EP1476655B1 - Fuel injection system for an internal combustion engine - Google Patents

Fuel injection system for an internal combustion engine Download PDF

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Publication number
EP1476655B1
EP1476655B1 EP02792635A EP02792635A EP1476655B1 EP 1476655 B1 EP1476655 B1 EP 1476655B1 EP 02792635 A EP02792635 A EP 02792635A EP 02792635 A EP02792635 A EP 02792635A EP 1476655 B1 EP1476655 B1 EP 1476655B1
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EP
European Patent Office
Prior art keywords
control
pressure
space
fuel
fuel injection
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Expired - Lifetime
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EP02792635A
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German (de)
French (fr)
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EP1476655A1 (en
Inventor
Peter Boehland
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Robert Bosch GmbH
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Robert Bosch GmbH
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M47/00—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure
    • F02M47/02—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure of accumulator-injector type, i.e. having fuel pressure of accumulator tending to open, and fuel pressure in other chamber tending to close, injection valves and having means for periodically releasing that closing pressure
    • F02M47/027—Electrically actuated valves draining the chamber to release the closing pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M45/00—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
    • F02M45/02—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts
    • F02M45/04—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts with a small initial part, e.g. initial part for partial load and initial and main part for full load
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M45/00—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
    • F02M45/02—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts
    • F02M45/04—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts with a small initial part, e.g. initial part for partial load and initial and main part for full load
    • F02M45/08—Injectors peculiar thereto
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M57/00—Fuel-injectors combined or associated with other devices
    • F02M57/02—Injectors structurally combined with fuel-injection pumps

