Automatic membrane changing device for particulate matter sampling and membrane changing method
By designing an automatic membrane changer for particulate matter sampling with a filter membrane drive and a pressing sample injection mechanism, the problems of large equipment size and susceptibility to environmental influences in existing technologies have been solved. This achieves automatic membrane changing, reduces operation and maintenance costs and mechanical failures, and has strong adaptability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-05
- Publication Date
- 2026-04-07
AI Technical Summary
Existing particulate matter sampling membrane exchangers are large in size and have complex mechanisms. They are greatly affected by environmental factors in outdoor environments and are prone to mechanical problems.
An automatic membrane changer for particulate matter sampling was designed, comprising a filter membrane transmission mechanism and a pressing and injection mechanism. Automatic membrane changing is achieved by using a geared motor to drive the filter membrane assembly to rotate and the pressing block to press. The gas channel is integrated on the lifting drive assembly, simplifying the sampling gas path structure.
It achieves automatic membrane replacement, extends the equipment operation and maintenance cycle, reduces operation and maintenance costs, and is compact in size, highly adaptable, compatible with a variety of equipment, reduces mechanical failures, and lowers the probability of failure.
Smart Images
Figure CN121797014A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of particulate matter sampling and testing technology, and specifically relates to an automatic membrane changer and membrane change method for particulate matter sampling. Background Technology
[0002] Most existing particulate matter sampling membrane changers have a bulky enclosure containing a large automated slide and other moving parts. During membrane replacement, the membrane is transported to a designated position via the large slide, and then a conveyor device, such as a conveyor belt or slide, transports the membrane to the inlet / outlet position for air intake. After air intake is complete, the used membrane is returned to the large slide via the conveyor device. Once back on the slide, it is raised one position for the next sample intake. However, these existing particulate matter sampling membrane changers are large and complex, making them highly susceptible to environmental factors in outdoor environments, such as high temperatures or dust, which can cause various mechanical problems. Summary of the Invention
[0003] Based on the above analysis, the present invention aims to provide an automatic membrane changer and membrane changing method for particulate matter sampling, in order to solve the problems of large size and complex mechanism of existing particulate matter sampling membrane changers, which are greatly affected by environmental factors in outdoor environments.
[0004] The objective of this invention is achieved as follows: On the one hand, an automatic membrane changer for particulate matter sampling is provided, comprising: The filter membrane transmission mechanism includes a membrane tray, a rotation drive assembly, a membrane top plate, and a membrane bottom plate. Multiple filter membrane assemblies are detachably mounted on the membrane tray. The rotation drive assembly is configured to drive the membrane tray to rotate, causing the multiple filter membrane assemblies to rotate sequentially to the sampling position. The membrane top plate and the membrane bottom plate are fixedly connected, and the membrane tray is rotatably positioned within the space between the membrane top plate and the membrane bottom plate. The compression injection mechanism includes an upper membrane pressure block, a lower membrane pressure block, and a lifting drive assembly. The upper membrane pressure block is located directly above the lower membrane pressure block and connected to the top plate of the membrane carrier. The filter membrane assembly at the sampling position is located between the upper and lower membrane pressure blocks. The lifting drive assembly is configured to drive the lower membrane pressure block to rise and fall. The lifting drive assembly has a built-in air passage one, the membrane drag lower pressure block has an air passage two, and the membrane drag upper pressure block has an air passage three; air passage one, air passage two and air passage three can be connected to form a sealed sampling air passage when the lifting drive assembly drives the membrane drag lower pressure block to rise.
[0005] Furthermore, airway one, airway two, and airway three are arranged coaxially and vertically.
[0006] Furthermore, the sampling gas path has a sampling gas inlet and a sampling gas outlet. The top port of gas path three is the sampling gas inlet, and the bottom port of gas path one is the sampling gas outlet.
[0007] Furthermore, the drive assembly includes a second geared motor, a push rod gear, and a push rod rack. The push rod rack is vertically adjustable and has a hollow structure. The hollow channel of the push rod rack is an air passage. The top of the push rod rack is sealed to the lower pressure block of the diaphragm. The output shaft of the second geared motor is equipped with a push rod gear, which meshes with the teeth on the outer wall of the push rod rack. The second geared motor drives the push rod gear to rotate, thereby raising and lowering the push rod rack.
