| 摘要 |
<p>PURPOSE:To prevent tape running to prevent damage of the tape for lock release miss by providing a stopper which locks a tension arm and a cam which is rotated together with an arm, which is so operated that a switch may be turned off for the lock state of the stopper, in one body. CONSTITUTION:Guide table 11 and switch cam 12 are fitted to support axis 10, which stands from a mechanical chassis, rotatably, and bracket 14 to fix micro switch 13 for shut-off is fitted to the lower part of axis 10. Tension arm 16 is fixed through table 11 and cam 12, and coil spring 17 is hooked between lower end 15a and pin 16 standing on bracket 14. Three-stage arc cam 18 is formed on the circumference of switch cam 12 and is constituted by cam 18a of the maximum radius, cam 18c of the minimum radius and cam 18b of the middle radius. As a result, the auto- shut-off mechanism is operated for lock release miss to prevent tape running, so that damage of the tape can be prevented.</p> |
