Indoor air quality monitoring equipment and sensor cooperative control system

Abstract

The invention provides indoor air quality monitoring equipment and a sensor cooperative control system, relates to the technical field of indoor environment monitoring, and is used for solving the problems of response delay, temperature drift accumulation and alarm accessibility reduction in long-term operation of an air monitoring device. The device realizes feed-forward identification and closed-loop suppression of sample injection degradation, filter material pollution and dislocation, heat drift in the machine and acoustic attenuation: a sampling confirmation window is adaptively adjusted to reduce misjudgment, channel-level temperature drift compensation and power consumption derating are cooperatively executed according to priorities to realize steady-state temperature control, and a prompt link keeps subjective loudness consistent based on equivalent gain; meanwhile, the baseline is refreshed after maintenance to maintain long-term consistency; therefore, under the condition that the mechanical appearance is not changed, the monitoring accuracy, stability and alarm accessibility are remarkably improved, and the device-level design value of structural perception driving is highlighted.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of indoor environment monitoring, and in particular to an indoor air quality monitoring device and a sensor cooperative control system. BACKGROUND

[0002] The existing indoor air quality monitoring relies on environmental readings such as gas concentration, temperature and humidity to determine, and it is difficult to identify the potential influence of structural factors such as sample path change, filter state change, in-machine heating coupling and acoustic opening attenuation on the measurement and prompt link in a timely manner, resulting in problems such as response delay, temperature drift accumulation and alarm accessibility decline in long-term operation. The common practice in the industry is threshold alarm and regular calibration, and there is a lack of a general framework that quantifies structural influences as a unified calculable input and controls online. SUMMARY

[0003] In view of the defects in the prior art, the present application provides an indoor air quality monitoring device and a sensor cooperative control system.

[0004] To solve the above technical problems, the present application provides an indoor air quality monitoring device and a sensor cooperative control system, which comprises a base and a shell, and the front end of the shell forms an arc-shaped mounting groove; a filter screen is detachably arranged in the arc-shaped mounting groove, a first magnetic block is arranged on the filter screen support, a second magnetic block is arranged at intervals on the arc-shaped front edge of the shell, and the first magnetic block and the second magnetic block are oppositely adsorbed and positioned; a carbon dioxide sensor is arranged in a sensing cavity behind the arc-shaped mounting groove; two pressure taking ends of a double-cavity differential pressure sensor are respectively connected to a front cavity outside the filter screen and a rear cavity inside the filter screen through capillary tubes; an optical reflection transmitter and an optical reflection receiver are coaxially arranged inside the arc-shaped mounting groove, forming an optical reflection device, and the optical path thereof passes through the filter screen; a filter screen in-place angle sensor is arranged on the filter screen support close to the first magnetic block; an inner temperature sensor is arranged on the sensing cavity or a metal support thereof, and an outer temperature sensor is arranged at an air inlet upstream or an outside opening of the shell; a power detection module is connected in series in a heating or main energy consumption circuit of the device; a buzzer is arranged at a corresponding loudspeaker hole on the rear end face of the shell, and an acoustic sampling sensor is arranged inside the loudspeaker hole and axially aligned with the buzzer; a mainboard is electrically connected with each of the sensors and modules, and is configured to calculate a structural parameter according to the measured electrical signals and execute a control state machine with the parameter as an input.

[0005] As preferred, the optical alignment emitter is coaxial with the optical axis of the optical alignment receiver and its optical path only passes through the effective area of the filter screen, the inside of the arc-shaped mounting slot is provided with a light shielding structure to suppress stray incidence, the main board stores the constants κ and γ related to the optical parameter calibration of the filter screen and the reference light intensity I0, the κ and γ are fixed in the non-volatile memory, and the I0 is updated after the filter screen is cleaned or replaced and is called by the main board as the baseline parameter of optical measurement.

[0006] As preferred, the first pressure taking end and the second pressure taking end of the double-cavity differential pressure sensor are respectively communicated to the front cavity outside the filter screen and the rear cavity inside the filter screen through independent capillary guide tubes, the capillary guide tubes are routed along the inner wall of the shell and avoid the internal heat source and the optical path area of the optical alignment device, the main board collects the micro-pressure difference signal at a frequency not less than five times per second, and extracts the representative value of instantaneous measurement by sliding median or percentile, while saving the reference pressure difference ΔPref and the maximum allowed pressure difference ΔPmax in the non-volatile memory for calling by the normalization operation.

[0007] As preferred, the carbon dioxide sensor is used to output a concentration time sequence, the main board opens an event window and performs fitting calculation when detecting a concentration step change, the sampling frequency of the carbon dioxide sensor is not less than one time per second, the main board calculates the equivalent sampling diffusion time constant according to the data of two time points t1 and t2, and the time constant is calculated by the following formula: , wherein C∞ is the steady-state concentration, C(t1) and C(t2) are the concentration sampling values at the corresponding time points, and the calculation is performed with abnormal point suppression and parameter update in the event window.

