Front implement control

• US 6,343,660 B1
• Filed: 09/25/2000
• Issued: 02/05/2002
• Est. Priority Date: 03/26/1998
• Status: Expired due to Fees

• Current Assignee: Franciscus Hubertus Mutsaers
• Original Assignee: Franciscus Hubertus Mutsaers
• Inventors: Mutsaers, Franciscus Hubertus
• Primary Examiner(s): PEZZUTO, ROBERT ERIC
• Application Number:
  US09/669,078
• Time in Patent Office: 498 Days
• Field of Search: 172/273, 172/274, 172/280, 172/307, 172/811, 172/813, 172/817, 172/810, 172/373, 172/826
• US Class Current: 172/273
• CPC Class Codes: A01B 59/048 having pulling or pushing means arranged on the front part of the tractor

Abstract

A steering gear for controlling an implement suspended in front of a tractor, with a yoke structure for coupling to a tractor, a steerable part, and at least two transmission structures, spaced apart in transverse direction, between the steerable part and the yoke structure and engaging the steerable part in laterally spaced apart engagement positions. If the steerable part is moved to the left, it is steered rightwards by the transmission structures and vice versa by displacing the steerable part forward at one engagement position. At the other engagement position rearwards displacement, if any, is at least immediately or within a specific lateral movement path, limited to displacement substantially smaller than the forward displacement at the other engagement position. Thus, an accurate course of the implement along an intended processing path is obtained.

Claims

1. A steering gear for controlling an implement in a coupling between a tractor and said implement mounted in front of the tractor, comprising:

a yoke structure for coupling to the tractor,

a part which is steerable relative to the yoke structure, and

at least two transmission structures between the steerable part and the yoke structure, said transmission structures, in a straight-on position, being spaced apart at least in a horizontal direction transverse to a processing direction and which define engagement positions for exerting forces having at least one component in the processing direction on the steerable part and are arranged for allowing lateral movement of the steerable part from a straight-on position to the left and to the right relative to the yoke structure, and, when the steerable part moves to the left, for urging the steerable part forwards relative to the yoke structure at the left one of said engagement positions, causing it to steer to the right, and, when the steerable part moves to the right, for urging the steerable part forwards relative to the yoke structure at the right one of said engagement positions, causing it to steer to the left,

wherein the transmission structures are of such design that during a lateral movement of the steerable part within at least a specific path, wherein the steerable part at said one of said engagement positions moves forwards, any rearward movement of the steerable part at the other one of said engagement positions, relative to the yoke structure is limited to movement with a substantially constant ratio relative to the lateral movement and continuously by a distance less than the forward displacement at said one of the engagement positions, in the processing direction or against the processing direction.

2. A steering gear for controlling an implement in a coupling between a tractor and said implement mounted in front of the tractor, comprising:

a yoke structure for coupling to the tractor,

a part which is steerable relative to the yoke, and

at least two transmission structures between the steerable part and the yoke structure, said transmission structures, in a straight-on position, being spaced apart at least in a horizontal direction transverse to a processing direction and which define engagement positions for exerting forces having at least one component in the processing direction on the steerable part and are arranged for allowing lateral movement of the steerable part from a straight-on position to the left and to the right relative to the yoke structure, and, when the steerable part moves to the left, for urging the steerable part forwards relative to the yoke structure at the left one of said engagement positions, causing it to steer to the right, and, when the steerable part moves to the right, for urging the steerable part forwards relative to the yoke structure at the right one of said engagement positions, causing it to steer to the left,

wherein the transmission structures are of such design that during a lateral movement of the steerable part and an associated forward displacement of the steerable part at said one of said engagement positions, any rearward movement of the steerable part at the other one of said engagement positions, relative to the yoke structure is limited to movement which is immediately by a distance less than the forward displacement at said one of the engagement positions.

3. A gear according to claim 2, wherein the transmission structures are of such design that during a lateral movement of the steerable part relative to the yoke structure, the steerable part pivots relative to the yoke structure about a point in the area of said other one of said transmission structures.

4. A gear according to claim 2, wherein in said straight-on position, the forces exerted on the steerable part are directed substantially parallel to said processing direction.

5. A gear according to claim 2, wherein in said straight-on position, said engagement positions on at least one side act on a surface oriented substantially at right angles to said processing direction.

6. A gear according to claim 2, wherein said transmission structures each contain at least one guideway and a guide element that is displaceable along said guideway according to an at least locally curved path, wherein, starting from said straight-on position, the angle of said path relative to said processing direction on one side of the associated guide element is in each case smaller than on the other side of the guide element.

7. A gear according to claim 6, wherein said guideways are arranged symmetrically and at a distance from each other on either side of a vertical central longitudinal plane which is directed in said processing direction.

8. A gear according to claim 6, wherein said guideways extend horizontally.

9. A gear according to claim 6, wherein said guideways are profiled and said guide elements, viewed in section transversely to said guideways, have a contour that corresponds to said profile.

10. A gear according to claim 6, wherein said guide elements are provided with rollers.

11. A gear according to claim 10, wherein said guideways and said rollers have enmeshing teeth.

12. A gear according to claim 10, wherein the positions of said rollers are adjustable for adjusting the mutual distance between the rollers.

