Abstract: Main current passage and subsequent current passage are performed, with a cooling time of 0.01 s or more being provided between the main current passage and the subsequent current passage. Ip/I which is a ratio of a current value of the subsequent current passage to a current value of the main current passage is controlled to satisfy a predetermined relationship depending on a constant A defined by Mn content and P content of a steel sheet as a part to be welded, in relation to a welding time Tp of the subsequent current passage, a cooling time T, and the constant A.

Abstract: A first electrode coolant path is configured to cool a first welding electrode by liquid coolant flowing from a supply path through the first electrode coolant path to a return path. A second electrode coolant path is configured to cool a second welding electrode by liquid coolant flowing from the supply path through the second electrode coolant path to the return path. Three or more valves are configured to stop or reduce liquid coolant flow through the first or second electrode coolant path and configured to stop or reduce liquid coolant backflow from the return path when the first or second welding electrode is at least partially detached. At least one valve is coupled in the first or second electrode coolant path. A drawback apparatus generates a suction force to draw liquid coolant away from a gap formed when the first or second welding electrode is at least partially detached.

Abstract: A first electrode coolant path is configured to cool a first welding electrode by liquid coolant flowing from a supply path through the first electrode coolant path to a return path. A second electrode coolant path is configured to cool a second welding electrode by liquid coolant flowing from the supply path through the second electrode coolant path to the return path. Three or more valves are configured to stop or reduce liquid coolant flow through the first or second electrode coolant path and configured to stop or reduce liquid coolant backflow from the return path when the first or second welding electrode is at least partially detached. At least one valve is coupled in the first or second electrode coolant path. A drawback apparatus generates a suction force to draw liquid coolant away from a gap formed when the first or second welding electrode is at least partially detached.

Abstract: A combination component handling and connecting device connectable to a multi-axis robot for use in moving and connecting components and subassemblies includes a housing and an actuator fixedly connected to the housing. The actuator includes an actuating link movable from a first position to a second position. Connected to the actuating link is an end effector for concurrent movement with the actuating link. The component handling and connecting device includes a clamp having a first jaw and a second jaw. The second jaw is connected to the actuating link for selectively moving the second jaw toward the first jaw operative to engage a component.

Abstract: A method and system for detecting a welding gas leak is provided. One welding power supply includes a gas valve configured to control the flow of shielding gas to a welding device through a gas line. The welding power supply also includes a sensor coupled to the gas line and configured to detect a parameter of the shielding gas. The welding power supply includes control circuitry coupled to the gas valve and to the sensor, and configured to control the operation of the gas valve, and to receive device value representative of the detected parameter. The control circuitry is further configured to determine a leak test result based upon the parameter value, and to provide an operator indicator of the leak test result.

Abstract: A method of resistance spot welding a steel workpiece to an aluminum or aluminum alloy workpiece is disclosed. One step of the disclosed method involves providing a workpiece stack-up that includes a steel workpiece and an aluminum workpiece. Another step involves preheating the welding electrode that is meant to contact the aluminum or aluminum alloy workpiece. Yet another step of the disclosed method involves pressing the preheated welding electrode and another welding electrode against opposite sides of the workpiece stack-up, with the preheated welding electrode abutting the aluminum or aluminum alloy workpiece, and passing an electrical current between the two welding electrodes at a weld site to initiate and grow a molten weld pool within the aluminum or aluminum alloy workpiece.

Abstract: A welding device for welding a thicker sheet and a thinner sheet arranged congruently together. A first welding electrode having a first heat reflector or welding mirror contacts the thicker sheet with a first contact surface. A second welding electrode having a heat reflector or second welding mirror contacts the thinner sheet with a second contact surface. The first and second contact surfaces 8, 10 are at least partially congruent, and the first contact surface is larger than the second contact surface by at least a factor of two.

Abstract: A dummy weld apparatus including a dummy weld gun which allows a direct weld robot with a conventional weld gun to clamp down on the dummy weld gun to apply force and weld current for performing welding of workpieces of a first composition (e.g., aluminum). This arrangement allows the current provided by the conventional weld gun to flow through the dummy weld gun for welding the workpieces using weld tips dedicated to welding parts of the first composition, but also allows the dummy weld gun to be removed from the conventional weld gun to allow the conventional weld gun to performing welding operations on workpieces of a second composition (e.g., steel) using the original welding tips of the weld gun, avoiding material contamination of the tips.

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: An electric spot welding head for a multi-axis industrial robot that has a compact configuration, particularly in a longitudinal direction that goes from the end of the head for the attachment to the robot wrist towards the welding electrodes. This result is achieved primarily by the fact that the electrical transformer mounted on the head has its output connected to the electrode-holding arms arranged, respectively, on a front wall of the body of the transformer and on an end wall of the body of the transformer, for the connection to the electrode-holding arms of the head. The structure of the welding head is completely covered by a casing having a rear opening for connection to the robot wrist and a front opening from which the electrode arms of the welding head protrude.

Abstract: An improved cooling system for adapting to a two-component welding electrode device having a shank and cap, includes a retractable nozzle tube, a manifold, and an adjustment element for adjustably interconnecting the tube and manifold. A threaded bushing or plunger is attached to the tube and operable to adjust the distance between the interior surface of the cap and the outlet of the tube to a preferred distance. A threaded sleeve interconnects the tube and bushing for additional adjustability. The tube defines an elastically compressible bellows section, and a spacer is removably attached to the distal end of the tube for automatic adjustment of the outlet position by the cap.

Abstract: An electric actuator having an in-line rotation shaft, electric motor and encoder in which the encoder shaft, the motor shaft and the rotation shaft is concentric and integrally formed.

Abstract: A weld gun includes internal, external and structural devices that dissipate heat generated at electrode tips without requiring a continuous external source coolant. The internal devices utilize heat pipes within the electrodes to transfer heat to secondary heat removal features. A heat capacity on the weld gun contacts external heat sinks to directly conduct heat away from the weld gun after a completed weld cycle. Alternatively, the heat sink, the heat pipe and the secondary heat removal features are combined structurally on the weld gun arm by forming the arm from a plurality of plates separated by an air gap.

Abstract: The present invention relates to an improved resistance weld-based gun assembly for use in an electric welding system without a need for plant-provided air and water-cooling circulation systems. In one aspect of the invention, a resistance-based force controller measures the resistance of a secondary circuit of the weld gun, the combined resistance of the secondary circuit in parallel with the circuit formed by the workpieces and opposing electrodes when sandwiched between the electrodes, and calculates the resistance of the workpieces. The measured resistance is compared to a predetermined resistance and the sandwiching force of the electrodes incrementally adjusted until the resistance of the workpieces is acceptable. The invention also relates to a closed loop coolant system having a coolant line, a coolant contained within the coolant line, a heat exchanger, and a mechanical coolant pump. One possible pump comprises an elastic bladder dependent upon the state change of the coolant.

Abstract: In an automated welding machine, where a flow of liquid coolant is supplied to welding components on the machine from a source of coolant and then returned to the source of coolant, a safety system is provided that shuts down the flow of coolant in the event of a fault. Faults are detected by a supply sensor and a return sensor for measuring the flow rates of coolant in the supply and return lines. A microprocessor is adapted to compare the supply flow rate and return flow rate and detect differences between the two rates. The difference between the detected rates as compared to a leak threshold value, and the microprocessor is adapted to generate a valve shutoff signal in the event the detected difference in flow rates exceeds the leak threshold value. A value in the supply coolant line is responsive to the valve shutoff signal to shutoff flow of coolant in response thereto.