EP0320353B1 - Motorisierte Abstimmungsvorrichtung für voreingestellte Frequenzwerte eines Klystrons - Google Patents

Motorisierte Abstimmungsvorrichtung für voreingestellte Frequenzwerte eines Klystrons Download PDF

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Publication number
EP0320353B1
EP0320353B1 EP88403065A EP88403065A EP0320353B1 EP 0320353 B1 EP0320353 B1 EP 0320353B1 EP 88403065 A EP88403065 A EP 88403065A EP 88403065 A EP88403065 A EP 88403065A EP 0320353 B1 EP0320353 B1 EP 0320353B1
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EP
European Patent Office
Prior art keywords
plate
carriage
spring
screws
motor driven
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 - Lifetime
Application number
EP88403065A
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English (en)
French (fr)
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EP0320353A1 (de
Inventor
Michel Bres
François Tisserand
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Thales SA
Original Assignee
Thomson CSF SA
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Publication date
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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
    • H01J23/18—Resonators
    • H01J23/20—Cavity resonators; Adjustment or tuning thereof
    • H01J23/213—Simultaneous tuning of more than one resonator, e.g. resonant cavities of a magnetron

Definitions

  • the present invention relates to a motorized device with preset frequency chords for a klystron.
  • This device uses a known mechanical base of pistons more or less sunk into the resonant cavities of a klystron, these pistons being extended by rods, pushed by springs against adjusting screws carried by a carriage. It has the particularity of not adopting the same locking position, at different frequencies, for the plate on which the springs are supported which keep the rods of each piston in contact with the adjustment screws. This makes it possible to use shorter, less bulky springs, which work at their optimum compression value.
  • electrical switches integrated in the mechanical assembly control the respective positions of the moving parts and ensure the positioning of the plate, and the operational safety of the assembly.
  • Klystrons are microwave generators with cavities. To obtain high power, it is known to associate a plurality of resonant cavities, of which a movable wall is constituted by a piston which, by its displacement, makes it possible to vary the volume of the cavity, and consequently the frequency of the klystron. .
  • the instantaneous bandwidth of a klystron is much lower than the mechanical tuning range, the frequency range in which it is possible to operate it.
  • its tuning range of 500 MHz can be divided into 12 channels, the bandwidth and 45 MHz each.
  • a commonly used method consists in moving, in resonant cavities of rectangular sections, a piston ensuring electrical contact with the sides and which behaves like a movable wall of the cavity. Vacuum tightness is ensured by a deformable metal bellows, placed at the rear of the piston and welded on the edges of the cavity and on the rod which extends the piston.
  • Each bandwidth or channel corresponds to a different position for each piston.
  • the pistons are integral with a rod which can be driven by a screw thread. It is then necessary, at each change of channel, to make as many adjustments as there are pistons and therefore cavities. This is the process that is usually used for large klystron tubes.
  • the springs one end of which is always in the same locking position, must be long enough to exert a suitable pressing force in the two extreme cases of the longest adjusting screws, corresponding to the high frequencies, and the shortest adjusting screws corresponding to the low frequencies. They are therefore bulky.
  • the motors are programmed without knowing the mechanical state of the storage device, since it is purely mechanical and does not include any sensor: if an incident occurs, such as blocked pistons, carriage with screw in an intermediate position. .. etc, the action of electric motors can cause deterioration of at least the mechanical memorization device, and in certain cases of the cavity of the klystron also.
  • the device according to the invention overcomes this drawback, by intelligent control of the motors.
  • Electrical contactors integrated into the device control the position of the moving mechanical parts, and control the operation of the motors.
  • two contactors monitor the position of the two ends of each spring: they stop the locking motor as soon as all the springs have reached a length which corresponds to an optimum compression ratio. This means that the springs are short and that it is the plate on which the springs are supported which is locked in a locking position specific to each frequency: the movement of the plate compensates for the lack of movement of short springs.
