Traveling wave tube body collector assembly structure, traveling wave tube and assembly method

Abstract

The present invention provides a traveling wave tube body collector assembly structure, a traveling wave tube and an assembly method. The structure comprises: a traveling wave tube body, including an output end cover; a collector assembly, including an inner collector, a collector porcelain tube, an outer collector and a transition ring; and at least one gasket arranged between the output end cover and the transition ring. The present invention utilizes a series of gaskets of known thickness to supplement the difference between the actual distance and the designed distance, so as to obtain a traveling wave tube in which the collector and the tube body are precisely assembled. The collector obtained by precisely controlling the distance between the collector and the tube body according to the method of the present invention is significantly improved in terms of collector recovery efficiency.

Description

Technical Field

[0001] The invention relates to the field of microwave vacuum electronic devices, and in particular to a traveling wave tube body collector assembly structure, a traveling wave tube and an assembly method. Background Art

[0002] The space traveling wave tube is mainly composed of three parts: the electron gun (including the cathode assembly), the high-frequency system and the collector. The traveling wave tube is a power amplifier, and its basic principle is to convert the electron injection energy into microwave energy through the high-frequency slow-wave system. Its basic working principle is that the electrons emitted from the cathode are accelerated in the electron gun to form an electron beam, and are injected into the high-frequency slow-wave system, maintained into a thin electron beam by the periodic magnetic focusing system, pass through the spiral line and realize the conversion of electron energy into microwave energy, so that the signal is amplified. The amplified microwave signal enters the antenna transmission system through the energy transmission coupling system. The electron beam that has handed over part of its energy finally enters the multi-stage step-down collector, and is decelerated before reaching the collector electrode, so that part of the energy can be recovered, and the remaining electron energy bombards the collector and is converted into heat energy.

[0003] The collector is an important component of the traveling wave tube, which is mainly composed of an outer collector, a collector porcelain tube, and an inner collector. Improving the electronic efficiency of the collector is an important means to improve the efficiency of the traveling wave tube. For high-power traveling wave tubes, high-efficiency collectors can not only improve the efficiency of the entire tube, but also effectively reduce the heat consumption of the collector, which is also very important for improving the reliability of the traveling wave tube. The position of the electron injection into the collector entrance, especially the position of the traveling wave tube output cavity and the first inner collector electrode, has a direct impact on the efficiency of the collector. Conventional assembly processes ensure the centering of the axis of each inner collector and the distance between the inner collectors through the assembly accuracy of the assembly mold or the accuracy of the parts themselves. However, after brazing, the inner collector of the collector, especially the position of the inner collector, deviates from the design value, thereby affecting the collector efficiency and the overall efficiency of the traveling wave tube. In addition, due to problems such as the consistency of parts and welding processes, there are differences in the axial dimensions of each electrode of the collector welding. This difference will lead to the inappropriate position of the electron injection outlet and the collector entrance, thereby affecting the overall efficiency, collector heat consumption and overall reliability of the high-power traveling wave tube. Therefore, in order to ensure the efficiency of the entire tube, it is necessary to find a method for accurately assembling the collector, especially a method for accurately assembling the output cavity and the collector of the traveling wave tube. Summary of the invention

[0004] In view of the above problems, the first technical problem to be solved by the present invention is to provide a traveling wave tube body collector assembly structure to improve the collector recovery efficiency.

[0005] The second technical problem to be solved by the present invention is to provide a traveling wave tube including the collector assembly structure as described above.

[0006] The third technical problem to be solved by the present invention is to provide a traveling wave tube collector assembly method, thereby improving the accuracy of the traveling wave tube output cavity and the collector, and thus improving the collector recovery efficiency.

[0007] In order to solve the above-mentioned first technical problem, the present invention adopts the following technical solution:

[0008] A traveling wave tube body collector assembly structure, the structure comprising:

[0009] The traveling wave tube body includes an output end cover;

[0010] The collector assembly comprises an inner collector, a collector porcelain tube, an outer collector and a transition ring; and at least one gasket arranged between the output end cover and the transition ring.

