EP0144014A1 - X-ray tube - Google Patents

X-ray tube Download PDF

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Publication number
EP0144014A1
EP0144014A1 EP84113641A EP84113641A EP0144014A1 EP 0144014 A1 EP0144014 A1 EP 0144014A1 EP 84113641 A EP84113641 A EP 84113641A EP 84113641 A EP84113641 A EP 84113641A EP 0144014 A1 EP0144014 A1 EP 0144014A1
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EP
European Patent Office
Prior art keywords
cathode
ray tube
cathode head
tube according
anode
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Granted
Application number
EP84113641A
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German (de)
French (fr)
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EP0144014B1 (en
Inventor
Klaus Dr. Haberrecker
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Siemens AG
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Siemens AG
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Publication of EP0144014A1 publication Critical patent/EP0144014A1/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J35/00—X-ray tubes
    • H01J35/02—Details
    • H01J35/14—Arrangements for concentrating, focusing, or directing the cathode ray
    • H01J35/147—Spot size control
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J35/00—X-ray tubes
    • H01J35/02—Details
    • H01J35/04—Electrodes ; Mutual position thereof; Constructional adaptations therefor
    • H01J35/06—Cathodes
    • H01J35/066—Details of electron optical components, e.g. cathode cups

Definitions

  • the invention relates to an X-ray tube according to the preamble of claim 1.
  • X-ray tubes are known, for example, from US Pat. No. 3,433,955.
  • the cathode opposite the anode in X-ray tubes contains an electron source, which usually consists of a hot cathode (filament).
  • the electron beam emanating from this source is directed onto the focal spot of the anode by means of a focusing device (Wehnelt cylinder).
  • the glow plug usually consists of a wire that is wound like a coil spring and is called a coil.
  • the hot cathode is usually located in a recess (cathode die) of a metal part (cathode head) which has the same potential as it itself. As a result, the electron beam is held together and shaped in the desired manner.
  • an elongated focal spot which originates from an incandescent filament which is arranged in a groove-like depression in the cathode head.
  • an incandescent filament which is arranged in a groove-like depression in the cathode head.
  • the invention has for itself the task in an X-ray tube according to the preamble of claim 1 improve focus, especially with small focal spots, and increase focus stability. This object is achieved by the measures specified in the characterizing part of claim 1.
  • ferromagnetic material the Curie point of which is above 700 ° C
  • stainless steel can be used as the material of the aforementioned type, it is then better possible to connect the parts of the cathode by welding or soldering. As a result, the heat-conducting contact of the parts of the cathode with one another is significantly improved, so that the heat is better distributed compared to known cathodes and no overheating occurs.
  • an X-ray tube of the focusing head reaches in cathode customary mechanical construction temperatures of 800 to 850 ° C.
  • tubes with a metallic central part can reach the anode plate fro in operation 1000 0 C and more the heating by filament and reheat.
  • the use of a direct metallic connection, such as a welded or soldered construction, according to the invention lowers the temperature of the cathode head by approximately 150 ° C., so that the Curie point is no longer exceeded when using ferromagnetic stainless steel.
  • Remanit 4006 or. "4016”
  • the former is specified in DIN 17 440, edition 12.72 as material no. 1.4006 or short name X 10 Cr 13, which is a steel that contains 0.08 to 0.12% carbon and 12 to 14% chromium.
  • Remanit 4016 is described in the aforementioned DIN edition under No. 1.4016 and under the short name X 8 Cr 17 as steel, which has a content of more than 0.1% carbon and 15.5 to 17.5% chromium.
  • the use of the aforementioned materials is also particularly suitable because a favorable transition to the Vacon 10, a so-called melting alloy, which is often used for melting with glass and ceramics, the main components of which, in addition to iron, are 28% nickel and 18% cobalt.
  • the thermal expansion behavior of the steels mentioned matches that of the alloy better than is the case with nickel.
  • the X-ray tube denoted by 1 in FIG. 1 contains the cathode 3 and the anode 4 at the two opposite ends of its bulb 2.
  • the cathode 3 is fastened via an attachment 5.
  • the cathode head 6 is attached to the extension 5 via an intermediate member 7.
  • the heating coil 8 (FIG. 2) is located in a recess in the cathode head 6.
  • An electron beam 9 emanates from it and strikes the focal spot 10 of the anode plate 11 and triggers X-rays 12 there.
  • the anode 11 is set in rotation about the axis 13 by means of a rotor 12 during operation in a known manner by means of a stator (not shown in the figure).
  • the operating voltage of the X-ray tube is applied between the nozzle 15 and one of the lines 16 and 17.
  • the heating voltage of the hot cathode 8 is applied between the lines 16 and 17.
  • the connection 18 at part 7 also gives the cathode head 6 cathode voltage, so that the electrons of the beam 9 emanating from the hot cathode 8 are focused on the anode 11 in the desired manner.
  • the cathode head 6 is welded to the intermediate member 7 at its points of use 6.1 and this is soldered to the shoulder 5 at its points of contact 7.1. Through these good heat-conducting connections Temperature of the focusing head significantly reduced, so that the operating temperature remains well below the Curie temperature.

