EP1151192B1 - Fuel injection valve for internal combustion engines - Google Patents

Description

State of the art

The invention is based on a fuel injection valve for Internal combustion engine according to the preamble of claim 1 out. Such from DE 196 23 211 A1 known fuel injection valve has a valve body in which in a bore a piston-shaped, against the force of a Closing spring axially movable valve member is arranged. At the combustion chamber end, the valve member goes into a Closing head over, which is guided in the bore. Of the Closing head emerges during the outward opening stroke movement of the valve member from the bore and a formed on the closing head control edge is at least one Injection opening free. It can be provided that several Injection openings are provided which through the control edge be turned on one after the other. This results in the Possibility by limiting the opening stroke of the valve member on a partial stroke only a part of the injection openings or only a partial cross section of an injection opening to control and thus the entire effective Injection cross section depending on the opening stroke of the valve member to control. The opening stroke is by a arranged in the valve body control piston to a partial stroke limited, whose end face a hydraulic control room limited. The control room is under high with fuel Pressure fillable and can thereby the control piston in the axial Move the direction from a first to a second position, whereby the valve member either the maximum stroke or only a partial lift. Such a hydraulic adjustable stroke stop has a black and white function, that is, he leaves no gradations between the two Opening strokes too. This limits the ability to control the Fuel injection process, so that further optimization the injection process is difficult.

Even with a fuel injection valve the inward opening Type, as is known from DE 197 29 843 A1, can it may be desirable to accurately meter a pre-injection amount to have a partial lift available not exhausted in a black and white function, so that one optimal injection rate can be achieved.

Advantages of the invention

The fuel injection valve according to the invention for internal combustion engines with the characterizing features of claim 1 has the advantage that between the closing spring and the guided portion of the valve member, a combined hydraulic and piezo-controlled stroke stop is formed, with which the opening stroke of the valve member to any value between the maximum Opening stroke and the partial stroke can be adjusted. By combining the hydraulically adjustable piston with a piezo actuator, it is possible not only to switch the hydraulic piston between the maximum stroke and the partial stroke, but also to energize the piezo actuator between the partial stroke and any value between partial stroke and maximum opening stroke of the valve member. As a result, an optimally adapted opening stroke of the valve member can be realized in a wide characteristic range of the engine. If you only want to switch between partial stroke and maximum opening stroke, the piezo actuator does not have to be energized, which is energetically advantageous.
In addition to the use of the combined hydraulic and piezo-controlled stroke stop in an outwardly opening Vario nozzle, it is also possible to use the subject of the invention in an inwardly opening fuel injection valve in the same advantageous manner.
In an advantageous embodiment of the stroke stop the control piston is designed as a hollow cylinder, is arranged at the combustion chamber remote from the end of the piezo actuator. As a result, a simple mounting option of the control piston is given, since the piezo actuator and the non-piezo-active part of the control piston can be installed separately. In a control piston constructed in this way, in a further advantageous embodiment, the valve member does not come to rest directly on the piezo actuator during the opening stroke movement, but rather with the interposition of an intermediate disk. This results in less wear on the piezo actuator and thus longer life of the hydraulic stroke stop. In addition, the washer offers the ability to adjust the maximum opening stroke on the thickness of this simple and thus inexpensive to produce intermediate disc by replacing.
In a further advantageous embodiment, the control pressure for controlling the hydraulic stroke stop is taken from a control line which is connected to a high-pressure reservoir via a control valve. The control line is also connected via a further control valve with the largely pressureless fuel reservoir tank, so that via a suitable control of the two valves, a load and unload the control line is possible without a further high-pressure fuel source is needed.

