FIELD: metal processing.
SUBSTANCE: invention relates to wasteless cutting of workpieces from sheet material. After feed reel per step per every press stroke by means of first and second knives installed on press die first workpiece is cut with first knife at first curve and second knife along second curve from sides of roll. Part of first and second curves are plotted, first, as symmetric and mirror reflection of first and second curves relative to vertical axes passing through centres of those curves, and then as symmetric and mirror reflection relative to reel horizontal symmetry axis, simultaneously using die second knife second workpiece is cut from roll.
EFFECT: for all versions of rectangular workpiece cutting two shaped blanks are cut without wastes with overlap of previous workpiece inside contour of next workpiece, due to which decrease of roll feed pitch is performed, high accuracy of cut workpieces and die durability.
4 cl, 4 dwg
