An aerosol sensor detection system and detection device

Abstract

The present application relates to a kind of aerosol sensor detection system and detection device, detection system includes power supply conversion unit, controller unit, aerosol detection unit, data interface unit and abnormal state monitoring unit.Detection device includes main shell, PCB support, PCB board and bottom shell.The detection system of the present application can ensure that the light source intensity emitted by infrared LED light emitting tube is consistent each time by using closed-loop control of hardware and software, effectively improve the accuracy of detection system.The detection device of the present application increases lens in front of photoelectric tube, gathers the scattered light source, thereby preliminarily improves the signal level of photoelectric tube, and can improve the resolution of sensor to some extent.

Description

Technical Field

[0001] This invention relates to the field of aerosol sensor detection technology, specifically to an aerosol sensor detection system and detection device. Background Technology

[0002] Aerosols are gaseous dispersion systems composed of solid or liquid particles suspended in a gaseous medium. Because they scatter light, aerosol detection systems typically consist of LEDs and photocells. The LED emits a specific light source, which, after being scattered by the aerosol, is received by the photocell. The concentration of aerosols in the environment is determined by the intensity of the light received by the photocell. However, the light source attenuates after scattering by the aerosol, reducing the resolution and accuracy of the photocell, thus lowering the detection accuracy of existing aerosol sensors. Furthermore, the open-loop control of the LED, under continuous operation, generates heat accumulation due to constant light emission, affecting the stability of the photocell. Secondly, circuit or environmental factors can cause fluctuations in the LED's driving voltage, leading to inconsistent light intensity and ultimately affecting the accuracy of the aerosol sensor. Summary of the Invention

[0003] The technical problem solved by this invention is to provide an aerosol sensor detection system and device with high detection accuracy based on LED closed-loop control.

[0004] The technical solution adopted by this invention to solve its technical problem is:

[0005] An aerosol sensor detection system includes a power conversion unit, a controller unit, an aerosol detection unit, a data interface unit, and an abnormal state monitoring unit. The power conversion unit provides the detection system with the required stable driving voltage. The aerosol detection unit collects analog signals of aerosol concentration in the environment. The controller unit is a system controller used to convert the analog aerosol concentration signals into digital signals and perform data processing. The data interface unit is used for interaction and data transmission with a host system. The abnormal state monitoring unit monitors the operating status of the system. The aerosol detection unit includes a light source emitting module and a light source receiving module. The light source emitting module includes a light-emitting diode (LED), and the light source receiving module includes a phototube. The LED and the phototube are arranged at a V-shaped angle, and a lens is placed in front of the phototube. The LED achieves closed-loop control through hardware filtering and software filtering.

[0006] The closed-loop control process of the LED through hardware filtering is as follows: Infrared LED D3 is driven by a PWM signal input through the LED_PWM port. The proportion of the PWM signal is adjusted. After the PWM signal is filtered by an RC filter composed of resistor R15 and capacitor C34, it controls the conduction of MOSFET Q7, thereby controlling the conduction of infrared LED D3 to emit infrared light. The PWM signal is input to the gate of MOSFET Q7 as its switch. The source of MOSFET Q7 is connected to a sampling resistor R20 and operational amplifier U5, and the drain of MOSFET Q7 is connected to infrared LED D3. Operational amplifier U5 and its peripheral circuits are used for impedance matching, forming a current sampling circuit. The source of MOSFET Q7 is connected to the non-inverting input of operational amplifier U5, and the output of operational amplifier U5 outputs the sampled current LED_Current. The MCU's AD module samples the current at LED_Current and outputs a voltage V. LC The current I at the infrared LED D3 led =I R20 =V LC / R20, based on the calculated current I led The current is compared with the target current, and the PWM duty cycle is controlled by the PID algorithm to adjust the current on the infrared LED D3 in real time to ensure its current stability. This achieves closed-loop control of the infrared LED to ensure the stability of its operating voltage and thus the stability of the output light source.

[0007] The process of achieving closed-loop control of the LED through software filtering is as follows: The LED_PWM drive signal calculates the working power of the LED based on AD sampling, and controls the LED_PWM drive signal through a PID algorithm to ensure the stability of the LED_PWM drive signal.