Further advantages and advantageous embodiments of the subject The invention are the description, the drawing and the claims.

drawing

Figur 1 einen Längsschnitt durch ein Kraftstoffeinspritzventil,

Figur 2 eine vergrößerte Darstellung des in Figur 1 mit II bezeichneten Ausschnitts im Bereich des Schließkopfs,

Figur 3 eine vergrößerte Darstellung des in Figur 1 mit III bezeichneten Ausschnitts im Bereich des Hubanschlags,

Figur 4 den schematischen Aufbau des Kraftstoffzufuhrsystems für die Kraftstoffeinspritzung und zur Bereitstellung von Kraftstoffsteuerdruck für den hydraulisch verstellbaren Hubanschlag und

Figur 5 ein erfindungsgemäßes Kraftstoffeinspritzventil der nach innen öffnenden Bauart im Längsschnitt.

An embodiment of the fuel injection valve for internal combustion engines according to the invention is shown in the drawing and will be explained in more detail in the following description. It shows the

1 shows a longitudinal section through a fuel injection valve,

FIG. 2 shows an enlarged view of the section designated II in FIG. 1 in the region of the closing head;

FIG. 3 is an enlarged view of the section in FIG. 1 labeled III in the area of the stroke stop;

Figure 4 shows the schematic structure of the fuel supply system for the fuel injection and to provide fuel control pressure for the hydraulically adjustable stroke stop and

5 shows a fuel injection valve according to the invention of the inwardly opening type in longitudinal section.

Description of the embodiment

FIG. 1 shows a fuel injection valve for internal combustion engines the outwardly opening design. In one Valve body 1, which may be constructed in several parts, is a Bore 2 formed in a piston-shaped, opposite the force of a closing spring 21 axially movable valve member 5 is arranged. The valve member 5 is in an in Figure 1 shown above, brennraumabgewandten section of Bore 2 out, while the combustion chamber facing section of the valve member 5, in Figure 1 below, from a pressure chamber 11 is surrounded, which is formed over a valve body 1 in the Inlet channel 3 can be connected to a high-pressure fuel source is. The valve member 5 is the combustion chamber side in one enlarged in diameter closing head 10 over, in a in the larger diameter portion of the bore 2 out is.

In Figure 2 is an enlarged view of the closing head 10 and the surrounding valve body 1. On the outside wall of the closing head 10 are two rows of injection openings 13a and 13b arranged, with a row all Includes injection holes at the same height of the closing head are arranged. The injection openings 13a and 13b are via injection channels 12 formed in the closing head 10 are connected to the pressure chamber 11. When closed the fuel injection valve comes on the closing head 10 trained valve sealing surface 15 at the valve seat as a surface 17 formed end face of the valve body. 1 to the plant and the injection ports 13a, 13b are from Covered valve body 1. By compared to the valve member 5 larger diameter of the closing head 10 is on Brennraumabgewandten end of the closing head 10 a pressure shoulder 18 formed the fuel pressure in the pressure chamber 11 is suspended. As an alternative to that shown in FIG Embodiment, it may also be provided that more than two rows of axially offset from each other injection openings 13a, 13b on the outer surface of the Closing head 10 are arranged. In a further embodiment It may also be provided that on the outer circumferential surface the closing head 10 only a series of injection openings 13a, 13b is provided, whose cross section in the opening stroke of the valve member 5 all or only partially opened.

The valve member 5 is at its end remote from the combustion chamber in a spring plunger 24 via, which is up in a brennraumabgewandten Area of the valve body 1 formed spring chamber 20 sticks out. At the combustion chamber opposite end of the spring plunger 24, a spring plate 23 is formed, at which the Closing spring 21 is supported with its combustion chamber opposite end. The spring chamber 20 is a in the valve body. 1 trained and not shown in the drawing flow channel connected to a drain line to the in the Spring chamber 20 to dissipate penetrating leak oil.

