CN220065174U - Active noise reduction cloth bellows and ventilation system - Google Patents
Active noise reduction cloth bellows and ventilation system Download PDFInfo
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- CN220065174U CN220065174U CN202320026948.9U CN202320026948U CN220065174U CN 220065174 U CN220065174 U CN 220065174U CN 202320026948 U CN202320026948 U CN 202320026948U CN 220065174 U CN220065174 U CN 220065174U
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- 230000009467 reduction Effects 0.000 title claims abstract description 38
- 238000009423 ventilation Methods 0.000 title claims abstract description 33
- 239000004744 fabric Substances 0.000 title claims description 32
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 26
- 238000005192 partition Methods 0.000 claims description 20
- 239000000463 material Substances 0.000 claims description 3
- 238000009792 diffusion process Methods 0.000 claims 2
- 238000010521 absorption reaction Methods 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 9
- 238000000034 method Methods 0.000 abstract description 6
- 239000011358 absorbing material Substances 0.000 description 5
- 239000006185 dispersion Substances 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000008030 elimination Effects 0.000 description 2
- 238000003379 elimination reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000005236 sound signal Effects 0.000 description 2
- 229920000742 Cotton Polymers 0.000 description 1
- 239000012814 acoustic material Substances 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000009323 psychological health Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Abstract
An active noise reduction air distribution box and a ventilation system comprise an air distribution box body, a reference microphone, an error microphone, a controller and a secondary sound source, wherein the reference microphone is connected with the secondary sound source through the controller and is used for converting an upstream noise signal into an opposite noise signal with the waveform opposite to that of the upstream noise signal; the secondary sound source is arranged at the downstream section of the air flow in the air distribution box body and is used for outputting reverse noise according to the reverse noise signal, the error microphone detects the sound wave signal remained after the noise is eliminated at the downstream section, the controller outputs a compensation signal after the residual sound wave signal is detected, and the compensation signal outputs corrected reverse noise through the secondary sound source. According to the method, the reverse noise with the waveform opposite to that of the upstream noise signal is output at the downstream of the air in the air box according to the upstream noise signal, and the noise in the air is counteracted by the reverse noise, so that the method has a good noise reduction effect on low-frequency noise of a ventilation pipeline system.
Description
Technical Field
The disclosure belongs to the technical field of noise reduction, and particularly relates to an active noise reduction air distribution box and a ventilation system.
Background
The noise of the ventilation pipeline system is one of the main noise in daily life, and is commonly found in pipelines, air inlets and outlets of ship ventilation systems, building air conditioner air inlets and outlets, rail transit air outlets and the like. When the equipment of the ventilation system starts to operate, mechanical noise generated by the equipment can be transmitted outwards through the ventilation pipeline, so that the physiological and psychological health of people is seriously affected. The traditional noise control technology mainly uses a passive control method, and the main principle is that acoustic energy is consumed through the interaction of noise sound waves and acoustic materials or acoustic structures, so that the purpose of noise reduction is achieved. The method has good control effect on middle and high frequency noise, but when low frequency noise is controlled, passive control equipment is generally heavy, large in size and limited in application range.
The tail end of the existing ventilation system generally does not adopt any noise elimination measures or adopts a small amount of passive noise reduction measures, noise is directly transmitted into a room or cabin space, and the noise reduction effect of the passive noise reduction measures is limited under the limited space because the tail end noise is mainly low-frequency sound. Particularly in ship ventilation systems, because the ventilation system ends are relatively close to the noise source, relatively large low frequency noise is generated, thereby affecting the noise level in the cabin.
Disclosure of Invention
In order to solve at least one of the above technical problems, an object of the present disclosure is to provide a device with a good noise reduction effect on low-frequency noise of a ventilation pipeline system, which has a smaller volume of active noise reduction air distribution box compared with a conventional passive noise reduction device.
