EP0050710B1 - Fuel injection system - Google Patents

Fuel injection system Download PDF

Info

Publication number
EP0050710B1
EP0050710B1 EP81105545A EP81105545A EP0050710B1 EP 0050710 B1 EP0050710 B1 EP 0050710B1 EP 81105545 A EP81105545 A EP 81105545A EP 81105545 A EP81105545 A EP 81105545A EP 0050710 B1 EP0050710 B1 EP 0050710B1
Authority
EP
European Patent Office
Prior art keywords
valve
pressure
fuel injection
valve member
fuel
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP81105545A
Other languages
German (de)
French (fr)
Other versions
EP0050710A1 (en
Inventor
Rudolf Babitzka
Walter Beck
Walter Schlagmüller
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=6114997&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0050710(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP0050710A1 publication Critical patent/EP0050710A1/en
Application granted granted Critical
Publication of EP0050710B1 publication Critical patent/EP0050710B1/en
Expired legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
    • F02M63/0012—Valves
    • F02M63/0014—Valves characterised by the valve actuating means
    • F02M63/0015—Valves characterised by the valve actuating means electrical, e.g. using solenoid
    • F02M63/0026—Valves characterised by the valve actuating means electrical, e.g. using solenoid using piezoelectric or magnetostrictive actuators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M47/00—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure
    • F02M47/02—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure of accumulator-injector type, i.e. having fuel pressure of accumulator tending to open, and fuel pressure in other chamber tending to close, injection valves and having means for periodically releasing that closing pressure
    • F02M47/027—Electrically actuated valves draining the chamber to release the closing pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • 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
    • F02M59/20—Varying fuel delivery in quantity or timing
    • F02M59/36—Varying fuel delivery in quantity or timing by variably-timed valves controlling fuel passages to pumping elements or overflow passages
    • F02M59/366—Valves being actuated electrically
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B1/00—Engines characterised by fuel-air mixture compression
    • F02B1/02—Engines characterised by fuel-air mixture compression with positive ignition
    • F02B1/04—Engines characterised by fuel-air mixture compression with positive ignition with fuel-air mixture admission into cylinder

Definitions

  • the invention relates to a fuel injection system for an internal combustion engine according to the preamble of the main claim.
  • electrically controllable valve devices for. B. according to DE-A-1 917927, switching times of 10- 3 seconds are achieved. It has been shown that the switching edges achieved here are not yet steep enough. In particular, the shortening of the spraying time has a lower limit.
  • the fuel injection system according to the invention for internal combustion engines with the characterizing features of the independent claim has the advantage that it can achieve response times in the microsecond range.
  • FIG. 1 of the drawing a first exemplary embodiment of a fuel injection system for an internal combustion engine is shown in a semi-schematic representation.
  • This fuel injection system essentially consists of five main parts: a fuel tank 1, a fuel delivery pump 2 designed approximately as a piston pump, an injection nozzle 3, a valve device consisting of two valves 4, 5 and an electronic control unit 6.
  • the pump 2 sucks the fuel from the tank 1 and delivers it through a feed line 7 to the inlet bore 8 of the injection nozzle 3.
  • An overflow line 49 is connected to the feed line 7 and leads to the inlets 9 and 10 of the valves 4 and 5.
  • the injection nozzle 3 distributes and atomizes the fuel in the combustion chamber of the internal combustion engine.
  • the injection nozzle is a liquid-controlled needle valve, the valve needle 11 of which is pressed onto the valve seat 13 by a spring 12. Above the nozzle opening 14 there is an annular space 15 into which the inlet bore 8 opens. The valve needle is lifted from its seat by the pressure prevailing in the annular space 15 as soon as the pressure forces exceed the forces of the spring 12.
  • the electrically controllable valve 4 is shown as a detail in FIG. 2. It has a housing 16 which has a valve bore 17. In the valve bore 17, a piston-like valve member 18 is tightly and slidably guided.
  • the inlet 10 is formed by a bore which has a larger diameter than the valve bore 17 running coaxially therewith. At the transition from the inlet 10 to the valve bore 17 a hollow conical seat 19 is formed. A conical sealing surface 20 cooperates with this seat surface and is arranged on a mushroom-shaped extension of the valve member 18. A compression spring 21, which is arranged in the valve bore 17 and is supported on the one hand on the end face of the valve member facing away from the sealing surface 20 and on the other hand on a stopper 22 closing the mouth of the valve bore 17, holds the valve 4 in the open position shown in FIG.
  • An annular chamber 23, into which an outlet 24 opens, is arranged coaxially to the valve bore 17 at the inside of the end of the seat surface 19 facing away from the inlet 10.
  • a guide bore 25 opens at right angles to the direction of movement of the valve member 18, in which a clamping punch 26 is arranged so as to be movable.
  • the clamping stamp 26 is part of an electrically controllable actuator 27.
  • the actuator 27 consists of several, one Column 28 layered piezoelectric disks 29, which are arranged in an insulating housing 30.
  • the piezoelectric disks 29 are electrically connected in parallel and can be connected to DC voltage via supply lines 31, 32.
  • the column 28 is attached to a cover 33 which closes a material bore 34 in the housing 16.
  • the guide bore 25, in which the clamping punch 26 is located, opens into the bottom of the blind bore 34.
  • the distance between the outer surface of the valve member 18 and the slightly concave end face of the clamping plunger 26 is only a few thousandths of a millimeter. If a direct current is now applied to the feed line 31, 32, the piezoelectric disks 29 expand under the influence of the applied electric field and at the same time their diameters contract in the direction of the column axis such that the clamping plunger 26 is displaced in the direction of the valve member 18.
  • the clamp 26 comes to rest on the outer surface of the valve member 18 and holds the valve member 18 against the opposite wall of the valve bore 17. Due to the high clamping force, the valve member 18 is held in frictional contact with the opposite wall of the valve bore such that a movement of the Valve member is excluded.
  • a direct voltage is applied to the supply lines 31, 32, as a result of which the clamping plunger clamps the valve member in the position raised from the seat surface 19.
  • a fuel flow flowing from the inlet 10 to the outlet 24 builds up a pressure at the throttle point formed by the sealing surface 20 with the seat surface 19, which pressure can close the valve in the non-locked position.
  • the direct surface 20 of the valve member 18 can only move onto the seat surface 19 when the DC voltage applied to the actuator 27 is switched off.
  • the control voltage is only switched off when the full, achievable throttle pressure P4 is applied to the valve element.
  • Valve 5 is also electrically controllable. It in turn has a housing 36 which has a valve bore 37.
  • a piston-like valve member 38 which has a conical sealing surface 40, is in turn guided in the valve bore 37 in a sealed and sliding manner.
  • the sealing surface works together with a corresponding, hollow-conical seat 39.
  • the seat is arranged at the transition of the inlet 9 into the coaxially arranged valve bore 37, which has a larger diameter than the inlet 9.
  • annular chamber 43 is arranged coaxially with the valve bore 37, into which an outlet 44 of the valve 5 opens.
  • a compression spring 41 is supported, the other end of which rests on a stopper 42.
  • a guide bore 45 opens out again at right angles to the direction of movement of the valve member, in which a clamping plunger 46 is movably arranged.
  • the clamping plunger 46 is again part of an electrically controllable actuator 47, which corresponds completely to the electrical actuator 27 of the valve according to FIG. 2.
  • a control voltage can also be applied to this steeper 47 via supply lines 51, 52.
  • the outputs 24, 44 of the valves 4, 5 forming the valve device of the fuel injection system shown in FIG. 1 are connected to a return line 55 which leads back to the tank 1
  • the feed lines 31, 32 to the electrical actuator 27 of the valve 4 and the feed lines 51, 52 to the actuator 47 of the valve 5 are connected to the already mentioned electronic control unit 6.
  • the electronic control unit supplies control voltages which, for. B. depend on the intake manifold pressure, the engine speed and other correction variables.
  • the influencing factors are detected on the engine by mechanical-electrical transducers and input to the control unit in a manner known per se as electrical quantities.
  • the transducers are, for example, injection triggers in the distributor, pressure sensors, temperature sensors, etc.
  • the function of the fuel injection system shown in FIG. 1 of the drawing is as follows: If the pump 2 is a piston pump, for example, used in injection systems for diesel engines, the volume flow indicated in FIG. 4 will result over time. At time t, the delivery volume flow of the pump 2 begins to increase. At this time, the valve members 18, 38 of the valves 4, 5 are in the position shown in FIG. 1, in which - as can be seen in FIG. 5 - a control voltage is present at the points 27 and 47. At the same time, the valve member 18 of the valve 4 is in its maximum stroke position (curve S4 in FIG. 6). The valve member 38 of the valve 5 is located on its seat 39, ie in the closed position, which corresponds to a zero stroke position (curve s 5 in FIG.
  • the pump 2 it is of course also possible to design the pump 2 as a continuously delivering pump; operation from a memory would also be conceivable.
  • the second exemplary embodiment of a fuel injection system for an internal combustion engine shown in FIG. 9 of the drawing is equipped with a continuously delivering pump 62.
  • This fuel injection system also consists again of a fuel tank 61, the pump 62, an injection nozzle 63. a valve device consisting of two valves 64, 65 and an electronic control unit 66.
  • the pump 62 conveys the fuel drawn from the tank 61 into a reservoir 60
  • the reservoir 60 is in turn connected via a feed line 67 on the one hand to the inlet bore 68 of the injection nozzle 63 and on the other hand to the inlet 69 of the valve 65.
  • the injection nozzle 63 is also a liquid-controlled needle valve, the valve needle 71 of which is held on the valve seat 73 by aen aut aie the rear side of a control pressure 72 which is connected to the needle 71.
  • An annular space 75, into which the inlet bore 68 opens, is again located above the nozzle opening 74.
  • the valve needle 71 is lifted from its seat due to the essentially constant pressure prevailing in the annular space 75 because of the storage volume 60 as soon as the forces exerted by the control pressure on the control piston 72 fall below the forces exerted on the valve needle 11 in the annular space 75 by the storage pressure resulting forces fall.
  • the electrically controllable valve 64 corresponds completely to the valve shown in FIG. 3.
  • the electrically controllable valve 65 also corresponds to the valve shown in FIG. 3 except for a modification which is explained in more detail below.
  • the reference numbers used in FIG. 3 are therefore used in the following description, insofar as there is agreement.
  • the inlet bore 69 of the valve 65 is connected to the accumulator 60.
  • the inlet bore 69 could be connected to another pressure source that is independent of the reservoir 60.
  • the outlet 84 of the valve 65 is connected to a control line 89 which opens into the space of the injection nozzle 63 in which the piston 72 is located.
  • the back of the valve member 38 'of the valve 65 is pressure balanced via an adjustable throttle 85. (For the purpose of the valve shown in FIG. 3, only the plug 42 has to have a coaxial bore, via which the valve bore 37 can be connected to the outlet 84 via the throttle 85).
  • the actuator 47 ' which has a clamp 46', is connected to the electronic control device 66 via supply lines 51 ', 52'.
  • the control line 89 is in turn connected to the input 70 of the valve 64.
  • the valve 64 corresponds completely to the embodiment described in FIG. 3.
  • the outlet 94 of the valve 64 is connected to the tank via a return line 95.
  • the valve 64 also has an electrically controllable actuator 47 "with a clamping plunger 46" which, like the valve 65, can clamp the valve member 38 "in its closed position.
  • the electrical actuator 47" is also connected to the via supply lines 51 ", 52" electronic control unit 66 connected.
  • the function of the fuel injection system shown in FIG. 9 is as follows: It is assumed that in the operating position shown in FIG. 9 there is zero p s in the control line 89 at the time (FIG. 12). The pressure p s is, for example, approximately 200 bar.
  • the valve members 38 '; of the valve 65 and 38 "of the valve 64 are - since at the actuators 47 ', 47".
  • a control voltage U 65 and U e4 (FIG. 10) is present - clamped in its closed position (curves s 64 and s 65 in FIG. 11). Because the effective area of the control piston 72 is larger than the hydraulically effective area of the valve needle 71 in the annular space 75, the valve needle 71 is held on the seat 73.
  • valve member 38 is very quickly lifted off its seat under the effect of pressure p s prevailing in control line 89 . Since the pressure force is already fully built up when the clamping force exerted by the actuator 47 "is released, a very steep switching edge of approximately 100 microseconds is also achieved with this valve. Since the control line 89 is now connected to the tank 61 via the return line 95, The pressure in the control line 89 drops to the value p o . Since the closing force acting on the control piston 72 is no longer present, the valve needle 71 is lifted from the pressure prevailing in the annular space 75 and the fuel can flow through the open nozzle opening 74 into the combustion chamber of the Coming to the internal combustion engine.
  • the electronic control unit 66 now switches off the control voltage present at the actuator 47 'of the valve 65.
  • the valve member 38 ' is now lifted from its seat against the force of the spring 41'.
  • the control pressure Ps (FIG. 12) now builds up again in the control line 89.
  • the valve needle 71 is now pressed back onto its seat 73. The end of the period in which the fuel was able to get into the combustion chamber from the injection nozzle 63 has thus reached the injection duration t 3 -t l -.