  • the invention relates to a motorized device with preset frequency chords for a klystron, comprising a plurality of resonant cavities, each being adjusted in frequency by means of a piston secured to a rod whose position is controlled by a spring which, resting on a plate, exerts its force on a cup integral with the rod and locks the rod against the head of an adjustment screw, this device being characterized in that, whatever the agreement of frequency chosen, and for each cavity, the distance between the plate and the screw head adjustment is constant, the locking position of the plate being movable according to the chosen frequency, and the spring being compressed between the plate and the cup in a constant manner.
  • FIG. 1 represents the section of a klystron which is composed of a plurality of resonant cavities 1.
  • the number of resonant cavities represented here is not limiting of the scope of the invention.
  • the same plurality of pistons 2 are moved inside these cavities: these pistons are presented as cylinder elements, and the contact Electricity between the piston and the walls of the cavity is ensured by a set of metal springs.
  • Each piston is extended towards the outside of the resonant cavity by a rod 3, and the vacuum tightness, which prevails inside the resonant cavity, is obtained by means of a bellows 4 welded on the one hand to the wall of the resonant cavity and on the other hand on the rod 3.
  • each rod 3 comprises a ring 5, on which is supported, when necessary, a plate 6.
  • This plate serves as a support base for as many springs as there are rods 3, and each spring pushes on the corresponding rod 3 by means of a cup 8 which is welded to the rod 3.
  • This system allows the rods 3 to be pressed against screws which serve as a stop, these screws themselves being positioned to adjust the pistons 2 inside the resonant cavities 1 at a given frequency.
  • the rods 3 are supported at their free ends by a plate 9 which allows them to be aligned on the adjustment screws.
  • a mobile carriage 10 which is either in the form of a rectangular carriage animated by a movement of lateral displacement, or in the form of a revolver rotating around its central axis, carries adjustment screws 11. There are, for each frequency, as many screws 11 as resonant cavities and rods 3, and the number of screws is therefore equal to the product of the number of channels to be adjusted by the number of resonant cavities. In Figure 1 four resonant cavities are shown and if the klystron must be adjusted for 6 channels for example the number of screws is equal to 24.
  • Figure 1 the mechanical device for memorizing the position of the pistons is shown in the unlocked position, that is to say that the plate 6 pushes the pistons 2 back into the bottom of the resonant cavities 1, by leaning on the rings 5 integral with the rods 3.
  • these rods 3 are distant from the adjustment screws 11, which allows at this time to present another set of adjustment screws 11, which are further away.
  • the displacement of the plate 6 is obtained by means of a set of threaded rods 12, which are supported on the mechanical chassis which provides rigidity to the assembly.
  • FIG. 2 represents a set of pistons, rods, adjusting screws and springs, taken in isolation, and seen in plan.
  • This figure highlights, on the one hand, two adjusting screws 11, one of which, short, corresponds to a piston which is very prominent relative to the resonant cavity 1, therefore at a low frequency, while the other screw, long, corresponds to a piston depressed therefore at a high frequency since the cavity is smaller.
  • position b the position which corresponds to a low frequency
  • position h that which corresponds to a high frequency.
  • this Figure 2 shows the entire mechanism in the position d, that is to say unlocked, according to which the plate 6 pushes the pistons 2 and the rods 3 so as to ensure decoupling between the rod 3 and any of adjusting screw 11 among all those which are supported by the carriage 10.
  • Figures 3 and 4 show the same elements as those shown in Figure 2, but in the positions corresponding to the high frequency in Figure 3 and the low frequency in Figure 4.
  • High frequency requires a small resonant cavity, so a piston 2 pressed into the resonant cavity, that is to say another adjusting screw 11 which is long.
  • the position of the plate 6 is the same, in lockout - position V -, whatever the frequency, that is to say also the length of the adjustment screws 11. Consequently, if the adjustment screws 11 are long, the cup 8 crushes the spring 7.
  • this spring must be sufficiently compressed to overcome the friction forces between the piston and the walls of the cavity and ensure good contact on the screws. It must therefore be long, but if it is long the spring compressed in FIG. 3 must not exert excessive force. All of this leads to an increase in the size of the mechanism, since the springs must have a long length at rest relative to their travel. This drawback becomes excessive for the tubes working at low frequency, around 2 or 3 GHz: the pistons and the cavities are large in size, so they exert significant friction. If the mechanical tuning range is large, for example 1.7 to 2.4 GHz, we are forced to use long springs of large diameter and large module.
