Patent ID: 6104113
Filing Date: 2000-08-15
Classification: H02K,H02P,Y10S

Abstract:
A motor comprising:a rotor having a generally cylindrical rotor core and a plurality of permanent magnet elements generating a magnetic field, said permanent magnet elements being situated radially on an outer surface of the rotor core so that each permanent magnet element has an axially facing end portion which extends past one end of the rotor core;a stator having a main winding which is in magnetic coupling relationship with the rotor, said stator and said rotor being positioned radially with respect to each other and defining an air gap therebetween, said end portion of each permanent magnet element also extending past one end of the stator;a coil assembly generating an output signal representative of rotor angular position relative to the stator when the rotor is rotating, said coil assembly being positioned axially adjacent the one end of the rotor core in magnetic coupling relationship with the rotating magnetic field of the permanent magnet elements of the rotor and substantially independent of the magnetic coupling relationship between the main winding of the stator and the rotor, said coil assembly comprising a coil of wire generating the output signal and a coil fixture for holding the coil of wire axially adjacent the one end of the rotor core; anda control circuit receiving and responsive to the output signal for commutating the main winding as a function of the rotor angular position.