[0008] Furthermore, the drive assembly also includes a pressing block and a linear bearing, with the push rod rack mounted on the pressing block via the linear bearing; a second geared motor is fixedly mounted on the pressing block, and the film base plate is fixedly mounted on the pressing block via a connecting seat.
[0009] Furthermore, there are two linear bearings, which are located at the upper and lower parts of the push rod rack and on the upper and lower sides of the push rod gear.
[0010] Furthermore, the filter membrane assembly includes a membrane carrier and a filter membrane disposed on the membrane carrier, and the membrane carrier tray is provided with a plurality of holes for placing the membrane carrier.
[0011] Furthermore, the rotation drive assembly includes a geared motor, which is mounted on the film substrate and connected to the tray shaft via a coupling. The upper part of the tray shaft is fixedly connected to the center of the film tray.
[0012] Furthermore, guide rollers are provided between the film tray and the bottom plate of the film tray, and between the film tray and the top plate of the film tray. The guide rollers are configured to limit the vertical floating of the film tray.
[0013] Furthermore, a photoelectric sensor is provided on the top plate of the carrier membrane, and multiple light-shielding plates are provided on the carrier membrane tray at the positions corresponding to the filter membrane assembly. The light-shielding plates can rotate with the carrier membrane tray. When the light-shielding plate rotates to the position where the photoelectric sensor is blocked, the filter membrane assembly at the corresponding position rotates into place, and the carrier membrane tray stops rotating.
[0014] Furthermore, a first sealing ring is provided between the bottom end face of the upper pressure block of the membrane carrier and the upper surface of the membrane carrier, a second sealing ring is provided between the top end face of the lower pressure block of the membrane carrier and the lower surface of the membrane carrier, and the top end of the push rod rack is sealed to the lower pressure block of the membrane carrier through a third sealing ring.
[0015] Furthermore, the automatic membrane changer for particulate matter sampling also includes a second roller, a wheel frame, a top rod, a connector, a connecting plate, and an elastic element. The second roller is connected to the wheel frame and can rotate relative to it. Both the second roller and the wheel frame are located between the film carrier tray and the film carrier top plate. The top rod is perpendicular to the film carrier top plate and passes through the upper and lower end faces of the film carrier top plate. The top rod can move up and down relative to the film carrier top plate. The lower end of the top rod is connected to the wheel frame. The top rod is located on the line connecting the rotation center of the film carrier tray and the pressure block on the film carrier. The connector is fixed to the film carrier top plate. Above, the connecting plate has a first end connected to the pressure block on the membrane tray and a second end connected to the top rod. The portion between the first and second ends of the connecting plate is pivotally connected to the connector. A protrusion located above the membrane tray is provided on the line connecting the rotation center of the membrane tray and the filter membrane assembly. The elastic element is configured to drive the second end of the connecting plate toward the second roller. The distance between the rotation center of the membrane tray and the protrusion is equal to the distance between the rotation center of the membrane tray and the second roller. The pressure block on the membrane tray can move up and down relative to the top plate of the membrane tray.
[0016] Furthermore, the upper end of the connector is provided with a threaded hole located directly above the push rod, and a locking nut is provided in the threaded hole. The second end of the connecting plate is provided with a slot, and the upper end of the push rod passes through the slot. An adjusting nut is provided on the push rod that contacts the bottom of the second end of the connecting plate. The elastic element is located between the locking nut and the connecting plate.
[0017] On the other hand, a particulate matter sampling membrane replacement method is provided, which uses the above-mentioned automatic membrane replacement device for particulate matter sampling to perform automatic membrane replacement.
[0018] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects: a) The automatic membrane changer for particulate matter sampling provided by this invention achieves automatic membrane replacement through a pressing sample feeding mechanism and a filter membrane transmission mechanism, replacing manual membrane replacement, greatly extending the operation and maintenance cycle of the equipment. Each time, the maintenance personnel only need to remove the old membrane in the equipment and replace it with a new membrane to achieve continuous operation of the equipment and reduce maintenance costs.
[0019] b) The automatic membrane changer for particulate matter sampling provided by the present invention optimizes the running path of the membrane carrier by pressing the sample injection mechanism and the filter membrane transmission mechanism, shortens the running trajectory, and minimizes the overall volume of the membrane changer without affecting the operation. It is easy to transport and can be placed next to the equipment that needs it. It can be connected to the gas circuit of other equipment that needs it and the filter membrane suitable for other equipment can be replaced. It is compatible with various equipment that needs it. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of this specification 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 recorded in the embodiments of this specification. For those skilled in the art, other drawings can be obtained based on these drawings.
