/angle recesses as described above with respect to the throw pin 894, taking the form ofthe aforementioned pop pin.

The angle adjust 895 is attached to the treadle assembly 12 (generally to the freadle base) by a freadle attachment (not shown) located at the top end ofthe angle adjust. The freadle attachment may mate with a receiving cavity or slot running peφendicular to the treadle's 12 longitudinal axis, or in the same direction as the throw bar 884. This structure is referred to herein as a "freadle underslot." As the throw adjust 888 is moved along the throw bar 884, the freadle attachment moves along the treadle underslot in order to keep the angle bar 896 in a relatively vertical orientation. Alternately, the treadle attachment may take the form of a U-joint mated with the fixed rear ofthe treadle 12. The U- joint may maintain the upright orientation ofthe angle bar 896. Similarly, the attachment between the throw adjust 888 and angle bar 896 may also be a U-joint.

Again with reference to Fig. 83C, as the angle adjust 895 is moved along the angle bar 896, the distance between the throw bar 884 and freadle 12 base varies. As this distance changes, the starting and stopping angles also change, although the sfroke angle may not vary. Generally, as the angle adjust 895 approaches the throw bar 884, the starting and stopping angles become more acute (decrease), while the starting and stopping angles become more obtuse (increase) as the angle adjust moves away from the throw bar. Effectively, the starting and stopping angles are each offset from a base plane by angle β, as shown on Fig. 83C. When the angle adjust 895 is in position "C" along the angle bar 896 (see Fig. 83F), the offset angle is equal to angle βC. Ifthe angle adjust 895 is moved to position "D," the offset angle increases to angle βD. Figs. 84A, 84B and 86: Modular Configurations

The exercise device 10 may employ a variety of modular configurations, which may facilitate shipping, packing, storage, and so forth. Figs. 84A and 84B display one embodiment of a modular treadle and frame configuration 1200. Generally, the embodiment includes at least one freadle assembly 1202, main frame assembly 1204, connector 1206, and optionally, a cover 1208 (cover shown to best effect in Fig. 84B). Broadly, the treadle assembly 1202 may be mounted within the main frame assembly 1204 and attached thereto by the connector 1206. The connector 1206 may be designed to be removable in order to allow the disassembly ofthe embodiment 1200, in which case the freadle assembly 1202 is removably mounted to the main frame assembly 1204, or the connector may peπnanently affix the freadle assembly to the main frame assembly. In either event, the general construction ofthe embodiment 1200 from its constituent parts is essentially the same.

With reference to Fig. 84A, the freadle assembly 1202 includes a continuous freadle belt 1208, one roller 1210 located at each end of and inside the treadle belt, and a belt gear 1212 affixed to an axle 1214 extending through the roller at the freadle rear end. The axle 1214 may also be an integral part ofthe roller 1210 rather than simply extending therethrough. In the present embodiment 1202, the free end ofthe axle 1214 is threaded to receive an axle connector 1216 talcing the form of a lug nut or screw cap. In alternate embodiments, the axle connector 1216 may snap- or pressure-fit onto the axle 1214 instead of being screwed thereon, or an adhesive bond between the two may be created.

The axle 1214 is sized to fit within a slot 1218 formed on a slotted receptor 1206. The diameter ofthe axle shaft may be less than the slot 1218 width, or a groove having such a diameter may be formed at a specific point along the axle length. The groove (not shown) may aid in properly aligning the axle 1214 with the slotted receptor 1206, in addition to assisting in securing the axle to the receptor. When the axle 1214 is properly aligned with and resting within the slot 1218, the belt gear 1212 rests on a drive gear 1220 ofthe main frame assembly 1204. The drive gear 1220 is operationally connected to, and is rotated by, a motor 1222. The motor, in turn, is secured to a base 1226 ofthe main frame assembly, typically at one ofthe frame rear corners. In the present embodiment, the motor 1222 is affixed to the base 1226 by several screws, bolts, or other connectors 1224, although other embodiments may adhere the motor to the base or strap it thereto. The main frame assembly 1204 may include a rotating extendable stabilizer element 1228, such as a shock having dampening capabilities (shown in dashed lines on Fig. 84A), hingedly attached along one side of the main frame assembly 1204 and capable of being affixed to a portion of the freadle assembly 1202. Alternately, a slidable, fixed-length stabilizer element may extend peφendicular to the base 1226, and be affixed to both a first stabilizer slot within the side ofthe main frame assembly and a second stabilizer slot within the side ofthe treadle assembly. Such additional stabilizer elements are optional, and are not required in the present embodiment 1200.

Although a single freadle assembly 1202 is shown being mounted to the main frame 1284 in Fig. CH15A, two freadle assemblies may be mounted side by side within a single frame. Generally, the freadle assemblies 1202 are both mounted with the belt gears 1212 facing inwardly. In one embodiment, a slotted receptor 1206 may be affixed to the sidewall ofthe mainframe 1204 at each corner ofthe frame rear, so that each receptor may receive an axle 1214 of a freadle assembly 1202. hi another embodiment, a freadle assembly 1202 may lack an axle 1214 extending beyond the roller body 1210, and the slotted receptor 1206 may be omitted. In this latter embodiment, the axles 1214 of both freadle assemblies 1202 may extend slightly beyond the surface of the belt gear 1212 and be adapted to mate with one another to allow both assemblies to be driven by a single motor 1222. The axles, for example, may be joined by a connector.

Fig. 84B displays the drive gear 1220 and motor assembly 1222 ofthe embodiment shown in Fig. 84A, with two freadle assemblies 1202 mounted thereto. The drive gear 1220 extends sufficiently beyond the end of the drive motor 1222 to engage both belt gears 1212. As the motor 1222 operates, it turns the drive gear 1220, which in turn rotates the belt gears 1212. One or more optional drive belts (not shown) may be looped around the drive gear 1220 and one or both belt gears 1212 at sufficient tension to assist in turning the belt gears. The drive belt may also aid in stabilizing the freadle assemblies 1202, as well as securing the treadles to the main frame 1204. A cover 1208, attached to the treadle assemblies' frames 1230, may extend over and shield the belt gears 1212.

Fig. 85 displays an alternate embodiment 1230 of the drive gear 1220 and motor assembly 1222 discussed with respect to Fig. 84B. In this embodiment, the drive motor 1234 is secured to the frame base 1226 near the middle ofthe rear frame sidewall, instead of in one of the rear corners. Further, the motor 1234 is not affixed to a drive gear, but instead to two drive wheels 1232. Each drive wheel 1232 is slightly larger in diameter than the motor 1234, which ensures that the wheel surface extends above the top ofthe motor. A pair of modified treadle assemblies 1236 lack the belt gear 1212 discussed with respect to Figs. 84 and 85. Instead, the treadle belt 1238 rests directly on the drive wheel 1232, with the freadle roller 1240 being located above the drive wheel. When the motor 1234 is activated, the drive wheel 1232 turns and frictionally spins the freadle belt 1238. The drive wheel may be rotated either clockwise or counter-clockwise, depending on the motion desired for the freadles, and still drive the freadle belt. Since the freadle assemblies 1236 lack belt gears 1212, the cover 1208 shown in Fig. 84B is unnecessary.

Still with respect to Fig. 85, the diameter of each drive wheel 1232 is typically aligned directly with the diameter ofthe roller 1240, in such a fashion that a line connecting the centers ofthe drive wheel and roller would extend generally peφendicularly from the main frame base 1204. This permits the treadles 1236 to pivot up and down at the opposite freadle end without brealdng contact between the freadle belt 1238 and drive wheel 1232, or imparting undesired lateral motion to the freadle from the rotation ofthe drive wheel.

Axles 1242 ofthe freadle assemblies 1236 may still rest in a slot 1218, and may still be connected to a slotted receptor 1206. Further, the axles 1242 of each freadle assembly 1236 may extend inwardly towards the middle ofthe main frame assembly 1204 and slightly beyond the exterior surface of each roller 1240. The axles may be mated together in a manner previously described, or may be mated through a gooseneck extension (not shown, although a connector 1244 is depicted in Fig. 85) affixed to a portion ofthe frame assembly 1204 and curving up and over the motor. The gooseneck extension, or other connection 1244 between the axles 1242, not only stabilizes the freadle assemblies 1236 within the frame 1204, but also assists in regulating the motion ofthe treadles with respect to one another. Fig. 85: Dual Deck Exercise With Handle Motion Tied To Treadle Motion

In some embodiments ofthe exercise device, the handles may actuate the freadles in lieu of, or in conjunction with, a drive motor. Fig. 85 displays an exemplary embodiment 1246 of a dual-deck exercise device with the aforementioned handle 1248 actuation. In this embodiment 1246, a treadle belt 1250 motion may be powered or synchronized to a handle bar motion. Generally, each handle bar 1248 is affixed to a portion of an exercise device body 1252, such as a center console or main frame, by a rotational joint 1254. The rotational joint 1254 allows the handle bar 1248 to move freely in an arcuate manner about the joint, through a fixed angle of rotation. Alternate embodiments may permit a user to configure the angle of rotation ofthe handle bars 1248, varying either the total angle of rotation or the starting and stopping points ofthe angle.

Each handle bar 1248 is typically affixed to a rotational drive element 1256. The rotational drive element may make up the rotational joint 1254, or the drive element may be operably connected to the handle bar 1248 by the rotational joint. The rotational drive element 1256 may, for example, take the form of a freewheel bearing or ratchet and pawl arrangement. As the handle 1248 is moved in one direction, the rotational drive element 1256 engages and turns with the motion ofthe handle. As the handle moves in the opposite direction, the rotational drive element disengages, ceasing any movement powered by or linked to the handle motion. The drive element 1256 may still be subject to residual motion from its own inertia, or the inertia of a different element ofthe device.

The rotational drive element 1256 is also operably coupled to a freadle roller 1258. As the rotational drive element 1256 moves, it turns the freadle roller 1258 in the same direction of motion. A belt 1260 extends across the exterior roller surface. As the roller 1258 turns, it drives the belt 1260 , imparting lateral motion to the top belt surface. Accordingly, motive force may be fransferred from a handle bar 1248 , through the rotational joint 1254, to a rotational drive element 1256, to a roller 1258, and finally to a treadle belt 1260. In the present embodiment 1246, the direction of powered motion ofthe freadle belt 1260 corresponds to the direction of motion ofthe handle bar 1248 in which the rotational drive element 1256 is engaged. That is, ifthe rotational drive element is configured to engage when the handle bar moves back and disengage when the handle bar moves forward, then the freadle belt moves backward when the handle bar moves backward. Continuing the example, when the handle bar 1248 is moved forward, the rotational drive element 1256 disengages and no motive power is provided to the freadle belt 1260.

As shown in Fig. 85, the present embodiment 1246 ofthe exercise device includes two freadles 1250 and two handle bars 1248, and accordingly two rotational drive elements. Each rotational drive element 1258 is operably connected to one handle bar 1248 in the present embodiment, and ultimately drives only one freadle belt 1260. Alternate embodiments may employ a single drive element for both belts.

Further, the motion of a first handle bar 1248 generally opposes that of a second handle bar in the embodiment of Fig. 85. That is, while the first handle bar 1248 moves back, the second handle bar typically moves forward. This simulates the arm-swinging motion making up part of a person's standard stride. Although the handle bars may move in opposite directions at any given moment, the freadle belts generally move or rotate in the same direction. Thus, both the first and second rotational drive elements may impart motive force to the freadles from the same handle motion (i.e., forward or backward), which ensures that only one treadle is motively powered by a handle at any given moment. Alternately, while the first rotational drive element moves the freadle in the same direction as the handle bar, the second rotational drive element may move the freadle in the direction opposite the handle bar.

Fig. 85 shows the handle bars attaching to a front portion ofthe exercise device, with the front roller of each treadle fixed in place and the rear roller of each freadle rising and falling. In an alternate embodiment, the handle bars may be bent or canted in such a manner as to attach to a rear portion ofthe device. In such an embodiment, the rear roller of each freadle generally remains fixed, while the front freadle vertically moves.

In yet another embodiment, the drive element may turn a solid axle extending through both freadle belts, rather than a single roller devoted to each freadle belt. In yet another embodiment, the rotational drive element may be replaced by a vertical drive element. The vertical drive element may convert the arcuate lateral motion of a handle bar to arcuate vertical motion for the freadle, thus driving the up-and-down motion of one freadle, instead of driving the freadle belt motion.

In yet another embodiment, the drive element may turn a solid axle extending through both freadle belts, rather than a single roller devoted to each treadle belt, hi yet another embodiment, the rotational drive element may be replaced by a vertical drive element. The vertical drive element may convert the arcuate lateral motion of a handle bar to arcuate vertical motion for the freadle, thus driving the up-and-down motion of one freadle, instead of driving the freadle belt motion. Figs. 87-90: Interfaces Between Treadles

For a discussion ofthe low friction interface between the freadles 12, reference is now made to Fig. 87, which is an isomefric view ofthe freadle and base frame portion 300 ofthe exercise machine 10 in accordance with an embodiment ofthe present mvention. As indicated in Fig. 87, a low friction surface is provided on the top surface 902 or portion ofthe interior edge or interface of each treadle 12. This is done so that during use ofthe exercise machine in any mode, if a portion of the user's foot steps downwardly on the low friction interface 902 between the freadles 12, the user's foot can track the movement ofthe belts 18 by moving rearwardly on the low friction interface 902.

As shown in Fig. 87, the interior edge 904 or interface of the left treadle 12A is adjacent to the interior edge 906 or interface of the right freadle 12B. Thus, in one embodiment, both interior edges 904, 906 have low friction surfaces 902 and, as a result, are low friction interfaces 902. hi another embodiment, only one ofthe interior edges 904, 906 is a low friction surface 902. In one embodiment, each low friction surface 902 extends generally the entire length ofthe freadle 12. hi another embodiment, each low friction surface only extends over a portion ofthe entire length ofthe freadle 12.

For puφoses of this discussion, "low friction surface" is defined as being any type of surface where a foot or shoe of a person using the exercise machine may easily, slidably or rollably displace along the surface with minimal frictional adhesion between the surface and the foot or shoe. For example, as shown in Fig. 88, which is an enlarged isometric view ofthe low friction interface 902 illusfrated in Fig. 87, in one embodiment, a "low friction surface" includes a slick, slidable surface, hi one embodiment, the slidable surface is formed of TEFLON ™, nylon, or another polymer having a low coefficient of friction. In one embodiment, the slidable surface is a material having a low coefficient of friction that is further lowered by the application of a lubricant (e.g., a light oil, wax, silicone, etc.).

In another embodiment, as shown Fig. 89, which is an enlarged isomefric view ofthe low friction interface illusfrated in Fig. 87, a "low friction surface" 902 includes a set of rollers 908. In one embodiment, the rollers 908 are cylindrically shaped with longitudinal axes peφendicular to the fravel direction ofthe freadle belt 18. In another embodiment, the rollers 908 are spherically shaped. In one embodiment, the "low friction surface" 902 includes a combination of rollers and slick, slidable surfaces. In one embodiment, one low friction interface may have rollers and the other low friction interface may have a slick, slidable surface.

By using a "low friction surface" 902 at the interfaces ofthe freadles 12, the user's foot or shoe is more easily able to move with the belts 18 during freadmill operation. This reduces the chances that the user will stumble and/or fall.

