WO1989005564A1 - X-ray diagnostic apparatus - Google Patents

X-ray diagnostic apparatus Download PDF

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Publication number
WO1989005564A1
WO1989005564A1 PCT/FR1988/000595 FR8800595W WO8905564A1 WO 1989005564 A1 WO1989005564 A1 WO 1989005564A1 FR 8800595 W FR8800595 W FR 8800595W WO 8905564 A1 WO8905564 A1 WO 8905564A1
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WO
WIPO (PCT)
Prior art keywords
heating
high voltage
diagnostic apparatus
ray
ray tube
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.)
Ceased
Application number
PCT/FR1988/000595
Other languages
French (fr)
Inventor
Hans Aldenhövel
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.)
General Electric CGR SA
Original Assignee
General Electric CGR SA
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 General Electric CGR SA filed Critical General Electric CGR SA
Publication of WO1989005564A1 publication Critical patent/WO1989005564A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05GX-RAY TECHNIQUE
    • H05G1/00X-ray apparatus involving X-ray tubes; Circuits therefor
    • H05G1/08Electrical details
    • H05G1/26Measuring, controlling or protecting
    • H05G1/30Controlling
    • H05G1/52Target size or shape; Direction of electron beam, e.g. in tubes with one anode and more than one cathode
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05GX-RAY TECHNIQUE
    • H05G1/00X-ray apparatus involving X-ray tubes; Circuits therefor
    • H05G1/08Electrical details
    • H05G1/26Measuring, controlling or protecting
    • H05G1/30Controlling
    • H05G1/34Anode current, heater current or heater voltage of X-ray tube
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05GX-RAY TECHNIQUE
    • H05G1/00X-ray apparatus involving X-ray tubes; Circuits therefor
    • H05G1/08Electrical details
    • H05G1/70Circuit arrangements for X-ray tubes with more than one anode; Circuit arrangements for apparatus comprising more than one X ray tube or more than one cathode

Definitions

  • X-ray tubes are provided with several focal points.
  • the sizes of the hearths are different. In this respect, it does not matter whether the fireplaces are located one behind the other or superimposed.
  • the heating transformer also called the heating converter, is subjected to its cathode at high voltage potential.
  • the output of the high voltage generator is equipped with circuit breakers in order to supply high voltage each time. the corresponding X-ray tube.
  • the heating transformer and also the high voltage are switched on immediately before the start of shooting by the X-ray tube.
  • Heating transformers are relatively expensive with regard to insulation since the secondary winding must have insulation for 75 V relative to the earth potential. That is also the reason why, when connecting several X-ray tubes, two heating converters must always be incorporated in a high voltage transformer. With expensive circuit breakers placed on the high voltage side, three-pole switching is carried out both for high voltage and for heating. Switching the heating of the tubes is, however, very problematic since high heating currents have to be controlled in insulating oil. Already very small transition resistances to the contacts cause large variations in emission in the X-ray tube. Variations in emission are however not admissible for radiological diagnosis. With the high frequency inverter technique used today, however, it has become possible to manufacture small, inexpensive heating converters.
  • the heating converters thus arranged can also be arranged in series one below the other because they are protected on all sides by wrapping securely against high voltage discharges, so that there is no need to maintain large minimum spacings.
  • the invention relates to a radio diagnostic apparatus for producing radiograms, comprising at least one x-ray tube supplied with high voltage, which can contain several heating wires which are activated by heating converters and whose current values rest heating are adjustable.
  • the object of the invention is to produce a radio diagnostic apparatus for several X-ray tubes, in which the heating voltage of the heating converter is not switched, but only the high voltage for the X-ray tube.
  • the apparatus produced in accordance with the invention is characterized in that, for each X-ray tube connected, there is provided in correspondence with the heating wires installed one or more heating converters in the high voltage generator, and the heating currents are always applied directly to the heating wires of the x-ray tubes and constantly preheat the x-ray tubes in the quiescent condition, and in that only the high voltage for x-ray tube is controlled in correspondence with the required tube.
  • the invention will be explained in more detail below using a schematic file which represents a possible embodiment.
  • Figure 1 shows the high-voltage circuit of an X-ray machine with two bifocals X-ray tubes, the heating wires of which are each connected directly to a separate heating converter.
  • the heating wires (7,8) and (9,10) of the X-ray tubes (11) and (12) are each connected, in the embodiment, with a set of heating converters (5) and (6 ).
  • the set of heating converters comprising as many heating converters as the tube used comprise homes.
  • the sets of heating converters (5) and (6) each comprise two complete heating converters.
  • the invention represents a technically very valid solution since there is no need to switch the high heating currents. Contact fouling can no longer occur, which would result in a variation in the emission of the X-ray tube.
  • Another advantage compared to the prior art consists, with the contactless solution, in eliminating the mechanical part of the heating current generator circuit.
  • the high voltage for X-rays is produced in the high voltage generator (1) and is applied, via the conductors (3) and (4), to the high voltage circuit breaker (2) , the high-voltage circuit breaker (2) applies the high voltage in correspondence to the selected X-ray tube, in this case to the tube

