JPH0537394Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a tuning mechanism for a high-power klystron, and particularly relates to an improvement in the structure of a tuning mechanism for a high-power klystron that amplifies high frequencies in the millimeter wave band.

Conventional technology A high-power klystron consists of an electron gun that forms and emits an electron beam, a high-frequency circuit that interacts high-frequency power with the electron beam, a collector that captures the electron beam, and an electron that passes through the high-frequency circuit. It basically consists of a focusing device that focuses the beam. Among them, the high frequency circuit section is generally formed from a plurality of cavity resonators. A cavity resonator has a resonant cavity main body and a tuning device disposed within the resonant cavity to vary the tuning frequency, and the tuning is provided by a tuning mechanism located outside the cavity resonator. They are connected and supported for displacement within the resonant cavity.

In such a high-power klystron, when varying the frequency of the high-frequency power to be amplified, it is necessary to adjust the tuning frequency to an appropriate value while observing the output waveform of each of the multiple cavity resonators each time. However, similar to high-power klystrons, they are inconvenient to handle compared to traveling wave tubes that amplify high frequencies in the millimeter wave band. Therefore, in order to solve this operational inconvenience, in the past, a preset function was introduced that allows the high-power klystron to easily obtain the specified bandwidth by simply switching the frequency for preset frequencies. A section is provided.

FIG. 2 is a sectional view of a conventional tuning mechanism for a high power klystron equipped with such a preset section. According to the figure, a tuning 3 that changes the tuning frequency by changing the volume of the resonant cavity 2 is disposed inside the cavity resonator 1 of the high-power klystron. It is connected to and supported by the tuner shaft 6 of the tuning mechanism 4 located outside, and is displaced within the resonant cavity 2.

Between the outer wall of the resonant cavity 2 and the tuned flange portion 3A, a high-power klystron including the inside of the cavity resonator 1 is maintained in a vacuum, and the tuned tuning 3 can be displaced by its mechanical deformation. A bellows 5 is connected airtightly.

The end of the tuning mechanism 3 is connected to the end of the tuner shaft 6 with a screw 7. A force is always applied to the tuner shaft 6 due to the restoring force of the spring 8, which tends to pull out the tuner 3 to the outside of the resonant cavity (to the right side in the figure).

That is, the tuner shaft 6, spring 8, etc. form a tuning support mechanism. On the other hand, the tip of the tuner shaft 6 on the opposite side from the tuner shaft 6 is in contact with one of the protrusions made of the adjusting screw 11 or the like. In addition, multiple adjustment screws 11
is screwed into the gear 10 and protrudes toward the synchronization support mechanism. The gear 10 is rotatably attached by a shaft 10A to a fixed plate 9 fixed to the outer wall of the resonant cavity 2 via screws 9A and 9B. The tuning frequency of cavity resonator 1 is the same as that of resonance cavity 2.
Each adjustment screw 1
It is possible to preset each cavity resonator to obtain a specific tuning frequency by one screwing degree. The gears 10 mesh with each other, and one of them meshes with a chain gear 22 mounted on the fixed plate 9 via a bearing 21, and is rotated by rotation of the chain gear 22. There is.

Another fixing plate 13 is fixed at a fixed position between the outer wall of the resonant cavity 2 and the fixing plate 9 via screws 9A and 9B. On the fixed plate 13,
Locking shaft 1 via bearing 14A
5 is installed. The rocking shaft 1
5 has a part that is screwed into the movable plate 17, and an unlocking plate 16 and a locking plate 23 are provided on both sides of the screwing part.
is fixed. Therefore, when the locking shaft 15 is rotated, the movable plate 17 is displaced toward the cavity resonator side (to the left in the figure) until the movable plate 17 contacts the unlocking plate 16, and the movable plate 17 is moved toward the cavity resonator side (left side in the figure) until the movable plate 17 contacts the unlocking plate 16.
The movable plate 17 can be displaced in the opposite direction until the point 7 hits.

