EP0828936A1 - Injection valve - Google Patents

Injection valve

Info

Publication number
EP0828936A1
EP0828936A1 EP96914853A EP96914853A EP0828936A1 EP 0828936 A1 EP0828936 A1 EP 0828936A1 EP 96914853 A EP96914853 A EP 96914853A EP 96914853 A EP96914853 A EP 96914853A EP 0828936 A1 EP0828936 A1 EP 0828936A1
Authority
EP
European Patent Office
Prior art keywords
nozzle needle
injection valve
piston
secondary piston
injection
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP96914853A
Other languages
German (de)
French (fr)
Other versions
EP0828936B1 (en
Inventor
Wendelin KLÜGL
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Publication of EP0828936A1 publication Critical patent/EP0828936A1/en
Application granted granted Critical
Publication of EP0828936B1 publication Critical patent/EP0828936B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • 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
    • F02M51/00—Fuel-injection apparatus characterised by being operated electrically
    • F02M51/005—Arrangement of electrical wires and connections, e.g. wire harness, sockets, plugs; Arrangement of electronic control circuits in or on fuel injection apparatus
    • 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
    • F02M47/06—Other fuel 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
    • F02M51/00—Fuel-injection apparatus characterised by being operated electrically
    • F02M51/06—Injectors peculiar thereto with means directly operating the valve needle
    • F02M51/0603—Injectors peculiar thereto with means directly operating the valve needle using piezoelectric or magnetostrictive operating means
    • 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
    • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
    • F02M2200/70—Linkage between actuator and actuated element, e.g. between piezoelectric actuator and needle valve or pump plunger
    • F02M2200/703—Linkage between actuator and actuated element, e.g. between piezoelectric actuator and needle valve or pump plunger hydraulic
    • F02M2200/704—Linkage between actuator and actuated element, e.g. between piezoelectric actuator and needle valve or pump plunger hydraulic with actuator and actuated element moving in different directions, e.g. in opposite directions

Definitions

  • the invention relates to an injection valve according to the preamble of claim 1.
  • Such an injection valve is known for example from EP-A 0 531 533.
  • This publication deals with a diesel injection device with a high-pressure system (common rail system), in which the fuel is supplied to a high-pressure accumulator via a high-pressure pump. This fuel, which is under high pressure, is then fed to the individual cylinders of a diesel engine via injection valves in accordance with a control.
  • the injection valves are each controlled by a solenoid valve, for example to enable individual injection times.
  • the injection valves should be able to be switched quickly at high injection pressures.
  • a pre-injection is difficult to use when using a solenoid valve, since the switching times of the solenoid valve are too long and the valve has to go through the full stroke in order to achieve reproducible conditions, for example the injection quantity.
  • the shaping of the injection rate i.e. Slow opening, but fastest closing of the nozzle needle, whereby the injection rate can be shaped according to a map, hardly possible.
  • the nozzle needle is actuated practically directly by the piezo actuator, the nozzle needle is actuated as quickly as possible.
  • the illustration shows an injection valve in section.
  • the injection valve shown in the figure consists of an elongated housing 5, on the lower end of which a union nut 3 is screwed on. With this cap nut 3, an intermediate washer 4 and a nozzle body 1, in which a nozzle needle 2 is guided, are held from the lower end of the housing 5.
  • the intermediate disk 4 and the nozzle body 1 have a central bore in which the nozzle needle 2 is guided so as to be displaceable in the axial direction.
  • a stepped plunger 7 is guided in the axial direction, which rests against the nozzle needle 2 at one end and is connected at the other end to a secondary piston 14 of the piezoelectric drive device.
  • a first pressure chamber 8 is provided, which is connected to a fuel inlet connection 10 via an inlet bore 9.
  • This high-pressure inlet connection 10 is also connected via an inlet bore 6 to a second pressure chamber 11, in the area of which the nozzle needle 2 is stepped, whereby a control surface for controlling the nozzle needle 2 is formed.
  • the tappet 7 is connected to a secondary piston 14 which is guided in a primary piston.
  • a piezo actuator 20 acts on the primary piston, which is mounted in a closure 21 and is opposite the actuator.
  • door housing 12 is sealed by an O-ring 22.
  • the closure 21 is secured in the axial direction by means of a securing ring 24. Electrical connections 23 lead to the actuator 20.
  • the piezo actuator 20 acts via the primary piston 19 on a plate spring 13. Furthermore, a spring 15 is provided in the recess of the secondary piston, which presses on an inner surface of the primary piston 19.
  • the injection valve also has a plurality of bores or spaces which are under low pressure.
  • This space 16 is connected to a return 25 via a leakage bore 27 and 29.
  • the piezo actuator 20 is arranged in a leakage space 26, which also opens into the return.
  • This space 26 is further connected via a relief bore 18 to a space 17 in which the spring 15 is arranged.
  • the working space 28 in the area of the plate spring 13 is always filled with fuel, which penetrates into this space due to the play between the upper area of the tappet 7 and the housing 5.
  • the effective areas for the pressure are designed so that the ring area on the plunger 7 is somewhat smaller than the ring area on the pressure shoulder of the nozzle needle 2. Therefore, even when the nozzle needle 2 is closed, there is always a resulting pressure force which acts upwards. but it is such that it is exceeded by the spring force of the spring 15, whereby the nozzle needle 2 is pressed securely onto its seat. No injection takes place in this position.
  • the effective diameters of the plunger 7 and the nozzle needle 2 mentioned are designed so that the spring 15 can be designed for acceptable, small forces.
  • the spring force must be so great that the nozzle needle 2 can be pressed onto the seat quickly enough at the end of the injection. It should be borne in mind that it acts upwards during the injection of the nozzle seat area.
  • a quick closing process of the nozzle needle has a favorable effect on the exhaust gas values of the internal combustion engine.
  • a piezo actuator offers the possibility of realizing faster switching operations than an electromagnet.
  • the small paths that a piezo actuator makes and therefore have to be translated are problematic.
  • the tappet 7 to the housing 5 and the secondary piston 14 to the primary piston 19 and the primary piston 19 to the actuator housing 12 are paired with one another with fits.
  • the fits only represent a gap seal, so that a small amount of fuel can constantly leak from the inlet 10 through the pressure chamber 8 along the tappet 7.
  • One L-corner portion goes in the direction of the nozzle needle 2 and must be fed to the return via the leakage holes 29 and 27.
  • the other leakage part enters the working space 28 and keeps it filled. Leakage fuel with excess flow flows along the secondary piston 14 via the relief bore 18 into the leakage space 26 and from there to the return 25.
  • the working space 28 is thus always full of fuel.
  • Disc spring 13 presses primary piston 19 with a defined preload against piezo actuator 20 into the starting position without play.
  • the plunger 7 In the starting position (rest position), the plunger 7 is pressed down by the spring 15 via the secondary piston 14 (no injection in this state).
  • the piezo actuator 20 When the piezo actuator 20 is energized, it expands downward and also moves the primary piston 19 downward against the force of the telescopic spring 13.
  • the volume of liquid in the working space 28 is displaced and guides the secondary piston 14 with the plunger upwards, as a result of which the nozzle needle 2 is moved upwards due to the resulting pressure force.
  • the start of injection is hereby triggered.
  • This construction of the piezo actuator with the two pistons ensures that the plunger 7 and thus the nozzle needle 2 are always moved from a defined starting position.
  • the return 25 is relieved to low pressure.
  • Piezo stacks are preferred as the piezo actuator, which also facilitate operation with relatively low voltages in the vehicle.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Fuel-Injection Apparatus (AREA)

