CN203286197U - Active-passive composite silencer for ventilation pipeline - Google Patents
Active-passive composite silencer for ventilation pipeline Download PDFInfo
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- CN203286197U CN203286197U CN2013202728758U CN201320272875U CN203286197U CN 203286197 U CN203286197 U CN 203286197U CN 2013202728758 U CN2013202728758 U CN 2013202728758U CN 201320272875 U CN201320272875 U CN 201320272875U CN 203286197 U CN203286197 U CN 203286197U
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Abstract
The utility model relates to an active-passive composite silencer for a ventilation pipeline. The active-passive composite silencer comprises an active silencer, a passive silencer and a reference microphone. The active silencer comprises a first outer shell, an inner pipe section, a loudspeaker unit, an error microphone and a loudspeaker power amplifier board clamp. The first outer shell comprises a sealing cover and a shell body. The sealing cover is of a board-shaped structure with a central hole. The shell body is of a barrel-shaped structure with a hole in the center position of the bottom. One end of the inner pipe section penetrates through the central hole of the sealing cover and is fixed on the sealing cover. The other end of the inner pipe section is embedded into the hole in the center of the shell body. The sealing cover is arranged on the top of the shell body. The loudspeaker unit, the error microphone and the loudspeaker power amplifier board clamp are respectively arranged on the periphery of the inner pipe section. An annular flange is arranged on the side of the inner pipe section. The pipe wall of the inner pipe section 4 corresponding to the mounting positions of the loudspeaker unit and the error microphone is provided with a plurality penetrating holes. The pipe wall of an inner penetrating hole pipe section is provided with a plurality penetrating holes. The passive silencer comprises a second outer shell, the inner penetrating hole pipe section and sound absorption materials.
Description
Technical field
The utility model relates to field of acoustics, the main passive composite muffler of a kind of air pipeline of special design.
Background technique
The air pipeline System noise is common noise source in life, such as central air-conditioning system exhaust outlet, ship's ventilating system inlet/outlet air mouth radiated sound etc., this noise has caused pollution to indoor human settlement, to people's physiology, mental health, will have a negative impact.Although use passive silencing apparatus can effectively suppress the medium-high frequency radiated noise, its residual low-frequency noise energy is still remarkable.For effectively suppressing low-frequency noise, traditional passive noise elimination technique generally has larger volume and the higher pressure loss, and its Practical significance is very limited.Therefore, need further to suppress by means of Technique of Active Noise Control the residual low frequency radiation noise of the air pipeline system mouth of pipe.
Active noise control using is a kind of active noise control technique based on sound wave coherent addition principle, proposed in its patent US2043416 by P.Lueg the earliest, its basic principle is introduced secondary sound source and is utilized it to send identical with initial noise amplitude but single spin-echo " antinoise " in sound field, make initial noise obtain relevant the counteracting, thereby reach the purpose of noise suppression.Compare with the passive noise-reduction method of tradition, the Technique of Active Noise Control main advantage is and can obtains better low frequency noise reduction with less volume.Along with the raising of people's living standard, the low-frequency noise pollution problem is day by day remarkable, and the practical demand of Technique of Active Noise Control is day by day urgent.On the other hand, through the development of last 100 years, especially along with the leap of nearly decades of Digital Signal Processing, Technique of Active Noise Control is increasingly mature, and its practicalization is just progressively accelerated.
Pipe-line system is the typical occasion of Active noise control using application,, for the low-frequency noise below the pipeline cut-off frequency, uses single loudspeaker effectively to it, to suppress.Known pipeline active silencer patent is more common in engine exhaust system, such as CN1126525A, CN101555818A, CN102808681 etc. at present.
Initial noise signal in pipeline active noise control system general using microphone pickup tube, and send antinoise by secondary sound source and offset, namely microphone and secondary sound source need to interact with the interior sound field of pipe.For realizing the coupling of sound field, microphone and secondary sound source place air should with the pipe in conducting, this means that there is certain discontinuity in this place's inner-walls of duct.When the inner air tube flow velocity is higher, thereby the air-flow of this discontinuous boundary will be disturbed and excite quadratic noise, have a strong impact on soundproof effect.Therefore, how to guarantee microphone and secondary sound source place air-flow under high flow rate stationarity, to reduce exciting of quadratic noise be the subject matter that air pipeline system active noise elimination technique faces.