In order to achieve the purpose of the disclosure, the technical scheme adopted by the disclosure is as follows:
an active noise reduction cloth bellows comprising:
the air distribution box body can be arranged at the air outlet end of the ventilation system;
the reference microphone is arranged on the upstream section of the air flow in the air distribution box body and is used for acquiring an upstream noise signal of upstream noise of the air distribution box body;
the error microphone is arranged at the downstream section of the air flow in the air distribution box body and is used for acquiring a downstream noise signal of downstream noise of the air distribution box body;
the controller is connected with the secondary sound source through the reference microphone and the error microphone, and is used for converting an upstream noise signal into a reference inverse noise signal with the waveform opposite to the upstream noise signal and converting a downstream noise signal into an error inverse noise signal with the waveform opposite to the downstream noise signal;
and the secondary sound source is arranged at the downstream section of the air flow in the air distribution box body and is used for outputting reference reverse noise according to the reference reverse noise signal and outputting error reverse noise according to the error reverse noise signal.
Optionally, the controller includes power, signal amplifier, power amplifier and control module, the power respectively with signal amplifier, control module, power amplifier and secondary sound source are connected, reference microphone, signal amplifier, control module, power amplifier and secondary sound source connect gradually, the error microphone still with signal amplifier connects.
Optionally, the error microphone is installed at an air outlet of the air distribution box body, and the error microphone is directed to the air outlet.
Optionally, a windshield is mounted on both the reference microphone and the error microphone.
Optionally, a sound absorbing material is also installed in the cloth air box body.
Optionally, the cloth bellows body includes box shell, air intake and air outlet, the air intake passes through the inner chamber and the air outlet intercommunication of box shell, be provided with the air flue baffle in the box shell, the air intake sets up on the box shell lateral wall of air flue entry position, the air outlet sets up the air flue exit position on the box shell.
Optionally, the reference microphone is installed at the air inlet position, the secondary sound source is installed at a side surface of the case housing, and the secondary sound source faces the air outlet.
Optionally, a transverse baffle is disposed in the casing, the transverse baffle divides the inner cavity of the casing into a control area and a dispersion area, the air passage baffle is disposed in the dispersion area, the controller and the secondary sound source are disposed in the control area, the secondary sound source is disposed on the transverse baffle in the control area, and the secondary sound source faces the air outlet.
Optionally, an air outlet guide plate is further installed outside the air outlet, the air outlet guide plate is a cone with a concave side surface, and an adjusting knob for adjusting the air outlet is further installed at the center of the circle of the bottom of the air outlet guide plate.
The disclosure also provides a ventilation system, which comprises a ventilation system body, wherein the air outlet end of the ventilation system body is provided with the active noise reduction air distribution box.
According to the method, the upstream noise signal of the upstream noise is obtained through the gas upstream in the air distribution box body by the reference microphone, the reverse noise opposite to the waveform of the upstream noise signal is output in the air distribution box body according to the upstream noise signal, the reverse noise is counteracted with the noise in the air, the error microphone detects the residual sound wave signal after the noise is eliminated in the downstream section, the controller outputs the compensation signal after the residual sound wave signal is detected, the compensation signal outputs the corrected reverse noise through the secondary sound source, the noise at the downstream position of the air distribution box body is gradually reduced after multiple iterations, the good noise reduction effect is achieved, the low-frequency noise of the ventilation pipeline system is well reduced, and compared with a traditional passive noise reduction device, the device has the advantage of small size.
Drawings
The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.
FIG. 1 is a front view of an active noise reduction cloth bellows of the present disclosure;
FIG. 2 is a top view of an active noise reduction cloth bellows of the present disclosure;
FIG. 3 is a schematic diagram of the controller of the present disclosure;
fig. 4 is a control schematic diagram of an active noise reduction bellows of the present disclosure.
Detailed Description
The present disclosure is described in further detail below with reference to the drawings and the embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant content and not limiting of the present disclosure. It should be further noted that, for convenience of description, only a portion relevant to the present disclosure is shown in the drawings.
