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. 22, 2013
Filed:
Apr. 16, 2008
Daiji Nagaoka, Fujisawa, JP;
Masashi Gabe, Fujisawa, JP;
Hiroyuki Yuza, Fujisawa, JP;
Isuzu Motors Limited, Tokyo, JP;
Abstract
An NOx purification system having a selective reduction catalyst, adapted so that even when no ammonia or urea is supplied, NOx is converted to ammonia by a first catalyst including a lean NOx catalyst or a ternary catalyst at ammonia formation control and the ammonia is adsorbed by the selective reduction catalyst disposed downstream and so that by the adsorbed ammonia, there is carried out reduction purification of the NOx contained in the exhaust gas when no ammonia formation control is performed by the selective reduction catalyst. At the ammonia formation control, an ammonia adsorption target amount being a target value of ammonia adsorbed by the selective reduction catalyst is computed, and the ammonia formation control is carried out only when a cumulative value of an ammonia formation amount formed by the first catalyst at the ammonia formation control is under the ammonia adsorption target amount. Consequently, ammonia is stably supplied in just proportion to the selective reduction catalyst.