EP1929149A1

EP1929149A1 - Injection nozzle

Info

Publication number: EP1929149A1
Application number: EP06792593A
Authority: EP
Inventors: Hans-Christoph Magel
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2005-08-30
Filing date: 2006-07-28
Publication date: 2008-06-11
Anticipated expiration: 2026-07-28
Also published as: WO2007025815A1; EP1929149B1; DE502006004022D1; DE102005040912A1

Abstract

The invention relates to an injection nozzle (1) for an internal combustion engine, especially of a motor vehicle. Said injection nozzle (1) comprises a nozzle needle (3) which is mounted in a vertically adjustable manner in a nozzle member (2) to control injection of fuel that is under injection pressure through at least one spray port (5), and a coupling piston assembly (21) that is drivingly connected to an actuator (20) and is provided with a coupling surface (22). The nozzle needle (3) or a bunch of needles (10) encompassing the nozzle needle (3) are/is provided with a control surface (13) that is hydraulically coupled to the coupling surface (22). In order to be able to design the actuator (20) shorter in an axial direction, an entraining piston (26) is supplied which is provided with an entraining surface (27) that is hydraulically coupled to the control surface (13) while an entraining coupling (28) is supplied which transmits tractive forces from the coupling piston assembly (21) to the entraining piston (26) and entrains the entraining piston (26) only once a shifting lift (29) has been reached when the actuator (20) is lifted in an opening manner.

Description

injection

State of the art

The present invention relates to an injection nozzle for an internal combustion engine, in particular of a motor vehicle, having the features of the preamble of claim 1.

From EP 1 174 615 A2, an injection nozzle of this type is known, which has a nozzle needle which is mounted so that it can be adjusted in terms of stroke in a nozzle body and serves to control the injection of fuel under injection pressure through at least one pointed hole. The injector also has a coupler piston, which with a

Actuator is drivingly connected and having a coupler surface, while the nozzle needle is equipped with a control surface. In the known injection nozzle, the nozzle needle is arranged adjustable in height relative to the coupler piston and coupled in a closed position of the nozzle needle via a driver coupling for tensile force transmission to the coupler piston. In addition, the control surface is hydraulically coupled to the coupler face. The known injection nozzle realizes a two-phase Öffhungskinematik for the nozzle needle. The actuator is operated inversely and is energized or tensioned for the closed position of the nozzle needle. To open the nozzle needle, the actuator is discharged or expanded, whereby it pulls the thus drive-connected coupler piston from at least one injection hole. About the driver coupling thereby inevitably the nozzle needle is pulled out of its seat. During this first phase of the opening kinematics of the coupler piston is mechanically connected via the driver coupling mechanically connected to the nozzle needle, whereby the Öffhungshub the actuator is transmitted directly, ie without translation or reduction to the nozzle needle. At the same time, the opening stroke of the Kopplerkolbens the pressure in a limited by the control surface and the coupler face control chamber lowered, while in addition to a seat surface of the nozzle needle, which is removed when opening the needle seat, an injection pressure builds up. As soon as the hydraulic opening forces acting on the nozzle needle predominate, the nozzle needle is accelerated in the opening direction relative to the coupler piston.

Nozzle needle and coupler piston are then hydraulically coupled to each other, at the same time a determined by the coupler surface and the control surface gear ratio is effective. During this second phase of the opening kinematics, the nozzle needle can perform a relatively large opening stroke in a short time. Overall, such a two-stage direct needle control is beneficial for achieving high

Injection volumes with short injection times.

Due to the mechanical entrainment coupling between the coupler piston and the nozzle needle during the first phase of the opening kinematics of the Öffhungshub the nozzle needle is the same size as the opening stroke of the actuator. To achieve a sufficient needle lift, the actuator must accordingly build comparatively large in the axial direction. For the installation of injectors is on the internal combustion engine regularly little space available, which complicates the realization of the known construction.

