An X-ray tube with an anode forced cooling structure and a cooling pipeline structure

Abstract

The present invention discloses an X-ray tube with an anode forced cooling structure and a cooling pipeline structure, which includes a cathode, a tube shell, an anode, a radiator, and a cooling pipeline. The anode includes an anode cap, an anode target, a target head, and a target body. One end of the main pipeline of the cooling pipeline is communicated with the inlet end of the outlet fixed end plate. There are multiple sub-pipelines, and the end of the target head is provided with bottom holes consistent with the number and arrangement of the sub-pipelines. One end of each sub-pipeline is communicated with the main pipeline, and the other end is correspondingly inserted into the bottom holes at the corresponding positions. The outlet fixed end plate is provided with a number of outlet end through holes. The outlet fixed end plate is fixed to the outer end face of the radiator, and the outer end face of the radiator is provided with a through hole with a diameter larger than the diameter of the inner cavity of the target body and communicated with the inner cavity of the target body, and the position of the through hole corresponds to the position of the outlet end through hole. The present invention can greatly improve the heat dissipation efficiency, ensure that the working temperature is very effectively reduced when the power is increased, and ensure the stability of long-term continuous operation.

Description

Technical Field

[0001] The present invention relates to the technical field of X-ray tubes, and more particularly to an X-ray tube having an anode forced cooling structure and a cooling pipeline structure. Background Art

[0002] When an X-ray tube is operating, only about 1% of the electron beam energy is converted into X-rays, and the remaining 99% is converted into heat energy deposited on the anode, which will cause the temperature of the anode to rise sharply. The heat energy is mainly concentrated on the anode target part (anode target and adjacent anode body) that receives the electron beam bombardment, which is equivalent to a heat source. When the temperature exceeds the tolerance of the anode, the vacuum degree of the X-ray tube will rapidly decrease, and the voltage withstand capacity will drop sharply, resulting in a complete failure of the operation. Therefore, how to reduce the anode temperature has always been one of the key points in the design and manufacture of X-ray tubes.

[0003] Currently, the demands for high-voltage X-ray tubes (≥250 kV) are mainly concentrated in two major application fields: security inspection and industrial flaw detection. The working methods of the two are significantly different: the security inspection field adopts a real-time scanning continuous working method; the industrial flaw detection field adopts an intermittent pulse working method. The former has more stringent requirements for continuous power than the latter, that is, during long-term continuous operation, it is required that there are no or very few phenomena such as arcing and microdischarge that seriously affect the image quality. The latter has higher requirements for absolute power because it pursues higher image quality, even several times that of the former, but it does not have such high requirements for continuous power. However, the current trend in both fields is the same, that is, there is an increasing demand for higher power.

[0004] The continuous increase in power will inevitably lead to a higher anode temperature. The traditional cooling methods are natural cooling or air cooling, mainly for dissipating heat from the radiator or the whole of the X-ray tube. However, this is far from sufficient for such high-voltage and high-power tube types. Therefore, targeted direct forced cooling of the anode, especially the anode target part, is a more superior and effective heat dissipation method.

[0005] Currently, for anode forced cooling technologies, a forced cooling system is installed close to the anode target part or a cooling pipeline is formed, and then water or oil is used as the coolant for cooling. The most commonly used technology is to open a cavity in the anode body, with a depth close to the anode target. Then a pipeline (usually made of metal) is inserted, which together with the cavity in the anode body forms the pipeline for the coolant to enter and exit. Since there is only one cavity in the anode body, the cooling pipeline extending to the anode target position is only an injection port. This structure is relatively simple and direct to implement. Although it has a cooling effect, the contact area between the coolant and the anode target part is limited, and the heat exchange area is not sufficient. Summary of the Invention