Landscapes

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

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einer Kraftstoffeinspritzanlage für einen Verbrennungsmotor nach der Gattung des Hauptanspruchs. Bei in bekannten Einspritzanlagen verwendeten, ausreichend optimierten, elektrisch ansteuerbaren Ventileinrichtungen, z. B. nach der DE-A-1 917927, werden Schaltzeiten von 10-3 Sekunden erreicht. Es hat sich gezeigt, daß die hierbei erreichten Schaltflanken noch nicht steil genug sind. Insbesondere der Verkürung der Spritzdauer ist so eine untere Grenze gesetzt.The invention relates to a fuel injection system for an internal combustion engine according to the preamble of the main claim. When used in known injection systems, sufficiently optimized, electrically controllable valve devices, for. B. according to DE-A-1 917927, switching times of 10- 3 seconds are achieved. It has been shown that the switching edges achieved here are not yet steep enough. In particular, the shortening of the spraying time has a lower limit.

Vorteile der ErfindungAdvantages of the invention

Die erfindungsgemäße Kraftstoffeinspritzanlage für Verbrennungsmotoren mit den kennzeichnenden Merkmalen des unabhängigen Anspruchs hat demgegenüber den Vorteil, daß bei ihr Ansprechzeiten im Mikrosekundenbereich erzielt werden können.The fuel injection system according to the invention for internal combustion engines with the characterizing features of the independent claim has the advantage that it can achieve response times in the microsecond range.

Durch die in den abhängigen Ansprüchen aufgeführten Maßnahmen sind vorteilhafte Weiterbildungen und Verbesserungen der im unabhängigen Anspruch angegebenen Kraftstoffeinspritzanlagen möglich. Zur Erzielung von besonders kurzen Ansprechzeiten, im Bereich von 10-5 s besteht der Steiler aus einer aus piezoelektrischen Scheiben geschichteten Säule, deren Säulenachse zumindest nahezu senkrecht zur Bewegungsachse des Ventilglieds steht.The measures listed in the dependent claims allow advantageous developments and improvements of the fuel injection systems specified in the independent claim. In order to achieve particularly short response times, in the range of 10- 5 s is the steep of a laminated piezoelectric disks from column whose column axis is at least substantially perpendicular to the axis of movement of the valve member.

