EP1789675B1 - Method and device for characterising a return stroke of injectors - Google Patents

Method and device for characterising a return stroke of injectors Download PDF

Info

Publication number
EP1789675B1
EP1789675B1 EP05777858A EP05777858A EP1789675B1 EP 1789675 B1 EP1789675 B1 EP 1789675B1 EP 05777858 A EP05777858 A EP 05777858A EP 05777858 A EP05777858 A EP 05777858A EP 1789675 B1 EP1789675 B1 EP 1789675B1
Authority
EP
European Patent Office
Prior art keywords
rail pressure
energy
actuator
rail
injectors
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.)
Expired - Fee Related
Application number
EP05777858A
Other languages
German (de)
French (fr)
Other versions
EP1789675A1 (en
Inventor
Uwe Jung
Janos Radeczky
Michael Wirkowski
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.)
Continental Automotive GmbH
Original Assignee
Continental Automotive GmbH
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 Continental Automotive GmbH filed Critical Continental Automotive GmbH
Publication of EP1789675A1 publication Critical patent/EP1789675A1/en
Application granted granted Critical
Publication of EP1789675B1 publication Critical patent/EP1789675B1/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/20—Output circuits, e.g. for controlling currents in command coils
    • F02D41/2096—Output circuits, e.g. for controlling currents in command coils for controlling piezoelectric injectors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/04—Introducing corrections for particular operating conditions
    • F02D41/042—Introducing corrections for particular operating conditions for stopping the engine
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
    • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
    • F02D41/2425—Particular ways of programming the data
    • F02D41/2429—Methods of calibrating or learning
    • F02D41/2438—Active learning methods
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
    • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
    • F02D41/2425—Particular ways of programming the data
    • F02D41/2429—Methods of calibrating or learning
    • F02D41/2451—Methods of calibrating or learning characterised by what is learned or calibrated
    • F02D41/2464—Characteristics of actuators
    • F02D41/2467—Characteristics of actuators for injectors
    • F02D41/247—Behaviour for small quantities
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/30—Controlling fuel injection
    • F02D41/38—Controlling fuel injection of the high pressure type
    • F02D41/3809—Common rail control systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2200/00—Input parameters for engine control
    • F02D2200/02—Input parameters for engine control the parameters being related to the engine
    • F02D2200/06—Fuel or fuel supply system parameters
    • F02D2200/0602—Fuel pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M65/00—Testing fuel-injection apparatus, e.g. testing injection timing ; Cleaning of fuel-injection apparatus
    • F02M65/005—Measuring or detecting injection-valve lift, e.g. to determine injection timing

Definitions

  • the invention relates to a method for Leerhuberkennung injectors according to the independent claim 1 and relates to a device for Leerhuberkennung injectors according to the independent claim.
  • Such methods such as from the EP-A-1 236 880 are known to be crucial to ensure the accuracy of the dosage for small injection quantities. If the small injection quantities are inaccurate, then the strict emission standards for diesel passenger car engines can not be met.
  • methods are known which compensate the injector for injector scattering during engine operation. For example, can be determined via a knock sensor of the internal combustion engine, which control parameters are necessary to control the individual injector so that just fuel is injected (switching leakage).
  • the activation condition of the method depends on the driving behavior of the driver. To determine the idle stroke with such a method, it is necessary that the operating condition of the internal combustion engine remains unchanged for a certain period of time. If this corresponding period is interrupted by the driving behavior of the driver, then the Leerhubbeées can not be completed.
  • the invention has for its object to provide a method and apparatus for Leerhuberkennung of injectors, which are independent of the driving behavior of the driver.
  • the invention is characterized by a method and device for Leerhuberkennung injectors.
  • a constant pressure, a steady pressure drop or build-up is set.
  • the current rail pressure is measured.
  • An actuator of the injector is driven by an actuator energy.
  • the set actuator energy is then changed. This is repeated until a discontinuity has occurred in the course of the rail pressure.
  • the actuator energy is increased continuously or stepwise.
  • the change of the actuator energy is limited by the possibility of the power level. For cost reasons, a gradual change is preferable.
  • the rail pressure reduction can be adjusted when switching off the internal combustion engine. After switching off the engine no fuel is pumped into the fuel tank more. Due to leaks, the pressure in the fuel tank automatically drops. Eventually, additional leakage through one of the injectors is desired.
  • a further embodiment of the invention is to set a steady pressure build-up when starting the internal combustion engine.
  • the feed pump promotes fuel in the fuel tank (rail) and thus builds slowly and steadily on the pressure in it.
  • This can also be used to determine the value pairs pressure and associated injector energy (actuator energy).
  • such value pairs are stored, for example, in a memory.
  • a further embodiment of the invention after determining a discontinuity in the time course of the rail pressure to set the actuator energy to an initial value, wherein then the current rail pressure is measured, the actuator of the injector is driven with an actuator energy and the actuator energy is changed until a discontinuity occurs again in the time course of the rail pressure.
  • the actuator of the injector is driven with an actuator energy and the actuator energy is changed until a discontinuity occurs again in the time course of the rail pressure.
  • FIG. 1 shows in the upper section of the diagram the time profile with 1 rail pressure marked. In the lower part of the diagram, the time profile is shown with 2 labeled actuator energy.
  • a fuel reservoir is present, to which an injector, in particular a piezo injector, is connected.
  • the actuator of the injector, here piezo actuator receives a drive signal with the energy shown in the figure 1.
  • the pressure in the common rail system builds up linearly and steadily until time t 1 .
  • the pressure reduction in the fuel storage of the common rail system is due to leakage currents.
  • a drive signal with the energy E 1 is then applied to the piezoelectric actuator of the injector at time t 2 .
  • the energy E 1 is too low to push the servo valve of the injector out of its seat.
  • the actuator energy is raised to E 2 .
  • the drive signal is applied to the piezoelectric actuator. As can be seen in the pressure curve 1 shown above, this energy E 2 is too low.
  • Known systems that evaluate the combustion signal can supplement the inventive method or device and can detect the ratio between idle stroke and injector seat wear with respect to quantity correction of the individual injectors separately.
  • the method according to the invention makes it possible to expand the very narrow injector production tolerances and reduces the scrap content of the injectors produced.
  • piezo actuators need not be preconditioned, since the method according to the invention compensates for the idle stroke directly over the service life by adapting the energy.
  • the method or device according to the invention is distinguished by its robustness compared with the other known methods, and since the method according to the invention can be implemented without additional components.

