A device for detecting the air permeability of a non-woven filter material

Abstract

The utility model relates to non - woven filter material performance detection technical field, and disclose a kind of non - woven filter material air permeability detection device, including detection table, the upper surface center of detection table is equipped with through -hole, the inner side wall of through -hole is slidably connected with downstream pipeline, and the top of downstream pipeline is fixedly connected with sample seat.The utility model is driven sample seat automatic lifting by synchronous electric cylinder, cooperate with the elastic clamping structure of sample pressure ring and spring, replace traditional manual fixing mode, greatly simplify operation procedure, improve installation efficiency;And the elastic pressure of spring can be adjusted according to filter material thickness self -adaptation, realizes the stable clamping of different thickness filter material, solves the problem that traditional device cannot be adapted to diversified thickness sample;Meanwhile, the cooperation of sealing seat and sealing groove and the setting of elastic sealing pad ensure that sample periphery is sealed tightly, avoid airflow leakage to influence detection precision, effectively improve the practicability and detection stability of device.

Description

Technical Field

[0001] This utility model relates to the field of nonwoven filter material performance testing technology, specifically a nonwoven filter material air permeability testing device. Background Technology

[0002] The air permeability of nonwoven filter materials is a core indicator for evaluating their filtration performance and actual effectiveness. Its value directly relates to the applicability and functionality of the filter material in different scenarios: In the medical protective field, the air permeability of nonwoven products such as masks and protective clothing determines the wearer's breathing resistance and long-term wearing comfort; too low air permeability leads to stuffiness and discomfort, while too high permeability may reduce particulate matter interception efficiency. In the air purification field, the air permeability of air conditioning filters and fresh air system filters directly affects air circulation efficiency and equipment energy consumption; insufficient air permeability increases fan load, while excessive permeability may cause unfiltered airflow to short-circuit. In the automotive industry, the air permeability of engine intake filters and cabin air filters needs to be precisely matched with the powertrain's air intake volume and air conditioning airflow; imbalance can lead to power loss or a decline in in-vehicle air quality. Therefore, air permeability testing of nonwoven filter materials is a crucial step in ensuring their reliable application in multiple fields such as medical protection, air purification, and the automotive industry.

[0003] Existing nonwoven filter material permeability testing devices often require manual operation to fix and install filter material samples, which is not only cumbersome and inefficient, but also difficult to meet the testing requirements of filter materials of different thicknesses, thus reducing the practicality of the testing device. Therefore, a nonwoven filter material permeability testing device is proposed. Utility Model Content

[0004] The purpose of this invention is to provide a nonwoven filter material permeability testing device to solve the problems mentioned in the background art, such as the cumbersome operation and low installation efficiency caused by the reliance on manual fixing of filter materials, and the inability to adapt to filter materials of different thicknesses, which reduces practicality.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a non-woven filter material air permeability testing device, comprising a testing platform, a through hole at the center of the upper surface of the testing platform, a downstream pipe slidably connected to the inner wall of the through hole, a sample holder fixedly connected to the top of the downstream pipe, connecting blocks fixedly connected to both sides of the sample holder, mounting holes at both sides of the center of the upper surface of the testing platform, synchronous electric cylinders fixedly connected to the inner walls of the two mounting holes, the output ends of the two synchronous electric cylinders respectively fixedly connected to the bottom center of the two connecting blocks, U-shaped brackets fixedly connected to both sides of the upper surface of the testing platform, connecting holes at the upper surface of the U-shaped brackets, an upstream pipe fixedly connected to the inner wall of the connecting holes, a spring sleeved on the lower part of the outer wall of the upstream pipe, a sealing seat fixedly connected to the lower part of the outer wall of the upstream pipe near the outer side of the spring, a sample pressure ring slidably connected to the inner wall of the sealing seat, and the bottom and top of the spring respectively fixedly connected to the top of the sample pressure ring and the inner top wall of the sealing seat.

