Patent ID: 6702466
Filing Date: 2004-03-09
Classification: F16C,H02K

Abstract:
A ceramic dynamic-pressure bearing comprising a dynamic-pressure gap formed between a first member and a second member, which undergo relative rotation about a predetermined axis of rotation, and the relative rotation of the first member and the second member generates fluid dynamic-pressure in the dynamic-pressure gap,wherein at least a portion of at least either the first member or the second member which includes a dynamic-pressure gap definition surface facing the dynamic-pressure gap is formed of electrically conductive ceramic, and dynamic-pressure grooves are formed on the ceramic dynamic-pressure gap definition surface such that, on a cross section of a dynamic-pressure groove taken perpendicular to a longitudinal direction of the groove, a curvature portion having a radius of 3-7 &mgr;m is formed at a position where a groove sidewall surface and a groove bottom surface meet.