A cathode heater assembly for a klystron electron gun

Abstract

The embodiment of the present invention discloses a cathode thermal subassembly for a klystron electron gun, comprising: a cathode base; a cathode disposed on the top of the cathode base; a thermal subassembly located in the cathode base; a heat shield fixed in the cathode base, the heat shield being disposed below the thermal subassembly; and a cathode base disposed at the bottom of the cathode base, the cathode base being configured to reduce the heat conduction of the thermal subassembly; the cathode base being a basket-shaped structure, comprising a first ring body, a second ring body, and a plurality of support rods disposed between the first ring body and the second ring body, the two ends of the support rods being respectively fixed to the first ring body and the second ring body; the first ring body and the second ring body being disposed in parallel and concentrically. By designing the cathode base at the connection between the electron gun cathode thermal subassembly and the klystron cavity structure into a basket-shaped structure, heat conduction is effectively reduced, the stability of the electron gun is improved, and the life of the klystron is extended.

Description

Technical Field

[0001] The present invention relates to the technical field of high-power klystron tubes, and more specifically to a cathode heater assembly for a klystron electron gun. Background Art

[0002] A high-power klystron is a microwave vacuum device that converts electron beam energy into microwave energy based on the principle of speed modulation. In a high-power klystron, due to the generation and formation of the electron beam, the interaction between the electron beam and the microwave field, the dissipation of the electron residual energy and the output of the microwave energy are carried out in separate spaces, and its high-frequency interaction system is a separate resonant cavity, so it has the advantages of high power, high gain, high efficiency, high stability and long life.

[0003] In microwave vacuum electronic devices such as klystrons, electron beams are the medium for generating and amplifying microwave power. Electron beams are formed by the emission of electrons from hot cathodes. Therefore, hot cathodes play an important role and are the heart of the device. The realization of high-performance and long-life devices is closely related to high-performance cathodes. In addition, the heaters and heater components required for cathode heating also have an important impact on the reliability and life of the device.

[0004] Important performance indicators of the cathode are operating temperature, emission current density and life. As the heating component of the cathode, the structure and preparation process of the heater will affect the heating efficiency of the cathode, the start-up time, reliability and life of the klystron. The traditional klystron electron gun cathode heater structure usually adopts a stacked heat shield structure and grooves on the cathode base to reduce heat conduction. However, due to the large contact area, the heat conduction efficiency is still very high. Summary of the invention

[0005] To solve the above problems, the present invention provides a cathode heater assembly for a klystron electron gun, so as to reduce the thermal conductivity of the conventional klystron cathode heater assembly structure, thereby improving the stability of the electron gun and extending the life of the klystron.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A cathode heater assembly for a klystron electron gun, comprising:

[0008] cathode base;

[0009] A cathode disposed on the top of the cathode base;

[0010] a thermal subassembly located within the cathode base;

[0011] In combination with a heat shield fixed in the cathode base, the heat shield is disposed below the thermal subassembly; and

[0012] a cathode base disposed at the bottom of the cathode base, the cathode base being configured to reduce heat conduction of the thermal subassembly;

[0013] The cathode base is a basket-shaped structure, comprising a first ring body, a second ring body, and a plurality of support rods disposed between the first ring body and the second ring body, wherein both ends of the support rods are respectively combined and fixed with the first ring body and the second ring body;

[0014] The first ring body and the second ring body are arranged parallel and concentrically.

[0015] In addition, a preferred solution is that the first ring body is connected to the cathode base.

[0016] In addition, a preferred solution is that a first mounting groove is provided on the first ring body, and a second mounting groove is provided on the second ring body;

[0017] Two ends of the support rod are respectively assembled in the first mounting groove and the second mounting groove.

[0018] In addition, a preferred solution is that the heat shield has three layers, which are, from top to bottom, a first heat shield layer, a second heat shield layer and a third heat shield layer.

[0019] Furthermore, it is preferred that the thermal subassembly is located between the cathode and the heat shield.

[0020] In addition, it is preferred that the thermal subassembly comprises:

[0021] Hot plate tray;

[0022] A hot wire ring fixed on the heating sub-tray; and

[0023] Ceramic beads are sleeved on the heating wire ring at equal intervals.

