Testing equipment for high-efficiency air filter

Abstract

The utility model provides test equipment for a high-efficiency air filter, which relates to the field of air filters and comprises a ventilation pipeline, a static pressure box, a detection plate, a support and a suspension assembly. The support is fixedly connected with the detection plate, and the detection plate is provided with an installation position of a to-be-detected air filter. The ventilation pipeline is communicated with an air inlet of the plenum chamber, an air outlet of the plenum chamber is in sealed connection with the detection plate and then is communicated with the mounting position, and the suspension assembly is connected with the ventilation pipeline and the plenum chamber; the detection plate forms a horizontal bearing table through supporting force of the support, and the to-be-detected air filter can be horizontally arranged on the horizontal bearing table. Through the collaborative design of the suspension assembly and the support, the detection plate forms a horizontal bearing table, the horizontal installation working condition is simulated, the test error of the efficient air filter is reduced, and the test efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of air filter technology, and more particularly to a testing device for high-efficiency air filters. Background Technology

[0002] High-efficiency (HEPA) and ultra-high-efficiency (UHEPA) air filters are used to capture particulate matter and suspended particles in the air. They are widely used in the terminal air supply of cleanrooms in industries such as precision machining, biomedicine, semiconductor manufacturing, food processing, and genetic engineering. Their filtration efficiency directly determines whether the cleanliness of the cleanroom and related controlled environments can meet design requirements. With the continuous development of technology, modern scientific experiments and production activities are moving towards more precise processing, miniaturized products, higher purity, and higher reliability. The impact of nanoscale particle contamination is becoming increasingly significant. Against this backdrop, high-performance filters must effectively filter and capture nanoscale particles to prevent them from entering the production line and causing product defects, short circuits, and contamination. Therefore, methods for testing the nanoscale particle filtration efficiency of HEPA and UHEPA filters urgently need to be developed and improved.

[0003] Currently, the main domestic testing standards for high-efficiency air filters are GB / T 13554-2020 "High-Efficiency Air Filters" and GB / T 6165-2021 "Performance Test Methods, Efficiency and Resistance of High-Efficiency Air Filters". In these standards, the counting scan method is used for leak detection of high-efficiency filters, which is the primary test item and directly determines the filter's efficiency rating. However, the standard-specified testing method requires the high-efficiency filter to be vertically fixed to the testing table. In practical applications, air filters used in cleanrooms are mostly placed horizontally at the top of the clean area, which fails to reflect the actual operating conditions of the air filters. Utility Model Content

[0004] The purpose of this application is to provide a testing device for high-efficiency air filters that addresses at least one of the aforementioned existing technical problems, thereby simulating actual usage conditions and improving testing efficiency.

[0005] This application provides a testing device for high-efficiency air filters. The testing device includes a ventilation duct, a static pressure chamber, a test plate, a bracket, and a suspension assembly. The bracket is fixedly connected to the test plate, and the test plate has a mounting position for the air filter to be tested. The ventilation duct is connected to the air inlet of the static pressure chamber, and the air outlet of the static pressure chamber is sealed to the test plate and then connected to the mounting position. The suspension assembly is connected to both the ventilation duct and the static pressure chamber. The test plate forms a horizontal support platform through the support of the bracket, and the air filter to be tested can be placed horizontally on the horizontal support platform.

[0006] In a possible implementation, a lifting mechanism is also included, which is kinetically connected to the bracket to adjust the height of the mounting position.

[0007] Possible implementations may also include multiple downstream particle acquisition devices, downstream particle counting devices, and a three-axis drive device;

[0008] The plurality of downstream particle collection devices are electrically connected to the downstream particle counting device and the three-axis drive device, respectively. The three-axis drive device can output driving force to the plurality of downstream particle collection devices to drive the plurality of downstream particle collection devices to be positioned at a preset position.

[0009] In a possible implementation, a baffle is also included, which is fixedly connected to the detection plate and is disposed on the side of the detection plate near the downstream particle collection device.

[0010] Possible implementations may also include multiple aerosol generating devices, multiple valves, and multiple aerosol discharging devices;

[0011] Multiple aerosol output devices are evenly distributed within the ventilation duct, and the valve is located on the pipeline between the aerosol generating device and the aerosol output device.

