EP1688611B1 - Fuel injector with direct needle control for an internal combustion engine - Google Patents

Fuel injector with direct needle control for an internal combustion engine Download PDF

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Publication number
EP1688611B1
EP1688611B1 EP05112500A EP05112500A EP1688611B1 EP 1688611 B1 EP1688611 B1 EP 1688611B1 EP 05112500 A EP05112500 A EP 05112500A EP 05112500 A EP05112500 A EP 05112500A EP 1688611 B1 EP1688611 B1 EP 1688611B1
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EP
European Patent Office
Prior art keywords
space
side pressure
coupler
piston
actuator
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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.)
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Application number
EP05112500A
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German (de)
French (fr)
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EP1688611A3 (en
EP1688611A2 (en
Inventor
Thomas Pauer
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Robert Bosch GmbH
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Robert Bosch GmbH
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Publication of EP1688611A3 publication Critical patent/EP1688611A3/en
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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
    • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
    • F02M63/0012—Valves
    • F02M63/0059—Arrangements of valve actuators
    • F02M63/0061—Single actuator acting on two or more valve bodies
    • 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
    • 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
    • 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
    • F02M2200/705—Linkage between actuator and actuated element, e.g. between piezoelectric actuator and needle valve or pump plunger hydraulic with means for filling or emptying hydraulic chamber, e.g. for compensating clearance or thermal expansion

