PURPOSE: To reduce the weight and the moment of intertia of a motor, by arranging superconductive bodies on the surface of a rotor.

CONSTITUTION: A plurality of superconductive bodies 8a∼8h are arranged on the cylindrical surface of a rotor 7 for a brushless motor by means of spattering or the like with an interval provided as equal as possible. The prosalient poles 9A∼9C of a stator 11 are provided with coils 10A∼10C respectively while a phase detector 12 is connected mechanically to the rotor 7. A drive circuit 13 commutates currents conducted through the coils 10A∼10C based on the signal 125 of the phase detector 12 to generate a rotating magnetic field in the stator 11. According to this method, the superconductors 8a∼8h are opposed to N-poles or S-poles, generated in the salient poles 9A∼9C of the stator 11 whereby a magnetic repulsive force is generated by diamagnetic effect. As a result, the rotor 7 may be rotated into a desired direction.