Sound collecting device and range hood

Abstract

The present application relates to a kind of sound acquisition device and range hood, sound acquisition device includes sound acquisition element, also include shell, the sound acquisition element is located in the shell, the shell is defined on the sound propagation channel and the second sound inlet for sound into the sound propagation channel, the shell is also provided with anti-vortex structure for inhibiting vortex shedding or making vortex shedding position away from the second sound inlet in the position adjacent to second sound inlet. Advantage is that: both oil-proof and windproof purposes can be achieved, and noise signals can be fully collected, thereby ensuring the accuracy of sound acquisition.

Description

Technical Field

[0001] This invention relates to the field of range hood technology, and in particular to a sound acquisition device and a range hood. Background Technology

[0002] A range hood is a kitchen appliance used to purify the kitchen environment. Noise from range hoods has always been a major problem for users. Active noise cancellation, as a new noise reduction technology, is being considered for application in range hoods. Active noise cancellation devices typically include a microphone and a speaker. The microphone collects the noise generated when the range hood is operating, and the collected noise sound waves are transmitted to the controller as electrical signals. The controller analyzes and processes the signals and sends instructions to the speaker to emit sound waves that match the noise sound waves, thus neutralizing the noise and achieving a noise reduction effect. For example, Chinese invention patent application CN202010935185.0 (publication number CN111928310A) discloses such a range hood with active noise cancellation. In this range hood, the microphone is located inside the casing and arranged in an array around the fan, while the speaker assembly is located below the fan. For example, similar disclosures have been made in the application for "Rainbow Hood and Active Noise Reduction Device" with application number CN202221822214.3 and the application for "Low Noise Range Hood" with application number CN202222650354.3.

[0003] To ensure noise reduction effectiveness, microphones and speakers used in existing active noise cancellation systems are often placed inside the air duct of the range hood. However, due to the oily environment of the range hood, the microphones and speakers are often contaminated, which leads to a decrease in noise reduction effectiveness or even malfunction of the active noise cancellation system as it is used for a longer period of time. To address this, Chinese utility model patent application CN201820250745.7 discloses an active noise reduction device for a range hood with an oil-proof device, comprising an input device, a central data processor, and a noise reduction unit. The input device includes a microphone, which is arbitrarily installed at any location on the range hood. The noise reduction unit includes at least two noise reduction boxes, which are located at the bottom of the range hood's volute, directly facing the air inlet. An oil-proof device is located below the noise reduction box, also located at the bottom of the volute and covering the noise reduction box. The oil-proof device includes a porous sound-permeable shell and an oil-proof and sound-permeable film attached to the surface of the porous sound-permeable shell. At least one noise-reducing speaker is installed inside the noise reduction box. Both the microphone and the noise-reducing speaker are connected to the central data processor. The central data processor loads a noise reduction device self-test module and an oil stain detection module. The oil stain detection module detects the oil stain damage to the oil-proof device. The self-test module receives and processes the system signals reported by the device to determine whether there is an increase in the microphone and noise-reducing speaker. The self-test module also includes a timed detection module.

[0004] However, the oil-proof device of the active noise reduction device in the aforementioned patent application still has certain shortcomings. This oil-proof device achieves sound transmission and oil prevention through a porous sound-permeable shell and an oil-proof film attached to the surface of the porous sound-permeable shell. It does not take into account the influence of wind noise in the air duct of the range hood, that is, it does not carry out effective wind noise prevention treatment. On the other hand, if the porous sound-permeable shell has a large number of openings, it will have an adverse effect on oil and wind prevention. If the number of openings is small, the noise will be lost more during the propagation process, which will reduce the accuracy of sound acquisition. Therefore, how to provide a sound acquisition device that can effectively prevent oil and wind, thereby ensuring the accuracy of sound acquisition, has become a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0005] The first technical problem to be solved by the present invention is to provide a sound acquisition device that can achieve both oil and wind protection, and also ensure that noise signals are fully acquired, thereby guaranteeing the accuracy of sound acquisition, in light of the current state of the technology.

[0006] The second technical problem to be solved by the present invention is to provide a range hood that applies the above-mentioned sound acquisition device, in view of the current state of the prior art.

[0007] The technical solution adopted by this invention to solve the first technical problem is as follows:

[0008] A sound acquisition device includes a sound acquisition element and a housing. The sound acquisition element is disposed inside the housing. The housing defines a sound propagation channel and a second sound inlet for sound to enter the sound propagation channel. The housing is also provided with an anti-vortex structure near the second sound inlet to suppress vortex shedding or to move the vortex shedding position away from the second sound inlet.

[0009] Since the sound acquisition element is installed inside the housing, it can effectively isolate the airflow in the duct from interfering with the sound acquisition element and prevent oil contamination in the airflow from polluting the sound acquisition element. The anti-vortex structure set at the second sound inlet of the housing can suppress the fall of airflow vortices or make the fall of airflow vortices as far away from the second sound inlet as possible, thereby effectively reducing the impact of fall vortex pressure pulsation on microphone noise acquisition.

[0010] As an improvement, the sound propagation channel includes a first channel segment and a second channel segment that are connected sequentially and arranged at an angle. The sound acquisition element is located in the first channel segment, and the second sound inlet is located at the port of the second channel segment away from the first channel segment.

[0011] The first and second channel sections are arranged at an angle, making the entire path of noise in the duct from the second sound inlet into the second channel section, and then propagating to the location of the sound acquisition element in the first channel section a turning path. This turning path avoids excessive oil contamination directly passing through the sound propagation channel and coming into contact with the sound acquisition element. Instead, most of the oil contamination adheres to the side wall or windproof sound-permeable parts of the second channel section, thus keeping the sound acquisition element as far away from oil contamination as possible and extending its service life. On the other hand, considering that the target noise (mainly from the fan system) to be acquired by the active noise cancellation system is low-frequency noise, the sound propagation path in the sound acquisition device adopts a turning path design. This design weakens high-frequency sounds (such as the high-frequency sound components in wind noise and high-frequency sound components generated by the fan system, etc., which are not the target noise) while having little impact on low-frequency sounds. Therefore, it is well-suited for low-frequency noise propagation within the sound acquisition device, facilitating accurate acquisition by the sound acquisition element. The main reason is that low-frequency noise has a longer wavelength, which better adapts to the bends and irregular shapes of the duct. When low-frequency noise propagates in a curved pipe, its longer wavelength makes it less susceptible to obstruction and reflection, allowing it to propagate and diffuse more effectively. High-frequency noise, on the other hand, has a shorter wavelength and is easily reflected and absorbed by the shape and curves of the pipe, making it more difficult for it to propagate and diffuse within the pipe compared to low-frequency noise.