The model utility content
The purpose of this utility model is to overcome the existing poor defect of ventilation pipeline silencer low-frequency effect, thereby a kind of adaptation high altitude stream speed, the main passive composite muffler of the significant air pipeline of low frequency soundproof effect are provided.
To achieve these goals, the utility model provides a kind of air pipeline with main passive composite muffler, comprises active silencer 1, passive silencing apparatus 13 and with reference to microphone 17; Wherein,
Described active silencer 1 comprises the first shell, interior pipeline section 4, loudspeaker unit 5, error microphone 6 and power of loudspeaker amplifier integrated circuit board 7; Described the first shell comprises capping 2 and housing 3; The platy structure of perforate centered by described capping 2, described housing 3 is the barrel-like structure of bottom centre position perforate, one end of described interior pipeline section 4 passes the hole at described capping 2 centers and is fixed in described capping 2, the other end of described interior pipeline section 4 embeds the hole that is arranged in described housing 3 centers, and described capping 2 is installed to the top of described housing 3; Be separately installed with described loudspeaker unit 5, error microphone 6 and power of loudspeaker amplifier integrated circuit board 7 around described interior pipeline section 4, wherein the output interface of power of loudspeaker amplifier integrated circuit board 7 is connected with described loudspeaker unit 5, and the output interface of its signal input interface, power interface and error microphone 6 is drawn by the electric coupler 8 that is installed on described housing 3;
Have on the side of described interior pipeline section 4 be used to the annular flange flange that described loudspeaker unit 5 is installed, there are a plurality of perforation in the tube wall 9 of the described interior pipeline section 4 that described loudspeaker unit 5 and described error microphone 6 installed positions are corresponding; Also there are a plurality of perforation on the tube wall of described interior perforation pipeline section 16;
Described passive silencing apparatus 13 comprises second housing 14, interior perforation pipeline section 16 and sound-absorbing material 15, described second housing 14 is wrapped in outside described interior perforation pipeline section 16, described sound-absorbing material 15 is filled between the two, describedly with reference to microphone 17, be installed in described sound-absorbing material 15, its axial position is at the end of described interior perforation pipeline section 16 away from described active silencer 1.
In technique scheme, described loudspeaker unit 5, error microphone 6, power of loudspeaker amplifier integrated circuit board 7 are installed along the circumferential diverse location of described interior pipeline section 4, and its circumferential angle intervals is 90 °.
In technique scheme, the mounting point of described error microphone 6 is in the downstream sound field of described loudspeaker unit 5.
In technique scheme, the outside of described capping 2 also is equipped with first flange 11 that is threaded hole, the center hole of described the first flange 11 is communicated with described interior pipeline section 4, and by this first flange 11, an end of the interior perforation pipeline section 16 in described passive silencing apparatus 13 is connected with described capping 2.
In technique scheme, the outside of described housing 3 bottom surfaces also is equipped with another and is threaded second flange 11 in hole, the center hole of described the second flange 11 is communicated with described interior pipeline section 4, by this second flange 11, and the downstream pipeline realization of ventilation system and being connected of described housing 3.
In technique scheme, in the joint of described capping 2 and described housing 3 and in the joint of described interior pipeline section 4 and described housing 3, all use rubber pad 10 to seal.
In technique scheme, the diameter of the perforation on the tube wall 9 of described interior pipeline section 4 is 2mm, and punching rate is more than 25%; The diameter of the perforation on the tube wall of described interior perforation pipeline section 16 is 2mm, and punching rate is more than 25%.
In technique scheme, at the inboard sound-absorbing material 12 that attaches for the back cavity radiated sound that absorbs described loudspeaker unit 5 of described housing 3.
In technique scheme, the two ends of described interior perforation pipeline section 16 also include prolonged section, do not have perforation on described prolonged section, and passive muffler flange 18 wherein is installed on the prolonged section of an end,, by this flange 18, realize being connected of upstream of described interior perforation pipeline section 16 and ventilation system.
In technique scheme, describedly with reference to microphone 17, by the mounting hole that extends to interior perforation pipeline section 16 by described second housing 14, it is fixed.
