Single-particle light scattering particulate matter automatic analysis gas path system

Abstract

The application relates to a single-particle light-scattering particle matter automatic analysis gas path system, relates to the field of gas analysis and treatment, and comprises a case, wherein a scattered light detection structure is arranged in the case; the scattered light detection structure comprises a main body shell fixed in the case, a communication block is arranged in the main body shell, and an irradiation cavity is arranged in the communication block; an air inlet pipeline and an air outlet pipeline which are in communication with the irradiation cavity are arranged outside the main body shell; a slow-flow pipeline which is in communication with the air outlet pipeline is further arranged in the case; a flowmeter, a laminar flow buffer joint, a proportional valve and an air suction pump are sequentially arranged on the slow-flow pipeline; a light inlet conical hole is arranged in the communication block, a first condenser lens is fixed at one end of a light inlet channel close to the light inlet conical hole; a reflection conical hole is arranged in the communication block, and a second condenser lens is fixed at one end of a reflection channel close to the reflection conical hole; a cleaning mechanism for cleaning the mirror surfaces of the first condenser lens and the second condenser lens is arranged in the air outlet pipeline. The application has the effect of improving detection accuracy.

Description

Technical Field

[0001] This application relates to the field of gas analysis and processing, and in particular to an automatic gas path system for analyzing single-particle light-scattering particulate matter. Background Technology

[0002] Currently, particulate matter monitoring technologies mainly include gravimetric methods, beta-ray absorption methods, and light scattering methods. With technological advancements, these technologies play a crucial role in many fields such as environmental monitoring and industrial production. Among them, light scattering methods, with their advantages of fast response speed and ability to analyze single particles, have gradually become a research hotspot. In recent years, with the increasing demand for PM2.5 and PM10 monitoring, higher requirements have been placed on the accuracy and reliability of particulate matter analyzers.

[0003] Currently, particulate matter monitoring technology is constantly developing and its application scenarios are becoming increasingly widespread. Existing light scattering particulate matter analysis gas path systems mainly include an entrance light channel, a reflection channel, a detection channel, and an optical detection structure that sequentially transmit detection light. The entrance light channel is equipped with an illumination device, and an irradiation cavity is located between the entrance light channel and the reflection channel. A condenser lens is located in the irradiation cavity. The illumination device illuminates the gas flow to be detected in the irradiation cavity through the condenser lens, causing the particles in the gas flow to emit scattered light. However, the gas flow to be detected contains impurities, which are easily adhered to and deposited on the surface of the condenser lens. After a certain period of use, due to the lack of an effective cleaning mechanism, the condenser lens becomes covered with a large amount of impurities, which affects the accuracy of the detection and cannot guarantee the accuracy of the system's optical structure measurement. Summary of the Invention

[0004] To improve the accuracy of detection, this application provides an automatic gas path system for analyzing single-particle light scattering particulate matter.

[0005] This application provides an automated gas path system for single-particle light scattering particulate matter analysis, which adopts the following technical solution: An automated gas path system for single-particle light-scattering particulate matter analysis includes: A chassis, wherein a light scattering detection structure is provided inside the chassis; The astigmatism detection structure includes a main body shell fixed inside the chassis. The main body shell has an incident light channel and a detection channel inside. A reflection channel is also provided between the incident light channel and the detection channel. A reflection component is provided between the detection channel and the reflection channel. The main body shell has a connecting block inside, and an irradiation chamber is opened inside the connecting block; the main body shell has an air inlet pipe and an air outlet pipe communicating with the irradiation chamber on the outside; the chassis also has a slow flow pipe communicating with the air outlet pipe, and a filter assembly for filtering impurities in the airflow to be detected is provided between the air outlet pipe and the slow flow pipe; a flow meter, a laminar flow buffer joint, a proportional valve and a vacuum pump are also provided in sequence on the slow flow pipe. The connecting block has an entrance light cone-shaped hole inside, the irradiation cavity is connected to the entrance light channel through the entrance light cone-shaped hole, and a first focusing lens is fixed at one end of the entrance light channel near the entrance light cone-shaped hole. The connecting block has a reflective conical hole inside, the irradiation cavity is connected to the reflective channel through the reflective conical hole, and a second focusing lens is fixed at one end of the reflective channel near the reflective conical hole; The air outlet pipe is equipped with a cleaning mechanism for cleaning the surfaces of the first and second condenser lenses.

[0006] By adopting the above technical solution, the automatic gas path system for single-particle light scattering particulate matter analysis can achieve accurate analysis of particulate matter. The gas to be detected first enters the irradiation chamber through the inlet pipe, then enters the outlet pipe through the irradiation chamber, and then passes through the filter component between the outlet pipe and the slow flow pipe to filter out impurities in the gas flow. After that, it flows through the flow meter, laminar flow buffer joint and proportional valve on the slow flow pipe in sequence, and is finally discharged by the vacuum pump. The scattered light detection structure inside the chassis features an input light channel, a detection channel, and a reflection channel that work together with a reflection component to accurately receive and detect the scattered light emitted by particles in the airflow being tested. The irradiation cavity within the connecting block is connected to the input light channel and the reflection channel via an input cone-shaped aperture and a reflection cone-shaped aperture, respectively. The first and second focusing lenses in the input and reflection channels ensure focused light transmission, improving the sensitivity of the scattered light detection. A filter component between the outlet pipe and the slow-flow pipe filters impurities in the airflow being tested, preventing them from entering subsequent components and affecting detection accuracy and equipment lifespan. A flow meter on the slow-flow pipe monitors the airflow in real time, facilitating precise airflow control. A laminar flow buffer connector converts turbulent gas flow into laminar flow, making the airflow more stable and reducing the impact of airflow disturbances on the detection results. A proportional valve precisely adjusts the airflow, and a pump provides power for the airflow. The cleaning mechanism inside the air outlet duct can clean the surfaces of the first and second condensing lenses, preventing impurities in the airflow to be tested from adhering to and depositing on the lens surfaces, which would affect the accuracy of the test. Regular cleaning improves the accuracy of the test results. Through the coordinated work of various components, this air path system improves sampling efficiency, optimizes airflow stability, simplifies the air path structure, and reduces maintenance difficulty.

