Microphone assembly for active noise reduction and extractor hood

Abstract

The application discloses a kind of microphone assembly and extractor hood for active noise reduction, and microphone assembly for active noise reduction includes: microphone and flow guide cover, flow guide cover is oppositely arranged with the pickup surface of microphone;There is a gap for pickup between flow guide cover and pickup surface, and the gap is communicated with the pickup hole of microphone.The application is by additionally adding flow guide cover, so that and there is a gap for pickup between flow guide cover and the pickup surface of microphone, sound can directly enter the pickup hole of microphone through the gap, since narrow gap will form acoustic resistance, most airflow flows away from the surface of flow guide cover, a small part of airflow will enter the gap, but flow speed will be reduced, and flow is smooth, without changing flow direction directly from the gap, so airflow will not enter pickup hole, airflow can directly flow out through the gap, avoid producing wind noise, drainage without introducing wind noise, without affecting microphone to collect sound signal, to improve the noise reduction effect of active noise reduction.

Description

Technical Field

[0001] This invention relates to the field of home appliance technology, and in particular to a microphone assembly for active noise cancellation and a range hood. Background Technology

[0002] The fan of a range hood is a significant noise source. Current technology uses components such as microphones and speakers for active noise cancellation to reduce the noise of the range hood. However, the microphone's open installation structure can generate wind noise due to the wind speed, which can be picked up by the microphone and ultimately affect the noise reduction effect of the active noise cancellation. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the defect that the microphone components in the prior art are prone to wind noise, resulting in poor noise reduction effect, and to provide a microphone component and range hood for active noise reduction.

[0004] The present invention solves the above-mentioned technical problems through the following technical solution:

[0005] In a first aspect, a microphone assembly for active noise cancellation is provided, the microphone assembly for active noise cancellation comprising: a microphone and a flow guide cover, the flow guide cover being disposed opposite to the pickup surface of the microphone;

[0006] There is a gap between the air guide cover and the sound pickup surface for sound pickup, and the gap is connected to the sound pickup hole of the microphone.

[0007] Optionally, the gap gradually increases along the central axis of the flow guide cover;

[0008] And / or, the area of ​​the flow guide cover is smaller than the area of ​​the sound pickup surface;

[0009] And / or, the side of the flow guide cover away from the sound pickup surface protrudes;

[0010] And / or, the roughness of the side of the flow guide cap away from the sound pickup surface is less than the roughness threshold;

[0011] And / or, the microphone assembly is oval in shape.

[0012] Optionally, the side of the flow guide cap away from the sound pickup surface has a raised structure.

[0013] Optionally, the flow guide cover is provided with a rotating shaft, the microphone pickup surface is provided with a support, the support forms a receiving cavity, and the rotating shaft is inserted into the receiving cavity; the side of the flow guide cover opposite to the gap is provided with an oil stain cleaning device;

[0014] When the flow guide cover rotates around the rotation axis, the oil stain cleaning device rotates with the flow guide cover to clean the oil stains in the gap.

[0015] Optionally, the inner wall surface of the pickup hole is provided with a first sound insulation component;

[0016] And / or, a protective film is provided at the opening of the pickup hole near the gap; the protective film includes at least one of the following: a waterproof film, a breathable film, and a waterproof and breathable film;

[0017] And / or, the microphone includes a sound pressure sensor, the sound pressure sensor is provided with a second sound insulation component, and the sound inlet of the sound pressure sensor is connected to the pickup hole.

[0018] Optionally, the gap between the flow guide cover and the sound pickup surface is in the range of 0.2mm-1mm;

[0019] And / or, the protrusion height of the protrusion structure is greater than 2 mm;

[0020] And / or, the thickness of the first sound insulation component is greater than 1 mm.

[0021] In a second aspect, a range hood is provided, the range hood comprising: a speaker, an air duct, and a microphone assembly for active noise cancellation as described in any one of the above; the microphone assembly and the speaker are disposed on the inner wall surface of the air duct.

[0022] Optionally, the range hood further includes a fan assembly; the fan assembly is connected to the duct via a flexible pipe.

