EP1321661A2 - Soupape d'injection de combustible pour moteurs à combustion interne - Google Patents

Soupape d'injection de combustible pour moteurs à combustion interne Download PDF

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Publication number
EP1321661A2
EP1321661A2 EP02017114A EP02017114A EP1321661A2 EP 1321661 A2 EP1321661 A2 EP 1321661A2 EP 02017114 A EP02017114 A EP 02017114A EP 02017114 A EP02017114 A EP 02017114A EP 1321661 A2 EP1321661 A2 EP 1321661A2
Authority
EP
European Patent Office
Prior art keywords
valve
valve seat
bore
conical
fuel injection
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP02017114A
Other languages
German (de)
English (en)
Other versions
EP1321661A3 (fr
EP1321661B1 (fr
Inventor
Friedrich Boecking
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 EP1321661A2 publication Critical patent/EP1321661A2/fr
Publication of EP1321661A3 publication Critical patent/EP1321661A3/fr
Application granted granted Critical
Publication of EP1321661B1 publication Critical patent/EP1321661B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
    • F02M61/18—Injection nozzles, e.g. having valve seats; Details of valve member seated ends, not otherwise provided for
    • F02M61/1873—Valve seats or member ends having circumferential grooves or ridges, e.g. toroidal
    • 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
    • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
    • F02M61/18—Injection nozzles, e.g. having valve seats; Details of valve member seated ends, not otherwise provided for
    • 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
    • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
    • F02M61/18—Injection nozzles, e.g. having valve seats; Details of valve member seated ends, not otherwise provided for
    • F02M61/1866—Valve seats or member ends having multiple cones