Abstract

An injection valve with a needle nozzle (2) fitted in a valve housing (1), a fuel feed and a piezoelectric, hydraulically converted control device is designed to permit fast valve actuation in such a way that the needle nozzle (2) can be directly controlled via a pushrod (7) by a secondary piston (14) which can be operated by the primary piston (19) of the piezoelectric control device. This invention is applicable to diesel fuel injection systems.

Description

Beschreibungdescription
EinspritzventilInjector
Die Erfindung betrifft ein Einspritzventil nach dem Oberbe¬ griff des Patentanspruchs 1.The invention relates to an injection valve according to the preamble of claim 1.
Ein solches Einspritzventil ist beispielsweise durch die EP-A 0 531 533 bekannt. Diese Veröffentlichung behandelt eine Dieseleinspritzeinrichtung mit einem Hochdrucksystem (Common- Rail-System) , bei dem der Kraftstoff einem Hochdruckspeicher über eine Hochdruckpumpe zugeführt wird. Dieser unter hohem Druck stehende Kraftstoff wird dann entsprechend einer Steue¬ rung den einzelnen Zylindern eines Dieselmotors über Ein- spritzventile zugeführt. Dabei werden die Einspritzventile jeweils über ein Magnetventil angesteuert, um beispielsweise auch individuelle Einspritzzeiten zu ermöglichen.Such an injection valve is known for example from EP-A 0 531 533. This publication deals with a diesel injection device with a high-pressure system (common rail system), in which the fuel is supplied to a high-pressure accumulator via a high-pressure pump. This fuel, which is under high pressure, is then fed to the individual cylinders of a diesel engine via injection valves in accordance with a control. The injection valves are each controlled by a solenoid valve, for example to enable individual injection times.
Um insbesondere Einspritzventile zu erhalten, mit denen auch eine Voreinspritzung möglich ist, um damit Verbrauch, Abgas¬ werte, Geräusch usw. zu verbessern, sollen die Einspritzven¬ tile bei hohen Einspritzdrücken schnell schaltbar sein. Bei hohen Speicherdrücken ist bei Verwendung eines Magnetventils eine Voreinspritzung schwer möglich, da die Schaltzeiten des Magnetventils zu lang sind und der volle Hub des Ventils durchlaufen werden muß, damit reproduzierbare Bedingungen, beispielsweise die Einspritzmenge, erreicht werden. Außerdem ist die Formung der Einspritzrate, d.h. langsames Öffnen, jedoch schnellstes Schließen der Düsennadel, wobei die For- mung der Einspritzrate gemäß einem Kennfeld vorgenommen werden kann, kaum möglich.In order to obtain in particular injection valves with which a pre-injection is also possible in order to improve consumption, exhaust gas values, noise, etc., the injection valves should be able to be switched quickly at high injection pressures. At high accumulator pressures, a pre-injection is difficult to use when using a solenoid valve, since the switching times of the solenoid valve are too long and the valve has to go through the full stroke in order to achieve reproducible conditions, for example the injection quantity. In addition, the shaping of the injection rate, i.e. Slow opening, but fastest closing of the nozzle needle, whereby the injection rate can be shaped according to a map, hardly possible.
Es ist Aufgabe der vorliegenden Erfindung, ein Einspritzven¬ til bereitzustellen, das äußerst schnell schaltbar ist. Diese Aufgabe wird durch den Patentanspruch 1 gelöst. Vor¬ teilhafte Weiterbildungen sind in den ünteransprüchen gekenn¬ zeichnet.It is an object of the present invention to provide an injection valve which can be switched extremely quickly. This object is solved by claim 1. Advantageous further developments are characterized in the subordinate claims.
Da die Düsennadel durch den Piezoaktuator praktisch direkt betätigt wird, wird eine schnellstmögliche Betätigung der Düsennadel erzielt.Since the nozzle needle is actuated practically directly by the piezo actuator, the nozzle needle is actuated as quickly as possible.
Im folgenden wird die Erfindung anhand einer Abbildung näher erläutert.The invention is explained in more detail below with the aid of an illustration.
Die Abbildung zeigt ein Einspritzventil im Schnitt.The illustration shows an injection valve in section.
Das in der Abbildung gezeigte Einspritzventil besteht aus einem langgestreckten Gehäuse 5, auf dessem unteren Ende eine Überwurfmutter 3 aufgeschraubt ist. Mit dieser Oberwurfmutter 3 wird vom unteren Ende des Gehäuses 5 aus eine Zwischen¬ scheibe 4 und ein Düsenkörper 1, in welchem eine Düsennadel 2 geführt ist, gehalten. Die Zwischenscheibe 4 und der Düsen- körper 1 weisen eine Mittelbohrung auf, in der die Düsennadel 2 in axialer Richtung verschiebbar geführt ist. Im Gehäuse 5 ist in axialer Richtung ein abgestufter Stößel 7 geführt, der an einem Ende an der Düsennadel 2 anliegt und am anderen Ende mit einem Sekundärkolben 14 der piezoelektrischen Antriebs- einrichtung verbunden ist. Im Bereich der Abstufung des Stößels 7 ist ein erster Druckraum 8 vorgesehen, der über eine Zulaufbohrung 9 mit einem Kraftstoff-Zulaufanschluß 10 verbunden ist. Dieser Hochdruck-Zulaufanschluß 10 ist außer¬ dem über eine Zulaufbohrung 6 mit einem zweiten Druckraum 11 verbunden, in dessem Bereich die Düsennadel 2 abgestuft ist, wodurch