Patent ID: 7021829
Filing Date: 2006-04-04
Classification: F16C,G11B,H02K,Y10T

Abstract:
1. A fluid-dynamic-pressure bearing comprising: a shaft; a top plate fixed to an upper portion of the shaft; a thrust plate fixed to a bottom portion of the shaft; a circular cylindrical sleeve, either said sleeve or said shaft being rotatable relative to the other, said sleeve with respect to said shaft and with respect to said top plate defining a continuous micro-gap; a roughly cuplike bearing housing inner-circumferentially retaining the sleeve and whose lower end is closed; lubricating fluid filling the micro-gap; a radial bearing component formed in between respective surfaces of said shaft outer-circumferentially and said sleeve inner-circumferentially, said radial bearing component being provided with radial dynamic-pressure-generating grooves for inducing dynamic pressure in said lubricating fluid when either said shaft or said sleeve spins; an upper thrust bearing section formed in between respective surfaces of said top plate bottom-wise and said bearing housing rim-wise, said upper thrust bearing section being provided with upper thrust dynamic-pressure-generating grooves for inducing dynamic pressure in said lubricating fluid when either said shaft or said sleeve spins; and a lower thrust bearing section formed in between respective surfaces of said sleeve bottom-marginally and said thrust plate top-marginally, said lower thrust bearing section being provided with lower thrust dynamic-pressure-generating grooves for inducing dynamic pressure in said lubricating fluid when either said shaft or said sleeve spins.