Hollow cathode insulating structure

Abstract

The utility model relates to electric propulsion technical field, propose a kind of hollow cathode insulation structure, including touch pole, gas supply pipe, insulating gasket, metal support, ceramic ring, base, touch pole insulation terminal and touch electrode.The utility model is embedded by touch pole insulation terminal and ceramic ring Occlusion, without increasing touch pole insulation terminal size can increase the insulation spacing between electrode;Meanwhile, the utility model reduces the gas pressure in pipe by the recess structure on base.The utility model reduces the possibility of abnormal sparking discharge while not increasing the number of components, improves the stability of insulation structure.The utility model structure is simple, and reliability is high, easy to assemble and mass production.

Description

Technical Field

[0001] This utility model generally relates to the field of electric propulsion technology. Specifically, this utility model relates to a hollow cathode insulation structure. Background Technology

[0002] The contact electrode is the core component of the hollow cathode for electric propulsion. During startup, an ignition voltage is applied between the contact electrode and the cathode top to break down the working gas, drawing out electrons to initiate the discharge and maintaining plasma stability during operation. Its structure includes insulating supports (ceramic rings and insulating terminals). To ensure that gas breakdown occurs only between the contact electrode top and the cathode top, and to prevent abnormal discharges between the contact electrode and other low-potential electrodes that could cause ignition failure, the design of the cathode insulation structure is particularly important. The high- and low-voltage electrodes inside the cathode involve end-face sealing between metal and ceramic. However, in existing technologies, effective sealing is not possible. Under high voltage, some gas can form a discharge circuit between the electrodes through the end-face gap, causing insulation failure. Furthermore, the risk of failure increases with the increase in gas supply flow. Traditional hollow cathode insulation structures generally improve insulation stability by increasing the size of the contact electrode insulating terminals. This increases the overall size and weight of the cathode envelope, which is detrimental to production and application. To improve cathode ignition reliability and reduce the complexity of the insulation structure, it is necessary to improve the design of the cathode insulation structure. Utility Model Content

[0003] Based on existing technology, the objective of this utility model is to provide a hollow cathode insulation structure that simplifies the insulation structure while improving the reliability of cathode ignition.

[0004] According to this utility model, the above-mentioned task is achieved by a hollow cathode insulation structure, the hollow cathode insulation structure comprising:

[0005] The base is constructed as a cylindrical structure, with an insertion hole at the center and a groove oriented radially along the base. A first through hole is provided at the edge of the groove, intersecting with the groove.

[0006] A ceramic ring is constructed as a cylindrical structure, with a first end being flat and a second end opposite to the first end having a protrusion, the surface of which has a second through hole penetrating the first end and the second end of the ceramic ring;

[0007] The contact electrode is constructed as a cylindrical structure, with an opening at the first end and a fourth through hole at the top of the second end opposite to the first end;

[0008] The contact electrode insulating terminal is constructed as a two-stage cylindrical structure and has a third through hole in the axial direction. The first end of the contact electrode insulating terminal is constructed to be embedded and engaged with the protrusion structure of the second end of the ceramic ring, and the second end opposite to the first end covers the groove above. The insulating gasket is constructed as a cylindrical structure and its end face is in contact with the first end of the contact electrode.

[0009] A metal support, the first end of which abuts against the insulating gasket, and the second end opposite to the first end abutting against the first end of the ceramic ring; and

[0010] The contact electrode is constructed as a two-stage cylindrical structure with different radii, wherein the smaller first stage abuts against the contact electrode insulating terminal, the ceramic ring, the metal support and the insulating gasket, and the larger second stage is configured to be inserted into the first through hole.

[0011] Furthermore, a threaded hole with a diameter of 2.5 mm is provided at the first end opening of the contact electrode.

[0012] Furthermore, the insulating pad is configured to have a fifth through hole in the axial direction, the axis of which coincides with the axis of the contact electrode threaded hole.

[0013] Furthermore, the metal bracket is configured to have a sixth through hole in the axial direction, the axis of the sixth through hole coinciding with the axis of the fifth through hole.

[0014] Furthermore, the contact electrode is configured to pass sequentially through the third through hole, the second through hole, the sixth through hole, and the fifth through hole, and is fastened to the threaded hole of the contact electrode.

[0015] Furthermore, the material of the contact electrode insulating terminal includes alumina ceramic.