eine Steuerfläche zur Steuerung der Düsennadel 2 gebildet wird.The injection valve shown in the figure consists of an elongated housing 5, on the lower end of which a union nut 3 is screwed on. With this cap nut 3, an intermediate washer 4 and a nozzle body 1, in which a nozzle needle 2 is guided, are held from the lower end of the housing 5. The intermediate disk 4 and the nozzle body 1 have a central bore in which the nozzle needle 2 is guided so as to be displaceable in the axial direction. In the housing 5, a stepped plunger 7 is guided in the axial direction, which rests against the nozzle needle 2 at one end and is connected at the other end to a secondary piston 14 of the piezoelectric drive device. In the area of the gradation of the tappet 7, a first pressure chamber 8 is provided, which is connected to a fuel inlet connection 10 via an inlet bore 9. This high-pressure inlet connection 10 is also connected via an inlet bore 6 to a second pressure chamber 11, in the area of which the nozzle needle 2 is stepped, whereby a control surface for controlling the nozzle needle 2 is formed.
Wie oben beschrieben steht der Stößel 7 mit einem Sekundär- kolben 14 in Verbindung, der in einem Primärkolben geführt ist. Auf den Primärkolben wirkt ein Piezoaktuator 20 ein, der in einem Verschluß 21 gelagert ist und gegenüber dem Aktua- torgehäuse 12 mittels eines O-Ringes 22 abgedichtet ist. In axialer Richtung ist der Verschluß 21 mittels eines Siche¬ rungsringes 24 gesichert. Elektrische Anschlüsse 23 sind zum Aktuator 20 geführt.As described above, the tappet 7 is connected to a secondary piston 14 which is guided in a primary piston. A piezo actuator 20 acts on the primary piston, which is mounted in a closure 21 and is opposite the actuator. door housing 12 is sealed by an O-ring 22. The closure 21 is secured in the axial direction by means of a securing ring 24. Electrical connections 23 lead to the actuator 20.
Der Piezoaktuator 20 wirkt' über den Primärkolben 19 auf eine Tellerfeder 13. Weiter ist in der Ausnehmung des Sekundärkol¬ bens eine Feder 15 vorgesehen, die auf eine Innenfläche des Primärkolbens 19 drückt.The piezo actuator 20 acts via the primary piston 19 on a plate spring 13. Furthermore, a spring 15 is provided in the recess of the secondary piston, which presses on an inner surface of the primary piston 19.
Das Einspritzventil weist außerdem mehrere unter Niederdruck stehende Bohrungen bzw. Räume auf. So befindet sich ein Raum 16 im Bereich zwischen dem Stößel 7 und einem Ende der Düsen¬ nadel 2. Dieser Raum 16 steht über eine Leckagebohrung 27 und 29 mit einem Rücklauf 25 in Verbindung. Der Piezoaktuator- 20 ist in einem Leckageraum 26 angeordnet, der ebenfalls in den Rücklauf mündet. Dieser Raum 26 steht weiter über eine Entla¬ stungsbohrung 18 mit einem Raum 17 in Verbindung, in welchem die Feder 15 angeordnet ist. Der Arbeitsraum 28 im Bereich der Tellerfeder 13 ist immer satt mit Kraftstoff gefüllt, der aufgrund des Spiels zwischen dem oberen Bereich des Stößels 7 und dem Gehäuse 5 in diesen Raum eindringt.The injection valve also has a plurality of bores or spaces which are under low pressure. There is a space 16 in the area between the plunger 7 and one end of the nozzle needle 2. This space 16 is connected to a return 25 via a leakage bore 27 and 29. The piezo actuator 20 is arranged in a leakage space 26, which also opens into the return. This space 26 is further connected via a relief bore 18 to a space 17 in which the spring 15 is arranged. The working space 28 in the area of the plate spring 13 is always filled with fuel, which penetrates into this space due to the play between the upper area of the tappet 7 and the housing 5.
Die wirksamen Flächen für den Druck sind bei geschlossener Düse so ausgelegt, daß die Ringfläche am Stößel 7 etwas kleiner ist als die Ringfläche an der Druckschulter der Düsennadel 2. Es verbleibt daher auch bei geschlossener Düsennadel 2 immer eine resultierende Druckkraft, die nach oben wirkt, aber so ist, daß sie von der Federkraft der Feder 15 übertroffen wird, wodurch die Düsennadel 2 sicher auf ihren Sitz gedrückt wird. In dieser Stellung erfolgt keine Einspritzung. Die genannten wirksamen Durchmesser des Stößels 7 und der Düsennadel 2 werden jedoch so ausgelegt, daß die Feder 15 auf vertretbare, möglichst kleine Kräfte ausgelegt werden kann. Die Federkraft muß jedoch so groß sein, daß die Düsennadel 2 bei Ende der Einspritzung schnell genug auf den Sitz gedrückt werden kann. Dabei ist zu berücksichtigen, daß sie während der Einspritzung der Düsensitzflache nach oben wirkt. Ein schneller Schließvorgang der Düsennadel wirkt sich günstig auf die Abgaswerte der Brennkraftmaschine aus.When the nozzle is closed, the effective areas for the pressure are designed so that the ring area on the plunger 7 is somewhat smaller than the ring area on the pressure shoulder of the nozzle needle 2. Therefore, even when the nozzle needle 2 is closed, there is always a resulting pressure force which acts upwards. but it is such that it is exceeded by the spring force of the spring 15, whereby the nozzle needle 2 is pressed securely onto its seat. No injection takes place in this position. However, the effective diameters of the plunger 7 and the nozzle needle 2 mentioned are designed so that the spring 15 can be designed for acceptable, small forces. However, the spring force must be so great that the nozzle needle 2 can be pressed onto the seat quickly enough at the end of the injection. It should be borne in mind that it acts upwards during the injection of the nozzle seat area. A quick closing process of the nozzle needle has a favorable effect on the exhaust gas values of the internal combustion engine.
