Hand wheel actuator with steering-feel enhancement
First Claim
1. A hand wheel actuator for a steer-by-wire steering system comprising:
- a first housing having an aperture;
a steering shaft extending through said first housing, said steering shaft having an upper end adapted for attaching a hand wheel, and a lower end opposite said upper end, said steering shaft being rotatably supported by said first housing;
a position sensor and a non-compliant torque sensor, each positioned within said first housing and configured to detect the angular displacement of the steering shaft and torque applied against the steering shaft respectively;
a mechanical steering feel enhancement device attached to said first housing, said mechanical steering feel enhancement device providing at least one of a positive stop function, a return-to-center function, or a friction/weight function by mechanical means, said mechanical steering feel enhancement device being in mechanical communication with said steering shaft, and said mechanical steering feel enhancement device being disposed in a second housing and existing as a separate unitary subassembly prior to being installed on said first housing; and
an electric motor mounted to one of said first housing and second housing, said electric motor having an output shaft in mechanical communication with said steering shaft for imparting a torque to said steering shaft;
wherein said torque sensor is positioned between the upper end of the steering shaft and a location at which the motor applies torque to the steering shaft and wherein said first housing separates and shields said non-compliant torque sensor from magnetic fields generated by said electric motor.
11 Assignments
0 Petitions
Accused Products
Abstract
A hand wheel actuator for a steer-by-wire steering system having a steering feel that meets drivers'"'"' expectations is provided with a housing having an aperture, a steering shaft extending through the aperture and rotatably supported by the housing, an electric motor, a position sensor and torque sensor, and a mechanical steering feel enhancement device. The mechanical steering feel enhancement device is attached to the housing and provides a positive stop function, a return-to-center function, and/or a friction/weight function. The mechanical steering feel enhancement device is in mechanical communication with the steering shaft and may exist as a separate unitary subassembly prior to being installed on the housing. The electric motor has an output shaft that is in mechanical communication with the steering shaft for imparting a torque to the steering shaft.
55 Citations
16 Claims
-
1. A hand wheel actuator for a steer-by-wire steering system comprising:
-
a first housing having an aperture;
a steering shaft extending through said first housing, said steering shaft having an upper end adapted for attaching a hand wheel, and a lower end opposite said upper end, said steering shaft being rotatably supported by said first housing;
a position sensor and a non-compliant torque sensor, each positioned within said first housing and configured to detect the angular displacement of the steering shaft and torque applied against the steering shaft respectively;
a mechanical steering feel enhancement device attached to said first housing, said mechanical steering feel enhancement device providing at least one of a positive stop function, a return-to-center function, or a friction/weight function by mechanical means, said mechanical steering feel enhancement device being in mechanical communication with said steering shaft, and said mechanical steering feel enhancement device being disposed in a second housing and existing as a separate unitary subassembly prior to being installed on said first housing; and
an electric motor mounted to one of said first housing and second housing, said electric motor having an output shaft in mechanical communication with said steering shaft for imparting a torque to said steering shaft;
wherein said torque sensor is positioned between the upper end of the steering shaft and a location at which the motor applies torque to the steering shaft and wherein said first housing separates and shields said non-compliant torque sensor from magnetic fields generated by said electric motor. - View Dependent Claims (2, 3, 4)
a first spool on said auxiliary shaft;
a second spool on said steering shaft, said constant force spring having a first end fixed to said first spool and a second end fixed to said second spool, said constant force spring extending between said first spool and said second spool.
-
-
5. A hand wheel actuator for a steer-by-wire steering system comprising:
-
a steering shaft, said steering shaft having an upper end adapted for attaching a hand wheel, and a lower end opposite the upper end;
a steering shaft housing, said steering shaft extending through said steering shaft housing and rotatably supported by said steering shaft housing, said steering shaft housing containing a mechanical steering feel enhancement device in mechanical communication with said steering shaft;
a driver interface electronics module attached to an upper end of said steering shaft housing, said driver interface electronics module comprising a control unit, and driver interface controls including a stalk-mounted switches;
said driver interface electronics module existing as a subassembly prior to being mounted on said steering shaft housing;
a position sensor and a non-compliant torque sensor, each positioned within the handwheel actuator and configured to detect the angular displacement of the steering shaft and torque applied against the steering shaft respectively;
an electric motor and a transmission placing said electric motor and said steering shaft in mechanical communication, said electric motor being attached to a lower portion of said steering shaft housing opposite said driver interface electronics module;
wherein said torque sensor is positioned between the upper end of the steering shaft and a location at which the motor applies torque to the steering shaft and wherein the housing separates and shields the torque sensor from magnetic fields generated by said electric motor. - View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
a first spool on said auxiliary shaft;
a second spool on said steering shaft, said constant force spring having a first end fixed to said first spool and a second end fixed to said second spool, said constant force spring extending between said first spool and said second spool.
-
-
15. The hand wheel actuator of claim 14 further comprising a first pulley on said steering shaft, a second pulley on said auxiliary shaft, and a belt extending from said first pulley to said second pulley thereby placing said auxiliary shaft in mechanical communication with said steering shaft.
-
16. The hand wheel actuator of claim 15 wherein said belt is a timing belt and has teeth engaging mating structures on each of said first pulley and said second pulley, thereby maintaining a constant turn ratio between said first pulley and said second pulley.
Specification