Clamping device for the wear tube - of an electric arc welding torch and the welding torch using this device

摘要

A clamping device is claimed for a wear tube of an electric arc welding torch in which the tube guides a continuous fusible wire between a contact tube (1') forming part of a lance fixed to one end of a coaxial cable for feeding the wire into the lance and an inlet connector (9') for this coaxial cable distant from the lance. The clamping device comprises a collar (21') in an elastic material crossing the wear tube and some means (23',39) for axially compressing the collar (21'), made up of a wire guide plug (23') mounted on the inlet connector, in a manner such that it is deformed radially to pinch and block the wear tube. The collar (21') is preferably mounted to slide on the wear tube in a manner to come into contact against a surface of the inlet connector during the mounting of the wear tube in the cable across the inlet connector. Pref., the electric arc welding torch for welding under a protective gas incorporating this clamping device is also claimed. USE/ADVANTAGE - The clamping device is used in the wear tube used to guide a fusible filler wire in an electric arc welding torch. The device has a number of advantages:- (a) it allows the correct compression and clamping of a wear tube made in a particularly economic fashion from pieces supplied in long lengths, and consequently without using wear tubes prepared in advance and in due form stocked in the various lengths required; (b) it allows the introduction or removal of a wear tube with a chamfered edge to or from a coaxial cable and consequently is not susceptible to causing it damage.