A film air permeability test fixture

Abstract

The application relates to the field of material performance testing, in particular to a film air permeability testing jig, which comprises a bottom plate, a bearing plate, a clamping mechanism and a vacuum suction monitoring system, the bearing plate is detachably installed on the top of the bottom plate, the bearing plate is provided with a positioning hole, the bottom plate is provided with a filter screen structure at the position corresponding to the positioning hole, a sealing structure for sealing the positioning hole is arranged between the bearing plate and the bottom plate, the clamping mechanism is arranged on the two sides of the bearing plate and used for pressing the film material on the surface of the bearing plate, the bottom of the filter screen is in sealed communication with the vacuum suction monitoring system, the vacuum suction monitoring system extracts air in the positioning hole and monitors air pressure change, and then the air pressure at the bottom of the film material is reduced. The testing jig can improve the efficiency and accuracy of the air permeability test of the film, and effectively avoids the phenomenon that air leakage easily occurs in the existing film air permeability test process, thereby affecting the film air tightness measurement result.

Description

Technical Field

[0001] This application relates to the field of material performance testing, and in particular to a fixture for testing membrane permeability. Background Technology

[0002] In the field of materials performance testing, hydrogen fuel cell technology is developing rapidly. As a core device in hydrogen energy applications, hydrogen fuel cells have demonstrated enormous application potential and development prospects in numerous fields such as electric vehicles, distributed power generation, and energy storage. The proton exchange membrane (PEM), a key component in hydrogen fuel cells, directly determines the battery's ion conduction efficiency, energy conversion efficiency, and overall safety and stability. With the continuous innovation and upgrading of hydrogen fuel cell technology, the quality and performance requirements for PEMs are becoming increasingly stringent. The airtightness of the PEM, as one of the core indicators for evaluating its performance, is crucial for the research, development, production, and quality control of PEMs, providing essential data support. In measuring membrane airtightness, existing technologies typically employ the pressure difference measurement method. This method involves applying different pressures to both sides of the membrane and using pressure sensors and related measuring equipment to monitor changes in the pressure difference over a certain period to infer the membrane's airtightness. In practice, the pressure difference across the membrane is precisely controlled to obtain accurate measurement results. This method is widely used in industrial production and scientific research experiments and is a common means of measuring membrane airtightness. However, existing measurement methods have significant drawbacks in practical applications. When the pressure difference is too large, gaps can easily form between the membrane and the equipment, leading to inaccurate pressure measurements and consequently affecting the assessment of membrane airtightness. Utility Model Content

[0003] In order to improve the efficiency and accuracy of membrane air permeability testing and effectively avoid the situation where air leakage easily occurs in the existing testing process, thus affecting the membrane air tightness measurement results, this application provides a membrane air permeability testing fixture.