[0012] In a possible implementation, a nozzle and a pneumatic baffle mechanism are also included, the pneumatic baffle mechanism being connected to the nozzle and capable of controlling the opening and closing of the nozzle.

[0013] In a possible implementation, the ventilation duct includes a flow equalization section, within which a first fan and a second fan are disposed;

[0014] The first fan is fixedly connected to the inner wall of the ventilation duct, and the airflow direction of the second fan is towards the nozzle.

[0015] One possible implementation includes a flow equalization plate, which is fixedly connected to the inner wall of the ventilation duct.

[0016] In a possible implementation, it may also include an upstream particle collection device, a dilution device, and an upstream particle counting device connected in sequence, wherein the dilution factor of the dilution device is adjustable.

[0017] In a possible implementation, it also includes a host computer and an air outlet device, wherein the air outlet of the air outlet device is connected to the ventilation duct;

[0018] The host computer is communicatively connected to the air outlet device, the upstream particle counting device, the downstream particle counting device, and the three-axis drive device.

[0019] The testing device for high-efficiency air filters provided in this application has the following beneficial effects:

[0020] This application provides a testing device for high-efficiency air filters. The testing device includes a ventilation duct, a static pressure chamber, a test plate, a bracket, and a suspension assembly. The bracket is fixedly connected to the test plate, which has an installation position for the air filter to be tested. The ventilation duct is connected to the air inlet of the static pressure chamber, and the air outlet of the static pressure chamber is sealed to the test plate and then connected to the installation position. The suspension assembly is connected to both the ventilation duct and the static pressure chamber. The test plate forms a horizontal support platform through the support of the bracket, allowing the air filter to be tested to be placed horizontally on the platform. Through the coordinated design of the suspension assembly and the bracket, the test plate forms a horizontal support platform, simulating horizontal installation conditions, reducing testing errors of high-efficiency air filters, and improving testing efficiency. Attached Figure Description

[0021] To more clearly illustrate the technical solution of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the testing equipment in an embodiment of this utility model;

[0023] Figure 2 This is a schematic diagram of the detection plate in an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the downstream particle collection device in an embodiment of this utility model;

[0025] Figure 4 This is a schematic diagram of the structure of the three-axis drive device in an embodiment of this utility model.

[0026] The following is supplementary explanation of the attached figures:

[0027] 1. Air outlet device; 2. Flexible duct; 3. Pre-filter device; 4. Flow equalization plate; 5. Ventilation duct; 6. Aerosol output device; 7. Horizontal adjustment device; 8. Suspension assembly; 9. Valve; 10. First differential pressure gauge; 11. First pressure measuring tube; 12. Aerosol generation device; 13. Nozzle; 14. Pneumatic baffle mechanism; 15. First fan; 16. Second fan; 17. Host computer; 18. Second differential pressure gauge; 19. Second pressure measuring tube; 20. Static pressure box; 21. Upstream particle collection device; 22. Detection plate; 23. Support; 24. Dilution device; 25. Lifting mechanism; 26. Upstream particle counting device; 27. Downstream particle collection device; 28. Air filter to be tested; 29. ​​Baffle; 30. Downstream particle counting device; 31. Three-axis drive device; 311. X-axis motor; 312. Y-axis motor; 313. Z-axis motor. Detailed Implementation

[0028] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0029] As used herein, "an embodiment" or "embodiment" refers to a specific feature, structure, or characteristic that may be included in at least one implementation of this application. In the description of this application, it should be understood that the terms "upper," "lower," "top," "bottom," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0030] The following description, in conjunction with the accompanying drawings, introduces a testing device for high-efficiency air filters provided in the embodiments of this application. This testing device is particularly suitable for application scenarios that test the filtration efficiency of high-efficiency air filters.

[0031] Please refer to Figures 1-4This application provides a testing device for high-efficiency air filters. The testing device includes a ventilation duct 5, a static pressure chamber 20, a test plate 22, a bracket 23, and a suspension assembly 8. The bracket 23 is fixedly connected to the test plate 22, and the test plate has an installation position for the air filter 28 to be tested. The ventilation duct 5 is connected to the air inlet of the static pressure chamber 20, and the air outlet of the static pressure chamber 20 is sealed to the test plate 22 and then connected to the installation position. The suspension assembly 8 is connected to both the ventilation duct 5 and the static pressure chamber 20. The test plate 22 forms a horizontal support platform through the support of the bracket 23, allowing the air filter 28 to be placed horizontally on the platform. Through the coordinated design of the suspension assembly 8 and the bracket 23, the test plate 22 forms a horizontal support platform, simulating horizontal installation conditions, reducing testing errors of the high-efficiency air filter, and improving testing efficiency.

