| 摘要 |
PURPOSE:To realize a control of the tape contact pressure at a constant level regardless of a variation of the friction resistance, by providing a means to detect the contact pessure between a rotary head drum and a tape and a means to control the rotational torque of a reel with the output of the said detecting means. CONSTITUTION:The output of a contact pressure detecting device 10 provided to a rotor 2 having a video head is fed to a detecting circuit 21, and the output of the circuit 21 is supplied to a switch circuit 23 via an amplifier 22. The output of the circuit 23 receives a voltage holding at a holding circuit 24 and is applied to a differential amplifier 25 that compares the voltage of the circuit 24 with the voltage given from a reference voltage source 26. The output of the amplifier 25 is given to a motor drive control circuit 27 that controls the rotational torque of a reel motor 7. As a result, the tape tension is controlled to ensure a constant contact pressure to a dummy head chip 11 of the device 10. |
