| 摘要 |
To stabilize arc welding in which feeding of a welding wire is altered between forward feeding and reverse feeding cyclically. A feeding rate Fw of the welding wire is increased in the forward feeding direction during a forward feeding acceleration period Tsu, reduced in the forward feeding direction during a forward feeding deceleration period Tsd, increased in the reverse feeding direction during a reverse feeding acceleration period Tru, and reduced in the reverse feeding direction during a reverse feeding deceleration period Trd. A short-circuit forcibly generating period Tsp is provided between the forward feeding acceleration period Tsu and the forward feeding deceleration period Tsd. During the short-circuit forcibly generating period Tsp, the feeding rate Fw is increased with a change rate larger than that during the forward feeding acceleration period Tsu, and is kept to a predetermined forward feeding peak value when the feeding rate Fw reaches the peak value. Consequently, as short circuit can be forcibly generated during the short-circuit forcibly generating period Tsp, a cycle of short circuit and arc can be stabilized. |