In addition, embodiments of the present disclosure and features of the embodiments may be combined with each other without conflict. The present disclosure will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.
Referring to fig. 1 and 2, an active noise reduction air distribution box includes:
the air distribution box body 12, the air distribution box body 12 can be arranged at the air outlet end of the ventilation system, and fresh air of the ventilation system can be discharged through the air distribution box body 12 to distribute air or ventilate the indoor space; or the indoor air is discharged to the outside through the cloth bellows body 12. The shape of the cloth air box body 12 can be set according to the field requirement, and the cloth air box body can be square, is convenient to manufacture and install, can also be round, and has large flow area; the cloth bellows body 12 has at least one air flow passage therein, and the cloth bellows body 12 may also have a flow guiding member therein for guiding the wind to a desired spatial position.
A reference microphone 22 mounted on an upstream section of the air flow in the cloth casing body 12 for acquiring an upstream noise signal in the cloth casing body 12; the reference microphone 22 is typically a sound sensor for converting sound into an electronic signal, connecting the reference microphone 22 to the controller 25 through a signal line, and transmitting a noise signal received by the reference microphone 22 to the controller 25; the reference microphone 22 may be installed at the air inlet position of the cloth bellows body 12, or may be installed on the sidewall of the cloth bellows body 12 at the air inlet. To reduce the effect of airflow on microphone pick-up noise, a windshield is mounted on the reference microphone 22.
An error microphone 23, installed at a downstream section of the air flow in the cloth box body 12, for acquiring a downstream noise signal of the downstream noise of the cloth box body 12. The error microphone 23 detects the sound wave signal remained after the noise is eliminated at the downstream section of the air flow in the air distribution box body 12, the control module 29 outputs a compensation signal after the residual sound wave signal is detected, the compensation signal outputs corrected reverse noise through the secondary sound source 24, thereby gradually reducing the noise at the downstream position of the air distribution box body 12 after multiple iterations, achieving good noise reduction effect, one error microphone 23 can be arranged, a plurality of error microphones 23 can also be sequentially arranged at the downstream position of the air distribution box body 12, and the error microphone 23 is generally arranged at the position of the secondary sound source 24 or the downstream position of the secondary sound source 24. To reduce the effect of airflow on microphone pick-up noise, a windshield is mounted on the error microphone 23.
A controller 25, the reference microphone 22 is connected with the secondary sound source 24 through the controller 25, and is used for converting an upstream noise signal into a reference inverse noise signal with a waveform opposite to the upstream noise signal, and converting a downstream noise signal into an error inverse noise signal with a waveform opposite to the downstream noise signal; the controller 25 may be a digital signal processing chip (DSP), such as a TMS320F2812 chip; the controller 25 may also be implemented as a general purpose CPU (Central Processing Unit ), microprocessor, application specific integrated circuit (Application Specific Integrated Circuit, ASIC), or one or more integrated circuits, which may be mounted on the outside of the bellows body 12 or in the bellows body 12. The conversion of the upstream signal to the reverse signal of opposite waveform by the controller 25 is common prior art and does not involve improvements in the control and conversion methods or embedded software.
A secondary sound source 24, the secondary sound source 24 is mounted on the downstream section of the air flow in the air distribution box body 12 and is used for outputting reference inverse noise according to the reference inverse noise signal and outputting error inverse noise according to the error inverse noise signal. The reverse noise signal is sound wave with the same frequency, similar amplitude or the same phase opposite to the noise, and the reverse noise generated by the reverse noise signal is used for neutralizing the noise in the gas, so that noise elimination is realized.
