Sound acquisition device and range hood

Abstract

The utility model relates to a sound acquisition device and range hood, sound acquisition device is provided in the air duct of the range hood, including shell and be provided the sound acquisition element in the shell, on the shell is limited the sound propagation channel, the sound propagation channel includes the second channel section that is arranged along the extension direction of air duct, and the second channel section is located in the second channel section. A second sound inlet which is communicated with the second channel section and is used for allowing sound in the air channel to enter the second channel section is formed in the leeward end of the shell, the opening direction of the second sound inlet is consistent with the extending direction of the air channel, and the second sound inlet is further provided with an oil-proof sound transmission part. The oil-proof and wind-proof sound collector has the advantages that the oil-proof and wind-proof purposes can be achieved, noise signals can be fully collected, and then the accuracy of sound collection is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of range hoods, in particular to a sound collection device and a range hood. Background Art

[0002] A range hood is a kitchen appliance for purifying the kitchen environment. The noise of the range hood has always been one of the main problems troubling users. As a new noise reduction technology, active noise reduction is also considered to be applied to range hoods for noise reduction. The active noise reduction device usually includes a microphone and a speaker, that is, the microphone collects the noise generated when the range hood is working, and the collected noise sound wave is transmitted to the controller in the form of an electrical signal. After being analyzed and processed by the controller, an instruction is sent to the speaker to control the speaker to emit a sound wave matching the noise sound wave to neutralize the noise sound wave, so as to achieve the noise reduction effect. For example, the Chinese invention patent application with the application number CN202010935185.0 (the application publication number is: CN111928310A) discloses such a range hood with an active noise reduction function. The microphone of this range hood is arranged inside the housing and surrounds the blower in an array distribution manner, and the speaker assembly is distributed below the blower. Another example is the "Range Hood and Its Active Noise Reduction Device" with the application number CN202221822214.3 and the "Low-Noise Range Hood" with the application number CN202222650354.3, which also have similar disclosures.

[0003] In order to ensure the noise reduction effect, the microphones and speakers used in the existing active noise reduction systems are often arranged inside the air duct of the range hood. However, due to the oil and grease environment of the range hood, the microphones and speakers are often contaminated, resulting in a reduction in the noise reduction effect of the active noise reduction system over time and even failures. For this reason, the Chinese utility model patent application with the application number CN201820250745.7 discloses an active noise reduction device for a range hood with an oil-proof device, including an input device, a central data processor and a noise reduction unit. The input device includes a microphone, and the microphone is arbitrarily installed at a place on the range hood. The noise reduction unit includes at least two noise reduction boxes, and the noise reduction boxes are arranged at the bottom of the range hood volute, facing the air inlet. An oil-proof device is arranged below the noise reduction box, and the oil-proof device is also arranged at the bottom of the volute and covers the noise reduction box. The oil-proof device includes a porous sound-permeable shell and an oil-proof sound-permeable film attached to the surface of the porous sound-permeable shell. At least one noise reduction speaker is arranged inside the noise reduction box. The microphone and the noise reduction speaker are both connected to the central data processor. The central data processor loads a self-check module and an oil pollution detection module for the noise reduction device. The oil pollution detection module detects the oil pollution and damage condition of the oil-proof device, and the self-check module receives and processes the self-system signals reported by the device to determine whether there is an increase in the microphone and the noise reduction speaker. At the same time, a timing detection module is arranged inside the self-check module.

[0004] However, the oil-proof device of the active noise reduction device of the above patent application still has certain shortcomings. The oil-proof device realizes 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, and does not take into account the influence of wind noise in the air duct of the range hood, that is, no effective wind noise prevention treatment is performed. On the other hand, if the number of openings of the above-mentioned porous sound-permeable shell is large, 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, resulting in the accuracy of sound collection being affected. Therefore, how to provide a sound collection device that can effectively prevent oil and achieve the purpose of wind prevention, thereby ensuring the accuracy of sound collection has become a technical problem that needs to be urgently solved by technical personnel in this field. Utility Model Content

[0005] The technical problem to be solved by the utility model is to provide a sound collection device which can achieve the purpose of oil and wind protection and can fully collect noise signals, thereby ensuring the accuracy of sound collection, in view of the current status of the prior art.

[0006] The second technical problem to be solved by the utility model is to provide a range hood using the above-mentioned sound collection device in view of the current status of the prior art.

[0007] The technical solution adopted by the utility model to solve the first technical problem is:

[0008] A sound collecting device is arranged in the air duct of a range fumes extraction device, comprising a shell and a sound collecting element arranged in the shell, the shell defines a sound propagation channel, the sound propagation channel comprises a second channel section arranged along the extension direction of the air duct, the shell is formed with a second sound inlet at the leeward end thereof, which is connected with the second channel section and allows the sound in the air duct to enter the second channel section, the opening direction of the second sound inlet is consistent with the extension direction of the air duct, and the second sound inlet is also provided with an oil-proof sound-permeable member.

[0009] The above-mentioned "end of the shell on the leeward side" can be understood as: along the extension direction of the air duct, one end of the shell adjacent to the fan system of the range hood. Considering that the noise in the air duct (mainly from the fan system) is propagated along the extension direction of the air duct, and the propagation direction is opposite to the flow direction of the airflow in the air duct, therefore, on the basis of arranging the second channel section along the extension direction of the air duct, the second sound inlet is arranged on the leeward side of the shell, and the opening direction is consistent with the extension direction of the air duct, so that the second sound inlet can be directed towards the sound source so as to directly receive the noise in the air duct, and also avoid the second sound inlet being directly impacted by the airflow, thereby reducing the adverse effect of wind noise on the accuracy of sound collection.