3 shows an enlarged view of the adjustable Stroke stop of figure 1. Between the guided section the valve member 5 and the spring chamber 20 is an im Diameter larger guide bore 6 is formed. In the Guide bore 6 is connected to the valve body 1 Control stop 31 arranged and an axially in the guide bore 6 movable control piston 30. The control stop 31 is at the spring chamber 20 far end of the guide hole 6 arranged and formed as a hollow cylinder whose inner diameter Tiered is formed, the section with the larger inner diameter facing the spring chamber 20 is. The control piston 30 is likewise designed as a hollow cylinder, wherein this formed stepped in the outer diameter is and the outer diameter smaller section of the Feather chamber 20 faces away. The smaller in outer diameter Section of the control piston 30 dips into the inside diameter larger portion of the control stop 31, wherein between the control piston 30 and the control stop 31 a Throttle gap 45 is formed. The on the control piston 30 combustion chamber side formed by the stepped outer diameter outer annular end face 35 on the one hand and the control stop 31 on the other hand limit a control room 33, too a trained in the valve body 1 control channel 34th leads. About the throttle gap 45 can only little fuel from the control chamber 33 on the valve member 5 over into the spring chamber 20 drain. The control piston 30 is in two parts constructed, wherein the spring chamber 20 facing, hollow cylindrical Section is designed as a piezoelectric actuator 26 and the other part a stepped trained hydraulic piston 27 forms. For energizing the piezo-actuator 26 are at this suitable electrical contacts arranged, which have an in the drawing, not shown electrical line with a suitable voltage source are connected. It can the electrical line for example in a separate, be guided in the valve body 1 formed channel, or through the spring chamber 20 and not shown in the drawing Outflow channel of the spring chamber 20 led to the outside be.

The spring chamber 20 is facing the piezoelectric actuator 26, a support disk 25 arranged facing the spring chamber 20 End face is designed as Hubanschlagfläche 42, the at the directed to the spring chamber 20 stroke movement of the Control piston 30 at one by the cross-sectional reduction from the guide bore 6 to the spring chamber 20 formed control piston stop 43 comes to the plant. In the spring chamber 20 is a Federabstützring 22 is arranged, on which the closing spring 21 is supported with its combustion chamber end side. The spring support ring 22 is guided in the spring chamber 20 and is by the force of the closing spring 21 against the support disk 25 pressed. At the transition of the valve member 5 to the spring plunger 24 is formed on the valve member 5, a circumferential annular collar 40, whose facing the combustion chamber annular end face as Stop surface 41 is formed. In the direction of the combustion chamber Opening stroke of the valve member 5 comes this Stop surface 41 formed on the intermediate disc 25 on Hubanschlagfläche 42 to the plant, whereby the opening stroke is limited.

FIG. 4 shows the structure of the high-pressure fuel supply shown schematically. From a fuel storage tank 50 Fuel is via a low pressure line 51 of a high-pressure fuel pump 52 supplied. The high-pressure fuel pump 52 pumps fuel under high pressure High pressure line 53 in a high-pressure accumulator 55. Für each fuel injection valve 101 of the internal combustion engine a fuel supply line 60 goes from the high-pressure storage space 55 from the fuel injection valve 101 to the inlet channel 3 is connected. Here is between inlet channel 3 and fuel supply line 60 a metering valve 67 arranged with the connection from the high-pressure reservoir 55 to Inlet channel 3 can be opened or closed. Of the High-pressure accumulator 55 is connected via a control valve 57 with a control line 58 connectable. Because in the high-pressure storage room 55 always maintained a certain high fuel pressure can, by opening the control valve 57 fuel under high pressure in the control line 58 are passed, whereby the pressure in the control line 58 in the high pressure storage space 55 equalizes. Every fuel injection valve 101 is connected via a control feed line 59, which with the Control channel 34 is connected in the valve body 1, with the Control line 58 connected. The control line 58 is over a drain line 63 in which a control valve 61 is arranged is, with the serving as a discharge space fuel tank 50 connectable. By opening the control valve 61 leaves the pressure in the control line 58 at any time on the Relieve pressure level of the fuel storage tank 50, the approximate corresponds to the atmospheric pressure. The entire Fuel injection system is controlled by a control unit 65, which contains a calculator, the by the measured values various, not shown in the drawing sensors the high-pressure fuel pump 52, the control valves 61 and 57, the metering 67 and the energization of the piezo actuator 26 controls.

