Depressurization collector applied to relativistic backward wave tube

Abstract

The invention provides a step-down collector applied to a relativistic backward wave tube, which is characterized in that the center axis of the step-down collector is the same as that of the relativistic backward wave tube, the inner diameter of the input end of the collector is the same as that of the backward wave tube body, and the inner diameter of the output end of the collector is the same as that of the output part of the backward wave tube; the radius at the inlet of the collector electrode is gradually changed, and the collector electrode is insulated from the backward wave tube body and the backward wave tube output part through an insulating ceramic piece. After the step-down collector is adopted, electric energy is recycled, the total efficiency of the device is improved, the heating loss is reduced, and the heat dissipation pressure is reduced; the relativistic backward wave tube system reduces the hardness and dosage of generated X-rays, the lead plate is included, the X-rays are reduced and relieved from the source, the lead sheet blocks the X-rays, and therefore the X-rays diverging to the outside of the relativistic backward wave tube system are greatly reduced, and testing environment safety is better facilitated.

Description

Technical Field

[0001] This invention relates to a relativistic backward-wave oscillator (RBWO), belonging to the field of high-power microwave technology. Background Technology

[0002] In the field of high-power microwaves, the relativistic backward wave tube (RWT) is one of the most commonly used high-power microwave sources. The voltage of the power supply driving the RWT is generally above 100kV, reaching hundreds ofkV, or even megakV. Figure 2 It has the structure of a conventional relativistic backward wave tube. The collector electrode is directly connected to the slow-wave structure, so their potentials are naturally the same. The energy distribution of the electron beam after "interacting" through the slow-wave structure (i.e., the interaction region) is as follows: Figure 3 As shown, the electron beam still possesses very high energy; generally, the absolute value of Vmin is greater than half the absolute value of the cathode voltage. In a conventional RBWO, these electrons reach the collector, generating significant heat, especially in high-repetition-rate (PRR) operation mode where multiple pulses of electron beams strike the collector. The high-energy electrons also generate X-rays when they collide with the metal collector. While older Tesla drive power supplies typically produced only one voltage, technological advancements and the application of new high-voltage drive power supplies make it easy to provide power leads with different voltages. This significantly facilitates the use of a step-down collector in RBWOs. Summary of the Invention

[0003] To reduce the heat generated at the collector of an RBWO and alleviate the heat dissipation pressure, the present invention aims to provide a step-down collector for RBWO applications. The specific technical solution is as follows:

[0004] A step-down collector electrode for use in a relativistic backward wave tube includes: the step-down collector electrode is the same as the central axis of the relativistic backward wave tube; the inner diameter of the input end of the collector electrode is the same as the inner diameter of the backward wave tube body; the inner diameter of the output end of the collector electrode is the same as the inner diameter of the output portion of the backward wave tube; the radius gradually changes at the inlet of the collector electrode; and the collector electrode is insulated from the backward wave tube body and the output portion of the backward wave tube by an insulating ceramic component.

[0005] Furthermore, the collecting electrode is inserted into the backwave tube body and the output section of the backwave tube, and then connected through a vacuum with a double L-shaped cross-section via an insulating ceramic component.

[0006] Furthermore, the insulating ceramic component is connected to the radial circular wall of the collecting electrode through a metal sealing layer, which consists of a coating layer applied to the surface of the circular ceramic ring and an electroplated layer covering the surface of the coating layer.

[0007] Furthermore, within the double "L" space connecting the collecting electrode to the backwave tube body and the backwave tube output section, the outer diameter of the collecting electrode port is rounded.

[0008] Furthermore, the additional magnetic system of the backwave tube body adjusts its field value based on simulation results, so that the electron beam reaches the lead plate of the collecting electrode directly in front of the center.

[0009] Furthermore, the collecting electrode is wrapped with a lead sheet and secured by two or more lead sheet fixing rings.

[0010] Furthermore, the argon arc welded edge of the step-down collecting electrode is connected to the thin metal edge of the backwave tube body or the output section of the backwave tube in two ways: one is by argon arc welding, and the other is by fixing it to the radial circular wall of the backwave tube body or the output section of the backwave tube using O-rings and bolts.

[0011] Furthermore, the material of the coating layer is one or more of molybdenum, manganese, and silicon dioxide, and the material of the electroplating layer is nickel.

[0012] Furthermore, the collecting electrode has a cylindrical structure, with radial circular walls near both ends. The outer side of the radial circular walls is connected to the insulating ceramic component through a metal sealing layer. The cylindrical structure of the collecting electrode is divided into two parts: a cylindrical part serving as the output end and a conical part serving as the input end. The thickness of the circumferential wall at one end of the cylindrical collecting electrode is greater than the thickness of the circumferential wall at one end of the conical collecting electrode.