[0011] Preferably, the material of the gasket is the same as the material of the output end cover or the material of the transition ring.

[0012] Preferably, a concave platform structure is formed on the edge of the output end cover.

[0013] Preferably, the gasket is selected from a plurality of gasket groups with different thicknesses, and the gasket thickness of each gasket group is selected from 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm or 0.5 mm.

[0014] Preferably, the thickness of the gasket is selected from 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm or 0.5 mm.

[0015] In order to solve the above second technical problem, the present invention adopts the following technical solution:

[0016] A traveling wave tube comprises the traveling wave tube body collector assembly structure as described above.

[0017] To solve the third technical problem mentioned above, the present invention adopts the following technical solution:

[0018] A method for assembling a collector of a traveling wave tube, comprising the traveling wave tube as described above, the method comprising:

[0019] By thinning the edge of the output end cover of the tube body by a predetermined thickness, the depth of the concave platform structure of the output end cover is increased;

[0020] Measuring the distance between the electron injection port of the inner collector and the transition ring in the collector assembly;

[0021] Assemble the traveling wave tube body and collector,

[0022] A gasket is added between the output end cover of the tube body and the collector transition ring so that the distance between the electron injection port of the inner collector and the electron injection port of the tube body meets the design requirements.

[0023] Preferably, the method for obtaining the predetermined thickness comprises:

[0024] Assemble and braze multiple collector assemblies,

[0025] Measure the distance between the inner collector electron injection port and the transition ring in each collector assembly.

[0026] The difference between each measured distance and the designed dimension of the distance between the inner collector electron injection port and the transition ring in the collector assembly is calculated, and the maximum value of the calculated difference is used as the predetermined thickness.

[0027] Preferably, the method further comprises welding the assembled traveling wave tube body, gasket and collector together by argon arc welding.

[0028] Preferably, the gasket is selected from a plurality of gasket groups with different thicknesses, and the gasket thickness of each gasket group is selected from 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm or 0.5 mm.

[0029] The beneficial effects of the present invention are as follows:

[0030] The present invention increases the depth of the concave platform structure that matches the output end cover of the tube body with the collector transition ring from the design height to the sum of the design height and the predicted maximum matching error, so that it is possible to accurately adjust the distance between the collector electron injection port and the tube body electron injection port by increasing the thickness of the gasket during the assembly of the entire tube. By actually measuring the distance between the collector electron injection port and the transition ring surface in the brazed collector assembly, and using a series of gaskets of known thickness to supplement the difference between the actual distance and the design distance, a traveling wave tube in which the collector and the tube body are accurately assembled can be obtained. The collector obtained by accurately controlling the distance between the collector and the tube body according to the method of the present invention is significantly improved in terms of collector recovery efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings:

[0032] Figure 1a as well as Figure 1b A schematic diagram of the assembly structure of a traveling wave tube body and a collector in the prior art is shown.

[0033] Figure 2a as well as Figure 2b Shown is a flow chart of the preparation of the traveling wave tube collector assembly structure according to the present invention.

[0034] Figure 3a A schematic structural diagram of the output end cover of the tube body of the present invention is shown.

[0035] Figure 3b Show Figure 3a Enlarged schematic diagram of part A in the middle.

[0036] Figure 4a A schematic diagram of the assembly structure of a traveling wave tube collector according to an embodiment of the present invention is shown.

[0037] Figure 4b Show Figure 4a Enlarged schematic diagram of part I in the middle.

[0038] Figure 5a A schematic diagram of the assembly structure of a traveling wave tube body collector according to another embodiment of the present invention is shown.

[0039] Figure 5b Show Figure 5a Enlarged schematic diagram of part II.

[0040] Figure 6 A simulation diagram showing the design value of the recovery efficiency of the collector structure provided by the present invention.

[0041] Figure 7 A simulation diagram showing the recovery efficiency of the collector structure provided by Example 1 of the present invention is shown.

