EP0311608A1 - Spark plug with surface discharge section. - Google Patents

Spark plug with surface discharge section.

Info

Publication number
EP0311608A1
EP0311608A1 EP87903248A EP87903248A EP0311608A1 EP 0311608 A1 EP0311608 A1 EP 0311608A1 EP 87903248 A EP87903248 A EP 87903248A EP 87903248 A EP87903248 A EP 87903248A EP 0311608 A1 EP0311608 A1 EP 0311608A1
Authority
EP
European Patent Office
Prior art keywords
platinum
layer
electrically conductive
spark plug
sliding
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
EP87903248A
Other languages
German (de)
French (fr)
Other versions
EP0311608B1 (en
Inventor
Karl-Hermann Friese
Werner Gruenwald
Kurt Schmid
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.)
OFFERTA DI LICENZA AL PUBBLICO
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 EP0311608A1 publication Critical patent/EP0311608A1/en
Application granted granted Critical
Publication of EP0311608B1 publication Critical patent/EP0311608B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01TSPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T13/00Sparking plugs
    • H01T13/52Sparking plugs characterised by a discharge along a surface

Definitions

  • the invention relates to a spark plug with sliding spark gap according to the preamble of the main claim.
  • a spark plug with a sliding spark gap is known, in which the isolator body is cross-divided and has a connection-side upper part made of a material with a relatively low dielectric constant and a lower part on the combustion chamber side made of a material with a much higher dielectric constant.
  • Such spark plugs are in perfect working order, but are relatively complicated to manufacture due to the divided insulating body.
  • the spark plug according to the invention with the characterizing features of the main claim has the advantage that it is easy to manufacture by thick-film technology and the sliding spark layers are highly effective and long-term stable.
  • the measures listed in the dependent claims are advantageous further developments and improvements in the main claim specified spark plug possible. It is particularly advantageous if the electrically non-conductive ceramic made of Al p Q and the electrically conductive layer on the ceramic made of platinum or a platinum-Al 0 mixture with 60 to 85% by weight? Platinum consists, while the layer of the sliding spark gap consists of a platinum-Al-O, mixture with 1.0 to 40% by weight? Platinum is made.
  • FIG. 1 An embodiment of the invention is shown in the drawing and explained in more detail in the following description.
  • the figure shows an exemplary embodiment in a schematic, sectioned illustration.
  • the spark plug consists of a spark plug body 1 made of aluminum oxide, with a bore 2 in the part on the combustion chamber side, in which there is a T-shaped component which, for example, consists of aluminum oxide and has various surface coatings. With 4 the counter electrode is indicated.
  • the component 3 has a coating 5 inside the spark plug body 1 and inside the bore 2, and also protruding a little further, which is electrically conductive and consists either of platinum or of a platinum / Al O mixture with 60 to 85% by weight platinum and has a thickness of 5 to 15 ⁇ m.
  • the coating 6 on the component 3 in the vicinity of the counter electrode 4, to which this layer 6 makes the electrical contact, is made of the same material.
  • the electrically conductive coating 5 is contacted within the spark plug body 1 by means of an electrically conductive glass 7 in the form of a glass melt flow, as is known, for example, from US Pat. No. 3,909,459.
  • the sliding spark layer 8 between the coatings 5 and 6 consists of a platinum / Al 0 mixture with 10 to 40 wt. Platinum, which has the property after sintering, has no intrinsic conductivity, since individual conductivity islands are formed which, although they have no electrical contact with one another, nevertheless allow high displacement currents, which corresponds to a high dielectric constant.
  • This coating 8 is also applied in a thickness of 5 to 15 ⁇ m.
  • the T-shaped component 3 is first made from aluminum oxide and annealed at 1100 to 1150 ° C., but not yet sintered.
  • the electrically conductive coatings 5 and 6 and thereon are then immersed or printed onto this component 3 then apply the sliding spark layer 8 by printing or brushing on.
  • the component 3 with the coatings 5, 6 and 8 is then introduced from the inside into the bore 2 of the spark plug body 1, which has a diameter of just equal and which is also also only annealed Temperatures between 1500 and 1600 ° C. are sintered in the usual way, whereby a firm fit is created between component 3 and spark plug body 1 and the sliding spark layer 8 obtains the properties described above.
  • the electrically conductive glass 7 in is then inserted into the cavity of the spark plug body 1 Formed a glass melt flow and the upper Te not shown in the figure
  • the central electrode is introduced with the connection, whereupon the whole is melted at a melting temperature suitable for the respective glass type, which can be in the range between 800 and 900 ° C.
  • the whole is flared in a gas-tight manner in the spark plug housing, not shown, with the ground electrode 4 formed thereon, in such a way that the electrically conductive coating 6 and the counter electrode 4 touch.
  • Practical tests have shown that such spark plugs have a very long service life and the sliding spark layers are highly effective and long-term stable.

