WO2001011938A1

WO2001011938A1 - Lifting and lowering linrage arrangements for agricultural implements connected to prime movers

Info

Publication number: WO2001011938A1
Application number: PCT/AU2000/000970
Authority: WO
Inventors: Kevin James Skerman
Original assignee: Tanusi Pty Ltd
Priority date: 1999-08-13
Filing date: 2000-08-14
Publication date: 2001-02-22
Also published as: AUPQ221099A0

Abstract

An agricultural implement of the type having a main body (11) and at least one rear ground wheel (12a), the implement having means for moving the implement between a raised transport position and a lowered working position, the means comprising: a) a first arm member (18a) having a forward end (15a) and a rear end (20a), the forward end (15a) being attachable to a prime mover (17) and the rear end (20a) being pivotally attachable to the main body (11) about a substantially horizontal axis, b) a first extension and retraction means having two ends, one said end attached to the first arm member (13a), c) a second arm member (22a) which is rigidly attached to the main body, the other end of the first extension and contraction means (21a) being attached to the second arm member (22a), the construction and arrangement being such that the operation of the first extension and contraction means (21a) causes the main body (11) to be raised and lowered relative to the ground, and a second extension and contraction means which has one end attached to the main body and the other end operatively associated with the rear wheel (12a) such that operation of the second extension and contraction means (25a) causes the main body (11) to be raised and lowered relative to the rear wheel (12a).

Description

LIFTING AND LOWERING ARRANGEMENTS FOR AGRICULTURAL IMPLEMENTS CONNECTED TO PRIME MOVERS

FIELD OF THE INVENTION This invention relates to improvements of connecting agricultural implements to a prime mover such as a tractor. 5 BACKGROUND ART

Agricultural implements need to be connected to a prime mover in such a way to have good maneuverability, good ground following or tracking ability, controlled lifting and lowering of the implements relative to the ground, and where applicable, having optimum power take off (PTO) drive 0 configurations.

There are many known systems to attach an agricultural implement to a tractor or other type of prime mover.

One system is a trailing system. This system has a disadvantage in that it makes the tractor-implement combined length very 5 long. This requires a large area for turning on headlands, with the result of too much wasted land. This system is not suitable for irrigated land where irrigation requires a very narrow headland. Because of a horizontal angle component introduced while turning, this system is not ideal for PTO driven implements as it provides great stress and strain on the PTO. 0 Another well-known system is the standard 3-point linkage on the rear of a tractor. The standard 3-point linkage is extremely well-known and consists of two lower horizontal linkage points and a third operated linkage point which can raise or lower equipment attached to the 3-point linkage. One disadvantage with this linkage arrangement is that while lifting 5 or lowering PTO driven equipment, the angle of the universal joint at the tractor PTO outlet and at the implement PTO inlet is not maintained equally while lifting. This introduces vibration into the drive which in turn creates forces which have highly damaging effects to all power transmission parts including the tractor mechanical power outlet, the PTO shaft, and the 0 implement drive parts.

For larger and heavier agricultural implements, the standard 3- point linkage itself is unable to lift the implement off the ground. With these

Substitute Sheet ca_uiβ 26) κo/Aυ arrangements, the implement has at least one and usually two rear ground wheels. These rear ground wheels are hydraulically operated by rams and the trailing angle of the rear ground wheels can be increased or decreased by the rams. The effect of this is to raise or lower the rear part of the implement. This arrangement is quite well-known on larger implements. The front of the implement is attached to the 3-point linkage of the tractor. The problem here is that the front of the implement is controlled by the hydraulics on the tractor while the rear of the implement is lifted or lowered by hydraulics on the implement. Because there is no control between the 3-point linkage and the hydraulics on the rear wheel, there is no way to guarantee parallel and synchronised lift between the front and the rear of the implement. This has an adverse influence on the PTO and on the normal function of the implement at the beginning of work engagement.

Different types of prime movers and tractors have different lifting rates and mechanisms and it is difficult if not impossible to correctly match the equipment to the tractor.

OBJECT OF THE INVENTION The present invention is directed to an agricultural implement which has at least one rear ground wheel which can be operated by a ram and where the implement is provided with its own forward lifting means which is attached to the prime mover. That is, the lifting means of the prime mover is not used. The lifting and lowering of the agricultural implement is controlled by the implement itself and does not require any additional lifting from the prime mover. In an embodiment, the two lower attachment linkages of the 3- point linkage are used to attach the implement to the tractor, but the top link is kept free.

It is an object of the invention to provide an agricultural implement which may overcome the abovementioned disadvantages or provide the public with a useful or commercial choice.

In one form, the invention resides in an agricultural implement of the type having a main body and at least one rear ground wheel, the

Substitute Sheet (Rule 26) RO/AU implement having means for moving the implement between a raised transport position and a lowered working position, the means comprising: a first arm member having a forward end and a rear end, the forward end being attachable to a prime mover and the rear end being pivotally attachable to the main body about a substantially horizontal axis, a first ram having one end attached to the first arm member, a second arm member which is rigidly attached to the main body, the other end of the first ram being attached to the second arm member, the construction and arrangement being such that operation of the first ram causes the main body to be raised and lowered relative to the ground, and a second ram which has one end attached to the main body and the other end operatively associated with the rear wheel such that operation of the second ram causes the main body to be raised and lowered relative to the rear wheel.

