Patent ID: 7186028

Claim:
A hydrodynamic bearing device, comprising: a shaft relatively rotatably inserted into a bearing hole of a sleeve; a radial bearing surface having dynamic pressure generating grooves and formed on at least one of an outer peripheral surface of the shaft and an inner peripheral surface of the sleeve; a gap formed between the shaft and the sleeve and filled with a working fluid; and a rotor hub located at a rotating side and supported rotataly with respect to a base at a fixed side, wherein the shaft fixed to the rotor hub or the base is constituted of high manganese chrome steel or stainless steel, and the entire sleeve fixed to the base or the rotor hub is constituted of sintered metal comprising metal particles including at least 60% by weight of iron or copper, and resin, metal or water glass is impregnated in pores existing on a surface of the sintered metal and cured.