Air pollutant concentration detection device

Abstract

The invention relates to the technical field of air detection, in particular to an air pollutant concentration detection device which comprises a shell, the shell comprises an upper shell body and a lower shell body, a circuit board is arranged between the upper shell body and the lower shell body, a laser detection assembly is arranged on the lower surface of the circuit board, and a channel shaped like a Chinese character'shan 'is formed in the lower shell body. The channel shaped like the Chinese character'shan 'comprises a U-shaped part and a vertical-line-shaped part, pressed parts are arranged at the corners of the U-shaped part, the pressed parts detect the pressure of airflow flowing through the U-shaped part, a piezoelectric air supply assembly is arranged on the outer side of the U-shaped part, and a section regulation and control assembly is arranged on the inner side of the U-shaped part; by arranging the piezoelectric gas supply assembly and the cross section regulation and control assembly, when the piezoelectric gas supply assembly provides power for the cross section regulation and control assembly, the cross section regulation and control assembly deforms in different directions to regulate the cross section of the channel shaped like the Chinese character'shan ', so that dust adhered to the U-shaped part is cleaned, and the detection accuracy of the laser detection assembly is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of air detection, and in particular to a device for detecting air pollutant concentration. Background Art

[0002] During the construction phases of foundation pit excavation and concrete pouring, dust pollution is a significant problem, posing a severe challenge to the adjacent residential environment. In view of this, the implementation of real-time dust concentration monitoring has become a necessary measure, aiming to accurately assess the level of environmental pollution and environmental quality by monitoring various indicators reflecting environmental quality.

[0003] However, existing dust monitoring equipment generally has the problems of simple structural design, single function, lack of flexibility during observation, and difficulty in adjusting the observation angle. Although some equipment has adjustment function, the adjustment process is cumbersome and complicated, and the operation is inconvenient.

[0004] A Chinese patent with application number 202010347332.2 discloses a dust monitoring device for a dust control system, including a base frame, a crossbeam, a load-bearing plate, an adjustment component, an electric control box, a dust shield, a lifting component, a digital display component, a mounting pole, a rack, a dust detector, a solar panel and a supporting base, wherein four crossbeams are fixedly installed on the top end surface of the base frame by welding, and a load-bearing plate is fixedly installed on the top of every two crossbeams by screws, an adjustment component is provided on the top of the load-bearing plate at one side of the top of the base frame, a lifting component is provided on the top of the adjustment component, and a mounting pole is plugged and installed on the top of the lifting component, and a rack is provided on one side of the outer wall of the mounting pole; the dust monitoring device for the dust control system is small in size and easy to install; it can monitor dust with good monitoring effect; at the same time, the height and direction of monitoring can be adjusted according to different usage environments, thereby improving the convenience of use.

[0005] Although the above-mentioned equipment can adjust the monitoring height and direction according to different usage environments to achieve effective monitoring of dust, in actual deployment and application, dust detectors generally use dust detection devices as their core components. During the operation of the dust detection device, it usually relies on power devices such as air pumps or fans to continuously pull air samples through the inside of the monitoring equipment. However, in long-term monitoring activities, a certain amount of dust will inevitably be adsorbed inside the monitoring equipment. Over time, the gradual accumulation of dust will significantly affect the accuracy of the monitoring data, especially when dust adheres to the sensitive mirror of the sensor or light receiver, which poses a more serious threat to the accuracy of subsequent monitoring results. In view of this, it is particularly important to clean and maintain the monitoring equipment regularly.

[0006] However, this process not only involves complex disassembly operations, increasing the difficulty and tediousness of the operation, but also in actual operation, it is extremely difficult to accurately judge the cleaning time. If the cleaning work is carried out too early, it may lead to unnecessary waste of human resources; on the contrary, if the cleaning work is delayed, the accuracy of the monitoring results may be severely damaged due to excessive dust accumulation.

[0007] In view of this, it is particularly crucial and urgent to develop an air pollutant concentration detection device that can effectively overcome the above technical problems. Summary of the Invention

[0008] The purpose of the present invention is to provide an air pollutant concentration detection device to solve the technical problems raised in the above background technology.

[0009] To achieve the above purpose, the present invention provides the following technical solutions: An air pollutant concentration detection device, comprising: A housing, the housing includes an upper housing and a lower housing; A circuit board, the circuit board is arranged between the upper housing and the lower housing, a processing circuit is arranged on the upper surface of the circuit board, and a laser detection component is arranged on the lower surface of the circuit board; A "mountain"-shaped channel, a "mountain"-shaped channel is arranged inside the lower housing, the "mountain"-shaped channel includes a "凵"-shaped part and a "丨"-shaped part, air flow flows in the "凵"-shaped part, and the laser detection component detects the air flow flowing through the "凵"-shaped part; Pressure-receiving parts, pressure-receiving parts are arranged at the corners of the "凵"-shaped part, and the pressure-receiving parts detect the air flow pressure flowing through the "凵"-shaped part; A piezoelectric air supply component, a piezoelectric air supply component is arranged outside the "凵"-shaped part; A cross-section regulation component, a cross-section regulation component is arranged inside the "凵"-shaped part, when the piezoelectric air supply component provides power to the cross-section regulation component, the cross-section regulation component generates deformations in different directions to adjust the cross-sectional area of the "mountain"-shaped channel.

