EP0240686B1 - Fuel injection pump for internal-combustion engines with exhaust gas recirculation - Google Patents

Fuel injection pump for internal-combustion engines with exhaust gas recirculation Download PDF

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Publication number
EP0240686B1
EP0240686B1 EP87102705A EP87102705A EP0240686B1 EP 0240686 B1 EP0240686 B1 EP 0240686B1 EP 87102705 A EP87102705 A EP 87102705A EP 87102705 A EP87102705 A EP 87102705A EP 0240686 B1 EP0240686 B1 EP 0240686B1
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EP
European Patent Office
Prior art keywords
fuel injection
outlet
channel
injection pump
pump
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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EP87102705A
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German (de)
French (fr)
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EP0240686A1 (en
Inventor
Karl Konrath
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Robert Bosch GmbH
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Robert Bosch GmbH
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    • 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
    • F02M41/00—Fuel-injection apparatus with two or more injectors fed from a common pressure-source sequentially by means of a distributor
    • F02M41/08—Fuel-injection apparatus with two or more injectors fed from a common pressure-source sequentially by means of a distributor the distributor and pumping elements being combined
    • F02M41/10—Fuel-injection apparatus with two or more injectors fed from a common pressure-source sequentially by means of a distributor the distributor and pumping elements being combined pump pistons acting as the distributor
    • F02M41/12—Fuel-injection apparatus with two or more injectors fed from a common pressure-source sequentially by means of a distributor the distributor and pumping elements being combined pump pistons acting as the distributor the pistons rotating to act as the distributor
    • F02M41/123—Fuel-injection apparatus with two or more injectors fed from a common pressure-source sequentially by means of a distributor the distributor and pumping elements being combined pump pistons acting as the distributor the pistons rotating to act as the distributor characterised by means for varying fuel delivery or injection timing
    • F02M41/125—Variably-timed valves controlling fuel passages
    • F02M41/126—Variably-timed valves controlling fuel passages valves being mechanically or electrically adjustable sleeves slidably mounted on rotary piston
    • 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
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/52—Systems for actuating EGR valves
    • F02M26/59—Systems for actuating EGR valves using positive pressure actuators; Check valves therefor
    • F02M26/62—Systems for actuating EGR valves using positive pressure actuators; Check valves therefor in response to fuel pressure

