CN105575379B - Anechoic room and silencer for it - Google Patents
Anechoic room and silencer for it Download PDFInfo
- Publication number
- CN105575379B CN105575379B CN201510958937.4A CN201510958937A CN105575379B CN 105575379 B CN105575379 B CN 105575379B CN 201510958937 A CN201510958937 A CN 201510958937A CN 105575379 B CN105575379 B CN 105575379B
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- Prior art keywords
- sound absorption
- plate
- sound
- wedge absorber
- noise elimination
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Building Environments (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Abstract
The invention discloses a kind of anechoic room and for its silencer, including noise elimination main body, the noise elimination main body includes the sound absorption plate (1) and wedge absorber (2) being connected along direction of sound propagation, in this way, the sound for the different frequency that noise source issues can be absorbed by the connected sound absorption plate being stacked together and wedge absorber, and noise elimination effect is good.Wherein, compared to wedge absorber, the effect of low-frequency sound absorption for the plate that absorbs sound under condition of equivalent thickness is more preferable, in the case where guaranteeing identical cutoff frequency, can shorten the thickness of noise elimination main body, helps to save space.Therefore, sound absorption effect can be significantly improved compared to exclusive use sound absorption plate or wedge absorber, silencer provided by the invention, obtains excellent free found field, and convenient for safeguarding.
Description
Technical field
The present invention relates to anechoic room experimental systems, and in particular, to a kind of silencer and the anechoic room using the silencer.
Background technique
With the requirement refined to auto NVH, major motor corporation's pay attention to day by day automobile and its examination of power assembly noise
It tests, focuses on the noise of research automobile and its power assembly etc., to further take noise reduction measure, improve vehicle NVH performance.
It is well known that acoustical testing environment is a key factor for influencing the noise fests such as vehicle and its dynamical system.
Anechoic room is a necessary condition for carrying out automobile industry noise fest in a deep going way, and the sound absorption processing of anechoic room is to guarantee that anechoic room is built
At the rear key for obtaining good free found field performance, and in the prior art, the sound absorption with strong acoustical absorptivity is mostly used greatly
Wedge or flat resonance sound-absorbing structure for sheet.Wall surface generally selects the individual wedge absorber structure of installation or suction in anechoic room
Sound slab construction enhances the sound absorption effect at interface, so individually using the suction often for absorbing different frequency noise sound wave
Sound effective value is not it is obvious that therefore providing one kind to take into account wedge absorber and the silencer for the plate that absorbs sound is with positive effect
's.
Summary of the invention
The object of the present invention is to provide a kind of silencer, which can be absorbed the noise sound wave of different frequency, enhancing
Sound absorption effect.
It is a further object to provide a kind of anechoic room, the inner wall of the anechoic room is equipped with the silencer.
To achieve the goals above, the present invention provides a kind of silencer for anechoic room, including noise elimination main body, described to disappear
Sound main body includes the sound absorption plate and wedge absorber being connected along direction of sound propagation.
Optionally, the sound absorption plate includes the first sound absorption plate, which is located at the noise elimination main body most
Close to the side of noise source.
Optionally, the wedge absorber includes the first wedge absorber, and the base portion of first wedge absorber is located at the noise elimination
Main body is closest to the side of noise source.Optionally, the sound absorption plate includes the second sound absorption plate, which is located at
The noise elimination main body is closest to the side of the noise elimination chamber interior walls.
Optionally, the silencer includes sounding board, which is connected to the noise elimination main body close to the one of noise source
Side.
Optionally, the wedge absorber includes the second wedge absorber, and the tip of second wedge absorber and described first inhale
The tip of sound wedge is connected.Optionally, the sound absorption plate includes the first sound absorption plate and the second sound absorption plate, and described first inhales
Sound plate is connected to the base portion of first wedge absorber, and the second sound absorption plate is connected to the base of second wedge absorber
Portion.
Optionally, the silencer includes the mounting plate on the inner wall for installation into the anechoic room, and with it is described
Mounting plate coats the exterior panel of the noise elimination main body jointly, and the exterior panel is formed by entrant sound perforated plate, and the mounting plate is by nothing
Hole steel plate is formed.
Optionally, the junction between the sound absorption plate and the wedge absorber, is provided with connecting plate, the connecting plate
It is formed by entrant sound perforated plate.
