DE102016220071A1 - Servo injector with minimal valve volume - Google Patents

Abstract

Injector with servo valve control with an injector body (20) having a nozzle module (150) with a nozzle body (160) and a nozzle needle (150) having the injection nozzle. The nozzle needle (150) corresponds to a nozzle spring (180); an intermediate plate (50) and a valve plate (60), a high pressure line (30) and a control chamber (190) which is connected via an inlet throttle (130) with the control chamber (190). The latter is connected via a fluid passage (200) to a valve space (210) in which a valve body (220) is in communication with a transmission pin (120) which is connected to an actuator (90) biased by a wave spring (80). connected is. The transmission pin (120) is fitted in the valve body (220) with a small clearance, so that a sealing gap (250) is formed between it and the valve body (220). The latter has bores (230) which connect the valve space (210) with the sealing gap (250). A coupling space (260) is formed between the transmission pin (120) and the valve body (220) which is in communication with the valve space (210) via the sealing gap (250) and the bores (230). The sealing gap (250) is so small that there is fluid communication between the coupling space (260) and the valve space (210) during the time of valve actuation there is no fluid exchange between the coupling space (260) and the valve space (210). A valve seat (290) is provided between the valve body (220) and the intermediate plate (50), and a drain throttle (300) is provided in the transfer pin (120) which communicates with bores (280) in the transfer pin (120) connecting the drain throttle (300) to the valve seat (290).

Description

The present invention relates to an injection valve with servo valve control for the injection of fuel into the combustion chamber of an internal combustion engine according to the preamble of claim 1. Such injectors are typically used in conjunction with a so-called high pressure common rail system. In this case, a piezo element is often used as an actuator, wherein the control of the injection quantity of such common rail injection valves takes place mainly indirectly via a servo valve. This means that the nozzle needle is not directly coupled to the movement of the piezoelectric actuator, but that the piezoelectric actuator in turn actuates a servo valve. The supply of fuel typically occurs under very high pressure via a high pressure port and a high pressure line in the injector body through a valve plate to a throttle plate. A control chamber is connected via an inlet throttle with the high pressure line. In addition, the control chamber is connected via an outlet throttle with a valve chamber. In the lower region, which is the region which faces the combustion chamber, the injection nozzle has a nozzle body and a nozzle needle, the nozzle needle being biased by a nozzle spring in such a way that it exerts a closing force on the nozzle needle. Since the control chamber is connected to the rail via the high-pressure connection, a high pressure prevails in the control chamber when it is not actuated, which corresponds to the pressure in the rail system (rail pressure). This results in an additional hydraulic force, which keeps the nozzle needle in the closed position and thus the openings of the injection valve are closed.

If the piezo actuator is actuated, it actuates the servo valve. As a result, fuel can leave the control chamber via the outlet throttle. As a result, the pressure in the control chamber is lowered and after falling below a certain pressure threshold, the nozzle needle is opened. After a subsequent discharge of the piezoelectric actuator closes the servo valve, the control chamber is refilled via a connection to the high pressure system, so that the pressure in the control room again builds on rail pressure and the nozzle needle closes. The dynamics of the pressure drop or of the pressure build-up in the control chamber and the needle speed during the needle-opening or needle-closing movement are essentially determined by the dimensioning of the inlet and outlet throttles.

In order to ensure a stable operation of a common rail injector with piezoelectric actuator, a play-free coupling between the piezoelectric actuator and the valve body of the servo valve is required. For this purpose, a very accurate temperature compensation of the thermal changes in length in the entire drive chain is required to keep the change in the idle stroke of the piezoelectric actuator within narrow limits. For this purpose, the piezoelectric actuator is usually surrounded by an Invar sleeve, which has a similar thermal expansion behavior as the piezoelectric actuator.

However, it is necessary that a small defined idle stroke of the servo valve is present, so there is a small gap between the servo valve body and the bottom plate of the actuator, since it must be prevented that the servo valve is open when not actuated piezoelectric actuator. Conversely, too large a set idle stroke is disadvantageous, since thereby the required Piezoaktorhub is increased to the same extent and this in turn increases the necessary drive energy accordingly. Overall, this increases the requirements on the constancy of the accuracy of the system even over longer periods.

