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. 09, 2010
Filed:
Apr. 27, 2007
Masakazu Yano, Ageo, JP;
Takayuki Adachi, Ageo, JP;
Masakazu Yano, Ageo, JP;
Takayuki Adachi, Ageo, JP;
Nissan Diesel Motor Co., Ltd., Ageo-shi, Saitama, JP;
Abstract
An exhaust gas purification apparatus includes an NOx reduction catalytic converter disposed in an engine exhaust passage to reductively purify NOx in exhaust gas using ammonia or its precursor as a reducing agent, a first concentration sensor which detects an ammonia concentration in an exhaust gas moving on a downstream side of the NOx reduction catalytic converter, and a control unit which incorporates therein a computer. The control unit conducts calculation to estimate an ammonia concentration in the exhaust gas moving on the downstream side of the NOx reduction catalytic converter, and when a difference between the ammonia concentration detected by the first concentration sensor and the estimated ammonia concentration by the calculation becomes larger than a first predetermined value, determines that the NOx reduction catalytic converter is deteriorated.