Advantages of the invention

The injection nozzle according to the invention with the features of claim 1 has the advantage that already in the first phase of the Öffhungskinematik a translation between the strokes of actuator and nozzle needle is possible. As a result, the axial length of the actuator can be reduced accordingly, whereby the

Injector overall compact builds. This is achieved by the fact that the coupler piston or a coupler piston assembly cooperates via a driver coupling with a driver piston, in such a way that the Kopplerkolbenanordnung entrains the driver piston only after a predetermined shift stroke in a Öffhungshub of the actuator. This driver piston is with a

Driver surface equipped, which is also hydraulically coupled to the control surface. By this construction it is achieved that during a first phase of the Öffhungskinematik there is a hydraulic coupling between the Kopplerkolbenanordnung and the nozzle needle, which operates with a first gear ratio. This first transmission ratio is in this case by the coupler surface in relation to the control surface Are defined. This first gear ratio can be selected specifically so that in the nozzle needle a sufficiently large Öflhungskraft can be initiated. When the switching stroke is reached, a second phase of the opening kinematics begins. The forced coupling between the coupler piston arrangement and the driver piston achieved with the aid of the driver coupling results in a significant increase in the event of a further opening stroke of the actuator

Change of hydraulic ratio between actuator stroke and nozzle needle stroke. Because in the second phase, the driver surface is added to the coupler surface, whereby the new or second gear ratio is defined by the sum of coupler surface and driver surface in relation to the control surface. By appropriate dimensioning of the driving surface, the nozzle needle can be moved during the second phase of the Öffhungskinematik with reduced Öffhungskraft with a significantly increased Öffhungsgeschwindigkeit. As a result, relatively large injection quantities can be realized at relatively short injection times.

According to an advantageous embodiment, the Kopplerkolbenanordnung comprises a drivingly connected to the actuator first coupler piston and coupled via the driver coupling with the driver piston from the switching stroke for tensile force transmission second coupler piston, wherein the two coupler pistons coaxially arranged one inside the other and stroke-adjustable and hydraulically coupled to each other are drive-coupled. The built from two coupler pistons

Coupling piston arrangement allows compensation of thermal expansion and manufacturing tolerances. This results in increased reliability and simplified manufacturability for the injection nozzle.

Preferably, the driver piston can now be mounted to be adjustable in stroke on the second coupler piston and, in particular, can be biased into a starting position by means of a return spring supported on the first coupler piston. In this way, the injector receives in the field of driver coupling a particularly simple structure that can be implemented comparatively inexpensive.

In another advantageous embodiment, in a control path that hydraulically connects the coupler face to the control face, a control valve configured to provide greater flow resistance for a hydraulic flow oriented from the control face to the coupler face than for one from the coupler face to the control surface oriented hydraulic flow. This construction - A -

causes the Öffhungsbewegung the nozzle needle is braked or damped at least during the second phase, since the Öfmungsvorgang the greater flow resistance is effective. This is to achieve extremely short injection times with small injection quantities of advantage, since the nozzle needle then performs only a relatively small stroke during these short Öffungsungszeiten. In addition, the proposed construction causes the nozzle needle can be closed extremely quickly, since during the closing movement of the smaller flow resistance is active. Extremely short closing times allow injection times and injection quantities to be set with increased accuracy.

Further important features and advantages of the injection nozzle according to the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

drawings

Embodiments of the injection nozzle according to the invention are illustrated in the drawings and are explained in more detail below, wherein like reference numerals refer to the same or similar or functionally identical components. Show, in each case schematically,

1 is a greatly simplified, schematic longitudinal section through an injection nozzle,

Fig. 2 is a view as in Fig. 1, but in another embodiment.

Description of the embodiments

According to FIGS. 1 and 2, an injection nozzle 1 comprises a nozzle body 2, in which a nozzle needle 3 is mounted in a stroke-adjustable manner. The injection nozzle 1 is used for installation in an internal combustion engine, not shown, which is arranged in particular in a vehicle. The

Injector 1 is connected in the assembled state to a high-pressure fuel line 4. If several injectors are connected to the same high-pressure fuel line 4, it is a so-called "common rail system". The nozzle needle 3 is used to control the injection of standing under injection pressure fuel through at least one injection hole 5 in an injection chamber 6. For this purpose, the nozzle needle 3 cooperates with a needle seat 7. When the nozzle needle 3 is seated in its needle seat 7, the nozzle needle 3 is in its closed position and separates the at least one injection hole 5 from a fuel supply 8. This fuel supply 8 is connected via a corresponding connecting line 9 to the fuel high pressure line 4.

The nozzle needle 3 is usually a component of a needle assembly 10 which is stroke-adjustable as a unit. For example, this needle assembly 10 consists of the nozzle needle 3, a control piston 11 and a support plate 12. At least two of the individual components of the needle assembly 10 may be loosely attached to each other or be made of one piece.