Besides providing the low friction surface 902 at the interior edges 904, 906 or interfaces of the right and left freadles 12, the low friction surface may additionally be provided in other locations. For instance, in one embodiment, the exterior edges and surfaces of the freadles 12 are provided with a low friction surface. Also, in one embodiment, as shown in Fig. 90, which is an isomefric view of the freadle and base frame portion 300 ofthe exercise machine, the machine may be equipped with a third or middle freadle 910. As illusfrated in Fig. 90, the third or middle treadle 910 is located between the left and right freadles 12. The left and right freadles 12 are equipped with a displaceable belt 18 or fread and the third or middle freadle 910 is provided with a "low friction surface" as defined above. Thus, in one embodiment, the low friction surface ofthe middle freadle 910 includes a set of rollers. In another embodiment, the low friction surface ofthe freadle includes a slick, slidable surface, which may or may not be lubricated. Alternatively, in one embodiment, the middle treadle's low friction surface is a displaceable treadle belt similarly configured to the displaceable freadle belts described elsewhere in this specification.

As indicated in Fig. 90, if a portion of a user's foot 912 accidentally steps on the middle stationary freadle 910 during use, the user's foot 912 can move along with the belt 18 ofthe adjacent freadle 12. Thus, the middle treadle 910 with its low friction surface reduces the potential for tripping or falling. hi one embodiment, as shown in Fig. 90, a biasing mechanism 428, such as a coil spring 428 or set of coil springs, upwardly biases each freadle 12 and, as a user steps on a particular freadle, the freadle 12 moves downward, hi one embodiment, a coil spring 428 engages a flange 430 protruding outwardly from the frame 52 ofthe freadle 12 in order to support the freadle and couple the freadle with the base frame 14 ofthe exercise machine. In other embodiments, the freadles 12, including the middle freadle 910, are biased in the upward position by other biasing mechanisms or means as described elsewhere in this specification. In one embodiment, a biasing mechanism 428 (e.g., a spring structure, etc.) attached to the middle freadle 910 causes the middle treadle 910 to remain in the upward position unless stepped on by the user. Once released, the biasing element 428 causes the middle freadle 910 to return to the upward position.

In one embodiment, the middle freadle 910 can pivot to be flush with the highest portion of an upwardly moving freadle 12. For example, the middle freadle 910 fracks the highest treadle 12, which at this point in the example is the right freadle 12B, downwardly to a midway position where the left and right freadles 12 are generally even in height. At that point, unless the middle freadle 910 is being stepped on, the middle freadle 910 fracks the left freadle 12B upward to its peak height. As the left freadle 12A begins its descent, the middle freadle 910 fracks the left treadle 12A to the midway position, where the middle freadle 910 again begins to track the right freadle 12B upward, unless the middle freadle 910 is being stepped on. Thus, if a user steps partially on the highest treadle 12 and partially on the middle treadle 910, the middle freadle 910 is at the proper height. Fig. 91: Dual Treadle with Rollers Providing a Striding Surface

For a discussion of an embodiment ofthe exercise machine having an alternative fread surface, reference is now made to Fig. 91, which is an isomefric view ofthe treadle and base frame portions 300 of the exercise machine 10. As shown in Fig. 91, each fread surface 914 (i.e., the displaceable upper surface of a freadle 12 intended to be freaded on by a user's feet or shoes) includes a plurality of adjacent, coplanar rollers 916. Thus, in this embodiment, the plurality of rollers 916 has been substituted for the displaceable belt 18 utilized as the fread surface 914 in some of the other embodiments described in this specification.

As shown in Fig. 91, the left and right freadles 12 A, 12B are pivotally attached to the base frame 14 through two or more link members 918 that may be welded or integral to the base frame 14 and extend upwardly therefrom. In one embodiment, a pivot shaft 330 or member extends through a freadle frame 52, thereby permitting the freadle frame 52 to pivot about the shaft 330. hi one embodiment, the treadles 12 share the same pivot shaft 330. In another embodiment, each freadle 12 pivots about its own pivot shaft 330 and, the pivot shafts 330 are axially aligned along the same axis. Thus, in one embodiment, regardless of whether the each freadle 12 has its own pivot shaft 330 or whether the treadles 12 share a pivot shaft 330, the treadles 12 are pivotably displaceable about a single rotational axis.

As indicated in Fig. 91, in one embodiment, a plurality of rollers 916 are positioned within the treadle frame 52 in a co-planar or substantially co-planner (such as with a concave or convex plane) arrangement. In one embodiment, the rollers 916 are supported in the freadle frame 52 by a plurality of rods about which the rollers can rotate during operation, hi one embodiment, the rollers 916 may be freewheeling. In another embodiment, the rollers 916 are interconnected through the use of a drive belt, chain, or gearing mechanism, such that the rotation ofthe rollers can be controlled to provide a selectable amount of resistance to rotation. For instance, a drive mechanism or motor 88 may be provided about the rear portion of the freadle 12. The drive mechanism may have a confrol, such as an electrical confrol, located on the center console or handlebar ofthe exercise machine so that the user can easily regulate the amount of resistance or the rotational speed ofthe rollers 916. The freadles 12 can be used with springs or dampeners if desired to condition the motion ofthe freadles 12. Figs. 92-105: Treadle Frames with Pivot Location Between Ends of Treadle

For a discussion ofthe various manners of coupling the freadle frames 52 to the base frame 14, reference is now made in turn to Figs. 92. Fig. 92 is an isometric view ofthe freadle and base frame portion 300 ofthe exercise machine 10. As shown in Fig. 92, in one embodiment the base frame 14 is coupled with the treadle frame 52 at a point or location between the longitudinal ends of each freadle 12. Specifically, a frame member 918 extends upwardly from the base frame 14 and the freadle frame 52 is pivotally attached to the frame member 918 at a point between the longitudinal ends ofthe freadle 12. As indicated in Fig. 92, freadles 12 can be pivoted at locations other than the rear end of a freadle or other than at a treadle's rear roller 30.

As illusfrated in Fig. 92, in one embodiment, an elongated pivot rod 330 extends from a first frame member 918 to a second frame member 918 through both the left and right treadle frames 52 so as to pivotally support the left and right treadles 12A, 12B at a pivot point located between the ends of the freadle. In other words, the left and right freadles 12A, 12B share the same pivot rod 330 and are rotationally displaceable about the same rotational axis.

In another embodiment, each treadle 12 has its own pivot rod 330 about which the freadle is rotationally displaceable. Each pivot rod 330 is supported by frame members 918 . The pivotrods 330 are axially aligned and, as a result, the left and right freadles 12 A, 12B pivot about the same . rotational axis.

The frame members 918 are sized so as to provide a vertical offset between the freadles 12 and the base frame 14. This allows the freadles 12 to be pivoted to various desired positions or orientations during use. Figs. 93-94

For a discussion of another manner of coupling the freadle frames 52 to the base frame 14, reference is now made to Figs. 93 and 94, which are, respectively, an isomefric view and a right side elevation ofthe freadle and base frame portion 300 ofthe exercise machine. As shown in Figs. 93 and 04, in one embodiment, friangular frame members 52 are provided to pivotally couple the treadles 12 to the base frame 14 ofthe exercise machine. In one embodiment, each freadle 12 is coupled to the base frame 14 by a single triangular frame member 52. In another embodiment, each freadle 12 is coupled to the base frame 52 by a pair or set of triangular frame members 56.

As indicated in Figs. 93 and 94, the pivot points 330 between the base frames 14 and the friangular members 52 are between the ends ofthe top surface ofthe freadles 12, but offset away from the top surface ofthe freadles. Thus, the ends ofthe top surface ofthe freadles 12 and the pivot point 330 form the three points of a triangle when viewed from the side as shown in Fig. 94.

As shown in Figs. 93 and 94, in one embodiment, a single pivot rod 330 extends through the triangular frame member 52 or members coupled to the right freadle 128, the friangular frame member 52 or members coupled to the left treadle 12A, and the base frame 14 so as to pivotally support the left and right freadles 12A, 12B. In other words, the left and right freadles 12A, 12B share the same pivot rod 330 and are rotationally displaceable about the same rotational axis.

In another embodiment, the triangular frame member 52 or members of each treadle 12 has its own pivot rod 330 about which the freadle is rotationally, displaceably coupled to the base frame 14. However, the pivot rods 330 are axially aligned and, as a result, the left and right freadles 12A, 12B pivot about the same rotational axis.

As shown in Fig. 93, for each freadle 12, the friangular frame member 52 is coupled to the axle ofthe rear roller 30 and if to the axle ofthe front roller 28, its axle. Alternatively, the triangular frame member 52 can be coupled with a portion ofthe freadle frame, thereby pivotally connecting the treadle 12 to the base frame 14. As indicated in Figs. 93 and 94, each freadle 12 pivots off of the pivot point 330, which is offset below the level ofthe front and rear rollers 28, 30 at a location between the rollers 28, 30.

As indicated in Fig. 93, the displaceable fread surface 18 (i.e., fread belt) can be driven by the rear roller 30 or front roller 28 of a treadle. However, as illusfrated in Fig. 94, in one embodiment, the pivot point 330 between the triangular frame members 52 and the base frame 14 may include an offset roller 31 such as an idler roller or a drive roller about which the belt 18 is wound for controlling the speed and direction of belt movement. As shown in Fig. 94, in one embodiment, the three rollers 28, 30, 31 of each freadle 12 are held in location by the respective freadle frame and/or the respective triangular frame member 52. Consequently, the three rollers 28, 30, 31 define a triangle about which the belt 18 passes. Depending on the embodiment, the belt 18 can be driven by the rear, front, or offset roller 30, 28, 31. Figs. 95-96

For a discussion of another manner of coupling the treadle frames 52 to the base frame 14, reference is now made to Figs. 95 and 96. Fig. 95 is an isometric view ofthe freadle and base frame portion 300 ofthe exercise machine, and Fig. 96 is a left side view ofthe treadle 12 illusfrated in Fig. 95. As indicated in Figs. 95 and 96, in one embodiment, the freadles 12 are coupled to the base frame 14 through a pair of pivot points 920, 922 so as to produce an articulated motion ofthe treadle 12 during use.

As shown in Figs. 95 and 96, a flange 918 extends upwardly from the base frame 14 and provides a first pivot point 920 to which one end of a pivot link 924 is connected. The other end of the pivot link 924 is coupled with a roller 30 of a freadle 12 and defines a second pivot point 922. Alternatively, in one embodiment, the pivot link 924 may be coupled with a portion ofthe freadle frame 52 forward ofthe rear ofthe treadle 12 to define the second pivot point 922 and for supporting or connecting the treadle 12 with the base frame 14.

As illusfrated in Fig. 95, a spring 428 is attached between the treadle frame 52 and the base frame 14 ofthe exercise machine. The spring 428 upwardly biases the freadle 12 in an upright position. As shown in Fig. 96, when a freadle 12 is in the fully upright position, the bottom edges of the freadle frame 52 and the top edges ofthe corresponding pivot 924 links form an acute angle". As the freadle 12 is pushed downward, the angle" becomes more acute.

As can be understood from Figs. 95 and 96, in operation, as a user's foot pushes downwardly on a freadle 12, the freadle 12 moves downwardly as it pivots counterclockwise around the second pivot point 922. At the same time, the freadle 12 also moves rearwardly as the link 924 and the freadle 12 pivot clockwise around the first pivot point 920. Thus, as indicated in Fig. JP10, these movements combine to create an articulated motion including a downwardly pivoting motion and a rearwardly pivoting motion, when the user's foot pushes downwardly on a freadle 12. Conversely, when the user's foot moves upwardly off ofthe freadle 12, the spring force moves the treadle 12 upwardly and forwardly due to the dual pivot points 920, 922. Therefore, as can be understood from Fig. 96, when a downward force is applied to a freadle 12, the freadle 12 moves generally downward and reward, and when the downward force is removed, the freadle 12 returns to its initial position by moving generally upward and forward. Figs. 97-99B: Treadle with Two Treadle Frame Arrangements

For a discussion of another manner of coupling the freadle frames 52 to the base frame 14, reference is now made to Figs. 97-99B. Fig. 97 is an isomefric view ofthe freadle and base frame portion 300 ofthe exercise machine, the freadles 12 having a frapezoidal configuration when viewed from the side. Fig. 98A is a right side view ofthe right freadle 12B illustrated in Fig. 97 and indicates the trapezoidal configuration ofthe freadle 12. Fig. 98B is a right side view of an alternative embodiment ofthe embodiment ofthe invention illusfrated in Fig. 97 and indicates the friangular configuration ofthe freadle 12. Fig. 99A is a right side view ofthe freadle 12 illusfrated in Fig. 97 and indicates the trapezoidal freadle 12 displacing about a pivot point 330. Fig. 99B is the same view ofthe freadle illustrated in Fig. 98 A and indicates the friangular freadle 12 displacing about a pivot point 330.

As indicated in Figs. 97-99B, in one embodiment, each freadle 12 has more than two rollers about which the continuous fread belt 18 (i.e., fread surface) changes direction. For example, in one embodiment, as illusfrated in Figs. 97, 98A and 99A, each freadle 12 has an upper freadle frame 52A and a lower treadle frame 52B. Each freadle frame 52A, 52B has a front roller 28 and a rear roller 30 about which the continuous fread belt 18 changes its direction of fravel. Thus, as illustrated in Figs. 98A and 99A, in one embodiment, the freadle frames 52A, 52B and rollers 28, 30 of each freadle 12 are oriented, when viewed from the side, such that each of the four rollers 28, 30 forms a single comer of a frapezoid.

While Figs. 97, 98A, and 99A depict a freadles 12 with four roller equipped comers, those skilled in the art will recognize that freadles 12 with greater or lesser numbers of roller equipped comers may be developed without departing from the spirit of embodiment depicted in Fig. 97. For example, as shown in Figs. 98B and 99B, in one embodiment, the freadles are equipped with a freadle framework 52 and three rollers 28, 30, 31 about which the continuous fread belt 18 changes direction. Thus, as indicated in Figs. 12B and 13B, in one embodiment, the treadles 12 have a triangular configuration when viewed from the side, the triangle having three roller equipped comers. As shown in Figs. 97-98B, a frame 52 supports each ofthe rollers 28, 30, 31, and the frames and rollers are maintained in rigid position relative to each other, thereby allowing each treadle 12 to move as a complete, generally rigid unit. As indicated in Figs. 97-98B, the top frame 52A supports the deck 26 just under the tread belt 18. With respect to the four roller embodiment as illustrated in Figs. 97 and 98A, a bottom frame 52B connects the bottom two rollers 28, 30, and a top frame 52A connects the top two rollers 28, 30. With respect to the three roller embodiments, the top two rollers 28, 30 may be maintained in position relative to the single bottom roller 31 through a variety of framing methods, one of which is illustrated in Fig. 98B.

As illusfrated in Figs. 97, 99A and 99B, in one embodiment, a bottom roller 30, 31 is mounted between a pair of brackets 918 on the base frame 14 so as to allow the treadle 12 (i.e., freadle frames 52 or framework and rollers 28, 30, 31 held in generally rigid position relative to each other) to pivot as a single unitary structure. In other embodiments, the pivot point 330 between the treadle 12 and the base frame 14 is located along the treadle frames 52 or framework away from the rollers (e.g., see pivot arrangement in Fig. 92).

As indicated in Fig. 99A, when the pivot connection 330 between the freadle 12 and the base frame 14 is the rotational axis ofthe bottom left roller 30, the lateral end ofthe freadle opposite the pivot connection 330 pivots up and down around the pivot point 330 during use. Similarly, when the pivot connection 330 between the freadle 12 and the base frame 14 is the rotational axis ofthe bottom right roller 28, the lateral end ofthe treadle opposite the pivot connection 330 pivots up and down around the pivot point 330 during use. Similar pivot action between the treadle 12 and the base frame 14 can be envisioned when the pivot connection is the rotational axis ofthe top left or top right rollers 28, 30.

