SUPERSONIC MOTOR WITH MAGNETIC ENCODER

摘要

A supersonic motor provided at the outer periphery or the upper surface or the lower surface of the outer peripheral portion of a rotary member (1) with a first track (13b) on which magnetic poles are continuously alternately magnetized and a second track (13c) on which at least one magnetic pole is magnetized at one place, the first and second tracks being disposed through a not-magnetized member (13a); and with a magnetic encoder opposite to the first and second tracks (13b and 13c) for detecting a rotational position and the speed of a rotor (13); so that the magnetic sensitive element (14) detects variation in the magnetic flux of the first track (13b) and second track (13c) caused by rotation of the rotor (13) and sends a signal to a position control circuit (16) and a speed control circuit, resulting in that a command signal generated from the respective control circuits (16 and 17) can improve accuracy for the position and speed control of the supersonic motor (19). Also, the above construction makes the supersonic motor (19) compact, lightweight and smaller in thickness.