The needle needle 3 and the needle assembly 10 has a control surface 13 which has a

Control chamber 14 axially limited. For the radial limitation of the control chamber 14, a control chamber sleeve 15 is provided, which is mounted axially adjustable on the nozzle needle 3 and the needle assembly 10. In the present case, the control surface 13 and the control chamber sleeve 15 are formed or arranged on the control piston 11. Furthermore, a closing pressure spring 16 is provided, which drives the nozzle needle 3 in its closed position. For this purpose, the closing compression spring 16 is supported in the axial direction on the one hand on the control chamber sleeve 15 and on the other hand on the nozzle needle 3 or on the needle assembly 10, here on the support plate 12. The control chamber sleeve 15 is thereby firmly pressed against an intermediate plate 17, whereby in response to the nozzle needle 3 is driven in the direction of its seat 7.

The aforementioned intermediate plate 17 is a part of the nozzle body 2 and separates in this a needle portion 18, in which the nozzle needle 3 and the needle assembly 10 is arranged, of an actuator portion 19, in which an actuator 20 is arranged. The fuel supply 8 is passed through the intermediate plate 17 in a suitable manner, for. B. by means of at least one unspecified bore. The aforementioned actuator 20, in particular a piezoactuator, is drive-connected to a coupler piston arrangement 21. This coupler piston assembly 21 is equipped with a coupler face 22 which axially bounds a translator pocket 23. Via a hydraulic control path 24, for example in the form of a control channel 25 through the intermediate plate 17 is passed, the booster chamber 23 and the control chamber 14 are hydraulically coupled together. Accordingly, the coupler surface 22 and the control surface 13 are hydraulically coupled to each other.

In addition, the injection nozzle 1 comprises a driver piston 26 which is within the

Nozzle body 2 is arranged adjustable in stroke and has a driver surface 27. The driver surface 27 also limits the booster chamber 23 axially and is therefore hydraulically coupled to the control surface 13. Furthermore, a driver coupling 28 is provided. This driver coupling 28 is configured such that it transfers tensile forces from the coupler piston arrangement 21 to the driver piston 26 only when switching stroke 29 of the actuator 20, in which the coupler piston assembly 21 moves away from the at least one injection hole 5. As a result, takes the coupler piston assembly 21 at a beyond the shift stroke 29 Aktorhub the driver piston 26 with.

In the preferred embodiment shown here, the coupler piston assembly 21 comprises a first coupler piston 30 and a second coupler piston 31. The two coupler pistons 30, 31 are arranged coaxially with one another and mounted to one another in a stroke-adjustable manner. The first coupler piston 30 is drive connected to the actuator 20, so that a stroke of the actuator 20 inevitably the first coupler piston

30 to carry out the identical hub entrains. In contrast to this, the second coupler piston 31 can be coupled via the driver coupling 28 to the driver piston 26, such that the second coupler piston 31 inevitably entrains the driver piston 26 from the switching stroke 29. Furthermore, the two coupler pistons 30, 31 are drive-hydraulically coupled with each other, so that a stroke of the first coupler piston 30 leads to a corresponding stroke of the second coupler piston 31. For this purpose, the two coupler pistons 30, 31 enclose a coupler space 32, in which the hydraulic coupling of the two coupler pistons 30, 31 takes place. The first coupler piston 30 is designed as a sleeve into which the second coupler piston 31 is inserted in the manner of a plunger. The hydraulic volume enclosed in the coupler space 32 forces the hydraulic coupling of the two coupler pistons 30, 31. In the coupler space 32, a stop spring 33 is arranged, which absorbs the forces occurring in the event of a collision of the two coupler pistons 30, 31. By virtue of the hydraulic volume enclosed in the coupler space 32, the coupler piston arrangement 21 can compensate for thermally induced expansion effects as well as manufacturing tolerances of the coupler pistons 30, 31. In the embodiments shown here, the driving piston 26 is arranged coaxially with the second coupling piston 31 and mounted on this hubverstellbar. Furthermore, the driving piston 26 is biased in a starting position shown here. For this purpose, a return spring 34 is provided, which is supported on the one hand on the driving piston 26 and on the other hand on the first coupler piston 30. The aforementioned starting position of the driving piston 26 is defined here by at least one spacer element 35. About the at least one spacer element 35 of the driver piston 26 is axially supported in its initial position on the intermediate plate 17.