[0023] Optionally, the range hood further includes: a lifting push rod; the air duct includes: a lifting cavity and a smoke collection cavity;

[0024] The lifting push rod connects the lifting cavity and the smoke collection cavity; the lifting push rod is used to control the lifting height of the lifting cavity.

[0025] Optionally, the range hood includes at least two sets of microphone assemblies, which are placed side by side;

[0026] The distance between the at least two sets of microphone assemblies is greater than 10cm;

[0027] And / or, the distance between the microphone assembly and the speaker is greater than 18cm.

[0028] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of the present invention.

[0029] The positive and progressive effects of this invention are as follows: By adding a flow guide cover, and with a gap between the flow guide cover and the microphone's pickup surface for sound pickup, sound can directly enter the microphone's pickup hole through the gap. Since the narrow gap will create acoustic resistance, most of the airflow will flow away from the surface of the flow guide cover, and a small portion of the airflow will enter the gap, but the flow speed will be reduced and the flow will be smooth, flowing out directly from the gap without changing the flow direction. Therefore, the airflow will not enter the pickup hole, avoiding wind noise and not affecting the microphone's acquisition of sound signals, thereby improving the noise reduction effect of active noise cancellation. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of a microphone assembly for active noise cancellation provided in an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of a microphone assembly for active noise cancellation provided in an embodiment of the present invention;

[0032] Figure 3 A cross-sectional view of a microphone assembly for active noise cancellation provided in an embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of a range hood module provided in an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram illustrating the effect of a range hood according to an embodiment of the present invention. Detailed Implementation

[0035] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.

[0036] This invention provides a microphone assembly 31 for active noise cancellation, see [link to documentation]. Figure 1 and Figure 2 The microphone assembly 31 for active noise cancellation includes a microphone 11 and a flow deflector 12.

[0037] The airflow deflector 12 is positioned opposite the pickup surface of the microphone 11. For example... Figure 3 As shown, there is a gap 13 between the air guide cover 12 and the sound pickup surface for sound pickup, and the gap 13 is connected to the sound pickup hole 14 of the microphone 11.

[0038] The microphone assembly 31 used for active noise cancellation is mainly used to pick up the noise signal generated by the fan of the range hood. Other interfering noises, such as wind noise, need to be removed. Especially when applied in the air duct 33 of the range hood, wind noise becomes the main source of interference, which greatly affects the microphone 11's ability to pick up noise signals, and thus affects the noise reduction effect of active noise cancellation.

[0039] Understandably, the airflow cover 12 can prevent the microphone 11 from being directly blown by the airflow in the air duct 33. Sound signals from above, below, left, and right can directly enter the microphone 11's pickup hole 14 through the gap 13 between the airflow cover 12 and the pickup surface. Most of the airflow will flow away directly from the side of the airflow cover 12 away from the pickup surface. The flow speed of a small portion of the airflow entering through the gap 13 will also be reduced, and it will flow directly out of the microphone assembly 31 through the gap 13.

[0040] In this embodiment, by adding a flow guide cover 12, and there is a gap 13 between the flow guide cover 12 and the sound pickup surface of the microphone 11 for sound pickup, most of the airflow flows away from the surface of the flow guide cover, and a small part of the airflow will enter the gap, but the flow speed will be reduced and it will flow out directly from the gap without changing the flow direction. Therefore, the airflow will not enter the sound pickup hole, avoiding wind noise and not affecting the microphone 11 to pick up the sound signal, thereby improving the noise reduction effect of active noise cancellation.

[0041] In one embodiment, the gap 13 gradually increases along the central axis of the flow guide cover 12.

[0042] If airflow enters one side opening 15 of gap 13 and flows along the central axis of guide cover 12 within gap 13, the cross-section of gap 13 increases as gap 13 gradually enlarges along the central axis of guide cover 12. According to the principle of a widening tube, the airflow velocity within gap 13 decreases, and the airflow exits from the central axis of guide cover 12 to the other side opening of gap 13. Because the airflow velocity within gap 13 is relatively low, the generated wind noise is low, and therefore it does not affect the microphone 11's ability to pick up sound signals, thus achieving the noise reduction effect of active noise cancellation.