[0021] Figure 1 This is a schematic diagram of the first angle structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the second angle structure of Embodiment 1 of the present invention; Figure 3 This is a front view of Embodiment 1 of the present invention; Figure 4 This is a cross-sectional view of Embodiment 1 of the present invention; Figure 5 This is a partial structural diagram of Embodiment 1 of the present invention; Figure 6 This is a partial structural cross-sectional schematic diagram of Embodiment 1 of the present invention.
[0022] Figure 7 This is a perspective view of Embodiment 2 of the present invention.
[0023] Figure 8 This is a cross-sectional view of Embodiment 2 of the present invention.
[0024] Figure 9 for Figure 8 A magnified view of section I in the middle.
[0025] Figure 10 This is a structural diagram of the connector in Embodiment 2 of the present invention.
[0026] Figure 11 This is a structural diagram of the connecting plate and the pivot after assembly in Embodiment 2 of the present invention.
[0027] Figure label: 1. Membrane carrier upper pressure block; 2. Carrier membrane top plate; 3. Guide roller; 4. Membrane carrier; 5. Turntable bearing; 6. Photoelectric sensor; 7. Light shield; 8. Carrier membrane tray; 9. Gear motor one; 10. Gear motor two; 11. Carrier membrane bottom plate; 12. Push rod gear; 13. Push rod rack; 14. Membrane carrier lower pressure block; 15. Tray shaft; 16. Coupling; 17. Pressing part carrier block; 18. Linear bearing; 19. Sampling gas inlet; 20. 21. Sampling gas outlet; 22. Gas channel one; 23. Gas channel two; 24. Gas channel three; 25. First sealing ring; 26. Second sealing ring; 27. Third sealing ring; 28. Connecting seat; 29. Second roller; 30. Wheel frame; 31. Top rod; 31. Connecting piece; 3101. Threaded hole; 32. Connecting plate; 3201. Groove; 33. Elastic element; 34. Adjusting nut; 35. Protrusion; 36. Locking nut; 37. Pivot. Detailed Implementation
[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. It should be noted that, unless otherwise specified, the implementation methods and features in the implementation methods in this disclosure can be combined, separated, interchanged, and / or rearranged. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0029] In the accompanying drawings, the dimensions and relative dimensions of components may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a specific process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, the same reference numerals denote the same components.
[0030] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “the” are intended to include the plural forms as well. Furthermore, when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, integrals, steps, operations, parts, components, and / or groups thereof, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, parts, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, thus explaining the inherent biases in measurements, calculated values, and / or provided values that would be recognized by one of ordinary skill in the art.
[0031] Example 1 A specific embodiment of the present invention, such as Figures 1 to 6 As shown, an automatic membrane changer for particulate matter sampling is disclosed, comprising: The compression injection mechanism has an upper membrane pressure block 1, a lower membrane pressure block 14, and a lifting drive assembly. The upper membrane pressure block 1 is located directly above the lower membrane pressure block 14. The lifting drive assembly is configured to drive the lower membrane pressure block 14 to rise during sampling and seal and compress it with the upper membrane pressure block 1 to achieve the connection of the sampling gas path, and to drive the lower membrane pressure block 14 to fall after sampling is completed and separate it from the upper membrane pressure block 1 to achieve the disconnection of the sampling gas path. The filter membrane transmission mechanism has a membrane carrier tray 8 and a rotation drive assembly. Multiple filter membrane assemblies are detachably mounted on the membrane carrier tray 8. The rotation drive assembly is configured to drive the membrane carrier tray 8 to rotate, causing the multiple filter membrane assemblies to rotate sequentially to the sampling position. The filter membrane assembly at the sampling position is located between the upper pressure block 1 and the lower pressure block 14 of the membrane carrier. During the sampling process, the multiple filter membrane assemblies are rotated sequentially between the upper pressure block 1 and the lower pressure block 14 of the membrane carrier for sampling. The lifting drive assembly is provided with air passage 1 21, the membrane drag lower pressure block 14 is provided with air passage 22, and the membrane drag upper pressure block 1 is provided with air passage 3 23. Air passage 1 21, air passage 22 and air passage 3 23 are arranged coaxially and vertically. When the membrane drag lower pressure block 14 rises and presses against the membrane drag upper pressure block 1, the filter membrane assembly at the sampling position is sealed between air passage 22 and air passage 3 23 during each sampling. It can also connect with air passage 1 21, air passage 22 and air passage 3 23 under the drive of the lifting drive assembly to form a sealed sampling gas path. Then, air is introduced from the sampling gas inlet 19 of the membrane drag upper pressure block 1 to filter the gas to be tested.