The agricultural implements can be of various types and can include a mulcher, a cultivator, crop cleaning, cutting, shredding implements, soil working implements, crop collecting and baling implements, and the like. No limitation is meant to be made on the particular type of agricultural implement.

The agricultural implement is of the type having a main body and at least one rear ground wheel. Many agricultural implements are provided with a ground wheel, but it is envisaged that if an implement is not, a ground wheel can be attached. Although the invention is described with reference to a ground wheel, the wheel itself is to be construed broadly and may include a pneumatic wheel, a disc wheel, a spoke arrangement, or even a slide, skid, and the like.

The agricultural implement has means for allowing the implement to be moved between a raised transport position and a lowered working position.

The means has a first arm member which is generally in front of the main body of the implement. The main body of the implement can include

Substitute Sheei the main working features, the transverse frame member or crossbars, and the like. The first arm member has a forward end and a rear end. The forward end of the arm member is attachable to a prime mover. In one form, the prime mover is a tractor and the forward arm can be attached to one of the lower linkages of the 3-point linkage. This can be achieved by any suitable means including a pin coupling, a hook and eyelet, or any other type of suitable attachment arrangement. The rear end of the arm member is attached to the main body in such a way that the arm member can pivot up and down. The implement typically contains a pair of spaced apart first arm members, each arm member coupling with one of the two lower linkages on the tractor. The arm members are to be construed broadly and may include a framework system, or any other type of arrangement which attaches the implement to the prime mover and which can pivot up and down relative to the main body of the implement. If a pair of spaced apart arm members are used, these can be cross-braced by struts or braces if desired and to provide rigidity and robustness to the arrangement.

A first ram is provided which has one end attached to the first arm member. The ram is typically a hydraulic ram although other types of rams are also envisaged. A typical ram has a ram body and a ram piston with the end of the piston constituting one end of the ram and the end of the ram body constituting the other end of the ram. Rams are extremely well-known in the art. Other forms of extension and contraction means other than rams are envisaged. For instance, worm drives, rack and pinion drives, other types of mechanical drives including those using line members, cable or cords are envisaged, although it is found that a ram is the most convenient.

The means further includes a second arm member. The second arm member is attached to the main body and the ram is attached to the second arm member. The second arm member is itself not hingedly attached relative to the main body and provides a push or pull stop for the ram. The first arm and the second arms are angled relative to each other typically by about 90° and the ram works between the arm members.

Substitute Sheet 26₎ RO/AU The construction and arrangement therefore is such that operation of the ram will cause the angle between the two arm members to vary. As one arm member is fixed to the main body and the other arm member can pivot relative to the main body, the result is that operation of the ram member will cause the front of the implement to raise above the ground or be lowered to the ground.

The second arm member is again to be construed broadly and may include a part of the implement body or any other type of anchor point for the first ram. The implement further has a second ram which is operatively connected to the at least one rear wheel to cause the trailing angle of the rear wheel to vary. This in turn creates a lifting or lowering effect on the rear of the implement.

The combination of the first ram (also called the front ram) and the second ram (also called the rear ram) can result in good efficient lifting or lower of the implement while keeping the rear wheel on the ground. BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the invention will be described with reference to the following drawings in which Figure 1 is a plan view of an agricultural implement according to an embodiment of the invention.

Figure 2 is a side view of the implement of Figure 1 in the lowered position.

Figure 3 is a view of the implement of Figures 1 and 2 in a raised position.

BEST MODE Referring to all the figures together, there is shown an agricultural implement 10 of the type which has a main body 11 and at least one rear ground wheel (in the embodiment two ground wheels 12A and 12B are provided). The implement has a means for moving the implement between a raised transport position illustrated in Figure 3 and a lowered working position illustrated in Figure 4 the means being described in greater

Substitute Sheet detail as follows:

The implement has a pair of spaced apart first arm members 13A, 13B which can be made from steel box section rod or other suitable material. Arm members 13A, 13B are braced by cross struts 14 to provide a strong rigid unit. Each arm member 13A, 13B has a forward end 15A, 15B which is attachable to the two lower arms 16 of a standard 3-point linkage extending from the rear of tractor 17. The 3-point linkage from tractor 17 is entirely conventional.

Illustrated in the figures but not necessarily required for each implement is the power take off (PTO) 18 which drives a drive means 19 in implement 11 and which provides drive power to the implement. Some implements have their own source of power and therefore a PTO is not always required.

Each arm member 13A, 13B has a rear end 20A, 20B pivotally attached to main body 11 in such a way that it can pivot up and down.