Definitions

  • the invention relates to a fuel injector with direct needle control for an internal combustion engine according to the preamble of claim 1.
  • Fuel injectors with a so-called direct needle control are known. Such fuel injectors come without an intermediate control valve between an electrically actuated actuator and a nozzle needle. The power transmission between the actuator and the nozzle needle is realized by means of a pressure booster device.
  • piezoelectric actuators are suitable as actuators, which, depending on the energization in the closed state, have a direct or inverse control. In a direct control of the piezoelectric actuator is energized to open the nozzle needle, so that a linear expansion of the piezoelectric actuator realized by an oppressive movement opening of the injectors, which is amplified by the pressure booster device. In the closed state, the piezoelectric actuator has a smaller linear expansion.
  • the piezo actuator In an inverse control, the piezo actuator is energized in the closed state of the nozzle needle, so that the piezo actuator holds the nozzle needle closed in the state of its longitudinal expansion.
  • the piezoelectric actuator When the piezoactuator is actuated, the piezoelectric actuator is de-energized to initiate the injection process, so that pressure is released by a pulling movement of the piezoactuator in a control chamber of the pressure booster device. As a result, the lifting movement of the piezo actuator is hydraulically translated to open the nozzle needle.
  • the actuator In order to be able to open the injectors directly in fuel injectors with direct needle control by means of the actuator, the actuator must overcome a high opening force.
  • the required opening force to be applied by the actuator is due to the fact that the nozzle needle is pressurized with system pressure (pressure level in high-pressure accumulator) into its seat.
  • system pressure pressure level in high-pressure accumulator
  • the forces required to open the nozzle needle from its seat can be up to 400 Newton.
  • the nozzle needle performs a maximum stroke of several 100 microns.
  • the size of the actuator also referred to as the actuator volume, is essentially proportional to the opening force to be applied and the maximum stroke of the nozzle needle to be represented.
  • the fuel injector in this case has a guided in a nozzle body nozzle needle, which is exposed to a pressure shoulder a nozzle chamber and acts on a Düsennadeldichtsitzes, and a piezoelectric actuator and a hydraulic pressure booster on.
  • the pressure booster device comprises a coupler chamber, a pressure chamber and a control chamber, the coupler chamber and the pressure chamber being exposed to an actuator-side pressure booster piston connected to the piezo actuator.
  • the control chamber which is exposed to a nozzle needle-side pressure booster piston communicating with the nozzle needle, is hydraulically connected to the coupler chamber.
  • a pressing Aktorhub is generated, which moves the pressure booster piston in the direction of the pressure chamber, so that the pressure in the pressure chamber increases and the volume in the rear coupler space increases. This reduces the pressure in the coupler compartment.
  • the pressure reduction of the coupler chamber is transmitted to the hydraulically connected control chamber, so that the force acting on the nozzle needle closing force in the control chamber is reduced.
  • the simultaneously increasing pressure in the pressure chamber is transmitted to the hydraulically connected nozzle chamber, whereby the force acting on the nozzle needle opening force is supported.
  • the nozzle needle lifts off the nozzle needle seat and fuel is injected at the system pressure.
  • the nozzle needle moves in one stage according to the movement of the pressure booster piston in dependence on the pressure ratio between the coupler space and the control room.
  • the object of the invention is to provide a fuel injector with direct needle control and inverse control, which is simple and manages with a small size.
  • the fuel injector to realize a two-stage translation of the nozzle needle.
  • the object of the invention is achieved with a fuel injector with the characterizing measures of claim 1.
  • a particularly simple design can be achieved if the nozzle needle-side booster piston and the control piston in a stop position of the control piston in the coupler space facing common kopplerraum workede pressure surface forms, which forms a first pressure transmission ratio for a first gear ratio with a formed on the actuator-side pressure booster piston third kopplerraum workede pressure surface.
  • Appropriately, is to form a stop surface for the realization of the stop position of the control piston in the cylinder chamber, wherein the control piston is biased against the stop surface with a compression spring.
  • a second booster stage is realized in that a pressure compensation, which is transmitted from the outer rear space via the inner rear space to the control piston takes place, through which the control piston occupies a position raised from the stop surface, so that the annular surface pointing from the nozzle needle side pressure booster piston into the coupler space is effective Pressure surface forms a second pressure transmission ratio with the pressure surface formed by the actuator-side pressure booster piston and pointing into the coupler space, which realizes an opening stroke extending beyond the stroke of the actuator.
  • the fuel injector can be realized by guiding the actuator-side pressure booster piston and the nozzle needle-side pressure booster piston in a guide sleeve. It is also expedient if the actuator-side pressure booster piston is biased by a piston spring opposite to the closing direction of the nozzle needle and when the piston spring is supported on the guide sleeve.
  • FIG. 1 shows a schematic diagram of a fuel injector according to the invention in longitudinal section.
  • the fuel injector shown has an injector housing 10 with a nozzle body 11 which projects with its lower end into a combustion chamber of an internal combustion engine. Between injector housing 10 and nozzle body 11 is a nozzle needle guide 12 with a Guide bore 13 is arranged. In the guide bore 13, a nozzle needle 14 is guided axially displaceable. Between the tip of the nozzle needle 14 and the nozzle body 11 is a sealing seat 15 is formed, which are formed in the nozzle body 11 and projecting into the combustion chamber injection nozzles 16 downstream.
  • the sealing seat 15 is preceded by a high-pressure chamber 17 is formed.
  • the injector housing 10 has an actuator receiving space 18 in an upper area, to which a fuel inlet 19 is connected.
  • a piezoelectric actuator 20 is arranged in Aktorfactraum 18 .
  • the fuel inlet 19 is connected to a high-pressure system, for example, to a common rail system of a diesel injection device.
  • a connecting bore 21 passes through the nozzle needle guide 12, so that the fuel introduced via the fuel feed 19 into the actuator receiving space 18 is conducted at high pressure into the high-pressure space 17 assigned to the nozzle needle 14.
  • the actuator receiving space 18 merges into a receiving space 22 for a pressure booster 30.
  • the pressure booster 30 has an actuator-side pressure booster piston 31, a nozzle needle side pressure booster piston 32, a coupler space 33, a control piston 34, a guide sleeve 35, an inner rear space 36 and an outer rear space 37.
  • the actuator-side pressure booster piston 31 and the nozzle needle-side pressure booster piston 32 are guided in the guide sleeve 35.
  • a piston spring 38 is arranged, which presses a formed on the guide sleeve 35 sealing surface 39 against an opening formed on the nozzle needle guide 12 face 23.
  • the piston spring 38 also biases the actuator-side pressure booster piston 31 against the piezo-actuator 20.
  • a closing spring 25 which presses the nozzle needle 14 in the closing direction, engages on the nozzle needle 14.
  • the nozzle needle-side pressure booster piston 32 is designed with an inner cylinder chamber 40 in which the control piston 34 is guided axially movable. Towards the coupler space 33, the inner cylinder space 40 is provided with a circular opening 41, so that a first, annular, coupler-space-side pressure surface 42 on the nozzle needle-side pressure booster piston 32 forms toward the coupler space 33.
  • the diameter of the cylinder chamber 40 is greater than the diameter of the opening 41, so that at the opening 41 in the cylinder chamber 40 facing annular abutment surface 43 for the control piston 34 is formed.
  • the cylinder chamber 40 and the control piston 34 are designed so that the control piston 34 in the cylinder chamber 40 at the side facing away from the coupler chamber 33 side with a rear-side pressure surface 48 in the inner rear space 36 has.
  • a further compression spring 44 is arranged, which presses the control piston 34 against the stop surface 43.
  • the control piston 34 has a second, circular, coupler space-side pressure surface 45, which points into the coupler space 40 and corresponds to the cross-section of the opening 41.
  • the actuator-side pressure booster piston 31 has a third pressure surface 46 on the coupler-space side in the coupler space 33.
  • a stepped piston To the tip of the nozzle needle 14 toward the nozzle needle-side booster piston 32 is designed as a stepped piston with an annular surface 24 which is associated with the outer rear space 37 within the guide sleeve 35.
  • the outer rear space 37 and the inner rear space 36 are connected via a hydraulic connection 47, for example a bore.
  • the sealing seat 15 of the nozzle needle 16 is closed.
  • the system pressure reached via the fuel supply 19 into the actuator receiving space 18 and into the pressure chamber 17 is equal in all pressure chambers. In this case, there are leakage gaps on the guide sleeve 35, so that the system pressure can reach both into the coupler space 33 and into the outer rear space 37 and via the connection 47 into the inner rear space 36.
  • the pressure booster 30 is pressure balanced.
  • the actuator 20 is supplied with a voltage and thereby elongated in its energized state in its vertical direction.
  • the system pressure applied in the coupler chamber 33 acts in the closing direction on the nozzle needle-side pressure-translating piston 32, so that in this state of the piezo-actuator 20, the sealing seat 15 of the nozzle needle 14 is closed.
  • the length of the piezoelectric actuator 20 in the vertical direction is likewise reduced. Due to the biased by the piston spring 38 in the direction of the piezo-actuator 20 actuator-side pressure booster piston 31 this is also moved in the vertical direction due to the reduced vertical length of the piezo-actuator 20. As a result of this outwardly directed pulling movement of the actuator-side pressure booster piston 31 in the guide sleeve 35, the volume in the coupler space 33 increases, whereby there takes place a pressure reduction which delivers an opening pressure p ö1 for a first stage for opening the nozzle needle 14.
  • the pressure ratio for the first opening stage is formed by the ratio of the actuator-side pressure booster piston 31 formed third kopplerraum detaileden pressure surface 46 to the common kopplerraum subjecten pressure surface, wherein the common kopplerraum dealte pressure surface is composed of the first annular kopplerraum technologyen pressure surface 42 of the nozzle needle side pressure booster piston 32 and the second, circular kopplerraum disorderen pressure surface 45 of the control piston 34.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fuel-Injection Apparatus (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)

Abstract

The injector has a needle pressure boosting piston (32) with a control piston (34) axially guided in a cylindrical chamber. Coupler and differential chamber pressure surfaces are exposed to coupler and inner differential pressure chambers, respectively. The piston (32) is associated with an outer differential pressure chamber that communicates via a hydraulic connection with the inner chamber acting on the piston (34).

Description

Die Erfindung betrifft einen Kraftstoffinjektor mit direkter Nadelsteuerung für eine Brennkraftmaschine nach dem Oberbegriff des Anspruchs 1.The invention relates to a fuel injector with direct needle control for an internal combustion engine according to the preamble of claim 1.