[0008] Furthermore, the power conversion unit includes an EMC / EMI circuit module, a reverse connection protection circuit module, and a voltage regulator circuit module.

[0009] Furthermore, the infrared LED driving module is also equipped with a current detection circuit module for adjusting the current of the infrared LED light-emitting tube.

[0010] Furthermore, the light source receiving module is also equipped with a signal amplification circuit module for amplifying the aerosol concentration analog signal.

[0011] Furthermore, the data interface unit includes a CAN bus transceiver module.

[0012] Furthermore, the abnormal state monitoring unit includes a power supply detection circuit module and an ambient temperature detection module.

[0013] An aerosol sensor detection device includes a main housing, a PCB support, a PCB board, and a bottom housing. The aerosol sensor detection system described above is arranged on the PCB board. The PCB board is fixed on the PCB support, and the PCB support and the PCB board are fixed inside the main housing. The bottom housing is assembled and fixed to the main housing to form the detection device.

[0014] Furthermore, the inner cavity of the main housing is provided with an upper emitting optical path, an upper receiving optical path, and a scattering chamber, and the upper end of the PCB bracket is provided with a lower emitting optical path, a lower receiving optical path, and a connector; the lower emitting optical path is inserted into the upper emitting optical path to form an emitting optical path, and the lower receiving optical path is inserted into the upper receiving optical path to form a receiving optical path.

[0015] Furthermore, the connector is integrally formed with the PCB bracket.

[0016] Furthermore, the upper and lower emitting optical paths, as well as the upper and lower receiving optical paths, are each provided with a plurality of U-shaped clamps. The U-shaped clamps of the upper and lower emitting optical paths are interlocked to form the emitting optical path, and the U-shaped clamps of the upper and lower receiving optical paths are interlocked to form the receiving optical path.

[0017] The beneficial effects of this invention are:

[0018] The detection system of the present invention can ensure that the light intensity emitted by the infrared LED is consistent each time by using closed-loop control of hardware and software, thus effectively improving the accuracy of the detection system.

[0019] The detection device of this invention improves the signal strength of the phototube by adding a lens in front of it, thereby focusing the scattered light source and enhancing the sensor's resolution to some extent. Furthermore, the main housing and the bottom housing are secured with snap-fits and latches, facilitating assembly and disassembly / repair.

[0020] The detection device of the present invention adopts a U-shaped clamping plate design for the emission and reception optical paths. The upper and lower U-shaped clamping plates are cross-clamped to form a circular or elliptical emission and reception optical path. This design can further facilitate the early assembly and later maintenance of the light-emitting tube, phototube and lens. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the detection system of the present invention;

[0022] Figure 2 This is a diagram of the main modules of the system of the present invention;

[0023] Figure 3 for Figure 2 Circuit schematic of the EMC / EMI module;

[0024] Figure 4 for Figure 2 Circuit schematic diagram of the CAN bus transceiver module;

[0025] Figure 5 for Figure 2 Other interface circuit schematics of the data interface unit;

[0026] Figure 6 for Figure 2 Circuit diagram of the light source emission module;

[0027] Figure 7 for Figure 2 Circuit schematic diagram of the light source receiving module;

[0028] Figure 8 for Figure 2 Circuit diagram of the abnormal state monitoring unit;

[0029] Figure 9 This is a structural diagram of the detection device of the present invention;

[0030] Figure 10 for Figure 9 Internal structure diagram of the main shell 1;

[0031] Figure 11 for Figure 9 Structural diagram of PCB bracket 2;

[0032] Figure 12 for Figure 9 Front cross-sectional view.

[0033] The diagram is marked as follows:

[0034] 1. Main housing; 2. PCB bracket; 3. PCB board; 4. Bottom housing;

[0035] 101. Bayonet; 102. Upper air inlet; 103. Upper transmitting optical path; 104. Upper receiving optical path; 105. Scattering chamber; 1031. Card plate; 201. Lower transmitting optical path; 202. Lower receiving optical path; 203. Connector; 401. Elastic buckle; 402. Lower air inlet pipe. Detailed Implementation

[0036] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0038] Specifically, this invention provides a detection system and detection device for an aerosol sensor.