[0004] This application provides a membrane permeability testing fixture, including a base plate, a support plate, a clamping mechanism, and a vacuum suction monitoring system. The support plate is detachably mounted on top of the base plate. The support plate has positioning holes, and a filter structure is provided on the base plate at the corresponding position of the positioning holes. A sealing structure for sealing the positioning holes is provided between the support plate and the base plate. The clamping mechanism is respectively disposed on both sides of the support plate to press the membrane material tightly against the surface of the support plate. The bottom of the filter screen is sealed and connected to the vacuum suction monitoring system. The vacuum suction monitoring system extracts air from the positioning holes and monitors air pressure changes, thereby reducing the air pressure at the bottom of the membrane material. By adopting the above technical solution, the support plate can be detachably mounted on top of the base plate, facilitating the assembly and maintenance of the fixture. The positioning holes on the support plate, the corresponding filter structure on the base plate, and the sealing structure between the support plate and the base plate effectively prevent air leakage from the connection between the support plate and the base plate. Meanwhile, the clamping mechanism is located on both sides of the support plate, which can press the membrane material tightly against the surface of the support plate, making the membrane material and the support plate fit tightly together, further reducing the possibility of air leakage. At this time, a sealed space is formed in the positioning hole at the bottom of the membrane material. The fixture has a simple structure, and the bottom of the filter screen is sealed and connected to the vacuum suction monitoring system. When the vacuum suction monitoring system is turned on, it can extract the air in the positioning hole. Due to the combined action of the sealing structure and the clamping mechanism, air leakage is reduced, so the air in the positioning hole can be effectively extracted, thereby reducing the air pressure at the bottom of the membrane material. By monitoring the air pressure change, the air permeability of the membrane material can be accurately inferred based on the rate and magnitude of the air pressure change, providing accurate data support for judging the airtightness of the membrane material, and avoiding the problem of inaccurate pressure measurement caused by gaps between the membrane and the equipment in existing pressure difference measurement methods. Preferably, the sealing structure is an annular sealing gasket, which is set between the contact surfaces of the support plate and the bottom plate. By adopting the above technical solution, the annular sealing gasket is set between the contact surfaces of the support plate and the bottom plate, which can fill the gap between the two. During membrane permeability testing, the vacuum suction monitoring system extracts air from the positioning hole. Without a proper seal, outside air can enter the positioning hole from the contact surface between the support plate and the base plate, interfering with the monitoring of air pressure changes. The annular sealing gasket effectively prevents outside air from entering, avoiding inaccurate pressure measurements due to air leakage, ensuring the accuracy of air pressure change monitoring within the positioning hole, and thus improving the reliability of the membrane permeability test results. Preferably, both the support plate and the base plate are provided with annular grooves that match the contour of the annular sealing gasket. By adopting the above technical solution, with annular grooves matching the contour of the annular sealing gasket on both the support plate and the base plate, the annular sealing gasket can be embedded in the annular groove during installation. This design makes the installation position of the annular sealing gasket more precise and stable, and less prone to displacement or deformation during use.Because the annular sealing gasket is stable in position, it provides a better seal for the positioning hole, effectively preventing air leakage between the contact surfaces of the support plate and the base plate. Preferably, the clamping mechanism includes a pressure rod, a rotational linkage structure, and an abutment block. The pressure rod is rotatably connected to the abutment block via the rotational linkage structure. When the pressure rod is pressed, the rotational linkage structure drives the abutment block to rotate and abut against the surface of the support plate. By adopting the above technical solution, when the pressure rod is pressed, the rotational linkage structure drives the abutment block to rotate. Because the abutment block abuts against the surface of the support plate, this rotational action allows the abutment block to stably press the membrane material against the surface of the support plate. In this way, during membrane permeability testing, the adhesion between the membrane material and the support plate is tighter, reducing the possibility of gaps between the membrane material and the equipment. Preferably, the rotational linkage structure includes a hinge seat and a swing arm. The bottom of the swing arm is rotatably connected to the hinge seat, the top of the swing arm is rotatably connected to the pressure rod, the bottom of the pressure block is rotatably connected to the hinge seat, and the pressure rod is rotatably connected to the top of the pressure block. By adopting the above technical solution, when the pressure rod is pressed, the rotational connections between the bottom of the swing arm and the hinge seat, the top of the swing arm and the pressure rod, the bottom of the pressure block and the hinge seat, and the top of the pressure rod and the pressure block form a movable linkage structure. Under the force of pressing the pressure rod, the swing arm and the pressure block rotate around the hinge seat, thereby driving the abutment block to rotate and abut against the surface of the support plate, thus achieving the function of pressing the membrane material firmly against the surface of the support plate. This rotational linkage structure allows the operation of pressing the pressure rod to be stably and reliably converted into the rotational action of the abutment block. The operation is simple and convenient, and it ensures that the membrane material is stably pressed, avoiding displacement or loosening of the membrane material during testing, thereby improving the accuracy and stability of the membrane permeability test. Preferably, the abutment block is detachably equipped with an elastic abutment joint for abutting the membrane material. By adopting the above technical solution, the abutment block is detachably equipped with an elastic abutment joint. When the membrane material is pressed, the elastic abutment joint contacts the membrane material. Due to its elasticity, it can better adapt to the surface shape of the membrane material, increasing the contact area and thus pressing the membrane material more tightly against the surface of the support plate, improving the sealing performance between the membrane material and the support plate. Simultaneously, the detachable design allows for easy replacement when the elastic abutment joint is worn or damaged, ensuring the long-term stable use of the test fixture, improving its service life and efficiency, and providing a reliable guarantee for accurate testing of membrane permeability. Preferably, the elastic abutment joint is installed on the abutment block via an adjusting nut for adjusting its installation position. By adopting the above technical solution, the elastic abutment joint is installed on the abutment block via an adjusting nut, which allows for adjustment of the installation position of the elastic abutment joint.Because different membrane materials have varying thicknesses and properties, adjusting the installation position of the elastic abutment joint allows it to better adapt to different membrane materials, ensuring effective contact and preventing gaps between the membrane material and the support plate due to improper contact. Preferably, the diameter of the annular sealing gasket is larger than the diameter of the positioning hole. By adopting the above technical solution, since the diameter of the annular sealing gasket is larger than the diameter of the positioning hole, when the support plate and the base plate are installed and fitted, the annular sealing gasket can completely cover the periphery of the positioning hole, effectively preventing air leakage from the positioning hole between the contact surfaces of the support plate and the base plate. This ensures the accuracy of air pressure measurement during the process of the vacuum suction monitoring system extracting air from the positioning hole and monitoring air pressure changes, providing a guarantee for accurate testing of the membrane material's air permeability and improving the performance of the test fixture and the reliability of the test results. Preferably, the base plate has a fluid channel communicating with the filter structure, and the fluid channel is sealed to the vacuum suction monitoring system. By adopting the above technical solution, a fluid channel communicating with the filter structure is set inside the base plate, and this fluid channel is sealed to the vacuum suction monitoring system. This allows the vacuum suction monitoring system to extract air from the positioning holes through the fluid channel and the filter structure during operation. This sealed connection design prevents air leakage and ensures stable air pressure during the extraction of air from the positioning holes. This allows the monitor to more accurately monitor air pressure changes at the bottom of the membrane material, providing more accurate data for membrane permeability testing and improving the accuracy and reliability of the test. Preferably, the vacuum suction monitoring system includes a suction pipe and a monitor. One end of the suction pipe is sealed to the fluid channel, and the other end is sealed to the monitor. When the monitor is activated, the suction pipe extracts air from the positioning holes and monitors air pressure changes at the bottom of the membrane material. By adopting the above technical solution, one end of the suction pipe of the vacuum suction monitoring system is sealed to the fluid channel inside the base plate. The fluid channel is also connected to the filter structure, which corresponds to the positioning hole of the support plate. When the monitor is turned on, the suction pipe can extract air from the positioning hole through the fluid channel and the filter structure, reducing the air pressure at the bottom of the membrane material. Due to the pressure difference between the upper and lower sides of the membrane material, air will permeate through the membrane material and enter the positioning hole. At this time, the monitor can monitor the air pressure change at the bottom of the membrane material. This design can accurately simulate the air permeability environment of the membrane material in actual use and accurately measure the air permeability of the membrane material by monitoring air pressure changes.