[0006] Preferably, the upper surface of the sample holder is provided with a sealing groove, the bottom of the outer side wall of the sealing seat is slidably connected to the inner side wall of the sealing groove, and an elastic sealing gasket is fixedly connected to the outer side of the lower surface of the sealing seat, with the bottom of the elastic sealing gasket adhering to the outer side of the inner bottom wall of the sealing groove.

[0007] Preferably, a sample placement groove is provided at the center of the inner bottom wall of the sealing groove, and the bottom of the outer side wall of the sample pressure ring is slidably connected to the top of the inner side wall of the sample placement groove.

[0008] Preferably, the top of the outer side wall of the sample pressure ring is circumferentially fixedly connected with multiple limiting blocks, the lower part of the inner side wall of the sealing seat is circumferentially provided with multiple limiting grooves, the outer side wall of the limiting blocks is slidably connected to the inner side wall of the limiting grooves, and the inner side wall of the sample pressure ring is slidably connected to the bottom of the outer side wall of the upstream pipe.

[0009] Preferably, a limiting slider is fixedly connected to the center of the two connecting blocks on opposite sides, and a limiting groove is opened on both sides of the U-shaped bracket, with the outer side wall of the limiting slider slidably connected to the inner side wall of the limiting groove.

[0010] Preferably, a fan is fixedly connected to the top of one side of the U-shaped bracket, the air inlet of the upstream pipe is connected to the air outlet of the fan through a connecting pipe, and a honeycomb-shaped flow equalization net is fixedly connected to the top of the inner wall of the upstream pipe.

[0011] Preferably, a differential pressure sensor is installed at the center of the surface of the sample holder, and connection ports are provided on the rear side of the outer walls of the upstream and downstream pipes. The two pressure tapping interfaces of the differential pressure sensor are respectively connected to the inner side walls of the two connection ports through pressure guiding hoses.

[0012] Preferably, a flow regulating valve is installed on the outer wall of the aforementioned connecting pipe.

[0013] Compared with the prior art, the present invention, by adopting the above technical solution, has the following technical effects: This invention utilizes a synchronous electric cylinder to drive the sample holder to automatically rise and fall. Combined with the elastic clamping structure of the sample pressure ring and spring, it replaces the traditional manual fixing method, significantly simplifying the operation process and improving installation efficiency. Furthermore, the elastic pressure of the spring can be adaptively adjusted according to the filter material thickness, achieving stable clamping of filter materials of different thicknesses and solving the problem that traditional devices cannot adapt to samples of diverse thicknesses. Simultaneously, the cooperation between the sealing seat and the sealing groove, along with the setting of the elastic sealing gasket, ensures a tight seal around the sample, preventing air leakage from affecting detection accuracy and effectively improving the practicality and detection stability of the device. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, 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 application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the downstream pipeline and differential pressure sensor structure of this utility model; Figure 3 For the present utility model Figure 2 A schematic diagram of the overall cross-sectional structure; Figure 4 This is a schematic diagram of the sample holder and sample placement groove structure of this utility model; Figure 5 This is a schematic diagram of the sealing seat and sample pressure ring structure of this utility model.

[0016] Explanation of reference numerals in the attached drawings: 11. Detection stage; 12. Through hole; 13. Downstream pipe; 14. Sample holder; 15. Connecting block; 16. Mounting hole; 17. Synchronous electric cylinder; 18. U-shaped bracket; 19. Connecting hole; 20. Upstream pipe; 21. Spring; 22. Sealing seat; 23. Sample pressure ring; 24. Sealing groove; 25. Elastic sealing gasket; 26. Sample placement groove; 27. Limiting block; 28. Limiting groove; 29. ​​Limiting slider; 30. Limiting slide groove; 31. Fan; 32. Connecting pipe; 33. Honeycomb uniform flow mesh; 34. Differential pressure sensor; 35. Connection port; 36. Pressure guiding hose; 37. Flow regulating valve. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce. Example

[0019] In the existing technology, the existing devices rely on manual operation to fix the filter media, which makes the operation cumbersome, the installation efficiency low, and the device cannot be adapted to filter media of different thicknesses, thus reducing its practicality.

