EP2971746B1 - Method for venting a fuel supply line, and internal combustion engine - Google Patents

Method for venting a fuel supply line, and internal combustion engine Download PDF

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Publication number
EP2971746B1
EP2971746B1 EP14708482.6A EP14708482A EP2971746B1 EP 2971746 B1 EP2971746 B1 EP 2971746B1 EP 14708482 A EP14708482 A EP 14708482A EP 2971746 B1 EP2971746 B1 EP 2971746B1
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EP
European Patent Office
Prior art keywords
fuel
internal combustion
combustion engine
pressure
injector
Prior art date
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Active
Application number
EP14708482.6A
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German (de)
French (fr)
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EP2971746A1 (en
Inventor
Marc Radl
Klaus Reischmann
Michael Willmann
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.)
Rolls Royce Solutions GmbH
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MTU Friedrichshafen GmbH
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Publication of EP2971746A1 publication Critical patent/EP2971746A1/en
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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
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/04—Introducing corrections for particular operating conditions
    • F02D41/06—Introducing corrections for particular operating conditions for engine starting or warming up
    • 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
    • F02D41/06—Introducing corrections for particular operating conditions for engine starting or warming up
    • F02D41/062—Introducing corrections for particular operating conditions for engine starting or warming up for starting
    • 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
    • F02D41/3836—Controlling the fuel pressure
    • F02D41/3845—Controlling the fuel pressure by controlling the flow into the common rail, e.g. the amount of fuel pumped
    • 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
    • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
    • F02M37/0011—Constructional details; Manufacturing or assembly of elements of fuel systems; Materials therefor
    • F02M37/0023—Valves in the fuel supply and return system
    • 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
    • F02M55/00—Fuel-injection apparatus characterised by their fuel conduits or their venting means; Arrangements of conduits between fuel tank and pump F02M37/00
    • F02M55/007—Venting 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
    • F02M55/00—Fuel-injection apparatus characterised by their fuel conduits or their venting means; Arrangements of conduits between fuel tank and pump F02M37/00
    • F02M55/02—Conduits between injection pumps and injectors, e.g. conduits between pump and common-rail or conduits between common-rail and injectors
    • F02M55/025—Common rails

