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:
Mar. 07, 1978
Filed:
Sep. 30, 1975
Dennis C Stewart, West Palm Beach, FL (US);
United Technologies Corporation, Hartford, CT (US);
Abstract
A method of improving the formability of sheet metal wherein the sheet metal is formed by die pins contacting spaced parts of the sheet with the properties of the sheet material itself determining the actual condition of curvature between the spaced parts contacted by the die pins. The sheet metal is perforated at the spaced part of the sheet contacting each die pin so that as each die pin is pressed into the sheet, each perforation expands and additional sheet material is supplied to the shoulder of the pin. Tops of the die pins can be modified with a boss to locate the perforations in the sheet metal and position it in respect to the die pins. Modified die pin tops can be formed with pointed inserts so that solid sheet metal can be used with the inserts piercing the sheet and the die pins then forming it. The sheet metal can also be partially formed and then perforated before the final forming.