Further, a sprocket 18A is fixed to the locking shaft 15. Furthermore, the fixing plate 13
A locking screw 19 is attached to the locking screw 19 via a bearing 14B, and the locking screw 19 also has a portion that screws into the movable plate 17, and an unlocking plate 16 and a locking plate 23 are provided on both sides of the screwing portion. Fixed. And locking screw 19
A sprocket 18B is also fixed to the sprocket. Those sprockets 18A and their sprockets 18
A chain 20 is suspended on B, and the locking screw 19 is rotated by the rotation of the locking shaft 15.
The movable plate 17 is also rotated so that the movable plate 17 is displaced parallel to the fixed plate 13.

In the above configuration, the plurality of adjustment screws 11, gear 10, etc. form a so-called preset section. A preset operation for presetting the tuning frequency of each cavity resonator so that the high-power klystron can easily obtain a specified bandwidth can be performed as follows.

First, in the state shown in Figure 2, the position of the tuning 3 in the cavity resonator is adjusted by rotating the adjustment screw 11A and adjusting the degree of screwing in so that the tuning frequency of the cavity resonator 1 becomes the required value. I do.

Next, remove the locking shaft 15 from the unlocking plate 1.
6 rotates until it hits the movable plate 17, and the movable plate 17 is displaced to the cavity resonator side (left side in the figure). At this time, the sprocket 18B also rotates via the sprocket 18A fixed to the locking shaft 15 and the chain 20, and the locking screw 19
It also rotates. Therefore, the movable plate 17 is the same as the fixed plate 13.
Displaced parallel to. At this time, the tuner shaft 6 contacts the movable plate 17 at the flange portion 6A, and is pushed by the movable plate 17 and displaced toward the cavity resonator, so that the tip of the tuner shaft 6 is sufficiently separated from the adjustment screw 11.

That is, the fixing plate 13, the locking shaft 1
5 and the locking screw 19 form a drive mechanism for mechanically connecting or disconnecting the tuning support mechanism and the preset portion. In this state, the chain gear 22 is rotated, and the gear 10 meshing with the chain gear 22 is rotated. An adjustment screw 11A that is different from the adjustment screw 11 moves to a position that coincides with the central axis of the tuner shaft 6.

Thereafter, the locking shaft 15 is rotated in the opposite direction from the front, and the movable plate 17 moves until it touches the locking shaft 15 and the locking plate 23 of the locking screw 19. With the tip of the tuner shaft 6 in contact with the adjustment screw 11B, turn the adjustment screw 1
By rotating 1B and adjusting the degree to which it is screwed into the gear 10, it is possible to set the cavity resonator 1 to have a different tuning frequency than when using the adjustment screw 11A.

By repeating the above adjustment, a large number of tuning frequencies for each cavity resonator can be set in advance.

Therefore, in order to change the frequency using the tuning mechanism having the preset section set in advance by the above-mentioned adjustment, first, the locking shaft 15 is moved to the unlocking plate 16.
rotates until it touches the movable plate 17, moves the movable plate 17 in parallel toward the cavity resonator 1, and sufficiently separates the tip of the tuner shaft 6 from the adjustment screw. At this time, the bellows is greatly compressed. Next, the change gear 22 is rotated to align the adjustment screws set to other tuning frequencies with the center axis of the tuner shaft. After that, locking shaft 1
5 in the opposite direction from the front and move it until the movable plate 17 hits the lock plate 23, the tip of the tuner shaft 6 comes into contact with the adjustment screw set to the tuning frequency you want to change, and the frequency is switched. It can be performed.

Problems to be Solved by the Invention However, according to the tuning mechanism with the structure described above, each time the tuning frequency of the cavity resonator is changed, the movable plate moves in parallel, and the tuning mechanism continues to the tuner shaft. The tone also changes drastically.

As a result, the bellows, which is formed by press-forming or welding a thin metal plate such as stainless steel, also expands and contracts significantly. As a result, in a period shorter than the original lifespan of the klystron, leakage occurred due to the metal fatigue of this bellows, and the vacuum seal of the high-power klystron was broken, including inside the cavity resonator. had a fatal problem.

Therefore, the present invention is a tuning system for high-power klystrons that solves the above problems and can maintain high-power klystrons mechanically stable at all times without fear of leakage from the bellows even if the frequency is changed frequently. It is intended to provide the structure of the mechanism.

