JPH0260505A - Lawn aeration apparatus - Google Patents

Abstract

PURPOSE: To efficiently aerate a lawn by selectively controlling the front speed of a device selectively varying intervals between tooth holes. CONSTITUTION: A lawn aeration device 14 includes a frame assembly 16 and is supported for rotary movement in a lawn area by a pair of driven rubber tire rear wheels 18 and a rubber tire front steering wheel 20. The device is given power by an internal combustion engine and controlled by an operator sitting on a seat 24 positioned on the engine. Steering is executed by using a handle bar connected with the front wheel 20. An aeration device mechanism 28 positioned at the rear part of the device includes plural sets of center-cut teeth 30 and when the aeration mechanism is at a lowering position, successively driven to the ground surface to remove lawn cores at some intervals to provide an aeration effect.

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION The present invention relates generally to lawn care devices, and more particularly, to lawn maintenance devices for removing substantially cylindrical turf cores with minimal disturbance of the surrounding turf area. , relates to a device for aerating lawns by sequentially driving sets of coring teeth into the soil.

To summarize the invention, a lawn aeration device of the type comprising a plurality of vertically reciprocating toothed arms, each having one or more core teeth at a lower end for engagement with the lawn. It is. The toothed arm mechanism is driven directly from the device engine at a predetermined speed.

The device is driven onto the lawn by a hydraulic motor driven by a hydraulic pump coupled to an engine. A control arrangement is provided which allows selective control of the tooth hole spacing in the turf by controlling the pump output and thus the forward speed of the device. Pump control is automatically released by raising the toothed arm assembly to the transfer position. The vibration damping steering assembly uses a flexure disc that connects the steering handlebar to the steerable equipment wheels.

The importance of aerating a lawn to allow water, oxygen and nutrients to reach the root zone is recognized by lawn care professionals, especially those involved in maintaining functional lawn areas, such as golf courses, athletic fields, etc. has been recognized for some time. Various types of devices have been devised for aerating lawns, some simply cutting into the ground and others setting aside or removing small sections of lawn at intervals.

Lawn 1 aeration devices are basically divided into two major types, the simplest being the rotating type, generally consisting of a roller, i.e. a rotatably mounted element with a soil penetrating element. usually equipped with a disc-shaped knife, spoon tooth or hollow corer tooth. Knife-equipped roller-type aerators provide a fairly neat slining action for the lawn, whereas rotary-type devices using fixed spoon teeth or cored teeth tend to disturb and tear up the area directly surrounding the tooth holes. , so it is not suitable for critical grass surfaces such as golf course greens.

A second, more complex type of aerator is the reciprocating type, which uses hollow core teeth and is driven substantially perpendicular to the ground in a reciprocating manner. Not only do such devices not cause damage to the surrounding lawn surface, they are also typically able to achieve deeper penetration of the soil than rotary aeration devices. The present invention is directed to a reciprocating aeration device.

This type of aeration device is disclosed in U.S. Pat.
0.565.

The aeration mechanism of the device disclosed in that patent uses a return mechanism for the lower end of the toothed arm and is actuated by relative movement of the device and the toothed arm when engaged with the turf. Such type of aeration device correspondingly does not link the gear arm return drive to the device drive, and the device is correspondingly not limited to a single speed of movement in the lawn. The present invention uses this type of tooth return mechanism.

SUMMARY OF THE INVENTION The present invention provides an arrangement for adjusting tooth hole spacing in a lawn by adjusting the speed of forward movement of the device. Specifically, the toothed arm mechanism is driven directly by the device engine at a constant predetermined speed.

Forward movement of the device is provided by a hydraulic motor coupled to a hydraulic pump driven by the engine. The output of the hydraulic pump is selectively limited in the forward direction of travel by a cam adjustable from the operator's position to vary the pump output and thus the tooth spacing.

A means is provided for automatically disengaging the forward speed control upon raising the toothed arm mechanism. This arrangement includes mounting a cam-limited movement of the pump control lever in a pivot bracket, rotation of which is effected by raising the toothed arm mechanism to remove the cam from engagement by the pump control lever.

The invention further includes a vibration damping steering mechanism including a flexure disc connecting the steerable wheels of the device and the steering shaft.

