WO2009135712A1 - Injecteur de carburant et procédé de production associé - Google Patents

Injecteur de carburant et procédé de production associé Download PDF

Info

Publication number
WO2009135712A1
WO2009135712A1 PCT/EP2009/052688 EP2009052688W WO2009135712A1 WO 2009135712 A1 WO2009135712 A1 WO 2009135712A1 EP 2009052688 W EP2009052688 W EP 2009052688W WO 2009135712 A1 WO2009135712 A1 WO 2009135712A1
Authority
WO
WIPO (PCT)
Prior art keywords
nozzle needle
control rod
connecting element
fuel
fuel injector
Prior art date
Application number
PCT/EP2009/052688
Other languages
German (de)
English (en)
Inventor
Nadja Eisenmenger
Hans-Christoph Magel
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 WO2009135712A1 publication Critical patent/WO2009135712A1/fr

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/04—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00 having valves, e.g. having a plurality of valves in series
    • F02M61/10—Other injectors with elongated valve bodies, i.e. of needle-valve type
    • 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
    • F02M61/04—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00 having valves, e.g. having a plurality of valves in series
    • F02M61/10—Other injectors with elongated valve bodies, i.e. of needle-valve type
    • F02M61/12—Other injectors with elongated valve bodies, i.e. of needle-valve type characterised by the provision of guiding or centring means for valve bodies
    • 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
    • F02M61/168—Assembling; Disassembling; Manufacturing; Adjusting
    • 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
    • F02M2200/80—Fuel injection apparatus manufacture, repair or assembly
    • F02M2200/8084—Fuel injection apparatus manufacture, repair or assembly involving welding or soldering