[0008] As preferred, the internal temperature sensor and the external temperature sensor are respectively connected to the main board through independent buses, the power detection module is a shunt resistance sampling circuit or a power metering chip and is electrically connected to the analog-to-digital conversion unit of the main board, the main board calculates the equivalent thermal resistance Rth equal to (Ts-Tenv) / P according to Ts and Tenv and the equivalent power P, the acoustic sampling sensor outputs the root mean square sound pressure at an internal sampling rate not less than 8 kHz and is used together with the root mean square value of the driving voltage of the buzzer to calculate the acoustic gain, and the acoustic link calibration coefficient is stored in the non-volatile memory of the main board.

[0009] A sensor cooperative monitoring system of an indoor air quality monitoring device, the system comprising an indoor air quality monitoring device, a processor, and a memory; The indoor air quality monitoring device comprises: a detachable filter screen arranged in an arc-shaped mounting slot, a first magnetic block and a second magnetic block positioned opposite to the filter screen, a carbon dioxide sensor arranged in a sensing cavity behind the arc-shaped mounting slot, a double-cavity differential pressure sensor with two pressure taking ends respectively connected to a front cavity outside the filter screen and a rear cavity inside the filter screen through independent capillary guide tubes, an optical transmitting-receiving emitter and receiver coaxially arranged and with an optical path passing through the filter screen, a filter screen in-place angle sensor arranged at a filter screen support close to the first magnetic block, an internal temperature sensor attached to the sensing cavity or a metal support thereof, an external temperature sensor arranged at an upstream or lateral opening of an air inlet of the housing, a power detection module connected in series to a heating or main energy consumption circuit, a buzzer arranged at a loudspeaker hole of a rear end surface of the housing, and an acoustic sampling sensor located inside the loudspeaker hole and axially aligned with the buzzer. The processor is electrically connected with the memory and the carbon dioxide sensor, the double-cavity differential pressure sensor, the optical transmitting-receiving emitter and receiver, the filter screen in-place angle sensor, the internal temperature sensor, the external temperature sensor, the power detection module, the buzzer and the acoustic sampling sensor. The memory stores program instructions running on the processor, and the processor is configured to: acquire electrical signals from the sensors and modules and calculate a set of structural parameters, the set of structural parameters comprising a filter screen in-place deviation angle, an equivalent sampling diffusion time constant based on a concentration time series, a filter screen optical porosity based on a transmitted light intensity and a calibration constant, a clogging index based on a cross-filter screen micro pressure difference and a reference pressure difference and a maximum allowable pressure difference, an equivalent thermal resistance calculated from the internal temperature and the external temperature and an equivalent power, and an acoustic gain calculated from the acoustic sampling signal, a buzzer driving voltage and an acoustic link calibration coefficient; and execute a control state machine with the set of structural parameters as input, the control state machine being configured to generate control signals according to a preset threshold and a mapping pair for a sampling confirmation time window management, a channel level temperature compensation parameter calculation, a display screen brightness and a wireless transmission duty cycle and a buzzer duty cycle descending order control, and a maintenance and in-place prompting control, and send the control signals to the display screen, the wireless communication interface and the buzzer respectively.

[0010] Preferably, the optical axes of the optical transmitting-receiving emitter and receiver are coaxial and their optical paths only pass through the effective area of the filter screen, a light shielding structure is arranged inside the arc-shaped mounting slot, the memory stores calibration constants κ and γ and a reference light intensity I0 related to optical measurement, the processor is configured to calculate the filter screen optical porosity according to the mapping relationship of I and I0 and support baseline refreshing of I0 after filter screen replacement, and κ and γ are solidified in a non-volatile storage space for calling.

[0011] As preferred, the carbon dioxide sensor outputs a concentration time series at a frequency not less than once per second, the processor is configured to open an event window and perform a fitting calculation when a step change in concentration is detected, to calculate a time constant from the sampling values and steady-state values at two time instants t1 and t2, and to suppress outliers and parameter stabilization within the event window, the threshold value for determining a step trigger, the window length and the minimum number of valid samples are stored in the memory and can be updated by the processor.

[0012] As preferred, the first pressure taking end and the second pressure taking end of the dual-cavity differential pressure sensor are respectively communicated to the front cavity outside the filter screen and the rear cavity inside the filter screen through independent capillary guide tubes, the capillary guide tubes are routed along the inner wall of the shell and avoid the internal heat source and the light path area of the optical alignment device, the processor collects the micro pressure difference signal at a frequency not less than five times per second and performs representative value extraction of the sliding median or percentile, the reference pressure difference ΔPref and the maximum allowed pressure difference ΔPmax and the window length for sampling and smoothing are stored in the memory and read by the processor during operation.

[0013] As preferred, the internal temperature sensor and the external temperature sensor are respectively connected to the processor through independent buses, the power detection module is a shunt resistance sampling circuit or a power metering chip and is electrically connected to the analog-to-digital conversion unit of the processor, the processor is configured to calculate the equivalent thermal resistance according to the internal and external temperatures and the equivalent power and generate a parameter set for channel-level temperature compensation and resource scheduling, while storing the control priority order of the display screen brightness, the wireless transmission duty cycle and the buzzer duty cycle and the corresponding threshold table in the memory and outputting control signals in the order and threshold table when the state machine is running.

