Patent ID: 6140728
Filing Date: 2000-10-31
Classification: B62D,H02K

Abstract:
An electric motor comprising:a stator, the stator having a plurality of tooth parts, each tooth part having a radially inner side end and a radially outer side end, the radially inner side end of each tooth part having a magnetic pole portion extending in a circumferential direction and a protruded portion protruding in the circumferential direction from the radially outer side end, the magnetic pole portion and protruded portion defining a coil mounting portion wrapped by an insulating sheet;a coil provided around each tooth part;a yoke having a plurality of dovetail grooves extending along a radially inner peripheral surface of the yoke, the yoke containing the tooth parts and coil, the tooth parts, coil and yoke being integrated by molding using a resin having at least one of adhesion and electric insulation characteristics;a rotor that rotates within the stator, the rotor having an outer peripheral surface; anda plurality of permanent magnets disposed on the outer peripheral surface of the rotor, each magnet having a radially inner side surface, a radially outer side surface and a pair of opposite ends, the radially inner side surface of each magnet being curved to generally be convex in a radially inward direction and the outer peripheral surface of the rotor having a plurality of curved recess surfaces, each of the curved recess surfaces contacting the radially inner side curved surface of a corresponding magnet.