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. 20, 2001
Filed:
May. 31, 2000
Teruo Takahashi, Tochigi-ken, JP;
Hiroshi Oshige, Tochigi-ken, JP;
Nippon Piston Ring Co., Ltd., , JP;
Abstract
An internal combustion engine includes, in combination, an intake side valve system and an exhaust side valve system. Each of the valve systems comprises a valve seat and a valve member to be assembled with the valve seat, in which the valve seat has a base member including a matrix of iron-base sintered alloy and a dispersed Si—Cr—Mo—Co group intermetallic compound powder, the intermetailic compound powder having a hardness of Hv600 to Hv1000 and an average particle diameter of 20 to 70 &mgr;m, the matrix being contained at 10 to 50 mass % with reference to total mass of the base member, and the valve member has a base member including a matrix of martensitic steel and a nitriding diffusion layer formed to a valve face of the base member, the nitriding diffusion layer having a hardness of more than Hv500 and a thickness of more than 20 &mgr;m.