PURPOSE: To independently adjust the cleaning width and the depth of penetration and to perform the optimum welding in accordance with the required quality by fixing a reversed polarity electric current value and a period of a straight polarity electric current and making variable the period of the reversed polarity electric current and the straight polarity electric current value.
CONSTITUTION: In the TIG welding of a aluminum, the reversed polarity electric current value IRP and the period TSP of the straight polarity electric current are fixed and the period TRP of the reversed polarity electric current and the straight polarity electric current value ISP are set variably. Then, the depth of penetration and the width of cleaning are adjusted independently respectively by the straight polarity electric current value ISP and the period TRP of the reversed polarity electric current. A reversed polarity period adjuster 8 is provided to a DC power source circuit to adjust only the reversed polarity period for said adjustment and the straight polarity electric current value ISP is changed by a reference signal ES of a reference signal setter 10. As a result, the width of cleaning and the depth of penetration are adjusted independently and the optimum welding in accordance with the requirement can be performed.
HONDA KEIZO
YAMAMOTO HIDEYUKI
TERAYAMA KIKUO
DAIHEN CORP