[0032] This application integrates the gas passage into the lifting drive assembly, which simplifies the sampling gas path structure and eliminates the need for additional gas pipelines for connection. This simplifies the structure of the sampling gas path, making the device more compact and achieving miniaturization.
[0033] In this embodiment, the sampling gas path has a sampling gas inlet 19 and a sampling gas outlet 20. The sampling gas inlet 19 is located on the membrane drag pressure block 1. The top port of the third gas channel 23 is the sampling gas inlet 19, and the bottom port of the first gas channel 21 is the sampling gas outlet 20. The sampling gas outlet 20 is connected to the detection equipment through a pipeline.
[0034] In one optional embodiment, the drive assembly includes a second geared motor 10, a push rod gear 12, and a push rod rack 13. The push rod rack 13 is vertically adjustable and has a hollow structure. The hollow channel of the push rod rack 13 is an air passage 21, and the sampling gas outlet 20 is located on the push rod rack 13, serving as the port of the push rod rack 13. The top end of the push rod rack 13 is sealed to the membrane drag lower pressure block 14. The output shaft of the second geared motor 10 is equipped with a push rod gear 12, which meshes with the teeth on the outer wall of the push rod rack 13. The second geared motor 10 drives the push rod gear 12 to rotate, thereby raising and lowering the push rod rack 13. For example, when the second geared motor 10 drives the push rod rack 13 to move upward through the push rod gear 12, it will drive the membrane drag lower pressure block 14 to push the membrane drag 4 upward against the membrane drag upper pressure block 1, ensuring that both ends of the membrane drag are pressed tightly, thus achieving a seal of the entire air passage.
[0035] Furthermore, the drive assembly also includes a clamping block 17 and linear bearings 18. The push rod rack 13 is mounted on the clamping block 17 via the linear bearings 18; the geared motor 10 is fixedly mounted on the clamping block 17. For example, there are two linear bearings 18, positioned at the upper and lower parts of the push rod rack 13 and on the upper and lower sides of the push rod gear 12, allowing for more flexible up-and-down movement of the rack. The distance between the two linear bearings 18 is sufficient to meet the lifting and lowering distance required for the push rod rack 13, and they will not interfere with the push rod gear 12 during operation.
[0036] In this embodiment, the filter membrane transmission mechanism also has a membrane top plate 2 and a membrane bottom plate 11. The membrane top plate 2 is fixedly connected to the membrane bottom plate 11 by screws, and the membrane bottom plate 11 is fixedly mounted on the pressing block 17 by a connecting seat. The membrane drag pressing block 1 is fixed on the membrane top plate 2, and the membrane tray 8 is rotatably disposed in the space between the membrane top plate 2 and the membrane bottom plate 11.
[0037] In this embodiment, the rotation drive assembly includes a geared motor 9, which is mounted on the film base plate 11. The geared motor 9 drives the film tray 8 to rotate through a coupling 16 and a tray shaft 15. Specifically, the geared motor 9 is connected to the tray shaft 15 through the coupling 16, and the upper part of the tray shaft 15 is fixedly connected to the center of the film tray 8.
[0038] In one optional embodiment, guide rollers 3 are provided between the film tray 8 and the film base plate 11, and between the film tray 8 and the film top plate 2. The guide rollers 3 are configured to limit the vertical movement of the film tray 8. For example, three guide rollers 3 are installed on each of the film base plate 11 and the film top plate 2 to limit the vertical movement of the film tray 8 and ensure the rotational stability of the film tray 8. Further, annular grooves are provided on both the upper and lower surfaces of the film tray 8. The positions of the grooves correspond to the guide rollers 3. The guide rollers 3 on the film base plate 11 and the film top plate 2 are embedded in the grooves and can roll within the grooves, thereby limiting the vertical movement of the film tray 8.
