PURPOSE: To generate a turning force efficiently by constituting rotors each composed of three permanent magnets or more so that said rotors have two pairs or more of proximity points to be rotated and driven in parallel, and by rotating each pair of rotors at said proximity points through the repulsive force of said permanent magnets.

CONSTITUTION: An apparatus is provided with units each composed of a driving rotor 4a and a driven rotor 4b turning around parallel shafts 2. The outer periphery of said rotors 4a and 4b is provided with a plurality of permanent magnets 8a and 8b at equal spaces. The direction of the magnetic axis of each permanent magnet 8a, 8b is inclined at an appropriate angle to the radial direction of rotor for each of the driving and driven rotors 4a and 4b. When respective rotors 4a, 4b are linked together for rotation, like poles periodically approach and face each other and poles 8a of the driving rotor 4a are caused to precede poles 8b of the driven rotor 4b only a little. When output is made larger, the number of units is increased. Thus, the efficiency in use of a magnet is improved and a turning force is generated efficiently.