| 摘要 |
PURPOSE:To perform the adequate control of tension with a magnetic tape without receiving the effect of a reel winding diameter of the tape and with no secular change, by applying the braking force to the supply side of the tape with an electromagnetic brake. CONSTITUTION:A piezoelectric ceramic 26 serving as a pressure detecting means is provided between head cores 18 and 19 via a slight gap 24. A bounded guide part 16 applies the braking force corresponding to the output signal value fed from a power amplifier 48 to a rotary cylinder 70. As a result, the tension of a magnetic tape 10 is always controlled by servo to the set value at the part of a magnetic head 12. Thus the head 12 can record and reproduce an accurate signal to the tape 10. Thus no effect is exerted from the winding diameter and the disturbance winding state of the tape 10. In such a way, the mechanical wear and the secular change of the tape tension is eliminated. |
