Method for identifying the state of an NOx storage catalyst

US6619108B2 · kind B2 · utility

Assignee

• Daimlerchrysler AG · US

Inventors

• Thomas Birkhofer · Immenstadt im Allgäu, DE
• Aleksandar Knezevic · Eitorf, DE
• Holger Leye · Unterensingen, DE
• Ralf Moos · Friedrichshafen, DE
• Carsten Plog · Markdorf, DE
• Thomas Ried · Bethesda, US
• Dirk Voigtlaender · Ditzingen, DE

Key dates

• Filing date: Dec 21, 2001
• Grant date: Sep 16, 2003
• Expiry date: Dec 21, 2021

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/40
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

In a method for identifying the state of an NOx storage catalyst which is cyclically loaded with NOx in the exhaust stream of an internal combustion engine and regenerated, two electrical defining quantities, independent of each other, of the electrically complex impedance of the NOx storage catalyst are detected, one of the two electrical quantities being a measure of the degree of loading of the NOx storage catalyst, and from the second electrical quantity the point in time being identifiable for the end of the regeneration process of the NOx storage catalyst.