| 摘要 |
PURPOSE:To prevent the generation of a penetration defect to base metals by online correcting the deviation of the preset weaving width of a welding torch. CONSTITUTION:A welding current value considerably increases only in the welding torch 3R approaching the base metal 1R side when the welding torch 3 is subjected to weaving in the cross direction with respect to a welding direction by a weaving driving part 5. The max. current value in this stage is latched to a holding circuit 10 for the max. value at the weaving end by the signal from a position detector 4 of the welding torch 3 and is compared with the welding current latched and held in a holding circuit 11 for a DC component value by a comparator 12, by which the difference therebetween is determined. The difference between both current values is compared with a reference value 14 in a differential amplifier 13 and the driving part 5 is driven by a control signal from an instruction part 15 to change the weaving width of the torch 3 according to the detect differential value within the certain range of the weaving width from the base metal 1R. |