Abstract

Bougie d'allumage destinée à être utilisée dans un moteur à combustion interne, et comportant un corps isolant pourvu, dans sa partie terminale côté chambre de combustion, d'une électrode centrale reliée à une masse électroconductrice située à l'intérieur du corps isolant, ainsi qu'une contre-électrode et une section d'étincelle glissante entre l'électrode centrale et la contre-électrode. Les électrodes centrales et la section d'étincelle glissante sont constituées d'un élément céramique en une seule pièce électriquement non conducteur portant en surface, dans la région du corps isolant et de la contre-électrode, une couche électroconductrices, et dans la région de la section d'étincelle glissante, une couche qui, après vitrification, ne présente aucune conductivité intrinsèque et permet le passage de courants de déplacements élevés. L'élément céramique électriquement non conducteur se compose de préférence de Al2O3, la couche électroconductrice sur l'élément céramique se compose de platine ou d'un mélange de platine/Al2O3 avec au moins 60 % en poids de platine, et la couche de la section d'étincelle glissante se compose d'un mélange de platine/Al2O3 avec un maximum de 40 % en poids de platine.Spark plug intended for use in an internal combustion engine, and comprising an insulating body provided, in its end part on the combustion chamber side, with a central electrode connected to an electrically conductive ground located inside the insulating body, as well as a counter electrode and a sliding spark section between the central electrode and the counter electrode. The central electrodes and the sliding spark section are made of an electrically non-conductive one-piece ceramic element carrying on the surface, in the region of the insulating body and the counter electrode, an electrically conductive layer, and in the region of the sliding spark section, a layer which, after vitrification, has no intrinsic conductivity and allows the passage of high displacement currents. The electrically non-conductive ceramic element is preferably composed of Al2O3, the electrically conductive layer on the ceramic element consists of platinum or a mixture of platinum / Al2O3 with at least 60% by weight of platinum, and the layer of the Sliding spark section consists of a mixture of platinum / Al2O3 with a maximum of 40% by weight platinum.