[0020] Please see Figures 1-5This utility model provides a technical solution: a non-woven filter material air permeability testing device, including a testing platform 11. A through hole 12 is formed at the center of the upper surface of the testing platform 11. A downstream pipe 13 is slidably connected to the inner wall of the through hole 12. A sample holder 14 is fixedly connected to the top of the downstream pipe 13. Connecting blocks 15 are fixedly connected to both sides of the sample holder 14. Mounting holes 16 are formed on both sides of the center of the upper surface of the testing platform 11. Synchronous electric cylinders 17 are fixedly connected to the inner walls of the two mounting holes 16. The output ends of the two synchronous electric cylinders 17 are respectively fixedly connected to the bottom centers of the two connecting blocks 15. U-shaped brackets 18 are fixedly connected to both sides of the upper surface of 11. A connection hole 19 is opened on the upper surface of the U-shaped bracket 18. An upstream pipe 20 is fixedly connected to the inner wall of the connection hole 19. A spring 21 is sleeved on the lower part of the outer wall of the upstream pipe 20. A sealing seat 22 is fixedly connected to the lower part of the outer wall of the upstream pipe 20 near the outer side of the spring 21. A sample pressure ring 23 is slidably connected to the inner wall of the sealing seat 22. The bottom and top of the spring 21 are fixedly connected to the top of the sample pressure ring 23 and the inner top wall of the sealing seat 22, respectively. The downstream pipe 13 slides inside the through hole 12, thereby ensuring that the downstream pipe 13 slides vertically.

[0021] In one embodiment, specifically: a sealing groove 24 is provided on the upper surface of the sample holder 14, the bottom of the outer side wall of the sealing seat 22 is slidably connected to the inner side wall of the sealing groove 24, and an elastic sealing gasket 25 is fixedly connected to the outer side of the lower surface of the sealing seat 22. The bottom of the elastic sealing gasket 25 is attached to the outer side of the inner bottom wall of the sealing groove 24. The connection between the sample holder 14 and the sealing seat 22 is sealed by the elastic sealing gasket 25, thereby preventing gas leakage.

[0022] In one embodiment, specifically: a sample placement groove 26 is provided at the center of the inner bottom wall of the sealing groove 24, and the bottom of the outer side wall of the sample pressure ring 23 is slidably connected to the top of the inner side wall of the sample placement groove 26, so that the filter material sample can be placed through the sample placement groove 26.

[0023] In one embodiment, specifically: a plurality of limiting blocks 27 are fixedly connected to the top of the outer side wall of the sample pressure ring 23 in a circular shape, and a plurality of limiting grooves 28 are circumferentially formed on the lower part of the inner side wall of the sealing seat 22. The outer side wall of the limiting blocks 27 is slidably connected to the inner side wall of the limiting grooves 28, and the inner side wall of the sample pressure ring 23 is slidably connected to the bottom of the outer side wall of the upstream pipe 20. By sliding the limiting blocks 27 on the outer side wall of the sample pressure ring 23 along the limiting grooves 28 on the inner side wall of the sealing seat 22, it is ensured that the sample pressure ring 23 moves only in the vertical direction, avoiding tilting that would cause uneven force on the sample.

[0024] In one embodiment, specifically: a limiting slider 29 is fixedly connected to the center of the two connecting blocks 15 on opposite sides; a limiting groove 30 is provided on both sides of the U-shaped bracket 18; the outer wall of the limiting slider 29 is slidably connected to the inner wall of the limiting groove 30; by the limiting slider 29 on both sides of the connecting block 15 sliding along the limiting groove 30 of the U-shaped bracket 18, the sample holder 14 is ensured to rise vertically and avoids displacement.