The translator space 23 is bounded radially by a translator space sleeve 36. The compiler space sleeve is preferably arranged coaxially to the driving piston 26 and mounted on this hubverstellbar. Furthermore, an opening compression spring 37 is expediently provided which is axially supported on the one hand on the translator chamber sleeve 36 and on the other hand on the first coupler piston 30. As a result, the opening pressure spring 37 presses the

Translator space sleeve 36 axially to the intermediate plate 17 at.

The driver coupling 28 operates here with an effective in the pulling direction positive engagement, via which the driver piston 26 and the coupler piston assembly 21 and the second coupler piston 31 are in an opening stroke of the actuator 20 from the shift stroke 29 with each other. For this purpose, the driver coupling 28 is provided with a step 38 which projects radially from the coupler piston assembly 21 and from the second coupler piston 31. This stage 38 is suitably made in one piece together with the second coupler piston 31. Likewise, it is in principle possible, this stage 38 by a separate component, for. B. in the form of a disc on the second

Coupling piston 31 to attach. This step 38 engages behind the driver piston 26 on a side facing away from the actuator 20 side. The step 28 thus engages behind the driving piston 26 on its driver surface 27 or in the booster chamber 23.

The embodiment of the injection nozzle 1 shown in FIG. 2 differs from that in FIG

Fig. 1 shown by the fact that in addition a control valve 39 is arranged in the control path 27. This control valve 39 is designed so that it is opposite to a hydraulic flow oriented by the control surface 13 to the coupler surface 22 a greater flow resistance than a hydraulic flow, which is opposite, that is oriented from the coupler surface 22 to the control surface 13. This results for the Nozzle needle 3 a Öffhungsbewegung which is damped compared to the closing movement. Preferably, the control valve 39 is designed as a check valve, which has a valve body 40 which cooperates with a valve spring 41 and with a valve seat 42. The valve spring 41 presses the valve body 40 against the valve seat 42. The valve seat 42 is on one of the control surface 13 facing side of

Intermediate plate 17 is formed and arranged so that the control valve 39 controls the control channel 25 of the intermediate plate 17. The valve body 40 and the valve spring 41 are accordingly arranged in the control chamber 14. Furthermore, a bypass 43 is provided which bypasses the valve body 40 seated in the valve seat 42. In the present case, the bypass 43 is formed in the valve body 40 itself or passed therethrough. The valve spring 41 is supported on the one hand on the valve body 40 and on the other hand on the nozzle needle 3 and the needle assembly 10 from.

The injection nozzle 1 according to the invention operates as follows:

In the initial state shown, the nozzle needle 3 is in its closed position and separates the at least one spray hole 5 from the fuel supply 8, so that no injection takes place. The driver piston 26 is in its initial position in which it is supported by the return spring 34 via the at least one spacer element 35 on the intermediate plate 17. In the control room 14, in the translator room 23 and in

Coupler space 32 prevails as in the fuel supply 8 of the respective desired injection pressure. This is achieved for example by targeted leaks or by suitable throttled connection paths. In the initial state, the inversely operated actuator 20 is energized or charged, whereby it has its maximum longitudinal extent. Corresponding electrical connections of the actuator 20 are designated by 44 in the figures.

The actuator area 19, in which not only the actuator 20 but also the coupler piston arrangement 21, ie the two coupler pistons 30 and 31, and the driver piston 26 and the translator space sleeve 36 are arranged, the injection pressure also prevails, so that said components are arranged quasi "floating" The same applies to the nozzle needle 3 and the needle assembly 10 and the control chamber sleeve 15, the

Needle area 18 are arranged floating in the fuel.

