Atmospheric particulate matter online monitoring device

Abstract

The present invention relates to the technical field of automatic atmospheric monitoring equipment, and proposes an online atmospheric particulate matter monitoring device, including a bracket; a filter paper belt is arranged on the bracket; an air extraction mechanism is arranged on the bracket and has a nozzle, the nozzle moves to press the filter paper belt, and the gas ejected from the nozzle passes through the filter paper belt and forms a detection area on the filter paper belt; a β-ray source is slidably arranged on the bracket and is located on one side of the detection area, and the β-ray source slides to the detection area and emits β-rays to the detection area; a β-ray detector is arranged on the other side of the detection area and is used to detect β-rays that pass through the detection area. Through the above technical scheme, the problem of deviation in detection results in devices based on β-ray absorption method in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of automatic atmosphere monitoring equipment, and in particular to an online monitoring device for atmospheric particulate matter. Background Art

[0002] The atmospheric environment has a vital impact on people's lives and health, so it is particularly important to monitor particulate matter in the atmospheric environment. Atmospheric particulate matter is a general term for solid or liquid particulate matter dispersed in the atmosphere. Atmospheric particulate matter with a particle size of 0.01μm to 100μm is collectively referred to as total suspended particulate matter TSP. PM10 and PM2.5 refer to atmospheric particulate matter with an aerodynamic diameter less than or equal to 10μm and 2.5μm, respectively. PM10 is also called inhalable particulate matter, and the World Health Organization (WHO) calls it particulate matter that can enter the chest; PM2.5 can enter the human alveoli and is called respirable particulate matter. At present, the automatic monitoring methods of atmospheric particulate matter are: β-ray absorption method, micro-oscillation balance method, and light scattering method. The β-ray absorption method mainly calculates the mass concentration of particulate matter by measuring the loss of rays passing through the filter paper with particulate matter attached. There are three main structures of existing devices based on the beta-ray absorption method. In structure one, the beta source, detector and air intake pipe are in a straight line. The beta source is fixed in the air intake pipe. The sampling airflow passes through the beta source and reaches the filter paper belt vertically. The concentration of particulate matter is calculated by measuring the count values ​​before and after sampling. This structure will cause the particles to gather in the outer circle of the sampling spot when measuring large particles (PM10 or TSP). There are fewer particles gathered in the center of the spot, and the formed spots are uneven, resulting in low particle measurement values. In structure two, the beta source and detector are fixed on one side of the sampling pipe. The sampling airflow reaches the filter paper belt vertically. The count values ​​before and after sampling are measured by the two-way movement of the filter paper belt. The concentration of particulate matter is calculated by the counting value after sampling. This structure has complex control functions and high costs. In structure three, the air inlet takes in air from one side, and the beta source and detector are placed on both sides of the air inlet. The sampling airflow reaches the filter paper tape at a certain angle, and the concentration of particulate matter is calculated by measuring the counting values ​​before and after sampling. This structure will cause the particles to gather on the side of the sampling spot away from the air inlet when measuring large particles (PM10 or TSP). There are fewer particles gathered in the center of the spot and on the side close to the air inlet, and the spots formed on the paper tape are uneven. At the same time, the pipe elbow will cause accumulation of particles, and the particles in the sampling airflow cannot all reach the filter paper tape, resulting in low particle measurement values. Summary of the invention

[0003] The present invention provides an online monitoring device for atmospheric particulate matter, which solves the problem of deviation in detection results in devices based on the beta-ray absorption method in the prior art.

[0004] The technical solution of the present invention is as follows:

[0005] Atmospheric particulate matter online monitoring device, including:

[0006] Bracket;

[0007] A supporting platform, arranged on the bracket;

[0008] A filter paper belt is arranged on the supporting platform;

[0009] An air extraction mechanism is arranged on the support and has a nozzle, the nozzle moves to press the filter paper belt, and the gas ejected from the nozzle passes through the filter paper belt and forms a detection area on the filter paper belt;

[0010] a beta ray source, slidably disposed on the bracket and located at one side of the detection area, wherein the beta ray source emits beta rays toward the detection area after sliding to the detection area; and

[0011] The β-ray detector is disposed at the other side of the detection area and is used to detect the β-rays passing through the detection area.

[0012] As a further technical solution, it also includes an air suction nozzle, which is arranged on the supporting platform. The supporting platform is provided with an air vent, and the air suction nozzle is connected to the nozzle via the air vent.