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  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • X-Ray Techniques (AREA)

Abstract

An X-ray diagnostic apparatus is connected to several X-ray tubes (11, 12) provided with heating wires (7, 8, 9, 10). Each heating wire is connected to a separate heat converter (5, 6). The X-ray tubes are thereby preheated in the inoperative state until emission begins. Only the high voltage (1) of the X-ray tubes is switched.

Description

APPAREIL DE RADIO-DIAGNOSTIC RADIO-DIAGNOSTIC APPARATUS

De plus en plus à l'heure actuelle, des tubes à rayons X sont pourvus de plusieurs foyers. Les grosseurs des foyers sont différentes. A cet égard, il est sans importance que les foyers soient situés l'un derrière 1'autre ou superposés.More and more today, X-ray tubes are provided with several focal points. The sizes of the hearths are different. In this respect, it does not matter whether the fireplaces are located one behind the other or superimposed.

Chaque foyer est équipé d'un transformateur de chauffage séparé, car la commutation au potentiel de la haute tension par voie mécanique est trop coûteuse. Le transformateur de chauffage, également appelé convertisseur de chauffage, est soumis à sa cathode au potentiel de haute tension.Each household is equipped with a separate heating transformer, because switching to high voltage potential mechanically is too expensive. The heating transformer, also called the heating converter, is subjected to its cathode at high voltage potential.

Pour des raisons de rentabilité, à l'heure actuelle on relie au générateur de haute tension sélectivement plusieurs tubes à rayons X. Dans ce cas, la sortie du générateur de haute tension est équipée de disjoncteurs afin d'alimenter en haute tension à chaque fois le tube à rayons X correspondant. A cet effet, lors de la sélection du poste de travail correspondant à partir du pupitre de commande, le transformateur de chauffage et également la haute tension sont enclenchés immédiatement avant le début de la prise de vue par le tube à rayons X.For reasons of profitability, at the present time several X-ray tubes are selectively connected to the high voltage generator. In this case, the output of the high voltage generator is equipped with circuit breakers in order to supply high voltage each time. the corresponding X-ray tube. For this purpose, when selecting the corresponding work station from the control console, the heating transformer and also the high voltage are switched on immediately before the start of shooting by the X-ray tube.

Dans la revue Siemens N° 43 (1969) , Cahier 1, il est signalé à la page 28 la possibilité d'utiliser deux transformateurs de chauffage pour un tube à double foyer.In the review Siemens N ° 43 (1969), Book 1, it is indicated on page 28 the possibility of using two heating transformers for a bifocals tube.