Description

Zündkerze mit GleitfunkenstreckeSpark plug with sliding spark gap
Stand der TechnikState of the art
Die Erfindung geht aus von einer Zündkerze mit Gleitfunkenstrecke nach der Gattung des Hauptanspruchs. Aus der DE-OS 35 33 123 ist beispielsweise eine Zündkerze mit Gleitfunkenstrecke bekannt, bei der der Isolatorkδrper quergeteilt ist und ein anschlußseitiges Oberteil aus einem Werkstoff mit relativ niedriger Dielektrizitäts¬ konstante und ein brennraumseitiges Unterteil aus einem Werkstoff mit einer sehr viel höheren Dielektrizitätskonstanten aufweist. Derartige Zündkerzen sind zwar in der Funktion einwandfrei, sind aber in der Herstellung verhältnismäßig kompliziert durch den geteilten Isolierkörper.The invention relates to a spark plug with sliding spark gap according to the preamble of the main claim. From DE-OS 35 33 123, for example, a spark plug with a sliding spark gap is known, in which the isolator body is cross-divided and has a connection-side upper part made of a material with a relatively low dielectric constant and a lower part on the combustion chamber side made of a material with a much higher dielectric constant. Such spark plugs are in perfect working order, but are relatively complicated to manufacture due to the divided insulating body.
Vorteile der ErfindungAdvantages of the invention
Die erfindungsgemäße Zündkerze mit den kennzeichnenden Merkmalen des Hauptanspruchs hat demgegenüber den Vorteil, daß sie durch Dick¬ schichttechnik einfach herzustellen ist und die Gleitfunkenschichten hochwirksam und langzeitstabil sind.In contrast, the spark plug according to the invention with the characterizing features of the main claim has the advantage that it is easy to manufacture by thick-film technology and the sliding spark layers are highly effective and long-term stable.
Durch die in den Unteransprüchen aufgeführten Maßnahmen sind vor¬ teilhafte Weiterbildungen und Verbesserungen der im Hauptanspruch angegebenen Zündkerze möglich. Besonders vorteilhaft ist es, wenn die elektrisch nicht leitende Keramik aus AlpQ, und die elek¬ trisch leitende Schicht auf der Keramik aus Platin oder einem Platin-AI 0 -Gemisch mit 60 bis 85 Gew.-? Platin besteht, wäh¬ rend die Schicht der Gleitfunkenstrecke aus einem Platin-Al-O,- Gemisch mit 1.0 bis 40 Gew.-? Platin hergestellt wird.The measures listed in the dependent claims are advantageous further developments and improvements in the main claim specified spark plug possible. It is particularly advantageous if the electrically non-conductive ceramic made of Al p Q and the electrically conductive layer on the ceramic made of platinum or a platinum-Al 0 mixture with 60 to 85% by weight? Platinum consists, while the layer of the sliding spark gap consists of a platinum-Al-O, mixture with 1.0 to 40% by weight? Platinum is made.
Zeichnungdrawing
Ein Ausführungsbeispiel der Erfindug ist in der Zeichnung darge¬ stellt und in der nachfolgenden Beschreibung näher erläutert. Die Figur zeigt ein Ausführungsbeispiel in einer schematischen, ge¬ schnittenen Darstellung.An embodiment of the invention is shown in the drawing and explained in more detail in the following description. The figure shows an exemplary embodiment in a schematic, sectioned illustration.
Beschreibung des AusführungsbeispielsDescription of the embodiment
Die Zündkerze nach der Figur besteht aus einem Zündkerzenkörper 1 aus Aluminiumoxid, mit einer Bohrung 2 im brennraumseitigen Teil, in welcher sich ein T-fδrmiges Bauteil befindet, das beispielsweise aus Aluminiumoxid besteht und verschiedene Oberflächenbeschichtungen trägt. Mit 4 ist die Gegenelektrode angedeutet. Das Bauteil 3 trägt innerhalb des Zündkerzenkörpers 1 und innerhalb der Bohrung 2 sowie auch noch ein wenig darüber hinausragend eine Beschichtung 5, die elektrisch leitfähig ist und entweder aus Platin oder aus einem Platin/Al O -Gemisch mit 60 bis 85 Gew.-% Platin besteht und eine Dicke von 5 bis 15 ,um aufweist. Aus dem gleichen Material besteht die Beschichtung 6 auf dem Bauteil 3 in Nachbarschaft der Gegenelektrode 4, zu welcher diese Schicht 6 den elektrischen Kontakt herstellt. Die Kontaktierung der elektrisch leitfähigen Beschichtung 5 innerhalb des Zündkerzenkδrpers 1 erfolgt durch ein elektrisch leitfähiges Glas 7 in Form eines Glasschmelzflusses, wie er beispielsweise aus der US-PS 3 909 459 bekannt ist. Die Gleitfunkenschicht 8 zwischen den Beschichtungen 5 und 6 besteht aus einem Platin/AI 0 -Gemisch mit 10 bis 40 Gew.