[0007] Optionally, the cleaning mechanism includes: The guide rail is fixed inside the air outlet pipe and is aligned with the extension direction of the air outlet pipe. The movable seat is slidably connected to the guide rail; Two vertically arranged rotating shafts are rotatably connected within the movable base, wherein the axis of one rotating shaft is perpendicular to the surface of the first condenser lens, and the axis of the other rotating shaft is perpendicular to the surface of the second condenser lens; An electric telescopic rod is fixed to the end of the rotating shaft; A rotating base is fixed to the output end of the electric telescopic rod. The rotating shaft is provided with multiple extended cleaning arms along its circumference. A supporting cleaning arm is provided between the extended cleaning arms and the rotating base. The supporting cleaning arm is fixed to the rotating base and is slidably connected to the extended cleaning arm. Flexible brushes are provided on the side of the rotating base, the supporting cleaning arm, and the extended cleaning arm away from the electric telescopic rod. An extension reset assembly is disposed between the extension cleaning arm and the rotating seat, and is used to drive the extension cleaning arm to move toward or away from the rotating seat. A movable component, located at the end of the air outlet pipe, is used to drive the movable seat to move along the extension path of the air outlet pipe; A linkage component is located between the two rotating shafts to drive the two rotating shafts to rotate synchronously.

[0008] By adopting the above technical solution, the guide rail is fixed inside the air outlet pipe and is consistent with the extension direction of the air outlet pipe, providing guidance for the movement of the movable seat, so that the movable seat can slide stably along the extension path of the air outlet pipe. The movable seat is slidably connected to the guide rail, and can move flexibly on the guide rail under the drive of the moving component. The two vertically set rotating shafts can rotate synchronously under the action of the linkage component, ensuring that the cleaning operation of the first condensing lens and the second condensing lens is carried out synchronously. The electric telescopic rod is fixed to the end of the rotating shaft, and can adjust the position of the rotating seat as needed, so that the flexible brush can better fit the lens surface. The rotating seat is fixed to the output end of the electric telescopic rod. Multiple extended cleaning arms arranged circumferentially on the rotating shaft are connected to the rotating seat through the support cleaning arm, and the support cleaning arm and the extended cleaning arm are slidably connected. The extension reset component can drive the extended cleaning arm to move closer to or further away from the rotating seat. When the rotating base rotates, under the action of centrifugal force, the extended cleaning arm moves away from the rotating base, allowing the flexible brush to cover the entire lens surface. After cleaning, once the rotating shaft stops rotating, the extended reset assembly pulls the extended cleaning arm closer to the rotating base to reset it, thus retracting the extended cleaning arm. This also facilitates the retraction of the extended cleaning arm, support cleaning arm, and rotating base into the movable base after passing through the entrance cone or reflection cone. The movable assembly is located at the end of the air outlet pipe. By moving the movable base, it moves the extended cleaning arm, support cleaning arm, and rotating base to the outside of the air outlet pipe to clean or replace the flexible brush. The linkage assembly can simultaneously achieve synchronous rotation of the two rotating shafts, reducing the need for a power source and saving space. The cleaning mechanism can quickly clean impurities deposited on the surfaces of the first and second condenser lenses, preventing impurities from affecting the accuracy of the detection and improving the accuracy of the detection results. It can also dynamically clean or replace the flexible brush, ensuring the long-term stable impurity removal effect of the cleaning mechanism and maintaining the long-term stable optical structure measurement accuracy, stability, and sustainability of the system.

[0009] Optionally, the linkage component includes: The drive motor is fixed inside the movable base; A drive bevel gear is fixedly sleeved on the output shaft of the drive motor. Two linkage shafts are also rotatably connected inside the movable seat. A first transmission bevel gear and a second transmission bevel gear are fixedly sleeved at both ends of the linkage shafts respectively. The first transmission bevel gear meshes with the drive bevel gear. The driven bevel gear is fixedly sleeved on the outside of the rotating shaft, and the second transmission bevel gear meshes with the driven bevel gear.

[0010] By adopting the above technical solution, when the drive motor starts, it drives the bevel gear to rotate, which in turn drives the linkage shaft to rotate through meshing with the first transmission bevel gear. This causes the second transmission bevel gear to rotate, and the second transmission bevel gear then drives the driven bevel gear to rotate, thereby achieving synchronous rotation of the two rotating shafts. The linkage component avoids the need to set a separate power source for each rotating shaft, reduces the number of power sources, saves the space required to install the power sources, and makes the structure of the entire cleaning mechanism more compact.

[0011] Optionally, the extended reset component includes: A counterweight is fixed to the end of the extended cleaning arm away from the rotating base; A return spring is fixed between the extended cleaning arm and the rotating base, and is used to drive the extended cleaning arm to move closer to the rotating base.

[0012] By adopting the above technical solution, when the rotating seat rotates to clean the surfaces of the first and second condenser lenses, the counterweight, fixed at the end of the extended cleaning arm furthest from the rotating seat, can, under the action of centrifugal force, drive the extended cleaning arm to overcome the tension of the return spring and move away from the rotating seat. This allows the extended cleaning arm to unfold, enabling the flexible brush to cover the entire surface of the first or second condenser lens, improving the thoroughness of the cleaning. After cleaning is complete and the rotating shaft stops rotating, the return spring pulls the extended cleaning arm closer to the rotating seat to reset, causing the extended cleaning arm to retract. This facilitates the extended cleaning arm passing through the entrance cone or reflection cone and being stored in the moving seat, reducing the impact on normal system operation when not cleaning.