Definitions

  • the invention is based on a Fuel injection device for an internal combustion engine according to the preamble of claim 1.
  • Such a fuel injection device is characterized by the EP 0 987 431 A2.
  • These Fuel injection device has a High-pressure fuel pump and a connected to this Fuel injector for each cylinder of Internal combustion engine.
  • the high-pressure fuel pump points one by the internal combustion engine in a reciprocating motion powered pump piston having a pump working space limited.
  • the fuel injection valve has one with the Pump work space associated pressure room and one Injection valve member, through which at least one Injection opening is controlled and by the in the Pressure chamber prevailing pressure against a closing force in Opening direction for releasing the at least one Injection opening is movable. It is a first electric actuated control valve provided by the one Connection of pump work space with a discharge chamber is controlled.
  • control pressure chamber is replaced by a Control piston limited, the control piston of the im Control pressure chamber prevailing pressure applied in one Closing direction acts on the injection valve member and is movable together with the injection valve member.
  • the Control pressure chamber has a connection with the Pump workroom on.
  • To a fuel injection is the first control valve closed and the second Control valve open, so that in the control pressure chamber no High pressure can build up and the fuel injector can open.
  • With opened second control valve flows however, from the pump working space via the control pressure chamber Fuel off, so that available for injection standing amount of fuel through the pump piston subsidized fuel quantity is reduced and also the reduced pressure available for injection becomes. It follows that the efficiency of Fuel injector is not optimal.
  • the fuel injection device according to the invention with the Features according to claim 1 has the advantage that acted upon by the pressure prevailing in the control pressure chamber pressure End face of the control piston can be kept low, whereby required for the function réelle beflußquerroughen the throttle bodies at opened second control valve outflowing amount of fuel can be kept low and thus the efficiency of Fuel injection device is improved.
  • FIG. 1 shows a Fuel injection device for an internal combustion engine in a schematic representation
  • Figure 2 a in Figure 1 with II designated section of the Fuel injection device according to a modified Execution in an enlarged view
  • Figure 3 the Section II of the fuel injection device according to a another modified embodiment
  • Figure 4 shows a course a pressure at injection ports of a Fuel injection valve of the Fuel injector.
  • FIG. 1 to 3 is a Fuel injection device for an internal combustion engine a motor vehicle shown.
  • the internal combustion engine is preferably a self-igniting internal combustion engine.
  • the Fuel injection device is preferably as So-called pump-nozzle unit is designed and has for each cylinder of the internal combustion engine one each High-pressure fuel pump 10 and connected to this Fuel injection valve 12, which has a common Form building unit.
  • the Fuel injection device as a so-called pump-line-nozzle system be trained in which the High-pressure fuel pump and the fuel injection valve each cylinder is arranged separately from each other and over a line are connected together.
  • the High-pressure fuel pump 10 has a pump body 14 with a cylinder bore 16 in which a pump piston 18th is tightly guided, at least indirectly by a Cam 20 of a camshaft of the internal combustion engine opposite the force of a return spring 19 in a lifting movement is driven.
  • the pump piston 18 limited in the Cylinder bore 16 a pump working chamber 22, in the at Delivery stroke of the pump piston 18 Fuel under high pressure is compressed.
  • the pump working chamber 22 becomes fuel from a fuel tank 24 of the motor vehicle fed.
  • the fuel injection valve 12 has one with the Pump body 14 connected valve body 26, the may be formed in several parts, and in the one Injection valve member 28 in a bore 30th is guided longitudinally displaceable.
  • the valve body 26 indicates its the combustion chamber of the cylinder of the internal combustion engine facing end region at least one, preferably a plurality Injection openings 32.
  • the injection valve member 28 has at its the combustion chamber end facing a For example, about conical sealing surface 34, which with one in the valve body 26 in the combustion chamber facing End region formed valve seat 36 cooperates, from or after which the injection openings 32 dissipate.
  • valve body 26 is between the injection valve member 28 and the bore 30 to the valve seat 36 toward an annular space 38th present, in its the valve seat 36 facing away End region by a radial extension of the bore 30 in a pressure chamber 40 surrounding the injection valve member 28 passes.
  • the injection valve member 28 has the height of the Pressure chamber 40 by a cross-sectional reduction a Pressure shoulder 42 on.
  • a biased Closing spring 44 At the end of the combustion chamber facing away from the Injector member 28 engages a biased Closing spring 44, through which the injection valve member 28th is pressed toward the valve seat 36.
  • the closing spring 44 is arranged in a spring chamber 46 of the valve body 26, the adjoins the bore 30.
  • the bore 48 is stepped in diameter and has a to Spring chamber 46 arranged portion 148 with a large Diameter on and facing away from the spring chamber 46 arranged portion 248 with a small diameter.
  • the Control piston 50 is correspondingly in diameter as well stepped formed and has a in the bore portion 148th tightly guided area 150 with large diameter on and a tightly guided in the bore portion 248 area 250th with a small diameter.
  • In the bore section 248 becomes through the end face of the area 250 of the control piston 50 limited as a movable wall, a control pressure chamber 52.
  • an annular pressure surface 53rd formed with the area 150 of the control piston 50 in Bore portion 148 defines a further pressure chamber 54.
  • the control piston 50 is one opposite this in the Diameter smaller piston rod 51 with the Injection valve member 28 connected.
  • the control piston 50 can formed integrally with the injection valve member 28 is but preferably for reasons of assembly as a separate Part connected to the injection valve member 28.
  • a channel 60 to the pressure chamber 40 of the Fuel injection valve 12.
  • a channel 62 leads to the control pressure chamber 52.
  • the control pressure chamber 52 also opens a channel 64, the makes a connection to a relief room when the at least indirectly, the fuel tank 24 or another area may serve in which a low pressure prevails.
  • From the pump chamber 22 or channel 60 leads a connection 66 to a discharge space 24 from, through a first electrically operated control valve 68 controlled becomes.
  • the control valve 68 may be as shown in FIG be designed as a 2/2-way valve.
  • the connection 64 of Control pressure chamber 52 with the discharge chamber 24 is through controlling a second electrically operated control valve 70, which can be designed as a 2/2-way valve.
  • a throttle point 63 is provided in the Connection 62 of the control pressure chamber 52 with the Pump work chamber 22 and in the connection of the control pressure chamber 52 with the Relief space 24, a throttle point 65 is provided.
  • the throttle bodies 63,65 By suitable dimensioning of the throttle bodies 63,65 the inflow of fuel from the pump working space 22 in the control pressure chamber 52 and the outflow of fuel the control pressure chamber 52 to a required extent be set.
  • a sufficient inflow of fuel in the control pressure chamber 52 is for a quick closing required and the fuel injection valve 12 sufficient drainage of fuel from the control pressure chamber 52 is for a quick opening of the Fuel injection valve 12 required.
  • the Control valves 68,70 may be an electromagnetic actuator or have a piezoelectric actuator and are by a electronic control device 72 is controlled.
  • the further pressure chamber 54 has a connection 56, for example, in the form of a channel, with the Pumping room 22, for example, in the channel 60 can lead.
  • connection 56 is not a throttle point available.
  • the additional pressure chamber 54 is thus bypassed the throttle point 63 of the connection 62 of the control pressure chamber 52 with the pump work chamber 22 directly to the Pumping room 22 connected and on the pressure surface 53rd the control piston 50 acts the same pressure as in Pump work chamber 22 and in the pressure chamber 40th
  • a closing spring 44 supporting force in the closing direction on the Injection valve member 28 generated.
  • FIG 2 is a detail of a modified embodiment the fuel injection device shown in which the basic structure is the same as described above, However, the pressure surface 53 at one of the control piston 50th separate piston 55 is formed.
  • the control piston 50 in this case has only the tightly guided in the bore section 248 Control piston area 250, with its end face the Control pressure chamber 52 limited.
  • the control piston 50 is over the piston rod 51 with the injection valve member 28th connected.
  • the piston 55 replaces the spool area 150 the embodiment of Figure 1 and is also about a Piston rod 57 connected to the injection valve member 28, wherein the piston rod 51 of the control piston 50 through the Piston 55 and the piston rod 57 passes.
  • FIG 3 is fragmentary a modified embodiment the fuel injection device shown in which the basic structure again the same as in the execution according to Figure 1, but the design of the control piston and the connection of the control pressure chamber 52 to the Pump working space 22 is modified.
  • the control piston 50 in turn has the in the bore section 148 with larger diameter tightly guided area 150 and the im Bore portion 248 of smaller diameter tight guided area 250 on.
  • the control pressure chamber 52nd limited and by the annular pressure surface 53 of the Control piston area 150, the further pressure chamber 54th limited.
  • the further pressure chamber 54 is over the connection 56 with the channel 60 and over this with the Pump workspace 22 connected.
  • connection 162 In the control piston area 250 is a connection 162, for example in the form of a Hole formed through which the control pressure chamber 52 with the further pressure chamber 54 is connected.
  • connection 162 In the connection 162 is a throttle point 163 provided by the Compound 162 itself may be formed when using this is designed according to a small cross-section.
  • the Bore portion 148 the same diameter as the Spring chamber 46.
  • an intermediate disc 58th provided at which the closing spring 44 in the spring chamber 46th supported.
  • Between the piston rod 51 and the Injection valve member 28 may be a shim 59th be arranged with the distance between the Control piston 50 and the injection valve member 28 is set can be.
  • FIG. 4 is the Course of the pressure p at the injection openings 32 of the Fuel injection valve 12 over the time t during a Injection cycle shown.
  • the suction stroke of the pump piston 18 gets this fuel from the fuel tank 24 supplied.
  • the delivery stroke of the pump piston 18 begins the fuel injection with a pilot injection, wherein the first control valve 68 by the controller 72nd is closed, so that the pump chamber 22 from Relief space 24 is disconnected.
  • the second control valve 70 is also opened so that the control pressure chamber 52 connected to the discharge chamber 24 is. In this case, in the control pressure chamber 52 no Build high pressure, as this to the relief space 24 out is relieved.
  • Control valve 70 is closed, so that the control pressure chamber 52nd is separated from the discharge space 24.
  • the first control valve 68 remains in its closed position. in the Control pressure chamber 52 builds up high pressure as in Pumping work chamber 22, so that on the control piston 50th a large pressure force acts in the closing direction. Furthermore increases with closed second control valve 70 of Pressure in the pump working chamber 22 and thus also in the other Pressure chamber 54, so that over the pressure surface 53 a increased force in the closing direction on the Injection valve member 28 is generated. Since now on the Injection valve member 28 acting in the opening direction 29 Force is less than the sum of the force of the closing spring 44, the pressure force on the control piston 50 and the Pressure force on the pressure surface 53 closes the Fuel injection valve 12.
  • the pilot injection corresponds a designated in Figure 4 with I injection phase.
  • the one in FIG 4 corresponds to II designated injection phase
  • the second control valve 70 by the controller 72nd opened, so that the pressure in the control pressure chamber 52 decreases.
  • the Fuel injection valve 12 then opens as a result of reduced pressure force on the control piston 50 and the Injector member 28 moves above its maximum Opening stroke.
  • the Pressure surface 53 at the transition between the Bore sections 148 and 248 formed annular shoulder for Plant come.
  • the injection valve member 28 may also another stroke stop to limit this Opening movement to be provided.
  • the first Control valve 68 by the controller 72 in his opened switch position, so that the Pump working space 22 connected to the discharge chamber 24 is and on the injection valve member 28 in the opening direction 29 only a small pressure force acts and that Fuel injection valve 12 due to the force of Closing spring 44, by the control pressure in the space 52nd prevailing residual pressure on the control piston 50 generated Force and by the in the further pressure chamber 54 on the Pressure surface 53 generated force closes.
  • the second Control valve 70 may terminate the Main injection in its open or closed Position.
  • Fuel injection device can be additionally provided be that the flow area from the control pressure chamber 52 to the discharge chamber 24 by the control piston 50 dependent is variably controlled by its stroke.
  • the Control piston 50 is doing in a stroke position accordingly the closed position of the injection valve member 28 a large flow area released and in one Lift position corresponding to the open position of the Injection valve member 28 a small flow area Approved.

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einer Kraftstoffeinspritzeinrichtung für eine Brennkraftmaschine nach der Gattung des Anspruchs 1.The invention is based on a Fuel injection device for an internal combustion engine according to the preamble of claim 1.

