Abstract: In a method for operating an internal combustion engine comprising at least one a cylinder with a combustion chamber, wherein by means of at least one detection device assigned to the combustion chamber a first value characterizing the pressure in the combustion chamber is detected, wherein on the basis of the first value at least a second value characterizing a progression of the energy released during a combustion in the combustion chamber is determined, on the basis of the second value at least a third value is determined, by means of which the progression of the combustion is subdivided into at least two sub-curves and one of the sub-curves is assigned to a normal combustion for operation of the internal combustion engine and the other of the sub-curves is assigned to a special combustion differing from the normal combustion.

Abstract: In a method for operating an exhaust-gas cleaning unit of a diesel engine including a particle filter and a nitrogen oxide storage device arranged upstream of the particle filter, wherein sulfur regeneration of the nitrogen oxide storage device is performed periodically at raised exhaust gas temperatures and, in certain phases, with a rich exhaust gas composition, and also soot regeneration of the particle filter is performed at raised exhaust gas temperatures with a lean exhaust gas composition, at least some of the sulfur regeneration and the soot regeneration phases are performed in a combined soot and sulfur regeneration phase, and for the sulfur regeneration, at least temporarily, a rich exhaust-gas composition with a temperature higher than the temperature of the lean exhaust gas composition is provided for the soot regeneration of the particle filter.

Abstract: In a method for operating an exhaust-gas cleaning unit of a diesel engine including a particle filter and a nitrogen oxide storage device arranged upstream of the particle filter, wherein sulfur regeneration of the nitrogen oxide storage device is performed periodically at raised exhaust gas temperatures and, in certain phases, with a rich exhaust gas composition, and also soot regeneration of the particle filter is performed at raised exhaust gas temperatures with a lean exhaust gas composition, at least some of the sulfur regeneration and the soot regeneration phases are performed in a combined soot and sulfur regeneration phase, and for the sulfur regeneration, at least temporarily, a rich exhaust-gas composition with a temperature higher than the temperature of the lean exhaust gas composition is provided for the soot regeneration of the particle filter.

Abstract: The invention relates to a method for operating a diesel engine in which an air ratio (?) of the fuel which is to be burnt and of the combustion air supplied is set by a control unit (14) according to predetermined values. When a value (15) which is predetermined as a switching criterion is recorded, the control unit (14) switches to a special operating mode for regeneration of a catalytic converter (22) and sets the fuel/air ratio according to predetermined values for this operating mode. To achieve more effective regeneration of the catalytic converter, according to the invention it is provided that at least one afterinjection, which is separated in time from a main injection, of fuel which is also to be burnt takes place in the special operating mode.

Abstract: An Exhaust-gas purification system for an internal combustion engine, which, as seen in the direction of flow of the exhaust gas, has a particle filter, apparatus for providing a reducing agent in the exhaust-gas flow, a catalytic converter for reducing nitrogen oxide which is present in the exhaust gas, and a downstream oxidation catalytic converter. An upstream oxidation catalytic converter is arranged upstream of the particle filter.

Abstract: In a method for operating a diesel engine and a diesel engine, wherein engine emission control is provided by switching between a lean mode with superstoichiometric combustion air ratio ?>1 and a rich mode with substoichiometric combustion air ratio ?<1, the engine-torque fluctuations during the switching are determined and engine parameters which influence the engine torque, are adjusted so as to keep the engine torque constant during the switchover.

Abstract: In a method for operating an internal combustion engine using exhaust gas purification system, and internal combustion engine, the method for operating an internal combustion engine with exhaust gas purification system, in which a rich mode of the internal combustion engine with a rich exhaust gas composition and a lean mode of the internal combustion engine with a lean exhaust gas composition are set alternately, and by the exhaust gas purification system with a rich exhaust gas composition ammonia is synthesized and stored and with a lean exhaust gas composition nitrogen oxides are reduced to form nitrogen by means of the stored ammonia.

Abstract: An Exhaust-gas purification system for an internal combustion engine, which, as seen in the direction of flow of the exhaust gas, has a particle filter, apparatus for providing a reducing agent in the exhaust-gas flow, a catalytic converter for reducing nitrogen oxide which is present in the exhaust gas, and a downstream oxidation catalytic converter. An upstream oxidation catalytic converter is arranged upstream of the particle filter.