[0006] In view of the deficiencies of the prior art, the present invention aims to provide an X-ray tube with an anode forced cooling structure and a cooling pipeline structure, which can greatly improve the heat dissipation efficiency, effectively reduce the working temperature when the power is increased, and ensure the stability of long-term continuous operation.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] An X-ray tube with an anode forced cooling structure and a cooling pipeline structure, comprising a cathode, a tube shell, an anode, and a radiator; the cathode is arranged inside the tube shell; one end of the anode is arranged inside the tube shell, and the other end is located outside the tube shell; the radiator is fixed to the other end of the anode; the anode includes an anode cap, an anode target, a target head, and a target body, one end of the target head is fixed inside the cavity at the other end of the target body, the anode cap covers the other end of the target head and is connected to the target body, and the anode target is embedded in the other end of the target head by vacuum casting; it also includes a cooling pipeline, which includes a main pipeline, sub-pipelines, and an outlet fixing end plate; one end of the main pipeline is connected to the inlet end of the outlet fixing end plate; there are multiple sub-pipelines, and the target head is provided with bottom holes at one end that are consistent with the number and arrangement of the sub-pipelines; one end of each sub-pipeline is connected to the main pipeline, and the other end extends into the corresponding bottom hole in a matching manner; the outlet fixing end plate is provided with a number of outlet end through holes; the outlet fixing end plate is fixed to the outer end face of the radiator, and the outer end face of the radiator is provided with a through hole with a diameter larger than the diameter of the inner cavity of the target body and communicating with the inner cavity of the target body, and the position of the through hole corresponds to the position of the outlet end through holes.

[0009] Furthermore, the angle between the end face formed by the arrangement of all the bottom holes of the target head near the anode target and the end face formed by the arrangement of the other ends of all the sub-pipelines and the target face of the anode target is less than 5°.

[0010] Even further, the target face of the anode target is inclined, and the end face formed by the arrangement of all the bottom holes of the target head near the anode target and the end face formed by the arrangement of the other ends of all the sub-pipelines are both inclined.

[0011] Furthermore, the diameter of the main pipeline is larger than the diameter of the sub-pipelines.

[0012] Furthermore, the tube shell is made of glass material.

[0013] Furthermore, the vertical distance between the end face formed by the arrangement of all the bottom holes of the target head near the anode target and the target face of the anode target is 10 - 12 mm.

[0014] The beneficial effects of the present invention are as follows: The anode forced cooling structure and the cooling pipeline structure adopted by the present invention can greatly increase the heat exchange area of the anode target part and more effectively reduce the target surface temperature. At the same time, in the present invention, the input of the coolant is completed through a main pipeline and multiple sub-pipelines, and the output of the coolant is realized through the outlet end through holes on the outlet fixed end plate. The structure is simple and the number of vacuum sealing positions is small. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the X-ray tube in Embodiment 1 of the present invention;

[0016] Figure 2 It is a sectional view of the assembly structure of the anode, radiator and cooling pipeline in Embodiment 1 of the present invention;

[0017] Figure 3 It is a schematic diagram of the structure of the target head in Embodiment 1 of the present invention;

[0018] Figure 4 It is a schematic diagram of the structure of the cooling pipeline in Embodiment 1 of the present invention;

[0019] Figure 5 It is a schematic diagram of the overall structure of the X-ray tube in Embodiment 2 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The present invention will be further described below with reference to the accompanying drawings. It should be noted that this embodiment is based on the present technical solution and gives detailed implementation manners and specific operation processes, but the protection scope of the present invention is not limited to this embodiment.

[0021] Embodiment 1

[0022] This embodiment provides an X-ray tube with an anode forced cooling structure and a cooling pipeline structure, which is mainly applied to the field of security inspection. As Figure 1As shown, the X-ray tube includes a cathode 204, a tube housing 205 (made of glass in this embodiment), an anode 201, a radiator 203, and a cooling pipeline 202; the cathode 204 is disposed inside the tube housing 205; one end of the anode 201 is disposed inside the tube housing 205, and the other end is located outside the tube housing; the radiator 203 is fixed to the other end of the anode 201, and one end of the cooling pipeline 202 extends into the anode 201, and the other end passes through the radiator 203 and communicates with the outside. Specifically, the cathode 204 and the anode 201 are encapsulated inside the tube housing 205, and a high vacuum inside the tube housing is achieved through a vacuum exhaust process. The radiator 203 is installed on the other end of the anode outside the tube housing by means of thermal expansion or press fitting. The part inside the tube housing 205 is in a high vacuum environment, which requires strict vacuum tightness, but the part outside the tube housing does not need to be in a vacuum environment, including the other end of the anode 201 outside the tube housing 205, the radiator 203, and the cooling pipeline 202.

