Abstract: In a pressure-controlled fuel injection system, a nozzle needle is subjected to pressure in the closing direction by a nozzle spring. A nozzle chamber for opening the nozzle needle is connectable to a pressure reservoir via a pressure line. A hydraulic device is embodied to reinforce the closing performance of the nozzle needle. As a result, a faster closing performance of the nozzle needle is achieved.

Abstract: A fuel injection system (1) for internal combustion engines has at least one stroke-controlled injector (10). A pressure booster (9) that has a movable piston (26) is connected between the at least one injector (10) and a high-pressure working medium source (5). The movable piston (26) divides a primary chamber (13), which can be connected to the high-pressure working medium source (5), from a pressure chamber (8) that communicates with the at least one injector (10) and is filled with fuel. The pressure booster (9) generates a first fuel system pressure in the injector (10), which is used for the injection. The fuel injection system (1) has means for furnishing a further, second fuel system pressure, and these means can be used for injection without activating the pressure booster (10).

Abstract: The present invention relates to an injection device having an injection valve (12), a valve device (18, 20) for controlling the injection, and a setting element (22) for operating the valve device (18, 20), the valve device having at least one first valve (18) and a second valve (20) which can be operated by the settling element (22) via a common hydraulic coupling space (24). The present invention further relates to a method for injecting fluid in which a setting element is (22) is activated, a valve device (18, 20) is operated by the setting element (22), and an injection valve (12) is opened, the first valve (18) and a second valve (20) of the valve device (18, 20) being operated by the setting element (22) via a common hydraulic coupling space.

Abstract: In a fuel injection system for an internal combustion engine, in which the fuel pumped by means of a high-pressure pump can be injected into the combustion chamber of the engine at at least two different, high fuel pressure via injectors, between the high-pressure pump and the injectors, at least one central pressure booster unit for all the injectors is provided. The pressure booster unit is triggerable in a targeted way as need, and as a result the fuel which is at the higher pressure can be better regulated in quantity, and the losses from friction can be reduced accordingly as well.

Abstract: An injection device with an injection nozzle (42), a pressure intensifier (12) for intensifying a primary pressure, a first valve device (32) for triggering the pressure intensifier (12), and an actuator for actuating the first valve device (32), wherein the pressure intensifier (12) is activated in a first state of the first valve device (32), the pressure intensifier (12) is deactivated in a second state of the first valve device (32), and a limitation of the through flow quantity to the injection nozzle (42) is provided. The invention also relates to a method, which makes advantageous use of the device according to the invention.

Abstract: The invention relates to an injection device with an injector (12), a pressure intensifier (16) for intensifying a primary pressure, a valve device (18, 20) for actuating the pressure intensifier (16), and an actuating element (22) for actuating the valve device (18, 20), wherein the valve device has at least one first 2/2-port directional-control valve (18) and one second 2/2-port directional-control valve (20), which can be actuated by the actuating element (22). The invention also relates to a method for injecting fluid, in which an actuating element (22) is activated, the actuating element (22) actuates a valve device (18, 20), the valve device (18, 20) actuates a pressure intensifier (16) for intensifying a primary pressure, and an injector (12) is opened, wherein the actuating element (22) actuates a first 2/2-port directional-control valve (18) and a second 2/2-port directional-control valve (20) of the valve device.

Abstract: A method and system for injecting fuel in at least two different high fuel pressures via injectors into a combustion chamber of an internal combustion engine. The higher fuel pressure being stored in a central pressure reservoir, the lower fuel pressure is generated individually locally for each injector, at all times during the injection event by diversion of the higher fuel pressure. The diversion being activatable or deactivatable via a multi-way valve. To that end, a corresponding fuel injection system with a central pressure reservoir for storing the higher fuel pressure has a local diversion unit for each injector by means of which the lower fuel pressure can be generated dissipatively from the higher fuel pressure, and the local diversion unit has a multi-way valve for activating and deactivating the diversion, respectively. In this way, an improved metering of the lower fuel pressure can be achieved.

