US3826480A

US3826480A - Multi-functional frictional-resistance apparatus

Info

Publication number: US3826480A
Application number: US00368598A
Authority: US
Inventors: R Johnson; R Goodrich
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-08-16
Filing date: 1973-06-11
Publication date: 1974-07-30
Anticipated expiration: 1991-07-30

Abstract

An adjustable energy absorbing device having, among many other uses, that as an exercise device. An elongated housing, closed at one end, contains a slidable member reciprocably movable in and out of the opposite end of the housing. Frictionally encircling the member is a flexible element one end of which is fixed with respect to the housing and the other end of which may be pulled or released to vary the degree of frictional gripping of the member by the element by means operatively associated with the housing. When the device is to be employed in exercising the human body, a pad and strap assembly may be disposed on the closed end of the housing and the outer end of the reciprocable member, thereby to adapt it to be secured between the legs of the user. The device can also be employed to attenuate the effects of shocks or impacts which might be encountered in the operation of an automotive vehicle.

Description

United States Patent 1 91 Johnson et a1.

1111 3,826,480 1 July 30, 1974 MULTl-FUNCTTONAL FRICTIONAL-RESISTANCE APPARATUS [76] Inventors: Richard W. Johnson, 900 King St.,

Arbuckle, Calif. 95912; Robert S. Goodrich, 137 Sierra St., El Segundo, Calif. 90245 22 Filed: Junell, 1913 121 App]. No.: 368,598

Related U.S. Application Data [63] Continuation-impart of Ser. No. 172,029, Aug. 16,

1971, abandoned.

[52] U.S. Cl. 267/9 B, 188/129, 272/79 A, 272/80, 280/124 R [51] Int. Cl A63b 21/12, B60g 17/06, Fl6f 7/08 [58] Field of Search 272/79 A, 79 D, 79 R, 67, 272/68, DIG. 3, DIG. 4, D16. 6, 80, 57 R, 82, 83 R, 83 A; 267/9 R, 9 B; 188/654, 65.5,

[ 56] References Cited UNITED STATES PATENTS 695,508 3/1902 Truffault 2617/) R 2,106,994 2/1938 Chapman 272/79 X 3,107,906 10/1963 Maier 3,174,343 3/1965 Kasulis 272/80 X 3,197,204 7/1965 Holkesvick et a1. 272/79 A 3,227,447 1/1966 Baker cl a1 272/79 R 3,332,523 7/1967 Chambers 267/9 B X 3,411,776 11/1968 Holkesvick ct a1. 272/79 A 3,498,608 3/1970 Krug 272/79 R 3,510,132 5/1970 Holkesvick 272/80 x 3,603,433 9/1971 Keathley et a1 188/129 x 3,608,900 9/1971 Welch 272/79 A FOREIGN PATENTS OR APPLICATIONS 351,462 5/1905 France 272/68 Primary ExaminerAnton O. Oechsle Assistant Examiner-Arnold, W. Kramer Attorney, Agent, or Firm-Smyth, Roston & Pavitt [5 7 ABSTRACT An adjustable energy absorbing device having, among many other uses, that as an exercise device. An elongated housing, closed at one end, contains a slidable member reciprocably movable in and out of the opposite end of the housing. Frictionally encircling the member is a flexible element one end of which is fixed with respect to the housing and the other end of which may be pulled or released to vary the degree of frictional gripping of the member by the element by means operatively associated with the housing. When 'the device is to be employed in exercising the human body, a pad and strap assembly may be disposed on the closed end of the housing and the outer end of the reciprocable member, thereby to adapt it to be secured between the legs of the user.

The device can also be employed to attenuate the effects of shocks or impacts which might be encountered in the operation of an automotive vehicle.

10 Claims, 12 Drawing Figures PAIENTEDmaomu SHEEF 1 BF 3 iawzsn/wwaznarfl MULTI-FUNCTIONAL FRICTIONAL-RESISTANCE APPARATUS This is a continuation-in-part of application Ser. No. 172,029 filed Aug. 16, 1971, and now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates broadly to mechanisms for absorbing energy in the form of a force applied in a predetermined direction and, as such, could be employed to attenuate the effect of a collision between two oppositely moving bodies or a moving body and a permanent object or station. The invention, however, also has particular application to an exercise device for isotonic exercises wherein the amount of force required to utilize the device may be selectively varied.