Zu Beginn des Einspritzvorgangs öffnet das Zumeßventil 67 die Verbindung von der Kraftstoffzulaufleitung 60 zum Zulaufkanal 3. Dadurch strömt Kraftstoff aus dem Hochdruckspeicherraum 55 durch die Kraftstoffzulaufleitung 60 und den Zulaufkanal 3 in den Druckraum 11. Der Kraftstoffdruck im Druckraum 11 steigt an, bis die resultierende Kraft in axialer Richtung auf die Druckschulter 18 größer ist als die Kraft der Schließfeder 21. Das Ventilglied 5 bewegt sich nach außen auf den Brennraum zu, wodurch die beiden Einspritzöffnungen 13a und 13b nacheinander aus der Bohrung 2 austauchen, wodurch der Druckraum 11 mit dem Brennraum verbunden wird und Kraftstoff in den Brennraum eingespritzt wird. Durch die nach außen gerichtete Öffnungshubbewegung des Ventilgliedes 5 bewegt sich auch der Ringbund 40 in Richtung Brennraum und damit die Anschlagfläche 41 auf die Hubanschlagfläche 42 zu. Ob das Ventilglied 5 den maximalen Hub h durchfährt oder nur einen Teilhub, hängt vom Zustand des Steuerkolbens 30 ab.

The operation of the fuel injection valve shown in Figure 1 is as follows:

At the beginning of the injection process, the metering valve 67 opens the connection from the fuel supply line 60 to the inlet channel 3. As a result, fuel flows from the high-pressure reservoir 55 through the fuel supply line 60 and the inlet channel 3 into the pressure chamber 11. The fuel pressure in the pressure chamber 11 increases until the resulting force in the axial direction of the pressure shoulder 18 is greater than the force of the closing spring 21. The valve member 5 moves outwardly toward the combustion chamber, whereby the two injection ports 13a and 13b successively dive out of the bore 2, whereby the pressure chamber 11 connected to the combustion chamber and fuel is injected into the combustion chamber. The outward opening stroke of the valve member 5, the annular collar 40 moves in the direction of the combustion chamber and thus the stop surface 41 on the Hubanschlagfläche 42. Whether the valve member 5 passes through the maximum stroke h or only a partial stroke depends on the state of the control piston 30.