Zeichnungdrawing

Zwei Ausführungsbeispiele der Erfindung sind in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Es zeigen

  • Figur 1 ein erstes Ausführungsbeispiel einer Kraftstoffeinspritzanlage für einen Verbrennungsmotor,
  • Figur 2 und 3 zwei in der Einspritzanlage verwendete, elektrisch ansteuerbare Ventile,
  • Figur 4 den Verlauf des Fördervolumens,
  • Figur 5 den Verlauf der Steuerspannungen für die elektrisch ansteuerbaren Ventile,
  • Figur 6 den Hubverlauf der Ventile der Ventileinrichtung,
  • Figur 7 den Druckverlauf in der Einspritzanlage gemäß Figur 1,
  • Figur 8 den Verlauf der Einspritzmenge jeweils über der Zeit aufgetragen,
  • Figur 9 ein zweites Ausführungsbeispiel einer Einspritzanlage,
  • Figur 10 den Verlauf der Steuerspannungen der in der Einspritzanlage gemäß Figur 9 verwendeten Ventile,
  • Figur 11 den Hubverlauf der Ventile der Einspritzeinrichtung gemäß Figur 9 und
  • Figur 12 den Steuerdruckverlauf in der Einspritzanlage.
Two embodiments of the invention are shown in the drawing and explained in more detail in the following description. Show it
  • FIG. 1 shows a first exemplary embodiment of a fuel injection system for an internal combustion engine,
  • FIGS. 2 and 3, two electrically controllable valves used in the injection system,
  • FIG. 4 shows the course of the delivery volume,
  • FIG. 5 shows the course of the control voltages for the electrically controllable valves,
  • FIG. 6 the stroke course of the valves of the valve device,
  • FIG. 7 shows the pressure curve in the injection system according to FIG. 1,
  • FIG. 8 plots the course of the injection quantity over time,
  • FIG. 9 shows a second exemplary embodiment of an injection system,
  • 10 shows the course of the control voltages of the valves used in the injection system according to FIG. 9,
  • FIG. 11 shows the stroke profile of the valves of the injection device according to FIGS. 9 and
  • Figure 12 shows the control pressure curve in the injection system.

Beschreibung der AusführungsbeispieleDescription of the embodiments

In Figur 1 der Zeichnung ist in halbschematischer Darstellung ein erstes Ausführungsbeispiel einer Kraftstoffeinspritzanlage für einen Verbrennungsmotor abgebildet. Diese Kraftstoffeinspritzanlage besteht im wesentlichen aus fünf Hauptteilen : einem Kraftstofftank 1, einer etwa als Kolbenpumpe ausgebildeten Kraftstofförderpumpe 2, einer Einspritzdüse 3, einer aus zwei Ventilen 4, 5 bestehenden Ventileinrichtung und einem elektronischen Steuergerät 6.In FIG. 1 of the drawing, a first exemplary embodiment of a fuel injection system for an internal combustion engine is shown in a semi-schematic representation. This fuel injection system essentially consists of five main parts: a fuel tank 1, a fuel delivery pump 2 designed approximately as a piston pump, an injection nozzle 3, a valve device consisting of two valves 4, 5 and an electronic control unit 6.

Dabei saugt die Pumpe 2 aus dem Tank 1 den Kraftstoff and und fördert ihn durch eine Zuführungsleitung 7 zur Zulaufbohrung 8 der Einspritzdüse 3. An die Zuführungsleitung 7 ist eine Überströmleitung 49 angeschlossen, die zu den Eingängen 9 und 10 der Ventile 4 und 5 führt.The pump 2 sucks the fuel from the tank 1 and delivers it through a feed line 7 to the inlet bore 8 of the injection nozzle 3. An overflow line 49 is connected to the feed line 7 and leads to the inlets 9 and 10 of the valves 4 and 5.

Die Einspritzdüse 3 verteilt und zerstäubt den Kraftstoff im Verbrennungsraum des Verbrennungsmotors. Die Einspritzdüse ist ein flüssigkeitsgesteuertes Nadelventil, dessen Ventilnadel 11 durch eine Feder 12 auf den Ventilsitz 13 gedrückt wird. Oberhalb der Düsenöffnung 14 liegt ein Ringraum 15, in den die Zulaufbohrung 8 einmündet. Die Ventilnadel wird durch den im Ringraum 15 herrschenden Druck von ihrem Sitz abgehoben, sobald die Druckkräfte die Kräfte der Feder 12 übersteigen.The injection nozzle 3 distributes and atomizes the fuel in the combustion chamber of the internal combustion engine. The injection nozzle is a liquid-controlled needle valve, the valve needle 11 of which is pressed onto the valve seat 13 by a spring 12. Above the nozzle opening 14 there is an annular space 15 into which the inlet bore 8 opens. The valve needle is lifted from its seat by the pressure prevailing in the annular space 15 as soon as the pressure forces exceed the forces of the spring 12.

Das elektrisch ansteuerbare Ventil 4 ist als Einzelheit in Figur 2 dargestellt. Es hat ein gehäuse 16, welches eine Ventilbohrung 17 aufweist. In der Ventilbohrung 17 ist dicht und gleitend ein kolbenartiges Ventilglied 18 geführt.The electrically controllable valve 4 is shown as a detail in FIG. 2. It has a housing 16 which has a valve bore 17. In the valve bore 17, a piston-like valve member 18 is tightly and slidably guided.

Der Eingang 10 wird von einer Bohrung gebildet, die einen größeren Durchmesser hat als die koaxial dazu verlaufende Ventilbohrung 17. Am Übergang von Einlaß 10 zur Ventilbohrung 17 ist eine hohlkegelförmige Sitzfläche 19 ausgebildet. Mit dieser Sitzfläche wirkt eine kegeiförmige Dichtfläche 20 zusammen, die an einem pilzförmigen Ansatz des Ventilglieds 18 angeordnet ist. Eine Druckfeder 21, die in der Ventilbohrung 17 angeordnet ist und sich einerseits auf der Dichtfläche 20 abgewandten Stirnfläche des Ventilglieds und andererseits an einem die Ausmündung der Ventilbohrung 17 verschließenden Stopfen 22 abstützt, hält das Ventil 4 in der in Figur 2 dargestellten offenen Stellung.The inlet 10 is formed by a bore which has a larger diameter than the valve bore 17 running coaxially therewith. At the transition from the inlet 10 to the valve bore 17 a hollow conical seat 19 is formed. A conical sealing surface 20 cooperates with this seat surface and is arranged on a mushroom-shaped extension of the valve member 18. A compression spring 21, which is arranged in the valve bore 17 and is supported on the one hand on the end face of the valve member facing away from the sealing surface 20 and on the other hand on a stopper 22 closing the mouth of the valve bore 17, holds the valve 4 in the open position shown in FIG.

An das Innere, dem Eingang 10 abgewandte Ende der Sitzfläche 19 anschließend ist koaxial zur Ventilbohrung 17 eine Ringkammer 23 angeordnet, in welche ein Ausgang 24 einmündet.An annular chamber 23, into which an outlet 24 opens, is arranged coaxially to the valve bore 17 at the inside of the end of the seat surface 19 facing away from the inlet 10.

Etwa auf der Mitte der axialen Länge des sich in der in Figur 2 dargestellten geöffneten Stellung befindlichen Ventilgliedes 18 mündet rechtwinklig zur Bewegungsrichtung des Ventilglieds 18 eine Führungsbohrung 25 ein, in der ein Klemmstempel 26 bewegleich angeordnet ist. Der Klemmstempel 26 ist ein Teil eines elektrisch ansteuerbaren Stellers 27.Approximately in the middle of the axial length of the valve member 18 in the open position shown in FIG. 2, a guide bore 25 opens at right angles to the direction of movement of the valve member 18, in which a clamping punch 26 is arranged so as to be movable. The clamping stamp 26 is part of an electrically controllable actuator 27.

Der Steller 27 besteht aus mehreren, zu einer Säule 28 geschichteten piezoelektrischen Scheiben 29, die in einem Isolierstoffgehäuse 30 angeordnet sind. Die piezoelektrischen Scheiben 29 sind elektrisch parallel geschaltet und können über Zuführungsleitungen 31, 32 an Gleichspannung gelegt werden. An seinem Fuß ist die Säule 28 an einem Deckel 33 befestigt, der eine Sachbohrung 34 im Gehäuse 16 verschließt. In dem Boden der Sackbohrung 34 mündet die Führungsbohrung 25 ein, in der sich der Klemmstempel 26 befindet.The actuator 27 consists of several, one Column 28 layered piezoelectric disks 29, which are arranged in an insulating housing 30. The piezoelectric disks 29 are electrically connected in parallel and can be connected to DC voltage via supply lines 31, 32. At its foot, the column 28 is attached to a cover 33 which closes a material bore 34 in the housing 16. The guide bore 25, in which the clamping punch 26 is located, opens into the bottom of the blind bore 34.

