Dynamische Gasdrucklagervorrichtung

摘要

Provided is a dynamic pressure gas bearing structure which is applicable to a high-speed rotation driving part such as a hard disk driver or the like and has high rotational accuracy in high-speed rotation. The dynamic pressure gas bearing structure comprises a shaft body (1) and a bearing body (2). When the shaft body (1) and the bearing body (2) are so arranged that central axes (50) thereof are aligned with each other, a substantially cylindrical gap (3) is defined between the outer peripheral surface of the shaft body (1) and the inner peripheral surface of the bearing body (2). The gap (3) has at least one gap change portion whose thickness is changed with respect to a central angle corresponding to the circumference along the outer peripheral surface of the shaft body (1). The gap change rate alpha is at least 1.0 x 10<-4>/ DEG and less than 10.0 x 10<-4>/ DEG .