DOOR OPENING AND CLOSING DETECTION SENSOR USING FARADAY ELEMENT TYPE OPTICAL SWITCH

摘要

PROBLEM TO BE SOLVED: To provide a door opening and closing detection sensor using a Faraday element type optical switch capable of detecting not only the opening and closing of a door to be monitored but the disconnection of an optical fiber as well and having high reliability. SOLUTION: This sensor is so constituted that a magnetic section parts from the Faraday element type optical switch when the door to be monitored is held closed and that the magnet section approaches the optical switch when the door is held open.