[0039] In this embodiment, the particulate matter sampling automatic membrane changer also includes a control system, which is configured to control the start and stop of the first gear motor 9 and the second gear motor 10 according to a set program, so as to realize the automatic control of the particulate matter sampling automatic membrane change process.
[0040] In one optional embodiment, a photoelectric sensor 6 is provided on the top plate 2 of the carrier membrane, and multiple light-shielding plates 7 are provided on the carrier membrane tray 8 corresponding to the positions of the filter membrane components. The light-shielding plates 7 can rotate with the carrier membrane tray 8. When the light-shielding plate 7 rotates to the position where it blocks the photoelectric sensor 6, the filter membrane component at the corresponding position rotates into place, and the carrier membrane tray 8 stops rotating. The control system is connected to the photoelectric sensor 6 for signal control, and can receive the filter membrane component rotation into place signal emitted by the photoelectric sensor 6. Based on the received filter membrane component rotation into place signal, the control system can control the geared motor 9 to operate. That is, the light-shielding plate 7 can rotate with the carrier membrane tray 8, and when it rotates into place, it can block the photoelectric sensor 6 and trigger the photoelectric sensor 6 to send a filter membrane component rotation into place signal to the control system. The control system then controls the geared motor 9 to stop the carrier membrane tray 8 from rotating.
[0041] In this embodiment, the filter membrane assembly includes a membrane carrier 4 and a filter membrane disposed on the membrane carrier 4. The membrane carrier 4 is used to install and support the filter membrane. The membrane carrier tray 8 is provided with multiple holes for placing the membrane carrier 4. For example, the membrane carrier tray 8 has 6 holes. Among the multiple holes of the membrane carrier tray 8, the hole between the upper pressure block 1 and the lower pressure block 14 of the membrane carrier is the sampling hole. Only one filter membrane assembly is sampled at a time. The filter membrane assembly that has completed sampling is moved away from the sampling hole position, and at the same time, the next unsampled filter membrane assembly is rotated to the sampling hole position for sampling, thereby realizing the switching and sampling of multiple filter membrane assemblies in sequence.
[0042] To improve the sealing of the connected sampling gas path, sealing rings are provided between the membrane carrier 4 and the upper pressure block 1, between the membrane carrier 4 and the lower pressure block 14, and between the push rod rack 13 and the lower pressure block 14. Specifically, a first sealing ring 24 is provided between the bottom end face of the upper pressure block 1 and the upper surface of the membrane carrier 4, a second sealing ring 25 is provided between the top end face of the lower pressure block 14 and the lower surface of the membrane carrier 4, and a third sealing ring 27 is used to seal the connection between the top end of the push rod rack 13 and the lower pressure block 14.
[0043] Furthermore, the first sealing ring 24, the second sealing ring 25, and the third sealing ring 27 are all O-rings; the bottom end face of the membrane tray upper pressure block 1 is provided with a first annular groove, the first sealing ring 24 is installed in the first annular groove and protrudes from the bottom end face of the membrane tray upper pressure block 1; the top end face of the membrane tray lower pressure block 14 is provided with a second annular groove, the second sealing ring 25 is installed in the second annular groove and protrudes from the top end face of the membrane tray lower pressure block 14.
[0044] Example 2 See Figures 7 to 11 As shown, this embodiment adds an automatic lifting mechanism for the film tray pressure block 1 based on embodiment 1. During the rotation of the film tray 8, the automatic lifting mechanism for the film tray pressure block 1 can automatically drive the film tray pressure block 1 to rise or fall.
[0045] The automatic lifting mechanism for the membrane tray pressing block 1 includes a second roller 28, a wheel frame 29, a top rod 30, a connecting member 31, a connecting plate 32, and an elastic member 33. The second roller 28 is connected to the wheel frame 29 and can rotate relative to the wheel frame 29. Both the second roller 28 and the wheel frame 29 are located between the membrane tray 8 and the membrane top plate 2. The top rod 30 is perpendicular to the membrane top plate 2 and passes through the upper and lower end surfaces of the membrane top plate 2. The top rod 30 can move up and down relative to the membrane top plate 2. The lower end of the top rod 30 is fixedly connected to the wheel frame 29. The top rod 30 is located on the line connecting the rotation center of the membrane tray 8 and the membrane tray pressing block 1. The connecting member 31 is fixed to the membrane top plate. Above plate 2, connecting plate 32 has a first end connected to membrane tray pressure block 1 and a second end connected to top rod 30. The portion between the first end and the second end of connecting plate 32 is pivotally connected to connector 31 via pivot 37. A protrusion 35 is provided on the line connecting the rotation center of membrane tray 8 and filter membrane assembly, located above membrane tray 8. Elastic member 33 is configured to drive the second end of connecting plate 32 toward second roller 28. The distance between the rotation center of membrane tray 8 and protrusion 35 is equal to the distance between the rotation center of membrane tray 8 and second roller 28. Membrane tray pressure block 1 can move up and down relative to membrane top plate 2.