[0012] As an improvement, the aforementioned sound acquisition device is installed in the duct of the fume extraction device, the second channel section is arranged along the extension direction of the duct, and the second sound inlet is formed at the leeward end of the housing, the opening direction of the second sound inlet is consistent with the extension direction of the duct.

[0013] The aforementioned "one end of the housing facing away from the wind" can be understood as: one end of the housing adjacent to the fan system of the range hood along the extension direction of the air duct.

[0014] The above-mentioned "the second channel section is arranged along the extension direction of the air duct" can be understood as the overall extension direction of the second channel section being consistent with or parallel to the extension direction of the air duct, or it can be understood as the overall extension direction of the second channel section having a slight tilt angle (such as a tilt angle of 0-30°) relative to the extension direction of the air duct.

[0015] Considering that the noise in the duct (mainly from the fan system) propagates along the duct's extension direction and in the opposite direction to the airflow within the duct, the second sound inlet is located on the leeward side of the casing, with its opening direction aligned with the duct's extension direction. This allows the second sound inlet to face the sound source, enabling it to directly receive the noise within the duct. It also avoids the second sound inlet being directly impacted by airflow, reducing the adverse effects of wind noise on the accuracy of sound acquisition.

[0016] Generally speaking, in order to minimize the contamination of the sound acquisition element in the first channel segment by oil, the orientation of the first sound inlet should avoid being consistent with the extension direction of the second channel segment. That is, the opening direction of the first sound inlet and the extension direction of the second channel segment should preferably be set at an angle. However, the angle formed between the orientation of the first sound inlet and the extension direction of the second channel segment also needs to be reasonably designed. If the angle formed between the orientation of the first sound inlet and the extension direction of the second channel segment is too small, oil will still enter the first channel segment through the first sound inlet and contaminate the sound acquisition element. If the angle formed between the orientation of the first sound inlet and the extension direction of the second channel segment is too large, the sound propagation path will turn too much, which will have an adverse effect on the sound propagation, that is, a part of the sound pressure will be lost, which is not conducive to the accurate acquisition of noise by the sound acquisition element. Therefore, preferably, the first channel segment has a first sound inlet that communicates with the second channel segment, and the extension line of the opening direction of the first sound inlet is perpendicular to the extension direction of the second channel segment.

[0017] The housing can be a one-piece structure, such as a one-piece bent tube structure. However, for the convenience of installing components such as the sound acquisition element, the housing is preferably a split structure designed to be assembled together using fasteners. Specifically, the housing includes a mounting frame and a windproof cover. The front side wall of the mounting frame has a receiving groove. The sound acquisition element is placed in the receiving groove, which constitutes the first channel segment. The front opening of the receiving groove is the first sound inlet. The windproof cover covers the mounting frame and defines a sound acquisition channel that communicates with the first sound inlet of the receiving groove and is located on the front side of the receiving groove. This sound acquisition channel constitutes the second channel segment.

[0018] In the aforementioned phrase "the sound acquisition channel is located on the front side of the receiving tank," "front side" should not be limited to the actual front-to-back direction of the range hood or duct. Instead, it should be understood as the sound acquisition channel being located closer to the internal center of the duct than the receiving tank. For example, when the protective device in this invention is installed on the left side wall of the duct, "the sound acquisition channel is located on the front side of the receiving tank" should be understood as the sound acquisition channel being located on the right side of the receiving tank, i.e., closer to the internal center of the duct. Having the sound acquisition channel on the front side of the receiving tank ensures that the entire path of noise from the duct, from the second sound inlet into the sound acquisition channel, and then propagating to the location of the sound acquisition element in the receiving tank, is a turning path. This turning path prevents excessive grease from directly passing through the sound acquisition channel and contacting the sound acquisition element. Instead, most of the grease adheres to the side wall of the sound acquisition channel or the windproof and sound-permeable parts, thus keeping the sound acquisition element as far away from grease as possible and extending its service life.

[0019] To further improve windproof performance, a windproof and sound-permeable component is also provided in the sound acquisition channel, which shields the front side of the first sound inlet. This component effectively eliminates wind noise; even if a small amount of airflow enters the sound acquisition channel, pressure pulsations are weakened within the component, thus reducing the impact on the accuracy of the microphone's sound acquisition.

[0020] To reduce the impact of vortex shedding at the end of the windshield on the accuracy of sound acquisition, a feasible approach is to employ a scheme to suppress vortex shedding. Specifically, the edge of the leeward end of the windshield is designed with a serrated or wavy structure, which constitutes the anti-vortex structure of the windshield. By adding a serrated or wavy structure to the end of the windshield to manage the airflow, vortex generation can be effectively reduced, thus lowering the impact of vortex pulsation pressure on the accuracy of sound acquisition by the sound acquisition element.

[0021] To reduce the impact of vortex shedding at the end of the windshield on the accuracy of sound acquisition, a feasible approach is to position the vortex shedding point as far away from the second sound inlet as possible. Specifically, the leeward end of the windshield and the mounting bracket define the second sound inlet, and an extension wall extending along the opening direction of the second sound inlet is provided at this inlet. At least a section of this extension wall adjacent to the second sound inlet is constructed to gradually slope inward along the airflow direction. This inwardly sloping portion of the extension wall constitutes the anti-vortex structure of the windshield. The outwardly expanding and inwardly sloping edge of the windshield also deflects the vortex shedding generated at the end into the airflow channel, increasing the distance between the airflow vortex and the second sound inlet, thereby effectively reducing the impact of vortex pressure pulsation on microphone noise acquisition.

[0022] To reduce the impact of detachment vortices formed at the end of the windshield on the accuracy of sound acquisition, another feasible solution is to provide a guide wall at the leeward end of the windshield, which gradually slopes towards the side of the mounting bracket along the airflow direction within the air duct. This guide wall constitutes the anti-vortex structure of the windshield. The presence of this guide wall at the end of the windshield creates a guide slope that slopes towards the sidewall of the air duct. This slope prevents airflow separation caused by sudden changes in the flow channel, eliminating detachment vortices and thus preventing vortex pulsation pressure from affecting the accuracy of microphone sound acquisition.

