| 摘要 |
<p>PURPOSE:To prevent the deformation of a roller and the magnetization of a head by permitting a voltage detection circuit to control an action. CONSTITUTION:When a switch 21 impresses a power source 25 to the voltage detection circuit 14, input/output terminals 22, 23 practically become the same potential. Then an electrolytic capacitor C1 in a power source circuit 13 is charged, and the collectors and emitters of switching transistors Trs Q1, Q2 are conducted, which leads an action circuit 12 to enter an action state. When a tape mechanism 11 is reproducing or recording, the voltage impressed to the circuit 14 becomes zero when the switch 21 is turned OFF. That means said voltage is below a reference one, therefore, the terminal 23 of the circuit 4 and the terminal 16 of the circuit 12 come to level '0' to start stop actions. The TrQ2 in the circuit 12 continues an ON action by the capacitor C1 for a while, and the TrQ1 continues an ON state as well. Both of them can be operated until a mechanism 11 is completely stopped by a mechanism action switching plunger 19. Therefore, the deformation of the pinch roller and the magnetization of the head can be prevented.</p> |