  • the invention consists in not adopting the same locking position V for the plate 6, for all the channels, in order to limit the stroke of the springs.
  • the springs are shorter, less bulky, and they work in a field corresponding to the optimum of their mechanical characteristics.
  • the difference in positioning of each of the rods 3 relative to the adjustment screws 11, between the shortest and the longest, is no longer compensated by the elongation or the compression of the spring 7, but by the difference in the locked position. of the plate 6, which supports the springs 7.
  • the distance which separates the plate 6 from an adjusting screw head 11 is constant: if the position of the screw head 11 changes, the position of the plate 6 changes , but the spring 7 is compressed constantly.
  • FIG. 5 gives a side view of the device for memorizing preset frequency chords according to the invention. Part of this device is visible in Figure 5, while another part is more easily visible in Figure 6 which gives a plan view.
  • the device according to the invention uses the mechanical assembly which is known and which has just been explained in FIG. 1 but it supplements it by two electric motors 14 and 15.
  • the motor 14 is a locking and unlocking motor, and it acts on the set of threaded rods 12 which move the plate 6 relative to the carriage 10 which supports the adjustment screws. The play of this mechanism will be explained in Figure 6.
  • the motor 15 is a channel change motor: by means of a gear carried by its axis, and in connection with a rack supported by the side of the carriage 10 this motor 15 moves the carriage and has before the rods 3 a set of adjusting screws 11.
  • a control unit which is not shown in FIG. 5, allows the motor electric 15 to turn in one direction or another until one of the switches 17 which corresponds to the desired channel for the klystron indicates to the control unit that the position of the carriage 10 is reached. This is easily obtained by means of blade switches, the end of the arm of which carries a caster which falls into a notch engraved in the carriage 10.
  • Figure 6 allows a better view of the locking-unlocking by means of the motor 14. This figure also highlights the presence of a switch 18 secured to the mechanical frame, and a switch 19 for each spring, that is that is to say for each piston 2.
  • the switch 18 is integral with the mechanical frame of the tuning device, and it acts when the carriage 6 reaches the end of its travel in the unlocked position.
  • the switch 19 is fixed on the carriage 6, and it acts in combination with the cup 8, that is to say that this switch switches position when the spring 7 has reached a certain length, which is indicated to it by the cup rim 8.
  • the operation of the device is as follows. To change the channel, firstly the locking-unlocking motor 14, by means of the threaded rods 12, pushes the plate 6 to the unlocked position marked d. The end of stroke signal is given by the switch 18. The pistons are pressed into the resonant cavities and the rods 3 are no longer in contact with the adjusting screws 11, as shown in FIG. 6 and in FIG. 7. As in the known art, the unlocking position d is always the same, the pistons being depressed to the maximum.
  • the channel change motor 15 rotates in a suitable direction, according to the order given to it by the control unit, until one of the switches 17, corresponding to the desired channel indicated to it by the control unit, is triggered according to the position of the carriage 10, corresponding to the desired channel.
  • the locking-unlocking motor 14 then rotates in the opposite direction to that which it had at first.
  • the plate 6 moves away from the klystron and drives the rods 3 via the springs 7, which press on the cups 8.
  • the spring 7 is compressed under the effect of the displacement of the plate 6.
  • the switch 19 fixed on the plate 6 is sufficiently close to the cup 8 to switch.
  • all of the adjustment screws are substantially the same length, within a range of about 1 mm.
  • the locking position V is therefore not fixed, it depends on the channel and is reached as soon as all the springs 7 are sufficiently compressed to ensure sufficient pressure between the rods 3 and the adjusting screws 11. This compression is very close to the desired optimal value, the cups triggering their switch within a displacement range of about 1 mm.
  • the invention applies to the motorization of preset frequency agreements for power klystrons, in the field of microwave generators for radio communications, or radars. It is specified by the following claims.

