FLUID DYNAMIC-PRESSURE BEARING MECHANISM, MOTOR, RECORDING DISK DRIVING DEVICE, AND METHOD FOR PRODUCING FLUID DYNAMIC-PRESSURE BEARING MECHANISM

摘要

PROBLEM TO BE SOLVED: To accurately and easily check the position of the interface of a lubricating oil in a fluid dynamic pressure mechanism utilizing a fluid dynamic pressure.;SOLUTION: The bearing mechanism 4 of a motor 1 used in a recording disk driving device includes a shaft 41, a bearing 42 being part of a rotor body and seal members 43a and 43b. A lubricating oil 10 is filled between the shaft 41 and the bearing 42. A tapered gap 45 whose width is gradually extended toward the opening side is formed between the outer inclined surface 4112 of the annular member 411 of the shaft 41 and the inner surface 4321 of the seal member 43. The diameters of the outer inclined surface 4112 and the inner surface 4321 are gradually reduced toward the opening side. The interface 11 of the lubricating oil 10 is formed in the tapered gap 45. The seal member 43 has a light translucency, whereby the position of the interface 11 of the lubricating oil 10 can accurately and easily be checked from the diametrical outside.;COPYRIGHT: (C)2010,JPO&INPIT