REAR CARRIAGE STEERING MECHANISM AND METHOD

Abstract

A method of adjusting a steering mechanism of a front axle of a rear carriage of a multi-part wheeled articulated vehicle includes the step of adjusting the steering mechanism to a setting corresponding to a target value of the steering deflection angle of the wheels of the front axle of the at least one rear carriage and modifying the steering deflection angle such that forces and/or moments and resulting displacements and/or torsions and/or tensions acting on the front and/or rear carriages are minimized.

Claims

1. A method of adjusting a steering mechanism of a front axle of a rear carriage of a multi-part wheeled articulated vehicle, comprising the steps of: providing a multi-part wheeled articulated vehicle having a front carriage and at least one rear carriage articulately joined with the front carriage, the at least one rear carriage having at least a front axle and a rear axle, each having wheels, at least the wheels of the front axle of the at least one rear carriage being steerable, the front carriage including at least one steerable axle having wheels; providing a steering mechanism for the front axle of the at least one rear carriage, the steering mechanism operable to adjust a steering deflection angle of the wheels of the front axle of the rear carriage; adjusting the steering mechanism to adjust the steering deflection angle of the wheels of the front axle of the at least one rear carriage when the vehicle drives around a bend such that the respective rear carriage follows the front carriage, the adjusting step comprising adjusting the steering mechanism to a setting corresponding to a target value of the steering deflection angle of the wheels of the front axle of the at least one rear carriage; and modifying the steering deflection angle of the wheels of the front axle of the at least one rear carriage when the vehicle drives around a bend such that forces and/or moments and resulting displacements and/or torsions and/or tensions acting on the front and/or rear carriages are approximately minimized.

2. A method in accordance with claim 1, further comprising calculating the target value of the steering deflection angle of the wheels of the front axle of the at least one rear carriage based on a steering deflection angle of the wheels of the at least one steerable axle of the front carriage.

3. A method in accordance with claim 2, wherein the wheels of the rear axle of the at least one rear carriage are steerable, the calculating step further comprising calculating the target value based a steering deflection angle of the wheels of the rear axle of the at least one rear carriage.

4. A method in accordance with claim 1, further comprising calculating the target value of the steering deflection angle of the wheels of the front axle of the at least one rear carriage based on an angle between a longitudinal axis of the front carriage and a longitudinal axis of the at least one rear carriage.

5. A method in accordance with claim 4, wherein the wheels of the rear axle of the at least one rear carriage are steerable, the calculating step further comprising calculating the target value based a steering deflection angle of the wheels of the rear axle of the at least one rear carriage.

6. A method in accordance with claim 1, wherein the steering mechanism comprises a computer unit.

7. A method in accordance with claim 1, further comprising sensors adapted to determine the forces and/or moments, displacements, torsions and/or tensions.

8. A method in accordance with claim 1, wherein the front carriage and at least one rear carriage of the multi-part wheeled articulated vehicle are joined with each other by a vehicle joint.

9. A method in accordance with claim 8, wherein the vehicle joint is connected to the front and/or at least one rear rear carriage by metal rubber bearings, further comprising at least one sensor adapted to detect the forces and/or moments and the resulting displacements, torsions and/or tensions is disposed in the area of one of the metal rubber bearings.

10. A method in accordance with claim 8, wherein the vehicle joint includes two joint segments that are pivotably connected with each other and a measuring device for determining the angular position of the vehicle segments relative to each other.

11. A steering mechanism of a rear carriage of a multi-part wheeled land vehicle, in particular of an articulated bus, wherein the rear carriage is articulately joined with the front carriage, wherein the rear carriage comprises at least two axles, wherein at least the wheels of the front axle are designed to be steerable, wherein when the land vehicle drives around a bend, the forces and/or moments and resulting displacements and/or torsions and/or tensions acting on the front and/or rear carriages can be minimised by modifying the steering deflection angle of the wheels of the front axle of the rear carriage.

12. The steering mechanism according to claim 11, characterized in that when driving around a bend, the steering deflection angle of the wheels of the front axle of the rear carriage is provided to the steering mechanism of the front axle of the rear carriage as a value calculated based on the steering deflection angle of the wheels of at least one steerable axle of the front carriage, wherein in case of a deviation of the actual angular position of the wheels of the front axle of the rear carriage from the optimal value, the forces and/or moments and the resulting displacements, torsions and/or tensions acting on the front and/or rear carriage can be used by the steering mechanism for minimization through a modification of the angular position of the wheels of the front axle of the rear carriage.

13. The steering mechanism according to claim 11, characterized in that when driving around a bend, the steering deflection angle of the wheels of the front axle of the rear carriage is provided to the steering mechanism as a value calculated based on the angle between the longitudinal axis of the front carriage and that of the rear carriage, wherein, in case of a deviation of the actual angular position of the wheels of the front axle of the rear carriage from the optimal value, the forces and/or moments and the resulting displacements, torsions and/or tensions acting on the front and/or rear carriage can be used by the steering mechanism for minimization through a modification of the steering deflection angle of the front axle of the rear carriage.

14. The steering mechanism according to claim 11, characterized in that when driving around a bend, the steering deflection angle of the wheels of the front axle of the rear carriage is provided to the steering mechanism of the front axle of the rear carriage as a value calculated based on the steering deflection angle of the wheels of a rear axle of the rear carriage, wherein, in case of a deviation of the actual angular position of the wheels of the front axle of the rear carriage from the optimal value, the forces and/or moments and the resulting displacements, torsions and/or tensions acting on the front and/or rear carriage can be used by the steering mechanism for minimization through a modification of the steering deflection angle of the front axle of the rear carriage.

