GB2187627A

GB2187627A - Tractor attachment linkage

Info

Publication number: GB2187627A
Application number: GB08625175A
Authority: GB
Inventors: Malcoln Henry Beanland
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-03-15
Filing date: 1986-10-21
Publication date: 1987-09-16
Anticipated expiration: 2006-10-21
Also published as: GB8625175D0; GB2187627B; GB8606430D0

Abstract

There is provided a linkage for a ground-engaging agricultural implement such as a furrow press, comprising an attachment arrangement adapted to be attached to the front of an agricultural tractor 1 and to be swung between a raised transport position for the implement, and two operating ground-engaging positions for the implement, one on either side of the tractor. The swinging movement is achieved by means of a hydraulic ram 6 acting on a swinging arm 5. Lateral positioning of the implement is achieved in synchronism with the swinging movement by means of a chain drive 16 between a sprocket 14 fixed on the axis of the swinging arm 5 and a sprocket 15 at the end thereof attached fixedly to a swinging support mechanism 8. <IMAGE>

Description

SPECIFICATION Tractor attachment linkage This invention relates to tractor attachments, more specifically to a linkage, and more particularly, but notexciusivelytoan improved implement linkage for directly and positively coupling a furrow press or other ground-engaging agricultural implement to an agricultural tractor. The invention also comprehends such an implement, especially afurrow press, in conjunction with such a linkage.

Afurrow press is an implement which consists of one or more series of rings or wheels which are passed over the soil immediately our shortly after ploughing to provide a measure of consolidation and to break up large clods. The furrow press is normally towed behind a tractor, using an auxiliary drawbar, to act on areas ploughed on a previous pass. The use of a furrow press has recently come into normal practice after a period of time when its use was largely confined to consolidating puffy soils. This is largely due to the recent increase in the practice of ploughing-in straw instead of burning it. Ploughing in the straw tends to fluff up the soil, and the use ofa furrow press increases the consolidation to bring the straw into more intimate contact with the soil and reduce cavitation.

The furrow press is normally entrained by a laterally extending auxiliary drawbar on the plough, and is released and re-entrained at the end of each furrow. Such an arrangement is very inflexible and tends to mean thatthe furrow press cannot be used on a run where there is an obstruction such as a tree or post for overhead wire, around which the tractor needs to manoeuvre, possibly by temporarily raising the plough, which disentrains the furrow press. Also, there is difficulty in using the furrow press on the headlands at the periphery of a field, which are not ploughed buy a back and forth operation.

Further, the transport of the furrow press entails either a second tractor or a second run with the same tractor, since with the plough it makes an excessively wide combination and so cannot negotiate gates or roads, apart from the fact that the raising ofthe plough to transport position disentrains the furrow press.

In accordance with a first aspect of the present invention, there is provided a linkage for a ground-engaging agricultural implement such as a furrow press, comprising an attachment arrangement adapted to be attached to the front of an agricultural tractor and to be swung between a raised transport position for the implement, and two operating ground-engaging positionsforthe implement, one on either side of the tractor.

The furrow press, or other implement, may thus be out of use for a minimum area in relation to obstructions, may be used on the headlands, and may be easily transported simultaneouslywith the associated plough.

It will be appreciated that the invention may be applied to implements such as mowers, verge trimmers or hedge cutters as well as furrow presses.

The swinging movement may be achieved by means of a hydraulic ram. The attachment may include a hydraulically operated telescopic arm for lateral positioning ofthefurrowpress or other implement in relation to the tractor.

It has also been found that having the furrow press or other implement on the front of the tractor leads to a degree of counterweighting, so thatthefore and aft balance ofthe tractor is improved, along with its efficiency and safety.

In an alternative and preferred arrangement, the lateral positioning of the implement may be achieved in synchronism with the swinging movement by means of a mechanical connection, particularly a chain drive between a sprocket fixed on the axis of a swinging arm and a sprocket at the end thereof attached fixedly to a swinging support mechanism.

Such a chain drive may be usable with a swinging arm linkage of other types, and in accordance with a second aspect of the invention, there is provided a swinging arm linkage, particularly when mounted on an agricultural tractor, including afirstarm swingable about a first axis, and a second arm swingable relative to the first arm about a second axis fixed on the first arm, in which the swinging motion ofthe second arm is achieved in synchronism with the swinging movement ofthe first arm by means of a chain drive between afixed sprocket on the first axis and a movable sprocket on the second axis and connected to the second arm.

In a chain drive ofthistype, only small parts ofthe loop run over the sprockets and therefore need to be made up of chain links, so it is possibleto incorporate solid linkage, and particularly a chain tensioner, say of the turnbuckle type, in the part of the loop which does not run over the sprockets.

In accordance with a third aspect of the invention, there is provided an agricultural implement, particularly a furrow press, in combination with a linkage in accordance with the invention as set forth above.

The invention will be further described with reference to the accompanying diagrammatic drawings of a preferred embodiment ofthe invention, and in which: Figure lisa side elevation of a front-mounted furrow press on a tractor; Figure 2 is a front elevation ofthe arrangement of Figure 1 showing the furrow press in a transport position; Figure3is a viewsimilarto Figure 2 showing the furrow press in an intermediate position; Figure4is afurtherviewsimilarto Figures2 and3 showing the furrow press in a ground-engaging position; Figure 5is a plan view showing the furrow press in a ground-engaging position; and Figure6isaviewsimilarto Figure 5 and showing an alternative construction.

