Sound monitoring equipment and ash removal method thereof

Abstract

The invention provides sound monitoring equipment and an ash removal method thereof, the sound monitoring equipment comprises a collection cavity, a sound collection assembly and an ash removal assembly, the sound collection assembly is deployed in the collection cavity, one side of the collection cavity is provided with a sound transmission hole, and the ash removal assembly is deployed in the collection cavity; the dust removal assembly is used for removing dust in the collection cavity. The dust cleaning assembly is used for cleaning the dust of the collection cavity, so that the sound transmission hole (and the peripheral dust cover) is prevented from being blocked by dust, the influence on the sound collection capability of the sensor is reduced, and the sound collection effect is improved.

Description

Technical Field

[0001] This invention relates to the field of monitoring, and more specifically, to a sound monitoring device and a method for cleaning the dust thereon. Background Technology

[0002] In recent years, with the widespread use of industrial monitoring sensors on large equipment, many industrial scenarios have placed higher demands on the dust prevention of sensors. Currently, industrial sound monitoring devices used in industrial scenarios do not have active dust removal devices. They are generally equipped with dust covers or dust films for physical dust protection, or the sound holes are designed to face downwards. If the dust film becomes clogged, there are no countermeasures (for dust removal).

[0003] When sound acquisition sensors are used in dusty environments, the dust cover or sound-transmitting holes of the sound acquisition sensors can easily become clogged with dust, which seriously affects the sound acquisition capability of the sensors. Therefore, the issue of dust removal is particularly important. Summary of the Invention

[0004] The purpose of this invention is to provide a sound monitoring device and a dust removal method thereof to improve the above-mentioned problems.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of the present invention are as follows: In a first aspect, embodiments of the present invention provide a sound monitoring device, the sound monitoring device comprising: a collection cavity, a sound collection component, and a dust removal component, the sound collection component being deployed in the collection cavity, a sound-transmitting hole being provided on one side of the collection cavity, and the dust removal component being deployed in the collection cavity; The dust removal component is used to remove dust from the collection chamber.

[0006] Optionally, a dust cover is installed on the side of the outside of the collection chamber near the sound-transmitting hole.

[0007] Optionally, the sound monitoring device further includes a control unit, which is connected to the dust removal assembly; The control unit is used to control the dust removal component to remove dust from the collection cavity when a dust removal command is triggered.

[0008] Optionally, when a dust removal command is triggered, the control unit is used to determine the current dust removal level based on the degree of dust accumulation, and control the dust removal component based on the current dust removal level.

[0009] Optionally, the control unit is also connected to the sound acquisition component; The control unit is used to acquire the on-site noise signal monitored by the sound acquisition component, decompose the on-site noise signal using the Fourier formula, divide the sinusoidal signal of each frequency band obtained by the decomposition according to the working frequency, harmonic frequency and bandwidth of the industrial equipment deployed in the industrial site, extract the background noise signal component, and then obtain the current background noise power. The control unit is used to determine the degree of dust accumulation on the noise side based on the current background noise power and the reference background noise power, wherein the reference background noise power is the background noise power obtained by collecting noise signals from the industrial site when the acquisition cavity is in a clean state.

[0010] Optionally, the control unit is used to obtain the background noise bandwidth corresponding to the background noise signal component, and determine the current background noise power based on the background noise bandwidth and the noise power spectral density.

[0011] Optionally, the sound monitoring device is further provided with two light-sensing test groups, the first light-sensing test group being exposed and deployed in the acquisition cavity, and the second light-sensing test group being sealed and deployed in the acquisition cavity; The photosensitive test group includes a first resistor, a second resistor, a light emitter, and a photosensitive receiver. One end of the first resistor and one end of the second resistor are connected to the power supply, the other end of the first resistor is connected to the positive terminal of the light-emitting element, the other end of the second resistor is connected to the positive terminal of the photosensitive receiving tube, and the negative terminals of the light-emitting element and the photosensitive receiving tube are grounded. The control unit is connected to the positive terminal of the photosensitive receiving tube in each of the two photosensitive test groups to obtain the voltage difference between them, and to determine the degree of dust accumulation on the photosensitive side based on the voltage difference.

[0012] Optionally, the dust removal component is a loudspeaker, and the control unit is used to output a drive signal with a preset frequency range to the loudspeaker to drive the loudspeaker to work; at the same time, it acquires the sound signal from the sound acquisition component and acquires the drive signal frequency at the maximum amplitude of the sound signal as the target frequency; The target frequency corresponds to the driving signal frequency of the highest gray level.

