Method of determining deterioration of pressurizing performance of spot welding gun

摘要

A method of determining deterioration of pressurizing performance of a spot welding gun which has a movable side electrode tip moved by driving force of a servo motor and a fixed side electrode tip in opposition to the movable side electrode tip and which carries out welding of a work piece under pressurized state between the movable side electrode tip and the fixed side electrode tip, the method having: obtaining reference data that reflect a dynamic state of the servo motor when the movable side electrode tip is moved in a straight line in a predetermined operational mode without bringing the movable side electrode tip into contact with the work piece in the case where the movable side electrode tip is operated normally and the wok piece is pressurized by a specified pressurizing force; performing data processing on the reference data to extract a reference characteristic value.