[0032] Understandably, high-efficiency and ultra-high-efficiency air filters are devices used to capture particulate matter and various suspended particles in the air. They are widely used in the terminal air supply of cleanrooms in industries such as precision machining, biomedicine, semiconductor manufacturing, food processing, and genetic engineering. Their filtration efficiency determines whether the cleanliness of the cleanroom and related controlled environment can meet design requirements, and operating resistance directly affects the overall energy consumption of the cleanroom ventilation system. With the continuous development of technology, modern scientific experiments and production activities are moving towards more precise processing, miniaturized products, and higher purity and reliability. The impact of nanoscale particulate contamination is becoming increasingly significant. Therefore, high-performance filters should effectively filter and capture nanoscale particles to prevent them from entering the production line and causing obstacles, short circuits, impurities, and potential defects in products. Thus, methods for testing the nanoscale filtration efficiency of high-efficiency and ultra-high-efficiency filters urgently need to be developed and improved.

[0033] Currently, the main domestic standards for testing high-efficiency air filters are GB / T 13554-2020 "High-Efficiency Air Filters" and GB / T 6165-2021 "Performance Test Methods for High-Efficiency Air Filters: Efficiency and Resistance". Among the various test items specified in the standards, the counting scan method is used for leak detection of high-efficiency filters and is the main test item for high-efficiency filters, directly determining the filtration efficiency classification of high-efficiency filters. The industry's testing method for this item is mainly based on GB / T 6165-2021, but it has two main shortcomings. First, the standard stipulates that the tested high-efficiency filter is vertically fixed on the test stand, but in actual cleanrooms, most air filters are placed horizontally on the top of the clean area, and the test results of the scanning test stand specified in the standard cannot reflect the actual operating conditions of the high-efficiency filter. Second, in the MPPS (Most Penetrating Particle Size) test method specified in the existing high-efficiency air filter standards, the minimum particle size for efficiency testing starts from 100nm, lacking the filtration efficiency of particles below 100nm, and failing to address the key issue of nanoscale particle filtration efficiency that the industry urgently needs. Furthermore, for PTFE HEPA filters, the MPPS (Mean Per Particle Size) is 50–90 nm, unlike typical glass fiber filters which have a particle size exceeding 100 nm. Existing HEPA air filters cannot be tested for nanoparticle filtration efficiency, primarily due to the lack of suitable upstream mixing devices and low upstream particle concentrations. Therefore, it is necessary to design a reliable and efficient air filter scanning test bench based on existing testing methods.

[0034] Specifically, such as Figure 2 As shown, Figure 2 This is a schematic diagram of the detection plate. The size of each mounting position can be adjusted according to the size of the air filter 28 to be tested.

[0035] Specifically, ventilation duct 5 is a wind tunnel, which is a duct that generates artificial airflow to study the aerodynamic effects of airflow over objects. Besides its primary applications in the automotive, aircraft, and missile fields, especially in the design of cruise missiles and air-to-air missiles, wind tunnels are also suitable for air resistance, heat resistance, and pressure resistance testing of buildings, high-speed trains, and ships. The suspension assembly 8 includes a suspension screw and a leveling device 7. In this embodiment, the leveling device 7 is a level adjuster, and the suspension screw is connected to both the ventilation duct 5 and the static pressure chamber 20 via the level adjuster. The suspension screw secures the ventilation duct 5 and the test platform through a hoisting method, saving ground space.

[0036] Specifically, the testing equipment includes an air outlet device 1, a flexible duct 2, and a pre-filter device 3. The flexible duct 2 is connected to the ventilation duct 5. The flexible duct 2 is used to flexibly connect the various components, reduce the transmission of mechanical vibration, and avoid airflow disturbance from affecting the test accuracy. The pre-filter device 3 is a front-end filter. The pre-filter device 3 is used to pre-filter the air entering the ventilation duct 5, remove large particulate impurities, and prevent subsequent equipment from being contaminated.

