Patent ID: 7523805

Claim:
An electric power steering apparatus which transmits rotation of an output shaft of an electric motor in a housing to a steering shaft, thereby assisting steering operation, comprising: a pinion interlockedly connected to the output shaft; a first and a second bearing each supporting the pinion at a respective end of a pinion axis in the housing, each of the first and second bearing having an inner diameter and an outer diameter; and a gear wheel meshed with the pinion and concentrically fitted to the steering shaft, wherein the housing includes: a fitting bore in which the first bearing supporting one side of the pinion proximal to the electric motor is to be fitted; and a ring having an inner diameter larger than the outer diameter of the second bearing and provided at a position corresponding to the second bearing supporting another side of the pinion distal to the electric motor, and wherein the ring retains a coil spring such that a part of the coil spring is disposed on at least a part of an outer circumference of the second bearing, and a center of the coil spring is eccentrically oriented with respect to a central axis of the fitting bore toward a central axis of rotation of the gear wheel.