Powder actuated piston tool with power adjustment

摘要

A power adjustment for a piston-type powder actuated fastener driving tool wherein a tube is slidably disposed in the barrel of the tool, the tube containing the driving piston of the tool. The tube has a radially inwardly extending flange at its breech end which engages a radially outwardly extending surface on the piston. Means for moving the tube axially of the barrel are provided so that the distance between the flange and firing chamber can be varied whereby the gas expansion chamber between the firing chamber and the rear face of the piston can be varied thereby varying the power with which the piston is driven.