[0013] Optionally, the counterweight is tapered on the side furthest from the extended cleaning arm.

[0014] By adopting the above technical solution, the side of the counterweight away from the extended cleaning arm is set as a conical surface, so that the side of the counterweight is adapted to the taper of the light-incident conical hole or the reflective conical hole. When the cleaning mechanism is working, the rotating shaft rotates and drives the rotating seat to rotate. Under the action of centrifugal force, the counterweight on the extended cleaning arm drives the extended cleaning arm to move away from the rotating seat. At this time, since the conical surface of the counterweight is adapted to the taper of the light-incident conical hole or the reflective conical hole, the flexible brush can better fit the mirror surface of the first condensing lens or the second condensing lens for cleaning, reducing cleaning dead angles.

[0015] Optionally, the rotating seat, the supporting cleaning arm, and the extended cleaning arm are respectively fixed with a first connecting seat, a second connecting seat, and a third connecting seat on the side away from the electric telescopic rod. A first rubber sleeve, a second rubber sleeve, and a third rubber sleeve are respectively sleeved on the outside of the first connecting seat, the second connecting seat, and the third connecting seat. A flexible brush is fixed on the outside of each of the first rubber sleeve, the second rubber sleeve, and the third rubber sleeve.

[0016] By adopting the above technical solution, the rotating seat, the supporting cleaning arm, and the extended cleaning arm are fitted with a first rubber sleeve, a second rubber sleeve, and a third rubber sleeve on the side away from the electric telescopic rod. The rubber sleeves have a certain degree of flexibility and elasticity. When the brush needs to be removed for cleaning or replaced due to wear and aging after a certain period of use, it can be quickly removed through the rubber sleeves, improving the convenience of removing or replacing the flexible brush.

[0017] Optionally, the movable seat is equipped with a negative pressure fan, and a dust collection channel is provided on one side of the movable seat extending from the negative pressure fan to the movable seat. A dust filter box with a filter screen is provided on the side of the negative pressure fan away from the dust collection channel. The movable seat is equipped with a storage slot adapted to the dust filter box, and the dust filter box is located in the storage slot.

[0018] By adopting the above technical solution, when cleaning the surfaces of the first and second condensing lenses, a flexible brush scrapes off the impurities on the lens surfaces. At this time, the negative pressure fan inside the moving base starts, and the negative pressure generated will draw the scraped impurities into the dust collection box with a filter screen through the dust collection channel. Air is discharged from the filter screen holes on the dust collection box, while the impurities are collected in the dust collection box, thereby preventing impurities from re-adhering to the lens surfaces and ensuring the cleaning effect. At the same time, the dust collection box is placed in a storage slot that is compatible with the moving base, which is convenient for installation and disassembly, and convenient for cleaning or replacing the dust collection box.

[0019] Optionally, the filter assembly includes a filter chamber fixed to the outside of the chassis and an end cap threaded to the outside of the filter chamber. The filter chamber is connected to both the air outlet pipe and the slow-flow pipe. A filter bracket fixed to the inner wall of the filter chamber and a filter membrane placed on the filter bracket are also provided between the air outlet pipe and the slow-flow pipe.

[0020] By adopting the above technical solution, after the airflow to be tested flows into the filter chamber through the outlet pipe, the filter membrane can filter out the impurities in it. After filtration, it enters the slow flow pipe, preventing impurities from entering the slow flow pipe and subsequent components. The end cap is threaded to the outside of the filter chamber, which is convenient for disassembly and installation. When it is necessary to replace the filter membrane, the end cap can be opened for operation, which improves the maintainability of the equipment and extends the service life of the entire air circuit system.

[0021] Optionally, the moving component includes: A support frame is located at the end of the air outlet pipe and fixed to the inner wall of the filter chamber; A winding drum is rotatably connected to the support frame. A first traction rope and a second traction rope are wound on the winding drum. The first traction rope and the second traction rope are wound in opposite directions. Both the first traction rope and the second traction rope are connected to the movable seat.

[0022] By adopting the above technical solution, when the winding drum rotates in the forward direction, since the first traction rope and the second traction rope are wound in opposite directions, the first traction rope will drive the moving seat to move along the guide rail towards the side closer to the irradiation cavity; when the winding drum rotates in the reverse direction, the second traction rope will drive the moving seat to move along the guide rail towards the side farther from the irradiation cavity, so that the moving seat can move flexibly on the extension path of the air outlet pipe, which makes it convenient for the cleaning mechanism to reach the surface of the first condensing lens and the second condensing lens for cleaning operations, or to move the moving seat to the outside of the air outlet pipe to clean the flexible brush, ensuring the cleanliness of the surface of the first condensing lens and the second condensing lens.

[0023] Optionally, a backflush pipe is also provided between the air intake pipe and the chassis. The backflush pipe is equipped with a backflush valve. One end of the backflush pipe is connected to a blowing device, and the other end is connected to the air intake pipe.

[0024] By adopting the above technical solution, the intake pipe can be cleaned regularly. When the set time is reached, the backflush valve opens, and the blowing device blows air into the intake pipe through the backflush pipe to clean the impurities on the inner wall of the intake pipe, thus preventing the accumulation of impurities in the intake pipe from affecting the normal transmission of airflow and particulate matter.

