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:
Dec. 08, 1998
Filed:
Jul. 21, 1997
Gerhard Fraenkle, Remshalden, DE;
Klaus-Juergen Marquartdt, Remshalden, DE;
Daimler-Benz AG, , DE;
Abstract
A method and an apparatus for operating an internal combustion engine, in particular a motor-vehicle diesel engine, with low nitrogen-oxide emissions, has a first mode of operation which sets an early start of fuel injection and a nitrogen-oxide reducing agent is added to the stream of exhaust gases upstream of a nitrogen-oxide-reducing exhaust-gas catalytic converter, and a second mode of operation which sets a late start of fuel injection. A temperature sensor measures the temperature of the exhaust-gas catalytic converter. The engine is operated in the second mode of operation when the measured temperature of the exhaust-gas catalytic converter lies outside a prescribable temperature range for an effective catalytic nitrogen-oxide reduction to ensure low nitrogen-oxide emissions.