| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a non-contact switch and a safety controller suitable to construct a safety circuit. <P>SOLUTION: The safety controller 4 and a sensor part 10b of the non-contact door switch 10 are connected by a single signal line. The sensor part 10b outputs, to the safety controller 4, a detection pulse signal formed by delaying timing of an input pulse signal of a prescribed pattern from the safety controller 4 in a detection state that approach of an actuator 10a is detected by door closing, stops the output of the detection signal in a non-detection state that the approach of the actuator 10a is not detected by door opening, and forcibly draws a different portion in a level of the pulse signal into a low level when the signal line is short-circuited to detect the short circuit as a signal different from the prescribed pattern. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