[0014] Compared with the related art, the indoor air quality monitoring device and the sensor cooperative control system provided by the application have the following beneficial effects: The application preposes the structural side influence as the first type of input and parameterizes uniformly, and the device realizes the feedforward identification and closed-loop suppression of sampling degradation, filter contamination and misplacement, internal thermal drift and acoustic attenuation: the sampling confirmation window is adaptively adjusted to reduce false positives, channel-level temperature drift compensation and power reduction are cooperatively executed according to priority to stabilize the temperature, the prompt link maintains the subjective loudness consistent based on the equivalent gain, and the baseline is refreshed after maintenance to maintain long-term consistency; thereby, without changing the mechanical shape, the monitoring accuracy, stability and alarm accessibility are significantly improved, highlighting the value of device-level design driven by structural perception. BRIEF DESCRIPTION OF DRAWINGS

[0015] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings: Figure 1 A perspective view of the device according to the present application; Figure 2 Another perspective view of the device according to the present application; Figure 3 A perspective view of the device according to the present application; Figure 4 A perspective view of the device according to the present application; Figure 5 A perspective view of the device according to the present application;

[0016] In the drawings: 100 - indoor air quality monitoring device; 1 - base; 2 - housing; 3 - switch; 4 - display screen; 5 - filter screen; 6 - first magnetic block; 7 - second magnetic block; 8 - mounting seat; 9 - electrochemical sensor; 10 - semiconductor sensor; 11 - carbon dioxide sensor; 12 - power supply; 13 - buzzer; 14 - main board; 15 - double-cavity differential pressure sensor; 16 - filter screen in place angle sensor; 17 - optical reflection transmitter; 18 - optical reflection receiver; 19 - internal temperature sensor; 20 - external temperature sensor; 21 - acoustic sampling sensor. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0018] The terms used in this disclosure are merely for the purpose of describing particular embodiments and are not intended to limit the disclosure. The singular forms "a," "an," and "the" used in this disclosure and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0019] It should be understood that, although the terms first, second, third, etc. can be employed in this disclosure to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another type of information. For example, without departing from the scope of the disclosure, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information. Depending on the context, the word "if' as used herein can be interpreted as "when" or "upon" or "in response to determining".

[0020] Embodiments, with reference to Figures 1 to 4 The indoor air quality monitoring device 100 according to the embodiments of the present application comprises a base 1, a shell 2, a display screen 4, a switch 3, a mainboard 14, a power supply 12, a buzzer 13 and a monitoring assembly.

[0021] Specifically, the shell 2 is fixed on the base 1 to form the main structure of the device. The front end face of the shell 2 is provided with an arc-shaped mounting groove for accommodating the filter screen 5. In order to realize the detachable installation of the filter screen 5, a plurality of second magnetic blocks 7 are equidistantly arranged on the front end edge of the arc-shaped mounting groove. The filter screen 5 itself or its bracket is provided with a first magnetic block 6 matched with the second magnetic block 7. Through the magnetic attraction cooperation of the first magnetic block 6 and the second magnetic block 7, the filter screen 5 can be conveniently and detachably installed in the arc-shaped mounting groove. This magnetic attraction installation mode not only facilitates the user to replace the filter screen, but also provides a structural basis for subsequent angle sensing of the filter screen in place.

[0022] The rear end face and both sides of the shell 2 are provided with heat dissipation holes for heat dissipation inside the device to ensure the normal working temperature of the electronic components. The rear end face of the shell 2 is also provided with a loudspeaker hole corresponding to the position of the buzzer 13 for the buzzer 13 to emit a prompt sound. One side of the rear end face of the shell 2 is provided with a charging port which is electrically connected with the power supply 12 inside the device for power supply or charging of the device. The mainboard 14 as the control core of the device is electrically connected with the switch 3, the display screen 4, the monitoring assembly, the power supply 12 and the buzzer 13 respectively, and is responsible for receiving sensor data, processing control logic, driving display and prompting and other functions.

[0023] The core of the present application lies in the composition of the monitoring assembly and the structure sensing control based on the device structure. The monitoring assembly comprises the following sensors and modules: The carbon dioxide sensor 11 is arranged in the sensing cavity behind the arc-shaped mounting groove, and is used to obtain the concentration time sequence C(t) of carbon dioxide in the air. The carbon dioxide sensor 11 is not only used for conventional concentration monitoring in the present application, but also used for calculating the equivalent sampling diffusion time constant to characterize the integrity and response delay of the sampling channel.

[0024] In some embodiments, the carbon dioxide sensor can be an infrared absorption sensor.

[0025] Double-chamber differential pressure sensor 15: its first pressure-taking end communicates with the front chamber outside the filter screen 5 through a capillary lead pipe, and the second pressure-taking end communicates with the rear chamber inside the filter screen 5 through another capillary lead pipe. The sensor is used to output the micro pressure difference between the two sides of the filter screen 5 in real time . is a key parameter for evaluating the degree of filter screen blockage, which is used to calculate the micro pressure difference blockage index .

