EP0083001A1 - Système d'injection de combustible pour l'injection directe de combustible dans les moteurs à combustion interne - Google Patents

Système d'injection de combustible pour l'injection directe de combustible dans les moteurs à combustion interne Download PDF

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Publication number
EP0083001A1
EP0083001A1 EP82111427A EP82111427A EP0083001A1 EP 0083001 A1 EP0083001 A1 EP 0083001A1 EP 82111427 A EP82111427 A EP 82111427A EP 82111427 A EP82111427 A EP 82111427A EP 0083001 A1 EP0083001 A1 EP 0083001A1
Authority
EP
European Patent Office
Prior art keywords
injection
fuel
fuel injection
injection quantity
combustion chamber
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.)
Granted
Application number
EP82111427A
Other languages
German (de)
English (en)
Other versions
EP0083001B1 (fr
Inventor
Hermann Grieshaber
Hans-Joachim Siebert
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP0083001A1 publication Critical patent/EP0083001A1/fr
Application granted granted Critical
Publication of EP0083001B1 publication Critical patent/EP0083001B1/fr
Expired legal-status Critical Current

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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
    • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/14—Arrangements of injectors with respect to engines; Mounting of injectors
    • 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
    • F02M45/00—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
    • F02M45/02—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts
    • F02M45/04—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts with a small initial part, e.g. initial part for partial load and initial and main part for full load
    • 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
    • F02M45/00—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
    • F02M45/02—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts
    • F02M45/04—Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts with a small initial part, e.g. initial part for partial load and initial and main part for full load
    • F02M45/08—Injectors peculiar thereto
    • F02M45/086—Having more than one injection-valve controlling discharge orifices
    • 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
    • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
    • F02M2200/44—Valves, e.g. injectors, with valve bodies arranged side-by-side