Means for Solving the Problem That is, according to the present invention, a tuner arranged in a cavity resonator and connected to the tuner fixed to the cavity resonator via a bellows, and connected to the tuner It has a tuning support mechanism that always applies a constant force in the axial direction, and a plurality of protrusions whose positions can be mechanically switched, and at least one of the projections is attached to at least a part of the tuning support mechanism. A tuning device for a high-power klystron comprising: a preset portion that contacts and positions the tuning portion at a desired position; and a drive mechanism that mechanically connects or disconnects the tuning support mechanism and the preset portion from contact. In the mechanism, the tuning support mechanism is fixed to an outer wall of the resonant cavity, and the drive mechanism is configured to be able to displace a part or all of the preset section with respect to the tuning support mechanism. Make it.

According to the above, when changing the tuning frequency of the cavity resonator, the preset section is first displaced by the drive mechanism so as to be separated from the tuning support mechanism connected and fixed to the outer wall of the resonant cavity.

Therefore, since there is no need to greatly displace the tuner itself, the bellows will not be greatly expanded or contracted accordingly.

Therefore, according to the present invention, expansion and contraction of the bellows when changing the tuning frequency can be made extremely small. As a result, even when a high-power klystron undergoes numerous frequency changes, the metal that forms the bellows suffers less fatigue.
The risk of leaks occurring in the bellows can be significantly reduced.

EXAMPLES Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of a tuning mechanism for a high-power klystron in which the present invention is implemented.
According to the figure, a cavity resonator 31 has a tuning 33 disposed inside a resonance cavity 32 to change the tuning frequency by changing the volume of the resonance cavity, as in the conventional case.

The tuning mechanism 33 is connected to and supported by a tuning mechanism 34 located outside the cavity resonator, and is displaced within the resonant cavity 32 . Further, between the outer wall of the resonant cavity 32 and the flange portion 33A of the tuner 33, a high-power klystron including the inside of the cavity resonator is maintained in a vacuum.
A bellows 35 is provided which allows the tuner 33 to be displaced by mechanical deformation.

The tuner 33 is connected to and supported by a tuner support mechanism 60 comprising a tuner shaft 36 and a spring 38 that constantly applies a force in a direction opposite to atmospheric pressure to the tuner shaft by its restoring force.

Here, the synchronization support mechanism 60 includes the resonant cavity 32
It is connected and fixed to the outer wall of the building, for example, with screws.

Further, the distal end of the tuner shaft 36 in the direction opposite to the tuning side comes into contact with one of the plural adjustment screws 41 screwed onto the same surface of the gear 40 which can be rotated by rotating the change gear 38. There is. Here, each of the adjusting screws 41 sets the tuning 33 in the cavity resonator 1 at a specific position via the tuner shaft 36, and is screwed in advance to such an extent that the cavity resonator 31 can obtain a specific tuning frequency. has been adjusted. Therefore, the base plate 39, the gear 40, the adjusting screw 41, etc. located thereon form a preset portion.

A collar 42 is provided on the substrate 39 of the preset section 70.
A substrate 43 of the drive mechanism 80 is attached to the drive mechanism 80 by screws or the like.

A bearing 44 is provided on the board 43 of the drive mechanism.
A locking shaft 45 is rotatably mounted via A, and the locking shaft 45
is configured not to be displaced relative to the substrate 43 in its axial direction. Furthermore, a fixing plate 47 is fixed to the outer wall of the resonant cavity 2 at a fixed position via screws. A threaded portion of a locking shaft 45 is screwed into the fixed plate 47, and an unlocking plate 46 and a locking plate 53 are fixed to the locking shaft 45 on both sides of the screwed portion. Therefore, when the locking shaft 45 is rotated, the lock plate 53
Locking shaft 45 until fixing plate 47 hits
The locking shaft 45 can be displaced toward the cavity resonator (to the left in the figure), or the locking shaft 45 can be displaced in the opposite direction until the fixing plate 47 touches the unlocking plate 46.

