Abstract: An equalizing mechanism of a welding apparatus connects an apparatus body and a fixed bracket, and includes a fixed member on the fixed bracket, and a pressure shaft on an apparatus body close to a bottom face of the fixed member. A cutout is at a position facing the fixed member A movable member on the apparatus body accommodates the fixed member. A restrictive member located by side faces of the fixed member and the movable member restricts relative movement thereof to a direction parallel to the pressure shaft. A driven lever is supported by a front portion of the fixed member to abut on an inner front face of the movable member at one end and abut on the pressure shaft at an other end. A spring between a back portion of the fixed member and an inner back face of the movable member presses the two members to move away from each other.

Abstract: A weld gun for performing a welding operation on a workpiece includes a pair of opposing arms, at least one arm movable relative to the opposing arm to apply pressure to the workpiece during a welding operation. A pair of identical or mirror image side plates support components of the weld gun to establish critical dimensions of the components relative to one another, while preventing tolerance buildup of critical dimensions at critical points. A guide block is connected to one of the opposing arms. The guide block has a non-circular aperture formed therein. An electrode adapter has a non-cylindrical rod portion slidably received in the non-circular aperture formed in the guide block for preventing rotation of the electrode adapter. A hose fitting is attachable directly to a rear end of the electrode adapter for communicating with an inlet water port and an outlet water port formed in the electrode adapter for providing a routing of coolant directly through the electrode adapter only.

Abstract: A resistance welding head carries out resistance welding while clamping spots are being welded by a pair of electrodes. The head is floated in a direction Y perpendicular to a direction X of juxtaposing the spots being welded. The pair of electrodes clamp the spots being welded while centering by acting a reaction force exerted when the electrodes clamp the spots to the resistance welding head. Then, resistance welding starts.

Abstract: In a resistance welding machine, an arm including one electrode tip, a drive unit including a linear guide for driving another electrode tip corresponding to the one electrode tip, and a welding unit including a welding transformer for passing a secondary current through a gun bracket for supporting the present resistance welding machine on a robot and/or the present resistance welding machine, can be mounted and removed individually as a unit with a common base or a rail main body including the linear guide as the reference thereof.

Abstract: A method and apparatus for resistive welding using an electrode holder having an elongated cylinder. The cylinder has a closed end and an open end. The cylinder contains a moveable piston. The piston includes a compression surface and an end adapted to retain a welding electrode. A compressible biasing member is positioned within the cylinder and is compressed between the closed end and the compression surface. An electrode is attached to the holder. The holder is preferably used as a lower electrode holder opposite a moveable upper cylinder. A work piece is placed between the upper cylinder and lower holder. The upper cylinder is extended and applies a force to the holder through the electrodes and work piece. The force causes the biasing member to compress within the lower elongated cylinder and apply a counter force against the lower surface electrode.

Abstract: A plate-shaped jig (9) is fixed between a fixed-side electrode (5) and a moving-side electrode (6). The end of an arm is set to move by an external force in the direction the moving-side electrode (6) moves, and then the moving-side electrode (6) is moved toward the jig (9) and pressed against the jig (9) by such a force that the end of the arm is pushed up by a counterforce, the position of a robot in a tool coordinates system and the position of a gun-axis servomotor (7) are acquired as reference positions when the jig (9) is held between the moving-side electrode (6) and the fixed-side electrode (5) to release the holding of the fixed jig (9) with pressure. Thereafter, similarly , the position of the robot and the position of the gun-axis servomotor (7) are acquired to calculate the wear amount of the fixed-side electrode (5) and the moving-side electrode (6) from the respective differences from the reference positions.