Patent ID: 8734018

Claim:
A fluid dynamic bearing device comprising: a fixed member; a rotating member; an ester-based lubricating oil; a radial bearing clearance filled with the ester-based lubricating oil; and a radial bearing part that supports the rotating member in a radial direction by an oil film of the ester-based lubricating oil created in the radial bearing clearance, at least any one of the fixed member and the rotating member having a resin member that is in contact with the ester-based lubricating oil, wherein the resin member is formed of a resin composition, the resin composition contain a base resin as one of thermoplastic resin elected from the groups that containing PPS, LCP, PEEK, PBT, and PPSU; carbon fibers; and a binder material binding the carbon fibers each other in a state where the carbon fibers are bundled, the carbon fibers are minced by cutting the carbon fibers in a state where the carbon fibers are bound by the bind material, the binder material is mixed into the resin composition together with the carbon fibers in a state where the carbon fibers are minced, the binder material is not urethane resin, the resin member contains an epoxy resin or a nylon resin as the binder material around the carbon fibers in a state where the carbon fibers are minced.