2. Description of the Prior Art There have been developed a myriad of prior exercise devices having a wide range of capabilities, function and constructional details. Many of the newer developed devices are utilized for isometric exercises wherein the devices are adjusted such that the user will exert a constant force against a portion of the exercise device. In these types of devices, there is no movement, generally, of a portion of the device during exercise. The user merely works against or exerts force against a portion of the device which resists the efforts of the user to move it. In exercisers wherein a portion thereof moves in accord with energy expended by the user, such devices have often incorporated some type of spring tension or spring force.

Among the disadvantages of such devices is the fact that they are not arranged so that the amount of force to be expended to move a portion of the exercise device can be readily and critically adjusted. Further, where a spring is utilized, the amount of force required to move the device in one direction differs substantially from the amount of force required to move it back in the opposite direction. In fact, in such spring type devices, force is normally expended in moving the device only in one direction, namely, against the action of the spring with either compressed or exanded spring reacting in the opposite direction to return the device to its at rest state. Another disadvantage of any type of spring loaded exercise device, is that the spring or springs therein tend to lose their strength and even break upon repeated and continuous usage. Examples of such prior art devices are illustrated and described in the following patents:

Were one to eliminate springs from an exercise device by providing a hydraulic or pneumatic mechanism, he might well obviate the problem of unidirectional force mentioned hereinabove, but the. device could would require careful machining and scaling in order that it would operate well and not leak any of its fluid,

thereby rendering it expensive to produce. If pneumatic, it would also require precision machining and sealing to avoid air or other gas leakage, and provision would have to be made for replenishing its air or gas fluid. In addition, if both types of devices were made adjustable to vary the force required to operate them, they could well be considerably more expensive to produce than a person might care to pay for a mere exercise device.

The above description of prior art type of devices has pertained mostly to exercisers that are gripped by the user to increase muscular activity in portions of the body above the waist, particularly the anns, chest and the like. One area of the body for which there has not been previously developed a successful exercise device or apparatus, has been the muscles that run along the inner and outer portions of the legs. The strengthening of such muscles can serve to limit the amount of injury that can be incurred by athletes, such as skiers, track mean and any of the types of ball players, which are normally susceptible to various leg injuries. Thus, it is particularly desirable to provide an exercise device which can be readily used to so strengthen the leg muscles in the aforegoing areas.

SUMMARY OF THE INVENTION The present invention avoids the problems encountered with the prior art devices. In its preferred embodiment, it may be comprised of a housing which is preferably tubular and is closed at one end. Its other end may be closed by a rotatable cap having an axially extending flange which fits over the open end of the tubular body. Within the housing is a fixedly secured orificed plate dispersed transversely to the tubular housing axis. A cylindrical member which may be termed an axle, is provided to extend in from beyond the cap and into the housing through the cap and orificed plate. Detachably secured to an outer end of the axle is a handle or other means for gripping the free end of the axle by a user of the device. A flexible element such as a rope is wound about the axle within the housing. One end of the rope may be secured to a portion of the rotatable cap and the other end thereof secured to the fixed plate within the housing. Thus, any rotation of cap relative to the housing will effect a tightening or loosening of the rope about the axle to vary the amount of force required to slide the axle through its rope winding and in or out of the housing.

The closed end of the housing may also be provided with a handle or a gripping means similar to that at the outer end of the axle. The user may thus grip the handles at each end of the housing and move them relative to each other, and by pre-setting the cap, may vary the amount of force required to be expended to accomplish such movement.

The device may additionally be provided with two separate pad means which may be secured at opposite ends of the housing either as substitutes for, or in addition to, the handles or other gripping means. Desirably the pad means may be provided with straps so that they may be secured between the knees of the user. Thereby the exercise device may be so disposed between the knees of the user who may then exert force in moving his knees relative to each other to strengthen the medial and lateral muscles of the thigh and leg. Other means may be further'secured to either of both ends of the exercise device in place of, or in addition to, the removable gripping means in order that other forms of exercises can be undertaken with the device.

While the invention is thus particularly adapted for an embodiment which comprises an exerciser, as an energy absorbing device, it may also be readily adapted for use as a shock absorber for an automobile or other impact attenuating elements. I

The invention will be further understood from the following detailed description and drawings in which:

FIG. 1 pictorially shows a user of the device having the exerciser between his hands.