[0026] In a preferred embodiment, the double-chamber differential pressure sensor 15 is laid through two capillary lead pipes to the inner walls of the front and rear chambers of the filter screen, respectively, and the lead pipes are routed along the inner wall of the shell and avoid heat sources and optical paths to reduce flow resistance addition and measurement crosstalk, ensuring the accuracy of micro pressure difference measurement.

[0027] Filter screen in-place angle sensor 16: fixed on the filter screen support near the first magnetic block 6, used to output two magnetic induction intensity vectors B1, B2. The sensor can sense the installation posture of the filter screen 5, judge whether the filter screen is correctly in place or has deviation, and is used to calculate the filter screen in-place deviation angle .

[0028] In a preferred embodiment, the filter screen in-place angle sensor 16 records , as a reference vector after the device is assembled, and compares the current vector during the power-on self-test stage to determine whether it is out of limit, so as to realize real-time monitoring of the in-place state of the filter screen.

[0029] Optical reflection detector: including optical reflection transmitter 17 and optical reflection receiver 18. They are coaxially arranged inside the arc-shaped mounting groove, and their light paths penetrate the filter screen 5, used to output the transmission light intensity I. The transmission light intensity I is a key parameter for evaluating the optical porosity of the filter screen, which is used to calculate the optical porosity of the filter screen , so as to represent the pollution and shielding degree of the filter screen.

[0030] In a preferred embodiment, the optical reflection transmitter 17 and the optical reflection receiver 18 are coaxially installed inside the arc-shaped mounting groove, and the light path only penetrates the filter screen and adopts a dispersion-suppressed light shield to suppress external light interference and stabilize the measurement of I, improving the measurement accuracy.

[0031] Internal temperature sensor 19: attached to the sensing chamber or its metal support, used to output the side temperature Ts of the sensing chamber. Ts is an important parameter for evaluating the internal thermal state of the device, which is used together with the external temperature sensor 20 and the power detection module to calculate the equivalent thermal resistance Rth of the sensor chamber and the mainboard.

[0032] In a preferred embodiment, the inner temperature sensor 19 is adhered to the sensing chamber metal member by a heat-conductive glue to ensure good thermal contact and accurate temperature measurement.

[0033] The outer temperature sensor 20 is arranged on the outside of the shell 2 or upstream of the air inlet to output the ambient temperature Tenv. Tenv is an important parameter for evaluating the thermal environment outside the device and is used together with the inner temperature sensor 19 and the power detection module to calculate the equivalent thermal resistance Rth.

[0034] In a preferred embodiment, the outer temperature sensor 20 is located at a position upstream of the air inlet or outside the shell to accurately reflect the ambient temperature. The inner temperature sensor 19 and the outer temperature sensor 20 are respectively connected to the main board 14 through independent buses to reduce the measurement phase difference caused by cross-thermal capacity and improve the independence and accuracy of temperature measurement.

[0035] The acoustic sampling sensor 21 is arranged inside the rear speaker hole and faces the buzzer 13 to output the root mean square sound pressure prms. prms is a key parameter for evaluating the prompting effect of the buzzer and is used together with the root mean square value of the driving voltage Vrms of the buzzer 13 to calculate the acoustic gain Gac of the buzzer directivity.

[0036] In a preferred embodiment, the acoustic sampling sensor 21 is located at the geometric center of the rear speaker hole and is axially aligned with the buzzer 13 to improve the consistency of picking up prms and reduce the measurement deviation caused by structural directivity, ensuring the accuracy of acoustic gain calculation.

[0037] The power detection module is connected in series to the heating or main energy consumption circuit to output the equivalent power P. P is an important parameter for evaluating the power of the internal heat source of the device and is used together with the inner temperature sensor 19 and the outer temperature sensor 20 to calculate the equivalent thermal resistance Rth.

[0038] In a preferred embodiment, the power detection module uses a shunt resistor or a power metering chip connected in series to the heating or main energy consumption circuit. The detection signal is collected by the analog-to-digital conversion unit of the main board 14 for real-time calculation of the equivalent power P.

[0039] The device is configured for structure-aware control based on the structure of the device. Without changing the relative positions of the shell and components, the device can generate structure parameters for control and maintenance and drive control logic using the structural conditions determined by the arc-shaped sampling slot, magnetic filter screen, double-cavity differential pressure structure, heat dissipation hole and component thermal path, and rear speaker hole. This means that the invention not only simply integrates sensors, but also uses the physical structure of the device itself as the basis for sensing and control, forming a smart adaptive system.

[0040] In some embodiments, the device can also include electrochemical sensor 9 and semiconductor sensor 10. Both are accessed to main board 14 as subsidiary parameters, and are used to maintain hints or environmental context corroboration, but do not participate in the calculation of the above-mentioned structural parameters and the structural awareness control decision. This means that they can provide additional air quality information, but will not affect the core of the structural awareness control logic of the invention.

