Robert Boschgmbh

Wolfgang Klenk

Uwe Gordon

Achim Brenk

Manfred Mack

Andreas Pfaeffle

Stefan Scherer

Nestor Rodriguez-Amaya

Peter Boehland

Detlev Potz

Thomas Kuegler

Walter Egler

Hubert Greif

Frank Schweizer

Werner Teschner

Sebastian Kanne

Matthias Burger

Andreas Wagner

Hansjoerg Egeler

Giovanni Ferraro

Gerhard Mack

Roland Bleher

Andreas Schaffrath

Ulrich Meingast

Tobias Hoeffken

Simone Neuberth

Ulf-Peter Schmeling

Wilhelm Dueck

Ruben Schreiber

Reinold Weinmann

Albrecht Schwaderer

Bernhard Kurrle

Georgios Lolas

Ingolf Kahleyss

Guido Stammsen

Felix Birkhold

Max Leonhard

Armin Strauch

A method for verifying the plausibility of a measuring device for determining a quality of an aqueous urea solution in a reservoir of an SCR catalyst system comprises determining whether a filling of the reservoir has taken place, determining the quality of the aqueous urea solution in the reservoir and detecting whether an error of the measuring device is present or whether the reservoir was filled with an aqueous urea solution, the quality of which deviates from a default value consisting of a filling status of the reservoir and the quality of the aqueous urea solution in said reservoir.

Method for verifying the plausibility of a measuring device for determining the quality of an aqueous urea solution in a reservoir of an SCR catalyst system

The invention provides for a method for operating an SCR catalytic converter for the aftertreatment of exhaust gases of an internal combustion engine, wherein a reducing agent tank () with reducing agent and a reducing agent metering device () are provided. The reducing agent tank () has at least one tank heater () having PTC characteristics. A variable characterizing the heater current is acquired for detecting cavities () in the reducing agent tank () when the reducing agent is frozen. The presence of cavities is suggested from a deviation of the acquired value or values for the variable characterizing the heater current from a predeterminable reference value, which represents a reducing agent tank without cavities.

Method for operating an SCR-catalytic converter

A procedure is introduced to operate a diesel engine, which has a catalytic converter with three-way conversion characteristics. The procedure is characterized thereby, in that if the engine rotational speed increases without in the process exceeding an engine rotational speed threshold value and the engine's load is greater than a load threshold value, the diesel engine is operated in such a manner that the diesel engine alternately generates an oxidizing and a reductive exhaust gas atmosphere before the catalytic converter. Additionally a control unit is introduced, which controls the sequence of the procedure.

Procedure and control unit to operate a diesel engine

A method is described for operating an internal combustion engine, in particular of a motor vehicle. In the method, a lean air/fuel mixture is burned in a combustion chamber; nitrogen oxides contained in the exhaust gas are stored in an accumulator-type catalytic converter; a storage efficiency, with which the accumulator-type catalytic converter stores the nitrogen oxides contained in the exhaust gas, is ascertained; and the storage efficiency is ascertained as a function of an instantaneous space velocity of the exhaust gases in the accumulator-type catalytic converter. Two efficiencies are ascertained at least as a function of the temperature of the accumulator-type catalytic converter and a space velocity. One of the two efficiencies is ascertained for a great space velocity, and the other efficiency is ascertained for a small space velocity. The storage efficiency is ascertained as a function of the instantaneous space velocity from the two efficiencies.

Method for operating an internal combustion engine

The invention relates to a 3/2-port directional-control valve for controlling the injection of fuel in a common rail injection system of an internal combustion engine, with a first switched position in which an injection nozzle is connected to a fuel return and with a second switched position in which the injection nozzle is connected to a high-pressure fuel reservoir. The beginning of the injection takes place in a pressure-controlled manner, whereas the end of the injection takes place in a stroke-controlled manner.