Definitions

  • the invention relates to a fuel injector, in particular a common rail injector, for injecting fuel into a combustion chamber of an internal combustion engine according to the preamble of claim 1 and a method for producing a multi-part, a control rod and a nozzle needle comprehensive, injection valve element for a fuel injector according to the preamble of claim 12.
  • a designed as a common rail injector fuel injector is known, the injection valve element by means of a control valve (Servo-valve) can be controlled.
  • the injection valve element is designed in two parts in the known fuel injector, wherein a control chamber limiting control rod and a nozzle needle with a cooperating nozzle needle are operatively connected to each other via a hydraulic booster.
  • the known fuel injector is designed without a low-pressure stage, so that the leakage amount of the injector over other known injectors is significantly reduced.
  • a disadvantage is the complex structure of the hydraulic operative connection between the control rod and the nozzle needle.
  • the invention has for its object to provide a simply constructed fuel injector with a multipart injection valve element. Furthermore, the object is to propose a method for producing a multipart injection valve element for a fuel injector.
  • the invention is based on the idea firmly to connect the control rod and the nozzle needle using at least one connecting element. It is deliberately dispensed with a hydraulic coupler at the junction between the control rod and nozzle needle to simplify the production, in particular the assembly, and to realize a direct synchronization between the control rod and the nozzle needle.
  • fuel injector provided to connect the control rod and the nozzle needle using at least one connecting element permanently mechanically together to be able to transmit the forces occurring during operation directly.
  • a, in particular thin, preferably made of metal, connecting element has the advantage over a direct connection of control rod and nozzle needle that a certain elasticity of the connection of control rod and nozzle needle is realized in a simple manner, which in particular punctual, hard force courses in the operation of the Injectors are avoided.
  • the resulting, multi-part injection valve element behaves essentially like a one-piece injection valve element, but makes it possible, for example, to optimally respond to the respective requirements by a different choice of material of the control rod and the nozzle needle.
  • the nozzle needle to minimize wear for example, be formed of a harder material than the control rod.
  • control rod is additionally fixed by means of a connecting element to a guide member, which is preferably performed during the axial adjustment in an injector component.
  • the injector component is preferably a sleeve or a sleeve-shaped section of a plate element.
  • Particularly preferred is an embodiment of the fuel injector in which it has an integrated fuel storage volume, thereby reducing injection tolerances in the Mehrfacheinsprit- tion.
  • the connection point between the control rod and the nozzle needle with the connecting element directly in such a storage volume, that is surrounded by high pressure, arranged and a- xial adjustable within the storage volume.
  • the connecting element material and / or positively connected to the control rod and / or the nozzle needle can be realized for example by welding the connecting element to the control rod and / or the nozzle needle.
  • a material closure can be realized for example by welding the connecting element to the control rod and / or the nozzle needle.
  • the connecting element has been positively connected to the control rod and / or the nozzle needle by use of a so-called magnet forming process. It is particularly preferred to deliberately dispense with an additional material connection.
  • magnet forming the use of at least one magnet coil generates forming forces on the connecting element, preferably radially inwardly, which cause deformation of the connecting element such that the connecting element positively connects to the control rod and / or the nozzle needle.
  • the fixing of the connecting element on the control rod and the nozzle needle by magnetic forming has the great advantage that the deformation is carried out without contact, as a result of which punctual (asymmetrical) deformations, such as notches, etc., as in the case of mechanical forming inevitably occur.
  • the connecting element is deformed such that it engages behind both a connecting portion of the control rod and a connecting portion of the nozzle needle and thus realizes a permanent connection between the control rod and the nozzle needle.
  • the connecting element is designed as a connecting sleeve, which preferably surrounds the connecting region of the control rod and the nozzle needle radially on the outside.
  • an embodiment of the connecting element is preferred as a rotationally symmetric element.
  • the connecting sleeve for fixing the control rod to the nozzle needle can be moved over the nozzle needle or the control rod towards the connection point.
  • a weakened region is provided on the control rod and / or on the nozzle needle.
  • this involves at least one region of lower lateral bending stiffness, whereby a type of solid-body joint is formed, which permits elastic deformation of the control rod and / or the nozzle needle or of the injection valve element formed within certain limits.
  • the at least one weakened region is arranged axially adjacent to the connecting element.
  • the at least one weakening region is preferably realized by a peripheral groove provided on the outer circumference of the control rod or the nozzle needle.
  • a guide sleeve is used, which guides the nozzle needle.
  • this guide sleeve is supported via a compression spring on the nozzle needle, in particular on a shoulder of the nozzle needle from.
