EP2890888A1 - Low-pressure circuit for a fuel injection system, fuel injection system and method for operating a fuel injection system - Google Patents

Low-pressure circuit for a fuel injection system, fuel injection system and method for operating a fuel injection system

Info

Publication number
EP2890888A1
EP2890888A1 EP13727584.8A EP13727584A EP2890888A1 EP 2890888 A1 EP2890888 A1 EP 2890888A1 EP 13727584 A EP13727584 A EP 13727584A EP 2890888 A1 EP2890888 A1 EP 2890888A1
Authority
EP
European Patent Office
Prior art keywords
fuel
pressure
injection system
low
fuel injection
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP13727584.8A
Other languages
German (de)
French (fr)
Inventor
Francesco Lucarelli
Thomas Koenig
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.)
Robert Bosch GmbH
Original Assignee
Robert Bosch 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 Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP2890888A1 publication Critical patent/EP2890888A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
    • F02M63/02—Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively
    • F02M63/0225—Fuel-injection apparatus having a common rail feeding several injectors ; Means for varying pressure in common rails; Pumps feeding common rails
    • F02M63/0265—Pumps feeding common rails
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
    • F02M63/0001—Fuel-injection apparatus with specially arranged lubricating system, e.g. by fuel oil
    • 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
    • F02M37/0047—Layout or arrangement of systems for feeding fuel
    • F02M37/0052—Details on the fuel return circuit; Arrangement of pressure regulators
    • 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
    • F02M59/00—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps
    • F02M59/02—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type
    • F02M59/10—Pumps specially adapted for fuel-injection and not provided for in groups F02M39/00 -F02M57/00, e.g. rotary cylinder-block type of pumps of reciprocating-piston or reciprocating-cylinder type characterised by the piston-drive
    • F02M59/102—Mechanical drive, e.g. tappets or cams
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
    • F02M63/02—Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively
    • F02M63/0225—Fuel-injection apparatus having a common rail feeding several injectors ; Means for varying pressure in common rails; Pumps feeding common rails
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
    • F02M63/02—Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively
    • F02M63/0225—Fuel-injection apparatus having a common rail feeding several injectors ; Means for varying pressure in common rails; Pumps feeding common rails
    • F02M63/0275—Arrangement of common rails

