JP3067699B2 - Radiation cooled traveling wave tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation structure for a collector portion of a traveling wave tube which is a microwave tube, and more particularly to a radiation cooling type collector radiator for a high output satellite traveling wave tube.

[0002]

2. Description of the Related Art FIG. 5 shows an example of a radiation cooling type traveling wave tube which has been used relatively frequently. As shown in FIG. 5, the traveling wave tube is roughly composed of three parts: an electron gun 28, a high frequency circuit 29, and a collector 30.

[0003] In the traveling wave tube shown in FIG.
8, an electron beam (not shown) is formed, and while the electron beam passes through the high-frequency circuit 29, the high-frequency wave introduced from the input line 15 interacts with the electron beam to amplify the high-frequency wave.

[0004] The amplified high frequency is taken out from the output line 11, and the electron beam after the interaction is captured by the collector 30.

In order to prevent the diffusion of the electron beam due to the mutual repulsive force of the electrons, the electron beam is narrowed down by an alternating magnetic field generated by a periodic magnetic field focusing device in which annular macnets 13 and pole pieces 12 are alternately combined.

In the electron gun section 28, a cathode 23 for extracting an electron beam is heated to about 1000 ° C. by a heater 24. A voltage of several KV is applied between the cathode 23 and the anode electrode 21, and the electron beam is accelerated and extracted from the cathode 23 by this potential difference. Reference numeral 22 denotes a Wehnelt electrode for narrowing electrons emitted from the cathode 23 into a thin electron beam. Reference numeral 25 denotes an exhaust pipe, and the inside of the traveling wave tube passes through the exhaust pipe 25 during the manufacturing process to 10 ^-9.
It is evacuated to a high vacuum of about torr, and then exhaust pipe 25
Are pressed and sealed.

The high-frequency circuit 29 has a high-frequency input window 16 and an output window 10 and a spiral helix 17 communicating between the input window 16 and the output window 10. Helix 17 is connected to input line 15 and output line 11. The electron beam emitted from the electron gun 28 passes through the inside of the helix 17 and interacts with the high frequency wave transmitted to the helix 17 through the input line 15 during the passage. Then, the kinetic energy of the electron beam is used for amplifying the high frequency, and the amplified high frequency is extracted from the output line 11. The electron beam after the interaction is
The beam is captured by the collector unit 30.

The collector section 30 shown in FIG. 5 has a four-stage potential decreasing type collector structure. That is, electrons having various velocities are included in the spent beam, and the heat generated by the collision of the electron beams with the collector electrodes 4, 5, 6, and 7 is reduced as much as possible. Is applied to the collector electrodes 4, 5, 6, and 7, so that the electrons softly land on the collector electrodes 4, 5, 6, and 7.

Therefore, it is preferable that the collector electrodes 4, 5, 6, 7 are innumerable. However, in consideration of the simplicity of the collector structure, a collector electrode structure having two to four stages is generally employed. Higher voltages are applied to the collector electrodes 4, 5, 6, and 7 in order from the electrode closer to the electron gun. Each collector electrode 4, 5, 6, 7 is insulated by a collector insulating stone 9. The heat generated at the collector electrodes 4, 5, 6, 7 is transmitted to the collector can 19 via the collector insulating stone 9. From the collector can 19, heat is radiated to outer space by radiation. The surface of the collector can 19 is subjected to a surface treatment so that the thermal emissivity becomes 0.8 or more. When the heat generated in the collector section 30 is transmitted to the high-frequency circuit 29, the temperature of the high-frequency circuit 29 rises and the beam transmission may become unstable. Not to be transmitted to
Is connected to the collector support plate 3 via a bellows 18a and a plurality of thin metal cylinders 18b.

Such a conventional radiation-cooled traveling wave tube P having a collector structure is used for a high-output traveling wave tube having a power of 130 W to 200 W or more for a satellite.
As shown in Fig. 1, it is mounted on a satellite G launched into outer space, and its number is limited to a few. However, in order to reduce the heat load of the satellite G, a slight increase in weight is required. It was used at the cost of sacrifice. By the way, FIG.
The weight of the traveling-wave tube having the collector structure shown in FIG.

However, in recent years, satellites have been increasing in size and capacity, and as shown in FIG. 12, the number of traveling wave tubes P mounted on one satellite G has been increased from 20 to 30, and the output is 100 W.
Even though the output is relatively low before and after, the number of mounted units is large and the thermal load on the satellite G is increased, and a new lightweight radiation-cooled traveling wave tube is required.

[0012]

In response to such technical requirements, a traveling wave tube having a new collector radiator shape as shown in FIG. 6 or 8, for example, has been developed.