It is therefore a first object of the present invention to provide a reciprocating lawn aeration device for driving sets of hollow core teeth onto the lawn one after the other, and which device provides a selective forward speed of the device. means for selectively varying the spacing of the tooth holes by selectively controlling the spacing between the teeth.

Another object of the invention is that by raising the toothing mechanism to a moving position,
It is an object of the present invention to provide a lawn aeration device as described above that automatically returns the speed control of the device to its full range.

Yet another object of the invention is to provide a lawn aeration device as described above having an improved steering mechanism to minimize steering handlebar vibration.

Additional objects and advantages of the invention will become more readily apparent from the following detailed description of the preferred embodiments.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, and with particular reference to FIGS. 1 and 2, a lawn aeration system, generally indicated at 14, in accordance with the present invention includes a frame assembly 16 and includes a pair of covers. By means of a drive rubber tire rear wheel I8 and a single pivotably mounted rubber tire front steering wheel 20,
Supported for rolling movement in grass areas. The device is powered by an internal combustion engine 22, shown schematically in FIGS. 6 and 7, and controlled by an operator seated in a seat 24 located above the engine. Steering is accomplished using a handlebar 26 connected to the front wheels 20, and appropriate foot and hand controls are provided, as described in more detail below.

The aerator mechanism 28 located at the rear of the device has core extraction teeth 3
0, which are sequentially driven onto the ground when the aeration mechanism is in the lowered position, by removing turf cores at intervals, as shown in FIGS. 9 and 12, for example. Provides aeration effect. Aeration device mechanism 28, 1988
U.S. Patent No. 4.750.56, issued June 14,
No. 5 and is therefore incorporated by reference. 6th
This mechanism, which is shown schematically in the figure, accordingly needs to be described only in general terms.

Considering the details of the device, the frame 16 includes parallel spaced side frame elements 32 (FIG. 7) connected by transverse frame elements 34, 36 and 38 (FIGS. 6 and 7). Ru. The front end of the side frame member 32 is
They are connected by a U-shaped forward seven-frame member 40 shown in FIG.

The rear drive wheels 18 are attached to an axle 42 and are provided with a differential drive 44 having a chain drive sprocket 46 . A hydraulic motor 48 mounted to one of the side frame members 32 includes a sprocket 50 connected to a differential sprocket 46 by a drive chain 52.

The motor 48 is connected by a hydraulic line 54 to a hydraulic pump 56 mounted on a pump bracket 57 and to the engine 22 by a shaft coupling 58 . The output of the pump 56 is controlled by a pump control lever 60, which is attached to a vertical pump shaft 62 and whose rotation is controlled to vary the output of the pump.

The manner in which the control lever 60 is actuated and the movement adjusted to control tooth hole spacing in the lawn will be discussed in detail below.

The aerator mechanism 28, as shown in FIGS. 6 and 7,
Attached to the aerator frame assembly 64.

Frame assembly 64 includes a pair of spaced side rails 66 and is pivotally attached at 68 to ears 70 extending rearwardly from transverse frame member 36 . The side rails 66 are connected to the vertical frame member 6 at the rear end.
8 and extending therebetween is a transverse upper aerator frame member 70 and an intermediate tubular member 72, the latter member also serving as a hydraulic fluid reservoir. The aerator frame 64 and the aerator mechanism supported by the frame are attached at the lower end to a frame element 76 attached to the transverse frame member 38 and at the upper end to the tubular seven-frame member 72. It is selectively raised and lowered using a hydraulic cylinder 74 attached to a bracket 78.

Operation of the cylinder 74 is controlled by a foot pedal 80 to the left of the operator's position, which controls a hydraulic valve 82 connected to the cylinder by a hydraulic line 84, as shown in FIG. Hydraulic line 86 delivers pressurized fluid from pressure pump 56 to valve 82 . Valve 82 includes a pressure relief valve and a drain line 88 connected to a hydraulic reservoir within frame member 72 . Hydraulic fluid flow from the hydraulic reservoir flows through hydraulic line 90 to filter 92 and thus through line 94 to pump 56 .

The aerator mechanism mounted on the pivotably arranged frame 64 includes four tine arms 96, each of which has a tine retainer 98 at its lower end.
and supports three teeth 30 in a spaced arrangement as shown in Figure 6a. The teeth 30 are arranged such that during the downward ground penetration stroke of the tooth arm, the captured turf core is released upwardly and is forced out of the top of the tooth by subsequent penetration of the core.
Made hollow and flared.