Abstract

The invention relates to a method and device for characterising the return stroke of injectors, in particular piezo-injectors of an internal combustion engine provided with a common rail system. When the internal combustion engine is switched off, a constant pressure is dropped in the rail, thereby making it possible to measure the rail pressure and to adjust the injectors by corresponding power. The actuating power is increased until a discontinuity in a temporal progression of rail pressure occurs. The actuating energy applied for said state and a pressure available in the make it possible to measure the return stroke of corresponding injector.

Description

Die Erfindung betrifft ein Verfahren zur Leerhuberkennung von Injektoren gemäß dem unabhängigen Anspruch 1 und betrifft eine Vorrichtung zur Leerhuberkennung von Injektoren gemäß dem unabhängigen Anspruch 9.The invention relates to a method for Leerhuberkennung injectors according to the independent claim 1 and relates to a device for Leerhuberkennung injectors according to the independent claim. 9

Solche Verfahren, wie z.B. aus der EP-A-1 236 880 bekannt, sind von entscheidender Bedeutung, um die Genauigkeit der Dosierung bei kleinen Einspritzmengen zu gewährleisten. Sind die kleinen Einspritzmengen ungenau, so können die strengen Abgasnormen bei Diesel Pkw-Motoren nicht eingehalten werden. Es gibt zwei grundlegende Entwicklungen, um die Injektor zur Injektorstreuung zu minimieren. Dies kann einerseits durch eine hochpräzise und sehr teure Injektorfertigung bewerkstelligt werden. Dabei werden alle Injektoren in der Fertigungsstraße vermessen und die außerhalb der engen Toleranz liegenden Injektoren aussortiert. Andererseits sind Verfahren bekannt, die während des Motorbetriebes die Injektor zur Injektorstreuung ausgleichen. Beispielsweise kann über einen Klopfsensor der Brennkraftmaschine festgestellt werden, welche Ansteuerparameter notwendig sind, um den einzelnen Injektor anzusteuern, so dass gerade Kraftstoff eingespritzt wird (Schaltleckage). Dabei ist es nachteilig, dass die Aktivierungsbedingung des Verfahrens vom Fahrverhalten des Fahrers abhängt. Zur Feststellung des Leerhubes mit einem solchen Verfahren, ist es notwendig, dass die Betriebsbedingung der Brennkraftmaschine für einen gewissen Zeitraum unverändert bleibt. Wird dieser entsprechende Zeitraum durch das Fahrverhalten des Fahrers unterbrochen, so kann die Leerhubbestimmung nicht vollständig abgeschlossen werden.Such methods, such as from the EP-A-1 236 880 are known to be crucial to ensure the accuracy of the dosage for small injection quantities. If the small injection quantities are inaccurate, then the strict emission standards for diesel passenger car engines can not be met. There are two basic developments to minimize the injector for injector scattering. On the one hand, this can be accomplished by a high-precision and very expensive injector production. All injectors in the production line are measured and the out-of-tolerance injectors sorted out. On the other hand, methods are known which compensate the injector for injector scattering during engine operation. For example, can be determined via a knock sensor of the internal combustion engine, which control parameters are necessary to control the individual injector so that just fuel is injected (switching leakage). It is disadvantageous that the activation condition of the method depends on the driving behavior of the driver. To determine the idle stroke with such a method, it is necessary that the operating condition of the internal combustion engine remains unchanged for a certain period of time. If this corresponding period is interrupted by the driving behavior of the driver, then the Leerhubbestimmung can not be completed.

Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren und eine Vorrichtung zur Leerhuberkennung von Injektoren vorzustellen, die unabhängig vom Fahrverhalten des Fahrers sind.The invention has for its object to provide a method and apparatus for Leerhuberkennung of injectors, which are independent of the driving behavior of the driver.

Die Aufgabe der Erfindung wird durch die Merkmale des unabhängigen Anspruchs 1 und durch die Merkmale des unabhängigen Anspruchs 9 gelöst.The object of the invention is solved by the features of independent claim 1 and by the features of independent claim 9.

Die Erfindung zeichnet sich durch ein Verfahren bzw. Vorrichtung zur Leerhuberkennung von Injektoren aus. Dabei wird ein konstanter Druck, ein stetiger Druckabfall oder -aufbau eingestellt. Der aktuelle Raildruck wird gemessen. Ein Aktuator des Injektors wird mit einer Aktuatorenergie angesteuert. Die eingestellte Aktuatorenergie wird anschließend verändert. Dies wird wiederholt, bis im zeitlichen Verlauf des Raildrucks eine Unstetigkeit aufgetreten ist. Vorzugsweise wird die Aktuatorenergie kontinuierlich oder schrittweise erhöht. Die Änderung der Aktuatorenergie ist durch die Möglichkeit der Leistungsstufe begrenzt. Aus Kostengründen ist eine schrittweise Änderung vorzuziehen. Vorzugsweise kann der Raildruckabbau beim Abstellen der Brennkraftmaschine eingestellt werden. Nach Abstellen der Brennkraftmaschine wird kein Kraftstoff in den Kraftstoffspeicher mehr gefördert. Aufgrund von Leckagen fällt der im Kraftstoffspeicher vorhandene Druck automatisch ab. Eventuelle ist eine zusätzliche Leckage durch eines der Injektoren erwünscht.The invention is characterized by a method and device for Leerhuberkennung injectors. In this case, a constant pressure, a steady pressure drop or build-up is set. The current rail pressure is measured. An actuator of the injector is driven by an actuator energy. The set actuator energy is then changed. This is repeated until a discontinuity has occurred in the course of the rail pressure. Preferably, the actuator energy is increased continuously or stepwise. The change of the actuator energy is limited by the possibility of the power level. For cost reasons, a gradual change is preferable. Preferably, the rail pressure reduction can be adjusted when switching off the internal combustion engine. After switching off the engine no fuel is pumped into the fuel tank more. Due to leaks, the pressure in the fuel tank automatically drops. Eventually, additional leakage through one of the injectors is desired.

Eine weitere Ausgestaltung der Erfindung ist es, einen stetigen Druckaufbau beim Starten der Brennkraftmaschine einzustellen. Beim Starten der Brennkraftmaschine fördert die Förderpumpe Kraftstoff in den Kraftstoffspeicher (Rail) und baut somit langsam und stetig den Druck darin auf. Dies kann ebenfalls dazu verwendet werden, um die Wertepaare Druck und dazugehörige Injektorenergie (Aktorenergie) zu ermitteln. Vorzugsweise werden solche Wertepaare beispielsweise in einem Speicher abgelegt.A further embodiment of the invention is to set a steady pressure build-up when starting the internal combustion engine. When starting the internal combustion engine, the feed pump promotes fuel in the fuel tank (rail) and thus builds slowly and steadily on the pressure in it. This can also be used to determine the value pairs pressure and associated injector energy (actuator energy). Preferably, such value pairs are stored, for example, in a memory.

