| 摘要 |
PROBLEM TO BE SOLVED: To provide a spot welding method capable of expanding a proper current range of spot welding, by preventing the occurrence of dust easily and reliably, without the need for complex control.SOLUTION: A spot welding apparatus includes: a pair of electrodes 1 coming into abutment with a stacked part of two or more stacked metal plates from both sides thereof for causing an electric current to flow into the stacked part; and a pressure member 2 for pressurizing the stacked part in areas [a1+a2+a3] of 20% or more of the whole periphery of the tip outer circumference of the electrodes 1 in which the distance from the tip outer circumference of the electrodes is within 5 mm, and also having non-pressurized area [b1,b2,b3] of the whole periphery of the tip outer circumference of the electrodes 1, the area becoming 30% or less (including 0%) of the whole periphery of the tip outer circumference of the electrodes, successively. By using the spot welding apparatus, the stacked part is sandwiched by the pair of electrodes 1 with a load of 100 N or more, and also the peripheries of the electrodes 1 are pressurized by the pressure member 2 with a load of 5-1000% of the load by the pair of electrodes 1, thereby joining the stacked part by carrying a welding current thereto from the electrodes 1. |