[0046] like Figure 7As shown, the two ends of the protrusion 35 smoothly transition to the upper surface of the membrane tray 8, the middle of the protrusion 35 protrudes upward, and the bottom of the second roller 28 contacts the top surface of the membrane tray 8 or the protrusion 35. When the membrane tray 8 rotates, as one of the filter membrane components approaches the sampling position, the bottom of the second roller 28 first contacts the edge of the protrusion 35. As the membrane tray 8 rotates, the protrusion 35 gradually lifts the second roller 28, and the connecting plate 32 drives the membrane dragging pressure block 1 to gradually contact the filter membrane component. When one of the filter membrane components rotates to the sampling position, the bottom of the second roller 28 contacts the top of the protrusion 35, and the protrusion 35 lifts the second roller 28 to its highest position. The top of the push rod 30... The first end of the connecting plate 32 lifts the second end of the connecting plate 32, and the first end of the connecting plate 32 drives the membrane dragging block 1 to descend. At this time, the membrane dragging block 1 is in close contact with the filter membrane assembly to prevent gas leakage. During the process of the filter membrane assembly leaving the sampling position, under the combined action of the elastic force of the elastic element 33 and the gravity of the top rod 30, the wheel frame 29 and the second roller 28, the second roller 28 descends along the slope of the edge of the protrusion 35, and the first end of the connecting plate 32 drives the membrane dragging block 1 to rise and separate from the filter membrane assembly.
[0047] Through the aforementioned automatic lifting mechanism of the membrane carrier pressure block 1, a tight contact and seal between the membrane carrier pressure block 1 and the filter membrane assembly is achieved only when the filter membrane assembly is in the sampling position. As the filter membrane assembly approaches the sampling position, the pressure between the membrane carrier pressure block 1 and the filter membrane assembly gradually increases; as the filter membrane assembly moves away from the sampling position, the pressure between the membrane carrier pressure block 1 and the filter membrane assembly gradually decreases. During the rotation of the membrane carrier tray 8, the automatic lifting mechanism of the membrane carrier pressure block 1 ensures low friction between the membrane carrier pressure block 1 and the filter membrane assembly, which not only reduces the running resistance of the membrane carrier tray 8 but also helps extend the service life of the first sealing ring 24.
[0048] To facilitate the installation of the elastic element 33, the upper end of the connector 31 is provided with a threaded hole 3101 located directly above the push rod 30. A locking nut 36 is installed in the threaded hole 3101. The second end of the connecting plate 32 is provided with a slot 3201. The upper end of the push rod 30 passes through the slot 3201. An adjusting nut 34 is provided on the push rod 30, which contacts the bottom of the second end of the connecting plate 32. The elastic element 33 is located between the locking nut 36 and the connecting plate 32. In a specific implementation, the aforementioned elastic element 33 can be a compression spring. To prevent the elastic element 33 from popping out, the lower end of the locking nut 36 is provided with a limiting post. The upper end of the elastic element 33 is sleeved on the outside of the limiting post, and the lower end of the elastic element 33 is sleeved on the outside of the push rod 30.
[0049] The present invention also provides a particulate matter sampling membrane replacement method, wherein the aforementioned automatic particulate matter sampling membrane changer is used to replace the membrane during the sampling process.
[0050] The particulate matter sampling membrane replacement method specifically includes the following steps: Install the filter membrane on the membrane tray 4, place the membrane tray 4 with the filter membrane installed into the hole of the membrane carrier tray 8, start the geared motor 9, the geared motor 9 drives the membrane carrier tray 8 to rotate, when the light shield 7 rotates to the blocking position of the photoelectric sensor 6, the light shield 7 triggers the photoelectric sensor 6, the geared motor 9 is turned off, the membrane carrier tray 8 stops rotating, and another membrane tray 4 with a filter membrane installed is placed in the hole upstream of the photoelectric sensor 6. Repeat the above steps until all holes are filled with membrane trays.