Eine weitere Ausgestaltung der Erfindung, ist es, nach Ermittlung einer Unstetigkeit im zeitlichen Verlauf des Raildrucks die Aktuatorenergie auf einen Anfangswert zu setzen, wobei anschließend der aktuelle Raildruck gemessen wird, der Aktuator des Injektors angesteuert wird mit einer Aktuatorenergie und die Aktuatorenergie solange verändert wird, bis erneut im zeitlichen Verlauf des Raildrucks eine Unstetigkeit auftritt. Bei hochdichten Common-Rail-Systemen, bei denen der Druckabfall von Haus aus sehr gering ist, ist es möglich, bei einem einzigen Abstellvorgang der Brennkraftmaschine die Energie der Schaltleckagen bei unterschiedlichen Raildrücken zu erfassen. Die Energie für die Schaltleckage ist vom Raildruck abhängig. Bei hohen Raildrücken ist eine höhere Energie als bei niedrigen Raildrücken nötig. Damit sind weniger Abschaltvorgänge nötig, um die Wertepaare Aktuatorenergie und Raildrücke zu aktualisieren.A further embodiment of the invention, after determining a discontinuity in the time course of the rail pressure to set the actuator energy to an initial value, wherein then the current rail pressure is measured, the actuator of the injector is driven with an actuator energy and the actuator energy is changed until a discontinuity occurs again in the time course of the rail pressure. In high-density common rail systems, where the pressure drop is very low from the house, it is possible to detect the energy of the switching leaks at different Raildrücken in a single shutdown of the engine. The energy for the switching leakage depends on the rail pressure. At high rail pressures, a higher energy is required than at low rail pressures. This means fewer shutdown processes are required to update the value pairs of actuator energy and rail pressures.

Weitere vorteilhafte Ausgestaltungen der Erfindung sind in den abhängigen Ansprüchen wiedergegeben.Further advantageous embodiments of the invention are given in the dependent claims.

Die Erfindung wird nachfolgend unter Bezugnahme auf die schematische Zeichnung beispielhaft erläutert. Dabei zeigt:

Figur 1
einen zeitlichen Verlauf eines Raildrucks und einen zeitlichen Verlauf einer Aktorenergie.
The invention will now be described by way of example with reference to the schematic drawing. Showing:
FIG. 1
a time course of a rail pressure and a time course of an actuator energy.

Beispielhaft wird das erfindungsgemäße Verfahren anhand des Abschaltvorgangs der Brennkraftmaschine näher erläutert.By way of example, the method according to the invention will be explained in more detail with reference to the shutdown process of the internal combustion engine.

Die Figur 1 zeigt im oberen Abschnitt des Diagramms den zeitlichen Verlauf mit 1 gekennzeichnetem Raildrucks. Im unteren Bereich des Diagramms ist der zeitliche Verlauf mit 2 gekennzeichneten Aktuatorenergie abgebildet.FIG. 1 shows in the upper section of the diagram the time profile with 1 rail pressure marked. In the lower part of the diagram, the time profile is shown with 2 labeled actuator energy.

In einem Common-Rail-System ist ein Kraftstoffspeicher vorhanden, an dem ein Injektor, insbesondere ein Piezoinjektor, angeschlossen ist. Der Aktuator des Injektors, hier Piezoaktuator erhält ein Ansteuersignal mit der in der Figur 1 dargestellten Energie.In a common-rail system, a fuel reservoir is present, to which an injector, in particular a piezo injector, is connected. The actuator of the injector, here piezo actuator receives a drive signal with the energy shown in the figure 1.