In the above-mentioned technical solutions, the sound for the different frequency that noise source issues can be stacked together by being connected
Sound absorption plate and wedge absorber are absorbed, and noise elimination effect is good.Wherein, it compared to wedge absorber, absorbs sound under condition of equivalent thickness flat
The effect of low-frequency sound absorption of plate is more preferable, in the case where guaranteeing identical cutoff frequency, can shorten the thickness of noise elimination main body, facilitate
Save space.Therefore, it can obviously be mentioned compared to exclusive use sound absorption plate or wedge absorber, silencer provided by the invention
High acoustic absorption effect obtains excellent free found field, and convenient for safeguarding.Other features and advantages of the present invention will be in subsequent tool
Body embodiment part is described in detail.
Detailed description of the invention
The drawings are intended to provide a further understanding of the invention, and constitutes part of specification, with following tool
Body embodiment is used to explain the present invention together, but is not construed as limiting the invention.In the accompanying drawings:
Fig. 1 is the silencer of the first combining form provided by the invention.
Fig. 2 is the silencer of second of combining form provided by the invention.
Fig. 3 is the silencer of the third combining form provided by the invention.
Fig. 4 is the silencer of the 4th kind of combining form provided by the invention.
Description of symbols
1 sound absorption 2 wedge absorber of plate
3 mounting plates 11 first sound absorption plate
12 second sound absorption 21 first wedge absorbers of plate
22 second wedge absorbers
Specific embodiment
Below in conjunction with attached drawing, detailed description of the preferred embodiments.It should be understood that this place is retouched
The specific embodiment stated is merely to illustrate and explain the present invention, and is not intended to restrict the invention.
In the present invention, in the absence of explanation to the contrary, the noun of locality used such as " inside and outside " refers to attached drawing respective wheel
It is wide it is inner and outer for.
As shown in Figures 1 to 4, the present invention provides a kind of silencer for anechoic room, and the anechoic room includes along sound
The direction of propagation connected sound absorption plate 1 and wedge absorber 2, in this way, the sound for the different frequency that noise source issues can be connected
Sound absorption plate 1 and wedge absorber 2 absorbed, the two combine after noise elimination effect it is significant.In addition, since sound absorption plate 1 exists
It is more preferable for effect of low-frequency sound absorption compared to wedge absorber 2 under condition of equivalent thickness, it, can be in the case where guaranteeing identical cutoff frequency
The thickness for shortening noise elimination main body facilitates the space for saving anechoic room.Therefore, compared to exclusive use sound absorption plate or sound absorption
Wedge, silencer provided by the invention can significantly improve sound absorption effect, obtain excellent free found field, and convenient for safeguarding.
Wherein, sound absorption plate 1 and wedge absorber 2 can be filled with foamed plastics, soft fibre, glass fiber inside it
The porous materials such as cotton, the impedance that wherein there is wedge absorber 2 acoustic impedance porous material is gradually transitioned into from the characteristic impedance of air,
It can be realized good impedance matching, noise enable efficiently to be absorbed, and absorbing sound plate 1 then is plate structure, due to
Integral thickness is consistent, therefore can have better effect of low-frequency sound absorption with 2 condition of equivalent thickness of wedge absorber.
As shown in Fig. 1,2 and 4, i.e., in first, second and the 4th in combination, sound absorption plate 1 includes that the first sound absorption is flat
Plate 11, in a preferred embodiment of the invention, the first sound absorption plate 11 are located at noise elimination main body closest to the side of noise source,
That is, noise source is absorbed by the first sound absorption plate 11 first, in this way, installing since the first sound absorption plate 11 is closer to noise source
When to anechoic room, the first sound absorption plate 11 of adjacent silencer can mutually splice integral noise elimination inner wall, to be effectively reduced
Wedge absorber 2 is stained, and is also convenient for indoors safeguarding silencer.
As also shown in fig. 3, i.e., in third combination, wedge absorber 2 includes the first wedge absorber 21, it is preferable that should
The base portion of first wedge absorber 21 is located at noise elimination main body 1 closest to the side of noise source, well known, wedge absorber 2 by tip and
Base portion composition, tip are smaller relative to the sectional area of base portion.And select the biggish base portion of sectional area as closest to noise source
Outermost layer, when being installed to anechoic room, the base portion of the first wedge absorber 21 of adjacent silencer can also mutually splice integral
Noise elimination inner wall, consequently facilitating being safeguarded indoors to silencer.In addition base portion enables to this to fall close to the arrangement of noise source
The wedge absorber 2 set preferably absorbs the sound absorption with the reflected acoustic wave of direction of sound propagation phase anti-spread, to further be promoted
Sound absorption effect.