The utility model has the advantage of:
Can reach higher low frequency acoustic attenuation performance with less muffler volume and the pressure loss, can tolerate higher air velocity simultaneously.
Description of drawings
Fig. 1 is the front section view of air pipeline of the present utility model with main passive composite muffler;
Fig. 2 is that air pipeline of the present utility model is looked sectional view with the left side of the active silencer in main passive composite muffler;
Fig. 3 is the active silencer cut-away view of air pipeline of the present utility model in main passive composite muffler;
Fig. 4 is the overall appearance figure of air pipeline of the present utility model with main passive composite muffler.
The accompanying drawing sign
1, active silencer 2, the capping of active silencer shell
3, pipeline section in active silencer case body 4, active silencer
5, loudspeaker unit 6, error microphone
7, power of loudspeaker amplifier integrated circuit board 8, electric coupler
9, active silencer perforation tube wall 10, rubber pad
11, active silencer flange 12, sound-absorbing material layer
13, passive silencing apparatus 14, passive muffler shell
15, perforated pipe in passive silencing apparatus sound-absorbing material 16, passive silencing apparatus
17, with reference to microphone 18, passive muffler flange
Embodiment
Now the utility model will be further described by reference to the accompanying drawings.
With reference to figure 1, air pipeline of the present utility model comprises active silencer 1, passive silencing apparatus 13 with main passive composite muffler and with reference to microphone 17; Wherein, described active silencer 1 comprises the first shell, interior pipeline section 4, loudspeaker unit 5, error microphone 6 and power of loudspeaker amplifier integrated circuit board 7; Described the first shell comprises capping 2 and housing 3; The platy structure of perforate centered by described capping 2, described housing 3 is the barrel-like structure of bottom centre position perforate, one end of described interior pipeline section 4 passes the hole at described capping 2 centers and is fixed in described capping 2, the other end of described interior pipeline section 4 embeds the hole that is arranged in described housing 3 centers, and described capping 2 is installed to the top of described housing 3; Be separately installed with described loudspeaker unit 5, error microphone 6 and power of loudspeaker amplifier integrated circuit board 7 around described interior pipeline section 4, wherein the output interface of power of loudspeaker amplifier integrated circuit board 7 is connected with loudspeaker unit 5, and the output interface of its signal input interface, power interface and error microphone 6 is drawn by the electric coupler 8 that is installed on housing 3; Described passive silencing apparatus 13 comprises second housing 14, interior perforation pipeline section 16 and sound-absorbing material 15, described second housing 14 is wrapped in outside described interior perforation pipeline section 16, described sound-absorbing material 15 is filled between the two, one end of described interior perforation pipeline section 16 is connected with capping 2, and the outside of its other end is equipped with described with reference to microphone 17.
Below all parts of the passive composite muffler of master of the present utility model is described further.
In the present embodiment, described capping 2 is a plectane, and the perforate of its central position is a circular hole, and the diameter of this circular hole is identical with the external diameter of described interior pipeline section 4.The outside of described capping 2 also is equipped with a flange 11 that is threaded hole, and the center hole of described flange 11 is communicated with described interior pipeline section 4, and by this flange 11, an end of the interior perforation pipeline section 16 in passive silencing apparatus is connected with capping 2.In other embodiments, described capping 2 can be also the plate of other shapes, and the perforate of its central position can be also other shapes, but should be consistent with pipe section.
In the present embodiment, described housing 3 is opened round-meshed drum-shaped structure for the bottom center position, and the diameter of this circular hole is identical with the external diameter of described interior pipeline section 4.The outside of described housing 3 bottom surfaces also is equipped with a flange 11 that is threaded hole, and the center hole of described flange 11 is communicated with described interior pipeline section 4, and by this flange 11, the downstream pipeline of ventilation system is realized and being communicated with of described housing 3.In other embodiments, described housing 3 can be also the bucket of other shapes, and the perforate of its bottom center position can be also other shapes, but should be consistent with pipe section.
Be connected by screw the combination that realizes between the two between described capping 2 and housing 3, as a kind of preferred implementation, in the present embodiment, for guaranteeing tightness, in the joint of described capping 2 and described housing 3 and in the joint of described interior pipeline section 4 and described housing 3, all use rubber pad 10 to seal.