Beim Abschalten einer Brennkraftmaschine mit einem Common-Rail-System baut sich der Druck im Common-Rail-System bis zum Zeitpunkt t1 linear und stetig ab. Der Druckabbau im Kraftstoffspeicher des Common-Rail-Systems ist durch Leckageströme bedingt. Erfindungsgemäß wird nun ein Ansteuerungssignal mit der Energie E1 zum Zeitpunkt t2 an den Piezoaktor des Injektors angelegt. Die Energie E1 ist zu gering um den Servoventil des Injektors aus dessen Sitz zu drücken. Zum Zeitpunkt t3 wird die Aktorenergie auf E2 angehoben. Mit einer kurzen Verzögerung zum Zeitpunkt t4 wird das Ansteuerungssignal an den Piezoaktor angelegt. Wie im oben abgebildeten Druckverlauf 1 zu erkennen ist, ist auch diese Energie E2 zu gering. Dieser Vorgang wird wiederholt, bis die Aktorenergie die minimale Energie Emin (p1) erreicht hat. Mit dieser Energie Emin (p1) wird zum Zeitpunkt t1 ein Ansteuersignal an den Piezoaktor angelegt. Dieses Mal ist die Energie ausreichend, um das Servoventil aus seinem Sitz zu drücken, was zur Folge hat, dass der Raildruck schlagartig sinkt. Dies ist in Figur 1 als Flanke 2 zu erkennen. Diese Flanke 2 bzw. Unstetigkeit im zeitlichen Verlauf des Raildrucks kann genutzt werden, um die minimale Aktuatorenergie dem entsprechenden Raildruck p1 zuzuordnen. Ist im Rail noch ausreichend Druck vorhanden, so kann das erfindungsgemäße Verfahren erneut wiederholt werden. Dabei wird die Aktuatorenergie auf den Anfangswert E3 gesetzt. Zum Zeitpunkt t5 wird ein Ansteuersignal mit der Energie E3 an den Piezoaktor angelegt. Da die Energie E3 zu gering ist, um das Servoventil aus dem Sitz zu drücken, wird die Energie erneut angehoben und entsprechend ein Ansteuersignal auf den Aktor abgegeben. Dies wird solange wiederholt, bis ausreichend Energie vorhanden ist, um das Servoventil aus dem Sitz zu drücken. Dies erfolgt dieses Mal bei einer Energie Emin (2). Mit dieser Energie wird der Piezoaktor mit einem Ansteuerungssignal zum Zeitpunkt t6 beaufschlagt. Dies bewirkt erneut einen drastischen Druckabfall im Rail. Der Raildruck fällt von p2 auf p3. Damit ist ein weiteres Wertepaar (Energie, Druck) ermittelt worden. Mit der Zeit werden alle Wertepaare aktualisiert.When switching off an internal combustion engine with a common rail system, the pressure in the common rail system builds up linearly and steadily until time t 1 . The pressure reduction in the fuel storage of the common rail system is due to leakage currents. According to the invention, a drive signal with the energy E 1 is then applied to the piezoelectric actuator of the injector at time t 2 . The energy E 1 is too low to push the servo valve of the injector out of its seat. At time t 3 , the actuator energy is raised to E 2 . With a short delay at time t 4 , the drive signal is applied to the piezoelectric actuator. As can be seen in the pressure curve 1 shown above, this energy E 2 is too low. This process is repeated until the actuator energy has reached the minimum energy E min (p 1 ). With this energy E min (p 1 ), a drive signal is applied to the piezoelectric actuator at time t1. This time, the energy is sufficient to push the servo valve out of its seat, causing the rail pressure to suddenly drop. This can be seen in Figure 1 as edge 2. This edge 2 or discontinuity in the time course of the rail pressure can be used to assign the minimum actuator energy to the corresponding rail pressure p 1 . If sufficient pressure is still present in the rail, the method according to the invention can be repeated again. The actuator energy is set to the initial value E 3 . At time t 5 , a drive signal with the energy E 3 is applied to the piezoelectric actuator. Since the energy E 3 is too low to push the servo valve from the seat, the energy is raised again and delivered according to a drive signal to the actuator. This is repeated until sufficient energy is available to force the servo valve out of the seat. This is done this time at an energy E min (2) . With this energy, the piezoelectric actuator with a drive signal at time t 6 is applied. This again causes a drastic pressure drop in the rail. The rail pressure drops from p 2 to p 3 . This is another value pair (energy, pressure) has been determined. Over time, all value pairs will be updated.

Alternativ dazu ist es denkbar, während einer Schubphase einer Brennkraftmaschine dieses erfindungsgemäße Verfahren durchzuführen. Dies eröffnet die Möglichkeit den Raildruck auf einen gewünschten Adaptionswert zu bringen, beispielsweise durch Öffnen eines Volumenstromregelventils (VCV). Da die Brennkraftmaschine im Schubbetrieb noch am Laufen ist, kann die Förderpumpe demzufolge Kraftstoff in den Rail nachliefern, um den Druck dort entsprechend auf den gewünschten Adaptionswert zu erhöhen. Nach erfolgter Adaption eines Injektors - nach Eintreten eines unstetigen Druckabfalls - kann der nächste Injektor adaptiert werden, wobei der gleiche Ausgangsdruck wie am ersten Injektor eingestellt wird. Dies wird wiederholt bis alle Injektoren der Brennkraftmaschine adaptiert wurden. Damit können gezielt alle Injektoren für bestimmte Druckwerte adaptiert werden.Alternatively, it is conceivable to carry out this method according to the invention during a coasting phase of an internal combustion engine. This opens up the possibility of bringing the rail pressure to a desired adaptation value, for example by opening a volume flow control valve (VCV). Since the internal combustion engine is still running in overrun mode, the delivery pump can consequently supply fuel to the rail in order to increase the pressure there to the desired adaptation value. After the adaptation of an injector - after a discontinuous pressure drop occurs - the next injector can be adapted, with the same output pressure is set as the first injector. This is repeated until all injectors of the internal combustion engine have been adapted. This means that all injectors can be specifically adapted for specific pressure values.

Mit diesem erfindungsgemäßen Verfahren ist sichergestellt, dass eine Leerhubkorrektur der Injektoren unabhängig vom Fahrprofil eines Fahrers erfolgt, da bei jedem Motorabstellen das erfindungsgemäße Verfahren durchgeführt werden kann. Das erfindungsgemäße Verfahren ermöglicht eine genaue Energievorsteuerung zu erlernen, selbst bei bekannten Systemen zum Ausregeln von Leerhubunterschieden zwischen den einzelnen Injektoren durch Energieanpassung. Solche Systeme benötigen eine minimale Ansteuerzeit und das Erreichen einer bestimmten Aktivierungsbedingung zum Ausführen des bekannten Systems.With this method according to the invention, it is ensured that an idle stroke correction of the injectors takes place independently of the driving profile of a driver, since the method according to the invention can be carried out with each engine shutdown. The method according to the invention makes it possible to learn precise energy precontrol, even in the case of known systems for regulating idle stroke differences between the individual injectors by energy adaptation. Such systems require a minimum drive time and the achievement of a certain activation condition for carrying out the known system.

