IMPROVEMENTS IN OR RELATING TO HITCHING

Abstract

A vehicle-to-implement hitch is provided and comprises a force transfer hitch connector adapted to provide a hitch point to which an implement can be connected. The connector is couplable to the vehicle by one or more flexible tensioning members which are, or can be moved so as to be, taut whereby to create a rigid structure comprising a hitch location such that the hitch point is movable.

Claims

1. A vehicle-to-implement hitch comprising a force transfer hitch connector adapted to provide a hitch point to which an implement can be connected, wherein the hitch is movable between a stowed configuration and a deployed configuration and is deployable from a vehicle in use, wherein the connector is couplable to the vehicle by two or more flexible tensioning members which are relaxed in the stowed configuration and taut in the deployed position and which create a pseudo-rigid structure in the deployed configuration comprising a hitch location such that the hitch point is movable, whereby the pseudo-rigid structure provides for a controlled over-load reaction from which the structure can recover without damage.

2.-5. (canceled)

6. The hitch according to claim 1, in which the connector is a boom.

7. The hitch according to claim 1, in which the hitch location is real.

8. The hitch a according to claim 1, in which the hitch location is a pivot point that is part of a linkage that forms a virtual hitch point.

9. The hitch according to claim 1, in which the connector is in advance of the hitch location.

10. The hitch according to claim 1, in which the connector is part of the hitch point.

11. The hitch according to claim 1, further comprising one or more actuators for moving the hitch from the stowed to the deployed configuration.

12. The hitch according to claim 11, in which the or each actuator is pre-charged and stored energised and/or in which the or each actuator is connected or connectable to an external power source.

13.-14. (canceled)

15. The hitch according to claim 1, comprising a plurality of actuators in which actuators deploy in sequence or actuators deploy simultaneously.

16.-17. (canceled)

18. The hitch according to claim 1, in which in the deployed position tensioning members assume a triangular configuration with the hitch point formed at an apex thereof.

19. The hitch according to claim 1, in which at least one of the two or more tensioning members is a cable, rope, strap, cord, or chain.

20. The hitch according to claim 19, in which the tensioning member is a wire rope.

21. The hitch according to claim 19, in which excess length of the cable, rope, strap, cord, or chain is controlled to ensure they pack neatly.

22. The hitch according to claim 1, further comprising means for locking the mechanism, or parts of the mechanism, into the stowed position.

23. The hitch according to claim 1, consisting of two or three tautable tensioning members.

24. The hitch according to claim 1, formed as a 2D mechanism.

25. The hitch according to claim 1, formed as a 3D mechanism.

26. A hitch mechanism comprising a deployable structure which is deployed from a compact, stowed configuration using actuators and flexible members which becomes rigid when tensioned and create a hitch location in which the resulting structure is able to collapse if hits an obstacle and then re-form after passing the obstacle.

27.-29. (canceled)

30. A mine clearance system comprising a vehicle-to-implement hitch according to claim 1 and a surface clearance implement connected to the vehicle via the hitch.

Description

[0062] The present invention is more particularly shown and described, by way of example, in the accompanying drawings, in which:

[0063] FIGS. 1 to 7hitch point information and discussion.

[0064] FIG. 8the hitch point deployment structure in a stowed position.

[0065] FIG. 9the deployment structure in a deployed position.

[0066] FIG. 10the hitch point in an intermediate position.

[0067] FIG. 11the deployment structure in the fully deployed position.

[0068] FIG. 12the deployment structure as if an overload force has been applied to the front of the boom.

[0069] FIG. 13the deployment structure as if the boom strikes an immovable object and the hitch point deflects upwards, or in any other direction.

[0070] FIG. 14 and FIG. 15stowed and deployed positions of a hitch formed according to a further embodiment.

[0071] FIG. 16illustrate that if the structure of FIG. 15 is overloaded from excessive draught force it can deflect rearwards and can be made to recover the original position.