[0010] The above "the second channel section is arranged along the extending direction of the air duct" can be understood as that the overall extending direction of the second channel section is consistent with or parallel to the extending direction of the air duct, or that the overall extending direction of the second channel section has a certain inclination angle relative to the extending direction of the air duct (such as an inclination angle of 0 - 30°).

[0011] The sound collection element is arranged inside the housing, which can effectively isolate the interference of the air flow in the air duct to the sound collection element and prevent the oil stain in the air flow from contaminating the sound collection element. Arranging the second channel section of the housing along the extending direction of the air duct and designing the opening direction of the second sound inlet to be consistent with the extending direction of the air duct can facilitate the sound collection element to directly receive the noise in the air duct. Considering that a sufficient length of the channel path needs to be set on the sound propagation path for wind noise prevention to reduce the influence of the air flow in the air duct on sound collection, arranging the second channel section in the extending direction of the air duct can make the size of the whole sound collection device in the direction perpendicular to the extending direction of the air duct smaller, that is, it occupies less space in the air duct of the range hood, and then makes the air resistance at the position where the sound collection device is located in the air duct smaller, so it will not affect the stability of the air flow in the air duct, and at the same time, it also reduces the generation of wind noise to a certain extent. Setting an oil-proof sound transmission member at the second sound inlet can, on the one hand, prevent the oil stain from entering the sound propagation channel and further increase the oil-proof effect, and on the other hand, it can also play a role in wind noise prevention, reducing the transmission of the pressure pulse formed by the sudden change of the air flow at the second sound inlet into the sound propagation channel and improving the adverse influence on the accuracy of sound collection.

[0012] As an improvement, the sound propagation channel further includes a first channel section that is connected to the second channel section and arranged at an angle, and the sound collection element is arranged in the first channel section.

[0013] The first channel segment and the second channel segment are arranged at an angle, which makes the entire path of the noise in the air duct from the second sound inlet into the second channel segment and then to the position of the sound collection element in the first channel segment a turning path. This turning path can prevent excessive oil stains from directly passing through the sound propagation channel and contacting the sound collection element. Instead, most of the oil stains adhere to the side wall of the second channel segment or the windproof sound-permeable member, thereby enabling the sound collection element to be as far away from the oil stains as possible and extending the service life of the sound collection element. On the other hand, considering that the target noise (mainly from the fan system) that the active noise reduction system needs to collect is low-frequency noise, the turning path design is adopted for the sound propagation path in the sound collection device. It has a weakening effect on high-frequency sounds (such as the high-frequency sound components in wind noise and the high-frequency sound components generated by the fan system, etc., which are non-target noises), and has little impact on low-frequency sounds. Therefore, it can be better applied to the propagation of low-frequency noise in the sound collection device, which is conducive to the accurate collection of low-frequency noise by the sound collection element. The main reason is that the wavelength of low-frequency noise is longer, and it can better adapt to the bending and irregular shapes of the pipeline. When low-frequency noise propagates in a bent pipeline, due to its longer wavelength, it is not easily blocked and reflected by the pipeline, so it can better propagate and spread. While the wavelength of high-frequency noise is shorter, it is easily reflected and absorbed by the shape and bending of the pipeline, so it is more difficult to propagate and spread in the pipeline than low-frequency noise.

[0014] Generally speaking, in order to minimize the contamination of the sound collection element in the first channel segment by oil stains as much as possible, the orientation of the first sound inlet should be avoided to be the same as 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 be preferably 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. For example, if the angle formed between the orientation of the first sound inlet and the extension direction of the second channel segment is too small, the oil liquid will still enter the first channel segment through the first sound inlet and contaminate the sound collection 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 turning of the sound propagation path is too large, which will have an adverse impact on sound propagation, that is, a part of the sound pressure will be lost, which is not conducive to the accurate collection of noise by the sound collection element. Therefore, preferably, the first channel segment has a first sound inlet communicating 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.

[0015] The housing can be designed with an integral structure, such as a bent pipe structure with an integral design. However, for the convenience of installing components such as the sound collection element, the housing preferably adopts a split structure design assembled with fasteners. Specifically, the housing includes a mounting frame and a windproof cover. A receiving groove is formed on the front side wall of the mounting frame, and the sound collection element is placed in the receiving groove. The receiving groove constitutes the first channel section, and the front opening of the receiving groove is the first sound inlet. The windproof cover covers outside the mounting frame and defines a sound collection channel between the windproof cover and the mounting frame that is connected to the first sound inlet of the receiving groove and is located in front of the receiving groove. This sound collection channel constitutes the second channel section.

[0016] In the above-mentioned "the sound collection channel is located in front of the receiving groove", the "front side" should not be limited to the actual front and back directions of the range hood or the air duct, but should be understood as: the position where the sound collection channel is located is closer to the inner center position of the air duct relative to the position where the receiving groove is located. For example, when the protection device in the present invention is installed on the left side wall of the air duct, at this time, "the sound collection channel is located in front of the receiving groove" should be understood as: the sound collection channel is located on the right side of the receiving groove, that is, the side closer to the inner center position of the air duct. The sound collection channel being located in front of the receiving groove can make the entire path of the noise in the air duct entering the sound collection channel from the second sound inlet and then propagating to the position of the sound collection element in the receiving groove a turning path. This turning path can prevent too much oil stain from directly passing through the sound collection channel and contacting the sound collection element, but make most of the oil stain adhere to the side wall of the sound collection channel or the windproof and sound-transmitting member, thereby enabling the sound collection element to be as far away from the oil stain as possible and extending the service life of the sound collection element.

