TORQUE FEEDBACK SYSTEM FOR A STEER-BY-WIRE VEHICLE, VEHICLE HAVING STEERING COLUMN, AND METHOD OF PROVIDING FEEDBACK IN VEHICLE

• US 20170158222A1
• Filed: 07/27/2016
• Published: 06/08/2017
• Est. Priority Date: 12/03/2015
• Status: Active Grant

• Current Assignee: Steering Solutions IP Holding Corporation (Nexteer Automotive Group Ltd.)
• Original Assignee: Steering Solutions IP Holding Corporation (Nexteer Automotive Group Ltd.)
• Inventors: Bodtker, Joen C., Schulz, John F.
• Granted Patent: US 10,029,725 B2
• Time in Patent Office: Days
• CPC Class Codes: B62D 1/04 Hand wheels
• CPC Class Codes: B62D 1/20 Connecting steering column to steering gear
• CPC Class Codes: B62D 5/005 means for generating torque on steering wheel or input member, e.g. feedback
• CPC Class Codes: B62D 5/006 power actuated

Abstract

A torque feedback system for a vehicle includes a steering shaft having a longitudinal axis, a jacket surrounding the shaft, the shaft rotatable with respect to the jacket, and at least one mechanical energy storing element arranged to provide torque feedback when the steering shaft is rotated. The at least one mechanical energy storing element includes a first mechanical energy storing element having a first end engageable with the jacket and a second end engageable with the shaft, and a second mechanical energy storing element having a first end engageable with the jacket and a second end engageable with the shaft. The first mechanical energy storing element provides resistance to rotation of the shaft in a first rotational direction, and the second mechanical energy storing element provides resistance to rotation of the shaft in a second rotational direction.

Claims

1. A torque feedback system for a vehicle comprising:

a steering shaft having a longitudinal axis;

a jacket surrounding the shaft, the shaft rotatable with respect to the jacket; and

,

at least one mechanical energy storing element arranged to provide torque feedback when the steering shaft is rotated, the at least one mechanical energy storing element including a first mechanical energy storing element having a first end engageable with the jacket and a second end engageable with the shaft, and a second mechanical energy storing element having a first end engageable with the jacket and a second end engageable with the shaft, the first mechanical energy storing element provides resistance to rotation of the shaft in a first rotational direction, and the second mechanical energy storing element provides resistance to rotation of the shaft in a second rotational direction.

2. The torque feedback system of claim 1, wherein the first mechanical energy storing element is a first torsion spring, and the second mechanical energy storing element is a second torsion spring, wherein the second ends of the first and second torsion springs are connected to the shaft.

3. The torque feedback system of claim 2, wherein the first torsion spring is wound in a first direction around the shaft, and the second torsion spring is wound in a second direction around the shaft, the second direction opposite the first direction.

4. The torque feedback system of claim 2, wherein the jacket includes a contact portion, and the first end of the first torsion spring and the first end of the second torsion spring contact the contact portion in a non-rotated condition of the shaft.

5. The torque feedback system of claim 4, wherein rotation of the shaft in the first rotational direction increases a force of the first end of the first torsion spring on the contact portion and unloads the second torsion spring, and rotation of the shaft in the second rotational direction unloads the first torsion spring and increases a force of the first end of the second torsion spring on the contact portion.

6. The torque feedback system of claim 4, wherein rotation of the shaft in the first rotational direction maintains contact of the first end of the first torsion spring on the contact portion and separates the second end of the second torsion spring from the contact portion, and rotation of the shaft in the second rotational direction separates the first end of the first torsion spring from the contact portion and maintains contact of the first end of the second torsion spring on the contact portion.

7. The torque feedback system of claim 1, wherein the torque feedback system is disposed in an autonomous or semi-autonomous vehicle.

8. The torque feedback system of claim 1, wherein the mechanical energy storing element includes at least one spring having a first end engageable with a jacket surrounding the shaft a second end attached to the shaft, and further comprising a damper configured to damp oscillations of the at least one spring, the damper including one of a viscous damper and a friction damper.

9. The torque feedback system of claim 8, wherein the damper includes a damper housing surrounding at least a portion of the shaft, a movable member movable with the shaft and with respect to the housing, and fluid disposed within the damper housing.

10. The torque feedback system of claim 8, wherein the damper includes a piston linearly movable within a cylinder in response to rotational movement of the steering shaft.

11. The torque feedback system of claim 8, wherein the damper includes a fan blade.

12. The torque feedback system of claim 8, wherein the damper includes a rolling diaphragm containing a viscous fluid and movably supported between a fixed cylinder and a nut, the nut linearly translatable by rotation of the steering shaft.

13. The torque feedback system of claim 8, wherein the damper includes an eccentric cam surrounding the steering shaft, the eccentric cam engaging a spring biased towards the eccentric cam.

14. The torque feedback system of claim 8, wherein the damper includes at least one of a lip seal and a garter spring surrounding the steering shaft.

15. A vehicle comprising:

a steering wheel; and

,

a steering column including;

a steering shaft having a longitudinal axis, the steering shaft connected to the steering wheel for rotation of the steering shaft;

a jacket surrounding the shaft, the shaft rotatable with respect to the jacket; and

,

at least one first spring having a first end engageable with the jacket and a second end connected to the shaft, the at least one first spring wound in a first direction around the shaft.

16. The vehicle of claim 15, further comprising at least one second spring having a first end engageable with the jacket and a second end connected to the shaft, the at least one second spring wound in a second direction around the shaft, the second direction opposite the first direction.

17. The vehicle of claim 15, wherein the vehicle is an autonomous or semi-autonomous vehicle having a steer-by-wire system, and further comprises an actuator operatively connected to road wheels of the vehicle, the actuator electrically connected to the steering column in a driver-operated mode of the vehicle and electrically disconnected from the steering shaft in an activated autonomous mode.

18. The vehicle of claim 15, wherein the steering column further includes a damper configured to damp oscillations of the at least one first spring.

19. A method of providing torque feedback to a driver of a vehicle, the method comprising:

providing a steering shaft in a non-rotated condition, a first end of a first torsion spring engaged with a contact portion of a steering column jacket, a second end of the first torsion spring attached to the steering shaft, a first end of a second torsion spring engaged with the contact portion of the steering column jacket, a second end of the second torsion spring attached to the steering shaft;

rotating the steering shaft in a first direction;

increasing a force applied by the first end of the first torsion spring on the contact portion while rotating the steering shaft in the first direction;

rotating the steering shaft in a second direction opposite the first direction; and

,

increasing a force applied by the first end of the second torsion spring on the contact portion while rotating the steering shaft in the second direction.

20. The method of claim 19, further comprising damping oscillations of the first and second torsion springs using a damper at least partially surrounding the steering shaft.