DYNAMIC PRESSURE GAS BEARING, MANUFACTURING METHOD FOR DYNAMIC PRESSURE GAS BEARING, SPINDLE MOTOR, RECORDING DISC DRIVE, AND POLYGON SCANNER

摘要

PROBLEM TO BE SOLVED: To provide an inexpensive dynamic pressure gas bearing with high productivity while securing bearing performance. SOLUTION: In the dynamic pressure gas bearing 115, a dynamic pressure bearing part 118 generating a dynamic pressure by relative rotation of a sleeve and a shaft is composed of a minute gap 180 formed between a wall surface of the sleeve 150 and a wall surface of the shaft 120, and gas existing in the minute gap. The dynamic pressure bearing part has a first radial dynamic pressure bearing part 181 and a second radial dynamic pressure bearing part 186 adjacent to each other via a gas intervening part 191. The shaft has a ceramic made first shaft 121 and second shaft 122 composing each of the first radial dynamic pressure bearing part and the second radial dynamic pressure bearing part. The first shaft and the second shaft are mutually fixed so that a gap 190 opening to the gas intervening part and communicated with outside air is secured between both shafts. COPYRIGHT: (C)2004,JPO