[0042] Figure 8 A simulation diagram showing the recovery efficiency of the collector structure provided by Example 2 of the present invention. DETAILED DESCRIPTION

[0043] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred embodiments and accompanying drawings. Similar components in the accompanying drawings are represented by the same reference numerals. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0044] Figure 1a as well as Figure 1b The schematic diagram of the assembly structure of the traveling wave tube body and the collector of the prior art is shown. As shown in the figure, the assembly structure 100 includes a traveling wave tube body 110 and a collector assembly 120. The collector assembly 120 includes, for example, a first inner collector 121, a collector ceramic tube 122, an outer collector 123 and a collector transition ring 124, wherein the collector ceramic tube 122 is fixed between the first inner collector 121 and the outer collector 123, and the traveling wave tube body 110 is welded together at the output cavity side through an output end cover 111.

[0045] like Figure 1a as well as Figure 1bAs shown, the collector assembly includes a first inner collector. Those skilled in the art will appreciate that the collector assembly may include multiple inner collectors as needed. For example, the collector assembly may include a second inner collector and a third inner collector in addition to the first inner collector, forming a multi-stage step-down collector structure. The present invention does not limit this. In the present invention, the output end cap and the collector assembly have a coaxially arranged central hole for electron injection from the high-frequency slow-wave structure to the collector.

[0046] The output end cover has a concave platform 112 on one side of the collector, which is concave toward the collector. The depth D and diameter of the concave platform match the thickness h and inner diameter of the collector transition ring respectively. Figure 1a as well as Figure 1b In the conventional traveling wave tube shown, the design size of the end of the first inner collector facing the tube body is from the electron injection port of the tube body. When assembling the collector assembly, the distance L1 between the end of the first inner collector facing the tube body and the collector transition ring is controlled by means of a mold. After the collector assembly is obtained by brazing, the axial assembly size of the output end cover and the transition ring is controlled and welded to achieve the fixation of the tube body and the collector assembly. The traveling wave tube obtained in this way was found through analysis that due to factors such as the tolerance size of the parts, the amount of solder added, and the different solder dispersion degrees of the brazing process, the distance between the first inner collector and the transition ring surface in the collector assembly has an error compared with the design size. Taking a certain frequency band space traveling wave tube as an example, there is a deviation of ±0.5mm at this position of the collector assembly, which will affect the collector recovery efficiency by 1-2%, as shown in the comparative example of Figure 5.

[0047] To solve the above problems, the embodiments of the present invention provide a structure and method for accurately controlling the critical dimensions of the collector. First, the method comprises:

[0048] Step S1, predicting the error of the assembly dimension of the collector assembly.

[0049] According to the conventional structure, several, for example, 3-5 collector assembly test pieces 120 are pre-assembled and brazed. Figure 2a as well as Figure 2b As shown. The measured distance L1' between the end of the first inner collector facing the tube body and the surface of the collector transition ring of each test piece is measured. The measured distance L1' is compared with the designed distance L1 between the first inner collector and the collector transition ring, and the predicted assembly error δ = L1'-L1 of each collector assembly is calculated to obtain the predicted error set [δ1, δ2], where δ1 is the minimum predicted error and δ2 is the maximum predicted error.

[0050] Step S2, increasing the depth of the concave platform structure of the output end cover of the tube body according to the predicted assembly error.

[0051] Figure 3aA schematic diagram showing the output end cover 111 of the tube body is shown. Figure 3b Show Figure 3a The enlarged schematic diagram of the middle A part. The end cap has a concave platform structure 112 on the side facing the collector assembly. The end cap with the concave platform structure matches the transition ring of the collector assembly to weld the tube body and the collector assembly together. It can be understood that the end cap can also match the structure of the transition ring and be designed to have a boss structure on the side facing the collector assembly, or have a planar structure. The present invention is not limited to this. The following is an explanation with reference to the accompanying drawings, taking the end cap with a concave platform structure as an example.