Furthermore, a sprocket 48A is fixed to the locking shaft 45. Furthermore, a locking screw 4 is attached to the board 43 via a bearing 44B.
9 is rotatably attached. This locking screw 49 is also configured not to be displaced relative to the substrate 43 in its axial direction. Further, the locking link screw 49 also has a portion that is screwed into the fixing plate 47, and an unlocking plate 46 and a locking plate 53 are fixed to both sides of the screwing portion. Also, attach sprocket 1 to locking link screw 49.
8B is fixed. Those sprockets 48
A and its sprocket 48B have chain 5.
0 is suspended, and as the locking shaft 45 rotates, the locking screw 49 also rotates, and the fixing plate 4
The substrate 43 and, in turn, the preset portion 70 are displaceable in parallel to the preset portion 7. That is,
The preset section 70 can be moved in parallel to the tuning support mechanism 60.

To change the tuning frequency in a high-power klystron tuning mechanism having such a structure, first, the locking shaft 45 is rotated until the unlocking plate 46 touches the base plate 47 of the tuning support mechanism. At this time, the rotation of the locking shaft 45 is caused by the sprocket 48.
It is also transmitted to the locking screw 49 via the chain 50 and the sprocket 48B, and the preset part 70 moves in parallel with the base plate 43 of the synchronizing support mechanism together with the base plate 43 of the drive mechanism.
Thereafter, the change gear 38 is rotated, the gear 40 that meshes with it is rotated, and another adjustment screw set to the frequency to be changed is inserted into the tuner shaft 36.
align with the central axis of

Then, the locking shaft 45 is rotated again, this time in the opposite direction from the front, until the locking shaft 45 and the lock plate 53 of the locking screw 39 touch the base plate 47 of the synchronization support mechanism, and the adjustment screw of the preset section and the synchronization support mechanism are rotated. This can be done by connecting the tuner shaft 36 of the mechanism.

Therefore, according to the structure of the tuning mechanism according to this embodiment, the bellows of the cavity resonator changes the frequency by displacing the preset portion with respect to the tuning support mechanism connected and fixed to the outer wall of the resonant cavity. It will not expand or contract significantly when changing.

Therefore, fatigue of the metal that forms the bellows can be reduced, which eliminates the problem of leaks occurring in the bellows, breaking the vacuum seal, and rendering the high-power klystron unusable in a shorter period than its original lifespan. It disappears.

Effects of the Invention As is clear from the above explanation, according to the present invention, even if the frequency is changed frequently, the risk of leakage occurring in the bellows can be significantly reduced. Therefore, according to the present invention, it is possible to realize a tuning mechanism for a high-power klystron having a structure that can maintain the high-power klystron mechanically stable for a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of a tuning mechanism for a high-power klystron employing the present invention.
The figure is a sectional view showing the structure of a conventional tuning mechanism for a high-power klystron. Main reference numbers, 1, 31...Cavity resonator, 3,
33...Synchronization, 4,34...Synchronization mechanism, 5,3
5... Bellows, 6, 36... Tuner shaft, 10, 40... Gear, 15, 45... Locking shaft, 16A, 16B, 46A, 46B
...Unlocking plate, 19,49... Locking screw, 23A, 23B, 53A, 53B... Locking plate, 60... Tuning support mechanism, 70... Preset section, 80... Drive mechanism.

Claims (1)

[Claims for Utility Model Registration] Connected to a tuner disposed within a cavity resonator and fixed to the cavity resonator via a bellows, and always applying a constant force in the axial direction to the tuner. a synchronized support mechanism, a plurality of protrusions whose positions can be mechanically switched, and at least one of the protrusions;
a preset portion that contacts at least a portion of the tuning support mechanism to position the tuning at a desired position; and a drive mechanism that mechanically connects or disconnects the contact between the tuning support mechanism and the preset portion. In the tuning mechanism for a high power klystron, the tuning support mechanism is fixed to an outer wall of the resonant cavity, and the driving mechanism is configured to tune part or all of the preset section. A tuning mechanism for a high-power klystron, characterized by having a structure that can be displaced relative to a support mechanism.