Steering arrangement for an off-highway articulated vehicle

• US 4,453,614 A
• Filed: 03/19/1982
• Issued: 06/12/1984
• Est. Priority Date: 03/19/1982
• Status: Expired due to Fees

• Current Assignee: Deere & Company
• Original Assignee: Deere & Company
• Inventors: Allen, James R., Myers, Christopher A.
• Primary Examiner(s): Pekar, John A.
• Application Number:
  US06/360,022
• Time in Patent Office: 816 Days
• Field of Search: 180/139, 180/235, 180/236, 180/237, 180/238, 180/14 R
• US Class Current: 180/420
• CPC Class Codes: A01D 67/00 Undercarriages or frames specially adapted for harvesters or mowers coupling arrangements between animal or tractor and harvester or mower A01B59/00; Mechanisms for adjusting the frame adjusting devices for the cutter-bar A01D34/28; Platforms
• CPC Class Codes: B62D 53/02 comprising a uniaxle tractor unit and a uniaxle trailer unit see B60B11/00 - B60B11/08

Abstract

In an articulated combine, front and rear bogies are connected by spaced-apart upper and lower links. The upper link permits relative lateral movement between the bogies due to oscillation about a longitudinal axis. At the lower link, a rigid tongue of the rear bogie is connected to the front bogie by a ball hitch. Steering of the vehicle is through a pair of hydraulic cylinders controlled in part by a feedback cylinder. The steering cylinders are connected together to the rear bogie, at a common ball joint. All other connections of the hydraulic cylinders are ball and socket type and their effective pivot centers define respective transverse (kneel) and longitudinal (oscillation) axes, intersecting at the ball hitch. Forward connections of the steering cylinders and one end of the feedback cylinder lie on the kneel axis. The common rearward steering cylinder connection and the connection of the other end of the feedback cylinder lie on the oscillation axis. This arrangement isolates the steering system from oscillation and tipping movement of one bogie relative to the other in the sense that such movement, by itself, does not directly impose length changes or axial loading in the steering system cylinders.

Claims

1. An off-highway articulated vehicle for traversing an uneven ground surface comprising:

front and rear bogies, each having at least one pair of laterally spaced wheels for supporting the bogie above the ground surface;

means, including a hitch pivot, for pivotally connecting the rear bogie to the front bogie so that relative movement may take place between the bogies, including pivoting about an upright axis passing through the hitch pivot for steering the vehicle and oscillation about a generally fore-and-aft oscillation axis for conforming the vehicle to the uneven surface; and

power means for effecting the pivoting about the upright axis, including first and second hydraulic cylinders each having a first end pivotally connected to the front bogie, at opposite sides of the hitch pivot respectively, and a second end pivotally connected to the rear bogie so that the respective longitudinal axes of the hydraulic cylinders intersect at and share a common pivot center positionally fixed with respect to the rear bogie, the connections of the hydraulic cylinders to the rear bogie including universal pivot means for defining the common pivot center and effective to permit oscillation of the rear bogie relative to the front bogie without disturbing the spatial relationship of the first cylinder to the second cylinder so that said oscillation does not distort the steering effect of the cylinders.

2. The articulated vehicle of claim 1 wherein the means for pivotally connecting the rear bogie to the front bogie comprises a lower portion including the hitch pivot, said pivot providing a universal pivot connection defining a hitch pivot center, and an upper portion spaced upward from the lower portion, said upper portion permitting relative lateral displacement between at least the upper portions of the respective bogies and wherein the connections of the hydraulic cylinders to the front bogie include universal pivot means, each of said means defining a pivot center and said centers being in common transverse alignment with the hitch pivot center and defining a kneel axis so that relative pivoting of the bogies may take place about the kneel axis with no influence on steering cylinder length.

3. The articulated vehicle of claim 2 wherein the upper portion of the means for connecting the bogies includes a normally fore-and-aft link extending between and pivotally connected at its opposite ends to the front and rear bogies respectively.

4. The articulated vehicle of claim 2 and further including a feedback hydraulic cylinder and universal pivot means for connecting the opposite ends of said cylinder respectively to the front and rear bogies, said connections defining pivot centers and said centers being spaced from the hitch pivot center and lying on the oscillation and kneel axes respectively.