[0023] Figure 2 is a detailed assembly sectional view of the anode, the radiator, and the cooling pipeline. The anode includes an anode cap 307, an anode target 306, a target head 301, and a target body 302. One end of the target head 301 is fixed to the inner cavity of the other end of the target body 302. The anode cap 307 covers the other end of the target head 301 and is connected to the target body 302. The anode target 306 is embedded in the other end of the target head 301. A bottom hole 3011 is provided at one end of the target head 301. One end of the cooling pipeline 202 passes through the inner cavity of the target body 302 and extends out to the outside through the radiator 203, and the other end extends into the bottom hole 3011. The bottom hole 3011 on the target head 301 and the target body 302 together form a cavity for accommodating the cooling pipeline 202. The anode target 306 is embedded in the target head 301 by means of vacuum casting. The anode cap 307, the target head 301, and the target body 302 are hermetically connected by vacuum welding.

[0024] Figure 3 is a structural schematic diagram of the target head, Figure 4 is a structural schematic diagram of the cooling pipeline. As Figure 4As shown, the cooling pipeline includes a main pipeline 501, sub-pipelines 502 and an outlet fixed end plate 503; one end of the main pipeline 501 is communicated with the inlet end 504 of the outlet fixed end plate 503; there are multiple sub-pipelines 502, and one end of the target head 301 is provided with bottom holes 3011 that are consistent with the number and arrangement of the sub-pipelines 502; one end of each sub-pipeline 502 is communicated with the main pipeline 501, and the other end extends into the corresponding bottom hole 3011 in a matching manner; the end faces formed by arranging the other ends of all sub-pipelines 502 are parallel or approximately parallel to the target surface of the anode target 306; the outlet fixed end plate 503 is provided with a number of outlet end through holes 505; the outlet fixed end plate 503 is fixed to the outer end face of the radiator 203 by screws, and the outer end face of the radiator 203 is provided with a through hole with a diameter larger than the diameter of the target inner cavity, and the position of the through hole corresponds to the position of the outlet end through hole 505 to facilitate the coolant to flow out from the outlet end through hole 505; in this embodiment, the main pipeline 501, the sub-pipelines 502 and the outlet fixed end plate 503 are connected into one body by welding or firmly pasting.

[0025] In this embodiment, the target surface of the anode target 306 is inclined, so the depths of the bottom holes 3011 between the rows of the target head 301 are different, and the heights between the rows of sub-pipelines 502 are also different, but the depths of the bottom holes 3011 in the same row are the same, and the heights of the sub-pipelines 502 in the same row are the same. The height of each sub-pipeline 502 is consistent with the depth of the corresponding through hole 3011. The vertical distance between the end face formed by arranging all the bottom holes of the target head 301 close to the anode target 306 and the target surface of the anode target 306 is about 10-12 mm. This distance can not only play a good cooling role for the anode target, but also ensure the vacuum tightness at this place. The end faces formed by arranging the ends of all the bottom holes of all the target heads 301 close to the anode target 306 and the end faces formed by arranging the other ends of all the sub-pipelines 502 are all inclined and approximately parallel to the target surface of the anode target 306, and the included angle is less than 5°.

[0026] In this embodiment, the diameter of the main pipeline 501 is larger than the diameter of the sub-pipelines 502.

