EP0004492B1 - Mikrowellenröhre mit einer durch Fluidumströmung gekühlten Verzögerungsleitung - Google Patents

Mikrowellenröhre mit einer durch Fluidumströmung gekühlten Verzögerungsleitung Download PDF

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Publication number
EP0004492B1
EP0004492B1 EP79400143A EP79400143A EP0004492B1 EP 0004492 B1 EP0004492 B1 EP 0004492B1 EP 79400143 A EP79400143 A EP 79400143A EP 79400143 A EP79400143 A EP 79400143A EP 0004492 B1 EP0004492 B1 EP 0004492B1
Authority
EP
European Patent Office
Prior art keywords
delay line
line
envelope
contact
axis
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.)
Expired
Application number
EP79400143A
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English (en)
French (fr)
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EP0004492A2 (de
EP0004492A3 (en
Inventor
Bernard Delory
Georges Fleury
Jean-Claude Kuntzmann
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.)
Thales SA
Original Assignee
Thomson CSF SA
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Filing date
Publication date
Application filed by Thomson CSF SA filed Critical Thomson CSF SA
Publication of EP0004492A2 publication Critical patent/EP0004492A2/de
Publication of EP0004492A3 publication Critical patent/EP0004492A3/xx
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J23/00—Details of transit-time tubes of the types covered by group H01J25/00
    • H01J23/16—Circuit elements, having distributed capacitance and inductance, structurally associated with the tube and interacting with the discharge
    • H01J23/24—Slow-wave structures, e.g. delay systems
    • H01J23/26—Helical slow-wave structures; Adjustment therefor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J23/00—Details of transit-time tubes of the types covered by group H01J25/00
    • H01J23/005—Cooling methods or arrangements