Ein Piezoaktuator bietet die Möglichkeit, schnellere Schalt¬ vorgänge als ein Elektromagnet zu realisieren. Problematisch sind jedoch die kleinen Wege, die ein Piezoaktuator macht und deshalb übersetzt werden müssen.A piezo actuator offers the possibility of realizing faster switching operations than an electromagnet. However, the small paths that a piezo actuator makes and therefore have to be translated are problematic.
Die Funktionsweise des Piezoaktuators auf die Einspritzdüse ist folgende:The way the piezo actuator works on the injector is as follows:
Der Stößel 7 zum Gehäuse 5 und der Sekundärkolben 14 zum Primärkolben 19 sowie der Primärkolben 19 zum Aktuatorgehäuse 12 sind zueinander mit Passungen gepaart. Die Passungen stellen jedoch nur eine Spaltdichtung dar, so daß eine kleine Menge Kraftstoff ständig vom Zulauf 10 durch den Druckraum 8 am Stößel 7 entlang lecken kann. Der eine L-eckageanteil geht in Richtung Düsennadel 2 und muß über die Leckagebohrungen 29 und 27 dem Rücklauf zugeführt werden. Der andere Leckagean¬ teil gelangt in den Arbeitsraum 28 und hält diesen befüllt. Überschüssig durchströmter Leckagekraftstoff gelangt am Sekundärkolben 14 entlang über die Entlastungsbohrung 18 in den Leckageraum 26 und von dort zum Rücklauf 25. Der Arbeits- räum 28 ist somit immer satt mit Kraftstoff gefüllt. DieThe tappet 7 to the housing 5 and the secondary piston 14 to the primary piston 19 and the primary piston 19 to the actuator housing 12 are paired with one another with fits. However, the fits only represent a gap seal, so that a small amount of fuel can constantly leak from the inlet 10 through the pressure chamber 8 along the tappet 7. One L-corner portion goes in the direction of the nozzle needle 2 and must be fed to the return via the leakage holes 29 and 27. The other leakage part enters the working space 28 and keeps it filled. Leakage fuel with excess flow flows along the secondary piston 14 via the relief bore 18 into the leakage space 26 and from there to the return 25. The working space 28 is thus always full of fuel. The
Tellerfeder 13 drückt den Primärkolben 19 mit einer definier¬ ten Vorspannkraft gegen den Piezoaktuator 20 spielfrei in die Ausgangsstellung. In der Ausgangsstellung (Ruhestellung) wird der Stößel 7 von der Feder 15 über den Sekundärkolben 14 nach unten gedrückt (keine Einspritzung in diesem Zustand) . Bei Bestromen des Piezoaktuators 20 dehnt sich dieser nach unten aus und bewegt den Primärkolben 19 gegen die Kraft der Tel¬ lerfeder 13 ebenfalls nach unten. Das Flüssigkeitsvolumen im Arbeitsraum 28 wird verdrängt und führt den Sekundärkolben 14 mit dem Stößel nach oben, wodurch die Düsennadel 2 aufgrund der resultierenden Druckkraft nach oben bewegt wird. Hier¬ durch wird der Einspritzbeginn ausgelöst. Diese Konstruktion des Piezoaktuators mit den beiden Kolben gewährleistet, daß der Stößel 7 und damit die Düsennadel 2 immer aus einer definierten Ausgangslage bewegt werden. Für die Bewegung der Düsennadel 2 ist allein die Dynamik des Sekundärkolbens 14 mit dem' Stößel 7 maßgebend und nicht die Dynamik einer Hydraulik wie bei bekannten Systemen mit Venti¬ len. Alle Wärmedehnungen sind kompensiert. Der Arbeitsraum ist immer satt gefüllt. Der Piezoaktuator ist praktisch immer auf die gleiche Vorspannkraft gespannt.Disc spring 13 presses primary piston 19 with a defined preload against piezo actuator 20 into the starting position without play. In the starting position (rest position), the plunger 7 is pressed down by the spring 15 via the secondary piston 14 (no injection in this state). When the piezo actuator 20 is energized, it expands downward and also moves the primary piston 19 downward against the force of the telescopic spring 13. The volume of liquid in the working space 28 is displaced and guides the secondary piston 14 with the plunger upwards, as a result of which the nozzle needle 2 is moved upwards due to the resulting pressure force. The start of injection is hereby triggered. This construction of the piezo actuator with the two pistons ensures that the plunger 7 and thus the nozzle needle 2 are always moved from a defined starting position. For the movement of the nozzle needle 2, only the dynamics of the secondary piston 14 with the tappet 7 are decisive and not the dynamics of a hydraulic system as in known systems with valves. All thermal expansions are compensated. The workspace is always full. The piezo actuator is practically always under the same preload.
Der Rücklauf 25 ist auf Niederdruck entlastet. Als Piezoak¬ tuator werden Piezostacks favorisiert, die einen Betrieb mit relativ kleinen Spannungen auch im Fahrzeug erleichtern. The return 25 is relieved to low pressure. Piezo stacks are preferred as the piezo actuator, which also facilitate operation with relatively low voltages in the vehicle.

