AUTOMATIC WELDING HEAD, ESPECIALLY FOR BUMP NUTS

摘要

1. An automatic welding head for protuberance-bearing nuts (8) of the type comprising a piston (2) fixed with respect to a welding machine slider which co-operates with a cylinder (4) capable of coming to bear against a piece (6) to which a protuberance-bearing nut (8) is to be welded, and a nut feed channel (46) which is fixed with respect to said cylinder, characterised in that : - the piston (2) comprises an axial electrode (24) capable of bearing against the nut (8) by way of a removable welding portion (38), and an intermediate insulating cam (14) which is fixed with respect to said electrode, on the one hand, and - said piston (2) slides against the force of a return spring (22) within said cylinder (4) which contains a nut holding and recentering gripping device (42) whose pivoted arms (44) are capable of being tightened towards or moved away from each other by the intermediate cam (14) upon displacement of the electrode (24) on the other hand.