PROJECTION WELDING METHOD, AND PROJECTION WELDING EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To detect and display any explosion occurring by inputting excessive heat in a weld part when welding is carried out utilizing the resistance heat generation. SOLUTION: A projection welding equipment comprises a mean resistance calculator 10 for calculating the mean resistance in a predetermined period after completing the conduction set by a time setting unit 9 by inputting the output signal of a resistance calculator 7 and the output signal of the time setting unit 9, a reference resistance setting unit 11 for setting the reference resistance, a comparator 12 which inputs the output signal of the mean resistance calculator 10 and the output signal of the reference resistance setting unit 11 to compare levels of both output signals, and outputs the explosion occurrence signal when the output resistance of the mean resistance calculator 10 exceeds the reference resistance of the reference resistance setting unit 11, and an explosion display 13 which receives the output signal of the comparator 12 and displays occurrence of the explosion only when the explosion occurrence signal is present. When explosion is detected, it can be displayed, and a weld work 50 in which explosion occurs therein can be removed.