| 摘要 |
PURPOSE:To improve the holding accuracy of a recording medium by a driving device by driving a driving means for rotating the recording medium at rotational frequency necessary for recording and reproducing and the rotational frequency sufficient for holding the recording medium. CONSTITUTION:When a recording disc 1 is inserted into the device, a detecting means 8 is actuated and a starting signal is inputted from an arm opening/closing detecting circuit 13 to a spindle motor driving circuit 11 and a recording disc rotation detecting circuit 14 on the basis of an output from the means 8. Consequently, a spindle motor 12 is rotated, and since the driving frequency corresponds to the output frequency of a frequency dividing circuit 16, the rotation of the spindle motor 12 is increased up to rotational frequency (n). While being automatically centered by the rotation of a spindle 2, the recording disc 1 is held by a collet 4. When a pulse is outputted from a rotation detecting means and that the rotational frequency of the circuit 14 is (n) is detected, a switch 10 is changed, the output of an oscillator 15 is supplied to the driving circuit 11 and the rotational frequency of the motor 12 is increased up to steady rotational frequency N. Thus, the holding accuracy of the recording medium by the collet 4 is improved.
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