[0010] Preferably, the laser detection component includes: A laser generator, the laser generator is arranged on the lower surface of the circuit board, and after the circuit board and the lower housing are assembled, the laser generator is adapted to the "丨"-shaped part; A light receiver, the light receiver is arranged outside the laser generator, and after the circuit board and the lower housing are assembled, the light receiver is located at the junction of the "丨"-shaped part and the "凵"-shaped part.

[0011] Preferably, the cross-section regulation component includes: A sealing plate, which is arranged inside the lower housing and fixedly connected to the top of the "mountain"-shaped channel; a relief groove corresponding to the "U"-shaped part is provided on the sealing plate. A sealing cavity, which includes a first chamber and a second chamber. The first chamber and the second chamber are distributed on both sides of the "vertical bar"-shaped part. The first chamber and the second chamber are formed by the lower housing, the sealing plate, and the "mountain"-shaped channel.

[0012] Preferably, the cross-section regulating assembly further includes: An installation groove, which is opened on the inner wall of the "U"-shaped part; An elastic membrane, which is arranged inside the installation groove. By introducing gas into the sealing cavity, the elastic membrane is forced to expand to change the cross-sectional area of the "U"-shaped part.

[0013] Preferably, a first connecting pipe and a second connecting pipe are provided between the first chamber and the second chamber, and the first connecting pipe and the second connecting pipe do not contact each other.

[0014] Preferably, the piezoelectric air supply assembly includes: A piezoelectric pump body, which is arranged inside the housing; Piezoelectric sheets, which are arranged inside the piezoelectric pump body. The upper cavity and the lower cavity inside the piezoelectric pump body are both provided with piezoelectric sheets. By applying a voltage to the piezoelectric sheets, the piezoelectric sheets are forced to deform to realize the pumping and discharging operation of the piezoelectric pump body.

[0015] Preferably, the piezoelectric air supply assembly further includes: A first suction pipe and a first exhaust pipe, which are arranged on the top of the piezoelectric pump body. The first suction pipe and the first exhaust pipe are both connected to the upper cavity. The first exhaust pipe is connected to the first connecting pipe, and the first suction pipe is connected to the outside of the lower housing; A second suction pipe and a second exhaust pipe, which are arranged on the bottom of the piezoelectric pump body. The second suction pipe and the second exhaust pipe are both connected to the lower cavity. The second suction pipe is connected to the second connecting pipe, and the second exhaust pipe is connected to the outside of the lower housing.

[0016] Preferably, the lower housing is provided with an air inlet and an air outlet. The air inlet is arranged at the air inlet end of the "U"-shaped part; the air outlet is arranged at the air outlet end of the "U"-shaped part. A suction fan connected to the lower housing is provided at the air outlet end of the "U"-shaped part, and the suction fan is connected to the outside of the lower housing.

[0017] Preferably, a blocking assembly is arranged on the lower housing, and the blocking assembly is distributed at the air inlet and the air outlet of the "U"-shaped part. The blocking assembly is used to block the air inlet and the air outlet of the "U"-shaped part.

[0018] Preferably, the blocking component includes: A fixing part fixedly connected to the outside of the lower housing; A movable part disposed inside the fixing part. When the movable part is in the extended state, the movable part blocks the air inlet and the air outlet of the "U"-shaped part. When the movable part is in the contracted state, the movable part releases the blocking of the air inlet and the air outlet of the "U"-shaped part.

[0019] The technical effects and advantages of the present invention: 1. By providing the piezoelectric air supply component and the blocking component in the present invention, when dust accumulates inside the "U"-shaped part, the control system can monitor in real time and automatically start the piezoelectric air supply component for cleaning. This avoids the interference of dust accumulation on the laser detection component and ensures the continuous and stable operation of the device. Through the intermittent air flow impact and the alternating deformation of the piezoelectric sheet, precise cleaning of the blocked area is achieved. At the same time, the vibration generated by the piezoelectric air supply component helps to loosen the dust on the optical receiver, realizing comprehensive cleaning of the horizontal area of the "U"-shaped part, and improving the cleanliness and detection accuracy of the device.

[0020] 2. By providing the piezoelectric air supply component and the blocking component in the present invention, when the suction fan is blocked, by pausing the operation of the suction fan, blocking the air inlet and the air outlet of the "U"-shaped part, adjusting the working state of the piezoelectric sheet, and controlling the contraction of the elastic membrane, cleaning of the blocked area of the suction fan is achieved. This design not only avoids the decrease in suction capacity caused by the blockage of the suction fan but also ensures the smooth flow of air in the "U"-shaped part, thereby ensuring that the laser detection device can accurately judge the amount of dust in the air.

