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. 21, 2010
Filed:
Jun. 04, 2008
Sanjeev M. Naik, Troy, MI (US);
David J. Cleary, West Bloomfield, MI (US);
Sanjeev M. Naik, Troy, MI (US);
David J. Cleary, West Bloomfield, MI (US);
GM Global Technology Operations, Inc., Detroit, MI (US);
Abstract
A method for controlling regeneration of a lean NOx trap includes estimating an accumulated NOx in the lean NOx trap; determining whether the estimated NOx exceeds a first threshold value or a second threshold value; estimating the temperature of the lean NOx trap; determining whether the estimated temperature exceeds a threshold temperature; determining a desired air-fuel ratio for initiating a regeneration event, the desired air-fuel ratio being determined based upon the estimated NOx and the estimated temperature of the lean NOx trap; hastening the occurrence of a regeneration event when the estimated NOx exceeds the first threshold value through active control of engine operating regimes; and initiating a regeneration event when the estimated NOx exceeds the second threshold value or when the estimated temperature exceeds the threshold temperature by forcing homogenous operation of the engine at the desired air-fuel ratio.