As indicated in Fig. 99B, when the pivot connection 330 between the treadle 12 and the base frame 14 is the rotational axis of the bottom roller 31 , the top end of the freadle 12 opposite the pivot connection 330 pivots up and down around the pivot point 330 during use. Similarly, when the pivot connection 330 between the freadle 12 and the base frame 14 is the rotational axis ofthe top right roller 28, the left lateral end ofthe treadle pivots up and down around the pivot point 330 during use.

As shown in Fig. 98 A, with respect to the four roller embodiment ofthe invention, to maintain the rollers 28, 30 in a generally rigid relationship to each other, the upper freadle frame 52A can be supported on the bottom freadle frame by a rigid structural member or a stiff dampener and/or spring structure 928. With respect to the three roller embodiment, a rigid structural member 930 or a stiff dampener and/or spring structure may also be employed to maintain the rollers 28, 30, 31 in a generally rigid relationship to each other. Figs. 100-lOlB hi alternative versions ofthe four roller and three roller embodiments depicted in Figs. 97- 99B, the position ofthe rollers 28, 30, 31 may be allowed to shift relative to each other, thereby eliminating the need for a pivot connection 330 between the base frame 14 and the freadles 12. This concept is illusfrated in Figs. 100 and 101A, which are, respectively, an isometric view ofthe freadle and base frame portion 300 ofthe exercise machine and a right side view ofthe treadle illusfrated in Fig. 100.

As shown in Figs. 100 and 101A, the treadles 12 have an upper treadle frame 52A and a lower tread frame 52B. The upper tread frame 52A supports a front roller 28, a rear roller 30 and a deck 26 that supports the fread belt 18 (i.e., fread surface). The lower freadle frame 52B supports a front roller 28 and rear roller 30. As indicated in Figs. 100 and 101A, a continuous fread belt 18 is routed about the freadle 12 and changes direction at each roller 28, 30.

As shown in Figs 100 and 101 A, in one embodiment, the treadle 12 has a frapezoidal configuration when viewed from the side, and the lower rear roller 30 and the front rear roller 28 are fixed relative to the base frame 14. In one embodiment, this is achieved by fixedly attaching the axes of the rollers 28, 30 to the base frame 14. In another embodiment, this is achieved by fixedly attaching the lower treadle frame 52B to the base frame 14.

As shown in Fig. 101 A the frapezoidal freadle 12 is capable of collapsing such that the upper freadle frame 52A, with its front and rear rollers 28, 30, displaces downwards and rearwards while the lower freadle frame 52B, with is front and rear rollers 28, 30, remains positionally fixed relative to the base frame 14. As illusfrated in Fig. 101 A, when the upper freadle frame 52A collapses downward and rearward, the upper freadle frame 52A remains generally parallel to the lower freadle frame 52B. A spring or dampener (similar to the one illusfrated in Fig. 98A), or a set thereof, can be used to maintain the upper freadle frame 52A in the upper most position relative to the lower treadle frame 52B (e.g., as shown Fig. 101A).

As indicated in Fig. 101 A, during use, the upper freadle frame 52A moves downwardly and rearwardly relative to the lower frame 52B when the user exerts downward force on the upper freadle frame, hi an alternative embodiment, the upper freadle frame 52A moves downwardly and forwardly, depending upon the orientation ofthe exercise machine or the user thereon.

As indicated in Fig. 101 A, when the user stops applying downward force to the upper freadle frame 52A, the treadle frame 52A returns to the upper most position by moving upward and forward. This return to the upper most position is brought about by the spring(s) and/or dampener(s) biasing the upper freadle frame 52A upwardly.

As shown in Fig. 101A, B, in one embodiment, the drive roller may be the lower rear roller 30, while in other embodiments, the drive roller may any ofthe other rollers. As with many ofthe various embodiments disclosed herein, the left and right treadles 12 may be interconnected through a rocker arm, attached dampeners, interconnected springs, or other means so that when one ofthe freadles 12 is moved downwardly by the user's foot, the other freadle 12 is mechanically moved upwardly an equal or proportionate distance, and vice versa. Fig. 102: Treadle Frame with Pivot Link Members

For a discussion of another manner of coupling the freadle frames 52 to the base frame 14, reference is now made to Fig. 102, which is an isomefric view ofthe freadle and base frame portion 300 ofthe exercise machine. As indicated in Fig. 102, in one embodiment, the freadles 12 are coupled to the base frame 14 via pivot link members 924.

As illusfrated in Fig. 102, flanges 918 extend upwardly from the base frame 14. A first end of each pivot link member 924 is pivotally secured to the flanges 918 via a support rod 932 to form a first pivot point 920. The rod 932 serves as the axis about which the pivot link 924 may rotate relative to the flange 918. The other end of each pivot link 924 is coupled with a rear roller 30 of a freadle 12 and defines a second pivot point 922. Alternatively, each pivot link 924 may be coupled with a portion ofthe freadle frame 52 forward ofthe rear ofthe freadle 12 to define the second pivot point 922 and for supporting or connecting the freadle 12 with the base frame 14. Alternatively, separate rods 932 may be used for each freadle, and/or the rod(s) may be supported by two, three or four flanges 918.

As shown in Fig. 102, in one embodiment, a torsion spring 934 is wound about the first pivot point 920 with a first end ofthe spring secured to a portion ofthe flange 918 and a second end ofthe spring secured to a portion ofthe link member 924. This arrangement tends to move the link member 924 upwards or counterclockwise relative to the flange about the first pivot point.

As indicated in Fig. 102, when a freadle 12 is in the fully upward position, the upward edges ofthe treadle frame 52 and the upward edges ofthe associated pivot link members 924 form an obtuse angle X. As the treadle 12 is pressed downward, the angle X becomes more obtuse. hi one embodiment, the front end of each freadle 12 is supported by springs or dampeners as described elsewhere in this specification. As the user's foot contacts the treadle 12 and depresses the treadle, the treadle pivots about the second pivot point clockwise and the link pivots 924 about the first pivot point 920 clockwise. In another embodiment, the freadles 12 are interconnected through a rocker arm as described elsewhere in this specification, and as one freadle is depressed, the opposing treadle 12 moves upward and rearward. Fig. 103 - 104: Treadle Frame with Four Bar Linkage

For a discussion of another manner of coupling the freadle frames 52 to the base frame 14, reference is now made to Figs. 103 and 104, which are, respectively, an isomefric view and a left side elevation ofthe treadle and base frame portion 300 ofthe exercise machine. As shown in Figs. 103 and 104, in one embodiment, each freadle 12 is coupled to the base frame 14 of the exercise machine via a four bar linkage 936.

As illusfrated in Figs. 103 and 104, in one embodiment, each four bar linkage 936 includes an upper and lower horizontal linkage member 938, 940 and a front and rear vertical linkage member 942, 944. The linkage members are pivotally attached.

As shown in Figs. 103 and 104, in one embodiment, a spring 428 is connected between the upper and lower horizontal members 938, 940. The spring 428 biases the upper and lower members 938, 940 away from one another and keeps the four bar linkage assembly 936 generally in the shape of a parallelogram, when the spring 428 is uncompressed. As indicated in Figs. 103 and 104, the lower right joint ofthe four-bar linkage is attached to the base frame 14 at a first pivot point 920, and the rear ofthe freadle 12 is attached to the upper left joint ofthe four-bar linkage at a second pivot point 922. In one example, each treadle 12 is coupled with the base frame 14 through a first set of four bar linkages 936 and a second set of four bar linkages 936. In one embodiment, the second pivot point 922 coincides with the rotational axis ofthe rear freadle roller 30. In another embodiment, the second pivot point 922 intersects the freadle frame 52 at a point that is forward of the rear freadle roller 30.

As can be understood from Fig. 104, when the user's foot contacts a freadle 12 and moves it downwardly, the spring 428 compresses and the upper horizontal member 938 moves closer to the lower horizontal member 940 (i.e., the parallelogram begins to collapse) and the front and rear vertical members pivot forwardly about their lower pivotable connections. From the left-side perspective as shown in Fig. 104, as the freadle 12 is depressed, the four bar linkage 936 pivots counterclockwise about the first pivot point 920, and the freadle 12 pivots counterclockwise about the second pivot point 922. Thus, as the freadle 12 is depressed, the four bar linkage 936 fransitions to a collapsed configuration and the freadle transitions from an inclined orientation to a less inclined orientation.

As the user's foot is removed from the freadle surface, the compressed spring expands and separates the upper and lower horizontal members 938, 940 while shifting the upper horizontal member 938, as well as the freadle 12, rearwardly. Thus, as the user's foot is removed from the treadle 12, the four bar linkage 936 fransitions back to its expanded configuration and the freadle 12 fransitions from a generally horizontal orientation to a more inclined orientation. In one embodiment, the treadles 12 are mechanically interconnected so that the left and right treadles move in opposing directions during use. Fig. 105: Swing Arm Supported Treadle with Cable Interconnect

The treadles 12 of the exercise machine ofthe present invention may be interconnected together so the treadles 12 displace relative to each other in an alternating manner. This may be accomplished via a variety of interconnection arrangements. One of these interconnection arrangements is illustrated in Fig. 105, which is an isomefric view ofthe freadle and base frame portion 300 ofthe exercise machine.

As shown in Fig. 105, each freadle 12 is supported by two swing arms 942. A cabling system is used to interconnect the left and right freadles 12 and to effect their movement opposite to one another during use ofthe exercise device.

As illusfrated in Fig. 105, a generally U-shaped frame structure 14 is provided having a rectangular base portion and rectangular side supports extending upwardly from the base portion. Each freadle 12 is pivotally attached to a rectangular side support through a pair of swing arms 942. In one embodiment, each swing arms is attached to a portion of the freadle frame 52. In another embodiment, each swing arm 942 is attached to a treadle 12 at a roller 28, 30. As can be understood from Fig. 105, because ofthe swing arms 942, each freadle 12 moves generally arcuately downwardly when depressed. Also, the slope ofthe freadle surface depends on the relative lengths ofthe attached swing arms 942. In one embodiment, the length of some or all of the swing arms 942 may be adjusted to allow the slope ofthe freadles 12 to be modified by the user.

In one embodiment, each freadle 12 has, as one ofthe rollers 28, 30, a drive roller that moves the tread belt 18 around the rollers ofthe treadle 12. In one embodiment, the drive roller is a roller with an integral motor within the roller. In another embodiment, the drive motor is secured to the freadle frame 52 to displace with the freadle frame. The drive motor then powers the drive roller via a drive belt or gear arrangement, hi yet another embodiment, the drive roller is powered by a motor mounted on the U-shaped frame structure 14. Power is fransferred from the frame-mounted motor to the drive roller via a drive belt routed around sheaves on a tension link.

As shown in Fig. 105, at a first end ofthe frame structure, an upwardly extending center support member 944 is attached to the first swing ami 942' of each freadle 12 through an elastic cable 946. The elastic cable 946 has an elasticity that permits the freadles 12 to swing forwardly and rearwardly relative to the frame structure 14. In one embodiment, the elastic cables 946 are selected to return the treadles 12 to a desired orientation relative to one another when no forces are being applied to the freadles.

At a second end ofthe frame structure, which is opposite the first end ofthe frame structure, the second swing arm 942" ofthe right freadle is attached to one end of a cable 948'. The cable extends from the second swing arm 942" ofthe right freadle, around a first pulley 950 that is attached via a flange to the frame structure 14, and up over the top of a second pulley 952A that is mounted on an axle 954 supported by flanges secured to the side supports ofthe frame structure 14.

In a similar fashion, the second swing arm 942" ofthe left freadle is attached to one end of another cable 948". The cable 948" extends from the second swing arm 942" ofthe left freadle 12, around a first pulley 950 that is attached via a flange to the frame structure 14, and under the bottom of a second pulley 952B that is also mounted on the axle 954.

As can be understood from Fig. 105, because both freadles 12 are connected via cables 948', 948" to pulleys 952A, 952B mounted on the axle 954, and because each cable 948', 948" is wound about its respective second pulley 952A, 952B in a manner opposite from the corresponding cable 948', 948", the axle 954 translates motion from the right freadle to the opposing left freadle in a reversed manner. For instance, in operation, as the user's foot drives the right freadle 12, the right freadle moves rearwardly and downwardly and the right treadle's cable 948' is pulled downwardly. This imparts a cloclcwise motion (as viewed from the right side ofthe frame 14) on the pulley 952 A attached to the axle 954. The axle 954 rotates in a cloclcwise manner, which pulls the left treadle's cable 948" upwardly, thereby moving the left freadle 12 upward and forward. Conversely, when the user's left foot depresses the left freadle, the left freadle moves downwardly and rearwardly, which pulls down on the left treadle's cable 948" and imparts a counterclockwise rotation ofthe axle 954. This pulls the right treadle's cable 948' upwardly thereby moving the right freadle 12 forward and upward.

As indicated in Fig. 105, in one embodiment, a brake mechanism 956 may be attached to either end ofthe axle 954 and may be electronically or mechanically controlled. The brake mechanism 956 may provide selective levels of resistance to axle rotation, thereby providing a selective resistive force to the movement ofthe freadles 12. Fig. 106: Dual Treadle Exercise Machine with Sliding Treadles and Cable System Interconnect

For a discussion of another manner of interconnecting the freadles together so the treadles displace relative to each other in an alternating manner, reference is now made to Fig. JP20, which is an isomefric view ofthe exercise machine 10. As indicated in Fig. JP20, in one embodiment, the exercise machine 10 has a pulley and cable system that provides for opposing motion ofthe left and right freadles 12 relative to one another.

As shown in Fig. 106, in one embodiment, the exercise machine 10 includes a lower frame portion 14' that is generally U-shaped, a U-shaped upper frame portion 14" with downwardly extending arms 960 connected to the lower frame portion 14', and left and right rectangular posts 958', 958" extending between a pair of rectangular post-receiving openings in the lower frame portion 14' and the upper frame portion 14". A center post 40 extends upwardly from the upper frame portion 14" and a console and handlebars 44 may be attached at the free end ofthe center post 40.

As illusfrated in Fig. 106, in one embodiment, each freadle 12 is connected to its respective rectangular post 958', 958" through a sleeve 962', 962" and U-shaped coupling member 964', 964" slidably engaged about the respective post 958', 958". In one embodiment, the U-shaped coupling member 964', 964" is pivotally attached to a portion ofthe freadle frame 52 at a pivot point 330 so that the freadles 12 can pivot about the pivot point 330 as the freadles 12 move upwardly and downwardly as guided by the rectangular posts 958', 958". In one embodiment, each pivot point 330 coincides with the pivotal axis of a freadle roller. In another embodiment, each pivot point 330 is attached to a point on the freadle frame other than at an axis of a freadle roller. In one embodiment, the interconnection between the coupling member 964', 964" and the freadle 12 can be rigid and non- pivotal.

As illusfrated in Fig. 106, a cable 948 is attached to a first attachment point 966" on the right sleeve 962" and to a second attachment point 966' on the left sleeve 962'. The cable 948 is wound about a set of four pulleys 968 pivotally secured to the upper and lower frame portions 14', 14" ofthe exercise machine 10.

As can be understood from Fig. 106, in operation, as the user's right foot pushes downwardly on the right freadle 12, the right freadle moves downwardly and is guided along the right rectangular post 958" by the right sleeve 962". At the same time, in one embodiment, the right treadle can pivot about its pivot point 330 (i.e., the pivot point between the right U-shaped coupling member 964" or bracket and the right freadle 12). As the right sleeve 962" moves downwardly, the cable 948 is pulled downwardly along the right rectangular post 958". This, in turn, causes the cable 948 to be pulled upwardly along the left rectangular post 958', which pulls the left sleeve 962' upward, thereby imparting an upward force on the left treadle 12.

Conversely, as can be understood from Fig. 106, as the user's left foot pushes downwardly on the left treadle 12, the left freadle moves downwardly and is guided along the left rectangular post 958' by the left sleeve 962'. At the same time, in one embodiment, the left treadle 12 can pivot about its pivot point 330 (i.e., the pivot point between the left U-shaped coupling member 964' or bracket and the left freadle 12).