[0052] The original design concave platform depth of the concave platform 112 of the tube output end cap is D. According to the predicted assembly error obtained in step 1, by thinning the thickness of the end cap edge, that is, increasing the depth of the concave platform, the depth of the concave platform structure matching the end cap and the collector assembly transition ring is adjusted to D+δ2. To describe it in another way, without changing the overall thickness of the end cap, by thinning the thickness of the end cap edge, the depth of the concave platform step is increased to the sum of the design size D and the maximum predicted assembly error δ2.

[0053] Step S3, assembling and brazing the collector assembly. The distance between the first inner collector electron injection port in the collector assembly and the collector transition ring is measured to determine the compensation height.

[0054] The collector assembly is assembled by using a mold and brazed to obtain a brazed collector assembly 120. For each collector assembly, the distance L1' between the electron injection port end of the first inner collector facing the tube body side and the surface of the collector transition ring is measured, and the measured error δ between the measured distance L1' and the design dimension L1 is calculated. According to the predicted error δ2 and the measured error δ, the transition ring compensation height of the transition ring of the collector assembly is determined.

[0055] Step S4, assembling the tube body, the output end cover and the collector assembly, and setting a gasket between the output end cover and the collector transition ring so that the distance between the electron injection output port of the tube body and the electron injection input port of the collector meets the design requirements.

[0056] The tube body, the output end cap and the collector assembly are assembled by using a mold. A gasket with a thickness of δ2-δ is set above the collector transition ring. The material of the gasket can be the same as the material of the transition ring or the material of the end cap, and the inner diameter and outer diameter of the gasket are set corresponding to the inner and outer diameters of the transition ring. The gasket is a plurality of groups of gaskets with thicknesses of 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, and 0.5mm, so that the combination of gaskets of different thicknesses can meet the requirements of compensation height.

[0057] Step S4, welding the assembled structure to obtain a tube collector assembly structure with precisely controlled dimensions.

[0058] Figure 4a The tube collector assembly structure 400 according to Example 1 of the present invention is shown. Figure 4b As shown, the tube body collector assembly structure 400 includes a traveling wave tube body 410, a collector assembly 420 and a plurality of gaskets 430 arranged between the tube body and the collector assembly. The collector assembly 220 includes a first inner collector 421, a collector porcelain tube 422, an outer collector 423 and a collector transition ring 424. The traveling wave tube body includes an output end cover 411, which has a concave or convex structure that cooperates with the collector assembly transition ring, and a through hole for electron injection is arranged at the center. The plurality of gaskets are arranged between the edge of the output end cover (i.e., the bottom surface of the concave structure) and the transition ring, and the thickness of the gaskets makes the distance between the end of the first collector facing the tube body and the electron injection outlet of the tube body meet the design requirements.

[0059] Example 1

[0060] According to the tube collector assembly structure of Example 1, Figure 4a As shown. In Example 1, the original concave platform structure depth D of the output end cover 411 concave platform structure design is 0.5mm, and the adjusted dimension δ2 is 0.15mm; the measured distance L1' of the first inner collector transition ring is 1.45mm, and the designed distance L1 is 1.55mm, δ = (L1'-L1) = 0.1mm, and a gasket with a thickness of δ2-δ is set above the collector transition ring. The gasket thickness is 0.15-(-0.1) = 0.25mm, which is a combination of 1 gasket with a thickness of 0.05mm and 2 gaskets with a thickness of 0.1mm. The assembly error and the design dimension are 0. The collector recovery efficiency of the collector assembly structure obtained in this example is 74.10%, referring to Figure 6 and Figure 7 shown.

[0061] Example 2

[0062] According to the tube collector assembly structure of Example 1, Figure 4a In Example 2, combined Figure 5a as well as Figure 5b As shown, the original concave platform structure depth D of the concave platform structure design of the output end cover 411 is 0.5mm, and the adjusted dimension δ2 is 0.15mm; the measured distance L1' of the first inner collector to the transition ring is 1.6mm, and the designed distance L1 is 1.55mm, δ = (L1'-L1) = 0.05mm, and a gasket with a thickness of δ2-δ is set above the collector transition ring, and the gasket thickness is 0.15+0.05=0.1mm, which is a gasket with a thickness of 0.1mm, and the assembly error and the designed dimension are 0. The collector recovery efficiency of the collector assembly structure obtained in this example is 74.10%, referring to Figure 6 and Figure 8 shown.