Les transformateurs de chauffage sont relativement coûteux en ce qui concerne 1'isolation car l'enroulement secondaire doit avoir une isolation pour 75 V par rapport au potentiel de terre. Cela est également la raison pour laquelle, lors de la liaison de plusieurs tubes à rayons X, on doit toujours incorporer deux convertisseurs de chauffage dans un transformateur haute tension. Avec des disjoncteurs coûteux placés du coté haute tension, on effectue la commutation tripolaire aussi bien de la haute tension que du chauffage. La commutation du chauffage des tubes est cependant très problématique car il faut commander des forts courants de chauffage dans de 1'huile isolante. Déjà de très petites résistances de transition aux contacts provoquent de fortes variations d'émission dans le tube à rayons X. Des variations d'émission ne sont cependant pas admissibles pour le diagnostic radiologique. Avec la technique des onduleurs haute fréquence utilisée à l'heure actuelle, il est cependant devenu possible de fabriquer de petits convertisseurs de chauffage peu coûteux. Egalement le problème de 1-isolation nécessaire a pu être atténué grâce à des moyens d'isolation appropriés. Les convertisseurs de chauffage ainsi agencés peuvent être en outre disposés en série l'un en dessous de l'autre car ils sont protégés de tous côtés par enveloppement de façon sûre contre des décharges de haute tension, de sorte qu'on a pas à maintenir de grands espacements minimaux.Heating transformers are relatively expensive with regard to insulation since the secondary winding must have insulation for 75 V relative to the earth potential. That is also the reason why, when connecting several X-ray tubes, two heating converters must always be incorporated in a high voltage transformer. With expensive circuit breakers placed on the high voltage side, three-pole switching is carried out both for high voltage and for heating. Switching the heating of the tubes is, however, very problematic since high heating currents have to be controlled in insulating oil. Already very small transition resistances to the contacts cause large variations in emission in the X-ray tube. Variations in emission are however not admissible for radiological diagnosis. With the high frequency inverter technique used today, however, it has become possible to manufacture small, inexpensive heating converters. Also the problem of 1-insulation required could be mitigated by means of appropriate insulation. The heating converters thus arranged can also be arranged in series one below the other because they are protected on all sides by wrapping securely against high voltage discharges, so that there is no need to maintain large minimum spacings.

L'invention concerne un appareil de de radio-diagnostic pour la réalisation de radiogrammes, comportant au moins un tube à rayons X alimenté en haute tension, qui peut contenir plusieurs fils chauffants qui sont activés par des convertisseurs de chauffage et dont les valeurs de courant de chauffage de repos sont réglables.The invention relates to a radio diagnostic apparatus for producing radiograms, comprising at least one x-ray tube supplied with high voltage, which can contain several heating wires which are activated by heating converters and whose current values rest heating are adjustable.

L'objet de l'invention est de réaliser un appareil de radio-diagnostic pour plusieurs tubes à rayons X, dans lequel la tension de chauffage du convertisseur de chauffage ne soit pas commutée, mais seulement la haute tension pour le tube à rayons X.The object of the invention is to produce a radio diagnostic apparatus for several X-ray tubes, in which the heating voltage of the heating converter is not switched, but only the high voltage for the X-ray tube.

L'appareil réalisé conformément à l'invention est caractérisé en ce que, pour chaque tube à rayons X raccordé, il est prévu en correspondance aux fils chauffants installés un ou plusieurs convertisseurs de chauffage dans le générateur de haute tension, et les courants de chauffage sont toujours appliqués directement aux fils chauffants des tubes à rayons X et préchauffent constamment les tubes à rayons X dans la condition de repos, et en ce que seulement la haute tension pour tube à rayons X est commandée en correspondance au tube requis. L'invention va être expliquée plus en détail dans la suite à l'aide d'un dossier schématique qui représente un exemple de réalisation possible.The apparatus produced in accordance with the invention is characterized in that, for each X-ray tube connected, there is provided in correspondence with the heating wires installed one or more heating converters in the high voltage generator, and the heating currents are always applied directly to the heating wires of the x-ray tubes and constantly preheat the x-ray tubes in the quiescent condition, and in that only the high voltage for x-ray tube is controlled in correspondence with the required tube. The invention will be explained in more detail below using a schematic file which represents a possible embodiment.