[0005] In summary, this application includes at least one of the following beneficial technical effects: 1. A sealing structure is set between the support plate and the base plate. Since the sealing structure fills the gap between the support plate and the base plate, it can effectively prevent gaps from forming between the membrane material and the equipment during the measurement process, avoid pressure leakage caused by gaps, and thus avoid inaccurate pressure measurement, thereby improving the accuracy of membrane airtightness measurement. 2. The clamping mechanism presses the membrane material onto the surface of the support plate. During measurement, the clamping mechanism's pressure rod drives the abutment block to rotate and abut against the surface of the support plate through a rotation linkage structure, thus firmly fixing the membrane material and further ensuring the sealing between the membrane material and the equipment, reducing measurement errors caused by gaps. 3. The vacuum suction monitoring system extracts air from the positioning hole and monitors air pressure changes. When the monitor is turned on, the suction pipe is connected to the filter structure through the fluid channel inside the base plate, extracting air from the positioning hole and reducing the air pressure at the bottom of the membrane material. This method is used to measure the membrane permeability, effectively avoiding the problem of gaps between the membrane and the equipment caused by excessive pressure difference in existing pressure difference measurement methods. It can effectively solve the problem of inaccurate measurement that is common in existing pressure difference measurement methods. Attached Figure Description

[0006] Figure 1 This is a structural diagram of the membrane permeability testing fixture of this application; Figure 2 This is an exploded view of the membrane permeability testing fixture of this application; Figure 3 This is a side view of the membrane permeability testing fixture of this application; Figure 4 yes Figure 3 AA cross-section view.

