WO2005076378A1 - Piezo-actionneur pourvu d'une couche d'isolation - Google Patents

Piezo-actionneur pourvu d'une couche d'isolation Download PDF

Info

Publication number
WO2005076378A1
WO2005076378A1 PCT/EP2004/053209 EP2004053209W WO2005076378A1 WO 2005076378 A1 WO2005076378 A1 WO 2005076378A1 EP 2004053209 W EP2004053209 W EP 2004053209W WO 2005076378 A1 WO2005076378 A1 WO 2005076378A1
Authority
WO
WIPO (PCT)
Prior art keywords
sleeve
actuator body
actuator
piezo
sealing material
Prior art date
Application number
PCT/EP2004/053209
Other languages
German (de)
English (en)
Inventor
Friedrich Boecking
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 WO2005076378A1 publication Critical patent/WO2005076378A1/fr

Links

Classifications

    • 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
    • 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
    • F02M63/0014—Valves characterised by the valve actuating means
    • F02M63/0015—Valves characterised by the valve actuating means electrical, e.g. using solenoid
    • F02M63/0026—Valves characterised by the valve actuating means electrical, e.g. using solenoid using piezoelectric or magnetostrictive actuators
    • 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
    • H10N30/50—Piezoelectric or electrostrictive devices having a stacked or multilayer structure