Definitions

  • the invention is based on a fuel injection pump for internal combustion engines with exhaust gas recirculation according to the preamble of claim 1.
  • a centrifugal adjuster is provided which is adjustable depending on the preload of a control spring against which the centrifugal adjuster works as a speed sensor.
  • the adjustment of the control spring is entered arbitrarily as a torque request or as a load signal.
  • the centrifugal adjuster opens a connection channel between a fuel-filled interior with a predetermined pressure level and a relief chamber, such that the amount flowing off is at least partly a measure of the load.
  • the outflowing fuel is throttled at a throttle and thus a control pressure is generated upstream of the throttle, which in turn is to be load-dependent and now acts on a hydraulically actuatable control element by means of which a circuit can be closed.
  • a switching valve which controls an actuating medium to an exhaust gas recirculation valve motor.
  • a fuel injection pump the pump piston of which contains a second channel, but this second channel connects an annular groove provided in the control slide valve on the pump piston side, one boundary edge of which is designed as the control edge controlling the relief channel, with one the annular groove surrounding the pump carbons in the area of the cylinder, which is in turn connected to a fuel inlet of the pump work space.
  • the second channel serves to supply the fuel quantity flowing out of the working space after the high-pressure injection has ended again to the suction side of the fuel injection pump, specifically into a memory which is decoupled from a controlled suction throttle via a check valve opening towards the pump working space .
  • Such a device is intended to achieve an exact metering of the fuel quantity which is controlled as a function of the air flow and is to be injected. This is done via the controlled suction throttle and the inclusion of the scrapped residual amount in the filling of the pump work space per filling cycle of the fuel injection pump.
  • the fuel injection pump according to the invention with the characterizing features of claim 1 has the advantage that for controlling the exhaust gas recirculation valve, the position of the control slide, which is directly decisive for the metering of the injection quantity required for the respective load condition, is used as a measure of the operating load of the internal combustion engine. Another advantage is that, apart from determining the distance of the outlet of the relief channel from the inlet of the other channel in the pump piston, no adjustment or assignment work is required. Another advantage is that the speed-dependent delivery pressure of a delivery pump, which also prevails in the suction chamber of the injection pump receiving the control slide, is used to convert the position of the control slide into an electrical signal.
  • a cylinder liner 3 is inserted, in the cylinder 2 of which a pump piston 4 is displaceable, which is set into a reciprocating and at the same time rotating movement by a drive (not shown).
  • the pump piston 4 closes off one end of a pump working chamber 5 and protrudes with its other end out of the cylinder liner 3 into a suction chamber 7 of the housing 1. At this end the pump piston 4 is connected to the drive (not shown in more detail).
  • the pump working chamber 5 is supplied with fuel from the pump suction chamber 7 via longitudinal grooves 8 arranged in the lateral surface of the pump piston 4 and a suction bore 9 running through the cylinder liner 3 and the housing 1, as long as the pump piston 4 executes its suction stroke or its lower one shown in FIG. 1 Dead center position occupies.
  • a feed pump 10 feeds fuel from a fuel reservoir 11 into the suction space 7 of the housing 1 as the pressure increases as a function of the speed.
  • a pressure control valve 12 connected in parallel with the feed pump 10 controls the pressure in the pump suction space 7 in a known manner as a function of the speed.
  • a radial bore 16 branches off from this relief channel 15 and leads to a distributor groove 17 in the lateral surface of the pump piston 4.
  • a plurality of delivery lines 18 branch off in a radial plane of the cylinder 2 and are arranged distributed uniformly on the circumference of the cylinder 2 in accordance with the number of cylinders of the assigned internal combustion engine to be supplied with fuel.
  • the delivery lines 18 lead to the fuel injection points, not shown, of the internal combustion engine.
  • a radial bore 20 branches off from the relief channel 15 and forms an outlet A in the outer surface of the pump piston 4.
  • an annular regulating slide 21 is displaceably arranged on the pump piston 4 as a quantity adjusting member, the end face of which facing the cylinder liner 3 forms a control edge 22 for the outlet A.
  • the control slide 21 is from a control device, not shown, due to several operating parameters, such as desired speed, speed, air pressure, temperature and. Like. Axially adjusted to the pump piston 4 via a control lever 23.
  • control slide 21 assumes a position shown in the figure, in which, in the bottom dead center position of the pump piston 4, the distance between the outlet A of the relief channel 15 and the control edge 22 of the control slide 21 has the dimension s v .
  • the control slide 21 is adjusted to the left with reference to the drawing, so that the distance between the outlet A and the control edge 22 is reduced.
  • the useful stroke available in each case, which the pump piston 4 or the outlet A must travel from the bottom dead center of the pump piston 4, is thereby changed.
  • the position of the control edge 22 of the control slide 21 is therefore decisive for the respective size of the injection quantity in a specific load range of the internal combustion engine.
  • the pump piston 4 there is also a second channel 25, from which a radial bore 26 with an outlet B branches off in the area of the pump piston section which is always in the cylinder 2, and a radial bore 27 with an inlet E branches off in the effective range of the control slide 21.
  • the inlet E of the channel 25 to the control edge 22 of the control slide 21 has a distance SL which is greater than the distance Sv of the outlet A of the relief channel 15 from the control edge 22, so that the inlet E of the channel 25 to the outlet A of the relief channel 15 is offset by a certain distance.
  • the channel 25 is only opened during the stroke of the pump piston 4 after the outlet A of the relief bore 15 has already been opened.
  • the control slide 21 is adjusted to its rightmost position (drawing)
  • the inlet E of the channel 25 is not opened at all during the pressure stroke of the pump piston 4.
  • the inlet E is released by the control slide 21 towards the end of the pressure stroke of the pump piston 4 when the control slide assumes a position in the partial load range which is to the left of the position shown in the drawing and in which the outlet A of the relief bore 15 is already opened during the pump piston stroke is when the inlet E of the channel 25 reaches the control edge 22 of the control slide 21.
  • annular groove 28 is arranged in the cylinder liner 3, which is connected via a radial bore 29 in the cylinder liner 3 and a bore 30 to a blind bore 31.
  • a bore 32 branches off from the blind bore 31 to an outflow throttle 33, from which a line 34 leads to the unpressurized fuel reservoir 11.
  • a pressure switch 35 known per se is screwed into the blind bore 31 and closes an electrical contact 37 at a pressure which is in the range of the delivery pressure prevailing in the suction chamber 7 and thus generates an electrical signal for controlling an exhaust gas recirculation valve of the internal combustion engine.
  • the application of fuel to the pressure switch 35 from the suction space 7 and the pressure prevailing there is controlled as a function of the position of the control slide 21.
  • the inlet of the channel 25, which is connected to the pressure switch 35 via the annular groove 28 and the bores 29 and 30, is not opened when the control slide 21 is in the fully loaded position during the remaining stroke of the pump piston 4 after opening A has been opened, so that the pressure-relieved via the outflow throttle 33 blind bore 31 and thus the pressure switch 35 are depressurized.
  • the inlet E of the channel 25 is opened towards the end of the pressure stroke of the pump piston 4, so that the pressure in the suction space 7 through the channel 25 and the bores 29, 30 can act on the pressure switch 35.
  • the contact 37 of the pressure switch 35 is closed, so that an electrical control signal is generated that can be used directly to open the exhaust gas recirculation valve of the internal combustion engine or serves as a control signal.
  • a Throttle 36 can be arranged in the radial bore 29 in the cylinder liner 3.
  • a pressure-sensitive sensor element can be arranged instead of the pressure switch, which sensor element emits a proportional electrical signal depending on the control pressure.