Definitions

  • the invention relates to a low-pressure circuit for a fuel injection system having the features of the preamble of claim 1. Furthermore, the invention relates to a fuel injection system with such a low-pressure circuit and a method for operating a fuel injection system.
  • DE 10 2006 018 702 A1 discloses a high-pressure fuel delivery device for an internal combustion engine, which comprises a high-pressure pump and a low-pressure flow path.
  • the low-pressure flow path leads from a fuel inlet of the high-pressure fuel delivery device to a receiving space for a drive shaft of the high-pressure pump and further to at least one inlet valve of the high-pressure pump.
  • a return flow path for returning leakage and / or lubricating fuel is provided, which is connected via shaft bearings for rotatably supporting the drive shaft with the receiving space of the high-pressure pump.
  • the return flow path opens into the low-pressure flow path, wherein in the return flow path at least one throttle for the targeted adjustment of the amount of fuel returned can be arranged.
  • the efficiency of the high-pressure fuel conveyor is to be improved.
  • the cooling amount can not be increased to the required extent via the throttle.
  • the result may be a deterioration of the fuel lubricity and / or an increased risk of wear.
  • the lubricating film between a roller of a plunger assembly and a support member for rotatably supporting the roller to a critical degree decrease, so that it comes to premature wear of the plunger assembly and thus to the failure of the conveyor.
  • the present invention is therefore an object of the invention to provide a low-pressure circuit for a fuel injection system or a fuel injection system with at least one arranged in a return throttle, which allows a simple adjustment of the amount of fuel returned and at the same time does not have the disadvantages mentioned above. Furthermore, a method for operating such a fuel injection system is to be specified.
  • the proposed low-pressure circuit for a fuel injection system comprises a fuel tank and a prefeed pump, by means of which fuel can be sucked in from the fuel tank and via a fuel line to an engine room of a high-pressure pump.
  • the engine room is connected via shaft bearings with a return line.
  • at least two throttles are also provided for connecting the engine room to the return, which are each connected in parallel to the shaft bearings and / or switchable via a valve. While a basic leakage for cooling and / or lubrication of the high-pressure pump is ensured via the shaft bearings, the adjustment of the required leakage quantity takes place via the parallel-connected or switchable throttles of the low-pressure circuit according to the invention.
  • a valve is provided, via which at least one throttle is switched on or off, so that another, the engine room with the return connecting, the shaft bearing bypassing flow path is releasable or closable.
  • This presupposes that at least one throttle-without an upstream valve-forms a first flow path connecting the engine room with the return, bypassing the shaft bearing, which ensures the required amount of leakage during normal operation of the high-pressure pump.
  • an increase in the leakage quantity and in this way improved cooling and / or lubrication of the high-pressure pump can be achieved via the at least one additional switchable throttle, which is dependent on the throttle cross-section and the respective prevailing pressure.
  • the throttle cross-section should preferably be selected such that on the one hand a significant improvement in the cooling and / or the
  • Lubrication of the high pressure pump is achieved, on the other hand, the mass balance of the low pressure circuit is not violated. Accordingly, the maximum amount provided by the prefeed pump must not be exceeded.
  • the advantage of the invention is to be seen in particular in that an increase in the amount of leakage occurs only when necessary, especially at a short-term, very high load on the high-pressure pump. For example, in critical operating situations, the pressure and / or the temperature in the engine room of the high pressure pump may rise above a predetermined limit, so that the provision of an additional cooling and / or lubricating amount is required.
  • At least two throttles are provided, of which at least one throttle is connected via a valve to the engine room of the high-pressure pump and consequently can be switched on or off.
  • the valve is a check valve. It is therefore a passively operable valve that opens when exceeding a predetermined opening pressure. Such valves are particularly simple and inexpensive to produce, so that the production cost of a low pressure circuit according to the invention are hardly increased.
  • the designed as a check valve valve opens when a certain limit pressure is exceeded in the engine room of the high pressure pump.
  • the opening pressure of the valve is selected such that it is below the maximum allowable pressure in the engine room of the high-pressure pump.
  • the opening pressure may be 1 bar below the maximum allowable pressure in the engine room.
  • valve can also be designed as an actively operable valve, which is connected to a control unit.
  • the control unit is furthermore preferably connected to at least one sensor for detecting a pressure and / or a temperature in the low-pressure circuit, so that when a preset limit value is exceeded, the valve is opened.
  • the prefeed pump is preferably a regulated electric fuel pump.
  • a regulated electric fuel pump By using a regulated electric fuel pump as prefeed pump, the use of a metering unit and / or an overflow valve is dispensable. Since concepts with overflow regularly, especially at a given interior pressure and steep curve of the spill valve, have the disadvantage that large leakage quantities must be returned, the omission of the spill valve is basically welcome.
  • at least one fuel filter is arranged between the prefeed pump and the high-pressure pump. The fuel filter protects the high-pressure pump from harmful particles contained in the fuel.
  • At least one sensor preferably a pressure and / or temperature sensor, for detecting the fuel pressure and / or the fuel temperature in the low-pressure circuit, in particular in the fuel line and / or in the engine room of the high-pressure pump, may be arranged between the prefeed pump and the high-pressure pump 5 ,
  • the values detected by means of the sensor can be used to control a prefeed pump designed as an electric fuel pump and / or to actuate a valve, via which at least one throttle arranged in a return can be connected or disconnected.
  • the fuel line is connected via the engine room with an inlet of the high-pressure pump. This means that the entire conveyed via the feed pump fuel flow first passes into the engine room of the high pressure pump and fed from there as a flow to the inlet of the high pressure pump or as the cooling and / or lubrication of the high pressure pump serving leakage flow through the shaft bearings and the parallel connected or switchable chokes is removed.
  • the further proposed for the solution of the above-mentioned object fuel injection system for injecting fuel into the combustion chamber of an internal combustion engine has a low pressure circuit according to the invention.
  • the proposed fuel injection system is therefore characterized by an improved degree of efficiency and a reduction in C0 2 emissions.
  • the stress on the high-pressure pump decreases because impermissibly high pressure and / or temperature increases in the engine room of the high-pressure pump are prevented. This increases the life of the high-pressure pump.
  • the cow's Ventilation and / or lubrication of the high-pressure pump serving leakage amount can therefore be increased via a switchable throttle, so that an impermissibly high pressure or an impermissibly high temperature in the engine room of the high-pressure pump can be effectively avoided. Accordingly, in critical operating situations, the cooling and / or lubrication of the high-pressure pump can be improved, so that damage to the high-pressure pump is counteracted.
  • the schematically illustrated low-pressure circuit comprises a prefeed pump 2 designed as a controllable electric fuel pump, by means of which fuel can be supplied from a fuel tank 1 via a fuel line 3 to a high-pressure pump 5.
  • the fuel line 3 discharges into an engine room 4 of the high pressure pump 5, in which the amount of fuel supplied is divided into a flow rate and a cooling and / or lubricating amount.
  • the delivery rate is fed via an inlet 14 to a high-pressure area (not shown) of the high-pressure pump 5, while the amount of coolant and / or lubricant passes back into the fuel tank 1 via a return line 8.
  • the return 8 is connected to the engine room 4 via shaft bearings 6, 7 of the high-pressure pump 5.
  • a parallel to the shaft bearings 6, 7 connected throttle 9 is provided, which connects the return 8 with the engine room 4 of the high-pressure pump 5.
  • the shaft bearings 6, 7 and the parallel-connected throttle 9 ensure a minimum amount of cooling or minimum amount of lubricant.
  • the low-pressure circuit according to the invention shown schematically in the figure has a further throttle 10, which is also connected via a valve 11 parallel to the shaft bearings 6, 7 switchable.
  • the valve 11 is presently designed as a simple check valve whose opening pressure is below the maximum allowable pressure in the engine room 4 of the high-pressure pump 5. If the pressure in the engine room 4 of the high-pressure pump rises above the ximal permissible value, opens the valve 11, so that via the throttle 10, an additional cooling and / or lubricating amount is discharged from the engine room 4. The engine room 4 is relieved in this way and at the same time improves the cooling and / or lubrication of the high-pressure pump 5.
  • the low-pressure circuit shown schematically in the figure, between the prefeed pump 2 and the high-pressure pump 5 also has a fuel filter 12 and a sensor 13, which is in the present case is a temperature sensor. If the detected by the sensor 13 temperature exceeds a certain limit, the flow rate of the feed pump 2 is raised until the pressure in the engine room 4 of the high-pressure pump 5 increases such that the Valve 11 opens. The now additionally fed back via the throttle 10 amount of fuel then causes an improved cooling of the high-pressure pump and thus a lowering of the temperature.

Landscapes

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

Abstract

The invention relates to a low-pressure circuit for a fuel injection system, in particular for a common-rail injection system, comprising a fuel tank (1) and a pre-feed pump (2), by means of which fuel from the fuel tank (1) can be suctioned and fed to a working chamber (4) of a high-pressure pump (5) via a fuel line (3), wherein the working chamber (4) is connected to a return line via shaft bearings. According to the invention at least two throttles (9, 10) are provided for connecting the working chamber (4) with the return (8), which throttles are in each case connected parallel to the shaft bearings (6, 7) and/or can be connected by means of a valve (11). The invention further relates to a fuel injection system comprising such a low-pressure circuit and to a method for operating a fuel injection system.