The use of injectors in the engine provides thermally very complex boundary conditions with different heat sources and heat sinks. In the area of the piezoelectric actuator self-heating plays an important role as a result of electrical losses. In the area of the servo valve, the temperature increase due to the relaxation of the fuel from rail pressure to ambient pressure is a significant source of heat. The installation of the injector in the cylinder head of an engine results in various contact points, such as the combustion chamber seal and the contact of the nozzle tip with the combustion gases heat flows. Another factor to be taken into account on the idle stroke is the verpratzungskraft in the cylinder head dar. This is also subject to great tolerance.

In static injector operation, the resulting thermal expansions can be largely compensated by suitable choice of material and geometry. In dynamic engine operation, as a result of unsteady, inhomogeneous temperature distribution in the components, there is an additional influence on the idle stroke of the piezoactuator. Furthermore, the idle stroke in the injector mode changes due to change in length of the piezoelectric actuator as a result of polarization changes and wear.

Thermally induced changes in length can be largely compensated by a suitable use of different materials. An example is the already mentioned use of actuator housings from Invar, since Invar has a substantially same temperature expansion behavior as the piezoceramic. Ultimately, however, this represents only a basic compensation. Leerhubveränderungen as a result of wear or change in the polarization state are not detected.

To solve this problem exist piezo common rail injectors, which use a hydraulic coupler consisting of a cylinder with a drive piston on the actuator side and a driven piston on the valve side. A disadvantage of this arrangement is that this hydraulic coupler is in the low pressure range. However, to keep such a coupler functioning, a certain pressure level is usually about 10 bar to ensure. In the prior art, this is achieved with a pressure-holding valve.

However, the increasing use of low-boiling fuel components, for example by admixing alcohol with the fuel, jeopardizes the functional capability of corresponding hydraulic coupling elements in the low-pressure region and thus represents a significant functional risk for such concepts.

From the EP 1 389 274 In addition, a directly operated injection valve with a hydraulic coupler is known. However, this has the disadvantage that the actuator is not sufficiently decoupled from the nozzle needle, which also complicates the compensation of wear.

Object of the present invention is therefore to avoid the above-mentioned problems of injectors according to the prior art and to provide an injection valve with servo valve control available, which decoupled the actuator sufficiently from the nozzle needle, on the other hand, by temperature fluctuations and wear Component compensated changes in length during operation of the injector compensated.

This object is solved by the characterizing part of claim 1 and further explained by the teaching of the dependent claims.

Thus, the invention provides an injection valve with servo valve control for injecting fuel into the combustion chamber of an internal combustion engine, wherein the Einsprtizventil having an injector body with an injection nozzle, which in turn includes a nozzle module with a nozzle body and a nozzle needle, wherein the nozzle module facing the combustion chamber Side of the injector body is arranged. The nozzle needle corresponds with a nozzle spring such that it exerts a closing force on the nozzle needle. In the injection valve, a near-intermediate intermediate plate and a immediately adjacent in the nozzle direction valve plate is arranged. The injection valve is also connected to a high-pressure line, via which it is connected to the high-pressure fuel system (common rail). At another point, the high pressure line is connected via an inlet throttle with a control chamber, wherein the control chamber is connected via a fluid passage with a valve chamber, which is formed in the valve plate. Advantageously, in addition, a nozzle orifice is present, which can support the closing of the nozzle needle hydraulically.

In the valve chamber, a valve body is arranged, which is in communication with a transmission pin, which in turn is connected to a biased by a wave spring actuator.

According to the present invention, the transmission pin is now fitted with little play in the valve body, so that a sealing gap is formed between the transmission pin and the valve body. The valve body has holes which connect the valve space with the sealing gap. Between the transmission pin and the valve body in the region of the actuator remote end of the transmission pin, a coupling space is formed, which is connected via the sealing gap and the bore with the valve chamber. The sealing gap is dimensioned so small that on the one hand there is a fluid connection between the coupling space and the valve space, on the other hand during the short time of valve actuation virtually no fluid exchange between the coupling space and the valve space can take place, so that the coupling space does not change in this time. Desweitern a valve seat between the valve body and the intermediate plate is provided and in the transmission pin, a discharge throttle is formed, which is in communication with holes in the transfer pin, which connect the outlet throttle with the valve seat. Thus, the system acts from the holes in the valve body with the sealing gap and the coupling volume as a hydraulic coupler. The flow restrictor integrated in the transfer pin enables a very small volume to be created downstream of the valve seat of the servo valve, which offers advantages in terms of the representation of small hydraulic spray clearances in the case of multiple injections.

