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:
Oct. 01, 1991
Filed:
Sep. 07, 1990
Tsutomu Kimura, Kumagaya, JP;
Nippon Piston Ring Co., Ltd., Tokyo, JP;
Abstract
A two-piece type oil ring assembly consisting of a single spacer expander in the form of a split annulus and a side rail in the form of a flat split annulus. The spacer expander has a flat lower surface for making plane contact with the lower side of an oil ring groove when the assembly is mounted in the oil groove of a piston. The spacer expander has a radially, substantially L-shaped section composed of a trough portion, an outer crest portion integrally connected to the trough portion from outside, and an inner crest portion integrally connected to the trough portion from inside, the inner crest portion being taller than the outer crest portion. The spacer expander has a multiplicity of radial slots extending alternatively from the inner periphery of the inner crest portion to the inner periphery of the outer crest portion and from the outer periphery of the outer crest portion to the outer periphery of the inner crest portion. A plurality of oil grooves pass radially through the spacer expander. The lower surface of the side rail is placed on the outer crest portion while the inner periphery of the side rail is supported by the slanting surface of the inner crest portion.