FIG. 2 is a cross-sectional perspective view of the exercise device of this invention.

FIG. 3 is an enlarged detailed view of the controlled end of the device of this invention.

FIG. 4 is a cross-sectional view taken along line 4--4 of FIG. 3.

FIG. 5 is a cross-sectional view of the exercise device of this invention having knee pads secured thereto and mounted on the knees of a user.

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 5.

FIG. 7 is a pictorial representation of the device of FIG. 5 mounted between the knees of a user.

FIG. 8 is a pictorial representation of the user of the device of this invention wherein it is mounted below the feet of the user to be pulled and pushed alternately.

FIG. 9 is a perspective view, partly in phantom, of a shock absorber mounting in the front end of an automobile, illustrating the use of an embodiment of the invention in such an application.

FIG. 10 is a section taken on the line 10-10 of FIG. 9.

FIG. 11 is a schematic plan view of the front end of an automobile in which an embodiment of the invention is employed to attenuate the effect of an impact upon the car bumper; and

FIG. 12 is an enlarged detail of one of the shock attenuating combinations of FIG. 11 compressed upon impact.

Referring to FIGS. 14, there is seen the exercise device 1 1 of this invention which, as shown in FIG. 1, may be disposed and gripped between the hands 13 of an individual 12. The device 11 has a preferably tubular housing 14. One end 15 of the tubular housing 14 is closed by a rotatable cap 17. The cap 17 includes a flanged portion 19 which fits 'over the end 15 of the tubular housing 14, and is rotatable thereabout. The cap 17 is further provided with a centrally orificed transverse wall portion 21.

The housing 14 has a circumferential recess 23 formed thereabout which is coalignable with a set screw 25 provided in the flanged portion 19 of the cap 17. The set screw 25 may be adjusted so that it is seated within the groove 23 to prevent the axial movement of the cap 17 relative to the housing 14. Further, an O- ring seal, 27, may be provided to be seated within an annular groove 19a on the inner wall of the flanged portion 19 of the cap 17. The seal 27 serves to supply friction between the cap 17 and end 15 of the housing 14 to prevent the cap 17 from rotatably slipping when set in a desired fixed angular position relative to the housing end 15. Disposed within the housing 14 adjacent the end 15 is a fixedly secured centrally orificed press-fitted plate 29.

Extending through the orifices 21a, 29a, in the transverse wall 21 of the cap 17 and fixed plate 29 respectively, coaxially with the tubular housing 14 is a cylindrical element or axle 31 having an outer exposed end 33 and an inner end 35 within the housing 14. The axle 33 is surrounded by a first bearing 36, which can be comprised of a plastic low friction material such as nylon, disposed in the orifice 21a in the transverse wall 21 of the cap element 17, and a like bearing surface 37 is disposed in the orifice 29a in the fixed plate 29. A handle 39 may be threadedly secured to the end 33 of the axle 31. The transverse wall 21 of the cap 17 is provided with a recess 41. Seated in the recess 41 is a knotted end 43 of a flexible element, such as a rope 45. A cross-fitted plate 42 may be used to close the outer surface of the recess 41. The rope 45 is wound preferably at least one turn about the axle 31. After being wrapped about the axle 31, the rope 45 passes through an orifice 47 provided in the fixed plate 29 and terminates in a second knotted end 49 within the housing, on the side of the plate 29 opposite from the cap end 15. Thus, the ends of the

rope

43 and 49 are secured relative to each other by the recess 41 in the wall 21 and orifice 47 in the fixed plate 29. As a result of the foregoing arrangement, any rotation of the cap 17 relative to the housing 14 will cause either a tightening or loosening of the rope wound about the axle 31, depending upon the direction of rotation of the cap. As shown in FIG. 4, and as depicted in the drawings, when the cap 17 is rotated in the direction of the arrow of FIG. 4, the rope 45 will be tightened on the axle 31, thereby to increase the restraint on any of the axle 31 through the rope turn or turns about the axle 31. Opposite rotation of the cap 17 will lessen the tightening effect of the wound rope on the axle and facilitate its movement through the rope turns. The cap 17, may be rotated so that the rope 45 is tightened to the point where the axle 31 will be almost completely prevented from any axial movement. Rotational movement of the cap 17 thus can increase or decrease the amount of force required to be expended in moving the axle 31 relative to the housing.