Eine solche Kraftstoffeinspritzeinrichtung ist durch die EP 0 987 431 A2 bekannt. Diese Kraftstoffeinspritzeinrichtung weist eine Kraftstoffhochdruckpumpe und ein mit dieser verbundenes Kraftstoffeinspritzventil für jeden Zylinder der Brennkraftmaschine auf. Die Kraftstoffhochdruckpumpe weist einen durch die Brennkraftmaschine in einer Hubbewegung angetriebenen Pumpenkolben auf, der einen Pumpenarbeitsraum begrenzt. Das Kraftstoffeinspritzventil weist einen mit dem Pumpenarbeitsraum verbundenen Druckraum und ein Einspritzventilglied auf, durch das wenigstens eine Einspritzöffnung gesteuert wird und das durch den im Druckraum herrschenden Druck gegen eine Schließkraft in Öffnungsrichtung zur Freigabe der wenigstens einen Einspritzöffnung bewegbar ist. Es ist ein erstes elektrisch betätigtes Steuerventil vorgesehen, durch das eine Verbindung des Pumpenarbeitsraums mit einem Entlastungsraum gesteuert wird. Es ist außerdem ein zweites elektrisch betätigtes Steuerventil vorgesehen, durch das eine Verbindung eines Steuerdruckraums mit einem Entlastungsraum gesteuert wird. Der Steuerdruckraum wird durch einen Steuerkolben begrenzt, wobei der Steuerkolben vom im Steuerdruckraum herrschenden Druck beaufschlagt in einer Schließrichtung auf das Einspritzventilglied wirkt und zusammen mit dem Einspritzventilglied bewegbar ist. Der Steuerdruckraum weist eine Verbindung mit dem Pumpenarbeitsraum auf. Zu einer Kraftstoffeinspritzung wird das erste Steuerventil geschlossen und das zweite Steuerventil geöffnet, so daß sich im Steuerdruckraum kein Hochdruck aufbauen kann und das Kraftstoffeinspritzventil öffnen kann. Bei geöffnetem zweitem Steuerventil fließt jedoch aus dem Pumpenarbeitsraum über den Steuerdruckraum Kraftstoff ab, so daß die für die Einspritzung zur Verfügung stehende Kraftstoffmenge der durch den Pumpenkolben geförderten Kraftstoffmenge verringert wird und außerdem der für die Einspritzung zur Verfügung stehende Druck verringert wird. Hieraus folgt, daß der Wirkungsgrad der Kraftstoffeinspritzeinrichtung nicht optimal ist.Such a fuel injection device is characterized by the EP 0 987 431 A2. These Fuel injection device has a High-pressure fuel pump and a connected to this Fuel injector for each cylinder of Internal combustion engine. The high-pressure fuel pump points one by the internal combustion engine in a reciprocating motion powered pump piston having a pump working space limited. The fuel injection valve has one with the Pump work space associated pressure room and one Injection valve member, through which at least one Injection opening is controlled and by the in the Pressure chamber prevailing pressure against a closing force in Opening direction for releasing the at least one Injection opening is movable. It is a first electric actuated control valve provided by the one Connection of pump work space with a discharge chamber is controlled. It is also a second electric actuated control valve provided by the one Connection of a control pressure chamber with a discharge space is controlled. The control pressure chamber is replaced by a Control piston limited, the control piston of the im Control pressure chamber prevailing pressure applied in one Closing direction acts on the injection valve member and is movable together with the injection valve member. Of the Control pressure chamber has a connection with the Pump workroom on. To a fuel injection is the first control valve closed and the second Control valve open, so that in the control pressure chamber no High pressure can build up and the fuel injector can open. With opened second control valve flows however, from the pump working space via the control pressure chamber Fuel off, so that available for injection standing amount of fuel through the pump piston subsidized fuel quantity is reduced and also the reduced pressure available for injection becomes. It follows that the efficiency of Fuel injector is not optimal.

Vorteile der ErfindungAdvantages of the invention

Die erfindungsgemäße Kraftstoffeinspritzeinrichtung mit den Merkmalen gemäß Anspruch 1 hat demgegenüber den Vorteil, daß die vom im Steuerdruckraum herrschenden Druck beaufschlagte Stirnfläche des Steuerkolbens gering gehalten werden kann, wodurch bei für die Funktion erforderlichen Mindestdurchflußquerschnitten der Drosselstellen die bei geöffnetem zweitem Steuerventil abfließende Kraftstoffmenge gering gehalten werden kann und damit der Wirkungsgrad der Kraftstoffeinspritzeinrichtung verbessert ist.The fuel injection device according to the invention with the Features according to claim 1 has the advantage that acted upon by the pressure prevailing in the control pressure chamber pressure End face of the control piston can be kept low, whereby required for the function Mindestdurchflußquerschnitten the throttle bodies at opened second control valve outflowing amount of fuel can be kept low and thus the efficiency of Fuel injection device is improved.

In den abhängigen Ansprüchen sind vorteilhafte Ausgestaltungen und Weiterbildungen der erfindungsgemäßen Kraftstoffeinspritzeinrichtung angegeben. Die Ausbildung gemäß Anspruch 3 ermöglicht auf einfache Weise die Anordnung der weiteren Druckfläche. Die Ausbildung gemäß Anspruch 4 und 5 ermöglicht einen einfachen Aufbau der Kraftstoffeinspritzeinrichtung.In the dependent claims are advantageous Embodiments and developments of the invention Fuel injector specified. Training according to claim 3 allows in a simple way the arrangement the further printing surface. The embodiment according to claim 4 and 5 allows a simple construction of the Fuel injector.

Zeichnungdrawing

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Es zeigen Figur 1 eine Kraftstoffeinspritzeinrichtung für eine Brennkraftmaschine in schematischer Darstellung, Figur 2 einen in Figur 1 mit II bezeichneten Ausschnitt der Kraftstoffeinspritzeinrichtung gemäß einer modifizierten Ausführung in vergrößerter Darstellung, Figur 3 den Ausschnitt II der Kraftstoffeinspritzeinrichtung gemäß einer weiteren modifizierten Ausführung und Figur 4 einen Verlauf eines Druckes an Einspritzöffnungen eines Kraftstoffeinspritzventils der Kraftstoffeinspritzeinrichtung.An embodiment of the invention is in the drawing shown and in the following description in more detail explained. FIG. 1 shows a Fuel injection device for an internal combustion engine in a schematic representation, Figure 2 a in Figure 1 with II designated section of the Fuel injection device according to a modified Execution in an enlarged view, Figure 3 the Section II of the fuel injection device according to a another modified embodiment and Figure 4 shows a course a pressure at injection ports of a Fuel injection valve of the Fuel injector.

Beschreibung des AusführungsbeispielsDescription of the embodiment

In den Figuren 1 bis 3 ist eine Kraftstoffeinspritzeinrichtung für eine Brennkraftmaschine eines Kraftfahrzeugs dargestellt. Die Brennkraftmaschine ist vorzugsweise eine selbstzündende Brennkraftmaschine. Die Kraftstoffeinspritzeinrichtung ist vorzugsweise als sogenannte Pumpe-Düse-Einheit ausgebildet und weist für jeden Zylinder der Brennkraftmaschine jeweils eine Kraftstoffhochdruckpumpe 10 und ein mit dieser verbundenes Kraftstoffeinspritzventil 12 auf, die eine gemeinsame Baueinheit bilden. Alternativ kann die Kraftstoffeinspritzeinrichtung auch als sogenanntes Pumpe-Leitung-Düse-System ausgebildet sein, bei dem die Kraftstoffhochdruckpumpe und das Kraftstoffeinspritzventil jedes Zylinders getrennt voneinander angeordnet und über eine Leitung miteinander verbunden sind. Die Kraftstoffhochdruckpumpe 10 weist einen Pumpenkörper 14 mit einer Zylinderbohrung 16 auf, in der ein Pumpenkolben 18 dicht geführt ist, der zumindest mittelbar durch einen Nocken 20 einer Nockenwelle der Brennkraftmaschine entgegen der Kraft einer Rückstellfeder 19 in einer Hubbewegung angetrieben wird. Der Pumpenkolben 18 begrenzt in der Zylinderbohrung 16 einen Pumpenarbeitsraum 22, in dem beim Förderhub des Pumpenkolbens 18 Kraftstoff unter Hochdruck verdichtet wird. Dem Pumpenarbeitsraum 22 wird Kraftstoff aus einem Kraftstoffvorratsbehälter 24 des Kraftfahrzeugs zugeführt.In Figures 1 to 3 is a Fuel injection device for an internal combustion engine a motor vehicle shown. The internal combustion engine is preferably a self-igniting internal combustion engine. The Fuel injection device is preferably as So-called pump-nozzle unit is designed and has for each cylinder of the internal combustion engine one each High-pressure fuel pump 10 and connected to this Fuel injection valve 12, which has a common Form building unit. Alternatively, the Fuel injection device as a so-called pump-line-nozzle system be trained in which the High-pressure fuel pump and the fuel injection valve each cylinder is arranged separately from each other and over a line are connected together. The High-pressure fuel pump 10 has a pump body 14 with a cylinder bore 16 in which a pump piston 18th is tightly guided, at least indirectly by a Cam 20 of a camshaft of the internal combustion engine opposite the force of a return spring 19 in a lifting movement is driven. The pump piston 18 limited in the Cylinder bore 16 a pump working chamber 22, in the at Delivery stroke of the pump piston 18 Fuel under high pressure is compressed. The pump working chamber 22 becomes fuel from a fuel tank 24 of the motor vehicle fed.

