Daimler-benz Ag

Daimler Chrysler Ag

Mercedes-benz Aktiengesellschaft

Purem Abgassysteme Gmbh & Co. Kg

Klaus Binder

Bernd Krutzsch

Michel Weibel

Andreas Hertzberg

Brigitte Konrad

Stefan Renfftlen

Rolf Wunsch

Marko Weirich

Erwin Eisele

Ulrich Augustin

Friedrich Wirbeleit

Carsten Plog

Patrick Izquierdo

Alois Raab

Ralf Moos

Michael-Rainer Busch

Hermann Hiereth

Viktor Pfeffer

Georg Huthwohl

Bernd Maurer

Tillmann Braun

Aleksandar Knezevic

Shoichi Furuhama

Gerhard Fraenkle

Dirk Voigtl&auml;nder

Günter Wenninger

Josef G&uuml;nther

Karl-Ludwig Weisskopf

Rainer Werner Jorach

Alexander Funk

G&uuml;nter Wenninger

Dirk Voigtländer

Peter Ebel

Klaus-Juergen Marquardt

Heinz-Jost Ölschlegel

Heinz-Jost &Ouml;lschlegel

Klaus Drexl

Peter Charzinski

Harald Polz

Hans-Peter Charzinski

Gerd Seidel

Ansgar Schaefer

Josef Günther

Klaus-J&uuml;rgen Marquardt

An internal combustion engine includes an exhaust-gas aftertreatment device, and an operating method is for operating the internal combustion engine. The internal combustion engine is operable with a lean mixture and a rich mixture, the internal combustion engine having an exhaust-gas aftertreatment device, which includes a nitrogen oxide storage catalytic converter and a particle filter. When lean exhaust gas flows through the nitrogen oxide storage catalytic converter, it removes nitrogen oxides from the exhaust gas by storing them, and, when reducing exhaust gas flows through the nitrogen oxide storage catalytic converter, it produces ammonia through reduction of stored and/or supplied nitrogen oxides and releases it to the exhaust gas. Downstream from the nitrogen oxide storage catalytic converter, the exhaust-gas aftertreatment device includes a SCR catalytic converter, which reduces nitrogen oxides contained in the exhaust gas, using ammonia produced by the nitrogen oxide storage catalytic converter.

Exhaust-gas aftertreatment device with nitrogen oxide storage catalytic converter, and operating method therefor

A device for exhaust-gas purification utilizes reduction of nitrogen oxides which are present in the exhaust gas from internal combustion engines by way of gaseous ammonia with an SCR catalytic converter. The functions of the device are monitored with regard to their line paths with connections, valves and sensors by referring to these elements themselves using suitable control circuitry via the evaluation and control unit.

Device for exhaust-gas purification, and an operating and monitoring for said device

A method for determining the storage state of an ammonia-storing SCR catalyst, the change in at least one physical property of the SCR catalyst material, changing with the NH storing process, being sensed, the measurement taking place on the SCR catalyst material itself by applying a measuring pickup to the SCR catalyst or bringing it into direct contact with the latter and determining the storage state on the basis of these results. In an alternative embodiment, a material identical or similar to the SCR catalyst material with regard to its physical properties is arranged in the exhaust-gas stream in addition to the SCR catalyst material, and the change in at least one physical property of this substitute material changing with the NH storing process, is sensed, the measurement taking place on the substitute material itself by applying the substitute material to the measuring pickup or bringing it into direct contact with the latter and determining the storage state of the SCR catalyst on the basis of these results.

Method and apparatus for determining the storage state of an ammonia-storing SCR catalyst

An exhaust-gas aftertreatment device with a nitrogen oxide storage catalytic converter for an internal combustion engine, and a method for operating an exhaust-gas aftertreatment device which is assigned to an internal combustion engine and has a nitrogen oxide storage catalytic converter. An SCR catalytic converter is arranged in the exhaust-gas aftertreatment device, it being possible for the exhaust gas which emerges from the nitrogen oxide storage catalytic converter to be fed to the SCR catalytic converter when the internal combustion engine is in a desulphating operating mode with a reducing exhaust-gas composition, in order for H S which is formed during the desulphating to be removed. When the internal combustion engine is in a desulphating operating mode, the following steps are performed: establishing a reducing exhaust gas composition upstream of the nitrogen oxide storage catalytic converter; releasing the sulphur which is bound in the nitrogen oxide storage catalytic converter, to form hydrogen sulphide (H S); feeding the hydrogen sulphide to an SCR catalytic converter which is arranged downstream of the nitrogen oxide storage catalytic converter in the exhaust-gas aftertreatment device; and reacting the hydrogen sulphide in the SCR catalytic converter to form sulphur dioxide under reducing exhaust-gas conditions. The method may be used in motor vehicles, e.g., passenger cars, with lean-burn internal combustion engines.