Definitions

  • the invention relates to a method for venting a fuel supply line according to the preamble of claim 1 and to an internal combustion engine having a direct injection system according to the preamble of claim 9.
  • a direct injection system of an internal combustion engine typically has at least one injector, with which fuel is injected into a combustion chamber of the internal combustion engine. It is provided a fuel supply line, via which the injector fuel is supplied. Upstream of the injector, a high-pressure accumulator is provided, which is also referred to as a so-called common rail, common rail. If the internal combustion engine has several injectors, these are preferably supplied with fuel from the common high-pressure accumulator. To promote fuel in the high pressure accumulator, a high pressure pump is provided. A pressure in the high-pressure accumulator is regulated by means of an intake throttle arranged upstream of the high-pressure pump.
  • a quantity limiting valve is arranged between the high-pressure accumulator and the injector, which supplies an amount of fuel flowing from the high-pressure accumulator to the injector limited. If the injector malfunctions, so that too much fuel tends to flow into the combustion chamber, the flow control valve will respond, interrupting fluid communication between the high pressure accumulator and the defective injector.
  • the fuel supply line in particular vented downstream of the flow control valve.
  • the air is compressed in the fuel supply line. Since a large volume of air must be displaced in this case, when filling the vented fuel supply line, a large amount of fuel flows through the flow control valve. This can thereby address unintentionally.
  • the injector which is assigned to the flow control valve, only a small amount of fuel or no more supplied. This leads to a reduced performance and a non-circular running of the internal combustion engine. It may then be necessary to completely shut them down several times and to relax the fuel supply line.
  • From the EP 1 314 883 A2 is a common rail system with multiple rails known.
  • a purge valve is opened in a first step, and in a second step, the fuel is then conveyed from the low-pressure pump via the throttle valves to the high-pressure pumps.
  • the high-pressure pumps pump the fuel back to the fuel tank via a pump reservoir, the rails and the flushing valve.
  • the flushing process is used to preheat a cold internal combustion engine, which is to be started with heavy oil.
  • the invention is therefore an object of the invention to provide a method and an internal combustion engine, which do not have the disadvantages described, in particular, a venting of the fuel supply line should be possible, in which an inadmissible response of a quantity limiting valve is avoided.
  • the object is achieved by providing a method with the steps of claim 1.
  • the method is characterized in that the fuel supply line is vented downstream of the high pressure pump, wherein in the suction throttle during a bleed operation, a passage cross-section is set for the fuel, which is less than or equal to a predetermined limit passage cross-section.
  • the limit passage cross section is smaller than a maximum passage cross section of the suction throttle.
  • the passage cross section of the suction throttle is selected in the venting operation so that a piston of the flow control valve does not reach its blocking position during venting.
  • the air in the fuel supply line is compressed and goes into solution in the subsequent engine run or is discharged into a combustion chamber of the internal combustion engine.
  • An impermissible response of the quantity limiting valve is therefore avoided by a reduced amount of fuel is conveyed in the venting operation by means of the high-pressure pump.
  • a method is also preferred, which is characterized in that the venting operation is performed when starting the internal combustion engine.
  • the venting operation is performed at a first start of the internal combustion engine.
  • the venting operation is performed after a maintenance or repair of the internal combustion engine.
  • the bleeding operation is performed when the fuel supply pipe is vented downstream of the high-pressure accumulator.
  • a Senstechniksmittel is provided with the help of which it is determined in particular when starting whether the fuel supply line is vented downstream of the high-pressure accumulator. If this is determined, the bleeding operation is performed when starting the internal combustion engine.
  • the internal combustion engine is preferably started in a normal start-up operation.
  • the passage cross-section of the suction throttle is set to a maximum value in order to achieve a predetermined pressure in the high-pressure accumulator as quickly as possible.
  • the bleeding operation thus differs from the normal start-up operation precisely in that, contrary to the conventional approach, in which a predetermined pressure in the high-pressure accumulator is sought as quickly as possible by maximizing the fuel delivery, the passage cross-section for the fuel in the Suction throttle is limited in order to limit the fuel flow to a value at which the flow control valve does not respond inadmissible.
  • a method is preferred which is characterized in that the suction throttle is controlled by an engine control unit of the internal combustion engine.
  • an algorithm is preferably implemented by means of which the pressure in the high-pressure accumulator can be controlled and / or regulated during normal operation of the internal combustion engine, wherein the passage cross section of the intake throttle is preferably maximized in a normal start-up operation of the internal combustion engine, the intake throttle thus completely is controlled in order to reach the predetermined pressure as quickly as possible.
  • an algorithm is further preferably implemented, which makes it possible to carry out the venting operation, in which the passage cross section of the suction throttle is set smaller than or equal to the predetermined limit passage cross section.
  • the engine control unit is preferably operatively connected to the suction throttle for driving.
  • a method is also preferred, which is characterized in that the bleeding operation is terminated as soon as the fuel supply line is vented.
  • the venting operation is terminated by the fact that the suction throttle - preferably by the engine control unit - is controlled to control the pressure in the high-pressure accumulator. It is thus changed to terminate the venting operation, the control of the suction throttle, which is no longer maintained on a passage cross-section less than or equal to the predetermined Grenz bestorysquerêt, but by being controlled such that a regulation of the pressure takes place in the high-pressure accumulator.
  • After targeted execution of the bleeding operation is therefore preferably switched to a normal operation of the internal combustion engine.
  • the end of the bleeding operation is preferably detected by the sensing means by which it can be determined whether the fuel supply line is vented downstream of the high-pressure accumulator.
  • a method is preferred which is characterized in that the predetermined limit passage cross section is selected to be 50%, preferably 25%, preferably 15%, preferably 10%, preferably 5%, preferably 2%, preferably 1% of a maximum passage cross section of the suction throttle.
  • the Suction choke is preferably designed so that their passage cross-section between a minimum passage cross-section and a maximum passage cross-section is gradually or preferably continuously variable.
  • the limit passage cross-section ensures that in the venting mode only such an amount of fuel is conveyed by the high-pressure pump, in which the flow control valve does not respond inadmissible. It is possible that the predetermined and preferably stored in the engine control unit limiting passage cross-section is selected depending on a used in the engine mass limiting valve.
  • This procedure is based on the idea that different quantity-limiting valves respond at different values of a fuel flow flowing over them, so that preferably the limit passage cross-section is matched to a specifically installed quantity-limiting valve.
  • the predetermined boundary passage cross-section is preferably matched to the specifically used suction throttle and a specifically used flow control valve, so that it is ensured that during the bleeding operation no unacceptably high flow rate flows through the flow control valve to prevent its response.
  • a method is also preferred which is characterized in that an engine speed of the internal combustion engine during the bleeding operation at about 100 revolutions per minute (rpm) is maintained. This value is preferably below an idle speed of the internal combustion engine. As a result, the delivery rate of the high-pressure pump is additionally reduced, which is advantageous for the venting operation.
  • a method is also preferred which is characterized in that a pressure is sensed downstream of the flow control valve.
  • a pressure sensor is preferably provided downstream of the quantity limiting valve in the fuel supply line. This is preferably operatively connected to the engine control unit, so that it can evaluate the pressure detected by the pressure sensor and use to control the internal combustion engine.
  • the fuel supply line is vented.
  • a method is also preferred, which is characterized in that the high-pressure pump is driven by the internal combustion engine at the engine speed.
  • the high-pressure pump is operatively connected directly to the internal combustion engine in such a way that, in each operating state, it has the same rotational speed as the latter.
  • the pressure in the high pressure accumulator is controlled by means of the suction throttle, because the delivery rate of the high pressure pump varies depending on the speed of the internal combustion engine.
  • an internal combustion engine having the features of claim 9.
  • This comprises a direct injection system which has at least one injector for injecting fuel into a combustion chamber of the internal combustion engine. Upstream of the injector, a high pressure accumulator is provided which is in fluid communication with the injector for supplying the injector with fuel. A quantity limiting valve is disposed in fluid communication between the high pressure accumulator and the injector to limit an amount of fuel flowing from the engine accumulator to the injector.
  • a high pressure pump is provided for delivering fuel into the high pressure accumulator upstream thereof, and a pressure in the high pressure accumulator upstream of the high pressure pump is controllable by a suction throttle. The suction throttle can be controlled by an engine control unit of the internal combustion engine.
  • the internal combustion engine is characterized in that the engine control unit for venting the fuel supply line downstream of the high-pressure pump adjusts the suction throttle during a bleeding operation to a passage cross-section for the fuel which is less than or equal to a predetermined limit passage cross-section.
  • the boundary passage cross section in turn is smaller than the maximum passage cross section of the suction throttle, wherein the passage cross section of the suction throttle is selected in the bleeding mode so that a piston of the flow control valve does not reach its blocking position during venting.
  • the suction throttle is integrated in one embodiment of the internal combustion engine in the high-pressure pump.
  • the suction throttle is arranged as a separate element upstream of the high-pressure pump in the fuel supply line.
  • An internal combustion engine is also preferred, which is characterized in that the at least one injector has an internal fuel reservoir. This does not replace the high-pressure reservoir, but is provided in addition to this.
  • the flow control valve is integrated into the injector.
  • the quantity limiting valve is provided as a separate element upstream of the injector.
  • an internal combustion engine is preferred which is characterized by at least one feature that is due to at least one method step, preferably combinations thereof, of an embodiment of the method.
  • a method is preferred which is characterized by at least one method step, which results from at least one feature of the internal combustion engine, preferably combinations thereof. All features described in connection with the method are preferably individually or in combination with each other features of an embodiment of the internal combustion engine. Likewise, all of the method steps described in connection with the internal combustion engine are preferably individually or in combination with one another steps of an embodiment of the method.
  • the figure shows a schematic representation of a direct injection system 1 of an embodiment of an internal combustion engine.
  • the direct injection system 1 has an injector 3 through which fuel 7 can be injected into a combustion chamber, not shown, of the internal combustion engine by means of a valve device 5 shown schematically.
  • the injector 3 also includes an internal fuel reservoir 9.
  • a fuel supply line 11 serves to convey fuel from a fuel tank 13, preferably a tank, to the injector 3. Upstream of the injector 3, a high-pressure accumulator 15 is arranged, from which the injector 3 is supplied with fuel. Between the high-pressure accumulator 15 and the injector 3, a quantity limiting valve 17 is arranged in the fuel supply line 11 in order to protect the internal combustion engine against an inadmissibly high amount of fuel which could be introduced into the combustion chamber via a defective injector 3. The operation of the quantity limiting valve 17 will be explained in more detail below.
  • a high-pressure pump 19 For conveying fuel into the high-pressure accumulator 15, a high-pressure pump 19 is arranged in the fuel line 11 upstream thereof. Their delivery rate is controlled by a suction throttle 21 arranged upstream of the high-pressure pump 19, wherein in particular the pressure in the high-pressure accumulator 15 is regulated by means of the suction throttle 21.
  • the suction throttle 21 is shown here schematically as separate from the high-pressure pump 19 valve device. However, it is quite possible that the suction throttle 21 is formed as part of the high pressure pump 19 or integrated into it.
  • a passage cross-section of the suction throttle 21 is continuously variable between a minimum value and a maximum value. It is possible that the minimum value of the passage cross section corresponds to a closed position of the suction throttle 21, so that in this case no fuel can be conveyed via the suction throttle 21.
  • a low-pressure pump 23 is provided, which serves to convey fuel from the reservoir 13 via a filter 25 to the suction throttle 21.
  • the quantity limiting valve 17 has a flow-limiting device 27 and a compensating volume 29 arranged downstream of it, wherein the compensating volume 29 preferably comprises a throttle device 31.
  • the flow-limiting device 27 comprises in the illustrated embodiment a displaceable in a cylinder 33 piston 35 which is biased in the position indicated by A by a spring element 37.
  • a fixed throttle 39 is schematically indicated that in the region of the piston 35, a predetermined passage cross-section is provided for fuel. It is possible that the fuel through a bore in the piston 35 - as indicated in the figure by the fixed throttle 39 - can flow through. In another embodiment, it is possible that the fuel may flow past the piston 35 laterally. Other embodiments, the function of the fixed throttle 39 to realize, are possible.
  • the piston 35 is displaceable from its stop position shown at A via a middle position shown at B against the biasing force of the spring element 37 to a stop position shown at C.
  • the quantity limiting valve 17 is arranged in a blocking position in this case, so that no more fuel can flow from the high-pressure accumulator 15 to the injector 3.
  • the fuel supply line 11 is completely filled with substantially incompressible fuel.
  • the pressure in the high-pressure accumulator 15 is regulated by means of the suction throttle 21. If the valve device 5 of the injector 3 is closed, no fuel flows from the high-pressure accumulator 15 via the quantity limiting valve 17 to the injector 3. If an injection of fuel 7 into the combustion chamber assigned to the injector 3 is carried out by means of the injector 3, fuel 7 flows over the valve device 5 from, whereby at the same time results in a fuel flow from the high-pressure accumulator 15 to the injector 3 via the flow control valve 17.
  • the valve device 5 If due to a malfunction of the injector 3, the valve device 5 is not or not closed in time, the pressure in the internal memory 9 or in the fuel supply line 11 downstream of the flow control valve 17 continues to fall, and the compensation volume 29 is further reduced by the piston 35 on the position B out - in the figure - shifted to the right. Because of the fixed throttle 39, in fact not enough fuel per unit of time can flow in order to compensate for the fuel outflow via the valve device 5. When the injection lasts, the piston 35 finally reaches the position shown at C in which the fluid communication between the high-pressure accumulator 15 and the injector 3 is blocked. It can then no longer flow of fuel from the high-pressure accumulator 15, so that the compensating volume 29, possibly the internal memory 9 and the injector 3 idles into the combustion chamber.
  • the pressure drops in the region of the injector 3, so that the piston 35 is permanently held by the pressure difference between the high-pressure accumulator 15 on the one hand and the injector 3 on the other hand in the blocking position shown at C.
  • the quantity limiting valve 17 is therefore permanently locked, and it can not be introduced inadmissible amount of fuel through the defective injector 3 in the combustion chamber.
  • the internal combustion engine is protected from damage caused by an excessive amount of energy.
  • the fuel supply line 11 ventilated all or at least downstream of the flow control valve 17 ventilated all or at least downstream of the flow control valve 17.
  • the passage cross section of the suction throttle 21st set at a normal start-up operation of the internal combustion engine to a maximum, so that a predetermined pressure in the high-pressure accumulator 15 sets as soon as possible. Since the fixed throttle 39 is a flow obstacle, above the piston 35, a pressure drops.
  • the piston 35 moves due to the pressure difference rapidly against the biasing force of the spring element 37 - in the figure - to the right, the flowing over the fixed throttle 39 per unit time Fuel volume is insufficient to compensate for the compression in the compensation volume 29. Therefore, there is a risk that the piston 35 reaches the position shown at C, whereby the flow control valve 17 responds and permanently blocks the fluid communication between the high pressure accumulator 15 and the injector 3. It is then no longer possible injection through the injector 3. This leads to a lack of power and / or to a non-circular engine running of the internal combustion engine. The internal combustion engine may then have to be shut down completely several times, and the fuel supply line 11 must be expanded upstream of the flow control valve 17, because otherwise no return displacement of the piston 35 in the position A can be achieved.
  • a compressible medium in particular air
  • the suction throttle 21 is controlled so that it only has a passage cross-section which is smaller than or equal to a predetermined limit passage cross-section.
  • the limit passage cross-section is preferably smaller than a passage cross-section typically assumed by the suction throttle 21 during normal operation of the internal combustion engine, and in particular smaller, preferably much smaller, than the maximum passage cross-section occupied by a normal starting of the internal combustion engine. In this way, the amount of fuel delivered by the high-pressure pump 19 is limited so that the fuel supply line 11 upstream of the high-pressure pump 19 is slowly filled with fuel.
  • the passage cross section of the suction throttle 21 is set in the venting operation so that the amount of fuel delivered by the high pressure pump 19 until the end of the bleeding mode just corresponds to the flow rate flowing through the fixed throttle 39.
  • the passage cross section of the suction throttle 21 in the venting operation is preferably selected so that the piston 35 does not move, only very slowly, or at most only as quickly in the direction of its stop position shown in C that the venting of the fuel supply line 11 is completed is before the piston 35 reaches its locking position. In this way it is ensured that the piston 35 does not reach its locking position during venting.
  • the speed of the internal combustion engine is preferably maintained at approximately 100 rpm during the bleeding operation. Upon completion of the bleed operation, it is preferably increased to an idle speed that is, for example, about 350 rpm.
  • the high-pressure pump 19 is preferably driven by the speed of the internal combustion engine, which is preferably reduced during the bleeding operation, the delivery of the high-pressure pump 19 is limited beyond the control of the suction throttle 21, which makes the bleeding operation particularly safe.

Description

Die Erfindung betrifft ein Verfahren zur Entlüftung einer Kraftstoffversorgungsleitung gemäß Oberbegriff des Anspruchs 1 sowie eine Brennkraftmaschine mit einem Direkt-Einspritzungssystem gemäß Oberbegriff des Anspruchs 9.The invention relates to a method for venting a fuel supply line according to the preamble of claim 1 and to an internal combustion engine having a direct injection system according to the preamble of claim 9.