Bekannte Systeme, die das Verbrennungssignal auswerten, wie Klopfsensor oder Drehzahlsensor, können das erfindungsgemäße Verfahren bzw. Vorrichtung ergänzen und können das Verhältnis zwischen Leerhub und Injektorsitzverschleiß bezüglich Mengenkorrektur der einzelnen Injektoren separat erfassen. Durch Kombination des erfindungsgemäßen Verfahrens und von bekannten Systemen werden größere Datenmengen erfasst und erlauben dadurch eine genauere Berechnung der Ansteuerzeitkorrektur.Known systems that evaluate the combustion signal, such as knock sensor or speed sensor, can supplement the inventive method or device and can detect the ratio between idle stroke and injector seat wear with respect to quantity correction of the individual injectors separately. By combining the method according to the invention and of known systems, larger amounts of data are acquired and thereby allow a more accurate calculation of the actuation time correction.

Grundsätzlich ermöglicht das erfindungsgemäße Verfahren das Aufweiten der sehr engen Injektorfertigungstoleranzen und reduziert den Ausschussanteil der hergestellten Injektoren. Darüber hinaus müssen Piezoaktoren nicht vorkonditionierter werden, da das erfindungsgemäße Verfahren durch Energieanpassung den Leerhub direkt über die Lebensdauer kompensiert. Außerdem zeichnet sich das erfindungsgemäße Verfahren bzw. Vorrichtung gegenüber den anderen bekannten Verfahren durch ihre Robustheit aus und da das erfindungsgemäße Verfahren ohne zusätzliche Bauteile realisierbar ist.In principle, the method according to the invention makes it possible to expand the very narrow injector production tolerances and reduces the scrap content of the injectors produced. In addition, piezo actuators need not be preconditioned, since the method according to the invention compensates for the idle stroke directly over the service life by adapting the energy. In addition, the method or device according to the invention is distinguished by its robustness compared with the other known methods, and since the method according to the invention can be implemented without additional components.

Claims (11)

  1. Method for detecting the idle stroke of injectors, in particular piezo injectors, of an internal combustion engine having a common rail system comprises the following steps:
    a) setting a constant rail pressure, a continuous rail pressure drop or build-up,
    b) measuring the current rail pressure,
    c) activating at least one injector actuator by means of an amount of actuator energy,
    d) changing the actuator energy,
    e) repeating the steps b) to d) until a discontinuity occurs in the variation of the rail pressure over time.
  2. Method according to claim 1, characterised in that the actuator energy is changed discretely to another actuator energy level, with the actuator of the injector being activated by means of at least one activation signal per set actuator energy level.
  3. Method according to one of the preceding claims, characterised in that the applied actuator energy is constant over time and is increased or reduced when it changes by a specific amount of energy.
  4. Method according to one of the preceding claims, characterised in that the applied actuator energy is increased continuously or decreased continuously.
  5. Method according to one of the preceding claims, characterised in that a continuous drop in rail pressure is set in step a) when the internal combustion engine is switched off.
  6. Method according to one of the preceding claims, characterised in that a continuous build-up in rail pressure is set in step a) when the internal combustion engine is started.
  7. Method according to one of the preceding claims, characterised in that after step e) the set actuator energy and the current rail pressure are stored as a measure for the idle stroke of the injector.
  8. Method according to claim 7, characterised in that after the energy and rail pressure values are saved the steps b) to e) are performed, with the actuator energy being set to an initial value beforehand.
  9. Method according to one of the preceding claims, characterised in that during a coasting phase of the internal combustion engine a constant rail pressure or a continuous drop in rail pressure is set in step a).
  10. Method according to claim 9, characterised in that after step e) the pressure in the rail is increased to a desired adjustment value.
  11. Device for detecting the idle stroke of injectors of an internal combustion engine having a common rail system comprises a fuel pressure accumulator, an injector connected to the fuel pressure accumulator, a rail pressure sensor and a control unit for the actuators of the injectors, wherein the control unit changes the actuator energy until the rail pressure sensor detects a discontinuity in the variation of the rail pressure over time, and wherein the device has a memory unit for storing the actuator energy value present during the discontinuity and the rail pressure value present.
EP05777858A 2004-09-14 2005-07-21 Method and device for characterising a return stroke of injectors Expired - Fee Related EP1789675B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102004044450A DE102004044450B3 (en) 2004-09-14 2004-09-14 Method and device for idle detection of injectors
PCT/EP2005/053554 WO2006029931A1 (en) 2004-09-14 2005-07-21 Method and device for characterising a return stroke of injectors