[0007] Explanation of reference numerals in the attached drawings: 1. Base plate; 2. Bearing plate; 3. Clamping mechanism; 4. Vacuum suction monitoring system; 5. Sealing structure; 11. Filter structure; 12. Fluid channel; 21. Positioning hole; 31. Pressure rod; 32. Rotation linkage structure; 33. Abutment block; 321. Hinge seat; 322. Swing rod; 331. Elastic abutment joint; 332. Adjusting nut; 41. Suction tube; 42. Monitor; 51. Annular sealing gasket; 52. Annular groove. Detailed Implementation

[0008] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0009] This application provides a membrane permeability testing fixture, which is described in the embodiments below. Figure 1 and Figure 2The fixture includes a base plate 1, a support plate 2, a clamping mechanism 3, and a vacuum suction monitoring system 4. The support plate 2 is detachably mounted on top of the base plate 1 and has positioning holes 21. A sealing structure 5 is provided between the support plate 2 and the base plate 1. The clamping mechanism 3 is located on both sides of the support plate 2, pressing the membrane material tightly against its surface so that the membrane material covers the positioning holes 21. The vacuum suction monitoring system 4 removes air from the positioning holes 21 and monitors pressure changes to measure the membrane material's air permeability. This fixture structure is simple and effectively avoids gaps between the membrane and the equipment during membrane air permeability testing, ensuring accurate pressure measurement and thus accurately determining the membrane's airtightness. The sealing structure 5 prevents air leakage from the connection between the support plate 2 and the base plate 1, and the clamping mechanism 3 securely fixes the membrane material to the support plate 2.

[0010] Specifically, in this embodiment, a positioning hole 21 is provided in the middle of the support plate 2. The positioning hole 21 penetrates the upper and lower surfaces of the support plate 2 and is used to place the film material to be tested. The support plate 2 is made of a hard and smooth metal material, such as aluminum alloy. This material has high strength and is not easily deformed, providing stable support for the film material. In this embodiment, the positioning hole 21 is square in shape, but it can also be designed into other shapes such as circles according to actual needs.

[0011] Specifically, in this embodiment, a filter structure 11 is provided on the base plate 1 corresponding to the positioning hole 21. That is, when the membrane material covers the positioning hole 21, the positioning hole 21 at the bottom of the membrane material is a closed space, and air can only flow through the filter structure 11. In this embodiment, the filter structure 11 is made of plastic. Plastic filters can be made of materials such as polypropylene, which are lightweight and low-cost. The function of the filter structure 11 is to prevent membrane material fragments and other impurities from entering the vacuum suction monitoring system 4, ensuring the normal operation of the system.

[0012] Reference Figure 3 and Figure 4 The base plate 1 has a fluid channel 12 that communicates with the filter structure 11. The fluid channel 12 is sealed to the vacuum suction monitoring system 4. The fluid channel 12 is formed by drilling or other processes inside the base plate 1. One end of the fluid channel 12 extends from the upper surface of the base plate 1 to the filter structure 11, and the other end extends from the side wall of the base plate 1 to form an opening. Its function is to connect the filter structure 11 to the vacuum suction monitoring system 4, allowing air to smoothly enter the vacuum suction monitoring system 4 from the positioning hole 21 through the filter structure 11 and the fluid channel 12.

