IMPROVEMENTS RELATING TO ELECTRICAL POWER ASSISTED STEERING ASSEMBLIES

摘要

An electric power assisted steering system comprising an electric motor (4); a reduction gearbox (5) operatively connecting the motor to a portion of a steering shaft (1) such that upon rotation of the motor (4) through a complete electrical revolution the shaft moves through an angle dependent upon the reduction ratio of the gearbox (5); and a steering column torque sensor (6) which is adapted to produce an output signal which is indicative of the torque carried by the steering shaft (1) and which output signal also varies periodically throughout a rotation of the shaft, the period of the signal being equal to the said angle.