Unlike in the prior art, the coupler is in the idle state of the valve under high pressure, so that a lowered boiling point of the fuel, such as by admixture of low-boiling components, such as bioalcohol, has no negative impact. The time in which the valve is actuated, ie in which the actuator deflects and opens the servo valve, wherein the pressure in the valve chamber drops, is so short that in this time no appreciable amount of liquid (fuel) from the coupling volume through the sealing gap and the holes in the valve body can enter the valve space, so that the high pressure is maintained in the hydraulic coupler itself. However, over a longer period of time, pressure equalization across the existing fluid connection may occur across the seal gap between the coupler volume and the valve space, causing length change can be compensated in the valve system in the long term.

According to one embodiment of the invention, the outlet throttle connects the valve chamber with a low-pressure region in the region of the actuator, when the valve body lifts off from the valve seat. As a result, it is possible to avoid cavitation damage in areas subject to high pressure, which adversely affects the high-pressure resistance of these components.

According to a further embodiment of the invention, the valve seat between the valve body and the intermediate plate is formed as a flat seat. In this way, the seat can be inexpensively manufactured together with the production of the high-pressure sealing surface.

It is also advantageous if the transmission pin is guided in the intermediate plate with a small mating game. Thus, the volume flow in the gap is very small in relation to the flow rate through the outlet throttle and thus the disturbing influence negligible.

It is advantageous if the transmission pin is made of hard metal. In this way, a very high rigidity of the transmission pin can be achieved.

According to a further embodiment, a valve spring is arranged in the valve chamber, which acts on the valve body in the direction of the intermediate plate. This ensures that the servo valve is securely closed even in the unpressurized state. The spring force can be very small, since during operation of the injector, the essential closing force for the servo valve results from the pressure in the control chamber.

According to a further embodiment, the actuator has stacked piezo elements (piezostacks) and is designed as a fully active piezo stack which is generally less susceptible to cracking in the interior of the piezo stack sequence, since, in contrast to a non-fully active stack, not only parts of its respective piezoelectric layers of electrical material are covered, but the cover over the entire surface and the contacting takes place in the piezo stack sequence alternately edge side of the stack side. The layers to be contacted differently in each case are alternately insulated on the edge side on this contact side.

The high pressure line is preferably connected via a nozzle orifice to the interior of the nozzle body, which serves for better hydraulic control of the injection valve.

It is also advantageous if the sealing gap between valve pin and valve body is about 1 micron. For the coupling volume, a volume of about 0.5 mm ^{3 has} proved to be advantageous. Both dimensions provide a particularly suitable operation of the injection valve.

The nozzle needle of the injection valve preferably opens inwards, especially in diesel applications, because there the pressures of the fuel are very high and thus a high sealing force acts on the sealing seat of the injection valve. In another reversal of the fuel flow familiar to the person skilled in the art, however, an outwardly opening valve can likewise be realized with the invention, in particular in the case of gasoline injectors.

In another aspect, the actuator may be biased by a wave spring surrounding the actuator to stabilize and at the same time seal the piezoactuator to protect the piezoelectric stack.

An embodiment of the invention is explained in more detail below with reference to the schematic drawings.

• 1 eine Schnittdarstellung eines Inline-Piezo-Common-Rail-Einspritzventils;
• 2 eine Schnittansicht eines oberen Teils eines Einspritzventils, und
• 3 eine Schnittansicht durch die hydraulisch relevanten Komponenten des erfindungsgemäßen Einspritzventils;

Show it:

• 1 a sectional view of an inline piezo common rail injection valve;
• 2 a sectional view of an upper part of an injection valve, and
• 3 a sectional view through the hydraulically relevant components of the injection valve according to the invention;

Elements of the same construction or function are identified across the figures with the same reference numerals.

1 shows the essential part of an injection valve 10 and 2 a sectional view of the upper part of the injection valve 10 , The injection valve 10 has an injector body 20 on. In the injector body 20 is a high pressure line 30 formed in the upper part of the injection valve 10 by means of a high-pressure connection 40 ( 2 ) is connected to a high-pressure fuel system - common rail. Via the high pressure connection 40 A pressurized fuel enters the high pressure line 30 fed. The high pressure line 30 extends substantially in the longitudinal direction through the injector body 20 through an intermediate plate 50 and a valve plate 60 up to a high pressure area 70 which is in 3 can be seen in detail.

