Patent ID: 6382492
Filing Date: 2002-05-07
Classification: B25C

Abstract:
A trigger device for a box nailing machine, the box nailing machine including a piston driving a nail, a cylinder accommodating the piston, a main selector valve for introducing compressed air into the cylinder and discharging the compressed air from the cylinder, a start operation valve for operating the main selector valve, a trigger lever and a contact arm, said trigger device comprising:a trigger switch operated by the trigger lever, a contact switch operated by the contact arm; an electromagnetic valve serving as the start operation valve; a logical circuit for applying a drive current to said electromagnetic valve when both said trigger switch and said contact switch turn on; and control means including a timer having a predetermined time period that begins with a trigger signal of said trigger switch and resets upon release of said trigger switch, said control means prohibiting the drive current from applying to said electromagnetic valve when said timer counts the predetermined time period.