Patent ID: 8338750

Claim:
A control method for AC pulse arc welding performed upon application of cyclic AC welding current to a welding wire and a base metal, one cycle of the welding current including an electrode negative polarity period and an electrode positive polarity period subsequent to the electrode negative polarity period, the method comprising the steps of: applying an electrode negative polarity base current for forming a droplet on an end of the welding wire and a subsequent electrode negative polarity peak current for making the droplet bigger during the electrode negative polarity period, the electrode negative polarity base current having an absolute value smaller than a first critical value, the electrode negative polarity peak current having an absolute value greater than the first critical value; and applying an electrode positive polarity peak current during the electrode positive polarity period that causes the droplet made bigger by applying the subsequent electrode negative polarity peak current to transfer from the welding wire to the base metal, the electrode positive polarity peak current having a value greater than a second critical value.