In another embodiment, the error microphone 23 may be mounted at the air outlet of the cloth bellows body 12, with the error microphone directed toward the air outlet. Sound absorbing material is also mounted in the cloth bellows body 12. Because of the problem of the operation efficiency of the active noise reduction algorithm, the suppression effect on high-frequency noise is poor at present. The optimal way is to only acquire the upstream low-frequency noise signal, generate reverse low-frequency noise at the downstream of the gas according to the upstream low-frequency noise signal, only eliminate the low-frequency noise, and eliminate the intermediate-frequency noise and/or the high-frequency noise by the sound absorbing material.
In another embodiment, referring to fig. 3 and 4, the controller 25 includes a power supply 26, a signal amplifier 27, a power amplifier 28, and a control module 29, where the power supply 26 is connected to the reference microphone 23, the signal amplifier 27, the control module 29, the power amplifier 28, and the secondary sound source 24, and the reference microphone 23, the signal amplifier 27, the control module 29, the power amplifier 28, and the secondary sound source 24 are sequentially connected. The reference microphone 22 picks up the pipeline noise signal at the air inlet of the active noise reduction air distribution system and transmits the pipeline noise signal to the signal amplifier 27, the signal amplifier 27 amplifies the collected sound signal and transmits the amplified sound signal to the control module 29, the control module 29 generates a reverse noise signal after processing and calculating, the reverse signal is input to the power amplifier 28 for amplification and then is output by the secondary sound source 24, and the reverse noise generated by the secondary sound source 24 is counteracted with the original noise. The counteracted acoustic signals are picked up by the error microphone 23 at the air outlet and transmitted to the signal amplifier 27, the acoustic signals are amplified by the signal amplifier 27 and transmitted to the control module 29 for further processing, and the signals are transmitted to the secondary sound source 24 after the reverse signals are generated. Therefore, after multiple iterations, the noise at the air outlet is gradually reduced, and a good noise reduction effect is achieved.
In the present disclosure, the control module 29 adopts a system of "two-in and one-out", wherein "two-in" is respectively connected with the reference microphone 22 and the error microphone 23, receives two paths of signals, enters the control module 29, calculates to obtain a secondary sound source 24 signal, and "one-out" is that the secondary sound source signal is transmitted to the power amplifier 28; the power amplifier 28 amplifies the reverse signal generated by the control module 29 and transmits the amplified signal to the secondary sound source 24 for output.
In the present disclosure, the reference microphone 22 and the error microphone 23 may each be a 1/4 inch microphone, and the secondary sound source may be a 6.5 inch speaker. Can be adjusted according to the actual pipeline or the size of the air distribution box body and the noise condition.
In a specific embodiment, the air distribution box body 12 includes a box shell 21, an air inlet 11 and an air outlet 14, and the box shell 21 is set to 500mm×450mm×230mm, and the diameter of the pipeline at the tail end of the ventilation system is phi 100mm. The whole initiative noise reduction air distribution system is of a cuboid structure, and the size of the air distribution box body and the size of the air inlet and outlet can be designed in a targeted manner according to the ventilation quantity, the noise reduction quantity, the cabin and the room space. The inner cavity of the box body shell 21 forms a diffusing area 10, the air inlet 11 can be a cylindrical shell with the diameter phi of 100mm and the length of 50mm, the air inlet 11 is communicated with the air outlet 14 through the inner cavity of the box body shell 21, is arranged at the front part of the box body shell 21 and is welded with the box body shell 21, the box body shell 21 is internally provided with an air passage baffle 13, the air passage baffle 13 forms an air passage with the inner cavity of the air distribution box body 12, and the air inlet 11 is arranged on the side wall of the box body shell 21 at the inlet position of the air passageThe air outlet 14 is arranged at the bottom of the box shell 21 at the outlet position of the air passage, the height of the air passage partition plate 13 is the same as that of the air dispersing area 10, the upper and lower parts of the air passage partition plate 13 are connected with the top and the bottom of the air dispersing area 10 in a welded mode, the space of the box shell 21 of the whole air dispersing area 10 is divided into flow passages in two directions, and the air outlet 14 is arranged as a circular opening with the diameter phi 200m at the bottom of the box shell 21. The sound absorbing material can be attached to the inner wall of the cloth bellows body 12 and both sides of the air passage partition 13, and can absorb the remaining high frequency noise of the ventilation system end entering the inside of the cloth bellows body 12. The sound absorbing material is exemplified by Basoff cotton with a thickness of 10mm and a bulk weight of 10kg/m 3 。
In another embodiment, the reference microphone 22 may be installed at the air inlet 11, it may be installed on the box housing 21, or may be installed at a middle position of the air inlet 11 and connected to the box housing 21 through a bracket, or installed in an air inlet pipeline outside the air inlet 11, and the secondary sound source 24 is installed at a side surface of the box housing 21, and the secondary sound source 24 faces the air outlet 14.