In order to carry out a fuel injection, the actuator 20 is now discharged or expanded, as a result of which its length is reduced. In this case, the end of the actuator 20 connected to the first coupler piston 30 leads from the at least one injection hole 5 directed Öffhungshub through. This Aktorhub the first coupler piston 30 inevitably follows. Likewise, the second coupler piston 31 via the hydraulic coupling follows the first coupler piston 30. This Öfmungsbewegung is supported by the opening pressure spring 37. As a result of the opening stroke of the second coupler piston 31, the volume in the booster chamber 23 increases, as a result of which the pressure in the booster chamber 23 drops. This pressure drop propagates into the control chamber 14 and reduces at the control surface 13, the effective pressure in the closing direction. As a result, prevail at the nozzle needle 3, the Öfmungsrichtung effective forces, whereby the nozzle needle 3 is lifted from the needle seat 7. During this first phase of the opening kinematics, the second coupler piston 31 is not yet engaged with the driver piston 26 via the driver coupling 28. Consequently, the second coupler piston 31 still performs its opening stroke independently of the driving piston 26, which thus remains in its initial position. The driver piston 26 is biased by the return spring 34 in its initial position and accordingly can slide outside on the second coupler piston 31, while this performs its opening stroke. In this first phase, a hydraulic connection with a first hydraulic transmission ratio is effective between the coupler piston assembly 21 and the nozzle needle 3. This first gear ratio is determined by the ratio of the coupler surface 22 to the control surface 13. This first gear ratio is suitably chosen so that the nozzle needle 3 can be pulled out of its needle seat 7 with a sufficiently large force.

Upon reaching the switching stroke 29, it then comes to the positive engagement between the second coupling piston 31 and driving piston 26 via the driver coupling 28. In a further opening stroke of the actuator 20 is then a second phase of the

Opening kinematics before, in which the second coupler piston 31 inevitably entrains the driver piston 6 so that it performs the same stroke as the second coupler piston 31. Consequently, there is then a hydraulic coupling between the Aktorhub and the Nadelhub, which has a second gear ratio. This second transmission ratio is characterized by the sum of the coupler surface 22 and the

Mitnehmerfläche 27 determined in relation to the unchanged control surface 13. This second gear ratio is suitably chosen so that the nozzle needle 3 results in the highest possible opening speed. The switching stroke 29 can be selected, for example, so that the nozzle needle 3 is safely led out on reaching the switching stroke 29 from the so-called "seat throttling". To end the injection process, the actuator 20 is recharged or energized, causing it to expand again. As a result, there is an increase in pressure in the booster chamber 23 and an effective pressure in the closing direction on the control surface 13. Furthermore, the closing movement of the nozzle needle 3 by the

Closing pressure spring 16 supported. Until the switching stroke 29 is reached, the second transmission ratio is present during the closing movement. Upon reaching the shift stroke 29, the driver piston 26 reaches its initial position and stops, while the second coupler piston 31 moves further in the closing direction. Consequently, then there is the first gear ratio.

In the embodiment shown in Fig. 2, the opening operation differs from the closing operation. During the opening process prevails in the control chamber 14 relative to the booster chamber 23, an overpressure and the valve body 40 is seated in the valve seat 42, so that the flow resistance of the control path 24 is determined by the bypass 43. Of the

Bypass 43 is sized so that there is a certain damping effect. That is, the pressure drop in the booster chamber 23 caused by the opening stroke of the actuator 20 or of the second coupler piston 31 can only propagate into the control chamber 14 with a delay. Since this damping depends on the volume flow, it shows its effect mainly in the second phase of the kinematics. In the episode is the

Opening speed of the nozzle needle 3, at least in the second phase of Öffϊhungskinematik smaller than it could be absent control valve 39.

When closing the nozzle needle 3, however, prevails in the interrupter space 23 relative to the control chamber 14, an overpressure, whereby the valve body 40 is lifted against the valve spring 41 from the valve seat 42, which opens an additional flow cross-section. As a result, the pressure balance between the translator 23 and the control room 14 can be done faster. The effective pressure in the closing direction can thus build up particularly quickly on the control surface 13. As a result, the nozzle needle 3 can reach very high closing speeds. The control path 24 is for the

Closing movement virtually undamped. LIST OF REFERENCE NUMBERS

1 injector

2 nozzle body

3 nozzle needle

4 high-pressure fuel line

5 injection hole

6 injection space

7 needle seat

8 fuel supply

9 connection line

10 needle bandage

11 control piston

12 support piston

13 control surface

14 control room

15 control chamber sleeve

16 closing pressure spring

17 intermediate plate

18 needle area

19 Actuator area

20 actor

21 coupler piston assembly

22 coupler surface

23 Translator room

24 control path

25 control channel

26 driving piston

27 driving surface

28 driver coupling

29 switching stroke 30 first coupler piston

31 second coupler piston

32 coupler room

33 stop spring

34 return spring

35 spacer

36 Translator space sleeve

37 opening pressure spring

38 level

39 control valve

40 valve body

41 valve spring

42 valve seat

43 Bypass

44 electrical connection

Claims

claims

1. Injection nozzle for an internal combustion engine, in particular of a motor vehicle, - with a nozzle body (2) adjustable in height mounted nozzle needle (3) for