[0024] In addition, a preferred solution is that the heating wire ring includes a first heating wire ring and a second heating wire ring which are arranged concentrically;

[0025] The first heating wire ring and the second heating wire ring are connected by a heating wire.

[0026] In addition, a preferred solution is that the first heating wire ring and the second heating wire ring are formed by winding spring-shaped heating wires.

[0027] In addition, a preferred solution is that the thermal sub-assembly also includes a fixing belt, and the ceramic beads are fixed to the thermal sub-tray via the fixing belt.

[0028] In addition, a preferred solution is that the thermal sub-tray is fixedly combined with the cathode base and the heat shield.

[0029] The beneficial effects of this application are as follows:

[0030] In view of the technical problems existing in the prior art, the embodiment of the present application provides a cathode thermal subassembly for a klystron electron gun, by designing the cathode base at the connection between the electron gun cathode thermal subassembly and the klystron cavity structure into a basket-shaped structure, the setting of this structure can effectively reduce the heat conduction from the thermal subassembly to the cathode base, and reduce the weight of the assembly, thereby improving the stability of the electron gun and extending the life of the klystron. In addition, in this embodiment, the thermal subassembly is designed as a concentric circle plane structure, and the porcelain beads fix the shape of the hot wire ring while ensuring insulation, so that the hot wire ring is not easy to deform under the high temperature state of power on, so that during the preheating process of the thermal subassembly, the cathode can be evenly heated in a very short time, thereby improving the thermal stability of the thermal subassembly during operation and extending the service life of the cathode. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0032] Figure 1 A cross-sectional view of a conventional cathode heater assembly for a klystron electron gun is shown.

[0033] Figure 2 A cross-sectional view of a cathode heater assembly for a klystron electron gun provided by an embodiment of the present invention is shown.

[0034] Figure 3 A cross-sectional view of a cathode thermal subassembly provided in an embodiment of the present invention is shown.

[0035] Figure 4 A schematic structural diagram of a thermal subassembly provided in an embodiment of the present invention is shown.

[0036] Figure 5 A schematic structural diagram of a cathode base provided in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0037] 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.

[0038] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0039] It should also be noted that, in the description of the present application, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of further restrictions, the elements defined by the statement "comprise one..." do not exclude the presence of other identical elements in the process, method, article or equipment including the elements.

[0040] The operating life of a high-power klystron depends on the life of the electron gun, which in turn depends on factors such as the cathode operating temperature, vacuum maintenance, and the electric field strength on the cathode surface. Reducing the heating power of the electron gun can reduce the overall average temperature of the electron gun thermal subassembly, so that the heating power is concentrated on the cathode emission surface, which can improve the working stability of the electron gun and extend the cathode working life. Figure 1 This is a cross-sectional view of a cathode thermal subassembly for a conventional klystron electron gun. Typically, a stacked heat shield structure is used and grooves are cut on the cathode base to reduce heat conduction between the thermal subassembly and the bottom of the cathode base (the direction of the arrow in the figure is the direction of heat conduction). However, due to the large area of ​​the cathode base, the heat conduction efficiency is still very high.

[0041] In order to overcome the defects of the prior art, the embodiment of the present invention provides a cathode heater assembly for a klystron electron gun, Figure 2-5As shown, the cathode thermal subassembly for the klystron electron gun includes a cathode base 1, a cathode 2, a thermal subassembly 3, a thermal shield 4 and a cathode base 5. In this embodiment, the interior of the cathode base 1 is a hollow structure, and the thermal subassembly 3 and the thermal shield 4 are both arranged inside the cathode base 1. The thermal shield 4 is fixedly combined with the inner wall of the cathode base 1, and the thermal subassembly 3 is fixedly combined with the upper surface of the thermal shield 4. The existence of the thermal shield 4 effectively reduces the outward radiation of the heat generated by the cathode in a vacuum. The cathode 2 is arranged on the top of the cathode base 1. The thermal subassembly 3 generates heat after being energized. The generated heat is transferred to the cathode 2, and the cathode 2 is activated by the heat to release electrons. The cathode base 5 is arranged at the bottom of the cathode base 1, as shown in FIG. Figure 2 as well as Figure 5 As shown in the figure, the cathode base 5 is a basket-shaped structure, which can effectively reduce the heat conduction between the thermal subassembly and the cathode base while ensuring stable support, and also reduce the weight of the cathode thermal subassembly, thereby improving the stability of the klystron and extending its service life.