[0025] In one embodiment, specifically: a fan 31 is fixedly connected to the top of one side of the U-shaped bracket 18, and the air inlet of the upstream pipe 20 is connected to the air outlet of the fan 31 through a connecting pipe 32. A honeycomb uniform flow net 33 is fixedly connected to the top of the inner wall of the upstream pipe 20. The honeycomb uniform flow net 33 is composed of densely and uniformly distributed hexagonal or circular holes. When the turbulent airflow passes through these regular channels, it will be forcibly divided into multiple parallel small airflows, the eddies will be eliminated, and the airflow velocity will tend to be uniform in the cross-section, eventually forming a stable laminar flow. This homogenized airflow acts vertically on the surface of the filter material sample, which can ensure that the airflow pressure on each area of ​​the sample is uniform, making the pressure difference on both sides of the filter material detected by the differential pressure sensor 34 more accurate, thereby improving the accuracy of the air permeability calculation (air permeability = flow rate / pressure difference × test area).

[0026] In one embodiment, specifically: a differential pressure sensor 34 is installed at the center of the sample holder 14. Connection ports 35 are provided on the rear outer walls of both the upstream pipe 20 and the downstream pipe 13. The two pressure tapping ports of the differential pressure sensor 34 are connected to the inner walls of the two connection ports 35 via pressure-conducting hoses 36. The differential pressure sensor 34 can capture the pressure difference across the nonwoven filter material sample in real time and accurately, providing core data support for air permeability calculation. Its working logic and overall device coordination are as follows: When the airflow passes through the fixed filter material sample via the upstream pipe 20 and enters the downstream pipe 13, the airflow in the upstream pipe 20 has a relatively high pressure because it does not encounter the resistance of the filter material. After passing through the filter material, the airflow in the downstream pipe 13 has a lower pressure because it overcomes the resistance of the filter material. At this time, the two pressure taps of the differential pressure sensor 34 are connected to the connection port 35 of the upstream pipe 20 (collecting upstream pressure) and the connection port 35 of the downstream pipe 13 (collecting downstream pressure) via the pressure guide hose 36, respectively, to directly measure the pressure difference between the two (i.e., the "pressure drop" of the filter material). The pressure difference is a key indicator for measuring the air permeability of filter media: under the same airflow rate, the better the air permeability of the filter media, the smaller the resistance to airflow and the smaller the pressure difference; conversely, the poor air permeability of the filter media will generate a larger pressure difference. The pressure difference sensor 34 transmits the real-time collected pressure difference data to the control system. Combined with the airflow rate, sample clamping area and other parameters fed back by the flow regulating valve 37, the air permeability parameters of the filter media can be automatically calculated by formula (such as air permeability = flow rate / (pressure difference × test area)), realizing the digitalization and precision of the detection process.

[0027] In one embodiment, specifically: a flow regulating valve 37 is installed on the outer wall of the connecting pipe 32; wherein, the flow regulating valve 37 can change the flow cross-sectional area inside the connecting pipe 32 by rotating the valve disc, thereby adjusting the airflow speed in real time, and thus achieving precise control of the airflow rate entering the upstream pipe 20.

