| 摘要 |
PURPOSE:To detect the end of the tape take-up as soon as the last one turn is taken up by delivering a tape sag signal after comparing the output voltage of a tape tension detecting means with the reference volage. CONSTITUTION:When the quantity of remaining tape becomes small in a take-up mode, a tape end signal is delivered from a tape end detector 1. In this case, a tape T is still wound round both reels and a tension arm A is shifted to a position where the spring force is equal to the tape tension. No tape sag signal is delivered yet from a tape sag detector 2. The termination of the tape T becomes free at a moment when the last turn of the tape T is taken up. Thus the tape tension is set at about 0, and the force of a spring mechanism B overcomes the tape tension. Then the tension arm means A moves to the position where the tape tension is 0, and a potentiometer P delivers voltage. Then a tape sag signal is delivered. A tape take-up detecting circuit 3 delivers a tape take-up end signal. |