Definitions

  • the invention is based on a fuel injection system according to the preamble of the main claim.
  • the pre-injection quantity is introduced into the combustion chambers of an internal combustion engine separately from the main fuel injection quantity via a special fuel injection valve arrangement in the form of a double valve.
  • the pre-injection quantity is controlled by a separate pump arrangement and the main injection quantity by a conventional fuel injection pump.
  • the pre-injection quantity is constant in the known device, however, the injection timing, the advance of the injection compared to the main injection, can be controlled depending on the load and speed.
  • a small fuel injection quantity is pre-injected before the main injection quantity is injected, the combustion starts "softly" with this small injection quantity.
  • the required ignition temperature for the entering fuel is already reached by burning the pre-injection quantity.
  • the main injection quantity can then be burned directly in the combustion chamber to the extent that it is injected without a long ignition delay.
  • the combustion pressure curve in such a combustion is less steep and the noise associated with the combustion is low.
  • this injection method has the disadvantage that the main injection quantity no longer has the possibility of intensively mixing with the air present in the combustion chamber before the onset of combustion.
  • the fuel consumption and also the smoke development with this combustion process are higher than with the one previously described.
  • the fuel injection system according to the invention with the characterizing features of the main claim has the advantage that numerous strong local turbulences arise in the combustion chamber by the type of introduction of the pre-injection quantity, which become effective at the time of the main injection.
  • the preparation of the main fuel injection quantity is significantly improved by this local turbulence.
  • the injection valves are arranged as close as possible to the center of a combustion chamber designed as a combustion chamber trough and the injection jets of the pre-injection quantity form a cone that is smaller than the cone formed by the jets of the main injection quantity, local turbulence is specifically generated at the points in the combustion chamber that Beginning of the main injection of which fluid jets are touched.
  • the pre-injection quantity and the pre-injection time are controlled as a function of the load and speed.
  • the pilot injection can thus be optimized with regard to the increase in combustion pressure and with regard to the preparation of the main fuel injection quantity.
  • the injection geometry and the fuel pressure are advantageously coordinated with one another in such a way that the fuel is atomized directly in the combustion chamber. This avoids fuel wetting of the combustion chamber walls and ensures that the fuel is completely burned during the work cycle.
  • FIG. 1 shows the schematic arrangement of the injection system according to the invention with a double injection valve and in each case one injection pump for the main injection and the pre-injection
  • FIG. 2 shows the arrangement of the double injection valve and the spray directions in a side view
  • FIG. 3 shows the injection spray distribution in a top view.
  • FIG. 1 an internal combustion engine 1 is shown schematically and a double injection valve 2 assigned to a cylinder of the internal combustion engine.
  • a double injection valve 2 assigned to a cylinder of the internal combustion engine.
  • injection valves are known, for. B. by DE-OS 29 43 895, and need not be described here.
  • the valve body 3 has a first outlet point 4 for the pre-injection quantity and a second outlet point 5 for the main injection quantity.
  • the double injection valve is supplied with fuel by a first fuel injection pump 6 and by a second fuel injection pump 7.
  • the first fuel Injection pump supplies the individual double valves of the internal combustion engine with fuel via pre-injection lines 8 and the second fuel injection pump 7 delivers the main fuel injection quantity via main injection lines 9.
  • the second fuel injection pump 7 for the main injection can, for. B. be designed as a series injection pump and is connected via a spray adjustment device 11 to the drive of the internal combustion engine.
  • the first fuel injection pump 6 is further coupled, the z. B. can be a distributor injection pump with an integrated spray adjuster 12.
  • both the main injection quantity and the pre-injection quantity can be precisely controlled in terms of time and quantity.
  • the pre-injection quantity and the injection timing of the pre-injection quantity are controlled in a manner known per se depending on the load and speed, the quantity and injection timing being matched to the main injection quantity and its timing.
  • Ratios per injection quantity to injection quantity can be set from 1: 1.3 to 1:28.
  • the start of injection of the pre-injection quantity can be set 10 to 20 ° crank angle before the start of injection of the main injection quantity.
  • the pre-injection quantity is injected into the combustion chamber through a plurality of spray openings.
  • 2 shows such a preferably trough-shaped combustion chamber 14, which is arranged within a piston 15.
  • the double injection valve 2 protrudes obliquely through the cylinder head into the combustion chamber, at a point that is as close as possible to the center Z of the combustion chamber.
  • the design of the double injection valve means that the outlet points of the pre-injection quantity and the main injection quantity are very close to one another.
  • other embodiments of double injection valves can of course also be used, a coaxial arrangement being conceivable instead of the secondary arrangement.
  • the double injection valve has four injection openings 16 at the first exit point 4, which together form a cone angle of ⁇ 1.
  • the double injection valve also has four injection openings 17, which together enclose a conical angle of ⁇ 2.
  • the tip cone angle ⁇ 2 is larger than the tip cone angle ⁇ 1.
  • the opening area of the injection openings 16 is smaller than the opening area of the injection openings 17 with a corresponding adjustment of the fuel quantities to be injected there in order to achieve the best possible atomization of the introduced fuel.
  • the injection openings 16 and 17 are aligned such that the fuel to be injected is distributed uniformly over the surface of the combustion chamber, as can be seen in FIG. 3.
  • the direction of injection of the pre-injection jets is to be oriented in the projection to the combustion chamber 14 in such a way that they are upstream in the direction of movement of the directed air swirl in the combustion chamber from the direction of injection of the main injection jets.
  • the measures described reduce the combustion noise with the help of the pre-injection and still achieve a very good preparation of the injected fuel both in the pre-injection quantity and in the main injection quantity combined with favorable result criteria such as specific fuel consumption, black smoke and exhaust gas emissions.
  • the processing can be done by appropriate adjustment of injection geometry, e.g. B. injection opening area and injection pressure can be optimized.
  • the injection jets should in particular supply the compressed rotating air (due to the centrifugal force) in the vicinity of the combustion chamber with sufficient fuel.
  • the exact control ensures that the strength and timing of numerous local vortices (secondary vortices) that also result from the pre-combustion represent a substitute for the mixing duration removed from the main injection during the usual ignition delay.

