METHOD AND APPARATUS FOR DETECTING VACUUM POSITION IN VACUUM MOTOR

摘要

A vacuum position detecting method in vacuum motor in which the degree of freedom can be increased in the design of motor without sacrifice in reliability, and a thin lightweight vacuum position detector which can detect the absolute angle. In a method for detecting a position by providing a rotor (3) rotatable through a bearing (6) in a motor case having a stator (1) with a detector rotor disposed on the vacuum side, the detector rotor comprises a planar slit disc (5) made by making a plurality of slits in the plane of a magnetic steel plate and a slit disc base for securing it, a magnetic sensor head (2) comprising an MR magnet and a permanent magnet resin sealed in a sensor case is disposed on the stator (1) side oppositely to the slit disc (5), and the magnetic sensor head (2) detects presence of the slit made in the surface of the slit disc (5).