Claims

Patentansprüche claims
1. Einspritzventil für Kraftstoffeinspritzsysteme, mit:1. Injector for fuel injection systems, with:
- einer in einem Ventilgehäuse (1) angeordneten Düsennadel (2), die zumindest eine Einspritzδffnung des Einspritzventils öffnen und schließen kann, '- A nozzle needle (2) arranged in a valve housing (1), which can open and close at least one injection opening of the injection valve, '
- einem KraftstoffZulauf (10), der über jeweils einen Druck¬ raum (8,16) mit zwei unterschiedlich großen Steuerflächen der Düsennadel (2) und eines die Düsennadel (29 antreibenden Stößels(7) hydraulisch in Verbindung steht, einer piezoelektrischen Ansteuereinrichtung, die über einen Primär- und Sekundärkolben (14,19) hydraulisch über¬ setzt ist und die die Düsennadel (2) steuert, dadurch gekennzeichnet, daß - die Düsennadel (2) über den Stößel (7) durch den Sekundär¬ kolben (14) direkt steuerbar ist, der durch den Primärkolben (19) der Piezoansteuereinrichtung antreibbar ist.- A fuel feed (10), which is hydraulically connected via a pressure chamber (8, 16) with two differently sized control surfaces of the nozzle needle (2) and a tappet (7) driving the nozzle needle (29), a piezoelectric control device which is hydraulically over a primary and secondary piston (14,19) and controls the nozzle needle (2), characterized in that - the nozzle needle (2) via the plunger (7) through the secondary piston (14) directly is controllable, which can be driven by the primary piston (19) of the piezo control device.
2. Einspritzventil nach Anspruch 1, dadurch gekenn- zeichnet, daß der Sekundärkolben (14) fest mit dem Stößel (7) verbunden ist und gegebenüber dem Primärkolben (19) über eine Feder (15) vorgespannt ist.2. Injection valve according to claim 1, characterized in that the secondary piston (14) is fixedly connected to the tappet (7) and is biased over the primary piston (19) via a spring (15).
3. Einspritzventil nach Anspruch 1 und 2, dadurch ge- kennzeichnet, daß die Feder (15) den Sekundärkolben3. Injection valve according to claim 1 and 2, characterized in that the spring (15) the secondary piston
(14) in Richtung auf die Düsennadel (2) vorspannt.(14) in the direction of the nozzle needle (2).
4. Einspritzventil nach Anspruch 1, dadurch gekenn¬ zeichnet , daß die Steuerflächen durch Ringflächen gebil- det sind und die eine Ringfläche des Stößels (7) etwas klei¬ ner als die andere Ringfläche an der Druckschulter der Düsen¬ nadel (2) ist, so daß immer eine resultierende Kraft in Richtung auf die Antriebsvorrichtung verbleibt.4. Injection valve according to claim 1, characterized in that the control surfaces are formed by annular surfaces and the one annular surface of the tappet (7) is somewhat smaller than the other annular surface on the pressure shoulder of the nozzle needle (2). so that a resulting force always remains in the direction of the drive device.
5. Einspritzventil nach Anspruch 4, dadurch gekenn¬ zeichnet, daß die resultierende Kraft kleiner ist als die Kraft der Feder (15), so daß die Düsennadel (2) bei inaktiver Ansteuereinrichtung auf ihren Sitz gedrückt wird.5. Injector according to claim 4, characterized gekenn¬ characterized in that the resulting force is less than that Force of the spring (15) so that the nozzle needle (2) is pressed onto its seat when the control device is inactive.
6. Einspritzventil nach Anspruch 1, dadurch gekenn - zeichnet , daß der zwischen Primärkolben (19) und Sekun¬ därkolben (14) gebildete Arbeitsraum (28) über einen Leckage¬ strom des Einspritzventils immer gefüllt ist.6. Injection valve according to claim 1, characterized in that the working chamber (28) formed between primary piston (19) and secondary piston (14) is always filled via a leakage flow of the injection valve.
7. Einspritzventil nach Anspruch 6, dadurch gekenn - zeichnet , daß zwischen Stößel (7) und dem Gehäuse (5) sowie zwischen Primärkolben (19) und Sekundärkolben (14) sowie zwischen Primärkolben (19) und Gehäuse (12) Spalte vorgesehen sind, die so ausgelegt sind, daß dazwischen je¬ weils eine geringe Leckage stattfindet, so daß der Arbeits- räum (28) immer mit Flüssigkeit gefüllt ist, und daß bei -7. Injection valve according to claim 6, characterized in that gaps are provided between the plunger (7) and the housing (5) and between the primary piston (19) and secondary piston (14) and between the primary piston (19) and housing (12), which are designed in such a way that there is little leakage between them, so that the working space (28) is always filled with liquid, and that
Wärmedehnungen der Piezoaktuator eine spielausgeglichene, mit Druckspannung vorgespannte und eindeutig definierte Ausgangs- läge vor dem Anschalten einer elektrischen Spannung hat. Thermal expansion of the piezo actuator has a play-balanced, pre-stressed and clearly defined initial position before switching on an electrical voltage.
EP96914853A 1995-05-24 1996-05-11 Injection valve Expired - Lifetime EP0828936B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE19519191 1995-05-24
DE19519191A DE19519191C2 (en) 1995-05-24 1995-05-24 Injector
PCT/DE1996/000818 WO1996037698A1 (en) 1995-05-24 1996-05-11 Injection valve

Publications (2)

Publication Number Publication Date
EP0828936A1 true EP0828936A1 (en) 1998-03-18
EP0828936B1 EP0828936B1 (en) 2000-03-22