Abstract

Die Erfindung betrifft eine Röntgenröhre (1), deren Kathodenkopf (6) eine Fokussierung des auf die Anode (4) gerichteten Elektronenstrahls (9) bewirkt. Insbesondere bei Röhren mit kleinem, durch den Elektronenstrahl (9) beaufschlagtem Brennfleck (10) ist es erwünscht, die Fokussierung während des Betriebs der Röhre stabil zu halten. Dies wird erfindungsgemäß verbessert, indem der Kathodenkopf (6) aus ferromagnetischem Material hergestellt wird, dessen Curie-Punkt oberhalb 700° C liegt und der mit seiner Halterung (5, 7) am Röhrenkolben (2) direkte, etwa durch Löten oder Schweißen (6.1, 7.1) hervorgerufene metallische Verbindung aufweist. Die Erfindung ist insbesondere zur Anwendung in Drehanoden-Rönntgenröhren für die medizinische Diagnostik geeignet.The invention relates to an x-ray tube (1), the cathode head (6) of which focuses the electron beam (9) directed onto the anode (4). Particularly in the case of tubes with a small focal spot (10) which is impacted by the electron beam (9), it is desirable to keep the focus stable during operation of the tube. This is improved according to the invention in that the cathode head (6) is made of ferromagnetic material, the Curie point of which is above 700 ° C and which, with its holder (5, 7) on the tube bulb (2), is direct, for example by soldering or welding (6.1 , 7.1) has produced metallic connection. The invention is particularly suitable for use in rotating anode X-ray tubes for medical diagnostics.

Description

Die Erfindung betrifft eine Röntgenröhre nach dem Oberbegriff des Patentanspruchs 1. Derartige Röntgenröhren sind etwa bekannt aus der US-PS 34 33 955.The invention relates to an X-ray tube according to the preamble of claim 1. Such X-ray tubes are known, for example, from US Pat. No. 3,433,955.

Die in Röntgenröhren der Anode gegenüberstehende Kathode enthält eine Elektronenquelle, die in der Regel aus einer Glühkathode (Heizfaden) besteht. Der von dieser Quelle ausgehende Elektronenstrahl wird mittels einer Fokussiereinrichtung (Wehneltzylinder) auf den Brennfleck der Anode geleitet. Die Glühkatbode besteht in der Regel aus einem Draht, der nach Art einer Schraubenfeder gewickelt ist und als Wendel bezeichnet wird. Zur Fokussierung liegt die Glühkathode üblicherweise in einer Vertiefung (Kathodengesenk) eines Metallteiles (Kathodenkopf), welches das gleiche Potential aufweist wie sie selbst. Dadurch wird der Elektronenstrahl zusammengehalten und in der gewünschten Weise geformt.The cathode opposite the anode in X-ray tubes contains an electron source, which usually consists of a hot cathode (filament). The electron beam emanating from this source is directed onto the focal spot of the anode by means of a focusing device (Wehnelt cylinder). The glow plug usually consists of a wire that is wound like a coil spring and is called a coil. For focussing, the hot cathode is usually located in a recess (cathode die) of a metal part (cathode head) which has the same potential as it itself. As a result, the electron beam is held together and shaped in the desired manner.

