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. 19, 2002
Filed:
Dec. 26, 2000
Corinna Pfleger, Donaustauf, DE;
Hong Zhang, Tegernheim, DE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
In a method for regenerating a NOx storage catalytic converter disposed in an engine exhaust operating with air excess, in operating ranges, the improvement includes storing NOx in the exhaust gas in the converter in a storage phase and catalytically converting the stored NOx in a regeneration phase. The signal of the NOx sensor disposed downstream of the converter is detected in the operating range of the overrun fuel cut-off and an average/minimum value is formed from the individual measured values. The average/minimum value is stored as an offset value of the sensor signal. In operating ranges beyond the engine overrun fuel cut-off, the signal of the NOx sensor is detected and the offset value is taken into account when the signal is processed further, in that the offset-corrected signal is compared with a threshold value. In the event that the threshold value is exceeded, a regeneration phase of the converter is initiated.