Stand der TechnikState of the art

Kraftstoffmjektoren mit einer sogenannten direkten Nadelsteuerung sind bekannt. Derartige Kraftstoffinjektoren kommen ohne ein zwischengeschaltetes Steuerventil zwischen einem elektrisch angesteuerten Aktor und einer Düsennadel aus. Die Kraftübertragung zwischen dem Aktor und der Düsennadel wird dabei mittels einer Druckübersetzungseinrichtung realisiert. Als Aktoren eignen sich dabei insbesondere piezoelektrische Aktoren, die je nach Bestromung im geschlossenen Zustand eine direkte oder inverse Ansteuerung aufweisen. Bei einer direkten Ansteuerung wird der Piezo-Aktor zum Öffnen der Düsennadel bestromt, so dass eine Längenausdehnung des Piezo-Aktors durch eine drückende Bewegung ein Öffnen der Einspritzdüsen realisiert, die durch die Druckübersetzungseinrichtung verstärkt wird. Im geschlossenen Zustand weist dabei der Piezo-Aktor eine geringere Längenausdehnung auf. Bei einer inversen Ansteuerung ist der Piezo-Aktor im geschlossenen Zustand der Düsennadel bestromt, so dass der Piezo-Aktor im Zustand seiner Längenausdehnung die Düsennadel geschlossen hält. Beim Ansteuern des Piezo-Aktors wird zum Einleiten des Einspritzvorganges der Piezo-Aktor stromlos geschaltet, so dass durch eine ziehende Bewegung des Piezo-Aktors in einem Steuerraum der Druckübersetzungseinrichtung eine Druckentlastung stattfindet. Dadurch wird die Hubbewegung des Piezo-Aktors zum Öffnen der Düsennadel hydraulisch übersetzt.Fuel injectors with a so-called direct needle control are known. Such fuel injectors come without an intermediate control valve between an electrically actuated actuator and a nozzle needle. The power transmission between the actuator and the nozzle needle is realized by means of a pressure booster device. In particular, piezoelectric actuators are suitable as actuators, which, depending on the energization in the closed state, have a direct or inverse control. In a direct control of the piezoelectric actuator is energized to open the nozzle needle, so that a linear expansion of the piezoelectric actuator realized by an oppressive movement opening of the injectors, which is amplified by the pressure booster device. In the closed state, the piezoelectric actuator has a smaller linear expansion. In an inverse control, the piezo actuator is energized in the closed state of the nozzle needle, so that the piezo actuator holds the nozzle needle closed in the state of its longitudinal expansion. When the piezoactuator is actuated, the piezoelectric actuator is de-energized to initiate the injection process, so that pressure is released by a pulling movement of the piezoactuator in a control chamber of the pressure booster device. As a result, the lifting movement of the piezo actuator is hydraulically translated to open the nozzle needle.

Um bei Kraftstoffinjektoren mit direkter Nadelsteuerung die Einspritzdüsen mittels des Aktors direkt öffnen zu können, muss der Aktor eine hohe Öffnungskraft überwinden. Die erforderliche Öffnungskraft, die durch den Aktor aufzubringen ist, findet ihre Ursache darin, weil die Düsennadel mit Systemdruck (Druckniveau in Hochdruckspeicher) beaufschlagt in ihren Sitz gedrückt wird. Die zum Öffnen der Düsennadel aus ihrem Sitz erforderlichen Kräfte können bis zu 400 Newton betragen. Um für einen ausreichenden Kraftstofffluss bei vollständig geöffneten Einspritzdüsen eine Einspritzung in den Brennraum einer selbstzündenden Verbrennungskraftmaschine zu sorgen, ist es außerdem erforderlich, dass die Düsennadel einen maximalen Hubweg von mehreren 100 µm ausführt. Zwar lässt sich durch Integration einer hydraulischen Übersetzung das Längen/Durchmesserverhältnis des Piezo-Aktors variieren, jedoch ist die Baugröße des Aktors, auch als Aktorvolumen bezeichnet, im Wesentlichen proportional zur aufzubringenden Öffnungskraft und dem darzustellenden maximalen Hubweg der Düsennadel.In order to be able to open the injectors directly in fuel injectors with direct needle control by means of the actuator, the actuator must overcome a high opening force. The required opening force to be applied by the actuator is due to the fact that the nozzle needle is pressurized with system pressure (pressure level in high-pressure accumulator) into its seat. The forces required to open the nozzle needle from its seat can be up to 400 Newton. In order to ensure sufficient fuel flow at fully open injectors injection into the combustion chamber of a self-igniting internal combustion engine, it is also necessary that the nozzle needle performs a maximum stroke of several 100 microns. Although the length / diameter ratio of the piezoelectric actuator can be varied by integrating a hydraulic ratio, the size of the actuator, also referred to as the actuator volume, is essentially proportional to the opening force to be applied and the maximum stroke of the nozzle needle to be represented.

