Patent ID: 6698931
Filing Date: 2004-03-02
Classification: F16C,H02K

Abstract:
A dynamic pressure-type liquid bearing unit, comprising:a thrust plate, a sleeve, a stationary shaft having an axial direction and a thrust bearing, wherein: the thrust plate is attached to one end side of the sleeve, the sleeve is rotatably supported on the stationary shaft, and the thrust bearing is attached to the stationary shaft and is located between the sleeve and the thrust plate leaving a gap around the thrust bearing, unsymmetrical herringbone-shaped dynamic pressure-generating grooves located on at least one part of the outer circumferential surface of the stationary shaft and on the inner circumferential surface of the sleeve that is opposed to the outer circumferential surface of the stationary shaft, lubricating oil located in a gap between the stationary shaft and the inner circumferential surface of the sleeve and in the gap around the thrust bearing, a first capillary sealing portion of the stationary shaft having a tapered surface along the axial direction is located between one end of the stationary shaft and the sleeve, and a second capillary sealing portion having a tapered surface along the axial direction of the stationary shaft is located between the other end of the stationary shaft and the thrust plate, and groove portions comprising indentations having a bottom surface at a predetermined depth for removing air are located on the outer surface of the stationary shaft between the first capillary sealing portion and the second capillary sealing portion, for ducting air for discharge via the second capillary sealing portion.