Im spannungsfreien Zustand des Stellers ist der Abstand zwischen der Außenfläche des Ventilglieds 18 und der leicht konkav ausgebildeten Stirnfläche des klemmstempels 26 nur wenige Tausendstel Millimeter groß. Wird nun an die Zuführungsleitung 31, 32 ein Gleichstrom angelegt, so dehnen sich die piezoelektrischen Scheiben 29 unter dem Einfluß des angelegten elektrischen Feldes bei gleichzeitiger Kontraktion ihrer Durchmesser in Richtung der Säulenachse so, daß der klemmstempel 26 in Richtung auf das Ventilglied 18 verschoben wird. Der Klemmstempel 26 kommt dabei an der Aussenfläche des Ventilglieds 18 zur Anlage und hält das Ventilglied 18 gegen die gegenüberliegende Wandung der ventilbohrung 17. Durch die hohe Klemmkraft wird das Ventilglied 18 mit der gegenüberliegenden Wandung der Ventilbohrung derart in kraftschlüssiger Berührung gehalten, daß eine Bewegung des Ventilglieds ausgeschlossen ist.In the tension-free state of the actuator, the distance between the outer surface of the valve member 18 and the slightly concave end face of the clamping plunger 26 is only a few thousandths of a millimeter. If a direct current is now applied to the feed line 31, 32, the piezoelectric disks 29 expand under the influence of the applied electric field and at the same time their diameters contract in the direction of the column axis such that the clamping plunger 26 is displaced in the direction of the valve member 18. The clamp 26 comes to rest on the outer surface of the valve member 18 and holds the valve member 18 against the opposite wall of the valve bore 17. Due to the high clamping force, the valve member 18 is held in frictional contact with the opposite wall of the valve bore such that a movement of the Valve member is excluded.

In der in Figur 2 der Zeichnung dargestellten Stellung liegt an den Zuführungsleitungen 31, 32 eine Gleichspannung an, wodurch der Klemmstempel das Ventilglied in der von der Sitzfläche 19 abgehobenen Stellung festklemmt. Ein vom Eingang 10 zum Ausgang 24 fließender Kraftstoffstrom baut an der von der Dichtfläche 20 mit der Sitzfläche 19 gebildeten Drosselstelle einen Druck auf, der das Ventil in nicht festgehlemmter Stellung zu schließen vermag. Erst bei Ab-, schaltung der am Steller 27 anliegenden Gleichspannung kann sich die Dirchtfläche 20 des Ventilglieds 18 auf die Sitzfläche 19 zu bewegen. Die Abschaltung der Steuerspannung erfolgt erst dann, wenn am Ventilglied der volle, erreichbare Drosseldruck P4 anliegt.In the position shown in FIG. 2 of the drawing, a direct voltage is applied to the supply lines 31, 32, as a result of which the clamping plunger clamps the valve member in the position raised from the seat surface 19. A fuel flow flowing from the inlet 10 to the outlet 24 builds up a pressure at the throttle point formed by the sealing surface 20 with the seat surface 19, which pressure can close the valve in the non-locked position. The direct surface 20 of the valve member 18 can only move onto the seat surface 19 when the DC voltage applied to the actuator 27 is switched off. The control voltage is only switched off when the full, achievable throttle pressure P4 is applied to the valve element.

Das in Figur 3 dargestellte. Ventil 5 ist ebenfalls elektrisch austeuerbar. Es hat wiederum ein Gehäuse 36, welches eine Ventilbohrung 37 aufweist. In der Ventilbohrung 37 ist wiederum dicht und gleitend ein kolbenartiges Ventilglied 38 geführt, welches eine kegelförmlge Dichtfläche 40 hat.The one shown in Figure 3. Valve 5 is also electrically controllable. It in turn has a housing 36 which has a valve bore 37. A piston-like valve member 38, which has a conical sealing surface 40, is in turn guided in the valve bore 37 in a sealed and sliding manner.

Die Dichtfläche arbeitet mit einer entsprechenden, hohlkegelförmigen Sitzfläche 39 zusammen. Die Sitzfläche ist am Übergang des Eingangs 9 in die koaxial angeordnete Ventilbohrung 37, die einen größeren Durchmesser als der Eingang 9 aufweist, angeordnet.The sealing surface works together with a corresponding, hollow-conical seat 39. The seat is arranged at the transition of the inlet 9 into the coaxially arranged valve bore 37, which has a larger diameter than the inlet 9.

An das innere, dem Eingang 9 abgewandte Ende der Sitzfläche 39 anschließend ist wieder koaxial zur Ventilbohrung 37 eine Ringkammer 43 angeordnet, in die ein Ausgang 44 des Ventils 5 einmündet.At the inner end of the seat surface 39 facing away from the inlet 9, an annular chamber 43 is arranged coaxially with the valve bore 37, into which an outlet 44 of the valve 5 opens.

Auf die der Dichtfläche 40 abgewandte Endfläche des Ventilglieds 18 stützt sich wiederum eine Druckfeder 41 ab, die mit ihrem anderen Ende an einen Stopfen 42 anliegt.On the end face of the valve member 18 facing away from the sealing surface 40, a compression spring 41 is supported, the other end of which rests on a stopper 42.

Etwa auf der Mitte der Axialerstreckung des an der Sitzfläche 39 anliegenden Ventilglieds 38 - so wie in Figur 3 gezeichnet - mündet wieder rechtwinklig zur Bewegungsrichtung des Ventilglieds eine Führungsbohrung 45 ein, in der ein Klemmstempel 46 beweglich angeordnet ist. Der Klemmstempel 46 ist wieder Teil eines elektrisch ansteuerbaren Stellers 47, der vollkommen dem elektrischen Steller 27 des Ventils gemäß Figur 2 entspricht. Auch an diesem Steiler 47 kann über Zuführungsleitungen 51, 52 eine Steuerspannung gelegt werden.Approximately in the middle of the axial extent of the valve member 38 abutting the seat 39 - as drawn in FIG. 3 - a guide bore 45 opens out again at right angles to the direction of movement of the valve member, in which a clamping plunger 46 is movably arranged. The clamping plunger 46 is again part of an electrically controllable actuator 47, which corresponds completely to the electrical actuator 27 of the valve according to FIG. 2. A control voltage can also be applied to this steeper 47 via supply lines 51, 52.

Die Ausgänge 24, 44 der die Ventileinrichtung der in Figur 1 dargestellten Kraftstoffeinspritzanlage bildenden Ventile 4, 5 sind an eine Rücklaufleitung 55 angeschlossen, welche zum Tank 1 zurückführtThe outputs 24, 44 of the valves 4, 5 forming the valve device of the fuel injection system shown in FIG. 1 are connected to a return line 55 which leads back to the tank 1

Die Zuführungsleitungen 31, 32 zum elektrischen Steller 27 des Ventils 4 und die Zuführungsleitungen 51, 52 zum Steller 47 des Ventils 5 sind mit dem schon erwähnten elektronischen Steuergerät 6 verbunden. Im Betrieb der Kraftstoffeinspritzanlage liefert das elektronische Steuergerät Steuerspannungen, die z. B. vom Saugrohrdruck, von der Motordrehzahl und von weiteren Korrekturgrößen abhängen. Die Einflußgröben werden am Motor durch mechanischelektrische Meßwandler erfaßt und dem Steuergerät in an sich bekannter Art und Weise als elektrische Größen eingegeben. Bei den Meßwandler handelt es sich etwa um Einspritzauslöser im Zündverteiler, um Druckfühler, um Temperaturfühler usw.The feed lines 31, 32 to the electrical actuator 27 of the valve 4 and the feed lines 51, 52 to the actuator 47 of the valve 5 are connected to the already mentioned electronic control unit 6. In the operation of the fuel injection system, the electronic control unit supplies control voltages which, for. B. depend on the intake manifold pressure, the engine speed and other correction variables. The influencing factors are detected on the engine by mechanical-electrical transducers and input to the control unit in a manner known per se as electrical quantities. The transducers are, for example, injection triggers in the distributor, pressure sensors, temperature sensors, etc.

