Patent ID: 11890661
Assignee: HEFEI UNIVERSITY OF TECHNOLOGY
Field: Machine tools (Mechanical engineering)
Classification: CPC B | IPC B

Claim 5:
6. The method of claim 5, wherein the contour characteristic comprises at least one of a straight line and a curve, and dividing the blank holder of the stamping device into s areas in the circumferential direction based on the contour characteristic of the workpiece to be stamped comprises:
in a case that a straight line La is connected to a curve Ca, determining an area formed by the straight line La, a first vertical line of the straight line La passing through one end point of the straight line La, a second vertical line of the straight line La passing through a connection point of the straight line La and the curve Ca, and a line segment between points where the first vertical line and the second vertical line intersect with an outer edge of the blank holder as a first area; determining an area formed by the curve Ca, a third vertical line perpendicular to a tangent line passing through one end of the curve Ca, the second vertical line, a curve between the points where the second vertical line and the third vertical line intersect with the outer edge of the blank holder as a second area, wherein a curvature q at the connection point of the straight line La and the curve Ca is 0;
in a case that a curve Cb is connected to a curve Cc and curvatures of the curve Cb and the curve Cc satisfy (qmax−qmin)/qmax≥0.05, determining an area formed by the curve Cb, a fourth vertical line perpendicular to a tangent line passing through one end point of the curve Cb, a fifth vertical line perpendicular to a tangent line passing through a connection point of the curve Cb and the curve Cc, and a curve between points where the fourth vertical line and the fifth vertical line intersect with the outer edge of the blank holder as a third area; and determining an area formed by the curve Cc, a sixth vertical line perpendicular to a tangent line passing through one end of the curve Cc, the fifth vertical line, and the curve between points where the fifth vertical line and the sixth vertical line intersect with the outer edge of the blank holder as a fourth area, where qmax represents a maximum value of curvatures of points on the curve Cb or the curve Cc, qmin represents a minimum value of the curvatures of points on the curve Cb or the curve Cc, and a curvature change rate at the connection point of the curve Cb and the curve Cc is the largest; and
in a case that the curve Cb is connected to the curve Cc and the curvature of the curve Cb and the curve Cc fails to satisfy (qmax−qmin)/qmax≥0.05, determining an area formed by the curve Cb, the curve Cc, the fourth vertical line, the sixth vertical line, and a curve between points where the fourth vertical line and the sixth vertical line intersect with the outer edge of the blank holder as a fifth area.