Patent ID: 8156780
Filing Date: 2012-04-17
Classification: B21D,B23D,Y10T

Abstract:
1. A method of cutting high-tensile workpieces, wherein the workpiece is subjected to a bending stress prior and during a shearing process, wherein the bending stress causes a substantial component of a tensile force transverse to a desired cutting contour; wherein the workpiece is loaded with a bending moment, which causes a tensile stress at the cutting contour, and wherein the bending moment is caused by means of a projection provided at a cutting knife; wherein the projection is provided at a distance from a cutting edge of the cutting knife, and, when performing the shearing process, the projection hits the workpiece before the cutting edge; and wherein a distance a between the cutting edge and the projection and a height h of the projection have a ratio a/h determined by a thickness d of the workpiece and a constant k, as follows: wherein k has a selected value between 0.8 and 6.