[0016] Furthermore, the axial single-sided length of the engagement surface of the contact electrode insulating terminal is set to 4mm, and the radial single-sided thickness is set to 1mm.

[0017] Furthermore, the engagement gap between the ceramic ring and the contact electrode insulating terminal has a width of 0.1 mm in both the axial and radial directions.

[0018] Furthermore, the radial length of the groove is set to 4 mm, the width is set to 2 mm, and the depth is set to 1 mm.

[0019] Furthermore, the hollow cathode insulation structure also includes a gas supply pipe, which is arranged on the central axis of the hollow cathode insulation structure, and one end of which is welded and fixed in the insertion hole of the base.

[0020] This invention offers at least the following advantages: Compared to existing technologies, this invention increases the insulation distance between electrodes without increasing the size of the insulating terminals by embedding the insulating terminals of the contact electrode into the ceramic ring. Simultaneously, the groove structure on the base reduces the gas pressure inside the tube. This invention improves the upper limit of the contact electrode voltage (the cathode can also operate normally at a contact electrode voltage of 1000V) without increasing the number of components, reducing the possibility of abnormal arcing and discharge, and enhancing the stability of the insulation structure. This invention has a simple structure, high reliability, and is easy to assemble and mass-produce. Attached Figure Description

[0021] To further illustrate the advantages and other features of the various embodiments of this utility model, a more specific description of the embodiments of this utility model will be presented with reference to the accompanying drawings. It is understood that these drawings depict only typical embodiments of this utility model and are therefore not intended to limit its scope. In the drawings, for clarity, the same or corresponding parts will be indicated by the same or similar reference numerals.

[0022] Figure 1A and Figure 1B A schematic diagram of a hollow cathode insulation structure in one embodiment of the present invention is shown.

[0023] Figure 2 A schematic diagram of the base and groove structure of a hollow cathode insulation structure according to one embodiment of the present invention is shown.

[0024] Figure 3 A schematic diagram of a contact electrode insulating terminal structure of a hollow cathode insulating structure is shown in one embodiment of the present invention.

[0025] Figure 4 A schematic diagram of a potentially easily broken-down portion in a hollow cathode insulation structure according to one embodiment of the present invention is shown.

[0026] Explanation of reference numerals in the attached figures

[0027] 100 Hollow cathode insulation structure

[0028] 1. Contact electrode

[0029] 2. Gas supply pipe

[0030] 3 Insulating gaskets

[0031] 4. Metal bracket

[0032] 5 Ceramic Rings

[0033] 6. Contact pole insulated terminals

[0034] 7. Contact Electrode

[0035] 8 bases Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that the structures, proportions, sizes, etc., shown in this specification are only for illustrative purposes and to enable those skilled in the art to understand and read the invention. They are not intended to limit the implementation conditions of the present invention. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives of the present invention, should still fall within the scope of the technical content disclosed in the present invention.

[0037] In this utility model, the various embodiments are merely intended to illustrate the solution of this utility model and should not be construed as limiting.

[0038] In this utility model, unless otherwise specified, the quantifiers “one” and “one” do not exclude scenarios involving multiple elements.

[0039] It should also be noted that in the embodiments of this utility model, only a portion of the parts or components may be shown for clarity and simplicity. However, those skilled in the art will understand that, under the teachings of this utility model, the required parts or components can be added according to the specific scenario.

[0040] It should also be noted that in the description of this utility model, the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not explicitly or implicitly suggest that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0042] Figure 1A and Figure 1B A schematic diagram of a hollow cathode insulation structure according to one embodiment of the present invention is shown. Figure 1A and Figure 1B As shown, this utility model proposes a hollow cathode insulation structure 100, including a contact electrode 1, an air supply pipe 2, an insulating pad 3, a metal bracket 4, a ceramic ring 5, a base 8, a contact electrode insulating terminal 6, and a contact electrode 7.

[0043] The contact electrode 1 is a coaxial cylindrical structure with an opening at one end and a small hole at the other end. A threaded hole with a diameter of 2.5 mm is provided on its open end face.

[0044] The insulating pad 3 is a coaxial cylindrical structure, with its central axis coinciding with the central axis of the contact electrode 1. The insulating pad 3 is provided with a fifth through hole in the axial direction, and the axis of the hole coincides with the axis of the threaded hole on the end face of the contact electrode 1.