[0025] In summary, this application includes at least one of the following beneficial technical effects: This automatic gas path system for single-particle light scattering particulate matter analysis can achieve accurate analysis of particulate matter. Through the coordinated work of components such as the filter assembly, the various parts on the slow-flow pipe, and the cleaning mechanism, the sampling efficiency is improved and the airflow stability is optimized. At the same time, the cleaning mechanism in the outlet pipe can clean the surfaces of the first and second condensing lenses, avoiding the impact of impurities in the airflow being deposited on the mirror surfaces, which would affect the accuracy of the detection. Regular cleaning improves the accuracy of the detection results. The cleaning mechanism can quickly remove impurities deposited on the surfaces of the first and second condenser lenses, preventing impurities from affecting the accuracy of the detection and improving the accuracy of the detection results. At the same time, it can also dynamically clean or replace the flexible brushes, ensuring the long-term stable impurity removal effect of the cleaning mechanism and maintaining the long-term stable optical structure measurement accuracy, stability and sustainability of the system. The linkage component avoids the need for a separate power source for each rotating axis, reducing the number of power sources, saving the space required to install power sources, and making the entire cleaning mechanism more compact. When cleaning the first and second condensing lenses, a flexible brush scrapes off the impurities on the lens surface. At this time, the negative pressure fan in the moving base starts, and the negative pressure generated will draw the scraped impurities into the dust collection box with a filter screen through the dust collection channel. Air is discharged from the filter screen holes on the dust collection box, while the impurities are collected in the dust collection box to avoid the impurities re-attaching to the lens surface and causing secondary pollution. When the winding drum rotates, the first traction rope will drive the moving seat to move along the guide rail to the side closer to or further away from the irradiation cavity; this facilitates the cleaning mechanism to reach the first and second condensing lens surfaces for cleaning operations, or to move the moving seat to the outside of the air outlet pipe to clean or replace the flexible brush, ensuring the cleanliness of the first and second condensing lens surfaces. When the rotating base rotates, the counterweight in the extended reset assembly uses centrifugal force to move the extended cleaning arm away from the rotating base, covering the entire mirror surface. After cleaning, the reset spring pulls the extended cleaning arm to move back to the side closer to the rotating base for easy cleaning next time. The side of the counterweight away from the extended cleaning arm is tapered, which matches the taper of the light-inlet tapered hole or the reflective tapered hole, making it less likely for the flexible brush to leave dead corners when cleaning the mirror surface, thus improving the cleaning effect. The backflush valve on the backflush pipe can be opened at regular intervals, and the connected air blowing device blows air into the air inlet pipe to clean the impurities that have accumulated in the air extraction hole over time. The cleaning air path can dynamically clean the measuring structure and maintain the accuracy of the system's optical structure measurement to the greatest extent. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the gas path system for automatic analysis of single-particle light scattering particulate matter in an embodiment of this application; Figure 2 This is a schematic diagram showing the structure of the scattered light detection structure; Figure 3 This is a cross-sectional view showing the structure for detecting scattered light; Figure 4 This is a schematic diagram showing the structure of an automated gas path system for analyzing single-particle light-scattering particulate matter from another perspective; Figure 5 This is a structural diagram showing the positional relationship between the air intake pipe, air outlet pipe, and slow-flow pipe. Figure 6 This is a structural schematic diagram showing the positional relationship between the air intake pipe, air outlet pipe, and slow-flow pipe from another perspective. Figure 7 This is a schematic diagram showing the structure when the movable seat moves into the irradiation cavity; Figure 8 This is an exploded view of the filter assembly. Figure 9 It means Figure 8 A magnified schematic diagram of part A in the middle section; Figure 10 This is a schematic diagram showing a partial structure of the cleaning mechanism; Figure 11 This is a schematic diagram showing the internal structure of the movable seat; Figure 12This is a structural diagram showing the rotating base, the extended cleaning arm, the supporting cleaning arm, and the flexible brush located inside the movable base. Figure 13 This is a structural diagram showing the rotating base, extended cleaning arm, supporting cleaning arm, and flexible brush located outside the movable base; Figure 14 This is a schematic diagram showing the structure when the flexible brush is separated from the first connecting seat, the second connecting seat, and the third connecting seat.

[0027] Explanation of reference numerals in the attached drawings: 1. Chassis; 2. Main body shell; 21. Light entrance channel; 211. First condensing lens; 22. Reflection channel; 221. Second condensing lens; 23. Detection channel; 24. Connecting block; 241. Irradiation cavity; 242. Reflecting surface; 243. Light entrance cone aperture; 244. Reflection cone aperture; 25. Illumination device; 3. Reflection assembly; 31. Fixing base; 32. Reflector; 4. Air inlet pipe; 5. Air outlet pipe; 6. Slow-flow pipe; 61. Flow meter; 62. Laminar flow buffer connector; 63. Proportional valve; 7. Filter assembly; 71. Filter chamber; 72. End cap; 73. Filter bracket; 74. Filter membrane; 8. Cleaning mechanism; 81. Guide rail; 82. Moving base; 821. Dust collection channel; 822. Storage slot; 83. Rotating shaft; 84. Electric telescopic rod; 8 5. Rotating seat; 851. Extended cleaning arm; 852. Support cleaning arm; 853. Flexible brush; 854. First connecting seat; 855. Second connecting seat; 856. Third connecting seat; 857. First rubber sleeve; 858. Second rubber sleeve; 859. Third rubber sleeve; 86. Extended reset assembly; 861. Counterweight; 862. Reset spring; 87. Moving assembly; 871. Support frame; 872. Winding spool; 873. First traction rope; 874. Second traction rope; 88. Linkage assembly; 881. Drive motor; 882. Drive bevel gear; 883. Linkage shaft; 884. First transmission bevel gear; 885. Second transmission bevel gear; 886. Driven bevel gear; 89. Negative pressure fan; 891. Dust filter box; 9. Backflush pipe; 91. Backflush valve; 92. Air blowing device. Detailed Implementation

[0028] The following is in conjunction with the appendix Figures 1-14 This application will be described in further detail.