Extending above each arm member 13A, 13B is a first ram 21A, 21 B which is a hydraulic ram. The ram is a conventional type and consists of a ram body and a ram piston. In the embodiment, the ram piston is attached to the respective first arm member 13A, 13B. Attached to main body 11 or thereabouts are a pair of second arm members 22A, 22B (only one arm member shown in Figures 2 and 3). Arm member 22A, 22B functions as a stop for the respective ram 21 A, 21 B and the ram body of each respective ram is attached to or relative to second arm members 22A, 22B. The result of this attachment arrangement is that when the ram is in the retracted position (illustrated in Figure 2) the implement is in a lowered working position. Upon extension of the ram to the extended position illustrated in Figure 3, the front of the implement is raised above the ground surface to a transport position. This lifting action acts in combination with the lifting action of rear wheels 12A, 12B.

Rear wheels 12A, 12B are rigidly attached to a rotatable rod

Substitute Sheet (Rule 26) RO/AU 23A, 23B (best shown in Figure 1 ). Each end of each rod is supported by a bearing block 24 in a conventional manner. The wheels 12A, 12B are rigidly attached to each rod which means that rotation of each rod about its longitudinal axis will cause the wheels to move between a more inclined position illustrated in Figure 2 which causes the rear end of the implement to be lowered, to a less inclined position illustrated in Figure 3 which causes the rear of the implement to be raised.

Rods 23A, 23B are rotated by respective second rams 25A, 25B. Extension of ram 25B causes the rear wheels to be rotated closer to the implement and therefore raising the implement (illustrated in Figure 3) while retraction of the ram provides the opposite effect (illustrated in Figure 2).

In use, the forward rams 21 A, 21 B and the rear rams 25A, 25B work together to cause even lifting and lowering of the main body 11. For instance, they may be linked hydraulically or linked in another fashion. The tractor itself does not assist or function in lifting or lowering the implement and all lifting or lowering is done by the implement itself.

The rear wheels 12A, 12B in the embodiment can swivel when the implement is lifted (Figure 3) which allows the tractor to turn around. When the main body is lowered to the working position illustrated in Figure 2, the wheels are locked in the position illustrated in Figure 1.

The implement assembly according to the invention has many advantages. A very short turning radius and improved maneuverability is found. The close coupling makes the tractor-implement combined length quite short. The implement has good ground following because of the proximity of the tractor wheels to the implement. All the lifting functions are controlled within the implement and does not rely upon the tractor 3-point linkage hydraulics. The implement will suit any tractor with standard linkage arms or other types of prime movers. The weight transfer to the tractor rear wheels improves traction efficiency while working. The PTO shaft drive is greatly simplified and made more robust.

The universal joints are unaffected by sharp turns and the level lifting action maintains equal angles on the joints at all times. There is very little or no

Substitute Sheet (Rule 26) RO/AU mismatch on the universal joints of the PTO shaft during the lifting and lowering action. A positive steering is provided because, during the turns, the rear weight of the implement is carried by the wheels and is not supported only by the back of the tractor which can reduce grip of the tractor front wheels. A simple single lever action can be positioned on the tractor to control the lift of the implement.

It should be appreciated that various other changes and modifications may be made to the embodiment described without departing from the spirit and scope of the invention.

Substitute Sheet (Rule 26) RO/AU

Claims

CLAIMS:

1. An agricultural implement of the type having a main body and at least one rear ground wheel, the implement having means for moving the implement between a raised transport position and a lowered working position, the means comprising: a first arm member having a forward end and a rear end, the forward end being attachable to a prime mover and the rear end being pivotally attachable to the main body about a substantially horizontal axis, a first extension and retraction means having two ends, one said end attached to the first arm member, a second arm member which is rigidly attached to the main body, the other end of the first extension and retraction means being attached to the second arm member, the construction and arrangement being such that operation of the first extension and retraction means causes the main body to be raised and lowered relative to the ground, and a second extension and retraction means which has one end attached to the main body and the other end operatively associated with the rear wheel such that operation of the second extension and retraction means causes the main body to be raised and lowered relative to the rear wheel.

2. The implement of claim 1 , wherein the first and second extension and retraction means are rams.

3. The implement of claim 2 comprising a pair of spaced apart first arm members.

4. The implement of claim 2, wherein the prime mover has a 3 point linkage comprising an upper linkage and a pair of lower linkages, each said arm member adapted for coupling with one of the two lower linkages on the prime mover.

5. The implement of claim 4, wherein the first and second rams are hydraulic rams.

6. The implement of claim 5, wherein the main body has the working features of the implement.

Substitute Sheet (Rule 26) RO/AU

7. The implement of claim 6, wherein the first and second arm members are angled relative to each other and define an angle of about 90 ° .

8. The implement of claim 7, wherein operation of the first ram causes the angle between the first and second arm members to vary which causes the front of the implement to rise and fall.

9. The implement of claim 8, wherein the second ram operates in combination with the first ram to lift and lower the implement relative to the ground.

10. The implement of claim 9, wherein the prime mover has a PTO, and implement is powered by the PTO of the prime mover.

Substitute Sheet (Rule 26) RO/AU