[0037] Specifically, the testing equipment also includes a first differential pressure gauge 10 and a first pressure measuring tube 11. The first differential pressure gauge 10 is used to measure the pressure difference between the flexible pipe 2 and the flow equalization section, and the first pressure measuring tube 11 is connected to the first differential pressure gauge 10.

[0038] Specifically, the testing equipment also includes a second differential pressure gauge 18 and a second pressure measuring tube 19. The second pressure measuring tube 19 is connected to the second differential pressure gauge 18, which is used to detect the pressure difference between the air pressure inside the static pressure chamber 20 and the atmospheric pressure.

[0039] Specifically, the test plate 22 is located in a clean area with a cleanliness level of ISO CLASS 5, and the air filter to be tested 28 is a high-efficiency or ultra-high-efficiency air filter to be tested. The air filter to be tested 28 is fixed horizontally to simulate actual working conditions.

[0040] Furthermore, the testing equipment also includes a lifting mechanism 25, which is connected to the bracket 23 to adjust the height of the mounting position. In this way, the lifting mechanism 25 can flexibly adjust the height of the mounting position according to the height of the air filter under test, ensuring that the testing equipment can accommodate filters of different sizes and enhancing its versatility. The lifting mechanism 25 can precisely adjust the height of the mounting position to ensure that the air filter is in the preset test position, reducing the impact of positional deviations on the test results.

[0041] Specifically, the lifting mechanism 25 is fixedly connected to the lower surface of the detection plate 22. In this embodiment, the lifting mechanism 25 is a hydraulic lifting platform. The lifting mechanism 25 is used to automatically lift the support 23 and the filter, achieving rapid installation and sealing, and reducing the risks associated with manual operation. In one embodiment, the lifting mechanism 25 is pneumatically connected to the detection plate 22. The lifting mechanism 25 supports the four corners of the support 23 to support the lifting and lowering of the air filter 28 to be tested, reducing the workload and risks associated with manually handling and installing the air filter 28.

[0042] Specifically, sealing gaskets are affixed to all contact parts of the static pressure box 20, bracket 23, air filter 28 to be tested, and test plate 22. After the lifting mechanism 25 rises to the preset height, the sealing gaskets of the contact parts are squeezed to achieve sealing of each component.

[0043] Furthermore, the testing equipment also includes multiple downstream particle collection devices 27, a downstream particle counting device 30, and a three-axis drive device 31. The multiple downstream particle collection devices 27 are electrically connected to the downstream particle counting device 30 and the three-axis drive device 31, respectively. The three-axis drive device 31 can output driving force to the multiple downstream particle collection devices 27 to drive them to a preset position. In this way, the multiple downstream particle collection devices 27 can work in parallel, improving testing efficiency and ensuring that particle concentration data can be acquired in real time at multiple locations or sampling points. The downstream particle counting device 30 can accurately record the number and distribution of particles at each collection point, thereby improving the accuracy of the particle concentration data.

[0044] Specifically, the three-axis drive device 31 is a servo three-axis drive mechanism, which includes an X-axis motor 311, a Y-axis motor 312, and a Z-axis motor 313. In this embodiment, the multiple downstream particle collection devices 27 include three downstream isodynamic sampling heads. The three probes are used to simultaneously collect downstream aerosol samples, shortening the testing time and improving efficiency. The control device can control the servo three-axis drive mechanism to automatically operate according to a predetermined program, driving the three downstream isodynamic sampling heads to scan the downstream particle count of the air filter 28 to be tested along a set route. The X-axis motor 311 controls the downstream isodynamic sampling head to move along the X-axis, the Y-axis motor 312 controls the downstream isodynamic sampling head to move along the Y-axis, and the Z-axis motor 313 controls the downstream isodynamic sampling head to move along the Z-axis. This mechanical approach makes the test results more accurate and stable.

[0045] Furthermore, the testing equipment also includes a baffle 29, which is fixedly connected to the detection plate 22 and is positioned on the side of the detection plate 22 near the downstream particle collection device 27. In this way, the baffle 29 helps reduce interference from other factors on the downstream particle collection device 27, preventing irregular diffusion or displacement of particles during flow, ensuring that the particle collection device can accurately collect particles from the filtered airflow, and contributing to improved stability and reliability of the test results.

[0046] In one possible implementation, the size of the baffle 29 can be determined based on the size of the detection plate 22 and the structural requirements of the particle collection device.