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  • Control Of Motors That Do Not Use Commutators (AREA)
  • Microwave Tubes (AREA)

Claims (7)

1. Motorisierte Vorrichtung für voreingestellte Frequenzabstimmungen für ein Klystron, mit einer Mehrzahl von Hohlraumresonatoren (1), von denen jeder in bezug auf seine Frequenz mittels eines Kolbens (2) eingestellt wird, wobei der Kolben mit einem Stift (3) verbunden ist, dessen Position von einer Feder (7) gesteuert wird, die, indem sie sich auf einer Platte (6) abstützt, ihre Kraft auf einen mit dem Stift (3) verbundenen Teller (8) ausübt und den Stift (3) gegen den Kopf einer Einstellschraube (11) verriegelt, wobei diese Vorrichtung dadurch gekennzeichnet ist, daß für jede beliebige gewählte Frequenzabstimmung und für jeden Hohlraum der Abstand, der die Platte (6) vom Kopf der Einstellschraube (11) trennt, konstant ist, wobei die Verriegelungsposition der Platte (6) entsprechend der gewählten Frequenz beweglich ist und wobei die Feder (7) zwischen der Platte (6) und dem Teller (8) auf konstante Weise zusammengedrückt wird.
2. Motorisierte Vorrichtung gemäß Anspruch 1, dadurch gekennzeichnet, daß ein erster Elektromotor (14) die Verschiebung der beweglichen Platte (6) durch die Dazwischensetzung wenigstens eines mit einem Gewinde versehenen Stifts (12) gewährleistet und daß ein elektrischer Unterbrecher (18), der mit der Wand des Klystrons verbunden ist, das Ende des Motorhubes (14) in der entriegelten Position festlegt, in der die Kolben (2) in die Hohlräume (1) eingeschoben sind und die Stifte (3) von den Einstellschrauben (11) entkoppelt sind.
3. Motorisierte Vorrichtung gemäß Anspruch 2, dadurch gekennzeichnet, daß für jeden Hohlraum ein elektrischer Unterbrecher (19), der an einer beweglichen Platte (6) befestigt ist, die Kompression der Feder (7) steuert, indem der Teller (8) dazwischengestzt wird, dessen Verschiebung in bezug auf die Platte (6) ein Umlegen des Schalters (19) bewirkt und die verriegelte Position der Vorrichtung, in der die Stifte (3) mit den Einstellschrauben (11) in Kontakt sind, bestimmt.
4. Motorisierte Vorrichtung gemäß Anspruch 3, dadurch gekennzeichnet, daß die Mehrzahl der elektrischen Unterbrecher (19), die der gleichen Mehrzahl von Hohlräumen (1) entspricht, eine logische UND-Schaltung bilden, die die Versorgung des Verriegelungs-/Entriegelungs-Elektromotors (14) unterbricht.
5. Motorisierte Vorrichtung gemäß Anspruch 1, in der die Einstellschrauben (11) von einem Schlitten (10) getragen und in Reihen verteilt sind, die jeweils so viele Schrauben (11) umfassen, wie Hohlräume (1) vorhanden sind, dadurch gekennzeichnet, daß der Schlitten (10) von einem zweiten Elektromotor (15) verschoben wird und daß eine Mehrzahl von elektrischen Unterbrechern (17) die Verschiebung des Schlittens (10) steuern, wobei jeder Unterbrecher (17) mit einer Rille zusammenwirkt, die im Schlitten (10) an einer Position eingraviert ist, die die Ausrichtung einer Reihe von Einstellschrauben (11) mit den die Kolben verlängernden Stiften (3) sicherstellt.
6. Motorisierte Vorrichtung gemäß Anspruch 5, dadurch gekennzeichnet, daß so viele Unterbrecher (17) zur Steuerung der Verschiebung des Schlittens (10) vorhanden sind, wie Reihen von Einstellschrauben (11) und voreingestellte Frequenzabstimmungen vorhanden sind.
7. Motorisierte Vorrichtung gemäß Anspruch 5, dadurch gekennzeichnet daß die Verschiebung des Schlittens (10) außerdem von wenigstens einem Sicherheitsunterbrecher (17a) gesteuert wird, der an den Enden der Hübe des Schlittens (10) angeordnet ist.
EP88403065A 1987-12-08 1988-12-05 Motorisierte Abstimmungsvorrichtung für voreingestellte Frequenzwerte eines Klystrons Expired - Lifetime EP0320353B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8717053 1987-12-08
FR8717053A FR2624322B1 (fr) 1987-12-08 1987-12-08 Dispositif motorise d'accords de frequence preregles pour klystron