The toothed arm 96 is pivotally connected at its upper end to the aft end of a connecting rod arm 100, and the connecting rod arm 100 is pivotally connected at its forward end to a connecting rod link 102. 102 is pivotally connected to the aerator frame. A crank 104 is attached to a drive shaft 106 supported horizontally on the aerator frame.
Pivotably connected to connecting rod arm 100 at 108 .

The drive/yaft 106 is connected to the struts 118 of the aerator frame.
sprocket l at shaft 116 attached to
-114 is driven in rotation by chain sprocket 110 cooperating with chain 112 driven by -114. Shaft 116 in turn connects dual pulley assembly 12 to motor drive pulley 124 by drive bell l-122.
0 at one end. An idler 126 attached to the machine frame 36 places the belt 122 under driving tension only when the aerator frame is pivoted to the down aeration position, as shown in FIG. ” - In the raised aerator position, the bell i-
26 to allow engine drive boob 1124 to slide to automatically stop aerator mechanism movement.

The above aerator mechanism is described in U.S. Patent No. 4.750.565.
and provides an essentially elliptical movement of the upper end of the toothed arm 96 as described.

The movement of the lower end of the geared arm is controlled by a geared arm return mechanism, at the rear end to the lower end of the geared arm and at the forward end to the gear box 1 in the aerator frame 64.
32 includes a link 128 pivotally connected to a crank +30 attached to a gear shaft of 32. A toothed arm return mechanism using links and gearboxes controls the movement of the lower toothed arm end pairs, one gearbox 1 for each pair of adjacent geared arms.
There are 32. When the device moves in the m1 direction, relative backward movement of the turf-engaged toothed arm with respect to the frame results in forward movement of the linked adjacent toothed arm to the proper starting position for the ground-engaging stroke. Positioning it/November 1987
Co-pending U.S. Application No. 120.94 filed on May 16th.
More details will be given in issue 8! = This arrangement is particularly effective in freeing the gear arm return mechanism from the device wheel drive and accommodating rotational movement of the device.

The speed of operation of the toothed arm mechanism is controlled by varying the speed of the engine in the direct Bell I drive. As shown in FIGS. 1, 2 and 1O, the throttle control lever 134 is located adjacent to the operator's seat;
Allows establishment of appropriate gear arm speed. As described, the forward speed of the device at the ground is varied to provide the desired tooth spacing, while both the engine speed and the resulting speed typically require no adjustment once established. Changes in engine speed also produce changes in vehicle ground speed, but do not affect tooth spacing because gear arm speed is increased proportionately.

As is common with this type of device, the toothed arm mechanism is arranged such that the toothed arm continuously engages the teeth with the ground. The cranks 104 are mounted at 90 degree intervals on the crank shafts 1-106, and the toothed arms are correspondingly advanced sequentially towards the ground in 90 degree rotations of the crankshaft.

For actuation of the control lever 60 of the hydraulic pump 56, the free end of the control lever is connected to a control rod 138 by a ball and socket joint 136, as seen most clearly in FIG.
It is pivotably connected to lever 140 and then pivotably attached to the device frame at +42. A foot pedal 144 is pivotally attached to the frame at a central pivot axis +46 and a crank or arm 148
and by a connecting rod 150 to the lever 140 for its movement and the consequent movement of the rod 138 and pump control lever 60. As given by 1 with reference to Figures 6 and 7,
Rotation of the pedal 144 in the toe down direction causes the rod 150 to rotate.
, rearward movement of lever 140 and rod 138 and control lever 6
0 and the resulting backward movement of the free end of the pump.
This causes counterclockwise rotation of shaft 62.

Conversely, movement of the pedal 144 in the heel-inferior direction produces forward movement of the linkage and resulting forward movement of the control lever 60 and clockwise rotation of the pump shaft 62. Control lever 60 and pump shaft 62 have a neutral position in which there is no pump output and thus no flow to hydraulic motor 48 . A spring mechanism 152 is provided in association with the lever 140 and, when the pedal is released, causes the lever 140 and thus the pump control lever 60 to move to the neutral pump, similar to that shown in U.S. Pat. No. 4,352,302. Helps get you back into position. Appropriate electrical circuitry (not shown) is provided to prevent starting of the engine when pedal 144 and control lever 60 are in a position other than the neutral position.

