Abstract: The invention relates to a method for generating an ion current which occurs as a direct current between a central electrode and one or more side electrodes of a spark plug of a spark ignition engine which is supplied repeatedly with an ignition voltage from an ignition voltage source, wherein the spark ignition engine is assigned an engine control unit, which, in an engine cycle, determines for each spark plug a target ignition point and/or an activation point for the ignition voltage source before the target ignition point, and a second voltage source is provided, which delivers a second voltage for the generation of the ion current, wherein the second voltage source lying in the engine cycle for a first time interval ?t1, which is shorter than the duration of the engine cycle, is connected to the electrodes of the spark plug, and wherein the ion current flowing as a result of the application of the second voltage to the electrodes of the spark plug takes a path which avoids the ignition voltage source.

Abstract: The invention relates to a method for generating an ion current which occurs as a direct current between a central electrode and one or more side electrodes of a spark plug of a spark ignition engine which is supplied repeatedly with an ignition voltage from an ignition voltage source, wherein the spark ignition engine is assigned an engine control unit, which, in an engine cycle, determines for each spark plug a target ignition point and/or an activation point for the ignition voltage source before the target ignition point, and a second voltage source is provided, which delivers a second voltage for the generation of the ion current, wherein the second voltage source lying in the engine cycle for a first time interval ?t1, which is shorter than the duration of the engine cycle, is connected to the electrodes of the spark plug, and wherein the ion current flowing as a result of the application of the second voltage to the electrodes of the spark plug takes a path which avoids the ignition voltage source.

Abstract: A measuring arrangement is provided with a soot filter for use in flowing, soot particle-bearing gases, as well as a method for monitoring the operability of a soot filter arranged in an exhaust gas conduit, wherein at least one component stream of an exhaust gas stream flows through at least one molded element which is open-pored at least in the flow direction, and wherein the temperature of the molded element is measured with at least one temperature probe. In the measuring arrangement the soot filter is allocated at least one soot sensor, which has at least one molded element which is openpored at least in the flow direction, at least one electric heating element, and at least one temperature probe. The measuring arrangement and method make possible a monitoring of the operability of a soot filter in a reliable and direct manner.

Abstract: A gas sensor is provided for measurement of oxygen and/or the air-to-fuel lambda ratio and hydrocarbons and/or carbon monoxide in gas mixtures. To reliably measure a plurality of gaseous components, the sensor is provided with a reference electrode representing a constant oxygen partial pressure, an oxygen ion-conducting solid electrolyte, and at least two measuring electrodes, the measuring electrodes and the reference electrode being mounted directly on the solid electrolyte and having electrical leads for connection and for take-away of electrical measurement signals. The solid electrolyte (1) is constructed with a measurement gas side exposed to the gas mixture and a reference gas side separated from the gas mixture.

Abstract: A method of measuring oxygen and/or the air-to-fuel lambda ratio and hydrocarbons and/or carbon monoxide in gas mixtures using a gas sensor is provided. To reliably measure a plurality of gaseous components, the sensor is provided with a reference electrode representing a constant oxygen partial pressure, an oxygen ion-conducting solid electrolyte, and at least two measuring electrodes, the measuring electrodes and the reference electrode being mounted directly on the solid electrolyte and having electrical leads for connection and for take-away of electrical measurement signals. The solid electrolyte is constructed with a measurement gas side exposed to the gas mixture and a reference gas side separated from the gas mixture.