Steering systems for vehicles

Patent metadata

Field	Value
Publication number	US-12291294-B2
Application number	US-202217696943-A
Country	US
Kind code	B2
Filing date	Mar 17, 2022
Priority date	Nov 3, 2020
Publication date	May 6, 2025
Grant date	May 6, 2025

Abstract

A steering system for a wheel of a vehicle comprises a pivot member having multiple pivot-node locations, and connectable at a first pivot-node location to a sub-frame of the wheel, a steering rod actuatable to rotate the wheel about a steering axis and mechanically coupled with the pivot member to be co-pivotable with the pivot member, and a suspension-connector rod having a first end that is connected to the pivot member at a second pivot-node location, and having at a second end that is connectable to a suspension arm linking the wheel of the vehicle to the sub-frame. When the steering system is installed in the vehicle, a lateral force acting upon the wheel is transmitted via the steering rod to the pivot member so as to rotate the pivot member, and the rotation is effective to transmit a substantially-vertical force vector to the sub-frame.

First claim

The invention claimed is:

1. A steering system for a wheel assembly of a vehicle, the steering system comprising:
a. a pivot member having multiple pivot-node locations, the pivot member connectable at a first pivot-node location to a sub-frame of the wheel assembly;
b. a steering assembly comprising a steering rod actuatable to rotate a wheel of the wheel assembly about a steering axis, a proximal portion of the steering rod being mechanically coupled with the pivot member to be co-pivotable therewith; and
c. a suspension-connector rod connected at a first end thereof to the pivot member at a second pivot-node location, the suspension-connector rod connectable at a second end thereof to a suspension arm linking the wheel of the wheel assembly to the sub-frame;

wherein the pivot member is disposed between the sub-frame and the steering axis.

2. The steering system of claim 1 , comprising an actuator connected to the steering rod and configured to cause the steering rod to move inwardly and outwardly, and an actuator-coupling connecting the actuator and the pivot member.

3. The steering system of claim 2 , wherein the actuator-coupling includes a bearing arrangement to allow the steering system to swivel relative to the pivot member such that a distal end of the steering rod can move to describe a generalized cone.

4. The steering system of claim 1 , wherein the wheel of the wheel assembly is one of two opposing, independently-suspended wheels.

5. The steering system of claim 1 , wherein when the vehicle is in motion and the wheel traverses a portion of a terrain characterized by a local change in terrain height, the pivot member is rotated by a force transmitted by the steering rod so as to reduce self-steering caused by the change in height.

6. The steering system of claim 5 , wherein self steering is reduced such that the steering motion of the suspended wheel is within ±1.2 degrees over the vertical motion of the suspended wheel.

7. A wheel assembly comprising:
a. a sub-frame configured to be mounted to a reference frame of a vehicle;
b. a wheel interface; and
c. a steering system according to claim 1 .

8. The wheel assembly of claim 7 , additionally comprising a drivetrain assembly comprising a rotatable drivetrain shaft connected to the wheel interface, the drivetrain shaft extending from a drivetrain motor towards the wheel interface.

9. The wheel assembly of claim 8 , additionally comprising the drivetrain motor.

10. A vehicle comprising: a pair of opposing wheel assemblies according to claim 7 , a corresponding pair of opposing wheels, and the reference frame.

11. The steering system of claim 1 , wherein a lateral force acting upon the wheel is transmitted via the steering rod to the pivot member so as to rotate the pivot member, the rotation being effective to transmit a substantially-vertical force vector to the sub-frame.

12. The steering system of claim 1 , wherein the steering rod is proximally actuatable to rotate the wheel about the steering axis.

13. The steering system of claim 1 , wherein a distal portion of the steering rod is, at least indirectly, mechanically coupled with the wheel.

14. The wheel assembly of claim 1 , wherein the steering assembly additionally comprises an actuator for causing the steering rod to move inwardly and outwardly, the actuator being mechanically coupled to the pivot member such that the steering assembly is co-pivotable with the pivot member about the first and second pivot-node locations.

15. The wheel assembly of claim 14 , wherein the mechanical coupling of the actuator includes a bearing arrangement to allow the steering assembly to swivel relative to the pivot member such that a distal end of the steering rod can move to describe a generalized cone.

16. A steering system of a wheel of a vehicle, the steering system comprising:
a. a pivot member having multiple pivot-node locations, and configured to be pivotably connected at a first pivot-node location to a reference frame of the vehicle;
b. a steering assembly comprising (i) a steering rod, actuatable to rotate the wheel about a steering axis, (ii) an actuator for causing the steering rod to move inwardly and outwardly, the actuator mechanically coupled to the pivot member such that the steering assembly is co-pivotable with the pivot member, and (iii) a powered steering motor for transmitting rotation energy to the actuator; and
c. a suspension-connector rod pivotably connected at a first end thereof to the pivot member at a second pivot-node location, and configured to be pivotably connected at a second end thereof to a suspension-arm linking the wheel of the vehicle to the reference frame,
wherein the mechanical coupling includes a bearing arrangement to allow the steering assembly to swivel relative to the pivot member such that a range of movement of a distal end of the steering rod describes a generalized cone.

17. The steering system of claim 16 , wherein when the steering system is installed in the vehicle, a lateral force acting upon the wheel is transmitted via the steering rod to the pivot member so as to rotate the pivot member, the rotation being effective to transmit an at-least-partly vertical force to the suspension-connector rod and a substantially-vertical force vector to the reference frame, the at least-partly-vertical force vector and the substantially-vertical force vector combining to mitigate body roll of the vehicle.

18. A method of mitigating body roll in a vehicle, the vehicle comprising two opposing axle-less, independently-suspended wheel assemblies, the method comprising:
providing, for each one of the two wheel assemblies, a steering system comprising (i) a pivot member having multiple pivot node locations and connected at a first pivot node location to a sub-frame of a respective wheel, (ii) a steering rod, actuatable to rotate the wheel about a steering axis, and mechanically coupled with the pivot member to be co-pivotable therewith, and (iii) a suspension-connector rod connected at a first end thereof to the pivot member at a second pivot-node location, and connected at a second end thereof to a suspension arm linking the wheel of the vehicle to the sub-frame; and
operating the vehicle, wherein during the operating a lateral force acting upon the wheel is transmitted via the steering rod to the pivot member so as to rotate the pivot member, the rotation transmitting a substantially-vertical force vector to the sub-frame.

Assignees

• Ree Automotive Ltd

Inventors

• Starik Eran
• Avigur Eylon

Classifications

• B60G3/26

  Means for maintaining substantially-constant wheel camber during suspension movement {; Means for controlling the variation of the wheel position during suspension movement (B60G3/202, B60G3/22, B60G7/003, B60G7/006 take precedence; means for adjusting camber, castor, or toe-in B62D17/00)} · CPC title

• B60G2200/182

  with one longitudinal arm or rod and lateral rods · CPC title

• B60G2204/15

  Mounting of subframes · CPC title

• B60G2204/148

  on the unsprung part of the vehicle, e.g. wheel knuckle or rigid axle · CPC title

• B60G2204/143

  on the vehicle body or chassis · CPC title