Verfahren und Brennkraftmaschinen der hier angesprochenen Art sind bekannt. Ein Direkt-Einspritzungssystem einer Brennkraftmaschine weist typischerweise mindestens einen Injektor auf, mit dem Kraftstoff in eine Brennkammer der Brennkraftmaschine eingespritzt wird. Es ist eine Kraftstoffversorgungsleitung vorgesehen, über die dem Injektor Kraftstoff zuführbar ist. Stromaufwärts des Injektors ist ein Hochdruck-Speicher vorgesehen, der auch als sogenannte gemeinsame Leiste, Common Rail, bezeichnet wird. Weist die Brennkraftmaschine mehrere Injektoren auf, werden diese vorzugsweise alle aus dem gemeinsamen Hochdruck-Speicher mit Kraftstoff versorgt. Zur Förderung von Kraftstoff in den Hochdruck-Speicher ist eine Hochdruckpumpe vorgesehen. Ein Druck in dem Hochdruck-Speicher wird mittels einer stromaufwärts der Hochdruckpumpe angeordneten Saugdrossel geregelt. Um zu verhindern, dass die Brennkraftmaschine durch eine unzulässige Zufuhr von Kraftstoff durch einen defekten, nicht mehr korrekt schließenden Injektor beschädigt wird, ist zwischen dem Hochdruck-Speicher und dem Injektor ein Mengenbegrenzungsventil angeordnet, das eine von dem Hochdruck-Speicher zu dem Injektor strömende Kraftstoffmenge begrenzt. Weist der Injektor eine Fehlfunktion auf, sodass tendenziell zu viel Kraftstoff in die Brennkammer strömt, spricht das Mengenbegrenzungsventil an und unterbricht die Fluidverbindung zwischen dem Hochdruck-Speicher und dem defekten Injektor.Method and internal combustion engines of the type discussed here are known. A direct injection system of an internal combustion engine typically has at least one injector, with which fuel is injected into a combustion chamber of the internal combustion engine. It is provided a fuel supply line, via which the injector fuel is supplied. Upstream of the injector, a high-pressure accumulator is provided, which is also referred to as a so-called common rail, common rail. If the internal combustion engine has several injectors, these are preferably supplied with fuel from the common high-pressure accumulator. To promote fuel in the high pressure accumulator, a high pressure pump is provided. A pressure in the high-pressure accumulator is regulated by means of an intake throttle arranged upstream of the high-pressure pump. In order to prevent the internal combustion engine from being damaged by an impermissible supply of fuel by a defective, incorrectly closing injector, a quantity limiting valve is arranged between the high-pressure accumulator and the injector, which supplies an amount of fuel flowing from the high-pressure accumulator to the injector limited. If the injector malfunctions, so that too much fuel tends to flow into the combustion chamber, the flow control valve will respond, interrupting fluid communication between the high pressure accumulator and the defective injector.

Bei einem Erststart der Brennkraftmaschine oder auch nach einer Wartung oder Reparatur ist es möglich, dass die Kraftstoffversorgungsleitung insbesondere stromabwärts des Mengenbegrenzungsventils belüftet ist. Beim Starten der Brennkraftmaschine wird in diesem Fall die Luft in der Kraftstoffversorgungsleitung komprimiert. Da hierbei ein großes Luftvolumen verdrängt werden muss, fließt beim Füllen der belüfteten Kraftstoffversorgungsleitung eine große Menge Kraftstoff über das Mengenbegrenzungsventil. Dieses kann hierdurch ungewollt ansprechen. Daraufhin wird dem Injektor, der dem Mengenbegrenzungsventil zugeordnet ist, nur noch eine geringe oder gar keine Kraftstoffmenge mehr zugeführt. Dies führt zu einer verminderten Leistung und zu einem unrunden Lauf der Brennkraftmaschine. Es ist dann gegebenenfalls nötig, diese mehrfach komplett herunterzufahren und die Kraftstoffversorgungsleitung zu entspannen. Aus der DE 103 42 116 B4 geht ein Verfahren zum Entlüften einer Kraftstoffeinspritzleitung hervor, bei dem ein Injektor in einem Entlüftungsbetrieb sehr viel länger offengehalten wird, als bei einem normalen Einspritzbetrieb. Auf diese Weise wird ein Abfluss von Luft aus der Kraftstoffeinspritzleitung in Zylinder der Brennkraftmaschine hinein ermöglicht. Auch hierbei ist es jedoch noch möglich, dass ein stromaufwärts des Injektors angeordnetes Mengenbegrenzungsventil unzulässigerweise anspricht, wodurch sich die bereits beschriebenen Probleme ergeben.At a first start of the internal combustion engine or after a maintenance or repair, it is possible that the fuel supply line in particular vented downstream of the flow control valve. When starting the internal combustion engine in this case, the air is compressed in the fuel supply line. Since a large volume of air must be displaced in this case, when filling the vented fuel supply line, a large amount of fuel flows through the flow control valve. This can thereby address unintentionally. Then, the injector, which is assigned to the flow control valve, only a small amount of fuel or no more supplied. This leads to a reduced performance and a non-circular running of the internal combustion engine. It may then be necessary to completely shut them down several times and to relax the fuel supply line. From the DE 103 42 116 B4 discloses a method for venting a fuel injection line in which an injector is kept open much longer in a venting operation than in a normal injection operation. In this way, an outflow of air from the fuel injection line into cylinders of the internal combustion engine is made possible. However, in this case too, it is still possible for a quantity-limiting valve arranged upstream of the injector to respond inappropriately, which results in the problems already described.

Aus der EP 1 314 883 A2 ist ein Common-Railsystem mit mehreren Rails bekannt. Beim Spülvorgang wird in einem ersten Schritt ein Spülventil geöffnet und in einem zweiten Schritt wird dann der Kraftstoff von der Niederdruckpumpe über die Drosselventile zu den Hochdruckpumpen gefördert. Von den Hochdruckpumpen wiederum wird der Kraftstoff über einen Pumpspeicher, den Rails und über das Spülventil zurück zum Kraftstofftank gepumpt. Der Spülvorgang dient zur Vorwärmung einer kalten Brennkraftmaschine, die mit Schweröl gestartet werden soll.From the EP 1 314 883 A2 is a common rail system with multiple rails known. During the rinsing process, a purge valve is opened in a first step, and in a second step, the fuel is then conveyed from the low-pressure pump via the throttle valves to the high-pressure pumps. The high-pressure pumps, in turn, pump the fuel back to the fuel tank via a pump reservoir, the rails and the flushing valve. The flushing process is used to preheat a cold internal combustion engine, which is to be started with heavy oil.

Der Erfindung liegt daher die Aufgabe zugrunde, ein Verfahren und eine Brennkraftmaschine zu schaffen, welche die beschriebenen Nachteile nicht aufweisen, wobei insbesondere eine Entlüftung der Kraftstoffversorgungsleitung möglich sein soll, bei welcher ein unzulässiges Ansprechen eines Mengenbegrenzungsventils vermieden wird.The invention is therefore an object of the invention to provide a method and an internal combustion engine, which do not have the disadvantages described, in particular, a venting of the fuel supply line should be possible, in which an inadmissible response of a quantity limiting valve is avoided.

Die Aufgabe wird gelöst, indem ein Verfahren mit den Schritten des Anspruchs 1 geschaffen wird.The object is achieved by providing a method with the steps of claim 1.

Das Verfahren zeichnet sich dadurch aus, dass die Kraftstoffversorgungsleitung stromabwärts der Hochdruckpumpe entlüftet wird, wobei in der Saugdrossel während eines Entlüftungsbetriebs ein Durchtrittsquerschnitt für den Kraftstoff eingestellt wird, der kleiner oder gleich einem vorherbestimmten Grenzdurchtrittsquerschnitt ist. Der Grenzdurchtrittsquerschnitt ist jedenfalls kleiner als ein maximaler Durchtrittsquerschnitt der Saugdrossel. Der Durchtrittsquerschnitt der Saugdrossel wird im Entlüftungsbetrieb so gewählt, dass ein Kolben des Mengenbegrenzungsventils seine Sperrposition während des Entlüftens nicht erreicht. Beim Entlüftungsbetrieb ergibt sich so eine reduzierte Fördermenge der Hochdruckpumpe, sodass nur ein kleiner Volumenstrom gefördert wird, der entsprechend über das mindestens eine Mengenbegrenzungsventil fließen kann. Dieses spricht daher nicht unzulässig an, und die Kraftstoffversorgungsleitung wird zuverlässig entlüftet beziehungsweise mit Kraftstoff gefüllt. Die Luft in der Kraftstoffversorgungsleitung wird komprimiert und geht im nachfolgenden Motorlauf in Lösung beziehungsweise wird in eine Brennkammer der Brennkraftmaschine abgeführt. Ein unzulässiges Ansprechen des Mengenbegrenzungsventils wird demnach vermieden, indem im Entlüftungsbetrieb eine reduzierte Kraftstoffmenge mittels der Hochdruckpumpe gefördert wird.The method is characterized in that the fuel supply line is vented downstream of the high pressure pump, wherein in the suction throttle during a bleed operation, a passage cross-section is set for the fuel, which is less than or equal to a predetermined limit passage cross-section. In any case, the limit passage cross section is smaller than a maximum passage cross section of the suction throttle. The passage cross section of the suction throttle is selected in the venting operation so that a piston of the flow control valve does not reach its blocking position during venting. When venting operation results in a reduced flow rate of the high-pressure pump, so that only a small volume flow is promoted, which can flow according to the at least one flow control valve. This is therefore not inadmissible, and the fuel supply line is reliably vented or filled with fuel. The air in the fuel supply line is compressed and goes into solution in the subsequent engine run or is discharged into a combustion chamber of the internal combustion engine. An impermissible response of the quantity limiting valve is therefore avoided by a reduced amount of fuel is conveyed in the venting operation by means of the high-pressure pump.