Das Kraftstoffeinspritzventil 12 weist einen mit dem Pumpenkörper 14 verbundenen Ventilkörper 26 auf, der mehrteilig ausgebildet sein kann, und in dem ein Einspritzventilglied 28 in einer Bohrung 30 längsverschiebbar geführt ist. Der Ventilkörper 26 weist an seinem dem Brennraum des Zylinders der Brennkraftmaschine zugewandten Endbereich wenigstens eine, vorzugsweise mehrere Einspritzöffnungen 32 auf. Das Einspritzventilglied 28 weist an seinem dem Brennraum zugewandten Endbereich eine beispielsweise etwa kegelförmige Dichtfläche 34 auf, die mit einem im Ventilkörper 26 in dessen dem Brennraum zugewandtem Endbereich ausgebildeten Ventilsitz 36 zusammenwirkt, von dem oder nach dem die Einspritzöffnungen 32 abführen. Im Ventilkörper 26 ist zwischen dem Einspritzventilglied 28 und der Bohrung 30 zum Ventilsitz 36 hin ein Ringraum 38 vorhanden, der in seinem dem Ventilsitz 36 abgewandten Endbereich durch eine radiale Erweiterung der Bohrung 30 in einen das Einspritzventilglied 28 umgebenden Druckraum 40 übergeht. Das Einspritzventilglied 28 weist auf Höhe des Druckraums 40 durch eine Querschnittsverringerung eine Druckschulter 42 auf. Am dem Brennraum abgewandten Ende des Einspritzventilglieds 28 greift eine vorgespannte Schließfeder 44 an, durch die das Einspritzventilglied 28 zum Ventilsitz 36 hin gedrückt wird. Die Schließfeder 44 ist in einem Federraum 46 des Ventilkörpers 26 angeordnet, der sich an die Bohrung 30 anschließt.The fuel injection valve 12 has one with the Pump body 14 connected valve body 26, the may be formed in several parts, and in the one Injection valve member 28 in a bore 30th is guided longitudinally displaceable. The valve body 26 indicates its the combustion chamber of the cylinder of the internal combustion engine facing end region at least one, preferably a plurality Injection openings 32. The injection valve member 28 has at its the combustion chamber end facing a For example, about conical sealing surface 34, which with one in the valve body 26 in the combustion chamber facing End region formed valve seat 36 cooperates, from or after which the injection openings 32 dissipate. in the Valve body 26 is between the injection valve member 28 and the bore 30 to the valve seat 36 toward an annular space 38th present, in its the valve seat 36 facing away End region by a radial extension of the bore 30 in a pressure chamber 40 surrounding the injection valve member 28 passes. The injection valve member 28 has the height of the Pressure chamber 40 by a cross-sectional reduction a Pressure shoulder 42 on. At the end of the combustion chamber facing away from the Injector member 28 engages a biased Closing spring 44, through which the injection valve member 28th is pressed toward the valve seat 36. The closing spring 44 is arranged in a spring chamber 46 of the valve body 26, the adjoins the bore 30.

An den Federraum 46 schließt sich an dessen der Bohrung 30 abgewandtem Ende im Ventilkörper 26 eine weitere Bohrung 48 an, in der ein Steuerkolben 50 dicht geführt ist, der mit dem Einspritzventilglied 28 verbunden ist. Die Bohrung 48 ist im Durchmesser gestuft ausgebildet und weist einen zum Federraum 46 hin angeordneten Abschnitt 148 mit großem Durchmesser auf und einen dem Federraum 46 abgewandt angeordneten Abschnitt 248 mit kleinem Durchmesser auf. Der Steuerkolben 50 ist entsprechend im Durchmesser ebenfalls gestuft ausgebildet und weist einen im Bohrungsabschnitt 148 dicht geführten Bereich 150 mit großem Durchmesser auf und einen im Bohrungsabschnitt 248 dicht geführten Bereich 250 mit kleinem Durchmesser auf. Im Bohrungsabschnitt 248 wird durch die Stirnfläche des Bereichs 250 des Steuerkolbens 50 als bewegliche Wand ein Steuerdruckraum 52 begrenzt. Am Übergang zwischen den Bereichen 150,250 ist am Bereich 150 des Steuerkolbens 50 eine ringförmige Druckfläche 53 gebildet, mit der der Bereich 150 des Steuerkolbens 50 im Bohrungsabschnitt 148 einen weiteren Druckraum 54 begrenzt. Der Steuerkolben 50 ist über eine gegenüber diesem im Durchmesser kleinere Kolbenstange 51 mit dem Einspritzventilglied 28 verbunden. Der Steuerkolben 50 kann einstückig mit dem Einspritzventilglied 28 ausgebildet, ist jedoch aus Gründen der Montage vorzugsweise als separates Teil mit dem Einspritzventilglied 28 verbunden.At the spring chamber 46 connects to the bore 30th opposite end in the valve body 26, a further bore 48th in, in which a control piston 50 is tightly guided, with the injection valve member 28 is connected. The bore 48 is stepped in diameter and has a to Spring chamber 46 arranged portion 148 with a large Diameter on and facing away from the spring chamber 46 arranged portion 248 with a small diameter. Of the Control piston 50 is correspondingly in diameter as well stepped formed and has a in the bore portion 148th tightly guided area 150 with large diameter on and a tightly guided in the bore portion 248 area 250th with a small diameter. In the bore section 248 becomes through the end face of the area 250 of the control piston 50 limited as a movable wall, a control pressure chamber 52. At the Transition between ranges 150,250 is at range 150 of the control piston 50 an annular pressure surface 53rd formed with the area 150 of the control piston 50 in Bore portion 148 defines a further pressure chamber 54. The control piston 50 is one opposite this in the Diameter smaller piston rod 51 with the Injection valve member 28 connected. The control piston 50 can formed integrally with the injection valve member 28 is but preferably for reasons of assembly as a separate Part connected to the injection valve member 28.