Description

Beschreibung Titel  Description title
Niederdruckkreislauf für ein Kraftstoffeinspritzsystem, Kraftstoffe! nspritzsystem sowie Verfahren zum Betreiben eines Kraftstoffeinspritzsystems  Low pressure circuit for a fuel injection system, fuels! Injection system and method for operating a fuel injection system
Die Erfindung betrifft einen Niederdruckkreislauf für ein Kraftstoffeinspritzsystem mit den Merkmalen des Oberbegriffs des Anspruchs 1. Ferner betrifft die Erfindung ein Kraftstoffeinspritzsystem mit einem solchen Niederdruckkreislauf sowie ein Verfahren zum Betreiben eines Kraftstoffeinspritzsystems. The invention relates to a low-pressure circuit for a fuel injection system having the features of the preamble of claim 1. Furthermore, the invention relates to a fuel injection system with such a low-pressure circuit and a method for operating a fuel injection system.
Stand der Technik State of the art
Aus der DE 10 2006 018 702 A1 geht eine Kraftstoff- Hochdruck- Fördereinrichtung für eine Brennkraftmaschine hervor, welche eine Hochdruckpumpe und einen Niederdruck-Strömungsweg umfasst. Der Niederdruck- Strömungsweg führt von einem Kraftstoffeinlass der Kraftstoff- Hochdruck- Fördereinrichtung zu einem Aufnahmeraum für eine Antriebswelle der Hochdruckpumpe und weiter zu mindestens einem Einlassventil der Hochdruckpumpe. Ferner ist ein Rückführ-Strömungsweg zur Rückführung von Leckage- und/oder Schmierkraftstoff vorgesehen, welcher über Wellenlager zur drehbaren Lagerung der Antriebswelle mit dem Aufnahmeraum der Hochdruckpumpe verbunden ist. Der Rückführ-Strömungsweg mündet in den Niederdruck- Strömungsweg, wobei in dem Rückführ-Strömungsweg wenigstens eine Drossel zur gezielten Einstellung der rückgeführten Kraftstoffmenge angeordnet sein kann. Dadurch soll der Wirkungsgrad der Kraftstoff-Hochdruck-Fördereinrichtung verbessert werden. DE 10 2006 018 702 A1 discloses a high-pressure fuel delivery device for an internal combustion engine, which comprises a high-pressure pump and a low-pressure flow path. The low-pressure flow path leads from a fuel inlet of the high-pressure fuel delivery device to a receiving space for a drive shaft of the high-pressure pump and further to at least one inlet valve of the high-pressure pump. Further, a return flow path for returning leakage and / or lubricating fuel is provided, which is connected via shaft bearings for rotatably supporting the drive shaft with the receiving space of the high-pressure pump. The return flow path opens into the low-pressure flow path, wherein in the return flow path at least one throttle for the targeted adjustment of the amount of fuel returned can be arranged. As a result, the efficiency of the high-pressure fuel conveyor is to be improved.
Darüber hinaus sind Niederdruckkreisläufe bekannt, welche ein Überströmventil anstelle einer Drossel zur Einstellung der rückgeführten Kraftstoffmenge vorsehen. Die Drossel weist gegenüber einem Überströmventil den Nachteil auf, dass mit Erhöhung des Zulaufdruckes keine wesentliche Erhöhung des Drosseldurch- flusses einhergeht, so dass die Gefahr besteht, dass der Zulaufdruck unzulässig hoch ansteigt. Die Abhängigkeit zwischen Drosseldurchfluss und Druckdifferenz im Zulauf- und Rücklaufbereich lässt sich durch nachfolgende Formel darstellen: In addition, low-pressure circuits are known which provide an overflow valve instead of a throttle for adjusting the amount of recirculated fuel. The throttle has the disadvantage over an overflow valve that, as the supply pressure increases, there is no significant increase in the throttle diameter. flow, so that there is a risk that the inlet pressure rises unacceptably high. The relationship between throttle flow and pressure difference in the inlet and return area can be represented by the following formula:
Das heißt, dass in kritischen Betriebssituationen, beispielweise bei gestiegenem Druck bzw. gestiegener Temperatur im Triebwerksraum der Hochdruckpumpe, die Kühlmenge nicht im erforderlichen Maß über die Drossel erhöht werden kann. Die Folge können eine Verschlechterung der Kraftstoffschmierfähigkeit und/oder ein erhöhtes Verschleißrisiko sein. Beispielsweise kann der Schmierfilm zwischen einer Laufrolle einer Stößelbaugruppe und einem Stützelement zur drehbaren Lagerung der Laufrolle auf ein kritisches Maß abnehmen, so dass es zum vorzeitigen Verschleiß der Stößelbaugruppe und damit zum Ausfall der Fördereinrichtung kommt. This means that in critical operating situations, for example with increased pressure or increased temperature in the engine room of the high-pressure pump, the cooling amount can not be increased to the required extent via the throttle. The result may be a deterioration of the fuel lubricity and / or an increased risk of wear. For example, the lubricating film between a roller of a plunger assembly and a support member for rotatably supporting the roller to a critical degree decrease, so that it comes to premature wear of the plunger assembly and thus to the failure of the conveyor.
Der vorliegenden Erfindung liegt daher die Aufgabe zugrunde, einen Niederdruckkreislauf für ein Kraftstoffeinspritzsystem bzw. ein Kraftstoffeinspritzsystem mit wenigstens einer in einem Rücklauf angeordneten Drossel anzugeben, welche in einfacher Weise eine Einstellung der rückgeführten Kraftstoffmenge ermöglicht und zugleich die vorstehend genannten Nachteile nicht aufweist. Ferner soll ein Verfahren zum Betreiben eines solchen Kraftstoffeinspritzsystems angegeben werden. The present invention is therefore an object of the invention to provide a low-pressure circuit for a fuel injection system or a fuel injection system with at least one arranged in a return throttle, which allows a simple adjustment of the amount of fuel returned and at the same time does not have the disadvantages mentioned above. Furthermore, a method for operating such a fuel injection system is to be specified.
