Gas injection valve for internal combustion engines

Abstract

The invention relates to a gas injection valve (10.1) comprising: a housing (11) which has a fuel inlet (22) and an injection valve seat (23) having an outwardly opening valve sealing surface (231); an injection valve element (31) which is designed to interact with the injection valve seat (23); wherein the injection valve element (31) has a control piston (311) which is guided in a sliding fit in a first guide recess (114), wherein a control needle (34) abuts an end face of the control piston (311) and is guided in a sliding fit in a control bore (116), wherein the control bore (116) connects the first guide recess (114) to a second guide recess (115) in which a hydraulic control piston (35) abutting an end face of the control needle (34) is guided in a sliding fit, wherein the gas injection valve (10.1) has a hydraulic control device (41) which is designed to adjust the hydraulic control piston (35) by changing a control pressure in a hydraulic control chamber (117) arranged in the second guide recess (115), wherein the control needle (34) and the injection valve element (31) can be moved by adjusting the hydraulic control piston (35).

Description

[0001] GAS INJECTION VALVE FOR INTERNAL COMBUSTION ENGINES

[0002] Field of the invention

[0003] The present invention relates to a gas injection valve for injecting gaseous fuel, in particular hydrogen or natural gas, into the combustion chamber of an internal combustion engine.

[0004] Background of the invention

[0005] In a gas combustion engine, an internal combustion engine is powered by a gaseous fuel, such as natural gas or hydrogen. When operated with high-quality fuel gases such as methane, high efficiencies with clean combustion and a good carbon dioxide (CCt) balance are possible. In terms of carbon dioxide (CCt) emissions, hydrogen is also considered a promising energy source, as the energy conversion of hydrogen in the combustion engine can be largely CCt-free and without carbon-containing pollutants such as carbon monoxide and hydrocarbons.

[0006] A fuel injection device with gaseous fuel is described, for example, in WO 2007 / 090228 A1. The fuel injection device comprises a solenoid coil, an armature coupled to a valve element configured to open and close a fuel valve when the solenoid coil is selectively energized and de-energized with current. The valve element is biased to the closed position by a biasing means. The fuel injection device comprises a control means, wherein the control means energizes the solenoid coil to cause a magnetic force to move the armature and the valve element to open the valve to an open position for delivering the fuel.The control means is arranged to calculate the difference between forces urging the valve to open and forces urging the valve to close, and to prevent the valve from opening further once an opening position has been reached at which the difference between the forces is at a predetermined value.

[0007] Description of the invention

[0008] In comparison to fuel injectors that inject gasoline or diesel, a sufficiently large injection cross-section or flow cross-section and the stroke of the injection valve element of the gas injector are of increased importance for a gas injector. Due to the lower energy density of the gas compared to a liquid fuel, in order to achieve a certain power output of the internal combustion engine, a gas injector generally requires a larger flow cross-section than an injection valve for a liquid fuel, with the same valve opening time. The required flow cross-section can be achieved, for example, by an injection valve element that opens outwards into the combustion chamber of the internal combustion engine and by an increased stroke of the injection valve element.However, the greater the distance between the injection valve element of the gas injection valve and the solenoid coil of the solenoid valve that adjusts the injection valve element due to the increased stroke, the lower the forces generated by the solenoid valve become with which the injection valve element can be adjusted, thereby limiting the possible flow. Furthermore, the requirement for an increased stroke conflicts with a precise and / or reproducible adjustment of the actuator or opening of the gas injection valve.

[0009] It is therefore an object of the invention to provide a gas injection valve which at least partially improves the prior art.

[0010] This object is achieved with a gas injection valve having the features of the independent claim. Advantageous embodiments of the invention are given in the dependent claims and in the present description and figures.

[0011] The invention relates to a gas injection valve for injecting gaseous fuel into the combustion chamber of an internal combustion engine, comprising a housing extending along a longitudinal axis, which has a fuel inlet and an injection valve seat with an outwardly opening valve sealing surface, a gas chamber arranged in the housing, which runs from the fuel inlet to the injection valve seat, an injection valve member arranged so as to be adjustable along the longitudinal axis, which is designed to cooperate with the injection valve seat, a compression spring which applies a closing force to the valve sealing surface of the injection valve member, a spring stop attached to the injection valve member, wherein the compression spring is supported at a first end relative to the housing in a fixed position on the housing and at a second end on the spring stop, wherein the injection valve member has a control piston,which is guided with a sliding fit in a first guide recess of the housing, wherein a control needle which is adjustable along the longitudinal axis rests on an end face of the injection valve member facing away from the injection valve seat and is guided with a sliding fit in a control bore of the housing, wherein the control bore is connected to a second guide recess in which a hydraulic control piston resting on an end face of the control needle facing away from the injection valve seat is guided with a sliding fit, wherein the gas injection valve has a hydraulic control device which is designed to adjust the hydraulic control piston along the longitudinal axis by changing a control pressure in a hydraulic control chamber arranged in the second guide recess, wherein the control needle and the injection valve member are movable along the longitudinal axis by adjusting the hydraulic control piston.

[0012] The injection process of the gas injection valve can therefore be controlled hydraulically using the hydraulic control device, which adjusts the hydraulic control piston. In comparison to direct magnetic control of the injection valve element in known gas injection valves, the injection valve element in the present gas injection valve can be adjusted considerably more quickly and precisely thanks to the hydraulic control. The hydraulic control chamber offers the option of setting the stroke and / or the opening or closing speed as desired by dimensioning the control chamber and / or controlling the control pressure. In addition, the same injector can be used with different gas pressures without having to change the injector or the dimensioning of the hydraulic control chamber, since the different gas pressures can be counteracted by varying the control pressure of the hydraulic control device.

[0013] The gas injection valve can also be used to separate the hydraulic circuit of the hydraulic control system from the gas chamber. The hydraulically controllable adjustment movement of the hydraulic control piston can be transmitted to the injection valve member by the control needle, which is guided with a sliding fit in the control bore connected to the second guide recess.

[0014] With the present invention, the advantages of precise control and rapid opening and closing of the injection valve member, which can be provided by a hydraulic control system, can be combined with a gas injection valve. Furthermore, a large stroke or opening stroke of the injection valve member required for gas injection can be provided without adversely affecting the actuating force.

[0015] Several of the alternative, desired green and climate-neutral fuels generally have poor ignition properties and can require comparatively high ignition energy for clean combustion in piston internal combustion engines. This can be particularly the case when the combustion process, as in most large engines, is a process with self-ignition and simultaneous high compression, such as the diesel engine. Since the high compression results in higher engine efficiency, i.e. lower fuel consumption, this can lead to significant operating cost savings for large engines, which typically have several thousand operating hours per year at high load.

[0016] To ignite the alternative fuels during auto-ignition, a small injection of diesel fuel at high pressure is typically used. This can be optimally provided by a micro-pilot injector or by an injector that allows the engine to operate up to full load on diesel fuel and provides only a small amount of pilot fuel to ignite the alternative fuel when the engine generates the high load with the alternative fuel.

[0017] The hydraulic control system for the gas injection valve disclosed herein can therefore advantageously also be operated with diesel fuel. A third, separate control fuel can then advantageously be omitted.

[0018] In one embodiment, the control needle projects into the second guide recess with an upper end facing away from the injection valve seat.

[0019] Due to this arrangement, the contact or the contact surface between the control needle and the hydraulic control piston can be arranged in the second guide recess. This can improve the separation of the hydraulic circuit of the hydraulic control from the gas chamber. Preferably, the control needle is guided with a sliding fit in the control bore, the hydraulic control piston with a sliding fit in the second guide recess and the control piston with a sliding fit in the first guide recess, so that leakage between the hydraulic control chamber and the gas chamber can be substantially prevented or minimized. Except for a small (tolerable) leakage, essentially a fluidic separation can therefore be achieved between the gas chamber and the hydraulic circuit or the hydraulic control chamber.In addition, the fluidic separation can be further improved by the fact that the control piston of the injection valve member is guided in a sliding fit in the first guide recess.

