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:
May. 09, 1995
Filed:
Dec. 27, 1993
Kiyotaka Mamiya, Hiroshima, JP;
Tohru Shiraishi, Hiroshima, JP;
Katuhiro Yokomizo, Hiroshima, JP;
Takafumi Teramoto, Hiroshima, JP;
Mazda Motor Corporation, Hiroshima, JP;
Abstract
An air-fuel ratio control system for a gaseous fuel engine which runs on gaseous fuel containing at least partly hydrogen gas has a fuel supply control valve which adjusts the amount of the gaseous fuel supplied to the engine and a control unit which controls the fuel supply control valve to control the air-fuel ratio according to the engine load. The control unit controls the fuel supply control valve so that the air-fuel ratio becomes higher than a NOx-maximizing air-fuel ratio, at which the amount of NOx emitted from the engine is maximized, in a predetermined operating range of the engine, and in the predetermined operating range of the engine, the control unit controls the fuel supply control valve so that the air-fuel ratio becomes higher in a high engine speed range than in a low engine speed range.