A helium leak detection fixture for ionization chambers

Abstract

This utility model relates to a helium leak detection fixture for an ionization chamber, belonging to the field of vacuum leak detection technology. The fixture includes a housing, and a detection module, a gas source module, and an external operation module integrated within the housing. The detection module has multiple helium detection chambers of different volumes. Each chamber is connected to a main pipeline via a valved detection branch. The main pipeline has a detection interface for connecting to a helium mass spectrometer. The gas source module includes a built-in air compressor and a helium storage tank. The air compressor is connected to the main pipeline via a valved internal flushing pipeline for internal purging. The external operation module includes an external flushing pipeline and an external helium injection pipeline connected to the air compressor and the helium storage tank, respectively, with external interfaces extending to the housing at their ends. This utility model, through its integrated structural design, integrates multi-specification detection, self-cleaning, and external operation functions, improving leak detection efficiency.

Description

Technical Field

[0001] This utility model belongs to the field of vacuum leak detection technology, specifically relating to a helium leak detection fixture for an ionization chamber. Background Technology

[0002] Helium mass spectrometry leak detection technology boasts extremely high sensitivity and accurate, reliable results, making it widely used in the production and quality control of various components and structural parts with stringent vacuum sealing requirements. Ionization chambers, as key components in high-energy physics and radiation detection, must maintain a high vacuum state internally for extended periods. Even the slightest leak can lead to air infiltration, altering the internal working medium and severely impacting detection accuracy, stability, and even lifespan. Therefore, rigorous and efficient helium sealing testing of ionization chambers is a crucial production step to ensure their performance and reliability.

[0003] Common leak detection fixtures or systems typically provide only a detection chamber of a fixed size and its vacuum interface. This single-chamber design has poor adaptability when dealing with ionization chambers of different sizes and specifications. Since the chamber needs to be evacuated for each test, frequent changes to the ionization chamber or mismatched chamber volumes leading to increased ineffective space will significantly prolong the evacuation time and reduce the overall detection efficiency.

[0004] Furthermore, existing devices have relatively limited functionality, with their purification gas source and critical tracer gas source (helium) typically being independent external devices. This results in the entire leak detection system consisting of multiple dispersed components and complex connecting pipelines, leading to a cluttered on-site layout and low integration. Moreover, this system structure, reliant on multiple external, dispersed devices, makes it inconvenient to move and deploy, hindering its application as a fully functional integrated device in laboratory, production line, or on-site testing settings. Utility Model Content

[0005] To address the aforementioned problems in the prior art, this invention provides a helium leak detection fixture for an ionization chamber. The technical problem to be solved by this invention is achieved through the following technical solution: This utility model provides a helium leak detection fixture for an ionization chamber, comprising: a housing; a detection module including multiple helium detection chambers arranged in parallel within the housing, each helium detection chamber having a different internal volume, each helium detection chamber being connected to a main pipeline via an independent detection branch, the main pipeline having a detection interface for connecting to an external helium mass spectrometer, and each detection branch having a detection control valve; a gas source module, disposed within the housing, including an air compressor and a helium storage tank, the air compressor being connected to the main pipeline via an internal flushing pipeline for introducing flushing gas into the helium detection chambers and the corresponding detection branches and main pipeline; and an external operation module including an external flushing pipeline and an external helium injection pipeline disposed within the housing, the internal flushing pipeline having an internal flushing valve, one end of the external flushing pipeline being close to the air compressor and connected upstream of the internal flushing valve, and the other end being connected to the external flushing interface on the housing; and one end of the external helium injection pipeline being connected to the helium storage tank, and the other end being connected to the external helium injection interface on the housing.

[0006] In one embodiment of this utility model, the internal volumes of the plurality of helium detection chambers are different from each other, and each of the helium detection chambers is provided with an openable and closable sealing end cap.

[0007] In one embodiment of this utility model, a main control valve is provided upstream of the sampling pipeline near the detection interface.