Family

ID=7762838

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96914853A Expired - Lifetime EP0828936B1 (en) 1995-05-24 1996-05-11 Injection valve

Country Status (4)

Country Link
EP (1) EP0828936B1 (en)
DE (2) DE19519191C2 (en)
ES (1) ES2145446T3 (en)
WO (1) WO1996037698A1 (en)

Families Citing this family (53)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5884848A (en) * 1997-05-09 1999-03-23 Cummins Engine Company, Inc. Fuel injector with piezoelectric and hydraulically actuated needle valve
US5979803A (en) * 1997-05-09 1999-11-09 Cummins Engine Company Fuel injector with pressure balanced needle valve
DE19726125C2 (en) * 1997-06-20 1999-04-15 Telefunken Microelectron Fuel injection method
DE19727992C2 (en) * 1997-07-01 1999-05-20 Siemens Ag Compensation element for compensation of temperature-related changes in length of electromechanical control systems
DE19742943C1 (en) * 1997-09-29 1999-04-22 Siemens Ag Coupling device between actuator and valve setting element
DE19817320C1 (en) 1998-04-18 1999-11-11 Daimler Chrysler Ag Injector for fuel injection systems
DE19839125C1 (en) * 1998-08-27 2000-04-20 Siemens Ag Device and method for dosing fluid
DE19843578A1 (en) * 1998-09-23 2000-03-30 Bosch Gmbh Robert Fuel injection valve especially for fuel injection installations of IC engines has longitudinal axis along which actuator exerts operating force displaced but parallel with respect to longitudinal axis of valve needle
DE19857338C1 (en) * 1998-12-11 2000-10-05 Siemens Ag Dosing arrangement for direct fuel injector
DE19858758C1 (en) 1998-12-18 2000-09-07 Siemens Ag Stroke transmission device and method
DE19907931A1 (en) * 1999-02-24 2000-09-14 Siemens Ag Dosing device for controlling combustion processes with common rail fuel injection system
DE19914714C2 (en) * 1999-03-31 2001-09-20 Siemens Ag Injector for storage fuel injection systems
EP1046809B1 (en) 1999-04-20 2005-08-10 Siemens Aktiengesellschaft Fluid metering device
DE19942816A1 (en) * 1999-09-08 2001-03-22 Daimler Chrysler Ag Injection valve has hydraulic conversion unit with hollow volume bounded by larger area membrane associated with control element and smaller area one associated with valve element
DE19956830C2 (en) * 1999-11-25 2002-07-18 Siemens Ag execution
DE10007735A1 (en) * 2000-02-19 2001-09-06 Daimler Chrysler Ag Fuel injection valve for IC engines has pressure-reducing throttle between high-pressure fuel in fuel chamber/line and lower pressure fuel in valve needle actuator area
DE10029629A1 (en) * 2000-06-15 2002-01-03 Bosch Gmbh Robert Fuel injection device for internal combustion engines
DE10042231B4 (en) * 2000-08-28 2004-09-30 Siemens Ag Injection valve for injecting fuel into an internal combustion engine and method for controlling the opening and closing process of a nozzle needle of an injection valve
DE10133265A1 (en) * 2001-07-09 2003-01-23 Bosch Gmbh Robert Fuel injection valve with piezoelectric or magnetostrictive actuator, has hydraulic coupling valve closure body and seat surface urged pressed together by spring
DE10326046A1 (en) * 2003-06-10 2004-12-30 Robert Bosch Gmbh Injection nozzle for internal combustion engines
DE112004001488D2 (en) * 2003-09-10 2006-07-27 Siemens Ag Injection valve for injecting fuel into an internal combustion engine
DE10343950B4 (en) * 2003-09-23 2014-12-31 Robert Bosch Gmbh Fuel injector
DE10353045A1 (en) * 2003-11-13 2005-06-23 Siemens Ag Fuel injection valve
DE102004005456A1 (en) 2004-02-04 2005-08-25 Robert Bosch Gmbh Fuel injector with direct-acting injection valve member
DE102004010668B4 (en) * 2004-03-04 2008-04-10 Sonplas Gmbh Method and device for processing a component
