High stability liquid cooling side-beam microfocus x-ray tube and packaged x-ray tube

Abstract

The application provides a high-stability liquid-cooled side-beam microfocus X-ray tube and a packaged X-ray tube. The high-stability liquid-cooled side-beam microfocus X-ray tube comprises a tube shell, a cathode assembly, an anode assembly and a window assembly. The anode assembly comprises an anode handle, an anode target, a sealed end cover assembly and a cooling assembly. The anode handle is a hollow structure and is provided with a liquid cooling cavity. The anode target comprises a target base part fixedly sealed at one end of the anode handle and a target material. The sealed end cover assembly is fixedly sealed at the other end of the anode handle. The cooling assembly comprises an anode liquid inlet pipe and an anode liquid outlet pipe both fixedly sealed to the sealed end cover assembly. One end of the anode liquid inlet pipe extends into the liquid cooling cavity, is adjacent to the target base part and is in communication with the liquid cooling cavity. One end of the anode liquid outlet pipe is in communication with the liquid cooling cavity. In this way, the cooling liquid directly impacts the target base part of the anode target, provides sufficient cooling capacity, so that the target material has higher power bearing capacity when used for microfocus, has higher light flux and higher stability.

Description

Technical Field

[0001] This invention relates to the field of X-ray technology, and particularly to the field of X-ray scientific instruments, specifically to a highly stable liquid-cooled side-exit microfocus X-ray tube, and a packaged X-ray tube equipped with the highly stable liquid-cooled side-exit microfocus X-ray tube. Background Technology

[0002] The lower the energy of X-rays, the easier they are to attenuate. Side-exit microfocus X-ray tubes, because the X-rays do not pass through glass and insulating oil for attenuation, are widely used in high-end X-ray scientific instruments requiring low-energy X-rays (such as microfocal X-ray diffractometers, micro-area X-ray fluorescence spectrometers, and small-angle X-ray scattering instruments). X-ray scientific instruments require high X-ray flux, and also require high stability in the magnitude of the flux and the spatial position of the focal spot. This necessitates microfocus X-ray tubes with high target energy density and high heat dissipation capabilities.

[0003] In traditional encapsulated X-ray tubes, the anode target in the anode assembly uses a conventional copper-encased tungsten target structure. This structure has insufficient heat dissipation capacity, making it difficult to withstand high power when the focal point on the target surface is at the micrometer scale (microfocal point). This results in a low target surface energy density (power divided by the target surface focal area), leading to insufficient X-ray flux. Furthermore, the high-voltage layout of side-ejection microfocal X-ray tubes uses a cathode-grounded, anode-high-voltage configuration. To achieve high-voltage insulation of the anode, the entire anode assembly is immersed in insulating silicone or insulating oil. Consequently, the large amount of heat generated by the electron beam bombarding the anode target is difficult to dissipate quickly, resulting in insufficient heat dissipation. This temperature rise causes significant thermal drift in the focal point's spatial position, leading to low focal point spatial stability. Additionally, the high heat capacity of the insulating silicone or insulating oil requires a long time to reach thermal equilibrium, causing the focal point's spatial position to stabilize over an extended period. Therefore, scientific instruments using this type of encapsulated X-ray tube require a long waiting time before they can be used.

[0004] Furthermore, in traditional side-exit microfocus X-ray tubes, the cathode and anode assemblies are arranged opposite each other but do not overlap in the axial direction. This structure causes secondary electrons to accumulate on the insulating shell of the X-ray tube, resulting in changes in the spatial electric field and even arcing, which affects the stability of the electron beam and thus leads to instability in the light flux.

[0005] In addition, some existing X-ray tubes use liquid cooling structures for their anode components. For example, an X-ray tube disclosed in Chinese Utility Model Patent No. CN212010898U has an axially extending blind hole in the anode and a cooling medium outlet on the outer periphery of the blind hole. At the same time, a cooling medium inlet pipe is set in the blind hole. The cooling medium is transported to the inside of the blind hole through the cooling medium inlet pipe and then leaves the anode through the cooling medium outlet. However, this X-ray tube still has the following shortcomings: the anode has a blind hole structure, which cannot effectively cool the target material. Therefore, the power that the X-ray tube anode can withstand is still not high, and the light flux is still insufficient. In particular, the cooling medium outlet on the anode is connected to the external area of ​​the X-ray tube. The cooling medium flowing out of the outlet merges with the insulating silicone or insulating oil soaking the X-ray tube. That is, the cooling system of the anode cannot circulate independently, resulting in low cooling efficiency. The thermal equilibrium time is long (because it needs to circulate together with the insulating silicone or insulating oil soaking the X-ray tube, and the heat capacity is large). Ultimately, this leads to limited power, insufficient light flux, limited long-term stability of light flux, and low spatial stability of the focal spot, making it difficult to meet the needs of high-end X-ray scientific instruments, especially in high-end application fields such as semiconductors. Summary of the Invention

[0006] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a highly stable liquid-cooled side-exit micro-focus X-ray tube, which enables the target surface to withstand high target energy density while supporting independent cyclic cooling, thereby improving the luminous flux and luminous flux stability, improving the spatial position stability of the focus, and reducing the time required for the spatial position of the focus to stabilize.