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

Description

Stand der TechnikState of the art

Die Erfindung geht von einer Kraftstoffeinspritzpumpe für Brennkraftmaschinen mit Abgasrückführung nach der Gattung des Patentanspruchs 1 aus. Bei einer solchen durch die DE-A-2 855 027 bekannten Kraftstoffeinspritzpumpe ist ein Fliehkraftversteller vorgesehen, der in Abhängigkeit von der Vorspannung einer Regelfeder, entgegen die der Fliehkraftversteller als Drehzahlgeber arbeitet, verstellbar ist. Die Verstellung der Regelfeder wird als Drehmomentwunsch bzw. als Lastsignal willkürlich eingegeben. Je nach Grad der Verstellung wird durch den Fliehkraftversteller ein Verbindungskanal zwischen einem kraftstoffgefüllten Innenraum mit vorgegebenen Druckniveau und einem Entlastungsraum aufgesteuert, derart, daß die abfließende Menge zumindest zum Teil ein Maß für die Last ist. Der abströmende Kraftstoff wird an einer Drossel angedrosselt und es wird somit stromaufwärts der Drossel ein Steuerdruck erzeugt, der wiederum lastabhängig sein soll und nun ein hydraulisch betätigbares Steuerelement beaufschlagt, durch das ein Stromkreis geschlossen werden kann. In dem Stromkreis liegt wiederum ein Schaltventil, das ein Stellmedium zu einem Abgasrückführventilmotor steuert. Bei der bekannten Kraftstoffeinspritzpumpe wird aber außer der Last auch noch die Drehzahl der Brennkraftmaschine bei der Bildung des Steuerdrucks wirksam, da der Fliehkraftsteller sowohl in Abhängigkeit von der Drehzahl als auch der Vorspannung der Regelfeder verstellbar ist. Somit stellt die Steuerung der Abgasrückführung keine von der tatsächlichen Betriebslast abhängige Steuerung dar.The invention is based on a fuel injection pump for internal combustion engines with exhaust gas recirculation according to the preamble of claim 1. In such a fuel injection pump known from DE-A-2 855 027, a centrifugal adjuster is provided which is adjustable depending on the preload of a control spring against which the centrifugal adjuster works as a speed sensor. The adjustment of the control spring is entered arbitrarily as a torque request or as a load signal. Depending on the degree of adjustment, the centrifugal adjuster opens a connection channel between a fuel-filled interior with a predetermined pressure level and a relief chamber, such that the amount flowing off is at least partly a measure of the load. The outflowing fuel is throttled at a throttle and thus a control pressure is generated upstream of the throttle, which in turn is to be load-dependent and now acts on a hydraulically actuatable control element by means of which a circuit can be closed. In the circuit there is in turn a switching valve which controls an actuating medium to an exhaust gas recirculation valve motor. In the known fuel injection pump, however, in addition to the load, the speed of the internal combustion engine also takes effect when the control pressure is formed, since the centrifugal force actuator is adjustable both as a function of the speed and the preload of the control spring. The control of the exhaust gas recirculation is therefore not a control dependent on the actual operating load.

Es ist zwar ferner durch die GB-A-2 031 997 eine Kraftstoffeinspritzpumpe bekannt, deren Pumpenkolben einen zweiten Kanal enthält, doch verbindet dieser zweite Kanal eine im Regelschieber pumpenkolbenseitig vorgesehene Ringnut, deren eine Begrenzungskante als die den Entlastungskanal steuernde Steuerkante ausgebildet ist, mit einer den Pumpenkohlen im Bereich des Zylinders umgebenden Ringnut, diewiederum mit einem Kraftstoffeinlaß des Pumpenarbeitsraums verbunden ist. Bei dieser bekannten Kraftstoffeinspritzpumpe dient der zweite Kanal dazu, die während des Pumpenhubes aus dem Arbeitsraum nach Beendigung der Hochdruckeinspritzung abströmende Kraftstoffmenge wieder der Saugseite der Kraftstoffeinspritzpumpe zuzuführen, und zwar in einen Speicher, der über ein zum Pumpenarbeitsraum hin öffnendes Rückschlagventil von einer gesteuerten Saugdrossel abgekoppelt ist. Mit einer solchen Einrichtung soll eine exakte Zumessung der zur Einspritzung kommenden, luftdurchsatzabhängig gesteuerten Kraftstoffmenge erzielt werden. Dies geschieht über die gesteuerte Saugdrossel und die Einbeziehung der abgesteuerten Restmenge in die Füllung des Pumpenarbeitsraumes pro Fülltakt der Kraftstoffeinspriztpumpe. Vorteile der ErfindungIt is also known from GB-A-2 031 997 a fuel injection pump, the pump piston of which contains a second channel, but this second channel connects an annular groove provided in the control slide valve on the pump piston side, one boundary edge of which is designed as the control edge controlling the relief channel, with one the annular groove surrounding the pump carbons in the area of the cylinder, which is in turn connected to a fuel inlet of the pump work space. In this known fuel injection pump, the second channel serves to supply the fuel quantity flowing out of the working space after the high-pressure injection has ended again to the suction side of the fuel injection pump, specifically into a memory which is decoupled from a controlled suction throttle via a check valve opening towards the pump working space . Such a device is intended to achieve an exact metering of the fuel quantity which is controlled as a function of the air flow and is to be injected. This is done via the controlled suction throttle and the inclusion of the scrapped residual amount in the filling of the pump work space per filling cycle of the fuel injection pump. Advantages of the invention