In addition, as shown in Figures 1 to 4, i.e., in first and the 4th in combination, sound absorption plate 1 includes the second sound absorption plate
12, which is located at noise elimination main body 1 closest to the side of noise elimination chamber interior walls, that is, inhales thickness biggish second
Sound plate 12 is installed on the inner wall of anechoic room, can be improved the installation rigidity and intensity of silencer, guarantees the stability of installation.
It in addition, i.e., can be in combination as shown in Figure 1, Figure 3 and Figure 4 when being coexisted with the first sound absorption plate 12 closest to noise source
Wedge absorber 2 is clamped between two sound absorption plates 1.
As shown in figures 1 and 3, i.e., in first and third combination, wedge absorber 2 includes the second wedge absorber 22,
And the tip of the second wedge absorber 22 is connected with the tip of the first wedge absorber 21, i.e., second wedge absorber 22 can play just
Effect to the wedge absorber of mode, wherein the setting of the base portion of the first wedge absorber 21 close to noise source more convenient can be tieed up
Protect silencer, and the noise sound wave of different frequency by passing to the point of the second wedge absorber 22 after the first wedge absorber 21 first
Portion, from the tip of the second wedge absorber 22 to base portion, acoustic impedance is gradually to be transitioned into porous material from the characteristic impedance of air
Impedance, it is thus achieved that good impedance matching, so that incident sound be enable efficiently to be absorbed.In addition from the second sound absorption
The sound wave of the micro reflection of wedge 22 can be absorbed by the first wedge absorber 21, so that sound absorption effect is more preferable.
As shown in Figure 1, sound absorption plate 1 includes the first sound absorption plate 11 and second in the first combination of the invention
Absorb sound plate 12, and the first sound absorption plate 11 is connected to the base portion of the first wedge absorber 21, and the second sound absorption plate 12 is connected to the
The base portion of two wedge absorbers 22, i.e. first combination include above-mentioned various connection types.In this way, from anechoic room sounding body
Low-frequency noise is absorbed by the first sound absorption plate 11 first, and then noise sound wave successively passes through the first wedge absorber 21 and the second sound absorption
Wedge 22 makes the two further absorb the noise sound wave of different frequency, finally passes through second substantially all suction of sound absorption plate 12
The noise from anechoic room sounding body is received, and the first wedge absorber 21 can also be absorbed and be reflected from the second wedge absorber 22
Micro sound wave.Therefore, while can guarantee installation rigidity, make full use of the sound absorption of sound absorption plate 1 and wedge absorber 2 special
Point enables anechoic room to obtain excellent free found field characteristic, enhances sound absorption effect.
Further, silencer provided by the invention includes the peace for being installed to noise elimination main body on the inner wall of anechoic room
Loading board 3, and the exterior panel with the common cladding noise elimination main body of the mounting plate 3, that is, mounting plate 3 and exterior panel are around noise elimination main body
Outer wall forms a circle, wherein exterior panel is formed by entrant sound perforated plate, and entrant sound perforated plate is opened up in the front and back of density board
Have circular hole, there is good noise reduction sound absorbing performance, so as to further increase sound absorption effect, and in order to guarantee to install rigidity with
Intensity, mounting plate 3 can then use non-porous steel plate, the structural strength of Lai Zengqiang silencer entirety.
As shown in Figure 1, Figure 2 and Figure 4, the silencer includes sounding board, and sounding board is connected to noise elimination main body close to noise
The side in source.Wherein, sounding board can be to be coated on the exterior panel close to noise source part in above-mentioned exterior panel, the sounding board
Thickness can be for 1mm or so.It should be noted that the thickness close to the sounding board of noise source why is further limited,
It is and to be resonated using thin plate resonance sound-absorbing principle in order to which the sounding board is made into the lesser thin plate of thickness, is resonating in this way
In frequency, a large amount of absorption sound energy due to thin plate high vibration, and thin plate resonance has preferable sound absorbing performance in low frequency, from
And sound absorption effect can be enhanced.