[0007] To achieve the above objectives, the present invention provides a highly stable liquid-cooled side-exit microfocus X-ray tube, comprising a tube shell, a cathode assembly sealed and fixed at one end of the tube shell for emitting an electron beam, an anode assembly sealed and fixed at the other end of the tube shell, and a window assembly fixed on the tube shell. The anode assembly includes an anode stalk, an anode target, a sealing end cap assembly, and a cooling assembly.

[0008] The anode shank is a hollow structure with an axially penetrating liquid-cooled cavity inside. The anode target includes a target base bottom sealed and fixed to one end of the anode shank facing the cathode assembly, and a target material fixed to the surface of the target base bottom. The sealing end cap assembly is sealed and fixed to the other end of the anode shank. The two ends of the liquid-cooled cavity are sealed by the target base bottom and the sealing end cap assembly, respectively.

[0009] The cooling assembly includes an anode inlet pipe and an anode outlet pipe, both sealed and fixed to the sealing end cap assembly. One end of the anode inlet pipe extends into the liquid cooling cavity, is close to the bottom of the target base, and communicates with the liquid cooling cavity. One end of the anode outlet pipe is also communicated with the liquid cooling cavity. The other ends of both the anode inlet pipe and the anode outlet pipe are used to connect to an external cooling circulation system.

[0010] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is as follows: the sealing end cap assembly includes a first sealing end cap and a second sealing end cap. The first sealing end cap is sealed and fixed to the end of the anode shank and blocks the liquid-cooled cavity. The first sealing end cap has several liquid-cooled through holes. The second sealing end cap is sealed and fixed to the side of the first sealing end cap facing away from the anode shank and forms a liquid-cooled transition cavity between the second and the first sealing end cap. The liquid-cooled cavity and the liquid-cooled transition cavity are connected through several liquid-cooled through holes.

[0011] The anode inlet pipe is fixedly inserted into the first and second sealing end caps, the anode outlet pipe is fixed to the second sealing end cap, and one end of the anode outlet pipe is connected to the liquid-cooled transition cavity.

[0012] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is as follows: the anode inlet pipe is welded and sealed to both the first and second sealing end caps; the anode outlet pipe is welded and sealed to the second sealing end cap; the first and second sealing end caps are welded and sealed to each other; and a sealing ring is provided between the end of the anode shank and the first sealing end cap.

[0013] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is that the anode inlet pipe is coaxially arranged with the anode stalk.

[0014] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is as follows: the cathode assembly is connected to a negative high voltage, and the anode assembly is grounded.

[0015] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is as follows: the bottom of the target substrate is directly welded and sealed to the end of the anode handle, and the target material is plated on the surface of the bottom of the target substrate.

[0016] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is as follows: the bottom of the target substrate is a diamond substrate, and the target material is any one of copper, silver, chromium, tungsten, molybdenum, rhodium, gold, iron, and SiC.

[0017] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is as follows: the anode assembly further includes an anode Kovar cover, a Kovar connecting cover, and an anode shielding cover, all fitted around the anode stalk. The anode stalk has a radially protruding stalk flange on its outer periphery. One end of the anode Kovar cover is sealed and fixedly connected to the stalk flange. Both ends of the Kovar connecting cover are respectively sealed and fixedly connected to the other end of the anode Kovar cover and the tube shell. One end of the anode shielding cover is sealed and fixedly connected to the stalk flange and is disposed inside the tube shell.

[0018] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is that the cathode assembly and the anode assembly are coaxially arranged, and the cathode assembly and the anode assembly partially overlap in the axial direction.

[0019] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is as follows: a focusing electrode is provided at one end of the cathode assembly near the anode assembly; one end of the anode shank with the anode target fixed therein extends into the focusing electrode; a first opening is provided on the focusing electrode; and the center of the anode target, the first opening, and the window assembly are aligned radially.

[0020] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is as follows: a focusing electrode is provided at one end of the cathode assembly near the anode assembly; a radially protruding shank flange is provided on the outer periphery of the anode shank, and a shank shield extending axially from the outer end of the shank flange toward the cathode assembly; the anode target is located inside the shank shield; the focusing electrode extends into the shank shield; a second opening is provided on the shank shield; and the center of the anode target, the second opening, and the window assembly are radially aligned.

