A welding gun includes a proximity restricting mechanism that is provided between a shaft and a cover member in a manner to surround the shaft and to be displaceable relative to the shaft in an axial direction in accordance with expansion and contraction of the cover member, and that restricts the cover member from approaching too closely the shaft.

A welding gun includes a proximity restricting mechanism that is provided between a shaft and a cover member in a manner to surround the shaft and to be displaceable relative to the shaft in an axial direction in accordance with expansion and contraction of the cover member, and that restricts the cover member from approaching too closely the shaft.

A spot welding method for welding a first panel and a second panel by applying a current between a pair of electrodes in pairs in a state in which the first panel and the second panel overlap one another and are held by the electrodes includes: forming a protrusion on a surface facing the second panel, at a welding-target part of the first panel; forming a recess on a surface facing the protrusion, at a welding-target part of the second panel, such that the recess has a depth that allows a top of the protrusion to come into contact with a bottom of the recess; and holding the welding-target part of the first panel and the welding-target part of the second panel between the electrodes, in a state in which the protrusion is inserted in the recess and applying the current between the electrodes.

A spot welding method of spot welding a workpiece including a first panel, a second panel, a third panel, and a fourth panel stacked in sequence includes: conducting indirect spot welding for the first panel and the second panel to form a first weld zone where the first panel is joined to the second panel; conducting indirect spot welding for the third panel and the fourth panel to form a second weld zone where the third panel is joined to the fourth panel; and, after forming the first weld zone and the second weld zone, conducting direct spot welding for the workpiece to form a third weld zone where the second panel is joined to the third panel.

A spot welding method of spot welding a workpiece including a first panel, a second panel, a third panel, and a fourth panel stacked in sequence includes: conducting indirect spot welding for the first panel and the second panel to form a first weld zone where the first panel is joined to the second panel; conducting indirect spot welding for the third panel and the fourth panel to form a second weld zone where the third panel is joined to the fourth panel; and, after forming the first weld zone and the second weld zone, conducting direct spot welding for the workpiece to form a third weld zone where the second panel is joined to the third panel.

A projection portion is formed on a distal end surface of a supply rod with which a surface of a flange is brought into close contact. A circular-arc receiving surface is formed at a boundary portion between the distal end surface and the projection portion, and is configured to fit a flange outer peripheral portion. One side of the circular-arc receiving surface is continuous with the distal end surface, and another side of the circular-arc receiving surface is continuous with an inclined guide surface. The close contact of the flange with the distal end surface is achieved with a magnet of an advancing/retreating type provided in the supply rod.

A welding gun and a welding method with which it is possible to reduce, the wait time for loading a component and to decrease tact time. The welding gun is a welding gun for resistance-welding components to a workpiece successively, and comprises a first holding portion and a second holding portion for holding a component. The first holding portion and the second holding portion are each switchable to an abutment-enabling position for causing a component to abut against a workpiece, or to a loading-enabling position for loading the component. The first holding portion and the second holding portion are switchable such that when the first holding portion is in the abutment-enabling position, the second holding portion is in the loading-enabling position, and when the second holding portion is in the abutment-enabling position, the first holding portion is in the loading-enabling position.

A welding gun and a welding method with which it is possible to reduce, the wait time for loading a component and to decrease tact time. The welding gun is a welding gun for resistance-welding components to a workpiece successively, and comprises a first holding portion and a second holding portion for holding a component. The first holding portion and the second holding portion are each switchable to an abutment-enabling position for causing a component to abut against a workpiece, or to a loading-enabling position for loading the component. The first holding portion and the second holding portion are switchable such that when the first holding portion is in the abutment-enabling position, the second holding portion is in the loading-enabling position, and when the second holding portion is in the abutment-enabling position, the first holding portion is in the loading-enabling position.

A projection portion is formed on a distal end surface of a supply rod with which a surface of a flange is to be brought into close contact. A circular-arc receiving surface fitting an outer peripheral portion is formed at a boundary portion between the distal end surface and the projection portion. One side of the circular-arc receiving surface is continuous with the distal end surface, and another side of the circular-arc receiving surface is continuous with a regulation inner surface formed on the projection portion in a state of being opposed to the distal end surface. With this, a receiving groove is formed, and a control gap is defined between the regulation inner surface and the flange. The close contact of the surface with the distal end surface is achieved with a magnet of an advancing/retreating type provided in the supply rod.

The present disclosure provides a method of resistance spot welding that can inhibit Liquid Metal Embrittlement-induced cracking in zinc-coated steel plates irrespective of the degrees of tensile strength. One aspect of the present disclosure provides a method of resistance spot welding. The method comprises 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 welding while compressing a high-tensile steel plate among the two or more steel plates in a direction intersecting a direction of a thickness of the high-tensile steel plate. The high-tensile steel plate has a tensile strength higher than a tensile strength of another steel plate among the two or more steel plates.