Publications (2)

Publication Number Publication Date
EP1789675A1 EP1789675A1 (en) 2007-05-30
EP1789675B1 true EP1789675B1 (en) 2008-06-25

Family

ID=35058399

Family Applications (1)

Application Number Title Priority Date Filing Date
EP05777858A Expired - Fee Related EP1789675B1 (en) 2004-09-14 2005-07-21 Method and device for characterising a return stroke of injectors

Country Status (5)

Country Link
US (1) US7406861B2 (en)
EP (1) EP1789675B1 (en)
CN (1) CN100504061C (en)
DE (2) DE102004044450B3 (en)
WO (1) WO2006029931A1 (en)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006039522B4 (en) * 2006-08-23 2009-01-29 Continental Automotive Gmbh Method for the Leerhubsteuerung a fuel injection device
DE102007034188A1 (en) * 2007-07-23 2009-01-29 Robert Bosch Gmbh Method for operating an injection valve
DE102007052092B4 (en) 2007-10-31 2011-06-01 Continental Automotive Gmbh Method and fuel system for controlling the fuel supply for an internal combustion engine
DE102008029799A1 (en) 2008-06-24 2009-12-31 Continental Automotive Gmbh Injector controlling method for common rail diesel internal-combustion engine, involves determining control signal level, while control signal basic value is added with addition value dependent of temperature and/or pressure in accumulator
DE102010021168B4 (en) * 2010-05-21 2020-06-25 Continental Automotive Gmbh Method for operating an internal combustion engine and internal combustion engine
DE102010039841B4 (en) 2010-08-26 2014-01-09 Continental Automotive Gmbh Method for adjusting the injection characteristic of an injection valve
DE102011005285B4 (en) 2011-03-09 2015-08-20 Continental Automotive Gmbh Method for determining the idle stroke of a piezo injector with directly actuated nozzle needle
DE102011081161A1 (en) 2011-08-18 2013-02-21 Continental Automotive Gmbh Control and driving method for a piezoelectric actuator
DE102011083068A1 (en) * 2011-09-20 2013-03-21 Robert Bosch Gmbh Method for determining a value of a stream
DE102012208614A1 (en) 2012-05-23 2013-11-28 Robert Bosch Gmbh Method for operating a fuel system for an internal combustion engine
DE102013201777A1 (en) 2013-02-04 2014-08-07 Robert Bosch Gmbh Method for driving injector of internal combustion engine in common rail injection system or fuel injection system, involves correcting deviating time for control start of injector individually, if zero stroke is reached at preset voltage
DE102013205504B4 (en) 2013-03-27 2019-02-07 Continental Automotive Gmbh Determining the opening energy of a fuel injector
DE102013206674A1 (en) * 2013-04-15 2014-10-16 Robert Bosch Gmbh Method and device for controlling a quantity control valve
FR3013392B1 (en) 2013-11-21 2017-12-29 Continental Automotive France METHOD FOR MONITORING A FUEL INJECTOR OF AN INTERNAL COMBUSTION ENGINE OF A VEHICLE

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3128238C2 (en) * 1981-07-17 1986-11-06 Pierburg Gmbh & Co Kg, 4040 Neuss Method and device for determining the amount of fuel injected
US5535621A (en) * 1994-03-02 1996-07-16 Ford Motor Company On-board detection of fuel injector malfunction
US5633458A (en) * 1996-01-16 1997-05-27 Ford Motor Company On-board fuel delivery diagnostic system for an internal combustion engine
JPH11101149A (en) * 1997-09-26 1999-04-13 Isuzu Motors Ltd Fuel injection method and device thereof for engine
DE19757293C2 (en) * 1997-12-22 1999-11-25 Siemens Ag Device for determining the start of injection in a direct injection internal combustion engine
DE19902807C1 (en) * 1999-01-25 2000-06-08 Siemens Ag Play setting between actuator and servovalve driven by actuator in fuel injector
DE19905340C2 (en) * 1999-02-09 2001-09-13 Siemens Ag Method and arrangement for presetting and dynamic tracking of piezoelectric actuators
US6420817B1 (en) * 2000-02-11 2002-07-16 Delphi Technologies, Inc. Method for detecting injection events in a piezoelectric actuated fuel injector
DE10014737A1 (en) * 2000-03-24 2001-10-11 Bosch Gmbh Robert Method for determining the rail pressure of an injection valve with a piezoelectric actuator
GB2366598A (en) * 2000-09-07 2002-03-13 Cummins Engine Co Ltd Detecting leakage in the fuel rail of an i.c. engine
GB0104215D0 (en) * 2001-02-21 2001-04-11 Delphi Tech Inc Control method
US7188608B2 (en) * 2001-12-11 2007-03-13 Caterpillar Inc. Rail pressure sampling before fuel injection events
JP2003328835A (en) * 2002-05-14 2003-11-19 Mitsubishi Electric Corp Fuel pressure sensor device for internal combustion engine control system
JP2005030342A (en) * 2003-07-09 2005-02-03 Denso Corp Common-rail type fuel injector
US7040149B2 (en) * 2003-10-24 2006-05-09 Senx Technology, Llc Fuel injection system diagnostic system
JP4321342B2 (en) * 2004-04-22 2009-08-26 株式会社デンソー Common rail fuel injection system