[0021] 3. By providing the piezoelectric air supply component and the blocking component in the present invention, when the air inlet of the "U"-shaped part is blocked, by pausing the operation of the suction fan, blocking the air inlet and the air outlet of the "U"-shaped part, adjusting the working state of the piezoelectric sheet, and controlling the expansion of the elastic membrane, cleaning of the blocked area of the air inlet is achieved. This avoids the problem of poor air flow caused by the blockage of the air inlet and ensures that the laser detection device can continuously and stably make an accurate judgment on the amount of dust in the air. Description of the Drawings

[0022] Figure 1 is a schematic diagram of the main structure of the present invention; Figure 2 is a schematic diagram of the structure of another perspective of the main structure of the present invention; Figure 3 is an exploded schematic diagram of the main structure of the present invention; Figure 4 is a schematic diagram of the structure of the circuit board of the present invention; Figure 5Schematic structural diagram of the lower housing of the present invention; Figure 6 Schematic structural diagram of the sealing cavity of the present invention; Figure 7 Schematic cross-sectional structural diagram of the lower housing of the present invention; Figure 8 Schematic diagram of the first working state of the piezoelectric air supply assembly of the present invention; Fig. 9 Schematic diagram of the second working state of the piezoelectric air supply assembly of the present invention.

[0023] Reference numerals are: 1. Outer shell; 101. Upper housing; 102. Lower housing; 2. Circuit board; 3. Laser detection assembly; 301. Laser generator; 302. Optical receiver; 4. "Mountain"-shaped channel; 401. "凵"-shaped part; 402. "丨"-shaped part; 5. Piezoelectric air supply assembly; 501. Piezoelectric pump body; 502. Upper cavity; 503. Lower cavity; 504. Piezoelectric sheet; 505. First suction pipe; 506. First exhaust pipe; 507. Second suction pipe; 508. Second exhaust pipe; 6. Cross-section adjustment assembly; 601. Sealing plate; 602. Sealing cavity; 6021. First chamber; 6022. Second chamber; 603. Installation groove; 604. Elastic membrane; 7. Suction fan; 8. Blocking assembly; 801. Fixed part; 802. Movable part; 9. Compressed part; 10. First connecting pipe; 11. Second connecting pipe. Specific embodiments

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0025] Embodiment 1 The present invention provides an air pollutant concentration detection device, including an outer shell 1, and the outer shell 1 includes an upper housing 101 and a lower housing 102.

[0026] A circuit board 2 is provided between the upper housing 101 and the lower housing 102. A processing circuit is provided on the upper surface of the circuit board 2, and a laser detection assembly 3 is provided on the lower surface of the circuit board 2.

[0027] Bolt assemblies are provided at the four corners of the housing 1, and the bolt assemblies connect the upper housing 101, the circuit board 2, and the lower housing 102 together.

[0028] The "mountain"-shaped channel 4 is provided inside the lower housing 102. The "mountain"-shaped channel 4 includes a "U"-shaped part 401 and a "vertical" part 402. The air flow flows in the "U"-shaped part 401, and the laser detection assembly 3 detects the air flow flowing through the "U"-shaped part 401.

[0029] Refer to Figure 3 to Figure 4 As shown, the laser detection assembly 3 includes a laser generator 301. The laser generator 301 is arranged on the lower surface of the circuit board 2. After the circuit board 2 and the lower housing 102 are fitted together, the laser generator 301 is adapted to the "vertical" part 402.

[0030] After the laser generator 301 enters the "vertical" part 402, it blocks the "vertical" part 402, that is, the air flow flowing through the "U"-shaped part 401 cannot enter the "vertical" part 402.

[0031] The laser detection assembly 3 further includes a light receiver 302. The light receiver 302 is arranged outside the laser generator 301. After the circuit board 2 and the lower housing 102 are fitted together, the light receiver 302 is located at the junction of the "vertical" part 402 and the "U"-shaped part 401.

[0032] Refer to Figures 1 to 6 As shown, the lower housing 102 is provided with an air inlet and an air outlet. The air inlet is arranged at the air inlet end of the "U"-shaped part 401; the air outlet is arranged at the air outlet end of the "U"-shaped part 401. A suction fan 7 connected to the lower housing 102 is provided at the air outlet end of the "U"-shaped part 401, and the suction fan 7 is communicated with the outside of the lower housing 102.

[0033] During use, the suction fan 7 is started, and the suction fan 7 sucks the external air. The external air enters the "U"-shaped part 401 through the air inlet of the lower housing 102, and the air flow flows along the "U"-shaped part 401. When the air flow flows through the horizontal part of the "U"-shaped part 401, the laser detection assembly 3 detects the dust content in the air flow. As the air flow continues to flow, it finally discharges from the suction fan 7 out of the housing. Since the suction fan 7 and the air inlet of the lower housing 102 are in two different directions, a stable air flow path can be formed during the continuous operation of the suction fan 7, effectively avoiding the occurrence of air flow short circuit and eddy current phenomena. This design not only enhances the residence time and dispersion uniformity of dust particles in the "U"-shaped part 401, but also significantly improves the measurement accuracy and reliability of the laser detection assembly 3 for the dust content.