Definitions

  • the invention relates to a fuel injection valve for Internal combustion engines, as described in DE 199 42 370 A1 is known.
  • a valve needle longitudinally displaceable in the bore of a valve body arranged, being between the wall of the bore and the valve needle can be filled with fuel under high pressure Pressure chamber is formed.
  • On the combustion chamber side At the end of the bore there are several injection openings in the valve body trained through which the bore with the combustion chamber the internal combustion engine is connected.
  • a conical valve seat is formed at the end, on which the valve needle in its closed position with a Valve sealing surface comes to the plant. In the closed position the valve needle cannot deliver the fuel from the pressure chamber flow to the injection ports.
  • Fuel flows out of the pressure chamber from the valve seat between the valve sealing surface and the valve seat to the injection openings and from there into the combustion chamber injected into the internal combustion engine.
  • the valve sealing surface has two conical surfaces, the first conical surface upstream of the second conical Surface is arranged and both conical surfaces directly against each other limits.
  • the opening angle of the first conical Area is smaller than the opening angle of the valve seat, which in turn is smaller than the opening angle the second conical surface. This will make the transition of the two conical surfaces formed a ring edge, which in Closed position of the valve needle on the valve seat to the system comes and due to the relatively high surface pressure a good one Creates tightness.
  • the valve needle is in the bore by the hydraulic Counteracts pressure that acts on parts of the valve sealing surface a closing force directed at the valve seat.
  • the pressure at which the valve needle is just coming from the valve seat takes off, is called opening pressure.
  • This is depending on the hydraulically effective seat diameter of the valve needle on the valve seat, which is described in the above Geometry corresponds to the diameter of the sealing edge. This however only applies as long as there is no deformation of the valve needle and valve seat occur. There is always one in operation elastic and, especially after prolonged use, to one plastic deformation of the valve sealing surface by the Valve needle. So can the hydraulically effective seat diameter the valve needle change over time and thus also the opening pressure.
  • the difference angle between the first conical Area and the conical valve seat larger than that Difference angle between the second conical surface and the valve seat. This ensures the constancy of the hydraulic effective seat diameter further supported.
  • the first Ring groove designed as a flat countersink of the hole.
  • the first ring groove can be done in a simple manner manufacture with high precision. It is particularly advantageous here that the first ring groove always without further action remains connected to the pressure chamber so that the valve sealing surface of the fuel pressure in the pressure chamber at all times is acted upon.
  • FIG. 1 is an embodiment of the invention Fuel injector shown in longitudinal section.
  • a bore 3 is formed, the one Has longitudinal axis 8 and in which a piston-shaped valve needle 5 is arranged to be longitudinally displaceable.
  • On the combustion chamber side is a conical valve seat 9 arranged in which at least one injection opening 11 is formed is in the installed position of the fuel injector opens into the combustion chamber of the internal combustion engine.
  • the Valve needle 5 is in a guide section 23 of the bore 3 sealing led and tapers to the combustion chamber below Formation of a pressure shoulder 13. On its combustion chamber side At the end, the valve needle 5 goes into a valve sealing surface 7 over, in the closed position of the valve needle 5 on the valve seat 9 is present.
  • a pressure chamber 19 is formed, which is at the level of Pressure shoulder 13 is expanded radially.
  • This radial expansion of the pressure chamber 19 opens into the valve body 1 running inlet bore 25 through which the pressure chamber 19 with a high-pressure fuel source is connected in the pressure chamber 19 constant or intermittent high fuel pressure builds.
  • the valve needle 5 is by one in the drawing Applied device, not shown, with a closing force on the valve needle 5 in the direction of the valve seat 9 acts. As a result, the valve needle 5 with the valve sealing surface 7 pressed against the valve seat 9, so that no fuel from the pressure chamber 19 to the injection openings 11 can reach.
  • valve needle 5 then lifts with her Valve sealing surface 7 from the valve seat 9, and it flows Fuel from the pressure chamber 19 between the valve sealing surface 7 and the valve seat 9 through the injection openings 11 and is injected from there into the combustion chamber.
  • the Injection is either by increasing the closing force or by interrupting the fuel supply in the pressure chamber 19 ended.
  • the valve needle 5 slides, driven of the closing force, back into contact with valve seat 9 to its closed position and thus cuts off the fuel supply to the injection openings 11.
  • FIG 2 shows an enlargement of Figure 1 in the area of Valve seat 9.
  • the valve sealing surface 7 is divided into a first conical surface 30 and a second conical surface 32, with a ring edge at the transition of the two surfaces 34 is formed.
  • the opening angle of the first conical Surface 30 is smaller than the opening angle of the conical Valve seat 9, which in turn is smaller than that Opening angle of the second conical surface 32.
  • a first annular groove 36 is formed and one for this parallel second annular groove 38, both annular grooves 36, 38 with respect the longitudinal axis 8 of the bore 3 in a radial plane lie.
  • the first annular groove 36 is a flat countersink of the bore 3, so that a ring shoulder 37 is thereby formed becomes.
  • the ring edge 34 is in Closed position of the valve needle 5 either within this Section of the valve seat 9 or at the level of the second Ring groove 38 arranged.
  • valve needle 9 and the valve body 1 were ideally rigid, the valve needle 5 and the valve seat 9 would only turn on the ring edge 34 or at the transition of the valve seat 9 to touch the second annular groove 38. Because of the occurring elastic Deformations, the valve needle 5 lies on the entire Contact surface 10 on or at least for the most part the same, so that the occurring surface pressures reduce accordingly.
  • the contact surface 10 not over the area delimited by the ring grooves 36, 38 can grow out. This will also reduce the fuel pressure partial area of the first in the pressure chamber 19 conical surface 30 and thus also the opening pressure the valve needle 5, because in addition to the surface of the Pressure shoulder 13 also the corresponding partial surface of the valve sealing surface 7 is decisive.
  • the difference angle d 1 between the first conical surface 30 and the valve seat 9 is smaller than the difference angle d 2 between the second conical surface 32 and the valve seat 9, which corresponds to the so-called inverse seat angle difference. This additionally prevents the hammering of the ring edge 34 into the valve seat 9 from changing the area hydraulically acted upon by the fuel in the pressure chamber 19 and thereby causing a change in the opening pressure.
  • FIG. 1 A further exemplary embodiment is shown in FIG the same section as shown in Figure 2.
  • the Valve seat 9 extends up to the wall of the bore 3 first annular groove 36 is in the same way as the second annular groove 38 formed, but it has a greater depth and includes a larger area of the valve seat 9.
  • Die Contact surface 10 is in turn by the two ring grooves 36,38 limited, with the relatively large first annular groove 36 ensures that it is always connected to the pressure chamber 19 remains hydraulically connected.
  • the opening angle of the valve seat 9 is approximately 55 ° to 65 °, preferably approximately 60 °.
  • the corresponding differential angles d 1 and d 2 to the conical surfaces 30, 32 of the valve sealing surface 7 are a few degrees, preferably 0.5 ° to 3 °.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fuel-Injection Apparatus (AREA)
EP02017114A 2001-12-22 2002-07-30 Soupape d'injection de combustible pour moteurs à combustion interne Expired - Lifetime EP1321661B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10163908A DE10163908A1 (de) 2001-12-22 2001-12-22 Kraftstoffeinspritzventil für Brennkraftmaschinen
DE10163908 2001-12-22

