GB2176981A

GB2176981A - Agricultural cultivator

Info

Publication number: GB2176981A
Application number: GB08611612A
Authority: GB
Inventors: Theo Van Laak
Original assignee: Lemken GmbH and Co KG
Current assignee: Lemken GmbH and Co KG
Priority date: 1985-06-22
Filing date: 1986-05-13
Publication date: 1987-01-14
Also published as: GB2176981B; DK275586D0; DK275586A; GB8611612D0; DE3522362A1; FR2583606A1

Abstract

Wide cultivating implements can be transported in a longitudinal direction on separate wheels by means of a drawbar (2) pivotable from the working position into the transport position and vice versa, the drawbar being designed to be automatically lockable in and releasable from the relevant extreme positions. Care has been taken to ensure that the pivoting drawbar does not assume any dead centre position in that the straight lines (9, 9') (or extensions thereof) formed by the tractor-end (11) and implement-end (7) points of articulation of the drawbar do not intersect the point of resistance (8) of the implement. <IMAGE>

Description

angular or curved according to the desired method of simplest and most expedient locking and releasing of the implement in the individual extreme positions. Therefore, the embodiment of drawbar which is discussed hereinafter must be regarded as only one of various possibilities.

In particular, the invention is characterised in that even very wide implements may be time-savingly employed, the ground being protected from compaction and other damage because the area is overrun fewer times, which means that overall costs are reduced while there is no need to modify the wide appliances as such. For example, it is possible to dispense entirely with pivoting-in devices for altering the working width and reducing it to an admissible size. Furthermore, the centre of gravity is favourably low. It is possible advantageously to use the implement according to the invention, particularly ifl the form of packers, since by reason of the low centre of gravity, it is impossible for the implement to tip over. Also advantageous is the favourable locking-up of the wheels, so that these implements can also be run easily over ordinary field tracks.Since the implement according to the invention is always rigidly connected to the tractor, there is no need to uncouple and afterwards recouplethe supply lines at the implement end. This is firstly an operating advantage and secondly has the advantage of minimising dirt and thus the risk of individual control devices failing, because uncoupling and recoupling are operations where the supply lines for brakes, lights and control devices can pick up dirt.

Further details and advantages of the object of the invention will become evident from the ensuing description of the associated drawings which show a preferred example of embodiment, together with the details and components needed therefor. In the drawings: Fig. lisa plan view of an implement in the transport position; Fig. 2 is a plan view of an implement in the working position, and Fig. 3 is a plan view of an implement with the straight lines connecting the points of articulation.

In the drawings explained hereinafter, the implement 1 is only shown diagrammatically, since the nature of working tools used is not essential to the manner in which the implement 1 operates. The implement 1 has a drawbar 2 which is pivotally attached to the frame 3 which carries the working tools. The frame 3, as Fig. 1 shows, is in the transport position supported by the two wheels 4, 5.

These wheels 4,5 are mounted in the region of the cross-members 6, 6' and, in the example shown, the cross-member 6 carries the implement-end point of articulation 7 for the drawbar while the crossmember 6' strengthens the frame 3 in the region of the points of articulation of the wheels 4, 5.

Substantially centrally of the implement is the centre of gravity or resistance point 8. The resistance point 8 is free to move according to the type of working tools or whatsoever is being carried by the frame 3. It will however in each case be located beyond the straight lines 9, 9' explained in Fig. 3. These straight lines 9, 9' pass through the implement-end point of articulation 7 and the tractor-end point of articulation lithe tractor-end point of articulation 11 lying for example in the axis of rotation between drawbar 2 and articulating linkage 10.

The articulating linkage 10 is provided for a conventional tractor and allows the connection between the bottom links of the tractor and the drawbar 2 without considerable complication. The tractor simply drives up to the implement and the drawbar 2, its bottom links grip the articulating linkage 10 and so the operative connection is established between the implement 1 and the tractor.

