| 摘要 |
PURPOSE:To improve the positioning precision of the disk center and to increase track density by providing a projecting shaft in the center of a turntable, fixing a rubber ring around the shaft to hold the center opening of a hub by the rubbing ring. CONSTITUTION:The projecting shaft 11 is provided pierce the turntable 6 and the forward end of circumference of the shaft 11 is wound with the rubber ring 13. The external diameter of the rubber ring is a little bit greater than the internal diameter of the center opening 3 of the hub 2; and the hub 2 is pressed in the rubber ring 13 by a pressuring shaft 8 and the rubber ring 13 shrinks uniformly to hold the center opening and to align disk. The turntable 6, disk 1, and pressuring shaft 8 are rotated by a rotation driving body 12. Consequently, the positioning is carried out with high precision, and the track density of the disk is increased to obtain the disk having a large storage capacity. |
