Abstract: For a tapered material having a plate thickness changing in a longitudinal direction to be roll-molded with stability by means of a simple and inexpensive configuration, a roll-molding device includes two parallel roller shafts, fixed rollers concentrically disposed with respect to one of the roller shafts, floating rollers disposed to be capable of being eccentric with clearances with respect to the other one of the roller shafts, facing the fixed rollers, and molding a belt-shaped metallic material pinched between the fixed rollers and themselves, a pressing roller abutting against an outer circumferential portion on the side opposite to points of contact of the floating rollers with the fixed rollers, and actuators pressing the floating rollers toward the fixed rollers via the pressing roller.

Abstract: A box nailing machine includes a piston within a cylinder to drive a nail. A main selector valve introduces compressed air into the cylinder and discharges the compressed air from the cylinder. A start operation valve operates the main selector valve. A trigger device for the box nailing machine comprises: a trigger switch operated by a 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 the electromagnetic valve when both the trigger switch and the contact switch are turned on; and a controller which includes a timer with a predetermined time limit. The timer is started in accordance with a trigger signal of the trigger switch and prohibits the drive current from the electromagnetic valve when the timer counts the predetermined time period. The timer is reset upon release of the trigger.