Robert Boschgmbh

Sebastian Kanne

Peter Boehland

Godehard Nentwig

Walter Egler

Hans-Christoph Magel

Uwe Gordon

Achim Brenk

Manfred Mack

Wolfgang Klenk

Michael Offenhuber

Werner Teschner

Michael Bauer

Hansjoerg Egeler

Giovanni Ferraro

Stefan Lorengel

Markus Jungemann

Rainer Keck

Ingolf Kahleyss

The invention relates to a method for identifying a blockage of one or more spray openings of a dosing valve of an SCR catalytic converter system. Said method comprises the closure of the dosing valve, the determination of a first pressure profile in the hydraulic system in the delivery module of the SCR catalytic converter system, and the determination of the stiffness of the hydraulic system from the first pressure profile. The dosing valve is subsequently opened, a second pressure profile in the hydraulic system in the delivery module of the SCR catalytic converter system is determined, and a blockage of one or more spray openings of the dosing valve is determined from the stiffness and from the second pressure profile.

Method for identifying a blockage of a dosing valve of an SCR catalytic converter system

A fuel injector having a piezoelectric actuator in an injector body and held in contact with the injector body on one side and with a sleevelike booster piston on the other via first spring means. A nozzle body joined to the injector body and a stepped nozzle needle is guided in the body. A second spring disposed inside the booster piston which together with the injection pressure acting on the back side of the nozzle needle keeps the nozzle needle in the closing position. A control chamber on the end toward the nozzle needle of the booster piston communicates, via at least one leakage gap with a fuel supply at injection pressure, and the nozzle needle is urged in the opening direction by the fuel located in the control chamber. The booster piston actuated by the piezoelectric actuator is spatially associated directly with the nozzle needle so that the nozzle needle is fitted, with a rear region that has a larger diameter than a region of the nozzle needle toward the nozzle outlet, into the inner chamber of the booster piston.

Injector for fuel injection systems of internal combustion engines, especially direct-injection diesel engines

A fuel injection device for an internal combustion engine, having two valve elements each having a hydraulic control surface acting in the closing direction and associated with a hydraulic control chamber. A control valve influences the pressure in the control chamber, and loading devices act on the valve elements in the opening direction. The valve elements react at different hydraulic opening pressures prevailing in the control chamber. The control valve is able to set at least three different pressure levels in the control chamber: all of the valve elements are closed at a comparatively high pressure level; one valve element is open at a medium pressure level; and all of the valve elements are open at a comparatively low pressure level.

Fuel injection device for an internal combustion engine

A method for controlling an injection system of an internal combustion engine having at least one injector, the fuel metering being divided into a first partial injection and at least one second partial injection, and a control signal which determines the fuel quantity to be injected with the aid of the at least one injector being corrected as a function of a pressure wave influencing the at least two partial injections, the pressure wave correction being performed on the basis of a periodic model which models the quantity wave as a sum of periodic functions.

Method for controlling an injection system of an internal combustion engine

A fuel injection valve for internal combustion engines, having a housing () in which a pistonlike valve member () is disposed longitudinally displaceably in a bore (). The valve member () is surrounded, over at least part of its length, by a pressure chamber (), embodied in the housing (), that can be filled with fuel at high pressure; the valve member () controls the communication of the pressure chamber () with at least one injection opening (). The pressure chamber () communicates with a damping chamber (), embodied in the housing (), via at least one throttle () disposed in the housing (), so that pressure fluctuations that occur in the damping chamber () rapidly fade (FIG.).

Fuel injection valve for internal combustion engines with damping chamber reducing pressure oscillations

A fuel injection system with a fuel injection valve and a control valve, which control valve has a control valve member that can move longitudinally in a control valve bore. The control valve member is provided with a control valve sealing surface, which cooperates with a control valve seat and thereby controls the connection between a first pressure chamber and a second pressure chamber, where the first pressure chamber is connected to a high-pressure accumulation chamber. A bore is embodied in a valve body and contains a piston-shaped valve needle whose end oriented toward the combustion chamber controls the opening of at least one injection opening by virtue of the fact that it executes a longitudinal movement due to the impingement of the pressure in a pressure chamber; the pressure chamber is connected to the second pressure chamber by means of a supply conduit. The first pressure chamber is connected by means of a throttle to a damping chamber that is otherwise closed, as a result of which, pressure oscillations that are produced by the closing of the control valve are rapidly damped.

Fuel injection system for internal combustion engines

A fuel injection system for an internal combustion engine with direct injection includes a fuel injection device which can inject the fuel directly into a combustion chamber of the engine has a valve element bordering on a work chamber, and the position of the valve element depends on the pressure in the work chamber. A pressure booster piston borders on a control chamber on one side and on a high-pressure chamber on the other. A fuel supply can subject the control chamber to various pressures. The pressure booster piston is integrated with the fuel injection device and that the high-pressure chamber is integrated with the work chamber.

Fuel injection system for direct injection internal combustion engine

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.

A fuel injection valve includes a housing in which a pistonlike valve member is disposed longitudinally displaceably in a bore to cause at least one injection opening to communicate with a pressure chamber embodied in the housing. An inlet conduit discharges into the pressure chamber to fill the pressure chamber with fuel at high pressure. A fuel-filled control chamber in the housing at least indirectly exerts a force acting in the closing direction on the valve member. The control chamber communicates with the inlet conduit and can be made to communicate via a control valve with a leak fuel chamber. A damping chamber communicates with the inlet conduit via a throttle.

Growing community of inventors

Schwaikheim, Germany

Sebastian Kanne