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:
Jun. 24, 2009
Ataru Ichikawa, Kariya, JP;
Ataru Ichikawa, Kariya, JP;
Denso Corporation, Kariya, JP;
Abstract
An exhaust pipe is provided with a SCR catalyst (NOx catalyst) and an oxidation catalyst. A urea water adding valve and an exhaust gas temperature sensor are provided upstream of the SCR catalyst. A downstream NOx sensor is provided downstream of the SCR catalyst. The oxidation catalyst is provided with a catalyst temperature sensor. An ECU computes a temperature of the oxidation catalyst based on a detection value of the catalyst temperature sensor. Further, the ECU computes a temperature of exhaust gas flowing into the oxidation catalyst based on a detection value of the exhaust gas temperature sensor. The ECU detects ammonia flowing out from the SCR catalyst based on a differential temperature between the temperature of the catalyst and the temperature of the exhaust gas.