[0029] This application discloses an automated gas path system for analyzing single-particle light-scattering particulate matter. (Refer to...) Figures 1-3The automatic gas path system for single-particle light scattering particulate matter analysis includes a housing 1 and a light scattering detection structure. Specifically, the light scattering detection structure includes a main housing 2 fixed inside the housing 1, an incident light channel 21, a reflection channel 22, and a detection channel 23 sequentially arranged inside the main housing 2, a reflection component 3 located between the detection channel 23 and the reflection channel 22, a connecting block 24 located inside the main housing 2, and an irradiation cavity 241 located inside the connecting block 24. The main housing 2 is the foundation of the entire light scattering detection structure. The reflection channel 22 is located between the incident light channel 21 and the detection channel 23. An illumination device 25 is provided inside the incident light channel 21, which illuminates the airflow to be detected in the irradiation cavity 241, causing the particles in the airflow to emit scattered light. The detection channel 23 is configured to receive and detect the scattered light from the particles. A reflective surface 242 is provided inside the connecting block 24, located on the inner wall of the irradiation cavity 241 on the side opposite to the reflection channel 22.

[0030] Reference Figures 3-6 The main casing 2 has an air inlet pipe 4 and an air outlet pipe 5 connected to the irradiation chamber 241. The air inlet pipe 4 introduces the airflow to be tested into the irradiation chamber 241, and the air outlet pipe 5 discharges the airflow. Inside the casing 1, there is also a slow-flow pipe 6 connected to the air outlet pipe 5, which buffers the airflow. A filter assembly 7 for filtering impurities in the airflow to be tested is installed between the air outlet pipe 5 and the slow-flow pipe 6. The slow-flow pipe 6 is also equipped with a flow meter 61, a laminar flow buffer connector 62, a proportional valve 63, and a suction pump. The flow meter 61 measures the airflow rate; a turbine flow meter 61, electromagnetic flow meter 61, etc., can be used to measure the airflow rate in real time for precise airflow control. The laminar flow buffer connector 62 converts turbulent gas flow into laminar flow, making the airflow more stable and reducing the impact of airflow disturbance on the test results. The proportional valve 63 can precisely adjust the airflow rate as needed, influencing the airflow at the front end by controlling the airflow at the rear end, ensuring the accuracy of the air intake. The suction pump provides airflow power to the entire gas path system, enabling the airflow to be tested to pass smoothly through the gas path. For example, when the concentration of particulate matter in the detection environment is high, the airflow rate can be appropriately increased through the proportional valve 63. In actual operation, after the suction pump is started, the airflow to be tested is drawn into the gas path system, passes through the filter component 7, and enters the slow-flow pipe 6. The flow meter 61 monitors the airflow rate data in real time and feeds it back to the control system. The control system adjusts the airflow rate through the proportional valve 63 according to preset parameters. The laminar flow buffer joint 62 converts the unstable turbulence into stable laminar flow, ensuring that the airflow is stably delivered to the scattered light detection structure for detection.

[0031] Reference Figure 3The illumination cavity 241 is the area through which the airflow to be detected passes, and it is also where light is irradiated and particle scattering light is generated. Specifically, the reflective component 3 includes a fixing base 31 and a reflector 32. The fixing base 31 is assembled inside the reflective channel 22, and the reflector 32 is assembled on the fixing base 31 and is inclined at 45° along the light incident direction. The connecting block 24 has an incident light conical hole 243 inside, and the incident light channel 21 communicates with the illumination cavity 241 through the incident light conical hole 243. A first condensing lens 211 is fixed at one end of the incident light channel 21 near the incident light conical hole 243. The first condensing lens 211 is a convex lens, which can focus the illumination light onto the airflow to be detected in the illumination cavity 241, thereby enhancing the intensity and uniformity of the light. The connecting block 24 also has a reflective conical hole 244 inside. The reflective channel 22 is connected to the irradiation cavity 241 through the reflective conical hole 244. A second condensing lens 221 is fixed at one end of the reflective channel 22 near the reflective conical hole 244. The second condensing lens 221 also serves to focus the light, so that the scattered light can be received more accurately by the detection channel 23. In actual operation, when the light emitted by the illumination device 25 passes through the light entrance channel 21 and is focused by the first condensing lens 211 onto the airflow to be detected in the irradiation cavity 241, the particles in the airflow will emit scattered light. The scattered light is focused by the second condensing lens 221 in the reflective channel 22 and enters the detection channel 23 for detection. The reflective component 3 ensures that the light can propagate along the predetermined path, ensuring the accuracy of the detection.

[0032] Reference Figure 6 and Figure 7 The exhaust pipe 5 is equipped with a cleaning mechanism 8 for cleaning the surfaces of the first condenser lens 211 and the second condenser lens 221. The cleaning mechanism 8 can promptly remove impurities from the condenser lenses, preventing them from interfering with the test results. A backflush pipe 9 is also provided between the intake pipe 4 and the casing 1. The backflush pipe 9 is equipped with a backflush valve 91. One end of the backflush pipe 9 is connected to a blowing device 92, and the other end is connected to the intake pipe 4. The backflush valve 91 can be opened periodically to clean impurities that have accumulated on the pipe wall of the intake pipe 4 over time, ensuring unobstructed airflow. When the backflush valve 91 is opened periodically, the blowing device 92 blows air into the intake pipe 4, expelling accumulated impurities and preventing them from accumulating at the air inlet and affecting airflow.

[0033] Specifically, refer to Figure 5 , Figure 6 and Figure 8The filter assembly 7 includes a filter chamber 71, an end cap 72, a filter support 73, and a filter membrane 74. The filter chamber 71 is fixed to the outside of the housing 1 and is connected to both the outlet pipe 5 and the slow-flow pipe 6. The end cap 72 is threaded onto the outside of the filter chamber 71, facilitating easy opening for replacement and cleaning of the filter membrane 74. The filter support 73 is fixed to the inner wall of the filter chamber 71 and is used to hold the filter membrane 74. The filter membrane 74 filters out impurities in the airflow, ensuring that the airflow entering the slow-flow pipe 6 is relatively clean. When the airflow to be tested flows into the filter chamber 71 from the outlet pipe 5, impurities in the airflow are intercepted by the filter membrane 74, while the clean airflow continues to flow through the slow-flow pipe 6, preventing impurities from entering subsequent air path components and affecting the normal operation of the equipment. This also extends the service life of other components and reduces maintenance costs. When it is necessary to replace the filter membrane 74, the end cap 72 can be opened for operation.