[0013] Secondly, embodiments of the present invention provide a method for cleaning dust from a sound monitoring device, applied to the aforementioned sound monitoring device, the method comprising: Determine whether to trigger the dust removal command; When the dust removal command is triggered, the dust removal component is controlled to remove dust from the collection chamber.

[0014] Optionally, determining whether to trigger a dust removal command includes: A cleaning command is triggered when the degree of dust accumulation in the acquisition cavity exceeds the cleaning trigger threshold. Alternatively, a dust cleaning command may be considered triggered upon receiving a dust cleaning command. Alternatively, a dust cleaning command may be triggered when the time interval since the last dust cleaning reaches the pre-cycle interval.

[0015] Compared to existing technologies, this invention provides a sound monitoring device and its cleaning method. The sound monitoring device includes a sound acquisition cavity, a sound acquisition component, and a cleaning component. The sound acquisition component is deployed within the sound acquisition cavity, and a sound-transmitting hole is provided on one side of the sound acquisition cavity. The cleaning component is used to remove dust from the sound acquisition cavity. By cleaning the sound acquisition cavity with the cleaning component, the sound-transmitting hole (and the surrounding dust cover) is prevented from being blocked by dust, reducing the impact on the sound acquisition capability of the sensor and improving the sound acquisition effect.

[0016] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A front view of a sound monitoring device provided in an embodiment of the present invention.

[0019] Figure 2 Left view of the sound monitoring device provided in an embodiment of the present invention.

[0020] Figure 3 A top view of the sound monitoring device provided in an embodiment of the present invention.

[0021] Figure 4 This is a circuit diagram for a light-sensing test provided in an embodiment of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0024] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0026] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed when in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0027] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0029] Please refer to Figure 1 , Figure 2 as well as Figure 3 . Figure 1 This is a front view of the sound monitoring device provided in an embodiment of the present invention. Figure 2 Left view of the sound monitoring device provided in an embodiment of the present invention. Figure 3 This is a top view of a sound monitoring device provided in an embodiment of the present invention. The sound monitoring device includes: a acquisition cavity, a sound acquisition component, and a dust removal component. The sound acquisition component may be, but is not limited to, a microphone or a sound sensor. In the figure, a microphone is used as the sound acquisition component, a speaker as the dust removal component, and a microphone bracket as a mounting bracket for illustrative purposes.

[0030] The sound acquisition component is deployed inside the acquisition cavity, and a sound-transmitting hole is provided on one side of the acquisition cavity. There can be one or more sound-transmitting holes, which are located in the sound acquisition direction of the sound acquisition component, such as the side facing the microphone. Apart from the sound-transmitting hole, the acquisition cavity has no other gaps or holes. The cavity is required to be designed to be airtight so that all airflow passes through the sound-transmitting hole to ensure the dust removal efficiency.

[0031] The dust removal component is deployed inside the acquisition chamber. The dust removal component can be a speaker, a piston blower mechanism driven by an external motor, or an organ box blower mechanism. Alternatively, the dust removal component can be an air pipe, with one end of the air pipe deployed inside the acquisition chamber and the other end connected to a blower.

[0032] In one alternative implementation, the acquisition chamber is divided into multiple sub-cavities by cadmium plates. Each sub-cavity houses one or more sound acquisition components to accommodate the installation of a microphone matrix. Each sub-cavity is equipped with a mounting bracket, on which the sound acquisition components are fixed. Multiple microphone sensors can be mounted on a single bracket, enabling the installation of multiple microphones or a microphone matrix.

[0033] The dust removal component is used to remove dust from the collection chamber.

[0034] In the sound monitoring device provided in this embodiment of the invention, the dust removal component cleans the acquisition cavity to prevent the sound transmission hole (and the surrounding dust cover) from being blocked by dust, thereby reducing the impact on the sound acquisition capability of the sensor and improving the sound acquisition effect.

[0035] Please continue to refer to this. Figure 3 A dust cover is installed on the side of the collection chamber near the sound transmission hole to further prevent dust from clogging it.

[0036] Optionally, a waterproof and breathable membrane may be provided on the side of the dust cover near the sound-permeable opening.

[0037] In one alternative implementation, the sound monitoring device further includes a control unit (not shown in the figure), which is connected to the dust removal assembly. The control unit can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), and a microprocessor (MCU); it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0038] The control unit is used to control the dust removal component to remove dust from the collection chamber when a dust removal command is triggered.

[0039] A cleaning command is triggered when the dust accumulation in the acquisition chamber exceeds the cleaning trigger threshold; or when a cleaning command is received; or when the time interval since the last cleaning reaches the pre-cycle interval.

