Diesel engine with an exhaust-gas filter

US5138835A · kind A · utility

Assignee

• Mercedes-Benz Group AG · DE

Inventors

• Franz Bender · Wissen, DE
• Dirk Naber · Stuttgart, DE

Key dates

• Filing date: May 23, 1991
• Grant date: Aug 18, 1992
• Expiry date: May 23, 2011

Classification

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

Abstract

In an internal-combustion engine, in particular a diesel engine, with an exhaust-gas filter and an exhaust gas recirculation, the exhaust counter-pressure prevailing upstream of the exhaust-gas filter is used as one of a number of controlled variables for automatically controlling the exhaust gas recirculation. Since the exhaust-gas filter experiences flow resistance variations, particularly if it is a soot burn-off filter, which variations are independent of engine operation and consequently falsify the automatic control of the exhaust gas recirculation, the respective instantaneous exhaust-gas filter flow resistance must be measured as a correcting quantity and taken into account. A measuring device is fitted into a bypass line bridging the exhaust-gas filter and operates with a negligible bypass flow such that, above a predeterminable upper exhaust-gas filter differential pressure, it can lead past the exhaust-gas filter an increased bypass flow, which can, if appropriate, correspond to the entire exhaust flow.