Abstract: A fuel injection system includes a pressure storage chamber and one injector assigned to each cylinder, which injector can be connected to the pressure storage chamber via a pressure line that includes a metering valve. Using a single 2/2-way valve as a metering valve per cylinder makes for a more-economical manufacture of a fuel system, especially for small engines. The fuel injection is done under pressure control.

Abstract: In a fuel injection system for an internal combustion engine, in which fuel can be injected at least two different, high fuel pressures, via injectors, into the combustion chamber of the engine, having a central first pressure reservoir for the higher fuel pressure and a central second pressure reservoir, supplied from the first pressure reservoir, in which by regulation of its fuel delivery, the lower fuel pressure is maintained, and having a valve unit for switchover between the higher and the lower fuel, the valve unit for switchover between the higher and the lower fuel is provided locally for each injector. With this injection system, improved metering of the lower fuel pressure is possible.

Abstract: A fuel injection system has a pressure booster unit (1), disposed between a pressure reservoir chamber and a nozzle chamber, which unit has a displaceable piston unit (4) for boosting the pressure of the fuel to be supplied to the nozzle chamber. For controlling the pressure booster unit (1), the piston unit (4) has a transition from a larger to a smaller piston cross section and a differential chamber (2) formed thereby, which is connected to the pressure reservoir chamber via a filling path (13) having a filling valve (10). A reduction in the control quantity during the triggering of the pressure booster unit (1) and the performance of a rapid restoration of the piston unit (4) are attained.

Abstract: A fuel injection system has one or more unit fuel injectors or pump-line-nozzle system, corresponding in number to the number of cylinders, for compressing the fuel and a hydraulic pressure booster unit. With the aid of the unit fuel injector and the pressure booster unit, a fuel injection can be performed with great precision over a wide rpm range.

Abstract: The invention relates to a metering valve for controlling the delivery of fuel from a high-pressure fuel line (1) to an injection nozzle (6) of an internal combustion engine, having one connection for the high-pressure fuel line (2), one connection for the injection nozzle (6), and one connection for a leak fuel line (13).

Abstract: A fuel injection system having at least two different, high system pressures for an internal combustion engine, includes a first central pressure reservoir for the lower system pressure and includes a second central pressure reservoir, supplied from a high-pressure pump, for the higher system pressure, both pressure reservoirs being connectable by line to the injector of each cylinder, and to increase the efficiency, a two-stage high-pressure pump, by whose lower stage the first pressure reservoir and by whose higher stage the second pressure reservoir are supplied.

Abstract: In a method for injecting fuel at at least two differently high fuel pressures via injectors into the combustion chamber of an internal combustion engine, the fuel injection at the lower fuel pressure takes place under stroke control, and the fuel injection at the higher fuel pressure takes place under pressure control. For a pre- and/or post-injection and/or a boot injection at the lower fuel pressure, the control chamber and via a check valve the nozzle chamber as well are connected to a low-pressure fuel supply, and that for a main injection at the higher fuel pressure, the nozzle chamber is connected to the high-pressure fuel supply.

Abstract: A fuel injection system has a pressure step-up unit, disposed between a pressure storage chamber and a nozzle chamber, whose pressure chamber communicates with the nozzle chamber via a pressure line. A bypass line connected to the pressure storage chamber is also provided. The bypass line communicates directly with the pressure line. The bypass line can be used for pressure injection and is disposed parallel to the pressure chamber, so that the bypass line is open regardless of the motion and position of a displaceable piston element in the pressure step-up unit. This enhances the flexibility of injection.

Abstract: An injection nozzle of a stroke-controlled fuel injection device has a control chamber for triggering a nozzle needle and also has a nozzle chamber connectable to a pressure booster. The communication between a differential chamber of the pressure booster and a leakage line and the communication between a control chamber and a leakage line are controllable with the aid of a common valve.

Abstract: In a pressure-controlled fuel injection system, a nozzle needle is subjected to pressure in the closing direction by a nozzle spring. A nozzle chamber for opening the nozzle needle is connectable to a pressure reservoir via a pressure line. A hydraulic device is embodied to reinforce the closing performance of the nozzle needle. As a result, a faster closing performance of the nozzle needle is achieved.