POWER-STEERING DEVICE

摘要

This power-steering device is provided with a main unit (DB) and a hollow motor (30). The main unit (DB) has a steering mechanism in which steering (rotational) torque transmitted from an input shaft (11) to an output shaft (12) is converted into rotation of a sector shaft (17) via axial movement of a piston (16), thereby changing a steering angle. Said piston (16) is disposed so as to encircle the output shaft (12) with a ball-screw mechanism (20) interposed therebetween. The hollow motor (30) encircles the input shaft (11) and is coupled thereto, and the flow of current to the hollow motor (30) is controlled on the basis of driving-assistance information from a vehicle-mounted camera or the like. The hollow motor (30) is coupled to the input shaft (11) via a key linkage comprising a key (25) protruding from the outer surface of the input shaft (11) and a key groove (39e) cut into the inner surface of a rotor (31) that is part of the hollow motor (30).