Die Aufgabe wird gelöst durch einen Niederdruckkreislauf mit den Merkmalen des Anspruchs 1 , ein Kraftstoffeinspritzsystem mit den Merkmalen des Anspruchs 6 sowie ein Verfahren zum Betreiben eines Kraftstoffeinspritzsystems mit den Merkmalen des Anspruchs 7. Vorteilhafte Weiterbildungen der Erfindung sind in den Unteransprüchen angegeben. The object is achieved by a low-pressure circuit with the features of claim 1, a fuel injection system having the features of claim 6 and a method for operating a fuel injection system having the features of claim 7. Advantageous developments of the invention are specified in the dependent claims.
Offenbarung der Erfindung Disclosure of the invention
Der vorgeschlagene Niederdruckkreislauf für ein Kraftstoffeinspritzsystem, insbesondere ein Common-Rail-Einspritzsystem, umfasst einen Kraftstofftank und eine Vorförderpumpe, mittels welcher Kraftstoff aus dem Kraftstofftank ansaugbar und über eine Kraftstoffleitung einem Triebwerksraum einer Hochdruckpumpe zu- führbar ist. Der Triebwerksraum ist dabei über Wellenlager mit einer Rücklaufleitung verbunden. Erfindungsgemäß sind ferner zur Verbindung des Triebwerksraums mit dem Rücklauf wenigstens zwei Drosseln vorgesehen, welche jeweils parallel zu den Wellenlagern geschaltet und/oder über ein Ventil schaltbar sind. Während über die Wellenlager eine Grundleckage zur Kühlung und/oder Schmierung der Hochdruckpumpe sichergestellt ist, erfolgt die Einstellung der erforderlichen Leckagemenge über die parallel geschalteten bzw. schaltbaren Drosseln des erfindungsgemäßen Niederdruckkreislaufes. Vorzugsweise ist ein Ventil vorgesehen, über das wenigstens eine Drossel zu- oder abschaltbar ist, so dass ein weiterer, den Triebwerksraum mit dem Rücklauf verbindender, die Wellenlager umgehender Strömungsweg freigebbar bzw. verschließbar ist. Dies setzt voraus, dass wenigstens eine Drossel - ohne vorgeschaltetem Ventil - einen ersten, den Triebwerksraum mit dem Rücklauf verbindenden, die Wellenlager umgehenden Strömungsweg ausbildet, welche im Normalbetrieb der Hochdruckpumpe die er- forderliche Leckagemenge gewährleistet. Über die wenigstens eine weitere zuschaltbare Drossel kann dann bei Bedarf eine Erhöhung der Leckagemenge und auf diese Weise eine verbesserte Kühlung und/oder Schmierung der Hochdruckpumpe erzielt werden, die abhängig vom Drosselquerschnitt und dem jeweils herrschenden Druck ist. Der Drosselquerschnitt sollte bevorzugt derart gewählt werden, dass einerseits eine deutliche Verbesserung der Kühlung und/oder derThe proposed low-pressure circuit for a fuel injection system, in particular a common-rail injection system, comprises a fuel tank and a prefeed pump, by means of which fuel can be sucked in from the fuel tank and via a fuel line to an engine room of a high-pressure pump. is feasible. The engine room is connected via shaft bearings with a return line. According to the invention, at least two throttles are also provided for connecting the engine room to the return, which are each connected in parallel to the shaft bearings and / or switchable via a valve. While a basic leakage for cooling and / or lubrication of the high-pressure pump is ensured via the shaft bearings, the adjustment of the required leakage quantity takes place via the parallel-connected or switchable throttles of the low-pressure circuit according to the invention. Preferably, a valve is provided, via which at least one throttle is switched on or off, so that another, the engine room with the return connecting, the shaft bearing bypassing flow path is releasable or closable. This presupposes that at least one throttle-without an upstream valve-forms a first flow path connecting the engine room with the return, bypassing the shaft bearing, which ensures the required amount of leakage during normal operation of the high-pressure pump. If necessary, an increase in the leakage quantity and in this way improved cooling and / or lubrication of the high-pressure pump can be achieved via the at least one additional switchable throttle, which is dependent on the throttle cross-section and the respective prevailing pressure. The throttle cross-section should preferably be selected such that on the one hand a significant improvement in the cooling and / or the
Schmierung der Hochdruckpumpe erzielt wird, andererseits die Mengenbilanz des Niederdruckkreislaufes nicht verletzt wird. Demnach darf die maximal von der Vorförderpumpe zur Verfügung gestellte Menge nicht überschritten werden. Der Vorteil der Erfindung ist insbesondere darin zu sehen, dass eine Erhöhung der Leckagemenge lediglich bei Bedarf erfolgt, insbesondere bei einer kurzzeitigen, sehr hohen Belastung der Hochdruckpumpe. Beispielsweise kann in kritischen Betriebssituationen der Druck und/oder die Temperatur im Triebwerksraum der Hochdruckpumpe über einen vorgegebenen Grenzwert ansteigen, so dass die Bereitstellung einer zusätzlichen Kühl- und/oder Schmiermenge erforderlich ist. Die Bereitstellung der zusätzlichen Kühl- und/oder Schmiermenge wird dann über die wenigstens eine weitere, über ein Ventil parallel zu den Wellenlagern schaltbare Drossel gewährleistet, die