[0040] In one alternative implementation, when a dust removal command is triggered, the control unit determines the current dust removal level based on the degree of dust accumulation and controls the dust removal components based on the current dust removal level.

[0041] It should be understood that the higher the degree of dust accumulation, the higher the dust removal level, for example, the higher the amplitude or frequency of the speaker diaphragm vibration, or the greater the output power of the blower mechanism.

[0042] Determining the cleaning level by the current level of dust accumulation and controlling the cleaning components accordingly can extend the lifespan of the cleaning components or reduce cleaning power consumption. For example, different cleaning vibration intensities can be matched to the level of dust accumulation. In areas with less dust, the cleaning amplitude of the speaker can be appropriately reduced to extend the speaker's lifespan.

[0043] Regarding how to accurately obtain the degree of dust accumulation in the collection cavity, this embodiment of the invention also provides an optional implementation method, please refer to the following.

[0044] The control unit is also connected to the sound acquisition component.

[0045] The control unit is used to acquire the on-site noise signal (the industrial site where the sound monitoring equipment is deployed) monitored by the sound acquisition component. It decomposes the on-site noise signal using the Fourier formula, and divides the sinusoidal signal of each frequency band according to the operating frequency, harmonics and bandwidth of the industrial equipment deployed in the industrial site. It then extracts the background noise signal component and obtains the current background noise power.

[0046] Alternatively, the sinusoidal patterns in each frequency band can be obtained by decomposing using the Fourier formula, as follows: v(t)=a1sin(ω't)+a2sin(2ω't)+...+aksin(kω't); Where, v(t): the time-varying amplitude of the sound wave (converted into a measurable electrical signal, unit: mV); t: time (unit: s); k: harmonic order, a positive integer (1,2,3,…,n); kω't: the instantaneous phase angle of the k-th harmonic (unit: rad); ak: the amplitude of the k-th sine component (converted into a measurable electrical signal, unit: mV).

[0047] The control unit is used to determine the degree of dust accumulation on the noise side based on the current background noise power and the reference background noise power. The reference background noise power is the background noise power obtained by collecting noise signals from the industrial site when the acquisition cavity is in a clean state.

[0048] The collection chamber being in a clean state can be understood as being dust-free, with the difference between the degree of dust accumulation and 0 being less than a set value, such as 0.1.

[0049] After Fourier expansion, the time-domain noise signal of each piece of industrial equipment corresponds to different frequency characteristic points (such as N-harmonic frequencies) on the frequency domain spectrum. Equipment faults can be inferred by monitoring equipment noise. Therefore, background noise monitoring is also within the monitoring range of industrial sound monitoring devices, but it only identifies the background noise characteristic values ​​and measures their noise power values.

[0050] The industrial sound monitoring device collects and stores background noise power values ​​when clean. As the device becomes increasingly dirty, blockage of the sound holes affects the collected background noise power values, causing them to gradually decrease. When the difference reaches a certain threshold, a dust removal alarm is triggered. Background noise is chosen to determine sound hole blockage because the background noise value is relatively stable and does not fluctuate excessively.

[0051] Optionally, the control unit is used to obtain the background noise bandwidth corresponding to the background noise signal component, and determine the current background noise power based on the background noise bandwidth and the noise power spectral density.

[0052] Noise power (dBm) is a measure of noise signal strength. There is a close relationship between noise power and noise power spectral density. Noise power spectral density refers to the noise power per unit frequency band, usually expressed in dBm / Hz, and the formula is as follows: Background noise power = noise power spectral density × bandwidth; This can be simplified to: PdBm = PdBm / Hz + 10 log10(BW Hz), where PdBm represents the background noise power, PdBm / Hz is the noise power spectral density, and BW Hz represents the background noise bandwidth.

[0053] Noise power spectral density describes the energy distribution of a noise signal at various frequencies. Different types of noise sources have different power density characteristics. The power density of background noise is uniformly distributed across the entire spectrum. Therefore, by calculating the noise power spectral density, the noise intensity at different frequencies can be determined.

[0054] In one alternative implementation, the sound monitoring device is further provided with two light-sensing test groups, the first light-sensing test group being deployed exposed inside the acquisition cavity, and the second light-sensing test group being deployed sealed inside the acquisition cavity.

[0055] Please refer to Figure 4 , Figure 4 This is a light-sensing test circuit diagram provided for an embodiment of the present invention. The light-sensing test group includes a first resistor (R1), a second resistor (R2), a light-emitting element (LED1) (which may be, but is not limited to, a light-emitting diode), and a photosensitive receiver (D1).

