DEVICE FOR DETECTING MOTOR ROTARY POSITION

摘要

PROBLEM TO BE SOLVED: To easily and highly precisely detect a rotary reference position while promoting the miniaturization of a motor. SOLUTION: A sensor for detecting the approach of a permanent magnet 2 provided at the prescribed position of a rotor and a permanent magnet 3 arranged at a coil 9 side, and detecting a prescribed rotational position, is constituted of a hole element 7 in a uni-directional magnetic field. A polarizing part 3a of the permanent magnet 3 projected to an axial direction is constituted of an S pole, and the hole element 7 in the uni-directional magnetic field is fixed to a position which can be faced to the polarizing part 3a of the permanent magnet 3.