15. The steering mechanism according to claim 12, characterized in that the steering mechanism comprises a computer unit, in which the calculated values of the steering deflection angle of the wheels of at least one steerable axle of the front carriage, and/or of the angular positions of the front carriage and the rear carriage and/or of the steering deflection angle of the wheels of a rear axle of the rear carriage can be used for calculating a correction value, wherein the correction value is provided to the steering mechanism of the front axle of the rear carriage, wherein in case of a deviation of the angular position of the wheels of the front axle of the rear carriage, which has been set based on this correction value, from the technically optimal correction value, the forces and/or moments and resulting displacements, torsions and/or tensions acting on the front and/or rear carriages can be used by the steering mechanism for minimization by modifying the steering deflection angle of the front axle of the rear carriage.

16. The steering mechanism according to claim 11, characterized in that sensors are used for determining the forces and/or moments, displacements, torsions and/or tensions.

17. The steering mechanism according to claim 11, characterized in that the front and rear carriages of a multi-part wheeled articulated vehicle are joined with each other by a vehicle joint.

18. The steering mechanism according to claim 17, characterized in that the vehicle joint is connected to the front and/or rear carriage by metal rubber bearings, wherein at least one sensor for detecting the forces and/or moments and the resulting displacements, torsions and/or tensions is disposed in the area of the metal rubber bearing.

19. The steering mechanism according to claim 17, characterized in that the vehicle joint comprises two joint segments that are pivotably connected with each other, wherein the vehicle joint comprises a measuring device for determining the angular position of the vehicle segments relative to each other.

20. A multi-part wheeled land vehicle, comprising a control or regulation system for a steering mechanism according to claim 1.

21. A method for steering a rear carriage of a multi-part wheeled land vehicle, in particular of an articulated bus, wherein the rear carriage is joined with the front carriage, wherein the rear carriage comprises at least two axles, wherein the front carriage comprises at least one axle with steerable wheels, wherein at least the wheels of the front axle of the rear carriage are designed to be steerable, wherein the method comprises the following steps: calculating the steering deflection angle of the wheels of the front axle of the rear carriage based on the angle between the front and the rear carriage and/or on the angular position of the wheels of at least one steerable axle of the front carriage and/or on the angular position of the wheels of a rear axle of the rear carriage; adjusting the steering deflection angle of the wheels of the front axle of the rear carriage based on the calculated steering deflection angle; detecting the forces and/or moments and the resulting displacements and/or torsions and/or tensions acting on the front and/or rear carriage; and approximately minimizing the forces and/or moments and/or displacements and/or torsions and/or tensions by modifying the steering deflection angle of the wheels of the front axle of the rear vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 schematically shows an articulated vehicle;

[0028] FIG. 2 shows a vehicle joint with a front and rear carriage, which are merely hinted at; and

[0029] FIG. 3 shows a metal rubber bearing.

DETAILED DESCRIPTION OF THE INVENTION

[0030] According to FIG. 1, the articulated vehicle labelled 1 comprises the front carriage 3 and the rear carriage 5. The front and rear carriage 3, 5 are joined by the vehicle joint labelled 10. Both the front carriage 3 and the rear carriage 5 respectively comprise two axles 3a, 3b, respectively 5a, 5b. The wheels of the front axle 3a of the front carriage 3 are designed to be steerable, which also applies to the wheels of the front axle 5a of the rear carriage 5. The steering mechanism of the front axle 5a of the rear carriage 5 comprises an Ackermann-steering system and is labelled 6. The wheels of the rear axle of the rear carriage 5 can also be designed to be steerable.

[0031] FIG. 2 shows the embodiment of the vehicle joint 10. The vehicle joint 10 comprises two joint segments 11, 12, which are pivotably connected to each other by a pivot bearing 13. A so-called rotary encoder 14, by means of which the angular position of the two joint segments 11, 12 relative to each other and thus the position of the front carriage relative to the rear carriage can be determined, is disposed in the pivot bearing 13. In FIG. 2, the rotation angle is labelled α

[0032] The connection of the vehicle joint 10 to the front carriage 3 is carried out by way of two metal rubber bearings 20. The configuration of the two metal rubber bearings can be seen in FIG. 3. Such a metal rubber bearing comprises an axle journal 21, which is mounted under pre-tension on an elastomer pad 22 in a metal sleeve, which forms a housing 23. Such metal rubber bearings are sufficiently known from the prior art. The metal rubber bearing 20 with the housing 23 are received in a corresponding borehole in the joint segment 11. At its ends protruding from the housing 23, the axle journal 21 comprises respectively one borehole 24, which serves to receive respectively one screw for connecting it to a bearing block 4 disposed on the chassis of the front carriage 3. In the area of the metal rubber bearing, and here in particular in the metal rubber bearing itself, sensors (not shown) can be disposed, which serve to detect forces, moments, displacements, torsions and/or tensions. For example, theses sensors can be load cells, strain gauges or position or angle sensors.

LIST OF REFERENCE NUMBERS:

[0033] 1 Articulated vehicle [0034] 3 Front carriage [0035] 3a Front axle [0036] 3b Rear axle [0037] 4 Bearing block [0038] 5 Rear carriage [0039] 5a Front axle [0040] 5b Rear axle [0041] 6 Steering mechanism (Ackermann-steering mechanism) [0042] 10 Vehicle joint [0043] 11 Joint segment [0044] 12 Joint segment [0045] 13 Pivot bearing [0046] 14 Rotary encoder [0047] 20 Metal rubber bearing [0048] 21 Axle journal [0049] 22 Elastomer pad [0050] 23 Housing [0051] 24 Borehole