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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)
EP82111427A 1981-12-24 1982-12-09 Système d'injection de combustible pour l'injection directe de combustible dans les moteurs à combustion interne Expired EP0083001B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3151293 1981-12-24
DE19813151293 DE3151293A1 (de) 1981-12-24 1981-12-24 Kraftstoffeinspritzsystem fuer kraftstoffdirekteinspritzung bei brenn-kraftmaschinen

Publications (2)

Publication Number Publication Date
EP0083001A1 true EP0083001A1 (fr) 1983-07-06
EP0083001B1 EP0083001B1 (fr) 1988-04-20

Family

ID=6149672

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82111427A Expired EP0083001B1 (fr) 1981-12-24 1982-12-09 Système d'injection de combustible pour l'injection directe de combustible dans les moteurs à combustion interne

Country Status (4)

Country Link
US (1) US4549511A (fr)
EP (1) EP0083001B1 (fr)
JP (1) JPS58117355A (fr)
DE (2) DE3151293A1 (fr)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3683962D1 (de) * 1985-07-01 1992-04-02 Easthorpe Investments Ltd Zentrifugalpumpe.
USRE33841E (en) * 1986-04-24 1992-03-10 General Motors Corporation Dual spray cone electromagnetic fuel injector
FR2663084B1 (fr) * 1990-06-07 1992-07-31 Semt Pielstick Dispositif d'injection pour moteur a combustion interne.
DE19651175C2 (de) * 1996-12-10 1999-12-30 Otto C Pulch Gegenkolben-Zweitakt-Verbrennungsmotor mit Direkteinspritzung des Kraftstoffes in den Zylinder und regelbarer Rotation und Turbulenz der Ladeluft
DE19716221B4 (de) * 1997-04-18 2007-06-21 Robert Bosch Gmbh Kraftstoffeinspritzeinrichtung mit Vor- und Haupteinspritzung bei Brennkraftmaschinen, insbesondere für schwer zündbare Kraftstoffe
US7574992B2 (en) * 2007-01-16 2009-08-18 Deere & Company Fuel injector with multiple injector nozzles for an internal combustion engine
DE102008044244A1 (de) * 2008-12-01 2010-06-02 Robert Bosch Gmbh Brennkraftmaschine
US20140090622A1 (en) * 2012-09-28 2014-04-03 Harold Cranmer Seelig Internal combustion engine
DE102013203271A1 (de) * 2013-02-27 2014-08-28 Mtu Friedrichshafen Gmbh Einspritzventil einer Kraftstoffeinbringvorrichtung einer Brennkraftmaschine, Kraftstoffeinbringvorrichtung sowie Brennkraftmaschine

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB340664A (en) * 1928-11-12 1931-01-08 Hugo Junkers Improvements in and relating to diesel engines
US1857192A (en) * 1931-06-20 1932-05-10 James J Hauser Fuel injector nozzle for internal combustion engines
DE1042964B (de) * 1954-06-11 1958-11-06 Kloeckner Humboldt Deutz Ag Brennstoffeinspritzduese fuer Brennkraftmaschinen
DE2025569A1 (de) * 1969-06-18 1970-12-23 F.F.S.A., Paris Einspritzdüse mit Koppeleinspritzung für Verbrennungsmotoren
DE2325822A1 (de) * 1972-05-30 1973-12-13 List Hans Einspritzduese fuer brennkraftmaschinen
DE2849778A1 (de) * 1977-11-23 1979-05-31 Volvo Ab Kraftstoffeinspritzung fuer verbrennungskraftmaschinen nach dem dieselprinzip