As the left sleeve 962' moves downwardly, the cable 948 is pulled downwardly along the left rectangular post 958'. This, in turn, causes the cable 948 to be pulled upwardly along the right rectangular post 958", which pulls the right sleeve 962" upward, thereby imparting an upward force on the right freadle 12.

As previously stated, in one embodiment, the freadles 12 are pivotally attached to the U-shaped coupling member 964', 964" or bracket so that the freadles 12 can pivot with respect to the bracket 964', 964" as the bracket fravels vertically up and down the uprights 958', 958". Consequently, in one embodiment, a spring or return force is included in the pivot structure between the bracket and the freadle. The spring biases the freadle into the upmost position, but does allow the treadle to pivot downwardly under load.

For example, in use, as the left foot strikes the left freadle 12 near the pivot point 330, the free end ofthe left freadle deflects (pivots) downwardly from its uppermost position. Since the left foot strikes the freadle at a point relatively close to the pivot connection 330 with the bracket 964', the freadle pivots downwardly based on the moment force applied by the user and resisted by the return, or spring, force.

As the user's left foot moves rearwardly, its distance from the pivot connection 330 increases, and the moment force thus increases, causing the freadle 12 to pivot more downwardly. As the user's left foot begins to move behind the user's body there is generally a weight shift to the right foot, and the load on the left foot starts to decrease. Thus, although the left foot continues to move away from the pivot point 330, thereby increasing the distance at which the load is supplied, the moment force decreases and, as a result, the downwardly deflection ofthe freadle 12 either decreases, stops, or reverses as the left foot moves behind the user.

Once the left foot lifts off the freadle 12, the spring return force causes the freadle 12 to pivot to its upmost position, ready for the next footfall by the left foot. The same process as described above occurs for the right foot and the right treadle 12. The left foot, in the cycle between impact and lift-off, first moves downwardly and rearwardly, with the heel lowering faster than the toe until the foot passes under the person's body. At some point thereafter, the toe and heal begin to lower at the same rate. Eventually, the heel begins rising faster than the toe until lift-off from the freadle 12. In one embodiment, the rear roller 30 of each freadle 12 can operate as the drive roller to drive the tread belt around the rollers ofthe freadle 12. In another embodiment, the front roller 28 of each freadle operates as the drive roller, hi one embodiment, each drive roller has an integral motor within the drive roller for powering the drive roller. In another embodiment, each drive roller is powered by a motor mounted on the respective treadle frame. hi one embodiment, the drive roller may drive the tread belts 18 ofthe freadles 12 in forward or rearward directions. This allows a user to exercise on the machine 10 facing forwardly, or facing rearwardly. Fig. 107: Treadle Rocker Arm Assembly

For a discussion of another manner of interconnecting the treadles 12 together so the freadles 12 displace relative to each other in an alternating manner, reference is now made to Fig. 107, which is an isomefric view ofthe treadle and base frame portion 300 ofthe exercise machine. As indicated in Fig. 107, in one embodiment, the exercise machine has a rocker arm system 970 that provides for opposing motion ofthe left and right freadles 12 relative to one another.

As shown in Fig. 107, in one embodiment, the left and right freadles 12 are interconnected to one another through a rocker arm assembly 970 and pivoting swing am elements 942', 942". As illusfrated in Fig. 107, the frame 14 includes a pair of U-shaped side frame members 972 connected together at the front end by a front frame member 974 and connected together at the rear end by a rear frame member 976.

As indicated in Fig. 107, in one embodiment, each freadle 12 is pivotally connected to a front and rear swing arm 942 and the swing arms are pivotally attached to the respective side frame member 972. A rocker arm 978 is attached to the front frame member 974 through a rocker pivot 980. Left and right tie rods 982', 982"are connected at one end to a bottom end portion ofthe respective left and right swing arms 982', 982". The opposing ends ofthe tie rods 982', 982" are coupled with the rocker arm 978 through ball joints 984, in one embodiment ofthe invention.

As shown in Fig. 107, in one embodiment, a spring 428 is connected between the rear swing arms 942' and the rear legs ofthe side frame members 972. In one embodiment, the spring 428 is positioned along the swing arm 942' so that after the freadle 12 has moved forwardly, the force developed about a portion ofthe spring 428 returns the swing arm 942' to a generally vertical orientation, which thereby returns the freadle 12 to a generally central position.

In one embodiment, each freadle 12 has, as one of its rollers 28, 30, a drive roller that moves the fread belt 18 around the rollers ofthe freadle. In one embodiment, the drive roller is a roller with an integral motor within the roller. In another embodiment, the drive motor is secured to the freadle frame to displace with the treadle frame 52. The drive motor then powers the drive roller via a drive belt or gear arrangement. In yet another embodiment, the drive roller is powered by a motor mounted on the U-shaped frame sfructure 972. Power is fransferred from the frame-mounted motor to the drive roller via a drive belt routed around sheaves on a tension link. In one embodiment, the drive motor or motors may cause the freadle belts 18 to move rearwardly or forwardly as desired by the user. This allows the user to utilize the exercise machine facing forward or facing rearward.

In one embodiment, as the user's right foot presses against the right treadle 12, the right freadle responds by pivoting rearwardly. This causes the right front swing arm 942' to pivot rearwardly, the right tie rod 982" to move rearwardly, the rocker arm 978 to pivot in a clockwise direction (as viewed from above the rocker arm) about the rocker pivot 980, and the left tie rod 982' to move forwardly. Because the left tie rod 982' moves forwardly, the left front swing arm 942" moves in a forward direction, which moves the left freadle 12 in a forward direction. Conversely, as the user's left foot presses against the left freadle 12, the left freadle responds by pivoting rearwardly. This causes the left front swing arm 942" to pivot rearwardly, the left tie rod 982" to move rearwardly, the rocker arm 978 to pivot in a counterclockwise direction (as viewed from above the rocker arm) about the rocker pivot 980, and the right tie rod 982" to move forwardly. Because the right tie rod 982" moves forwardly, the right front swing arm 942" moves in a forward direction, which moves the right freadle 12 in a forward direction. Fig. 108-110: Treadle Adjustment

For a discussion of a manner of attaching the freadles 12 to the base frame 14 so the slope or position ofthe freadles 12 may be adjusted with respect to the base frame 14, reference is now made to Fig. 108, which is an isomefric view ofthe freadle and base frame portion 300 of the exercise machine. As indicated in Fig. 108, in one embodiment, the exercise machine has a slotted flange structure 918 for adjusting the position of a freadle 12 with respect to the base frame 14.

As shown in Fig. 108, in one embodiment, each freadle 12 is pivotally mounted on a pivot rod 330, such as the pivot rods disclosed elsewhere in this specification. The pivot rod 330 has a first end that resides in a slot 984 in a left flange 918 and a second end that resides in a slot 984 in a right flange 918. The flanges 918 are secured to the base frame 14 ofthe exercise machine.

In one embodiment, the pivot rod 330 coaxially aligns with the rotational axis ofthe rear roller 30 of each freadle 12 as the pivot rod 330 extends from the slot 984 in the left flange 918 to the slot 984 in the right flange 918. In another embodiment, the pivot rod 330 coaxially aligns with the rotational axis of the front roller 28 of each treadle. In other embodiments, the pivot rod 330 extends through another portion of each freadle 12, for example the axis of another roller or through the treadle frame 52 at a position between the front roller 28 and the rear roller 30.

As indicated in Fig. 108, the pivot rod 330 may displace along the slots 984 in the flanges 918. A nut 986 attached to at least one ofthe ends of the pivot rod 330 secures the pivot rod within the slots of the flanges. The nut 986 can be rotated by the user to position the pivot rod 330 and fix the freadles 12 in position along the slots 984. As shown in Fig. 108, in one embodiment, each slot 984 is generally arcuate. In other embodiments, other slot shapes can be used, such as straight or angled slots or slots having notches or detents.

As illusfrated in Fig. 108, in one embodiment, a link member 924 is pivotally attached between the flange structure 918 and the pivot rod 330. The link member 924 helps to guide the pivot rod 330 as it displaces along the slot 984 in the flange 918.

By displacing the pivot rod 330 along the slots 984, the slope ofthe treadles 12, relative to the base frame 14, may be adjusted. For example, as the pivot rod 330 is displaced to the extreme forward position along the slots 984 and the slots 984 are arcuate as illusfrated in Fig. 108, the front ends (i.e., the free ends) ofthe freadles 12 will become closer to the base frame 14 (i.e., the slope of the treadles will decrease). Conversely, as the pivot rod 330 is displaced to the extreme rearward position along the slots 984 and the slots 984 are arcuate, the front ends ofthe freadles 12 will become further away from the base frame 14 (i.e., the slope ofthe treadles will increase). Once the desired freadle slope is attained, the nut 986 may be tightened to secure the pivot rod 330 and the freadle 12 in place.

For a discussion of a manner of adjusting the sfroke depth and slope of a freadle 12, reference is now made to Figs. 109 and 110. Fig. 109 is an isometric view ofthe freadle and base frame portion 300 ofthe exercise machine, and Fig. 110 is a side elevation of a slotted flange sfructure 988 depicted in Fig. 109. As illusfrated in Figs. 109 and 110, an arcuate flange structure 988 is used for adjusting the slope of a treadle 12 with respect to the base frame 14 and limiting the angular displacement ofthe treadles 12 about the pivot point 330.

As indicated in Fig. 109, in one embodiment, the rear end ofthe freadles 12 are pivotally attached to the frame 14 by an upwardly extending flange 918, which is connected by a pivot rod 330 or support member extending through the interior ofthe rear rollers 30, coaxially with the pivot axes ofthe rollers. Alternatively, in one embodiment, the pivot rod may extend through a portion ofthe freadle frames 52 such that the freadles pivot 330 about a pivot point ahead ofthe rear rollers 30.

As shown in Figs. 109 and 110, in one embodiment, an arcuately shaped guide flange 988 extends upwardly from the base frame 14 and includes an arcuate slot 984. A pair of positioning elements 990 displaceably resides within each arcuate slot. The positioning elements are for selectively controlling the positioning and movement of a freadle 12.

As illusfrated in Fig. 109, each positioning element 990 includes a stopper 992 attached to a knob 994. The stopper 992 is adapted to come in contact with a portion ofthe outside edge ofthe freadle frame 52, thereby preventing the treadle from displacing past the stopper. The opposing end ofthe positioning element 990 includes a knob 994 that allows the user to tighten the positioning element 990 and fix the location ofthe positioning element 990 within the slot 984 of a guide flange 988. It should be noted that the stoppers 992 in Fig. 109 have been exaggerated with respect to size in order to clearly depict the features ofthe stoppers. In actual practice the stoppers 992 abut against the edge ofthe freadle frame 52 and do not overlap or contact the fread belt 18.

The slot 984 guides the positioning elements 990, and the positioning elements 990 may be located in various positions along the slot 984 ofthe guide flange 988 to limit the angular displacement ofthe freadles 12 about the pivot point 330. For example, by placing the positioning elements 990 in close proximity to each other along the slot 984, the freadle 12 will have a smaller degree of angular displacement about the pivot point 330 as compared to when the positioning elements 990 are placed further apart. Also, by placing the positioning elements 990 higher along the slot 984 , the freadle 12 has a higher average slope over its range of angular displacement as compared to placing the positioning elements 990 lower along the slot 984. Furthermore, if desired, the positioning elements 990 can be put close enough together to hold the freadles 12 in one place. Thus, as can be understood from Fig. 109, the positioning elements 990 may be used to control the stroke of the freadle 12, as well as the treadle's general angle or slope. Fig. Ill: Exercise Machine with Cam for Controlling Rocker Arm

For a discussion of another manner of adjusting the sfroke depth of a freadle 12, reference is now made to Fig. 111. Fig. 111 is an isometric view of a portion of an exercise machine including a pair of cam surfaces 996 for controlling the movement of a rocker arm 112.

As shown in Fig. 111, in one embodiment, a control mechanism 998 is provided for limiting or controlling the extent to which the freadles 12 can move upwardly or downwardly during use. In this embodiment, treadle movement is regulated by controlling the degree to which a rocker arm can pivot.

As illusfrated in Fig. 111, in one embodiment, the confrol mechanism 998 includes a pair of cam elements 1000 attached about a cross support rod 1002 or member that is rotatably attached to the base frame 14. The cam elements 1000 can be adjusted through the rotation of a knob 1004 attached to the cross support rod 1002.

As indicated in Fig. 111, in one embodiment, the rocker arm 112 includes first and second diamond shaped plates 112A, 112B connected together through a cylindrical joining member 112C. The cylindrical joining member 112C is pivotally coupled to a pivot point 120 on the cross support member 114 ofthe base frame 14. A rocker rod 134, 136 is pivotally attached to each end ofthe rocker arm 112, and a freadle 12 is attached to the top of each rocker rod 134, 136. As explained elsewhere in this specification, the rocker rods 134, 136 push up or pull down on the freadles 12 during operation (i.e., as the left rocker rod pushes down on the rocker arm due to the user's foot pushing downwardly on the left freadle, the rocker arm pivots and the right rocker arm pushes upwardly on the right freadle, thereby moving the right freadle upward).

As can be understood from Fig. 111, in one embodiment, the freadle movement can be regulated by the degree to which the rocker arm 112 can pivot about the rocker pivot 120. As shown in Fig. 111, in one embodiment, the degree of rocker arm pivot can be regulated by rotating the knob. As indicated in Fig. 111, in one embodiment, the radius R of each cam element 1000 varies about the circumference ofthe cam element 1000. The portion ofthe cam element 1000 that comes in contact with the edges of the rocker arm 112 will affect the degree to which the rocker arm 112 can pivot upwardly or downwardly. Ifthe knob 1004 is rotated such that the portion ofthe cam element 1000 having a small radius contacts the rocker arm 112, then the rocker arm 112 is freer to pivot upwardly and downwardly. In contrast, ifthe knob 1004 is rotated such that the portion of the cam element 1000 having a large radius contacts the rocker arm 112, then the rocker arm 112 is less free to pivot upwardly and downwardly. In one embodiment, a portion of each cam element 1000 has a radius R sufficiently large to prevent the rocker arm 112 from pivoting upwardly or downwardly at all (i.e., a lockout position). Fig. 112-114: Treadle with Non-Continuous Belt

For a discussion of an embodiment ofthe exercise machine employing a non-continuous fread belt 18, reference is now made to Figs. 112-114. Fig. 112 is a side elevation ofthe front and rear rollers 28, 30 and the tread belt 18 of an exercise machine employing a non-continuous fread belt 18. Fig. 113 is an exploded isomefric view ofthe fread belt 18 and rollers 28, 30 illusfrated in Fig. 112, according to one embodiment. Fig. 114 is an exploded isomefric view ofthe tread belt 18 and rollers 28, 30 illusfrated in Fig. 114, according to another embodiment.

As shown in Figs. 112-114, in one embodiment, a non-continuous fread belt 18 (i.e., fread surface) is dispaceably located above a deck 26 and is attached at a first end to a first roller 28 and at a second end to a second roller 30. Each roller 28, 30 is provided with a spring 1006. The force ofthe springs 1006 maintains the non-continuous fread belt 18 in a centered position (e.g., in one embodiment, the centered position is where the longitudinal length ofthe tread belt 18 generally coincides with the longitudinal center ofthe distance between the first and second rollers 28, 30). As a user's foot moves a fread belt 18 from its normal resting position, either rearwardly or forwardly, the rollers 28, 30 rotate in response to the fread belt movement caused by the movement ofthe user's foot. When the user's foot is removed from the fread belt 18, both springs 1006 return the fread belt to its centered position.