[0021] Furthermore, a preferred embodiment of the high-stability liquid-cooled side-exit microfocus X-ray tube is as follows: the tube shell is provided with a radially extending side window connection portion, the window assembly includes a window flange, a beryllium window sealed and fixed inside the window flange, a connecting glass shell disposed on the outer periphery of the window flange, and a mounting flange, the connecting glass shell extending radially along the tube shell, the two ends of the connecting glass shell being sealed and fixed to the side window connection portion and the window flange respectively, and the mounting flange being sealed and fixed on the outer periphery of the connecting glass shell.

[0022] The present invention also provides an encapsulated X-ray tube, comprising a cylindrical assembly filled with an insulating medium, and a high-stability liquid-cooled side-exit microfocus X-ray tube as described above. The cylindrical assembly is provided with a radially penetrating side fixing port, the high-stability liquid-cooled side-exit microfocus X-ray tube is disposed inside the cylindrical assembly, and the tube shell is sealed and fixed to the cylindrical assembly at the side fixing port.

[0023] As described above, the high-stability liquid-cooled side-exit microfocus X-ray tube and packaged X-ray tube of the present invention have the following beneficial effects:

[0024] 1. The anode shank in this application has a hollow structure, with an internal liquid-cooled cavity axially extending through it. The bottom of the anode target base is fixed to one end of the anode shank and seals one end of the liquid-cooled cavity. Combined with the structural design where the anode inlet pipe extends into the liquid-cooled cavity and its outlet port is close to the bottom of the target base, the cooling liquid can directly impact the anode target base, providing sufficient cooling capacity. This allows the target material to have higher power handling capacity when used for micro-focusing, resulting in X-rays with higher luminous flux and greater stability.

[0025] 2. In this application, the anode inlet pipe and anode outlet pipe of the cooling assembly are both connected to an external cooling circulation system. The cooling liquid supplied by the external cooling circulation system flows into the liquid-cooled cavity through the anode inlet pipe and then returns to the external cooling circulation system through the anode outlet pipe. Therefore, the cooling circulation loop formed by the anode inlet pipe, the liquid-cooled cavity, the anode outlet pipe, and the external cooling circulation system is an independent cooling circulation loop within the tube. This independent cooling circulation loop is isolated from the insulating silicone or insulating oil outside the X-ray tube. This allows for the use of other, more efficient cooling liquids besides insulating silicone or insulating oil to cool the anode target, further improving cooling efficiency. Simultaneously, the independent cooling circulation structure within the tube reduces the heat capacity of the X-ray tube and effectively shortens the thermal equilibrium time, thereby increasing the target power density and improving the time required for focal point spatial position stabilization and spatial position stability.

[0026] 3. In this application, the cathode assembly and the anode assembly partially overlap in the axial direction. By having the anode assembly extend into the cathode assembly or the cathode assembly extend into the anode assembly, the stability of the field strength distribution between the cathode assembly and the anode assembly is improved, thereby improving the stability of the electron beam current between the cathode and anode. Therefore, the stability of the luminous flux, the spatial position of the focal spot, and the size of the focal spot can be improved. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a high-stability liquid-cooled side-exit microfocus X-ray tube according to Embodiment 1 of this application.

[0028] Figure 2 for Figure 1 A partial sectional view.

[0029] Figure 3 for Figure 2 A schematic diagram of the structure of the anode handle.

[0030] Figure 4 This is a partial cross-sectional view of Embodiment 2 of the high-stability liquid-cooled side-exit microfocus X-ray tube of this application.

[0031] Figure 5 This is a schematic diagram of the encapsulated X-ray tube of this application.

[0032] Component labeling: Tube shell 10, side window connection 11, cathode assembly 20, focusing electrode 21, first opening 211, anode assembly 30, anode target 31, target base bottom 301, anode handle 32, liquid cooling cavity 321, handle flange 322, handle shield 323, second opening 324, anode inlet pipe 33, anode outlet pipe 34, first sealing end cap 35, liquid cooling through hole 351, second sealing end cap 36, liquid cooling transition cavity 37, sealing ring 38, anode Kovar cover 39, Kovar connection cover 310, anode shield 311, window assembly 40, window flange 41, beryllium window 42, connecting glass shell 43, mounting flange 44, cylinder assembly 50, inlet connection pipe 61, outlet connection pipe 62. Detailed Implementation

[0033] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0034] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and objectives of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0035] It should also be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or may be connected to an intermediary component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component through an intermediary component.

[0036] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

[0037] This invention relates to the field of X-ray technology, specifically to a highly stable liquid-cooled side-exit microfocus X-ray tube, and a packaged X-ray tube equipped with the highly stable liquid-cooled side-exit microfocus X-ray tube.