[0041] The present invention calculates a series of structural parameters reflecting the structural state of the device from the raw data acquired by the above-mentioned monitoring components. These structural parameters at least include: Deviation angle of filter screen in place : the deviation angle of filter screen 5 from the ideal installation surface, calculated from the two magnetic induction intensity vectors B1, B2 output by filter screen in place angle sensor 16 and its assembly reference vector , . Specifically, is equal to the value of the inverse cosine function, whose argument is the dot product of vector difference (B1− ) and (B2− ) divided by the product of the norms of the two vectors; where the dot product is used to represent the relative orientation of the two vectors, and the norm is used for normalization, in radian. This parameter is used to determine whether the filter screen 5 is in place.

[0042] Equivalent sample diffusion time constant : obtained by fitting the step response of the concentration time series C(t) acquired by carbon dioxide sensor 11. Specifically, determined by a first-order response model, which satisfies: ; where C0 is the initial value and C∞ is the steady-state value. Optionally, two time points t1, t2, is equal to (t2−t1) divided by the ratio of (C∞−C(t1)) to (C∞−C(t2)) in natural logarithm. to reflect the integrity and response delay of the sampling channel.

[0043] In a preferred implementation, the fitting is triggered to open an event window by detecting a sudden increase or decrease in carbon dioxide concentration, and within the window, robust fitting or sliding median is used to suppress abnormal points, in order to improve the stability of . The sampling frequency of carbon dioxide sensor 11 is not less than one per second, and the event window duration of is not less than thirty seconds, to ensure that there are enough data points for accurate fitting.

[0044] Optical porosity of filter screen : obtained by calibrating the ratio of transmitted light intensity I output by optical transmission detector to reference light intensity I0. Specifically, is calculated from The result is that κ and γ are factory calibration constants, and I0 is the reference light intensity in the state with or without a filter. Used to characterize the degree of filter contamination and obstruction.

[0045] In a preferred embodiment, the optical through-beam detector is factory-calibrated with I and ρopt, the calibration constants κ and γ are stored in non-volatile memory, and I0 serves as a baseline after filter cleaning or replacement and can be updated during operation to adapt to the new state after filter aging or replacement.

[0046] Micro-pressure differential blockage index The value is calculated based on the normalized values ​​of ΔP(t) output by the dual-chamber differential pressure sensor 15, the reference pressure difference ΔPref, and the maximum permissible pressure difference ΔPmax. Specifically, Depend on The value range is limited to between zero and one. ΔPref is calibrated under clean filter conditions, and ΔPmax is the maximum micro-pressure difference allowed by the structural design. Used to trigger filter maintenance and sampling strategy adjustments.

[0047] In a preferred embodiment, The calculation uses the moving median or percentile of ΔP(t) as a representative value to suppress the impact of short-term disturbances on the congestion index. The sampling frequency of the dual-chamber differential pressure sensor is no less than five times per second to capture the dynamic changes of micro-pressure differences.

[0048] The equivalent thermal resistance Rth between the sensor cavity and the motherboard is calculated based on the temperature difference between Ts output by the internal temperature sensor 19 and Tenv output by the external temperature sensor 20, and the equivalent power P output by the power detection module. Specifically, Rth = (Ts − Tenv) / P. Rth is used for temperature drift compensation and power derating.

[0049] In a preferred embodiment, the power detection module calculates the equivalent power P based on the shunt resistor voltage drop or the output of the power metering chip, and uses it in conjunction with Ts and Tenv to estimate Rth online and trigger derating control. The sampling frequency of the internal and external temperature sensors is no less than twice per second.

[0050] f) Buzzer directional acoustic gain Gac: Calculated based on the prms output by the acoustic sampling sensor 21, the root mean square value of the driving voltage Vrms of the buzzer 13, and the acoustic link calibration coefficient Kmic. Specifically, Gac = Kmic·(prms / Vrms). Gac is used to achieve equal-perceived loudness cues based on the characteristics of the device's aperture array.

[0051] In a preferred embodiment, the internal sampling frequency of the acoustic sampling sensor 21 is not less than 8 kHz and outputs the root mean square sound pressure. The acoustic sampling sensor 21 obtains Kmic through one-time calibration and reviews the stability of Gac when the buzzer 13 is driven by a standard test tone, which is used to evaluate whether the speaker hole is blocked or the structure is deformed.

[0052] With reference to Figure 5 , the embodiment of the present application provides an indoor air quality monitoring and control method based on device structure, which is applied to the device described in the above embodiment one and embodiment two. The method comprises the following steps: S1 structure parameter acquisition: the device continuously collects B1, B2, C(t), I, ΔP(t), Ts, Tenv, prms, Vrms, P, etc. original sensor data. The mainboard 14 calculates the structure parameters such as 、 、 、 , Rth, Gac, etc. according to the preset algorithm and model using these original data. The calculation process is as described above.

[0053] S2 intake integrity evaluation: the mainboard 14 comprehensively calculates a structure health index Iintake based on the calculated 、 、 、 structure parameters. Iintake is a comprehensive index for evaluating the overall health status of the device's intake channel and filter screen. When Iintake exceeds the preset threshold, it indicates that there may be problems with the intake integrity, such as filter screen blockage, intake channel obstruction, filter screen misalignment, etc. At this time, the mainboard 14 will prolong the measurement reconfirmation time window and freeze the linkage to the downward trend. This means that when the intake integrity is damaged, the device will be more cautious about changes in air quality data to avoid false judgments caused by structural problems.