Abstract: The invention relates to a method for operating a diesel engine in which an air ratio (&lgr;) of the fuel which is to be burnt and of the combustion air supplied is set by a control unit (14) according to predetermined values. When a value (15) which is predetermined as a switching criterion is recorded, the control unit (14) switches to a special operating mode for regeneration of a catalytic converter (22) and sets the fuel/air ratio according to predetermined values for this operating mode.

Abstract: In a method for operating a combustion engine having an exhaust-gas turbocharger, it is possible to switch over between a normal operation and a special operation. In the special operation, at least one main fuel injection and at least one secondary fuel injection are provided. In response to a positive load jump, a switch-over between the normal operation and the special operation provided for increasing the exhaust gas enthalpy is performed, the secondary fuel injection in the special operation being adjusted so that it substantially burns in the combustion chamber and causes an increase in the exhaust gas enthalpy as well as an adjustment of a rich or a lean exhaust gas composition. The method according to the present invention may be used, for example, in a motor vehicle having a diesel engine.

Abstract: In a method for operating a diesel engine and a diesel engine, wherein engine emission control is provided by switching between a lean mode with superstoichiometric combustion air ratio &lgr;>1 and a rich mode with substoichiometric combustion air ratio &lgr;<1, the engine-torque fluctuations during the switching are determined and engine parameters which influence the engine torque, are adjusted so as to keep the engine torque constant during the switchover.

Abstract: In a method for operating an internal combustion engine using exhaust gas purification system, and internal combustion engine, the method for operating an internal combustion engine with exhaust gas purification system, in which a rich mode of the internal combustion engine with a rich exhaust gas composition and a lean mode of the internal combustion engine with a lean exhaust gas composition are set alternately, and by the exhaust gas purification system with a rich exhaust gas composition ammonia is synthesized and stored and with a lean exhaust gas composition nitrogen oxides are reduced to form nitrogen by means of the stored ammonia.

Abstract: An exhaust-gas cleaning unit includes a particle filter and a nitrogen oxide store disposed upstream of the particle filter. A method for operating the exhaust-gas cleaning unit includes a nitrogen oxide regeneration phase and a sulphur regeneration phase for the nitrogen oxide store and a soot regeneration phase for the particle filter. A longer period is selected for the sulphur regeneration phase than for the nitrogen oxide regeneration phase. At least part of the sulphur regeneration phase and at least part of the soot regeneration phase are performed as a combined regeneration phase, in which the regeneration phases are performed in immediate succession or one regeneration phase is performed intermittently at a number of intervals during the other regeneration phase.

Abstract: In a method for operating a combustion engine having an exhaust-gas turbocharger, it is possible to switch over between a normal operation and a special operation. In the special operation, at least one main fuel injection and at least one secondary fuel injection are provided. In response to a positive load jump, a switch-over between the normal operation and the special operation provided for increasing the exhaust gas enthalpy is performed, the secondary fuel injection in the special operation being adjusted so that it substantially burns in the combustion chamber and causes an increase in the exhaust gas enthalpy as well as an adjustment of a rich or a lean exhaust gas composition. The method according to the present invention may be used, for example, in a motor vehicle having a diesel engine.

Abstract: The invention relates to a method of operating a diesel engine having an engine controller which controls the operation of the diesel engine as a function of characteristic maps and permits rich/lean control of the diesel engine. The engine controller includes a computer which effects a changeover to rich or lean operation of the diesel engine as a function of predetermined changeover criteria, a sensor system which communicates with the computer and monitors parameters needed for changeover criteria, and a memory which communicates with the computer and in which the characteristic maps for operating the diesel engine are stored. The computer effects a changeover from lean to rich operation when all the changeover criteria in this respect are satisfied, and effects a change back from rich to lean operation when at least one of the changeover criteria in this respect is satisfied.

Abstract: A system and a process for operating a diesel engine using an automatic engine control which, as a function of characteristic diagrams, automatically controls the operation of the diesel engine and permits an automatic rich/lean controlling of the diesel engine. The automatic engine control includes a computer which, as a function of predetermined change-over criteria, causes a change-over to the rich or the lean operation of the diesel engine. A sensor system communicates with the computer and monitors the parameters necessary for change-over criteria. A memory communicates with the computer, the memory storing separate characteristic diagrams for the operation of the diesel engine for the lean operation and for the rich operation.