As shown in Figure 2, in the present embodiment, described interior pipeline section 4 is the drum-shaped of a both ends open, have annular flange flange on its side, described loudspeaker unit 5 is installed on this annular flange portion, the back cavity that the active silencer shell that consists of described capping 2 and housing 3 and the cavity between described interior pipeline section 4 have formed described loudspeaker unit 5; 7 of described error microphone 6, power of loudspeaker amplifier integrated circuit board are fixed on described interior pipeline section 4 by support separately respectively.As a kind of preferred implementation, as shown in Figure 2, in the present embodiment, for taking full advantage of space, reducing the silencing apparatus overall volume, loudspeaker unit 5, error microphone 6, power of loudspeaker amplifier integrated circuit board 7 are installed along the circumferential diverse location of interior pipeline section 4, and its circumferential angle intervals is 90 °.Simultaneously, loudspeaker unit 5 and error microphone 6 are installed on interior pipeline section 4 diverse location vertically, and namely error microphone 6 should be in the downstream sound field of loudspeaker unit 5, thereby guarantees effective inhibition of downstream pipeline noise.
As shown in Figure 3, there is the perforation of high density, small aperture in the tube wall 9 of the interior pipeline section 4 that described loudspeaker unit 5 and described error microphone 6 installed positions are corresponding, its objective is when realizing entrant sound the air-flow in pipeline is carried out water conservancy diversion, the quadratic noise that inhibition is given birth to by the high-speed air flow movable property, guarantee soundproof effect.In the present embodiment, the diameter in the hole on described tube wall 9 is 2mm, and punching rate is 25%.In other embodiments, the diameter of perforation and punching rate can be carried out actual adjustment according to wind speed in pipe.
In the present embodiment, described loudspeaker unit 5 adopts 4 inches loudspeaker units, and described error microphone 6 adopts 1/2 inch error microphone.
As a kind of preferred implementation, in the present embodiment, at the inboard sound-absorbing material 12 that attaches of described housing 3, to absorb the back cavity radiated sound of loudspeaker unit 5.
There is the perforation of high density, small aperture on the tube wall of described interior perforation pipeline section 16, its objective is when realizing entrant sound the air-flow in pipeline is carried out water conservancy diversion, suppress the quadratic noise of by the high-speed air flow movable property, being given birth to, guarantee soundproof effect.In the present embodiment, the diameter of the perforation on the tube wall of described interior perforation pipeline section 16 is 2mm, and punching rate is 25%.In other embodiments, the diameter of perforation and punching rate can be carried out actual adjustment according to wind speed in pipe.The two ends of described interior perforation pipeline section 16 also include prolonged section, do not have perforation on described prolonged section, passive muffler flange 18 wherein is installed on the prolonged section of an end, and by this flange 18, in realizing, perforation pipeline section 16(is passive silencing apparatus 13) with being connected of the upstream of ventilation system.
The described original noise that is used for picking up upstream with reference to microphone 17, coordinate described active silencer 1 to complete the inhibition of downstream pipeline low frequency random noise energy.In the present embodiment, preferentially select 1/2 cun microphone with error microphone 6 same models with reference to microphone 17, and by the mounting hole that is extended to interior perforation pipeline section 16 by second housing 14, it is fixed.
Fig. 4 is in the present embodiment, the air pipeline of the present utility model overall schematic of main passive composite muffler, and described silencing apparatus integral body is cylindrical, and its outside dimension is Φ 300mm * 600mm, the ventilation system pipeline of corresponding Φ 100mm.
The passive composite muffler of the master that the present embodiment provides both can inserted mode be installed in the ventilation system pipeline, the pipeline in downstream, insertion point was controlled, and also can directly be installed on the inlet/outlet air mouth, directly suppress mouth of pipe radiated noise.
