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. 08, 2006
Filed:
Sep. 27, 2002
Yutaka Mabuchi, Yokohama, JP;
Yoshiteru Yasuda, Yokohama, JP;
Masahiko Shioda, Yokohama, JP;
Mototaka Ishihara, Yokohama, JP;
Hisanori Ohara, Hyogo, JP;
Kazuhiko Oda, Hyogo, JP;
Yoshiharu Utsumi, Kyoto, JP;
Miki Irie, Hyogo, JP;
Yutaka Mabuchi, Yokohama, JP;
Yoshiteru Yasuda, Yokohama, JP;
Masahiko Shioda, Yokohama, JP;
Mototaka Ishihara, Yokohama, JP;
Hisanori Ohara, Hyogo, JP;
Kazuhiko Oda, Hyogo, JP;
Yoshiharu Utsumi, Kyoto, JP;
Miki Irie, Hyogo, JP;
Nissan Motor Co., Ltd., Yokohama, JP;
Abstract
Disclosed is a shim or a valve lifter for an automotive engine valve driving system that slides against a cam lobe of a camshaft to drive an intake/exhaust valve of an internal combustion engine. The shim or lifter has the top of a sliding surface thereof opposing the cam lobe and being coated with a hard carbon film. The hard carbon film has a surface hardness of 1500 to 4500 kg/mmin terms of Knoop hardness, a thickness of 0.3 to 2.0 μm and a surface roughness Ry (μm) satisfying the following equation (A):<{(0.75−/8000)×  (A)where h is the thickness (μm) of the hard carbon film; and Hk is the knoop hardness (kg/mm) of the hard carbon film. By imparting durability, reliability and a low friction coefficient to the hard carbon film that is said to be low in ductility to prevent the hard carbon film from becoming cracked and separated when applied to the sliding portion.