[0054] In a preferred embodiment, the structure health index Iintake is obtained by normalizing and weighting the sum of each parameter, and the weights satisfy and are one, and the weights of and are monotonically increasing mapping, and the weights of 1− and are monotonically increasing mapping, to ensure that Iintake can accurately reflect the degradation degree of the intake integrity. When Iintake is at a low level for a long time and and are in the normal interval, the reconfirmation time window is shortened to improve real-time performance; when Iintake rises, the reconfirmation time window is prolonged to reduce the risk of false judgment.

[0055] S3 Thermal Coupling Compensation and Power Reduction: The mainboard 14 continuously monitors Rth and P and calculates the rate of change of the mainboard proximal temperature. When Rth multiplied by P or Rth multiplied by the rate of change of the mainboard proximal temperature exceeds a preset threshold, it indicates that the internal thermal environment of the device has changed significantly, which may cause the sensor to drift. At this time, the mainboard 14 performs temperature drift compensation on the gas measurement value to correct the measurement error caused by temperature change. At the same time, in order to reduce the internal thermal load, the mainboard 14 reduces the brightness of the display screen 4, the duty cycle of wireless transmission and the prompt duty cycle of the buzzer 13 according to priority, thereby achieving power consumption reduction scheduling. In a preferred embodiment, the temperature drift compensation satisfies: for the original measurement value zi of the ith channel, after compensation, zi'=zi−βi·Rth·(the rate of change of the mainboard proximal temperature), where βi is the temperature drift sensitivity coefficient of the corresponding channel.

[0056] S4 Acoustic Equivalent Sensing Driving: The mainboard 14 calculates the driving voltage required for the buzzer 13 according to the calculated Gac and the currently detected abnormality level. By dynamically adjusting the driving voltage of the buzzer 13, the loudness perceived by the user end remains constant, ensuring the effectiveness of the prompt sound even if the speaker hole is blocked or the internal acoustic environment of the device changes.

[0057] In a preferred embodiment, the combination strategy of short beep and display screen prompt during night or quiet period is adaptively selected based on Gac and environmental noise, and user confirmation events are recorded to optimize subsequent acoustic driving voltage, achieving more intelligent prompting.

[0058] S5 Maintenance and In-Position Prompting: The mainboard 14 continuously monitors , and . When is lower than a preset threshold, it indicates that the filter screen is blocked or severely contaminated, or is higher than a preset threshold, it indicates that the filter screen is blocked, or is out of limits, it indicates that the filter screen is not in the correct position, the mainboard 14 will issue a filter screen cleaning and replacement or position correction prompt through the display screen 4 and / or the buzzer 13. After the user completes the maintenance operation, the device will automatically refresh I0, the baseline and to adapt to the new filter screen state, ensuring the accuracy of subsequent monitoring.

[0059] The mainboard 14 is configured to execute a control state machine with structural parameters as input. The state machine includes at least normal state, sampling degradation state, thermal drift state, filter screen mispositioning state and maintenance state, and at least one of sampling confirmation extension, temperature drift compensation, power reduction, in-position prompting and maintenance guidance is executed according to the state transition conditions. For example, when is out of limits, the state machine enters the filter screen mispositioning state and triggers the in-position prompt; when or When the limit is exceeded, the state machine enters a maintenance state, triggering maintenance guidance; when Rth or P is abnormal, the state machine enters a thermal drift state, triggering temperature drift compensation and power reduction; when When the limit is exceeded, the state machine enters a maintenance state, triggering maintenance guidance; when Rth or P is abnormal, the state machine enters a thermal drift state, triggering temperature drift compensation and power reduction; when

[0060] The application also provides an indoor air quality monitoring system, comprising a processor, a memory and the indoor air quality monitoring device described in the above embodiments. The memory stores instructions for running on the processor, which makes the processor execute the indoor air quality monitoring and control method described in Embodiment Three. The processor can be a microcontroller on the mainboard 14 or a more powerful processing unit. The memory can be a non-volatile storage medium such as ROM, RAM, flash memory, etc.

[0061] The application also provides a computer-readable storage medium storing a computer program. When the program is executed by the processor, the steps of the indoor air quality monitoring and control method described in Embodiment Three are implemented. The computer-readable storage medium can be a U disk, a mobile hard disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a magnetic tape, a floppy disk, an optical data storage device, etc.

[0062] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the application, but not to limit them; although the application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for some technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the application. The formulas involved in the application are all de-dimensioned (such as standardized means), and are obtained by software simulation optimization based on a large amount of sensor measured data, which can truly reflect the relationship between air quality parameters; the preset parameters in the formulas are flexibly set by those skilled in the art according to the actual monitoring scene.

