Patent ID: 7077235
Filing Date: 2006-07-18
Classification: B62D,F16C,F16H

Abstract:
1. An electric power steering apparatus comprising: a housing; a motor attached to said housing and transmitting an auxiliary steering force to a rotary shaft through a motor shaft; a bearing arrangement provided in said housing and rotatably supporting said rotary shaft by a shaft support hole; a worm rotating together with said rotary shaft and having a gear portion formed of a metal or a resin; an output shaft transmitting a steering force for steering an axle and rotatably supported in a predetermined position of said housing; a worm wheel rotating together with said output shaft in a way that meshes with said worm and having a gear portion formed of a resin; the auxiliary steering force of said motor being transmitted to said output shaft by cooperation of said worm and said worm wheel, wherein said motor is installed with respect to said output shaft in such a position that a length which is the sum of a working radius of said worm and a working radius of said worm wheel is set as an axis-to-axis distance between said output shaft and said motor shaft, and said bearing arrangement is installed with respect to said output shaft in such a position that an axis-to-axis distance between said shaft support hole and said output shaft is set slightly smaller than the axis-to-axis distance between said output shaft and said motor shaft.