[0013] The sealing structure 5 is an annular sealing gasket 51, which is positioned between the contact surfaces of the support plate 2 and the base plate 1. The annular sealing gasket 51 is typically made of rubber, such as nitrile rubber, which has good elasticity and sealing performance. Both the support plate 2 and the base plate 1 are provided with annular grooves 52 that match the contour of the annular sealing gasket 51. The design of the annular grooves 52 allows for accurate installation of the annular sealing gasket 51, and after the support plate 2 and base plate 1 are installed, the annular sealing gasket 51 can better perform its sealing function, preventing air leakage. Specifically, the diameter of the annular sealing gasket 51 is larger than the diameter of the positioning hole 21, which ensures that the positioning hole 21 is completely sealed, improving the sealing effect.

[0014] Specifically, in this embodiment, the clamping mechanism 3 consists of a pressure rod 31, a rotation linkage structure 32, and an abutment block 33. The pressure rod 31 is rotatably connected to the abutment block 33 via the rotation linkage structure 32. The rotation linkage structure 32 specifically includes a hinge seat 321 and a swing rod 322. The bottom of the swing rod 322 is rotatably connected to the hinge seat 321, and the top of the swing rod 322 is rotatably connected to the pressure rod 31, allowing the pressure rod 31 to swing at a certain angle on the hinge seat 321 via the swing rod 322. The bottom of the abutment block 33 is rotatably connected to the hinge seat 321, and the top of the pressure rod 31 is rotatably connected to the abutment block 33, allowing the pressure block to rotate around its rotation axis relative to the hinge seat 321. When the pressure rod 31 is pressed, the rotation linkage structure 32 drives the abutment block 33 to rotate until it abuts against the surface of the bearing plate 2. The pressure rod 31 is made of metal and has sufficient strength to transmit pressure. The hinge seat 321 and the swing arm 322 are also made of metal to ensure the flexibility and stability of rotation. In this embodiment, there are two clamping mechanisms 3, which are symmetrically arranged at both ends of the support plate 2.

[0015] The bottom of the abutment block 33 is detachably equipped with an elastic abutment joint 331 for abutting the film material. The elastic abutment joint 331 is made of elastic materials such as silicone, which can prevent damage to the film material when pressing it. Furthermore, the elastic abutment joint 331 is installed on the abutment block 33 via an adjusting nut 332 to adjust the installation position of the elastic abutment joint 331. This allows for adjustment according to the actual situation such as the thickness of the film material, ensuring that the elastic abutment joint 331 can effectively press the film material.

[0016] Specifically, in this embodiment, the vacuum suction monitoring system 4 consists of a suction pipe 41 and a monitor 42. The suction pipe 41 is sealed to the fluid channel 12 of the base plate 1. Specifically, one end of the suction pipe 41 is sealed to the open end of the fluid channel 12, and the other end is sealed to the monitor 42. The suction pipe 41 can be made of rubber or plastic, possessing good flexibility and sealing performance. The monitor 42 can monitor the air pressure changes at the bottom of the membrane material in real time. When the monitor 42 is turned on, the suction pipe 41 extracts air from the positioning hole 21 and monitors the air pressure changes at the bottom of the membrane material. By analyzing the air pressure changes, the membrane's air permeability can be accurately determined. Specifically, the monitor 42 has a built-in air pressure sensor, a data acquisition module, and a microprocessor. The air pressure sensor can accurately sense air pressure changes and convert them into electrical signals. The range and accuracy are selected according to requirements to capture minute fluctuations. The data acquisition module is connected to the sensor, receives the electrical signals, performs analog-to-digital conversion, and collects air pressure data at set frequencies to ensure complete and real-time data transmission to the processing unit for analysis. The microprocessor acts as the "brain," receiving digital signals, running algorithms to process and analyze data in real time, judging air pressure trends, and evaluating membrane permeability based on thresholds and models.