The end 35 of the axle 31 within the housing 14 has a peripheral groove 51 formed adjacent thereto with a lock washer 53 seated in the groove. The washer 53 serves to prevent the axle from being pulled out of the housing through the orifice 29a in the plate 29.

The opposite end 55 of the housing tube 14 may be closed by another cap 57, which threadedly engages the tube end. A handle means 59 may be integrally formed with the cap 57. Thus, the handle 59 can be readily detached by unscrewing it from the end 55 of the housing 14. Preferably, a cushion or pad 60 of felt, rubber or other material is mounted on the inner face of the cap 57, coaligned with the end 35 of the axle 31 in order to absorb any shock or energy, should the axle end35 contact the inner face of the cap 57.

Thus, to use the device described as shown in FIG. 1, an individual 12 will grip one of the opposite handles 39 and 59 thereof in each hand and will move the handles relative to each other, backward and forward as shown by the arrows in FIG. 1. The amount of energy required to so move the handles is a direct function of the degree of tightening of the rope about the axle 31 and is easily regulated by turning the cap 17. The energy required to pull the two handles apart from each other is the same as that required to push them toward each other. Thus, the user will greatly benefit from using his muscles to accomplish movement of the device in opposite directions.

FIGS. 5 and 7 illustrate an embodiment of this invention wherein the device 11 is shown mounted between

legs

61 and 63 respectively of a user. In order to so mount the device 11, a first plate 65 having a cushion or pad 67 thereon is threadedly connected by way of a collar 69 to a threaded end 55 of the housing 14, in lieu of the handle 59 of the FIGS. 1-4 embodiment described hereinabove. Two straps 71 may be adjusted on either side of the knee 75 of a user, as seen in FIG. 7, so that the pad portion 67 is immediately adjacent the inner side of the knee. The same arrangement of a pad and straps may be provided at the opposide end of the device, wherein the handle 39 has been unscrewed from the threaded outer end of the axle 31, and a threaded collar 77, having a plate 79 and associated pad 81, is substituted for the handle 39 by being threaded onto the end of the axle 31. Straps 83 may be secured about the opposite knee 85 of the user so that the device overall will span between the knees of the user in the manner shown in FIG. 7. The individual will then move his knees toward each other and away from each other while maintaining the feet in a fixed position. This form of exercise builds up the muscles on the inner portion 87 of the legs. The advantage of this lies in the fact that exercise devices do not presently exist which would enable one to so develop these important muscles.

FIG. 8 depicts an additional embodiment of this invention, wherein the knob handle 39 of the device 11 has been removed from the axle 31 and a flat plate 89 secured thereto. A user can then place his feet 91 on top of the plate to secure it onto a surface 93 and bend over and pull upwardly on handle 59 of the device and alternatively push downwardly on it. This strengthens the muscles, particularly in the back of the user.

It should be apparent that the device may comprise slidable axles at each end thereof with corresponding means as disclosed herein, to separately control the force required to move each axle. If the axles were disposed along the same axis they would each comprise one-half the length of the housing. Alternatively, the axles could be disposed on different parallel axes and thus each could extend the entire length of the housing.

Additionally, it should be pointed out that the exercise device of the present inention may be readily adapted to exercise different muscles of the body. For example, a single pad similar to or the same as that used for the knee attachment could be affixed to one end thereof. Such a pad could then be secured to the arm adjacent the inner portion of the elbow at the bicep. The user would then grip the opposite knob end and bend his arm or wrist toward and away from the bicep, the amount of force being determined by the setting of the device. Various other attachments could be affixed to the ends of the device to enable it to be attached to differing portions of the body.