Definitions

  • the invention relates to a piezo actuator, in particular for an injection system of a motor vehicle with an actuator body, made of a piezoelectric material that expands and contracts during operation of the actuator body, at least one inner electrode arranged in the actuator body, at least one outer electrode electrically contacting the inner electrode and an insulating layer surrounding the outer electrode ,
  • the invention further relates to the use of such a piezo actuator in an injection system of a motor vehicle.
  • Piezo actuators of the type mentioned above are used, for example, in internal combustion engines as actuators for common rail fuel injection systems and are arranged there within the injection system in a line or chamber, in which liquid fuel is also under, in some cases, considerable pressure.
  • the piezo actuator works as a so-called “wet actuator", whereby its actuator body, which is made up of several layered piezo elements, is surrounded by the liquid fuel.
  • the liquid fuel which is under high pressure, acts in particular on the side surfaces of the actuator body, on its outer electrodes and also between the piezo elements Due to the pressure, which may be up to 1800 bar, the internal electrodes are heavily loaded and may be pushed into the actuator body, so that the contact between the internal electrodes and the external electrode can be destroyed under certain circumstances.
  • Object and solution of the invention are used, for example, in internal combustion engines as actuators for common rail fuel injection systems and are arranged there within the injection system in a line or chamber, in which liquid fuel is also under, in some cases, considerable pressure.
  • the invention is based on the object of providing a piezo actuator of the type mentioned at the beginning, in which damage to the coupling between the outer electrode and inner electrodes by the fuel, which surrounds the associated actuator body and is under high pressure, is reliably prevented.
  • a piezo actuator according to the preamble of claim 1, in which a sleeve is provided which at least partially directly surrounds the actuator body and the insulating layer. Furthermore, the assignments are through
  • an additional component in the form of a sleeve is provided on a piezo actuator, which is designed and arranged in such a way that it specifically absorbs and discharges the pressure of the fuel that surrounds the actuator body.
  • the insulating layer must first electrically isolate the outer electrodes and seal the actuator body from the surrounding fuel. Furthermore, the insulating layer must transfer heat from the actuator body to the liquid fuel, and finally the insulating layer, as a third function, must also absorb the pressure that is exerted on the actuator body by the surrounding fuel.
  • the function of the power transmission is assigned in particular to a sleeve provided specifically for this purpose, which at least partially directly surrounds the actuator body and the insulating layer.
  • the force directed by the liquid fuel onto the actuator body is intercepted by the sleeve according to the invention without the insulating layer underneath in particular having to absorb this force.
  • the sleeve according to the invention is advantageously provided over the entire height of the actuator body so that, in the case of a cylindrical, in particular cuboid or circular, cylindrical actuator body, the internal electrodes arranged therein are protected overall from the comparatively high pressure of the surrounding fuel.
  • the insulating layer can then be introduced comparatively easily between the actuator body and the sleeve during the manufacture of the piezo actuator 2, for example by a spraying process.
  • a sealing element which seals between the sleeve and the actuator body, is provided on the end regions of the sleeve.
  • a sealing element specifically takes over the function of the fuel seal, so that the sleeve, together with the sealing material, forms a type of capsule on the actuator body, under which the inner electrodes, the outer electrodes and optionally also the insulating layer are then arranged.
  • the sealing material provided according to the invention can also alone form a type of capsule around the actuator body and its inner and outer electrodes by forming the sealing material along the inside of the sleeve, in particular in a layer running between the sleeve and the insulating layer.
  • a solution with an encapsulating sealing material is also advantageous, in which the sealing material extends along the outside of the actuator body, in particular in a layer running between the insulating layer and the actuator body.
  • the sealing material finally extends along the outside of the sleeve, in particular in a layer surrounding the sleeve. Sealing material designed in this way completely takes over the function of the fuel seal, while the sleeve underneath takes over the power transmission and finally the function of heat conduction is assigned to the insulation layer arranged between the sleeve and the actuator body.
  • a clear separation of functions is thus created, so that the individual components of such a piezo actuator can be specifically adapted to the functions assigned to them.
  • Such a simple separation of functions to represent a “wet actuator” is particularly advantageous for “common rail injection systems” on which the fuel surrounding the actuator body is under a comparatively high pressure.
  • FIG. 1 shows a partial longitudinal section of a first exemplary embodiment of a piezo actuator according to the invention
  • FIG. 2 shows a partial longitudinal section of a second exemplary embodiment of a piezo actuator according to the invention
  • 3 shows a partial longitudinal section of a third exemplary embodiment of a piezo actuator according to the invention
  • FIG. 4 shows a partial longitudinal section of a fourth exemplary embodiment of a piezo actuator according to the invention
  • FIG. 5 shows a partial longitudinal section of a fifth exemplary embodiment of a piezo actuator according to the invention.
  • FIG. 1 shows a first exemplary embodiment of a piezo actuator 10 which, as an essential component, comprises a cylindrical actuator body 12 with an actuator head 14 arranged on its end face.
  • the actuator body 12 is constructed from a plurality of layered piezo elements 16, between which there are essentially thin, disk-shaped inner electrodes 18.
  • the inner electrodes are alternately connected to outer electrodes, of which one outer electrode 20 is shown in FIG.
  • the outer electrodes 20 are each in the form of a longitudinal strip on the lateral or side surfaces of the actuator body 20 and serve to make electrical contact with the inner electrodes 18.
  • the outer electrodes 20 and also the jacket or side surfaces of the actuator body 12 are surrounded by an insulation layer 22, which is to perform the following three functions in known piezo actuators:
  • the insulation layer is intended to produce a heat-conducting connection between the actuator body and its surroundings. It is also intended to seal off the actuator body and the internal electrodes therein from this environment and in particular from a liquid fuel located there, and finally the insulation layer should also absorb the force determined by the under Operating conditions high pressure of this liquid fuel is exerted on the actuator body and its internal electrodes.
  • this third function of known insulation layers is transferred to its own additional component, namely to a thin-walled sleeve 24 which directly surrounds the actuator body 12 and the associated insulation layer 22 over the entire height of the actuator body 12.
  • the sleeve 24 thus absorbs that pressure force that is exerted by a liquid fuel surrounding the piezo actuator 10 and under high pressure.
  • the sleeve 24 protects the underlying insulation layer 22 and the outer electrodes 20, the inner electrodes
  • FIG. 2 shows an exemplary embodiment of a piezo actuator 10, in which the function of the fuel seal between the surroundings of the actuator body 12 and its internal electrodes 18 is also taken over by a separate component.
  • This separate component is a sealing material 26 which is injected at the upper end region of the sleeve 24 between this sleeve 24 and the actuator head 14 adjacent there. Under the sealing material 26 there is in a conventional manner the insulation layer 22 which, as in the exemplary embodiment according to FIG. 1, is injected between the sleeve 24 and the actuator body 12.
  • FIGS. 3 to 5 show exemplary embodiments of piezo actuators 10, in which the inner electrodes 18 are completely encapsulated with respect to the surroundings of the actuator body 12 with the aid of the sealing material 26.
  • the sealing material 26 is in turn injected at the end regions of the sleeve 24 between this sleeve 24 and the respectively adjacent actuator head 14.
  • a sealing material layer 28 is also provided, which is based on the sealing material injected on the actuator head 14 26 extends between the insulation layer 22 arranged within the sleeve 24 and the actuator body 12.
  • the sealing material layer 28 extends from that arranged on the actuator head 14
  • the sealing material layer 28 is finally arranged on the outside of the sleeve 24.
  • the sealing material layer 28 according to FIG. 5 extends along the sleeve 24 to the sealing material 26, which is arranged at the end of the sleeve 24 between the actuator head 14 and the sleeve 24 and furthermore which also comprises the end of the sleeve 24 itself.