[0008] In one embodiment of this utility model, the external operation module further includes an internal helium branch, one end of which is connected to the external helium injection pipeline and the other end is connected to the main pipeline.

[0009] In one embodiment of this utility model, a backup valve is provided on the internal helium branch. The backup valve is located away from the helium storage tank and is positioned downstream of the connection node between the internal helium branch and the external helium injection pipeline.

[0010] In one embodiment of this utility model, the external operation module further includes at least two expansion interface pipelines, one end of each expansion interface pipeline is provided with an expansion interface, the other end is connected to the summary pipeline, and each expansion interface pipeline is provided with an expansion control valve.

[0011] In one embodiment of this utility model, two expansion interface pipelines are provided, and the expansion interfaces on both expansion interface pipelines are located outside the housing.

[0012] In one embodiment of this utility model, the expansion interface includes a KF25 quick-release flange interface or a G1 / 4 pressure thread interface.

[0013] In one embodiment of this utility model, the external flushing interface is used to connect to an external flushing dust removal gun; the external helium injection interface is used to connect to an external helium injection gun.

[0014] In one embodiment of this utility model, the air compressor and the helium storage tank are respectively fixed to the inner bottom plate of the housing by brackets.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model discloses a helium leak detection fixture for ionization chambers, integrating multiple parallel helium detection chambers, an air compressor and a helium storage tank, as well as external flushing and external helium injection pipelines, into a single housing. The multiple chambers of varying volumes allow the fixture to flexibly adapt to ionization chambers of different sizes. By selecting the most suitable chamber for testing, it effectively reduces wasted space, significantly shortens vacuuming time, and improves detection efficiency. Furthermore, by embedding the gas source within the fixture, it completely avoids the problems of cluttered on-site layout and complex pipeline connections associated with traditional external, distributed equipment. The external flushing and external helium injection interfaces in the external operation module provide convenient physical ports for external purging and cleaning, and external helium injection positioning, making the switching and execution of the leak detection process more efficient and reliable.

[0016] This utility model's helium leak detection fixture for ionization chambers further enhances its adaptability and expandability through expansion interfaces connected to the main pipeline. These expansion interfaces allow the fixture to be easily connected to dedicated detection chambers with larger external dimensions or more specialized structures, not only increasing the functional limit of a single fixture but also enabling it to be integrated as a core unit into more complex detection systems.

[0017] The above description is merely an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] Figure 1 This is a schematic diagram (first axial side view) of a helium leak detection fixture for an ionization chamber provided by an embodiment of the present invention. Figure 2 This is a schematic diagram (second axial side view) of the helium leak detection fixture for an ionization chamber provided in this embodiment of the present invention. Figure 3 This is a schematic diagram (front view) of the helium leak detection fixture for an ionization chamber provided in this embodiment of the present invention. Figure 4This is a schematic diagram of the internal structure of the helium leak detection fixture for the ionization chamber provided in this embodiment of the present invention; Figure 5 This is a schematic diagram of the piping of a helium leak detection fixture for an ionization chamber provided in this embodiment of the present invention.

[0019] Reference numerals: 1-Housing; 2-Helium detection chamber; 21-First detection chamber; 22-Second detection chamber; 23-Third detection chamber; 3-Air compressor; 4-Helium storage tank; 5-Detection interface; 6-First expansion interface; 7-Second expansion interface; 8-External flushing interface; 9-External helium injection interface; 10-Main control valve; 20-First detection control valve; 30-Second detection control valve; 40-Third detection control valve; 50-First expansion control valve; 60-Second expansion control valve; 70-Internal flushing valve; 80-Spare valve. Detailed Implementation

[0020] To further illustrate the technical means and effects adopted by this utility model to achieve its intended purpose, the following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a helium leak detection fixture for an ionization chamber based on this utility model.