Definitions

  • the present invention relates to a microwave tube comprising a delay line cooled by fluid circulation.
  • the microwave tubes to which the invention applies such as traveling wave tubes or type 0 carcinotrons, have a delay line ensuring the interaction between an electron beam and an electromagnetic wave: in fact, the electromagnetic wave propagates on the delay line and its phase speed is made comparable to that of the electron beam which moves along the axis of the line.
  • the delay line can have various structures: helical, of the "ring and bar”, “ring and loop” type, according to English terminology ...
  • the invention is particularly applicable to cases where the focusing of the electron beam throughout the interaction space with the electromagnetic wave is carried out by a magnetic field produced by permanent magnets.
  • the invention aims to cool the delay line by fluid: it is the site of high frequency losses and, moreover, poor focusing of the electron beam can increase its heating.
  • the problem which arises is that of the arrangement of the channels where the cooling fluid circulates. This arrangement is easier when the focusing magnetic field of the electron beam is produced by an electromagnet than when it is produced by permanent, larger magnets.
  • focusing by permanent magnets has great advantages in terms of weight and consumption in particular, it is important to have the cooling channels as best as possible around a delay line focused by permanent magnets.
  • the cooling fluid circulates in channels, formed by the space between two sleeves, impervious to this fluid, having as axis the axis of the delay line.
  • the first sheath in non-magnetic material, is in contact with the face of rods which is opposite to one face of these rods in contact with the delay line, these rods, in dielectric material, being parallel to the axis of the line and regularly distributed around its perimeter.
  • the first sleeve has no contact with the delay line and seals the vacuum created in its internal volume.
  • the second sleeve contains the first with which it is in contact at different points constituting the separation between the channels in which the cooling fluid circulates.
  • the arrangement of the cooling channels according to the invention ensures cooling of the delay line more efficient than that which is achieved by the known arrangements. It allows in particular the cooling of a delay line operating in band I, for which the known arrangement which has just been mentioned is not applicable since it does not make it possible to obtain the focusing field of the beam d 'electrons.
  • the arrangement according to the invention does not cause, like the known arrangements, a significant increase in the volume of the tube.
  • FIGS. 1 a and 2 is shown, by way of example, a cross section of a microwave tube comprising a delay line cooled by circulation of fluid, of the prior art, the electron beam being focused by magnets permanent.
  • the delay line 1 which is represented has a circular section: it can be helical for example.
  • Three rods, identified by 2, made of dielectric material and good thermal conductor, such as alumina, quartz, boron nitride, glucine, are regularly distributed on the delay line. They are parallel to the axis of the line. It is known to braze these rods by one of their faces on the line in order to reduce the thermal resistance at the interface between the line and the rods.
  • FIG. 1b represents a longitudinal section of a microwave tube comprising a delay line along AA 'of FIG. 1a.
  • the focusing device by permanent magnets is adjusted on the cylindrical sheath 3. It is constituted by an alternating sequence along the axis of the line 1 of permanent magnets 4 and of polar masses 5, the faces of the same name of the magnets being opposite.
  • a collar 6 made of a material which is a good conductor of heat, copper for example, encircles the focusing device; it is crossed by channels 7 where the cooling fluid which is generally a liquid circulates.
  • this arrangement of the cooling channels does not ensure effective cooling of the delay line because the thermal resistance between the line and the channels is high: the focusing device is generally not soldered on the sheath 3 and the thermal resistance of the focusing device is important.
  • the collar 6 supporting the cooling channels 7 is adjusted on the sheath 3.
  • the collar and the channels must be made of magnetic material and good conductor of heat, copper for example.
  • the focusing device consisting of permanent magnets 4 and polar masses 5 encircles the flange 6. As has been said previously, this arrangement decreases, compared to the previous one, the thermal resistance between the line 1 and the channels 7; it therefore improves the cooling of the line, but it has the disadvantage of making it more difficult and sometimes impossible, the production of the focusing device by permanent magnets.
  • the cooling fluid of the delay line circulates in channels formed by the space between two sheaths sealed to this fluid, having for axis the axis of the line.
  • a first sheath plays the role filled in the arrangements described above by the cylindrical sheath 3: it is non-magnetic and ensures the vacuum tightness produced in its internal volume, it is in contact with the face of rods, made of dielectric material, which is opposite to one face of these rods in contact with the delay line, these rods being parallel to the axis of the line and regularly distributed around its periphery; this first sleeve has no contact with the delay line.
  • the first sheath according to the invention is distinguished from the sheaths 3 known by its section which is not necessarily circular.
  • the second sleeve contains the first with which it is in contact at different points constituting the separation between the channels in which the cooling fluid circulates.