[0047] Alternatively, the baffle 29 and the detection plate 22 can be connected by bolts, welding, or slots.

[0048] Furthermore, the testing equipment also includes multiple aerosol generating devices 12, multiple valves 9, and multiple aerosol discharging devices 6. The multiple aerosol discharging devices 6 are evenly distributed within the outlet duct, and the valves 9 are located on the pipeline between the aerosol generating devices 12 and the aerosol discharging devices 6. This even distribution of multiple aerosol discharging devices 6 within the outlet duct ensures uniform aerosol distribution throughout the entire pipeline system. This maintains a consistent aerosol concentration throughout the testing area, helping to simulate the real-world airflow and particle distribution in practical applications, thereby improving the accuracy of the test.

[0049] Specifically, the aerosol generating device 12 is an aerosol generator that can generate aerosol particles of specific types and concentrations, such as NaCl and DEHS, to simulate pollutants. The multiple valves 9 are multiple gas valves that are used to control the on / off state and flow rate of the aerosol generator, thereby enabling the switching of multiple aerosol types.

[0050] Specifically, multiple valves 9 can precisely control the aerosol flow rate and concentration of each aerosol output device 6. Testers can adjust the aerosol concentration as needed to conduct filtration efficiency tests under different conditions and meet various test requirements.

[0051] Specifically, the aerosol output device 6 is a multi-point generating nozzle, which can uniformly spray aerosol particles at multiple locations to ensure uniform distribution of upstream aerosols.

[0052] Furthermore, the testing equipment also includes a nozzle 13 and a pneumatic baffle mechanism 14. The pneumatic baffle mechanism 14 is connected to the nozzle 13 and can control the opening and closing of the nozzle 13. In this way, the pneumatic baffle mechanism 14 can precisely adjust the opening and closing of the nozzle 13 to achieve accurate measurement under a wide range of airflow.

[0053] Specifically, the pneumatic baffle mechanism 14 includes a telescopic rotary cylinder and a nozzle baffle. In the embodiments of this specification, the test equipment includes multiple nozzles, and the opening and closing of the multiple nozzles are independently controlled by different nozzle baffles and cylinders, so as to use different combinations of nozzles for testing according to the test air volume, thereby reducing measurement errors.

[0054] Furthermore, the ventilation duct 5 includes a flow equalization section, in which a first fan 15 and a second fan 16 are installed;

[0055] The first fan 15 is fixedly connected to the inner wall of the ventilation duct 5, and the airflow direction of the second fan 16 is towards the nozzle 13. In this way, the flow equalization section can avoid test errors caused by uneven airflow, and the synergistic effect of the first fan 15 and the second fan 16 can ensure that the airflow flows evenly in the duct, thereby providing stable and consistent airflow conditions for the filter and ensuring the accuracy of the test results.

[0056] Specifically, the first fan 15 is an oscillating crossflow fan, and the second fan 16 is a stationary counterflow fan. The oscillating crossflow fan is a fan that can oscillate laterally in the duct. The oscillating crossflow fan can ensure that the air can spread widely in the duct. The function of the stationary counterflow fan is to generate a relatively stable airflow through stationary counterflow. This design can help the nozzle 13 output stably, avoid uneven airflow or the generation of local eddies, and ensure that the air volume at the nozzle 13 is uniform.

[0057] Furthermore, the testing equipment also includes a flow equalization plate 4, which is fixedly connected to the inner wall of the ventilation duct 5. In this way, the flow equalization plate 4 can eliminate turbulence and non-uniformity in the airflow, ensuring that the airflow smoothly transitions to the filter or other test areas, which helps to provide stable and consistent airflow conditions for filter testing and avoids test errors caused by non-uniform airflow.

[0058] Specifically, in this embodiment, the ventilation duct 5 is provided with multiple flow equalization plates 4. The first flow equalization plate is disposed between the pre-filter and the flow equalization section, and the second and third flow equalization plates are disposed between the flow equalization section and the static pressure box 20. In this embodiment, the flow equalization plates 4 play the role of uniformly distributing airflow.

[0059] Furthermore, the testing equipment also includes an upstream particle collection device 21, a dilution device 24, and an upstream particle counting device 26 connected in sequence. The dilution factor of the dilution device 24 is adjustable. In this way, the adjustable dilution factor of the dilution device 24 allows the tester to precisely control the concentration of particles in the airflow flowing into the upstream particle collection device 21, which can meet the needs of various testing conditions.

