The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 20, 2019
Filed:
Nov. 11, 2014
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Yuzo Takahashi, Tokyo, JP;
Osamu Kawano, Tokyo, JP;
Tatsuo Yokoi, Tokyo, JP;
Junji Haji, Tokyo, JP;
Satoshi Horioka, Tokyo, JP;
NIPPON STEEL CORPORATION, Tokyo, JP;
Abstract
Tooling used in a punching process which uses a die and projecting punch to form a worked material of steel sheet into a predetermined outer shape, in which tooling for punching, a radius of curvature Rd of a die cutting edge is from 0.03 mm to 0.2 mm and an angle (α) formed by a tangent drawn from a punch cutting edge to a projection shoulder and a direction perpendicular to a direction of movement of the punch is from 12° to 72°, and a punching method and shaping method using the same, are provided. Further, when making the die cutting edge (shoulder R part) a two-stage R of radii of curvature Rand Rand making a slant of a line passing through the centers of Rand Rβ, by making 0.03 mm≤R≤0.2 mm, 1≤R/R≤5, 0≤R(1−sin β1)≤0.3t, and 30°≤β≤90°, punching hole expandability can be improved.