[0017] The implementation principle of this embodiment is as follows: When conducting the membrane permeability test, the membrane material to be tested is first placed on the positioning hole 21 of the support plate 2. By adjusting the adjusting nut 332 on the abutment block 33, the position of the elastic abutment 331 is adapted to the thickness of the membrane material. Then, the pressure rod 31 is pressed. The pressure rod 31 drives the abutment block 33 to rotate through the rotation linkage structure 32, so that the elastic abutment 331 abuts against the membrane material, firmly pressing the membrane material onto the surface of the support plate 2, preventing the membrane material from moving during the test and preventing gaps between the membrane and the equipment. When the monitor 42 is turned on, the suction pipe 41 starts to work, drawing out the air in the positioning hole 21 through the fluid channel 12 and filter structure 11 inside the base plate 1. As the air is drawn out, the air pressure at the bottom of the membrane material gradually decreases, and the monitor 42 monitors the change in air pressure at the bottom of the membrane material in real time. Due to the different permeability of the membrane, the speed at which air enters the positioning hole 21 through the membrane is also different, resulting in different rates of change in air pressure at the bottom of the membrane material. By analyzing changes in air pressure, the membrane's permeability can be accurately determined. Compared to existing technologies, this fixture effectively avoids the problem of inaccurate pressure measurements caused by gaps between the membrane and the equipment, improving the accuracy and reliability of measurements and providing more precise data support for membrane research and development, production, and quality control.

[0018] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A fixture for testing membrane air permeability, characterized in that, The system includes a base plate (1), a support plate (2), a clamping mechanism (3), and a vacuum suction monitoring system (4). The support plate (2) is detachably installed on the top of the base plate (1). The support plate (2) is provided with a positioning hole (21). The base plate (1) is provided with a filter structure (11) at the position corresponding to the positioning hole (21). A sealing structure (5) for sealing the positioning hole (21) is provided between the support plate (2) and the base plate (1). The clamping mechanism (3) is respectively provided on both sides of the support plate (2) to press the membrane material onto the surface of the support plate (2). The bottom of the filter structure (11) is sealed and connected to the vacuum suction monitoring system (4). The vacuum suction monitoring system (4) extracts the air in the positioning hole (21) and monitors the air pressure change, thereby reducing the air pressure at the bottom of the membrane material.

2. The membrane permeability testing fixture according to claim 1, characterized in that, The sealing structure (5) is an annular sealing gasket (51), which is disposed between the contact surfaces of the bearing plate (2) and the base plate (1).

3. The membrane permeability testing fixture according to claim 2, characterized in that, Both the bearing plate (2) and the base plate (1) are provided with annular grooves (52) that match the contour of the annular sealing gasket (51).

4. The membrane permeability testing fixture according to claim 1, characterized in that, The clamping mechanism (3) includes a pressure rod (31), a rotation linkage structure (32), and an abutment block (33). The pressure rod (31) is rotatably connected to the abutment block (33) through the rotation linkage structure (32). When the pressure rod (31) is pressed, the rotation linkage structure (32) drives the abutment block (33) to rotate to abut against the surface of the bearing plate (2).

5. The membrane permeability testing fixture according to claim 4, characterized in that, The rotation linkage structure (32) includes a hinge seat (321) and a rocker arm (322). The bottom of the rocker arm (322) is rotatably connected to the hinge seat (321), the top of the rocker arm (322) is rotatably connected to the pressure rod (31), the bottom of the abutment block (33) is rotatably connected to the hinge seat (321), and the pressure rod (31) is rotatably connected to the top of the abutment block (33).

6. The membrane permeability testing fixture according to claim 4, characterized in that, The abutment block (33) is detachably provided with an elastic abutment (331) for abutting the film material.

7. The membrane permeability testing fixture according to claim 6, characterized in that, The elastic abutment (331) is installed on the abutment block (33) by means of an adjusting nut (332) to adjust the installation position of the elastic abutment (331).

8. The membrane permeability testing fixture according to claim 2, characterized in that, The diameter of the annular sealing gasket (51) is larger than the diameter of the positioning hole (21).

9. The membrane permeability testing fixture according to claim 1, characterized in that, The base plate (1) is provided with a fluid channel (12) that communicates with the filter structure (11), and the fluid channel (12) is sealed to the vacuum suction monitoring system (4).

10. The membrane permeability testing fixture according to claim 9, characterized in that, The vacuum suction monitoring system (4) includes a suction pipe (41) and a monitor (42). One end of the suction pipe (41) is sealed to the fluid channel (12), and the other end is sealed to the monitor (42). When the monitor (42) is turned on, the suction pipe (41) extracts the air in the positioning hole (21) and monitors the air pressure change at the bottom of the film material.

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