[0060] Specifically, the upstream particle sampling device 21 is used to collect aerosol samples upstream of the filter, ensuring that the sampling speed is consistent with the airflow speed to avoid sampling deviation. The dilution device 24 is used to adjust the upstream aerosol concentration to prevent the particle counter from saturating due to excessively high concentration. The upstream particle counting device 26 is an upstream particle counter used to detect the number and particle size distribution of upstream aerosol particles in real time. The dilution factor of the dilution device 24 is continuously adjustable within a certain range, ensuring that the concentration of the tested aerosol particles is always lower than the saturation concentration of the upstream particle counter.

[0061] Furthermore, the testing equipment also includes a host computer 17 and an air outlet device 1, the air outlet of which is connected to the ventilation duct 5.

[0062] The host computer 17 is communicatively connected to the air outlet device 1, the upstream particle counting device 26, the downstream particle counting device 30, and the three-axis drive device 31. In this way, the host computer 17 can centrally control the testing process of the testing device. Testing personnel can perform unified management and operation through the host computer 17, including adjusting the air speed of the air outlet device 1, starting and stopping the particle counting device, and controlling the three-axis drive device 31, thereby improving the automation level of the testing process, reducing manual intervention, and enhancing efficiency and accuracy.

[0063] Specifically, in this embodiment, the air outlet device 1 is a variable frequency fan, and the host computer 17 includes a central control system. The host computer 17 is used to integrate automated testing programs and can also control the variable frequency fan, sampling head, data recording and analysis, and output particle distribution cloud map. The host computer 17 contains a complete set of automated testing programs that meet standard requirements. The host computer 17 realizes mode switching for different air volume points through preset programs, controls the opening and closing of nozzles 13 with different flow rates through a rotary telescopic cylinder according to the air volume and parameters of a single nozzle 13, automatically records raw data and outputs particle number distribution cloud map, classifies filter filtration efficiency levels through data processing, and accurately locates the leak point of the air filter 28 to be tested.

[0064] Specifically, the connection between the host computer 17 and the three-axis drive device 31 makes the actions during the testing process more coordinated and synchronized. The control of the three-axis drive device 31 can be adjusted according to the instructions of the host computer 17, ensuring that each part of the testing equipment can work in the correct sequence. For example, the host computer 17 can simultaneously adjust the wind speed and particle concentration when adjusting the filter position, thereby more accurately evaluating the filter performance.

[0065] The following describes the working process of the testing device for air filters in the embodiments of this application, with reference to specific application scenarios:

[0066] S1. Select the test plate 22 according to the size of the air filter to be tested, and fix the air filter to be tested 28 and the test plate 22 on the bracket 23 to ensure horizontal installation;

[0067] S2, turn on the host computer 17, input the air outlet size of the air filter 28 to be tested, set one or more test air volume points, and the host computer 17 software automatically plans the scanning speed and path of the downstream particle collection device 27 according to the standard test method.

[0068] S3, control the lifting mechanism 25 to rise, so that the bracket 23 and the static pressure box 20 are tightly fitted to form a sealed environment, raise the downstream particle collection device 27 to a distance of 2cm from the air outlet of the filter, and position it at the scanning origin.

[0069] S4, the variable frequency fan adjusts the speed according to the set air volume, the rotary telescopic cylinder controls the opening and closing of the nozzle 13 to match different air volume requirements, the first differential pressure gauge 10 monitors and feeds back the air volume data in real time, and the gas enters the ventilation duct 5 after being purified by the pre-filter device 3 to form a clean airflow.

[0070] S5, the aerosol generating device 12 is started. The clean airflow carries aerosol particles into the ventilation duct 5. The aerosol passes through each flow equalization plate 4 and the oscillating crossflow fan in sequence, forming a stable and uniform unidirectional airflow in the ventilation duct 5.

[0071] S6, the upstream particle collection device 21 and the downstream particle collection device 27 are started synchronously. The upstream particle collection device 21 records the number and particle size distribution of upstream particles in real time, and the downstream particle collection device 27 records the downstream particle data. The servo triaxial testing mechanism drives the downstream particle collection device 27 to scan the downstream surface of the air filter 28 to be tested along a preset path and collect data point by point.