[0017] In a preferred solution, the oil-proof and sound-transmitting member is a second oil-proof and sound-transmitting film covering the second sound inlet. The setting of the second oil-proof and sound-transmitting film can play a role in isolating the oil stain and prevent the oil stain from entering the interior of the sound collection channel and contaminating the sound collection element.

[0018] In order to enable the oil liquid dripping onto the surface of the second oil-proof and sound-transmitting film to slide off in time under the action of its gravity and avoid having an adverse impact on the sound side transmission due to long-term attachment to the surface of the second oil-proof and sound-transmitting film, the opening direction of the second sound inlet is upward, and the second oil-proof and sound-transmitting film is inclined downward from front to back.

[0019] In order to install the second oil-proof and sound-transmitting film and arrange it in an inclined manner, the top of the mounting frame is lower than the top of the windproof cover. The front side of the second oil-proof and sound-transmitting film is connected to the rear side wall of the windproof cover, and the rear side of the second oil-proof and sound-transmitting film is connected to the top of the mounting frame.

[0020] Another preferred solution is that the oil-proof sound-permeable member is an oil-blocking and sound-permeable plate covering the second sound inlet, and sound-permeable holes are distributed on the oil-blocking and sound-permeable plate.

[0021] To prevent oil stains from entering the sound collection channel through the sound-permeable holes, an annular blocking edge extending upward is provided along the periphery of each of the sound-permeable holes on the oil-blocking and sound-permeable plate.

[0022] To enable the oil liquid dripping onto the surface of the oil-blocking and sound-permeable plate to slide off in time under the action of its gravity, the opening direction of the second sound inlet is upward, and the oil-blocking and sound-permeable plate slopes downward from front to back.

[0023] Generally speaking, the oil-blocking and sound-permeable plate can be a separate component independent of the wind shield or the mounting bracket, or can be integrally designed with the wind shield or the mounting bracket. To reduce the number of components of the sound collection device, the oil-blocking and sound-permeable plate is integrally designed with the wind shield or the mounting bracket.

[0024] To further improve the windproof effect, a windproof and sound-permeable member is further provided in the sound collection channel. The setting of the windproof and sound-permeable member can effectively eliminate wind noise. Even if a small amount of air flow enters the sound collection channel, the pressure pulsation can be weakened in the windproof and sound-permeable member, thereby reducing the impact on the sound collection accuracy of the microphone.

[0025] As an improvement, a receiving groove is formed on the front side wall of the mounting bracket, the sound collection element is arranged in the receiving groove, a first sound inlet for the sound in the sound collection channel to enter the receiving groove is provided at the front part of the receiving groove, the sound collection channel is located at the front side of the receiving groove, and the extending direction of the sound collection channel is perpendicular to the opening direction of the first sound inlet. The second sound inlet is defined between the windward end of the wind shield and the mounting bracket.

[0026] The above-mentioned "windward end of the wind shield" can be understood as: along the extending direction of the air duct, the end of the wind shield adjacent to the fan system of the range hood.

[0027] The opening direction of the first sound inlet of the accommodation groove is perpendicular to the extending direction in the sound collection channel. This makes the whole path for the noise in the air duct to enter the sound collection channel from the second sound inlet and then propagate to the position of the sound collection element in the accommodation groove a turning path. This turning path can prevent excessive oil stains from directly passing through the sound collection channel and contacting the sound collection element. Instead, most of the oil stains adhere to the side wall of the sound collection channel or the windproof sound-transmitting member, so that the sound collection element can be as far away from the oil stains as possible, extending the service life of the sound collection element. On the other hand, considering that the target noise (mainly from the fan system) that the active noise reduction system needs to collect is low-frequency noise, the design of the turning path for the sound propagation path in the sound collection device has a weakening effect on high-frequency sounds (such as the high-frequency sound components in wind noise and the high-frequency sound components generated by the fan system, etc., which are non-target noises), and has little impact on low-frequency sounds. Therefore, it can be better applied to the propagation of low-frequency noise in the sound collection device, which is conducive to the accurate collection of the sound collection element. The main reason is that the wavelength of low-frequency noise is longer, and it can better adapt to the bending and irregular shapes of the pipeline. When low-frequency noise propagates in a bent pipeline, due to its longer wavelength, it is not easily blocked and reflected by the pipeline, so it can better propagate and spread. While the wavelength of high-frequency noise is shorter, it is easily reflected and absorbed by the shape and bending of the pipeline, so it is more difficult to propagate and spread in the pipeline than low-frequency noise.

[0028] In order to further reduce the possibility of the sound collection element being contaminated by oil stains, a first oil-proof sound-transmitting membrane is also provided at the first sound inlet.

[0029] The technical solution adopted by the present invention to solve the second technical problem is: an oil fume extractor, including an air duct for the flue gas to pass through and a sound collection device arranged in the air duct, and the sound collection device adopts the above-mentioned sound collection device.

[0030] As an improvement, the sound collection element is a microphone.