[0042] In this embodiment, the cathode base 5 includes a first ring body 51, a second ring body 52, and a support rod 53 disposed between the first ring body 51 and the second ring body 52, and the two ends of the support rod 53 are respectively fixed to the first ring body 51 and the second ring body 52. ​​Specifically, the first ring body 51 and the second ring body 52 are arranged in parallel and concentrically. When assembling the cathode base 5, the first ring body 51 is rotated around its own axis by a certain angle to facilitate the connection of the support rod 53 to form a basket-shaped structure. It should be noted that this embodiment does not limit the number of support rods 53, and it is only required that the cathode base 5 can reduce the heat conduction between the thermal subassembly and the cathode base while ensuring the stability of the support.

[0043] In this embodiment, the first ring body 51 includes a first mounting groove 510 for mounting the support rod 53, and the second ring body 52 includes a second mounting groove 520 for mounting the support rod 53. Both ends of the support rod 53 are fixed in the first mounting groove 510 and the second mounting groove 520, and there is a certain gap between adjacent support rods, forming a Figure 5 Compared with the prior art, this embodiment adds a cathode base 5 at the connection between the electron gun cathode thermal subassembly and the klystron cavity structure. The cathode base 5 is composed of a first ring body 51, a second ring body 52 and a support rod 53 located between the two for connection, forming a unique basket-shaped structure, which can effectively reduce the contact area, thereby reducing the heat conduction between the thermal subassembly and the cathode base, thereby achieving the effect of improving the stability of the electron gun and extending the life of the klystron.

[0044] In a specific embodiment, the bottom outer diameter of the cathode base 1 matches the inner diameter of the first ring body 51, and the cathode base 5 is connected to the cathode base 1 through the first ring body 51, providing effective support for the cathode thermal sub-assembly and reducing the heat conduction between the thermal sub-assembly and the cathode base by reducing the contact area.

[0045] In one embodiment, the number of the heat shield 4 is three layers, which are the first heat shield layer 41, the second heat shield layer 42 and the third heat shield layer 43 from top to bottom. The three heat shield layers are concentric and parallel to each other and are arranged at a specific distance below the thermal subassembly 3. The arrangement of the heat shield 4 effectively reduces the outward radiation of heat generated by the cathode in a vacuum and reduces the heat conduction between the thermal subassembly and the cathode base. It should be noted that the present invention does not limit the number of layers of the heat shield 4, and the number of layers of the heat shield can be adjusted according to demand during the actual production process.

[0046] In this embodiment, the thermal subassembly 3 is located between the cathode 2 and the heat shield 4 , specifically, located on a side of the first heat shield layer 41 away from the second heat shield layer 42 .

[0047] In a specific embodiment, the thermal subassembly 3 includes a thermal sub-tray 31, a hot wire ring 32 and a porcelain bead 33, and the hot wire ring 32 and the porcelain bead 33 are both fixed on the thermal sub-tray 31. The existence of the porcelain bead 33 insulates the hot wire ring 32 from the thermal sub-tray 31, and the porcelain bead 33 is sleeved on the hot wire ring 32. Specifically, the number of the porcelain beads 33 is multiple, and the multiple porcelain beads 33 can be arranged on the hot wire ring 32 at equal intervals. In other embodiments, the distances between the porcelain beads 33 may also be unequal, and this application does not limit this.

[0048] In one embodiment, the heat sub-assembly further includes a fixing belt 34, which is sleeved on the ceramic bead 33 and is used to fix the hot wire ring 32 to the heat sub-tray 31. The hot wire ring 32 and the ceramic bead 33 are both fixed to the heat sub-tray 31 by the fixing belt 34 on the ceramic bead 33. Specifically, the fixing belt includes but is not limited to a tantalum-niobium belt.