Aus DE 103 26 046 A1 sind verschiedene Ausführungsvarianten von Kraftstoffinjektoren mit einer direkten Nadelsteuerung bekannt. Der Kraftstoffinjektor weist dabei eine in einem Düsenkörper geführte Düsennadel, die mit einer Druckschulter einem Düsenraum ausgesetzt ist und auf einen Düsennadeldichtsitzes einwirkt, sowie einen Piezo-Aktor und eine hydraulische Druckübersetzungseinrichtung auf. Die Druckübersetzungseinrichtung umfasst einen Kopplerraum, einen Druckraum sowie einen Steuerraum, wobei dem Kopplerraum und dem Druckraum ein mit dem Piezo-Aktor in Verbindung stehender aktorseitiger Druckübersetzerkolben ausgesetzt ist. Der Steuerraum, dem ein mit der Düsennadel in Verbindung stehender düsennadelseitiger Druckübersetzerkolben ausgesetzt ist, ist mit dem Kopplerraum hydraulisch verbunden. Bei Betätigung des Piezo-Aktors wird ein drückender Aktorhub erzeugt, der den Druckübersetzerkolben in Richtung Druckraum bewegt, so dass der Druck im Druckraum ansteigt und sich das Volumen im rückwärtigen Kopplerraum vergrößert. Dadurch wird der Druck im Kopplerraum reduziert. Die Druckreduzierung des Kopplerraums wird auf den hydraulisch verbundenen Steuerraum übertragen, so dass sich die auf die Düsennadel wirkende Schließkraft im Steuerraum verringert. Der sich gleichzeitig erhöhende Druck im Druckraum wird auf den hydraulisch verbundenen Düsenraum übertragen, wodurch die auf die Düsennadel wirkende Öffnungskraft unterstützt wird. Die Düsennadel hebt vom Düsennadelsitz ab und Kraftstoff wird mit dem Systemdruck eingespritzt. Die Düsennadel bewegt sich dabei einstufig gemäß der Bewegung des Druckübersetzerkolbens in Abhängigkeit von der Druckübersetzung zwischen Kopplerraum und Steuerraum.Out DE 103 26 046 A1 Different variants of fuel injectors with a direct needle control are known. The fuel injector in this case has a guided in a nozzle body nozzle needle, which is exposed to a pressure shoulder a nozzle chamber and acts on a Düsennadeldichtsitzes, and a piezoelectric actuator and a hydraulic pressure booster on. The pressure booster device comprises a coupler chamber, a pressure chamber and a control chamber, the coupler chamber and the pressure chamber being exposed to an actuator-side pressure booster piston connected to the piezo actuator. The control chamber, which is exposed to a nozzle needle-side pressure booster piston communicating with the nozzle needle, is hydraulically connected to the coupler chamber. Upon actuation of the piezo actuator, a pressing Aktorhub is generated, which moves the pressure booster piston in the direction of the pressure chamber, so that the pressure in the pressure chamber increases and the volume in the rear coupler space increases. This reduces the pressure in the coupler compartment. The pressure reduction of the coupler chamber is transmitted to the hydraulically connected control chamber, so that the force acting on the nozzle needle closing force in the control chamber is reduced. The simultaneously increasing pressure in the pressure chamber is transmitted to the hydraulically connected nozzle chamber, whereby the force acting on the nozzle needle opening force is supported. The nozzle needle lifts off the nozzle needle seat and fuel is injected at the system pressure. The nozzle needle moves in one stage according to the movement of the pressure booster piston in dependence on the pressure ratio between the coupler space and the control room.

Aufgabe der Erfindung ist es, einen Kraftstoffinjektor mit direkter Nadelsteuerung und inverser Ansteuerung zu schaffen, der einfach aufgebaut ist und mit einer geringen Baugröße auskommt. Darüber hinaus soll der Kraftstoffinjektor eine zweistufige Übersetzung der Düsennadel realisieren.The object of the invention is to provide a fuel injector with direct needle control and inverse control, which is simple and manages with a small size. In addition, the fuel injector to realize a two-stage translation of the nozzle needle.

Vorteile der ErfindungAdvantages of the invention

Die Aufgabe der Erfindung wird mit einem Kraftstoffinjektor mit den kennzeichnenden Maßnahmen des Anspruchs 1 gelöst. Durch die Anordnung eines innerhalb des düsennadelseitigen Druckübersetzerkolbens axial geführten Steuerkolbens ist ein Kraftstoffinjektor mit kompakter und geringer Baugröße realisierbar, der mit wenig beweglichen Bauteilen zur Realisierung des erforderlichen Druckübersetzungsverhältnisses für eine zweistufige Übersetzung auskommt.The object of the invention is achieved with a fuel injector with the characterizing measures of claim 1. By arranging an axially guided within the nozzle needle-side pressure booster piston control piston, a fuel injector with a compact and small size can be realized, with little moving components to achieve the required pressure transmission ratio for a two-stage translation.

Vorteilhafte Weiterbildungen der Erfindung sind durch die Maßnahmen der Unteransprüche möglich. Eine besonders einfache Bauform ist erzielbar, wenn der düsennadelseitige Übersetzerkolben und der Steuerkolben in einer Anschlagposition des Steuerkolbens eine in den Kopplerraum weisende gemeinsame kopplerraumseitige Druckfläche ausbildet, die mit einer am aktorseitigen Druckübersetzerkolben ausgebildeten dritten kopplerraumseitige Druckfläche ein erstes Druckübersetzungsverhältnis für eine erste Übersetzungsstufe bildet. Zweckmäßigerweise ist dabei, zur Realisierung der Anschlagposition des Steuerkolbens im Zylinderraum eine Anschlagfläche auszubilden, wobei der Steuerkolben gegen die Anschlagfläche mit einer Druckfeder vorgespannt ist. Die Einleitung einer zweiten Übersetzerstufe wird dadurch realisiert, dass ein vom äußeren Rückraum über den inneren Rückraum auf den Steuerkolben übertragener Druckausgleich stattfindet, durch den der Steuerkolben eine von der Anschlagfläche abgehobene Position einnimmt, so dass die vom düsennadelseitigen Druckübersetzerkolben in den Kopplerraum weisende Ringfläche als wirksame Druckfläche mit der vom aktorseitigen Druckübersetzerkolben ausgebildeten und in den Kopplerraum weisenden Druckfläche ein zweites Druckübersetzungsverhältnis bildet, das einen über den Hub des Aktors hinausgehenden Öffnungshub realisiert. Fertigungstechnisch zweckmäßig realisierbar ist der Kraftstoffmjektor, indem der aktorseitige Druckübersetzerkolben und der düsennadelseitige Druckübersetzerkolben in einer Führungshülse geführt sind. Zweckmäßig ist außerdem, wenn der aktorseitige Druckübersetzerkolben mittels einer Kolbenfeder entgegengesetzt zur Schließrichtung der Düsennadel vorgespannt ist und wenn sich die Kolbenfeder an der Führungshülse abstützt.Advantageous developments of the invention are possible by the measures of the subclaims. A particularly simple design can be achieved if the nozzle needle-side booster piston and the control piston in a stop position of the control piston in the coupler space facing common kopplerraumseitige pressure surface forms, which forms a first pressure transmission ratio for a first gear ratio with a formed on the actuator-side pressure booster piston third kopplerraumseitige pressure surface. Appropriately, is to form a stop surface for the realization of the stop position of the control piston in the cylinder chamber, wherein the control piston is biased against the stop surface with a compression spring. The introduction of a second booster stage is realized in that a pressure compensation, which is transmitted from the outer rear space via the inner rear space to the control piston takes place, through which the control piston occupies a position raised from the stop surface, so that the annular surface pointing from the nozzle needle side pressure booster piston into the coupler space is effective Pressure surface forms a second pressure transmission ratio with the pressure surface formed by the actuator-side pressure booster piston and pointing into the coupler space, which realizes an opening stroke extending beyond the stroke of the actuator. In terms of manufacturing technology, the fuel injector can be realized by guiding the actuator-side pressure booster piston and the nozzle needle-side pressure booster piston in a guide sleeve. It is also expedient if the actuator-side pressure booster piston is biased by a piston spring opposite to the closing direction of the nozzle needle and when the piston spring is supported on the guide sleeve.

