| 摘要 |
<p>PURPOSE:To reduce the over-wrapping amount of a tape and to prevent a drum motor and a motor driving circuit from being destroyed due to an overcurrent by applying current limiter on the motor driving circuit after completing servo lock on the drum motor. CONSTITUTION:When the drum motor 1 is set at a constant rotating state and the servo lock is completed, a current limiter control means 4 detects the fact, and starts the operation of the current limiter of the motor driving circuit 2. Therefore, a motor driving current is suppressed compulsively less than a limiter current value after the servo lock is completed, and the driving current can be prevented from being increased exceeding the limiter current value even when an accident in which the tape stuck occurs and the motor driving current is increased. Thereby, the start-up torque of the drum motor 1 can be decreased, and the wrapping amount of the tape can be decreased due to the accident in which the tape is stuck, and also, it is possible to prevent the drum motor 1 or the motor driving circuit 2 from being destroyed due to the overcurrent.</p> |