[0023] Considering that the extension wall of the windproof cover tilting towards the side wall of the air duct would adversely affect the amount of sound entering the second sound inlet, auxiliary sound-permeable holes are also distributed on the guide wall, and each of the auxiliary sound-permeable holes together constitutes the second sound inlet.

[0024] Considering that the air duct of a range hood is mostly set vertically, in order to adapt to this, both the sound acquisition channel and the air duct are set vertically, and the opening direction of the second sound inlet is upward.

[0025] The technical solution adopted by the present invention to solve the second technical problem is: a range hood, including a duct for the passage of smoke and a sound acquisition device disposed in the duct, wherein the sound acquisition device adopts the above-mentioned sound acquisition device.

[0026] As an improvement, the sound acquisition element is a microphone.

[0027] Compared with the prior art, the advantages of the present invention are as follows: Since the sound acquisition element is installed inside the housing, it can effectively isolate the airflow in the air duct from interfering with the sound acquisition element and prevent oil contamination of the sound acquisition element in the airflow. The anti-vortex structure set at the second sound inlet of the housing can suppress the fall of airflow vortices or make the fall of airflow vortices as far away from the second sound inlet as possible, thereby effectively reducing the impact of fall vortex pressure pulsation on microphone noise acquisition. Attached Figure Description

[0028] Figure 1 This is a three-dimensional structural diagram of the protective device according to Embodiment 1 of the present invention;

[0029] Figure 2 This is an exploded view of the protective device according to Embodiment 1 of the present invention;

[0030] Figure 3 This is a vertical sectional view of the protective device according to Embodiment 1 of the present invention;

[0031] Figure 4 for Figure 3 A structural diagram omitting the thickness of the windproof and sound-permeable components;

[0032] Figure 5 For along Figure 3 A sectional view cut along the AA direction;

[0033] Figure 6 This is a three-dimensional structural diagram of the protective device of Embodiment 1 of the present invention installed in the air duct;

[0034] Figure 7 for Figure 6 A transverse sectional view cut along the front-to-back direction;

[0035] Figure 8 A schematic diagram of the sound propagation process at the first sound inlet of the mounting bracket;

[0036] Figure 9 This is a vertical sectional view of the protective device according to Embodiment 2 of the present invention;

[0037] Figure 10 This is a front view of the protective device according to Embodiment 2 of the present invention;

[0038] Figure 11 This is a vertical sectional view of the protective device according to Embodiment 3 of the present invention;

[0039] Figure 12 This is a front view of the protective device according to Embodiment 3 of the present invention;

[0040] Figure 13 This is a vertical sectional view of the protective device according to Embodiment 4 of the present invention;

[0041] Figure 14 This is a front view of the protective device according to Embodiment 4 of the present invention. Detailed Implementation

[0042] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0043] The specification and claims of this invention use terms indicating direction, such as "front," "rear," "upper," "lower," "left," "right," "side," "top," and "bottom," to describe various exemplary structural parts and elements of the invention. However, these terms are used herein merely for ease of explanation and are determined based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in this invention can be arranged in different orientations, these terms indicating direction are for illustrative purposes only and should not be considered as limitations. For example, "upper" and "lower" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

[0044] Example 1

[0045] Figures 1-7 A preferred embodiment of the sound acquisition device and range hood of the present invention is shown.

[0046] The sound acquisition device includes a sound acquisition element 11 and a housing 2. A sound propagation channel is defined within the housing 2, comprising a first channel segment and a second channel segment arranged sequentially at an angle. The sound acquisition element 11 is located in the first channel segment. The first channel segment has a first sound inlet 211 communicating with the second channel segment, and the second channel segment has a second sound inlet 45 for external sound to enter. The extension line of the opening direction of the first sound inlet 211 intersects the extension line of the opening direction of the second sound inlet 45. In a preferred embodiment, both the first and second channel segments are straight channels, wherein the extension lines of the first and second channel segments intersect.

[0047] Active noise reduction systems are typically installed in the duct 10 of kitchen appliances such as range hoods or integrated cooktops with fume extraction functions. A sound acquisition device, a crucial component of the active noise reduction system, is also installed within the duct 10 of the range hood. Taking a range hood as an example, the "duct" can refer to the range hood's casing or a box structure with a dedicated channel for fumes, such as the channel between the fan system and the fume hood's smoke collection hood in a ceiling-mounted range hood. Active noise reduction systems generally include a sound acquisition element 11 (microphone) and a speaker. The microphone collects the noise generated by the range hood during operation, and the collected noise waves are transmitted to the controller as electrical signals. The controller analyzes and processes the signals and sends a command to the speaker to emit sound waves that match the noise waves, thus neutralizing the noise and achieving noise reduction. In this embodiment, the sound acquisition device can be used to install the sound acquisition element 11 and provide protection against oil and wind.

[0048] The sound acquisition device is located below the fan system, meaning that the noise generated by the fan system propagates downwards along the air duct 10, and the sound acquisition device is positioned precisely along the downward propagation path within the air duct 10. In addition to the housing, the sound acquisition device includes an oil-proof and sound-permeable membrane 28 and a windproof and sound-permeable component 30. The housing includes a mounting bracket 20 and a windproof cover 40.

[0049] This embodiment uses a housing 1 with a separate "channel" for the passage of cooking fumes as an example to illustrate the installation structure of the sound acquisition device. The channel inside the housing 1 serves as the air duct 10. The mounting bracket 20 can be installed on the rear side wall of the air duct 10, and it has a receiving groove 21 for placing the sound acquisition element 11. This receiving groove constitutes the first channel section of the housing 2. The front of the receiving groove 21 has an opening as a first sound inlet 211 for sound to enter the receiving groove 21. This first sound inlet 211 should be understood as an opening that allows external (in this embodiment, the sound acquisition channel) sound to enter the receiving groove 21 and be effectively acquired by the sound acquisition element. Figure 8 The openings defined by the boundary points A1, A2, etc. of the receiving groove 21 in the circumferential direction do not necessarily refer to the maximum opening at the front of the receiving groove 21. When the mounting bracket 20 is installed on the rear side wall of the air duct 10, the rear wall of the part of the mounting bracket 20 containing the receiving groove 21 is in contact with the rear side wall of the air duct 10.