Ausführungsbeispielembodiment

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Figur 1 zeigt eine Prinzipdarstellung eines erfindungsgemäßen Kraftstoffinjektors im Längsschnitt.An embodiment of the invention is illustrated in the drawing and explained in more detail in the following description. FIG. 1 shows a schematic diagram of a fuel injector according to the invention in longitudinal section.

Der dargestellte Kraftstoffinjektor weist ein Injektorgehäuse 10 mit einem Düsenkörper 11 auf, der mit seinem unteren Ende in einen Brennraum einer Brennkraftmaschine ragt. Zwischen Injektorgehäuse 10 und Düsenkörper 11 ist eine Düsennadelführung 12 mit einer Führungsbohrung 13 angeordnet. In der Führungsbohrung 13 ist eine Düsennadel 14 axial verschiebbar geführt. Zwischen der Spitze der Düsennadel 14 und dem Düsenkörper 11 ist ein Dichtsitz 15 ausgebildet, dem im Düsenkörper 11 ausgebildete und in den Brennraum hineinragende Einspritzdüsen 16 nachgeschaltet sind.The fuel injector shown has an injector housing 10 with a nozzle body 11 which projects with its lower end into a combustion chamber of an internal combustion engine. Between injector housing 10 and nozzle body 11 is a nozzle needle guide 12 with a Guide bore 13 is arranged. In the guide bore 13, a nozzle needle 14 is guided axially displaceable. Between the tip of the nozzle needle 14 and the nozzle body 11 is a sealing seat 15 is formed, which are formed in the nozzle body 11 and projecting into the combustion chamber injection nozzles 16 downstream.

Im Düsenkörper 11 ist dem Dichtsitz 15 vorgelagert ein Hochdruckraum 17 ausgebildet. Das Injektorgehäuse 10 weist in einem oberen Bereich einen Aktoraufnahmeraum 18 auf, an den ein Kraftstoffzulauf 19 angeschlossen ist. Im Aktoraufnahmeraum 18 ist ein Piezo-Aktor 20 angeordnet. Der Kraftstoffzulauf 19 ist an ein Hochdrucksystem, bspw. an ein Common-Rail-System einer Dieseleinspritzeinrichtung angeschlossen. Durch die Düsennadelführung 12 führt eine Verbindungsbohrung 21, so dass der über die Kraftstoffzuführung 19 in den Aktoraufnahmeraum 18 eingeleitete Kraftstoff unter Hochdruck in den der Düsennadel 14 zugeordneten Hochdruckraum 17 geleitet wird.In the nozzle body 11, the sealing seat 15 is preceded by a high-pressure chamber 17 is formed. The injector housing 10 has an actuator receiving space 18 in an upper area, to which a fuel inlet 19 is connected. In Aktoraufnahmeraum 18 a piezoelectric actuator 20 is arranged. The fuel inlet 19 is connected to a high-pressure system, for example, to a common rail system of a diesel injection device. A connecting bore 21 passes through the nozzle needle guide 12, so that the fuel introduced via the fuel feed 19 into the actuator receiving space 18 is conducted at high pressure into the high-pressure space 17 assigned to the nozzle needle 14.

Im einem unteren Bereich des Injektorgehäuses 10 geht der Aktoraufnahmeraum 18 in einen Aufnahmeraum 22 ist für eine Druckübersetzungseinrichtung 30 über. Die Druckübersetzungseinrichtung 30 weist einen aktorseitigen Druckübersetzerkolben 31, einen düsennadelseitigen Druckübersetzerkolben 32, einen Kopplerraum 33, einen Steuerkolben 34, eine Führungshülse 35, einen inneren Rückraum 36 und einen äußeren Rückraum 37 auf. Der aktorseitige Druckübersetzerkolben 31 und der düsennadelseitige Druckübersetzerkolben 32 sind in der Führungshülse 35 geführt. Zwischen Führungshülse 35 und aktorseitigem Druckübersetzerkolben 31 ist eine Kolbenfeder 38 angeordnet, die eine an der Führungshülse 35 ausgebildete Dichtfläche 39 gegen eine an der Düsennadelführung 12 ausgebildete Stirnfläche 23 drückt. Die Kolbenfeder 38 spannt außerdem den aktorseitigen Druckübersetzerkolben 31 gegen den Piezo-Aktor 20 vor. Weiterhin greift an der Düsennadel 14 eine Schließfeder 25 an, die die Düsennadel 14 in Schließrichtung drückt.In a lower region of the injector housing 10, the actuator receiving space 18 merges into a receiving space 22 for a pressure booster 30. The pressure booster 30 has an actuator-side pressure booster piston 31, a nozzle needle side pressure booster piston 32, a coupler space 33, a control piston 34, a guide sleeve 35, an inner rear space 36 and an outer rear space 37. The actuator-side pressure booster piston 31 and the nozzle needle-side pressure booster piston 32 are guided in the guide sleeve 35. Between guide sleeve 35 and actuator-side pressure booster piston 31, a piston spring 38 is arranged, which presses a formed on the guide sleeve 35 sealing surface 39 against an opening formed on the nozzle needle guide 12 face 23. The piston spring 38 also biases the actuator-side pressure booster piston 31 against the piezo-actuator 20. Furthermore, a closing spring 25, which presses the nozzle needle 14 in the closing direction, engages on the nozzle needle 14.

