PURPOSE:To make titled deep drawing without generating creases on the wall part of a blank by using a pair of tapered punches in which the face opposed to the wall of a partition between a pair of parallel holes for forming and pressing the blank into above-mentioned holes for forming. CONSTITUTION:A blank 5 is held between a die 6 and a blank holder 7, and an elevating body 20 attached to a press is pushed down. With descent of punches 19, 19, the blank 5 is drawn in forming holes 8, 8 of die hole 6, and then specified deep drawing is made. while punches 19, 19 are pressed in, specified liquid pressure acts uniformly on the blank 5 as shown in the left half of the figure. Consequently, certain tension acts on the partition 10 of the blank 5 and the shoulder (e) of the punch 19 and creases do not occur in a pat 5A between the corner of inner face 21A. Material for the space is secured between the shoulders (e), (e) of a pair of punches 19, 19 at the beginning of pressing in. Thus, deep drawn tapered double sink that does not cause breakage at the corner (f) of boundary part 22 and free from generation of creases is obtained by deep drawing.
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