EXPLOSION FORCE-OPERATED PIN DRIVING DEVICE

PROBLEM TO BE SOLVED: To provide an explosive power operated pin driving implement having a simple constitution and a long life and giving no uncomfortable impact to an operator. SOLUTION: In this explosive power operated pin driving implement constituting a grip part 15 as a part interlocked with a piston 23 movable in a cylinder 18 against the resistance of a liquid medium 21 flow, an impact device 17 has no movable valve part, at least one through hole 24 is provided for the liquid medium 21 to which a pressure is applied during a moving process of a piston, the entering of the piston 23 into the cylinder generates an effective passing section corresponding to the minimum cross section part of the through hole 24 relative to the liquid medium 21 flowing into the front cylinder space 25 so that, when the piston 23 is returned to the original position, it is so constituted that the effective passing cross section of the liquid medium 21 flowing into the rear cylinder space 26 in the region of the through hole 24 becomes smaller than the minimum cross section part.