Next to the high pressure line 30 is one of a wave feather 80 surrounded actor 90 arranged, via an actuator head plate 100 with the injector 20 connected is. The actor 90 preferably consists of a piezo stack. However, other materials, especially magnetostrictive material, may also be used. About a bottom plate 110 of the actor 90 this is with a transmission pin 120 can be brought into contact, which in the intermediate plate 50 is guided, and acts directly on this. The high pressure line 30 also runs through the intermediate plate 50 and then flows into the valve plate 60 in the range of an inlet throttle 130 and a nozzle orifice 140 , The above-described hydraulically relevant components of the intermediate plate 50 and the valve plate 60 are in 1 not shown, 3 shows this in a detailed representation as a section A of 1 ,

In the lower, the combustion chamber facing part of the injector body 20 , there is a nozzle module 150 , which consists of a nozzle body 160 , a nozzle needle 170 and a nozzle spring 180 composed.

3 shows the area of the intermediate plate 50 and the valve plate 60 and the hydraulically relevant components in more detail. About the high pressure line 30 the fuel enters the system and passes through the inlet throttle 130 in a control room 190 , In parallel, fuel passes through the nozzle orifice 140 in the inner area of the nozzle module 150 at the control room 190 past.

The control room 190 again with a fluid passage 200 in connection, which in the valve plate 60 is trained. The fluid passage 200 opens into a valve chamber 210 in the valve plate 60 , In the valve room 210 there is a valve body 220 a servo valve, which is acted upon in its lower region by a valve spring (not shown) which has an upward force on the valve body 220 exerts, so that the servo valve is securely closed even in the unpressurized state. The spring force can be very small, since during operation of the injection valve 10 the essential closing force for the servo valve from the pressure in the control room 190 and the valve room 210 results.

The valve body 220 has holes 230 on that in a central hole 240 in the valve body 220 lead. In this is with very little play the transmission pin 120 led, who with the actor 90 over the Aktorbodenplatte 110 communicates. Between the transmission pin 120 and the wall of the valve body 220 there is a narrow sealing gap 250 over which the holes 230 in fluid communication with a very small gap, the coupling space 260 , stand. Thus, the known from the prior art, vacancy-laden mechanical coupling between the Piezoaktorhub and the servo valve movement is replaced by a hydraulic coupling with a self-integrated in the servo valve body clearance compensation. Unlike in the prior art known in the servo valve body integrated clearance compensation high pressure, ie the rail pressure, so that the above-mentioned boiling problems can not occur.

In the upper, the actor 90 facing portion of the transmission pin 120 is in the transmission pin 120 a central hole 270 provided over which the central bore 270 a hydraulic connection between a valve seat 290 of the valve body 220 and an outlet throttle 300 manufactures. The outlet throttle 300 is in the actor 90 facing portion of the transmission pin 120 configured to provide fluid communication between the central bore 270 in the transfer 120 and a low pressure area 310 forms. Furthermore, in the transmission pin 120 a Züufbohrung 330 formed radially in the transmission pin 120 is inserted and in the area of Vetntilsitzes 290 in the transmission pin 120 is provided. Via the inlet bore 330, the hydraulic connection between the valve seat 290 and the outlet throttle 300 over the central hole 270 in the transmission pin 120 , The valve body 220 forms with its actuator facing the end of the valve seat 290 with the intermediate plate 50 , The in the transmission pin 120 trained outlet throttle 300 flows into the near-actuated area of the transmission pin 120 in the low pressure area 310 ,

The function is in detail the following:

The piezo actuator 90 , which is preferably designed as a fully active piezo stack, is in the injector body 20 integrated so that it is up directly in the injector body 20 supported. The piezo actuator 90 is through the wave spring 80 against the fuel-carrying areas in the injection valve 10 sealed, with the wave spring 80 at the same time for the bias of the actuator 90 provides. Unlike the prior art, therefore, not the entire actuator space is sealed off from the fuel, but only the area of the actuator 90 This is possible because the use of an Invar sleeve for temperature compensation can be dispensed with. As a result, the low-pressure volume in the area of the actuator increases 90 by at least an order of magnitude, which is why the pressure pulses which are generated when the servo valve is opened are reduced to a similar extent.

