| 摘要 |
The device comprises a frame 1 and a shaft 5 mounted on bearings 6, 7 and equipped with a lever 9 operating a barrier 2 fastened to a support fixed to the end of the shaft 5. The lever 9 is driven by a rack 11 - and - pinion 12 assembly keyed on the output shaft of a geared motor 14; the rack 11 is guided in an oscillating block 25 mounted on the shaft 13; a safety device 16 is interposed between a ball joint 15 mounted on the end of a lever 9 and the end of the rack 11, and it comprises a displacement sensor which interrupts the electrical supply to the geared motor when an obstacle to the closing of the barrier is encountered. The ends of travel of the lever 9 are monitored by means of displacement sensors 17, 18, 19 detecting the passage of the said lever 9. <IMAGE> |