[0050] The mounting bracket 20 also has a third mounting portion 263 extending to the left and right sides respectively, protruding beyond the wind shield 40, and a fourth mounting portion 264 extending downward at the bottom of the mounting bracket 20, protruding beyond the wind shield 40. Both the third mounting portion 263 and the fourth mounting portion 264 are connected to the side wall of the air duct 10 by screws. The lower part of the receiving groove 21 of the mounting bracket 20 has a forward-extending connecting post 265, and the wind shield 40 can be connected to the connecting post 265 of the mounting bracket 20 by screws 50.

[0051] The wind shield 40 includes a first sidewall 411 and a second sidewall 412 arranged opposite to each other and spaced apart, and a third sidewall 413 connecting the front edge of the first sidewall 411 and the front edge of the second sidewall 412, thereby forming a rear-opening shield structure. The third sidewall 413 of the wind shield 40 is located in front of the receiving groove 21 of the mounting bracket 20. The third sidewall 413 of the wind shield 40 has a shape along the airflow direction within the air duct 10 (e.g., ...). Figure 3The guide surface 4130 (in the direction indicated by the hollow arrow) gradually slopes towards the inside of the air duct 10. Specifically, the guide surface 4130 is located at the lower part of the third side wall 413, that is, at the windward end of the third side wall 413. It slopes forward from bottom to top, while the upper part of the third side wall 413 is basically vertically extended and is opposite to the portion of the receiving groove 21 of the mounting bracket 20 in the front-back direction. Along the airflow direction inside the air duct 10, the guide surface 4130 of the wind shield 40 is located upstream of the receiving groove 21 of the mounting bracket 20. Arranging the guide surface 4130 of the wind shield 40 lower also ensures that there is sufficient space inside the wind shield 40, opposite to the front of the receiving groove 21, to arrange components such as the windproof sound-permeable component 30 and the oil-proof sound-permeable membrane 28. Furthermore, considering that the excessively large inclination angle of the guide surface 4130 towards the inside of the air duct 10 will also affect the airflow within the air duct 10 to some extent, such as affecting the air volume or generating additional noise, the inclination angle of the guide surface 4130 of the wind shield 40 needs to be reasonably designed. The included angle between the guide surface 4130 of the wind shield 40 and the side wall of the air duct 10 used to install the wind shield 40 is denoted as A, and the value of A is in the range of: A≤60°. In order to reduce the impact of the installation of the protective device on the flow field inside the air duct 10, the dimension of the air duct 10 in the front-back direction in this embodiment is denoted as a, and the distance by which the wind shield 40 protrudes forward relative to the side wall of the air duct 10 used to install the wind shield 40 is denoted as b. Considering that if the forward protrusion of the wind shield 40 is too large, such as b / a > 0.35, it will affect the airflow within the duct 10 and cause turbulence at the location of the protective device within the duct 10, generating additional noise and affecting the accuracy of sound acquisition. Therefore, the value of b / a needs to be reasonably limited. In this embodiment, preferably, b / a ≤ 0.35, see details. Figure 7 .

[0052] To improve the oil-proof effect, the windproof cover 40 in this embodiment can be made of plastic or metal.

[0053] In this embodiment, the windproof cover 40 and the front side of the mounting bracket 20 form a vertically extending gap channel in the front-rear direction. The upper end of this gap channel (i.e., the end closer to the noise source) is open, and the lower end (i.e., the end away from the noise source) is closed, which is the sound acquisition channel 200. The sound acquisition channel 200 is located on the front side of the mounting bracket 20, thus forming the second channel segment of the aforementioned housing 2. The extension direction of the sound acquisition channel 200 is consistent with the extension direction of the air duct 10. More specifically, a second sound inlet 45, which communicates with the aforementioned sound acquisition channel 200, is defined between the leeward end of the windproof cover 40 (i.e., the section near the fan system of the range hood along the extension direction of the air duct) and the front side wall of the mounting bracket 20. The air duct 10 in this embodiment also extends vertically, that is, the extension direction of the sound acquisition channel 200 is consistent with the extension direction B2 of the air duct 10. The opening direction B1 of the first sound inlet 211 intersects with the extension direction B3 of the sound acquisition channel 200 to form a first included angle M. Considering that if the first included angle M formed between the orientation B1 of the first sound inlet 211 and the extension direction B3 of the sound acquisition channel 200 is too small, oil will still enter the receiving tank 21 through the first sound inlet 211 and contaminate the sound acquisition element 11. If the first included angle M formed between the orientation B1 of the first sound inlet 211 and the extension direction B3 of the sound acquisition channel 200 is too large, the sound propagation path will turn too much, which will have an adverse effect on the sound propagation, that is, a part of the sound pressure will be lost, which is not conducive to the accurate acquisition of noise by the sound acquisition element. Therefore, the first included angle M formed between the orientation of the first sound inlet 211 and the extension direction B3 of the sound acquisition channel 200 also needs to be reasonably designed. Preferably, the value of the first included angle M in this embodiment is 90°, that is, the opening direction B1 of the first sound inlet 211 is perpendicular to the extension direction B3 of the sound acquisition channel 200.

[0054] The lower section of the sound acquisition channel 200 is opposite to the first sound inlet 211 at the front of the receiving groove 21 of the mounting bracket 20 in the front-back direction. The wind shield 40 effectively prevents high-speed oil fume airflow from directly impacting the windproof sound-permeable component 30, greatly reducing the pollution of the windproof sound-permeable component 30 by oil fumes. Simultaneously, after the wind shield 40 and mounting bracket 20 are combined, only the upper second sound inlet 45 is retained, directly isolating the lower airflow noise and secondary turbulence noise interference, so that the noise entering the windproof sound-permeable component 30 mainly comes from above, i.e., the direction of the main noise source of the range hood, thus ensuring the accuracy of noise acquisition. In a preferred embodiment, to improve the protective effect of the wind shield 40 on the windproof sound-permeable component 30 and minimize the contact between the windproof sound-permeable component 30 and the fumes in the air duct, an extension wall 46 extends upwards from the upper edge of the wind shield 40 relative to the top surface of the windproof sound-permeable component 30; that is, the top edge of the extension wall 46 is higher than the top surface of the windproof sound-permeable component 30. Due to the airflow within the duct 10, an airflow vortex will form at the leeward end of the wind shield 40 (i.e., at the second sound inlet 45), which will generate noticeable wind noise. The extension wall 46 of the wind shield 40 can keep the airflow vortex as far away from the second sound inlet 45 as possible, thus preventing the airflow vortex from affecting the target noise to be collected entering from the second sound inlet 45.