DE102004021920A1 (en) * 2004-05-04 2005-12-01 Robert Bosch Gmbh Fuel injector
DE102004031308B4 (en) * 2004-06-29 2013-05-23 Robert Bosch Gmbh Hydraulic coupler
DE102004035313A1 (en) 2004-07-21 2006-02-16 Robert Bosch Gmbh Fuel injector with two-stage translator
DE102004037124A1 (en) * 2004-07-30 2006-03-23 Robert Bosch Gmbh Common rail injector
DE102004044461A1 (en) * 2004-09-15 2006-03-30 Robert Bosch Gmbh injection
DE102004045393B4 (en) * 2004-09-18 2014-12-31 Robert Bosch Gmbh Fuel injector
DE102005015997A1 (en) * 2004-12-23 2006-07-13 Robert Bosch Gmbh Fuel injector with direct control of the injection valve member
DE102005026514B4 (en) * 2005-02-18 2008-12-24 Robert Bosch Gmbh injection
DE102005009148A1 (en) 2005-03-01 2006-09-07 Robert Bosch Gmbh Fuel injector with direct-acting injection valve member with double seat
DE102005015731A1 (en) * 2005-04-06 2006-10-12 Robert Bosch Gmbh Fuel injector with piezo actuator
DE102005016796A1 (en) * 2005-04-12 2006-10-19 Robert Bosch Gmbh Two-stage fuel injector
DE102005025141B3 (en) * 2005-06-01 2006-09-14 Siemens Ag Valve, e.g. for dosing liquid, has controllable transfer element of variable expansion in length in the transfer path between actuator and valve needle
DE102005036444A1 (en) * 2005-08-03 2007-02-08 Robert Bosch Gmbh injection
DE102005054739B4 (en) * 2005-11-17 2017-06-08 Robert Bosch Gmbh Injector for injecting fuel into combustion chambers of internal combustion engines, in particular piezoactuator-controlled common rail injector
DE102006019308A1 (en) * 2006-04-26 2007-10-31 Robert Bosch Gmbh Injector for fuel supply to internal combustion engine, especially in motor vehicle, has piezoactuator with foot on end remote from nozzle needle with sealing profile facing needle that contacts seal seat on injector body
DE102006026397A1 (en) * 2006-06-07 2007-12-13 Robert Bosch Gmbh Device for injecting fuel
DE102006027327B4 (en) 2006-06-13 2018-08-02 Robert Bosch Gmbh Fuel injector with direct needle control
DE102006036780A1 (en) * 2006-08-07 2008-02-21 Robert Bosch Gmbh Fuel injector with direct needle control and servo valve support
JP4333757B2 (en) 2007-03-13 2009-09-16 株式会社デンソー Fuel injection valve
DE102007019528B3 (en) * 2007-04-25 2008-09-11 Siemens Ag Pressure compensated injection valve with hydraulic converter has valve needle, actuator with different sized surfaces bounding hydraulic chambers; when actuator is operated hydraulic fluid passes between chambers via balancing chamber(s)
JP2009062910A (en) * 2007-09-07 2009-03-26 Denso Corp Fuel injection valve
EP2083158A1 (en) * 2008-01-22 2009-07-29 Delphi Technologies, Inc. Piezoelectrically actuated fuel injector and operating method thereof
DE102008002412A1 (en) 2008-06-13 2009-12-17 Robert Bosch Gmbh Fuel injector for injecting fuel into e.g. direct-injection diesel engine, has actuator coupled with nozzle needle, where actuator and head pistons on one side and needle and slave piston on another side exhibit different stroke axis
DE102008040086A1 (en) 2008-07-02 2010-01-07 Robert Bosch Gmbh Injector for injecting fuel into combustion chamber of internal combustion engine, has injection valve element for closing or releasing injection opening, and actuator for actuating injection valve element
DE102008035087B4 (en) * 2008-07-28 2015-02-12 Continental Automotive Gmbh Injector
DE102010040938A1 (en) * 2010-09-17 2012-03-22 Robert Bosch Gmbh fuel injector
DE102011088282A1 (en) * 2011-12-12 2013-06-13 Continental Automotive Gmbh Injector
GB201515892D0 (en) * 2015-09-08 2015-10-21 Delphi Int Operations Lux Srl Hydraulic lash adjuster arranged in a servo injector