[0063] The above embodiments can be realized by software, hardware, firmware or any combination thereof. When realized by software, it can be embodied as a computer program product, which contains computer instructions loaded and executed, and can generate data analysis, early warning control and other processes and functions of air quality monitoring. The computer instructions can be stored in semiconductor media such as flash memory, EEPROM, solid state disk, or magnetic media such as mobile hard disk, magnetic disk, or optical media such as optical disk, and can be transmitted by wired or wireless (such as infrared, microwave) way.

[0064] The execution sequence of each process is determined by air quality data processing logic and early warning response requirements, and is not limited by the serial number. The units and algorithm steps of the present application can be realized by electronic hardware or a combination of hardware and software, and the specific mode depends on the design constraints such as sensor coordination accuracy and response speed, and the related implementation modes are within the protection scope of the present application.

[0065] The unit division of the system device is logical function division, which can be integrated or distributed in actual implementation; the modules are indirectly coupled and communicated through electrical interfaces and the like. When the functions are realized in the form of software units and sold independently, they can be stored in a U disk, a ROM, a RAM and the like computer readable medium, and the included instructions can make the device execute the core steps such as data fusion, dynamic threshold calculation and hierarchical early warning.

[0066] Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any variations, uses or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice in the art to which the application pertains. It is intended that the specification and examples be considered exemplary only, with the true scope and spirit of the application being indicated by the following claims.

[0067] It should be understood that the present application is not limited to the precise construction that has been described above and illustrated in the accompanying drawings, and that various modifications and changes can be made without departing from the scope thereof. The only scope of the present application is limited by the appended claims.

Claims

1. An indoor air quality monitoring device, characterized in that, Including base and shell, the front end of the shell forms an arc-shaped mounting slot; The arc-shaped mounting slot is detachably provided with a filter screen support, the filter screen support is provided with a first magnetic block, the arc-shaped front edge of the shell is provided with a second magnetic block at intervals, the first magnetic block and the second magnetic block are oppositely adsorbed and positioned; The carbon dioxide sensor is arranged in the sensing cavity behind the arc-shaped mounting slot; the two pressure taking ends of the double-cavity differential pressure sensor are respectively connected to the front cavity outside the filter screen and the rear cavity inside the filter screen through capillary guide tubes; The optical transmitter and the optical receiver are coaxially arranged inside the arc-shaped mounting slot, and constitute an optical alignment device, and the optical path of the optical alignment device passes through the filter screen; the filter screen in-place angle sensor is arranged at the filter screen support close to the first magnetic block; The inner temperature sensor is arranged on the sensing cavity or its metal support, and the outer temperature sensor is arranged at the upstream or outside opening of the air inlet of the shell; The power detection module is connected in series in the heating or main energy consumption circuit of the device; the buzzer is arranged at the back end of the shell corresponding to the loudspeaker hole, and the acoustic sampling sensor is arranged inside the loudspeaker hole and axially aligned with the buzzer; The main board is electrically connected with each sensor and module, and is configured to calculate the structural parameters according to the measured electrical signals and execute the control state machine with the parameters as input.

2. The indoor air quality monitoring device of claim 1, wherein, The optical axes of the optical transmitter and the optical receiver are coaxial, and the optical path of the optical transmitter and the optical receiver only passes through the effective area of the filter screen, a light shielding structure is arranged inside the arc-shaped mounting slot to suppress stray incidence, the main board stores constants κ and γ related to filter screen optical parameter calibration and reference light intensity I0, κ and γ are fixed in non-volatile memory, I0 is updated after the completion of filter screen cleaning or replacement and is called by the main board as the baseline parameter of optical measurement.

3. The indoor air quality monitoring device of claim 1, wherein, The first pressure taking end and the second pressure taking end of the double-cavity differential pressure sensor are respectively connected to the front cavity outside the filter screen and the rear cavity inside the filter screen through independent capillary guide tubes, the capillary guide tubes are routed along the inner wall of the shell and avoid internal heat sources and the optical path area of the optical alignment device, the main board collects the differential pressure signal at a frequency of not less than five times per second, extracts the representative value of instantaneous measurement by sliding median or percentile, and saves the reference differential pressure ΔPref and the maximum allowed differential pressure ΔPmax in the non-volatile memory for normalization operation calling.

4. The indoor air quality monitoring device of claim 1, wherein, The carbon dioxide sensor is used to output a concentration time sequence, the mainboard opens an event window and performs a fitting calculation when detecting a concentration step change, the sampling frequency of the carbon dioxide sensor is not less than once per second, the mainboard calculates an equivalent sampling diffusion time constant according to data of two time points t1 and t2, and the diffusion time constant is calculated by the following formula: Wherein C∞ is a steady-state concentration, C(t1) and C(t2) are concentration sampling values at corresponding time points, and the calculation performs abnormal point suppression and parameter updating in the event window.

5. The indoor air quality monitoring device of claim 1, wherein, The inner temperature sensor and the outer temperature sensor are respectively connected with the main board through independent buses, the power detection module is a shunt resistance sampling circuit or a power metering chip and is electrically connected with the analog-to-digital conversion unit of the main board, the main board calculates the equivalent thermal resistance Rth equal to (Ts-Tenv) / P according to Ts, Tenv and equivalent power P, and the acoustic sampling sensor outputs the root mean square sound pressure at an internal sampling rate of not less than 8 kHz and is used together with the root mean square value of the driving voltage of the buzzer to calculate the acoustic gain.