13. A gear according to claim 10, wherein each of said guide elements is formed by at least two rollers suspended in a roller support, wherein the rotation axes of said rollers are in each case located on either side of pivotal axes of said roller supports.

14. A gear according to claim 13, wherein the distance between two rollers supported by the same roller support is adjustable.

15. A gear according to claim 6, wherein said steerable part is provided with said guideways and wherein said guide elements are supported by said yoke structure.

16. A gear according to claim 6, wherein said yoke structure is provided with said guideways and wherein said guide elements are supported by said steerable element.

17. A gear according to claim 6, wherein said guideways contain straight sections, and wherein in said straight-on position, said engagement positions are located in the area of said straight sections, and wherein said straight sections are directed transversely to said processing direction and blend with curved sections of said guideways.

18. A gear according to claim 6, wherein the position and orientation of said guideways are adjustable.

19. A gear according to claim 6, wherein the mutual distance between said guide elements is adjustable.

20. A gear according to claim 2, wherein said transmission structures each comprise a pivotable body, said pivotable bodies being mounted for pivoting about substantially vertical axes between the yoke structure and the steerable part such that during a lateral movement of the steerable part relative to the yoke structure, one of said pivotable bodies urges the steerable part forwards relative to the yoke structure and the other one of said pivotable bodies causes the steerable part, relative to the yoke structure, substantially not to move rearwards or at least to move rearwards immediately and by a distance less than the forward displacement caused by said one of said pivotable bodies.

21. A gear according to claim 2, wherein said transmission structures each comprise a pivotable body, said pivotable bodies being mounted for pivoting about substantially vertical axes between the yoke structure and the steerable part such that at least during a lateral movement of the steerable part relative to the yoke structure within a specific path, wherein said one of said pivotable bodies urges the steerable part forwards relative to the yoke structure, the other one of said pivotable bodies causes the steerable part, relative to the yoke structure, substantially not to move rearwards or at the most to move rearwards with a substantially constant ratio relative to the lateral movement and continuously less than the forward displacement caused by said one of said pivotable bodies.

22. A gear according to claim 20, wherein the pivotable bodies are each designed as a tumbler body suspended for pivoting about an axis relative to the yoke structure or the pivotable part, further comprising:

supports that can pivot along with the tumbler bodies and that engage the steerable part or the yoke structure respectively, carriers for causing the tumbler bodies to swivel in reaction to lateral movement of the steerable part, and means for limiting lateral displacements of the steerable part relative to rearward displacements of supports that can swivel along with the tumbler bodies from the straight-on position.

23. A gear according to claim 20, wherein the pivotable bodies are designed as rockers, wherein one end of each of the rockers is displaceable from the straight-on position in lateral direction along the yoke structure or the steerable part, further comprising stops for limiting said lateral displaceability, said stops being of such design that each of said rockers, during lateral movements of the steerable part relative to the yoke structure, swivels along if the steerable part at that rocker moves away from a central longitudinal plane directed in said processing direction and pivots along less or not at all if the steerable part at that rocker moves towards said central longitudinal plane.

24. A gear according to claim 23, wherein the rockers are laterally displaceable along the steerable part and wherein the stops are located between said central longitudinal plane and said rockers.

25. A gear according to claim 23, wherein the rockers are laterally displaceable along the yoke structure and wherein the stops are located on the sides of said rockers remote from said central longitudinal plane.

26. A gear according to claim 23, wherein said stops for limiting said lateral displaceability of the rockers are displaceable from the straight-on position in lateral direction for adjusting the extent to which lateral displaceability of the rockers from the straight-on position in lateral direction is limited.

27. A gear according to claim 23, wherein the rockers are each provided with at least a first and a second abutment surface for abutment against the steerable part or the yoke structure, wherein the first of said abutment surfaces abuts against the steerable part or the yoke structure if the rocker is in the straight-on position and wherein the second one of said abutment surfaces abuts against the steerable part or the yoke structure if the rocker is in the swiveled-out position and, viewed in processing direction, is located closer to the pivotal axis of the relevant rocker than the first one of said abutment surfaces of the same rocker, for enhancing the forwardly urging action of the swiveled-out rocker.

28. A gear according to claim 2, further comprising means for exerting, over a work path, a force that supports a displacement of the steerable part in the processing direction.

29. A gear according to claim 28, wherein said means for exerting a force over a work path are mounted between at least one of said transmission structures and the yoke structure.

30. A gear according to claim 28, wherein said at least one transmission structure comprises a pivotable body for urging the steerable part in processing direction in reaction to pivoting movements of said body, wherein said pivotable body is connected to the steerable part and the yoke for pivoting from the straight-on position, operated by lateral movements of the steerable part relative to the yoke, to exclusively one side relative to the straight-on position of the steerable part.

31. A gear according to claim 30, wherein the connection between the steerable part and the pivotable part is formed by a connection designed for exclusively transmitting pulling forces.

32. A gear according to claim 28, wherein the means for exerting a force over a work path comprise an elastic element.

33. A gear according to claim 28, wherein the means for exerting a force over a work path, in condition of use, are biased in the straight-on position.