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:
Apr. 27, 2004
Filed:
Aug. 20, 2001
Hirofumi Nishimura, Hiroshima, JP;
Mazda Motor Corporation, Hiroshima, JP;
Abstract
An exhaust purifying system includes switching between a stratified combustion state at a stratified combustion region (I) of low revolutions speeds and low loads and a homogeneous combustion state of substantially the theoretical air/fuel ratio at a warm &lgr;=1 region (II) adjacent thereto with higher revolution speeds or loads, wherein a first oxygen concentration sensor is arranged upstream from the three-way catalyst, and when an engine shifts from the stratified combustion region (I) to the warm &lgr;=1 region (II), the feedback control of the air/fuel ratio based on an output signal of that sensor begins, and the target air/fuel ratio A/F is set to a range of 14.0≦A/F<14.7, so that the target air/fuel ratio A/E is slightly richer than the theoretical air/fuel ratio, thus preventing a temporary deterioration of the exhaust gas state.