Die Funktion der in Figur 1 der Zeichnung dargestellten Kraftstoffeinspritzanlage ist folgendermaßen : Handelt es sich bei der Pumpe 2 um eine etwa in Einspritzanlagenfür Dieselmotoren verwendete Kolbenpumpe, so wird sich der etwa in Figur 4 angedeutete Volumenstrom über die Zeit ergeben. Im Zeitpunkt t, beginnt der Fördervolumenstrom der Pumpe 2 anzusteigen. In diesem Zeitpunkt befinden sich die Ventilglieder 18, 38 der Ventile 4, 5 in der in Figur 1 dargestellten Stellung, in der - wie Figur 5 erkennen läßt - eine Steuerspannung an den Stellen 27 und 47 anliegt. Zum gleichen Zeitpunkt befindet sich das Ventilglied 18 des Ventils 4 in seiner maximalen Hubstellung (Kurve S4 in Figur 6). Das Ventilglied 38 des Ventils 5 befindet sich auf seinem Sitz 39, d. h. in der geschlossenen Stellung, was einer Hubstellung Null entspricht (Kurve s5 in Figur 6). Wie aus Figur 7 ersichtlich, herrscht in der Überströmleitung 49 in dem Zeitraum von Null bis t, zunächst ein Druck p0. Erst mit dem Beginn des Anstiegs des Volumenstroms im Zeitpunkt t, beginnt sich an der im Ventil 4 von der Dichtfläche 20 und der Sitzfläche 19 gebildeten Drosselstelle der Druck P4 aufzubauen. Dieser Druck P4 herrscht in der Überströmleitung 49 und in dem Ringraum 15 der Einspritzdüse 3. Im Zeitpunkt t2 wird schließlich vom elektronischen Steuergerät 6 die an den Leitungen 31, 32 des Stellers 27 anliegende Steuerspannung (U27 in Figur 5) abgeschaltet. Da hierdurch die klemmung aufgehoben wird, bewegt der am Ventilglied 18 des Ventils 4 angreifende Druck P4 das Ventilglied 18 in seine Schließstellung (Kurve S4 in Figur 6). Da jetzt die Überströmleitung 49 vom Rücklauf 55 zum Tank 1 abgeschlossen ist, steigt - wie im Druckverlauf aus Figur 7 abzulesen ist - der Druck sehr stark an. Da die Schaltzeit bei dem Ventil 4 in der Größenordnung von 10-s s liegt, ergibt sich eine nahezu senkrechte Flanke im Druckanstieg bis zum maximal erreichbaren Druck pmax. Dieser Pmax liegt oberhalb des Öffnungsdrucks p; der Einspritzdüse 3, weshalb die Ventilnadel 11 von ihrem Ventilsitz 13 abgehoben wird und der Kraftstoff durch die Düsenöffnung 14 in den Verbrennungsraum des Verbrennungsmotors gespritzt wird. Nach einem vom elektronischen Steuergerät 6 bestimmten Zeitraum - der Einspritzdauer - wird nun die an die Zuführungsleitungen 51, 52 des Stellers 47 anliegende Steuerspannung (U47 in Figur 5) im Zeitpunkt t3 abgeschaltet. Durch den in der Überströmleitung 49 und im Eingang 9 des Ventils 5 und damit am Ventilglied 38 des Ventils 5 anliegenden Druck wird nun das Ventilglied 38 von seiner Sitzfläche 39 abgehoben (Kurve s5 in Figur 6), wodurch die Überströmleitung 49 und letzlich der Ringraum 15 der Einspritzdüse 3 wieder mit der Rücklaufleitung 55 zum Tank 1 verbunden wird. Dadurch fällt - wie Figur 7 erkennen läßt - der Druck im Zeitpunkt t3 wieder auf den Wert po ab: Die Feder 12 der Einspritzdüse bewegt die Ventilnadel 11 wieder auf den Ventilsitz 13 ; die Einspritzdüse ist jetzt wieder geschlossen. Damit ist das in Figur 8 dargestellte Einspritzvolumen in den Verbrennungsraum des Motors gelangt. Schließlich hat der Kolben der Einspritzpumpe 2 seinen oberen Totpunkt erreicht, das im Zylinder der Pumpe 2 eingeschlossene Volumen ist ausgeschoben. Danach beginnt der beschriebene Vorgang von neuem.The function of the fuel injection system shown in FIG. 1 of the drawing is as follows: If the pump 2 is a piston pump, for example, used in injection systems for diesel engines, the volume flow indicated in FIG. 4 will result over time. At time t, the delivery volume flow of the pump 2 begins to increase. At this time, the valve members 18, 38 of the valves 4, 5 are in the position shown in FIG. 1, in which - as can be seen in FIG. 5 - a control voltage is present at the points 27 and 47. At the same time, the valve member 18 of the valve 4 is in its maximum stroke position (curve S4 in FIG. 6). The valve member 38 of the valve 5 is located on its seat 39, ie in the closed position, which corresponds to a zero stroke position (curve s 5 in FIG. 6). As can be seen from FIG. 7, there is initially a pressure p 0 in the overflow line 49 in the period from zero to t. Only when the volume flow begins to increase at time t does pressure P4 begin to build up at the throttle point formed in valve 4 by sealing surface 20 and seat surface 19. This pressure P4 prevails in the overflow line 49 and 3 in the annular space 15 of the injection nozzle in the time t 2 is finally from electronic control unit 6, the control voltage applied to the lines 31, 32 of the actuator 27 (U 27 in FIG. 5) is switched off. Since this removes the clamping, the pressure P 4 acting on the valve member 18 of the valve 4 moves the valve member 18 into its closed position (curve S4 in FIG. 6). Since the overflow line 49 from the return 55 to the tank 1 is now closed, the pressure rises very strongly, as can be seen in the pressure curve from FIG. Since the switching time for valve 4 is of the order of 10- s s, there is an almost vertical flank in the pressure rise up to the maximum achievable pressure p max . This P max is above the opening pressure p ; the injection nozzle 3, which is why the valve needle 11 is lifted from its valve seat 13 and the fuel is injected through the nozzle opening 14 into the combustion chamber of the internal combustion engine. After a period of time determined by the electronic control unit 6 - the injection duration - the control voltage applied to the supply lines 51, 52 of the actuator 47 (U 47 in FIG. 5) is then switched off at the time t 3 . Due to the pressure present in the overflow line 49 and in the inlet 9 of the valve 5 and thus on the valve member 38 of the valve 5, the valve member 38 is now lifted off its seat 39 (curve s 5 in FIG. 6), as a result of which the overflow line 49 and ultimately the annular space 15 of the injector 3 is connected again to the return line 55 to the tank 1. As a result, as can be seen in FIG. 7, the pressure drops again to the value p o at time t 3 : the spring 12 of the injection nozzle moves the valve needle 11 back onto the valve seat 13; the injector is now closed again. The injection volume shown in FIG. 8 has thus entered the combustion chamber of the engine. Finally, the piston of the injection pump 2 has reached its top dead center, the volume enclosed in the cylinder of the pump 2 has been pushed out. Then the described process begins again.

Näturlich ist es prinzipiell auch möglich, die Pumpe 2 als kontinuierlich fördernde Pumpe auszugestalten ; ebenso wäre auch ein Betrieb aus einen Speicher denkbar.In principle, it is of course also possible to design the pump 2 as a continuously delivering pump; operation from a memory would also be conceivable.

