Abstract: The invention relates to a fuel injector for injecting fuel into a combustion chamber of an internal combustion engine. A fuel supply line enters an injector housing from a high pressure fuel source which can be hydraulically connected to a pressure chamber. A 3/2 directional control valve for injecting fuel into the combustion chamber has a valve piston which can be moved axially back and forth between a rest position and an injection position. The 3/2 directional control valve, by a first end face of the valve piston, which adjoins a hydraulic coupling chamber, is hydraulically coupled to and can be activated by a piezoelectric actuator. The 3/2 directional control has a ball element which is connected to a second end face of the valve piston and, in the rest position, can be moved against a first sealing edge and, in the injection position, can be moved against a second sealing edge.

Abstract: A leak-free injector is proposed, the closing force of which is increased by a closing piston. An injector has a nozzle needle and a control valve, the nozzle needle being guided in an injector housing and cooperating with a nozzle needle seat of the injector housing. A high-pressure chamber is present between the control valve and the nozzle needle seat, and the closing piston is provided on the nozzle needle. The closing piston subdivides the high-pressure chamber into a first region and a second region. The two regions of the high-pressure chamber communicate hydraulically via a closing throttle restriction.

Abstract: The invention relates to a fuel injector with an injector housing (6) comprising a pressure chamber (15), from which, depending on the pressure in a control chamber (22), pressurized fuel is injected into a combustion chamber of an internal combustion engine when the pressure in the control chamber (22) with the aid of a control valve device (12) is reduced so far, that a nozzle needle (10) opens. In order to present a fuel injector, constructed in a simple and cost efficient way, the pressure chamber (15) is sealed at an end away from the combustion chamber with a valve piece (30) having a sealing face or sealing edge facing away from the combustion chamber and lying against the injector housing (6).

Abstract: The invention relates to a fuel injector having an injector housing which has a high-pressure fuel connection which is connected outside the injector housing to a central high-pressure fuel source and inside the injector housing to a pressure space. From the fuel injector highly pressurized fuel is injected into a combustion chamber of an internal combustion engine as a function of the pressure in a control space when a nozzle needle opens In order to provide a fuel injector which can be manufactured inexpensively, the pressure in the control space is controlled directly by a magnetic actuator.

Abstract: The invention relates to a fuel injection device with a multi-part injector body containing a pressure booster that can be actuated by means of a differential pressure chamber, and includes a pressure booster piston that seals a working chamber off from the differential pressure chamber. An on-off valve disposed above the injector body can actuate the fuel injection device. A pressure change in the differential pressure chamber occurs via a central control line that extends through the pressure booster piston of the pressure booster.

Abstract: A fuel injection system for internal combustion engines, having a fuel injection nozzle supplied with fuel by a high-pressure fuel source, which fuel injection nozzle has a movable nozzle piston for opening and closing injection openings, an injection nozzle high-pressure chamber, and an injection nozzle control chamber. A pressure boosting device connected between the fuel injection nozzle and the high-pressure fuel source has a movable piston, a work chamber, and a high-pressure chamber, in which a filling connection which is open for filling the high-pressure chamber when the fuel injection nozzle is closed and is itself closed when the fuel injection nozzle is open.

Abstract: The invention relates to a fuel injector having an injector housing containing a pressure chamber from which highly pressurized fuel is injected into a combustion chamber of an internal combustion engine. A nozzle needle control chamber is provided in the housing such that a nozzle needle has its first end disposed in the nozzle needle control chamber. A second end of the nozzle needle lifts away from its seat as a function of the pressure in the nozzle needle control chamber. The pressure in the nozzle needle control chamber is controlled by a switching valve device which is equipped with a piezoelectric actuator that expands longitudinally when supplied with current. A valve piston is coupled to the piezoelectric actuator and has its free end of the disposed in a valve piston control chamber. The valve piston control chamber communicates with the nozzle needle control chamber.

Abstract: Disclosed is a fuel injection device comprising a housing and a valve element disposed therein and cooperating with a valve seat located in the area of at least one fuel discharge port. The valve element is composed of several parts while at least two parts of the valve element are coupled to each other via a hydraulic coupler.

Abstract: A common rail injector having an injector housing having a fuel supply line which communicates with a central high-pressure fuel source outside the injector housing and with a pressure chamber inside the injector housing, from which pressure chamber, as a function of the position of a 3/2-way control valve, fuel subjected to high pressure is injected. The 3/2 way control valve, includes a valve piston, movable back and forth in the injector housing between a position of repose and an injection position, which piston is coupled hydraulically with a piezoelectric actuator that is subjected to the pressure from the high-pressure fuel source.

