A composite sound insulation board based on acoustic metamaterial

Abstract

The present invention discloses a composite sound insulation board based on acoustic metamaterials, which is composed of an arrangement and combination of cellular units, and each cellular unit is composed of a micro-perforated plate, a sound absorbing material layer, an acoustic metamaterial plate, a sound absorbing material layer and a micro-perforated plate in a sandwich structure. The composite sound insulation board of the present invention is an insertable sound-absorbing board. The composite sound insulation board is attached to the wall. When the sound wave passes through the composite sound insulation board, the micro-perforated plate and the sound absorbing material layer mainly reduce the medium and high frequency noise. When passing through the acoustic metamaterial plate, the band diagram of the acoustic metamaterial plate is designed to generate local resonance, consume energy to achieve the purpose of noise reduction, and the main action frequency is low frequency. The present invention has a simple structure, occupies a small space, and is easy to operate.

Description

Technical Field

[0001] The invention relates to the technical field of acoustic bag sound insulation, and in particular to a composite sound insulation board based on acoustic metamaterial. Background Art

[0002] With the rapid development of industry, industrial noise pollution has seriously affected people's normal production and life. The oil pumps or generators in the production workshop have unique low-frequency noise. Since the noise wavelength is long, it cannot be simply blocked by a single layer of steel plate, so the low-frequency noise pollution is more serious.

[0003] An important feature of acoustic metamaterials is that they have an acoustic band gap, that is, acoustic metamaterials are functional materials or structures composed of two or more elastic media with periodic structures and elastic band gap characteristics. When sound waves propagate in acoustic metamaterials, they are affected by their internal periodic structures to form special band gaps. The propagation of sound waves in the band gap frequency range is suppressed, so phononic crystals have broad application prospects in noise reduction. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a composite sound insulation board based on acoustic metamaterials.

[0005] The present invention provides the following technical solutions:

[0006] The present invention provides a composite sound insulation board based on acoustic metamaterials. The composite sound insulation board is composed of cell unit structures arranged and connected in a rectangular shape. Each cell unit structure comprises a micro-perforated plate, a sound absorbing material layer and an acoustic metamaterial plate. The sound absorbing material layer and the micro-perforated plate are in a sandwich structure. The cell unit structures are fixedly sealed and connected to form a composite sound insulation board.

[0007] The composite sound insulation board includes a first layer of micro-perforated plate and sound absorbing material layer symmetrically arranged from top to bottom, the sound absorbing material layer is covered on the inner side of the micro-perforated plate, the micro-perforated plate and the sound absorbing material layer are glued together, and the micro-perforated plate is provided with a plurality of through holes in a rectangular array; the acoustic metamaterial plate is in the second layer, each grid of the second layer is provided with a cell unit structure, the cell unit structure is distributed in a rectangular shape, the acoustic metamaterial plate includes a rectangular elastic film and four rectangular mass blocks, the rectangular elastic film is glued and connected with the rectangular mass blocks in the adjacent cell unit structure, the four rectangular mass blocks are evenly distributed on both sides of the elastic film, wherein the long side of the rectangular mass block is parallel to the short side of the elastic film and the distance is 1.5 mm, and is located in the center; the bottom of the acoustic metamaterial plate is provided with the same micro-perforated plate and sound absorbing material layer as the first layer, and the third layer of sound absorbing material layer and micro-perforated plate are symmetrical with the micro-perforated plate and sound absorbing material layer of the first layer about the middle acoustic metamaterial plate;

[0008] That is, the composite sound insulation board comprises a micro-perforated board, a sound absorbing material layer, an acoustic metamaterial board, a sound absorbing material layer and a micro-perforated board from top to bottom.

[0009] As a preferred technical solution of the present invention, the thickness of the micro-perforated plate is 0.5 mm, the perforation rate is 40-50%, the through hole diameter of the micro-perforated plate is 2-4 mm, and the material is ordinary steel.

[0010] As a preferred technical solution of the present invention, the sound absorbing material of the sound absorbing material layer is sound absorbing cotton, and the thickness of the sound absorbing material layer is 10 to 15 mm.

[0011] As a preferred technical solution of the present invention, the rectangular elastic film is a silicone film, and the dimensions of the acoustic metamaterial plate are 30 mm in length, 15 mm in width, and 0.1-0.3 mm in thickness.

[0012] As a preferred technical solution of the present invention, the composite sound insulation board can be assembled from a plurality of cell unit structures according to the actual space size, and the size of the rectangular elastic film can also be customized according to the actual space size. The micro-perforated plates on adjacent cell unit structures need to be connected by seam welding, and the sound absorbing material layer is connected by gluing.

