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:
Jan. 10, 2012
Filed:
Mar. 06, 2008
Hiroshi Sawada, Gotenba, JP;
Shinichiro Imamura, Chiryu, JP;
Hiroshi Sawada, Gotenba, JP;
Shinichiro Imamura, Chiryu, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Denso Corporation, Kariya, JP;
Abstract
An NOx catalyst of storage reduction type and an after-catalyst NOx sensor are provided in an exhaust passage in an internal combustion engine. The after-catalyst NOx sensor detects the NOx concentration on the downstream side of the NOx catalyst. The NOx concentration on the upstream side of the NOx catalyst is detected or estimated. The possible abnormality of the after-catalyst NOx sensor is determined by comparing the NOx concentration on the upstream side of the NOx catalyst detected or estimated and the NOx concentration detected by the after-catalyst NOx sensor, under the condition that the NOx catalyst does not substantially absorb NOx in exhaust gas. Abnormality diagnosis is performed with the possible impact of the NOx catalyst inhibited.