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:
Jul. 30, 1991
Filed:
Feb. 09, 1990
Robert T White, Spring Valley, CA (US);
Thomas J Liebig, Chula Vista, CA (US);
Jeffrey K Switzer, Poway, CA (US);
Rohr Industries, Inc., Chula Vista, CA (US);
Abstract
A method and apparatus for draw forming a metal sheet over a male form to produce a three-dimensional shape. A sheet of metal is clamped between upper and lower draw plates positioned above the male form. The upper plate has an edge conforming to the male form shape. The plates and sheet are moved downwardly over the form with the edge of the upper plate firmly pressing the sheet against the form. The clamping pressure between the draw plates allows suitable slippage as drawing proceeds to produce a drawn shape of intended thickness. The drawn shape has a configuration conforming to the outer surface of the male form and has an outer surface of improved uniformity and appearance due to the wiping action of the upper plate edge.