Publications (2)

Publication Number Publication Date
EP0320353A1 EP0320353A1 (de) 1989-06-14
EP0320353B1 true EP0320353B1 (de) 1991-11-13

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Application Number Title Priority Date Filing Date
EP88403065A Expired - Lifetime EP0320353B1 (de) 1987-12-08 1988-12-05 Motorisierte Abstimmungsvorrichtung für voreingestellte Frequenzwerte eines Klystrons

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US (1) US4908549A (de)
EP (1) EP0320353B1 (de)
JP (1) JPH01243342A (de)
DE (1) DE3866222D1 (de)
FR (1) FR2624322B1 (de)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5065109A (en) * 1990-10-16 1991-11-12 Varian Associates, Inc. Electropneumatic band selector
JP2541035Y2 (ja) * 1990-10-04 1997-07-09 日本電気株式会社 大電力クライストロン用同調機構
US5422540A (en) * 1992-01-30 1995-06-06 Nec Corporation High power klystron tuning mechanism having means for detecting non-synchronous tuning channel conditions
RU2134919C1 (ru) * 1994-09-28 1999-08-20 АО "Плутон" Устройство ларина для перестройки частоты свч прибора
FR2754384B1 (fr) * 1996-10-04 2004-07-16 Thomson Tubes Electroniques Dispositif d'accord en frequence rapide pour tube hyperfrequence et tube hyperfrequence equipe de ce dispositif
GB2452293B (en) * 2007-08-30 2011-09-28 Isotek Electronics Ltd A tuneable filter and a method of tuning such a filter
CN109219227B (zh) * 2018-11-01 2021-07-27 中国科学院近代物理研究所 调谐装置及具有其的超导加速腔

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3617799A (en) * 1968-06-21 1971-11-02 Varian Associates Gang tuner for a multicavity microwave tube
JPS5544404Y2 (de) * 1974-05-09 1980-10-18
JPS544060A (en) * 1977-06-10 1979-01-12 Nec Corp Klystron of multi-cavity type
JPS5474362A (en) * 1977-11-25 1979-06-14 Nec Corp Multi-cavity klystron
FR2430104A1 (fr) * 1978-06-29 1980-01-25 Thomson Csf Dispositif de selection de la frequence de resonance de cavites hyperfrequences, klystrons et filtres de frequences comportant un tel dispositif
US4546325A (en) * 1984-09-28 1985-10-08 Varian Associates, Inc. Fast-acting tuner for multiple-channel klystrons

Also Published As

Publication number Publication date
DE3866222D1 (de) 1991-12-19
US4908549A (en) 1990-03-13
FR2624322B1 (fr) 1990-03-23
JPH01243342A (ja) 1989-09-28
EP0320353A1 (de) 1989-06-14
FR2624322A1 (fr) 1989-06-09

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