In order to preferably realize the absorption of sound, the junction between sound absorption plate 1 and wedge absorber 2 is provided with connection
Plate, and connecting plate is formed by entrant sound perforated plate, can guarantee the installation rigidity of silencer while reaching and improving noise elimination effect.
In a preferred embodiment of the invention, the sound absorption plate 1 being connected with the base portion of wedge absorber 2 can be with the base portion
Shape and size it is identical, that is, sound absorption plate 1 is completely covered by the base portion of wedge absorber 2, in this way, either sound absorption plate 1 is also
It is that the base portion of wedge absorber 2 can play the effect for saving installation space close to the side of noise source, and be also convenient for safeguarding, together
When can guarantee install rigidity.The present invention also provides a kind of anechoic rooms, the inner wall in five faces in anechoic room in addition to ground
On sound absorption plate 1 and the silencer that is composed of wedge absorber 2 can be installed.
To sum up, silencer and anechoic room provided by the invention, silencer include putting down along the sound absorption that direction of sound propagation is connected
Plate 1 and wedge absorber 2, in this way, sound absorption plate 1 and wedge absorber that the sound for the different frequency that noise source issues can be connected
2 are absorbed, and the noise elimination effect after the two combines is significant.In addition, since sound absorption plate 1 is sharp compared to sound absorption under condition of equivalent thickness
It splits 2 more preferable for effect of low-frequency sound absorption, in the case where guaranteeing identical cutoff frequency, the thickness of noise elimination main body can be shortened, had
Help save the space of anechoic room.Therefore, compared to exclusive use sound absorption plate or wedge absorber, noise elimination provided by the invention
Device can significantly improve sound absorption effect, obtain excellent free found field, and convenient for safeguarding.Therefore, noise elimination provided by the invention
Device and the use of the anechoic room of the silencer is practicability with higher and promotional value.
It is described the prefered embodiments of the present invention in detail above in conjunction with attached drawing, still, the present invention is not limited to above-mentioned realities
The detail in mode is applied, within the scope of the technical concept of the present invention, a variety of letters can be carried out to technical solution of the present invention
Monotropic type, these simple variants all belong to the scope of protection of the present invention.
It is further to note that specific technical features described in the above specific embodiments, in not lance
In the case where shield, can be combined in any appropriate way, in order to avoid unnecessary repetition, the present invention to it is various can
No further explanation will be given for the combination of energy.
In addition, various embodiments of the present invention can be combined randomly, as long as it is without prejudice to originally
The thought of invention, it should also be regarded as the disclosure of the present invention.
Claims (7)
1. a kind of silencer, including noise elimination main body, which is characterized in that the noise elimination main body includes being connected along direction of sound propagation
Absorb sound plate (1) and wedge absorber (2)；
The wedge absorber (2) includes the first wedge absorber (21), and the base portion of first wedge absorber (21) is located at the noise elimination
Main body is closest to the side of noise source；
The wedge absorber (2) includes the second wedge absorber (22), and the tip of second wedge absorber (22) and described first inhale
The tip of sound wedge (21) is connected；
The sound absorption plate (1) includes the first sound absorption plate (11) and the second sound absorption plate (12), the first sound absorption plate
(11) it is connected to the base portion of first wedge absorber (21), second sound absorption plate (12) is connected to the second sound absorption point
Split the base portion of (22).
2. silencer according to claim 1, which is characterized in that the sound absorption plate (1) includes the first sound absorption plate
(11), which is located at the noise elimination main body closest to the side of noise source.
3. silencer according to claim 1 or 2, which is characterized in that the sound absorption plate (1) includes the second sound absorption plate
(12), which is located at the noise elimination main body closest to the side of the noise elimination chamber interior walls.
4. silencer according to claim 1, which is characterized in that the silencer includes for pacifying the noise elimination main body
The mounting plate (3) being attached on the inner wall of the anechoic room, and the outer of the noise elimination main body is coated jointly with the mounting plate (3)
Siding, the exterior panel are formed by entrant sound perforated plate, and the mounting plate (3) is formed by non-porous steel plate.
5. silencer according to claim 1 or 4, which is characterized in that the silencer includes sounding board, which connects
It connects in the noise elimination main body close to the side of noise source.