In the present embodiments of the present invention which are illustrated in FIGS. 9-12 inclusive, the energy absorbing capability of the inventive concept is employed to attenuate the effects of shocks or impacts which might be encountered in the operation of an automotive vehicle. Thus, in FIG. 9, a device 11, which is essentially similar in construction to cylindrical housing-axle portion of the exerciser device of FIGS. l-4, is disposed as a shock-absorber in parallel with the coil spring 95 associated with one wheel 97 of the vehicle. In FIGS. 11 and 12, a similar portion 11" of the FIGS. 11-4 device is shown inserted with a coil spring 95 between a car bumper 99 and the car frame 101. In both of these further illustrated embodiments of the invention, the restraining effect of the flexible element or rope 45 on the axial movement of the axle 31' or 31" within the tubular housing 14' or 14" respectively is utilized to provide further attenuation of a large shock or impact upon the car wheel or bumper respectively. Return of the

axle

31 or 31" to an at rest or neutral position may be effected by the

coil spring

95 or 95 which is closely associated with the tubular device 11' or 11" respectively of the present invention. Depending upon the quantum of shock or impact which is anticipated and is to be attenuated, the

cap

17 or 17" of the device may be adjusted to provide greater or lesser tightening of the flexible element about the axle 31' or 31".

The essence of the present invention, thus, although particularly suited for an exercise device, may be seen to have other uses as an energy absorbing device.

We claim:

1. An adjustable energy absorbing device, said device being adapted to brake movement caused by force applied in a predetermined direction to one end of the device when the other end of the device is placed against an object which resists movement by such force, said device comprising:

a. an elongated housing, said housing having a longitudinal axis extending substantially in said predetermined direction, said housing being closed at one of its ends and having an opening at its other end;

b. an elongated member having an arcuate cross sectional circumference less than the inside diameter of said housing and configured to move within said housing in said predetermined direction, said member being slidably and substantially coaxially mounted to extend through said opening at the other end of the housing for telescoping movement within and relative to said housing;

c. a flexible element helically and frictionally encircling an axial segment of said elongated member, which segment reciprocates within said housing, one end of said element being fixedly secured in relation to said housing; and

(1. element tension adjusting means secured to the other end of said flexible element, said tension adjusting means being operatively disposed in association with the housing to vary the tension of said element about said member, whereby the frictional resistance which is applied to said elongated member by said flexible element about the arcuate circumference thereof may be varied by operating said tension adjusting means to tighten or loosen the helix of said flexible element about said axial segment of the elongated member.

2. An adjustable energy absorbing device, said device being adapted to brake reciprocal movement caused by force applied in opposite predetermined directions to one end of the device when the other end of the device is placed against an object which resists movement by such force, said device comprising:

a. an elongated housing,-said housing having a longitudinal axis extending substantially in said predetermined directions, said housing being closed at one of its ends and having an opening at its other end;

. an elongated member having an arcuate cross sectional circumference less than the inside diameter of said housing and configured to reciprocate within said housing in said predetermined directions, said member being slidably and substantially coaxially mounted to extend through said opening at the other end of the housing for reciprocating and telescoping movement within and relative to said housing;

c. a flexible element helically and frictionally encircling an axial segment of said elongated member, which segment reciprocates within said housing, one end of said element being fixedly secured in relation to said housing;

d. element tension adjusting means secured to the other end of said flexible element, said tension adjusting means being operatively disposed in association with the housing to vary the tension of said element about said member, whereby the frictional resistance which is applied to said elongated member by said flexible element about the arcuate circumference thereof may be varied by operating said tension adjusting means to tighten or loosen the helix of said flexible element about said axial segment of the elongated member.

parallel to the longitudinal axis of the housing;

a rope wrapped around a portion of said axle within tudinal axis of the housing; and knob means rotatably mounted on said housing, the other end of said rope being attached to said knob means,

whereby the force required to draw said axle out of said housing is controlled by rotatably posit i9 ning said knob means to change the tightness of wrap of said rope around the axle. 5. The device of claim 4 wherein said means for securing one end of the rope within the housing comprises a plate fixedly attached to said housing, said one end of the rope being retained by said plate, said plate having an opening formed therein through which the axle passes.

6. The device of claim 4, and further including means for holding said knob means in a preselected rotatable position on said housing comprising an O-ring mounted between the housing and the knob means to provide frictional engagement therebetween and a set screw mounted in said knob means for engagement with said housing.

7. The device of claim 4, and further including a handle attached to the end of the axle extending through said one of the housing and a handle attached to the other end of the housing.

8. The device of claim 4, and further including means for attaching the opposite ends of the device to the knees of a user comprising a pad attached to the end of the axle extending through said one end of the housing and a pad attached to the other end of the housing and first and second strap means attached to the housing and the end of the axle respectively for securing each of said pads adjacent to a separate one of the users knees.