[0051] After all membrane carriers 4 are installed, start the geared motor 10. The push rod gear 12 drives the push rod rack 13 to rise, causing the membrane carrier lower pressure block 14 to rise until it presses against the membrane carrier 4 from bottom to top. The membrane carrier 4 is clamped between the membrane carrier upper pressure block 1 and the membrane carrier lower pressure block 14, at which point the sampling gas path is connected. Gas sampling begins. Gas enters through the sampling gas inlet 19 of the sampling gas path. The gas passes through the filter membrane on the membrane carrier 4, filtering out large particulate impurities. The remaining gas flows out through the filter membrane from the sampling gas outlet 20 and enters the detection equipment to obtain the detection results. The sampling cycle can be set as needed, for example, once a week. When it is necessary to switch filter membranes, start the second geared motor 10. The second geared motor 10 drives the push rod rack 13 to descend through the push rod gear 12, thereby causing the membrane support block 14 to move downward and release the membrane support 4. The sampling gas path changes from connected to disconnected. At this time, start the first geared motor 9. The first geared motor 9 drives the membrane tray 8 to rotate until the light shield 7 of the next aperture rotates to the blocking position of the photoelectric sensor 6, triggering the photoelectric sensor 6. The first geared motor 9 stops operating, and the membrane tray 8 stops rotating. At this time, the next sampling aperture has been switched. Start the second geared motor 10 again, so that the membrane support block 14 presses the membrane support 4 and the membrane support block 14 from bottom to top, and the sampling gas path is connected again, and air intake sampling begins. Repeat the above steps until all filter membranes on all apertures are used up. Then all membrane supports 4 can be removed and replaced with new filter membranes, realizing automatic membrane replacement.
[0052] Compared with the prior art, the automatic membrane changer and membrane changing method for particulate matter sampling provided in this embodiment have the following beneficial effects: 1. Automatic membrane replacement is achieved through the compression injection mechanism and the filter membrane transmission mechanism, which replaces manual membrane replacement and greatly extends the operation and maintenance cycle of the equipment. Each time, the maintenance personnel only need to remove the old membrane from the equipment and replace it with a new membrane to achieve continuous operation of the equipment and reduce maintenance costs.
[0053] 2. Compared to existing particulate matter sampling membrane changers with their bulky chassis, the membrane changer in this application has a simpler and more compact structure. The optimized membrane carriage path, achieved through a compression injection mechanism and a filter membrane drive mechanism, shortens the travel distance and minimizes the overall size of the membrane changer without affecting operation. Due to its small size, the device is easy to transport and can be placed anywhere next to the equipment requiring it. It can be easily connected to the gas path of other equipment and have its filter membrane replaced with one suitable for those devices, making it compatible with various types of equipment.
[0054] 3. The automatic membrane changer for particulate matter sampling has a simpler structure, fewer moving parts for automatic membrane changing, and can be precisely controlled to start and stop the membrane changer through photoelectric sensors, reducing the probability of membrane changer problems. At the same time, some mechanical problems can be solved remotely through software control.
[0055] 4. The carrier film tray is restricted from moving up and down by guide rollers, making the carrier film tray rotate more smoothly and reducing mechanical failures.
[0056] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above description is only a specific embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. An automatic membrane changer for particulate matter sampling, characterized in that, include: The filter membrane transmission mechanism includes a membrane carrier tray, a rotation drive assembly, a membrane carrier top plate, and a membrane carrier bottom plate. Multiple filter membrane assemblies are detachably installed on the membrane carrier tray. The rotation drive assembly is configured to drive the membrane tray to rotate, causing the plurality of filter membrane assemblies to rotate sequentially to the sampling position; the top plate and the bottom plate of the membrane are fixedly connected, and the membrane tray is rotatably disposed in the space between the top plate and the bottom plate of the membrane; The sample injection mechanism includes an upper membrane pressure block, a lower membrane pressure block, and a lifting drive assembly. The upper membrane pressure block is located directly above the lower membrane pressure block and connected to the top plate of the membrane carrier. The filter membrane assembly at the sampling position is located between the upper and lower membrane pressure blocks. The lifting drive assembly is configured to drive the lower membrane pressure block to rise and fall. The lifting drive assembly has a built-in air passage one, the membrane drag lower pressure block has an air passage two, and the membrane drag upper pressure block has an air passage three; the air passage one, the air passage two, and the air passage three can be connected to form a sealed sampling air passage when the lifting drive assembly drives the membrane drag lower pressure block to rise.