[0020] Preferably, the radial diameter of the control needle is smaller than the radial diameter of the hydraulic control piston and / or smaller than the radial diameter of the control piston of the injection valve member.

[0021] In one embodiment, the hydraulic control chamber is delimited axially in the direction away from the injection valve seat by the hydraulic control piston and in the direction facing the injection valve seat by a stop surface of the second guide recess.

[0022] In this embodiment, the hydraulic control chamber is therefore arranged between an end face of the hydraulic control piston facing the injection valve seat and the stop surface of the second guide recess. The stop surface of the second guide recess is preferably oriented horizontally with respect to the longitudinal axis and arranged below the hydraulic control piston with respect to the fuel flow direction.

[0023] In one embodiment, the injection valve member has an opening stroke between a closed position and an open position of the injection valve member, wherein in the closed position of the injection valve member the distance between the stop surface of the second guide recess and the end face of the hydraulic control piston facing the injection valve seat corresponds to the opening stroke of the injection valve member.

[0024] By dimensioning the hydraulic control chamber, particularly in the axial direction, the opening stroke or stroke of the injection valve member can therefore be defined. In particular, in contrast to direct magnetic control of the injection valve member in known gas injection valves, the actuating force of the injection valve member can be kept essentially constant, regardless of the opening stroke, by appropriately dimensioning the diameter of the control needle and / or the hydraulic control piston. The diameter of the control needle is preferably smaller than the diameter of the hydraulic control piston.

[0025] The distance between the stop surface of the second guide recess and the end face of the hydraulic control piston facing the injection valve seat in the closed position of the injection valve member can be adjusted by appropriately dimensioning the length of the control needle.

[0026] In the closed position of the injection valve member, the end face of the hydraulic control piston facing the injection valve seat is preferably spaced from the stop surface of the second guide recess by the amount of the opening stroke. In the open position of the injection valve member, the end face of the hydraulic control piston facing the injection valve seat preferably bears against the stop surface of the second guide recess.

[0027] In one embodiment, the hydraulic control device has an electromagnetically actuated control valve which is arranged off-axis to the injection valve member.

[0028] This allows the control valve to be arranged radially next to the second guide recess, thus keeping the length of the gas injection valve small. Furthermore, a lateral access from the control valve to the hydraulic

[0029] control room is possible.

[0030] In one embodiment, the control valve is fluidically connected to the hydraulic control chamber via a first transverse bore.

[0031] The control valve can therefore change the control pressure in the hydraulic control chamber via the first cross hole.

[0032] In one embodiment, the control valve has an electromagnetically actuated actuator arrangement with which the hydraulic control chamber can be connected to a control fluid return via a first throttle passage in a control open position and can be separated from the control fluid return in a control closed position, wherein the hydraulic control chamber is connected or connectable to a control fluid inlet of a control fluid supply chamber. The control fluid return is preferably a low-pressure return and has a lower pressure than the control fluid inlet pressure in the control fluid supply chamber. By connecting the hydraulic control chamber to the control fluid return via the first throttle passage in the control open position, the control pressure in the hydraulic control chamber is reduced, as a result of which the hydraulic control piston can be adjusted in the direction facing the injection valve seat.By adjusting the hydraulic control piston in the direction facing the injection valve seat, the control needle and the control piston of the injection valve member can be moved in the direction facing the injection valve seat in order to lift a valve member sealing surface of the injection valve member from the valve sealing surface of the injection valve seat and to open the gas injection valve.

[0033] When the hydraulic control chamber is separated from the control fluid return in the control closed position, the control pressure in the hydraulic control chamber is increased again by the connection to the control fluid inlet of the control fluid supply chamber, whereby the hydraulic control piston can be adjusted in the direction away from the injection valve seat. By adjusting the hydraulic control piston in the direction away from the injection valve seat, the control needle and the control piston of the injection valve member can be moved in the direction away from the injection valve seat in order to bring the valve member sealing surface of the injection valve member back into contact with the valve sealing surface of the injection valve seat and to close the gas injection valve.

[0034] In one embodiment, the control valve has an electromagnetically adjustable armature shaft with a tappet which, in the control open position, opens the connection between the first throttle passage and the control fluid return and, in the control closed position, separates the connection between the first throttle passage and the control fluid return.

[0035] In particular, the tappet can open a control fluid return outlet fluidically connected to the first throttle passage in the control open position and close the control fluid return outlet in the control closed position.

[0036] In one embodiment, the hydraulic control chamber is connected to the control fluid inlet via a second throttle passage. The first throttle passage can have a larger minimum diameter than the minimum diameter of the second throttle passage.

[0037] In the control closed position, the control pressure in the hydraulic control chamber is increased due to the inflow of control fluid through the second throttle passage into the hydraulic control chamber until the control pressure can reach the control fluid inlet pressure in the control fluid supply chamber.

[0038] In one embodiment, the first and second throttle passages are arranged in a double throttle cartridge.

[0039] The double throttle cartridge offers the advantage that the first throttle passage and the second throttle passage can be manufactured in a common component. Preferably, the first throttle passage is arranged above the second throttle passage with respect to the fuel flow direction.

[0040] In one embodiment, the double throttle cartridge has a cartridge transverse bore which is fluidically connected to the first transverse bore and into which the first and second throttle passages open.

[0041] A fluid connection between the first throttle passage and the hydraulic control chamber as well as a fluid connection between the second throttle passage and the hydraulic control chamber can therefore be provided via the cartridge cross-bore.

[0042] In one embodiment, the double throttle cartridge is press-fitted into a cartridge recess in the housing.

[0043] The double throttle cartridge can therefore be manufactured as a separate component and inserted into the cartridge recess. This allows, in particular, precise manufacturing of the first and second throttle passages.

[0044] In one embodiment, the double throttle cartridge has a groove into which the cartridge cross bore opens.

[0045] The groove allows the overlap area between the cartridge transverse bore and the first transverse bore to be enlarged, so that the fluid connection between the first transverse bore and the cartridge transverse bore can be ensured regardless of the rotational position of the double throttle cartridge about a vertical axis. The groove is preferably formed radially circumferentially on the end face of the double throttle cartridge.

[0046] In one embodiment, the control valve has a control valve member which, in the control closed position of the control valve, assumes a valve member open position in which the control valve member releases a first connection between the control fluid inlet and the hydraulic control chamber and, in the control open position of the control valve, assumes a valve member closed position in which the control valve member interrupts the first connection between the control fluid inlet and the hydraulic control chamber and separates the hydraulic control chamber from a valve chamber except for a third throttle passage.

[0047] In particular, the control valve can disconnect the connection between the first throttle passage and the control fluid return in the control closed position. Furthermore, the control valve can separate the valve chamber from the control fluid return in the control closed position and connect the valve chamber to the control fluid return in the control open position.

[0048] In the control open position of the control valve, control fluid can flow from the hydraulic control chamber into the valve chamber via the third throttle passage and from there into the control fluid return via the first throttle passage, so that the control pressure in the hydraulic control chamber drops and the hydraulic control piston is moved in the direction of the injection valve seat.

[0049] The connection of the valve chamber to and the separation of the valve chamber from the control fluid return can be achieved by the tappet described above, which can be pressed by the electromagnetically actuated actuator arrangement onto the control fluid return outlet fluidly connected to the valve chamber in order to close the control fluid return outlet and can be lifted from the control fluid return outlet in order to open it.

[0050] By connecting the valve chamber to the control fluid return, the control valve member can be brought into the valve member closed position in order to reduce the control pressure in the hydraulic control chamber and thereby move the control piston of the injection valve member towards the injection valve seat and thus raise the valve member sealing surface from the valve sealing surface of the injection valve seat.

