Patent ID: 6951261

Claim:
A power steering system for a vehicle, the power steering system comprising: a steering shaft; an elastic member, which is connected to the steering shaft and is twistable around an axis of the elastic member by a steering torque applied to the steering shaft; a torque sensor, which includes: a galvanomagnetic element, which outputs an analogue electrical signal corresponding to an amount of torsional twist of the elastic member, which is twisted by the steering torque; an AD converter circuit, which converts the analogue electrical signal to a digital signal; and a communication means for performing digital communications; an electric motor, which applies a steering assisting force to the steering shaft or a steering rack connected to the steering shaft; a drive circuit, which drives the electric motor; and a motor control means for controlling the electric motor through the drive circuit, wherein: the motor control means obtains a value of the steering torque based on the digital signal transmitted from the communication means and outputs a drive signal to the drive circuit in such a manner that electric current corresponding to the steering torque is supplied to the electric motor; and the motor control means includes an electric power steering ECU, which includes a digital communication means for communicating with the communication means of the torque sensor and at least one other controller of the vehicle, wherein the electric power steering ECU processes communications with the communication means of the torque sensor and communications with the at least one other controller of the vehicle in such a manner that the communications between the communication means of the torque sensor and the digital communication means of the electric power steering ECU has priority over communications between the at least one other controller of the vehicle and the digital communication means of the electric power steering ECU.