FIG. 6 is a perspective view showing a collector portion of a radiation cooling type traveling wave tube using a collector radiator called a fin type, and FIG. 7 is a sectional view of the collector portion. Although the sectional shape of the collector section 30 is not shown in the drawing, a collector structure as shown in FIG. 2 is assumed, for example. In such a structure of the collector radiator, heat is radiated in the radial direction from the radial blade plate 26 in contact with the heat reflection plate 2.

FIG. 8 is a perspective view showing a collector portion of a radiation cooling type traveling wave tube using a collector radiator called a cone type, and FIG. 9 is a sectional view thereof. In such a shape of the collector radiator, the heat from the collector portion 30 is more radiated in the axial direction than in the radial direction of the cone-shaped radiator plate 27.

In these conventional light-weighted radiation-cooled traveling wave tubes, the envelope of a conduction-cooled collector that dissipates heat generated in the collector to the case substrate of the traveling wave tube by conduction is used as it is. It is characterized in that a collector radiator is inserted in close contact with the outer peripheral surface of the collector. With such a configuration, weight reduction is realized, and the weight of the traveling wave tube is about 1 kg.

[0016] However, in such a conventional example having a reduced weight, there is a problem in the shape of each radiator.

For example, in the fin type configuration shown in FIG. 6, when a plurality of traveling wave tubes are installed side by side on a satellite, thermal interference occurs between the adjacent traveling wave tubes and the temperature of the collector section increases. Has an adverse effect of rising. In addition, heat dissipation in the axial direction is very small, so that there is a disadvantage that heat dissipation efficiency is low.

On the other hand, in the shape shown in FIG. 8, heat radiation in the radial direction is small, and only heat radiation in the axial direction is used. Therefore, heat radiation efficiency is low. The diameter of the cone-shaped heat radiating plate for increasing the heat radiating area must be increased, and there is a problem that the weight increases and a problem occurs in mechanical strength.

An object of the present invention is to improve the disadvantages of the prior art, realize balanced heat dissipation, increase the heat dissipation efficiency, and provide a lightweight radiant cooling type with mechanical strength for use on a satellite. To provide a wave tube.

[0020]

In order to achieve the above object, a radiant cooling type traveling wave tube according to the present invention is a radiant cooling type traveling wave tube having a collector radiator.
The body transfers the heat generated in the collector of the traveling wave tube to outer space.
Heat is radiated by the radiant cooling method.
The inner tube has a double inner and outer structure with the outer tube.
It is obtained by close contact with the outer peripheral surface of the collector portion of the traveling wave tube, before
The dome-shaped outer tube is formed by folding one end of the inner tube to the front.
A double pipe is constructed for the inner pipe .

[0021]

The dome-shaped outer tube is formed in a tapered shape.

The open end of the dome-shaped outer tube is joined to the heat reflecting plate of the collector.

The open end of the dome-shaped outer tube is joined at several points in the circumferential direction of the heat reflecting plate of the collector.

In the dome-shaped outer tube, the folded portion is joined to the heat reflecting plate of the collector portion, and an open end thereof is opened to the outside.

[0026]

According to the radiation cooling type traveling wave tube according to the present invention, the collector radiator for radiating the heat generated in the collector portion of the traveling wave tube to outer space by the radiation cooling method has an inner / outer double structure. Expand the heat radiation area to a three-dimensional space.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a perspective view showing a radiation-cooled traveling wave tube according to Embodiment 1 of the present invention, and FIG. 2 is a sectional view thereof.

In the drawing, the radiation-cooled traveling wave tube according to the present invention is basically intended for a radiation-cooled traveling wave tube having a collector radiator 1. The collector radiator 1 radiates heat generated in the collector portion 30 of the traveling-wave tube to the outer space by a radiation cooling method. The radiator area is expanded to a three-dimensional space by adopting an inner / outer double structure. is there.

Next, a specific example of the radiation-cooled traveling wave tube according to the present invention will be described as a first embodiment with reference to FIGS. In the figure, 10 is an output window, 11 is an output line, 12 is a pole piece, 13 is a magnet, and 14 is a case plate. The collector portion 30 of the traveling wave tube is composed of collector electrodes 4, 5, 6, 7;
And

The collector radiator 1 in the radiant cooling type traveling wave tube according to the first embodiment of the present invention is a tubular structure made of a lightweight and high thermal conductivity material, and is generated in the collector portion 30 of the traveling wave tube. The radiating heat is radiated to the outer space by a radiation cooling method, and has an inner / outer double structure of an inner tube 1A and a dome-shaped outer tube 1B. The inner tube 1A is in close contact with the outer peripheral surface of the collector portion 30 of the traveling wave tube, and the dome-shaped outer tube 1B is configured such that one end of the inner tube 1A is folded to form a double tube with respect to the inner tube 1A. It is.