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4841936A (en) * 1985-06-27 1989-06-27 Toyota Jidosha Kabushiki Kaisha Fuel injection control device of an internal combustion engine
DE3936619A1 (en) * 1989-11-03 1991-05-08 Man Nutzfahrzeuge Ag METHOD FOR INJECTING A FUEL INTO THE COMBUSTION CHAMBER OF AN AIR COMPRESSING, SELF-IGNITION ENGINE, AND APPARATUS FOR CARRYING OUT THIS METHOD
JPH0486367A (en) * 1990-07-30 1992-03-18 Aisin Seiki Co Ltd Fuel injection valve
DE4119467C2 (en) * 1991-06-13 1996-10-17 Daimler Benz Ag Device for force and stroke transmission or transmission operating according to the displacement principle
JPH05180114A (en) * 1991-12-27 1993-07-20 Aisin Seiki Co Ltd Fuel injection device
DE4306073C1 (en) * 1993-02-26 1994-06-01 Siemens Ag Metering system for dosing of fluids with injection valve for IC engine - has piston acting on closing unit, and spring with actuator acting on large dia. piston moving in cylinder

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9637698A1 *

Also Published As

Publication number Publication date
WO1996037698A1 (en) 1996-11-28
DE19519191C2 (en) 1997-04-10
EP0828936B1 (en) 2000-03-22
ES2145446T3 (en) 2000-07-01
DE59604782D1 (en) 2000-04-27
DE19519191A1 (en) 1996-12-19

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