[0039] like Figure 1 The diagram shown is a schematic of an aerosol sensor detection system, including a power conversion unit, a controller unit, an aerosol detection unit, a data interface unit, and an abnormal state monitoring unit. The power conversion unit provides the necessary stable voltage for the detection system. The controller unit consists of a core processor (MCU) and peripheral components. The aerosol detection unit collects analog signals of aerosol concentration in the environment. The data interface unit interacts with the host system (including but not limited to computer host systems, embedded systems such as vehicle infotainment systems, and other operating systems with some graphical interface). The abnormal state monitoring unit monitors the system's operating status to ensure normal system operation.

[0040] like Figure 2 The diagram shows the main modules of the aerosol sensor detection system. The power conversion unit includes an EMC / EMI circuit module and a voltage regulator module. The data interface unit includes a CAN bus transceiver circuit module based on the CAN bus protocol and a wake-up / request circuit module. The abnormal state monitoring unit includes a system voltage detection circuit module and an ambient temperature monitoring circuit module. The aerosol detection unit includes a light source emission module and a light source reception module.

[0041] The EMC / EMI circuit module in the aforementioned power conversion unit is used to suppress or eliminate various interference signals, ensuring the stability of the power conversion unit. The voltage regulator module includes a voltage regulator chip and peripheral components, outputting the stable drive voltage required by the detection system. The CAN bus transceiver circuit module in the data interface unit is used for interaction and data transmission, while the wake-up / request circuit module is used to control and switch the system's operating mode. The system voltage monitoring circuit module in the abnormal state monitoring unit samples the system operating voltage and calculates the power supply voltage value. The ambient temperature monitoring circuit module collects the operating ambient temperature, providing parameters to correct the aerosol concentration value, ensuring detection accuracy and system stability. The light source emission module in the aerosol detection unit outputs a stable light source, while the light source receiving module receives the light source scattered by the aerosol. In this invention, the light source emission module uses an infrared LED as the transmitter, and the light source receiving module uses an infrared phototube as the receiver.

[0042] To further realize the detection system of the present invention, the various modules of the present invention described above are illustrated below through specific embodiment circuit diagrams.

[0043] like Figure 3 The diagram shows the circuit diagram of the EMC / EMI module in the power conversion unit. TVS diode D7 is used to suppress pulse interference on the power line and also to suppress excessively high voltages. Inductor L2 is a common-mode inductor used to suppress common-mode interference on the power supply. Inductors L1 and L3, and ferrite beads FB1 and FB2 are used to filter out low-frequency and high-frequency differential-mode interference, respectively. MOSFET Q1, diode D1, resistor R2, and capacitor C1 form a reverse connection protection circuit module to protect the detection system. This reverse connection protection circuit module has a low on-state voltage drop characteristic.

[0044] like Figure 4 The diagram shows the circuit diagram of the CAN bus transceiver module in the data interface unit. Chip U2 is responsible for the conversion between CMOS level and CAN differential level. On the left, D2, capacitors C10 and C11, resistors R7 and R8, capacitor C13, and inductor L4 together form the EMC / EMI circuit module of the CAN interface, which is used to suppress and eliminate various interferences of the CAN bus transceiver module and ensure the stability of interactive communication.

[0045] like Figure 5The diagram shows the circuit diagram of the wake-up / request module in the data interface unit. The data interface unit has two ports for switching operating modes: the left circuit is the Request input circuit module, and the right circuit is the Wakeup output circuit module. The Request signal is controlled by the BMS battery management system. When the BMS system is in sleep mode, the Request signal is pulled low (0V), and the aerosol sensor detection system enters a low-power state with a sampling period of a first set threshold (e.g., 10s). When the BMS system is working, the Request signal is pulled high (12V), and the aerosol sensor detection system enters a continuous operating state with a sampling period of a second set threshold (e.g., 1s). The operating mode of the aerosol sensor detection system of this invention is controlled by the Request signal of the BMS system.

[0046] The aforementioned Wakeup signal is controlled by the aerosol sensor detection system. When the aerosol sensor is in continuous operation, Wakeup remains low (0V). When the sensor is in a low-power state, if the concentration of smoke or aerosol in the environment exceeds the set threshold, the sensor will raise Wakeup (12V) to wake up the BMS system and promptly alert it to potential safety hazards.

