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:
Sep. 06, 2005
Filed:
Aug. 07, 2003
Wei LI, Troy, MI (US);
David R. Monroe, Bloomfield Hills, MI (US);
Wei Li, Troy, MI (US);
David R. Monroe, Bloomfield Hills, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
An apparatus and a method for removing NOx from an exhaust stream of a lean-burn engine during an engine cold start are provided. The apparatus includes a close-coupled LNT coupled to a main LNT by a hollow conduit. NOx from the cold exhaust is initially stored on the close-coupled LNT. As the engine exhaust warms up, the close-coupled LNT reaches its operating temperature and reduces the stored NOx to N. When the temperature of the close-coupled LNT reaches approximately 350° C., NOx is released from the close-coupled LNT, is absorbed on the main LNT, and is converted to Nduring fuel-rich conditions, The close-coupled LNT can be regenerated after the engine is turned off by providing heat. The released NOx during the regeneration of the closed-coupled LNT is absorbed by the main LNT. The stored NOx on the main LNT can be reduced to Nduring the next vehicle operation.