[0051] By separating the valve chamber from the control fluid return, the control valve member can be brought into the valve member open position in order to increase the control pressure in the hydraulic control chamber by the inflow of control fluid from the control fluid supply chamber through the first connection and thereby move the control piston of the injection valve member away from the injection valve seat and thus press the valve member sealing surface onto the valve sealing surface of the injection valve seat.

[0052] At least a part of the valve chamber is preferably arranged between the control valve member and the control fluid return outlet.

[0053] The third throttle passage, which connects the hydraulic control chamber to the valve chamber, can be formed on the control valve member. The third throttle passage can also be formed on a head of the control valve member. In further variants, the third throttle passage can be formed between the control valve member and another component, such as, for example, through a gap between the control valve member and the housing. The third throttle passage formed on the control valve member can, on the side facing the control fluid return outlet, open into a blind bore cut out on the control valve member and belonging to the valve chamber.

[0054] In one embodiment, the control valve member is mushroom-shaped and has a shaft guided in a valve member guide recess of the housing and a head, wherein the control valve has a control valve seat formed on a side of the housing facing the head and cooperating with the head.

[0055] In one embodiment, the control valve member is disc-shaped and guided in a valve member guide recess of the housing, wherein the control valve has a control valve seat formed on a side of the housing facing the disc-shaped control valve member and cooperating with the disc-shaped control valve member.

[0056] Preferably, the disc-shaped control valve member is located in the valve member guide recess of the housing. With the mushroom-shaped control valve member, more stable control by the control valve can be provided, e.g. in comparison with a disc-shaped control valve member. Both the mushroom-shaped control valve member and the disc-shaped control valve member offer the advantage of enabling precise control using a small amount of control fluid. The gas injection valve therefore offers the possibility of utilizing the advantages of hydraulic control with a control valve having a control valve member.

[0057] In one embodiment, the control valve member releases a second connection between the control fluid inlet and the valve chamber in the valve member open position and interrupts the second connection between the control fluid inlet and the valve chamber in the valve member closed position.

[0058] Because the control valve member releases a second connection between the control fluid inlet and the valve chamber in the valve member open position, the valve chamber can be filled with control fluid via the second connection, which enables a faster opening movement of the control valve member. In particular, the second connection can improve the filling of the valve chamber compared to an injection valve in which the filling of the valve chamber takes place, for example, solely from the hydraulic control chamber or from a secondary control chamber connected to the hydraulic control chamber via a throttle passage. Advantageously, the valve chamber can therefore be filled via the second connection even with a small opening movement of the control valve member.

[0059] As far as the third throttle passage is concerned, it may advantageously be sufficient if the flow of the control fluid from the hydraulic control chamber or from a secondary control chamber connected to the hydraulic control chamber into the valve chamber through the third throttle passage causes the initially small opening movement of the control valve member, since the valve chamber can then be filled with a large quantity of control fluid via the second connection.

[0060] By interrupting the second connection between the control fluid inlet and the valve chamber in the valve member closed position of the control valve member, disadvantageous loss of control fluid and wear due to expansion of the control fluid from the control fluid supply chamber into the valve chamber during the injection process can be reduced or minimized, while by releasing the second connection, rapid filling of the valve chamber for the opening movement of the control valve member can be achieved.

[0061] In one embodiment, the hydraulic control chamber can be connected to the control fluid inlet of the control fluid supply chamber via a passage.

[0062] In the control closed position, the control pressure in the hydraulic control chamber is increased due to the inflow of control fluid through the passage into the hydraulic control chamber until the control pressure can reach the control fluid inlet pressure in the control fluid supply chamber.

[0063] In one embodiment, the control fluid supply chamber has an axial control fluid supply chamber section extending along the longitudinal axis, which is arranged off-axis to the injection valve member.

[0064] The off-axis arrangement of the control fluid supply chamber section allows the length of the gas injection valve to be kept short. Furthermore, the control fluid inlet opening for supplying the control fluid supply chamber with control fluid can be arranged off-axis relative to the injection valve element.

[0065] In one embodiment, the control fluid inlet is connected to the axial control fluid supply chamber section via a second transverse bore.

[0066] The control fluid inlet can therefore be supplied with control fluid from the control fluid supply chamber via the second transverse bore.

[0067] The axial control fluid supply chamber section and the control valve can in particular be arranged on opposite sides with respect to the second guide recess.

[0068] In one embodiment, the second guide recess is connected to the axial control fluid supply chamber section via a third transverse bore, wherein the third transverse bore opens into the second guide recess upstream of the hydraulic control piston.

[0069] The second guide recess can therefore have a system section that adjoins an end face of the hydraulic control piston facing away from the injection valve seat. The third transverse bore can accordingly open into the system section of the second guide recess. Due to the third transverse bore, the pressure in the system section of the second guide recess can be maintained at the control fluid inlet pressure.

[0070] With respect to the flow direction of the fuel, the system section can therefore be arranged in the second guide recess above the hydraulic control piston and the hydraulic control chamber below the hydraulic control piston. In one embodiment, the gas injection valve has a leakage outlet and a leakage discharge, which runs from the control space to the leakage outlet.

[0071] In one embodiment, the first guide recess has a circumferential annular space, and the gas injection valve has a leakage outlet and a leakage discharge which runs from the annular space to the leakage outlet.

[0072] Control fluid originating from a leak in the control bore can be collected in the annular space of the first guide recess or in the control space. This can be discharged through the leakage discharge to the leakage outlet. This prevents fuel from leaking from the gas chamber into the leakage outlet and / or into the control fluid return. Furthermore, leakage of control fluid from the control fluid supply chamber and / or from the control fluid return into the gas chamber through the control bore can be minimized or reduced.

[0073] Preferably, the leakage drain primarily or exclusively drains control fluid. Preferably, the leakage drain, in particular, does not drain fuel.

[0074] In particular, it is undesirable for fuel to enter the control fluid circuit, which is connected to the control fluid return, from the gas space and mix with the control fluid there. However, it is acceptable for a small amount of control fluid to enter the gas space.

[0075] In one embodiment, the leakage discharge has a check valve which is designed to open at an opening pressure which lies between a control fluid inlet pressure of the control fluid supply chamber and a gas chamber pressure of the gas chamber, wherein the opening pressure is preferably closer to the gas chamber pressure than to the control fluid inlet pressure.

[0076] In one embodiment, the opening pressure is less than 10% or approximately 10% higher than the gas space pressure.

[0077] With the check valve, which is set to the appropriate opening pressure, it is possible to ensure that the leakage vent is activated when it is needed to vent a leak. With a leakage vent and a check valve, additional sealing oil or sealant can also be dispensed with.

[0078] In an internal combustion engine with multiple cylinders, check valves can be arranged individually in / on each gas injection valve. In one variant, a common check valve can be arranged in / on a collective leakage vent, which collects the leakage vents from several gas injection valves.

[0079] In one embodiment, the check valve is arranged within the housing.

[0080] In one embodiment, the check valve is arranged outside the housing.

[0081] The check valve can be designed as a mechanically spring-loaded valve with a specific, set or adjustable opening pressure. Alternatively, the check valve can be designed as an electromagnetically controlled valve with an electrically or electronically adjustable opening pressure. The electrically or electronically adjustable opening pressure can be flexibly set to an optimal opening pressure required depending on the operating state of the internal combustion engine. For example, the opening pressure can be changed if the control fluid inlet pressure is varied depending on the load and speed for better control of the fuel injection of the internal combustion engine or if the gas-fuel pressure is varied.

[0082] In one embodiment, the leakage discharge is connected to the

[0083] Control fluid return connected.

[0084] The control fluid return and the leakage drain can therefore have the same (control fluid) outlet. A separate leakage outlet is then unnecessary, or the (control fluid) outlet can serve as the leakage outlet.

[0085] In one embodiment, the spring stop has a radially outer circumferential stop shoulder on which the second end of the compression spring is supported.

[0086] The compression spring can pull the injection valve member over the radially outer circumferential stop shoulder towards the injection valve seat, so that the valve member sealing surface is pressed with a closing force onto the valve sealing surface of the injection valve seat.

