EP2020045A1 - Système pourvu d'un piézoactionneur traversé par des milieux liquides - Google Patents

Système pourvu d'un piézoactionneur traversé par des milieux liquides

Info

Publication number
EP2020045A1
EP2020045A1 EP07729043A EP07729043A EP2020045A1 EP 2020045 A1 EP2020045 A1 EP 2020045A1 EP 07729043 A EP07729043 A EP 07729043A EP 07729043 A EP07729043 A EP 07729043A EP 2020045 A1 EP2020045 A1 EP 2020045A1
Authority
EP
European Patent Office
Prior art keywords
sleeve
actuator
arrangement according
space
arrangement
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Withdrawn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
EP07729043A
Other languages
German (de)
English (en)
Inventor
Nadja Eisenmenger
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 EP2020045A1 publication Critical patent/EP2020045A1/fr
Withdrawn legal-status Critical Current

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
    • F02M51/00—Fuel-injection apparatus characterised by being operated electrically
    • F02M51/06—Injectors peculiar thereto with means directly operating the valve needle
    • F02M51/0603—Injectors peculiar thereto with means directly operating the valve needle using piezoelectric or magnetostrictive operating means
    • 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
    • F02M47/00—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure
    • F02M47/02—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure of accumulator-injector type, i.e. having fuel pressure of accumulator tending to open, and fuel pressure in other chamber tending to close, injection valves and having means for periodically releasing that closing pressure
    • F02M47/027—Electrically actuated valves draining the chamber to release the closing pressure
    • 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
    • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
    • F02M63/0012—Valves
    • F02M63/0057—Means for avoiding fuel contact with valve actuator, e.g. isolating actuators by using bellows or diaphragms
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/80—Constructional details
    • H10N30/88—Mounts; Supports; Enclosures; Casings
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N30/00—Piezoelectric or electrostrictive devices
    • H10N30/80—Constructional details
    • H10N30/88—Mounts; Supports; Enclosures; Casings
    • H10N30/883—Additional insulation means preventing electrical, physical or chemical damage, e.g. protective coatings

Definitions

  • the invention relates to an arrangement with a flow around the liquid media piezoelectric actuator, for example in a piezoelectric actuator in injection systems for internal combustion engines, according to the generic features of the main claim.
  • a piezoelectric element can be used in such a way that, by utilizing the so-called piezoelectric effect, it is possible to control the needle stroke of a valve or the like.
  • the piezoelectric element is constructed of a material having a suitable crystal structure such that upon application of an external electrical voltage, a mechanical reaction of the piezoelectric element takes place, which represents a pressure or tension in a predeterminable direction as a function of the crystal structure and the contact regions of the electrical voltage.
  • Such piezoelectric actuators are suitable, for example, for applications in which lifting movements take place under high operating forces and high clock frequencies.
  • such a piezoelectric actuator is known as part of a piezoelectric injector from DE 10026005 A1, which is used to control the nozzle needle in injectors for the injection of
  • Fuel can be used in the combustion chamber of an internal combustion engine.
  • this piezoelectric actuator is a piezoelectric element as Stack composed of several electrically coupled together piezoceramic layers, which is held under bias between two stops. Each piezoceramic layer is enclosed as a piezoelectric layer between two internal electrodes, via which an electrical voltage can be applied externally. Due to this electrical voltage, the piezoceramic layers then each carry out small strokes in the direction of the potential drop, which add up to the total stroke of the piezoactuator. This total stroke is variable by the amount of voltage applied and can be transferred to a mechanical actuator.
  • These common rail injectors can be constructed in such a way that a nozzle needle controlled directly by the piezoactuator is present, wherein the piezoactuator is directly surrounded by the rail pressure of the fuel and only a hydraulic coupling space is provided between the nozzle needle and the piezoactuator.
  • the rail pressure can be up to 2000 bar, to which the ceramic of the piezoelectric element is exposed. Since the piezoceramic often has a certain porosity or even fine cracks on the surface, it can not be ruled out that in the case of an unprotected piezoelectric actuator, diesel fuel penetrates into the defects. Since the piezoelectric actuator consists of layers which are separated by positive and negative internal electrodes, it must be ensured that no electrical flashover occurs in the case of any exposed internal electrodes.
  • the invention is based on an arrangement described above with a piezoelectric actuator, which is constructed with a piezoelectric element of a multi-layer structure of piezoelectric layers, wherein between the piezoelectric layers arranged internal electrodes in the direction of the La gene structure of the piezoelectric element alternately applied to a different polarity of an electrical voltage.
  • a space filled with a liquid insulating medium wherein the liquid insulating medium surrounds at least the piezoelectric layers and is sealed off from another liquid medium in an outer space by a form-tolerant sleeve.
  • the sleeve according to the invention advantageously in predetermined limits at least in partial areas of their elongated elastic structure, wherein at the axial ends of the sleeve in the region of an actuator base and an actuator head sealing points are provided with sealing elements corresponding to the elasticity of the sleeve by molding and / or position change a predetermined volume compensation in space with the isolation medium, for example, a capacitor, cause.
  • the sealing element is located in the region of the actuator head in an axially extending annular groove in which the sealing element is axially movable for volume compensation.
  • the inventive arrangement with the piezoelectric actuator may be a piezoinjector for an injection system for fuel in an internal combustion engine, wherein the fuel, for example diesel, flows through the outer space.
  • the inventive sleeve thus allows in a simple manner that the piezoceramic of the piezoelectric actuator can be permanently protected during operation against impurities and water in the diesel fuel and thus electrical flashovers between the internal electrodes can be avoided.
  • the ceramic of the piezoelectric actuator during operation can perform a stroke of several microns.
  • connection to the actuator head and the actuator foot must be fuel-resistant and tight in any case.
  • conventional coating methods it can not be ensured that defects underneath the actuator surface, for example in the area of electrical contacting, are also coated completely free of bubbles.
  • the bubbles could possibly be printed together at 2000 bar pressure, which could lead to mechanical stresses in the coating or even to cracks.
  • the sleeve may also be an elastic hose, which is attached with corresponding sealing points directly on the actuator head and the actuator foot.
  • the sleeve is a solid sleeve made of plastic, for example an injection molded part, which is designed thinner walled in the central region than in the end regions, and that the sleeve with appropriate sealing points len directly on the actuator head and the actuator base attached is.
  • insert parts can be inserted in the sleeve in the region of the sealing points for reinforcement in this area.
  • Figure 1 shows a section through an arrangement with a piezoelectric actuator in a piezo injector for the fuel injection in an internal combustion engine
  • Figure 2 is a detailed view of the piezoelectric injector according to the figure 1 and
  • FIG. 3 shows a further modified exemplary embodiment of the piezo injector according to FIG. 1.
  • FIG. 1 shows a basic structure of an arrangement 1 with a piezoactuator, which can be used, for example, for needle stroke control in the injection system for fuel in an internal combustion engine.
  • a piezoactuator which can be used, for example, for needle stroke control in the injection system for fuel in an internal combustion engine.
  • an injector body 2 through which the electrical supply lines 3 and 4 for the electrical voltage for controlling a piezoelectric element 5 are guided.
  • the piezoelectric element 5 is part of a piezoelectric actuator 6, which also has an actuator foot 7 and an actuator head 8 up.
  • the leads 3 and 4 are led to external electrodes on the piezoelectric element 5, which when actuated by a voltage application via a vertically below the piezoelectric actuator 6 located mechanical arrangement with a coupler 9 on a nozzle needle 10 acts such that a release of a Duseno réelle 11 can take place here.
  • a fuel guided through the interior of the injector body 2 can thus be injected by the actuator module body 12 into the combustion chamber of an internal combustion engine, not shown here.
  • the actuator module body 12 is mechanically fixed and pressure-tightly connected to the injector body 2.
  • FIG. 2 shows an enlarged illustration of the region with the piezoelectric actuator 6 according to FIG. 1, identical reference symbols having been assigned to identical components.
  • the pressure oscillations occurring in the space 13 during operation of the arrangement 1 are thus transmitted directly to the insulating medium in the space 14 via the preferably thin-walled sleeve 15.
  • the volume of the space 14 is designed constructive, it comes to volume changes in the range of several due to the low compressibility of the insulating medium in space 14 at pressures of 2000 bar and a corresponding thermal expansion in the range of - 40 to +150 0 C. mm 3 .
  • the sleeve 15 is made of steel, only small volume changes can on the case of this relatively thin wall of the sleeve 15 be compensated.
  • an annular groove 18 for the sealing element 17 is designed so that an axial displacement (arrow 19) of the sealing element 17 is made possible.
  • the cross section of the annular groove 18 multiplied by the axial displacement of the sealing element 17 then corresponds to the volume which can be compensated in the space 14.
  • the piezoelectric actuator 6 can exert as a stroke longitudinal movements, for example, in the order of up to 0.1 mm.
  • the actuator head 8 will move relative to the sleeve 15 in the region of the sealing element 17. Since the stroke is relatively small in relation to the dimensions of the sealing element 17, the stroke is transmitted as deformation or displacement of the elastomeric material of the sealing element 17.
  • the sealing element 17 thus acts like a membrane, which is advantageous in terms of wear and mixing of the media in the spaces 13 and 14.
  • volume compensation is the use of a correspondingly elastic sleeve 15, for example as a piece of hose which seals on the actuator head 8 and on the actuator foot 7 at both axial ends.
  • a correspondingly elastic sleeve 15 inside the tube (corresponding to the sleeve 15) the isolation medium is located in the space 14 and the rail pressure of the medium in the space 13 is transmitted directly to the isolation medium in the space 14.
  • the correspondingly differently designed sealing points of the hose on the actuator head 8 and the actuator base 7 thereby experience no pressure differences, which thus can cause no leaks, since the longitudinal movement of the piezoelectric actuator 6 is directly absorbed by the elasticity of the hose.
  • FIG. 3 shows a further embodiment of the arrangement according to the invention, in which a fixed sleeve 20 is present in the space 13 as sheathing of the insulating medium. Since such a fixed sleeve 20 also provides mechanical protection of the piezoelectric actuator 6 during transport and during assembly, an injection molded part made of plastic can also be used here as a sleeve 20 in combination with correspondingly adapted sealing elements 21 and 22.
  • the sleeve 20 made of plastic is designed thin-walled as at the axial ends, so that here a volume and pressure compensation over a change in diameter can take place according to the arrows 25.

Landscapes

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

Abstract

Système pourvu d'un piézoactionneur (6) fabriqué à partir d'un piézoélément (5) présentant une structure sous forme de plusieurs couches piézoélectriques. Ledit piézoactionneur (6) est entouré par au moins un espace (14) entourant les couches piézoélectriques et rempli par un milieu d'isolation liquide, qui est étanchéifié par rapport à un milieu liquide se trouvant dans un espace externe (13) par un manchon (15; 20) à forme variable. Le manchon (15; 20) possède une structure élastique dans des limites prédéterminées, tout au moins dans certaines parties de son extension longitudinale. Les extrémités axiales du manchon (15; 20) possèdent, dans la zone d'une base (7) de l'actionneur et d'une tête (8) de l'actionneur, des sites d'étanchéité pourvus d'éléments d'étanchéité (16, 17) qui provoquent, en fonction de l'élasticité du manchon (15; 20), par modification de forme et / ou de position, un équilibrage prédéterminé du volume dans l'espace (14) rempli du milieu d'isolation.
EP07729043A 2006-05-17 2007-05-11 Système pourvu d'un piézoactionneur traversé par des milieux liquides Withdrawn EP2020045A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102006022998A DE102006022998A1 (de) 2006-05-17 2006-05-17 Anordnung mit einem von flüssigen Medien umströmten Piezoaktor
PCT/EP2007/054591 WO2007131964A1 (fr) 2006-05-17 2007-05-11 Système pourvu d'un piézoactionneur traversé par des milieux liquides

Publications (1)

Publication Number Publication Date
EP2020045A1 true EP2020045A1 (fr) 2009-02-04

Family

ID=38293148

Family Applications (1)

Application Number Title Priority Date Filing Date
EP07729043A Withdrawn EP2020045A1 (fr) 2006-05-17 2007-05-11 Système pourvu d'un piézoactionneur traversé par des milieux liquides

Country Status (4)

Country Link
US (1) US20090260598A1 (fr)
EP (1) EP2020045A1 (fr)
DE (1) DE102006022998A1 (fr)
WO (1) WO2007131964A1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100180865A1 (en) * 2006-02-14 2010-07-22 Joachim Vendulet Barrier Coatings for a Piezoelectric Device
JP5195451B2 (ja) * 2008-04-15 2013-05-08 株式会社デンソー 燃料噴射装置、それに用いられる蓄圧式燃料噴射装置システム
CN101807459B (zh) * 2010-03-10 2012-05-23 中国电力科学研究院 一种超高压气体绝缘瓷套管
EP2378107A1 (fr) * 2010-04-19 2011-10-19 Delphi Technologies Holding S.à.r.l. Agencement d'actionneur à utiliser dans un injecteur de carburant

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT369900B (de) * 1981-05-20 1983-02-10 List Hans Messwertaufnehmer mit piezoelektrischem sensorelement
JPS5879116A (ja) * 1981-11-05 1983-05-12 Nissan Motor Co Ltd 内燃機関の燃料噴射量検知装置
JPS60104762A (ja) * 1983-11-10 1985-06-10 Nippon Soken Inc 電歪式アクチュエータ及びそれを用いた燃料噴射弁
DE19909451A1 (de) * 1999-03-04 2000-09-14 Bosch Gmbh Robert Injektor mit einem Piezo-Mehrlagenaktor
DE60104906T2 (de) * 2000-11-13 2005-01-05 Siemens Vdo Automotive Corporation, Auburn Hills Magnetohydraulische ausgleichvorrichtung für kraftstoff-einspritzdüse
JPWO2004015385A1 (ja) * 2002-08-09 2005-12-02 ボッシュ株式会社 圧力センサー、圧力センサーの製造方法および内燃機関の筒内圧検出構造
DE10245109A1 (de) * 2002-09-27 2004-04-08 Siemens Ag Injektor, insbesondere Kraftstoff-Einspritzventil, mit einem piezoelektrischen Aktor
DE10259801A1 (de) * 2002-12-19 2004-07-01 Robert Bosch Gmbh Brennstoffeinspritzventil
ATE375446T1 (de) * 2004-01-13 2007-10-15 Delphi Tech Inc Kraftstoffeinspritzventil
ATE388319T1 (de) * 2004-08-13 2008-03-15 Delphi Tech Inc Einspritzdüse
DE102007018039A1 (de) * 2006-09-14 2008-03-27 Robert Bosch Gmbh Piezoaktormodul mit einem ummantelten Piezoaktor

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2007131964A1 *

Also Published As

Publication number Publication date
DE102006022998A1 (de) 2007-11-22
US20090260598A1 (en) 2009-10-22
WO2007131964A1 (fr) 2007-11-22

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