dann kurzzeitig zugeschaltet wird. Dadurch wird kurzzeitig ein Anstieg der der Kühlung und/oder der Schmierung dienenden Leckagemenge bewirkt, während im Normalbetrieb der Hochdruckpumpe das Ventil geschlossen bzw. die weitere Drossel abgeschaltet ist, so dass die rückgeführte Leckagemenge auf ein Minimum reduzierbar ist. Auf diese Weise können eine Erhöhung des Wirkungsgrades des Systems und eine Reduzierung der C02-Emissionen erzielt werden. Lubrication of the high pressure pump is achieved, on the other hand, the mass balance of the low pressure circuit is not violated. Accordingly, the maximum amount provided by the prefeed pump must not be exceeded. The advantage of the invention is to be seen in particular in that an increase in the amount of leakage occurs only when necessary, especially at a short-term, very high load on the high-pressure pump. For example, in critical operating situations, the pressure and / or the temperature in the engine room of the high pressure pump may rise above a predetermined limit, so that the provision of an additional cooling and / or lubricating amount is required. The provision of the additional amount of cooling and / or lubricant is then ensured via the at least one further, via a valve parallel to the shaft bearings switchable throttle, which is then switched on for a short time. As a result, an increase in the amount of leakage serving for cooling and / or lubrication is briefly effected, while in normal operation of the high-pressure pump the valve is closed or the further throttle is switched off, so that the recirculated leakage quantity can be reduced to a minimum. In this way, an increase in the efficiency of the system and a reduction in C0 2 emissions can be achieved.
Gemäß einer bevorzugten Ausführungsform der Erfindung sind wenigstens zwei Drosseln vorgesehen, von denen zumindest eine Drossel über ein Ventil mit dem Triebwerksraum der Hochdruckpumpe verbunden und demzufolge zu- oder abschaltbar ist. According to a preferred embodiment of the invention, at least two throttles are provided, of which at least one throttle is connected via a valve to the engine room of the high-pressure pump and consequently can be switched on or off.
Gemäß einer weiteren bevorzugten Ausführungsform der Erfindung ist das Ventil ein Rückschlagventil. Es handelt sich demnach um ein passiv betätigbares Ventil, das bei Übersteigen eines vorgegebenen Öffnungsdrucks öffnet. Derartige Ventile sind besonders einfach und kostengünstig herstellbar, so dass die Herstellungskosten eines erfindungsgemäßen Niederdruckkreislaufes kaum erhöht werden. Das als Rückschlagventil ausgebildete Ventil öffnet, wenn im Triebwerksraum der Hochdruckpumpe ein gewisser Grenzdruck überschritten wird. Vorteilhafterweise ist der Öffnungsdruck des Ventils derart gewählt, dass er unter dem maximal zulässigen Druck im Triebwerksraum der Hochdruckpumpe liegt. Beispielsweise kann der Öffnungsdruck 1 bar unter dem maximal zulässigen Druck im Triebwerksraum liegen. According to a further preferred embodiment of the invention, the valve is a check valve. It is therefore a passively operable valve that opens when exceeding a predetermined opening pressure. Such valves are particularly simple and inexpensive to produce, so that the production cost of a low pressure circuit according to the invention are hardly increased. The designed as a check valve valve opens when a certain limit pressure is exceeded in the engine room of the high pressure pump. Advantageously, the opening pressure of the valve is selected such that it is below the maximum allowable pressure in the engine room of the high-pressure pump. For example, the opening pressure may be 1 bar below the maximum allowable pressure in the engine room.
Darüber hinaus kann das Ventil auch als aktiv betätigbares Ventil ausgebildet sein, das mit einer Steuereinheit verbunden ist. Die Steuereinheit ist weiterhin bevorzugt mit wenigstens einem Sensor zur Erfassung eines Drucks und/oder einer Temperatur im Niederdruckkreislauf verbunden, so dass bei Überschreiten eines voreingestellten Grenzwertes, das Ventil geöffnet wird. In addition, the valve can also be designed as an actively operable valve, which is connected to a control unit. The control unit is furthermore preferably connected to at least one sensor for detecting a pressure and / or a temperature in the low-pressure circuit, so that when a preset limit value is exceeded, the valve is opened.
Weiterhin bevorzugt ist die Vorförderpumpe eine geregelte Elektrokraftstoffpum- pe. Durch Verwendung einer geregelten Elektrokraftstoffpumpe als Vorförderpumpe ist der Einsatz einer Zumesseinheit und/oder eines Überströmventils entbehrlich. Da Konzepte mit Überströmventil regelmäßig, insbesondere bei vorgegebenem Innenraumdruck und steiler Kennlinie des Überströmventils, den Nachteil aufweisen, dass große Leckagemengen rückgeführt werden müssen, ist der Wegfall des Überströmventils grundsätzlich zu begrüßen. Vorteilhafterweise ist zwischen der Vorförderpumpe und der Hochdruckpumpe wenigstens ein Kraftstofffilter angeordnet. Der Kraftstoffilter dient dem Schutz der Hochdruckpumpe vor schädlichen, im Kraftstoff enthaltenen Partikeln. Alternativ oder ergänzend kann zwischen der Vorförderpumpe und der Hochdruckpumpe 5 wenigstens ein Sensor, vorzugsweise ein Druck- und/oder Temperatursensor, zur Erfassung des Kraftstoffdrucks und/oder der Kraftstofftemperatur im Niederdruckkreislauf, insbesondere in der Kraftstoffleitung und/oder im Triebwerksraum der Hochdruckpumpe, angeordnet