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:
Apr. 25, 1978
Filed:
Apr. 01, 1976
Harold E McCormick, Ballwin, MO (US);
Herbert F Prasse, Town and Country, MO (US);
William F Ott, St. Louis, MO (US);
Donald J Mayhew, St. Louis, MO (US);
Ramsey Corporation, St. Louis, MO (US);
Abstract
A rolled steel oil control piston ring for internal combustion engines is of generally U-shaped cross section with a pair of opposed rigid sidewalls projecting inwardly of the ring from a central peripheral wall thereof. A pair of flat-faced solid scraper rims formed by closed pleats rolled from the peripheral wall extend outwardly of the ring. The ring is made by rolling flat strip steel stock through a series of profiled rollers by guiding the edges of the stock without deforming the same, while taking up dimensional variations of the stock by displacement of the central portion of the strip. Pleats are formed in the central portion by the profiled rollers and the pleats are closed on themselves to provide the solid scraper rims. An extrusion-like profile-reducing rolling step provides dimensional accuracy to the finished strip which is then punched to provide the vent openings in the peripheral wall, and coiled and cut to form individual piston rings.