AU2980501A - Implement attachment for small tractors - Google Patents

Description

1 "IMPLEMENT ATTACHMENT FOR SMALL TRACTORS" This invention relates to implement attachment means for light tractors and ride-on mowers and the like, hereinafter referred to collectively as light tractors.

Many owners of light tractors fit implements such as tilling implements and dozer blades to their light tractors.

Such implements may be fitted either in front of or at the rear of light tractors. Generally such tractors are not '"provided with a power take-off or hydraulic auxiliary drive 1 0 or theTlike and thus all implements are adapted to be manually lifted into position on and from the light tractor.

In addition the implements are adapted to be manually adjusted in or between their engaged and disengaged attitudes.

15 A difficulty associated with providing such implements is to ensure that the manual operation is safe, easy and convenient to use for the operators of such tractors.

The present invention aims to provide implement attachment means and implements therefor which will be reliable and efficient in use and which will adequately meet at least one of the above requirements.

With the foregoing in view, this invention in one aspect resides broadly in attachment means for light tractors including:mounting means for mounting an implement to a light tractor whereby the implement may be elevated and lowered; 2 manually operable elevating means for elevating the implement mounted on the mounting means; holding means for holding the elevating means in an elevating attitude; release means for releasing the holding means from its elevating attitude, and wherein said holding means operates automatically to hold the elevating means in its elevating attitude upon movement of the elevating means to its elevating attitude.

Preferably the holding means operates automatically to hold the elevating :o:°.means in its elevating attitude upon movement of the elevating means thereto and the elevated position is a position at which the implement is disposed clear of the S 10 ground.

However less desirably the holding means may be separately controlled such oo*oo as by a finger operated control associated with the hand grip of the manually operable elevating means and which may be operated to hold the elevating means at S any desired elevated position. The elevated position may be any position above the 15 lowest operating position of the implement and thus the holding means may also be .1 operable to hold the implement in a partly engaged attitude.

It is also preferred that the elevating means include a hand lever which is pulled back towards the driver's position on the light tractor in order to raise the implement. Furthermore it is preferred that the holding means is spaced from the hand grip of the hand lever such that one handed operation of the hand lever and the holding means is 3 prevented so as to reduce the chance of accidental lowering of the implement. A separate foot operated holding means may be used if desired.

In a further aspect this invention resides broadly in an implement positioning assembly for light tractors of the type having a mounting base at one side of the tractor, a bumper bar or other such laterally extending fixed abutment adjacent S.the front of the tractor and mounting means whereby an implement may be operatively mounted for movement between 10 elevated and lowered attitudes, the implement positioning *o assembly including:a lever assembly pivotally connectible to the mounting .:o.oi base; an adjustable strut for interconnecting the lever S 15 assembly to the mounting means whereby retraction of the strut towards the driving position of the tractor will elevate the mounting means; a drop down pawl member associated with the strut and the bumper bar or other fixed abutment and adapted to drop to a blocking position preventing return movement of the strut upon its movement to a retracted position, and manually operable release means for releasing the pawl member from its blocking position.

The implement positioning assembly may also include the adjustable mounting means which may be a pivot frame fixed to the implement and pivotally connectible to the tractor 4 whereby it may pivot about a transverse axis between its raised and lowered positions. Alternatively the adjustable mounting means may be in the form of a three point linkage or comprise upper and lower pivot frames.

The implement referred to in the above aspects may be mounted at the front or rear of the light tractor and suitably is a dozer blade which rests upon the ground when in its operative position. However the implement may be a plough assembly which is adapted to penetrate the ground when in its operative position. The mounting base may be a foot rest or it may be a portion of the tractor frame able to accept loads imposed by the implement.

S. In order that the present invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawing of a typical embodiment of the invention and wherein:- FIGS. 1 and 2 illustrate a dozer blade fixed to a light tractor and disposed in its operating and elevated positions respectively, and FIG. 3 is an exploded view of a dozer blade and attachment means for mounting the dozer blade to a ride-on mower.

A typically ride-on mower 6 includes a base frame shown broken away at 10 supported by steerable wheels 7 at the front and by driven wheels 8 at the rear. A bumper bar 11 typically extends across a forward extension of the base frame 10 and in this embodiment the forward extensions 12 are provided with upper and lower apertures 13. A fixed foot rest 14 in the form of an apertured running board is mounted rigidly to the left hand side of the machine 6 While the opposite side supports a complementary pivotable foot rest, not illustrated, which may be pivoted back and forward for selecting forward or reverse motion.

Such a ride-on mower 6 is adapted to be fitted with a dozer blade 15 by the implement attachment means illustrated 10 in the drawings. The implement attachment means includes a pivot frame 16 which is fixed to the dozer blade 15 and extends rearwardly therefrom to engage pivotally in bolt-on *mounting tubes 17 which bolt to the forward extensions 12 through the apertures 13. The mounting tubes 17 extend below the base frame 10 and receive the frame 16 therebetween, pivotally connected thereto by the through bolts The dozer blade 15 may pivot about the bolts 20 from a lower operative position, at which it rests upon the ground, upwardly to an elevated position clear of the ground enabling the tractor to be used for other purposes without having to detach the dozer blade from the mower.

The frame 16 is provided with an upwardly extending control arm 21 fixed thereto which is pivotally connected at its upper end to a length adjustable strut 23 which extends rearwardly from the control arm 21 alongside the base frame and above the bumper bar 11. Retraction of the strut 23 6 in a rearward direction towards the seated position of the driver causes the pivot frame 16 to pivot upwardly and to elevate the dozer blade 15 above the ground.

