Patent ID: 6036369
Filing Date: 2000-03-14
Classification: F16C,G11B

Abstract:
A fluid dynamic pressure bearing comprising:a shaft member having an outer bearing surface;a sleeve member having an inner bearing surface and rotatable relatively to said shaft member, said shaft member being surrounded by the sleeve member with the outer bearing surface of the shaft member confronting the inner bearing surface of the sleeve member with a gap therebetween; andlubricating fluid filled in the gap, at least one of the inner and outer bearing surfaces being formed with a bearing groove for generating a dynamic pressure in said lubricating fluid during the relative rotation of the shaft member and the sleeve member, said outer surface of the shaft member being inclined to form a tapered seal at one end portion of the gap where the gap communicates with outside atmosphere, and the portion of the inner surface of the sleeve member opposing the inclined surface being formed with an annular stepped portion for trapping fluid migration over the opposing surface.