Es wird auch ein Verfahren bevorzugt, das sich dadurch auszeichnet, dass der Entlüftungsbetrieb beim Starten der Brennkraftmaschine durchgeführt wird. Bevorzugt wird der Entlüftungsbetrieb bei einem Erststart der Brennkraftmaschine durchgeführt. Alternativ oder zusätzlich ist vorgesehen, dass der Entlüftungsbetrieb nach einer Wartung oder Reparatur der Brennkraftmaschine durchgeführt wird. Insbesondere wird der Entlüftungsbetrieb durchgeführt, wenn die Kraftstoffversorgungsleitung stromabwärts des Hochdruck-Speichers belüftet ist. Vorzugsweise ist ein Sensierungsmittel vorgesehen, mit dessen Hilfe insbesondere beim Starten festgestellt wird, ob die Kraftstoffversorgungsleitung stromabwärts des Hochdruck-Speichers belüftet ist. Wird dies festgestellt, wird der Entlüftungsbetrieb beim Starten der Brennkraftmaschine durchgeführt. Wird dagegen keine Belüftung der Kraftstoffversorgungsleitung festgestellt, wird die Brennkraftmaschine vorzugsweise in einem normalen Aufstartbetrieb gestartet. Dabei wird in dem normalen Aufstartbetrieb vorzugsweise der Durchtrittsquerschnitt der Saugdrossel auf einen maximalen Wert eingestellt, um möglichst rasch einen vorherbestimmten Druck in dem Hochdruck-Speicher zu erreichen. Der Entlüftungsbetrieb unterscheidet sich demnach von dem normalen Aufstartbetrieb gerade dadurch, dass entgegen der herkömmlichen Vorgehensweise, bei der möglichst rasch durch Maximierung der Kraftstoffförderung ein vorherbestimmter Druck in dem Hochdruck-Speicher angestrebt wird, der Durchtrittsquerschnitt für den Kraftstoff im Bereich der Saugdrossel begrenzt wird, um den Kraftstoffstrom auf einen Wert zu beschränken, bei welchem das Mengenbegrenzungsventil nicht unzulässigerweise anspricht.A method is also preferred, which is characterized in that the venting operation is performed when starting the internal combustion engine. Preferably, the venting operation is performed at a first start of the internal combustion engine. Alternatively or additionally, it is provided that the venting operation is performed after a maintenance or repair of the internal combustion engine. In particular, the bleeding operation is performed when the fuel supply pipe is vented downstream of the high-pressure accumulator. Preferably, a Sensierungsmittel is provided with the help of which it is determined in particular when starting whether the fuel supply line is vented downstream of the high-pressure accumulator. If this is determined, the bleeding operation is performed when starting the internal combustion engine. On the other hand, if no ventilation of the fuel supply line is detected, the internal combustion engine is preferably started in a normal start-up operation. In this case, in the normal start-up operation preferably the passage cross-section of the suction throttle is set to a maximum value in order to achieve a predetermined pressure in the high-pressure accumulator as quickly as possible. The bleeding operation thus differs from the normal start-up operation precisely in that, contrary to the conventional approach, in which a predetermined pressure in the high-pressure accumulator is sought as quickly as possible by maximizing the fuel delivery, the passage cross-section for the fuel in the Suction throttle is limited in order to limit the fuel flow to a value at which the flow control valve does not respond inadmissible.

Es wird ein Verfahren bevorzugt, das sich dadurch auszeichnet, dass die Saugdrossel durch ein Motorsteuergerät der Brennkraftmaschine angesteuert wird. In dem Motorsteuergerät ist bevorzugt ein Algorithmus implementiert, mit dessen Hilfe der Druck in dem Hochdruck-Speicher im Normalbetrieb des Verbrennungsmotors steuer- und/oder regelbar ist, wobei der Durchtrittsquerschnitt der Saugdrossel bevorzugt bei einem normalen Aufstartbetrieb der Brennkraftmaschine maximiert wird, die Saugdrossel mithin ganz aufgesteuert wird, um den vorherbestimmten Druck möglichst rasch zu erreichen. In dem Motorsteuergerät ist weiterhin bevorzugt ein Algorithmus implementiert, der es ermöglicht, den Entlüftungsbetrieb durchzuführen, wobei in diesem der Durchtrittsquerschnitt der Saugdrossel kleiner oder gleich dem vorherbestimmten Grenzdurchtrittsquerschnitt eingestellt wird. Das Motorsteuergerät ist vorzugsweise mit der Saugdrossel zur Ansteuerung wirkverbunden.A method is preferred which is characterized in that the suction throttle is controlled by an engine control unit of the internal combustion engine. In the engine control unit, an algorithm is preferably implemented by means of which the pressure in the high-pressure accumulator can be controlled and / or regulated during normal operation of the internal combustion engine, wherein the passage cross section of the intake throttle is preferably maximized in a normal start-up operation of the internal combustion engine, the intake throttle thus completely is controlled in order to reach the predetermined pressure as quickly as possible. In the engine control unit, an algorithm is further preferably implemented, which makes it possible to carry out the venting operation, in which the passage cross section of the suction throttle is set smaller than or equal to the predetermined limit passage cross section. The engine control unit is preferably operatively connected to the suction throttle for driving.

Es wird auch ein Verfahren bevorzugt, das sich dadurch auszeichnet, dass der Entlüftungsbetrieb beendet wird, sobald die Kraftstoffversorgungsleitung entlüftet ist. Vorzugsweise wird der Entlüftungsbetrieb dadurch beendet, dass die Saugdrossel - bevorzugt von dem Motorsteuergerät - zur Regelung des Drucks in dem Hochdruck-Speicher angesteuert wird. Es wird also zum Beenden des Entlüftungsbetriebs die Ansteuerung der Saugdrossel geändert, wobei diese nicht mehr auf einem Durchtrittsquerschnitt kleiner oder gleich dem vorherbestimmten Grenzdurchtrittsquerschnitt gehalten wird, sondern indem diese derart angesteuert wird, dass eine Regelung des Drucks in dem Hochdruck-Speicher erfolgt. Nach gezielter Durchführung des Entlüftungsbetriebs wird demnach vorzugsweise auf einen normalen Betrieb der Brennkraftmaschine umgeschaltet. Das Ende des Entlüftungsbetriebs wird vorzugsweise durch das Sensierungsmittel erfasst, durch welches festgestellt werden kann, ob die Kraftstoffversorgungsleitung stromabwärts des Hochdruck-Speichers belüftet ist.A method is also preferred, which is characterized in that the bleeding operation is terminated as soon as the fuel supply line is vented. Preferably, the venting operation is terminated by the fact that the suction throttle - preferably by the engine control unit - is controlled to control the pressure in the high-pressure accumulator. It is thus changed to terminate the venting operation, the control of the suction throttle, which is no longer maintained on a passage cross-section less than or equal to the predetermined Grenzdurchtrittsquerschnitt, but by being controlled such that a regulation of the pressure takes place in the high-pressure accumulator. After targeted execution of the bleeding operation is therefore preferably switched to a normal operation of the internal combustion engine. The end of the bleeding operation is preferably detected by the sensing means by which it can be determined whether the fuel supply line is vented downstream of the high-pressure accumulator.

Es wird ein Verfahren bevorzugt, das sich dadurch auszeichnet, dass der vorherbestimmte Grenzdurchtrittsquerschnitt gewählt wird zu 50 %, vorzugsweise 25 %, vorzugsweise 15 %, vorzugsweise 10 %, vorzugsweise 5 %, vorzugsweise 2 %, vorzugsweise 1 % eines maximalen Durchtrittsquerschnitts der Saugdrossel. Die Saugdrossel ist dabei vorzugsweise so ausgebildet, dass ihr Durchtrittsquerschnitt zwischen einem minimalen Durchtrittsquerschnitt und einem maximalen Durchtrittsquerschnitt stufenweise oder bevorzugt kontinuierlich variabel ist. Durch entsprechende Wahl des Grenzdurchtrittsquerschnitts wird gewährleistet, dass im Entlüftungsbetrieb nur eine solche Menge Kraftstoff von der Hochdruckpumpe gefördert wird, bei der das Mengenbegrenzungsventil nicht unzulässig anspricht. Dabei ist es möglich, dass der vorherbestimmte und vorzugsweise in dem Motorsteuergerät hinterlegte Grenzdurchtrittsquerschnitt abhängig von einem in der Brennkraftmaschine eingesetzten Mengenbegrenzungsventil gewählt wird. Dieser Vorgehensweise liegt der Gedanke zugrunde, dass verschiedene Mengenbegrenzungsventile bei verschiedenen Werten eines über sie fließenden Kraftstoffstroms ansprechen, sodass bevorzugt der Grenzdurchtrittsquerschnitt auf ein konkret verbautes Mengenbegrenzungsventil abgestimmt wird. Insbesondere wird bevorzugt der vorherbestimmte Grenzdurchtrittsquerschnitt auf die konkret verwendete Saugdrossel und auf ein konkret verwendetes Mengenbegrenzungsventil abgestimmt, sodass gewährleistet ist, dass beim Entlüftungsbetrieb kein unzulässig hoher Volumenstrom über das Mengenbegrenzungsventil strömt, um dessen Ansprechen zu verhindern.A method is preferred which is characterized in that the predetermined limit passage cross section is selected to be 50%, preferably 25%, preferably 15%, preferably 10%, preferably 5%, preferably 2%, preferably 1% of a maximum passage cross section of the suction throttle. The Suction choke is preferably designed so that their passage cross-section between a minimum passage cross-section and a maximum passage cross-section is gradually or preferably continuously variable. By appropriate choice of the limit passage cross-section ensures that in the venting mode only such an amount of fuel is conveyed by the high-pressure pump, in which the flow control valve does not respond inadmissible. It is possible that the predetermined and preferably stored in the engine control unit limiting passage cross-section is selected depending on a used in the engine mass limiting valve. This procedure is based on the idea that different quantity-limiting valves respond at different values of a fuel flow flowing over them, so that preferably the limit passage cross-section is matched to a specifically installed quantity-limiting valve. In particular, the predetermined boundary passage cross-section is preferably matched to the specifically used suction throttle and a specifically used flow control valve, so that it is ensured that during the bleeding operation no unacceptably high flow rate flows through the flow control valve to prevent its response.

Es wird auch ein Verfahren bevorzugt, das sich dadurch auszeichnet, dass eine Motordrehzahl der Brennkraftmaschine während des Entlüftungsbetriebs bei ungefähr 100 Umdrehungen pro Minute (rounds per minute - rpm) gehalten wird. Dieser Wert liegt vorzugsweise unter einer Leerlaufdrehzahl der Brennkraftmaschine. Hierdurch wird die Fördermenge der Hochdruckpumpe zusätzlich reduziert, was für den Entlüftungsbetrieb vorteilhaft ist.A method is also preferred which is characterized in that an engine speed of the internal combustion engine during the bleeding operation at about 100 revolutions per minute (rpm) is maintained. This value is preferably below an idle speed of the internal combustion engine. As a result, the delivery rate of the high-pressure pump is additionally reduced, which is advantageous for the venting operation.

