EP0781915A1 - Injecteur de carburant - Google Patents

Injecteur de carburant Download PDF

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Publication number
EP0781915A1
EP0781915A1 EP96203324A EP96203324A EP0781915A1 EP 0781915 A1 EP0781915 A1 EP 0781915A1 EP 96203324 A EP96203324 A EP 96203324A EP 96203324 A EP96203324 A EP 96203324A EP 0781915 A1 EP0781915 A1 EP 0781915A1
Authority
EP
European Patent Office
Prior art keywords
cylindrical
fuel
tubular
bore
pole
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.)
Withdrawn
Application number
EP96203324A
Other languages
German (de)
English (en)
Inventor
Gary Michael Zdyb
Michael Brian Lavan
Otto Muller-Girard, Jr.
Harrie William Ii Bonnah
Brent Jack Wahba
Jay Keith Sofianek
Chester Henry Ciesinski
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.)
Motors Liquidation Co
Original Assignee
Motors Liquidation Co
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 Motors Liquidation Co filed Critical Motors Liquidation Co
Publication of EP0781915A1 publication Critical patent/EP0781915A1/fr
Withdrawn legal-status Critical Current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
    • F02M51/00—Fuel-injection apparatus characterised by being operated electrically
    • F02M51/06—Injectors peculiar thereto with means directly operating the valve needle
    • F02M51/061—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means
    • F02M51/0625—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures
    • F02M51/0664—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of mobile armatures having a cylindrically or partly cylindrically shaped armature, e.g. entering the winding; having a plate-shaped or undulated armature entering the winding
    • 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
    • F02M51/00—Fuel-injection apparatus characterised by being operated electrically
    • F02M51/06—Injectors peculiar thereto with means directly operating the valve needle
    • F02M51/061—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means
    • F02M51/0614—Injectors peculiar thereto with means directly operating the valve needle using electromagnetic operating means characterised by arrangement of electromagnets or fixed armature
    • 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
    • F02M61/166—Selection of particular materials