Im geschlossenen Zustand des Kraftstoffeinspritzventils, das heißt, wenn die Ventildichtfläche 15 an der Ventilsitzfläche 17 anliegt und wenn der Steuerraum 33 des hydraulischen Hubanschlags drucklos und der Piezo-Aktor 26 nicht bestromt ist, hat die Hubanschlagfläche 42 von der Anschlagfläche 41 des Ringbunds 40 einen axialen Abstand, der dem maximalen Öffnungshub h des Ventilgliedes 5 entspricht. Dieser Zustand ist in der Figur 3 in der linken Hälfte dargestellt. Ist der Steuerraum 33 ohne Kraftstoffdruck, so liegt die innere Ringstirnfläche 36 des Steuerkolbens 30 an der Sitzfläche 37 des Steueranschlags 31 an. Wird nun bei geöffnetem Steuerventil 57 und geschlossenem Steuerventil 61 Kraftstoff über den Steuerkanal 34 in den Steuerraum 33 eingeführt, so erhöht sich der Kraftstoffdruck im Steuerraum 33, bis die resultierende Kraft auf die äußere Ringstirnfläche 35 größer als die Kraft der Schließfeder 21 ist. Der Steuerkolben 30 bewegt sich auf den Federraum 20 zu, bis er nach Durchfahren des Steuerhubs s mit der Hubanschlagfläche 42 an dem Steuerkolbenanschlag 43 zur Anlage kommt. Dieser Zustand ist in der Figur 3 in der rechten Hälfte dargestellt. Der Steuerhub s ist dabei kleiner als der maximale Öffnungshub h. Bei der Öffnungshubbewegung des Ventilgliedes 5 kommt die Anschlagfläche 41 nach durchfahren des Hubes h-s an der Hubanschlagfläche 42 zur Anlage. Der Steuerhub s beträgt etwa 30 bis 70 % des maximalen Öffnungshubes h, so daß durch Druckbeaufschlagung des Steuerraums 33 und die dadurch bewirkte Hubbewegung des Steuerkolbens 30 die Öffnungshubbewegung des Ventilgliedes 5 auf 70 bis 30 % des maximalen Öffnungshubes h beschränkt wird. Soll das Ventilglied 5 wieder den maximalen Öffnungshub h durchfahren, wird der Druck im Steuerraum 33 reduziert, indem die Steuerleitung 58 bei geschlossenem Steuerventil 57 über das Steuerventil 61 und die Ablaufleitung 63 in den Kraftstoffvorratstank 50 entlastet wird. Übersteigt die Kraft der Schließfeder 21 die Kraft des Kraftstoffdrucks auf die innere Ringstirnfläche 36 des Steuerraums 33, so wird der Steuerkolben 30 von der Schließfeder 21 zum Brennraum hin gepreßt, bis die innere Ringstirnfläche 36 an der Sitzfläche 37 anliegt. Soll die Hubanschlagfläche 42 nur einen Teil des Steuerhubs s durchfahren, wird der Piezo-Aktor 26 bestromt. Durch die Längenänderung des Piezo-Aktors 26 aufgrund der angelegten Spannung kann die Hubanschlagfläche 42 stufenlos auf jeden beliebigen Teil des Steuerhubs s angehoben werden. Die maximal mögliche Längenänderung des Piezo-Aktors 26 entspricht dabei beispielsweise in etwa dem Steuerhub s.

The operation of the adjustable stroke stop is as follows:

In the closed state of the fuel injection valve, that is, when the valve sealing surface 15 rests against the valve seat surface 17 and when the control chamber 33 of the hydraulic Hubanschlags depressurized and the piezoelectric actuator 26 is energized, the Hubanschlagfläche 42 of the stop surface 41 of the annular collar 40 has an axial Distance corresponding to the maximum opening stroke h of the valve member 5. This state is shown in Figure 3 in the left half. If the control chamber 33 without fuel pressure, then the inner annular end face 36 of the control piston 30 abuts against the seat surface 37 of the control stopper 31. If fuel is now introduced into the control chamber 33 via the control channel 34 when the control valve 57 is open and the control valve 61 is closed, the fuel pressure in the control chamber 33 increases until the resulting force on the outer annular end face 35 is greater than the force of the closing spring 21. The control piston 30 moves toward the spring chamber 20 until it comes to rest on the control piston stop 43 after passing through the control stroke s with the stroke stop surface 42. This state is shown in the right half in FIG. The control stroke s is smaller than the maximum opening stroke h. In the opening stroke of the valve member 5, the stop surface 41 comes to drive through the stroke hs at the Hubanschlagfläche 42 to the plant. The Steuerhub s is about 30 to 70% of the maximum opening stroke h, so that the opening stroke of the valve member 5 is limited to 70 to 30% of the maximum opening stroke h by pressurizing the control chamber 33 and thereby caused lifting movement of the control piston. If the valve member 5 again passes through the maximum opening stroke h, the pressure in the control chamber 33 is reduced by the control line 58 is relieved with the control valve 57 closed via the control valve 61 and the drain line 63 into the fuel storage tank 50. If the force of the closing spring 21 exceeds the force of the fuel pressure on the inner annular end face 36 of the control chamber 33, the control piston 30 is pressed by the closing spring 21 toward the combustion chamber until the inner annular end face 36 bears against the seat surface 37. If the stroke stop surface 42 only passes through part of the control stroke s, the piezo actuator 26 is energized. Due to the change in length of the piezo-actuator 26 due to the applied voltage, the Hubanschlagfläche 42 can be continuously increased to any part of the Steuerhubs s. The maximum possible change in length of the piezoelectric actuator 26 corresponds, for example, approximately to the control stroke s.