[0072] S7. After the test is completed, the host computer 17 automatically generates a particle distribution cloud map, marks the location of the leak, and calculates the filtration efficiency and classifies the filtration level based on the comparison of the number of particles upstream and downstream.

[0073] S8. If multiple air volume points are preset, the host computer 17 will automatically switch to the next air volume point and repeat steps S4 to S7. After all air volume points are tested, a comprehensive test report will be output.

[0074] S9, turn off the variable frequency fan and aerosol generating device 12, lower the lifting mechanism 25, remove the air filter 28 to be tested, clean the ventilation duct 5 and each collection device to ensure that there are no residual particles.

[0075] The following describes specific embodiments of this application based on the above technical solution.

[0076] Example 1

[0077] See Figures 1-4Example 1 provides a testing device for high-efficiency air filters. The testing device includes a ventilation duct 5, a static pressure chamber 20, a test plate 22, a bracket 23, and a suspension assembly 8. The bracket 23 is fixedly connected to the test plate 22, and the test plate has an installation position for the air filter 28 to be tested. The ventilation duct 5 is connected to the air inlet of the static pressure chamber 20, and the air outlet of the static pressure chamber 20 is sealed to the test plate 22 and then connected to the installation position. The suspension assembly 8 is connected to both the ventilation duct 5 and the static pressure chamber 20. The test plate 22 forms a horizontal support platform through the support force of the bracket 23, allowing the air filter 28 to be tested to be placed horizontally on the horizontal support platform. The test plate 22 is located in a clean area with an ISOCLASS 5 cleanliness level. The air filter 28 to be tested is a high-efficiency or ultra-high-efficiency air filter, and the air filter 28 is horizontally fixed to simulate actual working conditions.

[0078] The testing equipment also includes a lifting mechanism 25, which is connected to the support 23 to adjust the height of the mounting position. The lifting mechanism 25 is fixedly connected to the lower surface of the detection plate 22. The lifting mechanism 25 is a hydraulic lifting platform. Sealing gaskets are affixed to all contact parts of the static pressure box 20, the support 23, the air filter to be tested 28, and the detection plate 22. After the lifting mechanism 25 rises to the preset height, the sealing gaskets of the contact parts are squeezed to seal each component. The testing equipment also includes multiple downstream particle collection devices 27, a downstream particle counting device 30, and a three-axis drive device 31. The multiple downstream particle collection devices 27 are electrically connected to the downstream particle counting device 30 and the three-axis drive device 31, respectively. The three-axis drive device 31 can output driving force to the multiple downstream particle collection devices 27 to drive the multiple downstream particle collection devices 27 to be positioned at the preset position. The three-axis drive device 31 is a servo three-axis drive mechanism, which includes an X-axis motor 311, a Y-axis motor 312, and a Z-axis motor 313. The testing equipment also includes a baffle 29, which is fixedly connected to the detection plate 22 and is located on the side of the detection plate 22 near the downstream particle collection device 27.

[0079] The testing equipment also includes multiple aerosol generators, multiple valves 9, and multiple aerosol output devices 6. The multiple aerosol output devices 6 are evenly distributed within the air outlet duct, and the valves 9 are located on the pipeline between the aerosol generators and the aerosol output devices 6. The testing equipment also includes nozzles 13 and a pneumatic baffle mechanism 14. The pneumatic baffle mechanism 14 is connected to the nozzles 13 and can control the opening and closing of the nozzles 13. The ventilation duct 5 includes a flow equalization section, within which a first fan 15 and a second fan 16 are installed. The first fan 15 is fixedly connected to the inner wall of the ventilation duct 5, and the second fan 16 directs the airflow towards the nozzles 13. The first fan 15 is an oscillating crossflow fan, and the second fan 16 is a stationary counterflow fan.

[0080] The testing equipment also includes a flow equalization plate 4, which is fixedly connected to the inner wall of the ventilation duct 5. The ventilation duct 5 is equipped with multiple flow equalization plates 4. The first flow equalization plate is located between the pre-filtration device and the flow equalization section, and the second and third flow equalization plates are located between the flow equalization section and the static pressure chamber 20. The testing equipment also includes an upstream particle collection device 21, a dilution device 24, and an upstream particle counting device 26 connected in sequence. The dilution ratio of the dilution device 24 is adjustable.