[0063] Comparative Example 1

[0064] As shown in the tube collector assembly structure of Example 1. In Comparative Example 1, the original concave platform structure depth D of the output end cover concave platform structure design is 0.5 mm, and the measured distance L1 between the first inner collector and the transition ring in the collector assembly is 1.45 mm. The collector recovery efficiency of the collector assembly structure obtained in Comparative Example 1 is 72.96%.

[0065] Comparative Example 2

[0066] As shown in the tube collector assembly structure of Example 2. In Comparative Example 2, the original concave platform structure depth D of the output end cover concave platform structure design is 0.5, and the measured distance L1 between the first inner collector and the transition ring in the collector assembly is 1.6. The collector recovery efficiency of the collector assembly structure obtained in Comparative Example 1 is 73.37%.

[0067] According to the method of the present invention, by increasing the depth of the concave platform structure that matches the output end cap of the tube body with the collector transition ring from the designed height to the sum of the designed height and the predicted maximum matching error, it is possible to precisely adjust the distance between the electron injection port of the collector and the electron injection port of the tube body by increasing the thickness of the gasket during assembly of the entire tube. By actually measuring the distance between the electron injection port of the collector and the surface of the transition ring in the brazed collector assembly, and using a series of gaskets of known thickness to supplement the difference between the actual distance and the designed distance, a traveling wave tube with the collector and the tube body precisely assembled can be obtained. Figures 6 to 8 As shown, according to Example 1 and Example 2 of the present invention, the designed recovery efficiency is 74.10%. The recovery efficiencies of Comparative Example 1 and Comparative Example 2 are 72.96% and 73.37% respectively, and the errors between the two are 1.14 and 0.73 percentage points. It can be seen that under the condition of the same design parameters, the collector recovery efficiency of Example 1 and Example 2 obtained by accurately controlling the distance between the collector and the tube body according to the method of the present invention is significantly improved.

[0068] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A method for assembling a traveling wave tube collector assembly structure, characterized in that: The traveling wave tube body collector assembly structure comprises: The traveling wave tube body includes an output end cover; A collector assembly, comprising an inner collector, a collector porcelain tube, an outer collector and a transition ring; and at least one gasket disposed between the output end cover and the transition ring; The assembly method comprises: By thinning the edge of the output end cover of the tube body by a predetermined thickness, the depth of the concave platform structure of the output end cover is increased; Measuring the distance between the electron injection port of the inner collector and the transition ring in the collector assembly; Assemble the traveling wave tube body and collector, A gasket is added between the output end cover of the tube body and the collector transition ring so that the distance between the electron injection port of the inner collector and the electron injection port of the tube body meets the design requirements.

2. The assembly method according to claim 1, characterized in that: The material of the gasket is the same as that of the output end cover or the transition ring.

3. The assembly method according to claim 1, characterized in that: The edge of the output end cover is formed with a concave platform structure.

4. The assembly method according to claim 1, characterized in that: The gasket is selected from a plurality of gasket groups with different thicknesses, and the gasket thickness of each gasket group is selected from 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm or 0.5 mm.

5. The assembly method according to claim 1, characterized in that: The thickness of the gasket is selected from 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm or 0.5mm.

6. The assembly method according to claim 1, characterized in that: The method for obtaining the predetermined thickness includes: Assemble and braze multiple collector assemblies, Measure the distance between the inner collector electron injection port and the transition ring in each collector assembly. The difference between each measured distance and the designed dimension of the distance between the inner collector electron injection port and the transition ring in the collector assembly is calculated, and the maximum value of the calculated difference is used as the predetermined thickness.

7. The assembly method according to claim 1, characterized in that: The method further comprises welding the assembled traveling wave tube body, gasket and collector together by argon arc welding.

8. A traveling wave tube, comprising a traveling wave tube body collector assembly structure obtained according to the assembly method of claim 1.

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