| 摘要 |
<p>PURPOSE:To keep tension to an optimum value, by inputting a change in output resistance of a distortion meter caused with the press-contacting of a tape to a bridge, detecting the output change of the bridge and comparing the change with an initial set voltage and controlling the reference voltage. CONSTITUTION:An output of a high frequency oscillator 12 drives detectors 10 and 13. The detector 10 is a distortion meter detecting the pressing force of a tape and forms one side of a bridge and the output voltage of the bridge is fluctuated depending on the press-contacting force. This voltage variation is amplified 11 and synthronizingly detected 13, the output is compared 14 with an initial set voltage V01 and the output of the comparator 14 is given to a reference voltage V02 providing the optimum tape tension to control a supply side capstan motor 15. The changeover of tape speed is made by switching the reference voltage V03 for a speed changeover section 16, initial voltage and reference voltage changeover sections 17 and 18, and a take-up side capstan motor 19. Thus, the tape tension at each tape speed can be kept constant.</p> |