Publications (3)

Publication Number Publication Date
EP1321661A2 true EP1321661A2 (fr) 2003-06-25
EP1321661A3 EP1321661A3 (fr) 2005-07-13
EP1321661B1 EP1321661B1 (fr) 2009-09-16

Family

ID=7710830

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02017114A Expired - Lifetime EP1321661B1 (fr) 2001-12-22 2002-07-30 Soupape d'injection de combustible pour moteurs à combustion interne

Country Status (4)

Country Link
US (1) US6789783B2 (fr)
EP (1) EP1321661B1 (fr)
JP (1) JP2003201938A (fr)
DE (2) DE10163908A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1700030A1 (fr) * 2003-12-17 2006-09-13 Robert Bosch Gmbh Corps de soupape presentant au niveau du siege de soupape une geometrie de cone multiple
EP1857668A1 (fr) * 2006-05-17 2007-11-21 Robert Bosch Gmbh Injecteur de carburant doté d'un double guide d'aiguille
CN105298706A (zh) * 2014-07-09 2016-02-03 江苏大学 燃油喷射装置的针阀组件
EP3156641A1 (fr) * 2015-10-14 2017-04-19 Continental Automotive GmbH Injecteur pour injection de fluides

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4197506B2 (ja) * 2004-08-31 2008-12-17 株式会社パイオラックス カットバルブ
US7360722B2 (en) * 2005-08-25 2008-04-22 Caterpillar Inc. Fuel injector with grooved check member
US7578450B2 (en) * 2005-08-25 2009-08-25 Caterpillar Inc. Fuel injector with grooved check member
US20070200011A1 (en) * 2006-02-28 2007-08-30 Caterpillar Inc. Fuel injector having nozzle member with annular groove
US8006715B2 (en) 2007-09-20 2011-08-30 Caterpillar Inc. Valve with thin-film coating
DE102008039920A1 (de) * 2008-08-27 2010-03-04 Continental Automotive Gmbh Düsenkörper, Düsenbaugruppe und Kraftstoffinjektor, sowie Verfahren zum Herstellen eines Düsenkörpers
JP2012007529A (ja) * 2010-06-24 2012-01-12 Toyota Motor Corp 燃料噴射弁
DE102013107390B4 (de) * 2013-07-12 2023-06-07 Svm Schultz Verwaltungs-Gmbh & Co. Kg Druckregelventil mit Regelelement
US9126223B2 (en) 2013-10-31 2015-09-08 Nordson Corporation Dispensing module and method for dispensing an adhesive
US9108214B2 (en) * 2013-10-31 2015-08-18 Nordson Corporation Dispensing module having a sealing zone and method for dispensing an adhesive
JP6355765B2 (ja) * 2015-01-30 2018-07-11 日立オートモティブシステムズ株式会社 燃料噴射弁
DE102016203028A1 (de) * 2016-02-26 2017-08-31 Bayerische Motoren Werke Aktiengesellschaft Kraftstoffinjektor
DE102016215637A1 (de) * 2016-08-19 2018-02-22 Robert Bosch Gmbh Kraftstoffeinspritzdüse
US10711902B2 (en) * 2017-01-31 2020-07-14 Fujikin Incorporated Flow dividing valve
CN108286626A (zh) * 2018-03-07 2018-07-17 烟台杰瑞石油装备技术有限公司 一种带有环形槽的阀座密封结构
CN113932496A (zh) * 2021-09-19 2022-01-14 青岛海尔空调器有限总公司 分液器、换热器、制冷循环系统、空调器