[0038] like Figure 1 As shown, the high-stability liquid-cooled side-exit microfocus X-ray tube involved in this application includes a tube shell 10 with an internal vacuum environment, a cathode assembly 20 sealed and fixed to one end of the tube shell 10, an anode assembly 30 sealed and fixed to the other end of the tube shell 10, and a window assembly 40 fixed to the tube shell 10. Figure 2 and Figure 3 As shown, the anode assembly 30 includes an anode shank 32, an anode target 31, a sealing end cap assembly, and a cooling assembly. The anode shank 32 has a hollow structure, and an axially penetrating liquid-cooled cavity 321 is provided inside the anode shank 32. That is, the liquid-cooled cavity 321 has a through-hole structure, and both ends of the liquid-cooled cavity 321 pass through both ends of the anode shank 32. The anode target 31 includes a target base bottom 301 sealed and fixed on one end of the anode shank 32 facing the cathode assembly 20, and a target material fixed on the surface of the target base bottom 301. The sealing end cap assembly is sealed and fixed on the other end of the anode shank 32. Thus, both ends of the liquid-cooled cavity 321 are sealed by the target base bottom 301 and the sealing end cap assembly, respectively, and both ends of the liquid-cooled cavity 321 are directly connected to the target base bottom 301 and the sealing end cap assembly. The cooling assembly includes an anode inlet pipe 33 and an anode outlet pipe 34, both sealed and fixed to the sealing end cap assembly. The anode inlet pipe 33 extends into the liquid cooling chamber 321. One end of the anode inlet pipe 33 is close to the bottom 301 of the target base and communicates with the liquid cooling chamber 321. One end of the anode outlet pipe 34 is also communicated with the liquid cooling chamber 321. The other ends of both the anode inlet pipe 33 and the anode outlet pipe 34 are connected to an external cooling circulation system, which provides cooling liquid.

[0039] like Figure 5As shown, the encapsulated X-ray tube involved in this application includes a cylindrical assembly 50 filled with an insulating medium, and the aforementioned high-stability liquid-cooled side-emitting microfocus X-ray tube. The cylindrical assembly 50 has a radially penetrating side fixing port. The high-stability liquid-cooled side-emitting microfocus X-ray tube is disposed inside the cylindrical assembly 50. The tube shell 10 is sealed and fixed to the cylindrical assembly 50 at the side fixing port, thereby fixing the high-stability liquid-cooled side-emitting microfocus X-ray tube as a whole inside the cylindrical assembly 50. The cathode assembly 20 and anode assembly 30 of the high-stability liquid-cooled side-emitting microfocus X-ray tube are both immersed in the insulating medium inside the cylindrical assembly 50. The insulating medium is insulating silicone or insulating oil. In addition, the radial direction mentioned in this application refers to the direction perpendicular to the axial direction of the encapsulated X-ray tube.

[0040] During exposure in the encapsulated X-ray tube, the electron beam emitted and focused by the cathode assembly 20 is accelerated by the electric field and bombards the target material of the anode target 31 of the anode assembly 30, producing X-rays, which are then emitted from the window assembly 40. During exposure, only a very small portion of the electron kinetic energy of the electron beam bombarding the target material of the anode target 31 is converted into X-rays; the majority of the energy is deposited as heat on the target material of the anode target 31, causing the anode target 31 to generate a large amount of heat, which is also transferred to the anode shank 32. During exposure in the encapsulated X-ray tube, the external cooling circulation system provides cooling liquid that flows into the liquid-cooled cavity 321 inside the anode shank 32 through the anode inlet pipe 33. The cooling liquid in the liquid-cooled cavity 321 then flows back to the external cooling circulation system through the anode outlet pipe 34. This cycle carries away the heat from the anode shank 32 and the anode target 31, achieving heat dissipation for the anode assembly 30.

[0041] In this application, the anode shank 32 has a hollow structure, with one end of its internal liquid-cooled cavity 321 directly connected to the bottom 301 of the target base of the anode target 31. Simultaneously, the anode inlet pipe 33 extends into the liquid-cooled cavity 321, and its outlet port is close to the bottom 301 of the target base. Therefore, the cooling liquid flowing from the anode inlet pipe 33 forcibly and directly impacts the bottom 301 of the target base of the anode target 31, rapidly cooling it and providing sufficient cooling capacity. This gives the X-ray tube high heat dissipation capacity, allowing the target material to have higher power handling capacity, higher luminous flux, and higher stability when used for microfocal focusing. Thus, the X-ray tube of this application is a highly stable liquid-cooled side-ejection microfocal X-ray tube, capable of producing X-rays with higher luminous flux and higher stability. Furthermore, based on the cooling structure where the cooling liquid directly connects to the bottom 301 of the target base of the anode target 31, the heat from the anode assembly 30 can be quickly and promptly dissipated, resulting in a more stable anode temperature, less thermal drift at the focal point, and higher stability of the focal point position. Furthermore, the cryogenic cooling liquid can ensure that the anode assembly 30 of the entire X-ray tube operates in a low-temperature environment for a long time, effectively preventing the anode assembly 30 from releasing gas due to high temperature, thus giving the X-ray tube involved in this application a longer service life.

