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:
Nov. 29, 2016
Filed:
Apr. 23, 2015
Nippon Piston Ring Co., Ltd., Saitama-shi, Saitama, JP;
Hiroyuki Sugiura, Saitama, JP;
Atsushi Chiba, Saitama, JP;
Makoto Kajiwara, Saitama, JP;
Kazuhiro Fujimura, Saitama, JP;
Katsuaki Ogawa, Saitama, JP;
Kazuhiro Sameshima, Saitama, JP;
Nippon Piston Ring Co., Ltd., Saitama-shi, JP;
Abstract
The second compression ring is formed such that the outer peripheral surface shape has a tapered face, and the radial cross-sectional shape is a rectangular ring, a scraper ring, or a Napier ring, and has a piston ring base and a hard film provided at least on an outer peripheral sliding surface thereof. The piston ring base is composed of a low-alloy steel or carbon steel having a Vickers hardness of Hv 350 Hv 550. The outer peripheral sliding surface is formed so that the axial length is from 0.01 to 0.30 mm between the outer edge end part of the tapered outer peripheral sliding surface and an imaginary line contacting with a lower end surface where a curved surface having a diameter that decreases gradually inward from the outer edge end part toward the lower end in the axial direction is parallel to a ring underside.