  • the guide sleeve is preferably arranged in the region of the free end of the nozzle needle, that is preferably in the immediate vicinity of the nozzle needle seat. At least it should be ensured that the guide sleeve in the lower, d. H. the nozzle needle seat facing, half of the nozzle needle is, more preferably in the range of the lower third.
  • control rod and nozzle needle is particularly suitable for injectors in which the injection valve element is longer than 100 mm.
  • the fuel injector is particularly preferably an injector without a low-pressure stage, wherein the connecting element, preferably completely surrounded by high pressure, is arranged in an integral fuel reservoir of the fuel injector.
  • the invention also leads to a method for producing a multipart injection valve element comprising a control rod and a nozzle needle.
  • the control rod and the nozzle needle are permanently fixed together using at least one connecting element.
  • the connecting element is preferably connected to the control rod and / or the nozzle Needle material and / or positively connected. It is particularly preferred to fix the connecting element exclusively in a form-fitting manner with the control rod and the nozzle needle, particularly preferably by magnetic forming.
  • FIG. 1 shows a fuel injector with a two-part injection valve element, wherein a control rod and a nozzle needle are positively connected to one another via a connecting element and
  • FIG. 2 shows an alternative embodiment of a fuel injector, in which the multipart injection valve element is guided by means of a guide sleeve.
  • Fig. 1 designed as a common rail injector fuel injector 1 is shown for injecting fuel into a combustion chamber, not shown, of a likewise not shown internal combustion engine of a motor vehicle.
  • a high pressure pump 2 delivers fuel from a reservoir 3 in a high-pressure fuel storage 4 (Rail). In this fuel, especially diesel or gasoline, under high pressure, of about 2000 bar in this embodiment, stored.
  • a high-pressure fuel storage 4 especially diesel or gasoline
  • the supply line 5 opens into a pressure chamber 6 (high pressure area) of the fuel injector 1, which serves as a mini-rail, so as an integral fuel storage. From the pressure chamber 6, the fuel flows in an injection process directly into the combustion chamber of the internal combustion engine.
  • the fuel Inj ector 1 is connected via an injector return port 7 to a return line 8 and via this to the reservoir 3. Via the return line 8, a later to be explained control amount of fuel from the fuel injector 1 to flow to the reservoir 3 and are fed from there from the high pressure circuit again.
  • a multipart injection valve element 10 is received and adjustable in the axial direction.
  • the injection valve element 10 consists of an (upper) control rod 11 and a (lower) nozzle needle 12, wherein the control rod 11 is fixed to the nozzle needle 12 via a sleeve-shaped connecting element 13 which is held in a form-fitting manner on the control rod 11 and the nozzle needle 12.
  • the nozzle needle 12 is guided on its outer circumference in a central region on the inner periphery of a bore 14 in a nozzle body 15 which is axially adjacent to the injector body 9.
  • the nozzle body 15 is clamped by means of a union nut, not shown, with the injector 9.
  • the nozzle needle 12 of the injection valve element 10 has at its tip 16 a closing surface 17, with which the injection valve element 10 can be brought into a tight contact with a nozzle needle seat 18 formed within the nozzle body 15.
  • a closing surface 17 with which the injection valve element 10 can be brought into a tight contact with a nozzle needle seat 18 formed within the nozzle body 15.
  • the injection valve element 10 lifted off the nozzle needle seat 18, fuel from the nozzle chamber 6 formed by in a guide portion 20 on the outer circumference of the nozzle needle 12 by polished axial channels 21 in a lower plane in the drawing, radially formed between the nozzle needle 12 and the nozzle body 15, annulus 22 to flow past the nozzle needle seat 18 to the nozzle hole assembly 19 and there are injected substantially under high pressure (rail pressure) standing in the combustion chamber.
  • the axial channels 21 are preferably designed as throttle channels in order to realize a slight throttling of the fuel on the way to the nozzle hole arrangement 19. As a result, the closing speed of the injection valve element 10 is optimized.
  • the entire injection valve element 10 which has a length of more than 100 mm and is accommodated directly in the pressure chamber 6, no low-pressure stage assigned, so that via the return line 8 during operation of the fuel injector. 1 minimized flowing fuel quantity and thereby the efficiency of the fuel injector 1 is optimized.
  • a control chamber 26 is limited, which extends over a radially in the sleeve-shaped portion 24 of the plate member 25 extending inlet throttle 27 with high-pressure fuel the pressure chamber 6 is supplied.
  • the sleeve-shaped section 24 with the control chamber 26 enclosed therein is completely surrounded on the outside by high-pressure fuel, thus protruding into the pressure chamber 6, so that an annular guide gap 28 is comparatively fuel-tight radially between the sleeve-shaped section 24 and the control rod 11 ,
  • the control chamber 26 is connected via a arranged in the plate member 25, drain passage 29 with cavitating discharge throttle 30 with a valve chamber 31, the radially outward of a, adjustable in the axial direction, valve sleeve 32 of a pressure-balanced in the axial direction of the control valve 33 (servo Valve) is limited.
  • fuel can flow into a low-pressure region 34 of the fuel injector 1 and from there to the injector return port 7 when the control valve 33 is open.
  • the valve sleeve 32 formed integrally with an anchor plate 35 is lifted off its control valve seat 36 formed on the plate element 25.
  • an electromagnetic actuator 37 is provided with an electromagnet 38, which cooperates with the armature plate 35 arranged in an armature space 35 and consequently also with the valve sleeve 32.
  • an electromagnetic actuator 37 may also be provided a piezoelectric actuator.