Das in Figur 9 der Zeichnung dargestellte zweite Ausführungsbeispiel einer Kraftstoffeinspritzanlage für einen Verbrennungsmotor ist dagegen mit einer kontinuierlich fördernden Pumpe 62 ausgerüstet. Auch diese Kraftstoffeinspritzanlage besteht wieder aus einem Kraftstofftank 61, der Pumpe 62, einer Einspritzdüse 63. einer aus zwei Ventilen 64, 65 bestehenden Ventileinrichtung und einem elektronischen Steuergerät 66. Die Pumpe 62 fördert den aus dem Tank 61 angesaugten Kraftstoff in einer Speicher 60. Der Speicher 60 wiederum ist über eine Zuführungsleitung 67 einerseits mit der Zulaufbohrung 68 der Einspritzdüse 63 und andererseits mit dem Eingang 69 des Ventils 65 verbunden.In contrast, the second exemplary embodiment of a fuel injection system for an internal combustion engine shown in FIG. 9 of the drawing is equipped with a continuously delivering pump 62. This fuel injection system also consists again of a fuel tank 61, the pump 62, an injection nozzle 63. a valve device consisting of two valves 64, 65 and an electronic control unit 66. The pump 62 conveys the fuel drawn from the tank 61 into a reservoir 60 The reservoir 60 is in turn connected via a feed line 67 on the one hand to the inlet bore 68 of the injection nozzle 63 and on the other hand to the inlet 69 of the valve 65.

Auch die Einspritzdüse 63 ist ein flüssigkeitsgesteuertes Nadelventil, dessen Ventilnadel 71 durch aen aut aie Huckseite eines mit aer Nadel 71 verbundenen Steuerkolbens 72 wirkenden Steuerdrucks auf dem Ventilsitz 73 gehalten wird. Oberhalb der Düsenöffnung 74 liegt wieder ein Ringraum 75, in den die Zulaufbohrung 68 eimündet. Die Ventilnadel 71 wird durch den wegen des Speichervolumens 60 im wesentlichen stets gleichen, im Ringraum 75 herrschenden Druck , von ihrem Sitz abgehoben, sobald die vom Steuerdruck auf den Steuerkolben 72 ausgeübten Kräfte unter die vom im Ringraum 75 auf die Ventilnadel 11 ausgeübten, vom Speicherdruck herrührenden kräfte fallen.The injection nozzle 63 is also a liquid-controlled needle valve, the valve needle 71 of which is held on the valve seat 73 by aen aut aie the rear side of a control pressure 72 which is connected to the needle 71. An annular space 75, into which the inlet bore 68 opens, is again located above the nozzle opening 74. The valve needle 71 is lifted from its seat due to the essentially constant pressure prevailing in the annular space 75 because of the storage volume 60 as soon as the forces exerted by the control pressure on the control piston 72 fall below the forces exerted on the valve needle 11 in the annular space 75 by the storage pressure resulting forces fall.

Das elektrisch ansteuerbare Ventil 64 entspricht vollkommen dem in Figur 3 dargestellten Ventil. Das elektrisch ansteuerbare Ventil 65 entspricht ebenfalls bis auf eine unten näher ausgeführte Abänderung dem in Figur 3 dargestellten Ventil. In der nachfolgenden Beschreibung werden deshalb - so weit eine Übereinstimmung vorliegt - die in Figur 3 verwendeten Bezugszahlen benutzt werden.The electrically controllable valve 64 corresponds completely to the valve shown in FIG. 3. The electrically controllable valve 65 also corresponds to the valve shown in FIG. 3 except for a modification which is explained in more detail below. The reference numbers used in FIG. 3 are therefore used in the following description, insofar as there is agreement.

Die Zulaufbohrung 69 des Ventils 65 ist - wie oben erwähnt - mit dem Speicher 60 verbunden. Natürlich könnte die Zulaufbohrung 69 mit einer anderen, vom Speicher 60 unabhängigen Druckquelle verbunden sein. Der Ausgang 84 des Ventils 65 ist mit einer Steuerleitung 89 verbunden, die in den Raum der Einspritzdüse 63 mündet, in der sich der Kolben 72 befindet. Die Rückseite des Ventilglieds 38' des Ventils 65 ist über eine einstellbare Drossel 85 druckausgeglichen. (Bei dem in Figur 3 dargestellten Ventil muß zu diesem Zweck lediglich der Stopfen 42 eine koaxiale Bohrung aufweisen, über die die Ventilbohrung 37 über die Drossel 85 mit dem Ausgang 84 verbunden werden kann).As mentioned above, the inlet bore 69 of the valve 65 is connected to the accumulator 60. Of course, the inlet bore 69 could be connected to another pressure source that is independent of the reservoir 60. The outlet 84 of the valve 65 is connected to a control line 89 which opens into the space of the injection nozzle 63 in which the piston 72 is located. The back of the valve member 38 'of the valve 65 is pressure balanced via an adjustable throttle 85. (For the purpose of the valve shown in FIG. 3, only the plug 42 has to have a coaxial bore, via which the valve bore 37 can be connected to the outlet 84 via the throttle 85).

Über Zuführungsleitungen 51', 52' ist der Steller 47', der einen Klemmstempel 46' aufweist mit dem elektronischen Steuergerät 66 verbunden.The actuator 47 ', which has a clamp 46', is connected to the electronic control device 66 via supply lines 51 ', 52'.

Die Steuerleitung 89 ist wiederum mit dem Eingang 70 des Ventils 64 verbunden. Das Ventil 64 entspricht vollkommen dem in Figur 3 beschriebenen Ausführungsbeispiel. Der Ausgang 94 des Ventils 64 ist über eine Rücklaufleitung 95 mit dem Tank verbunden.The control line 89 is in turn connected to the input 70 of the valve 64. The valve 64 corresponds completely to the embodiment described in FIG. 3. The outlet 94 of the valve 64 is connected to the tank via a return line 95.

Auch das Ventil 64 weist einen elektrisch ansteuerbaren Steller 47" mit einem Klemmstempel 46" auf, der das Ventilglied 38" ebenso wie beim Ventil 65 in seiner Schließstellung festklemmen kann. Der elektrische Steller 47" ist auch über Zuführungsleitungen 51", 52" mit dem elektronischen Steuergerät 66 verbunden.The valve 64 also has an electrically controllable actuator 47 "with a clamping plunger 46" which, like the valve 65, can clamp the valve member 38 "in its closed position. The electrical actuator 47" is also connected to the via supply lines 51 ", 52" electronic control unit 66 connected.

Die Funktion der in Figur 9 dargestellten Kraftstoffeinspritzanlage ist folgendermaßen : Es sei angenommen, daß in der in Figur 9 dargestellten Betriebsstellung in der Steuerleitung 89 im Zeitpunkt Null ps herrscht (Figur 12). Der Druck ps beträgt beispielsweise etwa 200 bar. Die Ventilglieder 38' ; des Ventils 65 und 38" des Ventils 64 sind - da an den Stellern 47', 47". eine Steuerspannung U65 und Ue4 (Figur 10) anliegt - in ihrer Schließstellung festgeklemmt (Kurven s64 und s65 in Figur 11). Da die wirksame Fläche des Steuerkolbens 72 größer ist als die hydraulisch wirksame Fläche der Ventilnadel 71 im Ringraum 75 wird die Ventilnadel 71 auf den Sitz 73 gehalten. Wenn im Zeitpunkt t, elektronische Steuergeräte 66 die am Steller 47" des Ventils 64 anliegende Steuerspannung (U65 in Figur 10) abschaltet, wird unter der Wirkung des in der Steuerleitung 89 herrschenden Druckes ps das Ventilglied 38" sehr schnell von seinem Sitz abgehoben. Da die Druckkraft bereits voll aufgebaut ist, wenn die vom Steller 47" ausgeübte Klemmkraft aufgehoben wird, wird auch bei diesem Ventil eine sehr steile Schaltflanke von etwa 100 Mikrosekunden erzielt. Da nun die Steuerleitung 89 über die Rücklaufleitung 95 mit dem Tank 61 verbunden ist, fällt der Druck in der Steuerleitung 89 auf den Wert po ab. Da nun die auf den Steuerkolben 72 wirkende Schließkraft entfällt, wird die Ventilnadel 71 von dem im Ringraum 75 herrschenden Druck abgehoben und der Kraftstoff kann durch die geöffnete Düsenöffnung 74 in den Brennraum des Verbrennungsmotors gelangen.The function of the fuel injection system shown in FIG. 9 is as follows: It is assumed that in the operating position shown in FIG. 9 there is zero p s in the control line 89 at the time (FIG. 12). The pressure p s is, for example, approximately 200 bar. The valve members 38 '; of the valve 65 and 38 "of the valve 64 are - since at the actuators 47 ', 47". a control voltage U 65 and U e4 (FIG. 10) is present - clamped in its closed position (curves s 64 and s 65 in FIG. 11). Because the effective area of the control piston 72 is larger than the hydraulically effective area of the valve needle 71 in the annular space 75, the valve needle 71 is held on the seat 73. If, at time t, electronic control devices 66 switch off the control voltage present at actuator 47 "of valve 64 (U 65 in FIG. 10), valve member 38" is very quickly lifted off its seat under the effect of pressure p s prevailing in control line 89 . Since the pressure force is already fully built up when the clamping force exerted by the actuator 47 "is released, a very steep switching edge of approximately 100 microseconds is also achieved with this valve. Since the control line 89 is now connected to the tank 61 via the return line 95, The pressure in the control line 89 drops to the value p o . Since the closing force acting on the control piston 72 is no longer present, the valve needle 71 is lifted from the pressure prevailing in the annular space 75 and the fuel can flow through the open nozzle opening 74 into the combustion chamber of the Coming to the internal combustion engine.

