Tungsten inert gas arc striking device

Claim 1

Apparatus including an alternating current welding power supply for striking and restriking a tungsten inert gas arc to produce an AC welding arc voltage across a pair of welding electrodes comprising a. rectifier means for rectifying said arc voltage, b. comparator means for comparing the rectified arc voltage with a reference voltage, c. trigger pulse generator means coupled to said comparator means for producing a trigger pulse when said rectified arc voltage corresponds to said reference voltage, d. a kick voltage generating circuit including 1. a discharge switch having first and second electrodes opposing each other and a discharge starting electrode disposed adjacent said first and second electrodes, 2. a capacitor, and 3. first and second electromagnetically coupled coils; said first and second discharge switch electrodes, said capacitor and said first coil constituting a closed circuit, and 4. means for charging said capacitor; e. means for applying said trigger pulse between said discharge starting electrode and one of said first and second discharge switch electrodes, the charge in said capacitor being discharged through said first and second electrodes of said discharge switch and said first coil to induce a kick voltage across said first coil, and f. means connecting said second coil in series with said welding power supply and said welding electrodes, the kick voltage induced across said first coil being superimposed on the welding power supply voltage through said second coil for striking and restriking said welding arc.