Welding device and method for moving contact assembly of contactor

The welding device comprises a main beam frame which is driven by a driving source to move up and down, two upper supporting frames are arranged in the main beam frame in a sliding mode, the upper supporting frames can be selectively fixed to the main beam frame through bolts, sliding holes are formed in the upper supporting frames, and the upper supporting frames can be fixed to the main beam frame through bolts. A ceramic base is slidably connected into the sliding hole and comprises a connecting rod located in the sliding hole, the connecting rod penetrates through the bottom of the upper supporting frame and is connected with a connecting sleeve, and an upper ceramic pressing rod is fixed into the connecting sleeve; the upper portion of the upper ceramic pressing rod is sleeved with a damping spring, the two ends of the damping spring are fixed between the lower end face of the upper supporting frame and the upper end face of the connecting sleeve respectively, supporting bases are oppositely arranged bel