| 摘要 |
PURPOSE:To reliably screw a thread to a predetermined height by comparing and judging the thread tightening height with a contact piece provided on a drive shaft and a switch fitted to a detecting lug and stopping the rotation of a motor driver as soon as the switch is operated. CONSTITUTION:A drive shaft 13 is adjustably fitted with a contact piece 14, is connected to a rotary shaft system, and is fitted with a bit 7 at one end. A connector 15 slidably guides a detecting lug 17, which is fitted with a spring 18, and a block 19 is fitted at one end. The block 19 is fitted with a swingable lever 20, a lever spring 21 energizing the lever 20 in one direction, and a switch 22 detecting the displacement of the lever 20, and is moved in one body with the detecting lug 17. The bit 7 is lowered through a Y-pipe 23 and is engaged with the head cross hole of a thread S to start screwing the thread S into a work W, and the contact piece 14 is lowered to hit the lever 20, then the switch 22 is operated. |
