Patent ID: 6340854
Filing Date: 2002-01-22
Classification: F16C,H02K

Abstract:
A scanner motor comprising:a circuit board; a cylindrical sleeve coupled to the circuit board at a lower end thereof, the cylindrical sleeve being attached, at the lower end thereof, with a cap adapted to cover the lower end thereof; a stator assembly fitted around the sleeve in a vertical direction, the stator assembly including a core wound with coils; a sintered bearing tightly fitted in the sleeve in a vertical direction, the sintered bearing having upper and lower dynamic pressure generating grooves formed at upper and lower portions of an inner peripheral surface thereof, respectively; an annular fixed magnet fitted in an upper end of the sleeve, the fixed magnet having opposite poles vertically arranged; a shaft vertically inserted in the sintered bearing, the shaft being spaced, at a lower end thereof, apart from the cap by a desired height; an annular rotating magnet fitted around the shaft while having opposite poles vertically arranged, the rotating magnet facing the fixed magnet in a horizontal direction in such a fashion that the horizontally facing poles thereof have opposite polarities attracting each other, respectively; and a rotor case coupled at an upper end thereof to an upper end of the shaft above the rotating magnet, the rotor case having a cylindrical skirt extending downwardly from the upper end thereof, the rotor case being attached with a polygon mirror at a top surface thereof and with an annular driving magnet at an inner peripheral surface of the skirt in such a fashion that a yoke is interposed between the driving magnet and the skirt.