CN112750415B - Composite broadband sound absorption structure - Google Patents
Composite broadband sound absorption structure Download PDFInfo
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- CN112750415B CN112750415B CN202110115532.XA CN202110115532A CN112750415B CN 112750415 B CN112750415 B CN 112750415B CN 202110115532 A CN202110115532 A CN 202110115532A CN 112750415 B CN112750415 B CN 112750415B
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- perforated plate
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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
- G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects
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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
- G10K11/162—Selection of materials
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
- Building Environments (AREA)
Abstract
The composite broadband sound absorption structure comprises a support frame, a multilayer sound absorption assembly and a fixing assembly, wherein the multilayer sound absorption assembly comprises an elastic film layer, a perforated plate layer I and a perforated plate layer II which are sequentially arranged from top to bottom and are horizontally arranged, and the support frame is arranged on the outer side of the multilayer sound absorption assembly in a surrounding manner and is used for clamping and accommodating the flexible multilayer sound absorption assembly; the fixing assembly comprises a pressure plate and fastening screws and is used for fixing the multi-layer sound absorption assembly on the inner wall surface of the supporting frame. The sound absorption structure is simple in structure, convenient to install, light in weight, wide in sound absorption frequency band, good in effect and wide in application range, and has the capability of being widely applicable to noise reduction and sound absorption in various fields.
Description
Technical Field
The invention relates to the technical field of sound absorption and noise reduction equipment, in particular to a novel composite broadband sound absorption structure which comprehensively applies a multilayer sound absorption principle and can be applied to various occasions.
Technical Field
At present, with the development of the age, the living standard of people is continuously improved, the technology level is increasingly refined, and the requirements on noise reduction are higher and higher for civil and military devices. However, in the noise reduction process, the technology and cost for controlling noise from the source are sometimes high, and the predetermined noise reduction target is not easy to achieve. Thus, there is a need to achieve noise reduction by adding sound absorbing devices in the propagation path and before the final recipient. The sound absorption structure in the prior art is multifunctional, single in structure, less in sound absorption frequency band and heavy in weight, so that the sound absorption effect is very limited.
Disclosure of Invention
The technical purpose of the invention is as follows: the composite wideband sound absorption structure has the advantages of simple structure, light weight, wide sound absorption frequency range and good effect, and can utilize the microperforation technology to couple the Helmholtz resonant cavity and the film resonance technology to quickly and effectively absorb noise in different frequency ranges in the surrounding environment so as to realize the wideband noise reduction effect.
In order to achieve the technical purpose, the invention adopts the following technical scheme: the composite broadband sound absorption structure comprises a supporting frame, a multilayer sound absorption assembly and a fixing assembly, wherein the multilayer sound absorption assembly comprises an elastic film layer, a perforated plate layer I and a perforated plate layer II which are sequentially arranged from top to bottom and are horizontally arranged, the perforated plate layer II is of a flat plate structure and is arranged at the bottom of the supporting frame, a central through hole II communicated with the outside is formed in the center of the perforated plate layer II, a plurality of sound absorption holes II which are vertically arranged and communicated with the outside are also formed in the lower end face of the perforated plate layer II, and the sound absorption holes II have different depths and are smaller than the thickness of the perforated plate layer II; the perforated plate layer I is also of a flat plate structure, the perforated plate layer I is arranged above the perforated plate layer II, a central through hole I is formed in the center of the perforated plate layer I, the central through hole I and the central through hole II are communicated with each other, the diameter of the central through hole I is larger than that of the central through hole II, a circle of annular partition plate is also enclosed on the outer circumference of the central through hole I, the height of the annular partition plate is consistent with the thickness of the perforated plate layer I, a plurality of sound transmission holes are also horizontally formed in the annular partition plate, the perforated plate layer I comprises a plurality of layers of perforated plates which are arranged at intervals up and down, one end of each layer of perforated plate close to the central through hole I is vertically fixed on the annular partition plate, a supporting piece for supporting the upper layer of perforated plate is also arranged between every two adjacent layers of perforated plates, the supporting pieces are of different in height, each two adjacent layers of perforated plates, the supporting piece and the partition plate together form a sound absorption cavity for absorbing noise, each sound absorption cavity is communicated with the central through the sound transmission holes I on the annular partition plate, and each layer of perforated plate is vertically arranged on each layer of perforated plate and is vertically communicated with the sound absorption cavities I; the elastic film layer covers the perforated plate layer I in the positive direction, so that the whole multi-layer sound absorption assembly forms a sealing structure at the top end;
the supporting frame is arranged on the outer side of the multilayer sound absorption assembly in a surrounding mode and is used for clamping and accommodating the flexible multilayer sound absorption assembly;
the fixing assembly comprises a pressing plate and fastening screws, wherein the pressing plate comprises a vertical coaming and a horizontal annular pressing ring, the coaming is attached to the inner wall surface of the supporting frame, the annular pressing ring is pressed on the upper surface of the elastic film layer, which is far away from the center end, the pressing plate is fixed on the supporting frame 1 through preset threaded holes on the coaming, and the pressing plate is rigidly connected with the elastic film layer and the supporting frame.