The stroke of the piezo actuator 90 is by means of the transmission pin 120 , which with very little play in the central hole 240 is fitted in the servo valve body, on the servo valve body 220 transfer. At about half the height of the servo valve body 220 are the two radial holes 230 which the valve space 210 and with this the control room 190 with the sealing gap 250 between the transmission pin 120 and the valve body 220 connect. In the closed state of the servo valve prevails in the valve chamber 210 and the control room 190 Rail pressure, which through the radial bores 230 in the sealing gap 250 is transmitted. This pressure gets into the very small paddock 260 transferred, which at the, the piezoelectric actuator 90 facing away from the transmission pin 120 located. This pressure causes the transmission pin 120 is always pressed outwards until it is to rest against the Aktorbodenplatte 110 comes. As a result, a play-free contact between the piezoelectric actuator 90 and the servo valve guaranteed. Movements with very low dynamics such as temperature expansion and wear can be achieved by changing the coupling space height 320 be compensated. For highly dynamic movements, as the piezobody movement is, the sealing gap is 250 almost dense and thus the coupler very stiff.

Will the piezo actuator 90 operated, the valve body 220 over the transmission pin 120 pressed down so that the valve seat 290 between the valve body 220 and the intermediate plate opens. Via the inlet bore 330, the central bore 240 and the outlet throttle 300 the fuel escapes upwards, causing the pressure in the valve chamber 210 decreases. Thus, the servo valve must be kept open only against the valve spring force and a low hydraulic force.

Due to the pressure drop in the valve chamber 210 and over the fluid passage 200 in the control room 190 fuel flows out of the valve chamber 210 in the low pressure area 310 , Because of the inlet throttle 130 less fuel flows through than through the outlet throttle 300 flows out, the pressure in the valve chamber decreases 210 and in the control room 190 from. This reduces the on the nozzle needle 170 acting hydraulic closing force in the control room 190 , After falling below a certain pressure threshold opens the nozzle needle 150 and the injection starts.

Will the piezo actuator 90 Relaxed, the servo valve closes again, turning the valve body 220 against the intermediate plate 50 is pressed and the valve seat 290 closes and seals. The pressure in the valve chamber 210 rises again, as does the pressure in the control room 190 so that as a result the nozzle needle 150 pushed back down into her seat. The injection valve is closed.

The example described shows an inwardly opening injection valve. Of course, with appropriate force reversal, the use of an outwardly opening valve is encompassed by the invention.

Thus the coupling over the coupling space 260 works correctly, the sealing gap needs 250 are so small that even at high rail pressure only a sufficiently small fuel leakage is possible and at the same time no jamming of the transmission pins 120 in the valve body 220 he follows. Typically, the sealing gap 250 less than 1 micron, with the volume in the Kopperlraum 260 with 0.5 mm ^{3 is} sufficiently large to realize a very rigid drive.

As a result, the problematic, known from the prior art, Leerhubbehaftete mechanical coupling of the piezoelectric actuator with the servo valve body by a hydraulic coupling with a built-in servo valve clearance compensation and one in the transmission pin 120 replaces integrated drain throttle. As a result, the compensation of changes in length due to temperature effects, wear at contact points in the drive is improved, as well as the compensation of changes in length of the piezoelectric actuator itself, for example as a result of changes in the polarization state. The reduction of the pressure pulses in the actuator chamber and thus the reduction of the parasitic effects on the sensor signal of the piezoelectric actuator are achieved inter alia by the enlargement of the low-pressure region. In the region of - not shown - electrical contacts in the upper part of the injector vibrations can be reduced if the piezo head plate rests stiffly in the injector body. Through this coupling, which also works for lighter boiling fuels, eliminates the costly adjustment process for the idle stroke in injector assembly. The cavitation effects in the high-pressure-loaded area are eliminated, thus improving the high-pressure capability. At the same time, the volume downstream of the servo valve can be minimized and associated with it, the achievable minimum spray intervals can be reduced with multiple injection. Likewise, the manufacturing costs are reduced. During operation, the drive energy for the piezoelectric actuator is reduced because the idle stroke is eliminated. Due to the increased accuracy, the injection quantities variations can be reduced as a function of the Verpratzungskraft in the cylinder head and the injection quantity stability can be improved in dynamic engine operation. The control chamber pressure can be fed back to the piezoelectric actuator to derive sensor signals, which are used to control the injection quantities. Due to the increased accuracy of the injection quantity variations can be reduced depending on the Verpratzungskraft in the cylinder head and the injection quantity stability can be improved in dynamic engine operation.