Es wird auch ein Verfahren bevorzugt, das sich dadurch auszeichnet, dass ein Druck stromabwärts des Mengenbegrenzungsventils erfasst wird. Hierzu ist bevorzugt ein Drucksensor stromabwärts des Mengenbegrenzungsventils in der Kraftstoffversorgungsleitung vorgesehen. Dieser ist vorzugsweise mit dem Motorsteuergerät wirkverbunden, sodass dieses den von dem Drucksensor erfassten Druck auswerten und zur Steuerung der Brennkraftmaschine heranziehen kann.A method is also preferred which is characterized in that a pressure is sensed downstream of the flow control valve. For this purpose, a pressure sensor is preferably provided downstream of the quantity limiting valve in the fuel supply line. This is preferably operatively connected to the engine control unit, so that it can evaluate the pressure detected by the pressure sensor and use to control the internal combustion engine.

Vorzugsweise wird anhand des erfassten Drucks - insbesondere in dem Motorsteuergerät - festgestellt, ob die Kraftstoffversorgungsleitung entlüftet ist. Es ist in diesem Fall mithilfe der von dem Drucksensor gelieferten Messwerte möglich, zu entscheiden, ob ein Entlüftungsbetrieb beim Starten der Brennkraftmaschine durchgeführt werden soll, beziehungsweise ob und wann der Entlüftungsbetrieb beendet werden soll.Preferably, it is determined on the basis of the detected pressure - in particular in the engine control unit - whether the fuel supply line is vented. In this case, it is possible to decide whether to use the readings provided by the pressure sensor Venting operation when starting the internal combustion engine to be performed, or if and when the venting operation should be terminated.

Es wird auch ein Verfahren bevorzugt, das sich dadurch auszeichnet, dass die Hochdruckpumpe von der Brennkraftmaschine mit der Motordrehzahl angetrieben wird. Die Hochdruckpumpe ist in diesem Fall direkt mit der Brennkraftmaschine derart wirkverbunden, dass sie in jedem Betriebszustand die gleiche Drehzahl wie diese aufweist. Gerade bei dieser Ausgestaltung ist es vorteilhaft, wenn der Druck in dem Hochdruck-Speicher mittels der Saugdrossel geregelt wird, weil die Förderleistung der Hochdruckpumpe abhängig von der Drehzahl der Brennkraftmaschine variiert.A method is also preferred, which is characterized in that the high-pressure pump is driven by the internal combustion engine at the engine speed. In this case, the high-pressure pump is operatively connected directly to the internal combustion engine in such a way that, in each operating state, it has the same rotational speed as the latter. Especially in this embodiment, it is advantageous if the pressure in the high pressure accumulator is controlled by means of the suction throttle, because the delivery rate of the high pressure pump varies depending on the speed of the internal combustion engine.

Die Aufgabe wird auch gelöst, indem eine Brennkraftmaschine mit den Merkmalen des Anspruchs 9 geschaffen wird. Diese umfasst ein Direkt-Einspritzungssystem, welches mindestens einen Injektor zur Einspritzung von Kraftstoff in eine Brennkammer der Brennkraftmaschine aufweist. Stromaufwärts des Injektors ist ein Hochdruck-Speicher vorgesehen, der zur Versorgung des Injektors mit Kraftstoff in Fluidverbindung mit dem Injektor steht. Ein Mengenbegrenzungsventil ist in der Fluidverbindung zwischen dem Hochdruck-Speicher und dem Injektor angeordnet, um eine von dem Motorspeicher zu dem Injektor strömende Kraftstoffmenge zu begrenzen. Eine Hochdruckpumpe ist zur Förderung von Kraftstoff in den Hochdruck-Speicher stromaufwärts desselben vorgesehen, wobei ein Druck in dem Hochdruck-Speicher stromaufwärts der Hochdruckpumpe durch eine Saugdrossel regelbar ist. Die Saugdrossel ist durch ein Motorsteuergerät der Brennkraftmaschine ansteuerbar. Die Brennkraftmaschine zeichnet sich dadurch aus, dass das Motorsteuergerät zur Entlüftung der Kraftstoffversorgungsleitung stromabwärts der Hochdruckpumpe die Saugdrossel während eines Entlüftungsbetriebs auf einen Durchtrittsquerschnitt für den Kraftstoff einstellt, der kleiner oder gleich als ein vorherbestimmter Grenzdurchtrittsquerschnitt ist. Der Grenzdurchtrittsquerschnitt wiederum ist kleiner als der maximale Durchtrittsquerschnitt der Saugdrossel, wobei der Durchtrittsquerschnitt der Saugdrossel im Entlüftungsbetrieb so gewählt ist, dass ein Kolben des Mengenbegrenzungsventils seine Sperrposition während des Entlüftens nicht erreicht. Hierdurch ergeben sich die Vorteile, die bereits in Zusammenhang mit dem Verfahren erläutert wurden.The object is also achieved by providing an internal combustion engine having the features of claim 9. This comprises a direct injection system which has at least one injector for injecting fuel into a combustion chamber of the internal combustion engine. Upstream of the injector, a high pressure accumulator is provided which is in fluid communication with the injector for supplying the injector with fuel. A quantity limiting valve is disposed in fluid communication between the high pressure accumulator and the injector to limit an amount of fuel flowing from the engine accumulator to the injector. A high pressure pump is provided for delivering fuel into the high pressure accumulator upstream thereof, and a pressure in the high pressure accumulator upstream of the high pressure pump is controllable by a suction throttle. The suction throttle can be controlled by an engine control unit of the internal combustion engine. The internal combustion engine is characterized in that the engine control unit for venting the fuel supply line downstream of the high-pressure pump adjusts the suction throttle during a bleeding operation to a passage cross-section for the fuel which is less than or equal to a predetermined limit passage cross-section. The boundary passage cross section in turn is smaller than the maximum passage cross section of the suction throttle, wherein the passage cross section of the suction throttle is selected in the bleeding mode so that a piston of the flow control valve does not reach its blocking position during venting. This results in the advantages that have already been explained in connection with the method.

Es ist möglich, dass die Saugdrossel bei einem Ausführungsbeispiel der Brennkraftmaschine in die Hochdruckpumpe integriert ist. Die Angabe, dass die Saugdrossel stromaufwärts der Hochdruckpumpe vorgesehen ist, bezieht sich insoweit insbesondere auf die funktionale Anordnung der Saugdrossel und bedeutet, dass die Saugdrossel den Zufluss von Kraftstoff zur Hochdruckpumpe begrenzt. Alternativ ist es auch möglich, dass die Saugdrossel als separates Element stromaufwärts der Hochdruckpumpe in der Kraftstoffversorgungsleitung angeordnet ist.It is possible that the suction throttle is integrated in one embodiment of the internal combustion engine in the high-pressure pump. The indication that the Saugdrossel is provided upstream of the high pressure pump, refers in so far in particular to the functional arrangement of the suction throttle and means that the suction throttle limits the flow of fuel to the high pressure pump. Alternatively, it is also possible that the suction throttle is arranged as a separate element upstream of the high-pressure pump in the fuel supply line.

Es wird auch eine Brennkraftmaschine bevorzugt, die sich dadurch auszeichnet, dass der mindestens eine Injektor einen internen Kraftstoffspeicher aufweist. Dieser ersetzt nicht den Hochdruck-Speicher, sondern ist zusätzlich zu diesem vorgesehen.An internal combustion engine is also preferred, which is characterized in that the at least one injector has an internal fuel reservoir. This does not replace the high-pressure reservoir, but is provided in addition to this.

Bei einem Ausführungsbeispiel der Brennkraftmaschine ist es auch möglich, dass das Mengenbegrenzungsventil in den Injektor integriert ist. Bei einem anderen Ausführungsbeispiel ist vorgesehen, dass das Mengenbegrenzungsventil als separates Element stromaufwärts des Injektors vorgesehen ist.In one embodiment of the internal combustion engine, it is also possible that the flow control valve is integrated into the injector. In another embodiment, it is provided that the quantity limiting valve is provided as a separate element upstream of the injector.

Die Beschreibung des Verfahrens einerseits und der Brennkraftmaschine andererseits sind komplementär zueinander zu verstehen. Insbesondere wird eine Brennkraftmaschine bevorzugt, die sich durch mindestens ein Merkmal auszeichnet, das durch mindestens einen Verfahrensschritt, vorzugsweise Kombinationen hiervon, einer Ausführungsform des Verfahrens bedingt ist. Umgekehrt wird ein Verfahren bevorzugt, das durch mindestens einen Verfahrensschritt gekennzeichnet ist, der sich aus mindestens einem Merkmal der Brennkraftmaschine, vorzugsweise Kombinationen hiervon, ergibt. Alle in Zusammenhang mit dem Verfahren beschriebenen Merkmale sind bevorzugt einzeln oder in Kombination miteinander Merkmale eines Ausführungsbeispiel der Brennkraftmaschine. Ebenso sind alle in Zusammenhang mit der Brennkraftmaschine beschriebenen Verfahrensschritte bevorzugt einzeln oder in Kombination miteinander Schritte einer Ausführungsform des Verfahrens.The description of the method on the one hand and the internal combustion engine on the other hand are to be understood as complementary to one another. In particular, an internal combustion engine is preferred which is characterized by at least one feature that is due to at least one method step, preferably combinations thereof, of an embodiment of the method. Conversely, a method is preferred which is characterized by at least one method step, which results from at least one feature of the internal combustion engine, preferably combinations thereof. All features described in connection with the method are preferably individually or in combination with each other features of an embodiment of the internal combustion engine. Likewise, all of the method steps described in connection with the internal combustion engine are preferably individually or in combination with one another steps of an embodiment of the method.