Unter der Kraft der Feder 41" wird nun das Ventilglied 38" des Ventils 64 wieder auf seinen Sitz zurückgedrückt, wonach im Zeitpunkt t2 das Steuergerät 66 wieder eine Steuerspannung an den Steiler 47" anliegt. Dadurch wird vom Klemmstempel 46" das Ventilglied 38" in der Ventilbohrung 37" in seiner Schließstellung festgeklemmt.Under the force of the spring 41 ", the valve member 38" of the valve 64 is now pushed back into its seat, after which the control device 66 is again at the control unit 66 at the time t 2 , a control voltage is applied to the stepper 47 ". clamped in the valve bore 37 "in its closed position.

Im Zeitpunkt t3 (Figur 10) schaltet nun das elektronische Steuergerät 66 die am Steller 47' des Ventils 65 anliegende Steuerspannung ab. Unter der Wirkung des in der Steuerleilung 77 und am Eingang 69 des Ventils 65 herrschenden Druckes wird nun das Ventilglied 38' gegen die Kraft der Feder 41' von seinem Sitz abgehoben. Hierdurch baut sich jetzt in der Steuerleitung 89 wieder der Steuerdruck Ps (Figur 12) auf. Infolge der auf den Stellkolben 72 wirkenden Stellkraft wird nun die Ventilnadel 71 wieder auf ihren Sitz 73 gedrückt. Damit ist das Ende des Zeitraumes,- in dem der Kraftstoff von der Einspritzdüse 63 in den Brennraum gelangen konnte - die Einspritzdauer t3-tl -, erreicht.At time t 3 (FIG. 10), the electronic control unit 66 now switches off the control voltage present at the actuator 47 'of the valve 65. Under the effect of the pressure prevailing in the control line 77 and at the inlet 69 of the valve 65, the valve member 38 'is now lifted from its seat against the force of the spring 41'. As a result, the control pressure Ps (FIG. 12) now builds up again in the control line 89. As a result of the actuating force acting on the actuating piston 72, the valve needle 71 is now pressed back onto its seat 73. The end of the period in which the fuel was able to get into the combustion chamber from the injection nozzle 63 has thus reached the injection duration t 3 -t l -.

Da inzwischen über die einstellbare Drossel 85 die Rückseite des Ventilglieds 38' des Ventils 65 druckentlastet worden ist, kann die Feder 41' das Ventilglied 38' wieder in die Schließstellung bewegen. Damit beginnt der beschriebene Vorgang von neuem.Since the rear of the valve member 38 'of the valve 65 has now been relieved of pressure via the adjustable throttle 85, the spring 41' can move the valve member 38 'back into the closed position. The process described begins anew.

Claims (12)

1. Fuel injection equipment for a combustion engine, preferably a diesel engine, comprising a fuel injection pump or a pressure accumulator for delivering fuel to an ejection nozzle and comprising two electrically controlled valves operating in anti-parallel each of which controls an opening leading to a low pressure line and in so doing determines the start of the injection and the end of the injection, characterised in that, the valves (4, 5, 64, 65) operating in anti-parallel, the first (4, 64) of which determines the start of the injection and the second (5, 65) determines the end of the injection and each of which has a spring-loaded valve member actuable by the pressure of the fuel to be controlled each valve being prevented from moving, through clamping on switching-in or switching-off a control voltage, by an electrical regulator (27, 47, 47', 47") the regulating movement of which has at least one component which extends perpendicular to the direction of movement of the valve member.
2. Fuel injection equipment according to claim 1, characterised in that, the regulator (27, 47, 47', 47") is a laminated column (28) of piezo-electric discs the axis of the column being arranged at least substantially perpendicular to the axis of movement of the valve member (18, 38, 38', 38") actuable by the pressure of the fuel.
3. Fuel injection equipment according to claim 1 or 2, characterised in that, an overflow line (49) which is connected to the supply line (7) leading from the pump (2), formed particularly as a piston pump, to the injection nozzle (3), is connectible alternately to a return line (55) to the tank (1) through the valves (4, 5) of the valve arrangement.
4. Fuel injection equipment according to claim 3, characterised in that, the valve member of the second valve (5) can be raised from its seat (39) out of its closed position in which it can be clamped by the regulator (47), by the force of the fuel against the force of the spring (41).
5. Fuel injection equipment according to claim 3, characterised in that, the first valve (4) is movable out of the open position, in which it can be clamped by the regulator (27), on to its seat (19) by the pressure of the fuel against the force of the spring (21).
6. Fuel injection equipment according to claim 3 or 5, characterised in that, the valve member (18) has a conical sealing surface (20) converging in the direction of closing movement of the valve member (18) and arranged on an umbrella-like extension which sealing surface is raised from its seating surface (19) by the spring (21) and that the valve member (18) can be clamped in that position.
7. Fuel injection equipment according to claim 6, characterised in that, in the open position of the valve (4), the sealing surface (20) of the valve member (18) forms, together with its seating surface (19), a throttle location and that the pressure built up at the said throttle location attempts to close the valve (4).
8. Fuel injection equipment according to claim 1 or 2, characterised in that, a control line (89) leading to the rear of a valve needle (71) of the injection nozzle (63) can be connected to a return line (95) to the tank (61) or to a control pressure line (77) through the valves (64, 65) of the valve arrangement.
9. Fuel injection equipment according to claim 8, characterised in that, the control pressure line (77) is connected to the pump (62) connected especially to a pressure accumulator (60) and preferably formed as a distributor injection pump.
10. Fuel injection equipment according to claim 8, characterised in that, the valve member (38', 38") of each valve (64, 65) can be raised from its seat by the pressure of the fuel against the force of the spring (41', 41") out of its closed position in which it can be clamped by the regulator (47, 47").
11. Fuel injection equipment according to claim 10, characterised in that, the second valve (65) is pressure balanced by the influence of pressure on the rear of the valve member (38') through a throttle (85) which is particularly adjustable.
12. Fuel injection equipment according to claim 3 or 8, characterised in that, the valve needle (71) of the injection nozzle (63) is actuable by the pressure prevailing in a supply line (67), especially against the force of a spring.
EP81105545A 1980-10-23 1981-07-15 Fuel injection system Expired EP0050710B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3039967 1980-10-23
DE19803039967 DE3039967A1 (en) 1980-10-23 1980-10-23 FUEL INJECTION SYSTEM

Publications (2)

Publication Number Publication Date
EP0050710A1 EP0050710A1 (en) 1982-05-05
EP0050710B1 true EP0050710B1 (en) 1984-04-11

Family

ID=6114997

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81105545A Expired EP0050710B1 (en) 1980-10-23 1981-07-15 Fuel injection system

Country Status (4)

Country Link
US (1) US4388908A (en)
EP (1) EP0050710B1 (en)
JP (1) JPS5799266A (en)
DE (2) DE3039967A1 (en)