[0056] One end of the first resistor and one end of the second resistor are connected to the power supply (Ui). The two photosensitive test groups are connected to the same power supply. The other end of the first resistor is connected to the positive terminal of the light-emitting element, and the other end of the second resistor is connected to the positive terminal of the photosensitive receiver. The negative terminals of the light-emitting element and the negative terminal of the photosensitive receiver are grounded.

[0057] The control unit is connected to the positive terminal of the photosensitive receiver tube in each of the two photosensitive test groups (either directly to acquire voltage or indirectly through a voltage measuring device) to obtain the voltage difference between them, and to determine the degree of dust accumulation on the photosensitive side based on the voltage difference.

[0058] The voltage difference can be directly used as the degree of dust accumulation on the photosensitive side, or the degree of dust accumulation on the photosensitive side can be determined according to a pre-set mapping relationship.

[0059] In this embodiment of the invention, a second photosensitive test group is introduced as a reference control, which is sealed and deployed in the acquisition cavity. This can eliminate the influence of electrical property fluctuations in the photosensitive test circuit on the test results and ensure the accuracy of the obtained degree of dust accumulation on the photosensitive side.

[0060] In this embodiment of the invention, the degree of dust accumulation can be a combined value of the degree of dust accumulation on the noise side and the degree of dust accumulation on the light-sensing side, or the two can be not combined. The dust removal command can be triggered when the degree of dust accumulation on the noise side is greater than a first threshold and the degree of dust accumulation on the light-sensing side is greater than a second threshold, or when the degree of dust accumulation on the noise side is greater than the first threshold or the degree of dust accumulation on the light-sensing side is greater than the second threshold.

[0061] In one optional implementation, when the current background noise power is less than the reference background noise power and the difference between the two is greater than a set noise power deviation threshold, and / or when the voltage difference is greater than a set voltage deviation threshold, a dust removal command is triggered without performing a dust accumulation degree conversion, thereby reducing the amount of calculation.

[0062] Optionally, the formula for calculating the voltage difference is:

[0063] in, Indicates the voltage difference. Indicates the power supply voltage. This represents the equivalent resistance of the photosensitive receiver in the first photosensitive test group. This represents the equivalent resistance of the photosensitive receiver in the second photosensitive test group. This indicates the resistance value of the second resistor.

[0064] In an alternative implementation, a first photosensitive test group can also be set up, and the control unit is used to obtain the positive terminal voltage value of the photosensitive receiver tube in the first photosensitive test group to ground, and determine the degree of dust accumulation on the photosensitive side based on this.

[0065] Please continue to refer to this. Figure 1 In one optional embodiment, the dust removal assembly employs a loudspeaker, specifically a waterproof diaphragm loudspeaker. Optionally, the waterproof diaphragm loudspeaker is deployed within the acquisition cavity and positioned opposite the sound-transmitting hole (though not limited to this), with its diaphragm facing the sound-transmitting hole. After the waterproof diaphragm loudspeaker is installed in the cavity, it needs to be sealed. Subsequently, when driven, the diaphragm can drive the air inside the cavity to vibrate in order to achieve the dust removal effect. Therefore, this is the main component for dust removal.

[0066] The control unit is used to output a drive signal within a preset frequency range to the speaker to drive the speaker to work; at the same time, it acquires the sound signal from the sound acquisition component and uses the drive signal frequency at the maximum amplitude of the sound signal as the target frequency.

[0067] The preset frequency range can be (0.5). 0~1.5 0), 0 represents the resonant frequency of the speaker. The target frequency corresponds to the drive signal frequency of the highest gray level. In one optional implementation, the resonant frequency of the speaker can be directly used as the target frequency.

[0068] When the dust removal level is not the highest dust removal level, the drive signal frequency is adaptively offset relative to the target frequency.

[0069] ,in, 0 represents the resonant frequency of the speaker, L represents the inductance value of the speaker, and C represents the capacitance value of the speaker.

[0070] This invention also provides a method for cleaning dust from a sound monitoring device, which can be applied to, but is not limited to, the sound monitoring device described above. The method for cleaning dust from a sound monitoring device includes: S10, determine whether to trigger the dust cleaning command.

[0071] S20 controls the dust removal component to remove dust from the collection chamber when the dust removal command is triggered.

[0072] Optionally, S10 determines whether to trigger a dust removal command, including any one of S110, S120, and S130.

[0073] S110 triggers a cleaning command when the degree of dust accumulation in the acquisition cavity is higher than the dust removal trigger threshold.

[0074] S120 considers the dust cleaning command to be triggered when it receives the dust cleaning command.