Die Erfindung wird im Folgenden anhand der Zeichnung näher erläutert. Dabei zeigt die einzige

Figur
eine schematische Darstellung eines Ausführungsbeispiels eines Direkt-Einspritzungssystems einer Brennkraftmaschine.
The invention will be explained in more detail below with reference to the drawing. The only one shows
figure
a schematic representation of an embodiment of a direct injection system of an internal combustion engine.

Die Figur zeigt eine schematische Darstellung eines Direkt-Einspritzungssystems 1 eines Ausführungsbeispiels einer Brennkraftmaschine. Das Direkteinspritzsystem 1 weist einen Injektor 3 auf, durch den mithilfe einer schematisch dargestellten Ventileinrichtung 5 Kraftstoff 7 in eine nicht dargestellte Brennkammer der Brennkraftmaschine einspritzbar ist. Bei dem dargestellten Ausführungsbeispiel umfasst der Injektor 3 außerdem einen internen Kraftstoffspeicher 9.The figure shows a schematic representation of a direct injection system 1 of an embodiment of an internal combustion engine. The direct injection system 1 has an injector 3 through which fuel 7 can be injected into a combustion chamber, not shown, of the internal combustion engine by means of a valve device 5 shown schematically. In the illustrated embodiment, the injector 3 also includes an internal fuel reservoir 9.

Eine Kraftstoffversorgungsleitung 11 dient zur Förderung von Kraftstoff aus einem Kraftstoffvorratsbehälter 13, vorzugsweise einem Tank, zu dem Injektor 3. Stromaufwärts des Injektors 3 ist ein Hochdruck-Speicher 15 angeordnet, aus dem der Injektor 3 mit Kraftstoff versorgt wird. Zwischen dem Hochdruck-Speicher 15 und dem Injektor 3 ist ein Mengenbegrenzungsventil 17 in der Kraftstoffversorgungsleitung 11 angeordnet, um die Brennkraftmaschine vor einer unzulässig hohen Kraftstoffmenge zu schützen, die über einen defekten Injektor 3 in die Brennkammer eingebracht werden könnte. Die Funktionsweise des Mengenbegrenzungsventils 17 wird im Folgenden noch näher erläutert.A fuel supply line 11 serves to convey fuel from a fuel tank 13, preferably a tank, to the injector 3. Upstream of the injector 3, a high-pressure accumulator 15 is arranged, from which the injector 3 is supplied with fuel. Between the high-pressure accumulator 15 and the injector 3, a quantity limiting valve 17 is arranged in the fuel supply line 11 in order to protect the internal combustion engine against an inadmissibly high amount of fuel which could be introduced into the combustion chamber via a defective injector 3. The operation of the quantity limiting valve 17 will be explained in more detail below.

Zur Förderung von Kraftstoff in den Hochdruck-Speicher 15 ist stromaufwärts desselben eine Hochdruckpumpe 19 in der Kraftstoffleitung 11 angeordnet. Deren Förderleistung wird durch eine stromaufwärts der Hochdruckpumpe 19 angeordnete Saugdrossel 21 gesteuert, wobei insbesondere der Druck in dem Hochdruck-Speicher 15 mittels der Saugdrossel 21 geregelt wird. Die Saugdrossel 21 ist hier schematisch als von der Hochdruckpumpe 19 separate Ventileinrichtung dargestellt. Es ist aber sehr wohl möglich, dass die Saugdrossel 21 als Teil der Hochdruckpumpe 19 ausgebildet beziehungsweise in diese integriert ist. Vorzugsweise ist ein Durchtrittsquerschnitt der Saugdrossel 21 zwischen einem minimalen Wert und einem maximalen Wert kontinuierlich variabel. Es ist möglich, dass der minimale Wert des Durchtrittsquerschnitts einer geschlossenen Stellung der Saugdrossel 21 entspricht, sodass in diesem Fall kein Kraftstoff über die Saugdrossel 21 förderbar ist.For conveying fuel into the high-pressure accumulator 15, a high-pressure pump 19 is arranged in the fuel line 11 upstream thereof. Their delivery rate is controlled by a suction throttle 21 arranged upstream of the high-pressure pump 19, wherein in particular the pressure in the high-pressure accumulator 15 is regulated by means of the suction throttle 21. The suction throttle 21 is shown here schematically as separate from the high-pressure pump 19 valve device. However, it is quite possible that the suction throttle 21 is formed as part of the high pressure pump 19 or integrated into it. Preferably, a passage cross-section of the suction throttle 21 is continuously variable between a minimum value and a maximum value. It is possible that the minimum value of the passage cross section corresponds to a closed position of the suction throttle 21, so that in this case no fuel can be conveyed via the suction throttle 21.

Bei dem dargestellten Ausführungsbeispiel ist stromaufwärts der Saugdrossel 21 eine Niederdruckpumpe 23 vorgesehen, die der Förderung von Kraftstoff aus dem Vorratsbehälter 13 über einen Filter 25 zu der Saugdrossel 21 dient.In the illustrated embodiment, upstream of the suction throttle 21, a low-pressure pump 23 is provided, which serves to convey fuel from the reservoir 13 via a filter 25 to the suction throttle 21.

Das Mengenbegrenzungsventil 17 weist bei dem dargestellten Ausführungsbeispiel eine Durchflussbegrenzungseinrichtung 27 und ein stromabwärts von dieser angeordnetes Ausgleichsvolumen 29 auf, wobei das Ausgleichsvolumen 29 vorzugsweise eine Drosseleinrichtung 31 umfasst. Die Durchflussbegrenzungseinrichtung 27 umfasst bei dem dargestellten Ausführungsbeispiel einen in einem Zylinder 33 verlagerbaren Kolben 35, der in der mit A gekennzeichneten Position durch ein Federelement 37 vorgespannt ist. Durch eine Festdrossel 39 ist schematisch angedeutet, dass im Bereich des Kolbens 35 ein vorherbestimmter Durchtrittsquerschnitt für Kraftstoff vorgesehen ist. Dabei ist es möglich, dass der Kraftstoff durch eine Bohrung in dem Kolben 35 - wie in der Figur durch die Festdrossel 39 angedeutet - hindurchströmen kann. Bei einem anderen Ausführungsbeispiel ist es möglich, dass der Kraftstoff seitlich an dem Kolben 35 vorbeiströmen kann. Auch andere Ausgestaltungen, die Funktion der Festdrossel 39 zu verwirklichen, sind möglich.In the exemplary embodiment illustrated, the quantity limiting valve 17 has a flow-limiting device 27 and a compensating volume 29 arranged downstream of it, wherein the compensating volume 29 preferably comprises a throttle device 31. The flow-limiting device 27 comprises in the illustrated embodiment a displaceable in a cylinder 33 piston 35 which is biased in the position indicated by A by a spring element 37. By a fixed throttle 39 is schematically indicated that in the region of the piston 35, a predetermined passage cross-section is provided for fuel. It is possible that the fuel through a bore in the piston 35 - as indicated in the figure by the fixed throttle 39 - can flow through. In another embodiment, it is possible that the fuel may flow past the piston 35 laterally. Other embodiments, the function of the fixed throttle 39 to realize, are possible.

Der Kolben 35 ist von seiner bei A dargestellten Anschlagsposition über eine bei B dargestellte, mittlere Position entgegen der Vorspannkraft des Federelements 37 bis zu einer bei C dargestellten Anschlagsposition verlagerbar.The piston 35 is displaceable from its stop position shown at A via a middle position shown at B against the biasing force of the spring element 37 to a stop position shown at C.

In der Anschlagsposition C ist kein Kraftstofffluss über die Festdrossel 39 mehr möglich. Das Mengenbegrenzungsventil 17 ist in diesem Fall in einer Sperrstellung angeordnet, sodass kein Kraftstoff mehr von dem Hochdruck-Speicher 15 zu dem Injektor 3 strömen kann.In the stop position C no fuel flow through the fixed throttle 39 is more possible. The quantity limiting valve 17 is arranged in a blocking position in this case, so that no more fuel can flow from the high-pressure accumulator 15 to the injector 3.

Während eines normalen Betriebs der Brennkraftmaschine ist die Kraftstoffversorgungsleitung 11 vollständig mit im Wesentlichen inkompressiblem Kraftstoff gefüllt. Der Druck in dem Hochdruck-Speicher 15 wird mittels der Saugdrossel 21 geregelt. Ist die Ventileinrichtung 5 des Injektors 3 geschlossen, fließt kein Kraftstoff von dem Hochdruck-Speicher 15 über das Mengenbegrenzungsventil 17 zu dem Injektor 3. Wird mittels des Injektors 3 eine Einspritzung von Kraftstoff 7 in die dem Injektor 3 zugeordnete Brennkammer durchgeführt, fließt Kraftstoff 7 über die Ventileinrichtung 5 ab, wodurch sich zugleich eine Kraftstoffströmung von dem Hochdruck-Speicher 15 zu dem Injektor 3 über das Mengenbegrenzungsventil 17 ergibt. Wird dabei pro Zeiteinheit mehr Kraftstoff 7 über die Ventileinrichtung 5 abgegeben, als durch die Festdrossel 39 nachströmen kann, wird dies ausgeglichen, indem das Ausgleichsvolumen 29 reduziert wird, wobei sich der Kolben 35 - in der Figur - nach rechts entgegen der Vorspannkraft des Federelements 37 verlagert. Die Einspritzung endet im Normalbetrieb typischerweise, wenn der Kolben 35 ungefähr seine bei B dargestellte Position erreicht. Da zu diesem Zeitpunkt die Ventileinrichtung 5 schließt, mithin keine weitere Kraftstoffinjektion mehr stattfindet, erfolgt nun eine Ausgleichsströmung von dem Hochdruck-Speicher 15 über die Festdrossel 39 in den internen Speicher 9, weil der Druck stromabwärts der Festdrossel 39 während des Einspritzereignisses und während der Verlagerung des Kolbens 35 im Vergleich zu dem Druckniveau des Hochdruck-Speichers 15 abgenommen hat. Während des Druckausgleichs verlagert sich der Kolben 35 zurück aus der Position B in die Position A, in die er durch das Federelement 37 gedrängt wird.During normal operation of the internal combustion engine, the fuel supply line 11 is completely filled with substantially incompressible fuel. The pressure in the high-pressure accumulator 15 is regulated by means of the suction throttle 21. If the valve device 5 of the injector 3 is closed, no fuel flows from the high-pressure accumulator 15 via the quantity limiting valve 17 to the injector 3. If an injection of fuel 7 into the combustion chamber assigned to the injector 3 is carried out by means of the injector 3, fuel 7 flows over the valve device 5 from, whereby at the same time results in a fuel flow from the high-pressure accumulator 15 to the injector 3 via the flow control valve 17. If more fuel 7 is delivered via the valve device 5 per unit time than can flow through the fixed throttle 39, this is compensated for by reducing the compensating volume 29, wherein the piston 35 - in the figure - to the right against the biasing force displaced the spring element 37. In normal operation, the injection typically ends when the piston 35 reaches its approximate position at B. Since at this time the valve device 5 closes, so that no further fuel injection takes place, a compensation flow now takes place from the high-pressure accumulator 15 via the fixed throttle 39 into the internal accumulator 9, because the pressure downstream of the fixed throttle 39 during the injection event and during the relocation of the piston 35 has decreased compared to the pressure level of the high-pressure accumulator 15. During pressure equalization, the piston 35 shifts back from the position B to the position A, in which it is urged by the spring element 37.