For instance, when the user's foot initially strikes the front part of the non-continuous fread belt 18, the force ofthe user's stride moves the belt 18 rearwardly in opposition to the bias imparted by the springs 1006 on the belt 18. This winds the springs 1006, thereby increasing the energy stored in the springs 1006. When the user's foot is removed from the tread belt 18, the springs 1006 unwind rapidly and, in one embodiment, return the belt 18 to a centered position so that the belt 18 is poised to receive another foot motion from the user.

As indicated in Figs. 112-114, in one embodiment, the front roller 28 securely receives a front edge ofthe non-continuous belt 18 in a slot 1007, and the rear roller 30 securely receives a rear edge ofthe non-continuous belt 18 in a slot 1009. The belt 18 is wound about the front and rear rollers 28, 30 so as to permit a sufficient amount of rearward motion ofthe belt 18 during use (i.e., sufficient to accommodate the strides of various users).

As illusfrated in Fig. 113, in one embodiment, the front roller 28 and the rear roller 30 are pivotally attached to the base frame 14 through a roller securing member 1008 and pin 1010. In one embodiment, the front roller 28 and the rear roller 30 are each provided with a spring 1006 biased to move the belt forwardly. Alternatively, in one embodiment, a single roller, such as the front roller, is provided with a spring biased to move the belt forwardly during use.

As shown in Fig. 113, in one embodiment, the roller securing member 1008 has an elongated rectangular bottom portion 1012 adapted to be secured to the base frame 14 and has a pair of end caps 1014 extending upward from the rectangular bottom 1012. Each end cap 1014 is provided with a pin 1010. Each roller 28, 30 resides between a pair of end caps 1014, and the end of each roller 28, 30 pivotally receives the pin 1010 ofthe adjacent end cap 1014. This permits the roller 28, 30 to pivot or rotate about the pins 1010 within the roller-securing member 1008.

As illusfrated in Fig. 113, in one embodiment, the spring 1006 is a coil spring having a base end 1016 that can be securely attached within the roller-securing member 1008. As the user's foot contacts the belt 18 and moves the belt 18 rearwardly, the front roller 28 rotates in a direction opposing the spring force and the front spring 1006 winds up, and when the user's foot is removed from the belt/treadle surface 18, the spring 1006 quickly unwinds and rotates the roller 28 in a forward motion to return the belt 18 to its original position. The freadle 12 is now poised for receiving another foot motion. One or more freadles 12 of an exercise device can be configured using the non-continuous belts 18 to form freadmill surfaces.

As shown in Fig. 114, in one embodiment, the front roller 28 and the rear roller 30 are pivotally attached to the base frame 14 through a rectangular support plane 1018 having upwardly extending flanges 1020 that provide pivot and support points for the rollers 28, 30. hi one example, a supporting pin 1010 may extend through the rollers 28, 30 or may be integral within the interior ofthe rollers.

In one embodiment, the front roller 28 and the rear roller 30 may each be provided with a spring 1006 biased to move the belt 18 forwardly. An end cap 1014 secures each roller 28, 30 with its spring 1006 along the pivot axis ofthe roller between the flanges 1020. Alternatively, in another embodiment, a single roller 23, such as the front roller, may be provided with a spring 1006 biased to move the belt 18 forwardly during use.

As previously explained, the front roller 28 has a slot 1007 for securely receiving a front edge of a non-continuous belt 18, and the rear roller 30 has a slot 1009 for securely receiving a rear edge of the non-continuous belt 18. In one embodiment, as shown in Fig. 114, a greater amount of belt material is wound about the front roller 28 than the rear roller 30. This permits a sufficient amount of rearward motion ofthe belt 18 during use (i.e., sufficient to accommodate the strides of various users). As the user's foot contacts the belt 18 and moves the belt 18 rearwardly, the front and rear rollers 28, 30 rotate in a direction opposing the spring force, such that when the user's foot is removed from the fread belt 18 (i.e., fread surface), the spring 1006 or springs rotate the roller 28 or rollers 28, 30 in a forward motion to return the belt 18 to its original position. One or more freadles 12 of an exercise device can be equipped to utilize the non-continuous fread belts 18 to form the fread surfaces 18 ofthe exercise machine. Fig. 115: Tubular Frame Treadle with Front Mounting Shocks

Fig. 115 shows a tubular frame exercise device. Each side ofthe frame 14 is generally U- shaped with an upstanding portion 42. Between the upstanding portion a support bar is suspended. The shocks 76 are supported between a bracket at the front ofthe freadles and the support bar.

Although preferred embodiments of this invention have been described above with a certain degree of particularity, those skilled in the art could malce numerous alterations to the disclosed embodiments without departing from the spirit or scope of this invention. All directional references (e.g., upper, lower, upward, downward, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, cloclcwise, and counterclockwise) are only used for identification puφoses to aid the reader's understanding ofthe present invention, and do not create limitations, particularly as to the position, orientation, or use ofthe invention. Joinder references (e.g., attached, coupled, connected, and the like) are to be construed broadly and may include intermediate members between a connection of elements and relative movement between elements. As such, such joinder references do not necessarily infer that two elements are directly connected and in fixed relation to each other. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be inteφreted as illusfrative only and not limiting. Changes in detail or structure may be made without departing from the spirit ofthe invention as defined in the appended claims.

Claims

IT IS CLAIMED:

1. An exercise machine, comprising: a first freadle having a first interior edge; and a second freadle having a second interior edge adjacent to the first interior edge ofthe first freadle; wherein the first and second interior edges include a low friction material.

2. An exercise machine, comprising: a first freadle having a first interior edge; and a second freadle having a second interior edge adjacent to the first interior edge ofthe first freadle; wherein the first and second interior edges define a sliding interface.

3. An exercise machine, comprising: a first treadle having a first interior edge; and a second treadle having a second interior edge adjacent to the first interior edge ofthe first freadle; wherein the first and second interior edges include a set of rollers.

4. An exercise machine, comprising: a first treadle having a moving belt surface; a second treadle having a moving belt surface; and a third freadle positioned between the first and second freadles, wherein the third freadle includes a low frictional top surface.

5. The exercise machine of claim 4, wherein the third treadle is a stationary freadle.

6. An exercise machine, comprising: a first treadle having a first plurality of adjacent, coplanar rollers defining a top surface; and a second treadle having a second plurality of adjacent, coplanar rollers defining a top surface.

7. The exercise machine of claim 6, wherein the first plurality of rollers are interconnected.

8. The exercise machine of claim 7, further comprising a drive mechanism for confrollably rotating the first plurality of rollers.

9. An exercise machine, comprising: a frame; a first treadle having a belt, a freadle frame, and a pair of rollers located on opposite ends of the freadle frame, the belt positioned about the pair of rollers; and a pair of flanges upwardly extending from said frame and a rod extending through the treadle frame and through the pair of flanges.

10. An exercise machine, comprising: a frame; a first freadle having a belt, a freadle frame, and a pair of rollers located on a first and second end ofthe freadle frame, the belt positioned about the pair of rollers; and means for pivotally coupling said freadle frame to the frame at a point between the first and second ends ofthe treadle frame.

11. An exercise machine, comprising: a frame; a first treadle having a belt, a treadle frame, and a set of three rollers defining a triangular shape, the belt positioned about the set of rollers; and means for pivotally coupling the freadle to the frame at a location between the ends of the freadle surface.

12. The exercise machine of claim 11, wherein the set of tliree rollers includes and upper pair of rollers and a lower roller, said lower roller pivotally connected with said frame.

13. An exercise machine, comprising: a frame; a first freadle having a belt, a freadle frame, and a pair of rollers, the belt positioned about the rollers; and a pivot link pivotally coupled to the frame at a first pivot point and pivotally coupled to the freadle at a second pivot point.

14. The exercise machine of claim 13, further comprising: a spring connected between the frame and the freadle frame.

15. The exercise machine of claim 13, wherein as the first treadle is depressed, the freadle moves downwardly and rearwardly relative to the frame.

16. An exercise machine, comprising: a frame; a first freadle having a belt, a treadle frame, and a set of four rollers defining a frapezoid shape, the belt positioned about the four rollers; and means for pivotally coupling the freadle to the frame about a single pivot point.

17. The exercise machine of claim 16, wherein the freadle frame includes an upper frame portion coupled between a top pair of rollers and a lower frame portion coupled between a bottom pair of rollers.

18. The exercise machine of claim 17, wherein the upper and lower frame portions are coupled with a spring.

19. An exercise machine, comprising: a frame; a first freadle having a belt, a freadle frame, and a set of four rollers defining a parallelogram shape, the belt positioned about the four rollers; and means for pivotally coupling the freadle to the frame about a pair of fixed pivot points.

20. The exercise machine of claim 19, wherein the freadle frame includes an upper frame portion coupled between a top pair of rollers and a lower frame portion coupled between a bottom pair of rollers.

21. The exercise machine of claim 20, wherein the upper and lower frame portions are coupled with a spring.

22. An exercise machine, comprising: a frame; a first freadle having a belt, a freadle frame, and a front and rear roller, the belt positioned about the rollers; a pivot link pivotally coupled to the frame at a first pivot point and pivotally coupled to the freadle at a second pivot point; and a torsion spring connected between the frame and the pivot link.

23. The exercise machine of claim 22, wherein at the second pivot point, the pivot link is pivotally attached to the rear roller.

24. The exercise machine of claim 22, wherein at the second pivot point, the pivot link is pivotally attached to the treadle frame.

25. An exercise machine, comprising: a frame; a first treadle having a belt, a treadle frame, and a front and rear roller, the belt positioned about the rollers; a four bar linkage pivotally coupled to the frame at a first pivot point and pivotally coupled to the treadle at a second pivot point; and a biasing spring connected between two bars ofthe linkage.

26. The exercise machine of claim 25, wherein as the first freadle is depressed, the freadle moves downwardly and forwardly relative to the frame.

27. The exercise machine of claim 25, wherein at the second pivot point, the pivot link is pivotally attached to the rear roller.

28. An exercise machine, comprising: a frame including a first and second side support member; a first treadle having a belt, a treadle frame, and a front and rear roller, the belt positioned about the rollers; a set of swing arms pivotally attached between said first side support member and the first freadle frame; a second freadle having a belt, a freadle frame, and a front and rear roller, the belt positioned about the rollers; a set of swing arms pivotally attached between said second side support member and the second freadle frame; and an interconnection means connecting said first freadle to the second treadle, whereby when said first freadle moves rearward, said second freadle moves forward.

29. The exercise machine of claim 28, wherein the interconnection means includes: a first pulley proximate said first freadle; a second pulley proximate said first freadle; a third pulley proximate said second treadle; a fourth pulley proximate said second treadle; an axle fixedly attached between the second and third pulleys; a first cable operatively connecting the first treadle to the second pulley; and a second cable operatively connecting the second freadle to the third pulley.

30. The exercise machine of claim 29, whereby when said first freadle moves rearward, the axle rotates and moves the second freadle forward.

31. An exercise machine, comprising: a frame including a lower frame portion and a pair of vertical posts; a first freadle having a belt, a freadle frame, and a front and rear roller, the belt positioned about the rollers; a first sleeve for slidably connecting the first freadle to the first vertical post; a second sleeve for slidably connecting the second treadle to the second vertical post; a set of pulleys; and a cable connected to said first and second sleeves and connected about said pulleys, so that when the first freadle moves downward, said second freadle moves upward.

32. The exercise machine of claim 31 , wherein the first and second sleeves each include a coupling member defining pivot point connections to the first and second freadles, so that as the freadles move up or down, the freadles can pivot about the pivot points.

33. An exercise machine, comprising: a frame including a first and second side support member; a first treadle having a belt, a freadle frame, and a front and rear roller, the belt positioned about the rollers; a set of swing arms pivotally attached between said first side support member and the first freadle frame; a second freadle having a belt, a freadle frame, and a front and rear roller, the belt positioned about the rollers; a set of swing arms pivotally attached between said second side support member and the second freadle frame; and a rocker arm assembly connecting said first freadle to the second freadle, whereby when said first freadle moves rearward, said second freadle moves forward.

34. The exercise machine of claim 33, wherein the rocker arm pivots about a vertical axis.

35. The exercise machine of claim 33, further comprising: a spring biasingly positioning a first swing arm into a vertical orientation.

36. An exercise machine, comprising: a frame; a first freadle having a belt, a freadle frame, and a pair of rollers located on opposite ends of the freadle frame, the belt positioned about the pair of rollers; and means for pivotally and fixedly coupling said freadle frame to the frame about a plurality of selectable positions.

37. The exercise machine of claim 36, wherein the means for pivotally coupling includes a pair of flanges upwardly extending from said frame and a rod extending through the freadle frame and through the pair of flanges.

38. The exercise machine of claim 37, wherein the pair of flanges include an arcuate slot therethrough.

39. An exercise machine, comprising: a frame; a first treadle pivotally coupled with said frame; and a position limiting element attached to said frame, said positioning limiting element limiting the pivotal movement of said freadle between a first point and a second point.

40. The exercise machine of claim 39, wherein the position limiting element includes a flange upwardly extending from said frame.

41. The exercise machine of claim 40, wherein the flange includes an arcuate slot therethrough.

42. An exercise machine, comprising: a frame; a first and second freadle pivotally coupled with said frame; a rocker arm connecting said first and second treadle; and a control attached to said frame, said control limiting the pivotal movement of said rocker arm.

43. The exercise machine of claim 42, wherein the confrol includes a set of cam elements attached about a cross support bar.

44. The exercise machine of claim 43, wherein the confrol includes a knob for selectively rotating the cam elements to engage the rocker arms.

45. An exercise machine, comprising: at least one freadle having a non-continuous belt, a treadle deck, a treadle frame, and a first and second roller located on opposite ends ofthe treadle frame, the belt extending from the first roller over the deck to the second roller; and at least one spring connected between the first roller and the freadle frame, said spring regulating the location ofthe non-continuous belt relative to the deck.

46. The exercise machine of claim 45, wherein first and second rollers each include a slot for securely receiving an end ofthe belt.

47. An exercise device comprising: a first freadle operably mounted on a frame to pivot with respect to said frame; and a first resistance element operably mounted between said frame and said first freadle, said first resistance element having a mounting position that is selectively movable within a range of mounting positions to adjust a position of said first freadle with respect to said frame.

48. The exercise device according to claim 47, further comprising: a second treadle operably mounted on said frame to, pivot with respect to said frame; and a second resistance element operably mounted between said frame and second freadle, said second resistance element having a mounting position that is selectively movable to adjust a position of said second freadle with respect to said frame.

49. The exercise device as in claim 48, wherein: said first resistance element is mounted to said frame by a first continuous adjustment sfructure to permit continuous adjustment of said mounting position of said first resistance element within said range of mounting positions for said first resistance element; and said second resistance element is mounted by a second continuous adjustment sfructure to said frame to permit continuous adjustment of said mounting position of said second resistance element within said range of mounting positions for said second resistance element.

50. The exercise device as in claim 49, wherein at least one of said continuous adjustment structures is a lead screw.

51. The exercise device as in claim 50, wherein said lead screw is operably connected to a motor to rotate said lead screw.

52. The exercise device as in claim 48, wherein said first resistance element is mounted by a first discrete adjustment sfructure to said frame; and said second resistance element is mounted by a second discrete adjustment sfructure to said frame.

53. The exercise device as claimed in 52, wherein said first and second discrete adjustment structures comprise pop pin structures.

54. The exercise device as claimed in claim 48, wherein said first resistance element is mounted on an adjustment sfructure on said first freadle to selective adjust the mounting position of said first resistance element on said first freadle.

