GB2238455A

GB2238455A - Lateral movement limiting system

Info

Publication number: GB2238455A
Application number: GB9023778A
Authority: GB
Inventors: Risto Kakela; Rauno Ollila
Original assignee: YLOE TEHTAAT Oy
Current assignee: YLOE TEHTAAT Oy
Priority date: 1989-12-01
Filing date: 1990-11-01
Publication date: 1991-06-05
Also published as: DE4036375A1; FI83016B; FR2655233A1; FI83016C; FI895771A0; GB9023778D0

Abstract

In a lateral movement limiting system in connection with pull rods (1), mounted on a tractor wherein a hydraulic cylinder (2) is provided between each pull rod (1) and a tractor chassis (R), a pressure-medium tank (5) and a means (6) for carrying the pressure medium between the cylinders (2) and the pressure-medium tank are located in the cabin of the tractor or in the immediate vicinity thereof to be controlled from the cabin. Cylinders (2) are both linked with hoses (3) or similar means to be in communication with pressure-medium tank (5) and said hoses (3) or similar means are each fitted with a valve member (7) to be controlled from the cabin for regulating a pressure-medium flow rate between pressure-medium tank (5) and the appropriate cylinder (2). <IMAGE>

Description

1 Lateral movement limiting system The present invention relates to a

lateral movement limiting system for the three-point linkage of a tractor or a like working machine, as defined in more detail in the preamble of claim 1.

An essential feature in the operation of a three-point tractor linkage is that a working machine connected therewith is capable of lateral movement. This is necessary even in view of connecting the machine.

In certain types of work, however, this causes trouble and, thus, various devices have been developed for the pull rods in order to stop this lateral movement whenever necessary. Such prior known devices include chain limiters and telescopic limiters, capable of controling the movement. A further developed lateral movement limiter is a hydraulic lateral movement limiter, each limiter being separately provided with an adjusting device and a back-up tank.

A common drawback to all of the above lateral movement limiters is that the adjustment of said lateral movement limiter is carried out immediately adjacent to the lateral movement limiter and that is often quite cramped and dirty spot. In addition, the operator must climb out of the control cabin for an adjustment.

Furthermore, the prior known lateral movement limiters are passive, i.e. not capable of moving the pull rods but only of preventing or allowing the movement thereof.

An object of a lateral movement limiting system according to this invention is to eliminate the above drawbacks. The lateral movement limiting system is opera- 2 tionally active and easy to operate. It can be used to move the pull rods as desired at the time of linking. In addition, all actions are controllable directly from the cabin of a tractor. Thus, the novel invention substantially raises the available prior art.

In order to achieve this object, the invention is mainly characterized by what is set forth in the characterizing clause of the annexed claim.

The invention is described in more detail in the following specification and accompanying drawing, showing a perspective view of one possible embodiment of the invention mounted in connection with the three-point linkages of a tractor shown by thinned-out lines.

Between a tractor chassis R and pull rods 1 are mounted single-action spring-controlled hydraulic cylinders, serving as lateral movement limiters 2 and both connected with hoses 3 to a control centre 4 located in a tractor's cabin TO or in the immediate vicinity thereof, said control centre being fitted with a separate valve 7 for each lateral movement limiter 2. The particular valve 7 can used either for closing or opening a communication between the appropriate lateral movement limiter 2 and a tank 5 as well as for adjusting the communication to such a throttled position that the movement of lateral movement limiters 2 will be effectively deadened. A hand pump 6 or a like device can be used for moving said pull rods 1. According to the position of valves 7, the movement proceeds either to one or each lateral movement limiter 2.

In a driving situation, it is thus possible directly from a tractor's cabin TO either to manually lock said i.

X 3 lateral movement limiters 2 or respectively to permit lateral oscillation in the open position. Likewise, it is possible to select a dampened movement in order not to break the working machine e.g. in bends and collisions but, instead, the working machine will be able to assume a proper operating position after a while. This is important when working e. g. on a planting furrow.

The lateral movement limiters 2 can be designed as single-action devices by fitting therein a spring member which acts in a manner that the pull rod 1 in question returns to its outermost position whenever the locking of the respective lateral movement limiter is released.

In a linking situation, the active lateral movement limiters 2 offer a major advantage whenever the tractor is provided with quick-coupling clamps. Thus, such lateral movement limiters 2 can be used for setting pull rods 1 in a proper position prior to coupling.

4

Claims

1. A lateral movement limiting system in connection with pull rods (1), mounted on a tractor or a like working machine and particularly included in three-point linkages, said lateral movement limiting system comprising a pressure-medium filled lateral movement limiter (2), especially a hydraulic cylinder between each pull rod (1) and a tractor chassis (R), a pressure-medium tank (5) and a means (6) for carrying the pressure medium between said lateral movement limiters (2) and the pressure-medium tank, c h a r a c t e r i z e d in that said pressure-medium tank (5) included in the lateral movement limiting system and said means (6) for carrying the pressure medium are located in the cabin of a tractor or a like working machine or in the immediate vicinity thereof to be controlled from the cabin, that said lateral movement limiters (2) are both linked with hoses (3) or similar means into communication with pressure-medium tank (5), and that said hoses (3) or similar means are each fitted with a valve member (7) located in the cabin or in the immediate vicinity thereof to be controlled from the cabin for regulating a pressure-medium flow rate between pressure-medium tank (5) and the appropriate lateral movement limiter (2).

2. A lateral movement limiting system as set forth in claim 1, character i zed inthatsaidmeans (6) for carrying a pressure medium comprises a hand PUMP.

3. A lateral movement limiting system as set forth in claim 1, c h a r a c t e r i z e d in that said lateral movement limiter (2) is accompanied by a spring member fl t -1 1 or a like, said spring member or a like being adapted to return the appropriate pull rod (1) to its outermost position after releasing the locking.of lateral movement limiter (2).

4. A lateral movement limiting system substantially as hereinbefore described with reference to the accompanying drawing.

Published 1991 at Tbe Patent Ofte. State HOuse-66/71 High Holbom. U)ndonWCIR47?. Further copies maybe obtained from we linfach. Cross Kcvs. Newport NP I 7HZ. Printed by Multiplex techniques ltd. St Mary Cray. Kent.

s Branch. Unit 6, Nine Mile Point Cwrnk