Patent ID: 7125169
Filing Date: 2006-10-24
Classification: F16C,H02K

Abstract:
1. A spindle motor comprising: a stator comprising a bracket, a sleeve affixed to said bracket, a core affixed to said bracket, and coils wound around said core; a rotor comprising a shaft, a rotating hub, and a rotor magnet; a pivot bearing comprising a pivot point at an end of said shaft rotating on said sleeve; a fluid dynamic journal bearing comprising said shaft, said sleeve, a fluid, and pressure generating grooves formed on a vertical surface of one of said shaft and said sleeve; a thrust-washer affixed to said shaft, said thrust washer containing a channel that provides for the circulation of said fluid; a counter-plate affixed to said sleeve and positioned partially over said thrust washer; and a fluid dynamic thrust bearing comprising said thrust-washer, said counter-plate, said fluid, and pressure generating grooves formed on a horizontal surface of one of said thrust-washer and said counter-plate; and where a gap exists between the bottom of said thrust-washer and said sleeve; a gap exists between the top of said thrust washer and said counter-plate; and the gap between the bottom of said thrust-washer and said sleeve is larger than the gap between the top of said thrust washer and said counter-plate.