La Figure 1 représente le circuit haute tension d'un appareil à rayons X comportant deux tubes à rayons X à double foyer, dont les fils chauffants sont chacun reliés directement à un convertisseur de chauffage séparé.Figure 1 shows the high-voltage circuit of an X-ray machine with two bifocals X-ray tubes, the heating wires of which are each connected directly to a separate heating converter.

Les fils chauffants (7,8) et (9,10) des tubes à rayons X (11) et (12) sont chacun reliés, dans l'exemple de réalisation, avec un ensemble de convertisseurs de chauffage (5) et (6). L'ensemble de convertisseurs de chauffage comportant autant de convertisseurs de chauffage que le tube utilisé comportent de foyers. Dans l'exemple considéré, les ensembles de convertisseurs de chauffage (5) et (6) comportent chacun deux convertisseurs de chauffage complets.The heating wires (7,8) and (9,10) of the X-ray tubes (11) and (12) are each connected, in the embodiment, with a set of heating converters (5) and (6 ). The set of heating converters comprising as many heating converters as the tube used comprise homes. In the example considered, the sets of heating converters (5) and (6) each comprise two complete heating converters.

Comme mode opératoire, particulièrement avantageux et rationnel, il s'est avéré efficace, pendant les périodes de pause où la haute tension n'est pas appliquée à l'anode, de soumettre les fils chauffants à ce qu'on appelle un chauffage de base. Cela signifie que les fils chauffants de tous les tubes à rayons X raccordés seront préchauffés jusqu'un peu avant l'instant d'enclenchement de l'émission d'électrons. Ce mode opératoire offre aux utilisateurs de gros avantages car tous les postes de travail sont prêts à fonctionner immédiatement. Avec ce type de commande, on élimine les longs temps de retard lors de la réalisation des prises de vues, notamment lors de 1' ngiographie dans deux plans lorsqu'on passe du premier au second plan. Ce mode opératoire a aussi un effet très positif sur la durée de service des tubes à rayons X raccordés et en outre il s'est avéré très avantageux lors de son application à des installations avec pupitres satellites.As a particularly advantageous and rational operating method, it has proved effective during break periods when high voltage is not applied to the anode, subjecting the heating wires to what is called basic heating. This means that the heating wires of all connected X-ray tubes will be preheated until shortly before the start of electron emission. This operating mode offers users great advantages because all workstations are ready to operate immediately. With this type of control, long delay times are eliminated when taking pictures, in particular when scanning in two planes when going from the first to the second plan. This procedure also has a very positive effect on the service life of the connected X-ray tubes and has also proven to be very advantageous when applied to installations with satellite consoles.

L'invention représente une solution techniquement très valable car on n'a pas à commuter les forts courants de chauffage. Il ne peut plus se produire d'encrassements des contacts qui auraient pour conséquence une variation de l'émission du tube à rayons X. Un autre avantage par apport à 1'art antérieur consiste, avec la solution sans contacts, en une suppression de la partie mécanique du circuit générateur des courants de chauffage.The invention represents a technically very valid solution since there is no need to switch the high heating currents. Contact fouling can no longer occur, which would result in a variation in the emission of the X-ray tube. Another advantage compared to the prior art consists, with the contactless solution, in eliminating the mechanical part of the heating current generator circuit.

Dan le principe de circuit représenté, la haute tension pour rayons X est produite dans le générateur de haute tension (1) et est appliquée, par l'intermédiaire des conducteurs (3) et (4), au disjoncteur de haute tension (2) , le disjoncteur haute tension (2) applique en correspondance la haute tension au tube à rayons X sélectionné, dans ce cas au tubeIn the circuit principle shown, the high voltage for X-rays is produced in the high voltage generator (1) and is applied, via the conductors (3) and (4), to the high voltage circuit breaker (2) , the high-voltage circuit breaker (2) applies the high voltage in correspondence to the selected X-ray tube, in this case to the tube