[0031] Compared with the prior art, the advantages of the present utility model are as follows: By arranging the sound collection element inside the housing, it can effectively isolate the interference of the airflow in the air duct on the sound collection element and prevent the oil stain in the airflow from contaminating the sound collection element. The second channel section of the housing is arranged along the extension direction of the air duct, and the opening direction of the second sound inlet is designed to be the same as the extension direction of the air duct, which can facilitate the sound collection element to directly receive the noise in the air duct. Considering that a sufficient length of the channel path needs to be set on the sound propagation path to prevent wind noise and reduce the influence of the air duct airflow on sound collection, arranging the second channel section in the extension direction of the air duct can make the size of the entire sound collection device in the direction perpendicular to the extension direction of the air duct smaller, that is, it occupies less space in the air duct of the range hood, and thus the wind resistance at the position where the sound collection device is located in the air duct is smaller, so it will not affect the stability of the airflow in the air duct and at the same time can also reduce the generation of wind noise to a certain extent. By setting an oil-proof sound transmission member at the second sound inlet, on the one hand, it can prevent oil stains from entering the sound propagation channel, further increasing the oil-proof effect, and on the other hand, it can also play a role in preventing wind noise, reducing the transmission of the pressure pulse formed by the sudden change of the airflow at the second sound inlet into the sound propagation channel, and improving the adverse influence on the accuracy of sound collection. In the preferred solution, the sound propagation channel includes a first channel section and a second channel section arranged at an angle. Thus, the entire path of the noise in the air duct entering the second channel section from the second sound inlet and then propagating to the position of the sound collection element in the first channel section is a turning path. This turning path can prevent too much oil stain from directly passing through the sound propagation channel and contacting the sound collection element, but make most of the oil stains adhere to the side wall of the sound propagation channel, so that the sound collection element can be as far away from the oil stain as possible, extending the service life of the sound collection element. On the other hand, the sound propagation path in the sound collection device adopts a turning path design, which has a weakening effect on high-frequency sounds (such as the high-frequency sound part in wind noise and the high-frequency sound components generated by the fan system and other non-target noises), and has less influence on low-frequency sounds. Therefore, it can be better applied to the propagation of low-frequency noises in the sound collection device, facilitating the accurate collection of the sound collection element. Description of the Drawings

[0032] Figure 1 Schematic perspective view of the sound collection device according to Embodiment 1 of the present utility model;

[0033] Figure 2 Schematic perspective view of the sound collection device according to Embodiment 1 of the present utility model installed in the air duct;

[0034] Figure 3 Vertical sectional view of the sound collection device according to Embodiment 1 of the present utility model cut along the front-back direction;

[0035] Figure 4For Figure 3 Schematic structural diagram after removing the windproof sound transmission component;

[0036] Figure 5 Vertical sectional view of the sound collection device according to Embodiment 2 of the present utility model, sliced along the front-back direction;

[0037] Figure 6 Vertical sectional perspective view of the sound collection device according to Embodiment 2 of the present utility model, sliced along the front-back direction;

[0038] Figure 7 For Figure 5 Schematic structural diagram after removing the windproof sound transmission component. Specific embodiments

[0039] The present utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments.

[0040] In the description and claims of the present utility model, terms indicating directions such as "front", "rear", "upper", "lower", "left", "right", "side", "top", "bottom", etc. are used to describe various exemplary structural parts and elements of the present utility model. However, these terms are used here only for the purpose of convenience of description and are determined based on the exemplary orientations shown in the drawings. Since the embodiments disclosed by the present utility model can be arranged in different directions, these terms indicating directions are only for illustration and should not be regarded as limitations. For example, "upper" and "lower" are not necessarily limited to the directions opposite to or consistent with the direction of gravity.

[0041] Embodiment 1

[0042] Figures 1-4 A preferred embodiment of the sound collection device and the range hood of the present invention is shown.

[0043] The sound collection device includes a sound collection element 11 and a housing 2. A sound propagation channel is defined on the housing 2. Among them, the sound propagation channel includes a first channel section and a second channel section connected in sequence. Among them, the sound collection element 11 is located in the first channel section. The first channel section has a first sound inlet 211 communicating with the second channel section. The second channel section has a second sound inlet 45 for external sound to enter therein. The extension line of the opening direction of the first sound inlet 211 intersects with the extension line of the opening direction of the second sound inlet 45. In the preferred embodiment, both the first channel section and the second channel section are straight channels. Among them, the extension line of the first channel section intersects with the extension line of the second channel section.

[0044] The active noise reduction system is usually arranged in the air duct 10 of an oil fume suction device (such as a range hood or an integrated stove with an oil fume suction function and other kitchen appliances), and the sound collection device is an important part of the active noise reduction system and is also correspondingly arranged in the air duct 10 of the oil fume suction device. Taking the range hood as an example, the above-mentioned "air duct" can refer to the casing of the range hood or a box structure with a "channel" for the oil fume to pass through alone, such as the channel between the fan system and the smoke collecting hood of a ceiling-mounted range hood. The active noise reduction system generally includes a sound collection element 11 (microphone) and a speaker, that is, the microphone collects the noise generated when the range hood is working, and the collected noise sound wave is transmitted to the controller in the form of an electrical signal. After being analyzed and processed by the controller, an instruction is sent to the speaker to control the speaker to emit a sound wave matching the noise sound wave to neutralize the noise sound wave, thereby achieving the noise reduction effect. The sound collection device of this embodiment can be used to install the above-mentioned sound collection element 11 and provide protection against oil and wind.

