PROTECTIVE DEVICE OF NON-CONTACT FEEDER SYSTEM

摘要

A thermosensitive wire (15), including a pair of phosphor bronze round wires which cause a short-circuit when the ambient temperature reaches a predetermined level or higher, is laid along an induction line (14), and a protective device (25) including a DC power supply unit (33) for applying a DC voltage and a meter relay (35) for detecting that the thermosensitive wire (15) has caused a short-circuit is provided on both ends of the thermosensitive wire (15). An alarm output (35A) of the meter relay (35) is outputted to a high-frequency generating circuit (24) so as to shut down a high-frequency current to be supplied to the induction line (14). With this structure, even when a metal such as a tool made of iron is erroneously set near the induction line (14), the heating thereof may be detected by using the thermosensitive wire (15) and the high-frequency current flowing through the induction line (14) may be shut down. Thus, fire accidents such that the induction line (14) is heated and burnt by further heating may be prevented.