Redundant gear assembly for vehicle steering column and method
A redundant gear assembly for a vehicle steering column includes a gear operatively coupled to a steering column component. Also included is a first and second set of gear teeth on the gear. Yet further included is a first motor driving a first gear input component, the first gear input component in meshed engagement with the first set of gear teeth to provide a first steering assist torque that is representative of a desired steering assist torque in a primary operating mode of the redundant gear assembly. Also included is a second motor driving a second gear input component, the second gear input component in meshed engagement with the second set of gear teeth to provide a second steering assist torque in a redundant operating mode of the redundant gear assembly, the second motor not driving the second gear input component in the primary operating mode.
1. A redundant gear assembly for a steering column comprising:
a gear operatively coupled to a steering column component;
a first set of gear teeth on the gear;
a second set of gear teeth on the gear;
a first motor driving a first gear input component, the first gear input component in meshed engagement with the first set of gear teeth to provide a first steering assist torque that is representative of a desired steering assist torque in a primary operating mode of the redundant gear assembly; and
a second motor driving a second gear input component, the second gear input component in meshed engagement with the second set of gear teeth to provide a second steering assist torque in a redundant operating mode of the redundant gear assembly, the second motor not driving the second gear input component in the primary operating mode.
2. The redundant gear assembly of claim 1 , wherein the second motor provides less than the desired steering assist torque in the redundant operating mode.
3. The redundant gear assembly of claim 1 , wherein the second motor provides a torque representative of the desired steering assist torque in the redundant operating mode.
4. The redundant gear assembly of claim 1 , wherein the first gear input component is a first worm forming a first worm gear arrangement with the gear and the second gear input component is a second worm forming a second worm gear arrangement with the gear, the first set of gear teeth disposed on an outer circumferential surface of the gear and adjacent to a first face of the gear, the second set of gear teeth disposed on the outer circumferential surface and adjacent to a second face of gear.
5. The redundant gear assembly of claim 4 , wherein the first set of gear teeth and the second set of gear teeth overlap in an axial direction of the gear.
6. The redundant gear assembly of claim 1 , wherein the first gear input component and the gear form one of a worm gear arrangement, a face gear arrangement, a spur gear arrangement, a helical gear arrangement, and a spiroid gear arrangement, the second gear input component and the gear forming one of a worm gear arrangement, a face gear arrangement, a spur gear arrangement, a helical gear arrangement, and a spiroid gear arrangement.
7. The redundant gear assembly of claim 1 , wherein the vehicle steering column is a steer by wire system.
8. The redundant gear assembly of claim 1 , wherein the vehicle steering column is disposed in an autonomous or semi-autonomous vehicle.
9. The redundant gear assembly of claim 8 , wherein the first gear input component and the gear form one of a worm gear arrangement, a face gear arrangement, a spur gear arrangement, a helical gear arrangement, and a spiroid gear arrangement, the second gear input component and the gear forming one of a worm gear arrangement, a face gear arrangement, a spur gear arrangement, a helical gear arrangement, and a spiroid gear arrangement.
10. The redundant gear assembly of claim 8 , wherein the vehicle steering column is a steer by wire system.
11. The redundant gear assembly of claim 8 , wherein the vehicle steering column is disposed in an autonomous or semi-autonomous vehicle.
12. A redundant gear assembly for a steering column comprising:
a gear operatively coupled to a steering column component;
a first set of gear teeth on the gear;
a second set of gear teeth on the gear;
a first motor driving a first gear input component, the first gear input component in meshed engagement with the first set of gear teeth to provide a first steering assist torque in a primary operating mode of the redundant gear assembly; and
a second motor driving a second gear input component, the second gear input component in meshed engagement with the second set of gear teeth to provide a second steering assist torque in the primary operating mode.
13. The redundant gear assembly of claim 12 , wherein the first steering assist torque and the second steering assist torque provide a combined steering assist torque that is representative of a desired steering assist torque.
14. The redundant gear assembly of claim 13 , wherein the first steering assist torque is 50% of the desired steering assist torque and the second steering assist torque is 50% of the desired steering assist torque.
15. The redundant gear assembly of claim 12 , wherein the first motor and the second motor are each operable to provide a torque representative of a desired steering assist torque.
16. The redundant gear assembly of claim 12 , wherein the first gear input component is a first worm forming a first worm gear arrangement with the gear and the second gear input component is a second worm forming a second worm gear arrangement with the gear, the first set of gear teeth disposed on an outer circumferential surface of the gear and adjacent to a first face of the gear, the second set of gear teeth disposed on the outer circumferential surface and adjacent to a second face of gear.