5. The articulated vehicle of claim 1 wherein the connection of the hydraulic steering cylinders to the rear bogie is below that of their connection to the front bogie so that the plane defined by the longitudinal axes of the hydraulic cylinders is inclined rearwardly and downwardly.

6. The articulated vehicle of claim 5 wherein the plane defined by the axes of the hydraulic steering cylinders intersects the wheels of the rear bogie adjacent their contact point with the ground surface.

7. The articulated vehicle of claim 1 wherein the universal pivot means includes:

a pivot member carried in fixed positional relationship to the rear bogie, said member having external surfaces including a spherical surface portion having a center defining the common pivot center;

a first annular member carried by the second end of the first hydraulic cylinder having a bore perpendicular to the cylinder longitudinal axis;

a second annular member carried by the second end of the second hydraulic cylinder having a bore perpendicular to the cylinder longitudinal axis; and

adapter means for retaining the bores of the annular members in coaxial alignment and in a universal pivoting relationship with the common pivot center.

8. An off-highway articulated vehicle comprising:

a forward mobile unit supported above the ground on laterally spaced wheels and having a rearward hitch element;

a rear mobile unit supported above the ground on laterally spaced wheels and having a forward hitch element;

means for connecting together the respective hitch elements of the front and rear mobile units, said means defining a hitch pivot center and permitting at least limited relative motion between said mobile units, pivoting about said center including pivoting about an upright axis and oscillation between the units;

first and second rear steering cylinder connecting elements carried by the rear mobile unit and at least partially defining a common universal steering cylinder pivot center disposed so that a line passing through said steering cylinder pivot center and said hitch pivot center lies in a generally fore-and-aft vertical plane of the rear mobile unit and defines an oscillation axis for said unit, the second rear steering cylinder connecting element being operatively associated with the first rear steering cylinder connecting element and disposed so as to be universally pivotable about said rear steering cylinder universal pivot center and so define the common pivot center;

first and second steering cylinder forward connecting elements carried by the forward mobile unit, each at least partially defining a pivot axis laterally spaced from and, respectively, on opposite sides of the hitch pivot center; and

first and second steering cylinders connected between the respective forward and rear steering cylinder connecting elements, the longitudinal axes of the two cylinders intersecting at the common pivot center of the rear mobile unit, and said cylinders being operable to extend and retract so as to slew the rear unit with respect to the front unit, said pivot connections of the steering cylinders to the rear mobile unit unit and of the hitch permitting relative oscillation between the mobile units about the oscillation axis, without modifying the steering effect of the steering cylinder.

9. A steering arrangement for an off-highway articulated vehicle having first and second bogies coupled together so as to permit at least limited universal pivoting between the bogies about a hitch pivot center, and a pair of hydraulic cyliders each having a longitudinal axis and a first end connected to the first bogie and a second end connected to the second bogie said connections defining cylinder pivot centers characterized in that the cylinder longitudinal axes and the hitch pivot center all lie in the same plane and that the pivot centers of the cylinder first ends are disposed one on each side of the hitch pivot center and in lateral alignment with it and that the cylinder longitudinal axes intersect at a point of intersection and the respective pivot centers of the cylinder second ends coincide with said point of intersection.

10. An articulated combine comprising:

a forward bogie including crop gathering and processing means;

a rear bogie incuding crop handling means;

a hitch connecting the front and rear bogies towards their lower portions and defining a hitch pivot center for limited relative universal pivoting motion including oscillation between the bogies;

a pair of hydraulic steering cylinders each having first and second ends;

a pair of means for connecting the first ends of the steering cylinders to the forward bogie including pivot connections defining pivot centers on opposite sides of and in lateral alignment with the pivot center of the hitch; and

universal pivot means for connecting together the second ends of the hydraulic cylinders to the rear bogie and defining a single universal pivot center so that the lines of action of the cylinders pass through said center.

11. The articulated combine of claim 10 and further including a stabilizing link pivotally connected between the respective bogies towards their upper portions and disposed generally above the hitch.