Invention Application
- Patent Title: METHOD FOR PRODUCING BLANK, METHOD FOR PRODUCING PRESS-FORMED PART, METHOD FOR JUDGING SHAPE, PROGRAM FOR JUDGING SHAPE, APPARATUS FOR PRODUCING BLANK, AND BLANK
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Application No.: US17626321Application Date: 2020-07-10
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Publication No.: US20220241838A1Publication Date: 2022-08-04
- Inventor: Jun NITTA , Takashi YASUTOMI , Ryo TABATA
- Applicant: NIPPON STEEL CORPORATION
- Applicant Address: JP Tokyo
- Assignee: NIPPON STEEL CORPORATION
- Current Assignee: NIPPON STEEL CORPORATION
- Current Assignee Address: JP Tokyo
- Priority: JP2019-130421 20190712
- International Application: PCT/JP2020/027152 WO 20200710
- Main IPC: B21D28/34
- IPC: B21D28/34 ; B21D28/14 ; B23D15/08

Abstract:
The present invention has as its technical problem to provide a punching method able to stably secure a stretch-flangeability equal to or greater than the case of using a punch having a flat blade at its bottom surface. The punching method of the present invention is a method of punching a metal sheet using a punching and shearing device provided with a punch having an upper blade having a horizontal part with respect to the cutting line in part and having parts other than the horizontal part comprised of inclined parts and a die having a lower blade wherein the upper blade used for the punching process has a shape where the inclined parts first contact the metal sheet at the time of a punching process.
Information query