[0081] Example 2

[0082] The difference between Example 2 and Example 1 is that the testing equipment also includes a host computer 17 and an air outlet device 1. The air outlet of the air outlet device 1 is connected to the ventilation duct 5. The host computer 17 is communicatively connected to the air outlet device 1, the upstream particle counting device 26, the downstream particle counting device 30, and the three-axis drive device 31. The air outlet device 1 is a variable frequency fan. The host computer 17 includes a central control system. The host computer 17 is used to integrate automated testing programs and can also control the variable frequency fan, sampling head, data recording and analysis, and output particle distribution cloud maps. The host computer 17 contains a complete set of automated testing programs that meet the standard requirements.

[0083] The host computer 17 switches between modes for different air volume points through a preset program. Based on the air volume and the parameters of a single nozzle 13, it controls the opening and closing of nozzles 13 with different flow rates through a rotary telescopic cylinder. It automatically records the raw data and outputs a particle number distribution cloud map. Through data processing, it classifies the filter efficiency level and accurately locates the leak point of the air filter 28 to be tested.

[0084] The above-disclosed embodiments are merely several preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A testing device for high-efficiency air filters, characterized in that, The testing equipment includes a ventilation duct (5), a static pressure chamber (20), a test plate (22), a bracket (23), and a suspension assembly (8); The bracket (23) is fixedly connected to the detection plate (22), and the detection plate (22) is provided with an installation position for the air filter (28) to be tested; The ventilation duct (5) is connected to the air inlet of the static pressure box (20), and the air outlet of the static pressure box (20) is connected to the installation position after being sealed and connected to the detection plate (22). The suspension assembly (8) is connected to the ventilation duct (5) and the static pressure box (20) respectively. The detection plate (22) forms a horizontal support platform through the support force of the bracket (23), and the air filter (28) to be tested can be placed horizontally on the horizontal support platform.

2. The testing equipment according to claim 1, characterized in that, It also includes a lifting mechanism (25), which is connected to the bracket (23) to adjust the height of the mounting position.

3. The testing equipment according to claim 1, characterized in that, It also includes multiple downstream particle collection devices (27), downstream particle counting devices (30) and a three-axis drive device (31). The plurality of downstream particle collection devices (27) are electrically connected to the downstream particle counting device (30) and the three-axis drive device (31), respectively. The three-axis drive device (31) can output driving force to the plurality of downstream particle collection devices (27) to drive the plurality of downstream particle collection devices (27) to be located at a preset position.

4. The testing equipment according to claim 3, characterized in that, It also includes a baffle (29), which is fixedly connected to the detection plate (22) and is disposed on the side of the detection plate (22) near the downstream particle collection device (27).

5. The testing equipment according to any one of claims 1-4, characterized in that, It also includes multiple aerosol generating devices (12), multiple valves (9) and multiple aerosol output devices (6). Multiple aerosol output devices (6) are evenly arranged in the ventilation duct (5), and the valve (9) is installed on the pipeline between the aerosol generating device (12) and the aerosol output device (6).

6. The testing equipment according to any one of claims 1-4, characterized in that, It also includes a nozzle (13) and a pneumatic baffle mechanism (14), the pneumatic baffle mechanism (14) being connected to the nozzle (13), and the pneumatic baffle mechanism (14) being able to control the opening and closing of the nozzle (13).

7. The testing equipment according to claim 6, characterized in that, The ventilation duct (5) includes a flow equalization section, in which a first fan (15) and a second fan (16) are provided. The first fan (15) is fixedly connected to the inner wall of the ventilation duct (5), and the airflow direction of the second fan (16) is towards the nozzle (13).

8. The testing equipment according to any one of claims 1-4, characterized in that, It also includes a flow equalization plate (4), which is fixedly connected to the inner wall of the ventilation duct (5).

9. The testing equipment according to any one of claims 1-4, characterized in that, It also includes an upstream particle collection device (21), a dilution device (24) and an upstream particle counting device (26) connected in sequence, wherein the dilution factor of the dilution device (24) is adjustable.

10. The testing equipment according to any one of claims 1-4, characterized in that, It also includes a host computer (17) and an air outlet device (1), the air outlet of which is connected to the ventilation duct (5); The host computer (17) is communicatively connected to the air outlet device (1), the upstream particle counting device (26), the downstream particle counting device (30), and the three-axis drive device (31).

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