Patent ID: 7011450
Filing Date: 2006-03-14
Classification: F16C,G11B

Abstract:
1. A fluid dynamic bearing device comprising: a sleeve having a bearing hole; a shaft relatively rotatably inserted into the bearing hole; and a thrust bearing member fixed to an end face of the sleeve and making contact with one end face of the shaft, wherein a thrust-side dynamic pressure generating groove is provided in at least one of the one end face of the shaft and the thrust bearing member, wherein at least two radial-side dynamic pressure generating grooves for performing an action of making a lubricant flow to the thrust bearing member are provided in at least one of an inner circumferential surface of the bearing hole of the sleeve and an outer circumferential surface of the shaft, and a lubricant pool portion, which is larger than a clearance between the sleeve and the shaft in the two dynamic pressure generating grooves and not confronting outside, is provided between the two dynamic pressure generating grooves, and wherein a pressure regulating hole is provided at a central portion of the one end face of the shaft confronting the thrust bearing member, and the pressure regulating hole communicates with the lubricant pool portion.