Der düsennadelseitige Druckübersetzerkolben 32 ist mit einem inneren Zylinderraum 40 ausgeführt, in dem der Steuerkolben 34 axial beweglich geführt ist. Zum Kopplerraum 33 hin ist der innere Zylinderraum 40 mit einer kreisförmigen Öffnung 41 versehen, sodass sich zum Kopplerraum 33 hin eine erste, ringförmige kopplerraumseitige Druckfläche 42 am düsennadelseitigen Druckübersetzerkolben 32 ausbildet. Der Durchmesser des Zylinderraums 40 ist größer als der Durchmesser der Öffnung 41, so dass an der Öffnung 41 eine in den Zylinderraum 40 weisende ringförmige Anschlagfläche 43 für den Steuerkolben 34 entsteht. Der Zylinderraum 40 und der Steuerkolben 34 sind so ausgeführt, dass der Steuerkolben 34 im Zylinderraum 40 an der dem Kopplerraum 33 abgewandten Seite mit einer rückraumseitigen Druckfläche 48 in den inneren Rückraum 36 weist. Im inneren Rückraum 36 ist eine weitere Druckfeder 44 angeordnet, die den Steuerkolben 34 gegen die Anschlagfläche 43 drückt. In dieser Anschlagposition weist der Steuerkolben 34 eine in den Kopplerraum 40 weisende zweite, kreisförmige kopplerraumseitige Druckfläche 45 auf, die dem Querschnitt der Öffnung 41 entspricht. Der aktorseitige Druckübersetzerkolben 31 weist mit einer dritten kopplerraumseitigen Druckfläche 46 in den Kopplerraum 33.The nozzle needle-side pressure booster piston 32 is designed with an inner cylinder chamber 40 in which the control piston 34 is guided axially movable. Towards the coupler space 33, the inner cylinder space 40 is provided with a circular opening 41, so that a first, annular, coupler-space-side pressure surface 42 on the nozzle needle-side pressure booster piston 32 forms toward the coupler space 33. The diameter of the cylinder chamber 40 is greater than the diameter of the opening 41, so that at the opening 41 in the cylinder chamber 40 facing annular abutment surface 43 for the control piston 34 is formed. The cylinder chamber 40 and the control piston 34 are designed so that the control piston 34 in the cylinder chamber 40 at the side facing away from the coupler chamber 33 side with a rear-side pressure surface 48 in the inner rear space 36 has. In the inner rear space 36, a further compression spring 44 is arranged, which presses the control piston 34 against the stop surface 43. In this stop position, the control piston 34 has a second, circular, coupler space-side pressure surface 45, which points into the coupler space 40 and corresponds to the cross-section of the opening 41. The actuator-side pressure booster piston 31 has a third pressure surface 46 on the coupler-space side in the coupler space 33.

Zur Spitze der Düsennadel 14 hin ist der düsennadelseitige Übersetzerkolben 32 als Stufenkolben mit einer Ringfläche 24 ausgeführt, die innerhalb der Führungshülse 35 dem äußeren Rückraum 37 zugeordnet ist. Der äußere Rückraum 37 und der innere Rückraum 36 sind über eine hydraulisch Verbindung 47, beispielsweise eine Bohrung, verbunden.To the tip of the nozzle needle 14 toward the nozzle needle-side booster piston 32 is designed as a stepped piston with an annular surface 24 which is associated with the outer rear space 37 within the guide sleeve 35. The outer rear space 37 and the inner rear space 36 are connected via a hydraulic connection 47, for example a bore.

Im geschlossenen Zustand der Einspritzdüsen 16 ist der Dichtsitz 15 der Düsennadel 16 geschlossen. Der über die Kraftstoffzuführung 19 in den Aktoraufnahmeraum 18 und in den Druckraum 17 gelangte Systemdruck liegt in allen Druckräumen gleichermaßen an. Dabei sind Leckagespalte an der Führungshülse 35 vorhanden, so dass der Systemdruck sowohl in den Kopplerraum 33 als auch in den äußeren Rückraum 37 und über die Verbindung 47 in den inneren Rückraum 36 gelangen kann. In diesem Zustand ist die Druckübersetzungseinrichtung 30 druckausgeglichen. Außerdem ist in diesem Zustand der Aktor 20 mit einer Spannung versorgt und dadurch in seinem bestromten Zustand in seiner vertikalen Richtung gelängt. Der im Kopplerraum 33 anliegende Systemdruck wirkt in Schließrichtung auf den düsennadelseitigen Drückübersetzerkolben 32, so dass in diesem Zustand des Piezo-Aktors 20 der Dichtsitz 15 der Düsennadel 14 geschlossen ist.In the closed state of the injectors 16, the sealing seat 15 of the nozzle needle 16 is closed. The system pressure reached via the fuel supply 19 into the actuator receiving space 18 and into the pressure chamber 17 is equal in all pressure chambers. In this case, there are leakage gaps on the guide sleeve 35, so that the system pressure can reach both into the coupler space 33 and into the outer rear space 37 and via the connection 47 into the inner rear space 36. In this state, the pressure booster 30 is pressure balanced. In addition, in this state, the actuator 20 is supplied with a voltage and thereby elongated in its energized state in its vertical direction. The system pressure applied in the coupler chamber 33 acts in the closing direction on the nozzle needle-side pressure-translating piston 32, so that in this state of the piezo-actuator 20, the sealing seat 15 of the nozzle needle 14 is closed.