9. The device of claim 4, and further including a flat plate secured to the end of the axle extending through said one end of the housing and a handle attached to the other end of the housing whereby a user exercises by standing on the plate and alternately pulls upwardly and pushes downwardly on said handle.

10. The device of claim 4 and further including means for holding said knob means in a preselected rotatable position on said housing.

Claims

1. An adjustable energy absorbing device, said device being adapted to brake movement caused by force applied in a predetermined direction to one end of the device when the other end of the device is placed against an object which resists movement by such force, said device comprising: a. an elongated housing, said housing having a longitudinal axis extending substantially in said predetermined direction, said housing being closed at one of its ends and having an opening at its other end; b. an elongated member having an arcuate cross sectional circumference less than the inside diameter of said housing and configured to move within said housing in said predetermined direction, said member being slidably and substantially coaxially mounted to extend through said opening at the other end of the housing for telescoping movement within and relative to said housing; c. a flexible element helically and frictionally encircling an axial segment of said elongated member, which segment reciprocates within said housing, one end of said element being fixedly secured in relation to said housing; and d. element tension adjusting means secured to the other end of said flexible element, said tension adjusting means being operatively disposed in association with the housing to vary the tension of said element about said member, whereby the frictional resistance which is applied to said elongated member by said flexible element about the arcuate circumference thereof may be varied by operating said tension adjusting means to tighten or loosen the helix of said flexible element about said axial segment of the elongated member.

2. An adjustable energy absorbing device, said device being adapted to brake reciprocal movement caused by force applied in opposite predetermined directions to one end of the device when the other end of the device is placed against an object which resists movement by such force, said device comprising: a. an elongated housing, said housing having a longitudinal axis extending substantially in said predetermined directions, said housing being closed at one of its ends and having an opening at its other end; b. an elongated member having an arcuate cross sectional circumference less than the inside diameter of said housing and configured to reciprocate within said housing in said predetermined directions, said member being slidably and substantially coaxially mounted to extend through said opening at the other end of the housing for reciprocating and telescoping movement within and relative to said housing; c. a flexible element helically and frictionally encircling an axial segment of said elongated member, which segment reciprocates within said housing, one end of said element being fixedly secured in relation to said housing; d. element tension adjusting means secured to the other end of said flexible element, said tension adjusting means being operatively disposed in association with the housing to vary the tension of said element about said member, whereby the frictional resistance which is applied to said elongated member by said flexible element about the arcuate circumference thereof may be varied by operating said tension adjusting means to tighten or loosen the helix of said flexible element about said axial segment of the elongated member.

3. The combination of a device as described in claim 2 with a juxtaposed parallelly disposed spring element developing suffiCient force upon compression or extension to overcome the resistance applied by the flexible element to the elongated member in said energy absorbing device of claim 2, thereby to return said member to its original position when the spring is at rest.

4. An exerciser device comprising: an elongated housing; an axle slidably mounted in said housing with one end thereof extending through one end of the housing, the longitudinal axis of said axle being substantially parallel to the longitudinal axis of the housing; a rope wrapped around a portion of said axle within said housing; means for securing one end of said rope within said housing in a fixed angular position about the longitudinal axis of the housing; and KNOB MEANS ROTATABLY MOUNTED ON SAID HOUSING, THE OTHER END OF SAID ROPE BEING ATTACHED TO SAID KNOB MEANS, WHEREBY THE FORCE REQUIRED TO DRAW SAID AXLE OUT OF SAID HOUSING IS CONTROLLED BY ROTATABLY POSITIONING SA KNOB MEANS TO CHANGE THE TIGHTNESS OF WRAP OF SAID ROPE AROUND THE AXLE.

5. The device of claim 4 wherein said means for securing one end of the rope within the housing comprises a plate fixedly attached to said housing, said one end of the rope being retained by said plate, said plate having an opening formed therein through which the axle passes.

8. The device of claim 4, and further including means for attaching the opposite ends of the device to the knees of a user comprising a pad attached to the end of the axle extending through said one end of the housing and a pad attached to the other end of the housing and first and second strap means attached to the housing and the end of the axle respectively for securing each of said pads adjacent to a separate one of the user''s knees.