Patent ID: 8033732
Filing Date: 2011-10-11
Classification: F16C,G11B

Abstract:
1. A hydrodynamic bearing device, comprising: a shaft; a sleeve member that has a bearing hole including an open end and a closed end, and that is disposed in a state in which the shaft is inserted in the bearing hole with a microscopic gap in between, and in which the sleeve member is capable of rotation relative to the shaft; a lubricant that fills the microscopic gap; a bearing portion that has a radial bearing portion supporting the shaft and the sleeve member in a radial direction of the shaft via the lubricant, and a thrust bearing portion supporting the shaft and the sleeve member in an axial direction; and a bearing seal portion that is disposed on an opened end side of the bearing portion, and suppresses leakage of the lubricant from the opened end by capillary force working between the shaft and the sleeve member, wherein a rotor hub member formed from a substantially circular top plate and a cylindrical wall hanging down from the top plate is attached on an open end side of the shaft, the bearing seal portion is formed by an outer peripheral surface of the sleeve member and an inner peripheral surface of the rotor hub member, and wherein a value of a function P