Wird die Spannung am Piezo-Aktor 20 reduziert bzw. der Piezo-Aktor 20 stromlos geschaltet, wird ebenso die Länge des Piezo-Aktors 20 in vertikaler Richtung reduziert. Durch den mittels der Kolbenfeder 38 in Richtung des Piezo-Aktors 20 vorgespannten aktorseitigen Druckübersetzerkolbens 31 wird dieser aufgrund der reduzierten vertikalen Länge des Piezo-Aktors 20 ebenfalls in vertikaler Richtung bewegt. Durch diese nach au-ßen gerichtete ziehende Bewegung des aktorseitigen Druckübersetzerkolbens 31 in der Führungshülse 35 vergrößert sich das Volumen im Kopplerraum 33, wodurch dort eine Druckreduzierung stattfindet, die einen Öffnungsdruck pö1 für einer erste Stufe zum Öffnen der Düsennadel 14 liefert. Die Druckübersetzung für die erste Öffnungsstufe wird durch das Verhältnis der aktorseitigen Druckübersetzerkolben 31 ausgebildteten dritten kopplerraumseitigen Druckfläche 46 zur gemeinsamen kopplerraumseitigen Druckfläche gebildet, wobei die gemeinsame kopplerraumseitige Druckfläche sich aus der ersten, ringförmigen kopplerraumseitigen Druckfläche 42 des düsennadelseitigen Druckübersetzerkolbens 32 und der zweiten, kreisförmigen kopplerraumseitigen Druckfläche 45 des Steuerkolbens 34 zusammensetzt. Durch den Hub des düsennadelseitigen Druckübersetzerkolbens 32 innerhalb des Führungshülse 35 wird gleichzeitig der Druck im äußeren Rückraum 37 reduziert. Diese Druckreduzierung wird über die Verbindung 47 auf den inneren Rückraum 36 übertragen, so dass die auf den Steuerkolben 34 wirkende Federkraft der Druckfeder 44 überwunden wird und dadurch sich der Steuerkolben 34 von der Anschlagfläche 43 löst. In dieser von der Anschlagfläche 43 abgehobenen Position des Steuerkolbens 34 steht der düsennadelseitige Druckübersetzerkolben 32 nur noch mit der ersten, ringförmigen kopplerraumseitigen Druckfläche 42, die von der stirnseitigen Ringfläche gebildet wird, als wirksame Druckfläche mit dem Kopplerraum 33 in Verbindung. Aufgrund der reduzierten wirksamen Druckfläche am düsennadelseitigen Druckübersetzerkolben 32 wird eine zweite Druckübersetzungsstufe eingeleitet, die im Vergleich zum Hub des Piezo-Aktors 20 bzw. des aktorseitigen Druckübersetzerkolbens 32 einen zusätzlichen Hub realisiert.If the voltage at the piezoelectric actuator 20 is reduced or the piezoelectric actuator 20 is de-energized, the length of the piezoelectric actuator 20 in the vertical direction is likewise reduced. Due to the biased by the piston spring 38 in the direction of the piezo-actuator 20 actuator-side pressure booster piston 31 this is also moved in the vertical direction due to the reduced vertical length of the piezo-actuator 20. As a result of this outwardly directed pulling movement of the actuator-side pressure booster piston 31 in the guide sleeve 35, the volume in the coupler space 33 increases, whereby there takes place a pressure reduction which delivers an opening pressure p ö1 for a first stage for opening the nozzle needle 14. The pressure ratio for the first opening stage is formed by the ratio of the actuator-side pressure booster piston 31 formed third kopplerraumseitigen pressure surface 46 to the common kopplerraumseitigen pressure surface, wherein the common kopplerraumseitige pressure surface is composed of the first annular kopplerraumseitigen pressure surface 42 of the nozzle needle side pressure booster piston 32 and the second, circular kopplerraumseitigen pressure surface 45 of the control piston 34. By the stroke of the nozzle needle-side pressure booster piston 32 within the guide sleeve 35, the pressure in the outer rear space 37 is simultaneously reduced. This pressure reduction is transmitted via the connection 47 to the inner rear space 36, so that the force acting on the control piston 34 spring force of the compression spring 44 is overcome and thereby releases the control piston 34 from the stop surface 43. In this lifted off from the stop surface 43 position of the control piston 34 of the nozzle needle side pressure booster piston 32 is only with the first, annular kopplerraumseitigen pressure surface 42, which is formed by the frontal annular surface, as effective pressure surface with the coupler chamber 33 in connection. Due to the reduced effective pressure surface on the nozzle needle side pressure booster piston 32, a second pressure booster stage is introduced, which realizes an additional stroke compared to the stroke of the piezo actuator 20 and the actuator-side pressure booster piston 32.

Durch Bestromen des Piezo-Aktors 20 wird wieder eine Verlängerung des Piezo-Aktors 20 eingeleitet, die vom aktorseitigen Druckübersetzerkolben 31 übertragen einen Druckanstieg im Kopplerraum 33 erzeugt, der zum Schließen der Düsennadel 14 führt. Die auf die Düsennadel 14 wirkende Schließfeder 25 hält die hält die Einspritzdüsen 16 im betriebslosen Zustand geschlossen.By energizing the piezo-actuator 20, an extension of the piezo-actuator 20 is again introduced, which is transmitted from the actuator-side pressure booster piston 31 generates a pressure increase in the coupler chamber 33, which leads to the closing of the nozzle needle 14. The acting on the nozzle needle 14 closing spring 25 holds the holds the injectors 16 closed in the idle state.