A novel feature of the present invention is a control mechanism that allows the operator to select the spacing distance between successive footprints of teeth in the lawn.

As shown, this is accomplished by varying the speed of movement of the device across the lawn while the toothed arm mechanism speed remains constant. The mechanism for controlling the speed of the device in the lawn is shown in FIGS. 6 and 7 and includes a speed control cam 154 having a cam surface 155 that serves as a stop for movement of the control lever 60. The cam 154 is a cam
Pivotably attached at 156 to the lower end of bracket 158 , cam bracket 158 is pivotably attached to pump mounting bracket 57 at 160 . As shown in detail in Figures 8 and 11,
The cam 154 is rotated i1+11115 using a control cable 162 connected to the cam 154 at 164 at a point opposite the pivot axis 156 from the cam surface 155.
Rotated around 6. The cable 162 is attached at the opposite end to a spacing control lever +66 pivotably mounted to the equipment frame at 168 and threaded through a slot 172 in an arcuate control panel 174 adjacent the operator's position. attached part 17
has 0.

Threaded control knob 176 engages threaded portion 17 against a pair of locking nuts 178 to lock lever 166 in a desired position in slot 172.
Selectively screwed to 0. An indication is provided adjacent to the slot as shown in FIG.
indicates the tooth hole spacing provided for a given setting. As shown in FIG. 11, a pivot shaft 156;
The distance between the points on the cam surface decreases from the lower end to the upper end of the cam surface, so that the forward movement of lever 166 and the consequent downward movement of cam 154 causes control lever 60 to be restricted further rearward. position, thus producing a large pump power and a consequent increase in the speed of the hydraulic motor 48, thereby increasing the tooth spacing.

As shown in FIGS. 8 and 9, when the lever 166 is set to a 2 inch tooth spacing by the knob 176,
Cam 154 engages cam surface 155 near the lower end of the cam surface by control lever 60 applying pedal 144 to the fully depressed toe completion position, thus
It is positioned to limit the pump output to a relatively low flow rate and therefore the forward speed of the device to a low speed. Because the toothed arm mechanism operates at a constant speed that is directly proportional to engine speed, the distance S between repeating tooth hole patterns in the lawn is relatively short, in this case 2 inches.

In contrast, lever 166, as shown in FIG.
When set to the 5 inch setting, the cam 154 is rotated such that the control lever 60 engages the cam surface after a large angular control lever displacement and therefore a large flow rate from the pump. A high forward velocity produces a large spacing S', in this case 5 inches, as shown in FIG. The tooth patterns of FIGS. 9 and 12 were produced by single tooth arms, each of which supports three coring teeth, as described above.

Pressing the pedal 144 into the heel-down position moves the pump control lever 60 forward, causing a reversal of pump output flow. Because no preparation is made to adjust the tooth hole spacing,
It is not recommended that the device be operated in reverse. Reverse movement capability is primarily provided for maneuvering the device with the toothed arm mechanism retracted.

In situations where the toothed arm mechanism is retracted, the cam +
It is desirable to operate the device at forward speeds in excess of the forward speed limited by 54. Accordingly, means are provided for automatically retracting the cam when the toothed arm mechanism is raised.

This means includes a rod 180 as shown in FIGS.
At the forward end, the cam bracket L-158
A bracket 182 in the aerator frame 64 is pivotally connected to the upper end and at the aft end.
can be attached to. When the aerator mechanism is rotated to the elevated position, rod 180 moves forward, as shown in dashed lines at 180' in FIG. 158. This rotates the cam 15 from near the control leno-60.
1 and allow a full range of aft control lever movement in response to toe movement of control pedal 144. When an aeration operation is desired, the lowering of the toothing pulls the rod 180 rearwardly by capturing the double nut 406, returning the cam 154 to a position that limits rearward movement of the pump control lever 60. The double nut 406 also allows for fine tooth hole spacing.

The impact of the toothed arm by the ground produces a certain amount of vibration of the device, especially in the vertical direction. For operator comfort,
The seat 24 is equipped with a spring suspension system 18 as shown in Figure M1.
4 can be provided. Additionally, vibration damping means are provided for the steering mechanism, as described below.