[0034] Specifically, refer to Figure 3 as well as Figures 7-11 The cleaning mechanism 8 includes a guide rail 81, a movable seat 82, two vertically arranged rotating shafts 83, an electric telescopic rod 84, a rotating seat 85, an extension and reset assembly 86, a moving assembly 87, and a linkage assembly 88. The guide rail 81 is fixed inside the air outlet pipe 5 and extends in the same direction as the air outlet pipe 5, providing guidance for the movement of the movable seat 82. The movable seat 82 is slidably connected to the guide rail 81 and can move along the guide rail 81 within the air outlet pipe 5. The rotating shafts 83 are rotatably connected inside the movable seat 82, with one axis of the rotating shaft 83 perpendicular to the surface of the first condenser lens 211 and the other axis perpendicular to the surface of the second condenser lens 221. The electric telescopic rod 84 is fixed to the end of the rotating shaft 83 and is used to adjust the distance between the rotating seat 85 and the condenser lens. A rotating base 85 is fixed to the output end of an electric telescopic rod 84. A rotating shaft 83 has multiple extended cleaning arms 851 arranged circumferentially around it. A supporting cleaning arm 852 is provided between the extended cleaning arms 851 and the rotating base 85. The supporting cleaning arm 852 is fixed to the rotating base 85 and slidably connected to the extended cleaning arms 851. Flexible brushes 853 are provided on the side of the rotating base 85, the supporting cleaning arm 852, and the extended cleaning arm 851 facing away from the electric telescopic rod 84. The flexible brushes 853 are used to clean the surface of the condenser lens.

[0035] Reference Figures 11-14An extended reset assembly 86 is disposed between the extended cleaning arm 851 and the rotating seat 85, and is used to drive the extended cleaning arm 851 to move towards or away from the rotating seat 85; it includes a counterweight 861 and a reset spring 862. The counterweight 861 is fixed to the end of the extended cleaning arm 851 away from the rotating seat 85, and its side away from the extended cleaning arm 851 is set with a conical surface. The conical surface setting makes the counterweight 861 compatible with the taper of the light-incident conical hole 243 or the reflective conical hole 244, so that when the flexible brush 853 cleans the mirror surface of the first condensing lens 211 or the second condensing lens 221, it is not easy to leave dead corners. The return spring 862 is fixed between the extended cleaning arm 851 and the rotating seat 85. When the rotating seat 85 rotates to clean the mirror surface of the first condenser lens 211 and the second condenser lens 221, the counterweight 861 drives the extended cleaning arm 851 to move away from the rotating seat 85 under the action of centrifugal force, thereby covering the entire mirror surface of the first condenser lens 211 or the second condenser lens 221. After cleaning is completed and the rotating shaft 83 stops rotating, the return spring 862 pulls the extended cleaning arm 851 to move closer to the rotating seat 85 to reset, so that the extended cleaning arm 851 retracts, making it easier for the extended cleaning arm 851 to pass through the light-entry cone hole 243 or the reflection cone hole 244 and be stored in the moving seat 82.

[0036] Reference Figure 11 The linkage assembly 88 includes a drive motor 881 and a drive bevel gear 882. The drive motor 881 is fixed inside the movable base 82, and the drive bevel gear 882 is fixedly sleeved on the output shaft of the drive motor 881. Two linkage shafts 883 are also rotatably connected inside the movable base 82. A first transmission bevel gear 884 and a second transmission bevel gear 885 are fixedly sleeved at both ends of the linkage shaft 883, respectively. The first transmission bevel gear 884 meshes with the drive bevel gear 882. A driven bevel gear 886 is fixedly sleeved on the outside of the rotating shaft 83, and the second transmission bevel gear 885 meshes with the driven bevel gear 886. When the drive motor 881 starts, it drives the two rotating shafts 83 to rotate synchronously through the drive bevel gear 882, linkage shaft 883, first transmission bevel gear 884, second transmission bevel gear 885 and driven bevel gear 886, so as to achieve synchronous cleaning of the two condenser lenses. The linkage component 88 avoids setting a separate power source for each rotating shaft 83, reduces the number of power sources, saves the space required to install the power sources, and makes the structure of the entire cleaning mechanism 8 more compact.

[0037] Reference Figures 7-9The movable component 87 includes a support frame 871 and a winding drum 872. The support frame 871 is located at the end of the air outlet pipe 5 and fixed to the inner wall of the filter chamber 71. The winding drum 872 is rotatably connected to the support frame 871. A first traction rope 873 and a second traction rope 874 are wound on the winding drum 872 respectively. The first traction rope 873 and the second traction rope 874 are wound in opposite directions. Both the first traction rope 873 and the second traction rope 874 are connected to the movable seat 82. When the winding drum 872 rotates in the forward direction, the first traction rope 873 drives the movable seat 82 to move along the guide rail 81 towards the side closer to the irradiation chamber 241. When the winding drum 872 rotates in the reverse direction, the second traction rope 874 drives the movable seat 82 to move along the guide rail 81 away from the irradiation chamber 241.