[0045] The sound collection device is located below the fan system, that is, the noise generated by the fan system propagates downward along the air duct 10, and the sound collection device is exactly arranged on the downward propagation path in the air duct 10. In addition to the casing, the sound collection device also includes an oil-proof sound-permeable membrane 28 and a wind-proof sound-permeable member 30. The casing includes a mounting bracket 20 and a wind-proof cover 40.

[0046] In this embodiment, taking the box 1 with a "channel" for the oil fume to pass through alone as an example, the installation structure of the sound collection device is described, and the channel in the box 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 a receiving groove 21 for placing the sound collection element 11 is provided on its front side wall. This receiving groove constitutes the first channel section of the above-mentioned casing 2. The front part of the receiving groove 21 has an opening as the first sound inlet 211 for the sound to enter the receiving groove 21. Among them, the first sound inlet 211 should be understood as an opening for the sound from the outside (the sound collection channel in this embodiment) to enter the receiving groove 21 and be effectively collected by the sound collection element. In the state where the mounting bracket 20 is installed in place on the rear side wall of the air duct 10, the rear wall of the part of the mounting bracket 20 where the receiving groove 21 is located is attached to the rear side wall of the air duct 10. In order to improve the accuracy of sound collection of the active noise reduction system, generally two or more sound collection elements 11 are arranged. Therefore, components such as the mounting bracket 20, the wind-proof sound-permeable member 30, and the wind-proof cover 40 are also correspondingly provided with two or more.

[0047] The mounting bracket 20 further has a third mounting portion 263 extending respectively to the left and right sides and exposing outside the wind shield 40, and a fourth mounting portion 264 extending downward at the bottom of the mounting bracket 20 and exposing outside 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. At the lower region of the accommodation groove 21 of the mounting bracket 20, there is a connecting column 265 extending forward, and the wind shield 40 can be connected to the connecting column 265 of the mounting bracket 20 by screws 50.

[0048] The wind shield 40 includes a first side wall 411 and a second side wall 412 which are opposite to each other left and right and arranged at intervals, and a third side wall 413 connected between the front side edges of the first side wall 411 and the second side wall 412, whereby the wind shield 40 forms a housing structure with an open rear side. The third side wall 413 of the wind shield 40 is located at the front side of the accommodation groove 21 of the mounting bracket 20. On the third side wall 413 of the wind shield 40, there is a guiding surface 4130 that gradually inclines towards the inside of the air duct 10 along the air flow direction in the air duct 10 (such as Figure 2 the direction indicated by the hollow arrow in the figure). Specifically, the guiding 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, and it inclines forward from bottom to top, while the upper part of the third side wall 413 is basically arranged to extend vertically and is opposite to the part where the accommodation groove 21 of the mounting bracket 20 is located in the front-rear direction. Along the air flow direction in the air duct 10, the position where the guiding surface 4130 of the wind shield 40 is located is upstream of the position where the accommodation groove 21 of the mounting bracket 20 is located. Arranging the guiding surface 4130 of the wind shield 40 at a lower position also makes there be enough space at the position in the wind shield 40 opposite to the front part of the accommodation groove 21 to arrange components such as the windproof and sound-permeable member 30 and the first oil-proof and sound-permeable film 28. In addition, considering that if the inclination angle of the guiding surface 4130 towards the inside of the air duct 10 is too large, it will also affect the air flow in the air duct 10 to a certain extent, such as affecting the air volume flowing in the air duct 10 or generating additional noise problems. Therefore, the inclination angle of the guiding surface 4130 of the wind shield 40 needs to be reasonably designed. The included angle formed between the guiding surface 4130 of the wind shield 40 and the side wall of the air duct 10 for mounting the wind shield 40 is denoted as A, and the value range of A is: A ≤ 60°.

[0049] To improve the anti-oil pollution effect, the wind shield 40 of this embodiment can be made of plastic parts or metal parts.

[0050] In this embodiment, a gap channel extending vertically in the front-rear direction is formed between the wind shield 40 and the front side of the mounting frame 20. The upper end of the gap channel (i.e., the end close to the noise sound source) is open, and the lower end (i.e., the end far from the noise sound source) is closed, which is the sound collection channel 200. The sound collection channel 200 is located on the front side of the mounting frame 20, that is, it constitutes the second channel section of the above-mentioned housing 2. More specifically, a second sound inlet 45 communicating with the above-mentioned sound collection channel 200 is defined between the windward end of the wind shield 40 (i.e., a section along the extension direction of the air duct, close to the fan system of the range hood) and the front side wall of the mounting frame 20. That is, the opening direction of the second sound inlet 45 is upward. The air duct 10 and the sound collection channel 200 in this embodiment both extend vertically, that is, the extension direction of the sound collection channel 200 is the same as the extension direction B2 of the air duct 10. The opening direction B1 of the first sound inlet 211 is substantially perpendicular to the extension direction B3 of the sound collection channel 200.

[0051] The lower part of the sound collection channel 200 is opposite to the first sound inlet 211 at the front of the receiving groove 21 of the mounting frame 20 in the front-rear direction. After the wind shield 40 is installed, it can effectively prevent the high-speed oil fume airflow from directly impacting the wind-proof sound-transmitting member 30, greatly reducing the pollution of the oil fume to the wind-proof sound-transmitting member 30. At the same time, after the wind shield 40 and the mounting frame 20 are matched, only the upper second sound inlet 45 is retained, directly isolating the lower airflow noise and the noise interference of the secondary turbulent flow, so that the noise entering the wind-proof sound-transmitting member 30 mainly comes from above, that is, the main noise source direction of the range hood, thus ensuring the accuracy of noise collection.

