摘要 |
A fluid dynamic bearing apparatus having an increased a value of tolerance for a moment load is provided. A cylindrical sleeve portion 8 is fixed to the inner periphery of the housing 7 whose both ends are open, and a shaft member 2 is further inserted at the inner periphery of the sleeve portion 8. Sealing portions 9, 10 are fixed to the shaft member 2 in the manner of nipping the sleeve portion 8 from both sides in the axial direction, and sealing spaces S1, S2 having the oil level of a lubricating oil are formed between the outer circumferential surfaces 9a, 10a of the sealing portions 9, 10 and the inner circumferential surface 7a of the housing 7. The radial bearing gap between the inner circumferential surface 8a of the sleeve portion 8 and the outer circumferential surface 2a of the shaft member 2 is formed and thrust bearing gaps are formed between the end faces 9b, 10b of the sealing portions 9, 10 and the end faces 8b, 8c of the sleeve portion 8 opposing these to support the shaft member 2 in a non-contact manner in the radial direction and in the thrust direction by the hydrodynamic effect of the lubricating oil produced in each bearing gap.
|