LIST OF REFERENCE NUMBERS

10

Injector

20

injector

30

High-pressure line

40

High pressure port

50

intermediate plate

60

valve plate

70

High pressure area

80

wave spring

90

actuator

100

Aktorkopfplatte

110

actuator base plate

120

spin transfer

130

inlet throttle

140

nozzle cover

150

nozzle module

160

nozzle body

170

nozzle needle

180

nozzle spring

190

control room

200

Fluid passage

210

valve chamber

220

valve body

230

drilling

240

central hole

250

sealing gap

260

coupling space

270

central hole

280

radial bore

290

valve seat

300

outlet throttle

310

Low pressure area

320

Coupling chamber height

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1389274 [0010]

Claims (12)

Injector with servo valve control for injecting fuel into the combustion chamber of an internal combustion engine, comprising an injector body (20) having a nozzle module (150) with a nozzle body (160) and a nozzle needle (170), wherein the nozzle module (150) on the combustion chamber facing the injector body (20) is arranged and the nozzle needle (170) with a nozzle spring (180) corresponds, which is arranged so that it exerts a closing force on the nozzle needle (170), a Aktornah arranged intermediate plate (50) and a to this in the direction of the nozzle body (160) subsequent valve plate (60), a high pressure line (30) and a control chamber (190) having a connection to the high pressure fuel system and which is connected via an inlet throttle (130) with the control chamber (190) , wherein the control chamber (190) via a fluid passage (200) with a valve chamber (210) is connected, which in the valve plate (60) au in which valve space (210) a valve body (220) is arranged, wherein the valve body (220) communicates with a transmission pin (120), which in turn is connected to an actuator (90) biased by a wave spring (80) characterized in that the transfer pin (120) is fitted into the valve body (220) with a small clearance such that a sealing gap (250) is formed between the transfer pin (120) and the valve body (220), and the valve body (220) Holes (230) which connect the valve space (220) with the sealing gap (250), and wherein a coupling space (260) between the transmission pin (120) and the valve body (220) in the region of the actuator remote end of the transmission pin (120) is, which is connected via the sealing gap (250) and the bores (230) with the valve chamber (210), and wherein the sealing gap (250) is dimensioned so small that on the one hand a fluid connection between the coupling space (260) and the vent ilraum (210), on the other hand during the short time of valve actuation virtually no fluid exchange between coupling space (260) and the valve space (210) can take place, so that the coupling space (260) does not change in this time that a valve seat (290) is provided between the valve body (220) and the intermediate plate (50) and in that an outlet throttle (300) is formed in the transmission pin (120) which communicates with bores (270; 330) in the transmission pin (120) connecting the Connect the outlet throttle (300) to the valve seat (290). Injector after Claim 1 , characterized in that the outlet throttle (300) connects the valve chamber (210) with a low pressure region (310) in the region of the actuator (90) when the valve body (220) lifts off the valve seat (290). Injection valve according to one of the preceding claims, characterized in that the valve seat (290) is formed between the valve body (220) and the intermediate plate (50) as a flat seat. Injection valve according to one of the preceding claims, characterized in that the transmission pin (120) is guided in the intermediate plate (50) with a small mating clearance. Injection valve according to one of the preceding claims, characterized in that the transmission pin (120) is made of hard metal. Injection valve according to one of the preceding claims, characterized in that in the valve chamber (210) a valve spring is arranged, which acts on the valve body (220) in the direction of the intermediate plate (50). Injection valve according to one of the preceding claims, characterized in that the actuator (90) has piezo elements, preferably in the form of a fully active piezo stack. Injection valve according to one of the preceding claims, characterized in that the high-pressure line (30) via a nozzle orifice (140) with the interior of the nozzle body (160) is connected. Injection valve according to one of the preceding claims, characterized in that the sealing gap (250) between the transmission pin (120) and the valve body (220) is about 1 micron to 10 microns. Injection valve according to one of the preceding claims, characterized in that the coupling space (260) has a volume of less than 1.5 mm ³ . Injection valve according to one of the preceding claims, characterized in that the nozzle needle (170) opens inwards. Injection valve according to one of the preceding claims, characterized in that the actuator (90) by a wave spring (80) is biased and sealed at the same time.

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