-? Platin, das nach dem Sintern die Eigenschaft hat, keine Eigenleitfähigkeit auf¬ zuweisen, da sich einzelne Leitfähigkeitsinseln bilden, die zwar keinen elektrischen Kontakt miteinander haben, jedoch hohe Ver¬ schiebungsströme ermöglichen, was einer hohen Dielektrizitäts¬ konstanten entspricht. Diese Beschichtung 8 wird ebenfalls in einer Dicke von 5 bis 15 ,um aufgebracht.The spark plug according to the figure consists of a spark plug body 1 made of aluminum oxide, with a bore 2 in the part on the combustion chamber side, in which there is a T-shaped component which, for example, consists of aluminum oxide and has various surface coatings. With 4 the counter electrode is indicated. The component 3 has a coating 5 inside the spark plug body 1 and inside the bore 2, and also protruding a little further, which is electrically conductive and consists either of platinum or of a platinum / Al O mixture with 60 to 85% by weight platinum and has a thickness of 5 to 15 µm. The coating 6 on the component 3 in the vicinity of the counter electrode 4, to which this layer 6 makes the electrical contact, is made of the same material. The electrically conductive coating 5 is contacted within the spark plug body 1 by means of an electrically conductive glass 7 in the form of a glass melt flow, as is known, for example, from US Pat. No. 3,909,459. The sliding spark layer 8 between the coatings 5 and 6 consists of a platinum / Al 0 mixture with 10 to 40 wt. Platinum, which has the property after sintering, has no intrinsic conductivity, since individual conductivity islands are formed which, although they have no electrical contact with one another, nevertheless allow high displacement currents, which corresponds to a high dielectric constant. This coating 8 is also applied in a thickness of 5 to 15 μm.
Zur Herstellung dieser Zündkerze wird zunächst das T-förmige Bauteil 3 aus Aluminiumoxid hergestellt und bei 1100 bis 1150" °C 'verglüht, aber noch nicht gesintert. Auf dieses Bauteil 3 werden dann durch Tauchen oder Aufdrucken die elektrisch leitfähigen Beschichtungen 5 und 6 und daran anschließend durch Aufdrucken oder Aufpinseln die Gleitfunkenschicht 8 aufgebracht. Danach wird das Bauteil 3 mit den Beschichtungen 5, 6 und 8 in die im Durchmesser gerade passende Bohrung 2 des Zündkerzenkδrpers 1, der ebenfalls nur verglüht ist, von innen eingebracht. Das Ganze wird dann bei Temperaturen zwischen 1500 und 1600 °C in der üblichen Weise gesintert, wobei zwischen Bauteil 3 und Zündkerzenkörper 1 ein fester Sitz entsteht und die Gleitfunkenschicht 8 die obenbeschriebenen Eigenschaften erhält. In den Hohlraum des Zündkerzenkörpers 1 wird dann das -elektrisch leit¬ fähige Glas 7 in Form eines Glasschmelzflusses eingefüllt und der in der Figur nicht dargestellte obere Teil der Mittelelektrode mit dem Anschluß eingebracht, worauf das Ganze bei einer für die jeweilige Glassorte geeigneten Einschmelztemperatur, die im Bereich zwischen 800 und 900 °C liegen kann, eingeschmolzen wird. Nach dem Abkühlen wird das Ganze in das nicht dargestellte Zündkerzengehäuse mit der daran angeformten Masseelektrode 4 derart gasdicht eingebördelt, daß die elektrisch leitfähige Beschichtung 6 und die Gegenelektrode 4 sich berühren. Praktische Versuche haben ergeben, daß derartige Zündkerzen sehr gute Standzeiten haben und die Gleitfunkenschichten hochwirksam und langzeitstabil sind. To produce this spark plug, the T-shaped component 3 is first made from aluminum oxide and annealed at 1100 to 1150 ° C., but not yet sintered. The electrically conductive coatings 5 and 6 and thereon are then immersed or printed onto this component 3 then apply the sliding spark layer 8 by printing or brushing on. The component 3 with the coatings 5, 6 and 8 is then introduced from the inside into the bore 2 of the spark plug body 1, which has a diameter of just equal and which is also also only annealed Temperatures between 1500 and 1600 ° C. are sintered in the usual way, whereby a firm fit is created between component 3 and spark plug body 1 and the sliding spark layer 8 obtains the properties described above. The electrically conductive glass 7 in is then inserted into the cavity of the spark plug body 1 Formed a glass melt flow and the upper Te not shown in the figure The central electrode is introduced with the connection, whereupon the whole is melted at a melting temperature suitable for the respective glass type, which can be in the range between 800 and 900 ° C. After cooling, the whole is flared in a gas-tight manner in the spark plug housing, not shown, with the ground electrode 4 formed thereon, in such a way that the electrically conductive coating 6 and the counter electrode 4 touch. Practical tests have shown that such spark plugs have a very long service life and the sliding spark layers are highly effective and long-term stable.

