| 摘要 |
PROBLEM TO BE SOLVED: To prevent a discharge of an arc from any other points than an electrode tip end and improve an arc starting property by making the nozzle composed of such a heat-resisting material as ceramic or glass and the like, and sealing an active electric portion other than the electrode tip end. SOLUTION: A collet 2 and a torch nozzle 3 are attached to a torch 1, and an inner nozzle is attached to the collect 2. An electrode 5 is stuck out from the center of these parts. An inert gas discharged from the collet 2 touches only to the tip end portion of the electrode 5, passing through a gap between the torch nozzle 3 and the inner nozzle 4. A hole diameter of the center portion of the inner nozzle 4 is made to be a degree of -0, +0.1-1 mm against a diameter of each electrode 5. Because of this constitution, as oxide film and a stain do not stick to other place than the electrode tip end, and even when they do, an accidental fire can be prevented as it is removed by a self electrode cleaning at the time of arc discharge. Also an active electric part is limited to only the electrode tip end, and steady welding is made possible because the arc discharge always takes place from the tip end of the electrode. |