3-5, the front wheels 20 of the device include a steering yoke 1 including an upwardly extending yoke 190.
It is attached at 88 by an axle 186. The yoke 188 and shaft 190 are coupled to each other by a thrust bearing 192 mounted in a cylindrical housing 194 in a frame member 196 extending from the device frame 40.
Rotatably supported.

The handlebar 26 is a handlebar extending downward.
Including Nyafu 197, Handlebar Nyafu I-19
7I, extending through column 1.98 and column 200. The rubber ring 198 is held rigidly in position on the frame element 202 welded to the frame post 206, which
It can be stored in 96. bantlebar shirt h l
The gap between 97 and the rubber ring primarily allows for lateral relative movement.

The book 200 is positioned in a frame element 204 that is similar in shape to other frame elements 202 . The frame element 204 is attached to the metal strap 402.
and 404 to the dependent arms of each frame element 202 and 204, with the aid of flexible rubber elements 400 secured to the other frame elements 202. With this structure, the No'ndorha Shirt l-197 is held by the Bunyu 200 which is aligned with the yoke shaft 190. Handlebar Nyaf l-197 has rubber element 4
00 movement causes a small amount of freedom to move axially within the rubber sole 198. The orientation of the rubber element 400 in a plane parallel to the shaft 197 but obliquely driven into the front face of the machine limits the shaft 197 to primarily lateral movement.

A vibration damping shaft joint assembly 206 couples the upper end of yoke shaft 190 with the lower end of handlebar shaft 197 in a manner that provides a positive rotational connection of the shaft while allowing some axial movement. . Shaft joint assembly 206 includes T-shaped shaft joint elements 208 and 210 that are attached to the upper end of yoke shaft 190 and the lower end of bundle bar shaft 197, respectively. Elements 208 and 210, which are identical, each include a tubular body portion 212 and a transverse T-steel portion 214 attached at one end.

Arm portion 214 includes axially and radially outwardly offset pivot arms 216 extending from each side of T-shape 214 .

As shown in FIG. 5, the coupler elements 208 and 210 are assembled using a key 218 located in a cooperating keyway in the coupler element and the shaft, and a set screw 220 located in a threaded bore in the coupling element. , respectively,
Attached to shafts 190 and 197. Disposed between shaft coupling elements 208 and 21O is a flexure disc 222, preferably made of textile reinforced rubber. 1-shaped steel portion 214 and arm 21 of the connector element
6, the disc 222 has a hole for accommodating a port 224 passing through the circumferentially adjacent disc. Arms 2+6 of each coupler element 208 and 210 are arranged in a perpendicular orientation to each other so that disk 222 flexes and absorbs vertical vibrations transmitted through the rigid shaft joint assembly. The relative rotational force of the shaft is transmitted through the disc and correspondingly the yoke 188 and the wheel 2.
0 rotates in exact accordance with the rotational movement of the handlebar 26.

To prevent injury to the operator from accidental contact with moving parts of the equipment, and to suppress foreign matter from the engine and drive elements, suitable covers should be installed on the geared arm mechanisms, engine and pump end controls, drives. Provided for the mirror and steering mechanism. Therefore, very little operating mechanism is visible in FIGS. 1 and 2, including these covers. These covers are, of course, removable to allow inspection, lubrication, and maintenance of internal components.

For operation of the device, the operator assumes a seated position in seat 24, adjacent to which are located the necessary engine and device operating controls. Conventional engine controls are not shown other than throttle 134 and adjacent choke 300. Upon starting the engine, the geared arm mechanism, in the raised position controlled by the foot pedal 80 actuating the hydraulic cylinder 74, uses the handlebar 26 to steer the steerable front wheel 20, causing the device to aerate. is driven onto a grassy area. Forward movement of the device is achieved by pedal 144.
, thereby moving the hydraulic pump control lever 60 rearward until the desired speed is achieved. Thus, the pedal 144 operates when the geared arm mechanism is raised just like the accelerator pedal in a car or truck, and the full forward range of pump output is controlled by the operator when the engine throttle is fully advanced. is available. A brake pedal 304 adjacent speed control pedal 144 operates a disc brake assembly on a sprocket 46 attached to differential 44 to stop the machine when desired.