sein. Die mittels des Sensors erfassten Werte können der Regelung einer als Elektrokraftstoffpumpe ausgelegten Vorförder- l o pumpe und/oder der Betätigung eines Ventils dienen, über welches wenigstens eine in einem Rücklauf angeordnete Drossel zu- oder abschaltbar ist. Furthermore, the prefeed pump is preferably a regulated electric fuel pump. By using a regulated electric fuel pump as prefeed pump, the use of a metering unit and / or an overflow valve is dispensable. Since concepts with overflow regularly, especially at a given interior pressure and steep curve of the spill valve, have the disadvantage that large leakage quantities must be returned, the omission of the spill valve is basically welcome. Advantageously, at least one fuel filter is arranged between the prefeed pump and the high-pressure pump. The fuel filter protects the high-pressure pump from harmful particles contained in the fuel. Alternatively or additionally, at least one sensor, preferably a pressure and / or temperature sensor, for detecting the fuel pressure and / or the fuel temperature in the low-pressure circuit, in particular in the fuel line and / or in the engine room of the high-pressure pump, may be arranged between the prefeed pump and the high-pressure pump 5 , The values detected by means of the sensor can be used to control a prefeed pump designed as an electric fuel pump and / or to actuate a valve, via which at least one throttle arranged in a return can be connected or disconnected.
Des Weiteren vorteilhafterweise ist die Kraftstoffleitung über den Triebwerksraum mit einem Zulauf der Hochdruckpumpe verbunden. Das heißt, dass der gesamte über die Vorförderpumpe geförderte Kraftstoffstrom zunächst in den Triebwerksraum der Hochdruckpumpe gelangt und von dort aus als Förderstrom dem Zulauf der Hochdruckpumpe zugeführt oder als der Kühlung und/oder Schmierung der Hochdruckpumpe dienender Leckagestrom über die Wellenlager sowie die parallel geschalteten bzw. schaltbaren Drosseln abgeführt wird. Furthermore, advantageously, the fuel line is connected via the engine room with an inlet of the high-pressure pump. This means that the entire conveyed via the feed pump fuel flow first passes into the engine room of the high pressure pump and fed from there as a flow to the inlet of the high pressure pump or as the cooling and / or lubrication of the high pressure pump serving leakage flow through the shaft bearings and the parallel connected or switchable chokes is removed.
Das ferner zur Lösung der eingangs genannten Aufgabe vorgeschlagene Kraftstoffeinspritzsystem zum Einspritzen von Kraftstoff in den Brennraum einer Brennkraftmaschine weist einen erfindungsgemäßen Niederdruckkreislauf auf. Das vorgeschlagene Kraftstoffeinspritzsystem zeichnet sich demnach durch einen verbesserten Wrkungsgrad und eine Reduzierung der C02-Emissionen aus. Ferner sinkt die Beanspruchung der Hochdruckpumpe, da unzulässig hohe Druck- und/oder Temperaturanstiege im Triebwerksraum der Hochdruckpumpe verhindert werden. Dadurch steigt die Lebensdauer der Hochdruckpumpe. The further proposed for the solution of the above-mentioned object fuel injection system for injecting fuel into the combustion chamber of an internal combustion engine has a low pressure circuit according to the invention. The proposed fuel injection system is therefore characterized by an improved degree of efficiency and a reduction in C0 2 emissions. Furthermore, the stress on the high-pressure pump decreases because impermissibly high pressure and / or temperature increases in the engine room of the high-pressure pump are prevented. This increases the life of the high-pressure pump.
30 Schließlich wird ein Verfahren zum Betreiben eines erfindungsgemäßen Kraftstoffeinspritzsystems vorgeschlagen, bei welchem der Kraftstoff druck und/oder die Kraftstofftemperatur im Niederdruckkreislauf, vorzugsweise in der Kraftstoffleitung und/oder im Triebwerksraum der Hochdruckpumpe erfasst wird bzw. werden und bei Überschreiten eines vorgegebenen Grenzwertes die FörderleistungFinally, a method for operating a fuel injection system according to the invention is proposed in which the fuel pressure and / or the fuel temperature in the low-pressure circuit, preferably in the fuel line and / or in the engine room of the high-pressure pump is detected and when exceeding a predetermined limit, the flow rate
35 der Vorförderpumpe bis zum Öffnen des Ventils angehoben wird, so dass die stromabwärts des Ventils angeordnete Drossel zugeschaltet wird. Die der Küh- lung und/oder Schmierung der Hochdruckpumpe dienende Leckagemenge kann demnach über eine zuschaltbare Drossel erhöht werden, so dass ein unzulässig hoher Druck bzw. eine unzulässig hohe Temperatur im Triebwerksraum der Hochdruckpumpe wirksam vermieden werden. In kritischen Betriebssituationen kann demnach die Kühlung und/oder Schmierung der Hochdruckpumpe verbessert werden, so dass einer Beschädigung der Hochdruckpumpe entgegengewirkt wird. 35 of the prefeed pump is raised until the valve is opened, so that the downstream of the valve arranged throttle is switched on. The cow's Ventilation and / or lubrication of the high-pressure pump serving leakage amount can therefore be increased via a switchable throttle, so that an impermissibly high pressure or an impermissibly high temperature in the engine room of the high-pressure pump can be effectively avoided. Accordingly, in critical operating situations, the cooling and / or lubrication of the high-pressure pump can be improved, so that damage to the high-pressure pump is counteracted.