[0055] Since the sound acquisition element 11 is installed in the receiving slot 21 of the mounting bracket 20 and a windproof cover 40 is provided outside the mounting bracket 20, the interference of the airflow in the air duct 10 to the sound acquisition element 11 can be effectively isolated, and the oil in the airflow can be prevented from contaminating the sound acquisition element 11. At the same time, a windproof sound-permeable component 30 is provided in the sound acquisition channel formed between the mounting bracket 20 and the windproof cover 40, which can effectively reduce the impact of wind noise. Even if a small amount of airflow enters the sound acquisition channel 200, the pressure pulsation can be weakened in the windproof sound-permeable component 30, thereby reducing the impact on the accuracy of microphone sound acquisition. Furthermore, considering that the noise in the duct 10 (mainly from the fan system) propagates along the extension direction of the duct 10 and in the opposite direction to the airflow direction within the duct 10, arranging the sound acquisition channel 200 along the extension direction of the duct allows the second sound inlet 45 of the sound acquisition channel 200 to face the sound source so that the noise can be directly received. Also, considering the need for a sufficiently long windproof and sound-permeable component 30 along the sound propagation path to reduce wind noise and decrease the impact of airflow in the duct 10 on sound acquisition, this embodiment arranges the sound acquisition channel 200, which houses the windproof and sound-permeable component 30, along the extension direction of the duct 10. This allows the entire protective device to be smaller in size perpendicular to the duct extension direction, meaning it occupies less space in the duct 10 of the range hood. Consequently, the wind resistance at the location of the protective device within the duct 10 is reduced, thus not affecting the stability of the airflow within the duct 10 and simultaneously reducing wind noise to a certain extent. Based on this, considering that the duct environment of the range hood is full of oil, if the opening direction B1 of the first sound inlet 211 is consistent with the extension direction B3 of the sound collection channel 200, the sound collection element 11 is easily contaminated by the oil flowing down the duct 10. Therefore, in this embodiment, the opening direction B1 of the first sound inlet 211 of the receiving groove 21 is set at a certain angle with the extension direction B3 of the sound collection channel 200. This makes the entire sound propagation path of the noise in the duct 10 from the second sound inlet 45 into the sound collection channel 200 and then propagating to the location of the sound collection element 11 in the receiving groove 21 a turning path. This turning path can prevent too much oil from directly passing through the sound collection channel 200 and contacting the sound collection element 11. Instead, most of the oil adheres to the side wall of the sound collection channel 200 or the windproof and sound-permeable part 30, thereby keeping the sound collection element 11 as far away from the oil as possible and extending the service life of the sound collection element 11.Furthermore, considering that the target noise (mainly from the fan system) to be collected by the active noise reduction system is low-frequency noise, the sound propagation path within the protective device adopts a turning path design. This weakens high-frequency sounds (such as the high-frequency sound components in wind noise and non-target noise such as high-frequency sound components generated by the fan system) while having a smaller impact on low-frequency sounds. Therefore, it is well-suited for the propagation of low-frequency noise within the protective device, facilitating accurate collection by the sound acquisition element 11. The main reason is that low-frequency noise has a longer wavelength, making it better suited to the bends and irregular shapes of pipes. When low-frequency noise propagates in a curved pipe, its longer wavelength makes it less susceptible to obstruction and reflection, thus allowing for better propagation and diffusion. High-frequency noise, on the other hand, has a shorter wavelength and is easily reflected and absorbed by the shape and bends of the pipe, making it more difficult for it to propagate and diffuse within the pipe compared to low-frequency noise.

[0056] An oil-resistant and sound-permeable membrane 28 covers the first sound inlet 211 of the receiving groove 21 of the mounting frame 20. The windproof and sound-permeable component 30 is a uniformly thick layered structure, positioned within the sound acquisition channel 200, specifically at the edge of the front opening of the receiving groove 21 of the mounting frame 20, and covering the oil-resistant and sound-permeable membrane 28. More specifically, to facilitate installation of the oil-resistant and sound-permeable membrane 28 and ensure its sealing after installation, the receiving groove 21 also forms an annular stepped portion 210 at the edge of its first sound inlet 211, and the oil-resistant and sound-permeable membrane 28 is disposed on this annular stepped portion 210. To ensure the oil-resistant performance of the oil-resistant and sound-permeable membrane 28 while effectively transmitting sound waves, the oil-resistant and sound-permeable membrane 28 in this embodiment is preferably a polyethylene film. Wherein, as Figure 3 As shown, there is a fourth distance, denoted as f, between the oil-proof sound-permeable membrane 28 and the sound acquisition element 11. The value of f is in the range of f ≥ 2 mm. This avoids contact between the membrane and the sound acquisition element 11 due to membrane vibration or micro-deformation, which could lead to variations in sound propagation and affect the accuracy of sound acquisition. The windproof sound-permeable component 30 does not directly contact the oil-proof sound-permeable membrane 28 to ensure the oil-proof effect. Specifically, there is a sixth distance, denoted as n, between the oil-proof sound-permeable membrane 28 and the main body of the windproof sound-permeable component 30 in the front-back direction.

[0057] To effectively mitigate airflow and eliminate airflow impact, the windproof sound-permeable component 30 is made of porous sound-absorbing material, such as polyurethane foam or melamine foam, with a porosity greater than 70%. In this embodiment, the windproof sound-permeable component 30 not only prevents airflow from impacting the oil-proof sound-permeable membrane 28 and generating additional noise, but also, due to its porous material properties, absorbs high-frequency components of sound energy, achieving a filtering function for noise signals. More specifically, the front sidewall of the windproof sound-permeable component 30 is fitted against the rear sidewall of the third sidewall 413 of the windproof cover 40, thus placing the windproof sound-permeable component 30 in a compressed state. This compression increases the material density, effectively reducing the possibility of airflow pressure pulsation penetration, thereby further improving the windproof effect.