[0042] In particular, the anode inlet pipe 33 and anode outlet pipe 34 involved in the cooling assembly of this application are both connected to an external cooling circulation system. The cooling liquid supplied by the external cooling circulation system flows into the liquid-cooled cavity 321 through the anode inlet pipe 33, and then flows back to the external cooling circulation system through the anode outlet pipe 34. That is, the cooling circulation loop composed of the anode inlet pipe 33, the liquid-cooled cavity 321, the anode outlet pipe 34 and the external cooling circulation system is an independent cooling circulation loop inside the tube. This independent cooling circulation loop inside the tube is isolated from the insulating silicone or insulating oil outside the X-ray tube. Therefore, other more efficient cooling liquids besides insulating silicone or insulating oil can be introduced into the liquid-cooled cavity 321 to cool the anode target 31, further improving the cooling efficiency. For example, when the X-ray tube adopts a structure with the anode grounded and the cathode connected to a negative high voltage, the anode assembly 30 does not involve high voltage insulation issues, and there are no requirements for the insulation capability of the cooling liquid. Cooling water can be used as the cooling liquid. When an X-ray tube adopts a structure with the anode connected to high voltage and the cathode grounded, there are requirements for the insulation capability of the cooling liquid. Deionized water, insulating silicone, insulating oil, etc., can be used as cooling liquids, which can reduce the high-voltage insulation requirements for the cathode assembly 20. At the same time, the adoption of an independent cooling circulation structure inside the tube can also reduce the heat capacity of the X-ray tube and effectively shorten the thermal equilibrium time of the X-ray tube.

[0043] Preferably, in the high-stability liquid-cooled side-exit microfocus X-ray tube involved in this application, the cathode assembly 20 is connected to a negative high voltage and the anode assembly 30 is grounded, so that a water-cooled circulation structure can be used in the anode assembly 30 to achieve a high heat dissipation rate at low cost.

[0044] Furthermore, the high-stability liquid-cooled side-exit microfocus X-ray tube involved in this application is also a high-stability, high-flux microfocus diamond composite target X-ray tube. Specifically, the target base bottom 301 is made of a high thermal conductivity material, such as one or more combinations of diamond, copper, aluminum, and graphene, preferably diamond. Therefore, the target base bottom 301 is preferably a diamond substrate. The target material is any one of copper, silver, chromium, tungsten, molybdenum, rhodium, gold, iron, and SiC. The diamond substrate is directly welded and sealed to the end of the anode shank 32, preferably by brazing, to achieve connection, fixation, and vacuum sealing. Target metals such as silver or copper are plated onto the surface of the diamond substrate. Thus, after the anode target 31 adopts a composite target structure with a diamond substrate plated with target metals such as silver or copper, the ultra-high thermal conductivity of diamond effectively dissipates and conducts away the target temperature. Combined with the structure where the cooling liquid delivered by the anode inlet pipe 33 directly impacts the diamond substrate, rapid cooling is achieved. Thus, a higher power density can be achieved at the target point, resulting in a high target energy density in the X-ray tube, higher brightness and focus stability, and the emission of brighter X-rays. Furthermore, the anode target 31 in this application does not have a target base; it is a baseless structure. Instead, a micro-focus diamond composite target (i.e., the anode target 31) with a diamond substrate plated with target metal is directly brazed to the end of the anode shank 32. This avoids the problem of reduced heat transfer efficiency caused by voids in the welding between the anode target 31 and the target base, thereby further improving the cooling effect. In other embodiments, an intermediate layer material can be selectively provided between the target base bottom 301 and the target material. The intermediate layer material is preferably one or a combination of Ti and Cr.

[0045] Preferably, the anode shank 32 is made of copper, which has good thermal conductivity, effectively transferring heat from the anode target 31 and improving the heat dissipation performance of the anode assembly 30. The housing 10 is a glass shell.