FIG. 5 shows a longitudinal section of a fuel injection valve of the inwardly opening type according to the invention. In a valve body 80 designed as a blind bore bore 90 is arranged, the bottom surface facing the combustion chamber. On the bottom surface, a conical valve seat 83 is formed and at least one injection port 92, which connects the bore 90 with the combustion chamber. The valve body 80 is braced by means of a clamping nut 98 with the interposition of an intermediate disc 94 against a valve holding body 96, which may be constructed in several parts.
In the bore 90 a piston-shaped, against the force of a closing spring 21 longitudinally displaceable valve member 100 is arranged, which is sealingly guided in a brennraumabgewandten portion of the bore 90 and merges toward the combustion chamber to form a pressure shoulder 88 in a smaller diameter section. At the combustion chamber end, a valve sealing surface 81 is formed on the valve member 100, which cooperates with the valve seat 83 and thus opens the injection openings 92 by the longitudinal movement of the valve member 100 and closes. The pressure shoulder 88 is arranged in a pressure chamber 11 formed in the valve body 80, which continues to the valve seat 83 into an annular gap surrounding the valve member 100 and can be filled with fuel via an inlet channel 3 formed in the valve body 80. By the hydraulic force on the pressure shoulder 88, the valve member 100 can be moved against the force of the closing spring 21 in the bore 90, so that the injection ports 92 are turned on.
At the end facing away from the combustion chamber, the valve member 90 passes into a spring plate 103 and subsequently into a spring tappet 107, both of which are arranged in a spring space 105 formed in the valve holding body 96. The spring chamber 105 is formed stepped in diameter and increases toward the end facing away from the combustion chamber to form a control piston stop surface 43 designed as an annular shoulder.

At Brennraumabgewandten end of the spring chamber 105 is a combined, Hydraulic and piezo controlled stroke stop arranged as he described earlier in the description the outward-opening fuel injection valve of FIG 1 and Figure 3 is described, so that at this point only a few details will be discussed. The control piston 30 is arranged facing the combustion chamber to the control stop 31, and between its end facing the combustion chamber and the Spring plate 103 is the spring plunger 107 surrounding Closing spring 21 is arranged, which the valve member 100 with the Valve sealing surface 81 against the valve seat 83 presses. The valve member 100 has a combustion chamber facing away from its end Stop surface 109, which by the opening stroke the valve member 100 away from the combustion chamber on the control piston 30th comes to the plant. When activating the hydraulic stop or the piezo actuator moves the control piston 30 against the force of the closing spring 21, wherein the control piston stop surface 43 the maximum travel of the spool 30 limited. This also shifts the on the control piston 30 trained Hubanschlagfläche 42 and reduces so the maximum possible opening stroke of the valve member 100th

As an alternative to the hydraulic shown in FIG. 3 or FIG Hubanschlag it can also be provided that the entire control piston 30 is designed as a piezo actuator. This eliminates the compound of preferably made of metal manufactured hydraulic piston 27 and the piezo-actuator 26th Further, it may also be provided that the support plate 25th omitted and the Hubanschlagfläche 42 formed on the piezoelectric actuator 26 is.

It should be noted in FIGS. 1, 3 and 5 that the piezoactuator 26 for the sake of clarity only shown schematically has been. The size, in particular the axial extent of the Piezo-actuator 26, must according to the particular application be chosen taking into account the low relative Length change of the piezo actuator.

