Apparatus for monitoring and controlling a welding phenomenon in an electric resistance welding

摘要

An apparatus for monitoring and controlling a welding phenomenon in an electric resistance welding process, which comprises a welding characteristics measuring instrument for carrying out digital measurement of at least one of high frequency welding characteristics, a welding phenomenon monitor circuit for detecting variations in the welding characteristics, and a welding phenomenon controller circuit for automatically adjusting a parameter of a welding power source or other welding conditions, wherein the welding characteristics include an oscillating frequency and an oscillating period of a high frequency used for the welding, and a phase difference between a high frequency voltage and a current. Changes in the welding characteristics occur in correspondence with the occurrence of periodic fluctuations in the shape of the high frequency welding current circuit formed in the material to be welded during high frequency electric resistance welding process.