  • the second sheath is generally a cylinder, made of non-magnetic material, on which is mounted a focusing device by permanent magnets.
  • the circular section of this second sheath allows the use of permanent magnet washers, this shape of the magnets being necessary for the proper focusing of the electron beam.
  • FIG. 3 shows, by way of example, a cross section of a microwave tube comprising a delay line, cooled by circulation of fluid according to the invention, the electron beam being focused by permanent magnets.
  • 1 be the delay line which can be helicoidal and 2 rods regularly distributed, generally three in number, made of dielectric material and good conductor of heat.
  • the rods 2 can be brazed on the line by one of their faces and brazed by their face opposite to that which is brazed on the line with the first sleeve 8.
  • the contact between the rods 2 and the line 1 on the one hand, the sleeve 8 on the other hand, can also be carried out by adjusting the sheath 8 on the rods.
  • the first sheath 8 covers the face of each rod opposite the face in contact with the line and then connects two adjacent rods in a straight line, it is therefore substantially triangular.
  • the second sleeve 9 is cylindrical and contains the first with which it is in contact at different points.
  • the first sheath 8 and the second sheath 9 are made of non-magnetic material, for example copper.
  • the technological realization of the assembly of the two sheaths represented by FIG. 3 can be as follows: two copper tubes, one circular, the other substantially triangular are brazed simultaneously with the rods 2 and the line 1.
  • the contact between the two sleeves 8 and 9 can therefore be achieved by brazing, but also by adjusting the cylindrical sheath 9 on the first sheath 8.
  • the cooling fluid circulating in the channels 10 formed by the space between the sleeves 8 and 9 can be water.
  • the first sheath 8 is made of non-magnetic material, a good thermal conductor, but not metallic, the cooling fluid must be dielectric.
  • the focusing device consisting of permanent magnets 4 and polar masses 5 is adjusted on the cylindrical sheath 9.
  • the thermal resistance between the delay line 1 and the channels 10 where the cooling fluid circulates is obviously lower with the arrangement according to the invention than with the known arrangements.
  • the brazing of the rods on the line and on the first sleeve contributes to reducing this thermal resistance.
  • the cooling of the delay line according to the invention is therefore effective.
  • the first sheath 8 does not appreciably modify the microwave characteristics of the delay line as long as the helix-mass capacity remains low. It is known that the introduction between two dielectric rods of a large helix-mass capacity modifies the microwave characteristics and in particular reduces the dispersion of the delay line. If, to widen the high frequency band, a reduction in the dispersion of the delay line is desired, the distance d between the line and the wall of the first sheath 8, in the zone where it is not in contact with an electrical rod, must be decreased. It should be noted that this reduction in the dispersion of the delay line is accompanied by a reduction in its efficiency, which is a drawback.
  • the arrangement of the cooling channels according to the invention increases only slightly (by the thickness of the first sleeve 8) the internal diameter of the focusing device shown in FIG. 1. Thus the drawbacks linked to the arrangement shown in the figure are avoided.
  • FIG. 2. The arrangement according to the invention of the cooling channels of a delay line makes it possible to reduce the space requirement of the tube required by the arrangements of known cooling channels by 30 to 40%: this reduction in volume is significant, d 'especially since these tubes are frequently airborne.
  • the cooling channels 10 are connected to circuits for supplying and discharging the cooling fluid. These connections can be made by piercing the focusing system. It is however more advantageous to place them between the flanges of the tube, next to the barrel which produces the electron beam and next to the collector which receives this beam.
  • Figure 4 is shown a longitudinal section of a variant of a microwave tube having a delay line cooled by fluid circulation according to the invention.
  • the second sleeve the role of which is to seal the cooling fluid and to ensure, when the focusing is done by permanent magnets, to the line assembly, first sleeve, cooling channels, an envelope cylindrical which supports the focusing device, is modified.
  • the second sheath shown in Figure 4 where it is generally identified by 12, has the originality of containing the polar masses 5 of the focusing device by permanent magnets.
  • the second sheath 12 is constituted by an alternating series along the axis of the delay line of cylinders made of non-magnetic material 11, for example of copper and cylinders made of magnetic material, welded end to end.
  • the cylinders made of magnetic material also carry a flange made of magnetic material in their middle and constitute the polar masses 5 of the focusing device. Washers of permanent magnets 4 are inserted between two successive flanges, the faces of the same name of the magnets being opposite.
  • the second sheath 12, like the second sheath 9, can be in contact with the first sheath 8 by brazing or simply by adjustment on the first sheath 8.
  • This variant has the advantage of reducing the internal diameter of the focusing device, therefore that of the permanent magnet washers 4: at high frequencies, bands I and J for example, we have seen that it is advantageous to reduce this as much as possible. diameter.
  • This variant also has the advantage of further contributing to the reduction in volume of the microwave tube.

