| 摘要 |
PURPOSE:To improve joining strength of spot welding of a laminated steel plate by vibrating pressing electrodes by ultrasonic waves at the time of preheating to remove a resin layer of a welding point and pressing and electrifying said welding point by the electrodes to perform welding thereon. CONSTITUTION:The laminated steel plate 1 formed by laminating the resin layer 1a between a couple of steel plates 1b and 1c and an ordinary steel plate 2 are held between the upper electrode 3a and the lower electrode 3b. These are pressed and electrified by both electrodes 3a and 3b. At a first stage, at the time of preheating, the upper electrode 3a is vibrated by an ultrasonic oscillator 6 and a vibrator 7 and the resin layer of the spot welding point is softened and removed. At a second stage, the welding point where the resin layer is removed is pressed and electrified by both electrodes 3a and 3b and welded and joined together. By this method, the joining strength of spot welding of the laminated steel plate can be improved. |