[0021] The foregoing and other technical contents, features, and effects of this utility model will be clearly presented in the following detailed description of the specific embodiments with reference to the accompanying drawings. Through the description of the specific embodiments, a more in-depth and specific understanding can be gained of the technical means and effects adopted by this utility model to achieve the intended purpose. However, the accompanying drawings are only provided for reference and illustration and are not intended to limit the technical solution of this utility model.

[0022] Example 1 like Figures 1 to 5 As shown, Figure 1 This is a schematic diagram (first axial side view) of a helium leak detection fixture for an ionization chamber provided by an embodiment of the present invention. Figure 2 This is a schematic diagram (second axial side view) of the helium leak detection fixture for an ionization chamber provided in this embodiment of the present invention. Figure 3 This is a schematic diagram (front view) of the helium leak detection fixture for an ionization chamber provided in this embodiment of the present invention. Figure 4 This is a schematic diagram of the internal structure of the helium leak detection fixture for the ionization chamber provided in this embodiment of the present invention; Figure 5 This is a schematic diagram of the piping of a helium leak detection fixture for an ionization chamber provided in an embodiment of this utility model.

[0023] In this embodiment, a helium leak detection fixture for an ionization chamber includes: a housing 1, and a detection module, a gas source module, and an external operation module disposed within the housing 1.

[0024] Specifically, the detection module includes multiple helium detection chambers 2 arranged side-by-side within the housing 1. Each helium detection chamber 2 has a different internal volume. Each chamber is connected to a central pipeline via an independent detection branch. The central pipeline has a detection interface 5 for connecting to an external helium mass spectrometer. Each detection branch is equipped with a detection control valve to control the opening and closing of its corresponding branch. The gas source module includes an air compressor 3 and a helium storage tank 4. The air compressor 3 is connected to the central pipeline via an internal flushing pipeline. This compressor introduces flushing gas into the helium detection chambers 2 and their corresponding detection branches and the central pipeline. Flushing removes residual helium from the chambers and pipelines, preventing interference with subsequent detections and ensuring the accuracy of the results. The external operation module includes an external flushing pipeline and an external helium injection pipeline located within the housing 1. An internal flushing valve 70 is installed on the internal flushing pipeline to control the connection or isolation between the flushing pipeline and the main pipeline. One end of the external flushing pipeline is located near the air compressor 3 and connected upstream of the internal flushing valve 70; the other end is connected to the external flushing port 8 on the housing 1. This allows the external flushing air path to be independent of the control of the internal flushing valve 70; that is, regardless of whether the internal flushing valve 70 is open or closed, it will not affect the airflow from the air compressor 3 entering the external flushing pipeline. One end of the external helium injection pipeline is connected to the helium storage tank 4, and the other end is connected to the external helium injection port 9 on the housing 1.

[0025] For example, the air compressor 3 and the helium storage tank 4 are respectively fixed to the inner bottom plate of the housing 1 by brackets.

[0026] In one optional implementation, the internal volumes of the multiple helium detection chambers 2 are different, for example, they can be configured in three sizes: small, medium, and large, to accommodate ionization chambers of different sizes. Each helium detection chamber 2 is equipped with an openable and closable sealing end cap. During operation, after placing the ionization chamber to be tested into the selected chamber, closing and locking the end cap completes the sealing. By using multiple sizes of helium detection chambers 2 arranged in parallel and operating independently, while one chamber is performing vacuuming or leak testing on the ionization chamber to be tested, the operator can simultaneously perform clamping and sealing preparation for the next ionization chamber to be tested in another chamber, thereby improving the efficiency of the detection operation.

[0027] In an optional implementation, the external operating module further includes at least two expansion interface pipelines. Each expansion interface pipeline has an expansion interface at one end and is connected to a main pipeline at the other end. Each expansion interface pipeline is also equipped with an expansion control valve for controlling the opening or closing of that expansion interface pipeline. For ionization chambers that are too large or have a special shape to fit into any built-in cavity, an external dedicated detection chamber or adapter fixture can be connected through the expansion interface reserved on the housing 1, thereby expanding the applicability of the tooling.