Insbesondere bei Drehanoden-Röntgenröhren wird ein länglicher Brennfleck benutzt, der von einer Glühwendel stammt, die in einer rillenartigen Vertiefung des Kathodenkopfes angeordnet ist. Nach obengenannter US-PS 34 33 955, Spalte 2, Zeilen 55 bis 60, insbesondere57/58, ist angegeben, daß die Anodenstruktur aus Nickel oder einem ähnlichen Material bestehen soll.In particular in the case of rotating anode X-ray tubes, an elongated focal spot is used which originates from an incandescent filament which is arranged in a groove-like depression in the cathode head. According to the above-mentioned US Pat. No. 3,433,955, column 2, lines 55 to 60, in particular 57/58, it is stated that the anode structure should consist of nickel or a similar material.

Die Erfindung hat sich die Aufgabe gestellt, bei einer Röntgenröhre nach dem Oberbegriff des Patentanspruchs 1 die Fokussierung, insbesondere bei kleinen Brennflecken, zu verbessern und die Fokusstabilität zu erhöhen. Diese Aufgabe wird erfindungsgemäß durch die im Kennzeichen des Anspruchs 1 angegebenen Maßnahmen gelöst.The invention has for itself the task in an X-ray tube according to the preamble of claim 1 improve focus, especially with small focal spots, and increase focus stability. This object is achieved by the measures specified in the characterizing part of claim 1.

Durch die Verwendung von ferromagnetischem Material, dessen Curie-Punkt oberhalb von 700° C liegt, ergibt sich eine verbesserte Fokussierung, weil es eine Abschirmung von Magnetfeldern auch bei der Betriebstemperatur der Kathode bewirkt. Da als Material der vorgenannten Art etwa Edelstahl zur Verwendung gelangen kann, ist es dann besser möglich, die Teile der Kathode durch Schweißen oder Löten zu verbinden. Dadurch wird der wärmeleitende Kontakt der Teile der Kathode miteinander wesentlich verbessert, so daß die Wärme im Vergleich zu bekannten Kathoden besser verteilt wird und keine Überhitzung auftritt.The use of ferromagnetic material, the Curie point of which is above 700 ° C, results in improved focusing because it also shields magnetic fields at the operating temperature of the cathode. Since stainless steel can be used as the material of the aforementioned type, it is then better possible to connect the parts of the cathode by welding or soldering. As a result, the heat-conducting contact of the parts of the cathode with one another is significantly improved, so that the heat is better distributed compared to known cathodes and no overheating occurs.

Bei Betrieb einer Röntgenröhre erreicht der Fokussierungskopf in Kathoden üblichen mechanischen Aufbaus Temperaturen von 800 bis bis 850° C. Insbesondere bei Röhren mit metallischem Mittelteil kann die Aufheizung durch Wendel und Rückheizung vom Anodenteller her im Betrieb 10000 C und mehr erreichen. Dabei geht bei Nickel sowie bei ferromagnetischem Edelstahl der Ferromagnetismus verloren, bei Nickel mit einem Curie-Punkt T = 370° C erheblich früher. Durch die erfindungsgemäß vorgesehene Verwendung einer direkten metallischen Verbindung, etwa einer Schweiß- bzw. Lötkonstruktion, wird jedoch die Temperatur des Kathodenkopfes um ca. 150° C abgesenkt, so daß bei Verwendung von ferromagnetischem Edelstahl der Curie-Punkt nicht mehr überschritten wird. Aufgrund des dann auch unter den bekannten Arbeitsbedingungen erhalten bleibenden Ferromagnetismus werden keine Bewegungen des Fokus durch auf die Röhre einwirkende magnetische Felder bewirkt. Dies ist ganz besonders bei Röntgenröhren vorteilhaft, weil bei kleinem Brennfleck diese Bewegung durchaus die Größe des Brennflecks erreichen kann.In operation of an X-ray tube of the focusing head reaches in cathode customary mechanical construction temperatures of 800 to 850 ° C. In particular, in tubes with a metallic central part can reach the anode plate fro in operation 1000 0 C and more the heating by filament and reheat. The ferromagnetism is lost with nickel and with ferromagnetic stainless steel, with nickel with a Curie point T = 370 ° C considerably earlier. However, the use of a direct metallic connection, such as a welded or soldered construction, according to the invention lowers the temperature of the cathode head by approximately 150 ° C., so that the Curie point is no longer exceeded when using ferromagnetic stainless steel. Because of the ferromagnetism which is then retained even under the known working conditions, no movements of the focus are caused by magnetic fields acting on the tube causes. This is particularly advantageous with X-ray tubes, because with a small focal spot this movement can easily reach the size of the focal spot.

