| 摘要 |
PURPOSE:To remove the influence of adjacently arranged light invasion sensors, by allowing the adjacently arranged light invasion sensors to transmit and receive light pulses with different patterns while freely performing pattern changing-over. CONSTITUTION:The always opened contacts r1-rn of a light transmitting part 10 and the always opened contacts r11-r1n of a light receiving part 20 are closed through relays by the manipulation of the manual switches 321-32n of a monitoring control part 30 constituting one set of light invasion sensors to select pulse oscillators 111-11n for transmitting light pulses with different patterns and corresponding pulse receivers 231-23n. By this constitution, the adjacently arranged light invasion sensors of a large number of arranged light invasion sensors transmit and receive light pulses with different patterns and the changing-over of said patterns is freely performed while the influence of the adjacently arranged light invasion sensors is removed and the generation of invasion erroneous detection caused by the influence of the adjacent light invasion sensors is prevented. |
