| 摘要 |
PURPOSE:To extend an electrode to a long life without deteriorating a welding quality by forming a projecting part for constituting a passage in which a current density of a welding current is constant, on the surface of the tip side of an electrode for spot welding. CONSTITUTION:Dome-shaped recessed parts 20, 22 which are fitted to the surface of the tip side of spot welding use electrodes 16, 18 are formed on an upper face 12 and a lower face 14 of a jig 10 for constituting a cube. In the center parts of the recessed parts 20, 22, annular grooves 24, 26 are formed, respectively. The surface of the tip side of the electrodes 16, 18 is made to abut on the inside of the recessed parts 20, 22 of the jig 10, and the electrodes 16, 18 are pressed against the jig 10 by a pressing force of the time of welding or the stronger pressing force than said force. When the electrodes 16, 18 pressed against the jig 10, projecting parts 28, 30 for constituting a passage in which a current density of a welding current is constant are formed on the surface of the tip side of the electrodes 16, 18 by a forging pressure action. |