55. The exercise device as claimed in claim 47, wherein said resistance element is a shock.

56. A dual deck exercise device comprising: a first treadle operably mounted to a frame to pivot with respect to said frame, said first freadle including a first continuous fread; a second freadle operably mounted to said frame to pivot with respect to said frame, said second treadle including a second continuous fread; a first motor for producing a driving force for said first continuous fread; and a second motor for producing a driving force for said second continuous fread.

57. A dual deck exercise device as defined in claim 56, further comprising: a first driver roller driven by said first motor, said first driver roller being in contact with said first fread to apply said driving force from said first motor to said first continuous fread; and a second driver roller driven by said second motor, said second driver roller being in contact with said second fread to apply said driving force from said second motor to said second continuous fread.

58. The dual deck exercise device of claim 57, wherein said first motor is synchronized with said second motor to drive said first and second treads at substantially the same speed as each other.

59. The dual deck exercise device of claim 57, wherein said first motor and second motor can be separately controlled to simultaneously drive said first and second freads at different speeds from each other.

60. A freadle assembly for use in an exercise device, the treadle assembly comprising: a frame; an upper deck spaced apart from and generally above said frame; a fread that is slidable across a top surface of said upper deck; and a suspension operably contacting said frame and said upper deck to hold said upper deck in position adjacent to and generally below said fread, said suspension cushioning said upper deck upon deflection of said upper deck towards said frame.

61. The treadle assembly of claim 60, wherein said suspension comprises at least one resilient member inteφosed between said frame and said upper deck.

62. The treadle assembly of claim 60, wherein said suspension comprises a plurality of resilient bumpers inteφosed between said frame and said upper deck.

63. The treadle assembly of claim 62, further comprising rollers rotatably connected to said frame, and wherein said fread is a continuous belt provided around said rollers.

64. An exercise device comprising a pair of the treadles as set forth in claim 63.

65. The treadle assembly as set forth in claim 60, wherein said suspension comprises at least one rigid bumper inteφosed between said frame and said upper deck and at least one resilient bumper inteφosed between said frame and said upper deck.

66. The treadle assembly as set forth in 60, wherein said upper deck is cantilevered with respect to said frame, and wherein said suspension system comprises at least on resilient member inteφosed between said frame and said upper deck.

67. The freadle assembly of claim 60, wherein said suspension comprises: a resilient member inteφosed between said frame and said upper deck, said resilient member contacting a lower surface of said upper deck upon initial deflection of said upper deck towards said frame; and a harder member inteφosed between said frame and said upper deck, said harder member being spaced apart from said lower surface of said upper deck upon initial deflection of said upper deck towards said frame.

68. The treadle assembly of claim 67, wherein said suspension comprises: a plurality of said resilient members, said plurality of resilient member cushioning said initial deflection of said upper deck towards said frame; and a plurality of said harder members, said plurality of harder members acting as spacers to prevent excessive deflection of said upper deck towards said frame.

69. An exercise device comprising: a frame; a first treadle having a restrained end and a free end, said first freadle being pivotally attached to said frame proximate to said restrained end, said freadle including a fread portion formed by a top span of a continuous belt; a motor for driving said belt on said freadle; a first resistance device for opposing pivoting of said first freadle in at least one direction, said first resistance device operably attached between said frame and said freadle such that said freadle slopes downwardly from said restrained end to said free end; a second freadle having a restrained end and a free end, said second freadle being pivotally attached to said frame proximate to said restrained end of said second freadle, said second freadle including a fread portion formed by a top span of a second continuous belt; a second resistance device for opposing pivoting of said second treadle in at least one direction, said second resistance device operably attached between said frame and said second freadle such that said second freadle slopes downwardly from said restrained end to said free end of said second freadle; and wherein said frame includes an upright, and wherein said restrained ends of said first and second treadles are pivotally attached to said upright.

70. The exercise device of claim 69, wherein said frame includes an upright and wherein said first resistance device is attached between said first freadle and said upright.

71. The exercise device of claim 69, wherein said first resistance device resists pivoting of said first freadle in both directions.

72. The exercise device in claim 69, wherein: an interconnect is operably associated with each freadle to cause one treadle to rise while the other one lowers; and said resistance devices do not include a spring return action.

73. The exercise device in claim 69, wherein: said resistance devices include one shock operably associated with each treadle.

74. The exercise device in claim 73, wherein: an interconnect is operably associated with each freadle to cause one freadle to rise while the other one lowers; and said at least one shock does not include a spring return action.

75. A dual deck exercise device comprising: a frame; a first treadle pivotally mounted on said frame; a second freadle pivotally mounted on said frame; a dependency sfructure operably associated with both freadles and mounted to said frame such that when either freadle is pushed down, the other freadle is pushed up; and a resistance mechanism operably associated with said dependency sfructure to provide resistance to movement of said first and second freadles by resisting movement of said dependency structure.

76. An exercise device as claimed in 75, wherein said dependency device is a rocldng arm.

77. An exercise device as claimed in 75, wherein: said resistance mechanism is a rotational brake.

78. An exercise device as claimed in 75, wherein: aid resistance mechanism is an electro-magnetic brake.

79. An exercise device as claimed in 75, wherein: said resistance mechanism is a hydraulic mechanism.

80. An exercise device comprising: a frame, said frame having a range of attachment locations; a first freadle pivotally mounted to said frame to pivot in a generally vertical plane; a first resistance device having a top end and a bottom end, said bottom end of said first resistance element being operably attached to said first freadle, and said top end of said first resistance element being adjustably attached to said frame at a first location within said range of attachment locations; wherein adjustment of said top end of said first resistance element to a different location within said range of attachment locations changes a height of said first freadle; and wherein said first resistance element is attached to said frame by a lead screw mechanism.

81. An exercise device as recited in claim 80,wherein said frame includes a second range of attachment locations, the exercise machine further comprising: a second treadle pivotally mounted to said frame to pivot in a generally vertical plane; a second resistance element having a top end and a bottom end, said bottom end of said second resistance element being operably attached to said second freadle, and said top end of said second resistance element being adjustably attached to said frame at a first location within said second range of attachment locations; and wherein adjustment of said top end of said second resistance element to a different location within said second range of attachment locations changes a height of said second freadle.

82. An exercise device as recited in claim 81, wherein: a dependency device is operably attached between said first and second freadles to cause one treadle to move up when the other treadle is moved down; and wherein each of said resistance elements do not have a spring return feature.

83. An exercise device as recited in claim 81 , wherein adjustment of said first freadle is independent of said second freadle, such that said treadles can be adjusted to different heights.

84. A dual deck exercise device comprising: a frame; a first freadle; a second freadle; a first scissors truss connecting the first freadle to the frame; a second scissors truss connecting the second freadle to the frame; each of said scissors trusses able to be moved between a lower position and an upper position; and each of said scissors trusses having a biasing member to resiliently bias said scissors truss towards said upper position.

85. An exercise device as recited in claim 84, further comprising: a dampener associated with each of said freadles.

86. An exercise device as recited in claim 84, further comprising: a dependency device operably associated between each of said freadles to cause one freadle to rise as the other freadle lowers.

87. An exercise device as recited in claim 84, wherein: said scissor trusses cause each of said treadles to remain parallel to a support surface as each truss moves downwardly.

88. An exercise device as recited in claim 84, wherein said biasing members are placed in tension as said freadles move from said upper positions towards said lower positions.

89. An exercise device as recited in claim 84, wherein said biasing members are placed in compression as said freadles move from said upper positions towards said lower positions.

90. A dampening device for an exercise machine having freadles, said device comprising: a reservoir containing hydraulic fluid divided into first and second chambers by a valve; a plunger in each of said first and second chambers, each of said plungers operably associated with a freadle; and wherein as one plunger is pushed into its respective chamber by said respective freadle, said hydraulic fluid fransfers through said valve to said other chamber and pushes said other plunger and its respective freadle outwardly.

91. A dampening device as defined in claim 90, wherein said valve is adjustable to allow a varying dampening effect.

92. A dampening device as defined in claim 90, wherein said plungers are provided within first and second cylinders, and said first and second cylinders are sealed by a shared cap.

93. A dampening device as defined in claim 92, wherein said cylinders are mounted side- by-side within a housing.

94. A dampening device as defined in claim 93, wherein said cap includes a passage joining said first and second chambers for flow of hydraulic fluid between said first and second chambers.

95. A dampening device as defined in claim 90, wherein said plungers are associated with said respective freadles through a dependency device.

96. A dampening device as recited in claim 90, further comprising a biasing mechanism associated with each freadle for biasing the treadle upward.

97. A dampening device as recited in claim 96 wherein each of said biasing mechanisms comprises a corresponding spring.

98. A dampening device as recited in claim 97, wherein: each of said plungers comprises a corresponding piston; each of said plungers is operably associated with its corresponding freadle by a corresponding connection rod; and wherein said springs are operably connected between a frame ofthe exercise machine and the freadles.

99. An exercise device comprising: a frame; a first treadle pivotally attached to said frame for pivotal movement of said first freadle in a generally vertical plane; a first dampener attached between said frame and said first freadle to resist movement of said freadle; and a first spring attached between said frame and said first freadle to urge said first freadle upwardly.

100. An exercise device as defined in claim 99, further comprising: a second freadle pivotally attached to said frame for pivotal movement of said second freadle in a generally vertical plane; a second dampener attached between said frame and said second freadle to resist movement of said freadle; and a second spring attached between said frame and said first freadle to urge said second freadle upwardly.

101. An exercise device as defined in claim 100, wherein: said first and second springs are elastomeric.

102. An exercise device as defined in claim 101, wherein said first and second springs are stretched by a downward movement of their corresponding first and second treadles.

103. An exercise device as defined in claim 101, wherein said first and second springs are compressed by a downward movement of their corresponding first and second treadles.

104. An exercise device as defined in claim 100, wherein said first dampener resists downward movement of said first treadle.

105. An exercise device as defined in claim 100, wherein a resistance level for said first dampener is adjustable.

106. An exercise device as defined in claim 100, wherein said first dampener resists upward movement of said first freadle, but wherein said resistance to said upward movement of said first freadle is overcome by said upward urging of said first spring.

107. A dual deck exercise device comprising: a frame; a left freadle pivotally attached to said frame and having a front and rear left treadle rollers with a left fread extending around said left freadle rollers; a right freadle pivotally attached to said frame and having a front and rear right freadle rollers with a right fread extending around said right freadle rollers; a left drive roller mechanism exterior to the left fread and to drive said left fread; and a right drive roller mechanism exterior to the right fread and to drive said right fread.

108. The exercise device of claim 107, wherein: said left drive roller mechanism is in frictional engagement with said left fread; and said right drive roller mechanism is in frictional engagement with said right tread.

109. The exercise device of claim 107, wherein: said left drive roller mechanism is in frictional engagement with one of said front and rear left freadle rollers; and said right drive roller mechanism is in frictional engagement with one of said front and rear right rollers.

110. The exercise device of claim 107, wherein: said left drive roller mechanism is in positive engagement with one of said front and rear left freadle rollers; and said right drive roller mechanism is in positive engagement with one of said front and rear right rollers.

111. The exercise device of claim 107 wherein said left and right drive roller mechanisms comprise a common drive roller shared by both drive roller mechanisms.

112. The exercise device of claim 111, wherein said common drive roller is in frictional engagement with said left tread and said right tread.

113. The exercise device of claim 111, wherein said common drive roller is in frictional engagement with on of said front and rear left freadle rollers and one of said front and rear right freadle rollers.

114. The exercise device of claim 111, wherein said common drive roller is in positive engagement with on of said front and rear left freadle rollers and one of said front and rear right freadle rollers.

115. The exercise device of claim 111, wherein said common drive roller is provided with a control mechanism in order to vary a speed of said left and right treads.

116. An exercise device, comprising: a frame; a freadle assembly pivotally attached to said frame by a pivotal connection; and an upright attached to said frame; wherein said freadle assembly is operative to pivot about said pivotal connection to a storage position substantially parallel to said upright.

117. The exercise device as set forth in claim 116, further comprising: a side rail pivotally attached to said upright by a side rail pivot; and wherein said side rail is operable to pivot about said side rail pivot into a storage position.

118. The exercise device as set forth in claim 116, further comprising a latching mechanism for retaining said freadle assembly in said storage position.

119. The exercise device as set forth in claim 116, wherein the exercise device is free standing on said frame with said treadle assembly and said upright in a generally vertical orientation when said freadle assembly is in said storage position.

120. The exercise device as set forth in claim 119, where said freadle assembly is rotated to an over-center orientation when said treadle assembly is in said storage position.

121. An exercise device, comprising: a base frame with a freadle assembly pivotally attached thereto; an upright pivotally attached to said base frame by an upright storage pivot; and a side rail pivotally attached to said upright by a side rail pivot; wherein said side rail is operable to pivot about said side rail pivot into a storage position; and wherein said upright is operable to pivot about said upright storage pivot into a storage position.

122. The exercise device of claim 121, further comprising: a lateral support operably attached to said base frame by a base frame pivot; and wherein said base frame is operable to pivot about said base frame pivot into a laterally supported storage position.

123. The exercise device of claim 121, wherein the exercise device is free standing on a front end of said base frame and a bottom portion of said upright with said base frame and said upright in a generally vertical orientation when said upright is pivoted into said storage position.

124. An exercise device comprising: a rear base frame having a treadle assembly attached to thereto; a front base frame pivotally attached to a front portion of said rear base frame at a base frame pivot; an upright attached to said front base frame; and wherein said rear base frame is pivotal about said base frame to pivot between an operational position wherein said front base frame is generally transverse to said upright and a storage position wherein said rear base frame is proximate to and generally parallel with said upright.

125. The exercise device of claim 124 wherein said freadle assembly is attached to a rear portion of said rear base frame.

126. The exercise device as set forth in claim 124, further comprising: a side rail pivotally attached to said upright by a side rail pivot; and wherein said side rail is operable to pivot about said side rail pivot into a storage position.

127. The exercise device as set forth in claim 124, wherein the exercise device is free standing on said front base frame with said rear base frame and said upright in a generally vertical orientation when said rear base frame is in said storage position.

128. The exercise device as set forth in claim 127, wherein said rear base frame is rotated to an over-center orientation when said rear base frame is in said storage position.

129. A an exercise device, comprising: a main frame; a housing fixedly attached to said main frame; and at least one freadle attached to said main frame; wherein the height of said housing at least equals a height of said freadle during operation of said freadle.

130. The exercise device of claim 129, further comprising a resistive element operationally attached between said freadle and said housing.

131. The exercise device of claim 129, wherein said housing is of single-piece constmction.

132. The exercise device of claim 129, further comprising a return element operationally attached between said treadle and said housing.

133. An exercise apparatus comprising: a frame; first and second movable belt freadle assemblies pivotally mounted to the frame; a first dampening device coupled between the frame and the first treadle assembly; a first biasing device coupled between the frame and the first freadle assembly; a second dampening device coupled between the frame and the first freadle assembly; and a second biasing device coupled between the frame and the first treadle assembly.

134. The exercise apparatus of claim 133 wherein the first and second movable belt freadle assemblies comprise respective drive rollers; further comprising: a motor mounted to the frame; a drive shaft, the drive rollers being affixed to the drive shaft and the drive shaft being rotatably coupled to the frame to provide a pivot for the first and second freadle assemblies; and a torque fransfer mechanism coupling the drive shaft to the motor.

135. The exercise apparatus of claim 133 wherein: the frame comprises an upright member; and the first and second movable belt freadle assemblies are pivotally mounted to the upright member.

136. The exercise apparatus of claim 135 wherein the upright member is a single elongated stracture, the first and second movable belt freadle assemblies being mounted on respective opposing sides ofthe structure.

137. The exercise apparatus of claim 135 wherein the upright member comprises two spaced-apart elongated sfructures, the first and second movable belt treadle assemblies being mounted between the sfructures.