Die erfindungsgemäße Kraftstoffeinspritzpumpe mit den kennzeichnenden Merkmalen des Anspruchs 1 hat demgegenüber den Vorteil, daß zum Steuern des Abgasrückführventils die Stellung des Regelschiebers, die direkt für die Zumessung der für den jeweiligen Lastzustand erforderlichen Einspriztmenge maßgebend ist, als Maß für die Betriebslast der Brennkraftmaschine zugrundegelegt wird. Ein weiterer Vorteil besteht darin, daß außer der Festlegung des Abstandes des Auslasses des Entlastungskanals vom Einlaß des anderen Kanals im Pumpenkolben keine Einstell- oder Zuordnungsarbeiten erforderlich sind. Ein weiterer Vorteil besteht darin, daß der drehzahlabhängige Förderdruck einer Förderpumpe, der auch in dem den Regelschieber aufnehmenden Saugraum der Einspritzpumpe herrscht, zur Umsetzung der Stellung des Regelschiebers in ein elektrisches Signal verwendet wird.The fuel injection pump according to the invention with the characterizing features of claim 1 has the advantage that for controlling the exhaust gas recirculation valve, the position of the control slide, which is directly decisive for the metering of the injection quantity required for the respective load condition, is used as a measure of the operating load of the internal combustion engine. Another advantage is that, apart from determining the distance of the outlet of the relief channel from the inlet of the other channel in the pump piston, no adjustment or assignment work is required. Another advantage is that the speed-dependent delivery pressure of a delivery pump, which also prevails in the suction chamber of the injection pump receiving the control slide, is used to convert the position of the control slide into an electrical signal.

Durch die in den Unteransprüchen aufgeführten Maßnahmen sind vorteilhafte Weiterbildungen und Verbesserungen der im Anspruch 1 angegebenen Kraftstoffeinspritzpumpe möglich.Advantageous further developments and improvements of the fuel injection pump specified in claim 1 are possible through the measures listed in the subclaims.

Zeichnungdrawing

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt, die eine Kraftstoffeinspritzpumpe vereinfacht im Längsschnitt zeigt, und wird in der nachfolgenden Beschreibung näher erläutert.An embodiment of the invention is shown in the drawing, which shows a simplified view of a fuel injection pump in longitudinal section, and is explained in more detail in the following description.

Beschreibung des AusführungsbeispielsDescription of the embodiment

Ein Rückführen von Abgas zum Saugrohr einer Brennkraftmaschine hat sich als wirksames Mittel erwiesen, den Anteil der Schadstoffe in den Abgasen von Brennkraftmaschinen zu verringern. Insbesondere kann bei selbstzündenden Brennkraftmaschinen der hohe NOx-Anteil verringert werden. Diese durch die Kraftstoffeinspriztmenge geführten, freisaugenden Brennkraftmaschinen werden im Teillastbereich mit erheblichem Luftüberschuß betrieben, der durch Beimischen von rückgeführtem Abgas reduziert werden kann. Dadurch wird die Verbrennung so beeinflußt, daß der NOx-Schadstoffgehalt verringert wird.Returning exhaust gas to the intake manifold of an internal combustion engine has proven to be an effective means of reducing the proportion of pollutants in the exhaust gases of internal combustion engines. In particular, the high NOx content can be reduced in self-igniting internal combustion engines. These free-sucking internal combustion engines, which are guided by the fuel injection quantity, are operated in the partial-load range with considerable excess air, which can be reduced by admixing recirculated exhaust gas. This affects the combustion so that the NO x pollutant content is reduced.

In einem Gehäuse 1 einer Kraftstoffeinspritzpumpe ist eine Zylinderbüchse 3 eingesetzt, in deren Zylinder 2 ein Pumpenkolben 4 verschiebbar ist, der von einem nicht dargestellten Antrieb in eine hin- und hergehende und zugleich rotierende Bewegung versetzt wird. Der Pumpenkolben 4 schließt mit seiner einen Stirnseite einen Pumpenarbeitsraum 5 ab und ragt mit seinem anderen Ende aus der Zylinderbüchse 3 heraus in einen Saugraum 7 des Gehäuses 1. An diesem Ende ist der Pumpenkolben 4 mit dem nicht näher dargestellten Antrieb verbunden. Der Pumpenarbeitsraum 5 wird über in der Mantelfläche des Pumpenkolbens 4 angeordnete Längsnuten 8 und eine durch die Zylinderbüchse 3 und das Gehäuse 1 verlaufende Saugbohrung 9 mit Kraftstoff aus dem Pumpensaugraum 7 versorgt, solange der Pumpenkolben 4 seinen Saughub ausführt bzw. seine in Figur 1 dargestellte untere Totpunktlage einnimmt. Eine Förderpumpe 10 fördert mit drehzahlabhängig steigendem Druck Kraftstoff aus einem Kraftstoffvorratsbehälter 11 in den Saugraum 7 des Gehäuses 1. Ein zur Förderpumpe 10 parallel geschaltetes Drucksteuerventil 12 steuert den Druck im Pumpensaugraum 7 in bekannter Weise drehzahlabhängig.In a housing 1 of a fuel injection pump, a cylinder liner 3 is inserted, in the cylinder 2 of which a pump piston 4 is displaceable, which is set into a reciprocating and at the same time rotating movement by a drive (not shown). The pump piston 4 closes off one end of a pump working chamber 5 and protrudes with its other end out of the cylinder liner 3 into a suction chamber 7 of the housing 1. At this end the pump piston 4 is connected to the drive (not shown in more detail). The pump working chamber 5 is supplied with fuel from the pump suction chamber 7 via longitudinal grooves 8 arranged in the lateral surface of the pump piston 4 and a suction bore 9 running through the cylinder liner 3 and the housing 1, as long as the pump piston 4 executes its suction stroke or its lower one shown in FIG. 1 Dead center position occupies. A feed pump 10 feeds fuel from a fuel reservoir 11 into the suction space 7 of the housing 1 as the pressure increases as a function of the speed. A pressure control valve 12 connected in parallel with the feed pump 10 controls the pressure in the pump suction space 7 in a known manner as a function of the speed.