BezugszeichenlisteLIST OF REFERENCE NUMBERS

1010
Injektorgehäuseinjector
1111
Düsenkörpernozzle body
1212
DüsennadelführungNozzle needle guide
1313
Führungsbohrungguide bore
1414
Düsennadelnozzle needle
1515
Dichtsitzsealing seat
1616
Einspritzdüseninjectors
1717
HochdruckraumHigh-pressure chamber
1818
AktoraufnahmeraumAktoraufnahmeraum
1919
KraftstoffzulaufFuel supply
2020
Piezo-AktorPiezo actuator
2121
Verbindungsbohrungconnecting bore
2222
Aufnahmeraumaccommodation space
2323
Stirnflächeface
2424
Ringflächering surface
2525
Schließfederclosing spring
3030
DruckübersetzungseinrichtungPressure booster device
3131
aktorseitiger DruckübersetzerkolbenActuator-side pressure booster piston
3232
düsennadelseitiger DruckübersetzerkolbenNozzle needle side pressure booster piston
3333
Kopplerraumcoupler
3434
Steuerkolbenspool
3535
Führungshülseguide sleeve
3636
inneren Rückrauminner back space
3737
äußeren Rückraumouter rear space
38 838 8
Kolbenfederpiston spring
3939
Dichtflächesealing surface
4040
Zylinderraumcylinder space
41 141 1
Öffnungopening
4242
erste, ringförmige kopplerraumseitige Druckflächefirst, annular, coupler-chamber-side pressure surface
4343
Anschlagflächestop surface
4444
Druckfedercompression spring
4545
zweite, kreisförmige kopplerraumseitige Druckflächesecond, circular, coupler space-side pressure surface
4646
dritte kopplerraumseitige Druckflächethird coupler chamber-side pressure surface
4747
Verbindungconnection
4848
rückraumseitige Druckflächerear space side pressure surface

Claims (8)

  1. Fuel injector for an internal combustion engine having a nozzle needle (14) which is guided in a nozzle body (11) and which acts on a nozzle needle sealing seat (15), having an actuator (20) and having a hydraulic pressure boosting device (30) with an actuator-side pressure booster piston (31) which is connected to the actuator (20) and with a nozzle-needle-side pressure booster piston (32) which is connected to the nozzle needle (14), which actuator-side pressure booster piston (31) and nozzle-needle-side pressure booster piston (32) act in each case on a coupler space (33), and with the nozzle needle (14) being lifted up from the nozzle needle sealing seat (15) as a function of the pressure in the coupler space (33) and with highly pressurized fuel thereby being injected from a high-pressure space (17) into a combustion chamber of the internal combustion engine, characterized in that a cylinder space (40) is formed on the nozzle-needle-side pressure booster piston (32), in which cylinder space (40) is axially guided a control piston (34), a coupler-space-side pressure surface (45) of which control piston (34) is exposed to the coupler space (33) and a rear-space-side pressure surface (48) of which control piston (34) is exposed to an inner rear space (36) formed in the cylinder space (40), and in that an outer rear space (37) is assigned to the nozzle-needle-side pressure booster piston (32), which outer rear space (37) is connected by means of a hydraulic connection (47) to the inner rear space (36) which acts on the control piston (34) .
  2. Fuel injector according to Claim 1, characterized in that the outer rear space (37) is assigned, at the side opposite the coupler space (33), to the nozzle-needle-side pressure booster piston (32).
  3. Fuel injector according to Claim 1 or 2, characterized in that the nozzle-needle-side pressure booster piston (32) forms a common coupler-space-side pressure surface, which points into the coupler space (33), with the control piston (34) when the control piston (34) is in a stop position, which coupler-space-side pressure surface forms a first pressure boost ratio for a first boost stage with a third coupler-space-side pressure surface (46) which is formed by the actuator-side pressure booster piston (31) and which points into the coupler space (25).
  4. Fuel injector according to Claim 3, characterized in that a stop surface (43) is formed in the cylinder space (40) to form the stop position of the control piston (34).
  5. Fuel injector according to Claim 4, characterized in that the control piston (34) is pre-loaded against the stop surface (43) by means of a pressure spring (44).
  6. Fuel injector according to Claim 4 or 5, characterized in that, when the control piston (34) is in a position in which it is lifted up from the stop surface (43), the first annular coupler-space-side pressure surface (42), which points from the nozzle-needle-side pressure booster piston (32) into the coupler space (33), forms a second pressure boost ratio with the third coupler-space-side pressure surface (46) which is formed by the actuator-side pressure booster piston (31) and which points into the coupler space (33), which second pressure boost ratio realizes an opening stroke, which goes beyond the stroke of the actuator (20), for a second boost stage.
  7. Fuel injector according to Claim 1, characterized in that the actuator-side pressure booster piston (31) and the nozzle-needle-side pressure booster piston (32) are guided in a guide sleeve (35).
  8. Fuel injector according to Claim 7, characterized in that the actuator-side pressure booster piston (31) is pre-loaded counter to the closing direction of the nozzle needle (14) by means of a piston spring (38), and in that the piston spring (38) is supported on the guide sleeve (35).
EP05112500A 2005-02-02 2005-12-20 Fuel injector with direct needle control for an internal combustion engine Ceased EP1688611B1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE102005004738A DE102005004738A1 (en) 2005-02-02 2005-02-02 Fuel injector with direct needle control for an internal combustion engine

Publications (3)

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EP1688611A2 EP1688611A2 (en) 2006-08-09
EP1688611A3 EP1688611A3 (en) 2007-01-10
EP1688611B1 true EP1688611B1 (en) 2008-07-30

Family

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EP05112500A Ceased EP1688611B1 (en) 2005-02-02 2005-12-20 Fuel injector with direct needle control for an internal combustion engine

Country Status (4)

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US (1) US7419103B2 (en)
EP (1) EP1688611B1 (en)
AT (1) ATE403082T1 (en)
DE (2) DE102005004738A1 (en)

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US9309846B2 (en) 2012-11-12 2016-04-12 Mcalister Technologies, Llc Motion modifiers for fuel injection systems
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Also Published As

Publication number Publication date
DE502005004874D1 (en) 2008-09-11
EP1688611A3 (en) 2007-01-10
US20060169802A1 (en) 2006-08-03
ATE403082T1 (en) 2008-08-15
US7419103B2 (en) 2008-09-02
DE102005004738A1 (en) 2006-08-10
EP1688611A2 (en) 2006-08-09

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