[0087] In one embodiment, the spring stop has a conical inner recess into which a conical section of the injection valve member is fitted.

[0088] When assembling the gas injection valve, the spring stop and the injection valve member can therefore be inserted separately into the housing. In one embodiment, a two-part fitting sleeve is arranged in the conical inner recess, into which the conical section of the injection valve member is positively received.

[0089] When assembling the gas injection valve, the injection valve member can first be guided through the conical inner recess of the spring stop, and then the two-part fitting sleeve can be inserted between the conical section of the injection valve member and the conical inner recess. The compression spring can then press the conical inner recess of the spring stop positively against the conical section via the fitting sleeve.

[0090] In one embodiment, the housing has a nozzle body and a control body, wherein the injection valve seat is formed on the nozzle body and the hydraulic control device is arranged in the control body, wherein the nozzle body is preferably detachably fastened to the control body by means of a union nut.

[0091] In one embodiment, the injection valve member has an actuating section which is connected to the control piston upstream of the control piston and which projects into a compression spring receptacle of the control body, the control needle resting on an end face of the actuating section.

[0092] By adjusting the control needle using the hydraulic control piston, the injection valve member can be moved along the longitudinal axis via the actuating section. In one embodiment, the first guide recess is formed in the nozzle body.

[0093] To guide the injection valve member in the nozzle body, the injection valve member preferably has a guide section with an enlarged radial diameter and one or more radially outwardly open recesses for the flow of fuel, wherein the guide section is guided in a guide bore of the nozzle body. The guide section is preferably arranged in the lower half, particularly preferably in the lower third or in the lower quarter of the injection valve member, i.e., in the vicinity of the injection valve seat.

[0094] Since the first guide recess also provides guidance of the injection valve member via the control piston, the formation of the first guide recess in the nozzle body offers the advantage that a radial misalignment of the first guide recess and the guide bore can be avoided, as can occur if the first guide recess is formed in a housing part other than the nozzle body, e.g. in the control body.

[0095] Preferably, the radial diameter of the first guide recess is equal to the radial diameter of the guide bore. In particular, the first guide recess and the guide bore can be formed by different sections of a single longitudinal bore in the nozzle body.

[0096] In one embodiment, the nozzle body has at least one transverse bore downstream or below the control piston, which connects a fuel inlet chamber arranged outside the nozzle body and connected to the fuel inlet with an interior of the nozzle body extending to the injection valve seat.

[0097] In this embodiment, the first guide recess is therefore arranged at a height between the compression spring receptacle and the at least one transverse bore. Through the transverse bore, the fuel can reach the interior of the nozzle body below the control piston and flow to the injection valve seat. The fuel inlet chamber can be arranged in the control body.

[0098] In one embodiment, the control bore connects the compression spring receptacle with the second guide recess.

[0099] The compression spring receptacle is therefore preferably arranged above the first guide recess with respect to the fuel flow direction. Due to the control piston being guided with a sliding fit in the first guide recess, the compression spring receptacle is preferably fluidically separated from the gas chamber except for a small (tolerable) leakage. By arranging the compression spring receptacle, which is fluidically separated from the gas chamber, between the first guide recess and the control bore, the fluidic separation of the hydraulic circuit from the gas chamber can be improved.

[0100] The compression spring is preferably arranged in the compression spring receptacle of the control body and is supported at the first end on the nozzle body in a fixed position relative to the housing. The compression spring is therefore preferably arranged in the compression spring receptacle in such a way that the actuating section of the injection valve member projects through the compression spring. In one embodiment, the conical section of the injection valve member is formed on the actuating section, the conical section being arranged between the end face of the injection valve member, against which the control needle rests, and the control piston.

[0101] The actuating section can therefore provide both the end face for interaction with the control needle and the conical section for fitting the spring stop.

[0102] In one embodiment, the control needle projects into the compression spring holder with a lower end facing the injection valve seat.

[0103] The contact or contact surface between the control needle and the injection valve member can therefore be arranged in the compression spring receptacle. This can improve the separation of the hydraulic circuit of the hydraulic control system from the gas chamber.

[0104] In one embodiment, the control piston is arranged at an end region facing away from the injection valve seat, wherein the control needle rests against an end face of the control piston.

[0105] In particular, in this embodiment, the upper end region of the injection valve member can be formed by the control piston.

[0106] In one embodiment, the control bore connects the first guide recess to the second guide recess. The first guide recess can therefore be formed below the control bore, adjacent to the control bore. Despite the structural connection between the first and second guide recesses by the control bore, leakage can be substantially prevented or minimized due to the control needle being guided with a sliding fit in the control bore.

[0107] In one embodiment, the first guide recess is formed in the control body. The control body can therefore provide a guide for the control piston.

[0108] In one embodiment, the control needle projects into the first guide recess with a first end facing the injection valve seat.

[0109] Due to this arrangement, the contact or contact surface between the control needle and the injection valve member can be arranged in the first guide recess. This can improve the separation of the hydraulic circuit of the hydraulic control system from the gas chamber.

[0110] In one embodiment, a control intermediate space is arranged in the first guide recess, which is delimited axially in the direction facing the injection valve seat by the control piston and in the direction facing away from the injection valve seat by a transverse surface of the first guide recess, wherein the distance between the transverse surface of the first guide recess and an end face of the control piston facing away from the injection valve seat is greater than the opening stroke of the injection valve member in the open position of the injection valve member.

[0111] Because the distance between the transverse surface of the first guide recess and the end face of the control piston facing away from the injection valve seat is greater than the opening stroke of the injection valve member in the open position of the injection valve member, it can be ensured that the injection valve member does not strike the transverse surface of the first guide recess during the closing process before the injection valve member comes into sealing contact with the injection valve seat and closes the gas injection valve.

[0112] Preferably, the distance between the transverse surface of the first guide recess and the end face of the control piston facing away from the injection valve seat in the closed position of the injection valve member is therefore greater than zero, preferably greater than one eighth, one quarter or half of the opening stroke.

[0113] Preferably, the control space is pressure-relieved. In particular, the control space preferably has a pressure that is lower by factors or orders of magnitude than the control fluid inlet pressure in a control fluid supply space.

[0114] By relieving pressure in the control space, free or improved mobility of the control piston can be provided.

[0115] In one embodiment, the fuel inlet is arranged in a side wall of the housing at a height between the first guide recess and the injection valve seat.

[0116] By arranging the fuel inlet in a side wall of the housing at a height between the first guide recess and the injector seat, the fuel inlet can lead directly into the gas chamber with a large cross-section. This can be particularly advantageous for a gas injector, since a large flow cross-section is generally desired for a gaseous fuel.

[0117] In one embodiment, the fuel inlet is connected to a fuel supply which is inclined with respect to the longitudinal axis.

[0118] By inclining the fuel supply, the gas injection valve can be made slimmer.

[0119] List of characters

[0120] Embodiments of the invention are explained in more detail with reference to the following figures and the associated description. They show schematically:

[0121] Fig.l shows a longitudinal section through an embodiment of a gas injection valve;

[0122] Fig.2 shows an enlarged section in an upper area of ​​the gas injection valve from Fig.l;

[0123] Fig.3 shows a longitudinal section through an embodiment of a gas injection valve;

[0124] Fig.4a an enlarged section in an upper

[0125] Area of ​​the gas injection valve from Fig.3; Fig. 4b an enlarged section in an upper area of ​​an embodiment of a

[0126] Gas injection valve with a leakage vent;

[0127] Fig. 4c shows an enlarged section in an upper area of ​​an embodiment of a

[0128] Gas injection valve with a leakage vent;

[0129] Fig. 5 shows a further enlarged section of the area from Fig. 4a;

[0130] Fig. 6 is a cross-section along the line AA in Fig. 2;

[0131] Fig. 7 shows a longitudinal section through an embodiment of a gas injection valve.

[0132] Description of exemplary embodiments

[0133] In the description of the figures, the same reference symbols are used for corresponding parts of the embodiments.

