RESISTANCE-WELDING DEVICE

To satisfactorily generate nuggets while suppressing occurrence of spatter and burrs in a resistance-welding device for joining a plurality of laminated metal plates.SOLUTION: A resistance-welding device joins a plurality of metal plates by use of a rivet 30. The device comprises an upper electrode 10 which presses the rivet 30 in a lamination direction with respect to the plurality of metal plates, and a lower electrode which presses the plurality of metal plates to the upper electrode 10 side. The device uses, as the rivet 30, a product having: a shade part 31 of which a top face 31a contacts an apical surface 10a of the upper electrode 10; a shank 33 which extends downward from a center of the shade part 31; and an outer peripheral wall part 35 which extends from a peripheral edge part of the shade part 31 in the same direction as the shank 33, and forms a groove 37 between itself and the shank 33. A diameter D1 of a contact surface between the upper electrode 10 and the shade part 31 of the rivet 30 when starting electric conduction is so set as to be larger than an outer diameter D2 on the shade part 31 side in the shank 33, and to be smaller than an inner diameter D3 of the outer peripheral wall part 35.SELECTED DRAWING: Figure 2 【課題】積層された複数の金属板を接合する抵抗溶接装置において、スパッタやバリの発生を抑えつつ、ナゲットを良好に生成させる。【解決手段】リベット３０を用いて複数の金属板を接合する抵抗溶接装置である。複数の金属板に対して、リベット３０を積層方向に押圧する上部電極１０と、複数の金属板を上部電極１０側へ押圧する下部電極と、を備えている。リベット３０として、上部電極１０の先端面１０ａと上面３１ａが接触する笠部３１と、笠部３１の中央から下方へ延びる軸部３３と、笠部３１の周縁部から軸部３３と同じ向きに延びて、軸部３３との間に溝３７を形成する外周壁部３５と、を有するものを用いる。通電開始時における上部電極１０とリベット３０の笠部３１との接触面の径Ｄ１が、軸部３３における笠部３１側の外径Ｄ２よりも大きく、且つ、外周壁部３５の内径Ｄ３よりも小さく設定されている。【選択図】図２