[0013] As a preferred technical solution of the present invention, the rectangular mass block has a length of 12 mm, a width of 6 mm, a thickness of 1 to 2 mm, and is made of ordinary steel.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The noise in the present invention is reduced by 10dB in the low-frequency band (45-55Hz) through the comprehensive effect of the micro-perforated plate, the sound-absorbing material layer and the acoustic metamaterial, and can also be reduced by 20-25dB in the wide frequency band of 100-5000Hz;

[0016] 2. In the present invention, the frequency range of noise reduction can be broadened by increasing the material density of the mass block in the acoustic metamaterial;

[0017] 3. In the present invention, the frequency range of noise reduction can be shifted to low frequency by increasing the mass of the mass block;

[0018] 4. The combination of the micro-perforated plate and the acoustic material layer in the present invention can more fully reduce the energy of high and low frequencies in the sound waves, thereby achieving the effect of noise reduction and sound insulation;

[0019] 5. The composite sound insulation board of the present invention is composed of a plurality of tiny cell unit structures, and can be flexibly adjusted according to the requirements of different spaces while ensuring the sound insulation effect of the cell unit structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 It is a schematic diagram of the structure of the present invention;

[0022] Figure 2 It is a schematic diagram of the cell unit structure of the present invention;

[0023] Figure 3 This is one of the schematic diagrams of the acoustic metamaterial plate of the present invention;

[0024] Figure 4 This is the second schematic diagram of the acoustic metamaterial plate of the present invention;

[0025] Figure 5 A schematic diagram of a micro-perforated plate of the present invention;

[0026] Figure 6 is a schematic diagram of a sound absorbing material layer of the present invention;

[0027] In the figure: 1. Cell unit structure; 2. Micro-perforated plate; 3. Rectangular mass block; 4. Rectangular elastic film; 5. Sound absorbing material layer; 6. Acoustic metamaterial plate. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. The same reference numerals in the accompanying drawings all refer to the same components.

[0029] In addition, if a detailed description of a known technology is not necessary for illustrating the features of the present invention, it will be omitted. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the drawings, and the words "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0030] Example 1

[0031] like Figures 1 to 6As shown, the present invention is a composite sound insulation board based on acoustic metamaterials, and the composite sound insulation board is composed of cell unit structures 1 arranged continuously in a rectangular shape; each cell unit structure 1 is composed of a micro-perforated plate 2, a sound absorbing material layer 5, an acoustic metamaterial plate 6, a sound absorbing material layer 5 and a micro-perforated plate 2 from top to bottom. The cell unit structures 1 need to be sealed to prevent sound leakage. For example, the micro-perforated plates 2 are connected by seam welding, the rectangular elastic film 4 in the acoustic metamaterial plate 6 is connected by adhesive bonding, and the sound absorbing material layers 5 are connected by adhesive bonding, thereby forming a composite sound insulation board. Compared with traditional sound insulation boards, it not only opens up the sound insulation characteristics for low frequencies, but also has better sound insulation performance in medium and high frequencies, achieving a better sound insulation effect;

[0032] The micro-perforated plate 2 and the sound-absorbing material layer 5 are connected by gluing. The sound-absorbing material of the sound-absorbing material layer 5 is sound-absorbing cotton. The thickness of the sound-absorbing material layer 5 is 10-15 mm. The micro-perforated plate 2 is provided with a plurality of through holes 7 distributed in a rectangular array. The thickness of the micro-perforated plate 2 is 0.4-0.8 mm. The perforation rate is 40-50%. The aperture of the through holes 7 of the micro-perforated plate 2 is 2-4 mm. The material is ordinary steel. The size of the micro-perforated plate 2 is the same as that of the composite sound insulation plate 1. The micro-perforated plate 2 is used to control the frequency spectrum performance of the composite sound insulation plate by selecting different perforation rates and hole depths of different plate thicknesses, so that it can obtain a good sound insulation effect within a required frequency range.

[0033] The composite sound insulation board includes a micro-perforated plate 2, a sound absorbing material layer 5 and an acoustic metamaterial plate 6, etc. The acoustic metamaterial plate 6 includes a rectangular elastic film 4 and four rectangular mass blocks 3. The rectangular elastic film 4 is bonded to the rectangular elastic film 4 in the adjacent cell unit structure 1. The four rectangular mass blocks 3 are evenly distributed on both sides of the rectangular elastic film 4, wherein the long side of the rectangular mass block 3 is parallel to the short side of the rectangular elastic film 4 and the distance is 1.5 mm, and they are located in the center. The rectangular elastic film 4 is a rectangular silicone film, and the size of a single cell is 30 mm long, 15 mm wide, and 0.1-0.3 mm thick; the mass block is rectangular, 12 mm long, 6 mm wide, and 1-2 mm thick, and the material is ordinary steel.