Abstract: An apparatus for injecting fuel into an internal combustion engine having a fuel injector acted on with highly pressurized fuel actuated by means of a metering valve device that is able to control the pressure in a pressure booster control chamber so that in a pressure booster pressure chamber delimited by a pressure booster piston which can be filled via a check valve with high-pressure fuel and communicates with an injection valve member pressure chamber, the pressure booster piston increases the pressure, causing an injection valve member for injecting fuel to open.

Abstract: A fuel injector is supplied with fuel under pressure via a high-pressure source and has direct control of an injection valve member by a piezoelectric actuator via a hydraulic booster. The injection valve member of the fuel injector furthermore has a double seat and the injection valve member is provided with two sealing seats which subdivide a nozzle chamber of the fuel injector into three subchambers. When the injection valve member is closed, a first subchamber and a third are in fluidic communication with one another and are supplied with fuel. The second subchamber, which is in communication with injection openings, is conversely fluidically decoupled from the subchambers by the sealing seats. This proposed disposition, with a combination of direct needle control and a double seat of the injection valve member has the advantage that unthrottling of the fuel injector occurs at a very short injection valve member stroke. As a result, even short piezoelectric actuators can in particular be used.

Abstract: A fuel injector for injecting fuel into a combustion chamber of an internal combustion engine, including a pressure booster, whose booster piston separates a work chamber, subjected to fuel via a pressure reservoir, from a pressure-relievable differential pressure chamber. A pressure change in the differential pressure chamber is effected via an actuation of a servo valve, which opens or closes a hydraulic connection of the differential pressure chamber to a first low-pressure-side return. The servo valve has a piston guided between a control chamber and a first hydraulic chamber. On this servo valve piston, a hydraulic face that positions the servo valve piston constantly in the opening direction when system pressure is applied and a first sealing seat that closes or opens a low-pressure-side return are embodied.

Abstract: A fuel injector with a pressure booster supplied with fuel at high pressure. A work chamber of the pressure booster is separated from a differential pressure chamber via a booster piston. The pressure relief and the subjection to pressure of the differential pressure chamber are effected via a switching valve which communicates with the differential pressure chamber via a control line. A pressure chamber on an injection valve member communicates with a compression chamber of the pressure booster via a pressure chamber supply line. The switching valve is embodied as a direct-switching 3/2-way valve, whose valve needle is pressure-balanced and has both a sliding seat and a slide seal.

Abstract: A fuel injector for injecting fuel that is at high pressure into a combustion chamber of an internal combustion engine has an injection valve member triggered by an actuator and a coupler chamber; the actuator acts on the injection valve member and the injection valve member opens or closes at least one injection opening. The coupler chamber is located on the side of the actuator diametrically opposite the injection valve member; and the coupler chamber is filled with fuel that is at system pressure when the injection opening is closed.

Abstract: A servo valve for actuating a pressure booster of a fuel injector, the pressure booster having a work chamber separated by a booster piston from a differential pressure chamber and the pressure change in the differential pressure chamber of the pressure booster is effected via the servo valve, via switching valve. The control chamber of the servo valve can both be made to communicate with a high-pressure source and pressure-relieved into a low-pressure-side return, and for generating a fast closing motion at the valve piston, a pressure shoulder acting in the closing direction of the valve piston is embodied between the control chamber and the hydraulic chamber, and control edges without a common opening phase are embodied on the valve piston.

Abstract: A common rail injector having an injector housing having a fuel supply line which communicates with a central high-pressure fuel source outside the injector housing and with a pressure chamber inside the injector housing, from which pressure chamber, as a function of the position of a 3/2-way control valve, fuel subjected to high pressure is injected. The 3/2 way control valve, includes a valve piston, movable back and forth in the injector housing between a position of repose and an injection position, which piston is coupled hydraulically with a piezoelectric actuator that is subjected to the pressure from the high-pressure fuel source.

Abstract: The invention relates to a device for injecting fuel into a combustion chamber of an internal combustion engine, and which includes a fuel injector which can be acted upon by fuel at high pressure via a high-pressure source and is actuatable via a metering valve. Associated with the injection valve member is a damping element, which is movable independently of it and defines a damping chamber. The damping element has at least one overflow conduit for connecting the damping chamber to a further hydraulic chamber.

Abstract: A fuel injection system of an internal combustion engine has, depending on the number of cylinders, at least one local pump element, assigned to each injector, of a unit fuel injector or a pump-line-nozzle system for compressing the fuel. The injector and/or the supply line to the injector form a local pressure reservoir chamber.

Abstract: 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.

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.