Patent ID: 6712514
Filing Date: 2004-03-30
Classification: F16C

Abstract:
A hydrodynamic bearing unit comprising:a housing with a bottom portion; a bearing member fixed to the inner circumference of the housing; a shaft member having a shaft portion inserted into the inner circumference of the bearing member, and a flange portion; a radial bearing portion provided between the inner circumference of the bearing member and the outer circumference of the shaft portion of the shaft member for supporting the shaft member in a radial direction in non-contact state with a dynamic pressure generated in a radial bearing clearance; and a thrust bearing portion respectively provided between each end surface of the flange portion of the shaft member and an end surface of the bearing member or an inner surface of the bottom portion of the housing for supporting the shaft member in a thrust direction in non-contact state with a dynamic pressure generated in thrust bearing clearances; wherein the parallelism between the inner surface and the outer surface of the housing is 0.005 mm or less.