| 摘要 |
<p>PROBLEM TO BE SOLVED: To correctly and rapidly regulate the height of a guide pole without being affected by backlash. SOLUTION: A power transmitting part is provided between a control motor 9 and the guide pole. This device is provided with the position sensor 10 and rotary encoder 8 generating a reference positional signal when the height of the guide pole coincides with the reference height, and the displacement of the guide pole is stopped at the time of generating the reference positional signal. The enumerated value of the number of output pulses generated from the rotary encoder is stored after the time point generating the reference positional signal. The guide pole is displaced in the opposite direction, the number of output pulses generated from the rotary encoder 8 is obtained until the time point generating the reference positional signal of the position sensor 10 from the time point starting displacement, and the enumerated value of the difference with the stored enumerated value is stored as the enumerated value corresponding to the backlash of the power transmitting part. The quantity of displacement of the guide pole is corrected using the enumerated value corresponding to the backlash of the power transmitting part at the time of recording/reproducing operation.</p> |