3/2 Directional-control valve

The invention relates to a 3/2-way valve for controlling the injection of fuel in a common rail injection system of an internal combustion engine, having a first switching position, in which an injection nozzle is in communication with a fuel return, and a second switching position, in which the injection nozzle is in communication with a common rail. To improve the function and quality of the injection, the 3/2-way valve includes two force-balanced control pistons, which are guided separately from one another, and on each of which a respective valve seat edge is embodied.

3/2-way valve

The invention relates to a 3/2-way valve for controlling the injection of fuel in a common rail injection system of an internal combustion engine, having a first switching position, in which an injection nozzle is in communication with a fuel return, and having a second switching position, in which the injection nozzle is in communication with a high-pressure fuel reservoir. To improve the function and quality of the injection, the 3/2-way valve includes a force-balanced control piston, and the control edge of the control piston is pressure-equalized by means of a blind bore.

Seat/slide valve with pressure-equalizing pin

In a fuel injection nozzle having a nozzle body which body has one first and one second group of injection ports, one first and one second nozzle needle, and one separate pressure chamber for each nozzle needle, so that the injection needles are adjustable independently of one another between a closed position, in which the injection ports associated with the corresponding nozzle needle are closed, and an injection position, in which the corresponding injection ports are opened, a free choice of injection cross sections is to be made possible, while the design is simple. To that end, it is provided that the two nozzle needles adjoin one another.

Injection nozzle

A control valve and a fuel injection valve provided with same should be produced, in which it is possible to switch from a first operating state to a second operating state inexpensively and with short switching times, without requiring a hydraulic control line. To this end, a control valve is provided, which has a valve housing, a pressure chamber filled with electrorheological fluid, a displacing element that can slide in the valve housing and protrudes into the pressure chamber, and two electrodes that can apply an electrical field to the electrorheological fluid.

Control valve and fuel injection valve provided with same

A fuel injection system, having a fuel injection valve and a control valve, which control valve has a control valve member that is longitudinally displaceable in a control valve bore. A control valve sealing face is embodied on the control valve member; it cooperates with a control valve seat and thus controls the communication between a first pressure space and a second pressure space; the first pressure space communicates with a high-pressure collection chamber. In a valve body, a bore is embodied in which a pistonlike valve needle, with its end toward the combustion chamber, controls the opening of at least one injection opening by executing a longitudinal motion in response to the pressure in a pressure chamber; the pressure chamber communicates with the second pressure space via an inlet conduit. The first pressure space communicates via a throttle with a damping chamber, embodied as a blind bore and otherwise closed off, as a result of which pressure fluctuations that occur upon closure of the control valve are rapidly damped.

Fuel injection system for internal combustion engines

In an injection nozzle for a fuel injection system, the opening stroke of the nozzle needle is to be limited selectively, so that different injection cross sections can be employed. To that end, the injection nozzle is provided with a nozzle body, a nozzle needle displaceable in the nozzle body, two groups of injection ports, which are uncovered as a function of an opening stroke of the nozzle needle, a piston that is connected to the nozzle needle, a stop chamber in which the piston is disposed and which is provided with an outlet, and a control valve that can open and close the outlet of the stop chamber, as a result of which the stroke of the piston in the stop chamber and thus the opening stroke of the nozzle needle can be selectively limited.

In a fuel injection system for internal combustion engines, including an electronically triggered control valve with an axial through bore, which is divided by two valve seats into three annular chambers, to which respectively a supply line for fuel at high pressure, a high-pressure line leading away to an injection valve, and a relief line are connected, and having a control piston, which is guided in the through bore and which has two valve sealing faces cooperating with the two valve seats, respectively, the control piston according to the invention has a further valve sealing face, which cooperates with the first valve seat and whose spacing from the first valve sealing face is at least equal to the spacing between the second valve sealing face and the second valve seat when the first sealing seat is closed. A communication between the supply line and the relief line is thus reliably prevented.

Fuel injection device for internal combustion engines

Growing community of inventors

Loechgau, Germany

Wolfgang Klenk