[0028] For example, there are two expansion interface pipelines, and the expansion interfaces on both expansion interface pipelines are located outside the housing 1.

[0029] Preferably, the expansion interface includes a KF25 quick-release flange interface or a G1 / 4 pressure thread interface.

[0030] In an optional implementation, a main control valve 10 is provided upstream of the main pipeline near the detection interface 5. The main control valve 10 serves as the main switch between the tooling pipeline system and the external helium mass spectrometer. When it is closed, it can isolate the tooling from the external helium mass spectrometer, thereby preventing the gas from directly impacting the external helium mass spectrometer during flushing.

[0031] In an optional implementation, the external operation module also includes an internal helium branch, one end of which is connected to an external helium injection pipeline and the other end is connected to a main pipeline. The internal helium branch allows helium to be directly injected into the vacuumed helium detection chamber 2, thereby filling and leak-detecting the ionization chamber sealed within the chamber.

[0032] In one optional implementation, the external flushing port 8 is used to connect to an external flushing and dust removal gun, allowing for external cleaning of the surface or specific areas of the ionization chamber under test. The external helium injection port 9 is used to connect to an external helium injection gun, allowing helium gas to be injected from the outside into suspected leak locations or critical points within the ionization chamber under test. This enables bidirectional leak detection, accurately identifying leak sites or enhancing the detection of critical points. Similarly, after a single test, the detection site can be flushed with the flushing and dust removal gun to ensure the accuracy of the next test.

[0033] For example, a backup valve 80 is provided on the internal helium branch. The backup valve 80 is located away from the helium storage tank 4 and downstream of the connection node between the internal helium branch and the external helium injection pipeline. The backup valve 80 is used to control the opening and closing of the internal helium branch, but the external helium injection function is not controlled by it, ensuring the independence of the two functions of internal helium filling and external helium injection and avoiding mutual interference during operation.

[0034] Example 2 To enable those skilled in the art to fully understand and implement this utility model, the following supplementary explanation of the specific implementation principle of this utility model is provided in conjunction with a specific application scenario.

[0035] This utility model discloses a highly integrated helium leak detection fixture for ionization chambers. The first detection chamber 21, the second detection chamber 22, and the third detection chamber 23 are all fixedly installed within the housing 1, respectively adapted to accommodate small, medium, and large ionization chambers to be tested, with internal diameters of 108mm, 160mm, and 408mm, respectively. Each chamber is equipped with a quick-opening and closing sealing end cap for easy insertion and removal of the ionization chamber to be tested. The first detection chamber 21 is connected to the main pipeline via a first detection branch and is equipped with a first detection control valve 20. The second detection chamber 22 is connected to the main pipeline via a second detection branch and is equipped with a second detection control valve 30. The third detection chamber 23 is connected to the main pipeline via a third detection branch and is equipped with a third detection control valve 40. The end of the main pipeline is equipped with a detection interface 5 for connecting to an external helium mass spectrometer. A main control valve 10 is located on the main pipeline to control the connection and isolation between the entire fixture and the external helium mass spectrometer. Air compressor 3 is connected to a flushing pipeline, which is equipped with an internal flushing valve 70. Air compressor 3 is also connected to an external flushing interface 8 via an external flushing pipeline, which is used to connect to an external flushing dust removal gun. Helium storage tank 4 is connected to a main pipeline via an internal helium branch line, which is equipped with a spare valve 80. Helium storage tank 4 is also connected to an external helium injection interface 9 via an external helium injection pipeline, which is used to connect to an external helium injection gun. Both the external flushing dust removal gun and the external helium injection gun have independent switches to control the opening and closing of the external flushing pipeline and the external helium injection pipeline, respectively.

