| 摘要 |
PURPOSE:To down a spindle pin precisely and to position a center hub on a fitting reference surface precisely by forming a vent on the spindle formed like a stop ended cylinder and discharges air inside the center hole of the spindle freely. CONSTITUTION:A magnetic disc 10 fixing the center hub 9 on its center is inserted and the spindle pin 4 is inserted into the center hole 9a of the center hub 9, the taper-like tip of the spindle pin 4 is precisely positioned and inserted into the center hub 9 and the spindle pin 4 is downed against the spring force of a spring 5. At that time, air inside the center hole 3b is discharged from the vent 12, so that the pressure is not increased, the center hub 9 is precisely positioned on the upper surface of a flange 3a of the spindle 3 which is the fitting reference surface, and the turning force is transmitted under the state that the center hub 9 is precisely centered together with a hub press 11 to be downed. |
