Abstract: An arrangement is proposed for forming a piezoelectric actuator, which has at least one piezoelectric element that in each case consists of a multi-layer structure of piezoelectric-layers, wherein internal electrodes arranged between the piezoelectric-layers in the direction of the build-up of the layers of the piezoelectric element, have an electrical voltage of different polarity alternately applied to them. Around the piezoelectric element, or in the case of multiple piezoelectric elements positioned in series in the activation direction, around the piezoelectric elements, and at least partially around the actuator head and the actuator foot there is arranged a covering system made from at least one layer of an insulating material. The at least one layer encloses the joints between the piezoelectric element or elements and the actuator head and the actuator foot, forming a seal.

Abstract: A fuel injection device of an internal combustion engine includes a piezoelectric actuator and a valve element that are coupled to one another. The valve element has a pressure stage. An increase in the force acting on the piezoelectric actuator is interpreted as an actual opening of the valve element, and/or a decrease in the force acting on the piezoelectric actuator is interpreted as an actual closing of the valve element, and that these be taken into account at least part of the time in the controlling of the piezoelectric actuator.

Abstract: A fuel injection valve with a valve member axially displaceable in a bore of a valve body comprises a valve stem, the combustion chamber end, with which it interacts with a valve face of the valve body, at least one injection opening downstream of the valve face and opening into the combustion chamber to be supplied with fuel, a guide section of the valve body guiding the valve member and being disposed axially between an annular gap connected to the high-pressure fuel line and an annular space leading to the valve face, a first throttle connection permanently interlinking the annular gap and the annular space, and a second throttle connection interlinking the annular gap and the annular space as of a defined opening stroke of the valve member and having a smaller throttle resistance than the first throttle connection. The guide section is configured by a guide sleeve that is fastened at the combustion chamber end of the valve body in the bore so as to be stationary.

Abstract: A fuel injection system for an internal combustion engine is proposed. The fuel injection system has a high pressure part and a low pressure part. In the high pressure part, fuel is fed from at least one high pressure accumulator/reservoir to at least one fuel injector. In the low pressure part, the at least one fuel injector is connected to at least one low pressure accumulator/reservoir, wherein a pressure is maintained in the at least one low pressure accumulator by at least one pressure holding valve. Furthermore, the fuel injection system has at least one device for the after-treatment of exhaust gases of the internal combustion engine in an exhaust gas section. Furthermore, the fuel injection system has at least one metering device for the metered introduction of fuel into the exhaust gas section. Said at least one metering device is connected hydraulically to the at least one low pressure accumulator.

Abstract: A fuel injection device of an internal combustion engine includes a piezoelectric actuator and a valve element that are coupled to one another. The valve element has a pressure stage. An increase in the force acting on the piezoelectric actuator is interpreted as an actual opening of the valve element, and/or a decrease in the force acting on the piezoelectric actuator is interpreted as an actual closing of the valve element, and that these be taken into account at least part of the time in the controlling of the piezoelectric actuator.

Abstract: A common rail fuel system essentially comprising at least one rail, at least two injectors, and a respective supply line of a definite length between the rail and each injector. In order to prevent oscillation-generated movements of one supply line from being transmitted to the adjacent supply lines, the respective adjacent supply lines are embodied with different natural frequencies as a result of the supply lines of a rail being of different dimensions, for example different lengths.

Abstract: The invention relates to an injection nozzle for an internal combustion engine having a nozzle needle or needle unit for controlling an injection of fuel through at least one injection orifice and an actuator for driving a coupling piston. The nozzle needle or needle unit has a control surface that at least partially delimits a control chamber which communicates with a coupling chamber that is at least partially delimited by the coupling piston. The control surface is situated at the end of the nozzle needle or nozzle unit oriented away from the at least one injection orifice and the actuator drives the coupling piston to open the nozzle needle in such a way that a volume of the coupling chamber increases.