  • valve sleeve 32 When current flows through the electromagnetic actuator 37, the valve sleeve 32 lifts from its arranged on the plate member 25, formed in this embodiment as a flat seat, control valve seat 36 from.
  • the flow cross sections of the inlet throttle 27 and the outlet throttle 30 are matched to one another such that when the control valve 33 is open, a net outflow of fuel (control quantity) from the control chamber 26 via the valve chamber 31 into the low pressure region 34 of the fuel injector 1 and from there flows via the Injektor Weglaufan gleich 7 and the return line 8 into the reservoir 3.
  • the pressure in the control chamber 26 drops rapidly, whereby the injection valve element 10 lifts off from its nozzle needle seat 18, so that fuel can flow out of the pressure chamber 6 through the nozzle hole arrangement 19.
  • the energization of the electromagnetic actuator 37 is interrupted, whereby the valve sleeve 32 is adjusted by means of a control spring 40 which is supported on the armature plate 35 in the drawing plane down to its control valve seat 36.
  • the fuel flowing in through the inlet throttle 27 into the control chamber 26 ensures rapid pressure increase in the control chamber 26 and thus a closing force acting on the injection valve element 10.
  • the resulting closing movement of the injection valve element 10 is assisted by a closing spring 41, which at one end abuts a peripheral collar 42 of the injection valve element 10 and at the other end at the lower in the drawing plane End face 43 of the sleeve-shaped portion 24 of the plate member 25 is supported.
  • a pressure pin 44 is received centrally within the valve sleeve 32. This is based on in-service fuel injector 1 by the pressure in the valve chamber 31 in the axial direction upwards on an injector cover 45 from.
  • the task of the axially adjustable pressure pin 44 is to seal the valve chamber 31 in the axial direction upwards. In its in the drawing plane upper portion of the pressure pin 44 is arranged centrally within the control spring 40.
  • the nozzle needle 12 is made shorter than the control rod 11.
  • the nozzle needle 12 is supported at a right angle to its longitudinal central axis arranged nozzle needle contact surface 46 on a parallel extending control rod contact surface 47.
  • the orientation of the control rod 11 and the nozzle needle 12 to each other in the connection process can be done via the formation of the contact surfaces (nozzle needle contact surface 46 and control rod contact surface 47) and / or via the connecting element 13. 1, the sleeve-shaped connecting element 13 engages around a (lower) connecting portion 48 of the control rod 11 and an (upper) connecting portion 49 of the nozzle needle 12.
  • the connecting portions 48, 49 taper conically on the sides facing away from each other , It can be seen that the connecting element 13 engages in a circumferential groove 50 in the nozzle needle 12.
  • the circumferential groove 50 forms a weakening region 51 of the nozzle needle 12 with little lateral bending stiffness immediately adjacent to the Connecting element 13. This allows a certain elastic deformation of the injection valve element 10, whereby tilting of the injection valve element 10 during operation of the fuel injector 1 is avoided.
  • control rod 11 and the nozzle needle 12 are fixed to each other exclusively via a positive connection achieved by means of the connecting element 13.
  • the connecting element 13 engages behind both the connecting portion 48 of the control rod 11 and the axially immediately adjacent connecting portion 49 of the nozzle needle 12 by the connecting element abuts the conically tapering Endab- sections of the connecting portions 48, 49, the control rod 11 and nozzle needle 12 biased against each other, so that a permanent axial connection force acts on the components of the injection valve element 10.
  • the rotationally symmetrical connecting element 13 is a thin metal sleeve (connecting sleeve) that has been converted from an originally circular-cylindrical shape by magnetic forming into the shape shown, which engages behind the connecting sections 48, 49. Due to the small thickness of the connecting element 13 and the choice of the metallic material, a certain elasticity of the connection between the control rod 11 and the nozzle needle 12 is achieved, which is optimized for the force distribution or force transmission between the control rod 11 and the nozzle needle 12 Control rod 11 in their movement immediately follows, affects.
  • Fig. 2 an alternative embodiment of a fuel Inj ector 1 is shown. The embodiment shown corresponds in its mode of operation to the exemplary embodiment according to FIG. 1, so that only the differences from the embodiment shown in FIG. 1 will be explained below. With regard to similarities, reference is made to the preceding description of the figures and to FIG.
  • a further difference of the fuel injector 1 shown in Fig. 2 to the embodiment shown in Fig. 1 is that the nozzle needle 12 is not guided directly on the nozzle body 15, but on a guide sleeve 54, the nozzle needle 12 in its lower Be - Rich encloses radially on the outside.
  • the guide sleeve 54 is pressed by means of a compression spring 55, which is supported on a (lower) annular shoulder 56 of the nozzle needle 12, in the drawing plane down against an oblique annular surface 57 of the nozzle body 15 radially adjacent to the nozzle needle seat 18.
  • the guide sleeve 54 is located in the annular space 22 radi al between the nozzle body 15 and the nozzle needle 12. Fuel can flow through provided in the guide sleeve 54 radial channels 58 to the nozzle hole assembly 19. In this case, these radial channels 58 can be designed as throttles with preferably a low throttle effect, in order to optimize the closing speed of the injection valve element 10.
  • control rod 11 can be connected on the side facing away from the nozzle needle 12 via a connecting element 13 with a guided in the lower sleeve-shaped portion 24 guide member 59, which then, unlike in Figs. 1 and 2, as formed by the control rod 11 separate component.

