SINGLE-PHASE BRUSHLESS MOTOR

摘要

A single-phase brushless motor which can rotate smoothly by a uniform torque over an entire range of rotation with reduced torque ripples without generating a high cogging torque for allowing self-starting of the motor. The motor comprises a field magnet (2) as a rotor having 2P north and south magnetic poles, either the north or the south poles having a width equal to an electrical angle of about 120 degrees while the other poles have a width equal to an electrical of about 240 degrees. The field magnet (2) is mounted for rotation in an opposing relationship to a stator armature core (18) which has a plurality of radially extending stator poles (17-1 to 17-6) formed in a circumferentially equidistantly spaced relationship thereon. A plurality of stator coils (27-1 to 27-8) for two phases are wound selectively on the stator poles. An electric circuit detects the position of the field magnet to energize the armature coils (27-1 to 27-8) for the two phases alternately for an electric angle of about 180 degrees.