[0047] like Figure 6 The diagram shows the circuit diagram of the light source emission module in the aerosol detection unit. The infrared LED D3 is driven by a PWM signal input through the LED_PWM port. The PWM signal ratio is adjusted, and after passing through the RC filter composed of R15 and C34 on the left, the PWM signal controls the conduction of the MOSFET Q7, thereby controlling the conduction of the infrared LED D3 to emit infrared light. As shown in the diagram, the PWM signal is input to the gate of the MOSFET Q7 as its switch. A resistor R20 is connected to the source of the MOSFET Q7, and the drain is connected to the LED D3. The operational amplifier U5 and its surrounding circuitry form an impedance matching current sampling circuit. The MCU's AD module samples the output voltage (V) at LED_Current (LC). LC The current I at LED D3 led =I R20 =V LC / R20, based on the calculated current I led The current is compared with the target current, and the PWM duty cycle is controlled using a PID algorithm. This adjusts the current on LED D3 in real time to ensure its stability. This achieves closed-loop control of the LED, ensuring stable operating voltage and thus stable output light.

[0048] Furthermore, we can add closed-loop control to the software. The LED_PWM drive signal calculates the working power of the LED based on AD sampling, and controls the output signal of LED_PWM through PID algorithm to ensure the stability of LED_PWM output signal.

[0049] like Figure 7 The diagram shows the circuit diagram of the light source receiving module in the aerosol detection unit. The phototube ISO1 and surrounding components are used to receive the infrared light source signal after it is scattered by the aerosol. The received infrared light source signal is then amplified and filtered by the operational amplifier U4 and surrounding components, and then transmitted to the analog-to-digital conversion unit inside the MCU to be converted into an infrared digital signal. After data processing and analysis by the MCU, the aerosol content (i.e., the concentration of aerosol) is calculated.

[0050] like Figure 8 The diagram shows the circuit diagrams of the power supply voltage monitoring module and the ambient temperature monitoring module in the abnormal state monitoring unit. The left side shows the circuit diagram of the power supply voltage monitoring module, where resistors R38 and R41 form a voltage divider circuit. The MCU's analog-to-digital converter samples the voltage VBAT_V at this location to calculate the power supply voltage value. The right side shows the circuit diagram of the ambient temperature monitoring module, where resistor R37 and thermistor RT1 form a voltage divider circuit. By sampling the voltage NTC_V at this location and then converting it, the ambient temperature of the detection system of this invention is calculated. The temperature parameter is used to correct the aerosol value, ensuring the accuracy of the detection.

[0051] The present invention also provides an aerosol sensor detection device.

[0052] like Figure 9 The diagram shows the structure of an aerosol sensor detection device, including a main housing 1, a PCB support 2, a PCB board 3, and a bottom housing 4. The aerosol sensor detection system of this invention is arranged on the PCB board 3, which is fixed to the PCB support. The bottom housing 4 is installed and fixed to the main housing 1. The PCB support 2 and the PCB board 2 are fixed within the main housing 1 to form the aerosol sensor detection device of this invention.

[0053] Furthermore, to facilitate assembly, installation, and subsequent maintenance and disassembly, in this embodiment, the bottom shell 4 and the main shell 1 are fixed together by buckles and latches. Multiple sets of elastic buckles 401 are provided on the left and right sides of the bottom shell 4, and latches 101 that cooperate with the elastic buckles 401 are provided on the left and right sides of the main shell 1.

[0054] like Figure 10The diagram shows the internal structure of the main housing 1. The main housing 1 has an upper emitting optical path 103, an upper receiving optical path 104, and a scattering chamber 105 within its internal cavity. The upper emitting optical path 103 and the upper receiving optical path 104 are arranged at a V-shaped angle, with the V-angle ranging from 105° to 165° (e.g., ...). Figure 12 As shown in the diagram, the V-shaped angle is the scattering chamber 105, and an upper air inlet 102 is opened above the scattering chamber 105. Furthermore, a lower air inlet is opened on the bottom shell 4 perpendicular to the upper air inlet 102. At the same time, a lower air inlet pipe 402 is provided around the lower air inlet inside the bottom shell 4. Positioning holes are opened on the PCB bracket and the PCB board at the corresponding positions. The lower air inlet pipe 402 passes through the positioning holes into the scattering chamber 105. The lower air inlet is connected to the scattering chamber 105 through the lower air inlet pipe 402, thereby realizing the connection between the upper and lower airflows, which can facilitate the entry of aerosols or smoke into the scattering chamber from the upper and lower ends.