6. silencer according to claim 5, which is characterized in that the sound absorption plate (1) and the wedge absorber (2)
Between junction be provided with connecting plate, the connecting plate is formed by entrant sound perforated plate.
7. a kind of anechoic room, which is characterized in that the inner wall of the anechoic room is equipped with any one of -6 institute according to claim 1
The silencer stated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510958937.4A CN105575379B (en) | 2015-12-18 | 2015-12-18 | Anechoic room and silencer for it |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510958937.4A CN105575379B (en) | 2015-12-18 | 2015-12-18 | Anechoic room and silencer for it |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105575379A CN105575379A (en) | 2016-05-11 |
| CN105575379B true CN105575379B (en) | 2019-09-20 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510958937.4A Active CN105575379B (en) | 2015-12-18 | 2015-12-18 | Anechoic room and silencer for it |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105575379B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112779998A (en) * | 2020-12-31 | 2021-05-11 | 南京大学 | Full-band super-structure sound absorber |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107914440B (en) * | 2017-12-15 | 2019-12-13 | 芜湖尚唯汽车饰件有限公司 | Noise-reduction automobile interior trimming panel |
| CN118314861A (en) * | 2024-04-25 | 2024-07-09 | 苏州比翱科技集团有限公司 | Distributed sound absorption structure and application |
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| CN2064874U (en) * | 1990-05-31 | 1990-10-31 | 成都市噪声控制设备厂 | Ventilating air conditioner silencer |
| CN2405068Y (en) * | 2000-01-31 | 2000-11-08 | 王法源 | Comprehensive device for vibration damping and noise reducing in sound field |
| US6209680B1 (en) * | 2000-04-10 | 2001-04-03 | Jay Perdue | Acoustic diffuser panels and wall assembly comprised thereof |
| EP1901280A3 (en) * | 2001-09-27 | 2010-12-29 | Aloka Co., Ltd. | Ultrasonic probe |
| US8607925B2 (en) * | 2010-07-20 | 2013-12-17 | Hendrik David Gideonse | Wedge-shaped acoustic diffuser and method of installation |
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| JP3208046B2 (en) * | 1995-06-23 | 2001-09-10 | 株式会社ササクラ | Sound absorbing element and silencing elbow equipped with this |
| CN201369165Y (en) * | 2009-02-04 | 2009-12-23 | 纪洪鹏 | Combined sound insulation and absorption and noise reduction plate |
| CN202500097U (en) * | 2012-03-27 | 2012-10-24 | 江苏港峰亚太科技有限公司 | Combined sound barrier |
| CN202745228U (en) * | 2012-09-04 | 2013-02-20 | 北京科奥克声学技术有限公司 | Metal sound insulation low-frequency acoustic board |
| CN103452199A (en) * | 2013-09-13 | 2013-12-18 | 苏州岸肯电子科技有限公司 | Sound-absorbing wedge |
| CN203531166U (en) * | 2013-09-23 | 2014-04-09 | 华中科技大学 | Composite low-frequency sound barrier |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2064874U (en) * | 1990-05-31 | 1990-10-31 | 成都市噪声控制设备厂 | Ventilating air conditioner silencer |
| CN2405068Y (en) * | 2000-01-31 | 2000-11-08 | 王法源 | Comprehensive device for vibration damping and noise reducing in sound field |
| US6209680B1 (en) * | 2000-04-10 | 2001-04-03 | Jay Perdue | Acoustic diffuser panels and wall assembly comprised thereof |
| EP1901280A3 (en) * | 2001-09-27 | 2010-12-29 | Aloka Co., Ltd. | Ultrasonic probe |
| US8607925B2 (en) * | 2010-07-20 | 2013-12-17 | Hendrik David Gideonse | Wedge-shaped acoustic diffuser and method of installation |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112779998A (en) * | 2020-12-31 | 2021-05-11 | 南京大学 | Full-band super-structure sound absorber |
| CN112779998B (en) * | 2020-12-31 | 2022-04-22 | 南京大学 | Full-band super-structure sound absorber |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105575379A (en) | 2016-05-11 |
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Address after: 102206, Beijing, Shahe, Changping District Town, Sha Yang Road, Lao Wan Village North Applicant after: Beiqi Futian Automobile Co., Ltd. Address before: 102206 Changping District City, Shahe, Sha Yang Road, Beijing Applicant before: Beiqi Futian Automobile Co., Ltd. |
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