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. 22, 1980
Filed:
Dec. 12, 1977
Applicant:
Inventor:
Johannes A De Deugd, Eindhoven, NL;
Assignee:
U.S. Philips Corporation, New York, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B21D / ;
U.S. Cl.
CPC ...
72358 ; 72370 ;
Abstract
Method and apparatus for extruding burr holes in a metal sheet, in which a punch with a conical end portion and adjoining cylindrical portion of a diameter greater than the inner burr diameter is passed through the burr. The conical end portion has a half apex angle between 10.degree. and 20.degree., and the axial length of the cylindrical portion and the coefficient of friction between the cylindrical portion and the burr wall are selected according to a specified relationship.