PURPOSE: To reduce inductive reactance drops in a secondary electric conductor by forming secondary side coils of a welding transformer by two windins, and supplying each different welding current generated by said windings to the upper and lower coaxial electrodes, respectively, through two-wire cables of going and returning so that the phases are different from each other.
CONSTITUTION: Welding electrodes 14, 15 are constituted of external electrodes 14a, 15a and internal electrodes 14b, 15b, respectively, and also secondary side coils 11b, 11c of a secondary side coil 11 of a welding transformer 11 are formed by two windings. In this state, a current is supplied to the upper and lower coaxial electrodes 14, 15 through two-wire csbles 12, 11 from the respective windings 11b, 11c so that each phase becomes opposite.
MIURA KIYOUJI
YAMAMOTO TOSHIO
UOMORI AKIYOSHI
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