138. The exercise apparatus of claim 135 wherein the first and second movable belt treadle assemblies are pivotally mounted to the upright member with a fixed pivot.

139. The exercise apparatus of claim 135 wherein the first and second movable belt treadle assemblies are pivotally mounted to the upright member with a variable pivot.

140. The exercise apparatus of claim 133 wherein: the first dampening device and the first biasing device are integrated into a first unitary device coupled between the upright and the first treadle assembly; and the second dampening device and the second biasing device are integrated into a second unitary device coupled between the upright and the first freadle assembly.

141. The exercise apparatus of claim 133 wherein the first and second movable belt freadle assemblies comprise: respective belts having respective upper surfaces for friction engagement by a user's feet; and a drive mechanism for driving the upper surfaces ofthe belts in a direction away from where the first and second movable belt freadle assemblies are pivotally mounted to the frame.

142. The exercise apparatus of claim 141 wherein: the frame comprises an upright member; the pivot mechanism has a single pivot axis; and the first and second movable belt freadle assemblies are pivotally mounted to the upright member along the pivot axis.

143. The exercise apparatus of claim 133 wherein the first and second movable belt freadle assemblies comprise: respective belts having respective upper surfaces for friction engagement by a user's feet; and a drive mechanism for driving the upper surfaces ofthe belts in a direction toward where the first and second movable belt freadle assemblies are pivotally mounted to the frame.

144. The exercise apparatus of claim 143 wherein: the frame comprises an upright member; the pivot mechanism has a single pivot axis; and the first and second movable belt treadle assemblies are pivotally mounted to the upright member along the pivot axis.

145. An exercise device comprising: a pair of freadle assemblies operably connected to a frame for complementary opposing movement in generally vertical planes as a user steps on a fread portion of each treadle assembly; and wherein each fread portion is formed by a separate movable belt; a driver mechanism for moving said movable belts with respect to said treadle assemblies; wherein said driver mechanism can drive said belts simultaneously with said treadle assemblies moving in complementary fashion with respect to each other; and wherein said freadle assemblies can be locked in a fixed orientation relative to said frame such that said exercise device can function as a freadmill.

146. An exercise device comprising: a pair of freadle assemblies operably connected to a frame for complementary opposing movement in generally vertical planes as a user steps on a fread portion of each freadle assembly; and wherein each fread portion is formed by a separate movable belt; a driver mechanism for moving said movable belts with respect to said treadle assemblies; wherein said driver mechanism can drive said belts simultaneously with said treadle assemblies moving in complementary fashion with respect to each other; and wherein said movable belts can be locked in a fixed position relative to said freadle assemblies such that the exercise device can function as a stepper.

147. An exercise device comprising: a pair of freadle assemblies operably connected to a frame for complementary opposing movement in generally vertical planes as a user steps on a fread portion of each freadle assembly; and wherein each fread portion is formed by a separate movable belt; a driver mechanism for moving said movable belts with respect to said freadle assemblies; wherein said driver mechanism can drive said belts simultaneously with said treadle assemblies moving in complementary fashion with respect to each other; and wherein said freadle assemblies can be locked in a fixed orientation relative to said frame such that said exercise device can function as a freadmill; and wherein said movable belts can be locked in a fixed position relative to said treadle assemblies such that the exercise device can function as a stepper.

148. An exercise apparatus comprising: a frame; a first movable belt treadle assembly pivotally mounted to the frame; a second movable belt freadle assembly pivotally mounted to the frame; a rocker arm pivotally mounted to the frame and having a first end and a second end; a first tie rod having a first end coupled to the first end of the rocker arm and a second end coupled to the first freadle assembly; a second tie rod having a first end coupled to the second end of the rocker arm and a second end coupled to the second treadle assembly; wherein the first end ofthe first tie rod is coupled to the first end ofthe rocker arm by a universal joint, and the second end ofthe first tie rod is coupled to the first freadle assembly by a universal joint; and the first end ofthe second tie rod is coupled to the second end ofthe rocker arm by a universal joint, and the second end ofthe second tie rod is coupled to the second freadle assembly by a universal joint.

149. The exercise apparatus of claim 148, wherein: the second end ofthe first tie rod is coupled to the first freadle assembly at a side frame member on the first freadle assembly; and the second end ofthe second tie rod is coupled to the second freadle assembly at a side frame member on the second treadle assembly.

150. An exercise apparatus comprising: a frame; a first movable belt freadle assembly pivotally mounted to the frame; a second movable belt treadle assembly pivotally mounted to the frame; a rocker arm pivotally mounted to the frame and having a first end and a second end; a first tie rod having a first end coupled to the first end of the rocker arm and a second end coupled to the first freadle assembly; a first biasing device having a first end coupled to the first end ofthe rocker arm and a second end coupled to the frame; a second tie rod having a first end coupled to the second end ofthe rocker arm and a second end coupled to the second freadle assembly; and a second biasing device having a first end coupled to the second end ofthe rocker arm and a second end coupled to the frame.

151. An exercise apparatus comprising: a frame; a first movable belt freadle assembly pivotally mounted to the frame; a first biasing device operably provided between the frame and the first movable belt treadle assembly for acting on the first movable belt freadle assembly with a push-up biasing force; a second movable belt treadle assembly pivotally mounted to the frame; and a second biasing device operably provided between the frame and the second moveable belt assembly for acting on the second movable belt freadle assembly with a push-up biasing force.

152. The exercise apparatus of claim 151 wherein the first and second biasing devices have fixed biasing characteristics.

153. The exercise apparatus of claim 152 wherein: the frame comprises a base frame member; and the first and second biasing devices are directly coupled to the base frame member.

154. The exercise apparatus of claim 151 wherein the first and second biasing devices have variable biasing characteristics.

155. The exercise apparatus of claim 154 wherein each ofthe first and second biasing devices comprises a spring and a variable length mechanism integrated with the spring to obtain the variable biasing characteristics thereof.

156. The exercise apparatus of claim 154 wherein the first and second biasing devices comprise respective springs and a common variable length mechanism to obtain the variable biasing characteristics thereof.

157. The exercise apparatus of claim 153, wherein the first and second biasing devices comprise helical springs.

158. The exercise apparatus of claim 157, wherein the helical springs bear against the base frame at one end and against a flange provided on their respective freadle assemblies on an other end.

159. An exercise apparatus comprising: a frame; a first movable fread freadle assembly pivotally mounted to the frame; a second movable tread freadle assembly pivotally mounted to the frame; and a brake-based dampening assembly for dampening downward rotation of said movable tread freadle assemblies coupled to the frame having a first belt end coupled to the first movable fread freadle assembly and a second belt end coupled to the second movable fread freadle assembly.

160. The exercise apparatus of claim 159 wherein the brake-based dampening assembly comprises: a single continuous dampening belt, the first and second belt ends being ends ofthe continuous dampening belt; a brake; a differential freewheel coupled to the brake and having a first side and a second side; a pulley system for guiding the continuous dampening belt, the pulley system having a first pulley coupled to the first side ofthe differential freewheel, and a second pulley coupled to the second side ofthe differential freewheel.

161. The exercise apparatus of claim 159 wherein the brake-based dampening assembly comprises: a single continuous dampening belt, the first and second belt ends being ends ofthe continuous dampening belt; a brake; and a pulley system for guiding the continuous dampening belt, the pulley system having a pulley coupled to the brake.

162. The exercise apparatus of claim 159 wherein the brake-based dampening assembly comprises: a first dampening belt, the first belt end being an end ofthe first dampening belt; a second dampening belt, the second belt end being an end ofthe second dampening belt; a brake; a differential freewheel coupled to the brake and having a first side and a second side; a first pulley system for guiding the first dampening belt, the first pulley system having a first pulley coupled to the first side ofthe differential freewheel; and a second pulley system for guiding the second dampening belt, the second pulley system having a second pulley coupled to the second side of the differential freewheel.

163. The exercise apparatus of claim 159 wherein the brake-based dampening assembly comprises: a first dampening belt, the first belt end being an end ofthe first dampening belt; a second dampening belt, the second belt end being an end of the second dampening belt; a first brake; a second brake; a first pulley system for guiding the first dampening belt, the first pulley system having a first pulley coupled to the first brake; and a second pulley system for guiding the second dampening belt, the second pulley system having a second pulley coupled to the second side ofthe differential freewheel.

164. The exercise apparatus of claim 159, further comprising an interconnect device such that when either ofthe movable belt treadle assemblies is pushed down, the other freadle assembly is correspondingly pushed up.

165. The exercise device of claim 164, wherein said dampening of said downward rotation of said freadle assemblies by said brake-based dampening assembly is provided by a resistance force applied to an upward rotation of said treadle assemblies and fransmitted through said interconnection device.

166. An exercise apparatus comprising: a frame; a first movable fread freadle assembly pivotally mounted to the frame; a second movable fread freadle assembly pivotally mounted to the frame; and a single continuous dampening belt having a first end and a second end, the first end being coupled to the first movable fread treadle assembly and the second end coupled to the second movable fread treadle assembly; a flywheel; a differential freewheel coupled to the flywheel and having a first side and a second side; and a pulley system for guiding the continuous dampening belt, the pulley system having a first pulley coupled to the first side ofthe differential freewheel, and a second pulley coupled to the second side ofthe differential freewheel.

167. An exercise apparatus comprising: a frame; a first movable tread treadle assembly pivotally mounted to the frame; a second movable tread freadle assembly pivotally mounted to the frame; and a single continuous dampening belt having a first end and a second end, the first end being coupled to the first movable tread freadle assembly and the second end coupled to the second movable fread freadle assembly; a differential flywheel having a first side and a second side; and a pulley system for guiding the continuous dampening belt, the pulley system having a first pulley coupled to the first side of the differential flywheel, and a second pulley coupled to the second side ofthe differential flywheel.

168. An exercise apparatus comprising: a frame; first and second movable fread treadle assemblies pivotally mounted to the frame; a first biasing mechanism having a support member disposed on the first movable fread freadle assembly and a resilient member coupled to the frame; and a second biasing mechanism having a support member disposed on the second movable tread freadle assembly and a resilient member coupled to the frame.

169. The exercise apparatus of claim 168 further comprising a flat spring coupled to the frame at generally the center thereof to establish a first arm and a second arm, wherein: the support member ofthe first biasing mechanism comprises a first rigid protrusion from the first movable fread freadle assembly; the resilient member ofthe first biasing mechanism comprises the first arm ofthe flat spring; the support member ofthe second biasing mechanism comprises a second rigid protrusion from the second movable fread treadle assembly; and the resilient member ofthe second biasing mechanism comprises the second arm ofthe flat spring;

170. The exercise apparatus of claim 168 further comprising a leaf spring coupled to the frame to present a concave aspect to the first and second movable fread treadle assemblies and to establish a first arm and a second arm, wherein: the support member ofthe first biasing mechanism comprises a first surface associated with the first movable fread freadle assembly; the resilient member ofthe first biasing mechanism comprises the first arm ofthe leaf spring; the support member ofthe second biasing mechanism comprises a second surface associated with the second movable fread treadle assembly; and the resilient member ofthe second biasing mechanism comprises the second arm ofthe leaf spring.

171. The exercise apparatus of claim 168 further comprising a leaf spring coupled to the frame to present a convex aspect to the first and second movable fread freadle assemblies and to establish a first arm and a second arm, wherein: the support member ofthe first biasing mechanism comprises a first surface associated with the first movable fread freadle assembly; the resilient member of the first biasing mechanism comprises the first arm of the leaf spring; the support member ofthe second biasing mechanism comprises a second surface associated with the second movable fread treadle assembly; and the resilient member ofthe second biasing mechanism comprises the second arm ofthe leaf spring.

172. The exercise apparatus of claim 168 further comprising a multiple section torsion spring coupled to the frame at several locations and having a first torsion spring section and a second torsion spring section, wherein: the rigid member ofthe first biasing mechanism comprises a first surface associated with the first movable fread freadle assembly; the resilient member of the first biasing mechanism comprises a linear section ofthe torsion spring extending from the first torsion spring section; the support member ofthe second biasing mechanism comprises a second surface associated with the second movable fread freadle assembly; and the resilient member of the first biasing mechanism comprises a linear section of the torsion spring extending from the second torsion spring section.

173. The exercise apparatus of claim 168 further comprising a flat spring mounted on the frame and having at least a first prong and a second prong disposed toward the first and second movable fread freadle assemblies, wherein: the support member ofthe first biasing mechanism comprises a first surface associated with the first movable fread freadle assembly; the resilient member ofthe first biasing mechanism comprises the first prong; the support member of the second biasing mechanism comprises a second surface associated with the second movable fread freadle assembly; and the resilient member ofthe first biasing mechanism comprises the second prong.

174. An exercise apparatus comprising: a frame; first and second movable fread treadle assemblies pivotally mounted to the frame; a first cushioning mechanism having a rigid member and a resilient member disposed between the frame and the first movable fread treadle assembly; and a second cushioning mechanism having a rigid member and a resilient member disposed between the second movable fread freadle assembly and the frame.

175. The exercise apparatus of claim 174 wherein: the rigid member ofthe first cushioning mechanism comprises a rigid protrusion from the first movable fread treadle assembly; the resilient member of the first cushioning mechanism comprises a first soft rubber bumper coupled to the frame; the rigid member ofthe second cushioning mechanism comprises a rigid protrusion from the second movable fread freadle assembly; and the resilient member ofthe second cushioning mechanism comprises a second soft rubber bumper coupled to the frame.

176. An exercise apparatus comprising: a frame; a first movable belt freadle assembly having a first belt, a first drive roller, and first and second rollers; wherein the first drive roller and the first and second rollers are disposed in a first generally inverted friangular arrangement with the first drive roller being at the apex ofthe first triangular arrangement; wherein the first belt is disposed about the first drive roller and the first and second rollers; wherein the first movable belt freadle assembly is pivotally mounted to the frame in proximity to the first drive roller; a second movable belt freadle assembly having a second belt, a second drive roller, and third and fourth rollers; wherein the second drive roller and the third and fourth rollers are disposed in a second generally inverted friangular arrangement with the second drive roller being at the apex of the second triangular arrangement; wherein the second belt is disposed about the second drive roller and the third and fourth rollers; and wherein the second movable belt freadle assembly is pivotally mounted to the frame in proximity to the second drive roller.

177. The exercise apparatus of claim 176 further comprising: first and second pivot brackets attached to the frame; a motor coupled to the frame; a drive shaft, the first and second drive rollers being affixed to the drive shaft and the drive shaft being rotatably coupled to the pivot brackets to provide a pivot for the first and second treadle assemblies; and a torque fransfer mechanism coupling the drive shaft to the motor.

178. The exercise apparatus of claim 176 further comprising: a first dampening device coupled between the frame and the first movable belt treadle assembly; a first biasing device coupled between the frame and the first movable belt freadle assembly; a second dampening device coupled between the frame and the second movable belt freadle assembly; a second biasing device coupled between the frame and the second movable belt treadle assembly; and a reciprocating linkage coupled between the first movable belt treadle assembly and the second movable belt freadle assembly.

179. The exercise apparatus of claim 178 wherein: the frame comprises an upright; the first dampening device and the first biasing device are integrated into a first unitary device coupled between the upright and the first movable belt freadle assembly; and the second dampening device and the second biasing device are integrated into a second unitary device coupled between the upright and the second movable belt treadle assembly.

180. An exercise apparatus comprising: a frame; a first freadle assembly pivotally coupled to the frame and having at least a first front roller and a first rear roller, and a first movable belt disposed about the first front roller and the first rear roller, a first step area being defined on the first movable belt between the first front roller and the first rear roller, and a deck being absent from the first step area; and a second treadle assembly pivotally coupled to the frame and having at least a second front roller and a second rear roller, and a second movable belt disposed about the second front roller and the second rear roller, a second step area being defined on the second movable belt between the first front roller and the first rear roller, and a deck being absent from the second step area.