[0055] like Figure 11 The diagram shows the structure of the PCB support 2. The upper end of the PCB support 2 is equipped with a lower transmitting optical path 201, a lower receiving optical path 202, and a connector 203. Figure 12 As shown, the lower emitting optical path 201 is inserted into the upper emitting optical path 103 to form the emitting optical path, and the lower receiving optical path 202 is inserted into the upper receiving optical path 104 to form the receiving optical path. An infrared LED is positioned at the rear end of the emitting optical path and passes through the PCB bracket, where it is soldered to the lower PCB board. A photodiode is positioned at the rear end of the receiving optical path and passes through the PCB bracket, where it is soldered to the lower PCB board. A lens for focusing the light source is also arranged on the receiving optical path at the front end of the photodiode.

[0056] The structures of the upper and lower emitting optical paths, the upper and lower receiving optical paths, and the scattering chamber are customized and arranged according to requirements. In this invention, the structures of the upper and lower emitting optical paths and the upper and lower structural optical paths include U-shaped clamps. After the upper and lower U-shaped clamps are cross-clamped and fixed, a circular or elliptical emitting or receiving optical path is formed. The infrared light source is emitted from the emitting optical path. After being scattered by the scattering chamber, part of the light source enters the receiving optical path and is received by the phototube, thereby realizing the detection of the aerosol sensor.

[0057] Furthermore, such as Figure 9 As shown, connector 203 is located at the front end of PCB bracket 2 as a cable interface. It contains several pins that are soldered to PCB board 3. The connector and PCB bracket 2 are integrally formed, eliminating the need to purchase a separate connector and thus saving costs. Simultaneously, fixing holes are provided around the PCB bracket 2 and PCB board 3, and corresponding threaded holes are provided inside the main housing 1. Screws are used to engage with these threaded holes to fix the PCB bracket and PCB board inside the main housing 1.

[0058] like Figure 8As shown, both the main housing 1 and the bottom housing 4 have mesh-like through holes in the middle, which are used to allow aerosols to enter between the light-emitting tube and the receiving optical path inside the main housing, thereby detecting the concentration of aerosols. When aerosols enter between the light-emitting tube and the receiving optical path, the aerosols scatter the infrared light emitted by the light-emitting tube. Part of the scattered light is received by the phototube through the receiving optical path. The lens in the receiving optical path can increase the light intensity and increase the received signal of the phototube, thereby initially improving the signal strength. After passing through the operational amplifier circuit module of the light source receiving module, the signal is amplified, thereby improving the accuracy and precision of the aerosol sensor to a certain extent.

[0059] Because the infrared LED emitter employs closed-loop control in both hardware and software, it effectively ensures consistent light intensity emitted each time, thereby further improving the accuracy and precision of the aerosol sensor. To further enhance the accuracy of the aerosol sensor, the phototube undergoes continuous sampling, removing the maximum and minimum values ​​and taking the average as the sampling result. The detection device of this invention can be applied to aerosol detection, smoke detection, or dust detection in various fields.

[0060] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific 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 within the protection scope of the present invention.

