| 摘要 |
PROBLEM TO BE SOLVED: To provide a press punching method of a metal sheet and a press die in which punching of high quality can be performed in a work without using any complicated handler cam by allowing the axial deviation of a punch from a punching die, the cost for the press die can be reduced, and the manufacturing period of the press die can be shortened. SOLUTION: The shaft size of the punch 1 held by an upper die 5 with respect to the hole size of the punching die 3 embedded in a lower die 2 is set to be smaller than the dimension used for shearing, a sharp projection 1a capable of piercing 1-N works 4 is installed on a tip thereof, and a pierced hole is made in the works 4 by the sharp projection 1a by pressing the punch 1 with a rounded portion on an outer circumferential corner part 1b. In addition, the works 4 are broken from an outer circumferential part 3a of the hole by pressing the punch to make a hole of the same shape as that of the punching die 3.
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