Eine bevorzugte Ausführungsform der Erfindung wird nachfolgend anhand der beigefügten Zeichnung näher erläutert. Diese zeigt eine schematische Darstellung eines erfindungsgemäßen Niederdruckkreislaufes eines Kraftstoffeinspritzsystems. A preferred embodiment of the invention will be explained in more detail with reference to the accompanying drawings. This shows a schematic representation of a low-pressure circuit according to the invention of a fuel injection system.
Ausführliche Beschreibung der Zeichnung Detailed description of the drawing
Der schematisch dargestellte erfindungsgemäße Niederdruckkreislauf umfasst eine als regelbare Elektrokraftstoffpumpe ausgeführte Vorförderpumpe 2, mittels welcher Kraftstoff aus einem Kraftstofftank 1 über eine Kraftstoffleitung 3 einer Hochdruckpumpe 5 zuführbar ist. Die Kraftstoffleitung 3 mündet dabei in einen Triebwerksraum 4 der Hochdruckpumpe 5, in dem die zugeführte Kraftstoff menge in eine Fördermenge und eine Kühl- und/oder Schmiermenge geteilt wird. Die Fördermenge wird über einen Zulauf 14 einem Hochdruckbereich (nicht dargestellt) der Hochdruckpumpe 5 zugeführt, während die Kühl- und/oder Schmiermenge über einen Rücklauf 8 zurück in den Kraftstofftank 1 gelangt. Der Rück- lauf 8 ist über Wellenlager 6, 7 der Hochdruckpumpe 5 mit dem Triebwerksraum 4 verbunden. Ferner ist eine parallel zu den Wellenlagern 6, 7 geschaltete Drossel 9 vorgesehen, welche den Rücklauf 8 mit dem Triebwerksraum 4 der Hochdruckpumpe 5 verbindet. Die Wellenlager 6, 7 und die parallel geschaltete Drossel 9 stellen eine Mindestkühlmenge bzw. Mindestschmiermenge sicher. The schematically illustrated low-pressure circuit according to the invention comprises a prefeed pump 2 designed as a controllable electric fuel pump, by means of which fuel can be supplied from a fuel tank 1 via a fuel line 3 to a high-pressure pump 5. The fuel line 3 discharges into an engine room 4 of the high pressure pump 5, in which the amount of fuel supplied is divided into a flow rate and a cooling and / or lubricating amount. The delivery rate is fed via an inlet 14 to a high-pressure area (not shown) of the high-pressure pump 5, while the amount of coolant and / or lubricant passes back into the fuel tank 1 via a return line 8. The return 8 is connected to the engine room 4 via shaft bearings 6, 7 of the high-pressure pump 5. Further, a parallel to the shaft bearings 6, 7 connected throttle 9 is provided, which connects the return 8 with the engine room 4 of the high-pressure pump 5. The shaft bearings 6, 7 and the parallel-connected throttle 9 ensure a minimum amount of cooling or minimum amount of lubricant.
Darüber hinaus weist der in der Figur schematisch dargestellte erfindungsgemäße Niederdruckkreislauf eine weitere Drossel 10 auf, welche über ein Ventil 11 ebenfalls parallel zu den Wellenlagern 6, 7 schaltbar ist. Das Ventil 11 ist vorliegend als einfaches Rückschlagventil ausgebildet, dessen Öffnungsdruck unter dem maximal zulässigen Druck im Triebwerksraum 4 der Hochdruckpumpe 5 liegt. Steigt der Druck im Triebwerksraum 4 der Hochdruckpumpe über den ma- ximal zulässigen Wert an, öffnet das Ventil 11 , so dass über die Drossel 10 eine zusätzliche Kühl- und/oder Schmiermenge aus dem Triebwerksraum 4 abgeführt wird. Der Triebwerksraum 4 wird auf diese Weise entlastet und zugleich die Kühlung und/oder Schmierung der Hochdruckpumpe 5 verbessert. In addition, the low-pressure circuit according to the invention shown schematically in the figure has a further throttle 10, which is also connected via a valve 11 parallel to the shaft bearings 6, 7 switchable. The valve 11 is presently designed as a simple check valve whose opening pressure is below the maximum allowable pressure in the engine room 4 of the high-pressure pump 5. If the pressure in the engine room 4 of the high-pressure pump rises above the ximal permissible value, opens the valve 11, so that via the throttle 10, an additional cooling and / or lubricating amount is discharged from the engine room 4. The engine room 4 is relieved in this way and at the same time improves the cooling and / or lubrication of the high-pressure pump 5.
Der in der Figur schematisch dargestellte Niederdruckkreislauf weist zwischen der Vorförderpumpe 2 und der Hochdruckpumpe 5 ferner einen Kraftstofffilter 12 sowie einen Sensor 13 auf, wobei es sich vorliegend um einen Temperatursensor handelt. Der Sensor 13 dient der Regelung der Elektrokraftstoff pumpe bzw. der Vorförderpumpe 2. Sofern die vom Sensor 13 erfasste Temperatur einen bestimmten Grenzwert übersteigt, wird die Förderleistung der Vorförderpumpe 2 angehoben wird, bis der Druck im Triebwerksraum 4 der Hochdruckpumpe 5 derart ansteigt, dass das Ventil 11 öffnet. Die nunmehr zusätzlich über die Drossel 10 rückgeführte Kraftstoffmenge bewirkt dann eine verbesserte Kühlung der Hochdruckpumpe und damit ein Absenken der Temperatur. The low-pressure circuit shown schematically in the figure, between the prefeed pump 2 and the high-pressure pump 5 also has a fuel filter 12 and a sensor 13, which is in the present case is a temperature sensor. If the detected by the sensor 13 temperature exceeds a certain limit, the flow rate of the feed pump 2 is raised until the pressure in the engine room 4 of the high-pressure pump 5 increases such that the Valve 11 opens. The now additionally fed back via the throttle 10 amount of fuel then causes an improved cooling of the high-pressure pump and thus a lowering of the temperature.