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  • Microwave Tubes (AREA)
  • Particle Accelerators (AREA)

Claims (7)

1. Höchstfrequenzröhre mit einer durch Fluidzirkulation gekühlten Verzögerungsleitung, welche die Wechselwirkung zwischen einem Elektronenbündel und einer sich auf der Leitung fortpflanzenden elektromagnetischen Welle gewährleistet, wobei das Elektronenbündel entlang der Achse der Leitung durch eine Fokussiervorrichtung fokussiert ist, dadurch gekennzeichnet, daß das Kühlfluid in Kanälen (10) zirkuliert, die durch den Raum zwischen zwei für dieses Fluid dichten Hüllen gebildet sind, deren Achse die Achse der Verzögerungsleitung (1) ist, wobei die erste, aus unmagnestischem Material gebildete Hülle (8) in Berührung mit derjenigen Seite von Stäbchen (2) ist, die einer Seite dieser Stäbchen gegenüberliegt, welche in Berührung mit der Verzögerungsleitung ist, wobei diese aus dielektrischem Material gebildeten Stäbchen parallel zur Achse der Verzögerungsleitung und regelmäßig um ihren Umfang herum verteilt sind, wobei die erste Hülle keinerlei Berührung mit der Verzögerungsleitung aufweist und die Vakuumdichtigkeit in bezug auf das in ihrem Innere hergestellte Vakuum gewährleistet, und wobei die zweite, die erste enthaltende Hülle, mit der sie an verschiedenen Punkten in Berührung ist, die Trennung zwischen den Kanälen (10) bildet, in denen das Kühlfluid zirkuliert.
2. Höchstfrequenzröhre nach Anspruch 1, dadurch gekennzeichnet, daß die zweite Hulle (9) ein Zylinder aus unmagnetischem Material ist, auf dem eine Permanentmagnet-Fokussiervorrichtung montiert ist, die gebildet ist aus einer entlang der Achse der Leitung (1) abwechselnden Folge von Polmassen (5) und Permanentmagneten (4), wobei die Flächen gleicher Bezeichnung der Magneten einander gegenüberliegen.
3. Höchstfrequenzröhre nach Anspruch 1, dadurch gekennzeichnet, daß die zweite Hülle (12) gebildet ist aus einer längs der Achse der Verzögerungsleitung (1) abwechselnden Folge von Zylindern (11) aus unmagnetischem Material und von Zylindern aus magnetischem Material, die Ende an Ende aneinandergeschweißt sind, wobei die Zylinder aus magnetischem Material in ihrer Mitte einen Kragen aus ebenfalls magnetischem Material tragen und die Polmassen (5) der Permanentmagnet-Fokussiervorrichtung bilden, wobei diese Vorrichtung ferner Permanentmagnetringe (4) umfaßt, die zwischen zwei aufeinanderfolgende Kragen eingefügt sind, wobei die Seiten gleicher Bezeichnung der Magneten einander gegenüberliegen.
4. Höchstfrequenzröhre nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, daß der Kontakt zwischen den Stäbchen (2) und der Verzögerungsleitung (1) einerseits sowie mit der ersten Hülle (8) andererseits durch Hartlöten gewährleistet ist.
5. Höchstfrequenzröhre nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, daß der Kontakt zwischen der ersten Hülle (8) und der zweiten Hülle durch Hartlöten gewährleistet ist.
6. Höchstfrequenzröhre nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß die Verbindungen zwischen den Kanälen, in denen das Kühlfluid zirkuliert, und die Zufuhrsowie die Abführungsleitungen für dieses Fluid sich durch die Fokussiervorrichtung erstrecken.
7. Höchstfrequenzröhre nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß die Verbindungen zwischen den Kanälen (10), in denen das Kühlfluid zirkuliert, und den Zuführungs- und Abführungsleitungen für dieses Fluid zwischen den Seitenteilen der Röhre neben der das Elektronenbündel erzeugenden Kanone und neben dem dieses Bündel aufnehmenden Kollektor verlaufen.
EP79400143A 1978-03-24 1979-03-06 Mikrowellenröhre mit einer durch Fluidumströmung gekühlten Verzögerungsleitung Expired EP0004492B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7808673A FR2420842A1 (fr) 1978-03-24 1978-03-24 Ligne a retard, pour tube hyperfrequences, refroidie par circulation de fluide et tube hyperfrequences comportant une telle ligne
FR7808673 1978-03-24

Publications (3)

Publication Number Publication Date
EP0004492A2 EP0004492A2 (de) 1979-10-03
EP0004492A3 EP0004492A3 (en) 1979-10-17
EP0004492B1 true EP0004492B1 (de) 1981-12-30