Als günstig hat sich die Verwendung von Edelstahl erwiesen, der unter der Bezeichnung "Remanit 4006"bzw. "4016" bekannt ist. Ersterer ist in DIN 17 440, Ausgabe 12.72 als Werkstoff Nr. 1.4006 oder Kurzbezeichnung X 10 Cr 13 angegeben, der ein Stahl ist, der 0,08 bis 0,12 % Kohlenstoff und 12 bis 14 % Chrom enthält. Remanit 4016 ist in vorgenannter DIN-Ausgabe unter der Nr. 1.4016 und unter der Kurzbezeichnung X 8 Cr 17 als Stahl beschrieben, der einen Gehalt von mehr als 0,1 % Kohlenstoff sowie 15,5 bis 17,5 % Chrom aufweist.The use of stainless steel, which is known as "Remanit 4006" or. "4016" is known. The former is specified in DIN 17 440, edition 12.72 as material no. 1.4006 or short name X 10 Cr 13, which is a steel that contains 0.08 to 0.12% carbon and 12 to 14% chromium. Remanit 4016 is described in the aforementioned DIN edition under No. 1.4016 and under the short name X 8 Cr 17 as steel, which has a content of more than 0.1% carbon and 15.5 to 17.5% chromium.

Die Verwendung der vorgenannten Werkstoffe ist auch deshalb besonders geeignet, weil ein günstiger Übergang auf das zur Verschmelzung mit Glas und Keramik häufig benutzte Vacon 10, einer sogenannten Einschmelzlegierung, deren Hauptbestandteile neben Eisen 28 % Nickel, 18 % Kobalt sind, erzielbar ist. Das thermische Ausdehnungsverhalten der genannten Stähle paßt besser zu demjenigen der Legierung als es beim Nickel der Fall ist.The use of the aforementioned materials is also particularly suitable because a favorable transition to the Vacon 10, a so-called melting alloy, which is often used for melting with glass and ceramics, the main components of which, in addition to iron, are 28% nickel and 18% cobalt. The thermal expansion behavior of the steels mentioned matches that of the alloy better than is the case with nickel.

Weitere Einzelheiten und Vorteile werden nachfolgend anhand der in den Figuren dargestellten Ausführungsbeispiele weiter erläutert.

  • In der Figur 1 ist ein Ubersichtsschaubild über eine erfindungsgemäß verbesserte Drehanoden-Röntgenröhre, die teilweise aufgebrochen ist, gezeichnet,
  • in der Figur 2 im Querschnitt die Kathode und
  • in der Figur 3 im Schnitt III-III ein Ausschnitt aus dem in Figur 2 gezeichneten Kathodenkopf.
Further details and advantages are explained further below using the exemplary embodiments illustrated in the figures.
  • FIG. 1 shows an overview diagram of a rotating anode X-ray tube which has been improved in accordance with the invention and which is partially broken open,
  • in Figure 2 in cross section the cathode and
  • in FIG. 3 in section III-III, a detail from the cathode head shown in FIG. 2.

Die in Figur 1 mit 1 bezeichnete Röntgenröhre enthält an den beiden einander gegenüberliegenden Enden ihres Kolbens 2 die Kathode 3 und die Anode 4. Die Kathode 3 ist dabei über einen Ansatz 5 befestigt. Der Kathodenkopf 6 ist über ein Zwischenglied 7 am Ansatz 5 angebracht. Die Heizwendel 8 (Figur 2) befindet sich in einer Ausnehmung im Kathodenkopf 6. Von ihr geht ein Elektronenstrahl 9 aus, der auf den Brennfleck 10 des Anodentellers 11 auftrifft und dort Röntgenstrahlen 12 auslöst. Die Anode 11 wird mittels eines Rotors 12 beim Betrieb in bekannter Weise mittels eines in der Figur nicht dargestellten Stators in Rotation um die Achse 13 versetzt.The X-ray tube denoted by 1 in FIG. 1 contains the cathode 3 and the anode 4 at the two opposite ends of its bulb 2. The cathode 3 is fastened via an attachment 5. The cathode head 6 is attached to the extension 5 via an intermediate member 7. The heating coil 8 (FIG. 2) is located in a recess in the cathode head 6. An electron beam 9 emanates from it and strikes the focal spot 10 of the anode plate 11 and triggers X-rays 12 there. The anode 11 is set in rotation about the axis 13 by means of a rotor 12 during operation in a known manner by means of a stator (not shown in the figure).

