Tig welding device

A TIG welding device comprising:

• a cylindrical torch body removably attaching and holding a torch electrode therein;
• a welding power supply for feeding a current to flow in a closed circuit including the torch electrode and a welding workpiece either for current application between a tip of the torch electrode and the welding workpiece or for generation of arc in a touch start system;
• a linear movable part movable in a vertical direction;
• a driving unit for moving the linear movable part in a straight line;
• an external terminal attached to a lateral surface or an upper end of the torch body and electrically connected to the torch electrode through a conducting path in the torch body;
• a current relay provided at the linear movable part, the current relay including a first current relay terminal where a welding current feeding line from the welding power supply terminates, and a second current relay terminal electrically connected to the first current relay terminal through a fixed conductor;
• a displaceable or deformable bridging conductor provided between the second current relay terminal of the current relay and the external terminal of the torch body;
• a torch nozzle attached to a lower end portion of the torch body for ejection of shielding gas toward the welding workpiece;
• a gas inlet port attached to the lateral surface or the upper end of the torch body and communicating with the torch nozzle through a gas path in the torch body;
• a gas relay provided at the linear movable part, the gas relay including a first gas relay port where a gas feeding line from a shielding gas feeding part for feeding the shielding gas terminates, and a second gas relay port communicating with the first gas relay port through a fixed gas chamber or a fixed gas path;
• and
• a displaceable or deformable bridging tube provided between the second gas relay port of the gas relay and the gas inlet port of the torch body.