[0072] FIG. 17illustrates that if the structure of FIG. 15 strikes an immovable object, such as debris or extreme undulations in the ground surface, the structure is able to deflect upwards, or in any other direction and can be made to recover the original position.

[0073] FIG. 18a 2D system comprising one actuator and two ropes.

[0074] FIGS. 19 to 22a 3D system comprising three tautable ropes.

[0075] The example embodiments are described in sufficient detail to enable those of ordinary skill in the art to embody and implement the systems and processes herein described. It is important to understand that embodiments can be provided in many alternative forms and should not be construed as limited to the examples set forth herein.

[0076] Accordingly, while embodiments can be modified in various ways and take on various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. There is no intent to limit to the particular forms disclosed. On the contrary, all modifications, equivalents, and alternatives falling within the scope of the appended claims should be included. Elements of the example embodiments are consistently denoted by the same reference numerals throughout the drawings and detailed description where appropriate.

[0077] Unless otherwise defined, all terms (including technical and scientific terms) used herein are to be interpreted as is customary in the art. It will be further understood that terms in common usage should also be interpreted as is customary in the relevant art and not in an idealised or overly formal sense unless expressly so defined herein.

[0078] In the description, all orientational terms, such as upper, lower, radially and axially, are used in relation to the drawings and should not be interpreted as limiting on the invention.

[0079] FIG. 1: A simple Real Hitch Point where a boom (A) is directly attached to a vehicle (B) with a rigid connection (C), shown in the working position, with a tool (not shown) lowered to the ground. It is simple and lightweight but the angle of the boom directs the weight of the vehicle in to the tool and when subject to a large draught force the tool will be pressed in to the ground with greater force.

[0080] FIG. 2: The Real Hitch Point is also limited by the stowed position. The tool can be raised from the ground but the equipment cannot be returned to a compact stowed position in such a simple implementation.

[0081] FIG. 3: A Real Hitch Point can be improved by moving the connection point (D) lower to the ground. This limits the undesirable force increase and ground pressure, when subjected to a large draught force. The undesirable consequence of the low connection point is a reduction in ground clearance.

[0082] FIG. 4: This simple implementation has a similar limitation on the compactness of the stowed position. The tool can be raised but compact stowage is not possible.

[0083] All of these hitch points may allow the tool to pivot freely and contour the ground, the tool may be rigidly attached to the boom, in which case the tool will rotate with the boom, or the tool may pivot on the end of the boom and be controlled by an additional actuator.

[0084] FIG. 5/6: A further development of a low hitch point could be the 3-point hitch or a virtual hitch point where an additional, upper boom (E) is added, which is also pivotably connected to the tool. This control the pitch angle of the tool but also directs the forces through a point (represented in the figure) by the meeting of the dashed lines. This allows the draught forces subjected to the tool and the vehicle to be carefully controlled. The location of the hitch point will move slightly through the working position of the tool.

[0085] FIG. 7: The 3-point hitch is still limited in how much it can be compactly stowed.

[0086] FIGS. 8 to 11 illustrate a hitch mechanism (10) formed in accordance with the present invention and shown coupled to a host vehicle 2 in a stowed (FIG. 8), intermediate (FIG. 10) deployed (FIGS. 9 and 11) position.

[0087] The hitch mechanism is initially stowed up close to the host vehicle (FIG. 8). Actuators (3) and (4) are compressed. These may be pre-charged and stored energized or may be connected to an external power source. Ropes (5) and (6) and actuator (4) connect the rear of the boom (1) to the vehicle (2) in a forward and rearward position. The ropes are essentially slack in the stowed position but their excess length may be controlled by additional weak springs or weak restraints to ensure they pack neatly.

[0088] A facility to lock the mechanism, or parts of the mechanism, into the stowed position may or may not be required/provided.

[0089] When the system is released, actuator (4) is commanded to move and extends (FIG. 10); the mechanism starts to deploy (FIG. 10). This moves the rear end of the boom (1) to a low, stable position about which the boom can pivot during operations; a real hitch point (RHP) has been formed.

