Abstract: A welding gun apparatus having a gun bracket, a pair of arms pivotally mounted on the bracket, a transformer mounted on the bracket, and a pressure applying mechanism on the bracket for opening and closing the gun arms; characterized in that the gun bracket comprises a frame which extends longitudinally from a front pivot portion for pivotally supporting the gun arms to a rear portion, the transformer being positioned in and fixed to the frame between the front pivot portion and the rear portion.

Abstract: The present invention is directed to a gun arm for a resistance welding gun. The gun arm comprises a main body, an electrode holder mounted on the front portion of the main body and a support member fixed to the rear portion of the main body. The main body comprises a conductor member having a water passage on at least one side thereof and a plate member fixed to at least one side of the conductor member and in contact with the water passage. In one embodiment of the present invention, the water passage comprises at least one groove formed in the conductor member with the groove being covered by the plate member. In an alternative embodiment, the water passage comprises at least one pipe which is positioned between the plate members which comprise the at least one plate member.

Abstract: The present invention is directed to a gun arm apparatus for a resistance welding gun. The gun arm apparatus comprises a main body having a U-shaped cross-section with an opening formed between the legs of the U. The main body is formed from a relatively thin metal and the main body includes an electrode holder at one end thereof, a support at the other end thereof and an electrical terminal at the other end thereof. An electrical conductor member is fixedly mounted in the opening between the legs of the U-shaped main body. The electrical conductor member is formed from a relatively thick plate member. The conductor connects the electrode holder to the electrical terminal. A cooling water passage is positioned in contact with the conductor for carrying cooling water to cool the electrical conductor member. In one embodiment, the cooling water passage comprises at least one pipe fixedly attached to the conductor and in another embodiment, the cooling passage comprises grooves formed in the conductor.

Abstract: A multi-spot welding arrangement in which a jig table on the front surface of a machine frame has a plurality of welding guns located along the shape or contour of the workpiece to be processed or worked. An electric supply has a plurality of units which are connected to the welding guns through respective electric supply cables. A pressure applying mechanism has a plurality of operation cylinders which are connected to the welding guns through respective flexible wires, and is located on the rear side and the upper side of the machine frame. The machine frame, moreover, has a front frame and a rear frame which are coupled together in a detachable manner. The jig table and the pressure applying mechanism are located on the front frame, and the electric supply is provided on the rear frame.