Before reaching the lawn area to be aerated, the device is stopped and the control knob 176 is adjusted to the desired hole spacing setting. When approaching the area to be aerated, the speed of the device is
Adjusted as close as possible to the aeration rate. The pedal 80 is then actuated to lower the toothed arm mechanism to the operating position, in which case the drive bell l-122 is connected to the idler 126.
automatically activated by engagement with the At the same time, bar 18
0 rotates bracket 158, bringing cam 154 into an operating position adjacent control lever 60, as shown in FIGS. 8 and 11. The cam surface 155 thus serves as a rearward limit to rearward movement of the pump control lever 60. The operator then applies toe completion travel of foot pedal 144 until foot pedal travel is prevented by engagement of control lever 60 with cam surface 155 . The resulting velocity produces the tooth hole spacing shown in the control panel display adjacent control panel slot 172.

If the operator relieves the downward pressure on pedal 144, it will tend to return to the neutral pump position under the influence of spring mechanism 152. Complete release of the pedal correspondingly results in a return to the neutral position and a cessation of forward movement of the machine. Less than full pedal release will result in lower vehicle speeds and closer hole spacing if desired for a particular area of the lawn.

Upon completion of the aeration function, the pedal 80 is actuated again;
The toothed arm mechanism is then raised to a travel position in which belt 122 is disengaged from idler 126 and becomes inactive. At the same time, rod 180 displaces cam 154 from pump control lever 60 and full pump power is obtained in the forward direction of device travel. At any point in time, the device movement is performed by pressing the pedal 14 in the downward direction.
4, but as mentioned above this is not recommended for aeration, and if aeration is attempted in this direction, no provision is made to reversely manage the rate. It won't happen.

Obviously, changes in construction details may be made by those skilled in the art without departing from the spirit and scope of the invention.

The main features and aspects of the invention are as follows.

(i) a frame, means for supporting the frame for rolling movement in a lawn area and comprising at least one drive wheel; means for driving the drive wheel in rotation; and a plurality of toothed arms. an aerator mechanism attached to the frame, each toothed arm having at least one downwardly directed lawn corer tooth disposed at a lower end and driving the tooth into the lawn; an aerator drive means for continuously moving the toothed arm;
and control means for selectively varying the speed of the means for driving the drive wheel, thereby varying the spacing of the tooth holes in the lawn.

2. a frame and means for supporting the frame for rolling movement in a lawn area and comprising at least one drive wheel; means for driving the drive wheel in rotation; an internal combustion engine; means comprising a hydraulic pump coupled to the engine; a hydraulic motor coupled to the hydraulic pump; and an aerator mechanism mounted to the frame comprising a plurality of toothed arms, each toothed arm comprising: an aerator mechanism having at least one downwardly directed lawn corer tooth disposed at a lower end and an aerator drive means for continuously moving the toothed arm to drive the tooth into the lawn; an aerator drive means driven by the internal combustion engine at a speed commensurate with the engine speed, and the output of the hydraulic pump and thereby selectively varying the speed of movement of the device in the lawn, thereby causing teeth to be removed in the lawn. and control means for varying hole spacing.

3. The aerator mechanism is selectively raised from an operating position to an elevated transfer position, and comprising means for automatically releasing the control means when the aerator mechanism is raised to the elevated position. The invention described in 2 above.

4. a frame and means for supporting the frame for rolling movement in a lawn area and comprising at least one drive wheel; means for driving the drive wheel in rotation; an internal combustion engine; means comprising a hydraulic pump coupled to the engine; a hydraulic motor coupled to the hydraulic pump; and an aerator mechanism mounted to the frame comprising a plurality of toothed arms, each toothed arm comprising: an aerator mechanism having at least one downwardly directed lawn corer tooth disposed at a lower end; an upper end of the toothed arm for continuously driving the toothed arm in reciprocating motion onto the lawn; an aerator drive means coupled to an aerator drive means driven by the internal combustion engine at a speed commensurate with the engine speed, and for each ground penetration stroke to return the lower end of the toothed arm to a forward position; toothed arm return means for the toothed arm, comprising motion transmission means connected to a lower portion of each of the toothed arms;
When released from the turf, it produces a forward movement with respect to the lower end of one of the toothed arms, and during the forward movement of the frame in the turf, the engagement of the latter toothed arm with the turf causes a forward movement. a toothed arm return mechanism that balances the rearward movement of another lower end of the toothed arm with respect to the frame, selectively varying the output of the hydraulic pump and thus the speed of movement of the device in the lawn, thereby and control means for varying the spacing of the tooth holes.