2. The automatic membrane changer for particulate matter sampling according to claim 1, characterized in that, The first airway, the second airway, and the third airway are arranged vertically on the same axis.
3. The automatic membrane changer for particulate matter sampling according to claim 2, characterized in that, The sampling gas path has a sampling gas inlet and a sampling gas outlet. The top port of the third gas path is the sampling gas inlet, and the bottom port of the first gas path is the sampling gas outlet.
4. The automatic membrane changer for particulate matter sampling according to claim 2, characterized in that, The drive assembly includes a second geared motor, a push rod gear, and a push rod rack. The push rod rack is vertically adjustable and has a hollow structure. The hollow channel of the push rod rack serves as the first air passage. The top end of the push rod rack is sealed to the membrane drag lower pressure block. The output shaft of the second geared motor is equipped with a push rod gear, which meshes with the teeth on the outer wall of the push rod rack. The second geared motor drives the push rod gear to rotate, thereby raising and lowering the push rod rack.
5. The automatic membrane changer for particulate matter sampling according to claim 4, characterized in that, The drive assembly also includes a pressing block and a linear bearing. The push rod rack is mounted on the pressing block via the linear bearing. The second geared motor is fixedly mounted on the pressing block, and the film base plate is fixedly mounted on the pressing block via a connecting seat.
6. The automatic membrane changer for particulate matter sampling according to claim 5, characterized in that, The filter assembly includes a membrane carrier and a filter membrane disposed on the membrane carrier, and the membrane carrier tray is provided with a plurality of holes for placing the membrane carrier.
7. The automatic membrane changer for particulate matter sampling according to claim 1, characterized in that, A photoelectric sensor is provided on the top plate of the carrier membrane, and multiple light-shielding plates are provided on the carrier membrane tray corresponding to the position of the filter membrane assembly. The light-shielding plates can rotate with the carrier membrane tray. When the light-shielding plate rotates to the position where the photoelectric sensor is blocked, the filter membrane assembly at the corresponding position rotates into place, and the carrier membrane tray stops rotating.
8. The automatic membrane changer for particulate matter sampling according to any one of claims 1 to 7, characterized in that, It also includes a second roller, a wheel frame, a top rod, a connector, a connecting plate, and an elastic element. The second roller is connected to the wheel frame and can rotate relative to the wheel frame. Both the second roller and the wheel frame are located between the film carrier tray and the film carrier top plate. The top rod is perpendicular to the film carrier top plate and passes through the upper and lower end faces of the film carrier top plate. The top rod can move up and down relative to the film carrier top plate. The lower end of the top rod is connected to the wheel frame. The top rod is located on the line connecting the rotation center of the film carrier tray and the pressure block on the film carrier. The connector is fixed above the film carrier top plate. The connecting plate has a first end connected to the pressure block on the membrane carrier and a second end connected to the top rod. The portion between the first and second ends of the connecting plate is pivotally connected to the connector. A protrusion located above the membrane carrier is provided on the line connecting the rotation center of the membrane carrier tray and the filter membrane assembly. The elastic element is configured to drive the second end of the connecting plate to move toward the second roller. The distance between the rotation center of the membrane carrier tray and the protrusion is equal to the distance between the rotation center of the membrane carrier tray and the second roller. The pressure block on the membrane carrier can move up and down relative to the top plate of the membrane carrier.
9. The automatic membrane changer for particulate matter sampling according to claim 8, characterized in that, The upper end of the connector is provided with a threaded hole located directly above the top rod, and a locking nut is provided in the threaded hole. The second end of the connecting plate is provided with a slot, and the upper end of the top rod passes through the slot. An adjusting nut is provided on the top rod that contacts the bottom of the second end of the connecting plate. The elastic element is located between the locking nut and the connecting plate.
10. A method for sampling and membrane replacement of particulate matter, characterized in that, Automatic membrane replacement is performed using the particulate matter sampling automatic membrane changer according to any one of claims 1 to 9.