[0036] During routine internal helium-filled leak detection, the operator first selects a matching helium detection chamber 2 based on the size of the ionization chamber to be tested. After placing the pre-filled helium-filled ionization chamber into the chamber, the sealing end cap is closed. The corresponding detection control valve and the main control valve 10 are opened, and the chamber is evacuated via a vacuum system connected to an external helium mass spectrometer. If a leak is found in the ionization chamber, the helium gas inside will escape into the chamber and be detected by the helium mass spectrometer. During this process, while one chamber is under vacuum or detection, the operator can simultaneously clamp or disassemble the ionization chambers in other chambers, enabling parallel operations and significantly improving detection efficiency.

[0037] After the initial leak test, when switching to another chamber for leak detection, first, close the main control valve 10 to isolate the internal piping of the tooling from the external helium mass spectrometer. Then, close the detection control valve on the currently used detection branch (such as the first detection control valve 20) to disconnect the chamber from the main pipeline. At this time, the internal flushing valve 70 can be opened to flush and purify the used chamber and piping. Compressed air generated by the air compressor 3 will enter the main pipeline through the internal flushing pipeline and back-purge the corresponding detection branch and helium detection chamber 2 to remove residual helium and ensure the accuracy of the next test. After purging, close the internal flushing valve 70. Finally, open the detection control valve corresponding to the target chamber (such as the second detection control valve 30). At this time, the external vacuum system can begin evacuating the new chamber and proceed with the subsequent leak detection process.

[0038] For ionization chambers where leaks are detected during routine inspections or where precise leak location is required, the external helium injection method can be used. In this case, the ionization chamber is sealed to the detection interface 5 and its interior is evacuated. The external helium injection gun is connected to the external helium injection port 9 on the housing 1, and helium from the built-in helium storage tank 4 is supplied to the gun through the external helium injection pipeline. The operator holds the helium injection gun and scans and sprays suspected leak areas such as welds and interfaces outside the ionization chamber. If the gun is aimed at the leak point, helium will seep into the ionization chamber and be detected instantly by a sensitive helium mass spectrometer, thus achieving precise leak location. After location is complete, an external flushing and dust removal gun can be connected to the external flushing port 8. Using the airflow provided by the external flushing pipeline, which also originates from the air compressor 3 but is independently controlled by the internal flushing valve 70, the helium-sprayed area on the surface of the ionization chamber is purged to remove adhering helium and prevent interference with subsequent operations.

[0039] The tooling of this invention also has good expandability. One expansion interface pipe is connected to a first expansion interface 6, such as a KF25 quick-release flange interface, and is equipped with a first expansion control valve 50; the other expansion interface pipe is connected to a second expansion interface 7, such as a G1 / 4 pressure thread interface, and is equipped with a second expansion control valve 60. By opening the first expansion control valve 50 or the second expansion control valve 60, a larger or structurally unique external detection chamber can be connected to the first expansion interface 6 or the second expansion interface 7, thereby utilizing the air circuit system and air source of this tooling for leak detection.

[0040] When the standby valve 80 is opened, helium from the helium storage tank 4 can be directly introduced into the main pipeline through the internal helium branch line. This is used to perform helium filling and leak detection in vacuum mode on the ionization chamber to be tested placed in the cavity, further enriching the leak detection methods.

[0041] The entire fixture integrates an air compressor 3, a helium storage tank 4, multiple cavities, multiple valves and interfaces into one compact and fully functional unit, enabling efficient operation throughout the entire process from rapid screening and precise positioning to system purification.

[0042] This utility model discloses a helium leak detection fixture for ionization chambers, integrating multiple parallel helium detection chambers, an air compressor and a helium storage tank, as well as external flushing and external helium injection pipelines, into a single housing. The multiple chambers of varying volumes allow the fixture to flexibly adapt to ionization chambers of different sizes. By selecting the most suitable chamber for testing, it effectively reduces wasted space, significantly shortens vacuuming time, and improves detection efficiency. Furthermore, by embedding the gas source within the fixture, it completely avoids the problems of cluttered on-site layout and complex pipeline connections associated with traditional external, distributed equipment. The external flushing and external helium injection interfaces in the external operation module provide convenient physical ports for external purging and cleaning, and external helium injection positioning, making the switching and execution of the leak detection process more efficient and reliable.

