Patent attributes
There is provided a bearingless step motor in which a rotating shaft can rotate while rising from a main body by a magnetic force without using a mechanical bearing. The bearingless step motor comprises a stator including stator cores having winding portions and a rotor including a rotating shaft and rotor cores. The rotor rotates by a magnetic interaction between the rotor cores and the stator cores. A first permanent magnet is mounted to the rotor and a second permanent magnet is mounted to the stator. The first permanent magnet and the second permanent magnet are arranged so that a repulsive force is generated between magnetic poles. There is little power consumption for raising the rotating shaft and a complicated system for controlling the rise of the rotating shaft is unnecessary. Thus, the motor can be manufactured with a light and compact structure.