Abstract: A fuel injector with a direct needle control for an internal combustion engine, having an actuator, a hydraulic booster, and a nozzle needle guided in a nozzle body and acting on a nozzle needle sealing seat. The hydraulic booster includes a booster piston connected to the actuator and a nozzle needle booster piston connected to the nozzle needle; a booster chamber in the form of an actuator coupler chamber is associated with a pressure surface of the actuator booster piston; and depending on the pressure in the actuator coupler chamber, the nozzle needle is lifted away from the nozzle needle sealing seat, thus initiating an injection. In addition to the actuator booster piston, a control element is provided that is able to execute a stroke motion, is hydraulically coupled to the actuator coupler chamber by means of a first control surface, and is associated with a control chamber by means of a second control surface.

Abstract: The invention relates to a valve for a fuel injection system, having a valve seat embodied in a valve housing, and having a valve member which is movable in the valve housing and has a sealing face that when the valve is closed rests sealingly against the valve seat and when the valve is open, together with the valve seat, defines a valve gap through which fuel flows. To prevent cavitation damage, the valve member has an encompassing hollow throat, which is disposed in the flow direction immediately downstream of the sealing face and is adjoined by an encompassing cross-sectional thickening of the valve member.

Abstract: A fuel injection system for internal combustion engines, including a high-pressure part and a low-pressure part. In the high-pressure part, fuel is delivered to a high-pressure reservoir via a high-pressure pump and a high-pressure line. Injectors are supplied from the high-pressure reservoir. In the low-pressure part, the injectors communicate with a low-pressure reservoir where a pressure of ?50 bar is maintained by a pressure holding valve. At a pressure in the low-pressure reservoir above the opening pressure of the pressure holding valve, the fuel is returned to the fuel container via a return line. The low-pressure reservoir communicates with the high-pressure line of the high-pressure part via an overflow valve and an overflow line.

Abstract: A fuel injector with a direct needle control for an internal combustion engine, having an actuator, a hydraulic booster, and a nozzle needle guided in a nozzle body and acting on a nozzle needle sealing seat. The hydraulic booster includes a booster piston connected to the actuator and a nozzle needle booster piston connected to the nozzle needle; a booster chamber in the form of an actuator coupler chamber is associated with a pressure surface of the actuator booster piston; and depending on the pressure in the actuator coupler chamber, the nozzle needle is lifted away from the nozzle needle sealing seat, thus initiating an injection. In addition to the actuator booster piston, a control element is provided that is able to execute a stroke motion, is hydraulically coupled to the actuator coupler chamber by means of a first control surface, and is associated with a control chamber by means of a second control surface.

Abstract: The invention relates to a common rail injector for injecting fuel in a common rail injection system of an internal combustion engine, having an injector housing, which communicates with a central high-pressure reservoir and in which a nozzle needle is axially displaceable in order to adjust the injection as a function of the pressure in a control chamber, and having a sealing element, which is disposed in an annular chamber that is provided between a valve element and the injector housing. In addition to the sealing element, a support device is disposed in the annular chamber between the valve element and the injector housing.

Abstract: The present invention is directed to a solenoid valve for controlling a fuel injector in an internal combustion engine, having an electromagnet, an armature having an armature pin which is movably supported with respect to the electromagnet, and an armature plate supported on the armature pin in a manner allowing sliding movement, and a control-valve member moved together with the armature and cooperating with a valve seat to open and close a fuel discharge passage, the armature plate, in response to the control-valve member striking the valve seat during the closing of the solenoid valve, being able to be moved, under the influence of its own inert mass, along the armature pin along an overtravel distance, from a stop secured to the armature pin up to a stationary overtravel stop.

Abstract: A fuel injection valve for internal combustion engines having a valve body in which a bore is embodied, a valve seat face, at least one injection opening embodied on the end toward the combustion chamber of the bore, and at least one injection opening connecting the bore with the combustion chamber of the engine. A nozzle needle is longitudinally displaceably guided in the bore and on its end toward the combustion chamber it has a sealing face, which cooperates with the valve seat face and thus controls the at least one injection opening. The nozzle needle has a central longitudinal bore, in which an inner needle is disposed that is fixed immovably relative to the valve body. The nozzle needle is guided over at least part of its length on the inner needle, so that the nozzle needle is kept exactly centrally in the bore at all times.