Vom Pumpenarbeitsraum 22 führt durch den Pumpenkörper 14 und den Ventilkörper 26 ein Kanal 60 zum Druckraum 40 des Kraftstoffeinspritzventils 12. Vom Pumpenarbeitsraum 22 oder vom Kanal 60 führt ein Kanal 62 zum Steuerdruckraum 52. In den Steuerdruckraum 52 mündet außerdem ein Kanal 64, der eine Verbindung zu einem Entlastungsraum bildet, als der zumindest mittelbar der Kraftstoffvorratsbehälter 24 oder ein anderer Bereich dienen kann, in dem ein geringer Druck herrscht. Vom Pumpenarbeitsraum 22 oder vom Kanal 60 führt eine Verbindung 66 zu einem Entlastungsraum 24 ab, die durch ein erstes elektrisch betätigtes Steuerventil 68 gesteuert wird. Das Steuerventil 68 kann wie in Figur 1 dargestellt als 2/2-Wegeventil ausgebildet sein. Die Verbindung 64 des Steuerdruckraums 52 mit dem Entlastungsraum 24 wird durch ein zweites elektrisch betätigtes Steuerventil 70 gesteuert, das als 2/2-Wegeventil ausgebildet sein kann. In der Verbindung 62 des Steuerdruckraums 52 mit dem Pumpenarbeitsraum 22 ist eine Drosselstelle 63 vorgesehen und in der Verbindung des Steuerdruckraums 52 mit dem Entlastungsraum 24 ist eine Drosselstelle 65 vorgesehen. Durch geeignete Dimensionierung der Drosselstellen 63,65 kann der Zufluß von Kraftstoff aus dem Pumpenarbeitsraum 22 in den Steuerdruckraum 52 und der Abfluß von Kraftstoff aus dem Steuerdruckraum 52 in einem erforderlichen Umfang eingestellt werden. Ein ausreichender Zufluß von Kraftstoff in den Steuerdruckraum 52 ist für ein schnelles Schließen des Kraftstoffeinspritzventils 12 erforderlich und ein ausreichender Abfluß von Kraftstoff aus dem Steuerdruckraum 52 ist für ein schnelles Öffnen des Kraftstoffeinspritzventils 12 erforderlich. Die Steuerventile 68,70 können einen elektromagnetischen Aktor oder einen Piezoaktor aufweisen und werden durch eine elektronische Steuereinrichtung 72 angesteuert.From the pump working chamber 22 passes through the pump body 14 and the valve body 26, a channel 60 to the pressure chamber 40 of the Fuel injection valve 12. From the pump working chamber 22 or from channel 60, a channel 62 leads to the control pressure chamber 52. In the control pressure chamber 52 also opens a channel 64, the makes a connection to a relief room when the at least indirectly, the fuel tank 24 or another area may serve in which a low pressure prevails. From the pump chamber 22 or channel 60 leads a connection 66 to a discharge space 24 from, through a first electrically operated control valve 68 controlled becomes. The control valve 68 may be as shown in FIG be designed as a 2/2-way valve. The connection 64 of Control pressure chamber 52 with the discharge chamber 24 is through controlling a second electrically operated control valve 70, which can be designed as a 2/2-way valve. In the Connection 62 of the control pressure chamber 52 with the Pump work chamber 22 is a throttle point 63 is provided and in the connection of the control pressure chamber 52 with the Relief space 24, a throttle point 65 is provided. By suitable dimensioning of the throttle bodies 63,65 the inflow of fuel from the pump working space 22 in the control pressure chamber 52 and the outflow of fuel the control pressure chamber 52 to a required extent be set. A sufficient inflow of fuel in the control pressure chamber 52 is for a quick closing required and the fuel injection valve 12 sufficient drainage of fuel from the control pressure chamber 52 is for a quick opening of the Fuel injection valve 12 required. The Control valves 68,70 may be an electromagnetic actuator or have a piezoelectric actuator and are by a electronic control device 72 is controlled.

Der weitere Druckraum 54 weist eine Verbindung 56, beispielsweise in Form eines Kanals, mit dem Pumpenarbeitsraum 22 auf, die beispielsweise in den Kanal 60 münden kann. In der Verbindung 56 ist keine Drosselstelle vorhanden. Der weitere Druckraum 54 ist somit unter Umgehung der Drosselstelle 63 der Verbindung 62 des Steuerdruckraums 52 mit dem Pumpenarbeitsraum 22 direkt mit dem Pumepnarbeitsraum 22 verbunden und auf die Druckfläche 53 des Steuerkolbens 50 wirkt derselbe Druck wie im Pumpenarbeitsraum 22 und im Druckraum 40. Durch den im weiteren Druckraum 54 herrschenden Druck wird über die Druckfläche 53 und den Steuerkolben 50 eine die Schließfeder 44 unterstützende Kraft in Schließrichtung auf das Einspritzventilglied 28 erzeugt. Durch den im Steuerdruckraum 52 herrschenden Druck wird über die Stirnfläche des Steuerkolbens 50 ebenfalls eine die Schließfeder 44 unterstützende Kraft in Schließrichtung auf das Einspritzventilglied 28 erzeugt. Durch das zweite Steuerventil 70 wird der Druck im Steuerdruckraum 52 gesteuert, wobei sich bei geschlossenem Steuerventil 70 zumindest annähernd derselbe Druck im Steuerdruckraum 52 einstellt wie im Pumpenarbeitsraum 22 und wie im weiteren Druckraum 54 während sich bei geöffnetem Steuerventil 70 infolge der Verbindung mit dem Entlastungsraum 24 ein geringerer Druck im Steuerdruckraum 52 einstellt. Die auf das Einspritzventilglied 28 in der Summe wirkende Schließkraft ist somit abhängig von der Kraft der Schließfeder 44, von dem im Steuerdruckraum 52 herrschenden Druck, der durch das zweite Steuerventil 70 gesteuert wird, und von dem im weiteren Druckraum 54 herrschenden Druck, der gleich ist wie der im Pumpenarbeitsraum 22 herrschende Druck, der wiederum vom Förderhub des Pumpenkolbens 18 abhängig ist.The further pressure chamber 54 has a connection 56, for example, in the form of a channel, with the Pumping room 22, for example, in the channel 60 can lead. In the connection 56 is not a throttle point available. The additional pressure chamber 54 is thus bypassed the throttle point 63 of the connection 62 of the control pressure chamber 52 with the pump work chamber 22 directly to the Pumping room 22 connected and on the pressure surface 53rd the control piston 50 acts the same pressure as in Pump work chamber 22 and in the pressure chamber 40th By the im another pressure chamber 54 prevailing pressure is over the Pressure surface 53 and the control piston 50, a closing spring 44 supporting force in the closing direction on the Injection valve member 28 generated. By the im Control pressure chamber 52 prevailing pressure is over the End face of the control piston 50 also a the Closing spring 44 supporting force in the closing direction the injection valve member 28 generates. By the second Control valve 70, the pressure in the control pressure chamber 52nd controlled, wherein when the control valve 70 is closed at least approximately the same pressure in the control pressure chamber 52 adjusts as in the pump working chamber 22 and as in the other Pressure chamber 54 while with open control valve 70th as a result of the connection with the relief space 24 lower pressure in the control pressure chamber 52 sets. The on the injection valve member 28 acting in the sum Closing force is thus dependent on the force of Closing spring 44, of which prevails in the control pressure chamber 52 Pressure controlled by the second control valve 70 and of the pressure prevailing in the other pressure chamber 54 pressure, the is the same as that in the pump working chamber 22 prevailing Pressure, in turn, from the delivery stroke of the pump piston 18th is dependent.