[0058] The windproof and sound-permeable component 30 of this embodiment includes an extension section 301 extending upward from the top edge of the first sound inlet 211 of the receiving groove 21, and the length of the extension section 301 of the windproof and sound-permeable component 30 is denoted as h, and the dimension of the first sound inlet 211 of the receiving groove 21 in the vertical direction is m, wherein the value range of h / m is: 0.125≤h / m≤0.6. Since the sound acquisition channel 200 has a vertically extending section and a horizontally extending section, that is, there is a turning part at the first sound inlet 211 of the receiving groove 21, if the extension length of the outer peripheral edge of the windproof sound-permeable component 30 relative to the edge of the first sound inlet 211 of the receiving groove 21 is too short (e.g., h / m is less than 0.125), it will also be greatly affected by wind noise. After the above parameter design, the windproof effect of the windproof sound-permeable component is effectively guaranteed, and the accuracy of sound acquisition is avoided due to the excessively short extension length of the outer peripheral edge of the windproof sound-permeable component. Of course, considering the adverse effect of the windproof sound-permeable component 30 on sound attenuation, the length of the extension section 301 of the windproof sound-permeable component 30 should not be too large. If h / m is greater than 0.6, it will cause the sound to not effectively meet the sound pressure requirements of the sound acquisition element 11 when it propagates to the receiving groove 21, thus reducing the accuracy of noise acquisition.

[0059] To prevent the windproof sound-permeable component 30 from contacting the continuously flowing oil on the side wall of the air duct 10, a first gap, denoted as d, is maintained between the windproof sound-permeable component 30 and the rear side wall of the air duct 10 after installation on the mounting bracket 20. The value of d is ≥ 4mm. Similarly, to ensure windproof performance, the front-to-back dimension (thickness) of the main body of the windproof sound-permeable component 30 is denoted as e, where the value of e is ≥ 3mm (40mm ≥ e ≥ 3mm). Specifically, when e ≥ 3mm, the windproof sound-permeable component 30 effectively prevents the airflow in the air duct from directly impacting the sound-collecting element 11. However, considering the adverse effect of the windproof ball 30 (generally made of a porous material that prevents airflow disturbance and is sound-permeable) on sound attenuation, the front-to-back dimension (thickness) of the windproof sound-permeable component 30 cannot be too large, requiring e ≤ 40mm. Meanwhile, given a fixed front-to-back dimension (i.e., thickness) of the windproof sound-permeable component 30, the left-to-right dimension d1 of the main body of the windproof sound-permeable component 30 must also be adapted accordingly. That is, e / d1 needs to be reasonably limited. Specifically, if e / d1 is too small (e.g., e / d1 < 0.2), it means that the main body of the windproof sound-permeable component 30 is larger in the left-to-right direction, increasing the area of ​​its upper part in contact with oil stains, which will directly affect the service life of the windproof sound-permeable component 30. If e / d1 is too large (e.g., e / d1 > 0.5), it means that the main body of the windproof sound-permeable component 30 is smaller in the left-to-right direction, which is not conducive to the transmission of sound from a larger angle range in the upper horizontal direction into the sound acquisition channel 200, affecting the accuracy of sound acquisition.

[0060] Due to the windproof and sound-permeable element 30 in the sound acquisition channel 200, there will be some loss in the propagation path of sound from the second sound inlet 45 to the location of the sound acquisition element 11, that is, a portion of the sound pressure will be lost. Therefore, it is necessary to ensure that a sufficient amount of noise to be acquired enters the receiving slot 21 of the mounting bracket 20 so that it can be received by the sound acquisition element 11 and achieve the purpose of accurately acquiring the noise signal. Specifically, the principle of sound attenuation and compensation is as follows:

[0061] L w =L1-ΔL+10lgS0

[0062] Among them, the noise energy that the sound acquisition component can collect per unit time is the sound power L. w ;

[0063] The sound pressure level is L1 when sound is transmitted to the top surface of the windproof and sound-permeable component 30.

[0064] Due to the weakening effect of the windproof and sound-permeable component 30, the noise pressure loss is ΔL;

[0065] The area S0 of the cross-section at the second sound inlet 45 of the sound acquisition channel 200;

[0066] Therefore, if the sound attenuation is severe due to the excessive thickness or length of the windproof and sound-permeable component 30 along the sound propagation path, the sound power L collected by the sound acquisition element can be ensured by increasing S0. w The size will not decrease, thus ensuring the accuracy of sound acquisition. Specifically, the ratio between the cross-sectional area S0 of the second sound inlet 45 of the sound acquisition channel 200 and the opening area S of the first sound inlet 211 at the front of the receiving groove 210 needs to be reasonably limited, wherein S0 / S≥0.18. This ensures that sufficient noise can pass through the sound acquisition channel 200 of the protective device to compensate for the sound pressure loss due to the setting of the windproof sound-permeable element 30, thereby ensuring that the sound pressure requirement of the sound acquisition element 11 can be met when the sound propagates to the second sound inlet 45, further improving the accuracy of noise acquisition.

[0067] On the other hand, in this embodiment, the vertical dimension of the main body of the windproof and sound-permeable component 30 is denoted as g. To match the size of the first sound inlet 211 at the front of the receiving groove and to ensure the windproof effect, 100mm ≥ g ≥ 10mm. The cross-sectional area of ​​the main body of the windproof and sound-permeable component 30 near the second sound inlet 45 is S1. Wherein, g / 2 + e / 2 represents the propagation path length of sound in the windproof and sound-permeable component. When the propagation path is longer, the sound loss is greater, according to the principle of sound propagation L... w =L1+10lgS(L W (where L is the sound power, L1 is the sound pressure, and S is the area at the sound inlet) It can be seen that the sound pressure decreases during sound propagation due to sound loss. As compensation, S1 should be increased to ensure that enough sound is collected by the sound acquisition element. Therefore, considering sound propagation loss and compensation, the value of S1 / (g / 2+e / 2) should be greater than 8mm, and the preferred value range is 10mm to 15mm. If S1 / (g / 2+e / 2) is too small, such as S1 / (g / 2+e / 2)≤8, it means that the entrance area of ​​the windproof sound-permeable part at the end position near the second sound inlet is small, and the amount of sound entering is insufficient to balance the adverse effects of the windproof sound-permeable part 30 on sound loss in the vertical and horizontal directions and the front and back directions, which reduces the accuracy of the sound acquisition element 11. If S1 / (g / 2+e / 2) is too large, such as S1 / (g / 2+e / 2)≥15, it means that the entrance area of ​​the windproof sound-permeable component 30 at the end position near the second sound inlet 45 is large enough to allow sound to be effectively transmitted from top to bottom. Similarly, the area of ​​the upper part of the windproof sound-permeable component 30 in contact with oil stains increases, which affects the service life of the windproof sound-permeable component 30.

