Monitoring of a particle limit value in the exhaust gas of an internal combustion engine

Abstract

The invention relates to a method for diagnosing a particle filter used for filtering particles out of the exhaust gas of an internal combustion engine, wherein a collecting particle sensor is disposed downstream of the particle filter in the direction of flow of the exhaust gas and wherein a measurement for the loading of the particle sensor is determined from an output signal of the particle sensor. Provision is thereby made for the temporal integral of a parameter correlating to the particle emissions of the internal combustion engine to be formed during a measurement cycle, for the measurement for the loading of the particle sensor to be associated with the integral at least one measurement point in time during the measurement cycle and for a defective particle filter to be suggested if the measurement for the loading of the particle sensor is higher than a loading threshold value associated with the integral or if the integral is lower than an integral threshold value associated with the measurement for the loading of the particle sensor. The invention further relates to a device for carrying out the method. The method and the device allow for the diagnosis of the functionality of a particle filter in the exhaust gas of an internal combustion engine during any operating conditions passed through by the internal combustion engine.

Dependencies are inferred from the claim text.