Family

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Application Number Title Priority Date Filing Date
EP79400143A Expired EP0004492B1 (de) 1978-03-24 1979-03-06 Mikrowellenröhre mit einer durch Fluidumströmung gekühlten Verzögerungsleitung

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Country Link
US (1) US4243914A (de)
EP (1) EP0004492B1 (de)
DE (1) DE2961638D1 (de)
FR (1) FR2420842A1 (de)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2907762A1 (de) * 1979-02-28 1980-09-04 Siemens Ag Gasdichte, hochfrequenzdurchlaessige fensteranordnung in einer koaxialleitung, insbesondere fuer wanderfeldroehren
FR2494036A1 (fr) * 1980-11-07 1982-05-14 Thomson Csf Ligne a retard pour tube a ondes progressives, a refroidissement par caloducs, et tube a ondes progressives comportant une telle ligne
FR2501906A1 (fr) * 1981-03-16 1982-09-17 Thomson Csf Procede de fixation des masses polaires a la face externe du fourreau d'un tube a onde progressive et tube obtenu selon un tel procede
DE3407206A1 (de) * 1984-02-28 1985-08-29 Siemens AG, 1000 Berlin und 8000 München Wanderfeldroehre und verfahren zu deren herstellung
DE3501971A1 (de) * 1985-01-22 1986-07-24 Spinner GmbH Elektrotechnische Fabrik, 8000 München Hohlleiterbauelement
JPS62283533A (ja) * 1986-05-31 1987-12-09 Nec Corp 空胴結合型進行波管
FR2647953B1 (fr) * 1989-05-30 1991-08-16 Thomson Tubes Electroniques Mode de construction d'une ligne a retard a helice et tubes a ondes progressives utilisant ce mode de construction
FR2787918B1 (fr) 1998-12-23 2001-03-16 Thomson Tubes Electroniques Tube a ondes progressives multibande de longueur reduite capable de fonctionner a puissance elevee
CN114005720B (zh) * 2021-11-09 2022-10-14 北京航空航天大学 太赫兹行波管慢波聚焦集成结构及其制造方法

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GB707123A (en) * 1952-04-29 1954-04-14 English Electric Valve Co Ltd Improvements in or relating to travelling wave tubes
US2850666A (en) * 1955-12-01 1958-09-02 Hughes Aircraft Co Helix structure for traveling-wave tubes
US3070725A (en) * 1958-03-17 1962-12-25 Eitel Mccullough Inc Travelling wave amplifier
US3216085A (en) * 1961-05-01 1965-11-09 Sylvania Electric Prod Method of making helix assembly
US3271615A (en) * 1961-08-23 1966-09-06 Westinghouse Electric Corp Traveling wave electron discharge device having means exerting a radial force upon the envelope
US3211947A (en) * 1962-05-14 1965-10-12 Bloom Stanley Noise reduction of traveling-wave tubes by circuit refrigeration
US3317780A (en) * 1962-06-25 1967-05-02 Varian Associates Traveling wave tube apparatus
US3274429A (en) * 1963-03-18 1966-09-20 Varian Associates High frequency electron discharge device with heat dissipation means
US3382399A (en) * 1965-05-06 1968-05-07 Army Usa Modified traveling wave tube
GB1195805A (en) * 1967-06-29 1970-06-24 Nippon Electric Co Improvements in or relating to Magnetically Focussed Electron Tube Devices
US3617798A (en) * 1970-07-22 1971-11-02 Us Navy Fluid-cooling slow wave interaction structure for a traveling wave tube
US3670196A (en) * 1971-02-24 1972-06-13 Raytheon Co Helix delay line for traveling wave devices
US4137482A (en) * 1977-05-12 1979-01-30 Varian Associates, Inc. Periodic permanent magnet focused TWT

Also Published As

Publication number Publication date
EP0004492A2 (de) 1979-10-03
FR2420842B1 (de) 1981-05-29
EP0004492A3 (en) 1979-10-17
DE2961638D1 (en) 1982-02-18
FR2420842A1 (fr) 1979-10-19
US4243914A (en) 1981-01-06

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