[0028] Working principle or structural principle: Before testing, the operator places the non-woven filter material sample to be tested into the sample placement groove 26 of the sample holder 14, ensuring that the edge of the sample covers the bottom edge of the sample placement groove 26. At this time, the synchronous electric cylinder 17 is in the initial retracted state, the sample holder 14 is in the low position, the bottom of the sealing seat 22 is separated from the sealing groove 24 of the sample holder 14, and the bottom of the sample pressure ring 23 is slightly lower than the bottom of the sealing seat 22 under the natural extension of the spring 21, leaving space for contact with the sample. After the device is started, the output end of the synchronous electric cylinder 17 (working synchronously on both sides) extends, driving the sample holder 14 upward through the connecting block 15. As the sample holder 14 rises, the bottom of the sample pressure ring 23 first contacts the sample surface, and then the sample holder 14 continues to rise. As the sample continues to rise, the sample pressure ring 23 is lifted by the sample, compressing the top spring 21 (the spring force of spring 21 increases with the amount of compression). Finally, the bottom of the sample pressure ring 23 is tightly pressed against the upper surface of the sample. The elastic force of spring 21 adaptively clamps samples of different thicknesses (the spring 21 compresses less for thin samples and more for thick samples, ensuring stable pressure). Simultaneously, the bottom of the outer wall of the sealing seat 22 slides into the sealing groove 24 of the sample seat 14, and the elastic sealing gasket 25 on the lower surface of the sealing seat 22 adheres to the outer side of the bottom wall of the sealing groove 24, forming a seal to prevent air leakage. When the synchronous electric cylinder 17 extends to the preset stroke (which can be adjusted according to the sample thickness via the control system), the sample is completely fixed, and the upper and lower surfaces of the sample are respectively clamped by the sample pressure ring 23 and the sample... The sample is held in place by the bottom of the groove 26, and sealed by the elastic sealing gasket 25 and the sealing groove 24, providing a closed environment for subsequent airflow testing. After the sample is fixed, the blower 31 is started, and the airflow enters the upstream pipe 20 through the connecting pipe 32. At this time, the honeycomb uniform flow mesh 33 on the top of the inner wall of the upstream pipe 20 converts the turbulent airflow sent by the blower 31 into a uniform laminar flow (to avoid pressure detection errors caused by airflow turbulence). The operator adjusts the airflow speed through the flow regulating valve 37 (according to the requirements of the testing standard, such as the specific flow rate specified in GB / T5453) to ensure that the airflow passes stably through the upstream pipe 20. After flowing downward through the upstream pipe 20, the airflow passes vertically through the fixed non-woven filter material sample (the sample is the only channel for airflow, as the outside is sealed), and then enters the... The sample enters and exits through the downstream pipe 13. During this process, the rear side of the outer wall of both the upstream pipe 20 and the downstream pipe 13 is provided with a connection port 35, which is connected to the two pressure taps of the differential pressure sensor 34 through the pressure guide hose 36. The differential pressure sensor 34 monitors the pressure difference (i.e., the pressure drop on both sides of the sample) before and after the airflow passes through the sample in real time and transmits the data to the control system (such as a display screen or data acquisition terminal). After the detection reaches the preset time (set according to the detection standard, such as 20 seconds), the fan 31 stops working, the flow regulating valve 37 closes the airflow, and then the synchronous electric cylinder 17 retracts in the opposite direction, driving the sample seat 14 to move downward. The bottom of the sealing seat 22 gradually separates from the sealing groove 24, the elastic sealing gasket 25 separates from the inner bottom wall of the sealing groove 24, and the outer seal is released.Simultaneously, the sample pressure ring 23, under the restoring force of the spring 21, returns to its original position as the sample holder 14 descends (the spring 21 extends, and the pressure disappears), separating from the sample surface. When the sample holder 14 returns to its initial low position, the operator can directly remove the tested sample from the sample placement groove 26, completing one testing process.

[0029] Core advantages are reflected Throughout the process, the automated lifting of the synchronous electric cylinder replaces manual fixing, the elastic pressure of the spring adapts to samples of different thicknesses (from 0.1mm thin meltblown cloth to 5mm thick composite filter material, it can stably hold them), the sealing structure (elastic sealing gasket + sealing groove) ensures that the airflow passes only through the sample, and the honeycomb uniform flow mesh and differential pressure sensor work together to ensure detection accuracy, solving the problems of cumbersome manual operation, poor adaptability and unstable data of traditional devices.

[0030] In summary, this invention uses a synchronous electric cylinder to drive the sample holder 14 to automatically lift and lower, and with the elastic clamping structure of the sample pressure ring 23 and spring 21, it replaces the traditional manual fixing method, greatly simplifying the operation process and improving installation efficiency. Moreover, the elastic pressure of the spring 21 can be adaptively adjusted according to the thickness of the filter material, achieving stable clamping of filter materials of different thicknesses and solving the problem that traditional devices cannot adapt to samples of diverse thicknesses. At the same time, the cooperation between the sealing seat 22 and the sealing groove 24 and the setting of the elastic sealing gasket 25 ensure that the sample periphery is tightly sealed, avoiding air leakage from affecting the detection accuracy, and effectively improving the practicality and detection stability of the device.