Im Pumpenkolben 4 ist ein als Sackbohrung ausgebildeter Entlastungskanal 15 angeordnet, der zum Arbeitsraum 5 hin offen ist. Von diesem Entlastungskanal 15 zweigt eine radiale Bohrung 16 ab, die zu einer Verteilernut 17 in der Mantelfläche des Pumpenkolbens 4 führt. Im Umlaufbereich dieser Verteilernut 17 zweigen in einer radialen Ebene des Zylinders 2 mehrere Förderleitungen 18 ab, die entsprechend der Zahl mit Kraftstoff zu versorgenden Zylinder der zugeordneten Brennkraftmaschine am Umfang des Zylinders 2 gleichmäßig verteilt angeordnet sind. Die Förderleitungen 18 führen zu den nicht dargestellten Kraftstoffeinspritzstellen der Brennkraftmaschine.In the pump piston 4, a relief channel 15, which is designed as a blind bore and is open to the working space 5, is arranged. A radial bore 16 branches off from this relief channel 15 and leads to a distributor groove 17 in the lateral surface of the pump piston 4. In the circumferential area of this distributor groove 17, a plurality of delivery lines 18 branch off in a radial plane of the cylinder 2 and are arranged distributed uniformly on the circumference of the cylinder 2 in accordance with the number of cylinders of the assigned internal combustion engine to be supplied with fuel. The delivery lines 18 lead to the fuel injection points, not shown, of the internal combustion engine.

Im Bereich des in den Saugraum 7 ragenden Teils des Pumpenkolbens 4 zweigt von dem Entlastungskanal 15 eine Radialbohrung 20 ab, die in der Mantelfläche des Pumpenkolbens 4 einen Auslaß A bildet. Im Bereich des Auslasses A ist auf dem Pumpenkolben 4 ein ringförmiger Regelschieber 21 als Mengenverstellorgan verschiebbar angeordnet, dessen der Zylinderbüchse 3 zugewandte Stirnseite eine Steuerkante 22 für den Auslaß A bildet. Der Regelschieber 21 wird von einer nicht dargestellten Regeleinrichtung aufgrund von mehreren Betriebsparametern, wie Drehzahlwunsch, Drehzahl, Luftdruck, Temperatur u. dgl. über einen Regelhebel 23 axial zum Pumpenkolben 4 verstellt. Der Regelschieber 21 nimmt dabei bei großer Kraftstoffeinspritzmenge eine in der Figur dargestellte Stellung ein, in der in der unteren Totpunktlage des Pumpenkolbens 4 der Abstand des Auslasses A des Entlastungskanals 15 zur Steuerkante 22 des Regelschiebers 21 das Maß sv hat. Zum Fördern geringerer Einspritzmengen im Teillastbereich wird der Regelschieber 21 bezogen auf die Zeichnung nach links verstellt, so daß der Abstand zwischen dem Auslaß A und der Steurkante 22 sich verringert. Dadurch wird der jeweils zur Verfügung stehende Nutzhub, den der Pumpenkolben 4 bzw. der Auslaß A von unteren Totpunkt des Pumpenkolbens 4 zurücklegen muß, verändert. Die Stellung der Steuerkante 22 des Regelschiebers 21 ist daher maßgebend für die jeweilige Größe der Einspritzmenge in einem bestimmten Lastbereich der Brennkraftmaschine.In the area of the part of the pump piston 4 projecting into the suction space 7, a radial bore 20 branches off from the relief channel 15 and forms an outlet A in the outer surface of the pump piston 4. In the area of the outlet A, an annular regulating slide 21 is displaceably arranged on the pump piston 4 as a quantity adjusting member, the end face of which facing the cylinder liner 3 forms a control edge 22 for the outlet A. The control slide 21 is from a control device, not shown, due to several operating parameters, such as desired speed, speed, air pressure, temperature and. Like. Axially adjusted to the pump piston 4 via a control lever 23. In the case of a large fuel injection quantity, the control slide 21 assumes a position shown in the figure, in which, in the bottom dead center position of the pump piston 4, the distance between the outlet A of the relief channel 15 and the control edge 22 of the control slide 21 has the dimension s v . To promote lower injection quantities in the partial load range, the control slide 21 is adjusted to the left with reference to the drawing, so that the distance between the outlet A and the control edge 22 is reduced. The useful stroke available in each case, which the pump piston 4 or the outlet A must travel from the bottom dead center of the pump piston 4, is thereby changed. The position of the control edge 22 of the control slide 21 is therefore decisive for the respective size of the injection quantity in a specific load range of the internal combustion engine.

