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:
Mar. 05, 2002
Filed:
Sep. 11, 2000
Mazda Motor Corporation, Hiroshima-Ken, JP;
Abstract
A direct injection engine of sparking ignition type has a catalyst in an exhaust passage and a fuel injection valve for directly spraying fuel into a combustion chamber. An ECU for controlling the engine is provided with a setter and an air-fuel ratio controller. The setter sets an enriched region where an air-fuel ratio is smaller than a stoichimetric air-fuel ratio in a high engine speed and load area of an operating region of the engine, a stoichimetric air-fuel ratio region where the air-fuel ratio is equal to the stoichimetric air-fuel ratio in an area of the operating region of the engine having lower engine speed or load than the enriched region, and a lean region where the air-fuel ratio is larger than the stoichimetric air-fuel ratio between the stoichimetric air-fuel ratio region and the enriched region. The air-fuel ratio controller controls the air-fuel ratio based on the setting by the setter. Accordingly, a rise in exhaust gas temperature can be suppressed in the operating region having high engine speed and load, thereby significantly improving fuel consumption at high speeds while ensuring reliability.