| 摘要 |
PURPOSE:To perform punching with good accuracy with decreased thermal influence by generating an arc between a hollow carbon electrode bar and a metallic plate, blowing high-velocity air to the arc generating part and removing the molten metal toward the rear side through the hollow part of the electrode. CONSTITUTION:A hollow carbon electrode bar 2 applied with a metallic coating on the outside circumference is mounted to a holding part 4 and is erected approximately perpendicularly to a metallic plate 1 to be worked. A high voltage is impressed between the bar 2 and the plate 1 to generate an arc between both and at the same time high-velocity air is blown to the arc generating part through each hole 5 in the part 4 to carry out the molten metal through the hollow part of the bar 2 toward the direction Z, thus punching a hole 6 in the plate 1. The thermal influence to the metallic plate to be worked is thus decreased and the metallic plate is safely punched with the hole with good accuracy. |