[0013] As a further technical solution, the support platform is further provided with a mounting hole, the mounting hole is communicated with the air vent, and the beta-ray detector is arranged in the mounting hole.

[0014] As a further technical solution, it also includes a sliding frame, which is slidably arranged on the supporting platform, and the beta ray source is arranged on the sliding frame.

[0015] As a further technical solution, the bracket has a through hole, and the sliding frame includes:

[0016] A slide rod is slidably disposed on the support platform, the slide rod passes through the through hole, and a threaded hole is formed at the end of the slide rod;

[0017] A lead screw is rotatably mounted on the bracket and passes through the threaded hole; and

[0018] The motor is arranged on the bracket, and the output end of the motor is connected to the lead screw.

[0019] As a further technical solution, a filter paper feeding mechanism is also included, and the filter paper feeding mechanism includes:

[0020] A filter paper roll is rotatably mounted on the support; and

[0021] The paper feeding mechanism is arranged on the support and is used for conveying the filter paper tape of the filter paper tape roll.

[0022] As a further technical solution, the paper feeding mechanism includes:

[0023] A driving shaft is rotatably arranged on the bracket, and the unwinding end of the filter paper tape roll is wound around the driving shaft;

[0024] A driven shaft is rotatably mounted on the bracket, and the filter paper belt is rolled and sleeved on the driven shaft; and

[0025] A guide shaft is rotatably disposed on the bracket and is used to guide the filter paper belt.

[0026] As a further technical solution, the air extraction mechanism further comprises:

[0027] A connecting plate, arranged on the bracket and located above the supporting platform;

[0028] a telescopic tube, which is passed through the connecting plate, both ends of the telescopic tube pass through the connecting plate, and the nozzle is disposed at the lower end of the telescopic tube; and

[0029] A driving assembly is arranged on the bracket and is used for driving the telescopic tube to extend and retract.

[0030] As a further technical solution, the air extraction mechanism further comprises:

[0031] A protrusion provided on the telescopic tube; and

[0032] The spring is sleeved outside the telescopic tube, with one end abutting against the connecting plate and the other end abutting against the protrusion.

[0033] As a further technical solution, the driving assembly includes:

[0034] A rotating shaft rotatably disposed on the bracket; and

[0035] The cam is arranged on the rotating shaft and contacts the protrusion.

[0036] The working principle and beneficial effects of the present invention are as follows: compared with the prior art, the support platform is fixedly arranged on the bracket, the filter paper tape is placed on the support platform, the support platform can support the filter paper tape, the nozzle in the exhaust mechanism can be moved, the nozzle is moved up, the beta source is moved to the measurement area, the blank filter paper is counted, and after the counting is completed, the beta source is removed, the nozzle is moved down to press the filter paper tape to start sampling, the sample gas reaches the filter paper tape vertically through the nozzle, when the gas passes through the filter paper tape, the particulate matter in the sampled gas will be filtered on the filter paper tape to form uniform spots; after the sampling is completed, the nozzle is removed, and then the beta ray source is moved to the top of the spot, and the particulate matter in the detection area can be detected by counting twice. The atmospheric particulate matter online monitoring device provided by the present invention has a simple structure, and the sampling spots formed on the paper tape are uniform, which ensures the accuracy of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0038] Figure 1 It is an isometric structural schematic diagram of the online monitoring device for atmospheric particulate matter provided by the present invention;

[0039] Figure 2 for Figure 1 The main view of

[0040] Figure 3 for Figure 1 A schematic diagram of a partial structure of

[0041] Figure 4 for Figure 1 Schematic diagram of the structure from another angle;

[0042] Figure 5 A cross-sectional view of the support platform.

[0043] In the figure:

[0044] 1. Bracket; 2. Filter paper belt; 3. Air extraction mechanism; 4. β-ray source; 5. β-ray detector; 6. Support platform; 7. Sliding rack; 8. Filter paper feeding mechanism; 9. Air extraction nozzle;

[0045] 11. through hole; 31. nozzle; 32. connecting plate; 33. telescopic tube; 34. protrusion; 35. spring; 36. rotating shaft; 37. cam; 61. air hole; 62. mounting hole; 71. slide rod; 72. lead screw; 73. motor; 81. filter paper roll; 82. paper feeding mechanism;

[0046] 821, driving shaft; 822, driven shaft; 823, guide shaft. DETAILED DESCRIPTION