Wird aufgrund einer Fehlfunktion des Injektors 3 die Ventileinrichtung 5 nicht oder nicht rechtzeitig geschlossen, fällt der Druck in dem internen Speicher 9 beziehungsweise in der Kraftstoffversorgungsleitung 11 stromabwärts des Mengenbegrenzungsventils 17 weiter ab, und das Ausgleichsvolumen 29 wird weiter verringert, indem sich der Kolben 35 über die Position B hinaus - in der Figur - nach rechts verlagert. Durch die Festdrossel 39 kann nämlich nicht genug Kraftstoff pro Zeiteinheit nachfließen, um den Kraftstoffabfluss über die Ventileinrichtung 5 auszugleichen. Dauert die Einspritzung an, erreicht der Kolben 35 schließlich die bei C dargestellte Position, in der die Fluidverbindung zwischen dem Hochdruck-Speicher 15 und dem Injektor 3 gesperrt ist. Es kann dann kein Kraftstoff mehr von dem Hochdruck-Speicher 15 nachfließen, sodass das Ausgleichsvolumen 29, gegebenenfalls der interne Speicher 9 und der Injektor 3 in die Brennkammer leerläuft. Hierdurch sinkt der Druck im Bereich des Injektors 3 ab, sodass der Kolben 35 dauerhaft durch die Druckdifferenz zwischen dem Hochdruck-Speicher 15 einerseits und dem Injektor 3 andererseits in der bei C dargestellten Sperrposition gehalten wird. Das Mengenbegrenzungsventil 17 ist daher dauerhaft gesperrt, und es kann keine unzulässige Kraftstoffmenge über den defekten Injektor 3 in die Brennkammer eingebracht werden. Hierdurch wird die Brennkraftmaschine vor Beschädigungen durch eine zu große Energiemenge geschützt.If due to a malfunction of the injector 3, the valve device 5 is not or not closed in time, the pressure in the internal memory 9 or in the fuel supply line 11 downstream of the flow control valve 17 continues to fall, and the compensation volume 29 is further reduced by the piston 35 on the position B out - in the figure - shifted to the right. Because of the fixed throttle 39, in fact not enough fuel per unit of time can flow in order to compensate for the fuel outflow via the valve device 5. When the injection lasts, the piston 35 finally reaches the position shown at C in which the fluid communication between the high-pressure accumulator 15 and the injector 3 is blocked. It can then no longer flow of fuel from the high-pressure accumulator 15, so that the compensating volume 29, possibly the internal memory 9 and the injector 3 idles into the combustion chamber. As a result, the pressure drops in the region of the injector 3, so that the piston 35 is permanently held by the pressure difference between the high-pressure accumulator 15 on the one hand and the injector 3 on the other hand in the blocking position shown at C. The quantity limiting valve 17 is therefore permanently locked, and it can not be introduced inadmissible amount of fuel through the defective injector 3 in the combustion chamber. As a result, the internal combustion engine is protected from damage caused by an excessive amount of energy.

Ist bei einem Erststart der Brennkraftmaschine oder nach einer Wartung oder Reparatur die Kraftstoffversorgungsleitung 11 insgesamt oder jedenfalls stromabwärts des Mengenbegrenzungsventils 17 belüftet, ergibt sich folgendes Problem: Bei einem Start der Brennkraftmaschine fördert die Hochdruckpumpe 19 Kraftstoff in den Hochdruck-Speicher 15 und von diesem weiter über die Festdrossel 39 in das Ausgleichsvolumen 29 und zu dem Injektor 3. Typischerweise ist der Durchtrittsquerschnitt der Saugdrossel 21 bei einem normalen Aufstartbetrieb der Brennkraftmaschine auf ein Maximum eingestellt, damit sich ein vorherbestimmter Druck in dem Hochdruck-Speicher 15 möglichst rasch einstellt. Da die Festdrossel 39 ein Strömungshindernis darstellt, fällt über dem Kolben 35 ein Druck ab. Ist nun das Ausgleichsvolumen 29 belüftet, also mit einem kompressiblen Medium, insbesondere Luft, gefüllt, bewegt sich der Kolben 35 aufgrund des Druckunterschieds rasch entgegen der Vorspannkraft des Federelements 37 - in der Figur - nach rechts, wobei das über die Festdrossel 39 pro Zeiteinheit nachströmende Kraftstoffvolumen nicht ausreicht, um die Kompression in dem Ausgleichsvolumen 29 auszugleichen. Daher besteht die Gefahr, dass der Kolben 35 die bei C dargestellte Position erreicht, wodurch das Mengenbegrenzungsventil 17 anspricht und die Fluidverbindung zwischen dem Hochdruck-Speicher 15 und dem Injektor 3 dauerhaft sperrt. Es ist dann keine Einspritzung mehr durch den Injektor 3 möglich. Dies führt zu einem Leistungsmangel und/oder zu einem unrunden Motorlauf der Brennkraftmaschine. Die Brennkraftmaschine muss dann unter Umständen mehrfach komplett heruntergefahren werden, und die Kraftstoffversorgungsleitung 11 muss stromaufwärts des Mengenbegrenzungsventils 17 entspannt werden, weil anders keine Rückverlagerung des Kolbens 35 in die Position A erreichbar ist.If at a first start of the internal combustion engine or after maintenance or repair the fuel supply line 11 ventilated all or at least downstream of the flow control valve 17, the following problem arises: At a start of the internal combustion engine promotes the high-pressure pump 19 fuel in the high-pressure accumulator 15 and from this on the fixed throttle 39 in the compensating volume 29 and to the injector 3. Typically, the passage cross section of the suction throttle 21st set at a normal start-up operation of the internal combustion engine to a maximum, so that a predetermined pressure in the high-pressure accumulator 15 sets as soon as possible. Since the fixed throttle 39 is a flow obstacle, above the piston 35, a pressure drops. Now, if the compensating volume 29 is vented, so filled with a compressible medium, in particular air, the piston 35 moves due to the pressure difference rapidly against the biasing force of the spring element 37 - in the figure - to the right, the flowing over the fixed throttle 39 per unit time Fuel volume is insufficient to compensate for the compression in the compensation volume 29. Therefore, there is a risk that the piston 35 reaches the position shown at C, whereby the flow control valve 17 responds and permanently blocks the fluid communication between the high pressure accumulator 15 and the injector 3. It is then no longer possible injection through the injector 3. This leads to a lack of power and / or to a non-circular engine running of the internal combustion engine. The internal combustion engine may then have to be shut down completely several times, and the fuel supply line 11 must be expanded upstream of the flow control valve 17, because otherwise no return displacement of the piston 35 in the position A can be achieved.

Mithilfe des erfindungsgemäßen Verfahrens und der erfindungsgemäßen Brennkraftmaschine wird diese problematische Situation vermieden. In einem Entlüftungsbetrieb wird die Saugdrossel 21 so angesteuert, dass sie lediglich einen Durchtrittsquerschnitt aufweist, der kleiner oder gleich einem vorherbestimmten Grenzdurchtrittsquerschnitt ist. Der Grenzdurchtrittsquerschnitt ist dabei vorzugsweise kleiner als ein im Normalbetrieb der Brennkraftmaschine typischerweise von der Saugdrossel 21 angenommener Durchtrittsquerschnitt, und insbesondere kleiner, vorzugsweise sehr viel kleiner, als der maximale Durchtrittsquerschnitt, der bei einem normalen Aufstarten der Brennkraftmaschine eingenommen wird. Auf diese Weise wird die von der Hochdruckpumpe 19 geförderte Kraftstoffmenge begrenzt, sodass die Kraftstoffversorgungsleitung 11 stromaufwärts der Hochdruckpumpe 19 langsam mit Kraftstoff gefüllt wird.With the aid of the method according to the invention and the internal combustion engine according to the invention, this problematic situation is avoided. In a venting operation, the suction throttle 21 is controlled so that it only has a passage cross-section which is smaller than or equal to a predetermined limit passage cross-section. The limit passage cross-section is preferably smaller than a passage cross-section typically assumed by the suction throttle 21 during normal operation of the internal combustion engine, and in particular smaller, preferably much smaller, than the maximum passage cross-section occupied by a normal starting of the internal combustion engine. In this way, the amount of fuel delivered by the high-pressure pump 19 is limited so that the fuel supply line 11 upstream of the high-pressure pump 19 is slowly filled with fuel.

Besonders bevorzugt wird der Durchtrittsquerschnitt der Saugdrossel 21 im Entlüftungsbetrieb so eingestellt, dass die von der Hochdruckpumpe 19 geförderte Kraftstoffmenge bis zum Ende des Entlüftungsbetriebs gerade dem Volumenstrom entspricht, der durch die Festdrossel 39 strömt.Particularly preferably, the passage cross section of the suction throttle 21 is set in the venting operation so that the amount of fuel delivered by the high pressure pump 19 until the end of the bleeding mode just corresponds to the flow rate flowing through the fixed throttle 39.