In the embodiment of Figures 1 to 5, an agricultural tractor 1 is shown as having the conventional front 2 and rear 3 wheels. Aforward mounting bracket 4 has mounted thereon afirstswinging arm Sforswinging about a horizontal axis 5a, and a hydraulic ram 6 is pivoted to both the arm 5 and the bracket 4. Control ofthe ram 6 is from the tractor cab 7, using hydraulic powersupplied by the tractor 1. The controls are such thatthe ram 6 may be locked in a required position by closing the hydraulic lines, so that continued hydraulic pressure is not required.

Asecond forwardly extending composite arm 8 is swingable about a horizontal axis 8a fixed in the arm 5and is pivotally attached to a frame 9 of a furrow press 1 1, of which the discs or wheels are diagrammatically illustrated as two series 12 and 13.

The furrow press 11 is suspended from the arm 8, by a series of links which allow some play to enablethe furrow press 11 to ride over uneven ground. For steering, theforward connection will allow less lateral movementthan the rear connection.

Fixed on the axis 5a is a first sprocket 14, and a second smaller sprocket 15 is fixed to the composite arm 8for rotation aboutthe axis 8a. Achain drive 16 connects the sprockets 14 and 15.

In use, it will be seen thatthefurrow press 11 may be transported in a position, as shown in Figure 2, in which it is suspended in a cantilever fashion from the front ofthe tractor, in a central position corresponding with a mid-pointofthe movement of the ram 6. In the transport position, the arm 8 hangs generally vertically. From this transport position it may be swung, using the ram 6, to an operational ground-engaging position ofthe furrow press 11 on either side ofthe tractor 1. Figure 3 shows an intermediate position in this movement, and Figure 4 shows the furrow press 11 in a ground-engaging position.

During swinging ofthe arm S,the chain 16 is held substantially static by the sprocket 14, so that as the arm 5 swings, the sprocket 15 at its distal end is rotated bythe chain 16 and causes the arm 8 to swing aboutthe axis 8a, from its vertical position in the transport position, to extend the position of the furrow press 11 successively further to the side as the swinging continues. By this means, the vertical movement to be applied to the furrow press 11 ,for a given lateral travel, is reduced.

By making the attachment of the arm 8 to the forward end of the frame 9, the fu rrow press is effectively pulled, ratherthan pushed, by the tractor 1. Positive attachment ofthe press to the tractor also enables the use of the furrow press on the headlands and in the region of obstructions. Itwill be noted that the furrow press is attached to the tractorforward of thefrontwheels, butithas been determined that with furrow presses of normal weightforthe application, this will not adversely affectthe equilibrium. Itwill also be noted that by using the chain drive mechanism, only one hydraulic control is requiredforthe linkage.

In a modification, as shown in Figure 6, the chain drive is replaced by an arrangement in which the arm Sbis madetelescopicallyextendable, by hydraulic means, so asto have an extension Sc carrying the forwardly extending arm 8. The exact position of ground-engagement may thus be varied by extension ofthe arm 5b whilethe furrow press 11 is clear ofthe ground.

Various modifications may be made within the scope of the invention. For instance, since the chain 16 does not all run overthe sprockets 14 and 15, it is not necessaryforthe loop to be formed completely of chain links. Thus, part of the loop may be formed by one or more rods connected to the chain iengths, and it may be particularly advantageous to incorporate a chain tensioner, for example of a turnbuckletype, in the loop.

Also, the description above is directed to the use of a furrow press, but it will be appreciated thatthe same linkage may be used forthe attachment and control of other implements.

Claims

1. Alinkageforan implement such asafurrow press, comprising an attachment arrangement adapted to be attached to the front of an agricultural tractor and to be swung between a raised transport position forthe implement, and two operating ground-engaging positions forthe implement, one on either side of the tractor.

2. A linkage as claimed in claim 1, in which the swinging movement is achieved by means of a hydraulic ram.

3. Alinkageasclaimed in claim 1 or2, in which the attachment arrangement includes a hydraulically operated telescopic arm for lateral positioning ofthe furrow press or other implement in relation to the tractor.

4. A linkage as claimed in claim 2, in which the lateral positioning of the implement is achieved in synchronism with the swinging movement by means of a mechanical connection.

5. A linkage as claimed in claim 4, in which the mechanical connection is constituted by a chain drive between a sprocket fixed on the axis of a swinging arm and a sprocket atthe end thereof attached fixedly to a swinging support mechanism.

6. A linkage as claimed in claim 5, in which the loop of chain incorporatesachaintensioner.

7. Alinkageforan agricultural implement, such as a furrow press, substantially as hereinbefore described with reference to the accompanying drawings.

8. An agricultural implement, particularly a furrow press, in combination with a linkage as claimed in any of the preceding claims.

9. Aswinging arm linkage including afirstarm swingable about a first axis, and a second arm swingable relative to the first arm about a second axisfixed on the first arm, in which the swinging motion of the second arm is achieved in synchronism with the swinging movement of the first arm by means of a chain drive between a fixed sprocket on the first axis and a movable sprocket on the second axis and connected to the second arm.

10. A linkage as claimed in claim 9, in which the loop of chain incorporates a chain tensioner.

11. A linkage as claimed in claim 9 or 10, when mounted on a n an agricultural tractor.