[0013] Furthermore, the lead sheet is located on the outer surface of the collecting electrode between the two radial circular walls, and the fixing ring is fixed to the outer surface of the lead sheet.

[0014] The present invention has the following beneficial effects:

[0015] (1) Improved the overall efficiency of RBWO.

[0016] (2) The heat generated by RBWO is reduced, which reduces the heat dissipation pressure of the heat dissipation system.

[0017] (3) By adopting a pressure-reducing collecting electrode, the hardness and dose of X-rays generated are reduced. In addition, the present invention contains lead plates, which not only reduces (in terms of dose) and lessens (in terms of X-ray hardness) X-rays at the source, but also the lead sheet blocks X-rays, thereby greatly reducing the X-rays that are emitted outside the relativistic backwave tube system, which is more conducive to environmental safety.

[0018] (4) This improves the reliability of the relativistic backwave tube system. Attached Figure Description

[0019] Figure 1This is a cross-sectional view of the entire backwave tube containing the step-down collector electrode;

[0020] Figure 2 This is a relativistic backward wave tube structure in the existing technology;

[0021] Figure 3 This is a graph showing the energy distribution density of electrons entering the collector electrode in the existing technology.

[0022] Figure 4 This is a schematic diagram of the structure of the step-down collector.

[0023] Figure 5 A diagram of a specific part of the backwave tube for applying a step-down collector.

[0024] Figure 6 This is a schematic diagram of the calculation results;

[0025] Figure 7 Another implementation of a backwave tube using a step-down collector;

[0026] Figure 8 This is a schematic diagram of the lead wires for another embodiment of the backwave tube using a step-down collector. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other. To achieve the above objectives, this invention adopts the following technical solution.

[0028] This invention provides a step-down collector electrode for use in relativistic backward wave tubes, such as... Figure 4 As shown, the voltage-reducing collecting electrode includes a collecting electrode 1, an insulating ceramic component 2, an argon arc welded edge 3 for connection, a lead sheet 4 for blocking X-rays, and a fixing ring 5 for fixing the lead sheet. The collecting electrode 1 is made of metal, and the insulating ceramic component 2 is connected to the argon arc welded edge 3 via a metal sealing layer. The collecting electrode 1 has a cylindrical structure with protruding radial circular walls near both ends. The outer side of the radial circular walls is connected to the insulating ceramic component 2 via a metal sealing layer. The cylindrical structure of the collecting electrode 1 is divided into two parts: a cylindrical part serving as the output end and a conical part serving as the input end. The thickness of the circumferential wall at one end of the cylindrical part of the collecting electrode 1 is greater than the thickness of the circumferential wall at one end of the conical part. The lead sheet 4 is located on the outer surface of the collecting electrode 1 between the two radial circular walls, and the fixing ring 5 is fixed to the outer surface of the lead sheet 4.

[0029] Figure 1 This is a cross-sectional view of the step-down collector electrode operating in the entire tube of the backwave tube. The tube body 6 of the backwave tube is connected to one end of the conical cylinder of the collector electrode 1. The magnetic field system 8 of the backwave tube surrounds the tube body 6. The additional magnetic system 8 of the backwave tube is located outside the magnetic field system 7 of the backwave tube. The output part 9 of the backwave tube is connected to one end of the cylindrical cylinder of the collector electrode 1, and its interior is a vacuum 10.

[0030] In practical operation of a relativistic backward wave tube, the collecting electrode 1 is connected to a voltage approximately half that of the cathode. The specific value is determined based on the different RBWO electron interaction efficiencies. The radial circular wall of the collecting electrode 1 has a terminal post. The lead sheet thickness is greater than 10 mm. Figure 4 The lead sheet 4 shown is fixed by the retaining ring 5. The return wave tube body 6 and the output section 9 are grounded.

[0031] The collector electrode is aligned with the central axis of the RBWO. The inner diameter of the input end of the collector electrode 1 is the same as the inner diameter of the reflector tube body 6, and the inner diameter of the output end of the collector electrode 1 is the same as the inner diameter of the reflector tube output section 9. The radius gradually changes at the inlet of the collector electrode 1 to ensure that the microwave signal passes smoothly through the collector electrode, while microwave reflection and microwave loss are very small and can be ignored. The collector electrode 1 is insulated from the reflector tube body 6 and the reflector tube output section 9 by the insulating ceramic component 2. The collector electrode 1 is connected to about 1 / 2 of the cathode voltage.