Preferably, the supporting frame is in a cylindrical structure with openings at the upper end and the lower end.
Preferably, the plurality of sound absorbing holes II are uniformly formed in the lower end face of the perforated plate layer II, and the hole depths of the plurality of sound absorbing holes II are continuously increased from the end far away from the axis line to the end close to the axis line in the radial direction along the perforated plate layer II.
Preferably, the perforated plate layer I and the perforated plate layer II are flexibly connected.
Preferably, the support frame is made of a hard material.
Preferably, the height of the support member increases from top to bottom in the thickness direction of the perforated plate layer i.
Preferably, the support member is supported below the end of the perforated plate facing away from the central through hole I.
Preferably, the sound absorbing holes I on each layer of perforated plate are uniformly arranged.
Preferably, the elastic film layer is glued to the upper surface of perforated plate layer i.
Preferably, the coaming and the annular pressing ring are of an integrated structure.
The beneficial effects are that:
the composite broadband sound absorption structure is simple in structure and convenient to install. The sound absorption structure is integrally formed by adopting a micro-perforation technology, a Helmholtz resonant cavity technology and a film resonance technology in a coupling mode, and through the design of micro-perforation apertures, intervals and depths with different diameters on a perforation plate layer I, a perforation plate layer II and a circular baffle plate; the Helmholtz resonant cavity is formed in the sound absorption structure by combining the central through hole I and the central through hole II; and cover in perforation lamina I and perforation lamina II top, self have elastic membrane effect of elastic membrane layer, realized high, well, low multiple frequency band broadband sound absorption, noise reduction effect to effectively promoted the sound absorption ability of low frequency noise. The structure has the characteristics of light weight, wide sound absorption frequency band, good sound absorption effect and wide application range, can quickly and effectively solve the noise absorption problem of different environments, is widely applicable to noise reduction and sound absorption in various fields, and has good practical effect.
Drawings
FIG. 1 is a schematic cross-sectional view of the structure of the present invention;
the marks in the figure: 1. the support frame, 2, elastic film layer, 3, perforation lamina (I), 4, perforation lamina (II), 5, central through hole (II), 6, sound absorption hole (II), 7, central through hole (I), 8, annular baffle, 9, sound transmission hole, 10, support piece, 11, sound absorption chamber, 12, sound absorption hole (I), 13, pressure disk, 14, fastening screw.
Detailed Description
In order to make the technical problems, technical schemes and effects to be solved more clear, the invention is further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
As shown in fig. 1, a composite wideband sound absorption structure is composed of a supporting frame 1, a multi-layer sound absorption assembly and a fixing assembly, wherein the supporting frame is arranged at the outer end, and an elastic film layer 2, a perforated plate layer i 3 and a perforated plate layer ii 4 are sequentially arranged inside the supporting frame from top to bottom. The multilayer sound absorption assembly comprises an elastic film layer 2, a perforated plate layer I3 and a perforated plate layer II 4 which are sequentially arranged from top to bottom and are horizontally arranged, wherein the perforated plate layer II 4 is of a flat plate structure and is directly arranged on the inner bottom surface of a supporting frame 1, a central through hole II 5 communicated with the outside is formed in the center of the perforated plate layer II 4, a plurality of sound absorption holes II 6 which are vertically arranged and communicated with the outside are formed in the lower end surface of the perforated plate layer II 4, and the sound absorption holes II 6 have different depths and are smaller than the thickness of the perforated plate layer II 4; the sound absorption holes II 6 are uniformly formed in the lower end face of the perforated plate layer II 4, and the hole depth of the sound absorption holes II 6 is continuously increased from the end far away from the axis line to the end close to the axis line in the radial direction of the perforated plate layer II 4.
