Patent ID: 8240422

Claim:
A steer-by-wire steering system comprising a steering wheel mechanically isolated from a steering axle, a steering angle sensor for detecting a steering angle of the steering wheel, a steering motor, a steering power transmitting mechanism for transmitting a rotation of the steering motor to the steering axle, a toe angle adjusting motor, a toe angle adjusting power transmitting mechanism for adjusting a toe angle by means of a rotation of the toe angle adjusting motor, and a steering control section for generating a command signal of a wheel-turning angle and a command signal of the toe angle on the basis of the steering angle detected by the steering angle sensor and applying those command signals to the steering motor and the toe angle adjusting motor; in which there is provided a switching mechanism operable in the event of failure of the steering motor to disconnect the steering motor from the steering power transmitting mechanism and to transmit the rotation of the toe angle adjusting motor in place of the steering motor to the steering power transmitting mechanism, while restraining the toe angle from changing, to enable a vehicle wheel to turn and, also, operable in the event of failure of the toe angle adjusting motor to disable the toe angle adjusting power transmitting mechanism from transmitting a motion and to enable only a vehicle wheel turning by the steering motor; and in which one or both of the steering motor and the toe angle adjusting motor is or are employed in the form of a hollow motor.