The rearward end 24 of the strut 23 is pivotally connected to a hand lever 25 by the bolt 27. The lever 25 is mounted at the side of the mower through a pivot mounting 26 bolted directly to the apertured foot rest 14. Thus the strut 23 may be retracted by a driver gripping the handle 28 and pulling the hand lever 25 rearwardly.

10 I- desired, the driver may grasp the hand grip 28 and push the lever 25 forwardly to apply a downward pressure on the dozer blade through the strut 23. Such action may be required when the weight of the dozer blade 15 is not sufficient to achieve the necessary penetration of the 15 surface being graded.

The front end of the strut is provided with a drop down pawl assembly 30 which is pivotally connected thereto by the bolt 31. The pawl assembly 30 has a front face 32 which may extend either downwardly beyond the strut 23 or above the strut 23 depending upon its pivotal orientation relative to the strut 23. This pivotal orientation is controlled by a tension rod 33 which engages an upstanding bracket 34 on the pawl assembly The tension rod 33 extends rearwardly through a slotted keeper plate 35 in which the looped trailing end of the rod 33 is held captive. The rod 33 is kinked at 36 at a position 7 which aligns with the keeper plate 35 at full retraction such that the rod 33 may be locked in the retracted position by moving the lateral portion 37 of the kink 36 down behind the keeper plate Normally the rod 33 is free to move with pivotal movement of the drop down pawl and the arrangement is such that the front face 32 of the pawl assembly 30 can drop down Sbehind the bumper bar 11 when the strut 23 is fully retracted to form an abutment which abuts the bumper bar 11 and prevents the strut 23 from returning from its retracted position. Thus in this position the dozer blade 15 will be retained in an elevated position.

oi ~The blade 15 may be lowered by pulling back the hand lever 25 to a sufficient extent to free the front face 32 of 15 the pawl assembly 30 from the bumper bar 11. Thereafter the rod 33 may be retracted to elevate the front face 32 of. the keeper plate 35 above the strut such that the strut 23 may move forward freely across the bumper bar 11 accompanied by lowering of the blade The underside face of the drop down pawl assembly extends from the front face and rearwardly to a position within a lateral projection of the strut so that it will be automatically elevated in a cam like manner upon rearward passage across the bar 11. Provided the rod 33 is unlocked from the keeper plate 35 the pawl will drop down automatically immediately it passes over the bar 11.

8 In the event that the rod 33 is maintained in a locked position, with the lateral portion 37 behind the keeper plate the blade will be free to move freely up and down through its full arc of movement. A limiting chain 40 is connected between the mountings 17 and the dozer blade 15 so as to limit the amount of downward movement of the blade 15 and the strut 23 is a two piece strut provided with alternative connecting apertures 22 whereby it may be length adjustable ooo o' to suit different machines. It will be also seen that the 10 rod 33 is provided with alternate offsets 41 at its forward end to suit the length adjustments of the strut 23.

In use a user may drive or mow with a ride-on mower fitted with a dozer blade by maintaining the dozer blade in an elevated position. When the blade is required for use the 15 rider simply grasps the lever 25 with one hand and locks the rod 33 with the keeper 35 with the other hand-so that the drop down pawl 30 is pivoted to its elevated non-retaining S"position. The lever 25 may then be released to allow the blade 15 to drop to the ground. In that position the ride-on mower may be used as a small grader in conventional manner.

The bottom edge of the dozer blade 15 is suitably reinforced with a Z-shaped fabrication which provides a base wall upon which the blade may rest and move evenly across the ground.

It will of course be realised that the above has been given only by way of illustrative example of the invention 9 and that all such modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as is defined in the appended claims.

o

Claims (7)

1. Attachment means for light tractors including:- mounting means for mounting an implement to a light tractor whereby the implement may be elevated and lowered; manually operable elevating means for elevating the implement mounted on the mounting means; holding means for holding the elevating means in an elevating attitude; release means for releasing the holding means from its elevating attitude, and wherein said holding means operates automatically to hold the elevating means in its oooo S 10 elevating attitude upon movement of the elevating means to its elevating attitude.

2. Attachment means as claimed in claim 1 and including locking means for .preventing said holding means from operating automatically to hold the elevating means in its elevating attitude. S"

3. Attachment means as claimed in claim 1, wherein said elevating means includes a hand lever which is pulled back towards the driver's position on the light tractor in order to raise the implement.

4. An implement positioning assembly for light tractors of the type having a mounting base at one side of the tractor, a bumper bar or other such laterally extending fixed abutment adjacent the front of the tractor and mounting means whereby an implement may be operatively mounted for movement between elevated and lowered attitudes, the implement positioning assembly including:- 11 a lever assembly pivotally connectible to the mounting base; an adjustable strut for interconnecting the lever assembly to the mounting means whereby retraction of the strut towards the driving position of the tractor will elevate the mounting means; a drop down pawl member associated with the strut and the bumper bar or other fixed abutment and adapted to drop to a blocking position preventing return movement of the strut upon its movement to a retracted position, and manually operable release means for releasing the pawl member from its blocking position.

An implement positioning assembly as claimed in claim 4, wherein said drop down pawl member is pivotally mounted on the strut and is adapted to drop down behind the bumper bar or other fixed abutment when the strut is S"retracted.

6. An implement positioning assembly as claimed in claim 4 or claim 5, wherein the adjustable mounting means is a pivot frame fixed to the implement and *pivotally connectible to the tractor whereby it may pivot about a transverse *axis between its raised and lowered positions.

7. An implement positioning assembly as claimed in claim 6, wherein the implement is a dozer blade. DATED THIS 22 ND DAY OF MARCH 2001 BARTLEM PTY LTD BY PIZZEYS PATENT TRADE MARK ATTORNEYS