DIE FOR DRAWING

摘要

PROBLEM TO BE SOLVED: To provide a die for drawing capable of shaping a trihedral corner at an angle closest to orthogonal to high sidewall portions.SOLUTION: A die (1) for drawing includes a punch (10) for inserting a material plate so as to form an inner shape of a polygonal container, a die (20) having a polygonal hole (21) which allows the material plate inserted by the punch (10) to enter, a blank holder (30) having a polygonal hole (31) for the insertion of the punch (10) and holding the material plate at the circumference of the hole (21) of the die (20). Linear portions (23) and (24) of the hole (21) of the die (20) include a portion having an enlarged radius of curvature where the radius of curvature of the shoulder portion between a clamping surface (27) and the circumferential wall (21a) of the hole (21) is larger than the radius of curvature of shoulder portions at the corners (22).