(11) ou (12) et au foyer désiré. Avec ce mode de commande, les contacts du disjoncteur haute tension (2) n'ont pas besoin d'être soumis à une très forte pression d'application car la haute tension, au contraire des tensions de chauffage déjà enclenchées, n'est pas enclenchée en charge. L'ensemble de la structure est considérablement simplifié car le disjoncteur haute tension à des dimensions mécaniques réduites et nécessite seulement un électro-aimant de commutation. Avec cette conception, il est possible d'envisager également, du point de vue des techniques d'utilisation, la construction de petits transformateurs haute tension avec disjoncteur haute tension incorporé. (11) or (12) and the desired fireplace. With this mode of control, the contacts of the high-voltage circuit breaker (2) do not need to be subjected to a very high application pressure because the high voltage, unlike the heating voltages already engaged, is not engaged under load. The entire structure is considerably simplified because the high-voltage circuit breaker has reduced mechanical dimensions and only requires a switching electromagnet. With this design, it is also possible to envisage, from the point of view of the techniques of use, the construction of small high voltage transformers with incorporated high voltage circuit breaker.

LISTE DE REFERENCESREFERENCE LIST

1) Générateur de haute tension1) High voltage generator

2) Disjoncteur haute tension2) High voltage circuit breaker

3) Liaison3) Liaison

4) Liaison4) Liaison

5) Ensemble de convertisseurs de chauffage5) Set of heating converters

6) Ensemble de convertisseurs de chauffage6) Set of heating converters

7) Fil de chauffage7) Heating wire

8) Fil de chauffage8) Heating wire

9) Fil de chauffage9) Heating wire

10) Fil de chauffage10) Heating wire

11) Tube à rayons X11) X-ray tube

12) Tube à rayons X 12) X-ray tube

Claims

REVENDICATIONS 1. Appareil de radio-diagnostic pour la réalisation de radiogrammes, comportant au moins un tube à rayons X alimenté en haute tension, qui peut contenir plusieurs fils chauffants qui sont activés par des convertisseurs de chauffage et dont les valeurs de courant de chauffage de repos sont réglables, caractérisé en ce que, pour chaque tube à rayons X raccordé, il est prévu en correspondance aux fils chauffants installés un ou plusieurs convertisseurs de chauffage dans le générateur de haute tension, et les courants de chauffage sont toujours appliqués directement aux fils chauffants des tubes à rayons X et préchauffent constamment les tubes à rayons X dans la condition de repos, et en ce que seulement la haute tension pour tube à rayons X est commandée en correspondance au tube requis.1. Radio diagnostic apparatus for producing radiograms, comprising at least one high-voltage X-ray tube, which may contain several heating wires which are activated by heating converters and whose quiescent heating current values are adjustable, characterized in that, for each X-ray tube connected, one or more heating converters are installed in the high-voltage generator in correspondence with the heating wires, and the heating currents are always applied directly to the heating wires x-ray tubes and constantly preheat the x-ray tubes in the quiescent condition, and in that only the high voltage for x-ray tube is controlled in correspondence with the required tube. 2. Appareil de radio-diagnostic selon la revendication 1, caractérisé en ce que la haute tension de tube à rayons X est commutée de façon unipolaire ou bipolaire.2. Radio diagnostic apparatus according to claim 1, characterized in that the high voltage of the X-ray tube is switched unipolar or bipolar. 3. Appareil de radio-diagnostic selon la revendication 1, caractérisé en ce que, dans des installations à plusieurs postes de travail, tous les tubes à rayons X sont préchauffés avant le début d'émission et le courant de chauffage est augmenté au début de la prise de vue.3. Radio diagnostic apparatus according to claim 1, characterized in that, in installations with several work stations, all the X-ray tubes are preheated before the start of emission and the heating current is increased at the start of the shooting. 4. Appareil de radio-diagnostic selon la revendication 1, caractérisé en ce que le ou les disjoncteurs haute tension sont déposés à l'intérieur du transformateur haute tension. 4. Radio diagnostic apparatus according to claim 1, characterized in that the high voltage circuit breaker (s) are deposited inside the high voltage transformer. 5. Appareil de radio-diagnostic selon les revendications 1 et 3, caractérisé en ce que, pour la commutation de deux tubes, seulement un électro-aimant de commutation est utilisé. 5. Radio diagnostic apparatus according to claims 1 and 3, characterized in that, for switching two tubes, only a switching electromagnet is used.
PCT/FR1988/000595 1987-12-04 1988-12-05 X-ray diagnostic apparatus Ceased WO1989005564A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DEP3741109.8 1987-12-04
DE19873741109 DE3741109A1 (en) 1987-12-04 1987-12-04 X-RAY DIAGNOSTIC APPARATUS

