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:
Aug. 07, 2001
Filed:
Jan. 29, 1999
Motonobu Onoda, Yono, JP;
Takao Sakai, Yono, JP;
Nippon Piston Ring Co., Ltd., Saitama-ken, JP;
Abstract
A piston ring combination including at least one compression ring and at least one oil ring. If a plurality of compression rings are provided, an outer peripheral surface of at least a top ring is formed with a first ion plating layer. The oil ring has a pair of side rails whose outer peripheral surfaces are formed with second ion plating layers. These layers are formed of Cr—N mixture. The first ion plating layer has a porous structure with a porosity ranging from 3 to 10% and a hardness ranging from 1000 to 1500 Hv. The second ion plating layer has a dense structure with a porosity ranging from 0 to 3% and a hardness ranging from 1800 to 2200 Hv.