AIR FEED WELD GUN WITH RETRACTABLE PISTON

摘要

A blow feed weld gun for welding a nut to a metal substrate is disclosed. The blow feed weld gun has an air feed mechanism and a nut drive mechanism. The nut drive mechanism contains a primary piston assembly located within a cylindrical working chamber. The primary piston assembly is coupled to a first driven piston which is hollow and defines a passage which welding gasses and/or air can be delivered to the threads of a threaded weld nut.