[0134] Figure 1 shows an embodiment of a gas injection valve 10.1 in longitudinal section. The gas injection valve 10.1 has a housing 11 extending along a longitudinal axis L, which housing 11 comprises a fuel inlet 22 arranged in a side wall of the housing 11 and an injection valve seat 23 with an outwardly opening valve sealing surface 231. A gas chamber 21 arranged in the housing 11 runs from the fuel inlet 22 to the injection valve seat 23. The housing 11 further has a control body 111 and a nozzle body 112, which is fastened to the control body by a union nut 113.

[0135] 111 is attached .

[0136] An injection valve member 31 is arranged so as to be adjustable along the longitudinal axis L and is designed to interact with the injection valve seat 23. The injection valve member 31 has a valve member sealing surface 312 which can be brought into sealing engagement with the valve sealing surface 231 of the injection valve seat 23 to close the gas injection valve 10.1 and can be lifted off the valve sealing surface 231 to open the gas injection valve 10.1. In the housing 11, a

[0137] A compression spring 32 is arranged which applies a closing force to the valve sealing surface 231 of the injection valve member 31. To open the gas injection valve 10.1, the injection valve member 31 is moved against the spring force of the compression spring 32 in the direction of the injection valve seat 23, so that the valve member sealing surface 312 moves away from the valve sealing surface 231. The compression spring 32 is supported with its downstream end relative to the housing 11 on the nozzle body 112 in a stationary manner and with its upstream end on a spring stop 33 attached to the injection valve member 31. The spring stop 33 has a radially outer circumferential stop shoulder 331 on which the upstream end of the compression spring 32 is supported. The spring stop 33 has a conical inner recess into which a conical section 313 of the injection valve member 31 is fitted.In the conical inner recess there is also arranged a two-part fitting sleeve 332 into which the conical section 313 of the injection valve member 31 is received in a form-fitting manner. The injection valve member has, in the end region facing away from the injection valve seat 23, a control piston 311 which is guided with a sliding fit in a first guide recess 114 of the control body 111. A control needle 34 which is adjustable along the longitudinal axis L and is guided with a sliding fit in a control bore 116 of the control body 111 rests on an upstream or downstream end face of the control piston 311. The control needle 34 is adjustable along the longitudinal axis L and is guided with a sliding fit in a control bore 116 of the control body 111. The control bore 116 connects the first guide recess 114 to a second guide recess 115 in which a The hydraulic control piston 35 is guided in a sliding fit on the end face of the control needle 34 facing away from the injection valve seat 23.

[0138] The gas injection valve 10 . 1 has a hydraulic control device 41 , with which, as explained in more detail in connection with Fig . 2, the hydraulic control piston 35 can be adjusted along the longitudinal axis L by changing a control pressure in a hydraulic control chamber 117 arranged in the second guide recess 115 . By adjusting the hydraulic control piston 35 , the control needle 34 and thus the injection valve member 31 can be moved along the longitudinal axis L .

[0139] Figure 2 shows an enlarged section in an upper region of the gas injection valve 10. 1 from Figure 1. The hydraulic control device has an electromagnetically actuated control valve 42, which is arranged off-axis to the injection valve member 31. The control valve 42 is fluidically connected to the hydraulic control chamber 117 via a first transverse bore 51. The control valve 42 has an electromagnetically actuated actuator arrangement 44, with which the hydraulic control chamber 117 can be connected to a control fluid return 62 via a first throttle passage 421 in a control open position of the control valve 42 and can be separated from the control fluid return 62 in a control closed position of the control valve 42.For this purpose, the control valve 42 has an electromagnetically adjustable armature shaft 621 with a tappet 622, which in the control open position opens the connection between the first throttle passage 421 and the control fluid return 62 and in the control closed position closes the connection between the first throttle passage 421 and the.

[0140] Control fluid return 62 separates .

[0141] The hydraulic control chamber 117 is further connected via a second throttle passage 422 to a control fluid inlet 63, which is connected via a second transverse bore 52 to an axial control fluid supply chamber section 611 of a control fluid supply chamber 61, which is arranged off-axis with respect to the injection valve member 31. The control fluid inlet 63 is therefore supplied with control fluid from the control fluid supply chamber 61 via the second transverse bore 52. The axial control fluid supply chamber section 611 and the control valve 42 are arranged on opposite sides with respect to the second guide recess 115. The second guide recess 115 is connected to the axial control fluid supply chamber section 611 via a third transverse bore 53. The third transverse bore 53 opens upstream of the hydraulic control piston 35 into a system section 1151 of the second guide recess 115.The system section 1151 is therefore arranged above the hydraulic control piston 35, and the hydraulic control chamber 117 is arranged below the hydraulic control piston 35. The hydraulic control chamber 117 is axially delimited in the direction away from the injection valve seat 23 by the hydraulic control piston 35 and in the direction toward the injection valve seat 23 by a stop surface 1152 of the second guide recess 115.

[0142] The control fluid return 62 is a low-pressure return and has a lower pressure than the control fluid inlet pressure in the control fluid supply chamber 61. By connecting the hydraulic control chamber 117 to the control fluid return 62 via the first throttle passage 421 in the control open position, the control pressure in the hydraulic control chamber 117 is reduced, as a result of which the hydraulic control piston 35 is adjusted downwards or in the direction facing the injection valve seat. By adjusting the hydraulic control piston 35 in the direction facing the injection valve seat, the control needle 34 and the control piston 311 of the injection valve member 31 are moved in the direction facing the injection valve seat in order to lift the valve member sealing surface 312 of the injection valve member 31 from the valve sealing surface 231 of the injection valve seat and the gas injection valve 10. 1 to open .The hydraulic control piston 35 moves in the direction of the injection valve seat until its lower end face comes into contact with the bottom of the second guide recess 115 formed by a transverse surface 1152. The distance between the lower end face of the hydraulic control piston 35 facing the injection valve seat and the bottom 1152 of the second guide recess 115 therefore corresponds to the opening stroke of the injection valve member 31. When the hydraulic control chamber 117 is separated from the control fluid return 62 in the control closed position, the control pressure in the hydraulic control chamber 117 is increased again due to the inflow of control fluid through the connection to the control fluid inlet 63 via the second throttle passage 422, as a result of which the hydraulic control piston 35 is again moved upwards or in the direction away from the injection valve seat.By adjusting the hydraulic control piston 35 in the direction away from the injection valve seat, the control needle 34 and the control piston 311 of the injection valve member 31 are moved in the direction away from the injection valve seat due to the spring force of the compression spring 32, so that the valve member sealing surface 312 of the injection valve member 31 comes into contact again with the valve sealing surface 231 of the injection valve seat and the gas injection valve 10 . 1 is closed.

[0143] The first throttle passage 421 and the second throttle passage 422 are arranged in a double throttle cartridge 43, which is press-fitted into a cartridge recess of the control body 111. The first throttle passage 421 has a larger minimum diameter than the minimum diameter of the second throttle passage 422 and is arranged above the second throttle passage 422 with respect to the flow direction of the fuel. The double throttle cartridge 43 has a cartridge transverse bore 431, which is fluidically connected to the first transverse bore 51. Both the first throttle passage 421 and the second throttle passage 422 open into the cartridge transverse bore 431. The double throttle cartridge 43 has a groove 432 which is formed radially around the front side of the double throttle cartridge 43 and into which the cartridge transverse bore 431 opens.The groove 432 ensures the fluid connection between the first transverse bore 51 and the cartridge transverse bore 431 regardless of a rotational position of the double throttle cartridge 43 about a vertical axis.

[0144] In the first guide recess 114 there is arranged a control intermediate space 118 which is delimited downstream or in the direction facing the injection valve seat by an upper end face of the control piston 311 and upstream or in the direction facing away from the injection valve seat by the ceiling of the first guide recess 114 formed by a transverse surface. In the open position of the injection valve member 31, the distance between the ceiling of the first guide recess 114 and the end face of the control piston 311 facing away from the injection valve seat is greater than the opening stroke of the injection valve member 31. In the closed position of the injection valve member 31, the distance between the ceiling of the first guide recess 114 and the upper end face of the control piston 311 is therefore greater than zero.

