An indirect spot welding apparatus includes a welding electrode that is brought into pressure contact with one of surfaces of a plurality of plate-shaped members that are objects to be welded in one side in a stacking direction of the plate-shaped members, a ground electrode that is brought into pressure contact with the one of the surfaces in the one side or another one of the surfaces in the other side in the stacking direction in a position shifted from an axial center of the welding electrode, and an opposed member disposed coaxially with the ground electrode to be opposed to the ground electrode so as to hold at least one of the plate-shaped members between the opposed member and the ground electrode, and the welding electrode is mechanically integrated with the ground electrode to be movable in a direction parallel to an axial direction of the ground electrode.

A projection welding electrode holder has a holder body, a holder barrel, and a coned-disc spring. The holder body is configured for attachment to a welding machine and defines a holder body bore. The holder barrel is carried within the holder body bore and has a holder head that extends therefrom for attachment to a welding electrode. The holder barrel is movable relative to the holder body between a first position, in which the holder head extends from the holder body bore a first distance, and a second position, in which the holder head extends from the holder body bore a second distance, the first distance being greater than the second distance. The coned-disc spring resides within the holder body bore, biases the holder barrel toward the first position, and is compressed by movement of the holder barrel from the first position to the second position.

A projection welding electrode holder has a holder body, a holder barrel, and a coned-disc spring. The holder body is configured for attachment to a welding machine and defines a holder body bore. The holder barrel is carried within the holder body bore and has a holder head that extends therefrom for attachment to a welding electrode. The holder barrel is movable relative to the holder body between a first position, in which the holder head extends from the holder body bore a first distance, and a second position, in which the holder head extends from the holder body bore a second distance, the first distance being greater than the second distance. The coned-disc spring resides within the holder body bore, biases the holder barrel toward the first position, and is compressed by movement of the holder barrel from the first position to the second position.

A battery-powered electronic resistance welding machine for sheet metal repair, comprising a machine unit (10), which includes a handle (12) and an activation and deactivation button (13), at least one first rod (14), which is constrained in a sliding fashion (F) to a terminal (15) of the machine unit (10), which has, at one free end, a ground electrode or tip (16) that comes into contact with at least one metal portion to create an electrical resistance circuit, at least one second rod (17), constrained in a sliding fashion (F) to the terminal (15), which has, at one free end, a welding or terminal electrode or tip (18) for the fixing of repair accessories of the metal portion. There is a rechargeable battery (11) in the machine unit (10), for example a lithium-polymer accumulator, which allows the electronic resistance welding machine to be powered without using the mains power supply.

A spot welding apparatus includes a stationary frame having a housing formed therein. An upper welding gun is mounted to a length direction of a pressing unit disposed in the housing of the stationary frame. A plurality of lower welding guns are mounted on an outside of the stationary frame and ends of the plurality of lower welding guns selectively face one end of the upper welding gun in a length direction of the lower welding guns by the plurality of lower welding guns. A plurality of actuators are mounted on the outside of the stationary frame. A plurality of link units are disposed between the actuators and the lower welding guns, connect the actuators and the lower welding guns, respectively, and rotate as the actuators are operated.

Described herein is a single-sided welding head including a first welding electrode and a second welding electrode, where the first and second welding electrodes are carried by a body of said welding head. The first welding electrode is movable relative to the body of said welding head at least along a first coordinate of motion. The second welding electrode is movable relative to the body of said welding head at least along a second coordinate of motion; where said first coordinate of motion is a coordinate of angular motion that develops about a first axis of rotation, and said second coordinate of motion is a coordinate of linear motion that develops along a first axis of translation.

Resistance spot rivet welding systems, subsystems, and methods of use thereof are provided.

A method for producing a resistance-welded member made of three or more sheets including a plated steel sheet that includes: a first energizing with a first current value while compressing the steel sheets with a first compressive force to form a nugget; a subsequent energizing of, after the first energizing, energizing with a second current value smaller than the first current value while compressing the steel sheets with a second compressive force greater than the first compressive force; and holding an electrode by maintaining the second compressive force after the subsequent energization. The second compressive force and a total sheet thickness, the first current value and the second current value, and a subsequent energization time and an electrode holding time satisfy predetermined conditions respectively.

A method for producing a resistance-welded member made of three or more sheets including a plated steel sheet that includes: a first energizing with a first current value while compressing the steel sheets with a first compressive force to form a nugget; a subsequent energizing of, after the first energizing, energizing with a second current value smaller than the first current value while compressing the steel sheets with a second compressive force greater than the first compressive force; and holding an electrode by maintaining the second compressive force after the subsequent energization. The second compressive force and a total sheet thickness, the first current value and the second current value, and a subsequent energization time and an electrode holding time satisfy predetermined conditions respectively.

An electrical connector for removably engaging a welder to a spot welding tool having a first arm in a pivoting engagement to a second arm. The connector features an electrically conductive member engaged to or forming a powered translating shaft of a welder which is surrounded by a housing. The connector engages within a passage formed in a coupling to communicate forward and rearward movement and electric current to a first arm of a spot welding tool.