| 摘要 |
To achieve a good welding state by stabilizing a feeding state of a welding wire, in arc welding of alternating feeding of the welding wire between a forward feeding and a reverse feeding periodically according to a push-pull feeding control. The welding is performed in a manner of feeding the welding wire according to the push-pull feeding control using a push-side feeding motor which rotates in the forward feeding direction at a constant feeding rate based on a push feeding-rate correction signal Ps and a pull-side feeding motor which alternates a forward feeding rotation and a reverse feeding rotation periodically based on a pull feeding-rate setting signal Fr, and generating short-circuiting periods and arc periods. An average feeding rate Fad of the pull-side feeding motor is detected and the push feeding-rate correction signal Ps is corrected to the detected average feeding rate Fad of the pull-side feeding motor. Consequently, even if a feeding resistance changes and hence the average feeding rate Fad of the pull-side feeding motor changes, as a feeding rate Fd of the push-side feeding motor is controlled to follow the average feeding rate, the feeding state of the welding wire becomes stable. |