[0043] In this embodiment, the gap 13 gradually increases along the central axis of the guide cover 12, so that the flow speed of the airflow entering the gap 13 gradually decreases, avoiding wind noise interference, which helps the microphone 11 to pick up the required sound signal more accurately, improves the clarity of the sound signal picked up by the microphone 11, enhances the performance of the microphone 11, and enables the microphone 11 to perform the active noise cancellation function more effectively, thereby improving the effect of active noise cancellation.

[0044] In one embodiment, the area of ​​the flow guide cover 12 is smaller than the area of ​​the sound pickup surface.

[0045] In this embodiment, the area of ​​the flow guide cover 12 is smaller than the area of ​​the sound pickup surface. The smaller flow guide cover 12 helps to maintain the quality of the sound signal, reduces the impact on the sound signal, helps the microphone 11 to pick up the required sound signal more accurately, and can reduce the overall size and weight of the microphone assembly 31. The structure is simple and easy to implement.

[0046] In one embodiment, the roughness of the side of the flow guide 12 away from the sound pickup surface is less than a roughness threshold.

[0047] If the microphone assembly 31 is placed on the inner wall of the air duct 33 of the range hood, a high-speed airflow will be generated in the air duct 33. In order to ensure that the guide cover 12 does not obstruct the high-speed airflow, the roughness of the side of the guide cover 12 facing the air duct 33 needs to be less than the roughness threshold, that is, the roughness of the side of the guide cover 12 away from the sound pickup surface is less than the roughness threshold.

[0048] The roughness threshold can be selected according to the actual situation and is not specifically limited here. Understandably, the smaller the roughness, the smoother the side of the air deflector 12 away from the sound pickup surface, and the less likely it is to obstruct high-speed airflow.

[0049] In this embodiment, the side of the guide cover 12 away from the sound pickup surface is smoother, which can reduce the frictional resistance of the airflow in the air duct 33, improve the stability of the airflow, help reduce the noise generated when the airflow passes through, prevent aerodynamic noise, and thus improve the noise reduction effect.

[0050] In one embodiment, the microphone assembly 31 is oval-shaped.

[0051] In this embodiment, the flat, round microphone assembly 31 is less likely to obstruct airflow, improving airflow stability, helping to reduce noise generated when airflow passes through, preventing aerodynamic noise, and thus improving the noise reduction effect.

[0052] In one embodiment, the flow guide cover 12 is provided with a rotating shaft 16, and the microphone 11 has a support 17 on its pickup surface. The support 17 forms a receiving cavity, and the rotating shaft 16 is inserted into the receiving cavity. An oil stain cleaning device 18 is provided on the side of the flow guide cover 12 opposite to the gap 13. When the flow guide cover 12 rotates around the rotating shaft 16, the oil stain cleaning device 18 rotates with the flow guide cover 12 to clean the oil stains in the gap 13.

[0053] If the microphone assembly 31 is placed in an oily fume environment, oil stains will clog the gap 13, affecting the microphone 11's collection of noise signals. Therefore, an oil stain cleaning device 18 is required to prevent excessive oil stains from accumulating in the gap 13.

[0054] Specifically, when the range hood is running, the airflow passes over the guide cover 12. The collision and friction with the guide cover 12 generates asymmetrical resistance, pushing it to rotate around the rotation axis 16. This, in turn, causes the oil stain cleaning device 18 mounted on the guide cover 12 to clean the oil stains in the gap 13, preventing the formation of old, solidified grease. The oil stain cleaning device 18 rotates with the guide cover 12, with a rotation range of 360°.

[0055] The oil stain cleaning device 18 includes, but is not limited to: silicone brush, sponge brush and ball brush. The specific type can be set according to the actual situation and is not particularly limited here.

[0056] In this embodiment, a rotating shaft 16 is provided on the guide cover 12. The airflow allows the guide cover 12 to rotate around the rotating shaft 16, thereby driving the oil stain cleaning device 18 provided on the guide cover 12 to clean the oil stains in the gap 13, reducing the oil stains attached to the inner wall of the gap 13, and preventing the formation of old and solidified grease.

[0057] In one embodiment, the number of oil stain cleaning devices 18 is at least two, and the at least two oil stain cleaning devices 18 are symmetrically distributed on the guide cover 12.

[0058] Understandably, through symmetrical distribution, the oil stain cleaning device 18 can cover a wider pickup surface. This allows for faster processing of large areas of oil stains, improving cleaning efficiency. The number of oil stain cleaning devices 18 can be set according to actual conditions and is not specifically limited here.

[0059] In this embodiment, the number of oil stain cleaning devices 18 is at least two, and the at least two oil stain cleaning devices 18 are symmetrically distributed on the guide cover 12, which improves the cleaning efficiency and helps to improve the cleaning effect, avoid dead corners or uncleaned areas, and improve the stability of oil stain cleaning.

[0060] In one embodiment, the side of the flow guide 12 away from the pickup surface has a raised structure 19.

[0061] Understandably, the deflector 12 with the raised structure 19 is more susceptible to the propulsion of airflow and rotates when the wind direction changes.

[0062] The number of raised structures 19 is an odd number, usually around 3, 5 or 7. The specific number can be set according to the actual situation, and no special limit is made here.

[0063] In this embodiment, the side of the flow guide cover 12 away from the sound pickup surface has a raised structure 19, which can resist the airflow to form a driving force, making it easy for the flow guide cover 12 to rotate around the rotation axis 16, which helps to drive the oil stain cleaning device 18 provided on the flow guide cover 12 to clean the oil stains in the gap 13. The structure is simple and easy to implement.

[0064] In one embodiment, the inner wall surface of the pickup hole 14 is provided with a first sound insulation component 20.

[0065] The material of the first sound insulation component 20 includes, but is not limited to, sound insulation rubber. The specific material can be selected according to the actual situation and is not specifically limited here.

[0066] In this embodiment, by providing a first sound insulation component 20 on the inner wall of the pickup hole 14, the sound signal entering the pickup hole 14 will not be reflected or vibrated, thus avoiding affecting the quality of the sound signal. This helps the microphone 11 to pick up the required sound signal more accurately, enabling the microphone 11 to perform the active noise cancellation function more effectively, thereby improving the effect of active noise cancellation.

[0067] In one embodiment, the microphone 11 includes a PCB board 21, and one end of the first sound insulation component 20 is press-fitted to the PCB board 21.

[0068] Using interference compression can achieve a tight connection between the first sound insulation component 20 and the PCB board 21, ensuring that the first sound insulation component 20 and the PCB board 21 do not loosen during the use of the microphone assembly 31, and can improve the sealing performance.

[0069] In this embodiment, by pressurizing one end of the first sound insulation component 20 with the PCB board 21, it is ensured that the first sound insulation component 20 and the PCB board 21 do not become loose or move relative to each other, and it helps to improve the sealing performance, ensuring that the sound signal entering the pickup hole 14 will not be reflected or vibrated, thus avoiding affecting the quality of the sound signal.

[0070] In one embodiment, the pickup hole 14 is provided with a protective membrane 22 near the opening of the gap 13. The protective membrane 22 includes at least one of the following: a waterproof membrane, a breathable membrane, and a waterproof and breathable membrane.

[0071] The protective film 22 can be selected according to the actual situation, and no special restrictions are made here.

[0072] In this embodiment, a protective film 22 is provided at the opening of the pickup hole 14 near the gap 13 to ensure that oil stains do not enter the pickup hole 14. This helps the microphone 11 to pick up the required sound signal more accurately, improves the service life of the microphone 11, enhances the performance of the microphone 11, and enables the microphone 11 to perform the active noise cancellation function more effectively, thereby improving the effect of active noise cancellation.

[0073] In one embodiment, the other end of the first sound insulation component 20 is pressurized against the protective film 22.

[0074] Using interference compression can achieve a tight connection between the first sound insulation component 20 and the protective film 22, ensuring that the first sound insulation component 20 and the protective film 22 do not loosen during the use of the microphone assembly 31, and can improve the sealing performance.

[0075] In this embodiment, by pressurizing the other end of the first sound insulation component 20 with the protective film 22, it is ensured that the first sound insulation component 20 and the protective film 22 do not loosen or move relative to each other, and it helps to improve the sealing performance, ensuring that the sound signal entering the pickup hole 14 will not be reflected or vibrated, thus avoiding affecting the quality of the sound signal.

[0076] In one embodiment, the microphone 11 includes a sound pressure sensor 23, the sound pressure sensor 23 is provided with a second sound insulation component 24, and the sound inlet 25 of the sound pressure sensor 23 is connected to the pickup hole 14.

[0077] The sound pressure sensor 23 is enclosed by the second sound insulation component 24. The sound pressure sensor 23 includes, but is not limited to, a silicon microphone sensor, and the material of the second sound insulation component 24 includes, but is not limited to, sound-insulating rubber. The specific material can be selected according to the actual situation and is not specifically limited here.

[0078] In this embodiment, the microphone 11 includes a sound pressure sensor 23. The sound inlet 25 of the sound pressure sensor 23 is connected to the pickup hole 14, so that sound can enter the sound inlet 25 through the pickup hole 14 and be picked up by the sound pressure sensor 23. The second sound insulation component 24 is provided to ensure that the sound signal entering the sound inlet 25 will not be reflected or vibrated, thus avoiding affecting the quality of the sound signal.

[0079] In one embodiment, the size of the gap 13 ranges from 0.2 mm to 1 mm.

[0080] The size of gap 13 can be set according to the actual situation, and no special limitation is made here.

[0081] In this embodiment, the size of the gap 13 is in the range of 0.2mm-1mm. Since the narrow gap 13 will form an acoustic barrier, most of the airflow will flow away from the surface of the guide cover 12. A small part of the airflow will enter the gap, but the flow speed will be reduced and the flow will be smooth. It will flow out directly from the gap without changing the flow direction. Therefore, the airflow will not enter the pickup hole 14, avoiding wind noise. The airflow is diverted without introducing wind noise, which does not affect the microphone 11 from picking up the sound signal, thereby improving the noise reduction effect of active noise cancellation.

[0082] In one embodiment, the protrusion height of the protrusion structure 19 is greater than 2 mm.

[0083] Understandably, a higher protrusion provides greater resistance to airflow, but an excessively high protrusion would result in an overly large microphone assembly 31. The protrusion height can be set according to actual conditions and is not specifically limited here.

[0084] In this embodiment, the side of the flow guide cover 12 away from the sound pickup surface has a raised structure 19, which can resist the airflow to form a driving force, making it easy for the flow guide cover 12 to rotate around the rotation axis 16, which helps to drive the oil stain cleaning device 18 provided on the flow guide cover 12 to clean the oil stains in the gap 13. The structure is simple and easy to implement.

[0085] In one embodiment, the thickness of the first sound insulation component 20 is greater than 1 mm.

[0086] The thickness of the first sound insulation component 20 can be set according to the actual situation, and no special limit is made here.

[0087] In this embodiment, the thickness of the first sound insulation component 20 is greater than 1mm, ensuring that the sound signal entering the pickup hole 14 will not be reflected or vibrated, thus avoiding affecting the quality of the sound signal. This helps the microphone 11 to pick up the required sound signal more accurately, enabling the microphone 11 to perform the active noise cancellation function more effectively, thereby improving the effect of active noise cancellation.

[0088] This invention also provides a range hood, see [link to relevant documentation]. Figure 4 and Figure 5 The range hood includes: a speaker 32, an air duct 33, and a microphone assembly 31 for active noise cancellation, which is one of the above. The microphone assembly 31 and the speaker 32 are disposed on the inner wall of the air duct 33.

[0089] The air duct 33 includes an upper air duct 33 and a lower air duct 33. The microphone assembly 31 can be set on the inner wall of the upper air duct 33, and the speaker 32 can be set on the inner wall of the lower air duct 33. The microphone assembly 31 and the speaker 32 can be set according to the actual situation, and no special limitation is made here.

[0090] The microphone assembly 31 can be installed on the front, back, left, and right sides of the inner wall of the air duct 33. It should be noted that the front side of the inner wall is the side facing the cooktop platform, and the rear side of the inner wall is the side away from the cooktop platform.

[0091] The experimental results show that when the microphone assembly 31 is placed on the rear side of the inner wall of the air duct 33, the wind noise is minimized, the impact on the noise reduction effect is minimal, and the production and assembly are the most convenient.

[0092] The range hood also includes a controller. The controller is used to receive the sound signal picked up by the microphone assembly 31, analyze the sound signal to obtain the corresponding inverse signal, and control the speaker 32 to emit the inverse signal to neutralize the sound signal.

[0093] In this embodiment, the microphone assembly 31 and the speaker 32 are disposed on the inner wall of the air duct 33 of the range hood to minimize obstruction of the airflow in the air duct 33 and avoid generating interfering wind noise. After the microphone assembly 31 picks up the sound signal, the speaker 32 emits a counter signal to neutralize the sound signal, so that the human ear hears the neutralized sound signal, thereby improving the user experience.

[0094] In one embodiment, the range hood further includes a fan assembly 34. The fan assembly 34 is connected to the duct 33 via a flexible tube 35.

[0095] The range hood's fan assembly 34 is placed inside the ceiling to reduce the noise generated by the fan assembly 34 from affecting the user. The air inlet is close to the cooktop platform to improve the smoke extraction effect.

[0096] In this embodiment, the fan assembly 34 and the air duct 33 are connected by a flexible tube 35, which reduces the degree of vibration of the fan assembly 34 transmitted to the air duct 33. Reducing vibration helps to improve the overall stability and safety of the range hood, and can also reduce noise, reduce wear of parts caused by vibration, and thus extend the service life of the range hood.

[0097] In one embodiment, the range hood further includes a lifting push rod 36. The air duct 33 includes a lifting cavity and a smoke collection cavity 37.

[0098] The lifting push rod 36 connects the lifting cavity and the smoke collection chamber 37, and is used to control the lifting height of the lifting cavity. When the range hood is not in use, the lifting push rod 36 can be controlled to allow the lifting cavity to fully retract and embed itself into the cabinet. When the range hood is needed to remove fumes, such as when simmering soup or stir-frying, the lifting push rod 36 can be controlled to adjust the height of the lifting cavity, thereby controlling the lowering height of the smoke collection chamber 37 to meet the user's needs.

[0099] In this embodiment, a lifting push rod 36 is used to connect the lifting cavity and the smoke collection cavity 37. The structure is simple and easy to implement. It can control the lifting cavity to contract or descend, thereby controlling the height of the smoke collection cavity 37 connected to the lifting cavity. This ensures that the height of the smoke collection cavity 37 meets the user's needs and improves the user experience.

[0100] In one embodiment, the range hood includes at least two sets of microphone assemblies 31, which are placed side by side.

[0101] The number of microphone components 31 can be four, and the specific number can be set according to the actual situation. No special limit is made here.

[0102] In this embodiment, at least two sets of microphone assemblies 31 are placed side by side, which can effectively extract the plane wave component in the sound signal, improve the accuracy of the sound signal extraction by the microphone assembly 31, and thus improve the noise reduction effect of active noise cancellation.

[0103] In one embodiment, the distance between at least two sets of microphone assemblies 31 is greater than 10cm.

[0104] The microphone assembly 31 is evenly distributed horizontally on the inner wall surface. Since active noise cancellation mainly reduces noise at frequencies around 3500Hz and below, according to c=λf, the sound wave wavelength is 9.7cm and above. The specific spacing needs to be determined in experimental testing and is not specifically limited here.

[0105] In this embodiment, the distance between at least two sets of microphone components 31 is greater than 10cm, which can pick up the sound signals in the air duct 33 as comprehensively as possible and improve the noise reduction effect of active noise cancellation.

[0106] In one embodiment, the distance between the microphone assembly 31 and the speaker 32 is greater than 18 cm.

[0107] Since the microphone assembly 31 is used to pick up noise from the fan assembly 34, and the speaker 32 is used to emit a counter-signal to cancel out the noise, if the microphone assembly 31 and the speaker 32 are too close, the counter-signal emitted by the speaker 32 will be picked up by the microphone assembly 31, affecting the accuracy of the microphone assembly 31 in picking up noise, and thus affecting the noise reduction effect of active noise cancellation. The specific spacing needs to be determined in experimental testing and is not specifically limited here.

[0108] In this embodiment, the distance between the microphone assembly 31 and the speaker 32 is greater than 18cm, which satisfies coherence while preventing mutual interference and avoiding affecting the accuracy of noise pickup by the microphone assembly 31.

[0109] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A microphone assembly for active noise cancellation, characterized in that, The microphone assembly for active noise cancellation includes: a microphone and a flow guide cover, wherein the flow guide cover is disposed opposite to the pickup surface of the microphone; There is a gap for sound pickup between the flow guide cover and the sound pickup surface, and the gap communicates with the sound pickup hole of the microphone; The flow guide cover is provided with a rotating shaft, the microphone pickup surface is provided with a support, the support forms a receiving cavity, and the rotating shaft is inserted into the receiving cavity; the side of the flow guide cover opposite to the gap is provided with an oil stain cleaning device; When the flow guide cover rotates around the rotation axis, the oil stain cleaning device rotates with the flow guide cover to clean the oil stains in the gap; The side of the flow guide cover away from the sound pickup surface has a raised structure.

2. The microphone assembly for active noise cancellation as described in claim 1, characterized in that, The gap gradually increases along the central axis of the flow guide cover; And / or, the area of ​​the flow guide cover is smaller than the area of ​​the sound pickup surface; And / or, the side of the flow guide cover away from the sound pickup surface protrudes; And / or, the roughness of the side of the flow guide cap away from the sound pickup surface is less than the roughness threshold; And / or, the microphone assembly is oval in shape.

3. The microphone assembly for active noise cancellation as described in claim 1, characterized in that, The inner wall of the pickup hole is provided with a first sound insulation component; And / or, a protective film is provided at the opening of the pickup hole near the gap; the protective film includes at least one of the following: a waterproof film, a breathable film, and a waterproof and breathable film; And / or, the microphone includes a sound pressure sensor, the sound pressure sensor is provided with a second sound insulation component, and the sound inlet of the sound pressure sensor is connected to the pickup hole.

4. The microphone assembly for active noise cancellation as described in claim 3, characterized in that, The gap between the flow guide cover and the sound pickup surface is in the range of 0.2mm-1mm; And / or, the protrusion height of the protrusion structure is greater than 2 mm; And / or, the thickness of the first sound insulation component is greater than 1 mm.

5. A range hood, characterized in that, The range hood includes: a speaker, an air duct, and a microphone assembly for active noise cancellation as described in any one of claims 1-4; the microphone assembly and the speaker are disposed on the inner wall of the air duct.

6. The range hood as described in claim 5, characterized in that, The range hood also includes a fan assembly; the fan assembly and the air duct are connected by a flexible pipe.

7. The range hood as described in claim 6, characterized in that, The range hood also includes: a lifting push rod; the air duct includes: a lifting cavity and a smoke collection cavity; The lifting push rod connects the lifting cavity and the smoke collection cavity; the lifting push rod is used to control the lifting height of the lifting cavity.

8. The range hood as described in any one of claims 5-7, characterized in that, The range hood includes at least two sets of microphone assemblies, which are placed side by side. The distance between the at least two sets of microphone assemblies is greater than 10cm; And / or, the distance between the microphone assembly and the speaker is greater than 18cm.

Images