| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-reliability and high-safety emergency stop device for a drive source that achieves constant monitoring of an emergency stop circuit including an emergency stop switch. SOLUTION: The emergency stop device is provided with a coil conduction circuit 18, which includes a series circuit composed by connecting a coil 2a of an electromagnetic contactor MC1 and a light-receiving element of a photocoupler 26 in series, and the emergency stop circuit 20 in which a contact 6a of the emergency stop switch 6, a resistor 25, a fuse 24, and a light-emitting element of the photocoupler 26 are connected in series. When the fuse 24 is melted down due to a short circuit or a ground fault in the emergency stop circuit 20, the coil 2a of the electromagnetic contactor MC1 is not excited due to the non-conductive coil conduction circuit 18 since the light-receiving element of the photocoupler 26 does not receive light due to the non-conductive light-emitting element of the photocoupler 26. As a result, contacts 2 of the electromagnetic contactor MC1 are changed to an open state from a closed state so as to stop an operation of a motor 4. COPYRIGHT: (C)2008,JPO&INPIT
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