[0068] In this embodiment, since the windproof sound-permeable component 30 is filled in the sound acquisition channel 200, that is, there is no gap between the front side of the windproof sound-permeable component 30 and the windproof cover 40, the cross-sectional area S1 of the main body of the windproof sound-permeable component 30 near the second sound inlet 45 is basically the same as the cross-sectional area S0 of the second sound inlet 45 of the sound acquisition channel 200.

[0069] In this embodiment, after the sound acquisition element 11 is installed in the receiving slot 21 of the mounting frame 20, an oil-proof sound-permeable membrane 28 is set at its first sound inlet 211, and a windproof sound-permeable component 30 is set outside it. A windproof cover 40 is then set outside the windproof sound-permeable component 30. This protective device, employing the above three layers of protection, can effectively eliminate wind noise and prevent oil contamination. After the windproof cover 40 covers the windproof sound-permeable component 30, a second sound inlet 45 is reserved at the leeward end to communicate with the outside. According to the airflow pattern, the flow near the second sound inlet 45 of the windproof sound-permeable component 30 is a low-speed, high-static-pressure region. The presence of this low-speed, high-static-pressure region reduces wind noise, thereby ensuring that the target noise to be collected (i.e., the noise of the fan system) can be effectively transmitted to the receiving slot 21 of the mounting frame 20 through the second sound inlet 45, ensuring the accuracy of noise data acquisition. On the other hand, considering the impact of the windproof sound-permeable component 30 and the windproof cover 40 on the obstruction and loss of sound propagation, limiting the ratio of the opening area S at the first sound inlet of the receiving groove 21 to the opening area S0 at the second sound inlet 45 of the sound acquisition channel 200 within a reasonable range can ensure that enough noise passes through the protective device and is received by the sound acquisition element, further improving the accuracy of noise acquisition.

[0070] This embodiment also relates to a range hood, including a duct 10 through which smoke passes and an active noise reduction system disposed in the duct 10. The active noise reduction system includes a sound acquisition element 11 for collecting sound signals. The sound acquisition element 11 is a microphone. The microphone is disposed in the receiving slot 21 of the mounting bracket 20 of the aforementioned protective device and then installed on the side wall of the duct 10 through the protective device.

[0071] Example 2

[0072] Figures 9-10 Another preferred embodiment of the sound acquisition device and range hood of the present invention is shown. The difference between this embodiment and Embodiment 1 is that the end edge of the extension wall 46 of the wind shield 40 is configured as a serrated or wavy structure 460. By adding a serrated or wavy structure 460 to the end of the extension wall 46 of the wind shield 40 to manage the airflow, the generation of vortices at the second air inlet 45 can be effectively reduced, thus reducing the impact of vortex pulsation pressure on the accuracy of sound acquisition by the sound acquisition element 11.

[0073] Example 3

[0074] Figures 11-12 Another preferred embodiment of the sound acquisition device and range hood of the present invention is shown. The difference between this embodiment and Embodiment 1 is that the section of the extension wall 46 of the wind shield 40 near its end edge is constructed with a structure that gradually slopes inward towards the airflow direction within the air duct 10. Expanding the end edge of the extension wall 46 of the wind shield 40 outward, i.e., tilting it towards the airflow direction within the air duct 10, deflects the separation vortex generated at the end of the airflow towards the airflow direction within the air duct 10, causing the airflow vortex to deviate as far as possible from the second sound inlet 45, thereby effectively reducing the impact of separation vortex pressure pulsation on microphone noise acquisition.

[0075] Example 4

[0076] Figures 13-14 Another preferred embodiment of the sound acquisition device and range hood of the present invention is shown. The difference between this embodiment and Embodiment 1 is that the section of the extension wall 46 of the wind shield 40 near its end edge (i.e., the guide wall 46a) is constructed to gradually slope towards the side where the mounting bracket 20 is located along the airflow direction within the air duct 10, that is, towards the side wall of the air duct 10 used to fix the mounting bracket 20. The end of the extension wall 46 of the wind shield 40 can either be in close contact with the side wall 100 of the air duct 10, or it can be close to the side wall 100 of the air duct 10 without contacting it. The guide wall 46a of the extension wall 46 forms a guide slope for guiding the airflow towards the side wall of the air duct 10. This guide slope can prevent airflow separation caused by large abrupt changes in the flow channel, eliminate separation vortices, and thereby reduce the impact of vortex pulsation pressure on the accuracy of microphone sound acquisition. Considering that the inclination of the extension wall 46 of the wind shield 40 toward the side wall near the air duct 10 would adversely affect the amount of sound entering the second sound inlet 45, an auxiliary sound-transmitting hole 461 is also provided on the extension wall 46 to meet the sound volume requirements entering the sound acquisition channel 200.

Claims

1. A sound acquisition device, comprising a sound acquisition element (11), characterized in that: It also includes a housing (2), the sound acquisition element (11) is disposed inside the housing (2), the housing (2) defines a sound propagation channel and a second sound inlet (45) for sound to enter the sound propagation channel, and the housing (2) is also provided with an anti-vortex structure near the second sound inlet (45) for suppressing vortex shedding or making the vortex shedding position away from the second sound inlet (45); The sound propagation channel includes a first channel segment and a second channel segment that are connected in sequence and arranged at an angle. The sound acquisition element (11) is located in the first channel segment, and the second sound inlet (45) is located at the port of the second channel segment away from the first channel segment. The aforementioned sound acquisition device is installed in the air duct (10) of the fume extraction device. The second channel section is arranged along the extension direction of the air duct (10), and the second sound inlet (45) is formed at the leeward end of the housing (2). The opening direction (B4) of the second sound inlet (45) is consistent with the extension direction of the air duct (10). The housing (2) includes a mounting bracket (20) and a windproof cover (40). A receiving groove (21) is provided on the front side wall of the mounting bracket (20). The sound acquisition element (11) is placed in the receiving groove (21). The receiving groove (21) constitutes the first channel segment. The windproof cover (40) covers the mounting bracket (20) and defines a sound acquisition channel (200) located in front of the receiving groove (21) between the windproof cover (40) and the mounting bracket (20). The sound acquisition channel (200) constitutes the second channel segment. The edge portion of the leeward end of the windproof cover (40) is configured with a sawtooth or wave-shaped structure (460), which constitutes the anti-vortex structure of the windproof cover (40).

