Method and device for regulating the temperature range of an NOx accumulator in an exhaust system of an internal combustion engine

Abstract

A method and a device for controlling the temperature of an NOx accumulator to purify the exhaust gas stream of an internal combustion engine, can be used especially for diesel or lean-burn engines. A heat flow is carried off from the exhaust gas stream upstream of the NOx accumulator in the exhaust gas line depending on the operating state of the internal combustion engine, so that a maximum temperature of the NOx accumulator is not exceeded and more particularly so that a specified temperature range is maintained. In order to obtain a minimum operating temperature of the NOx accumulator, the internal combustion engine is operated at least at an air-fuel ratio of λ≦1 until the minimum operating temperature is reached.

Dependencies are inferred from the claim text.