Perforation sheet layer I3 also be dull and stereotyped form structure, and perforation sheet layer I3 lay in the top of perforation sheet layer II 4 to with flexible coupling between perforation sheet layer II 4, set up a central through-hole I7 in the center department of perforation sheet layer I3, this central through-hole I7 link up each other with central through-hole II 5, and the diameter of central through-hole I7 is greater than the diameter of central through-hole II 5, still enclose on the outer circumference of central through-hole I7 and be equipped with round annular baffle 8, the high of this round annular baffle 8 is unanimous with the thickness of perforation sheet layer I3, and round annular baffle 8 is last still the level to be provided with a plurality of sound-absorbing holes 9, perforation sheet layer I3 include the multilayer perforated plate that upper and lower interval set up, the one end that every layer perforated plate is close to central through-hole I7 is all fixed perpendicularly on round annular baffle 8, still be provided with a support 10 that is used for supporting upper layer perforated plate I7 between every adjacent two layers, support 10 support in the below that deviates from central through-hole I7 one end, a plurality of support 10 have different heights, along the thickness of perforated plate I3, the sound-absorbing layer I is high and the sound-absorbing layer I is set up with the sound-absorbing layer I is perpendicular to the sound-absorbing layer 11 that is perpendicular to the top-absorbing layer I3, the sound-absorbing layer is connected to the sound-absorbing layer I is perpendicular to the top-absorbing layer I is set up to the sound-absorbing layer I3.
The elastic film layer 2 is glued and covered on the positive direction of the perforated plate layer I3, so that the whole multi-layer sound absorption assembly forms a sealing structure at the top end.
The supporting frame 1 is arranged on the outer side of the multilayer sound absorption assembly in a surrounding mode, is in a cylindrical structure with openings at the upper end and the lower end, and is made of a hardness material and used for clamping and accommodating the flexible multilayer sound absorption assembly.
The fixing assembly comprises a pressing plate 13 and fastening screws 14, wherein the pressing plate 13 comprises a vertical coaming and a horizontal annular pressing ring, the coaming and the annular pressing ring are of an integrated structure, the coaming is attached to the inner wall surface of the supporting frame 1, the annular pressing ring is pressed on the upper surface of the elastic film layer 2, which is far away from the center end, the fastening screws 14 fix the pressing plate 13 on the supporting frame 1 through preset threaded holes on the coaming, and the pressing plate 13 is rigidly connected with the elastic film layer 2 and the supporting frame.
Preferably, the perforated plate layer i 3 is formed by four perforated plates, and the heights of the sound absorption cavities 11 between every two perforated plates are different.
The sound absorption holes I12, the sound absorption holes II 6 and the sound transmission holes on the perforated plate layer I3, the perforated plate layer II 4 and the annular partition plate 8 are of microporous structures, and the diameters of the sound absorption holes I12, the sound absorption holes II 6 and the sound transmission holes can be adjusted according to actual needs so as to achieve the purpose of absorbing noise in a specific frequency range in the auditory range of human ears; the elastic film layer 2 is a nonmetallic elastic film.
The multilayer sound absorption component in the sound absorption structure is fixed on the supporting frame 1 through the pressure plate 13 and the fastening screw 14, and sealant can be smeared between the contact surface of the pressure plate 13 and the fixed elastic film layer 2 when necessary. The invention has the characteristics of simple structure, convenient installation, light weight, wide sound absorption frequency range, good effect and wide application range. Is a novel composite sound absorption structure with simple structure, low cost and good practical effect.
When the composite broadband sound absorption structure is specifically installed and used, the supporting frame 1 is an external supporting component which is prepared in advance, after the supporting frame is prepared, a central through hole II 5 is formed in the center of the perforated plate layer II 4, a plurality of sound absorption holes II with equal apertures but unequal depths are punched in the lower end face of the perforated plate layer II 4 according to the sound absorption design requirement, the maximum depth of the sound absorption holes II does not exceed the thickness of the perforated plate layer II 4, and the perforated plate layer II 4 is installed at the inner bottom of the cylindrical supporting frame 1. Then, a plurality of sound absorption holes I12 with equal aperture are uniformly drilled on each layer of perforated plate in the perforated plate layer I3 according to the sound absorption design requirement, then a central through hole I7 is formed in the center of the perforated plate layer I3, a circular annular partition plate 8 is arranged on the outer circumference of the central through hole I7, a plurality of sound transmission holes 9 are horizontally formed in the circular annular partition plate 8, the finished perforated plate layer I3 and the circular annular partition plate 8 are placed in the supporting frame 1, and the upper part of the perforated plate layer II 4 is provided. Then, the elastic film layer 2 is adhered to the upper portion of the perforated plate layer I3 by means of adhesion so as to cover the whole perforated plate layer I3 and the whole perforated plate layer II 4, and the top-sealed multilayer sound absorption assembly is formed. Finally, a pressing plate 13 is arranged above the elastic film layer 2, and the pressing plate 13 is fixed at the edge position inside the supporting frame 1 by fastening screws 14, so that a complete sound absorption structure whole is formed, and as shown in fig. 1, sound absorption can be performed.
Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but although the present invention has been described in detail with reference to the foregoing embodiment, it will be apparent to those skilled in the art that modifications may be made to the technical solution described in the foregoing embodiment, or equivalents may be substituted for some of the technical features thereof. Any modification, equivalent replacement, improvement, etc. made within the idea of the present invention should be included in the scope of the present invention.
Claims (10)
1. The utility model provides a compound broadband sound absorbing structure, this sound absorbing structure comprises braced frame (1), multilayer sound absorbing component and fixed subassembly, its characterized in that: the multilayer sound absorption assembly comprises an elastic film layer (2), a perforated plate layer I (3) and a perforated plate layer II (4) which are sequentially arranged from top to bottom and are horizontally arranged, wherein the perforated plate layer II (4) is of a flat plate structure and is arranged at the bottom of a supporting frame (1), a central through hole II (5) communicated with the outside is formed in the center of the perforated plate layer II (4), a plurality of sound absorption holes II (6) which are vertically arranged and are communicated with the outside are formed in the lower end face of the perforated plate layer II (4), and the sound absorption holes II (6) have different depths and are smaller than the thickness of the perforated plate layer II (4); the perforated plate layer I (3) is also of a flat plate structure, the perforated plate layer I (3) is arranged above the perforated plate layer II (4), a central through hole I (7) is formed in the center of the perforated plate layer I (3), the central through hole I (7) and the central through hole II (5) are mutually communicated, the diameter of the central through hole I (7) is larger than that of the central through hole II (5), a circle of annular partition plate (8) is further arranged on the outer circumference of the central through hole I (7) in a surrounding mode, the height of the annular partition plate (8) is consistent with the thickness of the perforated plate layer I (3), a plurality of sound transmission holes (9) are further horizontally arranged on the annular partition plate (8), the perforated plate layer I (3) comprises a plurality of layers of perforated plates which are arranged at intervals up and down, one end of each layer of perforated plate close to the central through hole I (7) is vertically fixed on the annular partition plate (8), a supporting piece (10) for supporting the perforated plate of the upper layer is also arranged between every two adjacent layers of perforated plates, and the supporting pieces (10) are provided with different heights, so that each two adjacent layers of perforated plates, the supporting piece (10) and the partition plate enclose an acoustic absorption cavity (11) for absorbing noise together, each acoustic absorption cavity (11) is communicated with the central through hole I (7) through an acoustic transmission hole (9) on the annular partition plate (8), and a plurality of vertical settings are respectively arranged on each layer of perforated plates in a vertical mode and are perpendicular to the plate surface, and the sound absorption holes I (12) are communicated with the adjacent sound absorption cavities (11); the elastic film layer (2) covers the perforated plate layer I (3) in the positive direction, so that the whole multi-layer sound absorption assembly forms a sealing structure at the top end;
the supporting frame (1) is arranged on the outer side of the multilayer sound absorption assembly in a surrounding mode and is used for clamping and accommodating the flexible multilayer sound absorption assembly;
the fixing assembly comprises a pressing plate (13) and fastening screws (14), wherein the pressing plate (13) comprises a vertical coaming and a horizontal annular pressing ring, the coaming is attached to the inner wall surface of the supporting frame (1), the annular pressing ring is pressed on the upper surface of the elastic film layer (2) far away from the central end, the fastening screws (14) fix the pressing plate (13) on the supporting frame (1) through preset threaded holes on the coaming, and the pressing plate (13) is rigidly connected with the elastic film layer (2) and the supporting frame.
2. A composite broadband sound absorbing structure according to claim 1, wherein: the supporting frame (1) is in a cylindrical structure with openings at the upper end and the lower end.
3. A composite broadband sound absorbing structure according to claim 1 or 2, characterized in that: the sound absorption holes II (6) are uniformly formed in the lower end face of the perforated plate layer II (4), and the hole depth of the sound absorption holes II (6) is continuously increased from the axis line end to the axis line near in the radial direction of the perforated plate layer II (4).
4. A composite broadband sound absorbing structure according to claim 1 or 2, characterized in that: the perforated plate layer I (3) and the perforated plate layer II (4) are flexibly connected.
5. A composite broadband sound absorbing structure according to claim 1 or 2, characterized in that: the supporting frame (1) is made of a hard material.
6. A composite broadband sound absorbing structure according to claim 1 or 2, characterized in that: the height of the support (10) increases from top to bottom in the thickness direction of the perforated plate layer I (3).
7. A composite broadband sound absorbing structure according to claim 1 or 2, characterized in that: the support piece (10) is supported below one end of the perforated plate, which is away from the central through hole I (7).
8. A composite broadband sound absorbing structure according to claim 1 or 2, characterized in that: the sound absorption holes I (12) on each layer of perforated plate are uniformly arranged.
9. A composite broadband sound absorbing structure according to claim 1 or 2, characterized in that: the elastic film layer (2) is glued on the upper surface of the perforated plate layer I (3).
10. A composite broadband sound absorbing structure according to claim 1 or 2, characterized in that: the coaming and the annular pressing ring are of an integrated structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110115532.XA CN112750415B (en) | 2021-01-28 | 2021-01-28 | Composite broadband sound absorption structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110115532.XA CN112750415B (en) | 2021-01-28 | 2021-01-28 | Composite broadband sound absorption structure |
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| CN112750415A CN112750415A (en) | 2021-05-04 |
| CN112750415B true CN112750415B (en) | 2023-10-13 |
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| CN202110115532.XA Active CN112750415B (en) | 2021-01-28 | 2021-01-28 | Composite broadband sound absorption structure |
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| CN (1) | CN112750415B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113643678A (en) * | 2021-07-06 | 2021-11-12 | 洛阳拖拉机研究所有限公司 | Sound absorption and insulation composite structure |
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| CN205211409U (en) * | 2015-12-09 | 2016-05-04 | 北京市劳动保护科学研究所 | Microperforated panel combines super materials compound sound absorbing structure of acoustics |
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| WO2019186970A1 (en) * | 2018-03-29 | 2019-10-03 | ＭＴ－Ｔｅｃ合同会社 | Automobile component |
| CN110588683A (en) * | 2019-08-16 | 2019-12-20 | 哈工大机电工程(嘉善)研究院 | Composite board for low-frequency broadband noise reduction of compartment structure |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6977109B1 (en) * | 1998-07-24 | 2005-12-20 | 3M Innovative Properties Company | Microperforated polymeric film for sound absorption and sound absorber using same |
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2021
- 2021-01-28 CN CN202110115532.XA patent/CN112750415B/en active Active
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US8474574B1 (en) * | 2012-02-29 | 2013-07-02 | Inoac Corporation | Sound absorbing structure |
| CN205211409U (en) * | 2015-12-09 | 2016-05-04 | 北京市劳动保护科学研究所 | Microperforated panel combines super materials compound sound absorbing structure of acoustics |
| CN107401225A (en) * | 2017-09-08 | 2017-11-28 | 北京市劳动保护科学研究所 | The sound absorption and insulation structure that a kind of flexible particle is piled up |
| WO2019186970A1 (en) * | 2018-03-29 | 2019-10-03 | ＭＴ－Ｔｅｃ合同会社 | Automobile component |
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