In the present disclosure, the air passage partition 13 may be a C-shaped partition, an air inlet 11 is provided on a side wall of the box 12 on the back of the C-shaped partition, and an air outlet 14 is provided at the bottom of the box 12 in the cavity of the C-shaped partition. The cross section of the air passage partition 13 may be a frame shape with one surface opened, etc., and the secondary sound source 24 is mounted on the side surface of the C-shaped partition, and the sound emission of the secondary sound source 24 faces the inner cavity of the C-shaped partition.
In order to place the controller 25, a transverse partition plate is arranged in the box shell 21, the transverse partition plate divides the inner cavity of the box shell 21 into a control area 20 and a dispersion area 10, the air passage partition plate 13 is arranged in the dispersion area 10, the controller 25 and the secondary sound source 24 are arranged in the control area 20, the secondary sound source 24 is arranged on the transverse partition plate of the control area 20, and the secondary sound source 24 faces the air outlet 14;
that is, one side surface of the inner cavity of the air passage partition plate 13 is provided with an opening, air in the air dispersing area 10 can enter, one end of the air passage partition plate 13 is provided with a secondary sound source 24, sound production of the secondary sound source 24 faces the inner cavity of the air passage partition plate 13, and one end of the air passage partition plate 13 is provided with an air outlet 14. The error microphone 23 may be placed at the edge of the air outlet 14 at the bottom of the ventilation and air-dispersing area 10 and directed to the air outlet 14; the secondary sound source 24 is mounted on the top of the ventilation and air-dispersing area 10 by bolts, is opposite to the air outlet 14 and is concentric with the air outlet 14.
The power supply 26, the signal amplifier 27, the power amplifier 28 and the control module 29 may all be arranged on a transverse partition. The controller 25 may also be provided in a separate mounting box outside the cloth bellows body 12.
The air outlet 14 is also provided with an air outlet guide plate 15, which is generally arranged right below the air outlet 14, the air outlet guide plate 15 is a conical with concave side surface, which plays roles in guiding and dispersing flow, and the bottom center position of the air outlet 14 guide plate is also provided with an adjusting knob 16 for adjusting the air outlet, which plays a role in adjusting the air inlet.
The disclosure also provides a ventilation system, including the ventilation system body, the air-out end of ventilation system body installs the initiative and falls and fall and make an uproar cloth bellows, falls the wind of ventilation system output.
According to simulation test results, the active noise reduction air distribution system has the noise reduction amount of more than 5dB below 500Hz under the condition that the flow velocity in an air inlet pipe is 3 m/s.
In the description of the present specification, reference to the terms "one embodiment/manner," "some embodiments/manner," "example," "a particular example," "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment/manner or example is included in at least one embodiment/manner or example of the utility model. In this specification, the schematic representations of the above terms are not necessarily for the same embodiment/manner or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments/modes or examples. Furthermore, the various embodiments/modes or examples described in this specification and the features of the various embodiments/modes or examples can be combined and combined by persons skilled in the art without contradiction.
Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.
It will be appreciated by those skilled in the art that the above-described embodiments are merely for clarity of illustration of the disclosure, and are not intended to limit the scope of the disclosure. Other variations or modifications will be apparent to persons skilled in the art from the foregoing disclosure, and such variations or modifications are intended to be within the scope of the present disclosure.