In Figur 2 ist ausschnittsweise eine modifizierte Ausführung der Kraftstoffeinspritzeinrichtung dargestellt, bei der der grundsätzliche Aufbau gleich wie vorstehend beschrieben ist, jedoch die Druckfläche 53 an einem vom Steuerkolben 50 separaten Kolben 55 ausgebildet ist. Der Steuerkolben 50 weist dabei nur den im Bohrungsabschnitt 248 dicht geführten Steuerkolbenbereich 250 auf, der mit seiner Stirnfläche den Steuerdruckraum 52 begrenzt. Der Steuerkolben 50 ist über die Kolbenstange 51 mit dem Einspritzventilglied 28 verbunden. Der Kolben 55 ersetzt den Steuerkolbenbereich 150 der Ausführung gemäß Figur 1 und ist ebenfalls über eine Kolbenstange 57 mit dem Einspritzventilglied 28 verbunden, wobei die Kolbenstange 51 des Steuerkolbens 50 durch den Kolben 55 und dessen Kolbenstange 57 hindurchtritt. In Figure 2 is a detail of a modified embodiment the fuel injection device shown in which the basic structure is the same as described above, However, the pressure surface 53 at one of the control piston 50th separate piston 55 is formed. The control piston 50 in this case has only the tightly guided in the bore section 248 Control piston area 250, with its end face the Control pressure chamber 52 limited. The control piston 50 is over the piston rod 51 with the injection valve member 28th connected. The piston 55 replaces the spool area 150 the embodiment of Figure 1 and is also about a Piston rod 57 connected to the injection valve member 28, wherein the piston rod 51 of the control piston 50 through the Piston 55 and the piston rod 57 passes.

In Figur 3 ist ausschnittsweise eine modifizierte Ausführung der Kraftstoffeinspritzeinrichtung dargestellt, bei der der grundsätzliche Aufbau wiederum gleich wie bei der Ausführung gemäß Figur 1 ist, jedoch die Ausbildung des Steuerkolbens und die Anbindung des Steuerdruckraums 52 an den Pumpenarbeitsraum 22 modifiziert ist. Der Steuerkolben 50 weist dabei wiederum den im Bohrungsabschnitt 148 mit größerem Durchmesser dicht geführten Bereich 150 und den im Bohrungsabschnitt 248 mit kleinerem Durchmesser dicht geführten Bereich 250 auf. Durch die Stirnfläche des Steuerkolbenbereichs 250 wird der Steuerdruckraum 52 begrenzt und durch die ringförmige Druckfläche 53 des Steuerkolbenbereichs 150 wird der weitere Druckraum 54 begrenzt. Der weitere Druckraum 54 ist über die Verbindung 56 mit dem Kanal 60 und über diesen mit dem Pumpenarbeitsraum 22 verbunden. Im Steuerkolbenbereich 250 ist eine Verbindung 162, beispielsweise in Form einer Bohrung ausgebildet, durch die der Steuerdruckraum 52 mit dem weiteren Druckraum 54 verbunden ist. In der Verbindung 162 ist eine Drosselstelle 163 vorgesehen, die durch die Verbindung 162 selbst gebildet sein kann, wenn diese mit entsprechend kleinem Querschnitt ausgeführt ist. Vom Steuerdruckraum 52 führt die Verbindung 64 zum Entlastungsraum 24 ab, die durch das zweite Steuerventil 70 gesteuert wird und in der die Drosselstelle 65 vorgesehen ist. Abweichend zu der Ausführung gemäß Figur 1 weist der Bohrungsabschnitt 148 denselben Durchmesser auf wie der Federraum 46. Zur Trennung zwischen dem Bohrungsabschnitt 148 und dem Federraum 46 ist eine Zwischenscheibe 58 vorgesehen, an der sich die Schließfeder 44 im Federraum 46 abstützt. Zwischen der Kolbenstange 51 und dem Einspritzventilglied 28 kann eine Ausgleichsscheibe 59 angeordnet sein, mit der der Abstand zwischen dem Steuerkolben 50 und dem Einspritzventilglied 28 eingestellt werden kann. In Figure 3 is fragmentary a modified embodiment the fuel injection device shown in which the basic structure again the same as in the execution according to Figure 1, but the design of the control piston and the connection of the control pressure chamber 52 to the Pump working space 22 is modified. The control piston 50 in turn has the in the bore section 148 with larger diameter tightly guided area 150 and the im Bore portion 248 of smaller diameter tight guided area 250 on. Through the face of the Control piston area 250, the control pressure chamber 52nd limited and by the annular pressure surface 53 of the Control piston area 150, the further pressure chamber 54th limited. The further pressure chamber 54 is over the connection 56 with the channel 60 and over this with the Pump workspace 22 connected. In the control piston area 250 is a connection 162, for example in the form of a Hole formed through which the control pressure chamber 52 with the further pressure chamber 54 is connected. In the connection 162 is a throttle point 163 provided by the Compound 162 itself may be formed when using this is designed according to a small cross-section. from Control pressure chamber 52 leads the connection 64 to Relief space 24 from the second control valve 70th is controlled and provided in the throttle point 65 is. Notwithstanding the embodiment of Figure 1, the Bore portion 148 the same diameter as the Spring chamber 46. For the separation between the bore section 148 and the spring chamber 46 is an intermediate disc 58th provided at which the closing spring 44 in the spring chamber 46th supported. Between the piston rod 51 and the Injection valve member 28 may be a shim 59th be arranged with the distance between the Control piston 50 and the injection valve member 28 is set can be.

