Control device for resistance welder, energization status monitoring method for welded parts, and quality judgment method

摘要

PROBLEM TO BE SOLVED: To reduce the cost of monitoring a change in the total resistance value of a welding current path, and to reduce the cost of determining the quality of a welded portion and monitoring the electrode shape. SOLUTION: A control device 20 of a resistance welding machine (welding robot 10) converts a direct current into an alternating current and supplies it to a welding transformer 15, and a current value supplied from the inverter circuit 42 to the welding transformer 15. The current detection unit 44 to be measured, the current control circuit 43 that sets the pulse width WP based on the current value measured by the current detection unit 44, and the recording unit that records the parameters related to the pulse width WP set by the current control circuit 43. With 34. [Selection diagram] Fig. 1