CN218328331U - Noise-reducing range hood - Google Patents
Noise-reducing range hood Download PDFInfo
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- CN218328331U CN218328331U CN202222617864.0U CN202222617864U CN218328331U CN 218328331 U CN218328331 U CN 218328331U CN 202222617864 U CN202222617864 U CN 202222617864U CN 218328331 U CN218328331 U CN 218328331U
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Abstract
A noise-reducing range hood comprises: the device comprises a fan, a smoke collecting channel, a smoke discharging channel and an active noise reduction module, wherein the fan is provided with an air inlet and an air outlet; the smoke collecting channel is provided with a smoke inlet and a smoke outlet, and the smoke outlet is positioned at the downstream of the smoke inlet and communicated with the air inlet of the fan along the flow path of the air flow; the smoke exhaust channel is provided with a smoke inlet and a smoke outlet, and the smoke inlet is positioned at the upstream of the smoke outlet and communicated with the air outlet of the fan along the flow path of the airflow; the active noise reduction modules are at least two groups, namely a first noise reduction module and a second noise reduction module: the first noise reduction module and the second noise reduction module are both positioned in the smoke collection channel and are arranged at intervals along the flow path of the airflow; or the first noise reduction module is arranged in the smoke collection channel, and the second noise reduction module is arranged in the smoke discharge channel. Compared with the prior art, the noise reduction effect can be improved.
Description
Technical Field
The utility model belongs to the technical field of kitchen appliance, concretely relates to range hood of making an uproar falls.
Background
The range hood is an important electrical appliance in a kitchen and comprises a shell and a fan arranged in the shell, wherein the shell is provided with an air inlet and an air outlet, negative pressure is generated by rotation of an impeller in the fan, indoor oil smoke is sucked into the shell through the air inlet, and then the oil smoke is discharged out of the room through the air outlet. Because the fan operation of range hood can bring the noise, so reduce range hood noise also is the problem of everybody's unanimous concern.
Active noise reduction means that if two sounds with close or identical frequencies are superimposed to synthesize a sound, their amplitude becomes larger or smaller or constant (i.e. sound wave interference). If two sound waves are identical in frequency and amplitude, but are oppositely biased in phase, the two sound waves are opposite in phase and cancel each other, wherein the sound wave opposite in phase to the noise is called a counter-phase sound wave (or canceling sound wave).
Active noise reduction is taken as a novel noise reduction technology and is also considered to be applied to the range hood for noise reduction. When people actively reduce noise in the range hood, the active noise reduction module is usually placed at the air inlet of the shell to reduce noise of a sound source of the air inlet. Specifically, the structure disclosed in patent application CN202010811753.6, active noise reduction device and method for range hood (application publication No. CN 111899712A), includes a first noise pickup component installed at an air inlet grille at the lower part of the range hood, a second noise pickup component installed on the lower end surface of the range hood or at the center position right below the lower end surface, a speaker component installed below the air inlet grille and above the lower end surface of the range hood, and a controller, wherein a horn of the speaker component faces the front lower part of the range hood, and the first noise pickup component, the second noise pickup component and the speaker component are connected with the controller.
But because range hood is a three-dimensional device, except that the air intake can outwards propagate the noise, range hood's air outlet and fan, wind channel all can produce the noise, and the noise of range hood air outlet directly outwards propagates the people's ear, and the noise in fan and the wind channel then can outwards propagate through the casing to it is not good to lead to the effect of initiatively falling the noise.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the technical problem that to prior art's current situation, a adopt the range hood of making an uproar that falls of technique of making an uproar falls is provided.
The utility model provides a technical scheme that above-mentioned technical problem adopted does: a noise-reducing range hood comprises:
the fan is provided with an air inlet and an air outlet;
the smoke collecting channel is provided with a smoke inlet and a smoke outlet, and the smoke outlet is positioned at the downstream of the smoke inlet and communicated with the air inlet of the fan along the flow path of the air flow;
the smoke exhaust channel is provided with a smoke inlet and a smoke outlet, and the smoke inlet is positioned at the upstream of the smoke outlet and communicated with the air outlet of the fan along the flow path of the airflow;
the active noise reduction module is used for emitting reverse sound waves according to the detected noise so as to offset the noise;
the method is characterized in that:
the active noise reduction modules are at least two groups, namely a first noise reduction module and a second noise reduction module:
the first noise reduction module and the second noise reduction module are both positioned in the smoke collection channel and are arranged at intervals along the flow path of the airflow;
or the like, or a combination thereof,
the first noise reduction module is arranged in the smoke collection channel, and the second noise reduction module is arranged in the smoke exhaust channel.
