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:
Feb. 22, 2011
Filed:
Mar. 23, 2007
Kohei Yoshida, Gotenba, JP;
Kotaro Hayashi, Mishima, JP;
Kohei Yoshida, Gotenba, JP;
Kotaro Hayashi, Mishima, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
An internal combustion engine in which an SOtrap catalyst able to trap SOcontained in exhaust gas is arranged in an engine exhaust passage upstream of an NOstoring catalyst. The SOtrap catalyst is strengthened in basicity compared with the NOstoring catalyst to an extent so that when the temperature of the SOtrap catalyst is in the temperature range at the time of ordinary operation, that is, substantially 150° C. to substantially 400° C., the NOpurification rate by the SOtrap catalyst becomes less than substantially 10 percent of the NOpurification rate by the NOstoring catalyst. When NOshould be released from the NOstoring catalyst, the air-fuel ratio of the exhaust gas flowing into the SOtrap catalyst is temporarily switched from lean to rich.