Nachfolgend wird die Funktion der Kraftstoffeinspritzeinrichtung erläutert. In Figur 4 ist der Verlauf des Druckes p an den Einspritzöffnungen 32 des Kraftstoffeinspritzventils 12 über der Zeit t während einem Einspritzzyklus dargestellt. Beim Saughub des Pumpenkolbens 18 wird diesem Kraftstoff aus dem Kraftstoffvorratsbehälter 24 zugeführt. Beim Förderhub des Pumpenkolbens 18 beginnt die Kraftstoffeinspritzung mit einer Voreinspritzung, wobei das erste Steuerventil 68 durch die Steuereinrichtung 72 geschlossen wird, so daß der Pumpenarbeitsraum 22 vom Entlastungsraum 24 getrennt ist. Durch die Steuereinrichtung 72 wird außerdem das zweite Steuerventil 70 geöffnet, so daß der Steuerdruckraum 52 mit dem Entlastungsraum 24 verbunden ist. In diesem Fall kann sich im Steuerdruckraum 52 kein Hochdruck aufbauen, da dieser zum Entlastungsraum 24 hin entlastet ist. Aus dem Pumpenarbeitsraum 22 kann jedoch eine geringe Kraftstoffmenge über die Drosselstellen 63 und 65 zum Entlastungsraum 24 abströmen, so daß sich im Pumpenarbeitsraum 22 nicht der volle Hochdruck aufbauen kann, wie er sich bei geschlossenem zweitem Steuerventil 70 aufbauen würde. Im weiteren Druckraum 54 herrscht derselbe Druck wie im Pumpenarbeitsraum 22 und im Druckraum 40. Wenn der Druck im Pumpenarbeitsraum 22 und damit im Druckraum 40 des Kraftstoffeinspritzventils 12 so groß ist, daß die durch diesen über die Druckschulter 42 auf das Einspritzventilglied 28 ausgeübte Druckkraft größer ist als die Summe der Kraft der Schließfeder 44, der auf den Steuerkolben 50 durch den im Steuerdruckraum 52 wirkenden Restdruck wirkenden Druckkraft und der durch den im weiteren Druckraum 54 herrschenden Druck über die Druckfläche 53 erzeugten Druckkraft, so bewegt sich das Einspritzventilglied 28 in Öffnungsrichtung 29 und gibt die wenigstens eine Einspritzöffnung 32 frei. Zur Beendigung der Voreinspritzung wird durch die Steuereinrichtung das zweite Steuerventil 70 geschlossen, so daß der Steuerdruckraum 52 vom Entlastungsraum 24 getrennt ist. Das erste Steuerventil 68 bleibt in seiner geschlossenen Stellung. Im Steuerdruckraum 52 baut sich dabei Hochdruck wie im Pumpenarbeitsraum 22 auf, so daß auf den Steuerkolben 50 eine große Druckkraft in Schließrichtung wirkt. Außerdem erhöht sich bei geschlossenem zweitem Steuerventil 70 der Druck im Pumpenarbeitsraum 22 und damit auch im weiteren Druckraum 54, so daß auch über die Druckfläche 53 eine erhöhte Kraft in Schließrichtung auf das Einspritzventilglied 28 erzeugt wird. Da nunmehr die auf das Einspritzventilglied 28 in Öffnungsrichtung 29 wirkende Kraft geringer ist als die Summe der Kraft der Schließfeder 44, der Druckkraft auf den Steuerkolben 50 und der Druckkraft auf die Druckfläche 53 schließt das Kraftstoffeinspritzventil 12. Die Voreinspritzung entspricht einer in Figur 4 mit I bezeichneten Einspritzphase.Below is the function of Fuel injection device explained. In Figure 4 is the Course of the pressure p at the injection openings 32 of the Fuel injection valve 12 over the time t during a Injection cycle shown. During the suction stroke of the pump piston 18 gets this fuel from the fuel tank 24 supplied. When the delivery stroke of the pump piston 18 begins the fuel injection with a pilot injection, wherein the first control valve 68 by the controller 72nd is closed, so that the pump chamber 22 from Relief space 24 is disconnected. By the control device 72, the second control valve 70 is also opened so that the control pressure chamber 52 connected to the discharge chamber 24 is. In this case, in the control pressure chamber 52 no Build high pressure, as this to the relief space 24 out is relieved. From the pump working chamber 22, however, a small amount of fuel through the throttle bodies 63 and 65th to discharge the discharge space 24, so that in the Pump work space 22 does not build up the full high pressure can, as he is with the second control valve 70 closed would build up. In the further pressure chamber 54, the same prevails Pressure as in the pump working chamber 22 and in the pressure chamber 40th If the pressure in the pump working chamber 22 and thus in the pressure chamber 40th of the fuel injection valve 12 is so large that through this on the pressure shoulder 42 on the Injection valve member 28 exerted pressure force is greater than the sum of the force of the closing spring 44, on the Control piston 50 by acting in the control pressure chamber 52 Residual pressure acting pressure force and by the further Pressure chamber 54 prevailing pressure on the pressure surface 53rd generated compressive force, so that moves Injection valve member 28 in the opening direction 29 and outputs the at least one injection port 32 free. To end the Pre-injection is the second by the controller Control valve 70 is closed, so that the control pressure chamber 52nd is separated from the discharge space 24. The first control valve 68 remains in its closed position. in the Control pressure chamber 52 builds up high pressure as in Pumping work chamber 22, so that on the control piston 50th a large pressure force acts in the closing direction. Furthermore increases with closed second control valve 70 of Pressure in the pump working chamber 22 and thus also in the other Pressure chamber 54, so that over the pressure surface 53 a increased force in the closing direction on the Injection valve member 28 is generated. Since now on the Injection valve member 28 acting in the opening direction 29 Force is less than the sum of the force of the closing spring 44, the pressure force on the control piston 50 and the Pressure force on the pressure surface 53 closes the Fuel injection valve 12. The pilot injection corresponds a designated in Figure 4 with I injection phase.

Für eine nachfolgende Haupteinspritzung, die einer in Figur 4 mit II bezeichneten Einspritzphase entspricht, wird das zweite Steuerventil 70 durch die Steuereinrichtung 72 geöffnet, so daß der Druck im Steuerdruckraum 52 sinkt. Das Kraftstoffeinspritzventil 12 öffnet dann infolge der reduzierten Druckkraft auf den Steuerkolben 50 und das Einspritzventilglied 28 bewegt sich über seinen maximalen Öffnungshub. Zur Begrenzung der Öffnungshubbewegung des Einspritzventilglieds 28 und des Steuerkolbens 50 kann die Druckfläche 53 an der am Übergang zwischen den Bohrungsabschnitten 148 und 248 gebildeten Ringschulter zur Anlage kommen. Für das Einspritzventilglied 28 kann jedoch auch ein anderer Hubanschlag zur Begrenzung von dessen Öffnungsbewegung vorgesehen sein. Bei geöffnetem zweitem Steuerventil 70 fließt eine geringe Kraftstoffmenge über die Drosselstellen 63,65 zum Entlastungsraum 24 ab, jedoch können die Drosselstellen 63,65 mit kleinem Durchflußquerschnitt ausgebildet werden, so daß die abströmende Kraftstoffmenge und die Verringerung des Drucks im Pumpenarbeitsraum 22 gering ist. For a subsequent main injection, the one in FIG 4 corresponds to II designated injection phase, the second control valve 70 by the controller 72nd opened, so that the pressure in the control pressure chamber 52 decreases. The Fuel injection valve 12 then opens as a result of reduced pressure force on the control piston 50 and the Injector member 28 moves above its maximum Opening stroke. To limit the opening stroke of the Injection valve member 28 and the control piston 50, the Pressure surface 53 at the transition between the Bore sections 148 and 248 formed annular shoulder for Plant come. However, for the injection valve member 28 may also another stroke stop to limit this Opening movement to be provided. When open second Control valve 70 flows a small amount of fuel over the Throttle 63.65 to the relief space 24 from, however can the throttle bodies 63,65 with small Flow area are formed so that the flowing fuel quantity and reducing the pressure in the pump working chamber 22 is low.

Zur Beendigung der Haupteinspritzung wird das erste Steuerventil 68 durch die Steuereinrichtung 72 in seine geöffnete Schaltstellung gebracht, so daß der Pumpenarbeitsraum 22 mit dem Entlastungsraum 24 verbunden ist und auf das Einspritzventilglied 28 in Öffnungsrichtung 29 nur noch eine geringe Druckkraft wirkt und das Kraftstoffeinspritzventil 12 bedingt durch die Kraft der Schließfeder 44, die durch den im Steuerdruckraum 52 herrschenden Restdruck auf den Steuerkolben 50 erzeugten Kraft und die durch den im weiteren Druckraum 54 auf die Druckfläche 53 erzeugte Kraft schließt. Das zweite Steuerventil 70 kann sich zur Beendigung der Haupteinspritzung in seiner geöffneten oder geschlossenen Stellung befinden.To finish the main injection, the first Control valve 68 by the controller 72 in his opened switch position, so that the Pump working space 22 connected to the discharge chamber 24 is and on the injection valve member 28 in the opening direction 29 only a small pressure force acts and that Fuel injection valve 12 due to the force of Closing spring 44, by the control pressure in the space 52nd prevailing residual pressure on the control piston 50 generated Force and by the in the further pressure chamber 54 on the Pressure surface 53 generated force closes. The second Control valve 70 may terminate the Main injection in its open or closed Position.

Bei den vorstehend erläuterten Ausführungen der Kraftstoffeinspritzeinrichtung kann zusätzlich vorgesehen werden, daß der Durchflußquerschnitt aus dem Steuerdruckraum 52 zum Entlastungsraum 24 durch den Steuerkolben 50 abhängig von dessen Hub variabel gesteuert wird. Durch den Steuerkolben 50 wird dabei in einer Hubstellung entsprechend der geschlossenen Stellung des Einspritzventilglieds 28 ein großer Durchflußquerschnitt freigegeben und in einer Hubstellung entsprechend der geöffneten Stellung des Einspritzventilglieds 28 ein geringer Durchflußquerschnitt freigegeben.In the above-mentioned embodiments of Fuel injection device can be additionally provided be that the flow area from the control pressure chamber 52 to the discharge chamber 24 by the control piston 50 dependent is variably controlled by its stroke. By the Control piston 50 is doing in a stroke position accordingly the closed position of the injection valve member 28 a large flow area released and in one Lift position corresponding to the open position of the Injection valve member 28 a small flow area Approved.

Claims (6)

  1. Fuel injection device for an internal combustion engine, with a high-pressure fuel pump (10) and with a fuel injection valve (12), connected to the latter, for each cylinder of the internal combustion engine, the high-pressure fuel pump (10) having a pump piston (18) driven in a lifting movement by the internal combustion engine and delimiting a pump working space (22), to which fuel is supplied from a fuel storage tank (24), the fuel injection valve (12) having a pressure space (40), connected to the pump working space (22), and an injection-valve member (28), by means of which at least one injection orifice (32) is controlled and which, acted upon by the pressure prevailing in the pressure space (40), can be moved in an opening direction (29), counter to a closing force, in order to release the at least one injection orifice (32), with a first control valve (68), by means of which a connection (66) of the pump working space (22) to a relief space (24) is controlled, and with a second control valve (70), by means of which a connection (64) of a control-pressure space (52) to a relief space (24) is controlled, the control-pressure space (52) being delimited by a control piston (50) which, acted upon by the pressure prevailing in the control-pressure space (52), acts on the injection-valve member (28) in a closing direction and which can be moved together with the injection-valve member (28), the control-pressure space (52) having a connection (62) to the pump working space (22), characterized in that, in the connections (62, 64) of the control-pressure space (52) to the pump working space (22) and to the relief space (24), a throttle point (63, 65) is provided in each case, and in that a further pressure space (54) is provided, which is connected to the pump working space (22) and which is delimited by a pressure surface (53), via which a further force on the injection-valve member (28) in the closing direction is generated.
  2. Fuel injection device according to Claim 1, characterized in that the pressure surface (53) is formed as an annular surface on a separate piston (55) surrounding the control piston (50).
  3. Fuel injection device according to Claim 1, characterized in that the pressure surface (53) is formed on the control piston (50) which is of stepped design in cross section, in that the control piston (50) delimits the control-pressure space (52) by means of the end face of a region (250) having a small cross section, and in that the pressure surface (53) is formed as an annular surface on a region (150) of large cross section of the control piston (50) at the transition to the region (250) having a small cross section.
  4. Fuel injection device according to one of Claims 1 to 3, characterized in that the further pressure space (54) is connected to the pump working space (22) directly, bypassing the throttle point (63) of the connection (62) of the control-pressure space (52) to the pump working space (22).
  5. Fuel injection device according to one of Claims 1 to 3, characterized in that the control-pressure space (52) is connected to the pump working space (22) via the further pressure space (54), and in that the throttle point (163) is arranged in the connection (162) between the control-pressure space (52) and the further pressure space (54).
  6. Fuel injection device according to Claim 5, characterized in that the connection (162) of the control-pressure space (52) to the further pressure space (54) takes place via at least one duct in the control piston (50).
EP02792635A 2002-02-12 2002-12-06 Fuel injection system for an internal combustion engine Expired - Lifetime EP1476655B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10205750 2002-02-12
DE10205750A DE10205750A1 (en) 2002-02-12 2002-02-12 Fuel injection device for an internal combustion engine
PCT/DE2002/004480 WO2003069154A1 (en) 2002-02-12 2002-12-06 Fuel injection system for an internal combustion engine

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EP1476655A1 EP1476655A1 (en) 2004-11-17
EP1476655B1 true EP1476655B1 (en) 2005-06-15

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US (1) US7025284B2 (en)
EP (1) EP1476655B1 (en)
JP (1) JP2005517859A (en)
DE (2) DE10205750A1 (en)
WO (1) WO2003069154A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1780406B1 (en) * 2005-10-25 2011-01-05 CRT Common Rail Technologies AG Injector for a fuel injection system and fuel injection system with such injector
FI123513B (en) * 2010-12-02 2013-06-14 Waertsilae Finland Oy Fuel supply unit, method for operating it and combustion engine

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1335126A1 (en) * 2002-02-12 2003-08-13 Robert Bosch Gmbh Fuel injection valve for a combustion engine
EP1335128A2 (en) * 2002-02-08 2003-08-13 Robert Bosch Gmbh High pressure hydraulic valve, in particularly for an internal combustion engine fuel injection apparatus

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9616521D0 (en) * 1996-08-06 1996-09-25 Lucas Ind Plc Injector
GB9820237D0 (en) * 1998-09-18 1998-11-11 Lucas Ind Plc Fuel injector
DE10031576C2 (en) * 2000-06-29 2002-07-11 Bosch Gmbh Robert Pressure controlled injector for injecting fuel
JP2002039031A (en) * 2000-07-10 2002-02-06 Robert Bosch Gmbh Fuel injector having rear setting pressure control element
DE10109610A1 (en) * 2001-02-28 2002-09-05 Bosch Gmbh Robert Fuel injection device for internal combustion engines
SE523482C2 (en) 2001-03-02 2004-04-20 Volvo Lastvagnar Ab Catalyst diesel engine
DE10123995A1 (en) * 2001-05-17 2002-11-21 Bosch Gmbh Robert Fuel injection device has third electrically operated control valve to control second connection between pump working cavity and relief cavity
DE10123993A1 (en) * 2001-05-17 2002-11-21 Bosch Gmbh Robert Fuel injection device has pressure maintaining valve between working cavity of pump and first control valve
DE10158659A1 (en) * 2001-11-30 2003-06-12 Bosch Gmbh Robert Fuel injection device for an internal combustion engine

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1335128A2 (en) * 2002-02-08 2003-08-13 Robert Bosch Gmbh High pressure hydraulic valve, in particularly for an internal combustion engine fuel injection apparatus
EP1335126A1 (en) * 2002-02-12 2003-08-13 Robert Bosch Gmbh Fuel injection valve for a combustion engine

Also Published As

Publication number Publication date
US7025284B2 (en) 2006-04-11
JP2005517859A (en) 2005-06-16
DE10205750A1 (en) 2003-08-21
EP1476655A1 (en) 2004-11-17
WO2003069154A1 (en) 2003-08-21
DE50203434D1 (en) 2005-07-21
US20040144365A1 (en) 2004-07-29

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