Families Citing this family (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3148671A1 (en) * 1981-12-09 1983-07-21 Robert Bosch Gmbh, 7000 Stuttgart FUEL INJECTION DEVICE FOR INTERNAL COMBUSTION ENGINES, ESPECIALLY FOR DIESEL ENGINES
DE3237258C1 (en) * 1982-10-08 1983-12-22 Daimler-Benz Ag, 7000 Stuttgart Electrically pilot operated valve arrangement
US4550744A (en) * 1982-11-16 1985-11-05 Nippon Soken, Inc. Piezoelectric hydraulic control valve
DE3302293A1 (en) * 1983-01-25 1984-07-26 Klöckner-Humboldt-Deutz AG, 5000 Köln FUEL INJECTION DEVICE FOR INTERNAL COMBUSTION ENGINES
FR2541379B1 (en) * 1983-02-21 1987-06-12 Renault IMPROVEMENT IN ELECTROMAGNETICALLY CONTROLLED INJECTION SYSTEMS FOR A PRESSURE-TIME DIESEL ENGINE WHERE THE INJECTOR NEEDLE IS DRIVEN BY THE DISCHARGE THEN LOADING A CAPACITY
US4667638A (en) * 1984-04-17 1987-05-26 Nippon Soken, Inc. Fuel injection apparatus for internal combustion engine
US4643155A (en) * 1984-10-05 1987-02-17 Olin Corporation Variable stroke, electronically controlled fuel injection control system
US4748949A (en) * 1985-02-05 1988-06-07 Sulzer Brothers Limited Method and system for injecting a pilot fuel into a combustion chamber
DE3504265A1 (en) * 1985-02-08 1986-08-14 M.A.N.-B & W Diesel GmbH, 8900 Augsburg FUEL HIGH PRESSURE INJECTION DEVICE ON INTERNAL COMBUSTION ENGINES
JPH0286953A (en) * 1988-09-21 1990-03-27 Kanesaka Gijutsu Kenkyusho:Kk Fuel injection valve
DE19836902A1 (en) * 1998-08-14 2000-02-17 Bosch Gmbh Robert Internal combustion motor valve control has a mounting for the valve in the valve guide with an electric operation for shorter valve control response times
DE19950762A1 (en) * 1999-10-21 2001-04-26 Bosch Gmbh Robert Fuel injection valve has actuating body or valve needle connected to valve actuator via at least one stop actuator acting essentially perpendicular to valve actuator direction
US6836056B2 (en) 2000-02-04 2004-12-28 Viking Technologies, L.C. Linear motor having piezo actuators
WO2001067431A1 (en) 2000-03-07 2001-09-13 Viking Technologies, Inc. Method and system for automatically tuning a stringed instrument
US6548938B2 (en) 2000-04-18 2003-04-15 Viking Technologies, L.C. Apparatus having a pair of opposing surfaces driven by a piezoelectric actuator
US6717332B2 (en) 2000-04-18 2004-04-06 Viking Technologies, L.C. Apparatus having a support structure and actuator
US6759790B1 (en) 2001-01-29 2004-07-06 Viking Technologies, L.C. Apparatus for moving folded-back arms having a pair of opposing surfaces in response to an electrical activation
US6879087B2 (en) 2002-02-06 2005-04-12 Viking Technologies, L.C. Apparatus for moving a pair of opposing surfaces in response to an electrical activation
CA2488481C (en) * 2002-06-21 2011-09-06 Viking Technologies, L.C. Uni-body piezoelectric motor
JP4791957B2 (en) 2003-04-04 2011-10-12 バイキング テクノロジィーズ エル．シー． Equipment and methods for optimizing work from functional material actuator products
JP4847564B2 (en) 2009-07-22 2011-12-28 日本航空電子工業株式会社 Connector assembly

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1644769A (en) * 1920-11-02 1927-10-11 Falk Corp Fuel-injection system for oil engines
US2287702A (en) * 1941-05-15 1942-06-23 American Locomotive Co Fuel injection device
DE1917927A1 (en) * 1969-04-09 1970-10-29 Bosch Gmbh Robert Fuel injection pump for internal combustion engines
US3851635A (en) * 1969-05-14 1974-12-03 F Murtin Electronically controlled fuel-supply system for compression-ignition engine
DD103691A1 (en) * 1973-04-06 1974-02-05
GB1543714A (en) * 1975-03-07 1979-04-04 Lucas Cav Ltd Fuel injection pumping apparatus
DE2551463A1 (en) * 1975-11-15 1977-05-18 Maschf Augsburg Nuernberg Ag FUEL INJECTION DEVICE FOR COMBUSTION MACHINERY
JPS5918547B2 (en) * 1977-12-03 1984-04-27 三菱重工業株式会社 Accumulator fuel injection device
WO1981000283A1 (en) * 1979-07-16 1981-02-05 Caterpillar Tractor Co Electrically controlled fuel injection apparatus

Also Published As

Publication number Publication date
JPS5799266A (en) 1982-06-19
EP0050710A1 (en) 1982-05-05
US4388908A (en) 1983-06-21
DE3163073D1 (en) 1984-05-17
DE3039967A1 (en) 1982-06-03

Similar Documents

Publication Publication Date Title
EP0050710B1 (en) Fuel injection system
EP0925440B1 (en) Fuel injector
EP0657642B1 (en) Fuel injection device for internal combustion engines
DE19640826B4 (en) Storage fuel injection device and pressure control device therefor
EP0779949B1 (en) Fuel injection device for internal combustion engines
EP0954695B1 (en) Dual nozzle for injecting fuel and an additional fluid
EP0657644B1 (en) Fuel injection device for internal combustion engines
EP0908617B1 (en) Fuel injection apparatus
DE4313852A1 (en) Fuel injection device for internal combustion engines
DE19732802A1 (en) Fuel injection device for internal combustion engines
DE10210282A1 (en) Device for injecting fuel into stationary internal combustion engines
DE4332119A1 (en) Fuel injection device for internal combustion engines
EP0900332A1 (en) Valve for controlling fluids
EP0147591A2 (en) Delivery valve for fuel injection pumps
EP0205882B1 (en) Fuel injection device
DE4341545A1 (en) Fuel injection device for internal combustion engines
WO1999018349A1 (en) Directly controlled injection valve, especially a fuel injection valve
DE3715614A1 (en) FUEL INJECTION PUMP
DE2833431A1 (en) FUEL INJECTION NOZZLE
WO2001011219A1 (en) Common rail injector
DE3236828A1 (en) FUEL INJECTION DEVICE
AT397129B (en) FUEL INJECTION NOZZLE
DE19848904A1 (en) Pressure stage for regulating internal combustion engine, preferably diesel engine, pre-injection fuel has control piston that can be separated from pressure regulator for producing higher pressure
DE3511492A1 (en) Fuel injection device for internal combustion engines
DE4030890A1 (en) Fuel injector for two=stroke IC engine - includes mixing chamber with piston valve controlled by pressure of fuel introduced into hot exhaust gas

Legal Events

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

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19810715

AK Designated contracting states

Designated state(s): DE FR GB

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): DE FR GB

REF Corresponds to:

Ref document number: 3163073

Country of ref document: DE

Date of ref document: 19840517

ET Fr: translation filed
PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

26 Opposition filed

Opponent name: M.A.N. - B&W DIESEL GMBH

Effective date: 19841218

PLAB Opposition data, opponent's data or that of the opponent's representative modified

Free format text: ORIGINAL CODE: 0009299OPPO

R26 Opposition filed (corrected)

Opponent name: MAN B&W DIESEL AKTIENGESELLSCHAFT

Effective date: 19841218

PLBN Opposition rejected

Free format text: ORIGINAL CODE: 0009273

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

Free format text: STATUS: OPPOSITION REJECTED

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

Ref country code: GB

Payment date: 19900709

Year of fee payment: 10

27O Opposition rejected

Effective date: 19900414

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

Ref country code: FR

Payment date: 19900730

Year of fee payment: 10

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

Ref country code: DE

Payment date: 19900921

Year of fee payment: 10

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

Ref country code: GB

Effective date: 19910715

GBPC Gb: european patent ceased through non-payment of renewal fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19920331

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

Ref country code: DE

Effective date: 19920401

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

APAH Appeal reference modified

Free format text: ORIGINAL CODE: EPIDOSCREFNO