[0038] In addition, refer to Figures 11-14 The rotating base 85, the supporting cleaning arm 852, and the extended cleaning arm 851 are respectively fixed with a first connecting base 854, a second connecting base 855, and a third connecting base 856 on the side away from the electric telescopic rod 84. The first connecting base 854, the second connecting base 855, and the third connecting base 856 are respectively fitted with a first rubber sleeve 857, a second rubber sleeve 858, and a third rubber sleeve 859. A flexible brush 853 is fixed to the outside of the first rubber sleeve 857, the second rubber sleeve 858, and the third rubber sleeve 859. The rubber sleeves have a certain degree of flexibility and elasticity. When the brush needs to be removed for cleaning or replaced due to wear and aging after a certain period of use, it can be quickly removed through the rubber sleeve, which improves the convenience of removing or replacing the flexible brush 853. The movable base 82 is equipped with a negative pressure fan 89. A dust collection channel 821 is located on one side of the movable base 82 extending from the negative pressure fan 89 to the side of the movable base 82. A dust filter box 891 with a filter screen is located on the side of the negative pressure fan 89 away from the dust collection channel 821. A storage slot 822 adapted to the dust filter box 891 is located within the storage slot 822, and the dust filter box 891 and the storage slot 822 are magnetically attracted to each other. The negative pressure fan 89 uses a flexible brush 853 to draw impurities removed from the surface of the first focusing lens 211 or the second focusing lens 221 into the dust collection channel 821 via negative pressure, and then collects them in the dust filter box 891. Air is discharged from the filter screen holes on the dust filter box 891, while impurities remain in the dust filter box 891 for collection.

[0039] When the cleaning mechanism 8 is working, the winding drum 872 of the moving component 87 first rotates, driving the moving seat 82 along the guide rail 81 towards the side closer to the irradiation cavity 241 via the first traction rope 873, so that the two rotating seats 85 are respectively aligned with the light-receiving conical hole 243 or the reflecting conical hole 244. Then, the electric telescopic rod 84 extends, bringing the rotating seat 85 closer to the condensing lens until the flexible brush 853 abuts against the first condensing lens 211 or the second condensing lens 221. Then, the drive motor 881 starts, driving the two rotating shafts 83 to rotate synchronously via the linkage component 88. When the rotating shafts 83 rotate, the extended cleaning arm 851 extends outward under the action of centrifugal force, overcoming the tension of the return spring 862, so that the flexible brush 853 covers the condensing lens surface for cleaning. During the cleaning process, the negative pressure fan 89 inside the moving seat 82 starts, sucking the impurities cleaned by the brush into the dust collection box 891 through the dust collection channel 821. After cleaning is completed, the drive motor 881 stops, the extended cleaning arm 851 resets under the action of the return spring 862, the electric telescopic rod 84 retracts, and the movable seat 82 returns to its initial position under the action of the movable component 87.

[0040] The implementation principle of the automatic gas path system for single-particle light scattering particulate matter analysis according to an embodiment of this application is as follows: An air pump is activated to provide airflow power. The airflow to be detected enters through the inlet pipe 4. After entering the irradiation chamber 241, the light emitted by the illumination device 25 is focused onto the airflow through the light entrance channel 21 and the first condenser lens 211, causing the particles to scatter light. The scattered light is focused by the second condenser lens 221 and then reflected by the reflection channel 22 and the reflection component 3 to the detection channel 23, where it is detected. When the airflow exits from the outlet pipe 5, it first passes through the filter component 7, where the filter membrane 74 intercepts impurities in the airflow. The airflow then enters the slow-flow pipe 6. In the slow-flow pipe 6, the flow meter 61 monitors the airflow flow rate in real time, the laminar flow buffer connector 62 converts the turbulent flow of the airflow into laminar flow, and the proportional valve 63 controls the front-end airflow according to the downstream flow rate, ensuring accurate and stable air intake. During system operation, the cleaning mechanism 8 periodically cleans the surfaces of the first condenser lens 211 and the second condenser lens 221 to prevent impurities from affecting the detection accuracy. This automatic gas path system for single-particle light scattering particulate matter analysis can achieve accurate analysis of particulate matter. Through the coordinated work of components such as the filter assembly 7, the slow-flow pipe 6, and the cleaning mechanism 8, sampling efficiency is improved and airflow stability is optimized. At the same time, the cleaning mechanism 8 in the outlet pipe 5 can clean the surfaces of the first condenser lens 211 and the second condenser lens 221, avoiding the impact on the accuracy of detection due to the adhesion and deposition of impurities in the gas flow to be detected on the mirror surfaces. Regular cleaning improves the accuracy of the detection results.

[0041] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An automated gas path system for analyzing single-particle light-scattering particulate matter, characterized in that, include: A chassis (1) is provided with a light scattering detection structure inside the chassis (1); The astigmatism detection structure includes a main body shell (2) fixed inside the chassis (1). The main body shell (2) has an entrance light channel (21) and a detection channel (23) inside. A reflection channel (22) is also provided between the entrance light channel (21) and the detection channel (23). A reflection component (3) is provided between the detection channel (23) and the reflection channel (22). The main body shell (2) has a connecting block (24) inside, and an irradiation chamber (241) is opened inside the connecting block (24); the main body shell (2) has an air inlet pipe (4) and an air outlet pipe (5) communicating with the irradiation chamber (241) on the outside; the chassis (1) also has a slow flow pipe (6) communicating with the air outlet pipe (5), and a filter assembly (7) for filtering impurities in the airflow to be detected is provided between the air outlet pipe (5) and the slow flow pipe (6); the slow flow pipe (6) is also provided with a flow meter (61), a laminar flow buffer connector (62), a proportional valve (63) and a vacuum pump in sequence; The connecting block (24) has an entrance light cone hole (243) inside. The irradiation cavity (241) is connected to the entrance light channel (21) through the entrance light cone hole (243). A first condensing lens (211) is fixed at one end of the entrance light channel (21) near the entrance light cone hole (243). The connecting block (24) has a reflective conical hole (244) inside. The irradiation cavity (241) is connected to the reflective channel (22) through the reflective conical hole (244). A second condensing lens (221) is fixed at one end of the reflective channel (22) near the reflective conical hole (244). The air outlet pipe (5) is equipped with a cleaning mechanism (8) for cleaning the mirror surfaces of the first condenser lens (211) and the second condenser lens (221).