The dome-shaped outer tube 1B is formed in a tapered shape, and a notch 1C is formed at an opening edge thereof, and the opening end of the dome-shaped outer tube is connected to the heat reflecting plate 2 of the collector 30. Are joined at several places in the circumferential direction. In the first embodiment, the dome-shaped outer tube 1B is formed in a tapered shape of about 20 °.

Dome-shaped outer tube 1 in contact with heat reflecting plate 2
A plurality of notches 1C are provided at the open end of B, and are brazed to the heat reflecting plate 2 at a plurality of positions on the circumference. Is connected with the minimum brazing area so that it does not flow into The outer surface of the dome-shaped outer tube 1B is subjected to a surface treatment such as ceramic coating in order to increase the heat radiation rate. Other configurations are the same as the conventional one.

According to the first embodiment shown in FIGS. 1 and 2,
Because the dome-shaped outer tube 1B is tapered,
The heat can be radiated with good balance in the axial direction, and the heat radiation efficiency can be increased. Further, since the end face of the outer tube 1B is fixed to the heat reflection plate 2 by brazing, the mechanical strength can be increased.

(Embodiment 2) Next, Embodiment 2 of the present invention
Will be described with reference to FIGS. 3 and 4. In Embodiment 2 shown in FIG. 3, the dome-shaped outer tube 1B of the collector radiator 1 is inserted around the outer periphery of the collector 30 in a direction opposite to the shape described in FIG. Board 2
And the open end thereof is opened to the outside.

According to the second embodiment of the present invention, heat is radiated from the dome-shaped outer tube 1B not only from the outer surface but also from the inner surface by radiation, so that the heat radiation efficiency can be further improved. Further, in order to secure the mechanical strength of the dome-shaped outer tube 1B, brazing may be performed at several places of the folded portion 1D of the dome-shaped outer tube 1B in contact with the heat reflecting plate 2.

In any of the embodiments, the heat reflecting plate 2 has a role of preventing heat generated in the collector radiator 1 from being transmitted to the body side of the traveling wave tube by radiation.
In addition, when a traveling wave tube is installed side by side (see FIG. 12)
Since the side surface of the collector radiator 1 is cylindrical, the thermal interference between adjacent traveling wave tubes can be greatly improved as compared with the case of a fin-type collector radiator.

[0038]

As described above, according to the present invention, it is possible to provide a collector radiator that can be significantly reduced in weight, can improve the efficiency of heat dissipation, and has enhanced mechanical strength.

The collector radiator of the present invention has a simpler shape than that of the conventional shape, and can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is a perspective view showing Embodiment 2 of the present invention.

FIG. 4 is a sectional view of the same.

FIG. 5 is a cross-sectional view showing an example of a traveling wave tube incorporating a radiation cooling type collector in a conventional example.

FIG. 6 is a perspective view showing an example of a conventional radiation cooling collector whose weight is reduced.

FIG. 7 is a sectional view of the same.

FIG. 8 is a perspective view showing another example of a conventional radiation cooling collector whose weight is reduced.

FIG. 9 is a sectional view of the same.

FIG. 10 is a diagram showing a technique disclosed in Japanese Patent Application Laid-Open No. 6-323665.

FIG. 11 is a perspective view showing a conventional satellite structure equipped with a radiation cooling traveling wave tube.

FIG. 12 is a perspective view showing a state-of-the-art satellite structure equipped with a large number of radiation-cooled traveling wave tubes.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Collector radiator 1A Inner tube 1B Domed outer tube 2 Heat reflection plate 3 Collector support plate 4, 5, 6, 7 Collector electrode 30 Collector part

Claims (5)

(57) [Claims] 1. A radiation cooling type traveling wave tube having a collector radiator, wherein the collector radiator radiates heat generated in a collector portion of the traveling wave tube to outer space by a radiation cooling method, The inner tube has an inner / outer double structure of an inner tube and a dome-shaped outer tube. The inner tube is in close contact with the outer peripheral surface of the collector portion of the traveling wave tube, and the dome-shaped outer tube has one end of the inner tube. A radiation-cooled traveling-wave tube, which is folded back to form a double tube with respect to the inner tube. 2. The radiant cooling type traveling wave tube according to claim 1 , wherein said dome-shaped outer tube is formed in a tapered shape. Wherein the open end of the dome-shaped outer tube, radiation cooling type traveling-wave tube according to claim 1 or 2, characterized in that joined to the heat reflecting plate of the collector portion. 4. The radiant cooling type progression according to claim 3 , wherein the open end of the dome-shaped outer tube is joined at several places in the circumferential direction of the heat reflecting plate of the collector portion. Wave tube. 5. The dome-shaped outer tube, wherein the folded portion is joined to a heat reflecting plate of the collector portion, and an open end thereof is open to the outside.
3. The radiation cooled traveling wave tube according to 1 or 2 .