| 摘要 |
PROBLEM TO BE SOLVED: To provide a permanent magnet DC that lessens unbalance in counter EMF between the magnetic pole of a magnetic field and that of an induction field. SOLUTION: The electric motor has a housing, a rotor rotatably installed in the housing, and n permanent magnets of the same polarity fixed to an internal surface of the housing. The rotor is a wire-wound armature having a plurality of teeth extending in the radial direction. The housing includes n internal protrusions, the permanent magnets and internal protrusions are alternately disposed in the circumferential direction at a circumference of the rotor. The magnet generates 2n magnetic circuits through the housing and rotor, the n is an integer that is bigger than 1. At least the size of a part of a first air gap formed between the permanent magnet and rotor is bigger than at least that of a part of a second air gap formed between the internal protrusions and rotor. COPYRIGHT: (C)2010,JPO&INPIT |
