Patent attributes
An automotive alternator includes a rotary shaft, a pulley, a stator, a rotor, and a magnetic fluctuation suppressor. The pulley is provided on the rotary shaft to transmit rotating power from an engine to the rotary shaft. The stator includes a stator winding. The rotor is mounted on the rotary shaft and configured to provide a first rotating magnetic field to the stator. The magnetic fluctuation suppressor includes a magnetic body and a magnetic source. The magnetic body is mounted on the rotary shaft such that the magnetic body is rotatable along with the rotary shaft at a rotational speed different from that of the rotary shaft. The magnetic source is fixed to the rotary shaft so as to create a second rotating magnetic field which induces a magnetic attraction between the magnetic body and the magnetic source, by which fluctuations in rotational movement of the rotary shaft are suppressed.