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GB151656A (en) * 1918-02-18 1920-10-07 Albert Thorpe Improvements in devices for use in unrolling piece goods
DE379453C (de) * 1921-03-06 1923-08-24 Maschf Augsburg Nuernberg Ag Verfahren zur unmittelbaren Einspritzung schwer entzuendlichen Brennstoffes in Verbrennungskraftmaschinen
US1767701A (en) * 1924-10-25 1930-06-24 Maschf Augsburg Nuernberg Ag Internal-combustion engine of the solid-fuel injection type
US2145640A (en) * 1932-05-11 1939-01-31 Ex Cell O Corp Fluid distribution system
DE879934C (de) * 1950-01-05 1953-06-18 Stuttgarter Motorzubehoer G M Verbrennungsverfahren fuer kompressorlose Dieselmotoren
DE1808650A1 (de) * 1968-11-13 1970-06-18 Bosch Gmbh Robert Kraftstoffeinspritzvorrichtung
DD102198A1 (fr) * 1973-02-02 1973-12-05
GB1578131A (en) * 1976-05-14 1980-11-05 Lucas Industries Ltd Fuel supply systems for engines
DE2711350A1 (de) * 1977-03-16 1978-09-21 Bosch Gmbh Robert Kraftstoffeinspritzduese fuer brennkraftmaschinen
JPS586423B2 (ja) * 1977-06-10 1983-02-04 ケイディディ株式会社 交換台における呼の配布方式
JPS5438439A (en) * 1977-08-30 1979-03-23 Agency Of Ind Science & Technol Fuel injection for pump multiple injection
DE2753953A1 (de) * 1977-12-03 1979-06-07 Daimler Benz Ag Verfahren zum betrieb einer luftverdichtenden selbstzuendenden brennkraftmaschine sowie geeignetes einspritzventil
DE2826602C2 (de) * 1978-06-19 1982-07-15 M.A.N. Maschinenfabrik Augsburg-Nürnberg AG, 8500 Nürnberg Luftverdichtende, direkteinspritzende Brennkraftmaschine
JPS5515620A (en) * 1978-07-20 1980-02-02 Fujitsu Ltd Washing method
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DE2901210C2 (de) * 1979-01-13 1984-01-12 Klöckner-Humboldt-Deutz AG, 5000 Köln Verfahren zum Betrieb einer luftverdichtenden, selbstzündenden Brennkraftmaschine
DE2924128A1 (de) * 1979-06-15 1980-12-18 Motoren Werke Mannheim Ag Einrichtung zur einspritzung von zuendkraftstoff einerseits und zuendunwilligem hauptkraftstoff andererseits fuer dieselmotoren
DE2943896A1 (de) * 1979-10-31 1981-05-14 Robert Bosch Gmbh, 7000 Stuttgart Kraftstoffeinspritzduese fuer brennkraftmaschinen
DE2943895A1 (de) * 1979-10-31 1981-05-14 Robert Bosch Gmbh, 7000 Stuttgart Kraftstoffeinspritzduese fuer brennkraftmaschinen
JPS603982Y2 (ja) * 1979-12-12 1985-02-04 株式会社小松製作所 デイゼルエンジンの燃料噴射装置
DE3002851A1 (de) * 1980-01-26 1981-07-30 Motoren-Werke Mannheim AG, vorm. Benz Abt. stat. Motorenbau, 6800 Mannheim Einrichtung zur einspritzung von zuendkraftstoff einerseits und zuendunwilligem hauptkraftstoff andererseits fuer dieselmotoren
DE3003411C2 (de) * 1980-01-31 1983-07-28 M.A.N. Maschinenfabrik Augsburg-Nürnberg AG, 8500 Nürnberg Selbstzündende Hubkolben-Brennkraftmaschine

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB340664A (en) * 1928-11-12 1931-01-08 Hugo Junkers Improvements in and relating to diesel engines
US1857192A (en) * 1931-06-20 1932-05-10 James J Hauser Fuel injector nozzle for internal combustion engines
DE1042964B (de) * 1954-06-11 1958-11-06 Kloeckner Humboldt Deutz Ag Brennstoffeinspritzduese fuer Brennkraftmaschinen
DE2025569A1 (de) * 1969-06-18 1970-12-23 F.F.S.A., Paris Einspritzdüse mit Koppeleinspritzung für Verbrennungsmotoren
DE2325822A1 (de) * 1972-05-30 1973-12-13 List Hans Einspritzduese fuer brennkraftmaschinen
DE2849778A1 (de) * 1977-11-23 1979-05-31 Volvo Ab Kraftstoffeinspritzung fuer verbrennungskraftmaschinen nach dem dieselprinzip

Also Published As

Publication number Publication date
JPS58117355A (ja) 1983-07-12
US4549511A (en) 1985-10-29
DE3278370D1 (en) 1988-05-26
DE3151293A1 (de) 1983-07-07
EP0083001B1 (fr) 1988-04-20
JPH0475391B2 (fr) 1992-11-30

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