| 摘要 |
<p>PCT No. PCT/SE87/00405 Sec. 371 Date Mar. 17, 1989 Sec. 102(e) Date Mar. 17, 1989 PCT Filed Sep. 9, 1987 PCT Pub. No. WO88/02804 PCT Pub. Date Apr. 21, 1988.A safety device, particularly intended to be used in roll-up doors to cause reversal of the door closing movements in case an obstacle obstructs the path of movement of the door. The device comprises at least a couple of photoelectric cells which are arranged at a certain distance from the closing edge of the door leaf in alignment with the door leaf on a support arm which is displaceable in the direction of closing of the door.</p> |