Definitions

  • the invention relates to fuel injectors for delivery of fuel to the intake system of an internal combustion engine.
  • the coil windings in the solenoid actuator be protected from excessive exposure to fuel in order to assure reliable performance. Chemical constituents in the fuel degrade the insulation and metal of the windings which can, over time result in degraded injector operation.
  • elastomeric seals between injector components and a fuel resistant bobbin material is intended to prevent the passage of fuel to the coil windings. It is known to extend the upper pole piece to a location below that of the coil assembly where it may be used to establish a seal with the injector body. Such a design may be effective for sealing of the coil assembly from the fuel supply, however the efficiency of the magnetic circuit is not optimized due to the placement of the working air gap below the coil assembly. Non-optimal placement of the working air gap may result in excess magnetic flux leakage between the pole piece and parallel injector body surfaces which reduces the flux acting across the working air gap to move the armature.
  • a fuel injector for use in an internal combustion engine, having an actuator assembly which seals the coil against exposure to the fuel while optimizing the location of the working air gap relative to the coil.
  • a feature of the invention is to provide a pole piece having its lower, working surface disposed intermediate the ends of the coil bobbin.
  • a non-magnetic, tubular extension member is fixed to the lower pole piece, adjacent the working surface and extends the pole piece beyond the coil to seal. A seal is established, between the non-magnetic extension and the injector body, against ingress of fuel into the coil assembly.
  • An additional feature of the invention may be to provide a reduced diameter, annular region intermediate of the ends of the pole piece tubular extension.
  • the annular region may function as a bearing surface for an armature disposed for reciprocal movement relative to the working surface of the pole piece.
  • an electromagnetic fuel injector designated generally as 10, includes as major components thereof a body 12, a nozzle assembly 14, a valve member 16 and a solenoid actuator assembly 18 used to control the movement of the valve member 16.
  • the body 12 is of cylindrical, hollow tubular configuration and is of such external shape as to permit direct insertion, if desired, of the injector 10 into a socket provided for this purpose in an engine intake manifold, not shown.
  • the body 12, Figure 3 includes an enlarged upper solenoid case portion 20 and a lower end, nozzle case portion 22 of reduced internal and external diameter relative to the solenoid portion 20.
  • An internal cylindrical cavity is formed in the body 12 by a stepped bore therethrough that is substantially coaxial with the axis 26 of the body.
  • the cavity 24 includes a cylindrical upper wall 28, a cylindrical intermediate wall 30 and a cylindrical lower wall 32.
  • Wall 30 is of a reduced diameter relative to upper and lower wall portions 28 and 32, respectively.
  • Solenoid assembly 18 is disposed within the enlarged upper solenoid case portion 20 and includes a spool-like, tubular bobbin 34 supporting a wound wire solenoid coil 36.
  • the solenoid assembly 18 is positioned within the upper case portion 20 adjacent shoulder 38 which extends between cylindrical upper wall 28 and the intermediate wall 30.
  • a resilient sealing member such as o-ring 40 is disposed between a downwardly oriented (as viewed in the figures) cylindrical extension 42 located about the inner diameter of the tubular bobbin 34 and a seal shoulder 44 in the cylindrical intermediate wall 30.
  • the bobbin 34 is provided with a central through bore 46 configured to encircle the lower, reduced diameter portion 48 of pole piece 50.
  • a pair of terminal leads 52, Figure 1 are operatively connected at one end (not shown) to the solenoid coil 36 and each such lead has its second end extending upwardly through an outer, overmolded casing 54, described in further detail below, to terminate in a terminal socket 56, for connection of the fuel injector to a suitable source of electrical power in a manner well known in the art.
  • Pole piece 50 includes an upper cylindrical portion 58, a centrally located circular, radial flange portion 60 and the lower reduced diameter cylindrical pole 48.
  • the circular, radial flange portion 60 is slidably received at its outer peripheral edge within the cylindrical upper wall 28 of the body 12 to thereby close the enlarged upper solenoid case portion 20 of the body 12 and retain the solenoid assembly 18 therein.
  • the pole piece 50 is axially retained within the upper cylindrical portion of the body 12 as by having its flange portion welded or otherwise suitably bonded to the shoulder 62 along the upper, opened end of wall 28.
  • Lower pole 48 is of a suitable exterior diameter so as to be slidably received in the central through bore 46 that extends coaxially through the coil bobbin 34 and of a suitable axial length to extend the working surface 66 to an optimum location intermediate the ends of the coil central through bore 46. Location of the working surface 66 of the pole piece 48 centrally of the coil axial length is important for maximization of magnetic efficiency.
  • a cylindrical tube 64 of non-magnetic material such as stamped or drawn stainless steel or other suitable material, Figures 3 and 4.
  • the tube may be welded, bonded or otherwise sealed to the lower pole piece 48 so as to prevent fuel penetration of the joint between the tube 64 and the pole.
  • the tube 64 extends axially downwardly beyond the lower end, or working surface 66 of the lower cylindrical pole 48, to a location substantially downstream of the pole.
  • the outer surface 68 of the non-magnetic tube 64 interfaces with resilient sealing member 40, seated between the lower end of the coil bobbin extension 42 and seal shoulder 44 of the body 12, thereby establishing a seal between the central, fuel passage 70 extending the length of fuel injector 10 and the solenoid assembly 18.
  • the cylindrical, non-magnetic tube 64 operates to extend the pole piece 48 below the coil 36 to establish an efficient seal with the injector body 12 while providing an efficient magnetic circuit design by allowing working surface 66 to be located optimally within the coil through bore 46.
  • the pole piece 50 combines with non-magnetic, cylindrical tube 64 and injector body 12 to define a dry coil design which effectively isolates the coil windings 36 from fuel exposure. In the event of fuel leakage past the seal member 40, the fuel is prevented from escaping the injector body, such as by a welded seal 63 at the interface of pole piece flange 60 and shoulder 62 of injector body upper case portion 20.
  • the pole piece 50 in the construction illustrated, is also provided with an upwardly extending cylindrical boss 58.
  • the boss 58 is configured to receive an axially upwardly extending, deep drawn fuel inlet tube 74.
  • the inlet tube has a first inlet end 76 having a flanged end portion 78 extending from the upper end thereof.
  • the deep drawn fuel inlet tube is preferably formed using sheet stock which results in a final product having a nominal wall thickness.
  • the fuel inlet tube 74 is fixed to the pole piece 50 and is overmolded to define upper housing 54, using a suitable encapsulant material which, as described above, also includes an integral terminal socket 56 with leads 52.
  • the encapsulant allows the inner diameter of the fuel inlet tube to be tightly controlled while the outer diameter of the upper housing portion of injector 10 is controlled during the molding of the encapsulant.
  • An upper seal shoulder 86 formed in the overmolded housing 54 is axially spaced from the tube flange 78 to define an annular seal groove 88 configured to carry a resilient sealing member such as o-ring 90 for leak free attachment to a source of pressurized fuel, not shown.
  • radially inwardly extending dimples 92 are disposed for engagement with the flanged portion 94 of the injector fuel filter assembly 96.
  • the dimples 92 inhibit undesirable downstream translation of the filter assembly 96 in the fuel inlet tube 74.
  • the nozzle assembly 14 includes a nozzle body 98 having a cup-shaped, tubular configuration with a stepped upper shoulder 100 for receiving a sealing member such as o-ring 102.
  • the sealing member 102 is disposed between the shoulder 100 on the outer surface of the nozzle body 98 and, the shoulder 106 which extends between the intermediate wall 30 and the lower wall 32 of the lower end nozzle case portion 22 of the body 12, thereby establishing a seal against leakage at the interface of the nozzle assembly 14 and the body 12.
  • the nozzle body 98 includes a series of external threads 108 which engage corresponding internal threads 110 in the lower wall 32 of the body 12 providing axial adjustability of the nozzle body within the injector body.
  • An internal cylindrical cavity 112 in the nozzle body 98 is defined by an inner cylindrical wall 114 which extends from the open, upper end of the nozzle body to terminate in an annular, frustoconical valve seat 116 disposed about an axially aligned, fuel discharge opening 118 at the lower end thereof.
  • the cylindrical cavity 112 operates as a fuel supply repository within the nozzle assembly 12.
  • the director plate 122 is formed of thin sheet stock and includes fuel directing openings 124 extending from the upstream side 126 to the downstream side 128. Fuel passing through the fuel discharge opening 118 in the valve seat 116 is delivered to the upstream side, or face 126 of the director plate 122 where it is distributed across the face to the fuel openings 124.
  • the openings 124 are oriented in a predetermined configuration which will generate, in the discharged fuel, a desired spray configuration.
  • a cylindrical retainer sleeve 130 is also engaged over the lower end of nozzle body 98.
  • the retainer includes an upper annular shoulder 132 which defines, with shoulder 134 of body 12, an annular groove 136 for the placement of resilient sealing member 138.
  • the lower, downstream end 140 of the retainer sleeve 130 extends beyond the downstream side 128 of the director plate 122 and functions to protect the director plate 122 from contact with surfaces which could damage the plate by altering the precise alignment of the fuel directing orifices 124.
  • the cylindrical retainer sleeve 130 is preferably constructed of a durable, temperature resistant plastic such as nylon and is snapped over the lower end, nozzle case portion 22 of the body 12 where small annular bead 142 on the inner wall of the cylindrical retainer sleeve 130 engages a corresponding groove 141 on the outer wall of the nozzle case portion 22 to fix the retainer sleeve against axial movement off of the injector 10.
  • valve member 16 it includes a tubular armature 146 and a valve element 148, the latter being made of, for example, a spherical ball having a predetermined radius, which is welded to the lower annular end 150 of the tubular armature 146.
  • the radius of the valve element 148 is chosen for seating engagement with the valve seat 116.
  • the tubular armature 146 is formed with a predetermined outside diameter so as to be loosely slidable within the non-magnetic cylindrical tube 64 received about and extending from the lower pole piece 48.
  • the tube 64 includes an inner cylindrical wall 154 which extends coaxially with the axis 26 of the injector 10 along which the valve member 16 is aligned for reciprocal movement.
  • FIG. 5A,5B and 6A,6B illustrate two embodiments of the tube 64 and armature bearing 156.
  • the bearing may be defined by a region of increased thickness 158 in the tube 64', as illustrated in Figures 6A,6B, or by a mechanically reduced diameter portion 160, as is illustrated in Figures 5A,5B.
  • the armature tube bearing 156,156' is formed as a radius "R" such that the axially intermediate portion of the bearing 156 has the smallest internal diameter.
  • the radiused bearing surface prevents the tubular armature 146 from resting on, or moving across a bearing edge which would likely cause premature wear and binding of the valve member 16 while accommodating some misalignment between the tubular extension 64 and the tubular armature 146.
  • valve guide 164 Positioned within the cylindrical cavity 112 of the nozzle body 98, adjacent the valve seat 116, is an annular valve guide 164.
  • the valve guide 164 has a centrally disposed guide opening 165 that extends about the valve ball member 148 and is operable to guide the member as it moves reciprocally into and out of engagement with the valve seat 116.
  • Fuel openings 166 extend through the valve guide 164 at circumferentially spaced locations about the annulus to allow fuel to move freely from the fuel collecting internal cylindrical cavity 112 to the valve seat 116.
  • the armature bearing 156 in tube 64 and the annular valve guide 164 cooperate to control the movement of the valve member 16, in the longitudinal direction, within the injector 10.
  • the valve member element 148 of valve member 16 is normally biased into a closed, seated engagement with the valve seat 116 by a biasing member such as valve return spring 168 of predetermined spring force which is inserted into the upstream end of the tubular armature 146.
  • the first end of the spring 168 seats against shoulder 172 which is located intermediate the ends of the armature tube while the second end of the spring 168 seats against the lower end 176 of calibration sleeve 178 inserted into the central, through bore 51 of pole piece 50.
  • the calibration sleeve is moved axially towards the valve seat to increase the spring preload exerted on the valve member 16 in the direction of the valve seat 116. Withdrawal of the calibration sleeve 178 lessens the spring preload on the valve member 16.
  • the calibration sleeve 178 is fixed in position within the pole piece 50 through application of a staking process in which a mechanical staking tool (not shown) is inserted into openings 182 in the overmolded housing 54.
  • the staking tool moves to deform the upper cylindrical portion 58, Figure 2, of the pole piece 50 radially inwardly 183 about the sleeve 178 thereby fixing the sleeve from axial movement.
  • a working air gap 184 is defined between the working surface 186 at the upper end of armature tube 146 of the valve member 16 and the working surface 66 at the lower end of the pole piece 50.
  • the tubular armature 146 and associated valve element 148 is drawn upwardly, off of the valve seat 116, by the action of the magnetic flux field operating across the working air gap 184 which operates against the bias of the spring member 168 to close the working air gap 184.
  • Fuel exiting the valve seat 116 is distributed onto the upstream side 126 of the fuel director plate 122 where it is distributed to the fuel director orifices 124 passing through the plate, for discharge from the fuel injector 10.
  • Deenergization of the solenoid assembly 18 allows the field within the magnetic circuit defined by the pole piece 50, the body 12, and the armature 146 to collapse thereby allowing the valve member return to the closed position against the valve seat 116 under the bias of the spring member 168 to stop the flow of fuel therethrough.
EP96203324A 1995-12-26 1996-11-26 Injecteur de carburant Withdrawn EP0781915A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US57698495A 1995-12-26 1995-12-26
US576984 1995-12-26

Publications (1)

Publication Number Publication Date
EP0781915A1 true EP0781915A1 (fr) 1997-07-02

Family

ID=24306816

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96203324A Withdrawn EP0781915A1 (fr) 1995-12-26 1996-11-26 Injecteur de carburant

Country Status (2)

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EP (1) EP0781915A1 (fr)
MX (1) MX9606148A (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1442830A1 (fr) * 2003-01-28 2004-08-04 Hitachi, Ltd. Pièce composite et son procédé de production; soupape d'injection de carburant avec cette pièce composite et son procédé de production
WO2009053221A1 (fr) * 2007-10-18 2009-04-30 Robert Bosch Gmbh Soupape d'injection de carburant
WO2009053196A1 (fr) * 2007-10-18 2009-04-30 Robert Bosch Gmbh Soupape d'injection de carburant
CN103842699A (zh) * 2011-09-28 2014-06-04 纳博特斯克有限公司 电磁驱动器
CN112673165A (zh) * 2018-09-12 2021-04-16 德尔福汽车系统卢森堡有限公司 极片保持和插入方法

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2008830A1 (de) * 1969-02-25 1970-08-27 Soclete Industrielle de Brevets et d'Etudes S.I.B.E., Neuilly-sur-Seine (Frankreich) Vorrichtung zur Speisung von Verbrennungsmotoren mit Brennstoff
EP0215527A1 (fr) * 1985-09-19 1987-03-25 WEBER S.r.l. Electro-injecteur d'alimentation de combustible pour moteurs à combustion interne et son procédé de fabrication
DE3905992A1 (de) * 1989-02-25 1989-09-21 Mesenich Gerhard Elektromagnetisches hochdruckeinspritzventil
DE3942306A1 (de) * 1989-12-21 1991-06-27 Bosch Gmbh Robert Elektromagnetisch betaetigbares ventil
DE4310819A1 (de) * 1993-04-02 1994-10-06 Bosch Gmbh Robert Verfahren zur Einstellung eines Ventils
DE19507285A1 (de) * 1994-03-03 1995-09-07 Nippon Denso Co Fluideinspritzdüse

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2008830A1 (de) * 1969-02-25 1970-08-27 Soclete Industrielle de Brevets et d'Etudes S.I.B.E., Neuilly-sur-Seine (Frankreich) Vorrichtung zur Speisung von Verbrennungsmotoren mit Brennstoff
EP0215527A1 (fr) * 1985-09-19 1987-03-25 WEBER S.r.l. Electro-injecteur d'alimentation de combustible pour moteurs à combustion interne et son procédé de fabrication
DE3905992A1 (de) * 1989-02-25 1989-09-21 Mesenich Gerhard Elektromagnetisches hochdruckeinspritzventil
DE3942306A1 (de) * 1989-12-21 1991-06-27 Bosch Gmbh Robert Elektromagnetisch betaetigbares ventil
DE4310819A1 (de) * 1993-04-02 1994-10-06 Bosch Gmbh Robert Verfahren zur Einstellung eines Ventils
DE19507285A1 (de) * 1994-03-03 1995-09-07 Nippon Denso Co Fluideinspritzdüse

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1442830A1 (fr) * 2003-01-28 2004-08-04 Hitachi, Ltd. Pièce composite et son procédé de production; soupape d'injection de carburant avec cette pièce composite et son procédé de production
WO2009053221A1 (fr) * 2007-10-18 2009-04-30 Robert Bosch Gmbh Soupape d'injection de carburant
WO2009053196A1 (fr) * 2007-10-18 2009-04-30 Robert Bosch Gmbh Soupape d'injection de carburant
JP2011501025A (ja) * 2007-10-18 2011-01-06 ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツング 燃料噴射弁
CN103842699A (zh) * 2011-09-28 2014-06-04 纳博特斯克有限公司 电磁驱动器
CN112673165A (zh) * 2018-09-12 2021-04-16 德尔福汽车系统卢森堡有限公司 极片保持和插入方法

Also Published As

Publication number Publication date
MX9606148A (es) 1997-06-28

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