A radially slotted welding electrode is disclosed that may be used in conjunction with a companion second welding electrode to conduct resistance spot welding on a workpiece stack-up assembly that includes a steel workpiece and an overlapping adjacent aluminum workpiece, especially when an intermediate organic material layer is disposed between the workpiece faying surfaces of the steel and aluminum workpieces. The radially slotted welding electrode includes a weld face that has a central upstanding plateau and a convex dome portion that surrounds the central upstanding plateau and which includes a plurality of circumferentially spaced trapezoidal weld face sections that include transverse upstanding arcuate ridges. Together, the central upstanding plateau and the trapezoidal weld face sections of the convex dome portion define an annular channel that surrounds the central plateau and a plurality of radial slots that communicate with and extend outwards from the central channel.

A guide hole is constituted of a large-diameter hole, a medium-diameter hole, and a small-diameter hole. A sliding part fitted in the guide hole is formed of a synthetic resin material. A large-diameter portion of the sliding part is fitted in the large-diameter hole in a slidable state, and a medium-diameter portion is fitted in the medium-diameter hole in a slidable state. A movable end surface of the sliding part is in close contact with a stationary inner end surface of the guide hole. By configuring a width dimension of the movable end surface to be less than half of a thickness dimension of the large-diameter portion, a pressurizing force of the movable end surface is increased and a minute metal piece is pushed from the movable end surface into a base material of the sliding part, and a thickness dimension of the medium-diameter portion is set large.

An apparatus for cooling-water extraction for a robot installation plate is characterized by an adjustable extraction volume. The extraction volume is achieved by a sufficiently large extraction cylinder which has a maximum extraction volume, wherein the extraction volume is adjusted by a mechanical stroke limit of a piston located in the extraction cylinder. In at least one embodiment, the mechanical stroke limit is realized by an adjustment screw that is on or in the extraction cylinder. The adjustment screw forms a stop that provides an end position limit or stroke limit of the piston.

A method for joining two dissimilar metal plates having different volume resistivity with enhanced joint strength. The method includes overlaying a first metal plate made of first metal and a second metal plate made of second metal with higher volume resistivity and higher melting point in comparison with the first metal, bringing a pair of electrodes into contact with the surface of a portion of the second metal plate overlapping the first metal plate, supplying current between the electrodes so as to resistance-heat the second metal present in a current-flowing region to a temperature lower than the melting point of the second metal and higher than the melting point of the first metal, thereby partially melting the first metal plate with the heat so that an intermetallic compound is generated between the first and second metal plates, and thus joining the first and second metal plates via the intermetallic compound.

This spot welding method for an aluminum material comprises: a processing step in which, in a plan view, a circular emboss expanded in a direction of superposition on a second aluminum plate side is formed at a position-to-be-welded of a first aluminum plate; an arrangement step in which positions-to-be-welded are superimposed while the expansion side of the emboss faces the second aluminum plate, and the positions-to-be-welded are arranged between a pair of electrodes; a pressing step in which the superimposed aluminum plates are pinched between the electrodes, and a central side excluding a peripheral edge of the emboss is pressed; and an electrification step of performing pressing and electrification. An electrode having a tip diameter larger than the diameter of a root part of the expansion part of the emboss is used.

A resistance welding device is configured for use in combination with a resistance welder having a translating welding electrode. A first arm of the welding device is in a translating rotational engagement with a second arm thereof. The first arm of the device is engageable to a translating electrode from the resistance welder. Translation of the welding electrode of the resistance welder moves first and second electrodes to contact metal therebetween and spot weld the metal.

A bonding probe is used for bonding a cover sheet to a core to form or repair a dual wall structure. The bonding probe includes a body, an attachment end at a distal end of the body, a head at an opposite end of the body, a tip extending from the head, and a cooling passageway. The attachment end couples the body to a resistance welder. The tip extends to form a proximate end of the body. The tip includes a contacting area having a predetermined three dimensional contoured surface. The contacting area aligns with a predetermined area of a three dimensional outer surface of a cover sheet of a dual walled structure. The cooling passageway provides a passageway for a flow of cooling fluid. The cooling passageway extends through the head, and into the tip.

The present disclose provides a method of resistance spot welding that can inhibit Liquid Metal Embrittlement-induced cracking in zinc-coated steel plates irrespective of the plate thicknesses. One aspect of the present disclosure provides a method of resistance spot welding that includes welding a workpiece with a resistance spot welding apparatus. The workpiece includes two or more steel plates in an overlapping state. The two or more steel plates include at least one steel plate coated with zinc. The welding includes causing a cooling rate of a high-tensile steel plate among the two or more steel plates to be higher than a cooling rate of an other steel plate among the two or more steel plates. The high-tensile steel plate has a tensile strength higher than a tensile strength of the other steel plate.

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.

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.