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19634933A1 (de) 1996-08-29 1998-03-05 Bosch Gmbh Robert Kraftstoffeinspritzventil für Brennkraftmaschinen
DE19942370A1 (de) 1999-09-04 2001-03-22 Bosch Gmbh Robert Einspritzdüse für Brennkraftmaschinen mit einer Ringnut in der Düsennadel

Family Cites Families (9)

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Publication number Priority date Publication date Assignee Title
US2822789A (en) * 1956-06-15 1958-02-11 Exxon Research Engineering Co Injection of heavy fuel into diesel engines and valve means therefor
ATE39546T1 (de) * 1985-10-22 1989-01-15 Voest Alpine Automotive Verfahren zum herstellen eines einspritzduesenkoerpers.
DE3624477A1 (de) * 1986-07-19 1988-01-28 Bosch Gmbh Robert Einspritzventil
DE19507188C1 (de) * 1995-03-02 1996-08-14 Bosch Gmbh Robert Kraftstoffeinspritzventil für Brennkraftmaschinen
DE19507171C1 (de) * 1995-03-02 1996-08-14 Bosch Gmbh Robert Kraftstoffeinspritzventil für Brennkraftmaschinen
DE19820513A1 (de) * 1998-05-08 1999-11-11 Mtu Friedrichshafen Gmbh Kraftstoffeinspritzdüse für eine Brennkraftmaschine
JP3567838B2 (ja) * 1999-04-26 2004-09-22 トヨタ自動車株式会社 燃料噴射ノズル
DE19931891A1 (de) * 1999-07-08 2001-01-18 Siemens Ag Kraftstoffeinspritzventil für eine Brennkraftmaschine
JP4221898B2 (ja) * 2000-02-29 2009-02-12 株式会社デンソー 燃料噴射ノズル

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19634933A1 (de) 1996-08-29 1998-03-05 Bosch Gmbh Robert Kraftstoffeinspritzventil für Brennkraftmaschinen
DE19942370A1 (de) 1999-09-04 2001-03-22 Bosch Gmbh Robert Einspritzdüse für Brennkraftmaschinen mit einer Ringnut in der Düsennadel

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1700030A1 (fr) * 2003-12-17 2006-09-13 Robert Bosch Gmbh Corps de soupape presentant au niveau du siege de soupape une geometrie de cone multiple
EP1857668A1 (fr) * 2006-05-17 2007-11-21 Robert Bosch Gmbh Injecteur de carburant doté d'un double guide d'aiguille
CN105298706A (zh) * 2014-07-09 2016-02-03 江苏大学 燃油喷射装置的针阀组件
CN105298706B (zh) * 2014-07-09 2017-09-29 江苏大学 燃油喷射装置的针阀组件
EP3156641A1 (fr) * 2015-10-14 2017-04-19 Continental Automotive GmbH Injecteur pour injection de fluides

Also Published As

Publication number Publication date
EP1321661A3 (fr) 2005-07-13
US20030132413A1 (en) 2003-07-17
DE50213847D1 (de) 2009-10-29
US6789783B2 (en) 2004-09-14
DE10163908A1 (de) 2003-07-03
EP1321661B1 (fr) 2009-09-16
JP2003201938A (ja) 2003-07-18

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