FLUID DYNAMIC BEARING DEVICE

摘要

In a bearing sleeve (8), the invention decreases (to 11% or less) the porosity in the radial bearing surface regions in the axial direction (a first region (H1) and a second region (H2)), and increases the porosity in the non-radial bearing surface region (a third region (H3)) therebetween in the axial direction to be greater than said porosity.