Preferably, the device also comprises a smoke collecting hood and a fan hood, wherein the smoke collecting hood is hollow inside to form a smoke collecting cavity; the fan cover is arranged above the smoke collecting hood, a fan cavity is formed in the fan cover in a hollow mode, a fan is installed in the fan cavity, the fan cavity is communicated with the smoke collecting cavity to form the smoke collecting channel, and the bottom wall or the front side wall of the smoke collecting cavity is provided with a smoke inlet which is opened to form the smoke collecting channel;
the first noise reduction module is arranged on the smoke collecting hood, and the second noise reduction module is arranged on the fan hood; or the first noise reduction module is alternatively arranged on the smoke collecting hood and the fan hood, and the second noise reduction module is arranged on the smoke exhaust channel.
Furthermore, the fan cover and the smoke collecting cover are arranged at intervals from top to bottom; the smoke collecting channel is formed by the smoke collecting cover, the fan cover and the fan cavity;
the first noise reduction module and the second noise reduction module are respectively arranged on two of the smoke collecting hood, the fan hood and the air duct; or the first noise reduction module is alternatively arranged on the smoke collecting hood, the fan hood and the air duct, and the second noise reduction module is arranged on the smoke exhaust channel. Therefore, the fan cover can be arranged relatively far away from the hearth surface, and the fan in the fan cover can be relatively far away from the user, so that the noise emitted by the fan can be relatively far away from the user; and the arrangement of the first and second noise reduction modules can further reduce noise.
In addition, the first and second noise reduction modules can also be arranged on the smoke collecting hood or the fan hood or the air duct at the same time.
In each of the above solutions, preferably, the active noise reduction module includes:
the sound collector is used for collecting noise signals;
the input end of the controller is connected with the sound collector and is used for generating a noise reduction signal according to the received noise signal;
and the loudspeaker is connected with the output end of the controller and used for sending out reverse sound waves according to the received noise reduction signal so as to counteract noise.
In order to further improve the noise reduction effect, preferably, in a state where the active noise reduction module is located in the smoke collection channel, the sound collector and the speaker are arranged at intervals along the flow path of the airflow, the sound collector is relatively close to the fan, and the speaker is relatively far away from the fan;
and under the condition that the active noise reduction module is positioned in the smoke exhaust channel, the sound collector and the loudspeaker are arranged at intervals along the flow path of the air flow, the sound collector is relatively close to the fan, and the loudspeaker is relatively far away from the fan. Therefore, the sound collector can better collect the noise of a main noise source, namely a fan.
Preferably, in a state where the active noise reduction module is located in the smoke collection channel, the sound emission direction of the speaker is opposite to the flow direction of the corresponding air flow; and under the condition that the active noise reduction module is positioned in the smoke exhaust channel, the sound production direction of the loudspeaker is consistent with the flow direction of the corresponding air flow.
In the above solution, to further improve the noise reduction effect, preferably, at least two speakers in each set of active noise reduction modules are arranged at intervals in the left-right direction.
Preferably, the speakers are provided inside the corresponding channels, or outside the corresponding channels.
Preferably, the channel has a front side wall, the speaker is disposed at the front side of the front side wall and connected to the front side wall, and the sound emission direction of the speaker is backward.
Furthermore, the channel is provided with a first side wall and a second side wall which are oppositely arranged at intervals left and right, the two loudspeakers are symmetrically arranged on the first side wall and the second side wall, and the sound production directions of the two loudspeakers are opposite.
Furthermore, the sound collector in the first noise reduction module is a reference microphone, and the sound collector in the second noise reduction module is an error microphone of the first noise reduction module.
Compared with the prior art, the utility model has the advantages of: through setting up first noise reduction module, the module of making an uproar is fallen to the second, the module of making an uproar is all located the collection cigarette passageway on fan upper reaches to flow path interval arrangement along the air current, or, the collection cigarette passageway on fan upper reaches is located to first noise reduction module, the smoke exhaust passage on fan low reaches is located to the module of making an uproar is fallen to the second noise reduction, thus, first, the module of making an uproar is fallen in the second formation two-stage initiative, can fall the noise of the different positions of range hood and fall in step, the noise reduction effect has been improved, effectively avoid falling the noise because of single position, the not good problem of the overall noise reduction effect that leads to of making an uproar is fallen in other positions.
Drawings
Fig. 1 is a schematic structural diagram of a range hood according to a first embodiment of the present invention;
fig. 2 is a schematic view of a first installation position of an active noise reduction module according to a first embodiment of the present invention;
fig. 3 is a schematic view of a second installation position of an active noise reduction module according to a first embodiment of the present invention;
fig. 4 is a schematic view of a third installation position of the active noise reduction module according to the first embodiment of the present invention;
fig. 5 is a schematic view of a fourth installation position of the active noise reduction module according to the first embodiment of the present invention;
fig. 6 is a schematic diagram of a fifth installation position of the active noise reduction module according to the first embodiment of the present invention;
fig. 7 is a schematic diagram of a sixth installation position of the active noise reduction module according to the first embodiment of the present invention;
fig. 8 is a front view of an active noise reduction module in a central smoke collection channel according to an embodiment of the present invention;
FIG. 9 is a left side view of FIG. 8;
fig. 10 is a control circuit diagram of an active noise reduction module according to a first embodiment of the present invention;
fig. 11 is another control circuit diagram of an active noise reduction module according to an embodiment of the present invention;
fig. 12 is a circuit diagram of another control circuit of an active noise reduction module according to an embodiment of the present invention;
fig. 13 is a front view of an active noise reduction module according to a second embodiment of the present invention;
FIG. 14 is a left side view of FIG. 13;
fig. 15 is a front view of an active noise reduction module according to a third embodiment of the present invention;
fig. 16 is a left side view of fig. 15.
Detailed Description
The present invention will be described in further detail with reference to the following embodiments.
The first embodiment is as follows:
as shown in fig. 1-12, for the first preferred embodiment of the noise reduction range hood of the present invention, the noise reduction range hood includes a fan 1, a smoke collecting channel 2, a smoke discharging channel 3, and an active noise reduction module 4.
The fan 1 has an air inlet 11 and an air outlet 12.
The smoke collecting channel 2 is provided with a smoke inlet 21 and a smoke outlet 22, along the flow path of the air flow, the smoke outlet 22 is positioned at the downstream of the smoke inlet 21 and communicated with the air inlet 11 of the fan 1, and the smoke inlet 21 is communicated with the kitchen space. The smoke collection channel 2 in this embodiment is composed of a smoke collection cover 2a, a fan cover 2b and an air duct 2 c. Wherein, collection petticoat pipe 2a is close to the mesa of top of a kitchen range relatively and sets up, and the inside cavity of collection petticoat pipe 2a forms the collection smoke chamber, and the diapire or the preceding lateral wall of collection smoke chamber have the flue gas entry 21 of uncovered and formation collection cigarette passageway 2. The fan cover 2b is arranged above the smoke collecting cover 2a and is relatively far away from the hearth surface, and a fan cavity is formed in the hollow part of the fan cover 2b so that the fan 1 can be installed in the fan cavity. The air duct 2c extends up and down, is arranged between the smoke collecting cover 2a and the fan cover 2b and is communicated with the smoke collecting cavity and the fan cavity.
The smoke exhaust channel 3 is a smoke exhaust pipe having a smoke inlet 31 and a smoke outlet 32, and along the flow path of the airflow, the smoke inlet 31 is located upstream of the smoke outlet 32 and is communicated with the air outlet 12 of the fan 1. The smoke outlet 32 is in communication with the outdoor environment.
The active noise reduction modules 4 are configured to emit inverse sound waves according to the detected noise to cancel the noise, and there are at least two groups of the active noise reduction modules 4, which are the first noise reduction module 1 and the second noise reduction module 42, respectively, and the installation positions of the first noise reduction module 41 and the second noise reduction module 42 may be one of the following schemes (certainly not limited to the following schemes):
1. as shown in fig. 2, the first noise reduction module 41 is disposed on the smoke collecting hood 2a, and the second noise reduction module 42 is disposed on the air duct 2c;
2. as shown in fig. 3, the first noise reduction module 41 is provided on the smoke collecting hood 2a, and the second noise reduction module 42 is provided on the fan hood 2b;
3. as shown in fig. 4, the first noise reduction module 41 is disposed on the smoke collecting hood 2a, and the second noise reduction module 42 is disposed on the smoke exhaust passage 3;
4. as shown in fig. 5, the first noise reduction module 41 is disposed in the air duct 2c, and the second noise reduction module 42 is disposed in the smoke evacuation channel 3;
5. as shown in fig. 6, the first noise reduction module 41 is disposed on the air duct 2c, and the second noise reduction module 42 is disposed on the fan guard 2b;
6. as shown in fig. 7, the first noise reduction module 41 is provided in the fan guard 2b, and the second noise reduction module 42 is provided in the smoke evacuation duct 3.