[0075] S130, a dust cleaning command is triggered when the time interval since the last dust cleaning reaches the pre-cycle interval.

[0076] In summary, the present invention provides a sound monitoring device and its cleaning method. The sound monitoring device includes a sound acquisition cavity, a sound acquisition component, and a cleaning component. The sound acquisition component is deployed within the sound acquisition cavity, and a sound-transmitting hole is provided on one side of the sound acquisition cavity. The cleaning component is deployed within the sound acquisition cavity to remove dust from the sound acquisition cavity. By cleaning the sound acquisition cavity with the cleaning component, the sound-transmitting hole (and the surrounding dust cover) is prevented from being blocked by dust, reducing the impact on the sound acquisition capability of the sensor and improving the sound acquisition effect.

[0077] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0078] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A sound monitoring device, characterized in that, The sound monitoring device includes: a collection cavity, a sound collection component, and a dust removal component. The sound collection component is deployed in the collection cavity, and a sound-transmitting hole is provided on one side of the collection cavity. The dust removal component is deployed in the collection cavity. The dust removal component is used to remove dust from the collection chamber.

2. The sound monitoring device as described in claim 1, characterized in that, A dust cover is installed on the side of the outside of the collection chamber near the sound-transmitting hole.

3. The sound monitoring device as described in claim 1, characterized in that, The sound monitoring device also includes a control unit, which is connected to the dust removal assembly; The control unit is used to control the dust removal component to remove dust from the collection cavity when a dust removal command is triggered.

4. The sound monitoring device as described in claim 3, characterized in that, When a dust removal command is triggered, the control unit determines the current dust removal level based on the degree of dust accumulation and controls the dust removal component according to the current dust removal level.

5. The sound monitoring device as described in claim 3, characterized in that, The control unit is also connected to the sound acquisition component; The control unit is used to acquire the on-site noise signal monitored by the sound acquisition component, decompose the on-site noise signal using the Fourier formula, divide the sinusoidal signal of each frequency band obtained by the decomposition according to the working frequency, harmonic frequency and bandwidth of the industrial equipment deployed in the industrial site, extract the background noise signal component, and then obtain the current background noise power. The control unit is used to determine the degree of dust accumulation on the noise side based on the current background noise power and the reference background noise power, wherein the reference background noise power is the background noise power obtained by collecting noise signals from the industrial site when the acquisition cavity is in a clean state.

6. The sound monitoring device as described in claim 5, characterized in that, The control unit is used to obtain the background noise bandwidth corresponding to the background noise signal component, and to determine the current background noise power based on the background noise bandwidth and the noise power spectral density.

7. The sound monitoring device as described in claim 3, characterized in that, The sound monitoring device is also equipped with two light-sensing test groups. The first light-sensing test group is exposed and deployed in the acquisition cavity, while the second light-sensing test group is sealed and deployed in the acquisition cavity. The photosensitive test group includes a first resistor, a second resistor, a light emitter, and a photosensitive receiver. One end of the first resistor and one end of the second resistor are connected to the power supply, the other end of the first resistor is connected to the positive terminal of the light-emitting element, the other end of the second resistor is connected to the positive terminal of the photosensitive receiving tube, and the negative terminals of the light-emitting element and the photosensitive receiving tube are grounded. The control unit is connected to the positive terminal of the photosensitive receiving tube in each of the two photosensitive test groups to obtain the voltage difference between them, and to determine the degree of dust accumulation on the photosensitive side based on the voltage difference.

8. The sound monitoring device as described in claim 3, characterized in that, The dust removal component uses a loudspeaker, and the control unit is used to output a drive signal with a preset frequency range to the loudspeaker to drive the loudspeaker to work; at the same time, it acquires the sound signal from the sound acquisition component and acquires the drive signal frequency at the maximum amplitude of the sound signal as the target frequency; The target frequency corresponds to the driving signal frequency of the highest gray level.

9. A method for cleaning dust from a sound monitoring device, characterized in that, The method, applied to the sound monitoring device according to any one of claims 1-8, comprises: Determine whether to trigger the dust removal command; When the dust removal command is triggered, the dust removal component is controlled to remove dust from the collection chamber.

10. The method for cleaning dust from the sound monitoring device as described in claim 9, characterized in that, The process of determining whether to trigger a dust removal command includes: A cleaning command is triggered when the degree of dust accumulation in the acquisition cavity exceeds the cleaning trigger threshold. Alternatively, a dust cleaning command may be considered triggered upon receiving a dust cleaning command. Alternatively, a dust cleaning command may be triggered when the time interval since the last dust cleaning reaches the pre-cycle interval.

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