| 摘要 |
PURPOSE: To prevent the generation of such an accident of falling of a cutting edge or finger cutting off by providing a means for sounding an alarm when a detecting means for detecting the separation of the cutting edge from the cutting edge receiving side is in action for the fixed time or more. CONSTITUTION: A time constant of a capacitor C1×resistance R2 is set to about three minutes, and when a cutting edge 3 cuts paper and returns into a contact state with a switch pressing fitting 7 within three minutes, a micro switch 11 is switched on, and the capacitor C1 is rapidly charged through the resistance R1. The charge of the capacitor C1 holds the input of an inverter IC1 to an H-level and the output of IC2 to an H-level, so that a buzzer BZ of load does not sound. However, when the separated state of the cutting edge 3 and switch pressing fitting 7 lasts for three minutes or more, the charge of the capacitor C1 is discharged in the meantime to switch the input of the inverter IC1 to an L-level and the output of IC2 to an L-level, and a current is applied to the buzzer BZ of the load to sound the buzzer.
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