| 摘要 |
PURPOSE:To improve the workability and to control the oscillating movement by constituting a motor into a single module, using an oil-impregnated sintered bearing to the lower part of a driving shaft and by installing a balance weight at the bottom end of the driving shaft. CONSTITUTION:At the top end of the driving shaft of a spindle motor 10 is fixed a spindle cup 21 to put on an optical disc 16 fixedly, while a yoke 23, a magnet 24, and an iron base 29 forming a magnetic circuit are provided right under the spindle cup. A spindle motor is constituted into a single module. On the other, a driving shaft 20 is installed to a holder 25 with a ball bearing 27 and an oil-impregnated sintered bearing 28, with which the center of the oscillating movement of the motor 10 is put into the position as high as the ball bearing. Further, a balance weight 31 is fastened with screws at the bottom end of the driving shaft 20. As the center of balance of the motor 10 is in keeping with the center of the oscillating movement, the oscillating movement of the motor 10 can be prevented. |
