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:
Dec. 04, 1979
Filed:
May. 19, 1978
Applicant:
Inventors:
John E Cromwell, Baltimore, MD (US);
Nicholas Herbert, Baltimore, MD (US);
Glenn F Hyde, Timonium, MD (US);
Assignee:
Koppers Company, Inc., Pittsburgh, PA (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
B23P / ;
U.S. Cl.
CPC ...
2915663 ; 277224 ; 2772 / ; 204 25 ;
Abstract
A method of making piston rings comprising forming annular stepped grooves in the outer periphery of a plurality of piston ring blanks, stacking the blanks on a rotatable arbor, electro-depositing a layer of chromium in the grooves and on the outer surfacs of the ring blanks, and removing an outer portion of the chromium layer and the outer bearing faces of the ring blanks to form a plurality of piston rings having a continually axially convex surface on the face of the ring formed by the deposited chromium and bearing faces of the ring.