This invention provides a porous thermal barrier layer for protecting parts of an internal-combustion engine having parts which are acted upon by combustion, and particularly by heat, and to a process for applying such a thermal barrier layer to these parts. The thermal barrier layer, which is formed of grains and/or fibers connected with one another on the exterior side, and is produced at least partially from a heat-resistant, temperature-shock-stable and abrasion-proof barrier material, has a heat penetration number defined by the following formula

Internal-combustion engine and process for applying a thermal barrier

In a fuel injection nozzle for an internal combustion engine with a fuel injection opening including a nozzle opening control needle with a body portion with discharge openings whose size depends on the axial displacement of the nozzle opening control needle and with means for limiting the axial displacement of the nozzle opening control needle, a hollow nozzle needle is disposed around the stem of the nozzle opening control needle and forms at its end a fuel control valve seat for controlling fuel flow to the fuel injection opening and a control space is provided at the end of the hollow nozzle needle opposite its valve seat which is in communication with a pressurized fuel supply for holding the hollow nozzle needle in a seated position but from which the pressure can be released to permit lifting of the hollow nozzle needle by pressurized fuel supplied to the seating area end of the hollow nozzle needle whereupon the pressurized fuel released through the fuel control valve displaces the nozzle opening control needle to open the discharge opening as permitted by limiting mechanism.

Fuel injection nozzle for an internal combustion engine

A gas-injection valve for injecting gaseous fuel into the combustion chamber of an internal combustion engine, comprising a valve housing and, disposed therein, a longitudinally displaceable piston having connected thereto a poppet valve for controlling an injection port, which poppet valve opens in the direction of gas flow, said piston separating a gas space from an operating space adapted to be pressurized by having hydraulic control fluid fed thereto by a pressure pump, and the gas pressure within the gas space alone being sufficient to move the poppet valve to and to hold it in its closed position when the operating space is depressurized.

Gas-injection valve for internal combustion engine

The invention relates to a piston having a variable compression height and two control chambers connected to each other through a hydraulic system. In order to achieve better cold-start and warm-up behavior, an oil discharge bore from the upper control chamber into the crankcase is closed by a control slide valve in the cold operating state of the engine. The blockage of the oil discharge produces a great compression height and therefore high compression. The control slide valve is connected to an expansible element which maintains it in this closed position when the engine is cold. As the engine warms up, the expansible element, due to its thermal expansion, pushes the control slide valve out of its closed position, so that the discharge of oil can occur progressively more unthrottled with rising temperature. In the warm operating state of the engine the control slide valve clears the oil discharge duct completely, and an unobstructed discharge of oil is ensured.

Temperature-sensitive variation of the compression ratio in pistons

A process is described for producing a diesel fuel/water emulsion for a diesel engine in which, as a function of the operating condition of the engine, water and diesel fuel are mixed at different quantitative proportions and supplied to the engine. The water and the diesel fuel separately are led practically to the intake side of the injection pump and are mixed only in the pump cylinder. The non-injected highly pressurized excess quantity of fuel is stored temporarily in an accumulator and is again supplied to the injection pump during the next intake stroke. The process makes it possible to produce a very fine water/fuel mixture and in addition to keep the volume of the fnished water/fuel mixture low, so that when the quantitative proportion is changed because of the inertia of the system, the new fuel/water mixture is available at the point of consumption (injection nozzle).

Process for producing a diesel-fuel/water emulsion for a diesel engine

An internal combustion engine operating with self-ignition which is equipped with a main combustion space including a piston recess and with an auxiliary chamber arranged in the cylinder head an injection nozzle is coordinated to the auxiliary chamber while the chamber includes an insert forming an overflow channel provided with several discharge holes terminating in the main combustion space. The discharge holes are matched as regards their direction and cross section to the main combustion space-air volume component to be seized or impinged upon by the respective jet passing through the corresponding discharge hole. The discharge holes are thereby proportional in cross section to the main combustion space-air volume component located in front thereof when the piston is in a position corresponding to the center point of the full-load heat-release curve and are directed toward the center of gravity of the respective main combustion space-air volume component.

Internal combustion engine

An air-compressing injection internal combustion engine with a main combustion space arranged in the piston and with an auxiliary chamber equipped with an injection nozzle and with a glow plug, which is in continuous communication with the main combustion space by way of a channel-shaped constriction. The pressure chamber of the auxiliary chamber is thereby disposed eccentrically in relation to the injection nozzle and the constriction while the injection nozzle injects with a first jet into the constriction and with a second jet in the direction or into the area near the glow plug which is located in the eccentrically offset part of the pressure chamber.

Air-compressing injection internal combustion engine with auxiliary

A combustion process for a reciprocating piston internal combustion engine with applied ignition and operating with hydrogen injection as well as an internal combustion engine capable of carrying out the process, in which the air is supplied independently of the hydrogen and an air ring rotating about the cylinder axis is produced which has a density increasing radially outwardly; the injection of the hydrogen into the air ring thereby takes place into the central area of the air ring while ignition takes place within the transition area between the central hydrogen core and the externally rotating air ring.

Combustion process for externally controlled reciprocating piston

Growing community of inventors

Deizisau, Germany

Klaus Binder