| 摘要 |
PURPOSE:To process a scrap by one process, to make a cutting die small in size, and to simplify the process by forming a slit by a tongue piece-shaped cut-rise, in an area which becomes a scrap, in a sheet metal base material, and working a base material to a prescribed shape. CONSTITUTION:A cut-rise working of a tongue piece part 7 of a long circular shape is performed as a pre-working to the center part of an area S which becomes a scrap 4, in a sheet metal base material W of a long side supplied to a cutting die, and a C-shaped slit 7a of non-punching type is formed. Subsequently, the base material W is fed in order by one pitch P in the direction as indicated with an arrow A, and as the next process, a long hole 2 is punched by a cutting line crossing said slit 7a by a prescribed punch. The scrap 4 generated as a result is divided and shortened to short pieces 4a, 4b in the slit 7a and dropped. Thereafter, the base material W is fed in order by additional one pitch P, cut by a cutting line 3 passing through the center of the long hole 2 by a blanking edge, and a punched material B of a prescribed shape is obtained. |