[0090] Latterly, the second actuator (3) is commanded to move. This lowers the boom (1) and any attached ground-clearing tools or other equipment to the ground (FIG. 11). In the case of ground clearing tools it can applied a near-constant pushdown force, while able to contour the ground.

[0091] In some ways this arrangement can be thought of as a pin-jointed triangle. The ropes are only capable of transmitting tension and the actuator (4) serves as a strut between them, connecting common ends of the ropes at an apex which then creates the hitch point in space.

[0092] The use of ropes, wires or the like and actuators allows a simple system using a real hitch point in the ideal location to be generated, where the forces subjected to equipment and vehicle and minimized.

[0093] The use of ropes, wires or the like and actuators allows the rigid structure to be collapsed for compact stowage.

[0094] There may be multiple sets of this 2-dimensional mechanism across the width of the vehicle.

[0095] If the structure is overloaded from excessive draught force, the structure can deflect rearwards (see FIG. 12) and can be made to recover the original position.

[0096] If the structure strikes an immovable object, such as debris or extreme undulations in the ground surface, the structure is able to deflect upwards, or in any other direction (see FIG. 13) and can be made to recover the original position.

[0097] FIG. 14 and FIG. 15 show stowed and deployed positions of a hitch formed according to a further embodiment. The hitch point actuator and ropes are shown. FIG. 15 illustrates the generation of the hitch point using the actuator and the ropes.

[0098] The hitch point is a point in the generally triangular linkage. It could be considered as a real hitch point, but it is movable in the event of an overloadsee below.

[0099] If the structure is overloaded from excessive draught force, the structure can deflect rearwards (see FIG. 16) and can be made to recover the original position.

[0100] If the structure strikes an immovable object, such as debris or extreme undulations in the ground surface, the structure is able to deflect upwards, or in any other direction (see FIG. 17) and can be made to recover the original position.

[0101] A simple 2D system is illustrated in FIG. 18 comprising one actuator and two ropes, assumed to act in a plane. The two rope radii (R1 and R2) are marked. The hitch point when fully deployed is at the vertex. If one rope is slack then the hitch point will move along one edge. If both ropes are slack the hitch location (e.g., hitch point) will be located inside the hatched area. Note the similarities between FIG. 18 and FIG. 15.

[0102] Referring now to FIGS. 19 to 22 a generic 3D embodiment is shown, including three taut cables from three corners of the rectangular plate (the vehicle front) individually create three spherical surfaces and the hitch point is able to move within the common volume of these three spheres, i.e., the hitch moves over the surfaces show when two of the cables are slack and one taut. It moves along the lines where two surfaces interest when one cable is slack. And the hitch point is at the point where the three surfaces meet when all the cables are taut. When all three cables are slack, the hitch location is somewhere inside this surface envelope.

[0103] FIG. 19 illustrates an assembly of three ropes and an actuator to tension them.

[0104] FIG. 20 illustrates a 3D shape envelope showing possible positions of hitch point, should the actuator be overloaded and rope/s become slack. FIG. 21 further draws attention to the radius of each face, which is generated by a rope.

[0105] In FIG. 22 the key points of the shape are labelled, explaining the possible positions of hitch location: [0106] a. If the actuator is fully extended then all ropes are taut and the hitch location is located at the vertex [0107] b. If the actuator is overloaded and is no longer fully extended the hitch point location is undefined: [0108] i. If one rope is slack then the hitch point is located along one edge (n.b. there are three edges on the diagram) [0109] ii. If two ropes are slack then the hitch point is located one face (n.b. there are three faces on the diagram) [0110] iii. If all ropes are slack then the hitch point is located inside the volume.

[0111] Although illustrative embodiments of the invention have been disclosed in detail herein, with reference to the accompanying drawings, it is understood that the invention is not limited to the precise embodiments shown and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope of the invention as defined by the appended claims and their equivalents.