2. The sound acquisition device according to claim 1, characterized in that: The first channel segment has a first sound inlet (211) that communicates with the second channel segment, and the extension line of the opening direction of the first sound inlet (211) is perpendicular to the extension direction of the second channel segment.

3. The sound acquisition device according to claim 2, characterized in that: The front opening of the receiving groove (21) is the first sound inlet (211) that communicates with the second channel section.

4. The sound acquisition device according to claim 3, characterized in that: The sound acquisition channel (200) is also provided with a windproof and sound-permeable component (30), which is shielded in front of the first sound inlet (211).

5. The sound acquisition device according to claim 1 or 2, characterized in that: The second channel section and the air duct (10) both extend vertically, and the opening direction of the second sound inlet (45) is upward.

6. A sound acquisition device, comprising a sound acquisition element (11), characterized in that: It also includes a housing (2), the sound acquisition element (11) is disposed inside the housing (2), the housing (2) defines a sound propagation channel and a second sound inlet (45) for sound to enter the sound propagation channel, and the housing (2) is also provided with an anti-vortex structure near the second sound inlet (45) for suppressing vortex shedding or making the vortex shedding position away from the second sound inlet (45); The sound propagation channel includes a first channel segment and a second channel segment that are connected in sequence and arranged at an angle. The sound acquisition element (11) is located in the first channel segment, and the second sound inlet (45) is located at the port of the second channel segment away from the first channel segment. The aforementioned sound acquisition device is installed in the air duct (10) of the fume extraction device. The second channel section is arranged along the extension direction of the air duct (10), and the second sound inlet (45) is formed at the leeward end of the housing (2). The opening direction (B4) of the second sound inlet (45) is consistent with the extension direction of the air duct (10). The housing (2) includes a mounting bracket (20) and a windproof cover (40). A receiving groove (21) is provided on the front side wall of the mounting bracket (20). The sound acquisition element (11) is placed in the receiving groove (21). The receiving groove (21) constitutes the first channel segment. The windproof cover (40) covers the mounting bracket (20) and defines a sound acquisition channel (200) located in front of the receiving groove (21) between the windproof cover (40) and the mounting bracket (20). The sound acquisition channel (200) constitutes the second channel segment. The leeward end of the windproof cover (40) and the mounting bracket (20) define the second sound inlet (45), and an extension wall (46) extending along the opening direction of the second sound inlet (45) is provided at the second sound inlet (45). At least one section of the extension wall (46) adjacent to the second sound inlet (45) is constructed to gradually slope into the air duct (10) along the airflow direction. The part of the extension wall (46) that slopes into the air duct (10) also constitutes the anti-vortex structure of the windproof cover (40).

7. The sound acquisition device according to claim 6, characterized in that: The first channel segment has a first sound inlet (211) that communicates with the second channel segment, and the extension line of the opening direction of the first sound inlet (211) is perpendicular to the extension direction of the second channel segment.

8. The sound acquisition device according to claim 7, characterized in that: The front opening of the receiving groove (21) is the first sound inlet (211) that communicates with the second channel section.

9. The sound acquisition device according to claim 8, characterized in that: The sound acquisition channel (200) is also provided with a windproof and sound-permeable component (30), which is shielded in front of the first sound inlet (211).

10. The sound acquisition device according to claim 6 or 7, characterized in that: The second channel section and the air duct (10) both extend vertically, and the opening direction of the second sound inlet (45) is upward.

11. A sound acquisition device, comprising a sound acquisition element (11), characterized in that: It also includes a housing (2), the sound acquisition element (11) is disposed inside the housing (2), the housing (2) defines a sound propagation channel and a second sound inlet (45) for sound to enter the sound propagation channel, and the housing (2) is also provided with an anti-vortex structure near the second sound inlet (45) for suppressing vortex shedding or making the vortex shedding position away from the second sound inlet (45); The sound propagation channel includes a first channel segment and a second channel segment that are connected in sequence and arranged at an angle. The sound acquisition element (11) is located in the first channel segment, and the second sound inlet (45) is located at the port of the second channel segment away from the first channel segment. The aforementioned sound acquisition device is installed in the air duct (10) of the fume extraction device. The second channel section is arranged along the extension direction of the air duct (10), and the second sound inlet (45) is formed at the leeward end of the housing (2). The opening direction (B4) of the second sound inlet (45) is consistent with the extension direction of the air duct (10). The housing (2) includes a mounting bracket (20) and a windproof cover (40). A receiving groove (21) is provided on the front side wall of the mounting bracket (20). The sound acquisition element (11) is placed in the receiving groove (21). The receiving groove (21) constitutes the first channel segment. The windproof cover (40) covers the mounting bracket (20) and defines a sound acquisition channel (200) located in front of the receiving groove (21) between the windproof cover (40) and the mounting bracket (20). The sound acquisition channel (200) constitutes the second channel segment. The windproof cover (40) is also provided with a guide wall (46a) that extends gradually towards the side of the mounting frame (20) along the airflow direction in the air duct (10). The guide wall (46a) constitutes the anti-vortex structure of the windproof cover (40).

12. The sound acquisition device according to claim 11, characterized in that: The first channel segment has a first sound inlet (211) that communicates with the second channel segment, and the extension line of the opening direction of the first sound inlet (211) is perpendicular to the extension direction of the second channel segment.

13. The sound acquisition device according to claim 12, characterized in that: The front opening of the receiving groove (21) is the first sound inlet (211) that communicates with the second channel section.

14. The sound acquisition device according to claim 13, characterized in that: The sound acquisition channel (200) is also provided with a windproof and sound-permeable component (30), which is shielded in front of the first sound inlet (211).

15. The sound acquisition device according to claim 11 or 12, characterized in that: The second channel section and the air duct (10) both extend vertically, and the opening direction of the second sound inlet (45) is upward.

16. The sound acquisition device according to claim 11, characterized in that: The guide wall (46a) is also provided with auxiliary sound-permeable holes (461), and each of the auxiliary sound-permeable holes (461) together constitutes the second sound inlet (45).

17. A range hood, comprising a duct (10) through which smoke passes and a sound collection device disposed in the duct (10), characterized in that: The sound acquisition device described herein is the sound acquisition device according to any one of claims 1 to 16.

18. The range hood according to claim 17, characterized in that: The sound acquisition element (11) is a microphone.

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