[0046] Furthermore, such as Figure 2As shown, the anode inlet pipe 33 is coaxially arranged with the anode shank 32. The sealing end cap assembly includes a first sealing end cap 35 and a second sealing end cap 36. The first sealing end cap 35 is sealed and fixed to the end of the anode shank 32 and blocks the liquid cooling cavity 321. The first sealing end cap 35 has several axially penetrating liquid cooling through holes 351, which are arranged around the periphery of the anode inlet pipe 33. The second sealing end cap 36 is sealed and fixed to the side of the first sealing end cap 35 facing away from the anode shank 32 and forms a liquid cooling transition cavity 37 between the second sealing end cap 36 and the first sealing end cap 35. The liquid cooling cavity 321 and the liquid cooling transition cavity 37 are connected through the several liquid cooling through holes 351. The anode inlet pipe 33 is fixedly inserted through the first sealing end cap 35 and the second sealing end cap 36. The anode outlet pipe 34 is fixed to the second sealing end cap 36, and one end of the anode outlet pipe 34 is connected to the liquid cooling transition cavity 37. With this configuration, the cooling liquid flowing out of the anode inlet pipe 33 impacts the anode target 31 and flows in the liquid cooling chamber 321. It then flows into the liquid cooling transition chamber 37 through the liquid cooling through hole 351 and then flows back to the external cooling circulation system through the anode outlet pipe 34, thus achieving efficient heat dissipation for the anode assembly 30.

[0047] Preferably, such as Figure 2 As shown, the anode inlet pipe 33 is welded and sealed to the first sealing end cap 35 and the second sealing end cap 36. The anode outlet pipe 34 is welded and sealed to the second sealing end cap 36. The first sealing end cap 35 and the second sealing end cap 36 are welded and sealed together. A sealing ring 38 is provided between the end of the anode shank 32 and the first sealing end cap 35, which facilitates fixing and ensures sealing. The first sealing end cap 35 and the second sealing end cap 36 are both made of stainless steel. The fixing method between the first sealing end cap 35 and the anode shank 32 is preferably bolt fixing, adhesive fixing, or threaded engagement. The fixing method between the second sealing end cap 36 and the first sealing end cap 35 is preferably bolt fixing or adhesive fixing.

[0048] Furthermore, such as Figure 2 As shown, the anode assembly 30 also includes an anode Kovar cover 39, a Kovar connecting cover 310, and an anode shield 311, all fitted around the anode shank 32. The anode shank 32 has a radially protruding shank flange 322 on its outer periphery. One end of the anode Kovar cover 39 is sealed and fixedly connected to the shank flange 322. Both ends of the Kovar connecting cover 310 are sealed and fixedly connected to the other end of the anode Kovar cover 39 and the housing 10, respectively. One end of the anode shield 311 is sealed and fixedly connected to the shank flange 322 and is disposed inside the housing 10. Thus, the anode shank 32, made of metal, is sealed and fixedly fixed within the glass housing through the anode Kovar cover 39 and the Kovar connecting cover 310. Preferably, the anode shield 311 is brazed to the shank flange 322. The Kovar connecting cover 310 can be Kovar glass or Kovar ceramic.

[0049] Furthermore, such as Figure 2 As shown, the tube shell 10 has a radially open structure, and a radially extending side window connection portion 11 is integrally provided at its radially open side opening. The window assembly 40 includes a window flange 41, a beryllium window 42 sealed and fixed within the window flange 41, a connecting glass shell 43 disposed on the outer periphery of the window flange 41, and a mounting flange 44. Both the window flange 41 and the connecting glass shell 43 extend straight along the radial direction of the tube shell 10. The two ends of the connecting glass shell 43 are respectively sealed and fixed to the side window connection portion 11 and the window flange 41. The mounting flange 44 is sealed and fixed on the outer periphery of the connecting glass shell 43, and the mounting flange 44 is fixedly connected to the cylinder assembly 50 at the side fixing port. In this way, the window assembly 40 is fixed at the radially open side of the tube shell 10, and the high-stability liquid-cooled side-exit microfocus X-ray tube and the cylinder assembly 50 are fixedly connected through the mounting flange 44. This application employs a side-ejection beam structure, eliminating the obstruction of glass, cooling insulating oil, and window material of the tube shell 10 along the X-ray path. Only a thin beryllium window 42 is present, significantly reducing X-ray attenuation and thus achieving higher light throughput. Furthermore, during production, the window assembly 40 is first sintered and fixed to the tube shell 10, then the cathode assembly 20 and anode assembly 30 are connected to the tube shell 10 to form a vacuum-sealed X-ray tube. Finally, the cooling assembly is fixed to the end of the anode shank 32, forming a complete anode-water-cooled X-ray tube.

[0050] Furthermore, such as Figure 2 or Figure 4 As shown, the cathode assembly 20 and the anode assembly 30 are coaxially arranged, and the cathode assembly 20 and the anode assembly 30 partially overlap in the axial direction, that is, the end of the cathode assembly 20 extends into the interior of the anode assembly 30, or the end of the anode assembly 30 extends into the interior of the cathode assembly 20. Based on this, the high-stability liquid-cooled side-exit microfocus X-ray tube has two preferred embodiments.