[0049] In this embodiment, the hot wire ring 32 includes a first hot wire ring 321 and a second hot wire ring 322. The diameter of the first hot wire ring 321 is larger than the diameter of the second hot wire ring 322. The second hot wire ring 322 is arranged inside the ring of the first hot wire ring 321. The first hot wire ring 321 and the second hot wire ring 322 are arranged concentrically and connected by hot wires. The structural design of the hot wire ring 32 is to ensure that the cathode 2 is heated evenly and to weaken the magnetic field generated when the current passes through, so as to ensure the working stability of the cathode 2.

[0050] In this embodiment, the first heating wire ring 321 and the second heating wire ring 322 are both formed by firstly winding the heating wire into a spring shape and then winding it into a ring shape.

[0051] In one embodiment, the outer edge of the thermal tray 31 is fixedly coupled to the inner circle of the cathode base 1 , and the bottom of the thermal tray 31 is fixedly coupled to the heat shield 4 . Specifically, the bottom surface of the thermal tray 31 is fixedly coupled to the upper surface of the first heat shield layer 41 .

[0052] The cathode heat subassembly for the klystron electron gun provided in this embodiment effectively reduces the thermal conductivity of the conventional klystron cathode heat subassembly and reduces the weight of the assembly by designing the cathode base 5 at the connection between the electron gun cathode heat subassembly and the klystron cavity structure into a basket-shaped structure, thereby improving the stability of the electron gun and extending the life of the klystron. In addition, the present application designs the heat subassembly 3 into a concentric circle plane structure, and the porcelain beads 33 fix the shape of the hot wire ring 32 while ensuring insulation, so that the hot wire ring 32 is not easy to deform under the high temperature state of power on, ensuring that the cathode 2 is evenly heated in a very short time during the preheating process of the heat subassembly 3, improving the thermal stability of the heat subassembly 3 during operation, and extending the service life of the cathode 2.

[0053] 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 cathode heater assembly for a klystron electron gun, characterized in that: include: cathode base; A cathode disposed on the top of the cathode base; a thermal subassembly located within the cathode base; In combination with a heat shield fixed in the cathode base, the heat shield is arranged below the thermal subassembly; as well as a cathode base disposed at the bottom of the cathode base, the cathode base being configured to reduce heat conduction of the thermal subassembly; The cathode base is a basket-shaped structure, comprising a first ring body, a second ring body, and a plurality of support rods disposed between the first ring body and the second ring body, wherein both ends of the support rods are respectively combined and fixed with the first ring body and the second ring body; The first ring body and the second ring body are arranged parallel and concentrically; The thermal subassembly comprises: Hot plate tray; A hot wire ring fixed on the heating sub-tray; and Ceramic beads are sleeved on the heating wire ring at equal intervals; The hot wire ring comprises a first hot wire ring and a second hot wire ring which are arranged concentrically; The first heating wire ring and the second heating wire ring are connected by a heating wire.

2. The cathode heater assembly for a klystron electron gun according to claim 1, characterized in that: The first ring body is connected to the cathode base.

3. The cathode heater assembly for a klystron electron gun according to claim 1, characterized in that: The first ring body is provided with a first mounting groove, and the second ring body is provided with a second mounting groove; Two ends of the support rod are respectively assembled in the first mounting groove and the second mounting groove.

4. The cathode heater assembly for a klystron electron gun according to claim 1, characterized in that: The heat shield has three layers, which are the first heat shield layer, the second heat shield layer and the third heat shield layer from top to bottom.

5. The cathode heater assembly for a klystron electron gun according to claim 4, characterized in that: The thermal subassembly is located between the cathode and the heat shield.

6. The cathode heater assembly for a klystron electron gun according to claim 1, characterized in that: The first heating wire ring and the second heating wire ring are formed by winding spring-shaped heating wires.

7. The cathode heater assembly for a klystron electron gun according to claim 1, characterized in that: The heat sub-assembly also includes a fixing belt, and the ceramic beads are fixed on the heat sub-tray through the fixing belt.

8. The cathode heater assembly for a klystron electron gun according to claim 1, characterized in that: The thermal sub-tray is combined and fixed with the cathode base and the heat shield.

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