5. The aerator mechanism is selectively raised from an operating position to an elevated transfer position, and comprising means for automatically releasing the control means when the aerator mechanism is raised to the elevated position. The invention described in 4 above.

6. said control means selectively varying the position of said cam with a cam disposed adjacent to said pump control lever to serve as a limit on said control lever movement, thereby permitting movement of said control lever; 5. The invention as claimed in claim 4, comprising means for varying the range and therefore the speed of the device.

7. The means for selectively changing the position of the cam,
7. The invention according to 6 above, further comprising a control lever attached to the operator's position.

8. The invention according to claim 6, wherein the pump control lever is actuated by a foot pedal adjacent to the operator's position in the 7th frame.

9. A vibration-damping shaft joint for connecting a steering yoke of a three-wheeled vehicle to a steering wheel/steering wheel, comprising: a first T-shaped shaft joint element attached to the steering yoke; and a first T-shaped shaft joint element attached to the steering yoke; and the steering handle in a reversed configuration. the second attached to
a flexural coupler disk disposed between the first and second T-shaped elements closest to the transverse arms; transverse arms of the T-shaped elements disposed in perpendicular relationship to each other; and the disk. and means for attaching a transverse arm of the T-shaped element to the disc adjacent the periphery of the vibration damping shaft joint.

10. A vibration damping shaft joint for coupling a steering yoke of a three-wheeled vehicle to a steering wheel/handle, the steering yoke comprising an upwardly extending steering wheel journalled radially and axially to the vehicle frame. the steering wheel has a shaft;
a downwardly extending shaft aligned with the yoke shaft, the nodle shaft being journalled radially by the frame but slidable axially and in a vibration damping shaft joint terminating at a lower end in spaced relation to an upper end, a first shaft joint element at the upper end of the yoke shaft, the shaft extending perpendicularly to the yoke shaft; a first shaft joint element including a joint arm; a second shaft joint element at a lower end of the handle shaft, the second shaft joint element comprising a shaft joint arm extending perpendicularly to the handle shaft; a flexure coupler disk disposed between the first and second shaft joint elements proximate the transverse arm; a vibration damping shaft joint comprising means for attaching an arm, the attachment points of the arm being angularly spaced on the disc.

11. The invention as set forth in 10 above, wherein each said shaft joint element includes a pair of opposed radially extending arms.

12. The invention according to 11 above, wherein the attachment points of the arms of the disc are arranged at 90 degree intervals.

13. The above-mentioned lO, wherein the disc is formed from textile reinforced rubber.
The invention described in .

[Brief explanation of the drawing]

FIG. 1 is a right front view of the lawn aeration device according to the invention. 2 is a plan view of the apparatus shown in FIG. 1; FIG. FIG. 3 is an enlarged partial right front view of the apparatus of FIGS. 1 and 2, shown partially in section to show details of the steering mechanism of the apparatus; FIG. Figure vg4 is an enlarged exploded perspective view showing vibration damping components of the steering mechanism. FIG. 5 is a view taken along line 5--5 of FIG. FIG. 6 is an enlarged schematic right side front view of the device highlighting details of the control mechanism of the hydraulic wheel drive; Figure 6a shows the arrangement of core teeth in each tooth arm.
Figure 6 is a view taken along figure line 6a-6a; FIG. 7 is an enlarged schematic partial plan view of the apparatus showing the aeration mechanism drive, the control system for the hydraulic wheel drive, and the hydraulic system; FIG. 8 is an enlarged side view separating details of the tooth spacing control linkage. FIG. 9 is a plan view showing the tooth hole spacing in the lawn achieved by the control settings in the position shown in FIG. 8; FIG. 1O is a view taken along line 1O-1o of FIG. FIG. 811 is a diagram similar to FIG. 8 showing interval control in different settings. FIG. 12 is a diagram similar to FIG. 9 showing the tooth spacing due to the controlled control in the position of FIG. 11; 14... Lawn aerator 16... Frame assembly 18... Rear wheel 20... Front wheel 26... Handlebar 28... Aerator mechanism 30... Coring tooth 48... Motor 60... Control lever 64... Frame assembly 96... Gear arm patent applicant Outboard Marine Corporation