[0032] The collecting electrode 1 is inserted into the return wave tube body 6 and the return wave tube output section 9. Thus, their internal tube diameters are not directly connected, but rather connected via a vacuum with a double "L" cross-section through an insulating ceramic component 2. The relatively long double "L" shaped space is shown in [the image / description]. Figure 5 As shown, this prevents electrons (including primary and secondary electrons) from hitting (or reaching) the insulating ceramic component 2, thus avoiding the failure of the insulating ceramic component 2.

[0033] The insulating ceramic component 2 is connected to the radial circular wall of the collecting electrode 1 via a metal sealing layer. The metal sealing layer consists of a coating layer applied to the surface of the circular ceramic component 2 and an electroplated layer covering the surface of the coating layer. The coating layer is made of one or more of molybdenum, manganese, and silicon dioxide, and the electroplated layer is made of nickel. This metal sealing ensures its airtightness.

[0034] In the double "L" space where the collecting electrode 1 is connected to the backwave tube body 6 and the backwave tube output section 9, the outer diameter of the collecting electrode 1 port is rounded because the voltage difference between the collecting electrode 1 and the backwave tube body 6 and the backwave tube output section 9 is relatively high, which makes it easy to generate field emission electrons.

[0035] The additional magnetic system 8 of the backwave tube body 6 can adjust its field value through simulation results, so that the electron beam reaches the lead plate of the collecting electrode directly in front of the center, which can effectively prevent X-ray leakage.

[0036] The collecting electrode 1 is wrapped with a lead sheet 4 and fixed by two or more lead sheet fixing rings 5, which can effectively block X-ray leakage.

[0037] The argon arc welded edge 3 of the step-down collecting electrode can be connected to the thin metal edge of the backwave tube body 6 or the backwave tube output part 9 in two ways: one is by argon arc welding, and the argon arc welding here must ensure airtightness; the other is that it can be fixed to the radial circular wall of the backwave tube body or the backwave tube output part by O-ring and bolts, which also ensures airtightness.

[0038] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments, but is not limited thereto.

[0039] Example 1

[0040] The insulating ceramic component 2 is connected to the collecting electrode 1 via a metal seal. The argon arc welded edge 3 is metal and is also connected to the insulating ceramic component via a metal seal layer. The metal seal layer not only provides high connection strength but also ensures airtightness. The argon arc welded edge 3 of the step-down collecting electrode can be welded to the thin metal edge of the retroreflector tube body 6 or the retroreflector output section 9 via argon arc welding, and the argon arc welding here must ensure airtightness. The argon arc welded edge 3 can also be fixed to the radial circular wall of the retroreflector tube body or the retroreflector output section via O-rings and bolts, again ensuring airtightness. A lead sheet 4 thicker than 10mm is fixed to the outside of the collecting electrode, such as... Figure 4 The location is shown. The lead sheet fixing ring is a metal ring that serves to secure the lead sheet. Two or more rings can be used until the lead sheet is completely fixed. There is a terminal on each of the two radial circular walls of the collecting electrode. The terminal is connected to approximately half the cathode voltage (its polarity is the same as the cathode voltage). The specific value is determined by referring to different RBWO electron interaction efficiencies.

[0041] Treating the backwave tube with the step-down collector as a system, ports 1 and 2 are as follows: Figure 5 As shown, the calculation result S21>99%, as... Figure 6 As shown, this means that the microwave transmission efficiency is almost unaffected after applying the voltage-reducing collector structure shown in this invention.

[0042] Example 2

[0043] Figure 7 and Figure 8 This is another example of the implementation of the present invention. Figure 7The insulating ceramic component 11 is tightly connected to the collecting electrode 1 and the output section 9 through a thermal expansion and contraction process. The connecting bolt 12 connects the return wave tube body 6 to the output section 9, with an O-ring seal in between to ensure airtightness. There are generally about 10 insulating ceramic components 11, which not only serve as insulation but also as support. Through the thermal expansion and contraction process, the output section 9, the collecting electrode 1, and the insulating ceramic component 11 are tightly bound together.

[0044] The electrode lead 13 of the collecting electrode is insulated from the output section 9 and the lead sheet 4 via the through-wall ceramic 14. The through-wall ceramic 14 is metal-sealed with the output section 9, and the contact surface between the through-wall ceramic 14 and the metal is metallized and sealed by brazing (e.g., using silver-copper solder) to ensure airtightness. The thin part of the through-wall ceramic 14 has normal threads, which can be tightened by rotating the insulating plastic cap. The inner core of the insulating plastic is connected to the high-voltage cable. The lead sheet fixing ring 5 is a metal ring that serves to fix the lead sheet 4. Three or four rings can be used, or multiple rings can be used until the lead sheet 4 is completely fixed. The electrode lead 13 passes through the through-wall ceramic 14 and is welded to the collecting electrode 1 via an arc-shaped metal wire 15. The arc-shaped metal wire 15 ensures that the lead 13 will not detach from the collecting electrode 1 due to thermal expansion and contraction.