[0031] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this utility model can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in this utility model. In particular, the features described in the various embodiments and / or claims of this utility model can be combined or combined in various ways without departing from the spirit and teachings of this utility model. All such combinations and / or combinations fall within the scope of this utility model.

Claims

1. A nonwoven filter material air permeability detection device, characterized by, The system includes a testing platform (11), with a through hole (12) at the center of its upper surface. A downstream pipe (13) is slidably connected to the inner wall of the through hole (12). A sample holder (14) is fixedly connected to the top of the downstream pipe (13). Connecting blocks (15) are fixedly connected to both sides of the sample holder (14). Mounting holes (16) are provided on both sides of the center of the upper surface of the testing platform (11). Synchronous electric cylinders (17) are fixedly connected to the inner walls of the two mounting holes (16). The output ends of the two synchronous electric cylinders (17) are respectively fixedly connected to the bottom center of the two connecting blocks (15). U-shaped brackets (18) are fixedly connected to both sides of the upper surface of the testing platform (11). A connection hole (19) is opened on the upper surface of the U-shaped bracket (18). An upstream pipe (20) is fixedly connected to the inner side wall of the connection hole (19). A spring (21) is sleeved on the lower part of the outer side wall of the upstream pipe (20). A sealing seat (22) is fixedly connected to the lower part of the outer side wall of the upstream pipe (20) near the outer side of the spring (21). A sample pressure ring (23) is slidably connected to the inner side wall of the sealing seat (22). The bottom and top of the spring (21) are fixedly connected to the top of the sample pressure ring (23) and the inner top wall of the sealing seat (22), respectively.

2. The apparatus for detecting the air permeability of a nonwoven filter material according to claim 1, wherein: The upper surface of the sample holder (14) is provided with a sealing groove (24). The bottom of the outer side wall of the sealing seat (22) is slidably connected to the inner side wall of the sealing groove (24). An elastic sealing gasket (25) is fixedly connected to the outer side of the lower surface of the sealing seat (22). The bottom of the elastic sealing gasket (25) is attached to the outer side of the inner bottom wall of the sealing groove (24).

3. The apparatus according to claim 2, wherein: The inner bottom wall of the sealing groove (24) is provided with a sample placement groove (26), and the bottom of the outer side wall of the sample pressure ring (23) is slidably connected to the top of the inner side wall of the sample placement groove (26).

4. The apparatus for detecting the air permeability of a nonwoven filter material according to claim 1, wherein: The top of the outer side wall of the sample pressure ring (23) is circumferentially fixed with multiple limiting blocks (27), and the lower part of the inner side wall of the sealing seat (22) is circumferentially provided with multiple limiting grooves (28). The outer side wall of the limiting block (27) is slidably connected to the inner side wall of the limiting groove (28), and the inner side wall of the sample pressure ring (23) is slidably connected to the bottom of the outer side wall of the upstream pipe (20).

5. The apparatus for detecting the air permeability of a nonwoven filter material according to claim 1, wherein: Limiting sliders (29) are fixedly connected at the center of the two connecting blocks (15) on opposite sides. Limiting grooves (30) are opened on both sides of the U-shaped bracket (18). The outer side wall of the limiting slider (29) is slidably connected to the inner side wall of the limiting groove (30).

6. The apparatus for detecting the air permeability of a nonwoven filter material according to claim 1, wherein: A fan (31) is fixedly connected to the top of one side of the U-shaped bracket (18). The air inlet of the upstream pipe (20) is connected to the air outlet of the fan (31) through the connecting pipe (32). A honeycomb uniform flow net (33) is fixedly connected to the top of the inner wall of the upstream pipe (20).

7. The apparatus according to claim 1, wherein: A differential pressure sensor (34) is installed at the center of the surface of the sample holder (14). A connection port (35) is provided on the rear side of the outer wall of the upstream pipe (20) and the downstream pipe (13). The two pressure tapping interfaces of the differential pressure sensor (34) are respectively connected to the inner side wall of the two connection ports (35) through pressure guiding hoses (36).

8. The apparatus according to claim 6, wherein: A flow regulating valve (37) is installed on the outer wall of the connecting pipe (32).

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