| 摘要 |
PROBLEM TO BE SOLVED: To provide a spindle motor having small wobble of a shaft and long life despite thin wall thickness.SOLUTION: A spindle motor is equipped with: a shaft inserted into a sleeve and rotates to a base; a hub that integrally rotates with the shaft; a radial dynamic pressure bearing portion formed between the shaft and the sleeve; a flange portion provided in a protruded manner in a radial direction for an outer circumference of the sleeve; an annular wall portion provided in a protruded manner for the hub in a direction surrounding the sleeve; and an annular thrust ring which is adjacent to an axial direction of the flange portion and the shaft, and fixed to the inner circumference of the wall portion. Then, the motor is equipped with a lubricant filling section which includes a gap between inner circumference surface at least from the top portion to a closed end of the sleeve and the shaft, a gap between the sleeve and the hub, a gap between the sleeve and the thrust ring, a gap between the thrust ring and the sleeve, and has only one open end which is formed so as to surround the radial dynamic pressure bearing portion at a position closer to the closed end of the sleeve than an end portion on the base side of the thrust ring in a rotational axis direction. |