[0034] Each cell unit structure 1 in the present invention is provided with two pairs of micro-perforated plates 2 and sound-absorbing material layers 5, which are respectively arranged on both sides of the acoustic metamaterial plate 6 and form a symmetry. The noise sound waves pass through the micro-perforated plates 2, the sound-absorbing material layer 5 and the acoustic metamaterial plate 6 of the composite sound insulation board, which not only reduces the sound pressure level of the noise source in the low-frequency band (45-55Hz) by 10dB, but also reduces it by 20-25dB in the wide frequency band of 100-5000Hz; if the material density of the rectangular mass block 3 in the acoustic metamaterial plate 6 is increased, the frequency range of noise reduction is widened. The frequency range of noise reduction can also be shifted to the low-frequency band by increasing the mass of the rectangular mass block 3.

[0035] The composite sound insulation board can be directly placed in the space where sound insulation is required to achieve the purpose of noise reduction, and the installation is convenient; when the sound wave passes through the composite sound insulation board, the micro-perforated plate 2 and the sound absorbing material layer 5 mainly reduce the medium and high frequency noise; when passing through the acoustic metamaterial plate 6, it is affected by the elastic film 4 and the rectangular mass block 3 structure, generating local resonance, consuming energy to achieve the purpose of noise reduction, and the main action frequency is low frequency.

[0036] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A composite sound insulation board based on acoustic metamaterial, characterized in that: The composite sound insulation board is composed of cell unit structures (1) arranged and connected in a rectangular shape, each cell unit structure (1) comprising a micro-perforated plate (2), a sound absorbing material layer (5) and an acoustic metamaterial plate (6), the sound absorbing material layer (5) and the micro-perforated plate (2) forming a sandwich structure, and the cell unit structures (1) are fixedly sealed and connected to each other, thereby forming a composite sound insulation board; The composite sound insulation board comprises a first layer of a micro-perforated plate (2) and a sound absorbing material layer (5) which are symmetrically arranged from top to bottom, the sound absorbing material layer (5) covering the inner side of the micro-perforated plate (2), the micro-perforated plate (2) and the sound absorbing material layer (5) being glued together, and the micro-perforated plate (2) is provided with a plurality of through holes in a rectangular array; the acoustic metamaterial plate (6) is in the second layer, each grid of the second layer is provided with a cell unit structure (1), the cell unit structure (1) is distributed in a rectangular shape, the acoustic metamaterial plate (6) comprises a rectangular elastic film (4) and four rectangular mass blocks (3), the rectangular elastic film (4) and the sound absorbing material layer (5) are glued together, and the micro-perforated plate (2) is provided with a plurality of through holes in a rectangular array; The film (4) is adhesively connected to the rectangular mass blocks (3) in the adjacent cell unit structure (1), wherein the four rectangular mass blocks (3) are evenly distributed on both sides of the rectangular elastic film (4), wherein the long sides of the rectangular mass blocks (3) are parallel to the short sides of the rectangular elastic film (4) and the distance is 1.5 mm, and they are located at the center; the bottom of the acoustic metamaterial plate (6) is provided with a micro-perforated plate (2) and a sound absorbing material layer (5) that are the same as those of the first layer, and the sound absorbing material layer (5) and the micro-perforated plate (2) of the third layer are symmetrical with the micro-perforated plate (2) and the sound absorbing material layer (5) of the first layer about the middle acoustic metamaterial plate (6); That is, the composite sound insulation board comprises, from top to bottom, a micro-perforated board (2), a sound absorbing material layer (5), an acoustic metamaterial board (6), a sound absorbing material layer (5), and a micro-perforated board (2).

2. The composite sound insulation board based on acoustic metamaterial according to claim 1, characterized in that: The thickness of the micro-perforated plate (2) is 0.5 mm, the perforation rate is 40-50%, the diameter of the through-holes of the micro-perforated plate (2) is 2-4 mm, and the material is ordinary steel.

3. The composite sound insulation board based on acoustic metamaterial according to claim 1, characterized in that: The sound absorbing material of the sound absorbing material layer (5) is sound absorbing cotton, and the thickness of the sound absorbing material layer (5) is 10 to 15 mm.

4. The composite sound insulation board based on acoustic metamaterial according to claim 1, characterized in that: The rectangular elastic film (4) is a silicone film, and the acoustic metamaterial plate (6) has dimensions of 30 mm in length, 15 mm in width, and 0.1 to 0.3 mm in thickness.

5. A composite sound insulation board based on acoustic metamaterial according to any one of claims 1 to 4, characterized in that: The composite sound insulation board is assembled from a plurality of cell unit structures (1) according to the actual space size, and the size of the rectangular elastic film (4) is customized according to the actual space size. The micro-perforated plates (2) on adjacent cell unit structures (1) need to be connected by seam welding, and the sound absorbing material layer (5) is connected by gluing.

6. The composite sound insulation board based on acoustic metamaterial according to claim 1, characterized in that: The rectangular mass block (3) has a length of 12 mm, a width of 6 mm, a thickness of 1 to 2 mm, and is made of ordinary steel.

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