2. The automatic gas path system for single-particle light scattering particulate matter analysis according to claim 1, characterized in that, The cleaning mechanism (8) includes: The guide rail (81) is fixed inside the air outlet pipe (5) and is aligned with the extension direction of the air outlet pipe (5); The movable seat (82) is slidably connected to the guide rail (81); Two vertically arranged rotating shafts (83) are rotatably connected to the movable seat (82), one of the rotating shafts (83) having its axis perpendicular to the surface of the first condenser lens (211) and the other rotating shaft (83) having its axis perpendicular to the surface of the second condenser lens (221). An electric telescopic rod (84) is fixed to the end of the rotating shaft (83); A rotating base (85) is fixed to the output end of the electric telescopic rod (84). The rotating shaft (83) is provided with a plurality of extended cleaning arms (851) along its circumference. A supporting cleaning arm (852) is provided between the extended cleaning arm (851) and the rotating base (85). The supporting cleaning arm (852) is fixed to the rotating base (85), and the supporting cleaning arm (852) is slidably connected to the extended cleaning arm (851). A flexible brush (853) is provided on the side of the rotating base (85), the supporting cleaning arm (852), and the extended cleaning arm (851) away from the electric telescopic rod (84). An extension reset assembly (86) is disposed between the extension cleaning arm (851) and the rotating seat (85) for driving the extension cleaning arm (851) to move toward or away from the rotating seat (85). A movable component (87) is located at the end of the air outlet pipe (5) and is used to drive the movable seat (82) to move along the extension path of the air outlet pipe (5); A linkage component (88) is disposed between the two rotating shafts (83) for driving the two rotating shafts (83) to rotate synchronously.

3. The automatic gas path system for single-particle light scattering particulate matter analysis according to claim 2, characterized in that, The linkage component (88) includes: A drive motor (881) is fixed inside the movable base (82); A drive bevel gear (882) is fixedly sleeved on the output shaft of the drive motor (881). Two linkage shafts (883) are also rotatably connected inside the movable seat (82). A first transmission bevel gear (884) and a second transmission bevel gear (885) are fixedly sleeved at both ends of the linkage shaft (883). The first transmission bevel gear (884) meshes with the drive bevel gear (882). The driven bevel gear (886) is fixedly sleeved on the outside of the rotating shaft (83), and the second transmission bevel gear (885) meshes with the driven bevel gear (886).

4. The automatic gas path system for single-particle light scattering particulate matter analysis according to claim 2, characterized in that, The extended reset assembly (86) includes: A counterweight (861) is fixed to one end of the extended cleaning arm (851) away from the rotating seat (85); A return spring (862) is fixed between the extended cleaning arm (851) and the rotating seat (85) to drive the extended cleaning arm (851) to move closer to the rotating seat (85).

5. The automatic gas path system for single-particle light scattering particulate matter analysis according to claim 4, characterized in that, The counterweight (861) is tapered on the side away from the extended cleaning arm (851).

6. The automatic gas path system for single-particle light scattering particulate matter analysis according to claim 2, characterized in that, The rotating base (85), the supporting cleaning arm (852), and the extended cleaning arm (851) are respectively fixed with a first connecting seat (854), a second connecting seat (855), and a third connecting seat (856) on the side away from the electric telescopic rod (84). The first connecting seat (854), the second connecting seat (855), and the third connecting seat (856) are respectively fitted with a first rubber sleeve (857), a second rubber sleeve (858), and a third rubber sleeve (859). A flexible brush (853) is fixed to the outside of the first rubber sleeve (857), the second rubber sleeve (858), and the third rubber sleeve (859).

7. The automatic gas path system for single-particle light scattering particulate matter analysis according to claim 2, characterized in that, The movable seat (82) is equipped with a negative pressure fan (89). A dust collection channel (821) is provided on one side of the movable seat (82) extending from the negative pressure fan (89) to the movable seat (82). A dust filter box (891) with a filter screen is provided on the side of the negative pressure fan (89) away from the dust collection channel (821). A storage slot (822) adapted to the dust filter box (891) is provided in the movable seat (82). The dust filter box (891) is located in the storage slot (822).

8. The automatic gas path system for single-particle light scattering particulate matter analysis according to claim 2, characterized in that, The filter assembly (7) includes a filter chamber (71) fixed to the outside of the chassis (1) and an end cap (72) threaded to the outside of the filter chamber (71). The filter chamber (71) is connected to both the air outlet pipe (5) and the slow flow pipe (6). A filter support (73) fixed to the inner wall of the filter chamber (71) and a filter screen (74) placed on the filter support (73) are also provided between the air outlet pipe (5) and the slow flow pipe (6).

9. The automatic gas path system for single-particle light scattering particulate matter analysis according to claim 8, characterized in that, The moving component (87) includes: A support frame (871) is provided at the end of the air outlet pipe (5) and fixed to the inner wall of the filter chamber (71); A winding spool (872) is rotatably connected to the support frame (871). A first traction rope (873) and a second traction rope (874) are wound on the winding spool (872). The first traction rope (873) and the second traction rope (874) are wound in opposite directions. Both the first traction rope (873) and the second traction rope (874) are connected to the movable seat (82).

10. An automated gas path system for analyzing single-particle light-scattering particulate matter according to any one of claims 1-9, characterized in that, A backflush pipe (9) is also provided between the air intake pipe (4) and the chassis (1). A backflush valve (91) is provided on the backflush pipe (9). One end of the backflush pipe (9) is connected to the air blowing device (92), and the other end is connected to the air intake pipe (4).

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