Claims

Ansprüche Expectations
1. Zündkerze mit Gleitfunkenstrecke, für Brennkraftmaschinen, mit einem Isolierkörper, der in seinem brennraumseitigen Endabschnitt eine Mittelelektrode auf eist,• die mit einer im Innern des Isolier¬ körpers vorhandenen elektrisch leitfähigen Masse in Verbindung- steht, und mit einer Gβgenelektrode sowie einer Gleitfunkenstreckβ zwischen der Mittelelektrode und der Gegenelektrode, dadurch gekennzeichnet, daß Mittelelektrode und Gleitfunkenstrecke aus einer elektrisch nicht leitenden, einstückigen Keramik bestehen, die auf ihrer Ober¬ fläche im Bereich des Isolierkörpers und der Gegenelektrode eine elektrisch leitende Schicht und im Bereich der Gleitfunkenstrecke eine nach dem Sintern keine Eigenleitfähigkeit aufweisende Schicht, die hohe Verschiebungsstrδme ermöglicht, tragen.1. Spark plug with sliding spark gap, for internal combustion engines, with an insulating body which has a central electrode in its end section on the combustion chamber, • which is connected to an electrically conductive mass present in the inside of the insulating body, and with a casting electrode and a sliding spark gap between the center electrode and the counter electrode, characterized in that the center electrode and sliding spark gap consist of an electrically non-conductive, one-piece ceramic which has an electrically conductive layer on its surface in the area of the insulating body and the counter electrode and none after sintering in the area of the sliding spark gap Layer with intrinsic conductivity, which enables high displacement currents.
2. Zündkerze nach Anspruch 1, dadurch gekennzeichnet, daß die elektrisch nicht leitende Keramik aus Al-O-, die elektrisch leitende Schicht auf der Keramik aus Platin oder einem Platin/Al D,-Gemisch mit mindestens 60 Gew.-? Pt und die Schicht der Gleitfunkenstrecke aus einem Platin/Al20_-Gemisch mit maximal 40 Gew.-? Pt besteht.2. Spark plug according to claim 1, characterized in that the electrically non-conductive ceramic made of Al-O-, the electrically conductive layer on the ceramic made of platinum or a platinum / Al D, mixture with at least 60% by weight? Pt and the layer of the sliding spark gap made of a platinum / Al 2 0_ mixture with a maximum of 40% by weight? Pt exists.
3- Zündkerze nach Anspruch 2, dadurch gekennzeichnet, daß die elektrisch leitende Schicht auf der Keramik aus Platin oder einem Platin/AI 0 -Gemisch mit 60 bis 85 Gew.-? Pt und die Schicht der Gleitfunkenstrecke aus einem Platin/A1?Q,-Gemisch mit 10 bis 40 Gew.-? Pt besteht. 3- spark plug according to claim 2, characterized in that the electrically conductive layer on the ceramic of platinum or a platinum / Al 0 mixture with 60 to 85 wt .-? Pt and the layer of the sliding spark gap from a platinum / A1 ? Q, mixture of 10 to 40% by weight? Pt exists.
EP19870903248 1986-06-12 1987-05-23 Spark plug with surface discharge section Expired - Lifetime EP0311608B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3619854 1986-06-12
DE19863619854 DE3619854A1 (en) 1986-06-12 1986-06-12 SPARK PLUG WITH GLIDING RANGE

Publications (2)

Publication Number Publication Date
EP0311608A1 true EP0311608A1 (en) 1989-04-19
EP0311608B1 EP0311608B1 (en) 1991-10-16

Family

ID=6302904

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19870903248 Expired - Lifetime EP0311608B1 (en) 1986-06-12 1987-05-23 Spark plug with surface discharge section