Im Pumpenkolben 4 ist ferner ein zweiter Kanal 25 angeordnet, von dem im Bereich des sich ständig im Zylinder 2 befindlichen Pumpenkolben-Abschnitts eine Radialbohrung 26 mit einem Auslaß B und im Wirkbereich des Regelschiebers 21 eine Radialbohrung 27 mit einem Einlaß E abzweigen. In der unteren Totpunktlage des Pumpenkolbens 4 und bei Stellung des Regelschiebers 21 in der Vollaststellung (wie in der Zeichnung dargestellt) hat der Einlaß E des Kanals 25 zu der Steuerkante 22 des Regelschiebers 21 einen Abstand SL, der größer ist als der Abstand Sv des Auslasses A des Entlastungskanals 15 von der Steuerkante 22, so daß der Einlaß E des Kanals 25 zum Auslaß A des Entlastungskanals 15 um einen bestimmten Abstand versetzt ist. Aufgrund dieser Anordnung wird erreicht, daß der Kanal 25 beim Hub des Pumpenkolbens 4 erst geöffnet wird, nachdem der Auslaß A der Entlastungsbohrung 15 bereits aufgesteuert worden ist. Dies hat zur folge, daß bei Vollastbetrieb, wenn der Regelschieber 21 in seine äußerste rechte Stellung (Zeichnung) verstellt ist, der Einlaß E des Kanals 25 beim Druckhub des Pumpenkolbens 4 überhaupt nicht geöffnet wird. Dagegen wird der Einlaß E vom Regelschieber 21 gegen Ende des Druckhubes des Pumpenkolbens 4 freigegeben, wenn der Regelschieber im Teillastbereich eine Stellung einnimmt, die bezogen auf die Zeichnung links von der dargestellten Stellung liegt und in der beim Pumpenkolbenhub der Auslaß A der Entlastungsbohrung 15 bereits aufgesteuert ist, wenn der Einlaß E des Kanals 25 die Steuerkante 22 des Regelschiebers 21 erreicht.In the pump piston 4 there is also a second channel 25, from which a radial bore 26 with an outlet B branches off in the area of the pump piston section which is always in the cylinder 2, and a radial bore 27 with an inlet E branches off in the effective range of the control slide 21. In the bottom dead center position of the pump piston 4 and when the control slide 21 is in the full-load position (as shown in the drawing), the inlet E of the channel 25 to the control edge 22 of the control slide 21 has a distance SL which is greater than the distance Sv of the outlet A of the relief channel 15 from the control edge 22, so that the inlet E of the channel 25 to the outlet A of the relief channel 15 is offset by a certain distance. Because of this arrangement, it is achieved that the channel 25 is only opened during the stroke of the pump piston 4 after the outlet A of the relief bore 15 has already been opened. This has the consequence that in full load operation, when the control slide 21 is adjusted to its rightmost position (drawing), the inlet E of the channel 25 is not opened at all during the pressure stroke of the pump piston 4. In contrast, the inlet E is released by the control slide 21 towards the end of the pressure stroke of the pump piston 4 when the control slide assumes a position in the partial load range which is to the left of the position shown in the drawing and in which the outlet A of the relief bore 15 is already opened during the pump piston stroke is when the inlet E of the channel 25 reaches the control edge 22 of the control slide 21.

Im Bereich des Auslasses B des Kanals 25 ist in der Zylinderbüchse 3 eine Ringnut 28 angeordnet, die über eine radiale Bohrung 29 in der Zylinderbüchse 3 und eine Bohrung 30 mit einer Sackbohrung 31 verbunden ist. Von der Sackbohrung 31 zweigt eine Bohrung 32 zu einer Abströmdrossel 33 ab, von der aus eine Leitung 34 zum drucklosen Kraftstoffvorratsbehälter 11 führt.In the area of the outlet B of the channel 25, an annular groove 28 is arranged in the cylinder liner 3, which is connected via a radial bore 29 in the cylinder liner 3 and a bore 30 to a blind bore 31. A bore 32 branches off from the blind bore 31 to an outflow throttle 33, from which a line 34 leads to the unpressurized fuel reservoir 11.