Also Published As

Publication number Publication date
US7406861B2 (en) 2008-08-05
EP1789675A1 (en) 2007-05-30
CN101018945A (en) 2007-08-15
CN100504061C (en) 2009-06-24
US20070204832A1 (en) 2007-09-06
WO2006029931A1 (en) 2006-03-23
DE102004044450B3 (en) 2006-04-06
DE502005004537D1 (en) 2008-08-07

Similar Documents

Publication Publication Date Title
EP1789675B1 (en) Method and device for characterising a return stroke of injectors
DE102008036122B4 (en) Method for adapting the power of a fuel feed pump of a motor vehicle
DE102004053124B4 (en) Valve opening degree control system and common rail fuel injection system
DE102006027405B3 (en) Method for operating an internal combustion engine and internal combustion engine
DE102008044144B4 (en) Fuel injection control apparatus and method for controlling an injection characteristic of a fuel injection valve
WO2007134887A1 (en) Method and device for controlling an injection valve of an internal combustion engine
DE102008040059A1 (en) Fuel injection control unit
DE102014107903B4 (en) Technology for determining the injection behavior of a fuel injector
WO2009056402A1 (en) Method for identifying a type of fuel
EP0811116A1 (en) Process and device for monitoring a fuel metering system of an internal combustion engine
DE102008055747B4 (en) Method and device for operating an injection system for an internal combustion engine
DE102011077404B4 (en) Method for determining the fuel type in a high-pressure injection device of an internal combustion engine
DE19731994A1 (en) Method and device for controlling an internal combustion engine
DE102005052958B4 (en) Common Rail Fuel Injection System
EP2054606A1 (en) Method for the determination of a rail pressure nominal value
EP2035676A1 (en) Method and device for adapting the valve characteristic of a fuel injection valve
DE102005043684A1 (en) Fuel system controlling method for e.g. diesel engine, involves controlling fuel pump during overrun fuel cut off of engine with pre-control value, such that output pressure of fuel is set above null discharging pressure
EP1438495A1 (en) Method, computer program, control and regulating appliance for operating an internal combustion engine, and internal combustion engine
DE10341775A1 (en) Common rail injection system for road vehicle has electronic control unit with pressure sensor and providing individual electrical control signals for injectors to give small pilot injections
DE19731201C2 (en) Method for regulating the fuel pressure in a fuel accumulator
DE102007040122A1 (en) Method and device for controlling a pump connected to a fuel rail
EP1826396A1 (en) Common rail fuel injection system
DE10302058B4 (en) Method for operating an internal combustion engine
DE102007015876A1 (en) Drift and malfunctioning recognition method for rail pressure sensor, involves determining pressure of rail pressure sensor as function of control duration difference between pressure multiplication and non-pressure multiplication injection
DE19917711C2 (en) Method and device for controlling an internal combustion engine

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20070307

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR

DAX Request for extension of the european patent (deleted)
RBV Designated contracting states (corrected)

Designated state(s): DE FR

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: CONTINENTAL AUTOMOTIVE GMBH

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR

REF Corresponds to:

Ref document number: 502005004537

Country of ref document: DE

Date of ref document: 20080807

Kind code of ref document: P

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20080715

Year of fee payment: 4

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20090326

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20100331

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20090731

REG Reference to a national code

Ref country code: DE

Ref legal event code: R084

Ref document number: 502005004537

Country of ref document: DE

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 502005004537

Country of ref document: DE

Owner name: VITESCO TECHNOLOGIES GMBH, DE

Free format text: FORMER OWNER: CONTINENTAL AUTOMOTIVE GMBH, 30165 HANNOVER, DE

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20200731

Year of fee payment: 16

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 502005004537

Country of ref document: DE

Owner name: VITESCO TECHNOLOGIES GMBH, DE

Free format text: FORMER OWNER: VITESCO TECHNOLOGIES GMBH, 30165 HANNOVER, DE

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 502005004537

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20220201