[0145] Figure 3 shows a longitudinal section through an embodiment of a gas injection valve 10.2. The gas injection valve 10.2 has a structure corresponding to the embodiment of the gas injection valve 10.1 shown in Figure 1, except for the hydraulic control device 41 and the bores leading to it. For the sake of simplicity, only the injection valve member 31 and its control piston 311, the control needle 34 and the hydraulic control piston 35 are shown in Figure 3. An enlarged section of an upper region of the gas injection valve from Figure 3 is shown in Figure 4a. The hydraulic control device has an electromagnetically actuated control valve 42 which is fluidically connected to the hydraulic control chamber 117 via a first transverse bore 51.The control valve 42 has an electromagnetically actuated actuator arrangement 44 with which the hydraulic control chamber 117 can be connected to a control fluid return 62 in a control open position of the control valve 42 and can be separated from the control fluid return 62 in a control closed position of the control valve 42.

[0146] The hydraulic control chamber 117 is further connectable to a control fluid inlet 63, which is connected via a second transverse bore 52 to a control fluid supply chamber section 611 of a control fluid supply chamber 61. The second transverse bore 52 does not run in the plane of the drawing and is accordingly shown in dashed lines. In particular, the second transverse bore 52 leads past the second guide recess 115 and the hydraulic control piston 35. The second guide recess 115 is connected to the control fluid supply chamber section 611 via a third transverse bore 53, which opens upstream of the hydraulic control piston 35 into a system section 1151 of the second guide recess 115.

[0147] Figure 4b shows a section in an upper region of an embodiment of a gas injection valve 10. 3 with a leakage discharge 119, which runs from the control intermediate chamber 118 to a leakage outlet 1191. The leakage discharge 119 has a check valve 1192, which is designed to open at an opening pressure that lies between the control fluid inlet pressure of the control fluid supply chamber 61 and the gas chamber pressure of the gas chamber. The opening pressure is preferably closer to the gas chamber pressure than to the control fluid inlet pressure.

[0148] Figure 4c shows a section in an upper region of an embodiment of a gas injection valve 10. 4 with a leakage discharge 119, which runs from the control intermediate space 118 to the control fluid return 62 or is connected to the control fluid return 62. The control fluid return 62 and the leakage discharge 119 therefore have the same (control fluid) outlet, so that a separate leakage outlet can be dispensed with or the (control fluid) outlet serves as a leakage outlet. The leakage discharge 119 leads past the first transverse bore 51 and the second transverse bore 52, i.e. the leakage discharge 119 does not cross the first and second transverse bores 51, 52.

[0149] Figure 5 shows a further enlarged section of the area from Figure 4a. The control valve 42 has a control valve member 423 which, in the control closed position of the control valve 42, assumes a valve member open position in which the control valve member 423 releases a first connection between the control fluid inlet 63 and the hydraulic control chamber 117. In the control open position of the control valve 42, when the actuator arrangement 44 is energized, the control valve member 423 assumes a valve member closed position in which the control valve member 423 interrupts the first connection between the control fluid inlet 63 and the hydraulic control chamber 117 and separates the hydraulic control chamber 117 from a valve chamber 425 except for a third throttle passage 424.In the control open position of the control valve 42, control fluid can flow from the hydraulic control chamber 117 into the valve chamber 425 via the third throttle passage 424 and from there into the control fluid return 62 via the first throttle passage 421, so that the control pressure in the hydraulic control chamber 117 drops and the hydraulic control piston 35 is moved downwards or in the direction of the injection valve seat.

[0150] The control valve member 423 is mushroom-shaped and has a shaft 4231 guided in a valve member guide recess in the housing 11 or the control body 111 and a head 4232. A bore 426, which is part of the valve chamber 425, is formed through the shaft 4231 up to a part of the head 4232. The bore 426 is part of the valve chamber 425. The housing 11 or the control body 111 has a valve member insert 428 in which the valve member guide recess is formed. The control valve 42 has a control valve seat formed on a side of the housing 11 or the valve member insert 428 facing the head 4232 and interacting with the head 4232. In the valve member closed position, the head 4232 rests against the valve member insert 428 via the control valve seat. The housing 11 or the control body 111 has a valve member stop 1111 against which the head 4232 can abut in the valve member open position.In the control closed position of the control valve 42 or the valve member open position, the control valve member 423 can assume an indi f ferent position after abutting the valve member stop 1111, in which the control valve member 423 from.

[0151] Valve member stop 1111 is raised. The hydraulic control chamber 117 can be connected to the control fluid return 62 via the first throttle passage 421, which is formed in the valve member insert 428. For this purpose, the control valve 42 has an electromagnetically adjustable armature shaft 621 with a tappet 622, which opens the connection between the first throttle passage 421 and the control fluid return 62 in the control open position and separates the connection between the first throttle passage 421 and the control fluid return 62 in the control closed position. In the valve member open position of the control valve member 423, the hydraulic control chamber 117 is connected to the control fluid inlet 63 of the control fluid supply chamber 61 via a passage 4222 formed in the valve member insert 428, wherein the control fluid inlet 63 is connected to the control fluid supply chamber section 611 of the control fluid supply chamber 61 via the second transverse bore 52.

[0152] A fourth throttle passage 427 is further formed in the valve member insert 428, via which the valve chamber 425 can be filled with control fluid from the control fluid supply chamber 61 in the control closed position of the control valve 42 in order to quickly open the control valve member 423, i.e. to bring it from the valve member closed position into the valve member open position, in which the first connection between the control fluid inlet 63 and the hydraulic control chamber 117 is released through the passage 4222.

[0153] The control valve 42 with the mushroom-shaped control valve member 423 can, in certain embodiments, be designed correspondingly to the intermediate valves with a mushroom-shaped intermediate valve member described, for example, in the publications WO 2021 / 165275 A1, WO 2020 / 260285 A1, and WO 2016 / 041739 A1. The corresponding disclosure of these publications, particularly concerning the mushroom-shaped valve member, is therefore incorporated by reference into the present disclosure. For example, instead of the fourth throttle passage 427, a releasable and interruptible second connection between the control fluid inlet and the valve chamber, as disclosed in WO 2021 / 165275 A1, can be provided.

[0154] The various bores of the gas injection valve, such as the first transverse bore 51, the second transverse bore 52, and / or the third transverse bore 53, do not have to be located in the same plane, such as the plane of the drawing. In particular, the second transverse bore 52, for example, does not cross the control bore 116, but rather runs past it. Those bores that are not located in the plane of the drawing are shown in dashed lines in the figures.

[0155] The arrangement of the bores of the gas injection valve 10.1 is shown in Figure 6, which shows a cross-section along line AA in Figure 2. The control needle 34 and the hydraulic control piston 35 are arranged centrally in the control body 111. The second transverse bore 52 runs diagonally in Figure 6 on the left half of the control body 111 between the control fluid supply chamber 61 and the control fluid inlet 63. The third transverse bore 53 runs at a different angle between the control fluid supply chamber 61 and the system section arranged above the hydraulic control piston 35. The first transverse bore 51 runs at a different angle between the hydraulic control chamber arranged below the hydraulic control piston 35 and the control valve. Figure 7 shows an embodiment of a gas injection valve.

[0156] 10 . 5 in partial longitudinal section. The gas injection valve 10 . 5 has a housing 11 extending along a longitudinal axis L, which comprises a control body 111 and a nozzle body 112. The nozzle body 112 projects into a receiving recess 1112 of the control body 111. The control body 111 has a compression spring receptacle 120, into which an upper end portion 1123 of the nozzle body 112 is fitted.