181. The exercise apparatus of claim 180 wherein: the first movable belt comprises reinforced edges; and the second movable belt comprises reinforced edges.

182. The exercise apparatus of claim 181, wherein said first and second movable belts are placed in tension between said reinforced edges.

183. The exercise apparatus of claim 180, further comprising a first biasing device coupled between the frame and the first treadle assembly; and a second biasing device coupled between the frame and the second freadle assembly.

184. The exercise apparatus of claim 180 further comprising: a motor mounted to the frame; a drive shaft, the first and second front rollers being affixed to the drive shaft and the drive shaft being rotatably coupled to the frame to provide a common pivot axis for the first and second freadle assemblies; and a torque transfer mechanism coupling the drive shaft to the motor.

185. The exercise apparatus of claim 180 further comprising: a motor mounted to the frame; a drive shaft, the first and second rear rollers being affixed to the drive shaft and the drive shaft being rotatably coupled to the frame to provide a common pivot axis for the first and second freadle assemblies; and a torque fransfer mechanism coupling the drive shaft to the motor.

186. An exercise apparatus comprising: a frame; a first freadle assembly pivotally coupled to the frame and having at least a first front roller and a first rear roller, a first movable belt disposed about the first front roller and the first rear roller, and a first deck having a first user-selectable position in proximity to a first step area defined between the first front roller and the first rear roller and a second user-selectable position removed from the first step area; and a second treadle assembly pivotally coupled to the frame and having at least a second front roller and a second rear roller, a second movable belt disposed about the second front roller and the second rear roller, and a second deck having a first user-selectable position in proximity to a second step area defined between the second front roller and the second rear roller and a second user- selectable position removed from the second step area.

187. The exercise apparatus of claim 186, further comprising a first biasing device coupled between the frame and the first treadle assembly; and a second biasing device coupled between the frame and the second freadle assembly.

188. The exercise apparatus of claim 186 wherein: the first movable belt comprises reinforced edges; and the second movable belt comprises reinforced edges.

189. An exercise machine, comprising a first treadle, a second freadle and a low friction surface located between said treadles.

190. The exercise machine of claim 189, wherein the low friction surface includes a set of rollers.

191. The exercise machine of claim 189, wherein the low friction surface includes a slidable surface.

192. The exercise machine of claim 191, wherein the slidable surface is nylon or Teflon.

193. The exercise machine of claim 191, wherein the slidable surface is lubricated.

194. The exercise machine of claim 189, further comprising a third freadle and wherein the low friction surface is a portion ofthe third freadle.

195. The exercise machine of claim 194, wherein the low friction surface includes a set of rollers.

196. The exercise machine of claim 194, wherein the low friction surface includes a slidable surface.

197. The exercise machine of claim 196, wherein the slidable surface is nylon or Teflon.

198. The exercise machine of claim 196, wherein the slidable surface is lubricated.

199. The exercise machine of claim 194, wherein the third freadle is biased in an upward position.

200. The exercise machine of claim 194, wherein the third treadle altematingly tracks the first and second freadles between a highest treadle displacement point and a point midway between the highest freadle displacement point and a lowest treadle displacement point

201. The exercise machine of claim 189, wherein the first treadle includes a first edge, the second freadle includes a second edge adjacent to the first edge, and the low friction surface includes at least a portion of one of said edges.

202. A protective guard for an exercise apparatus having a first treadle assembly and a second freadle assembly, the protective guard comprising: a base shroud having at least one freadle aperture; a first freadle shroud connected with said first freadle assembly; a second freadle shroud connected with said second freadle assembly; and wherein said first freadle shroud and said second treadle shroud enclose areas between said first freadle assembly, said second treadle assembly, and said base shroud.

203. The protective guard of claim 202, wherein said a least one treadle aperture includes a first freadle aperture and a second freadle aperture.

204. The protective guard of claim 202, wherein said first treadle shroud includes a first outside side shield, a first front side shield, and a first inside side shield; wherein said second freadle shroud includes a second outside side shield, a second front side shield, and a second inside side shield; and wherein said first inside side shield is adjacent to said second inside side shield.

205. The protective guard of claim 202, wherein said base shroud is defined by a front portion, a rear portion, a left portion having a plurality of left side shield fracks, a right portion having a plurality of right side shield tracks, and a top portion; wherein said first treadle shroud includes a first outside side shield and a first inside side shield, said first outside side shield having a first plurality of fracks; wherein said second treadle shroud includes a second outside side shield and a second inside side shield, said second outside side shield having a second plurality of tracks; wherein said first plurality of fracks slidingly engage said plurality of right side shield tracks; and wherein said second plurality of fracks slidingly engage said plurality of left side shield tracks.

206. The protective guard of claim 202, further comprising: a center shield between said first freadle assembly and said second freadle assembly; and wherein said center shield is pivotally supported on said exercise apparatus by a center drive bracket and a spring.

207. A protective guard for an exercise apparatus having a first treadle assembly and a second freadle assembly, the protective guard comprising: a base shroud defined by a right side portion, a left side portion, and a rear side portion; a first freadle shroud connected with said first freadle assembly; and a second treadle shroud connected with said second freadle assembly.

208. The protective guard of claim 207, wherein said first freadle shroud includes a first outside side shield, a first front side shield, and a first inside side shield; wherein said second treadle shroud includes a second outside side shield, a second front side shield, and a second inside side shield; and wherein said first inside side shield and said second inside side shield are connected with a flexible shield.

209. The protective guard of claim 207, wherein said first treadle shroud includes a first outside side shield, a first front side shield, and a first inside side shield; wherein said second freadle shroud includes a second outside side shield, a second front side shield, and a second inside side shield; and wherein said first inside side shield is adjacent to said second inside side shield.

210. The protective guard of claim 207, wherein said base shroud is further defined by a first front portion and a second front portion; wherein said first front portion is partially enclosed by said first freadle shroud when said first treadle assembly is in a first downward position; and wherein said second front portion is partially enclosed by said second freadle shroud when said second freadle assembly is in a second downward position.

211. The protective guard of claim 210, wherein a plurality of tracks on said first front portion engage a plurality of tracks on said first treadle shroud; and wherein a plurality of fracks on said second front portion engage a plurality of tracks on said second freadle shroud.

212. The protective guard of claim 210, further comprising: a first accordion pleated shroud connected with said first freadle shroud and said base shroud; and a second accordion pleated shroud connected with said second treadle shroud and said base shroud.

213. The protective guard of claim 207, wherein said base shroud is further defined by a front portion and a top portion; wherein a first accordion pleated shroud is connected with said first freadle shroud and said top portion of said base shroud; wherein a second accordion pleated shroud is connected with said second freadle shroud and said top portion of said base shroud; and wherein a center shield is adjacent to said first treadle shroud and said second freadle shroud.

214. The protective guard of claim 207, wherein said base shroud is further defined by a front portion; wherein a first multi-fold shroud is connected with said first freadle shroud and said base shroud; and wherein a second multi-fold shroud is connected with said second freadle shroud and said base shroud.

215. The protective guard of claim 207, further comprising: a center shield between said first freadle assembly and said second freadle assembly; and wherein said center shield is pivotally supported on said exercise apparatus by a center drive bracket and a spring.

216. An adjustable length treadle assembly for an exercise apparatus comprising: a freadle frame having a first side tube slidingly engaged with a second side tube, and a third side tube slidingly engaged with a fourth side tube; a first roller connected with said first side tube and said third side tube; a second roller connected with said second side tube and said fourth side tube; an endless freadle belt between said first roller and said second roller; and a belt deck having a first section connected with said first side tube and said third side tube, a second section connected with said second side tube and said fourth side tube, and at least one removable third section, wherein said at least one removable third section is engaged with and positioned between said first section and said second section.

217. An adjustable length freadle assembly for an exercise apparatus comprising: a freadle frame having a first side tube slidingly engaged with a second side tube, and a third side tube slidingly engaged with a fourth side tube; a first roller connected with said first side tube and said third side tube; a second roller connected with said second side tube and said fourth side tube; an endless freadle belt between said first roller and said second roller; and a belt deck having a first section, a second section, and at least one third section, wherein said at least one third section is removably positioned between said first section and said second section.

218. A freadle assembly for an exercise apparatus comprising: a treadle frame having an adjustable length; a first roller connected with said freadle frame; a second roller connected with said treadle frame; an endless freadle belt between said first roller and said second roller; and a belt deck having a first section and at least one second section, wherein said at least one second section is removably positioned between said first section and said second roller.

219. An adjustable length freadle assembly for an exercise apparatus comprising: a freadle frame having a selectively extendable and retractable frame; a freadle belt operably engaged to pass around the freadle frame; and a belt deck having an adjustable length to comport with the adjustment ofthe treadle frame.

220. An apparatus for preventing freadle motion in an exercise machine, comprising: a pedal; a bar affixed to the pedal; a pivot at least partially received within said bar; a pivot stmcture engaging said pivot and affixed to a base of said exercise machine, said pivot pivoting within said pivot sfructure; a locking tab structure operationally connected to said bar and operative to engage a motion- restricting element formed on an underside of said treadle, said motion-restricting element preventing motion when said locking tab sfructure engages said motion-restricting element.

221. The apparatus of claim 220, wherein the locking tab sfructure comprises: at least one locking tab; a lock upright affixed at an angle to said at least one locking tab; and a hinge about which the lock upright rotates.

222. The apparatus of claim 221, wherein said motion-restricting element comprises a channel.

223. The apparatus of claim 220, further comprising a bar slot formed in said bar; wherein said pivot is at least partially received within said bar slot; and said pivot moves along said bar slot when said pedal is depressed.

224. The apparatus of claim 220, further comprising a pivot slot formed in said base of said exercise machine; and wherein said pivot structure slides along said pivot slot when said pedal is depressed.

225. An apparatus for preventing treadle motion in an exercise machine, comprising: a pedal; a bar affixed to the pedal and defining a bar slot therein; a pivot at least partially received within said bar; a lockout wheel; a wheel rod extending from the lockout wheel and at least partially received within said bar slot; a lockout cam operative to engage said freadle to prevent motion; and an axle operatively connecting said wheel rod to said lockout cam.

226. An apparatus for preventing freadle motion in an exercise machine, comprising: a slider handle; a slider bar affixed to said slider handle; a slider support affixed to said exercise machine, said slider bar passing through said slider handle; and a slider key affixed to said slider bar.

227. An exercise device, comprising: a handle bar; a freadle; and an interconnect operationally attaching said handle bar to said freadle, said interconnect associating a handle bar motion to a freadle motion.

228. The device of claim 227, wherein: said interconnect is a solid member; said freadle motion occurs laterally; and the lateral motion of said freadle drives a lateral handle bar motion.

229. The device of claim 228, wherein said interconnect is a solid member; said handle bar motion occurs laterally; and the lateral motion of said handle bar drives a treadle motion.

230. The device of claim 228, wherein: said interconnect comprises an element chosen from the group comprising a one-way bearing and a ratchet-and-pawl mechanism; said motion of said handle bar is a back and forth lateral motion; and said association of said motion of said handle bar to said freadle motion comprises: imparting a counter-clockwise motion to said freadle when said handle bar motion is a back lateral motion; and not imparting a motion to said freadle when said handle bar motion is a forward lateral motion.

231. The device of claim 228, wherein: said handle defines a handle slot; a first end of said interconnect is at least partially received within said handle; a second end of said interconnect is affixed to said freadle; and said first end of said interconnect reciprocates within said slot in response to a motion of said handle.

232. An exercise device, comprising: a handle bar; a freadle; an upright attached to said handle bar at a first end and attached to said treadle at a second end; and an interconnect operationally attaching said handle bar to said upright, said interconnect resisting a handle bar motion.

233. The device of claim 232, further comprising a hinged joint attaching said upright to said handle bar; and wherein said interconnect comprises a shock.

234. The device of claim 232, further comprising a spring joint attaching said upright to said handle bar; and wherein said interconnect comprises a fixed-length member.

235. An exercise apparatus, comprising: a first handle bar; a protrusion extending from said first handle bar; and a first freadle slidably attached to said protrusion.

236. The exercise apparatus of claim 235, wherein: the slidable attachment between said first treadle and said second freadle comprises a slot mnning at least partially along the length ofthe freadle; and a motion of said handle bar fransfers force along said protrusion to said slot, thereby imparting a motion to said first freadle.

237. The exercise apparatus of claim 236, wherein said first handle bar is pivotally attached to a frame of said exercise apparatus.

238. The exercise apparatus of claim 237, further comprising: a second freadle pivotally attached to said frame; and an interlink affixed to said first and said second treadles, said interlink operative to move said second freadle in a direction opposite said motion of said first freadle.

239. The exercise apparatus of claim 238, wherein said interlink is Z-shaped.

240. The exercise apparatus of claim 238, wherein said interlink is C-shaped.

241. An exercise apparatus, comprising: a frame; a first handle bar; a first protrusion attached to said first handle bar; a first freadle operably attached to said frame; a first slot formed in a side of said first freadle, said slot slidably mated to said first protrusion; a second handle bar; a second protrusion attached to said second handle bar; a second treadle operably attached to said frame; a second slot formed in a side of said second freadle, said slot slidably mated to said second protrusion; wherein a first motion of said first handle bar slides said protrusion along said first slot, transferring said first motion to said treadle; and a second motion of said second handle bar slides said protrusion along said second slot, transferring said second motion to said freadle.

242. A resistive handle structure for an exercise device, comprising: a handle bar; an anchoring element; and a resistive element affixed to the handle bar at a first end and the anchoring element at a second end, the resistive element providing a resistance acting against a motion ofthe handle bar.

243. The handle sfructure of claim 242, wherein the resistive element is a piston.

244. The handle sfructure of claim 243, wherem the anchoring element comprises a treadle, and the resistive element transfers a motion ofthe handle bar to move the freadle.

245. The handle structure of claim 243 , wherein the anchoring element comprises a treadle, and a motion ofthe freadle provides increases said resistance of said resistive element.

246. A height adjustment mechanism for an exercise apparatus, comprismg: a bracket affixed to a support element of said exercise apparatus; a slot defined in said bracket; an adjustor pin at least partially held within said slot; a height adjustment mechanism operatively attached to said adjustor pin; and a freadle operatively attached to said adjustor pin.

247. The height adjustment mechanism of claim 246, further comprising: a motor; a drive belt operatively attached to said motor and said treadle; and a tensioner device for tensioning a drive belt,.

248. The height adjustment mechanism of claim 247, wherein the tensioner device comprises: a tensioner head resting on said drive belt; a spring attached to said tensioner head; and a base attached to said spring and further attached to said support element; wherein said spring exerts resistive force on said drive belt through said tensioner head, said resistive force increasing as said treadle is raised.

249. The height adjustment mechanism of claim 246, further comprising: a motor, said motor affixed to said freadle; wherein said motor raises and lowers with said treadle.

250. A freadle motion adjustment mechanism for an exercise apparatus, comprising: a throw bar; a pivot about which said throw bar pivots; a throw adjust operative to move along said throw bar; a throw pull operatively attached to said throw adjust, the throw pull operative to permit motion of said throw adjust along said throw bar; a freadle operatively attached to said throw adjust; wherein moving said throw adjust along said throw bar away from said pivot varies a throw of said treadle.

251. The freadle motion adjustment mechanism of claim 250, further comprising: an angle bar attached to said throw adjust; an angle adjust operative to move along said angle bar; wherein said angle bar forms the operative attachment between said freadle and said throw adjust; and moving said angle adjust along said angle bar varies an operating angle of said treadle.