Patent ID: 7271518
Filing Date: 2007-09-18
Classification: H02K

Abstract:
1. A motor comprising: a fixed portion including a stator, the stator including at least one winding and a plurality of pole plates that extend to form a plurality of pole faces, with a gap being defined between a pair of the pole faces adjacent to each other, said at least one winding being energizable to make said pole faces create alternating magnetic fields; a rotor including a shaft and an annular magnet, the shaft rotatably extending in a longitudinal direction through the fixed portion, the annular magnet being mounted to an inner periphery of the rotor and facing said pole faces of the stator; and at least one magnetically conductive balancing plate mounted on the fixed portion, said at least one magnetically conductive balancing plate including at least two magnetically conductive faces that are respectively aligned with the pole faces of the stator, said at least two magnetically conductive faces being spaced from each other by a space that is aligned with an associated one of the gaps of the stator, said at least two magnetically conductive faces facing at least one face of the annular magnet and extending from an outer periphery of said balancing plate in the longitudinal direction; wherein when the rotor turns, the annular magnet of the rotor induces the alternating magnetic fields created by the stator and attracts said at least two magnetically conductive faces to thereby maintain rotational balance of the rotor.