Claims (1)

[Claims] 1. A frame, means for supporting the frame for rolling movement in a lawn area and having at least one drive wheel, means for rotationally driving the drive wheel, and a plurality of teeth. an aerator mechanism attached to the frame having arms, each toothed arm having at least one downwardly directed lawn corer tooth disposed at a lower end; selectively varying the speed of the aerator drive means for sequentially moving the toothed arms and the speed of the means for driving the drive wheels, thereby varying the spacing of the tooth holes in the lawn; A lawn aeration device characterized by comprising: control means for causing the lawn aeration to occur. 2. a frame, means for supporting the frame for rolling movement in a lawn area and having at least one drive wheel, means for rotationally driving the drive wheel, an internal combustion engine, and coupled to the internal combustion engine; a hydraulic pump, the means for rotationally driving the drive wheel comprising a hydraulic motor connected to the hydraulic pump, and further mounted on the frame having a plurality of toothed arms. an aerator mechanism, each toothed arm having at least one downwardly directed lawn corer tooth disposed at a lower end; an aerator drive means for sequentially moving the aerator, the aerator drive means being driven by the internal combustion engine at a speed commensurate with the engine speed; and control means for varying the spacing of the tooth holes in the lawn. 3. a frame, means for supporting the frame for rolling movement in a lawn area and comprising at least one drive wheel, means for rotationally driving the drive wheel, an internal combustion engine, and coupled to the internal combustion engine; a hydraulic pump, the means for rotationally driving the drive wheel comprising a hydraulic motor connected to the hydraulic pump, and further mounted on the frame having a plurality of toothed arms. an aerator mechanism, each said toothed arm having at least one downwardly directed lawn corer tooth disposed at a lower end; an aerator drive means connected to the upper end of the toothed arm, the aerator drive means being driven by the internal combustion engine at a speed commensurate with the engine speed; toothed arm return means for returning the lower ends of the arms to a forward position, including motion transmission means connected to the lower portion of each of the toothed arms, when released from the turf, one of the toothed arms; teeth producing a forward movement with respect to the frame at the lower end, which is balanced by a rearward movement of another lower end of the toothed arm with respect to the frame carried out by engagement with the turf during the forward movement of the frame in the turf; arm return mechanism;
A lawn aeration device, characterized in that it comprises control means for selectively varying the output of the hydraulic pump and thus the speed of movement of the device across the lawn, thereby varying the spacing of the tooth holes in the lawn. 4. A vibration damping shaft joint for connecting a steering yoke of a three-wheeled vehicle to a steering handle, comprising: a first T-shaped shaft joint element attached to the steering yoke; and a first T-shaped shaft joint element attached to the steering handle in a reversed configuration. second
a flexible coupler disk disposed between the first and second T-shaped elements proximate the transverse arms, the transverse arms of the T-shaped elements disposed in perpendicular relationship to each other; and further comprising means for attaching a transverse arm of the T-shaped element to the disc adjacent the periphery of the disc. 5. A vibration damping shaft joint for coupling a steering yoke of a three-wheeled vehicle to a steering handle, wherein the steering yoke is connected to an upwardly extending steering shaft that is journal-supported in the vehicle frame in the radial and axial directions. The steering wheel has a
a downwardly extending shaft aligned with the yoke shaft, the handle shaft journalled radially by the frame but axially slidable relative to the frame; a vibration damping shaft joint terminating at a lower end in spaced relation to the upper end of the yoke shaft, a first shaft joint element at the upper end of the yoke shaft and perpendicular to the yoke shaft; a first shaft joint element including a shaft joint arm extending from the handle shaft; and a second shaft joint element at the lower end of the handle shaft, the second shaft joint element comprising a shaft joint arm extending perpendicularly to the handle shaft. a flexible coupler disc disposed between the first and second shaft joint elements proximate the transverse arm; and a flexible coupler disk disposed between the first and second shaft joint elements proximate the transverse arm; means for attaching the transverse arms of the coupling element, the attachment points of the arms comprising:
and means angularly spaced in the disc.