Claims (15)

1. Fuel injection valve for internal combustion engines, with a valve body (1, 80), in which is arranged in a bore (2, 90) a piston-shaped valve member (5, 100) which is axially movable counter to the closing force and which, on a portion of its length facing away from the combustion space, is guided in the bore (2) and, on a portion arranged from the guided portion towards the combustion space, is surrounded by a pressure space (11) which is formed in the valve body (1, 80) and is connectable to a high-pressure fuel source (55) and in which is arranged a pressure shoulder (18) of the valve member (5, 100), the said pressure shoulder acting in the opening direction, which valve member (5, 100) controls, by means of its end region facing the combustion space, at least one injection orifice (13a, 13b, 92) which, as a result of an opening-stroke movement of the valve member (5, 100) counter to the closing force, can be opened completely or partially and can consequently be connected to the pressure space (11), and with an axially movable control piston (30) which limits the maximum opening stroke of the valve member (5, 100) and one end face of which serves as a stroke stop face (42) for limiting the opening-stroke movement of the valve member (5, 100) and the other annual end face (35) of which delimits a control space (33) connectable to a high-pressure fuel source, characterized in that the control piston (30) is designed at least partially as a piezoelectric actuator (26).
2. Fuel injection valve according to Claim 1, characterized in that the valve member (5, 100) has formed on it a stop face (41, 109) which comes to bear on this stroke stop face (42) during the opening-stroke movement.
3. Fuel injection valve according to Claim 2, characterized in that the control piston (30) is designed as a hollow cylinder which is arranged coaxially with respect to the valve member (5, 100) and which is guided in a guide bore (6).
4. Fuel injection valve according to Claim 3, characterized in that the control piston (30) is designed as a stepped piston, of which the end face facing the stop face (41, 109) is designed as a stroke stop face (42) and of which the annular end face (35) formed by means of the cross-sectional transition and facing away from the stroke stop face (42) delimits the control space (33).
5. Fuel injection valve according to Claim 4, characterized in that the piezoelectric actuator (26) has a hollow-cylindrical design and is arranged coaxially with respect to the valve member (5, 100).
6. Fuel injection valve according to Claim 5, characterized in that the control piston (30) is designed partially as a piezoelectric actuator (26), and the piezeoelectric actuator (26) is arranged so as to face the stop face (41, 109) of the valve member (5, 100).
7. Fuel injection valve according to Claim 5, characterized in that, on that end face of the control piston (30) which faces the stop face (41, 109) of the valve member (5, 100), a supporting disc (25) is arranged, on which the stroke stop face (42) is formed.
8. Fuel injection valve according to Claim 1, characterized in that the closing force is applied by at least one closing spring (21) arranged in a spring space (20, 105).
9. Fuel injection valve according to Claim 8, characterized in that, at the transition of the guide bore (6) to the spring space (20, 105), a control-piston stop face (43) designed as an annular end face is arranged, which limits the axial movement of the control piston (30) in the direction of the stop face (41, 109) formed on the valve member (5, 100).
10. Fuel injection valve according to one of the preceding claims, characterized in that, in order to open the injection orifices (13a, 13b), the valve member (5) executes an opening-stroke movement directed outwards towards the combustion space.
11. Fuel injection valve according to Claim 10, characterized in that the valve member (5) has formed on it an annular collar (40), of which the annual end face facing the combustion space is designed as a stop face (41) which cooperates with the stroke stop face (42) of the control piston (30).
12. Fuel injection valve according to Claim 11, characterized in that the closing spring (21) bears at least indirectly against that end face of the control piston (30) which faces away from the combustion space, so that the closing spring (21) counteracts the stroke of the control piston (30).
13. Fuel injection valve according to one of the preceding claims, characterized in that the control space (33) can be connected to the high-pressure fuel source (55) via a control valve (57).
14. Fuel injection valve according to Claim 13, characterized in that the control space (33) can be connected to a relief space (50) via a control valve (61).
15. Fuel injection valve according to Claim 13, characterized in that the high-pressure fuel source is designed as a high-pressure accumulator space (55).

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