CONTACT SPOT WELDING PROCESS CONTROL METHOD Russian patent published in 1995 - IPC

FIELD: welding. SUBSTANCE: method involves measuring parameter of mobile electrode during current pulse supply process; integrating the value and, thus, determining parameter to be controlled, which is proportional to integral of electrode displacement current value; comparing it with predetermined value. Method is characterized in that during welding, parameter to be controlled is determined as a value proportional to mobile electrode displacement value, as well as in that welding current pulse is increasing from the initial value, which is set to be equal to half the welding current value, at which predetermined core diameter is obtained provided that diameter value is not regulated during welding process and the same electrode compression and current pulse time values are used. Welding current values increasing from initial value are set by ratio recited in Specification. Parameter proportional to displacement of mobile electrode is controlled. When predetermined value is obtained and indicated by initiation of melting of metal in contact, increase in supplying of welding current is stopped and current value is maintained at constant level. When parameter, proportional to electrode displacement current value integral, and core diameter reach predetermined value, welding current is cut off. EFFECT: improved quality of joints by increased reliability of contact spot welding process control method. 5 cl, 1 dwg