Country Status (5)

Country Link
US (1) US4939409A (en)
EP (1) EP0311608B1 (en)
JP (1) JPH01502945A (en)
DE (2) DE3619854A1 (en)
WO (1) WO1987007778A1 (en)

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4089012B2 (en) * 1997-09-24 2008-05-21 株式会社デンソー Spark plug
US6078130A (en) * 1997-11-10 2000-06-20 Altronic, Inc. Spark plug with specific construction to avoid unwanted surface discharge
AU1494599A (en) * 1997-12-17 1999-07-05 Dawson Royalties Limited Spark plug
US7224108B2 (en) * 2001-02-15 2007-05-29 Integral Technologies, Inc. Low cost spark plug manufactured from conductive loaded resin-based materials
DE502004003751D1 (en) * 2004-01-05 2007-06-21 Ford Global Tech Llc spark plug
US20070188064A1 (en) * 2006-02-13 2007-08-16 Federal-Mogul World Wide, Inc. Metallic insulator coating for high capacity spark plug
US8278808B2 (en) * 2006-02-13 2012-10-02 Federal-Mogul Worldwide, Inc. Metallic insulator coating for high capacity spark plug
JP2013535786A (en) 2010-07-29 2013-09-12 フェデラル−モーグル・イグニション・カンパニー Electrode material for use with spark plugs
EP2659557B2 (en) 2010-12-29 2019-01-16 Federal-Mogul Ignition Company Corona igniter having improved gap control
US8471451B2 (en) 2011-01-05 2013-06-25 Federal-Mogul Ignition Company Ruthenium-based electrode material for a spark plug
WO2012102994A2 (en) 2011-01-27 2012-08-02 Federal-Mogul Ignition Company Electrode material for a spark plug
DE112012000947B4 (en) 2011-02-22 2018-03-22 Federal-Mogul Ignition Company Method for producing an electrode material for a spark plug
DE112012002699B4 (en) 2011-06-28 2018-12-13 Federal-Mogul Ignition Company Spark plug and method of manufacturing an electrode of a spark plug
US10044172B2 (en) 2012-04-27 2018-08-07 Federal-Mogul Ignition Company Electrode for spark plug comprising ruthenium-based material
US8890399B2 (en) 2012-05-22 2014-11-18 Federal-Mogul Ignition Company Method of making ruthenium-based material for spark plug electrode
US8979606B2 (en) 2012-06-26 2015-03-17 Federal-Mogul Ignition Company Method of manufacturing a ruthenium-based spark plug electrode material into a desired form and a ruthenium-based material for use in a spark plug
JP7022628B2 (en) 2017-03-31 2022-02-18 株式会社Soken Spark plug for internal combustion engine
JP7194550B2 (en) 2018-10-03 2022-12-22 株式会社Soken Spark plug for internal combustion engine

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB645403A (en) * 1939-02-14 1950-11-01 Wijtze Beije Smits Improvements in or relating to sparking plugs
FR886454A (en) * 1942-06-01 1943-10-15 New spark plug
GB719628A (en) * 1951-10-09 1954-12-08 Plessey Co Ltd Improvements in or relating to sparking plug assemblies
DE2050330A1 (en) * 1970-10-14 1972-04-20 Daimler Benz Ag Sliding spark plug
JPS5642981A (en) * 1979-09-14 1981-04-21 Ngk Spark Plug Co Inignition plug and production thereof
ZA805008B (en) * 1979-10-22 1981-08-26 Champion Spark Plug Co Spark igniter
DE3038720A1 (en) * 1980-10-14 1982-06-03 Robert Bosch Gmbh, 7000 Stuttgart SPARK PLUG FOR INTERNAL COMBUSTION ENGINE

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8707778A1 *

Also Published As

Publication number Publication date
US4939409A (en) 1990-07-03
DE3773936D1 (en) 1991-11-21
WO1987007778A1 (en) 1987-12-17
DE3619854A1 (en) 1987-12-17
JPH01502945A (en) 1989-10-05
EP0311608B1 (en) 1991-10-16

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