While using the present embodiment to lead passive composite sound damping, should directly connect the input end of peripheral control unit with reference to microphone 17 outputs, and by electric coupler 8, error microphone 6 outputs, 7 inputs of loudspeaker power board are connected respectively another input end and the output terminal of external control system, provide power supply by 8 pairs of loudspeaker power boards 7 of electric coupler simultaneously.Its workflow is, thereby the initial noise in upstream that peripheral control unit picks up reference microphone 17 carries out filtering, produces control signal, and with its input loudspeaker power board 7, drive loudspeaker unit 5 and send the antinoise counteracting that is concerned with.Simultaneously, in peripheral control unit, reply is offset by the antinoise signal that loudspeaker unit 5 microphone 17 that send, referenced picks up.Error microphone 6 is used for off-line design or online adjustment of above-mentioned wave filter, with the filtering that correctly realizes the antinoise signal, calculates.
Measured result shows, airspeed is not more than under the condition of 20m/s in pipe, and this embodiment not only can effectively eliminate blower fan and rotate the line spectrum noise of excitation, the stochastic flow noise that also can decay and produce at bend pipe, valve place, and effective noise elimination frequency band can reach 20～8kHz.
It should be noted last that, above embodiment is only unrestricted in order to the technical solution of the utility model to be described.Although with reference to embodiment, the utility model is had been described in detail, those of ordinary skill in the art is to be understood that, the technical solution of the utility model is modified or is equal to replacement, do not break away from the spirit and scope of technical solutions of the utility model, it all should be encompassed in the middle of claim scope of the present utility model.
Claims (10)
1. an air pipeline, with main passive composite muffler, is characterized in that, comprises active silencer (1), passive silencing apparatus (13) and with reference to microphone (17); Wherein,
Described active silencer (1) comprises the first shell, interior pipeline section (4), loudspeaker unit (5), error microphone (6) and power of loudspeaker amplifier integrated circuit board (7); Described the first shell comprises capping (2) and housing (3); The platy structure of perforate centered by described capping (2), described housing (3) is the barrel-like structure of bottom centre position perforate, one end of described interior pipeline section (4) passes the hole at described capping (2) center and is fixed in described capping (2), the other end of described interior pipeline section (4) embeds the hole that is arranged in described housing (3) center, and described capping (2) is installed to the top of described housing (3); Be separately installed with described loudspeaker unit (5), error microphone (6) and power of loudspeaker amplifier integrated circuit board (7) around described interior pipeline section (4), wherein the output interface of power of loudspeaker amplifier integrated circuit board (7) is connected with described loudspeaker unit (5), and the output interface of its signal input interface, power interface and error microphone (6) is drawn by the electric coupler (8) that is installed on described housing (3);
Have be used to the annular flange flange that described loudspeaker unit (5) are installed on the side of described interior pipeline section (4), there are a plurality of perforation in the tube wall (9) of the described interior pipeline section (4) that described loudspeaker unit (5) and described error microphone 6 installed positions are corresponding; Also there are a plurality of perforation on the tube wall of described interior perforation pipeline section (16);
Described passive silencing apparatus (13) comprises second housing (14), interior perforation pipeline section (16) and sound-absorbing material (15), described second housing (14) is wrapped in outside described interior perforation pipeline section (16), described sound-absorbing material (15) is filled between the two, describedly with reference to microphone (17), be installed in described sound-absorbing material (15), its axial position is at the end of described interior perforation pipeline section (16) away from described active silencer (1).
2. air pipeline use according to claim 1 is led passive composite muffler, it is characterized in that, described loudspeaker unit (5), error microphone (6), power of loudspeaker amplifier integrated circuit board (7) are installed along the circumferential diverse location of described interior pipeline section (4), and its circumferential angle intervals is 90 °.
3. air pipeline according to claim 1, with main passive composite muffler, is characterized in that, the mounting point of described error microphone (6) is in the downstream sound field of described loudspeaker unit (5).
4. air pipeline use according to claim 1 is led passive composite muffler, it is characterized in that, the outside of described capping (2) also is equipped with first flange (11) that is threaded hole, the center hole of described the first flange (11) is communicated with described interior pipeline section (4), by this first flange (11), an end of the interior perforation pipeline section (16) in described passive silencing apparatus (13) is connected with described capping (2).
5. air pipeline use according to claim 1 is led passive composite muffler, it is characterized in that, the outside of described housing (3) bottom surface also is equipped with another and is threaded second flange (11) in hole, the center hole of described the second flange (11) is communicated with described interior pipeline section (4), by this second flange (11), the downstream pipeline realization of ventilation system and being connected of described housing (3).