[0045] The metal bracket 4 abuts against one end of the insulating pad 3, and a sixth through hole is provided in the middle therein, the axis of which coincides with the axis of the fifth through hole;

[0046] The ceramic ring 5 abuts against the metal bracket 4, one end of which is a flat surface and the other end of which has a protrusion; the surface of the protrusion has a second through hole that penetrates the other end of the ceramic ring 5, and the axis of the second through hole coincides with the sixth through hole;

[0047] The contact electrode insulating terminal 6 has a two-stage cylindrical structure and a third through hole with uneven internal diameter in the axial direction. The contact electrode insulating terminal 6 is embedded and engaged with the protruding structure of the ceramic ring 5 through the third through hole. Preferably, the material of the contact electrode insulating terminal 6 is alumina ceramic.

[0048] The contact electrode 7 is a two-stage cylindrical structure. The smaller stage passes through the third through hole on the contact electrode insulating terminal 6, the second through hole on the ceramic ring 5, the sixth through hole on the metal bracket 4, and the fifth through hole on the insulating pad 3 in sequence, and is fastened to the threaded hole on the contact electrode 1.

[0049] Figure 2 A schematic diagram of the base and groove structure of a hollow cathode insulation structure according to one embodiment of the present invention is shown. Figure 2 As shown, the base 8 is a cylindrical structure with a central insertion hole for welding and fixing to the air supply pipe 2. The base has a 1mm deep groove with a radial length of 4mm and a width of 2mm. A first through hole is provided at the edge of the groove, tangent to one side of the groove. The larger-radius stage of the contact electrode 7 is installed in the first through hole.

[0050] Figure 3 A schematic diagram of a contact electrode insulating terminal structure of a hollow cathode insulating structure according to one embodiment of the present invention is shown. Figure 3 As shown, the interior of the contact electrode insulating terminal 6 is configured with a two-stage through-hole structure with different inner diameters. By inserting the protruding portion of the ceramic ring 5 into the through-hole of the contact electrode insulating terminal, an embedded interlocking structure can be formed. The interlocking edge length is 4mm, and the single-sided thickness is 1mm, ensuring sufficient structural strength. The interlocking surface of the contact electrode insulating terminal 6 has an interlocking gap of 0.1mm in both the axial and radial directions.

[0051] The functions of each component in a hollow cathode insulating structure according to one embodiment of this utility model are described below:

[0052] Contact electrode 1, which is configured to extract the working fluid and electron beam, is a key electrode component for extracting electrons in cathode discharge to achieve ignition discharge.

[0053] Gas supply pipe 2 is configured to deliver a working medium (such as gas) into the cathode to provide the working medium required for the cathode to operate;

[0054] Insulating pad 3 is configured to achieve insulation isolation between contact electrode 1 and metal support 4, while also helping to ensure the coaxiality of the components;

[0055] Metal bracket 4 is configured to maintain the coaxiality of the hollow cathode insulation structure and ensure accurate assembly of each component.

[0056] The ceramic ring 5 is configured to utilize the insulating properties of ceramics to increase the insulation distance between the contact electrode and the base through an interlocking structure, thereby improving insulation performance, while also serving to support and position the insulating terminals of the contact electrode.

[0057] The contact electrode insulating terminal 6 is configured to achieve insulation isolation between the contact electrode 7 and metal components such as the base 8, and works with the ceramic ring 5 to further extend the insulation path to prevent leakage or breakdown under high voltage.

[0058] Contact electrode 7, which is configured to conduct current and apply voltage to the contact electrode;

[0059] The base 8 is configured as a basic support component for the entire structure, while also venting gas from the bottom of the cathode through the groove, reducing the gas pressure in that area and decreasing the possibility of gas breakdown under high voltage.

[0060] The working principle of a hollow cathode insulation structure according to one embodiment of this utility model is described below:

[0061] Figure 4 This diagram illustrates a potentially easily broken-down portion of a hollow cathode insulation structure according to one embodiment of the present invention. Figure 4As shown, the potential gas path between the cathode bottom and the contact electrode is indicated by red and blue markings. Under high voltage, some gas can form a discharge circuit between the electrodes through the end face gap, causing insulation failure. The risk of failure increases with the increase in gas supply flow. In one embodiment of this invention, a hollow cathode insulation structure transforms the straight-line gas flow path into a zigzag path through the embedded engagement of the ceramic ring 5 and the contact electrode insulation terminal 6, thus extending the gas flow distance. Simultaneously, since the electron breakdown path is straight, the zigzag gas flow path reduces the possibility of ionization and breakdown of the gas under the influence of the electric field.

[0062] On the other hand, such as Figure 4 As indicated by the red and blue markings, abnormal gas breakdown between the contact electrode 7 and the base 8 is affected by the gas pressure at this location; breakdown discharge is more likely to occur under high gas pressure. In a hollow cathode insulation structure of one embodiment of this utility model, when gas enters the potential gas passage, it can flow out through the groove, thereby reducing the gas pressure at the rear end of the gas supply pipe 2, and further reducing the possibility of the hollow cathode insulation structure 100 undergoing discharge breakdown during ignition.

[0063] In short, the hollow cathode insulation structure in one embodiment of this utility model reduces the possibility of contact electrode insulation failure due to gas breakdown under high voltage by increasing the electrode insulation spacing and reducing the gas pressure at the rear end of the gas supply pipe, thereby improving the reliability of cathode operation.

[0064] Although various embodiments of the present invention have been described above, it should be understood that they are presented by way of example only and not as limitations. It will be apparent to those skilled in the art that various combinations, modifications, and alterations can be made without departing from the spirit and scope of the present invention. Therefore, the breadth and scope of the present invention disclosed herein should not be limited by the exemplary embodiments disclosed above, but should be defined solely by the appended claims and their equivalents.

Claims

1. A hollow cathode insulating structure, characterized by, include: The base is constructed as a cylindrical structure, with an insertion hole at the center and a groove oriented radially along the base. A first through hole is provided at the edge of the groove, intersecting with the groove. A ceramic ring is constructed as a cylindrical structure, with a first end being flat and a second end opposite to the first end having a protrusion, the surface of which has a second through hole penetrating the first end and the second end of the ceramic ring; The contact electrode insulating terminal is constructed as a two-stage cylindrical structure and has a third through hole in the axial direction. The first end of the contact electrode insulating terminal is constructed to be embedded and engaged with the protrusion structure of the second end of the ceramic ring, and its second end, which is opposite to the first end, covers the groove. The contact electrode is constructed as a cylindrical structure, with an opening at the first end and a fourth through hole at the top of the second end opposite to the first end; An insulating pad is constructed as a cylindrical structure, and its end face is in contact with the first end of the contact electrode; A metal bracket, the first end of which abuts against the insulating gasket, and the second end opposite to the first end abuts against the first end of the ceramic ring; as well as The contact electrode is constructed as a two-stage cylindrical structure with different radii, wherein the smaller first stage abuts against the contact electrode insulating terminal, the ceramic ring, the metal support and the insulating gasket, and the larger second stage is configured to be inserted into the first through hole.

2. The hollow cathode insulation structure according to claim 1, characterized in that, A threaded hole is provided at the first end opening of the contact electrode, and the diameter of the threaded hole is set to 2.5 mm.

3. The hollow cathode insulation structure according to claim 1, characterized in that, The insulating pad is configured to have a fifth through hole in the axial direction, the axis of which coincides with the axis of the threaded hole of the contact pole.

4. A hollow cathode insulation structure according to claim 3, characterized in that, The metal bracket is configured to have a sixth through hole in the axial direction, the axis of which coincides with the axis of the fifth through hole.

5. A hollow cathode insulation structure according to claim 4, characterized in that, The contact electrode is configured to pass sequentially through the third through hole, the second through hole, the sixth through hole, and the fifth through hole, and is fastened to the threaded hole of the contact electrode.

6. A hollow cathode insulation structure according to claim 1, characterized in that, The material of the contact electrode insulating terminal includes alumina ceramic.

7. A hollow cathode insulation structure according to claim 6, characterized in that, The axial single-sided length of the engagement surface of the contact electrode insulating terminal is set to 4mm, and the radial single-sided thickness is set to 1mm.

8. A hollow cathode insulation structure according to claim 7, characterized in that, The engagement gap between the ceramic ring and the contact electrode insulating terminal is set to 0.1 mm in both the axial and radial directions.

9. A hollow cathode insulation structure according to claim 1, characterized in that, The radial length of the groove is set to 4 mm, the width is set to 2 mm, and the depth is set to 1 mm.

10. A hollow cathode insulation structure according to claim 1, characterized in that, It also includes a gas supply pipe, which is arranged on the central axis of the hollow cathode insulation structure, and one end of which is welded and fixed in the socket of the base.

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