In this embodiment, each set of active noise reduction modules 4 includes a sound collector 4a, a controller 4b, and a speaker 4c. The sound collector 4a is a microphone for collecting noise signals. The input end of the controller 4b is connected to the sound collector 4a, and is configured to generate a noise reduction signal according to the received noise signal. The speaker 4c is connected to the output terminal of the controller 4b, and is used for emitting an inverse sound wave according to the received noise reduction signal to cancel the noise. In this embodiment, as shown in fig. 10, each set of active noise reduction modules 4 has its own reference microphone, speaker 4c, and controller 4b. In addition, as shown in fig. 11, one controller 4b may be shared among the groups of active noise reduction modules 4. Further, as shown in fig. 12, the sound collector 4a in the first noise reduction module 41 is a reference microphone, and the sound collector 4a in the second noise reduction module 41 is an error microphone of the first noise reduction module 41, for feeding back the noise reduction effect.
And in the state that the active noise reduction module 4 is located in the smoke collection channel 2, as shown in fig. 8 and 9, the sound collector 4a and the speaker 4c are arranged at intervals along the flow path of the air flow, and the sound collector 4a is relatively close to the fan 1, and the speaker 4c is relatively far away from the fan 1. Namely, the air flow passes through the loudspeaker 4c and the sound collector 4a in sequence and then enters the fan 1. Meanwhile, the sound emission direction of the speaker 4c is downward, opposite to the flow direction of the corresponding air flow. In the embodiment, at least two speakers 4c in each set of active noise reduction modules 4 are arranged at intervals in the left-right direction, and at least two sound collectors 4a are also arranged at intervals in the left-right direction. The loudspeaker 4c and the sound collector 4a are both located in the smoke collection channel 2.
In the state that the active noise reduction module 4 is located in the smoke evacuation channel 3, the sound collector 4a and the speaker 4c are arranged at intervals along the flow path of the air flow, and the sound collector 4a is relatively close to the fan 1 and the speaker 4c is relatively far away from the fan 1. That is, the air flow from the fan 1 passes through the sound collector 4a and the speaker 4c in sequence and is discharged to the outside. Meanwhile, the sound emission direction of the speaker 4c coincides with the flow direction of the corresponding air flow.
Example two:
as shown in fig. 13 and 14, in order to achieve the second preferred embodiment of the noise reduction range hood of the present invention, the present embodiment is basically the same as the first embodiment, except that the speaker 4c is disposed outside the corresponding channel (e.g. the smoke collection channel 2), specifically: the channel has a front side wall, a speaker 4c is arranged in front of the front side wall and connected with the front side wall, and the sound emitting direction of the speaker 4c faces backwards.
Example three:
as shown in fig. 15 and 16, in order to achieve the third preferred embodiment of the noise reduction range hood of the present invention, the present embodiment is basically the same as the first embodiment, except that the speaker 4c is disposed outside the corresponding channel (e.g. the smoke collection channel 2), specifically: the channel is provided with a first side wall and a second side wall which are oppositely arranged at intervals left and right, the two loudspeakers 4c are symmetrically arranged on the first side wall and the second side wall, and the sound production directions of the two loudspeakers 4c are opposite.
Claims (11)
1. A noise-reducing range hood comprises:
the fan (1) is provided with an air inlet (11) and an air outlet (12);
the smoke collecting channel (2) is provided with a smoke inlet (21) and a smoke outlet (22), and the smoke outlet (22) is positioned at the downstream of the smoke inlet (21) and communicated with the air inlet (11) of the fan (1) along the flow path of the air flow;
the smoke exhaust channel (3) is provided with a smoke inlet (31) and a smoke outlet (32), and the smoke inlet (31) is positioned at the upstream of the smoke outlet (32) along the flow path of the airflow and communicated with the air outlet (12) of the fan (1);
the active noise reduction module (4) is used for emitting reverse sound waves according to the detected noise so as to offset the noise;
the method is characterized in that:
the active noise reduction modules (4) are at least two groups, namely a first noise reduction module (41) and a second noise reduction module (42):
the first noise reduction module (41) and the second noise reduction module (42) are both positioned in the smoke collection channel (2) and are arranged at intervals along the flow path of the airflow;
or the like, or a combination thereof,
the first noise reduction module (41) is arranged in the smoke collection channel (2), and the second noise reduction module (42) is arranged in the smoke discharge channel (3).
2. The noise-reducing range hood of claim 1, wherein: the device also comprises a smoke collecting hood (2 a) and a fan hood (2 b), wherein the smoke collecting hood (2 a) is hollow inside to form a smoke collecting cavity; the fan cover (2 b) is arranged above the smoke collecting cover (2 a), a fan cavity is formed in the fan cover in a hollow mode, the fan (1) is installed in the fan cavity, the fan cavity is communicated with the smoke collecting cavity to form the smoke collecting channel (2), and the bottom wall or the front side wall of the smoke collecting cavity is provided with a smoke inlet (21) which is opened to form the smoke collecting channel (2);
the first noise reduction module (41) is arranged on the smoke collecting cover (2 a), and the second noise reduction module (42) is arranged on the fan cover (2 b); or the first noise reduction module (41) is alternatively arranged on the smoke collecting hood (2 a) and the fan cover (2 b), and the second noise reduction module (42) is arranged on the smoke exhaust channel (3).
3. The noise-reducing range hood of claim 2, wherein: the fan cover (2 b) and the smoke collecting cover (2 a) are arranged at intervals from top to bottom; the smoke collecting device also comprises an air duct (2 c) which extends up and down and is arranged between the smoke collecting cover (2 a) and the fan cover (2 b) and communicated with the smoke collecting cavity and the fan cavity, and the smoke collecting channel (2) is formed by the smoke collecting cavity, the fan cavity and the smoke collecting cavity;
the first noise reduction module (41) and the second noise reduction module (42) are respectively arranged on two of the smoke collecting hood (2 a), the fan hood (2 b) and the air duct (2 c); or the first noise reduction module (41) is alternatively arranged on the smoke collecting hood (2 a), the fan hood (2 b) and the air duct (2 c), and the second noise reduction module (42) is arranged on the smoke exhaust channel (3).
4. A noise reducing range hood according to any one of claims 1 to 3, wherein: the active noise reduction module (4) comprises:
the sound collector (4 a) is used for collecting noise signals;
the input end of the controller (4 b) is connected with the sound collector (4 a) and is used for generating a noise reduction signal according to the received noise signal;
and the loudspeaker (4 c) is connected with the output end of the controller (4 b) and is used for sending out reverse sound waves according to the received noise reduction signal so as to counteract the noise.
5. The noise-reducing range hood of claim 4, wherein: in the state that the active noise reduction module (4) is positioned in the smoke collection channel (2), the sound collector (4 a) and the loudspeaker (4 c) are arranged at intervals along the flow path of the airflow, the sound collector (4 a) is relatively close to the fan (1), and the loudspeaker (4 c) is relatively far away from the fan (1);
under the state that the active noise reduction module (4) is positioned in the smoke exhaust channel (3), the sound collector (4 a) and the loudspeaker (4 c) are arranged at intervals along the flow path of the air flow, the sound collector (4 a) is relatively close to the fan (1), and the loudspeaker (4 c) is relatively far away from the fan (1).
6. The noise-reducing range hood according to claim 4, wherein: when the active noise reduction module (4) is positioned in the smoke collection channel (2), the sounding direction of the loudspeaker (4 c) is opposite to the flowing direction of the corresponding airflow; and under the condition that the active noise reduction module (4) is positioned in the smoke exhaust channel (3), the sound production direction of the loudspeaker (4 c) is consistent with the flow direction of the corresponding air flow.
7. The noise-reducing range hood of claim 4, wherein: at least two loudspeakers (4 c) in each group of active noise reduction modules (4) are arranged at intervals along the left-right direction.
8. The noise-reducing range hood of claim 7, wherein: the loudspeaker (4 c) is arranged in the corresponding channel or arranged outside the corresponding channel.
9. The noise-reducing range hood of claim 8, wherein: the channel is provided with a front side wall, the loudspeaker (4 c) is arranged on the front side of the front side wall and connected with the front side wall, and the sound production direction of the loudspeaker (4 c) is backward.
10. The noise-reducing range hood of claim 8, wherein: the channel is provided with a first side wall and a second side wall which are oppositely arranged at intervals left and right, the two loudspeakers (4 c) are symmetrically arranged on the first side wall and the second side wall, and the sound production directions of the two loudspeakers (4 c) are opposite.
11. The noise-reducing range hood of claim 4, wherein: the sound collector (4 a) in the first noise reduction module (41) is a reference microphone, and the sound collector (4 a) in the second noise reduction module (42) is an error microphone of the first noise reduction module (41).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222617864.0U CN218328331U (en) | 2022-09-29 | 2022-09-29 | Noise-reducing range hood |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222617864.0U CN218328331U (en) | 2022-09-29 | 2022-09-29 | Noise-reducing range hood |
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| CN218328331U true CN218328331U (en) | 2023-01-17 |
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| CN202222617864.0U Active CN218328331U (en) | 2022-09-29 | 2022-09-29 | Noise-reducing range hood |
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