| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a shaft-fixed type fluid dynamic-pressure bearing device having a bearing sleeve made of a sintered metal, preventing pressure decrease of an oil film inside a radial bearing gap, and decreasing volume of a sealing space by decreasing the amount of oil. <P>SOLUTION: In a bearing sleeve 8, the porosity in the radial bearing surface regions in the axial direction (a first region H1 and a second region H2) is decreased (to 11% or less), and the porosity in the non-radial bearing surface region (a third region H3) therebetween in the axial direction is increased to be greater than the reduced porosity. <P>COPYRIGHT: (C)2013,JPO&INPIT |