6. A sensor coordination control system of an indoor air quality monitoring device, characterized by, The system comprises an indoor air quality monitoring device, a processor, and a memory. The indoor air quality monitoring device comprises: a detachable filter screen arranged in the arc-shaped mounting groove, a first magnetic block and a second magnetic block positioned opposite the filter screen, a carbon dioxide sensor arranged in a sensing cavity behind the arc-shaped mounting groove, a double-cavity differential pressure sensor with two pressure taking ends respectively connected to a front cavity outside the filter screen and a rear cavity inside the filter screen through independent capillary guide tubes, an optical opposite-emitting transmitter and an optical opposite-receiving receiver coaxially arranged and with a light path passing through the filter screen, a filter screen in-place angle sensor arranged at a filter screen support close to the first magnetic block, an internal temperature sensor attached to the sensing cavity or a metal support thereof, an external temperature sensor arranged at an upstream or outside opening of an air inlet of the shell, a power detection module connected in series to a heating or main energy consumption circuit, a buzzer arranged at a position corresponding to a loudspeaker hole at a rear end face of the shell, and an acoustic sampling sensor located inside the loudspeaker hole and axially aligned with the buzzer. The processor is electrically connected with the memory and the carbon dioxide sensor, the double-cavity differential pressure sensor, the optical opposite-emitting transmitter and the optical opposite-receiving receiver, the filter screen in-place angle sensor, the internal temperature sensor, the external temperature sensor, the power detection module, the buzzer and the acoustic sampling sensor. The memory stores program instructions running on the processor, and the processor is configured to: acquire electrical signals from the sensors and the modules and calculate a set of structure parameters, the set of structure parameters comprising a filter screen in-place deviation angle, an equivalent sampling diffusion time constant based on a concentration time series, a filter screen optical porosity based on a transmitted light intensity and a calibration constant, a clogging index based on a cross-filter screen micro pressure difference and a reference pressure difference and a maximum allowable pressure difference, an equivalent thermal resistance calculated from an internal temperature and an external temperature and an equivalent power, and an acoustic gain calculated from an acoustic sampling signal, a buzzer driving voltage and an acoustic link calibration coefficient; and execute a control state machine as input, the control state machine being configured to generate control signals according to preset threshold values and mapping for sampling confirmation time window management, channel level temperature compensation parameter calculation, display screen brightness and wireless transmission duty cycle and buzzer duty cycle step-down sequencing control, and maintenance and in-place prompting control, and send the control signals to the display screen, the wireless communication interface and the buzzer respectively.

7. The sensor coordination control system of an indoor air quality monitoring device according to claim 6, wherein, The optical axes of the optical opposite-emitting transmitter and the optical opposite-receiving receiver are coaxial, and the light path thereof passes through only the effective area of the filter screen, a light shielding structure is arranged inside the arc-shaped mounting groove, the memory stores calibration constants κ and γ and a reference light intensity I0 related to optical measurement, and the processor is configured to calculate the filter screen optical porosity according to the mapping relationship of I and I0 and support baseline refreshing of I0 after replacement of the filter screen, and κ and γ are fixed in a non-volatile storage space for calling.

8. The sensor coordination control system of an indoor air quality monitoring device according to claim 6, wherein, The carbon dioxide sensor outputs a concentration time series at a frequency not less than once per second, the processor is configured to start an event window and perform a fitting calculation when a step change in concentration is detected, to calculate the time constant of the sampling values and the steady-state value at two time points t1 and t2, and to suppress outliers and parameter stabilization processing within the event window, the threshold value for determining the step trigger, the window length and the minimum number of valid samples are stored in the memory and can be called and updated by the processor.

9. The sensor coordination control system of an indoor air quality monitoring device according to claim 6, wherein, The first and second pressure taking ends of the double-cavity differential pressure sensor are respectively connected to the front cavity outside the filter screen and the rear cavity inside the filter screen through independent capillary guide tubes, the capillary guide tubes are routed along the inner wall of the shell and avoid the internal heat source and the optical path area of the optical alignment device, the processor collects the micro pressure difference signal at a frequency not less than five times per second and performs representative value extraction of the sliding median or percentile, the reference pressure difference ΔPref and the maximum allowed pressure difference ΔPmax and the window length for sampling and smoothing are stored in the memory and read by the processor during operation.

10. The sensor coordination control system of an indoor air quality monitoring device according to claim 6, wherein, The internal and external temperature sensors are respectively connected to the processor through independent buses, the power detection module is a shunt resistance sampling circuit or a power metering chip and is electrically connected to the analog-to-digital conversion unit of the processor, the processor is configured to calculate the equivalent thermal resistance according to the internal and external temperatures and the equivalent power and generate a parameter set for channel level temperature compensation and resource scheduling, and at the same time, the control priority order and corresponding threshold table of the display screen brightness, wireless transmission duty cycle and buzzer duty cycle are stored in the memory and the control signal output is performed in sequence and according to the threshold table when the state machine is running.

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