[0157] The injection valve member 31 has an actuating section 315 which projects into the compression spring receptacle 112 and against whose end face the control needle 34 rests. The control needle 34 is guided with a sliding fit in the control bore 116 which connects the second guide recess 115 to the compression spring receptacle 120. The control needle 34 projects into the compression spring receptacle 120. As in the embodiments shown in the preceding figures, the hydraulic control piston 35 can be adjusted along the longitudinal axis L by changing the control pressure in the hydraulic control chamber 117 arranged in the second guide recess 115. By adjusting the hydraulic control piston 35, the control needle 34 and thus the injection valve member 31 can be moved along the longitudinal axis L.

[0158] A compression spring 32 is arranged in the compression spring receptacle 120 and is supported at a first end on the nozzle body 112 in a stationary manner relative to the housing. A conical section 313 is formed on the actuating section 315 of the injection valve member 31 and is fitted into a spring stop 33. As in the embodiments of the preceding figures, a two-part fitting sleeve is arranged between the spring stop 33 and the conical section 313, in which the conical section 313 of the injection valve member is received in a form-fitting manner. A second end of the compression spring 32 is supported on the spring stop 33, so that the injection valve member 31 is subjected to a closing force on the valve sealing surface of the injection valve seat 23.

[0159] The actuating section 315 is connected to the control piston 311 upstream of a control piston 311 of the injection valve member 31. The control piston 311 is guided with a sliding fit in a first guide recess 114 which is formed in the nozzle body 112. Because the control piston 311 is guided with a sliding fit in the first guide recess 114, the compression spring receptacle 120 is fluidically separated from the gas chamber 21 except for a small (tolerable) leakage. The nozzle body 112 has a plurality of transverse bores 1121 downstream of the control piston 311, which connect a fuel inlet chamber 222 connected to the fuel inlet 22 with the interior space 211 of the nozzle body 112 extending to the injection valve seat 23. The first guide recess 114 is therefore arranged at a height between the compression spring receptacle 120 and the transverse bores 1121. The fuel inlet chamber 222 is arranged in the control body 111.

[0160] In a lower region, the injection valve member 31 has a guide section 314 with an enlarged radial diameter and a plurality of recesses open radially outwards for the flow of fuel. The guide section 314 is guided in a guide bore 1122 of the nozzle body 112, wherein the radial diameter of the first guide recess 114 is equal to the radial diameter of the guide bore 1122. The first guide recess 114 and the guide bore 1122 are formed by different sections of a single longitudinal bore in the nozzle body 112 and are therefore precisely aligned with one another. This makes it possible to provide reliable guidance of the injection valve member 31 in the housing 11.

[0161] A fuel supply 221 extends between the fuel inlet 22 and the fuel inlet chamber 222, which fuel supply is inclined with respect to the longitudinal axis L and forms an acute angle with the longitudinal axis L in the upstream direction. In comparison to the embodiments shown in the preceding figures, in Figure 7 the longitudinal section is taken along a longitudinal plane rotated by approximately 90°, so that the hydraulic control device is not visible in the longitudinal section shown. The hydraulic control device can be designed as in the gas injection valve 10.1 according to Figures 1-2 or the gas injection valves 10.2-10.4 according to Figures 3-5.

Claims

Patent claims 1. Gas injection valve (10.1, 10.2, 10.3, 10.4, 10.5) to Injecting gaseous fuel into the combustion chamber of an internal combustion engine, comprising a housing (11) extending along a longitudinal axis (L), which has a fuel inlet (22) and an injection valve seat (23) with an outwardly opening valve sealing surface (231), a gas chamber (21) arranged in the housing (11), which runs from the fuel inlet (22) to the injection valve seat (23), an injection valve member (31) arranged so as to be adjustable along the longitudinal axis (L) and designed to cooperate with the injection valve seat (23), a compression spring (32) which applies a closing force to the injection valve member (31) on the valve sealing surface (231), a spring stop (33) attached to the injection valve member (31), wherein the compression spring (32) is fixed at a first end relative to the housing (11) on the housing (11) and is supported at a second end on the spring stop (33),wherein the injection valve member (31) has a control piston (311) which is guided in a sliding fit in a first guide recess (114) of the housing (11), wherein a control needle (34) which is adjustable along the longitudinal axis (L) bears against an end face of the injection valve member (31) facing away from the injection valve seat (23) and is guided in a sliding fit in a control bore (116) of the housing (11), wherein the control bore (116) is connected to a second guide recess (115) in which a hydraulic control piston (35) bearing against an end face of the control needle (34) facing away from the injection valve seat (23) is guided in a sliding fit, wherein the gas injection valve (10.1, 10.2, 10.3, 10.4) has a hydraulic control device (41) which is designed to adjust the hydraulic control piston (35) along the longitudinal axis (L) by changing a control pressure in a hydraulic control chamber (117) arranged in the second guide recess (115), wherein the control needle (34) and the Injector valve element (31) can be moved along the longitudinal axis (L) by adjusting the hydraulic control piston (35).

2. Gas injection valve (10.1, 10.2, 10.3, 10.4, 10.5) according to claim 1, characterized in that the control needle (34) projects into the second guide recess (115) with an upper end facing away from the injection valve seat (23).

3. Gas injection valve (10.1, 10.2, 10.3, 10.4, 10.5) according to one of the preceding claims, characterized in that the hydraulic control chamber (117) axially delimited in the direction away from the injection valve seat (23) by the hydraulic control piston (35) and in the direction facing the injection valve seat (23) by a stop surface (1152) of the second guide recess (115).

4. Gas injection valve (10.1, 10.2, 10.3, 10.4, 10.5) according to claim 3, characterized in that the injection valve member (31) has an opening stroke between a closed position and an open position of the injection valve member (31), wherein in the Closed position of the injection valve member (31) of the Distance between the stop surface (1152) of the second guide recess (115) and a The end face of the hydraulic control piston (35) facing the injection valve seat (23) corresponds to the opening stroke of the injection valve member (31).

5. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to one of the preceding claims, characterized in that the hydraulic control device (41) has an electromagnetically actuated control valve (42) which is arranged off-axis to the injection valve member (31).

6. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to claim 5, characterized in that the control valve (42) is fluidically connected to the hydraulic control chamber (117) via a first transverse bore (51).

7. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to claim 5 or 6, characterized in that the control valve (42) an electromagnetically actuated actuator arrangement (44), with which the hydraulic control chamber (117) can be connected to a control fluid return (62) via a first throttle passage (421) in a control open position and can be separated from the control fluid return (62) in a control closed position, wherein the hydraulic control chamber (117) is connected to a control fluid inlet (63) of a control fluid supply chamber (61) is connected or connectable.

8. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to claim 7, characterized in that the control valve (42) has an electromagnetically adjustable armature shaft (621) with a tappet (622) which, in the control open position, opens the connection between the first throttle passage (421) and the control fluid return (62) and, in the control closed position, separates the connection between the first throttle passage (421) and the control fluid return (62).

9. Gas injection valve (10.1) according to claim 7 or 8, characterized in that the hydraulic control chamber (117) is connected to the control fluid inlet (63) of the control fluid supply chamber (61) via a second throttle passage (422).

10. Gas injection valve (10.1) according to claim 9, characterized in that the first throttle passage (421) has a larger minimum diameter than the minimum diameter of the second throttle passage (422).

11. Gas injection valve (10.1) according to claim 9 or 10, characterized in that the first and the second Throttle passage (421, 422) in a Double throttle cartridge (43) are arranged.

12. Gas injection valve (10.1) according to claim 11, characterized in that the double throttle cartridge (43) has a cartridge transverse bore (431) which is fluidically connected to the first transverse bore (51) and into which the first and second throttle passages (421, 422) open.

13. Gas injection valve (10.1) according to claim 11 or 12, characterized in that the double throttle cartridge (43) is press-fitted into a cartridge recess of the housing (11).

14. Gas injection valve (10.1) according to one of claims 11 to 13, characterized in that the Double throttle cartridge (43) has a groove (432) into which the cartridge transverse bore (431) opens.