[0027] The working principle of the X-ray tube with the anode forced cooling structure and the cooling pipeline structure is as follows: During operation, the coolant is injected into the main pipeline 501 from the inlet end 504 of the outlet fixed end plate 503, first shunted into each sub-pipeline 502, and then injected into the bottom holes 3011 of each row of the target head 301. Since the anode target is cast into the target head, when the anode target is heated, it will conduct heat to the target head. The coolant cools the part of the target head 301 closest to the anode target 306, which can cause a temperature difference between the target head 301 and the anode target 306 for heat exchange. During the continuous cooling of the target head by the coolant, this heat exchange will also continue accordingly, thereby realizing the cooling effect on the anode target. Then, during the process of the coolant flowing out of the target head 301, the remaining parts of the target head 301 and the target body 302 are cooled. The heat-exchanged coolant finally flows out through the inner cavity of the target body 302 towards the radiator and out to the outside through the outlet end through hole of the outlet fixed end plate.

[0028] Since the target head is a porous structure, compared with the prior art, the heat exchange area with the anode target part can be significantly increased, and this part is exactly the hottest place during the operation of the entire X-ray tube. Therefore, it is a more superior and effective cooling structure.

[0029] Embodiment 2

[0030] This embodiment is basically the same as Embodiment 1. The main difference is that, as Figure 5 shown, the tube shell 205 in this embodiment is wavy, so that the working voltage of the X-ray tube is increased to 300 kV, the tube working current is 1.5 mA, and the power is 450 W, which is applied to the field of security inspection.

[0031] For those skilled in the art, various corresponding changes and deformations can be given according to the above technical solutions and concepts, and all these changes and deformations should be included within the protection scope of the claims of the present invention.

Claims

1. An X-ray tube with an anode forced cooling structure and a cooling pipeline structure, comprising a cathode, a tube shell, an anode, and a radiator; the cathode is arranged inside the tube shell; one end of the anode is arranged inside the tube shell, and the other end is located outside the tube shell; the radiator is fixed to the other end of the anode; the anode includes an anode cap, an anode target, a target head, and a target body, one end of the target head is fixed in the inner cavity of the other end of the target body, the anode cap covers the other end of the target head and is connected to the target body, and the anode target is embedded in the other end of the target head by vacuum casting; it is characterized in that, It further includes a cooling pipeline, and the cooling pipeline includes a main pipeline, sub-pipelines and an outlet fixed end plate; one end of the main pipeline is communicated with the inlet end of the outlet fixed end plate; there are multiple sub-pipelines, and the bottom of one end of the target head is provided with bottom holes consistent with the number and arrangement of the sub-pipelines; one end of each sub-pipeline is communicated with the main pipeline, and the other end extends into the corresponding bottom hole in a matching manner; the outlet fixed end plate is provided with a number of outlet end through holes; the outlet fixed end plate is fixed to the outer end face of the radiator, and the outer end face of the radiator is provided with a through hole with a diameter larger than the diameter of the inner cavity of the target and communicated with the inner cavity of the target, and the position of the through hole corresponds to the position of the outlet end through hole.

2. The X-ray tube with an anode forced cooling structure and a cooling pipeline structure according to claim 1, characterized in that, The included angle between the end face formed by arranging the bottoms of all the bottom holes of the target head near the anode target and the end face formed by arranging the other ends of all the sub-pipelines and the target face of the anode target is less than 5°.

3. The X-ray tube with an anode forced cooling structure and a cooling pipeline structure according to claim 2, characterized in that, The target face of the anode target is inclined, and the end face formed by arranging the bottoms of all the bottom holes of the target head near the anode target and the end face formed by arranging the other ends of all the sub-pipelines are both inclined.

4. The X-ray tube with an anode forced cooling structure and a cooling pipeline structure according to claim 1, characterized in that, The diameter of the main pipeline is larger than the diameter of the sub-pipelines.

5. The X-ray tube with an anode forced cooling structure and a cooling pipeline structure according to claim 1, characterized in that, The tube shell is made of glass material.

6. The X-ray tube with an anode forced cooling structure and a cooling pipeline structure according to claim 1, characterized in that, The vertical distance between the end face formed by arranging the bottoms of all the bottom holes of the target head near the anode target and the target face of the anode target is 10-12 mm.

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