In die Sackbohrung 31 ist ein an sich bekannter Druckschalter 35 eingeschraubt, der bei einem Druck, der im Bereich des im Saugraum 7 herrschenden Förderdruckes liegt, einen elektrischen Kontakt 37 schließt und damit ein elektrisches Signal zum Steuern eines Abgasrückführventils der Brennkraftmaschine erzeugt. Die Beaufschlagung des Druckschalters 35 mit Kraftstoff aus dem Saugraum 7 und dem dort herrschenden Druck wird in Abhängigkeit von der Stellung des Regelschiebers 21 gesteuert. Wie oben erwähnt, wird der Einlaß des Kanals 25, der über die Ringnut 28 und die Bohrungen 29 und 30 mit dem Druckschalter 35 verbunden ist, bei der Vollaststellung des Regelschiebers 21 während des Resthubs des Pumpenkolbens 4 nach dem Aufsteuern des Auslasses A nicht geöffnet, so daß die über die Abströmdrossel 33 druckentlastete Sackbohrung 31 und damit der Druckschalter 35 drucklos sind. Dagegen wird bei einer Stellung des Regelschiebers 21 im Teillastbereich der Einlaß E des Kanals 25 gegen Ende des Druckhubes des Pumpenkolbens 4 aufgesteuert, so daß der Druck im Saugraum 7 durch den Kanal 25 und die Bohrungen 29,30 auf den Druckschalter 35 wirken kann. Bei Druckbeaufschlagung wird der Kontakt 37 des Druckschalters 35 geschlossen, so daß ein elektrisches Steuersignal erzeugt wird, daß direkt zum Öffnen des Abgasrückführventils der Brennkraftmaschine verwendet werden kann oder als Steuersignal dient.A pressure switch 35 known per se is screwed into the blind bore 31 and closes an electrical contact 37 at a pressure which is in the range of the delivery pressure prevailing in the suction chamber 7 and thus generates an electrical signal for controlling an exhaust gas recirculation valve of the internal combustion engine. The application of fuel to the pressure switch 35 from the suction space 7 and the pressure prevailing there is controlled as a function of the position of the control slide 21. As mentioned above, the inlet of the channel 25, which is connected to the pressure switch 35 via the annular groove 28 and the bores 29 and 30, is not opened when the control slide 21 is in the fully loaded position during the remaining stroke of the pump piston 4 after opening A has been opened, so that the pressure-relieved via the outflow throttle 33 blind bore 31 and thus the pressure switch 35 are depressurized. In contrast, with a position of the control slide 21 in the partial load range, the inlet E of the channel 25 is opened towards the end of the pressure stroke of the pump piston 4, so that the pressure in the suction space 7 through the channel 25 and the bores 29, 30 can act on the pressure switch 35. When pressure is applied, the contact 37 of the pressure switch 35 is closed, so that an electrical control signal is generated that can be used directly to open the exhaust gas recirculation valve of the internal combustion engine or serves as a control signal.

Um zu vermeiden, daß eine zu starke Druckpulsation auf den Druckschalter 35 wirkt, kann eine Drossel 36 in der radialen Bohrung 29 in der Zylinderbüchse 3 angeordnet werden.In order to avoid that excessive pressure pulsation acts on the pressure switch 35, a Throttle 36 can be arranged in the radial bore 29 in the cylinder liner 3.

Ergänzend wird bemerkt, daß zum Erzeugen eines der Drehzahl und/oder der Last proportionalen elektrischen Signals anstelle des Druckschalters ein druckempfindliches Sensorelement angeordnet werden kann, das in Abhängigkeit zum Steuerdruck ein proportionales elektrisches Signal abgibt.In addition, it is noted that in order to generate an electrical signal proportional to the speed and / or the load, a pressure-sensitive sensor element can be arranged instead of the pressure switch, which sensor element emits a proportional electrical signal depending on the control pressure.

Claims (6)

1. Fuel injection pump for internal-combustion engines with exhaust gas recirculation with a load-dependently operated electric control element (35) for the emission of an electric signal for controlling an exhaust gas recirculation valve, with a pump piston (4), which is driven reciprocatingly and at the same time rotatingly in a cylinder (2) and closes off a pump working space (5), in which piston a relief channel (15), permanently connected to the pump working space, is arranged, and with a load-dependently adjustable control slide valve (21), which surrounds the pump piston in a space (7) impinged by fuel pressure and closes the outlet (A) of the relief channel during a variable part of the stroke path of the pump piston, the control element (35) being hydraulically operable, characterized in that in the pump piston (4) there is arranged a second channel (25), the outlet (B) of which is in connection with a line (29, 30) leading to the control element (35), and the inlet (E) of which is arranged in the effective region of the control slide valve (21) at a distance from the outlet (A) of the relief channel (15) in such a way that the inlet (E) of the channel (25) is only open if the outlet of the relief channel has been opened under control.
2. Fuel injection pump according to Claim 1, characterized in that the inlet (E) of the channel (25) is away from the outlet (A) of the relief channel (15) by a distance which is greater than the remaining stroke of the pump piston (4) after opening of the outlet (A) by the control slide valve (21) in the full-load position of the latter.
3. Fuel injection pump according to Claim 1 or 2, characterized in that a flow-off restrictor (33) is connected to the connection point of the control element (35).
4. Fuel injection pump according to Claim 3, characterized in that a restrictor (36) is arranged in the line (29, 30) leading to the control element (35).
5. Fuel injection pump according to one of Claims 1 to 4, characterized in that the control element is an electric switch (35).
6. Fuel injection pump according to one of Claims 1 to 4, characterized in that the control element is a pressure sensor which emits an electric signal proportional to the pressure applied.
EP87102705A 1986-04-10 1987-02-26 Fuel injection pump for internal-combustion engines with exhaust gas recirculation Expired - Lifetime EP0240686B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19863612068 DE3612068A1 (en) 1986-04-10 1986-04-10 FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES WITH EXHAUST GAS RECIRCULATION
DE3612068 1986-04-10

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EP0240686A1 EP0240686A1 (en) 1987-10-14
EP0240686B1 true EP0240686B1 (en) 1990-05-02

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EP (1) EP0240686B1 (en)
JP (1) JPS62261662A (en)
DE (2) DE3612068A1 (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3644147A1 (en) * 1986-12-23 1988-07-07 Bosch Gmbh Robert FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES
DE3644583A1 (en) * 1986-12-27 1988-07-07 Bosch Gmbh Robert FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES
DE3740968C1 (en) * 1987-12-03 1988-12-15 Bosch Gmbh Robert Exhaust gas recirculation device for internal combustion engines
DE4106813A1 (en) * 1991-03-04 1992-09-10 Bosch Gmbh Robert FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES
DE19713868A1 (en) * 1997-04-04 1998-10-08 Bosch Gmbh Robert Fuel injection pump for internal combustion engines
US6050248A (en) * 1997-12-03 2000-04-18 Caterpillar Inc. Exhaust gas recirculation valve powered by pressure from an oil pump that powers a hydraulically actuated fuel injector
US5865156A (en) * 1997-12-03 1999-02-02 Caterpillar Inc. Actuator which uses fluctuating pressure from an oil pump that powers a hydraulically actuated fuel injector
US6148805A (en) * 1998-12-15 2000-11-21 Caterpillar Inc. Engine with hydraulic fuel injection and EGR valve using a single high pressure pump
JP3771454B2 (en) * 2001-02-21 2006-04-26 本田技研工業株式会社 Control device for internal combustion engine

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2520812A1 (en) * 1982-02-03 1983-08-05 Bosch Gmbh Robert FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2353737A1 (en) * 1973-10-26 1975-05-07 Bosch Gmbh Robert FUEL INJECTION PUMP FOR COMBUSTION MACHINES
DE2448693C2 (en) * 1974-10-12 1983-11-24 Robert Bosch Gmbh, 7000 Stuttgart Speed controller for a distributor injection pump
DE2855027A1 (en) * 1976-12-22 1980-07-10 Bosch Gmbh Robert DEVICE FOR ACTUATING AN ACTUATING ELEMENT IN A COMBUSTION ENGINE ON AN EXHAUST GAS RECIRCULATION CONTROL DEVICE
US4090950A (en) * 1977-04-26 1978-05-23 Sun Petroleum Products Company Process for manufacturing refrigeration oils
DE2841807A1 (en) * 1978-09-26 1980-04-03 Bosch Gmbh Robert DEVICE FOR REGULATING THE QUANTITY OF AIR / FUEL IN INTERNAL COMBUSTION ENGINES
JPS5627058A (en) * 1979-08-13 1981-03-16 Toyota Motor Corp Exhaust gas recycling controller in internal combustion engine
DE2946557A1 (en) * 1979-11-17 1981-05-27 Robert Bosch Gmbh, 7000 Stuttgart DEVICE FOR CONTROLLING AN EXHAUST GAS RECIRCULATION DEVICE IN INTERNAL COMBUSTION ENGINES
DE3013087A1 (en) * 1980-04-03 1981-10-15 Robert Bosch Gmbh, 7000 Stuttgart FUEL INJECTION PUMP FOR SELF-IGNITIONING INTERNAL COMBUSTION ENGINES
JPS57137644A (en) * 1981-02-19 1982-08-25 Mazda Motor Corp Exhaust gas recirculation device for diesel engine
US4411242A (en) * 1981-04-03 1983-10-25 Nippon Soken, Inc. Method and apparatus for controlling EGR in internal combustion engine
DE3135234A1 (en) * 1981-09-05 1983-03-17 Robert Bosch Gmbh, 7000 Stuttgart DEVICE FOR THE LOAD-RELATED OPERATION OF AN ACTUATOR OF AN INTERNAL COMBUSTION ENGINE
DE3138606A1 (en) * 1981-09-29 1983-04-14 Robert Bosch Gmbh, 7000 Stuttgart FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES
JPS5885353A (en) * 1981-11-17 1983-05-21 Nissan Motor Co Ltd Exhaust gas recirculation controller of internal combustion engine
US4537170A (en) * 1984-02-28 1985-08-27 Diesel Kiki Co., Ltd. Distribution type fuel injection pump
DE3424883A1 (en) * 1984-07-06 1986-02-06 Robert Bosch Gmbh, 7000 Stuttgart FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES
JP3363031B2 (en) * 1996-06-24 2003-01-07 株式会社クボタ Slag cleaning method and slag cleaning device

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2520812A1 (en) * 1982-02-03 1983-08-05 Bosch Gmbh Robert FUEL INJECTION PUMP FOR INTERNAL COMBUSTION ENGINES

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US4718385A (en) 1988-01-12
JPS62261662A (en) 1987-11-13
DE3612068A1 (en) 1987-10-15
EP0240686A1 (en) 1987-10-14
DE3762536D1 (en) 1990-06-07

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