Patent ID: 7002274

Claim:
A rotary electric machine comprising: a stator provided with windings; a rotor including axially arranged first and second rotor bodies each provided with field magnets of different polarities alternately arranged in a rotating direction; and an axial position changing mechanism for changing the axial position of the second rotor body relative to the first rotor body according to balance of magnetic force acting between the field magnets of the first rotor body and those of the second rotor body, and the direction of torque of the rotor; wherein, in changing the axial position of the second rotor body relative to the first rotor body to a predetermined position such that the intensity of a combined magnetic field created by the field magnets is reduced, the second rotor body is moved axially to the predetermined position after axially moving the second rotor body relative to the first rotor body to a position that makes the intensity of a combined magnetic field lower than that of a combined magnetic field that is created when the second rotor body is moved to the predetermined position.