Zur Erzeugung von Röntgenstrahlen wird zwischen dem Stutzen 15 und einer der Leitungen 16 und 17 die Betriebsspannung der Röntgenröhre angelegt. Zwischen den Leitungen 16 und 17 wird die Heizspannung der Glühkathode 8 angelegt. Durch die Verbindung 18 am Teil 7 erhält der Kathodenkopf 6 ebenfalls Kathodenspannung, so daß die von der Glühkathode 8 ausgehenden Elektronen des Strahls 9 in der gewünschten Weise auf die Anode 11 fokussiert werden.To generate X-rays, the operating voltage of the X-ray tube is applied between the nozzle 15 and one of the lines 16 and 17. The heating voltage of the hot cathode 8 is applied between the lines 16 and 17. The connection 18 at part 7 also gives the cathode head 6 cathode voltage, so that the electrons of the beam 9 emanating from the hot cathode 8 are focused on the anode 11 in the desired manner.

Der Kathodenkopf 6 ist an seinen Benutzungsstellen 6.1 mit dem Zwischenglied 7 verschweißt und dieses an seinen Berührungsstellen 7.1 mit dem Ansatz 5 verlötet. Durch diese gut wärmeleitenden Verbindungen wird die Temperatur des Fokussierungskopfes deutlich reduziert, so daß die Betriebstemperatur deutlich unter der Curie-Temperatur bleibt.The cathode head 6 is welded to the intermediate member 7 at its points of use 6.1 and this is soldered to the shoulder 5 at its points of contact 7.1. Through these good heat-conducting connections Temperature of the focusing head significantly reduced, so that the operating temperature remains well below the Curie temperature.

Claims (6)

1. Röntgenröhre mit einem eine Elektronenquelle enthaltenden Kathodenkopf, der über eine Halterung am Röhrenkolben gegenüber der Anode angebracht ist, dadurch gekennzeichnet , daß der Kathodenkopf aus ferromagnetischem Material besteht, dessen Curie-Punkt oberhalb 700° liegt und daß er mit seiner Halterung direkt metallisch verbunden ist.1. X-ray tube with a cathode head containing an electron source, which is attached via a holder on the tube bulb opposite the anode, characterized in that the cathode head consists of ferromagnetic material, the Curie point of which is above 700 ° and that it is directly connected to its holder in a metallic manner is. 2. Röntgenröhre nach Anspruch 1, dadurch gekennzeichnet , daß die direkte metallische Verbindung eine Lötung oder Schweißung ist.2. X-ray tube according to claim 1, characterized in that the direct metallic connection is a soldering or welding. 3. Röntgenröhre nach Anspruch 1, dadurch gekennzeichnet, daß das Material des Kathodenkopfes ferromagnetischer Edelstahl ist.3. X-ray tube according to claim 1, characterized in that the material of the cathode head is ferromagnetic stainless steel. 4. Röntgenröhre nach Anspruch 3, dadurch gekennzeichnet, daß das Material des Kathodenkopfes Edelstahl der Bezeichnung "Remanit 4006" bzw. "4016" ist, dessen wesentliche Bestandteile neben Eisen 0,08 bis 0,12 % Kohlenstoff und 12 bis 17,5 % Chrom sind.4. X-ray tube according to claim 3, characterized in that the material of the cathode head is stainless steel of the designation "Remanit 4006" or "4016", the essential components of which, in addition to iron, are 0.08 to 0.12% carbon and 12 to 17.5%. Are chrome. 5. Röntgenröhre nach Anspruch 3, dadurch gekennzeichnet, daß von den übrigen Metallteilen der Kathode wenigstens der den Kathodenkopf halternde Ansatz ebenfalls aus ferromagnetischem Edelstahl besteht.5. X-ray tube according to claim 3, characterized in that of the remaining metal parts of the cathode at least the approach holding the cathode head also consists of ferromagnetic stainless steel. 6. Röntgenröhre nach Anspruch 4, dadurch gekennzeichnet, daß alle Metallteile der Kathode aus Remanit 4006 bzw. 4016 bestehen.6. X-ray tube according to claim 4, characterized in that all metal parts of the cathode consist of Remanit 4006 or 4016.
EP84113641A 1983-11-25 1984-11-12 X-ray tube Expired EP0144014B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3342688 1983-11-25
DE19833342688 DE3342688A1 (en) 1983-11-25 1983-11-25 X-RAY TUBES