Landscapes

  • Fuel-Injection Apparatus (AREA)

Abstract

Piézo-actionneur (10) destiné à être utilisé en particulier pour un système d'injection de véhicule à moteur, qui comporte un corps (12) constitué d'une matière piézo-électrique qui se dilate et se contracte lors du fonctionnement dudit corps (12), au moins une électrode interne (18) placée dans le corps (12), au moins une électrode externe (20) se trouvant en contact électrique avec l'électrode interne (18) et une couche d'isolation (22) entourant l'électrode externe (20). Selon la présente invention, ledit piézo-actionneur comporte une douille (24) qui entoure directement au moins partiellement le corps (12) d'actionneur et la couche d'isolation (22).
PCT/EP2004/053209 2004-02-03 2004-12-01 Piezo-actionneur pourvu d'une couche d'isolation WO2005076378A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102004005226.3 2004-02-03
DE102004005226A DE102004005226A1 (de) 2004-02-03 2004-02-03 Piezoaktor mit einer Isolierschicht

Publications (1)

Publication Number Publication Date
WO2005076378A1 true WO2005076378A1 (fr) 2005-08-18

Family

ID=34801481

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2004/053209 WO2005076378A1 (fr) 2004-02-03 2004-12-01 Piezo-actionneur pourvu d'une couche d'isolation

Country Status (2)

Country Link
DE (1) DE102004005226A1 (fr)
WO (1) WO2005076378A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007015457A1 (de) * 2007-03-30 2008-10-02 Siemens Ag Piezoelektrisches Bauteil mit Sicherheitsschicht und Verfahren zu dessen Herstellung

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010061946A1 (de) * 2010-11-25 2012-05-31 Robert Bosch Gmbh Piezoelektrisches Aktormodul und Brennstoffeinspritzventil

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19818068A1 (de) * 1998-04-22 1999-10-28 Siemens Ag Piezoelektronischer Aktor für einen Stellantrieb
DE19860001A1 (de) * 1998-12-23 2000-07-06 Siemens Ag Piezoelektrisches Bauelement, Verfahren zu dessen Herstellung und Verwendung eines derartigen Bauelements
DE10054017A1 (de) * 2000-11-01 2002-05-08 Bosch Gmbh Robert Piezoaktormodul mit Vorrichtung zur Wärmeableitung
US20020084350A1 (en) * 2000-12-28 2002-07-04 Naoyuki Kawazoe Piezoelectric device for injector, method for producing the same, and injector
DE10225408A1 (de) * 2002-06-07 2003-12-24 Epcos Ag Piezoaktor, Verfahren zu dessen Herstellung und dessen Verwendung
DE10231624A1 (de) * 2002-07-12 2004-01-29 Robert Bosch Gmbh Piezoelektrisches Bauelement

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19818068A1 (de) * 1998-04-22 1999-10-28 Siemens Ag Piezoelektronischer Aktor für einen Stellantrieb
DE19860001A1 (de) * 1998-12-23 2000-07-06 Siemens Ag Piezoelektrisches Bauelement, Verfahren zu dessen Herstellung und Verwendung eines derartigen Bauelements
DE10054017A1 (de) * 2000-11-01 2002-05-08 Bosch Gmbh Robert Piezoaktormodul mit Vorrichtung zur Wärmeableitung
US20020084350A1 (en) * 2000-12-28 2002-07-04 Naoyuki Kawazoe Piezoelectric device for injector, method for producing the same, and injector
DE10225408A1 (de) * 2002-06-07 2003-12-24 Epcos Ag Piezoaktor, Verfahren zu dessen Herstellung und dessen Verwendung
DE10231624A1 (de) * 2002-07-12 2004-01-29 Robert Bosch Gmbh Piezoelektrisches Bauelement

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007015457A1 (de) * 2007-03-30 2008-10-02 Siemens Ag Piezoelektrisches Bauteil mit Sicherheitsschicht und Verfahren zu dessen Herstellung
DE102007015457B4 (de) * 2007-03-30 2009-07-09 Siemens Ag Piezoelektrisches Bauteil mit Sicherheitsschicht, Verfahren zu dessen Herstellung und Verwendung
US8492955B2 (en) 2007-03-30 2013-07-23 Siemens Aktiengesellschaft Piezoelectric component comprising security layer and method for the production thereof

Also Published As

Publication number Publication date
DE102004005226A1 (de) 2005-08-18

Similar Documents

Publication Publication Date Title
EP1485607B1 (fr) Element d'etancheite pour l'actionneur piezoelectrique d'une soupape d'injection de carburant
EP1901360B1 (fr) Module de piezoactionneur doté d'un piezoactionneur gainé
EP1906464A1 (fr) Piézoacteur doté d'une gaine, destiné à la saisie dans un piézoinjecteur
EP2080238B1 (fr) Module actionneur doté d'un actionneur piézo-électrique enveloppé
EP3428443B1 (fr) Manchon de pressage pour une culasse
EP1628015B1 (fr) Système d'étanchéité pour actionneur piezoélectrique d'injecteur de carburant
EP2018672B1 (fr) Injecteur muni d'un activateur piézoélectrique pour moteur à combustion interne
DE102006025820A1 (de) Piezoelektrischer Aktor mit einer Ummantelung aus einem Verbundwerkstoff
WO2005076378A1 (fr) Piezo-actionneur pourvu d'une couche d'isolation
WO2006018399A1 (fr) Servo-moteur pour un injecteur de carburant d'un moteur a combustion interne et utilisation de ce servo-moteur
DE102006006076B4 (de) Piezo-Aktor, Verfahren zum Herstellen eines Piezo-Aktors und Einspritzsystem mit einem solchen
EP1909339B1 (fr) Module d'actionneur ayant un piezoactionneur gainé
EP2636081B1 (fr) Unité actionneur et son procédé de production
EP3036431B1 (fr) Actionneur piézo-électrique pour injecteur de carburant et injecteur de carburant
EP1912265B1 (fr) Module d'actionneur doté d'un piézoactionneur gainé
EP2031669B1 (fr) Module d'actionneur piézoélectrique comprenant une enveloppe du piézoactionneur et son procédé de fabrication
EP2013923B1 (fr) Piézo-actionneur comportant un gainage
DE102019103569B4 (de) Leiterrahmen für eine Batterievorrichtung eines Elektrofahrzeugs
EP1936708A2 (fr) Module actionneur doté d'un piézoactionneur gainé et procédé de fabrication de celui-ci
DE102005001005B4 (de) Stellantrieb zur Betätigung eines Kraftstoffeinspritzventils
DE102010055004A1 (de) Piezoelementstapel
EP2071645B1 (fr) Module piézoactionneur doté d'une construction multicouches de piézoactionneurs
EP1768198B1 (fr) Actionneur piézo-électrique
EP2109160A1 (fr) Module piézoactionneur pour un agencement entouré par un milieu fluide
DE102015213003A1 (de) Piezoaktormodul und Piezoinjektor

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase