CN212478151U - Internal-inserting folding angle sound guide corridor type superstructure and low-frequency sound absorption device made of same - Google Patents
Internal-inserting folding angle sound guide corridor type superstructure and low-frequency sound absorption device made of same Download PDFInfo
- Publication number
- CN212478151U CN212478151U CN202020790250.0U CN202020790250U CN212478151U CN 212478151 U CN212478151 U CN 212478151U CN 202020790250 U CN202020790250 U CN 202020790250U CN 212478151 U CN212478151 U CN 212478151U
- Authority
- CN
- China
- Prior art keywords
- sound
- superstructure
- shell
- plate
- angle
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Devices Affording Protection Of Roads Or Walls For Sound Insulation (AREA)
- Building Environments (AREA)
Abstract
The utility model discloses an interpolation dog-ear leads sound vestibule formula superstructure and low frequency sound absorption device, superstructure includes shell and interpolation dog-ear board, and the shell is the cuboid form, and its cross-section perpendicular to length direction is the rectangle, and the rectangle forms the opening towards the long limit middle part of sound source one side, constitutes the sound transmission seam; the two inserted angle folding plates are respectively arranged at the left and the right in the rectangle, each inserted angle folding plate is of a thin plate structure formed by vertically bending at least once inwards, the starting ends of the two inserted angle folding plates are fixedly connected with one edge of the sound transmission seam in a sound-tight mode, and the other ends of the two inserted angle folding plates extend into the shell at one side of each inserted angle folding plate; the inner wall of each inserted angle plate and the inner wall of the shell form a cavity to form an air cavity; cavities are formed between the two inserted angle folding plates and between the outer wall of each inserted angle folding plate and the inner wall of the shell, and the cavities form a sound guide through outline and are used for guiding sound waves incident from the sound transmission seam to the air cavity. The low-frequency sound absorption device is good in noise reduction performance, small in thickness and capable of saving installation space.
Description
Technical Field
The utility model relates to a sound absorbing device field especially relates to an interpolation dog-ear leads sound vestibule formula superstructure and low frequency sound absorbing device who makes thereof.
Background
With the development of society, the requirements of people on the quality of indoor sound environments such as houses, office places, medical institutions and the like are gradually improved. The radiation noise of the indoor structure of the adjacent building caused by vibration of railways, subways or large mechanical equipment and the like is mainly low-frequency noise of 16-200 Hz, and has long propagation distance and strong penetrating power. Internal organs of a human body are sensitive to the low-frequency noise, and people easily feel uncomfortable after living in a low-frequency noise environment for a long time, so that normal work and life are affected, and therefore noise treatment is needed for indoor low-frequency secondary structure noise.
The traditional building indoor sound absorption material or sound absorption device is mainly designed for medium-high frequency noise transmitted by air, the sound absorption peak frequency is generally above 500Hz, and the noise reduction effect on low-frequency noise below 200Hz is poor. In order to achieve the low-frequency sound absorption effect, the sound absorption device usually needs to use a porous sound absorption material with large thickness, or a large-size cavity is reserved at the rear parts of the porous sound absorption material, a micro-perforated plate and the like to manufacture a space sound absorber, and the space sound absorber is difficult to implement in engineering due to the restriction of comprehensive factors such as space capacity, structural size, appearance artistry and the like.
SUMMERY OF THE UTILITY MODEL
One purpose of the utility model is to provide an interpolation dog-ear sound conduction corridor type superstructure which can carry out strong absorption and noise reduction on low-frequency noise, has smaller thickness and saves installation space;
another object of the utility model is to provide a low frequency sound absorbing device with above-mentioned interpolation dog-ear sound conduction vestibule formula superstructure.
Therefore, the technical scheme of the utility model is as follows:
an inserted folded angle sound guide corridor type superstructure comprises a shell and an inserted folded angle plate, wherein the shell is cuboid, the length of the shell is determined according to needs, the section of the shell, which is perpendicular to the length direction, is rectangular, and an opening is formed in the middle of the long edge of the rectangular side, which faces a sound source, so that a sound transmission seam is formed; the inner inserting angle folding plates are respectively arranged at the left and the right in the rectangle, each inner inserting angle folding plate is of a thin plate structure formed by vertically bending at least once towards the inner side, the starting ends of the two inner inserting angle folding plates are fixedly connected with one edge of the sound transmission seam in a sound-tight mode, and the other ends of the two inner inserting angle folding plates extend into the shell at one side of each inner inserting angle folding plate; the inner wall of each inserted angle plate and the inner wall of the shell form a cavity to form an air cavity; cavities are formed between the two inserted angle folding plates and between the outer wall of each inserted angle folding plate and the inner wall of the shell, and the cavities form a sound guide through outline and are used for guiding sound waves incident from the sound transmission seam to the air cavity.
Preferably, the two inserted gusset panels are symmetrically disposed within the housing.
Preferably, the width of the sound conduction channel between the two inserted folding plates is 2 mm-200 mm; the width of the sound conduction passing contour between the outer wall of each inserted angle plate and the inner wall of the shell is 2-200 mm; the internal length of the shell is 50 mm-5000 mm, and the internal width is 10 mm-1200 mm.
A low-frequency sound absorption device made of the above-mentioned interpolation angle sound conduction vestibule superstructure comprises two or more of the interpolation angle sound conduction vestibule superstructure and a sound absorption plate, wherein the two or more of the interpolation angle sound conduction vestibule superstructure are arranged side by side and the sound transmission seam faces to a sound source; the sound absorption plate is arranged on one side of the inner insertion folding angle sound guide corridor type superstructure with the sound transmission seam.
Preferably, the low-frequency sound absorption device further comprises a protection net, the protection net is made of hard metal or non-metal materials, the aperture ratio is greater than 80%, the thickness is smaller than 1mm, and the sound absorption plate is located between the inserted bevel angle sound guide corridor type superstructure and the protection net; the surfaces of the two or more interpolated dog-ear acoustic corridor superstructure adjacent to the acoustic panel form a plane.
Preferably, in the low frequency sound absorbing device, the total thickness of the internal folding angle sound guiding vestibule type superstructure is smaller than 1/15 of the corresponding wavelength of the acoustic resonance frequency.
The utility model discloses another kind is led the low frequency sound absorbing device that sound vestibule formula superstructure was made by above-mentioned interpolation dog-ear, lead sound vestibule formula superstructure composite unit and acoustic baffle including one or more interpolation dog-ear, interpolation dog-ear leads sound vestibule formula superstructure composite unit and comprises three interpolation dog-ear formula superstructure, and wherein first and second superstructure interval sets up side by side, and the third superstructure is located first and second superstructure below; the gap between the first superstructure and the second superstructure is the same as and is communicated with the sound transmission gap width of the third superstructure; the overall shape width of the first and second superstructures is the same as the width of the third superstructures; the sound absorption plate is arranged on one side of the inner insertion folding angle sound guide corridor type superstructure combined unit with the sound transmission seam.
Preferably, the low-frequency sound absorption device further comprises a protection net, the protection net is made of hard metal or non-metal materials, the aperture ratio is greater than 80%, the thickness is smaller than 1mm, and the sound absorption plate is located between the internal insertion folding angle sound guide corridor type superstructure combination unit and the protection net. The integral thickness of the interpolation bevel sound guide vestibule type superstructure combination unit is less than 1/15 of the wavelength corresponding to the acoustic resonance frequency.
The utility model discloses in, the sound conduction sectional area that the sound conduction leads to the outline is less, the sound conduction distance is longer, the sound resonance frequency that interpolation dog-ear leads sound vestibule formula superstructure is lower. The interpolated folding angle sound guide vestibule type superstructure is coupled with the sound absorption plate to generate a low-frequency strong sound absorption effect below 200Hz, and the result of the coupling action determines the sound absorption coefficient of the low-frequency sound absorption device at each frequency.
The utility model has the advantages of it is following and positive effect:
1. the utility model discloses utilize acoustics superstructure to make low frequency sound absorbing device, under the relatively less prerequisite of overall dimension, utilize inside artifical structure, reduce sound absorption peak value place frequency, possess the strong absorption noise reduction performance to low-frequency noise below 200 Hz.
2. The utility model provides an interpolation dog-ear leads sound vestibule and has overcome the dependence of low frequency sound absorbing device to the jumbo size cavity, has greatly practiced thrift installation space.
3. Compared with the existing sound absorption material or sound absorption device, the device has smaller overall thickness and better low-frequency sound absorption coefficient, the average sound absorption coefficient of 50-200 Hz is more than 0.4, the sound absorption peak value is more than 0.8, the frequency of the sound absorption peak value is controllable, and an efficient solution is provided for controlling the radiation noise of the indoor structure of the building.
Drawings
Fig. 1 and 2 are schematic cross-sectional views of an internal-insertion bevel sound-guide vestibule superstructure according to two embodiments of the present invention, wherein a dotted line represents a boundary line between a sound-guide vestibule and an air cavity;
FIG. 3 is a schematic cross-sectional view of the housing;
fig. 4 is a schematic cross-sectional view of an embodiment of the low frequency sound absorption device of the present invention;
FIG. 5 is a plot of the measured sound absorption performance of the low frequency sound absorption apparatus of FIG. 4;
fig. 6 and 7 are schematic cross-sectional views of another embodiment of the low frequency sound absorber of the present invention;
fig. 8 is a simulated predicted sound absorption performance curve of the low frequency sound absorption device of example 2.
In the figure:
1. interpolation dog-ear leads sound vestibule formula superstructure 2, shell 3, interpolation dog-ear board
4. Sound conducting corridor 5, air cavity 6, sound transmission seam 7 and sound absorption plate
8. Protective net
Detailed Description
The structure of the internal insertion bevel sound guiding vestibule superstructure and the low frequency sound absorption device made by the same of the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.
Example 1
As shown in fig. 1 and 3, an inserted bevel sound leading vestibule type superstructure comprises a housing 2 and an inserted bevel plate 3, wherein the housing 2 is cuboid, the length of the housing is determined according to needs, the section of the housing perpendicular to the length direction is rectangular, and an opening is formed in the middle of the long side of the rectangular side facing a sound source to form a sound transmission seam 6.
The two inserted angle folding plates 3 are symmetrically arranged in the rectangle in the left and right directions, each inserted angle folding plate 3 is of a thin plate structure formed by vertically bending the two inserted angle folding plates 3 towards the inner side twice, the starting ends of the two inserted angle folding plates 3 are fixedly connected with one edge of the sound transmission seam 6 in a sound leakage-proof mode, and the other ends of the two inserted angle folding plates 3 extend into the shell 2 on one side of each inserted angle folding plate; the cavity enclosed by the inner wall of each block of the inserted angle folding plate 3 and the inner wall of the shell 2 forms an air cavity 5; cavities are formed between the two inserted angle folding plates 3 and between the outer wall of each inserted angle folding plate and the inner wall of the shell 2, and the cavities form a sound guide through outline 4 for guiding sound waves incident from the sound transmission seam 6 to the air cavity 5.
Example 2
As shown in fig. 2 and 3, an inserted bevel sound leading vestibule type superstructure comprises a housing 2 and an inserted bevel plate 3, wherein the housing 2 is cuboid, the length of the housing is determined according to needs, the section of the housing perpendicular to the length direction is rectangular, and an opening is formed in the middle of the long side of the rectangular side facing a sound source to form a sound transmission gap 6.
The two inserted angle folding plates 3 are symmetrically arranged in the rectangle left and right, each inserted angle folding plate 3 is of a thin plate structure formed by vertically bending three times towards the inner side, the starting ends of the two inserted angle folding plates 3 are fixedly connected with one edge of the sound transmission seam 6 in a sound leakage-proof mode, and the other ends of the two inserted angle folding plates 3 extend into the shell 2 on one side of each inserted angle folding plate; the cavity enclosed by the inner wall of each block of the inserted angle folding plate 3 and the inner wall of the shell 2 forms an air cavity 5; cavities are formed between the two inserted angle folding plates 3 and between the outer wall of each inserted angle folding plate and the inner wall of the shell 2, and the cavities form a sound guide through outline 4 for guiding sound waves incident from the sound transmission seam 6 to the air cavity 5.
Example 3
Fig. 4 shows that the utility model discloses a low frequency sound absorption device is made by above-mentioned interpolation dog-ear sound conduction vestibule formula superstructure. As shown in the figure, the low frequency sound absorption device comprises two internal inserted folding angle sound guide vestibule type superstructure 1, a sound absorption plate 7 and a protection net 8. The overall thickness of the interpolated dog-ear acoustic corridor superstructure is less than 1/15 for the wavelength corresponding to the acoustic resonance frequency.
Two interpolation dog-ear lead sound vestibule formula superstructure 1 place side by side and pass through sound seam 6 and all face the sound source. In this embodiment, the outer shell of the superstructure 1 and the inserted angle folding plate 3 are both made of aluminum alloy plates with a thickness of 3 mm. The internal horizontal dimension L1 of the first superstructure is 394mm, the internal height H1 is 124mm, the sound guide corridor section width a1 is 25mm, the b1 is c1 is 19mm, and the length of the 2-piece inserted folding angle plate is 352 mm. The second superstructure has an internal horizontal dimension L2-394 mm, an internal height H2-124 mm, a sound guidance corridor cross-sectional width a 2-25 mm, and a b 2-c 2-19 mm. The lengths of the 2-piece internal insertion folding plates (the cross-sectional lengths of the internal insertion folding plates in the figure) are all 402 mm.
The sound absorption plate is installed at one side of the inserted bevel angle sound conduction corridor type superstructure 1 with the sound transmission seam 6, is located between the inserted bevel angle sound conduction corridor type superstructure 1 and the protection net 8, and the surfaces of two or more inserted bevel angle sound conduction corridor type superstructure 1 adjacent to the sound absorption plate 7 form a plane. The sound absorption plate is made of light porous material, can be made of one material, and can also be formed by laminating and splicing multiple materials. The thickness of the sound absorption plate 7 is smaller than 1/5 of the thickness of the inner inserting folding angle sound guide vestibule type superstructure 1, so that the whole installation space of the sound absorption device is saved. In this embodiment, the sound absorbing panel is a mineral wool panel with a thickness of 16 mm.
The protective net 8 is a selectively installed protective device and does not affect the acoustic performance, the protective net 8 is made of hard metal or nonmetal materials, the aperture ratio is greater than 80%, and the thickness is smaller than 1 mm. In this example, the protective mesh was 0.5mm thick, made of aluminum alloy, and had an aperture ratio of 95%.
The overall thickness of the low frequency sound absorption device is 146.5 mm.
The sound absorption plate 7 is positioned between the internal inserting folding angle sound guide corridor type superstructure 1 and the protection net 8; the protection net 8 is fixedly connected with the edge of the inserted bevel sound guide vestibule type superstructure 1; the surface of the superstructure 1 adjacent to the sound absorption panel 7 is planar.
The actual measurement result of the sound absorption coefficient frequency spectrum of the low-frequency sound absorption device is shown in fig. 5, the average sound absorption coefficient is 0.44 within the range of 50-200 Hz, and the sound absorption coefficient is 0.81 at 100 Hz. Due to the combined action of the superstructure and the porous material, the low-frequency sound absorption device has a high sound absorption coefficient at the central resonance frequency of 100Hz, and simultaneously keeps a high sound absorption coefficient at the central frequencies of 80Hz and 125Hz of two adjacent 1/3 octaves, so that the effective sound absorption frequency range is wide.
Example 4
Fig. 6 and 7 show another embodiment of the low frequency sound absorber of the present invention. As shown, the low frequency sound absorbing device includes at least one internal folding angle sound guiding vestibule type superstructure combining unit and a sound absorbing plate 7.
The interpolation bevel sound guide corridor type superstructure combination unit consists of three interpolation bevel sound guide corridor type superstructures, wherein a first superstructure and a second superstructure are arranged side by side at intervals, and a third superstructure is positioned below the first superstructure and the second superstructure; the gap between the first superstructure and the second superstructure is the same as and is through the width of the sound-transmitting seam 6 of the third superstructure; the overall profile width of the first and second superstructure is the same as the width of the third superstructure. The sound absorption plate is arranged on one side of the inner insertion folding angle sound guide corridor type superstructure combined unit, which is provided with the sound transmission seam 6. The sound absorption plate 7 is arranged at one side of the inner inserted folding angle sound guide corridor type superstructure combined unit, which is provided with the sound transmission seam 6.
In the sound absorption device, the whole thickness of the internal-inserted bevel sound guide vestibule type superstructure combination unit is smaller than 1/15 of the wavelength corresponding to the sound resonance frequency.
In the embodiment, the shell and the inserted angle folding plate of each superstructure are made of aluminum alloy plates with the thickness of 3 mm. Wherein the first and second superstructures are spaced 30mm apart. The internal structure of the first superstructure and the second superstructure is the same, the internal horizontal dimension L1-L2-377 mm, the internal height H1-H2-60 mm, the sound guide corridor cross-section width a 1-b 1-c 1-a 2-b 2-c 2-20 mm, and the lengths of the inserted folding angle plates (the cross-section lengths of the inserted folding angle plates in the figure) are both 80 mm. The third superstructure has an internal horizontal dimension L3-790 mm, an internal height H3-61 mm, a sound guide corridor cross-section width a 3-30 mm, a b 3-c 3-25 mm, and 2 sheet internal folding angle plates (the cross-section lengths of the internal folding angle plates in the figure) are all 170 mm.
The sound absorption device also comprises a protection net 8, wherein the protection net 8 is made of hard metal or nonmetal materials, the aperture ratio is greater than 80%, and the thickness is smaller than 1 mm. And the sound absorption plate 7 is positioned between the internal insertion folding angle sound guide corridor type superstructure combined unit and the protection net 8. In the embodiment, the thickness of the protective net 8 is 0.5mm, the protective net is made of aluminum alloy, and the aperture ratio is 95%; the sound absorption plate 7 is a glass wool plate with the thickness of 16 mm.
The overall thickness of the low frequency sound absorption device is 146.5 mm.
The sound absorption coefficient frequency spectrum prediction result of the low-frequency sound absorption device is shown in fig. 8, the average sound absorption coefficient is 0.54 within the range of 50-200 Hz, and the sound absorption coefficients of 100Hz and 200Hz reach 0.92 and 0.95. The low-frequency sound absorption device has extremely high sound absorption coefficient peak under the combined action of the three superstructures and the porous sound absorption material.
The above description is only exemplary of the present invention and should not be construed as limiting the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The utility model provides an interpolation dog-ear leads sound vestibule formula superstructure which characterized in that: comprises a shell (2) and an inserted angle folding plate (3),
the shell (2) is cuboid, the length of the shell is determined according to requirements, the section of the shell perpendicular to the length direction is rectangular, and an opening is formed in the middle of the long side of the rectangular side facing the sound source to form a sound transmission seam (6);
the inserted angle folding plates (3) are respectively arranged on the left and right sides in the rectangle, each inserted angle folding plate (3) is of a thin plate structure formed by vertically bending at least once towards the inner side, the starting ends of the two inserted angle folding plates (3) are fixedly connected with one edge of the sound transmission seam (6) in a sound leakage-proof mode, and the other ends of the two inserted angle folding plates (3) respectively extend into the shells (2) on one side of each inserted angle folding plate;
a cavity enclosed by the inner wall of each inserted angle plate (3) and the inner wall of the shell (2) forms an air cavity (5);
cavities are formed between the two inserted angle folding plates (3) and between the outer wall of each inserted angle folding plate and the inner wall of the shell (2), and the cavities form a sound guide through contour (4) for guiding sound waves incident from the sound transmission seam (6) to the air cavity (5).
2. The interpolated dog-ear vestibular superstructure according to claim 1, characterized in that: the two inserted angle folding plates (3) are symmetrically arranged in the shell (2).
3. The interpolated dog-ear vestibular superstructure according to claim 1, characterized in that: the width of the sound conduction channel (4) between the two inserted angle folding plates (3) is 2-200 mm; the width of the sound conduction channel (4) between the outer wall of each inserted angle plate and the inner wall of the shell (2) is 2-200 mm; the inner length of the shell (2) is 50 mm-5000 mm, and the inner width is 10 mm-1200 mm.
4. The interpolated dog-ear vestibular superstructure according to claim 1, characterized in that: the outer shell (2) and the inserted angle folding plates (3) are made of hard metal or non-metal materials.
5. A low frequency sound absorbing device made of the interpolating dog-ear acoustic corridor superjunction structure of any of claims 1-4, wherein: comprises two or more than two internal inserting folding angle sound guide vestibule type superstructure (1) and a sound absorption plate (7),
two or more interpolation angle sound conduction vestibule type superstructures (1) are placed side by side, and sound transmission seams (6) face to a sound source;
the sound absorption plate is arranged on one side of the inner inserting folding angle sound guide corridor type superstructure (1) provided with the sound transmission seam (6).
6. The low frequency sound absorbing device of claim 5, wherein: the sound absorption structure is characterized by further comprising a protection net (8), wherein the protection net (8) is made of hard metal or non-metal materials, the aperture ratio is larger than 80%, the thickness is smaller than 1mm, and the sound absorption plate (7) is located between the inner insertion folding angle sound guide corridor type superstructure (1) and the protection net (8); the surfaces of the two or more internal folding angle sound conduction gallery type superstructures (1) adjacent to the sound absorption plate (7) form a plane.
7. The low frequency sound absorbing device of claim 5, wherein: the integral thickness of the interpolation bevel sound conduction vestibule type superstructure is less than 1/15 of the wavelength corresponding to the sound resonance frequency.
8. A low frequency sound absorbing device made of the interpolating dog-ear acoustic corridor superjunction structure of any of claims 1-4, wherein: comprises at least one internal inserted folding angle sound guide corridor type superstructure combined unit and a sound absorption plate (7),
the interpolation bevel sound guide corridor type superstructure combination unit consists of three interpolation bevel sound guide corridor type superstructures, wherein a first superstructure and a second superstructure are arranged side by side at intervals, and a third superstructure is positioned below the first superstructure and the second superstructure; the gap between the first superstructure and the second superstructure is the same as and is communicated with the sound transmission gap (6) of the third superstructure; the overall shape width of the first and second superstructures is the same as the width of the third superstructures;
the sound absorption plate is arranged on one side of the inner insertion folding angle sound guide corridor type superstructure combined unit with the sound transmission seam (6).
9. The low frequency sound absorbing device of claim 8, wherein: still include protection network (8), protection network (8) are made by hard metal or non-metal material, and the percent opening is greater than 80%, and thickness is less than 1mm, sound-absorbing board (7) are located between interpolation dog-ear leading sound vestibule formula superstructure composite unit and protection network (8).
10. The low frequency sound absorbing device of claim 8, wherein: the integral thickness of the interpolation bevel sound guide vestibule type superstructure combination unit is less than 1/15 of the wavelength corresponding to the acoustic resonance frequency.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020790250.0U CN212478151U (en) | 2020-05-13 | 2020-05-13 | Internal-inserting folding angle sound guide corridor type superstructure and low-frequency sound absorption device made of same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020790250.0U CN212478151U (en) | 2020-05-13 | 2020-05-13 | Internal-inserting folding angle sound guide corridor type superstructure and low-frequency sound absorption device made of same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212478151U true CN212478151U (en) | 2021-02-05 |
Family
ID=74460561
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020790250.0U Active CN212478151U (en) | 2020-05-13 | 2020-05-13 | Internal-inserting folding angle sound guide corridor type superstructure and low-frequency sound absorption device made of same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212478151U (en) |
-
2020
- 2020-05-13 CN CN202020790250.0U patent/CN212478151U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105803965A (en) | Wideband sound absorption unit plate | |
| CN210639980U (en) | Inhale sound insulation composite member and transformer | |
| CN211597189U (en) | Wall structure capable of effectively reducing noise | |
| CN204356925U (en) | A kind of indoor substation low frequency absorption denoising device | |
| JP2018053708A (en) | Sound insulation louver | |
| CN205529956U (en) | Broadband sound absorption cell board | |
| CN111549922A (en) | Internally-inserted folded angle sound guide corridor type superstructure and low-frequency sound absorption device manufactured by same | |
| CN210639979U (en) | Inhale sound insulation composite member and transformer | |
| CN212478151U (en) | Internal-inserting folding angle sound guide corridor type superstructure and low-frequency sound absorption device made of same | |
| EP1633939B1 (en) | Flexible covering system and corresponding modules for walls, ceilings and other boundaries | |
| CN207512950U (en) | Three-dimensional alliteration impedance micropunch period ultrabroad band flush sound absorption structure | |
| CN215518460U (en) | Structure with noise reduction and sound insulation functions | |
| JP2020166122A (en) | Noise reduction structure | |
| CN210317081U (en) | Stainless steel soundproof door | |
| CN213038228U (en) | Sound absorbing element barrier for wide-tone noise | |
| CN210896602U (en) | Cavity sound absorption structure of sound absorption protective surface of double-sided metal perforated plate in acoustic laboratory | |
| CN215926356U (en) | Double-acoustic-channel superstructure and wide-frequency-domain noise reduction device manufactured by same | |
| CN210805210U (en) | Porous sound absorption plate and sound absorption device | |
| CN206110345U (en) | Heat and sound isolation prefabricated house | |
| CN111332413A (en) | Fireproof return air silencer for ship cabin | |
| CN213979280U (en) | Sound insulation structure of light house | |
| CN214117941U (en) | Sound-proof glass for external window | |
| CN213390941U (en) | Assembled antibacterial ultramicropore metal composite sound absorption wallboard | |
| JP2020165200A (en) | Opening structure for ventilation | |
| CN220065172U (en) | Low-frequency adjustable noise absorption device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |