Patent ID: 7584819

Claim:
A vehicle steering system for steering vehicle wheels, said system comprising: a steering wheel; a steering power assisting unit for providing assisting power when said steering wheel is steered; a transfer ratio control mechanism, including a transfer ratio changing mechanism and a driving motor for driving said transfer ratio changing mechanism, for controlling a ratio of a steering angle of said steering wheel to a steered angle of said vehicle wheels; a steering torque sensor that detects steering torque applied to said steering wheel; and a motor control circuit for driving said driving motor based on at least the detected steering torque to achieve a suitable ratio of a steering angle of said steering wheel to a steered angle of said vehicle wheels, wherein said motor control circuit comprises means for controlling said driving motor to generate a torque so as to cancel the steering torque applied to said steering wheel when said steering torque sensor detects steering torque applied to said steering wheel before said driving motor is driven by said motor control circuit.