Controlling the injection of fuel under injection pressure through at least one injection port (5), with a coupler piston assembly (21) drivingly connected to an actuator (20) and having a coupler surface (22), the injector needle (3) or one of Needle needle (3) having Nadelverband

(10) a control surface (13) which is hydraulically coupled to the coupler surface (22), characterized in that a driver piston (26) is provided which has a driver surface (27) which is hydraulically coupled to the control surface (13) is that a driver coupling (28) is provided, which transmits in a Öffhungshub of the actuator (20) only from a switching stroke (29) tensile forces from the coupler piston assembly (21) on the driver piston (26) and entrains the driver piston (26).

2. Injection nozzle according to claim 1, characterized in that the driver coupling (28) couples the coupler piston arrangement (21) with the driver piston (26) via an effective in the pulling direction positive locking, the Öffhungshub of the actuator (20) from a switching stroke (29) in Intervention is.

3. Injection nozzle according to claim 1 or 2, characterized in that the driver coupling (28) has a step (38) which projects radially from the coupler piston assembly (21) and the driving piston (26) at one of the

Actuator (20) facing away from behind.

4. Injection nozzle according to one of claims 1 to 3, characterized in that - the coupler piston assembly (21) has a first coupler piston (30) which is drivingly connected to the actuator (20), that the coupler piston assembly (21) has a second coupler piston (31 ), which via the driver coupling (28) with the driver piston (26) from the

Switching stroke (29) is coupled to the traction transfer, - that the two coupler pistons (30, 31) coaxially arranged one inside the other and are Hubverstellbar each other, that the two coupler pistons (30, 31) are hydraulically coupled to each other drive.

5. Injection nozzle according to claim 4, characterized in that the two coupler pistons (30, 31) in a coupler space (32) which is enclosed by the two coupler pistons (30, 31) are hydraulically coupled to each other driven, and / or - that of a coupler piston (30) forms a sleeve into which the other

Dips in the coupler piston (31), and / or in that a stop spring (33) is arranged in the coupler space (32).

6. Injection nozzle according to claim 4 or 5, characterized in that the driver piston (26) on the second coupler piston (31) is mounted adjustable in stroke, and / or that the driver piston (26) by means of a return spring (34) is biased in an initial position, and /or that the restoring spring (34) is supported on the one hand on the driver piston (26) and on the other hand on the first coupler piston (30) or on the actuator (20), and / or that the driver piston (26) in its initial position via at least one spacer element (35) on a a translator space (23) axially delimiting intermediate plate (17) is supported.

7. Injection nozzle according to one of claims 1 to 6, characterized in that the coupler surface (22) and the driver surface (27) axially limit a booster chamber (23) which is radially bounded by a Übersetzungserraumhülse (36) on the driver piston (26 ) is mounted adjustable in stroke, and / or that the Übersetzungsraumraumhülse (36) by means of a Öflhungsdruckfeder (37) against a the translator (23) axially delimiting intermediate plate (17) of the nozzle body (2) is pressed, and / or - that the Öffiiungsdruckfeder (37 ) is supported on the one hand on the Übersetzungsraumraumhülse (36) and on the other hand on the first coupler piston (30) or on the actuator (20).

8. Injection nozzle according to one of claims 1 to 7, characterized in that in a coupler surface (22) with the control surface (13) hydraulically connecting the control path (24), a control valve (39) is arranged, for one of the control surface (13 ) to the coupler surface (22) oriented hydraulic flow provides a greater flow resistance than for one of the coupler surface (22) to the control surface (13) oriented hydraulic flow.

9. Injection nozzle according to claim 8, characterized in that the control valve (39) is designed as a check valve whose valve body (40) is pressed with a valve spring (41) in the direction of the coupler surface (22) in a valve seat (42).

10. Injection nozzle according to claim 9, characterized in that a seated in the valve seat (42) valve body (40) bypass (43) is provided, and / or in that the bypass (43) is felt through the valve body (40), and / or that the valve seat (42) is formed on a side of the intermediate plate (17) facing the control surface (13) which delimits one of the coupling surface (22) Translator compartment (23) of a control surface (13) limited by the control chamber (14) separates and a the translator compartment (23) with the control chamber (14) connecting, controlled by the control valve (39) control channel (25).