15. Gas injection valve (10.1) according to claim 14, characterized in that the groove (432) is formed radially circumferentially on the end face of the double throttle cartridge (43).

16. Gas injection valve (10.2, 10.3, 10.4) according to claim 7 or 8, characterized in that the control valve (42) has a control valve member (423) which, in the control closed position of the control valve (42), assumes a valve member open position in which the control valve member (423) releases a first connection between the control fluid inlet (63) and the hydraulic control chamber (117) and in the control open position of the control valve (42) assumes a valve member closed position in which the control valve member (423) interrupts the first connection between the control fluid inlet (63) and the hydraulic control chamber (117) and separates the hydraulic control chamber (117) from a valve chamber (425, 426) except for a third throttle passage (424).

17. Gas injection valve (10.2, 10.3, 10.4) according to claim 16, characterized in that the control valve member (423) is mushroom-shaped and has a shaft (4231) guided in a valve member guide recess of the housing (11) and a head (4232), wherein the control valve (42) has a control valve seat formed on a side of the housing (11) facing the head (4232) and cooperating with the head (4232).

18. Gas injection valve according to claim 16, characterized in that the control valve member is disc-shaped and is guided in a valve member guide recess of the housing, wherein the control valve has a control valve seat formed on a side of the housing facing the disc-shaped control valve member and cooperating with the disc-shaped control valve member 19. Gas injection valve according to one of claims 16 to 18, characterized in that the control valve member in the valve member open position releases a second connection between the control fluid inlet and the valve chamber and in the valve member closed position the second connection between the control fluid inlet and the valve chamber.

20. Gas injection valve (10.2, 10.3, 10.4) according to one of the Claims 16 to 19, characterized in that the hydraulic control chamber (117) can be connected to the control fluid inlet (63) of the control fluid supply chamber (61) via a passage (4222).

21. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to one of claims 7 to 20, characterized in that the control fluid supply chamber (61) has an axial Control fluid supply chamber section (611) which is arranged off-axis to the injection valve member (31).

22. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to claim 21, characterized in that the control fluid inlet (63) is connected to the axial control fluid supply chamber section (611) via a second transverse bore (52).

23. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to claim 21 or 22, characterized in that the second guide recess (115) is connected to the axial control fluid supply chamber section (611) via a third transverse bore (53), wherein the third transverse bore (53) opens into the second guide recess (115) upstream of the hydraulic control piston (35).

24. Gas injection valve (10.3, 10.4) according to one of the preceding claims, characterized in that the gas injection valve (10.3, 10.4) has a leakage outlet (1191) and a leakage discharge (119) which from the control gap (118) to the leakage outlet (1191).

25. Gas injection valve (10.3) according to claim 24, characterized in that the leakage discharge (119) has a check valve (1192) which is designed to open at an opening pressure which lies between a control fluid inlet pressure of the control fluid supply chamber (61) and a gas chamber pressure of the gas chamber (21), wherein the opening pressure is preferably closer to the gas chamber pressure than to the control fluid inlet pressure.

26. Gas injection valve according to claim 25, characterized in that the opening pressure is less than 10% or approximately 10% higher than the gas chamber pressure.

27. Gas injection valve (10.3) according to claim 25 or 26, characterized in that the check valve (1192) is arranged within the housing (11).

28. Gas injection valve according to claim 25 or 26, characterized in that the check valve is arranged outside the housing.

29. Gas injection valve (10.4) according to claim 7 and one of claims 24 to 28, characterized in that the leakage discharge (119) is connected to the control fluid return (62).

30. Gas injection valve (10.1, 10.2, 10.3, 10.4, 10.5) according to one of the preceding claims, characterized in that the spring stop (33) has a radially outer circumferential stop shoulder (331) on which which the second end of the compression spring (32) is supported.

31. Gas injection valve (10.1, 10.2, 10.3, 10.4, 10.5) according to claim 30, characterized in that the spring stop (33) has a conical inner recess into which a conical section (313) of the injection valve member (31) is fitted.

32. Gas injection valve (10.1, 10.2, 10.3, 10.4, 10.5) according to claim 31, characterized in that a two-part fitting sleeve (332) is arranged in the conical inner recess, in which the conical section (313) of the injection valve member (31) is received in a form-fitting manner.

33. Gas injection valve (10.1, 10.2, 10.3, 10.4, 10.5) according to one of the preceding claims, characterized in that the housing (11) has a nozzle body (112) and a control body (111), wherein the injection valve seat (23) is formed on the nozzle body (112) and the hydraulic control device (41) is arranged in the control body (111), wherein the nozzle body (112) is preferably detachably fastened to the control body (111) with a union nut (113).

34. Gas injection valve (10.1, 10.2, 10.3, 10.4, 10.5) according to one of the preceding claims, characterized in that the radial diameter of the control needle (34) is smaller than the radial diameter of the hydraulic control piston (35).

35. Gas injection valve (10.5) according to one of the preceding claims, characterized in that the injection valve member (31) has an actuating section (315) which adjoins the control piston upstream of the control piston (311) and which projects into a compression spring receptacle (120) of the control body (111), the control needle (34) resting on an end face of the actuating section.

36. Gas injection valve (10.5) according to claim 33 and claim 35, characterized in that the first guide recess (114) is formed in the nozzle body (112).

37. Gas injection valve (10.5) according to claim 36, characterized in that the nozzle body (112) downstream of the control piston (311) has at least one transverse bore (1121) which has a fuel inlet chamber (222) arranged outside the nozzle body and connected to the fuel inlet (22) with a Injection valve seat (23) extending interior space (211) of the nozzle body.

38. Gas injection valve (10.5) according to one of claims 35 to 37, characterized in that the control bore (116) connects the compression spring receptacle (120) with the second guide recess (115).

39. Gas injection valve (10.5) according to claim 38, characterized in that the compression spring (32) in the Compression spring receptacle (120) of the control body (111) is arranged and is supported at the first end on the nozzle body (112) in a stationary manner relative to the housing (11).

40. Gas injection valve (10.5) according to claim 31 and claim 39, characterized in that the conical section (313) of the injection valve member (31) is formed on the actuating section (315), wherein the conical section is arranged between the end face of the injection valve member, against which the control needle (34) rests, and the control piston (311).

41. Gas injection valve (10.5) according to one of claims 35 to 40, characterized in that the control needle (34) projects into the compression spring receptacle (120) with a lower end facing the injection valve seat (23).

42. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to one of claims 1 to 34, characterized in that the control piston (311) is arranged at an end region facing away from the injection valve seat (23), wherein the control needle (34) bears against an end face of the control piston (311).

43. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to claim 42, characterized in that the control bore (116) connects the first guide recess (114) with the second guide recess (115).

44. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to claim 43, characterized in that the first guide recess (114) is formed in the control body (111).

45. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to one of claims 42 to 44, characterized in that the control needle (34) is provided with a facing first end into the first guide recess (114) protrudes.

46. ​​Gas injection valve (10.1, 10.2, 10.3, 10.4) according to one of claims 42 to 45, characterized in that a control intermediate space (118) is arranged in the first guide recess (114), which is axially delimited in the direction facing the injection valve seat (23) by the control piston (311) and in the direction facing away from the injection valve seat (23) by a transverse surface of the first guide recess (114), wherein the distance between the transverse surface of the first guide recess (114) and an end face of the control piston (311) facing away from the injection valve seat (23) in the open position of the injection valve member (31) is greater than the opening stroke of the injection valve member (31).

47. Gas injection valve (10.1, 10.2, 10.3, 10.4) according to one of the preceding claims, characterized in that the fuel inlet (22) is arranged in a side wall of the housing (11) at a height between the first guide recess (114) and the injection valve seat (23).

48. Gas injection valve (10.5) according to one of the preceding claims, characterized in that the fuel inlet (22) is connected to a fuel supply (221) which is inclined with respect to the longitudinal axis (L).

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