To enhance the efficiency of rotational energy to input energy by making the reaction and attraction that a permanent magnet potentially acts upon a magnetic rotator at the same time and utilizing it effectively.

For permanent magnets 2 provided by an arbitrary number of sets around a rotatable rotor 1, plural pieces of permanent magnets 21 are arranged at roughly equal intervals in the circumferential direction, with each one magnetic pole corresponding to each other, directed in the rotation direction and the other magnetic poles directed in the direction of reverse rotation. An arbitrary number of sets of electromagnet means 3 provided opposite to this magnet device 2 have two different magnetic poles N and S, acting as rotational energy in one direction at the same time, and both magnetic poles N and S generate controlled magnetic fields intermittently.