Claims

1. An aerosol sensor detection system, characterized in that: The system includes a power conversion unit, a controller unit, an aerosol detection unit, a data interface unit, and an abnormal state monitoring unit. The power conversion unit provides the necessary stable driving voltage to the detection system. The aerosol detection unit collects analog signals of aerosol concentration in the environment. The controller unit is a system controller used to convert the analog aerosol concentration signals into digital signals and perform data processing. The data interface unit is used for interaction and data transmission with the host system. The abnormal state monitoring unit monitors the operating status of the system. The aerosol detection unit includes a light source emitting module and a light source receiving module. The light source emitting module includes a light-emitting diode (LED), and the light source receiving module includes a phototube. The LED and phototube are arranged at a V-shaped angle, and a lens is placed in front of the phototube. The LED achieves closed-loop control through hardware filtering and software filtering. The abnormal state monitoring unit includes a power supply detection circuit module and an ambient temperature detection module. The closed-loop control process of the LED through hardware filtering is as follows: Infrared LED D3 is driven by a PWM signal input through the LED_PWM port. The proportion of the PWM signal is adjusted. After the PWM signal is filtered by an RC filter composed of resistor R15 and capacitor C34, it controls the conduction of MOSFET Q7, thereby controlling the conduction of infrared LED D3 to emit infrared light. The PWM signal is input to the gate of MOSFET Q7 as its switch. The source of MOSFET Q7 is connected to a sampling resistor R20 and operational amplifier U5, and the drain of MOSFET Q7 is connected to infrared LED D3. Operational amplifier U5 and its peripheral circuits are used for impedance matching, forming a current sampling circuit. The source of MOSFET Q7 is connected to the non-inverting input of operational amplifier U5, and the output of operational amplifier U5 outputs the sampled current LED_Current. The MCU's AD module samples the current at LED_Current and outputs a voltage V. LC The current I at the infrared LED D3 led =I R20 =V LC / R20, based on the calculated current I led The current is compared with the target current, and the PWM duty cycle is controlled by the PID algorithm to adjust the current on the infrared LED D3 in real time to ensure its current stability. This achieves closed-loop control of the infrared LED to ensure the stability of the operating voltage of the infrared LED, thereby ensuring the stability of the output light source of the infrared LED. The process of achieving closed-loop control of the LED through software filtering is as follows: The LED_PWM drive signal calculates the working power of the LED based on AD sampling, and controls the LED_PWM drive signal through a PID algorithm to ensure the stability of the LED_PWM drive signal.

2. The aerosol sensor detection system as described in claim 1, characterized in that: The power conversion unit includes an EMC / EMI circuit module, a reverse connection protection circuit module, and a voltage regulator circuit module.

3. The aerosol sensor detection system as described in claim 1, characterized in that: The infrared LED driver module also includes a current detection circuit module for adjusting the current of the infrared LED.

4. The aerosol sensor detection system as described in claim 1, characterized in that: The light source receiving module is also equipped with a signal amplification circuit module for amplifying the aerosol concentration simulation signal.

5. The aerosol sensor detection system as described in claim 1, characterized in that: The data interface unit includes a CAN bus transceiver module.

6. An aerosol sensor detection device, characterized in that: The device includes a main housing, a PCB support, a PCB board, and a bottom housing. The aerosol sensor detection system according to any one of claims 1-5 is arranged on the PCB board. The PCB board is fixed on the PCB support, and the PCB support and the PCB board are fixed inside the main housing. The bottom housing is assembled and fixed with the main housing to form the detection device. The inner cavity of the main housing is provided with an upper emitting optical path, an upper receiving optical path, and a scattering chamber. The upper end of the PCB bracket is provided with a lower emitting optical path, a lower receiving optical path, and a connector. The lower emitting optical path is inserted into the upper emitting optical path to form an emitting optical path, and the lower receiving optical path is inserted into the upper receiving optical path to form a receiving optical path. The emitting optical path and the receiving optical path are arranged at a V-shaped angle, and a scattering chamber for aerosol diffusion is provided at the angle of the V-shape. The main housing has an upper air inlet above the scattering chamber, and the bottom housing has a lower air inlet below the upper air inlet. An air inlet pipe is provided around the lower air inlet on the bottom housing. The air inlet pipe passes through the PCB board and the PCB support to the scattering chamber and is connected to the scattering chamber to realize the upper and lower airflow of the aerosol sensor. Both the upper air inlet and the lower air inlet are provided with mesh-like through holes; The connector is integrally formed with the PCB bracket.

7. The aerosol sensor detection device as described in claim 6, characterized in that: The upper and lower emitting optical paths, as well as the upper and lower receiving optical paths, are each provided with a plurality of U-shaped clamps. The U-shaped clamps of the upper and lower emitting optical paths are interlocked to form the emitting optical path, and the U-shaped clamps of the upper and lower receiving optical paths are interlocked to form the receiving optical path.

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