| 摘要 |
PROBLEM TO BE SOLVED: To maintain a stable welding condition even if an electrode negative polarity current ratio is set at a large value, in consumable electrode AC pulse arc welding.SOLUTION: A base current is conducted during an electrode negative polarity base period, and an electrode negative polarity peak current Ipn is conducted during an electrode negative polarity peak period Tpn; further a peak current is conducted during an electrode positive polarity peak period, and the base current is conducted during an electrode positive polarity base period. When short circuit occurs during the electrode negative polarity peak period Tpn, and a value correlating to the droplet size at the time of occurrence of the short circuit is lower than a reference value, the current during the short circuit period is increased, and when the value correlating to the droplet size is equal to or higher than the reference value, the period is switched to the electrode positive polarity peak period at the time of occurrence of the short circuit. Thus, since smooth droplet transfer can be performed regardless of the droplet size, stable welding condition can be maintained. |
