Daimler-Benz Ag

Martin Bechtold

Friedrich Wirbeleit

Bernd Krutzsch

Klaus Wunderlich

Stefan Pischinger

The invention relates to a gasoline engine having a catalyst for reducing the emission pollutants, with an oxygen absorption device located in the exhaust line upstream of the catalyst. According to the invention, the gasoline engine is operated in a first operating range with a lean air/fuel ratio (.lambda.), and oxygen is removed from the exhaust by the absorption device. In a second operating range, the gasoline engine is operated at .lambda.=1, and the absorption device is bypassed or deactivated. In the case of a gasoline engine with a Denox catalyst the gasoline engine is operated constantly with a lean air/fuel ratio, with the active surface of the Denox catalyst being 'depoisoned' temporarily by activating the oxygen absorption device.

Exhaust arrangement for a gasoline

A reciprocating piston is disclosed with variable compression height for internal combustion engines in particular. For structural simplification of the temperature-dependent change in the compression height of the reciprocating piston, a spring is provided which consists of a shape memory alloy and interacts with the pressure limiting valve. This permits temperature-dependent change in the compression height of the reciprocating piston exclusively by the pressure limiting valve so that structural simplification is achieved.

Growing community of inventors

Stuttgart, Germany

Martin Bechtold