[0043] This utility model's helium leak detection fixture for ionization chambers further enhances its adaptability and expandability through expansion interfaces connected to the main pipeline. These expansion interfaces allow the fixture to be easily connected to dedicated detection chambers with larger external dimensions or more specialized structures, not only increasing the functional limit of a single fixture but also enabling it to be integrated as a core unit into more complex detection systems.

[0044] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations are intended to cover non-exclusive inclusion, such that an article or device comprising a list of elements includes not only those elements but also other elements not expressly listed. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device comprising said element. Terms such as "connected" or "linked" are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect. The orientations or positional relationships indicated by terms such as "upper," "lower," "left," and "right" are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention.

[0045] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. A helium leak detection fixture for an ionization chamber, characterized in that, include: case; The detection module includes multiple helium detection chambers arranged in parallel within the housing. The internal volumes of the multiple helium detection chambers are different. Each helium detection chamber is connected to a main pipeline through an independent detection branch. The main pipeline is provided with a detection interface for connecting to an external helium mass spectrometer. Each detection branch is provided with a detection control valve. The gas source module is located inside the housing and includes an air compressor and a helium storage tank. The air compressor is connected to the main pipeline through an internal flushing pipeline and is used to introduce flushing gas into the helium detection chamber and the corresponding detection branch and main pipeline. The external operation module includes an external flushing pipeline and an external helium injection pipeline disposed within the housing. An internal flushing valve is provided on the internal flushing pipeline. One end of the external flushing pipeline is close to the air compressor and connected upstream of the internal flushing valve, and the other end is connected to the external flushing interface on the housing. One end of the external helium injection pipeline is connected to the helium storage tank, and the other end is connected to the external helium injection interface on the housing.

2. The helium leak detection fixture for an ionization chamber according to claim 1, characterized in that, The internal volumes of the multiple helium detection chambers are different from each other, and each of the helium detection chambers is equipped with an openable and closable sealing end cap.

3. The helium leak detection fixture for an ionization chamber according to claim 1, characterized in that, A main control valve is provided upstream of the detection interface on the main pipeline.

4. The helium leak detection fixture for an ionization chamber according to claim 1, characterized in that, The external operation module also includes an internal helium branch, one end of which is connected to the external helium injection pipeline, and the other end is connected to the main pipeline.

5. The helium leak detection fixture for an ionization chamber according to claim 4, characterized in that, A backup valve is provided on the internal helium branch line. The backup valve is located away from the helium storage tank and is situated downstream of the connection node between the internal helium branch line and the external helium injection pipeline.

6. The helium leak detection fixture for an ionization chamber according to claim 1, characterized in that, The external operation module also includes at least two expansion interface pipelines. Each expansion interface pipeline has an expansion interface at one end and is connected to the main pipeline at the other end. Each expansion interface pipeline is also equipped with an expansion control valve.

7. The helium leak detection fixture for an ionization chamber according to claim 6, characterized in that, The expansion interface pipeline is provided with two lines, and the expansion interfaces on both expansion interface pipelines are located outside the housing.

8. The helium leak detection fixture for an ionization chamber according to claim 6, characterized in that, The expansion interface includes a KF25 quick-release flange interface or a G1 / 4 pressure thread interface.

9. The helium leak detection fixture for an ionization chamber according to claim 1, characterized in that, The external flushing port is used to connect to an external flushing and dust removal gun; the external helium injection port is used to connect to an external helium injection gun.

10. The helium leak detection fixture for an ionization chamber according to claim 1, characterized in that, The air compressor and the helium storage tank are respectively fixed to the inner bottom plate of the shell by brackets.

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