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Publication Number Publication Date
EP0144014A1 true EP0144014A1 (en) 1985-06-12
EP0144014B1 EP0144014B1 (en) 1988-06-01

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EP84113641A Expired EP0144014B1 (en) 1983-11-25 1984-11-12 X-ray tube

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US (1) US4631744A (en)
EP (1) EP0144014B1 (en)
JP (1) JPS60107566U (en)
DE (2) DE3342688A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE1007372A3 (en) * 1993-07-28 1995-05-30 Philips Electronics Nv X-ray tube with improved heat exchange
US6441004B1 (en) 1997-08-07 2002-08-27 Zeneca Limited Monocyte chemoattractant protein-1 inhibitor compounds

Families Citing this family (5)

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Publication number Priority date Publication date Assignee Title
DE3542127A1 (en) * 1985-11-28 1987-06-04 Siemens Ag X-RAY EMITTER
US6215852B1 (en) * 1998-12-10 2001-04-10 General Electric Company Thermal energy storage and transfer assembly
US7257194B2 (en) * 2004-02-09 2007-08-14 Varian Medical Systems Technologies, Inc. Cathode head with focal spot control
US7661445B2 (en) * 2005-12-19 2010-02-16 Varian Medical Systems, Inc. Shielded cathode assembly
US9524845B2 (en) 2012-01-18 2016-12-20 Varian Medical Systems, Inc. X-ray tube cathode with magnetic electron beam steering

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US2839698A (en) * 1955-07-01 1958-06-17 Gen Electric Electron shielding in X-ray tubes
US3433955A (en) * 1966-09-26 1969-03-18 Picker Corp X-ray generator with emission control arrangement within the focusing cup
US3875028A (en) * 1972-08-30 1975-04-01 Picker Corp Method of manufacture of x-ray tube having focusing cup with non emitting coating
US3962583A (en) * 1974-12-30 1976-06-08 The Machlett Laboratories, Incorporated X-ray tube focusing means
FR2388404A1 (en) * 1977-04-18 1978-11-17 Philips Nv LONG ELECTRON TRAJECTORY RONTGEN TUBE
US4184097A (en) * 1977-02-25 1980-01-15 Magnaflux Corporation Internally shielded X-ray tube

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US2686884A (en) * 1950-05-01 1954-08-17 Dunlec Corp Space charge controlled X-ray tube

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2839698A (en) * 1955-07-01 1958-06-17 Gen Electric Electron shielding in X-ray tubes
US3433955A (en) * 1966-09-26 1969-03-18 Picker Corp X-ray generator with emission control arrangement within the focusing cup
US3875028A (en) * 1972-08-30 1975-04-01 Picker Corp Method of manufacture of x-ray tube having focusing cup with non emitting coating
US3962583A (en) * 1974-12-30 1976-06-08 The Machlett Laboratories, Incorporated X-ray tube focusing means
US4184097A (en) * 1977-02-25 1980-01-15 Magnaflux Corporation Internally shielded X-ray tube
FR2388404A1 (en) * 1977-04-18 1978-11-17 Philips Nv LONG ELECTRON TRAJECTORY RONTGEN TUBE

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE1007372A3 (en) * 1993-07-28 1995-05-30 Philips Electronics Nv X-ray tube with improved heat exchange
US6441004B1 (en) 1997-08-07 2002-08-27 Zeneca Limited Monocyte chemoattractant protein-1 inhibitor compounds

Also Published As

Publication number Publication date
EP0144014B1 (en) 1988-06-01
DE3471816D1 (en) 1988-07-07
JPS60107566U (en) 1985-07-22
US4631744A (en) 1986-12-23
DE3342688A1 (en) 1985-06-05

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