PURPOSE: To efficiently save power consumption by turning ON, OFF an input power source by utilizing the inertial moment of a flywheel.

CONSTITUTION: A coil movable type 5 is formed of a ringshaped magnet 4, and a generator is rotated by the torque of the centeral shaft 7 of its supporting rod 6. When part of a cylindrical magnet 8 is cut out, a coil 9 is supported by a supporting rod 10 near a uniform magnetic field type, and the central shaft 11 of the rod 10 is closely contacted with the generator, the efficiency is further increased. Moreover, a flywheel 13 is separately provided at the shaft 7, an input power source is turned ON, OFF by the inertial moment to efficiency save the power consumption.