[0052] Since the sound collection element 11 is installed in the accommodation groove 21 of the mounting bracket 20 and a windproof cover 40 is provided outside the mounting bracket 20, the interference of the air flow in the air duct 10 to the sound collection element 11 can be effectively isolated, and the sound collection element 11 can be prevented from being contaminated by the oil stain in the air flow. At the same time, a windproof and sound-permeable element 30 is provided in the sound collection channel formed between the mounting bracket 20 and the windproof cover 40, which can effectively reduce the influence of wind noise. Even if a small amount of air flow enters the sound collection channel 200, the pressure pulsation can be weakened in the windproof and sound-permeable element 30, thereby reducing the influence on the sound collection accuracy of the microphone. In addition, considering that the noise in the air duct 10 (mainly from the fan system) propagates along the extension direction of the air duct 10 and the propagation direction is opposite to the air flow direction in the air duct 10, therefore, arranging the sound collection channel 200 along the extension direction of the air duct can make the second sound inlet 45 of the sound collection channel 200 face the sound source, so as to directly receive the noise. And considering that a windproof and sound-permeable element 30 with a sufficient length needs to be provided on the sound propagation path to prevent wind noise, thereby reducing the influence of the air flow in the air duct 10 on sound collection. In this embodiment, the sound collection channel 200 for placing the windproof and sound-permeable element 30 is arranged in the extension direction of the air duct 10, so that the size of the entire sound collection device in the direction perpendicular to the extension direction of the air duct can be made smaller, that is, it occupies less space in the air duct 10 of the range hood, and further makes the wind resistance at the position of the sound collection device in the air duct 10 smaller. Therefore, it will not affect the stability of the air flow in the air duct 10 and at the same time reduce the generation of wind noise to a certain extent. On this basis, considering that the air duct environment of the range hood is full of oil stains, if the opening direction B1 of the first sound inlet 211 is the same as the extension direction B3 of the sound collection channel 200, then the sound collection element 11 is easily contaminated by the oil stains flowing down along the air duct 10. Therefore, in this embodiment, the opening direction B1 of the first sound inlet 211 of the accommodation groove 21 is perpendicular to the extension direction B3 of the sound collection channel 200, which makes the entire sound propagation path from the noise in the air duct 10 entering the sound collection channel 200 through the second sound inlet 45 and then propagating to the position of the sound collection element 11 in the accommodation groove 21 a turning path. This turning path can prevent too much oil stain from directly passing through the sound collection channel 200 and contacting the sound collection element 11, but make most of the oil stains adhere to the side wall of the sound collection channel 200 or the windproof and sound-permeable element 30, thereby enabling the sound collection element 11 to be as far away from the oil stain as possible and extending the service life of the sound collection element 11.Furthermore, considering that the target noise to be collected by the active noise cancellation system (mainly from the fan system) is low-frequency noise, the sound propagation path in the sound collection device adopts a turning path design, which has a weakening effect on high-frequency sounds (such as the high-frequency sound components in wind noise and the high-frequency sound components generated by the fan system, etc., which are non-target noises), and has little impact on low-frequency sounds. Therefore, it can be well applied to the propagation of low-frequency noise in the sound collection device, which is beneficial for the sound collection element 11 to accurately collect it. The main reason is that the wavelength of low-frequency noise is longer, and it can better adapt to the bending and irregular shapes of the pipeline. When low-frequency noise propagates in a curved pipeline, due to its longer wavelength, it is not easily blocked and reflected by the pipeline, so it can better propagate and spread. While the wavelength of high-frequency noise is shorter, it is easily reflected and absorbed by the shape and bending of the pipeline, so it is more difficult to propagate and spread in the pipeline than low-frequency noise.

[0053] The first oil-proof sound-permeable membrane 28 covers the first sound inlet 211 of the receiving groove 21 of the mounting frame 20, specifically, it is installed at the position of the edge of the front opening of the receiving groove 21 of the mounting frame 20. More specifically, in order to facilitate the installation of the first oil-proof sound-permeable membrane 28 and ensure its sealing performance after installation, an annular step portion 210 is further formed at the edge position of the first sound inlet 211 of the receiving groove 21, and the first oil-proof sound-permeable membrane 28 is arranged on the annular step portion 210. In order to ensure the oil-proof performance of the first oil-proof sound-permeable membrane 28 and enable it to effectively transmit sound waves, the first oil-proof sound-permeable membrane 28 of this embodiment is preferably a polyethylene film. Among them, there is a fourth distance between the first oil-proof sound-permeable membrane 28 and the sound collection element 11, which is denoted as f. Among them, the value range of f is: f≥2mm. Thus, it is avoided that the film vibrates or undergoes micro-deformation and contacts the sound collection element 11, resulting in sound propagation variation and affecting the accuracy of sound collection. It can be understood that the above-mentioned fourth distance f between the first oil-proof sound-permeable membrane 28 and the sound collection element 11 should refer to the distance between the first oil-proof sound-permeable membrane 28 and the microphone chip on the sound collection element 28, that is, the first oil-proof sound-permeable membrane 28 and other components (such as solder joints or fixing screws, etc.) on the circuit board where the microphone chip is located can have partial contact. The wind-proof sound-permeable member 30 does not directly contact the first oil-proof sound-permeable membrane 28 to ensure the oil-proof effect. Specifically, there is a sixth distance between the first oil-proof sound-permeable membrane 28 and the main body of the wind-proof sound-permeable member 30 in the front-rear direction. In order to avoid the first oil-proof sound-permeable membrane 28 contacting the wind-proof sound-permeable member 30 and affecting the sound transmission effect here, the sixth distance should be greater than 0.1mm, and the preferred range is 0.5mm - 3mm.

