ELECTRIC POWER STEERING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an electric power steering device which can improve vehicle mounting performance by integrating an electric motor and a speed reducer to be disposed on an assist pinion.SOLUTION: When a pinion shaft 12 is in CW rotation, phase of an internal tooth 23 coincides with phase of an external tooth 24 at a SET3, electric current flowing through a coil 17 returns to zero from an electric current value in a suction state, the internal tooth 23 is pressed by an elastomer 25 for return, is separated from the adhesion state with the external tooth 24 and is released. At a subsequent SET2, the phase of the internal tooth 23 is shifted clockwise by a phase differenceθwith respect to the phase of the external tooth 24, the electric current flowing through the coil 17 gets to the maximum electric current value in the suction state, a contacting reaction force is operated clockwise onto the external tooth 24 by the contacting of a tooth surface, the contacting reaction force gets larger than the suction force and the an assist torque is generated. At remaining respective SETs, a small electric current which generates a repulsive force flows through a coil 17 and returns the internal tooth 23 to an outer side in the radial direction and the interference with the external tooth 24 is prevented.