Electric power steering system

摘要

An electric power steering system for an automotive vehicle, includes a torque sensor disposed to a steering shaft to detect a steering torque. A first pinion is disposed to the steering shaft. A rack shaft is in mesh with the first pinion and connected with the steering shaft to change a rotational motion of the steering shaft to an axial motion of the rack shaft and provided to be operated in relation to the steering shaft. A first motor is connected with the first pinion to generate a steering assist torque in accordance with the steering torque detected by the torque sensor. A second pinion is disposed to be separate from the first pinion and in mesh with the rack shaft. A second motor is connected with the second pinion to generate a steering assist torque in accordance with the steering torque.