[0047] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] like Figures 1 to 5As shown, the online monitoring device for atmospheric particulate matter proposed by the present invention includes a bracket 1, a filter paper belt 2, an exhaust mechanism 3, a β-ray source 4, a β-ray detector 5 and a support platform 6; the support platform 6 is arranged on the bracket 1; the filter paper belt 2 is arranged on the support platform 6; the exhaust mechanism 3 is arranged on the bracket 1 and has a nozzle 31, the nozzle 31 presses the filter paper belt 2 after moving, and the gas sprayed by the nozzle 31 passes through the filter paper belt 2 and forms a detection area on the filter paper belt 2; the β-ray source 4 is slidably arranged on the bracket 1 and is located at one side of the detection area, and the β-ray source 4 emits β-rays to the detection area after sliding to the detection area; and the β-ray detector 5 is arranged on the other side of the detection area and is used to detect the β-rays passing through the detection area.

[0049] In this embodiment, the support platform 6 is fixedly arranged on the bracket 1, and the filter paper belt 2 is placed on the support platform 6. The support platform 6 can support the filter paper belt 2, and the nozzle 31 in the exhaust mechanism 3 can move. The nozzle 31 can press the filter paper belt 2 by moving, and the gas sprayed from the nozzle 31 passes through the filter paper belt 2. The gas comes from the sampling gas. Therefore, when the sampling gas passes through the filter paper belt 2, the particulate matter in the sampling gas will adhere to the filter paper belt 2; the part of the filter paper belt 2 passed by the sampling gas forms a detection area, and when the sampling is completed, the nozzle 31 is removed, and then the β-ray source 4 is moved to the detection area. The β-ray detector 5 is arranged on the other side of the detection area. When the β-ray source 4 fully irradiates the detection area, the β-ray passing through the detection area is detected by the β-ray detector 5, and the particulate matter in the detection area can be detected by the loss of β-rays. This arrangement improves the detection accuracy of particulate matter in the atmosphere.

[0050] In this embodiment, the nozzle 31 first presses the filter paper belt 2, then starts sampling and forms a detection area on the filter paper belt 2, then removes the nozzle 31 and moves the β-ray source 4 to the detection area, and finally cooperates with the β-ray detector 5 to detect the particulate matter in the detection area.

[0051] As a specific embodiment of the present invention, Figure 3 and Figure 4 As shown, it also includes an air suction nozzle 9, which is arranged on the supporting platform 6. The supporting platform 6 is provided with an air vent 61, and the air suction nozzle 9 is connected to the nozzle 31 via the air vent 61.

[0052] In this embodiment, in order to enable the exhaust mechanism 3 to exhaust air from the atmosphere, an exhaust nozzle 9 can be set. The exhaust nozzle 9 is fixedly set on the supporting platform 6, and an air hole 61 is opened on the supporting platform 6. One end of the air hole 61 is connected to the nozzle 31, and the other end is connected to the exhaust nozzle 9. In this way, the exhaust nozzle 9 can be set on the side of the supporting platform 6, reducing the space occupancy rate.

[0053] As a specific embodiment of the present invention, Figure 1 and Figure 3As shown, the support platform 6 is further provided with a mounting hole 62 , the mounting hole 62 is communicated with the air vent 61 , and the β-ray detector 5 is arranged in the mounting hole 62 .

[0054] In this embodiment, a mounting hole 62 is opened on the supporting platform 6, and the diameter of the mounting hole 62 is larger than the diameter of the air hole 61, and the mounting hole 62 is kept connected with the air hole 61, which can also facilitate the β-ray detector 5 to stably receive β rays.

[0055] As a specific embodiment of the present invention, Figure 1 As shown, it also includes a sliding frame 7, which is slidably arranged on the bracket 1, and the β-ray source 4 is arranged on the sliding frame 7.

[0056] In this embodiment, the β-ray source 4 is implemented on the support platform 6 by means of a sliding frame 7. The sliding frame 7 is slidably arranged on the support platform 6, which facilitates the movement operation of the β-ray source 4 and can accurately realize the operation while reducing the cost.

[0057] As a specific embodiment of the present invention, Figure 2 As shown, the bracket 1 has a through hole 11, and the sliding frame 7 includes:

[0058] A slide bar 71 is slidably disposed on the support platform 6. The slide bar 71 passes through the through hole 11. A threaded hole is formed at the end of the slide bar 71.

[0059] A lead screw 72 is rotatably mounted on the bracket 1 and passes through the threaded hole; and

[0060] The motor 73 is disposed on the bracket 1 , and the output end of the motor 73 is connected to the lead screw 72 .

[0061] In this embodiment, the sliding frame 7 includes a sliding rod 71, a lead screw 72 and a motor 73. The sliding rod 71 passes through the through hole 11 on the bracket 1 and is slidably set on the support platform 6. One end of the sliding rod 71 is used to install and fix the β-ray source 4, and the other end is provided with a threaded hole. The motor 73 is fixedly set on the bracket 1, and the output shaft is connected to the lead screw 72. The lead screw 72 is passed through the threaded hole. When the motor 73 rotates, the lead screw 72 rotates accordingly, thereby pushing the sliding rod 71 to slide on the support platform 6.

[0062] As a specific embodiment of the present invention, Figure 2 As shown, it also includes a filter paper feeding mechanism 8, and the filter paper feeding mechanism 8 includes:

[0063] A filter paper roll 81 is rotatably mounted on the support 1; and

[0064] The paper feeding mechanism 82 is disposed on the bracket 1 and is used to move the filter paper tape 2 of the filter paper tape roll 81 .

[0065] In this embodiment, the filter paper feeding mechanism 8 includes a filter paper roll 81 and a feeding mechanism 82. The filter paper roll 81 is rotatably arranged on the bracket 1, and the feeding mechanism 82 is arranged on the bracket 1. The feeding mechanism 82 is used to unwind the filter paper roll 81.

[0066] As a specific embodiment of the present invention, Figure 1 As shown, the paper feeding mechanism 82 includes:

[0067] A driving shaft 821 is rotatably mounted on the bracket 1, and the unwinding end of the filter paper tape roll 81 is wound around the driving shaft 821;

[0068] A driven shaft 822 is rotatably mounted on the bracket 1, and the filter paper roll 81 is sleeved on the driven shaft 822; and

[0069] The guide shaft 823 is rotatably disposed on the bracket 1 and is used to guide the filter paper belt 2 .

[0070] In this embodiment, a driving shaft 821, a driven shaft 822 and a guide shaft 823 with axes parallel to each other are provided in the paper feeding mechanism 82. The filter paper tape roll 81 is sleeved on the driven shaft 822, and the unwinding end of the filter paper tape roll 81 is wound on the driving shaft 821. The guide shaft 823 guides the running direction of the filter paper tape 2. When the driving shaft 821 is rotated, the filter paper tape 2 starts to be wound from the driven shaft 822 to the driving shaft 821.

[0071] As a specific embodiment of the present invention, Figure 2 As shown, the exhaust mechanism 3 also has a connecting plate 32, a telescopic tube 33 and a driving assembly; the connecting plate 32 is arranged on the bracket 1 and is located above the supporting platform 6; the telescopic tube 33 is passed through the connecting plate 32, and both ends of the telescopic tube 33 pass through the connecting plate 32, and the nozzle 31 is arranged at the lower end of the telescopic tube 33; the driving assembly is arranged on the bracket 1, and is used to drive the telescopic tube 33 to extend and retract.

[0072] In this embodiment, the exhaust mechanism 3 also includes a connecting plate 32, a telescopic tube 33 and a driving assembly. The connecting plate 32 is L-shaped and fixedly arranged on the supporting platform 6. There is a gap between the connecting plate 32 and the supporting platform 6, and the filter paper belt 2 passes through the gap. The telescopic tube 33 is fixedly arranged on the connecting plate 32, and the nozzle 31 is arranged at the bottom end of the telescopic tube 33. The driving assembly can drive the telescopic tube 33 to achieve telescopic expansion and contraction, and finally the nozzle 31 can be pressed on the filter paper belt 2 and can also be separated from the filter paper belt 2.

[0073] Furthermore, the air extraction mechanism 3 also has a protrusion 34 and a spring 35 ; the protrusion 34 is arranged on the telescopic tube 33 ; the spring 35 is sleeved outside the telescopic tube 33 , and one end of the spring abuts against the connecting plate 32 , and the other end abuts against the protrusion 34 .

[0074] In this embodiment, the vacuum mechanism 3 also includes a protrusion 34 and a spring 35. At this time, the telescopic tube 33 is composed of an inner tube and an outer tube. The inner tube is slidably arranged in the outer tube, and the protrusion 34 is arranged on the inner tube. The spring 35 is sleeved on the outside of the telescopic tube 33, and one end abuts on the connecting plate 32, and the other end abuts on the protrusion 34. The driving component can drive the inner tube to slide in the outer tube, and the spring 35 can ensure that the sliding process of the inner tube in the outer tube remains stable.

[0075] Furthermore, the driving assembly includes a rotating shaft 36 and a cam 37 ; the rotating shaft 36 is rotatably disposed on the bracket 1 ; the cam 37 is disposed on the rotating shaft 36 and contacts the protrusion 34 .

[0076] In this embodiment, the driving assembly includes a rotating shaft 36 and a cam 37. One end of the rotating shaft 36 is rotatably set on the bracket 1 and is driven by a motor. The cam 37 is fixedly set at the other end of the rotating shaft 36 and is located below the protrusion 34. The protrusion 34 always keeps in contact with the cam 37. During the rotation of the cam 37, the inner tube slides in the outer tube through the protrusion 34 and returns to the original state with the help of the spring 35.

[0077] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An online monitoring device for atmospheric particulate matter, characterized in that: include: Bracket (1); A supporting platform (6) is arranged on the support (1); A filter paper belt (2) is arranged on the supporting platform (6); an air extraction mechanism (3) disposed on the support (1) and having a nozzle (31); the nozzle (31) moves up and down, and after moving down, presses the filter paper belt (2); an air flow passes vertically through the filter paper belt (2) through the nozzle (31) and forms a detection area on the filter paper belt (2); a beta ray source (4) slidably disposed on the support (1) and located on one side of the detection area, wherein the beta ray source (4) slides to a position just above the detection area and emits beta rays toward the detection area; as well as A beta ray detector (5), arranged at the other side of the detection area and used to detect beta rays passing through the detection area; An air suction nozzle (9), the air suction nozzle (9) being arranged on the supporting platform (6), the supporting platform (6) being provided with an air vent (61), the air suction nozzle (9) being in communication with the nozzle (31) via the air vent (61); The support platform (6) is further provided with a mounting hole (62), the mounting hole (62) being in communication with the air vent (61), and the beta-ray detector (5) being arranged in the mounting hole (62); A sliding frame (7), the sliding frame (7) being slidably disposed on the supporting platform (6), and the beta ray source (4) being disposed on the sliding frame (7); The bracket (1) has a through hole (11), and the sliding frame (7) comprises: A sliding rod (71) is slidably disposed on the supporting platform (6), the sliding rod (71) passes through the through hole (11), and a threaded hole is formed at the end of the sliding rod (71); A lead screw (72) is rotatably mounted on the bracket (1) and passes through the threaded hole; and A motor (73) is disposed on the bracket (1), and an output end of the motor (73) is connected to the lead screw (72); The air extraction mechanism (3) further comprises: A connecting plate (32) is provided on the bracket (1) and is located above the supporting platform (6); a telescopic tube (33) passing through the connecting plate (32), both ends of the telescopic tube (33) passing through the connecting plate (32), and the nozzle (31) being arranged at the lower end of the telescopic tube (33); and A driving assembly, disposed on the support (1), and used for driving the telescopic tube (33) to extend and retract; The air extraction mechanism (3) further comprises: A protrusion (34) is provided on the telescopic tube (33); and A spring (35) is sleeved outside the telescopic tube (33), with one end abutting against the connecting plate (32) and the other end abutting against the protrusion (34); The drive assembly comprises: A rotating shaft (36) rotatably mounted on the bracket (1); and A cam (37) is disposed on the rotating shaft (36) and is in contact with the protrusion (34).

2. The online monitoring device for atmospheric particulate matter according to claim 1, characterized in that: It also includes a filter paper feeding mechanism (8), wherein the filter paper feeding mechanism (8) includes: A filter paper roll (81) is rotatably mounted on the support (1); and A paper feeding mechanism (82) is provided on the support (1) and is used for conveying the filter paper tape (2) of the filter paper tape roll (81).

3. The online monitoring device for atmospheric particulate matter according to claim 2 is characterized in that: The paper feeding mechanism (82) comprises: A driving shaft (821) is rotatably mounted on the bracket (1), and one end of the filter paper tape roll (81) is wound around the driving shaft (821); A driven shaft (822) is rotatably mounted on the bracket (1), and the filter paper tape roll (81) is sleeved on the driven shaft (822); and A guide shaft (823) is rotatably disposed on the bracket (1) and is used to guide the filter paper belt (2).

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