6. air pipeline use according to claim 1 is led passive composite muffler, it is characterized in that, in the joint of described capping (2) and described housing (3) and in the joint of described interior pipeline section (4) and described housing (3), all use rubber pad (10) to seal.
7. air pipeline according to claim 1, with main passive composite muffler, is characterized in that, the diameter of the perforation on the tube wall (9) of described interior pipeline section (4) is 2mm, and punching rate is more than 25%; The diameter of the perforation on the tube wall of described interior perforation pipeline section (16) is 2mm, and punching rate is more than 25%.
8. air pipeline according to claim 1, with main passive composite muffler, is characterized in that, at the inboard sound-absorbing material (12) that attaches for the back cavity radiated sound that absorbs described loudspeaker unit (5) of described housing (3).
9. air pipeline use according to claim 1 is led passive composite muffler, it is characterized in that, the two ends of described interior perforation pipeline section (16) also include prolonged section, do not have perforation on described prolonged section, passive muffler flange (18) wherein is installed on the prolonged section of an end,, by this flange (18), realize being connected of upstream of described interior perforation pipeline section (16) and ventilation system.
10. air pipeline according to claim 1, with main passive composite muffler, is characterized in that, describedly with reference to microphone (17), by the mounting hole that is extended to interior perforation pipeline section (16) by described second housing (14), it is fixed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013202728758U CN203286197U (en) | 2013-05-17 | 2013-05-17 | Active-passive composite silencer for ventilation pipeline |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2013202728758U CN203286197U (en) | 2013-05-17 | 2013-05-17 | Active-passive composite silencer for ventilation pipeline |
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| CN203286197U true CN203286197U (en) | 2013-11-13 |
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| CN2013202728758U Expired - Lifetime CN203286197U (en) | 2013-05-17 | 2013-05-17 | Active-passive composite silencer for ventilation pipeline |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104165255A (en) * | 2013-05-17 | 2014-11-26 | 中国科学院声学研究所 | Active-passive composite silencer for ventilation pipeline |
| CN104916278A (en) * | 2015-06-01 | 2015-09-16 | 广东肇庆派瑞净化设备有限公司 | Silencer used for adsorption type drier |
| CN105139844A (en) * | 2015-09-17 | 2015-12-09 | 四川迈铁龙科技有限公司 | Composite noise elimination apparatus for ventilation tunnel |
| CN106469551A (en) * | 2015-08-19 | 2017-03-01 | 中兴通讯股份有限公司 | A kind of pipeline noise reduction system and method |
| CN107725487A (en) * | 2017-11-27 | 2018-02-23 | 山东超越数控电子股份有限公司 | A kind of denoising device for fan |
-
2013
- 2013-05-17 CN CN2013202728758U patent/CN203286197U/en not_active Expired - Lifetime
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104165255A (en) * | 2013-05-17 | 2014-11-26 | 中国科学院声学研究所 | Active-passive composite silencer for ventilation pipeline |
| CN104165255B (en) * | 2013-05-17 | 2016-02-03 | 中国科学院声学研究所 | A kind of air pipeline active-passive composite silencing apparatus |
| CN104916278A (en) * | 2015-06-01 | 2015-09-16 | 广东肇庆派瑞净化设备有限公司 | Silencer used for adsorption type drier |
| CN104916278B (en) * | 2015-06-01 | 2018-12-21 | 珠海华信净化设备有限公司 | A kind of silencer for absorption type dryer |
| CN106469551A (en) * | 2015-08-19 | 2017-03-01 | 中兴通讯股份有限公司 | A kind of pipeline noise reduction system and method |
| CN105139844A (en) * | 2015-09-17 | 2015-12-09 | 四川迈铁龙科技有限公司 | Composite noise elimination apparatus for ventilation tunnel |
| CN107725487A (en) * | 2017-11-27 | 2018-02-23 | 山东超越数控电子股份有限公司 | A kind of denoising device for fan |
| CN107725487B (en) * | 2017-11-27 | 2020-01-14 | 山东超越数控电子股份有限公司 | Noise reduction device for fan |
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