[0034] Principle of the laser detection component 3 for detecting dust: The laser generator 301 emits a laser beam. When the air flow passes through the position where the laser beam is located, the beam is scattered due to the influence of dust in the air flow. When the scattered light irradiates the light receiver 302, the light receiver 302 generates an electrical signal proportional to the intensity of the scattered light. The generated electrical signal is amplified and filtered and then sent to the signal processing unit on the circuit board 2. The signal processing unit further processes and analyzes the electrical signal to calculate the dust concentration.

[0035] Embodiment 2 Although the above embodiment can detect the dust concentration in the air flow using the laser detection component 3 to a certain extent, in the actual application process, since the suction fan 7 is in a continuous working state, over time, a large amount of dust inevitably adheres to the air duct. Especially when the dust adheres to the surface of the light receiver 302, it poses a more serious threat to the accuracy of subsequent monitoring results. In view of this, based on Embodiment 1, technical improvements are made, and the improved technical solution is as follows: Refer to Figure 6 to Figure 7 As shown, pressure-receiving members 9 are provided at the corners of the "凵"-shaped part 401, and the pressure-receiving members 9 detect the air flow pressure passing through the "凵"-shaped part 401.

[0036] In this embodiment, two pressure-receiving members 9 are provided. The two pressure-receiving members 9 are respectively located at both ends of the horizontal part of the "凵"-shaped part 401. The structure of each pressure-receiving member 9 includes a flexible membrane fixedly connected to the "凵"-shaped part 401 and an elastic member provided inside the flexible membrane. One end of the elastic member is connected to the flexible membrane, and the other end is fixedly connected to the "凵"-shaped part 401. An inductive sensor is particularly provided at the connection between the elastic member and the "凵"-shaped part 401 to detect the telescopic state of the elastic member.

[0037] The working principle of the inductive sensor here is based on the fact that when the elastic member is used as a sensing element, its inductance changes directly with the change in length. Therefore, by measuring the inductance of the elastic member, its current telescopic state can be effectively judged.

[0038] When the air flow passes through the "凵"-shaped part 401, it generates pressure on the pressure-receiving member 9, causing the elastic member to be compressed. By detecting the compression amount of the elastic member, that is, the change in its inductance, the air flow pressure value can be judged. Since two pressure-receiving members 9 are provided in this embodiment, respectively located at both ends of the "凵"-shaped part 401, the dust adhesion situation between different positions inside the "凵"-shaped part 401 can be judged by comparing the states of these two pressure-receiving members 9, that is, the compression amounts they receive and the corresponding inductance changes.

[0039] Refer to Figures 6 to 9As shown, a piezoelectric air supply assembly 5 is provided on the outer side of the "凵"-shaped part 401.

[0040] Referring to Figure 6 As shown, a cross-section control assembly 6 is provided inside the "凵"-shaped part 401. When the piezoelectric air supply assembly 5 provides power to the cross-section control assembly 6, the cross-section control assembly 6 generates deformations in different directions to adjust the cross-sectional area of the "mountain"-shaped channel 4.

[0041] Referring to Figures 3 to 6 As shown, the cross-section control assembly 6 includes a sealing plate 601. The sealing plate 601 is arranged inside the lower housing 102 and is fixedly connected to the top of the "mountain"-shaped channel 4. A relief groove corresponding to the "凵"-shaped part 401 is provided on the sealing plate 601. The relief groove is used to allow the laser generator 301 to enter the "丨"-shaped part 402.

[0042] The height of the laser generator 301 is equal to the height of the "mountain"-shaped channel 4 plus the thickness of the sealing plate 601.

[0043] The cross-section control assembly 6 further includes a sealing cavity 602. The sealing cavity 602 includes a first chamber 6021 and a second chamber 6022. The first chamber 6021 and the second chamber 6022 are distributed on both sides of the "丨"-shaped part 402. The first chamber 6021 and the second chamber 6022 are formed by the lower housing 102, the sealing plate 601, and the "mountain"-shaped channel 4.

[0044] The cross-section control assembly 6 further includes a mounting groove 603. The mounting groove 603 is opened on the inner wall of the "凵"-shaped part 401. An elastic membrane 604 is provided inside the mounting groove 603. By introducing gas into the sealing cavity 602, the elastic membrane 604 is forced to expand to change the cross-sectional area of the "凵"-shaped part 401.

[0045] Referring to Figures 2 to 7 As shown, a first communication pipe 10 and a second communication pipe 11 are provided between the first chamber 6021 and the second chamber 6022, and the first communication pipe 10 and the second communication pipe 11 do not contact each other.

[0046] Referring to Figures 8 to 9 As shown, the piezoelectric air supply assembly 5 includes a piezoelectric pump body 501. The piezoelectric pump body 501 is arranged inside the housing. An upper cavity 502 and a lower cavity 503 are provided inside the piezoelectric pump body 501. Piezoelectric sheets 504 are provided inside both the upper cavity 502 and the lower cavity 503. By applying a voltage to the piezoelectric sheets 504, the piezoelectric sheets 504 are forced to deform to achieve the pumping and discharging operations of the piezoelectric pump body 501.

[0047] By using the inverse piezoelectric effect, when an electric field is applied to both ends of the piezoelectric sheet 504, the piezoelectric sheet 504 will deform or vibrate. When the direction of the applied electric field is the same as the polarization direction of the piezoelectric sheet 504, the polarization strength of the piezoelectric sheet 504 will increase, causing the piezoelectric sheet 504 to stretch and deform in the polarization direction; and when the direction of the applied electric field is opposite to the polarization direction, the polarization strength of the piezoelectric sheet 504 will weaken, causing the piezoelectric sheet 504 to shorten in the polarization direction. Therefore, when an alternating electric field is applied to both ends of the piezoelectric sheet 504, the piezoelectric sheet 504 will produce an alternating deformation with the same frequency as the alternating electric field.

[0048] The alternating deformation of the piezoelectric sheet 504 generates suction force inside the upper cavity 502 and the lower cavity 503, thereby achieving expansion and contraction of the first cavity 6021 and the second cavity 6022. Using the alternating deformation of the piezoelectric sheet 504 to achieve fluid suction is a prior art and will not be described in detail here.

[0049] The piezoelectric air supply assembly 5 also includes a first air suction pipe 505 and a first exhaust pipe 506. The first air suction pipe 505 and the first exhaust pipe 506 are arranged at the top of the piezoelectric pump body 501. The first air suction pipe 505 and the first exhaust pipe 506 are both connected to the upper cavity 502. The first exhaust pipe 506 is connected to the first connecting pipe 10. The first air suction pipe 505 is connected to the outside of the lower shell 102.

[0050] The piezoelectric air supply assembly 5 also includes a second air suction pipe 507 and a second exhaust pipe 508, which are arranged at the bottom of the piezoelectric pump body 501, and the second air suction pipe 507 and the second exhaust pipe 508 are both connected to the lower cavity 503, the second air suction pipe 507 is connected to the second connecting pipe 11, and the second exhaust pipe 508 is connected to the outside of the lower shell 102.

[0051] The first connecting pipe 10 is provided with a first installation valve and a second installation valve at both ends. When the first installation valve is in the started state and the second installation valve is in the closed state, the first connecting pipe 10 is in a connected state with the first chamber 6021; when the first installation valve is in the closed state and the second installation valve is in the started state, the first connecting pipe 10 is in a connected state with the second chamber 6022; when the first installation valve and the second installation valve are both in the started state, the first connecting pipe 10 is in a connected state with both the first chamber 6021 and the second chamber 6022.

[0052] The two ends of the second connecting pipe 11 are provided with a first connection valve and a second connection valve. When the first connection valve is in the open state and the second connection valve is in the closed state, the second connecting pipe 11 is in communication with the first chamber 6021; when the first connection valve is in the closed state and the second connection valve is in the open state, the second connecting pipe 11 is in communication with the second chamber 6022; when both the first connection valve and the second connection valve are in the open state, the second connecting pipe 11 is in communication with both the first chamber 6021 and the second chamber 6022.

[0053] Refer to Figures 1 to 7 As shown, a blocking assembly 8 is provided on the lower housing 102. The blocking assembly 8 is distributed at the air inlet and air outlet of the "U"-shaped portion 401, and the blocking assembly 8 is used to block the air inlet and air outlet of the "U"-shaped portion 401.

[0054] Refer to Figures 1 to 7 As shown, the blocking assembly 8 includes a fixing portion 801, and the fixing portion 801 is fixedly connected to the outside of the lower housing 102.

[0055] The blocking assembly 8 further includes a movable portion 802. The movable portion 802 is arranged inside the fixing portion 801. When the movable portion 802 is in the extended state, the movable portion 802 blocks the air inlet and air outlet of the "U"-shaped portion 401. When the movable portion 802 is in the contracted state, the movable portion 802 releases the blocking of the air inlet and air outlet of the "U"-shaped portion 401.

[0056] The movable portion 802 includes a movable plate. The movable plate is used to block the air inlet and air outlet of the lower housing 102. The movable plate is slidably connected to the fixing portion 801, and a driving component is arranged inside the fixing portion 801. The driving component is used to drive the telescopic movement of the movable plate.

[0057] A control chip connected to the processing circuit is provided on the upper surface of the circuit board 2. A control system is provided inside the control chip, and the control system is used to control the movement of all the electrical components on the housing 1.

[0058] In this embodiment, the two pressure-receiving members 9 provided on the "U"-shaped portion 401 are an A pressure-receiving portion and a B pressure-receiving portion respectively. By detecting the states of the A pressure-receiving portion and the B pressure-receiving portion, the dust adhesion situation between different positions inside the "U"-shaped portion 401 is judged.

