| 摘要 |
<p>PURPOSE:To prevent damaging of magnetic tape by sending out a tape running abnormality signal when the revolving direction of reels is opposite from the tape running direction and tape buffer quantity does not decrease. CONSTITUTION:When the portion of deflection or double winding comes to the magnetic tape 4 wound to a reel 1, this is suddenly let off and therefore a tension arm 5 starts rotating rapidly in the counterclockwise direction and stops at a stopper. Hence, a tension arm rotating direction detector 7 sends an inversion and stop signal to a judgement circuit 12. A reel motor 2 produces torque in the clockwise direction according to the rotation of the arm 5, due to which the reel 1 decelerates the counterclockwise running speed until finally it runs backward in the clockwise direction and therefore the reel rotating direction detector 3 sends a backward running detection signal to the circuit 12. The circuit 12 sends out a tape running abnormality signal based on this signal to a VTR control circuit 13, causing the tape to stop running. Thereby, damaging of the magnetic tape may be prevented before it occurs.</p> |
