Patent ID: 8215842
Filing Date: 2012-07-10
Classification: F16C,G11B,H02K,Y10T

Abstract:
1. A fluid dynamic pressure bearing comprising: a shaft arranged along a central axis, the shaft including a stepped surface arranged on an outer circumferential portion thereof; an annular member fixed to the shaft, the annular member including a lower surface extending radially with respect to the central axis, the lower surface including an inner edge portion arranged to make contact with the stepped surface; a sleeve including an upper surface axially opposed to the lower surface of the annular member; a lubricant arranged between the shaft and the sleeve and between the annular member and the sleeve; and a lubricating film on the lower surface of the annular member at least over a region extending radially outwardly of the inner edge portion of the lower surface; wherein the lower surface of the annular member includes an exposed metal surface arranged to make contact with the stepped surface.