[0059] Initially, when the movable portion 802 is in the contracted state, the movable portion 802 releases the blocking of the air inlet and air outlet of the lower housing 102; when both the first installation valve and the second installation valve are in the closed state, the first connecting pipe 10 is in a non-connected state with both the first chamber 6021 and the second chamber 6022; when both the first connection valve and the second connection valve are in the closed state, the second connecting pipe 11 is in a non-connected state with both the first chamber 6021 and the second chamber 6022.

[0060] During use, under normal circumstances, the states between the A pressure-receiving part and the B pressure-receiving part are both in a pressure-receiving state. That is, when the air flow flows in the "凵"-shaped part 401, there is no excessive dust in the "凵"-shaped part 401, so that the pressure generated by the air flow on the A pressure-receiving part and the B pressure-receiving part makes the two in a stable pressure-receiving state.

[0061] It should be noted that when the suction fan 7 is in a non-working state, the A pressure-receiving part and the B pressure-receiving part are not affected by the air flow pressure, and at this time, both the A pressure-receiving part and the B pressure-receiving part are in a stable state.

[0062] When the air flow passes through the inside of the "凵"-shaped part 401, if the pressure-receiving state of the A pressure-receiving part is further aggravated while the pressure-receiving state of the B pressure-receiving part gradually decreases, it indicates that there is a phenomenon of dust accumulation in the horizontal flat area of the "凵"-shaped part 401.

[0063] Specifically, when there is a phenomenon of dust accumulation in the horizontal flat area of the "凵"-shaped part 401, since the suction fan 7 is still running continuously, the fluid accumulates in the area before the blockage point and generates a higher pressure, resulting in a further aggravation of the pressure-receiving state of the A pressure-receiving part; because the fluid cannot pass through the blockage point smoothly, the pressure after the blockage point will decrease, which in turn causes the pressure-receiving state of the B pressure-receiving part to gradually decrease.

[0064] When the control system detects the phenomenon of dust accumulation in the horizontal flat area of the "凵"-shaped part 401, it controls the first connecting pipe 10 to be in a connected state with the first chamber 6021; at the same time, when an alternating electric field is applied to the piezoelectric sheet 504 inside the upper cavity 502, the piezoelectric sheet 504 generates alternating deformation. The working state of the piezoelectric sheet 504 inside the upper cavity 502 refers to Figure 8 As shown, during the process of the alternating deformation of the piezoelectric sheet 504, external gas is introduced into the first chamber 6021 through the first suction pipe 505 and the first exhaust pipe 506, so that the air pressure inside the first chamber 6021 increases, and the gas squeezes the elastic membrane 604, forcing the elastic membrane 604 to expand, thereby reducing the cross-sectional area of the air inlet of the "凵"-shaped part 401, increasing the speed of the gas flowing through the air inlet of the "凵"-shaped part 401, and enabling the air flow to impact and clean the blocked area to ensure the normal operation of the laser detection component 3.

[0065] During the working process of the piezoelectric air supply component 5, the movable part 802 located at the air inlet of the "凵"-shaped part 401 is controlled to perform reciprocating motion, that is, the movable part 802 intermittently blocks the air inlet of the "凵"-shaped part 401, so that the air flow enters the "凵"-shaped part 401 in an intermittent manner, improving the impact intensity of the air flow on the blocked area.

[0066] It should be noted that during the operation of the piezoelectric air supply component 5, certain vibrations will be generated by itself. The vibrations are conducted to the circuit board 2 through the lower housing 102, causing the dust adhered to the optical receiver 302 to become loose. Under the influence of vibrations and air flow impacts, a comprehensive cleaning of the horizontal area of the "凵"-shaped part 401 is achieved, avoiding the accumulation of dust in the "凵"-shaped part 401 and affecting the detection results of the laser detection component 3.

[0067] During the cleaning process by air flow impact, the state of the B pressure-receiving part is monitored synchronously. When the B pressure-receiving part returns to the pressure-receiving state under normal conditions, the first communication pipe 10 returns to its initial state, and the piezoelectric sheet 504 inside the upper cavity 502 stops working; at the same time, the second communication pipe 11 is controlled to be in communication with the first chamber 6021, and the piezoelectric sheet 504 inside the lower cavity 503 is controlled to work. The piezoelectric sheet 504 extracts and discharges the gas inside the first chamber 6021 through the second extraction pipe 507 and the second exhaust pipe 508, so that the "凵"-shaped part 401 returns to its original cross-sectional area.

[0068] When the control system monitors that the A pressure-receiving part and the B pressure-receiving part gradually return to the normal state or their pressure-receiving states are reduced during the process of air flow flowing through the inside of the "凵"-shaped part 401, it indicates that there is a blockage between the blades of the suction fan 7.

[0069] Specifically: after there is a blockage between the blades of the suction fan 7, the suction force generated by the suction fan 7 gradually decreases, which in turn leads to a reduction in the flow rate entering the "凵"-shaped part 401, thereby causing the pressure of the air flow on the A pressure-receiving part and the B pressure-receiving part to decrease, resulting in the A pressure-receiving part and the B pressure-receiving part gradually returning to the normal state or their pressure-receiving states gradually decreasing.

