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. 11, 2017
Filed:
Feb. 08, 2016
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, Aichi-ken, JP;
TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota-Shi, JP;
Abstract
A deterioration diagnosis device for an exhaust gas purification apparatus which performs inducement processing when the internal combustion engine is operated at a lean air fuel ratio, measures, by means of air fuel ratio sensors, the air fuel ratio of exhaust gas flowing into the SCR catalyst and the air fuel ratio of exhaust gas flowing out from the SCR catalyst during a period while the inducement processing is performed, and diagnoses deterioration of the SCR catalyst based on a difference between the measured values of these sensors, wherein an amount of hydrogen produced by each of a three-way catalyst and an NSR catalyst is estimated based on the deterioration degree thereof, and an air fuel ratio of exhaust gas discharged from the internal combustion engine is feedback-controlled so that the air fuel ratio of the exhaust gas flowing into one of the three-way catalyst and the NSR catalyst in which the hydrogen production amount thus estimated is larger than that in the other becomes a target value.