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

Abstract

L'invention concerne un injecteur de carburant (1), en particulier un injecteur à rampe commune, destiné à injecter du carburant dans une chambre de combustion d'un moteur à combustion interne, comprenant un élément de soupape d'injection (10), en plusieurs parties, pouvant passer d'une position ouverte à une position fermée, et comprenant une tige de commande (11) et une aiguille d'injecteur (12). Selon l'invention, la tige de commande (11) et l'aiguille d'injecteur (12) sont fixées l'une sur l'autre par un élément de fixation (13). L'invention concerne également un procédé de production associé.
PCT/EP2009/052688 2008-05-06 2009-03-06 Injecteur de carburant et procédé de production associé WO2009135712A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE200810001601 DE102008001601A1 (de) 2008-05-06 2008-05-06 Kraftstoff-Injektor sowie Herstellungsverfahren
DE102008001601.2 2008-05-06

Publications (1)

Publication Number Publication Date
WO2009135712A1 true WO2009135712A1 (fr) 2009-11-12

Family

ID=40863403

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2009/052688 WO2009135712A1 (fr) 2008-05-06 2009-03-06 Injecteur de carburant et procédé de production associé

Country Status (2)

Country Link
DE (1) DE102008001601A1 (fr)
WO (1) WO2009135712A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2313640B1 (fr) * 2008-08-11 2016-08-10 Robert Bosch GmbH Organe de soupape d'injection

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102014226407A1 (de) 2014-12-18 2016-06-23 Robert Bosch Gmbh Einspritzdüse für Kraftstoffe

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19815892A1 (de) * 1997-04-17 1998-10-22 Nippon Soken Kraftstoffeinspritzdüse
DE102006029393A1 (de) * 2006-06-27 2008-01-03 Robert Bosch Gmbh Injektor

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006012078A1 (de) 2005-11-15 2007-05-16 Bosch Gmbh Robert Kraftstoff-Einspritzvorrichtung für eine Brennkraftmaschine mit Kraftstoff-Direkteinspritzung

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19815892A1 (de) * 1997-04-17 1998-10-22 Nippon Soken Kraftstoffeinspritzdüse
DE102006029393A1 (de) * 2006-06-27 2008-01-03 Robert Bosch Gmbh Injektor

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2313640B1 (fr) * 2008-08-11 2016-08-10 Robert Bosch GmbH Organe de soupape d'injection

Also Published As

Publication number Publication date
DE102008001601A1 (de) 2009-11-12

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