[0054] In order to effectively slow down the air flow and eliminate the air flow impact, the windproof sound-transmitting member 30 is a sound-transmitting member made of porous sound-absorbing material. For example, the windproof sound-transmitting member 30 can be made of polyurethane foam, melamine foam sponge, etc. Among them, the porosity of the windproof sound-transmitting member 30 is greater than 70%. The windproof sound-transmitting member 30 of this embodiment can not only prevent the air flow from impacting the first oil-proof sound-transmitting membrane 28 and generating additional noise, but also absorb the high-frequency components in the sound energy due to the property of its porous material itself, realizing the filtering function of filtering the noise signal. Specifically, the front side wall of the windproof sound-transmitting member 30 is attached to the rear side wall of the third side wall 413 of the windproof cover 40, so that the windproof sound-transmitting member 30 is in a compressed state. By compression, the material density can be increased, and the possibility of the penetration of the air flow pressure pulsation can be effectively reduced, thereby further improving the windproof effect.

[0055] An oil-proof sound-transmitting member is also provided at the second sound inlet 45. The oil-proof sound-transmitting member of this embodiment is the second oil-proof sound-transmitting membrane 282 covering the second sound inlet, and the second oil-proof sound-transmitting membrane 282 is also made of polyethylene film. Specifically, the second oil-proof sound-transmitting membrane 282 covers the windproof sound-transmitting member 30, which can effectively prevent oil stains from entering the sound collection channel 200, polluting the windproof sound-transmitting member 30, and affecting the windproof and sound-transmitting effects of the windproof sound-transmitting member 30. Specifically, the top edge of the windproof cover 40 is higher than the top edge of the mounting bracket 20, and the second oil-proof sound-transmitting membrane 282 inclines downward toward the position of the mounting bracket 20 from top to bottom (inclines downward from front to back). Among them, the top edge of the second oil-proof sound-transmitting membrane 282 is connected to the inner wall surface of the third side wall 413 of the windproof cover 40, the left and right edges of the second oil-proof sound-transmitting membrane 282 are respectively connected to the inner wall surfaces of the first side wall 411 and the second side wall 412 of the windproof cover 40, and the bottom edge of the second oil-proof sound-transmitting membrane 282 is connected to the top edge of the mounting bracket 20. In addition, the top of the windproof sound-transmitting member 30 in the sound collection channel 200 is also designed as an inclined surface, which also inclines downward toward the position of the mounting bracket 20 from top to bottom, that is, the inclination direction of the inclined surface at the top of the windproof sound-transmitting member 30 is basically the same as the inclination direction of the second oil-proof sound-transmitting membrane 282. The second oil-proof sound-transmitting membrane 282 is arranged obliquely, so that the oil stains flowing onto or dripping onto the second oil-proof sound-transmitting membrane 282 can quickly fall off under the action of their own gravity, avoiding the oil stains from hanging on the surface of the second oil-proof sound-transmitting membrane 282 for a long time. On the other hand, the second oil-proof sound-transmitting membrane 282 can also play a role in wind noise prevention, reducing the transmission of the pressure pulsation formed by the sudden change of the air flow at the second sound inlet 42 into the sound collection channel, and improving the adverse impact on the accuracy of sound collection.

[0056] This embodiment also relates to a range hood, including a flue 10 for the passage of flue gas and an active noise reduction system provided in the flue 10, and the active noise reduction system includes the above-mentioned sound collection device.

[0057] Embodiment 2

[0058] Figures 5-7 Another preferred embodiment of the sound collection device and the range hood of the present utility model is shown. The difference between this embodiment and Embodiment 1 is that: at the top opening of the sound collection channel 200 formed between the wind shield 40 and the mounting bracket 20 (i.e., at the second sound inlet 45), there is also provided an oil-blocking and sound-permeable plate 47 (replacing the second oil-blocking and sound-permeable film 282), and the oil-blocking and sound-permeable plate 47 covers the wind-shielding and sound-permeable member 30. The oil-blocking and sound-permeable plate 47 can also prevent oil stains from entering the sound collection channel 200, contaminating the wind-shielding and sound-permeable member 30, and affecting the wind-shielding and sound-permeable effects of the wind-shielding and sound-permeable member 30. Specifically, the top edge of the wind shield 40 is higher than the top edge of the mounting bracket 20. Among them, the oil-blocking and sound-permeable plate 47 inclines downward toward the position where the mounting bracket 20 is located. The top edge of the oil-blocking and sound-permeable plate 47 is connected to the inner wall surface of the third side wall 413 of the wind shield 40. The left and right edges of the oil-blocking and sound-permeable plate 47 are respectively connected to the inner wall surfaces of the first side wall 411 and the second side wall 412 of the wind shield 40, and the bottom edge of the oil-blocking and sound-permeable plate is connected to the top edge of the mounting bracket 20, specifically above the top edge of the mounting bracket 20. Sound transmission holes 470 are distributed on the oil-blocking and sound-permeable plate 47 of this embodiment, and the sound in the air duct 10 can be transmitted to the sound collection channel 200 through the above-mentioned sound transmission holes 470. In order to prevent oil stains from entering the sound collection channel 200 through the sound transmission holes 470 and contaminating the wind-shielding and sound-permeable member 30, an annular blocking edge 471 extending upward is provided along the periphery of each sound transmission hole 470. An oil-proof coating can also be added to the top surface of the oil-blocking and sound-permeable plate 47 to prevent oil stains from adhering to its top surface. Of course, an oil-proof film (not shown) can also be added to the side wall of the oil-blocking and sound-permeable plate 47 facing the sound collection channel 200, and the oil-proof film covers each sound transmission hole to improve the oil-proof effect. The oil-blocking and sound-permeable plate 47 and the wind shield 40 of this embodiment are integrally designed, that is, the oil-blocking and sound-permeable plate and the main body of the wind shield 40 are integrally formed. Of course, it can be imagined that the oil-blocking and sound-permeable plate 47 can also be integrally designed with the mounting bracket 20, that is, the oil-blocking and sound-permeable plate and the main body of the mounting bracket 20 are integrally formed.

