Patent ID: 8378251

Claim:
A two-electrode arc welding device, comprising: a power supply that outputs a straight-polarity voltage of low electrical potential relative to a welding base metal and a reverse-polarity voltage of high electrical potential relative to the welding base metal and having a different electrical potential than the straight-polarity voltage; a straight-polarity non-consumable electrode to which the straight-polarity voltage output from the power supply is applied, and causes an arc to form by a voltage occurring between a leading end thereof and the welding base metal; and a reverse-polarity non-consumable electrode to which the reverse-polarity voltage output from the power supply is applied, and causes an arc to form by a voltage occurring between a leading end thereof and the welding base metal, wherein the straight-polarity non-consumable electrode and the reverse-polarity non-consumable electrode are disposed to be separated by at least a minimum distance at which an arc will not occur therebetween, and respectively cause an arc to the welding base metal to form.