Publications (1)

Publication Number Publication Date
WO1989005564A1 true WO1989005564A1 (en) 1989-06-15

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ID=6341874

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/FR1988/000595 Ceased WO1989005564A1 (en) 1987-12-04 1988-12-05 X-ray diagnostic apparatus

Country Status (3)

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EP (1) EP0388431A1 (en)
DE (1) DE3741109A1 (en)
WO (1) WO1989005564A1 (en)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3783287A (en) * 1972-05-18 1974-01-01 Picker Corp Anode current stabilization circuit x-ray tube having stabilizer electrode
US4072865A (en) * 1976-06-24 1978-02-07 American Radiologic Systems, Inc. Automatic control system
GB2060959A (en) * 1979-10-04 1981-05-07 Picker Corp X-ray tube current control
EP0066928A1 (en) * 1981-06-04 1982-12-15 Philips Patentverwaltung GmbH X-ray generator, generation method and X-ray generator for carrying out this method
EP0149337A2 (en) * 1984-01-16 1985-07-24 Picker International, Inc. X-ray generating apparatus and method of operating an X-ray tube
EP0198741A1 (en) * 1985-03-22 1986-10-22 General Electric Cgr S.A. High-voltage generator and X-ray apparatus
US4775992A (en) * 1986-09-19 1988-10-04 Picker International, Inc. Closed loop x-ray tube current control
JPH0617899A (en) * 1992-07-02 1994-01-25 Minoru Kamimura Speed change gear of u-crank mechanism with combination of epicyclic gear and free wheel

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3783287A (en) * 1972-05-18 1974-01-01 Picker Corp Anode current stabilization circuit x-ray tube having stabilizer electrode
US4072865A (en) * 1976-06-24 1978-02-07 American Radiologic Systems, Inc. Automatic control system
GB2060959A (en) * 1979-10-04 1981-05-07 Picker Corp X-ray tube current control
EP0066928A1 (en) * 1981-06-04 1982-12-15 Philips Patentverwaltung GmbH X-ray generator, generation method and X-ray generator for carrying out this method
EP0149337A2 (en) * 1984-01-16 1985-07-24 Picker International, Inc. X-ray generating apparatus and method of operating an X-ray tube
EP0198741A1 (en) * 1985-03-22 1986-10-22 General Electric Cgr S.A. High-voltage generator and X-ray apparatus
US4775992A (en) * 1986-09-19 1988-10-04 Picker International, Inc. Closed loop x-ray tube current control
JPH0617899A (en) * 1992-07-02 1994-01-25 Minoru Kamimura Speed change gear of u-crank mechanism with combination of epicyclic gear and free wheel

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Patent Abstracts of Japan, volume 9, no. 131 (E-319)(1854), 6 juin 1985; & JP-A-6017899 (TOSHIBA K.K.) 29 janvier 1985 voir le document en entier *
Siemens-Zeitschrift, volume 43, no. 1, 1969, (Erlangen, DE), E. Braun et al.: "Hochspannungserzeuger für Röntgenanlagen", pages 24-29 *

Also Published As

Publication number Publication date
EP0388431A1 (en) 1990-09-26
DE3741109A1 (en) 1989-06-15

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