PURPOSE: To simplify the structure and to achieve the reduction of size by sequentially exciting plural coils to generate rotating magnetic field with such number of poles as the number of poles of a rotor ±2 along the inner peripheral surface of a stator.

CONSTITUTION: When coils 6, 6... of a stator 5 are sequentially excited to generate rotating magnetic field with such number of poles as the number of poles of a rotor 8±2, that is, six poles or two poles, it is possible to apply the continuous displacing force in the fixed direction to the rotor 8, so that the continuous floating force can be obtained by setting the displacing force applied to the rotor 8 always upward. In this case, as the device has the same structure as a servo motor and a synchronous motor, it is possible that the device is formed on the ends of both shafts of the above motors, or coils functioning as a magnetic bearing are added to coils functioning as a servo motor to be integral with the motor. Thus, the structure can be simplified and the whole device can be reduced in size as compared with the conventional magnetic bearing where plural electromagnets have to be firmly fixed.