Cooling structure of resistance welding electrode unit of spot welding gun and spot welding gun equipped with same

摘要

PROBLEM TO BE SOLVED: To provide a cooling structure of resistance-welding electrode part of a spot weld gun which can secure a water-supply amount sufficient to cool even when the resistance-welding electrode part of the spot weld gun is small-sized.SOLUTION: A cooling structure of a resistance-welding electrode part of a spot weld gun, has: a bored water-cooling internal space continuous to the resistance-welding electrode part in a longitudinal direction, inside the electrode part; a bored water supply opening and a drainage opening communicating with the outside from the water-cooling internal space, inside the electrode part; and a water-supply pipe and a drainage pipe inserted and extended in the respective directions of the water supply opening and the drainage opening, the water-supply pipe and the drainage pipe being formed with openings in their side faces and being provided with O rings made of an elastomer on outer periphery surfaces of the pipes, respectively. Here, the water-supply opening and the drainage opening have first fitting parts having a diameter to which the O rings fit and second fitting parts to which the water-supply pipe and the drainage pipe can fit, respectively, but the water-supply pipe and the drainage pipe attached to the water-supply opening and the drainage opening do not have the openings in side faces facing each other.