The drawbar 2 is pivotally articulated on the frame 3 and can be independently locked in the relevant extreme positions, i.e. on the one hand in the working position shown in Fig. 2 and on the other in the transport position shown in Fig. 1. For this purpose, locking bolts 12 and 13 are provided which engage automatically when the drawbar 2 is pivoted out of one position and into the other.

Fig. 3 shows the changeover of the implement from the working position into the transport position. For this, the drawbar 2 is first released, for example by Bowden type control cable or hydraulically, the locking bolt 12 being moved into a position which releases the drawbar 2. Now the tractor, not shown here, moves forwards so that the implement is pivoted through 90C since the drawbar 2 has its axis of symmetry passing through the point of articulation on the implement 1. Since a dead centre position is avoided, the implement 1 swings round fully. As soon as the drawbar 2 is in its extreme position on the frame 3, the locking bolt 13 automatically engages so that the drawbar 2 is fixed. Now the wheels 4, 5 are lowered and thus the entire implement is lifted for transport.Afterwards, the tractor driver can set his implement in motion and both, i.e. both the tractor and the implement 1, can be transported to the next workplace. Fig. 3 shows that the straight line 9' or 9 does not intersect the resistance point 8 during the pivoting process described. Thus, a dead centre position is reliably prevented. In both positions, the point of articulation 11 lies in the axis of symmetry 14 or axis of symmetry 15.

When changing over from the transport position to the working position, the process is reversed exactly. Firstly, the wheels 4, 5 are raised and thus the implement is lowered to the ground. Then the drawbar 2 is released by releasing the locking bolt 13 by Bowden control, electrically, hydraulically or possibly even mechanically, so that the drawbar can now be pivoted again by the tractor, not shown. For this purpose, the tractor need only travel in reverse in orderto push the implement 1 into the working position. When the working position is reached, the drawbar 2 is again locked on the frame 3 in that the locking bolt 12 automatically operates. The drawbar 2 is then in the position shown by the broken lines, and it is clear that now the implement can start work over its full width when the tractor is set in motion.

SPECIFICATION Agricultural cultivator The invention relates to an apparatus for cultivating soil in agriculture and which, with a considerable working width, can be transported in a longitudinal direction on separate wheels.

For working soil in agriculture, implements of considerable working width are used wherever large and regular areas of soil have to be cultivated, these implements which may be over 3 m wide only being capable of being transported on the road in a position crosswise to the working direction. Such an implement is known from Swedish Published Specification 326 332, the points of articulation required for it being provided on the long side for the working position and on the narrow sides for the transport position. For the working position, a drawbar is provided whereas for the transport position, a short articulating linkage is used.While the implement, in the case of the working position, is supported directly on the soil through its working tools, a pair of wheels serves as a support means on the road and is mounted on the opposite side to that which comprises the articulating linkage. A disadvantage thereby is that the wheels always have to be removed for working in the field and then attached again for transport purposes. For attachment, the implement must first be raised by the tractor which must assume a third position for the purpose. The cost in terms of labour and time is quite considerable, apart from the fact that the working width of the implement is limited because the wheels have always to be mounted at the outer end, so that the frame of the implement must be made to be correspondingly heavy.

The invention is based on the problem of so constructing such an implement that it can be moved into the working position or transport position respectively without considerable effort and from the tractor, particularly without any need for the tractor driver to leave his workplace.

According to the invention, the problem is resolved in that the drawbar is constructed to be pivotable from the working into the transport position and vice versa, the straight line or the extension thereof which is formed by the real or ideal drawbar articulation points at the tractor end and implement end respectively does not intersect with the centre of gravity or resistance point of the implement.

Where such an implement is concerned, it is surprisingly possible to swing round from the working position into the transport position without the tractor driver having to leave his vehicle. In order to move from the working position into the transport position, he need only detach the mounting of the drawbar and then drive away, the implement or initially the drawbar automatically swinging into the transport position. If he wants to move from the transport position into the working position, then the tractor driver must once again detach the mounting of the drawbar and push back with the tractors that the drawbar again swings automatically into the working position, so that he can then use the implement for cultivating the soil.It goes without saying that after swinging round from one position into the other, he must in each case move the wheels also into the corresponding position so that in the transport position they support the overall implement and in the working position they leave the working tools free to operate.

According to an expedient development of the invention, it is envisaged that the drawbar be constructed to be independently lockable in the extreme positions. This dispenses with the need for the tractor driver to secure the drawbar when the extreme position is reached. This locking process takes place automatically.

So that releasing of the locking bolts can also be undertaken automatically from the tractor vehicle, it is according to the invention envisaged to provide release means which can be operated from the tractor and which are associated with the locking bolts. In the case of such release means, a Bowdentype control or more expediently small hydraulic cylinders may be used which cancel out the automatic lock in the extreme position so that the drawbar can then be pivoted into whichever is the other position by the tractor.

Coupling of the apparatus to tractor vehicles is possible without any considerable effort because, according to an advantageous development of the invention, it is envisaged to equip the drawbar with an articulating linkage for the bottom links of the tractor. Thus, the tractor only needs to be driven up to the implement and the articulating linkage picked up in order to achieve a connection between the two parts of the implement.

The effort needed to change from the working position into the transport position or vice versa is according to the invention further reduced considerably in that changing or fitting of wheels can be dispensed with entirely. Instead, according to the invention, the wheels are constructed to be pivotable. They can thus without considerable effort be either raised up or lowered into the transport position, these different positions being adjustable from the driver's seat on the tractor. Thus it is completely unnecessary to leave the tractor when making the conversion. It is particularly simple to bring about the change from one position to the otherfrom the tractor vehicle in that namely hydraulic working cylinders are associated with the wheels. It is both possible to pivot the wheels from one position into the other or simply to raise or lower them.

Both in order to facilitate a change of position and also to ensurethatthe apparatus orthe implement follows the tractor exactly, it is according to the invention envisaged that the tractor-end point of articulation in the relevant extreme position lie virtually in the axis of symmetry of the implement in the working position or the transport position. If the axis of symmetry of the working position is designated the X-axis and that in the transport position is designated as the Y-axis, then the tractorend point of articulation will lie in or close to the Xor Y-axis of symmetry. The drawbar as such may be

Claims

1. Apparatus for cultivating soil in agriculture and which, with a considerable working width, can be transported in a longitudinal direction on separate wheels and which has a drawbar (2) for the purpose, characterised in that the drawbar (2) is constructed to be pivotable from the working into the transport position and vice versa, the straight line (9, 9') or the extension thereof which is formed by the real or ideal drawbar articulation points (9) at the tractor end and implement end respectively does not intersect with the centre of gravity or resistance point (8) of the implement (1).

2. Apparatus according to Claim 1, characterised in that the drawbar (2) is constructed to be independently lockable in the extreme positions.

3. Apparatus according to Claim 1, characterised in that on the frame (3) the drawbar (2) is disposed in locking bolts (12,13) which establish the extreme positions.

4. Apparatus according to Claim 3, characterised in that releasing means operable from the tractor are associated with the locking bolts (12, 13).

5. Apparatus according to Claim 1 and Claim 2, characterised in that the drawbar (2) is equipped with an articulating linkage (10) for the bottom links of the tractor.

6. Apparatus according to Claim 1, characterised in that the wheels (4, 5) are constructed to be pivotable.

7. Apparatus according to Claim 1, characterised in that hydraulic operating cylinders are associated with the wheels (4, 5).

8. Apparatus according to Claim 1, characterised in that the tractor-end articulation point (11) in the relevant extreme position lies approximately in the axis of symmetry (14,15) of the implement (1 ) in the working position or the transport position.

9. Apparatus for cultivating soil as claimed in claim 1, substantially as described herein with reference to and as illustrated by the accompanying drawings.