[0059] The top of the wind-shielding and sound-permeable member 30 in the sound collection channel 200 is also designed as an inclined surface, which also inclines downward toward the position where the mounting bracket 20 is located. That is, the inclination direction of the inclined surface at the top of the wind-shielding and sound-permeable member 30 is basically the same as the inclination direction of the oil-blocking and sound-permeable plate 47.

[0060] This embodiment also relates to a range hood, which includes an air duct 10 for the flue gas to pass through and an active noise reduction system provided in the air duct 10. The active noise reduction system includes the above-mentioned sound collection device.

Claims

1. A sound collection device is disposed in the air duct (10) of an oil fume suction device, and includes a housing (2) and a sound collection element (11) disposed in the housing (2), and is characterized in that: A sound propagation channel is defined on the housing (2). The sound propagation channel includes a second channel section arranged along the extending direction of the air duct (10). At the leeward end of the housing (2), a second sound inlet (45) is formed and communicated with the second channel section for the sound in the air duct (10) to enter the second channel section. The opening direction of the second sound inlet (45) is consistent with the extending direction of the air duct (10). An oil-proof sound-permeable member is also provided at the second sound inlet (45).

2. The sound collection device according to claim 1, wherein: The sound propagation channel further includes a first channel section communicated with the second channel section and arranged at an angle. The sound collection element (11) is arranged in the first channel section.

3. The sound collection device according to claim 2, characterized in that: The first channel section has a first sound inlet (211) communicated with the second channel section. The extension line of the opening direction of the first sound inlet (211) is perpendicular to the extending direction of the second channel section.

4. The sound collection device according to claim 2 or 3, characterized in that: The housing (2) includes a mounting bracket (20) and a wind shield (40). A receiving groove (21) is formed on the front side wall of the mounting bracket (20). The sound collection element (11) is placed in the receiving groove (21). The receiving groove (21) constitutes the first channel section. The front opening of the receiving groove (21) serves as the first sound inlet (211). The wind shield (40) is sleeved outside the mounting bracket (20), and a sound collection channel (200) communicated with the first sound inlet (211) of the receiving groove (21) and located at the front side of the receiving groove (21) is defined between the wind shield (40) and the mounting bracket (20). The sound collection channel (200) constitutes the second channel section.

5. The sound collection device according to claim 4, wherein: The oil-proof sound-permeable member is a second oil-proof sound-permeable membrane (282) covering the second sound inlet (45).

6. The sound collection device according to claim 5, wherein: The second channel section extends vertically. The opening direction of the second sound inlet (45) faces upward. The second oil-proof sound-permeable membrane (282) inclines downward from front to back.

7. The sound collection device according to claim 6, wherein: The top of the mounting bracket (20) is lower than the top of the wind shield (40). The front side of the second oil-proof sound-permeable membrane (282) is connected to the rear side wall of the wind shield (40), and the rear side of the second oil-proof sound-permeable membrane (282) is connected to the top of the mounting bracket (20).

8. The sound collecting device according to claim 4, characterized in that: The oil-proof sound-permeable member is an oil-blocking sound-permeable plate (47) covering the second sound inlet (45). Sound-permeable holes (470) are distributed on the oil-blocking sound-permeable plate (47).

9. The sound collection device according to claim 8, wherein: An upward-extending annular blocking edge (471) is further provided along the circumferences of the sound-permeable holes (470) on the oil-blocking sound-permeable plate (47).

10. The sound collection device according to claim 8, wherein: The second channel section extends vertically. The opening direction of the second sound inlet (45) faces upward. The oil-blocking sound-permeable plate (47) inclines downward from front to back.

11. The sound collection device according to claim 8, wherein: The oil-blocking sound-permeable plate (47) is integrally designed with the wind shield or the mounting bracket (20).

12. The sound collection device according to claim 4, wherein: A wind-proof sound-permeable member (30) is also provided in the sound collection channel (200).

13. The sound collection device according to claim 4, wherein: A first oil-proof sound-permeable membrane (28) is also provided at the first sound inlet (211).

14. An oil fume extractor, comprising an air duct (10) for flue gas to pass through and a sound collection device disposed in the air duct (10), characterized in that: The described sound acquisition device adopts the sound acquisition device described in any one of claims 1 to 13.

15. The range hood according to claim 14, wherein: The described sound acquisition element (11) is a microphone.

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