Claims

Niederdruckkreislauf für ein Kraftstoffeinspritzsystem, insbesondere ein Common-Rail-Einspritzsystem, umfassend einen Kraftstofftank (1) und eine Vorförderpumpe (2), mittels welcher Kraftstoff aus dem Kraftstofftank (1) ansaugbar und über eine Kraftstoffleitung (3) einem Triebwerksraum (4) einer Hochdruckpumpe (5) zuführbar ist, wobei der Triebwerksraum (4) über Wellenlager (6, 7) mit einer Rücklaufleitung (8) verbunden ist, Low-pressure circuit for a fuel injection system, in particular a common rail injection system, comprising a fuel tank (1) and a pre-feed pump (2), by means of which fuel can be sucked in from the fuel tank (1) and via a fuel line (3) to an engine compartment (4) of a high-pressure pump (5) can be supplied, the engine room (4) being connected to a return line (8) via shaft bearings (6, 7),
dadurch gekennzeichnet, dass ferner zur Verbindung des Triebwerksraums (4) mit dem Rücklauf (8) wenigstens zwei Drosseln (9, 10) vorgesehen sind, welche jeweils parallel zu den Wellenlagern (6, 7) geschaltet und/oder über ein Ventil (1 1) schaltbar sind. characterized in that at least two throttles (9, 10) are also provided for connecting the engine room (4) to the return line (8), each of which is connected in parallel to the shaft bearings (6, 7) and / or via a valve (1 1 ) can be switched.
Niederdruckkreislauf nach Anspruch 1 , Low pressure circuit according to claim 1,
dadurch gekennzeichnet, dass das Ventil (1 1) ein Rückschlagventil ist. Niederdruckkreislauf nach Anspruch 1 oder 2, characterized in that the valve (1 1) is a check valve. Low pressure circuit according to claim 1 or 2,
dadurch gekennzeichnet, dass die Vorförderpumpe (2) eine geregelte Elektrokraftstoffpumpe ist. characterized in that the pre-feed pump (2) is a regulated electric fuel pump.
Niederdruckkreislauf nach einem der vorhergehenden Ansprüche, Low pressure circuit according to one of the preceding claims,
dadurch gekennzeichnet, dass zwischen der Vorförderpumpe characterized in that between the pre-feed pump
(2) und der Hochdruckpumpe (5) ein Kraftstofffilter (12) und/oder wenigstens ein Sensor (13), vorzugsweise ein Druck- und/oder Temperatursensor, angeordnet ist bzw. sind. (2) and the high pressure pump (5) a fuel filter (12) and/or at least one sensor (13), preferably a pressure and/or temperature sensor, is or are arranged.
Niederdruckkreislauf nach einem der vorhergehenden Ansprüche, Low pressure circuit according to one of the preceding claims,
dadurch gekennzeichnet, dass die Kraftstoffleitung characterized in that the fuel line
(3) über den Triebwerksraum (3) via the engine room
(4) mit einem Zulauf (14) der Hochdruckpumpe (4) with an inlet (14) of the high-pressure pump
(5) verbunden ist. (5) is connected.
6. Kraftstoffeinspritzsystem zum Einspritzen von Kraftstoff in den Brennraum einer Brennkraftmaschine mit einem Niederdruckkreislauf nach einem der vorhergehenden Ansprüche. 6. Fuel injection system for injecting fuel into the combustion chamber of an internal combustion engine with a low-pressure circuit according to one of the preceding claims.
7. Verfahren zum Betreiben eines Kraftstoffeinspritzsystems mit den Merkmalen des Anspruchs 6, 7. Method for operating a fuel injection system with the features of claim 6,
dadurch gekennzeichnet, dass der Kraftstoffdruck und/oder die Kraftstofftemperatur im Niederdruckkreislauf, vorzugsweise in der Kraftstoffleitung (3) und/oder im Triebwerksraum (4) erfasst wird und bei Überschreiten eines vorgegebenen Grenzwertes die Förderleistung der Vorförderpumpe (2) bis zum Öffnen des Ventils (1 1) angehoben wird, so dass die stromabwärts des Ventils (1 1) angeordnete Drossel (10) zugeschaltet wird. characterized in that the fuel pressure and/or the fuel temperature in the low-pressure circuit, preferably in the fuel line (3) and/or in the engine room (4), is detected and, if a predetermined limit value is exceeded, the delivery rate of the pre-feed pump (2) is monitored until the valve opens ( 1 1) is raised so that the throttle (10) arranged downstream of the valve (1 1) is switched on.
EP13727584.8A 2012-07-11 2013-05-31 Low-pressure circuit for a fuel injection system, fuel injection system and method for operating a fuel injection system Withdrawn EP2890888A1 (en)

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PCT/EP2013/061304 WO2014009056A1 (en) 2012-07-11 2013-05-31 Low-pressure circuit for a fuel injection system, fuel injection system and method for operating a fuel injection system

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Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101338805B1 (en) * 2012-06-14 2013-12-06 현대자동차주식회사 Feul supply apparatus for gdi engine having reduced pressure pulsation
DE102016200232A1 (en) * 2016-01-12 2017-07-13 Continental Automotive Gmbh Fuel injection system
DE102018108406A1 (en) 2017-06-22 2018-12-27 Denso Corporation High pressure fuel pump and fuel supply system
CN109654528B (en) * 2018-12-14 2020-05-08 重庆军通汽车有限责任公司 Fuel oil system of smoke generator
FR3110195B1 (en) * 2020-05-18 2022-08-19 Safran Aerosystems Aircraft comprising in its fuel tank a chamber equipped with a sensor

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19926308A1 (en) * 1999-06-09 2000-12-21 Bosch Gmbh Robert Pump assembly for fuel
US6675570B2 (en) * 2000-06-15 2004-01-13 Argo-Tech Corporation Low-cost general aviation fuel control system
DE10059012A1 (en) * 2000-11-28 2002-06-13 Bosch Gmbh Robert Fuel injection system with fuel preheating and fuel-cooled pressure control valve
EP1321663A3 (en) * 2001-12-19 2003-07-02 Robert Bosch Gmbh Fuel injection device for an internal combustion engine
JP3915718B2 (en) * 2003-03-11 2007-05-16 株式会社デンソー Fuel supply pump
US7025044B1 (en) * 2003-07-16 2006-04-11 R. H. Sheppard Co., Inc. Pump assembly and method
DE102005027851A1 (en) * 2005-06-16 2006-12-21 Robert Bosch Gmbh Fuel injection system for an internal combustion engine
DE102006013165A1 (en) * 2006-03-22 2007-09-27 Robert Bosch Gmbh High-pressure fuel pump and fuel injection system for an internal combustion engine
DE102006018702A1 (en) 2006-04-21 2007-10-25 Robert Bosch Gmbh Fuel high-pressure conveying device
JP2010138706A (en) * 2008-12-09 2010-06-24 Aisan Ind Co Ltd Fuel vapor pressure measuring device
DE102009001563A1 (en) * 2009-03-16 2010-09-23 Robert Bosch Gmbh high pressure pump
DE102009027335A1 (en) * 2009-06-30 2011-01-05 Robert Bosch Gmbh Fuel system for an internal combustion engine
DE102010002801A1 (en) * 2010-03-12 2011-09-15 Robert Bosch Gmbh Fuel injection system of an internal combustion engine
DE102010064374B3 (en) * 2010-12-30 2012-07-12 Continental Automotive Gmbh Fuel injection system of an internal combustion engine and associated pressure control method, control unit and motor vehicle

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
None *
See also references of WO2014009056A1 *

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WO2014009056A1 (en) 2014-01-16
US20150152829A1 (en) 2015-06-04

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