[0070] When a blockage occurs in the area of the suction fan 7, first control the suction fan 7 to pause operation, and at the same time control the two blocking components 8 provided on the housing 1 to block the air inlet and outlet of the "凵"-shaped part 401, so that the "凵"-shaped part 401 forms a sealed chamber; then control the second communication pipe 11 to be in communication with both the first chamber 6021 and the second chamber 6022, and control the piezoelectric sheet 504 inside the lower cavity 503 to perform alternating deformation. The working state of the piezoelectric sheet 504 inside the lower cavity 503 refers to Fig. 9As shown, during the process of the piezoelectric sheet 504 undergoing alternating deformation, the gas inside the first chamber 6021 and the second chamber 6022 is extracted through the second air extraction pipe 507 and the second exhaust pipe 508, forcing the corresponding elastic membranes 604 of the first chamber 6021 and the second chamber 6022 to contract, causing the cross-sectional area of the air inlet of the "凵"-shaped part 401 to expand, generating a negative pressure inside the "凵"-shaped part 401. When the elastic membrane 604 contracts to a set amount, the blocking part at the air outlet of the "凵"-shaped part 401 releases the blockage of the suction fan 7. At this time, affected by the negative pressure, the external air flow enters the "凵"-shaped part 401 from the suction fan 7, and the external air flow impacts the suction fan 7, causing the dust adhering between its blades to fall. This avoids the reduction of the suction capacity after the suction fan 7 is blocked, which may lead to the failure of the air flow to flow smoothly inside the "凵"-shaped part 401, resulting in the laser detection device being unable to accurately judge the dust amount in the air.

[0071] When the air flow passes through the inside of the "凵"-shaped part 401, when the control system monitors that the A pressure-receiving part and the B pressure-receiving part gradually return to the normal state and gradually show a stretching phenomenon, it indicates that the air inlet of the "凵"-shaped part 401 is blocked.

[0072] Specifically: After the air inlet of the "凵"-shaped part 401 is blocked, the flow rate entering the "凵"-shaped part 401 decreases. However, affected by the suction force of the suction fan 7, a negative pressure gradually generates inside the "凵"-shaped part 401. Affected by the negative pressure, the A pressure-receiving part and the B pressure-receiving part gradually show a stretching phenomenon.

[0073] When the air inlet of the "凵"-shaped part 401 is blocked, first control the suction fan 7 to pause operation, and at the same time control the two blocking components 8 provided on the housing 1 to block the air inlet and the air outlet of the "凵"-shaped part 401, making the "凵"-shaped part 401 form a closed chamber; then control the first connecting pipe 10 to be in a connected state with both the first chamber 6021 and the second chamber 6022, and control the piezoelectric sheet 504 inside the upper cavity 502 to undergo alternating deformation. The working state of the piezoelectric sheet 504 inside the upper cavity 502 refers to Figure 8As shown, during the process of the piezoelectric sheet 504 undergoing alternating deformation, the first chamber 6021 and the second chamber 6022 are inflated through the first air extraction pipe 505 and the first exhaust pipe 506, forcing the elastic membranes 604 corresponding to the first chamber 6021 and the second chamber 6022 to expand, so that the cross-sectional area of the air inlet of the "凵"-shaped part 401 is reduced, and a positive pressure is generated inside the "凵"-shaped part 401. When the elastic membrane 604 expands to a set amount, the blocking part at the air inlet of the "凵"-shaped part 401 releases the blockage of the air inlet of the "凵"-shaped part 401. At this time, the gas inside the "凵"-shaped part 401 is affected by the positive pressure and sprays out from the air inlet of the "凵"-shaped part 401, causing the dust adhering to the air inlet of the "凵"-shaped part 401 to fall, avoiding the situation that after the air inlet of the "凵"-shaped part 401 is blocked, the air flow cannot enter the air inlet of the "凵"-shaped part 401, resulting in the laser detection device being unable to accurately judge the dust amount in the air.

[0074] As mentioned above, the above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.

Claims

1. An air pollutant concentration detection device, characterized in that: Comprising: A housing (1), the housing (1) includes an upper housing (101) and a lower housing (102); A circuit board (2), the circuit board (2) is disposed between the upper housing (101) and the lower housing (102), a processing circuit is provided on the upper surface of the circuit board (2), and a laser detection component (3) is provided on the lower surface of the circuit board (2); A "mountain"-shaped channel (4), the "mountain"-shaped channel (4) is provided inside the lower housing (102), the "mountain"-shaped channel (4) includes a "U"-shaped portion (401) and a "vertical" portion (402), air flows in the "U"-shaped portion (401), and the laser detection component (3) detects the air flow flowing through the "U"-shaped portion (401); Pressure-receiving members (9), pressure-receiving members (9) are provided at the corners of the "U"-shaped portion (401), and the pressure-receiving members (9) detect the air flow pressure flowing through the "U"-shaped portion (401); A piezoelectric air supply component (5), the piezoelectric air supply component (5) is provided outside the "U"-shaped portion (401); A cross-section adjustment component (6), the cross-section adjustment component (6) is provided inside the "U"-shaped portion (401), when the piezoelectric air supply component (5) provides power to the cross-section adjustment component (6), the cross-section adjustment component (6) generates deformations in different directions to adjust the cross-sectional area of the "mountain"-shaped channel (4).

