Method for monitoring the catalytic activity of a catalytic converter in the exhaust gas system of an internal combustion engine

US5428956A · kind A · utility

Assignee

• EMITEC Gesellschaft fuer Emissionstechnologie mbH · DE

Inventors

• Wolfgang Maus · Bensberg, DE
• Helmut Swars · Bensberg, DE
• Rolf Brück · Bensberg, DE

Key dates

• Filing date: May 23, 1994
• Grant date: Jul 4, 1995
• Expiry date: May 23, 2014

Classification

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

Abstract

A method for monitoring catalytic activity of a catalytic converter through which exhaust gas can flow in an exhaust system of an internal combustion engine includes measuring a temperature at least at two temperature measuring sensors and periodically repeatedly determining a temperature measuring variable from signals issued by the sensors during operation of the engine with an engine monitoring system. Further measuring variables characterizing an applicable operating state of the engine are determined, a temperature limit value is determined from the further measuring variables, catalytic activity is determined by comparing the temperature measuring variable with the temperature limit value, and a report is issued if the temperature measuring variable is lower than the temperature limit value.