[0051] In Example 1 of the high-stability liquid-cooled side-exit microfocus X-ray tube, such as Figure 2As shown, a focusing electrode 21 is provided at one end of the cathode assembly 20 near the anode assembly 30. One end of the anode shank 32, to which the anode target 31 is fixed, extends into the focusing electrode 21. The focusing electrode 21 has a first opening 211 through which X-rays generated by the anode target 31 pass. In this structure, the end of the anode assembly 30 extends into the interior of the cathode assembly 20. Stray electrons from the focused electron beam and secondary electrons bounced or rebounded from the anode target 31 are blocked and shielded by the focusing electrode 21 of the cathode assembly 20, significantly reducing the number of electrons reaching the tube shell 10 and reducing the accumulation of secondary electrons on the tube shell 10. This reduces the changes in cathode and anode field strength caused by the accumulation of secondary electrons and lowers the risk of arcing, thereby improving the stability of the high-stability liquid-cooled side-exit micro-focus X-ray tube, namely, improving the stability of luminous flux, focal spatial position, and focal size. Furthermore, the target surface of the anode target 31 and the body of the anode shank 32 extend into the cathode assembly 20. The electric field strength between the cathode and anode is completely determined by the structure between the cathode and anode. Changes in potential and electric field outside the cathode and anode structure will not affect the electric field strength between the cathode and anode, that is, they will not affect the focused electron beam. Therefore, it can provide stability of light flux, stability of focal spatial position and stability of focal size.

[0052] Preferably, such as Figure 2 As shown, the center of the anode target 31, the first opening 211, and the window assembly 40 are aligned radially, meaning that the axes of the center of the anode target 31, the center of the first opening 211, and the window assembly 40 are collinear, so that the X-rays generated by the anode target 31 pass through the first opening 211 of the cathode assembly 20 and then exit from the beryllium window 42 of the window assembly 40.

[0053] In Example 2 of the high-stability liquid-cooled side-exit microfocus X-ray tube, such as Figure 4 As shown, a focusing electrode 21 is provided at one end of the cathode assembly 20 near the anode assembly 30. The outer periphery of the anode shank 32 has a radially protruding shank flange 322 and a shank shield 323 extending axially from the outer end of the shank flange 322 toward the cathode assembly 20. The anode target 31 is located inside the shank shield 323, and the focusing electrode 21 extends into the shank shield 323. The shank shield 323 has a second opening 324 through which X-rays generated by the anode target 31 pass. In this structure, the end of the cathode assembly 20 extends into the interior of the anode assembly 30, and the anode shank 32 and the window assembly 40 are at the same potential. The negative high voltage of the cathode assembly 20 is shielded by the anode shank 32, thereby avoiding the risk of high-voltage arcing between the cathode assembly 20 and the window assembly 40, and improving the stability and reliability of the X-ray tube.

[0054] Preferably, such as Figure 4As shown, the center of the anode target 31, the second opening 324, and the window assembly 40 are aligned radially, meaning that the axes of the center of the anode target 31, the center of the second opening 324, and the window assembly 40 are collinear, so that the X-rays generated by the anode target 31 pass through the second opening 324 of the anode assembly 30 and then exit from the beryllium window 42 of the window assembly 40.

[0055] Preferably, such as Figure 5 As shown, the cylinder assembly 50 has an inlet connection pipe 61 and an outlet connection pipe 62 sealed and fixed at the end near the anode assembly 30. The inlet connection pipe 61 is connected between the anode inlet pipe 33 and the external cooling circulation system, and the outlet connection pipe 62 is connected between the anode outlet pipe 34 and the external cooling circulation system.

[0056] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0057] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A high-stability liquid-cooled side-emission microfocus X-ray tube, comprising a tube shell (10), a cathode assembly (20) sealed and fixed at one end of the tube shell (10) for emitting an electron beam, an anode assembly (30) sealed and fixed at the other end of the tube shell (10), and a window assembly (40) fixed on the tube shell (10), characterized in that: The anode assembly (30) includes an anode shank (32), an anode target (31), a sealing end cap assembly, and a cooling assembly; The anode shank (32) is a hollow structure with an axially penetrating liquid-cooled cavity (321) inside. The anode target (31) includes a target base bottom (301) sealed and fixed at one end of the anode shank (32) facing the cathode assembly (20), and a target material fixed on the surface of the target base bottom (301). The sealing end cap assembly is sealed and fixed at the other end of the anode shank (32). The two ends of the liquid-cooled cavity (321) are sealed by the target base bottom (301) and the sealing end cap assembly, respectively. The cooling assembly includes an anode inlet pipe (33) and an anode outlet pipe (34) that are both sealed and fixed to the sealing end cap assembly. One end of the anode inlet pipe (33) extends into the liquid cooling cavity (321) and is close to the bottom of the target base (301) and communicates with the liquid cooling cavity (321). One end of the anode outlet pipe (34) is communicated with the liquid cooling cavity (321). The other ends of the anode inlet pipe (33) and the anode outlet pipe (34) are both used to connect to an external cooling circulation system.

2. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 1, characterized in that: The sealing end cap assembly includes a first sealing end cap (35) and a second sealing end cap (36). The first sealing end cap (35) is sealed and fixed to the end of the anode shank (32) and blocks the liquid cooling cavity (321). The first sealing end cap (35) has several liquid cooling through holes (351). The second sealing end cap (36) is sealed and fixed to the side of the first sealing end cap (35) facing away from the anode shank (32) and forms a liquid cooling transition cavity (37) between the second sealing end cap (35) and the first sealing end cap (35). The liquid cooling cavity (321) and the liquid cooling transition cavity (37) are connected through several liquid cooling through holes (351). The anode inlet pipe (33) is fixedly inserted in the first sealing end cap (35) and the second sealing end cap (36), and the anode outlet pipe (34) is fixed to the second sealing end cap (36). One end of the anode outlet pipe (34) is connected to the liquid cooling transition cavity (37).

3. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 2, characterized in that: The anode inlet pipe (33) is welded and sealed to the first sealing end cap (35) and the second sealing end cap (36). The anode outlet pipe (34) is welded and sealed to the second sealing end cap (36). The first sealing end cap (35) and the second sealing end cap (36) are welded and sealed to each other. A sealing ring (38) is provided between the end of the anode shank (32) and the first sealing end cap (35).

4. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 1, characterized in that: The anode inlet pipe (33) is coaxial with the anode handle (32).

5. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 1, characterized in that: The cathode assembly (20) is connected to a negative high voltage, and the anode assembly (30) is grounded.

6. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 1, characterized in that: The target base bottom (301) is directly welded and sealed to the end of the anode handle (32), and the target material is plated on the surface of the target base bottom (301).

7. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 1 or 6, characterized in that: The target base (301) is a diamond substrate, and the target material is any one of copper, silver, chromium, tungsten, molybdenum, rhodium, gold, iron, and SiC.

8. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 1, characterized in that: The anode assembly (30) further includes an anode Kovar cover (39), a Kovar connecting cover (310), and an anode shield (311) fitted around the anode shank (32). The anode shank (32) has a radially protruding shank flange (322) on its outer periphery. One end of the anode Kovar cover (39) is sealed and fixedly connected to the shank flange (322). Both ends of the Kovar connecting cover (310) are sealed and fixedly connected to the other end of the anode Kovar cover (39) and the tube shell (10), respectively. One end of the anode shield (311) is sealed and fixedly connected to the shank flange (322) and is located inside the tube shell (10).

9. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 1, characterized in that: The cathode assembly (20) and the anode assembly (30) are coaxially arranged, and the cathode assembly (20) and the anode assembly (30) partially overlap in the axial direction.

10. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 9, characterized in that: The cathode assembly (20) is provided with a focusing electrode (21) at one end near the anode assembly (30). The anode shank (32) is fixed with one end of the anode target (31) extending into the focusing electrode (21). The focusing electrode (21) is provided with a first opening (211). The center of the anode target (31), the first opening (211) and the window assembly (40) are aligned radially.

11. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 9, characterized in that: The cathode assembly (20) has a focusing electrode (21) at one end near the anode assembly (30). The outer periphery of the anode shank (32) has a radially protruding shank flange (322) and a shank shield (323) extending axially from the outer end of the shank flange (322) toward the cathode assembly (20). The anode target (31) is located inside the shank shield (323). The focusing electrode (21) extends into the shank shield (323). The shank shield (323) has a second opening (324). The center of the anode target (31), the second opening (324), and the window assembly (40) are radially aligned.

12. The high-stability liquid-cooled side-exit microfocus X-ray tube according to claim 1, characterized in that: The shell (10) is provided with a radially extending side window connection (11). The window assembly (40) includes a window flange (41), a beryllium window (42) sealed and fixed inside the window flange (41), a connecting glass shell (43) provided on the outer periphery of the window flange (41), and a mounting flange (44). The connecting glass shell (43) extends radially along the shell (10). The two ends of the connecting glass shell (43) are respectively sealed and fixed to the side window connection (11) and the window flange (41). The mounting flange (44) is sealed and fixed on the outer periphery of the connecting glass shell (43).

13. A packaged X-ray tube, comprising a cylindrical assembly (50) internally filled with an insulating medium, the cylindrical assembly (50) having a radially penetrating side fixing port, characterized in that: It also includes the high-stability liquid-cooled side-exit micro-focus X-ray tube according to any one of claims 1-12, wherein the high-stability liquid-cooled side-exit micro-focus X-ray tube is disposed inside the cylindrical assembly (50), and the tube shell (10) is sealed and fixed to the cylindrical assembly (50) at the side fixing port.

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