2. The air pollutant concentration detection device according to claim 1, characterized in that: The laser detection component (3) includes: A laser generator (301), the laser generator (301) is provided on the lower surface of the circuit board (2), after the circuit board (2) and the lower housing (102) are assembled, the laser generator (301) is adapted to the "vertical" portion (402); A light receiver (302), the light receiver (302) is provided outside the laser generator (301), after the circuit board (2) and the lower housing (102) are assembled, the light receiver (302) is located at the junction of the "vertical" portion (402) and the "U"-shaped portion (401).

3. The air pollutant concentration detection device according to claim 1, characterized in that: The cross-section adjustment component (6) includes: A sealing plate (601), the sealing plate (601) is provided inside the lower housing (102) and is fixedly connected to the top of the "mountain"-shaped channel (4); a relief groove corresponding to the "U"-shaped portion (401) is provided on the sealing plate (601); A sealing cavity (602), the sealing cavity (602) includes a first chamber (6021) and a second chamber (6022), the first chamber (6021) and the second chamber (6022) are distributed on both sides of the "vertical" portion (402), and the first chamber (6021) and the second chamber (6022) are formed by the lower housing (102), the sealing plate (601) and the "mountain"-shaped channel (4).

4. The air pollutant concentration detection device according to claim 3, characterized in that: The cross-section adjustment component (6) further includes: An installation groove (603), the installation groove (603) is opened on the inner wall of the "U"-shaped portion (401); An elastic membrane (604), the elastic membrane (604) is provided inside the installation groove (603), by introducing gas into the sealing cavity (602), the elastic membrane (604) is forced to expand to change the cross-sectional area of the "U"-shaped portion (401).

5. The air pollutant concentration detection device according to claim 3, characterized in that: A first connecting pipe (10) and a second connecting pipe (11) are provided between the first chamber (6021) and the second chamber (6022), and the first connecting pipe (10) and the second connecting pipe (11) do not contact each other.

6. The air pollutant concentration detection device according to claim 5, characterized in that: The piezoelectric air supply assembly (5) includes: A piezoelectric pump body (501) disposed inside the housing; Piezoelectric sheets (504). An upper cavity (502) and a lower cavity (503) are provided inside the piezoelectric pump body (501), and piezoelectric sheets (504) are provided inside both the upper cavity (502) and the lower cavity (503). By applying a voltage to the piezoelectric sheets (504), the piezoelectric sheets (504) are forced to deform, thereby realizing the pumping and discharging operations of the piezoelectric pump body (501).

7. The air pollutant concentration detection device according to claim 6, characterized in that: The piezoelectric air supply assembly (5) further includes: A first suction pipe (505) and a first exhaust pipe (506). The first suction pipe (505) and the first exhaust pipe (506) are disposed at the top of the piezoelectric pump body (501). The first suction pipe (505) and the first exhaust pipe (506) are both connected to the upper cavity (502). The first exhaust pipe (506) is connected to the first connecting pipe (10), and the first suction pipe (505) is connected to the outside of the lower housing (102). A second suction pipe (507) and a second exhaust pipe (508). The second suction pipe (507) and the second exhaust pipe (508) are disposed at the bottom of the piezoelectric pump body (501). The second suction pipe (507) and the second exhaust pipe (508) are both connected to the lower cavity (503). The second suction pipe (507) is connected to the second connecting pipe (11), and the second exhaust pipe (508) is connected to the outside of the lower housing (102).

8. The air pollutant concentration detection device according to claim 1, characterized in that: The lower housing (102) is provided with an air inlet and an air outlet. The air inlet is disposed at the air inlet end of the "凵”-shaped part (401); the air outlet is disposed at the air outlet end of the "凵”-shaped part (401). A suction fan (7) connected to the lower housing (102) is provided at the air outlet end of the "凵”-shaped part (401), and the suction fan (7) is connected to the outside of the lower housing (102).

9. The air pollutant concentration detection device according to claim 8, characterized in that: A blocking assembly (8) is provided on the lower housing (102). The blocking assembly (8) is distributed at the air inlet and the air outlet of the "凵”-shaped part (401), and the blocking assembly (8) is used to block the air inlet and the air outlet of the "凵”-shaped part (401).

10. The air pollutant concentration detection device according to claim 9, characterized in that: The blocking assembly (8) includes: A fixing part (801) fixedly connected to the outside of the lower housing (102); A movable part (802). The movable part (802) is disposed inside the fixing part (801). When the movable part (802) is in the extended state, the movable part (802) blocks the air inlet and the air outlet of the "凵”-shaped part (401). When the movable part (802) is in the contracted state, the movable part (802) releases the blocking of the air inlet and the air outlet of the "凵”-shaped part (401).

Images