[0045] The lead wire is connected to approximately half the cathode voltage (its polarity is the same as the cathode voltage). The specific value is determined by referring to the electron interaction efficiency of different RBWO circuits. A lead sheet 4, thicker than 10mm, is fixed to the outside of the output section 9. Figure 7 The lead sheet 4 is located at the same point as the output section 9 and the return wave tube body 6, and is generally grounded. Thus, the advantage of embodiment 2 is that the user does not have to directly face the high voltage, effectively protecting the user's safety.

Claims

1. A voltage-dropping collector electrode for use in a relativistic backward wave tube, characterized in that, include: The collector electrode is aligned with the central axis of the relativistic retroreflector. The inner diameter of the collector electrode input end is the same as the inner diameter of the retroreflector tube body, and the inner diameter of the collector electrode output end is the same as the inner diameter of the retroreflector tube output section. The radius gradually increases at the collector electrode inlet. The collector electrode is insulated from the retroreflector tube body and the retroreflector tube output section by an insulating ceramic component.

2. The voltage-dropping collector electrode for a relativistic backward wave tube according to claim 1, characterized in that, The collecting electrode is inserted into the backwave tube body and the output section of the backwave tube, and then connected through a vacuum with a double L cross section via an insulating ceramic component.

3. The voltage-dropping collector electrode for a relativistic backward wave tube according to claim 1, characterized in that, The insulating ceramic component is connected to the radial circular wall of the collecting electrode through a metal sealing layer. The metal sealing layer consists of a coating layer coated on the surface of the circular ceramic ring and an electroplated layer covering the surface of the coating layer.

4. The voltage-dropping collector electrode for a relativistic backward wave tube according to claim 1, characterized in that, Within the double "L" space connecting the collecting electrode to the backwave tube body and the backwave tube output section, the outer diameter of the collecting electrode port is rounded.

5. The voltage-dropping collector electrode for a relativistic backward wave tube according to claim 1, characterized in that, The additional magnetic system of the backwave tube body adjusts its field value based on simulation results, so that the electron beam reaches the lead plate of the collecting electrode directly in front of the center.

6. The voltage-dropping collector electrode for a relativistic backward wave tube according to claim 1, characterized in that, The collecting electrode is wrapped with a lead sheet and fixed by two or more lead sheet fixing rings.

7. The voltage-dropping collector electrode for a relativistic backward wave tube according to claim 1, characterized in that, The argon arc welded edge of the step-down collector electrode is connected to the thin metal edge of the backwave tube body or the output part of the backwave tube in two ways: one is by argon arc welding, and the other is by fixing it to the radial circular wall of the backwave tube body or the output part of the backwave tube through O-rings and bolts.

8. A voltage-dropping collector electrode for a relativistic backward wave tube according to claim 3, characterized in that, The coating layer is made of one or more of molybdenum, manganese, and silicon dioxide, and the electroplating layer is made of nickel.

9. A voltage-dropping collector electrode for use in a relativistic backward wave tube according to claim 1, characterized in that, The collecting electrode has a cylindrical structure with radial circular walls near both ends. The outer side of the radial circular walls is connected to the insulating ceramic component through a metal sealing layer. The cylindrical structure of the collecting electrode is divided into two parts: a cylindrical part, which serves as the output end, and a conical part, which serves as the input end. The thickness of the circumferential wall at one end of the cylindrical part of the collecting electrode is greater than the thickness of the circumferential wall at one end of the conical part of the collecting electrode.

10. A voltage-dropping collector electrode for a relativistic backward wave tube according to claim 6, characterized in that, The lead sheet is located on the outer surface of the collecting electrode between the two radial circular walls, and the fixing ring is fixed to the outer surface of the lead sheet.

11. A voltage-dropping collector electrode for use in a relativistic backward wave tube according to claim 1, characterized in that, The collector electrode, which is connected to a negative high voltage, is located inside the output section.

12. A voltage-dropping collector electrode for a relativistic backward wave tube according to claim 11, characterized in that, The lead wire connecting the collecting electrode is connected to the output section through an insulating ceramic component, and the connection between the metal and the insulating ceramic is achieved through a metal sealing process.

13. A voltage-dropping collector electrode for a relativistic backward wave tube according to claim 12, characterized in that, The lead wire is welded to the collecting electrode via an arc-shaped metal wire.

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