Claims (9)
1. An active noise reduction cloth bellows, comprising:
the air distribution box body can be arranged at the air outlet end of the ventilation system;
the reference microphone is arranged on the upstream section of the air flow in the air distribution box body and is used for acquiring an upstream noise signal of upstream noise of the air distribution box body;
the error microphone is arranged at the downstream section of the air flow in the air distribution box body and is used for acquiring a downstream noise signal of downstream noise of the air distribution box body;
the controller is connected with the secondary sound source through the reference microphone and the error microphone, and is used for converting an upstream noise signal into a reference inverse noise signal with the waveform opposite to the upstream noise signal and converting a downstream noise signal into an error inverse noise signal with the waveform opposite to the downstream noise signal;
the secondary sound source is arranged at the downstream section of the air flow in the air distribution box body and is used for outputting reference reverse noise according to the reference reverse noise signal and outputting error reverse noise according to the error reverse noise signal;
and a windshield is arranged on each of the reference microphone and the error microphone.
2. The active noise reduction cloth bellows of claim 1, wherein: the controller comprises a power supply, a signal amplifier, a power amplifier and a control module, wherein the power supply is respectively connected with the signal amplifier, the control module, the power amplifier and the secondary sound source, the reference microphone, the signal amplifier, the control module, the power amplifier and the secondary sound source are sequentially connected, and the error microphone is also connected with the signal amplifier.
3. The active noise reduction cloth bellows of claim 2, wherein: the error microphone is arranged at the air outlet of the air distribution box body, and the error microphone points to the air outlet.
4. The active noise reduction cloth bellows of claim 1, wherein: and sound absorption materials are also arranged in the air distribution box body.
5. The active noise reduction cloth bellows of claim 1, wherein: the air distribution box comprises a box body, an air inlet and an air outlet, wherein the air inlet is communicated with the air outlet through an inner cavity of the box body, an air passage partition plate is arranged in the box body, the air inlet is arranged on the side wall of the box body at the inlet position of the air passage, and the air outlet is arranged on the box body at the outlet position of the air passage.
6. The active noise reduction cloth bellows of claim 5, wherein: the reference microphone is arranged at the air inlet position, the secondary sound source is arranged on the side face of the box body shell, and the secondary sound source faces the air outlet.
7. The active noise reduction cloth bellows of claim 5, wherein: be provided with horizontal baffle in the box shell, horizontal baffle will the inner chamber of box shell is cut apart into control district and diffusion district, the air flue baffle sets up in the diffusion district, the controller with secondary sound source sets up in the control district, just secondary sound source sets up in the control district on the horizontal baffle, just secondary sound source faces the air outlet.
8. The active noise reduction cloth bellows of claim 5, wherein: the air outlet is characterized in that an air outlet guide plate is further arranged outside the air outlet, the air outlet guide plate is a conical body with a concave side surface, and an adjusting knob for adjusting the air outlet is further arranged at the center of the circle of the bottom of the air outlet guide plate.
9. A ventilation system, characterized by: comprising a ventilation system body, the air outlet end of the ventilation system body is provided with the active noise reduction air distribution box as claimed in any one of claims 1 to 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320026948.9U CN220065174U (en) | 2023-01-05 | 2023-01-05 | Active noise reduction cloth bellows and ventilation system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320026948.9U CN220065174U (en) | 2023-01-05 | 2023-01-05 | Active noise reduction cloth bellows and ventilation system |
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| Publication Number | Publication Date |
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| CN220065174U true CN220065174U (en) | 2023-11-21 |
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| CN202320026948.9U Active CN220065174U (en) | 2023-01-05 | 2023-01-05 | Active noise reduction cloth bellows and ventilation system |
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2023
- 2023-01-05 CN CN202320026948.9U patent/CN220065174U/en active Active
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