Provided is a resistance spot welding method wherein main current passage includes two or more electrode force application steps including a first electrode force application step and a second electrode force application step following the first electrode force application step, an electrode force F.sub.1 in the first electrode force application step and an electrode force F.sub.2 in the second electrode force application step in the main current passage satisfy a relationship F.sub.1>F.sub.2, and an electrode force switching point T.sub.f from the first electrode force application step to the second electrode force application step in the main current passage is set to satisfy predetermined relational formulas.

An opposing electrode determination method includes a step of inserting a pair of opposing electrodes into corresponding receiving portions, respectively, by holding, between the pair of opposing electrodes, a held member formed with the receiving portions on both sides; a step of measuring the inter-electrode distance between the pair of opposing electrodes; and a step of determining, based on the inter-electrode distance, whether a combination of the pair of opposing electrodes is correct or incorrect. The receiving portions are configured to have different insertion allowances for the opposing electrodes, respectively, according to the tip shape of each of the pair of opposing electrodes.

A cap tip assembly for spot welding is disclosed. The cap tip assembly for spot welding is configured to spot-weld a first base material in which a flange is formed and a second base material overlapping the flange in a vertical direction. The cap tip assembly for spot welding includes a tip body provided in a shape of a rectangular block in which a round-shaped welding section is formed on a front side of a top surface, and a collet member coupled to the tip body to guide a conductive tape to the welding section.

The present invention includes a reference parallel line creation step of creating a pair of parallel lines that are respectively in contact with outer edges of a workpiece cross-section without traversing the workpiece cross-section and that are located on an extension plane of the workpiece cross-section, a first determination step of comparing a width between the pair of parallel lines that have been created in the reference parallel line creation step with a maximum separation threshold of the welding electrodes, and determining whether the maximum separation threshold is larger than the width between the parallel lines, and a pull-out direction determination step of determining a direction of the parallel lines as a pull-out direction, in a case where the maximum separation threshold is larger than the width between the parallel lines in the first determination step.

The present invention relates to an electrode assembly, wherein a plurality of electrodes is stacked in the state in which a separator is interposed between the electrodes, electrode tabs protruding from the electrodes are coupled to an electrode lead in a state of forming an electrode tab bundle, the electrode lead includes a first electrode lead coupled to the electrode tabs and a second electrode lead coupled to the first electrode lead, and an electrode lead coupling portion configured to allow the first electrode lead and the second electrode lead coupled to be coupled to each other includes an adhesion portion and a spot welding portion.

The air blow nozzle includes a nozzle body configured to be connected to an air compressor one end thereof and includes an air discharge portion another end thereof, the air discharge portion is capable of discharging compressed air supplied from the air compressor. The air discharge portion is configured to be movable to a position that does not correspond to an upper communication hole as the nozzle body is slid to one side. The nozzle body includes a nut configured to position the air discharge portion in a predetermined position near a rotary holder as the nozzle body is slid to another side.

An electrical apparatus includes first and second welded members that are welded together. The first welded member has a first metal part and a first resin part covering part of the first metal part. The second welded member has a second metal part and a second resin part covering part of the second metal part. The first metal part has a first standing terminal portion exposed from the first resin part and standing in a standing direction. The second metal part has a second standing terminal portion exposed from the second resin part and standing in the standing direction. The first and second standing terminal portions are welded to each other so that a weld is formed therebetween. The first and second resin parts partially overlap each other in the standing direction. The weld is within a projection region of the first and second resin parts in the standing direction.

Art for spot welding able to suppress penetration of hydrogen, one of the factors behind delayed fracture, at the time of spot welding, that is, a spot welding method in which at one or both of the surfaces of the steel sheets becoming the facing surfaces of the overlaid steel sheets, a location where the steel sheets contact each other to form a contact part at the time of initial squeezing of the spot welding is worked in advance to form a plurality of lines running through the contact part and connected to the outside of the contact part and the spot welding is performed at the location of the contact part and also a steel sheet in which the plurality of lines are formed in advance at the location becoming a contact part when steel sheets contact each other at the time of initial squeezing in the spot welding.

A welding quality inspection apparatus for inspecting the welding quality of a plurality of welding parts formed on the material through the upper electrode and the lower electrode of the welding gun includes a position detection unit for detecting a position of the upper electrode, a control unit generating a position table based on a signal detected by the position detection unit during a total welding time of welding the plurality of welding parts of the material, generating first position data for a first welding time and second position data for a second welding time of a spot welding time of each of the welding parts based on the position table, checking whether the welding parts are defective by using the first position data, the second position data, and reference data, and generating result data based on whether the welding parts are detective, and an output unit for outputting the result data.

A welding quality detection system and a welding quality detection method are provided. A detection device applies a force to at least one weld point of a first welded object or a second welded object that are welded together. A displacement detector detects a displacement signal that varies with the force or time between the first welded object and the second welded object based on the force. A detection module receives or records the displacement signal and determines whether a gap exists between the first welded object and the second welded object based on a slope of the displacement signal, so as to detect the welding quality of the weld point quickly and precisely.