Abstract: The invention relates to a common rail injector for injecting fuel in a common rail injection system of an internal combustion engine, having an injector housing which communicates with a central high-pressure reservoir and in which a nozzle needle that cooperates with a valve piston which is guided in a valve piece is axially displaceable. To increase the service life of the injector, the end toward the nozzle needle of the valve piston or of a thrust rod triggered by the valve piston is guided coaxially to the axis of symmetry of the nozzle needle.

Abstract: A solenoid valve for controlling a fuel injector of an internal combustion engine, including an electromagnet, a movable armature featuring an armature plate and an armature pin, as well as a control valve member, which is moved with the armature and cooperates with a valve seat, for opening and closing a fuel discharge passage of a control pressure chamber of the fuel injector, the armature plate being supported on the armature pin, so that it is slidably movable in the closing direction of the control valve member under the action of its inertial mass, against the elastic force of a return spring that acts upon the armature plate; and including a hydraulic damping device which permits damping of a post-oscillation of the armature plate during its dynamic sliding on the armature pin.

Abstract: The present invention relates to a solenoid valve for controlling a fuel injector of an internal combustion engine, including an electromagnet (29), a movable armature featuring an armature plate (28) and an armature pin (27), as well as a control valve member (25) which is moved with the armature and cooperates with a valve seat (24), for opening and closing a fuel discharge passage (17) of a control pressure chamber (14) of the fuel injector (1), the armature plate (28) being supported on the armature pin (27) in such a manner that it is slidably movable in the closing direction of the control valve member (25) under the action of its inertial mass, against the elastic force of a return spring (35) that acts upon the armature plate (28); and including a hydraulic damping device which permits damping of a post-oscillation of the armature plate (28) during its dynamic sliding on the armature pin (27).

Abstract: The present invention is directed to a solenoid valve for controlling a fuel injector in an internal combustion engine, having an electromagnet, an armature having an armature pin which is movably supported with respect to the electromagnet, and an armature plate supported on the armature pin in a manner allowing sliding movement, and a control-valve member moved together with the armature and cooperating with a valve seat to open and close a fuel discharge passage, the armature plate, in response to the control-valve member striking the valve seat during the closing of the solenoid valve, being able to be moved, under the influence of its own inert mass, along the armature pin along an overtravel distance, from a stop secured to the armature pin up to a stationary overtravel stop.

Abstract: A fuel injection valve for internal combustion engines, having a valve body (3) in which a bore (7) is embodied. A valve seat face (10) and at least one injection opening (9) are embodied on the end toward the combustion chamber of the bore (7), and at least one injection opening (9) connects the bore (7) with the combustion chamber of the engine. A nozzle needle (12) is longitudinally displaceably guided in the bore (7) and on its end toward the combustion chamber it has a sealing face (217), which cooperates with the valve seat face (10) and thus controls the at least one injection opening (9). The nozzle needle (12) has a central longitudinal bore (19), in which an inner needle (14) is disposed that is fixed immovably relative to the valve body (3). The nozzle needle (12) is guided over at least part of its length on the inner needle (14), so that the nozzle needle (12) is kept exactly centrally in the bore (7) at all times (FIG. 1).

Abstract: A solenoid valve for controlling a fuel injector of an internal combustion engine, including an electromagnet 29, a displaceable armature having an armature plate 28 and an armature pin 27, and a control valve element 25 which is displaced with the armature and which cooperates with a valve seat 24 for opening and closing a fuel discharge channel 17 of a control pressure chamber 14 of the fuel injector 1. The armature plate 28 is mounted on the armature pin 27 so as to be slidably displaceable in opposition to the tensioning force of a restoring spring 35 acting on the armature plate 28 under the influence of the inert mass of the armature plate in the closing direction of the control valve element 25, and is pressed by the restoring spring 35 in its rest state against a stop part 26 attached to the armature pin 27. The stop part 26 is designed to encircle the periphery of the armature pin 27 by more than 180° in a plane perpendicular to the direction of movement of the armature pin.