Bei einer anderen Ausführungsform des Verfahrens wird der Durchtrittsquerschnitt der Saugdrossel 21 im Entlüftungsbetrieb vorzugsweise so gewählt, dass sich der Kolben 35 nicht, nur sehr langsam, oder höchstens nur so rasch in Richtung seiner in C dargestellten Anschlagsposition bewegt, dass die Entlüftung der Kraftstoffversorgungsleitung 11 abgeschlossen ist, bevor der Kolben 35 seine Sperrposition erreicht. Auf diese Weise wird sichergestellt, dass der Kolben 35 seine Sperrposition während des Entlüftens nicht erreicht. Ist die Entlüftung abgeschlossen, gleichen sich über die Festdrossel 39 der Druck in dem Hochdruck-Speicher 15 und der Druck stromabwärts des Mengenbegrenzungsventils 17, insbesondere in dem internen Kraftstoffspeicher 9, aus. Der Kolben 35 bewegt sich angetrieben durch die Rückstellkraft des Federelements 37 zurück in seine in A dargestellte Position. Ein Normalbetrieb der Brennkraftmaschine ist dann möglich, insbesondere kann dann der Druck in dem Hochdruck-Speicher 15 über die Saugdrossel 21 geregelt werden.In another embodiment of the method, the passage cross section of the suction throttle 21 in the venting operation is preferably selected so that the piston 35 does not move, only very slowly, or at most only as quickly in the direction of its stop position shown in C that the venting of the fuel supply line 11 is completed is before the piston 35 reaches its locking position. In this way it is ensured that the piston 35 does not reach its locking position during venting. Once the venting has been completed, the pressure in the high-pressure accumulator 15 and the pressure downstream of the quantity-limiting valve 17, in particular in the internal fuel accumulator 9, are equalized via the fixed throttle 39. The piston 35 moves driven by the restoring force of the spring member 37 back to its position shown in A. A normal operation of the internal combustion engine is then possible, in particular then the pressure in the high-pressure accumulator 15 can be regulated via the suction throttle 21.

Die Drehzahl der Brennkraftmaschine wird vorzugsweise während des Entlüftungsbetriebs bei ungefähr 100 rpm gehalten. Nach Beendigung des Entlüftungsbetriebs wird sie vorzugsweise auf eine Leerlaufdrehzahl erhöht, die beispielsweise bei ungefähr 350 rpm liegt. Indem die Hochdruckpumpe 19 vorzugsweise mit der Drehzahl der Brennkraftmaschine angetrieben wird, wobei diese bevorzugt während des Entlüftungsbetriebs reduziert ist, wird über die Ansteuerung der Saugdrossel 21 hinaus die Förderleistung der Hochdruckpumpe 19 begrenzt, was den Entlüftungsbetrieb besonders sicher macht.The speed of the internal combustion engine is preferably maintained at approximately 100 rpm during the bleeding operation. Upon completion of the bleed operation, it is preferably increased to an idle speed that is, for example, about 350 rpm. By the high-pressure pump 19 is preferably driven by the speed of the internal combustion engine, which is preferably reduced during the bleeding operation, the delivery of the high-pressure pump 19 is limited beyond the control of the suction throttle 21, which makes the bleeding operation particularly safe.

Insgesamt zeigt sich, dass es mithilfe des Verfahrens und der Brennkraftmaschine möglich ist, ein unerwünschtes Ansprechen des Mengenbegrenzungsventils 17 beim Entlüften der Kraftstoffversorgungsleitung 11 zu vermeiden.Overall, it is found that it is possible by means of the method and the internal combustion engine, to avoid an undesirable response of the flow control valve 17 when venting the fuel supply line 11.

Claims (10)

  1. Method for venting a fuel supply line (11) of a direct-injection internal combustion engine, wherein the fuel supply line (11) has an injector (3), a high-pressure accumulator (15) upstream of the injector (3), a flow rate limiting valve (17) between the high-pressure accumulator (15) and the injector (3) for the purposes of limiting a fuel flow rate passing from the high-pressure accumulator (15) to the injector (3), and a high-pressure pump (19) upstream of the high-pressure accumulator (15) for delivering fuel into the high-pressure accumulator (15), wherein a pressure in the high-pressure accumulator (15) is regulated by means of an intake throttle (21) arranged upstream of the high-pressure pump (19), characterized in that the fuel supply line (11) is vented downstream of the high-pressure pump (19) by virtue of the fact that, during a venting operating mode, a passage cross section for the fuel which is smaller than or equal to a predetermined threshold passage cross section is set in the intake throttle (21), wherein the threshold passage cross section is set to a smaller value than the maximum passage cross section of the intake throttle (21), and wherein the passage cross section of the intake throttle (21) in the venting operating mode is selected such that a piston (35) of the flow rate limiting valve (17) does not reach its blocking position during the venting.
  2. Method according to Claim 1, characterized in that the venting operating mode is implemented upon starting of the internal combustion engine, in particular upon an initial start or after maintenance or repair of the internal combustion engine, in particular if the fuel supply line (11) has been aerated downstream of the high-pressure accumulator (15).
  3. Method according to one of the preceding claims, characterized in that the intake throttle (21) is actuated by an engine control unit of the internal combustion engine.
  4. Method according to one of the preceding claims, characterized in that the venting operating mode is ended when the fuel supply line (11) has been vented, wherein the venting operating mode is preferably ended by virtue of the intake throttle (21) being actuated for the purposes of regulating the pressure in the high-pressure accumulator (15).
  5. Method according to one of the preceding claims, characterized in that the predetermined threshold passage cross section is selected to be 50%, preferably 25%, preferably 15%, preferably 10%, preferably 5%, preferably 2%, preferably 1% of the maximum passage cross section of the intake throttle (21).
  6. Method according to one of the preceding claims, characterized in that an engine speed of the internal combustion engine is kept at approximately 100 rpm during the venting operating mode.
  7. Method according to one of the preceding claims, characterized in that a pressure downstream of the flow rate limiting valve (17) is detected, wherein determination of whether the fuel supply line (11) has been vented is performed preferably on the basis of the detected pressure.
  8. Method according to one of the preceding claims, characterized in that the high-pressure pump (19) is driven at the engine speed by the internal combustion engine.
  9. Internal combustion engine having a direct-injection system (1) which has at least one injector (3) for injecting fuel into a combustion chamber of the internal combustion engine, wherein, upstream of the injector (3), there is provided a high-pressure accumulator (15) which is fluidically connected to the injector (3) for the purposes of supplying fuel to the injector (3), wherein a flow rate limiting valve (17) is arranged in the fluidic connection between the high-pressure accumulator (15) and the injector (3) for the purposes of limiting a fuel flow rate passing from the high-pressure accumulator (15) to the injector (3), and wherein a high-pressure pump (19) for delivering fuel into the high-pressure accumulator (15) is provided upstream of the latter, wherein, for regulating a pressure in the high-pressure accumulator (15), an intake throttle (21) is provided upstream of the high-pressure pump (19), which intake throttle can be actuated by an engine control unit of the internal combustion engine, characterized in that, for the venting of the fuel supply line (11) downstream of the high-pressure pump (19), the engine control unit sets the intake throttle (21), during a venting operating mode, to a passage cross section for the fuel which is smaller than or equal to a predetermined threshold passage cross section, wherein the threshold passage cross section is smaller than the maximum passage cross section of the intake throttle (21), and wherein the passage cross section of the intake throttle (21) in the venting operating mode is selected such that a piston (35) of the flow rate limiting valve (17) does not reach its blocking position during the venting.
  10. Internal combustion engine according to Claim 9, characterized in that the at least one injector (3) has an internal fuel accumulator.
EP14708482.6A 2013-03-11 2014-03-05 Method for venting a fuel supply line, and internal combustion engine Active EP2971746B1 (en)

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PCT/EP2014/000556 WO2014139643A1 (en) 2013-03-11 2014-03-05 Method for venting a fuel supply line, and internal combustion engine

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CN107489571B (en) * 2017-08-04 2020-01-10 河北华北柴油机有限责任公司 Automatic exhaust method of electric control monoblock pump
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RU2037068C1 (en) * 1991-06-03 1995-06-09 Акционерное общество "Ковровский экскаваторный завод" Fuel system for diesel
DE10057786A1 (en) * 2000-11-22 2002-06-06 Siemens Ag Injection system for an internal combustion engine and method for regulating and / or venting such an injection system
DE10117401C2 (en) * 2001-04-06 2003-02-27 Mtu Friedrichshafen Gmbh Fuel injection system for an internal combustion engine
DE10157135B4 (en) * 2001-11-21 2004-03-11 Man B & W Diesel Ag Fuel supply system in the form of a common rail system of an internal combustion engine with several cylinders
DE10342116B4 (en) * 2003-09-10 2005-08-11 Adam Opel Ag Bleed a fuel supply line
DE102005012165B4 (en) * 2005-03-17 2007-02-08 L'orange Gmbh Fuel accumulator of a fuel injection system for multi-cylinder internal combustion engine and flow control valve for such
DE102005025114A1 (en) * 2005-06-01 2006-12-07 Robert Bosch Gmbh Fuel conveyor device for e.g. internal combustion engine has control cross-section, which has aperture angle area wise, which is smaller in first adjustment range than in second adjustment range
DE102007029808A1 (en) * 2007-06-27 2009-01-08 Dr. Ing. H.C. F. Porsche Aktiengesellschaft A method of venting a fuel injection line of a direct injection internal combustion engine

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* Cited by examiner, † Cited by third party
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DE102013204093A1 (en) 2014-09-11
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HK1219525A1 (en) 2017-04-07
EP2971746A1 (en) 2016-01-20
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DE102013204093B4 (en) 2021-03-18
RU2015142846A (en) 2017-04-18
US20150377199A1 (en) 2015-12-31
WO2014139643A1 (en) 2014-09-18
KR102127935B1 (en) 2020-06-29

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