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. 23, 2025
Filed:
Mar. 13, 2024
Applicant:
Kobe Steel, Ltd., Hyogo, JP;
Inventors:
Hirotaka Ito, Kobe, JP;
Yuya Murata, Kobe, JP;
Takumi Kitayama, Kobe, JP;
Naofumi Kanei, Takasago, JP;
Assignee:
KOBE STEEL, LTD., Hyogo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16J 9/12 (2006.01); F04B 39/00 (2006.01); F04B 53/14 (2006.01);
U.S. Cl.
CPC ...
F16J 9/12 (2013.01); F04B 39/0005 (2013.01); F04B 53/143 (2013.01);
Abstract
A piston ring is a piston ring for use in an oil-free-type reciprocating compressor for compressing hydrogen gas, the piston ring containing thermoplastic polyimide as a main component and carbon fiber and/or graphite as an additive, and having a tensile strength of 90 MPa or more and a bending strength of 150 MPa or more.