Nonmetal acoustic board

Abstract

The invention provides a non-metal acoustic board which comprises a shell and a sound absorber located in the shell, the shell comprises a panel (11), a back plate (12), an upper side plate (13) and a lower side plate (14), an opening cavity is formed in the side close to the panel (11), the opening cavity comprises a first layer cavity and a second layer cavity, and the first layer cavity is communicated with the second layer cavity. The first-layer cavity is located between the panel and the second-layer cavity, and openings in the open cavities all penetrate through the panel. The non-metal acoustic board is large in cavity inner area, large in cavity number, light in weight, high in strength and high in sound absorption coefficient.

Description

Technical Field

[0001] The invention relates to a noise protection device, in particular to a non-metallic sound absorbing board. Background Art

[0002] Inserting a facility between the sound source and the receiver, so that the sound wave propagation has a significant additional attenuation, thereby reducing the noise impact in a certain area where the receiver is located, such a facility is called a sound barrier. Sound barriers are divided into traffic sound barriers, equipment noise attenuation sound barriers, and industrial plant boundary sound barriers. Highways and expressways are the places where various types of sound barriers are used most.

[0003] The sound barrier is assembled from sound barrier unit panels. The sound barrier unit panels are generally composed of an outer shell and a sound-absorbing material inside the outer shell. Depending on the material, the sound barrier unit panels can be divided into metal sound barrier unit panels, non-metal sound barrier unit panels and transparent sound barrier unit panels. Non-metal sound barrier unit panels have been widely used for their economical appearance and easy design. However, the existing non-metal sound barrier unit panels generally have the problem of low sound absorption coefficient, and the structural strength needs to be improved. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a non-metallic sound absorbing board.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: A non-metallic sound absorbing panel comprises an outer shell and a sound absorbing body located in the outer shell, wherein the outer shell comprises a panel, a back plate, an upper side plate and a lower side plate, an open cavity is arranged near the panel side, the open cavity comprises a first layer cavity and a second layer cavity, the first layer cavity is located between the panel and the second layer cavity, and the openings on the open cavity all penetrate the panel.

[0006] Preferably, the first layer of cavities includes one or several independent sub-cavities, and the second layer of cavities includes one or several independent sub-cavities.

[0007] Preferably, a closed cavity is further provided between the back plate and the second layer of cavity.

[0008] Preferably, the closed cavity includes one or several independent sub-cavities.

[0009] Preferably, the first layer of cavities includes a plurality of independent sub-cavities, the second layer of cavities includes a plurality of independent sub-cavities, and the openings of the sub-cavities of the second layer of cavities are spaced apart from the openings of the sub-cavities of the first layer of cavities.

[0010] Preferably, the first layer of cavities includes a plurality of independent sub-cavities, the second layer of cavities includes a sub-cavity provided with a plurality of openings, and the openings on the sub-cavities of the second layer of cavities are provided between the sub-cavities of the first layer of cavities.

[0011] Preferably, the sub-cavities on the first layer of cavities and the sub-cavities on the second layer of cavities are different in size.

[0012] Preferably, the sub-cavity is a columnar sub-cavity extending along the panel, and the opening is a slit extending along the panel.

[0013] Preferably, one or more passivation wedges are provided on the inner wall of the opening on the sub-cavity, and the passivation wedges are columnar wedges extending along the panel.

[0014] Preferably, the panel layer has a thickness of 1.5 cm to 3 cm, and the back panel layer has a thickness of 1 cm to 3 cm.

[0015] Preferably, the non-metallic sound absorbing panel is formed by integrally extruding ECP material.

[0016] The beneficial effects of the present invention are as follows: the non-metallic sound absorbing board provided by the present invention, firstly, by arranging three layers of cavities inside the non-metallic sound absorbing board, the first layer of open cavities and the second layer of open cavities greatly increase the effective sound absorbing area of ​​the non-metallic sound absorbing board, so that the effective sound absorbing area of ​​the non-metallic sound absorbing board reaches twice the area of ​​the non-metallic sound absorbing board facing the incident sound wave, and the sound absorption coefficient is effectively improved; secondly, from a structural point of view, more porous sound absorbing materials can be placed in the structure of the double-layer open cavities, which effectively improves the space structure utilization rate inside the non-metallic sound absorbing board; thirdly, by designing the first layer of open cavities and the second layer of open cavities of different sizes, different sound absorption resonance frequencies are generated, and the sound absorption range is broadened, which can be used for different The noise of low frequency can be reduced in a targeted manner; fourthly, the closed cavity on the back panel side can not only reduce the overall weight of the non-metallic sound-absorbing board, but also form a drum-like structure with the non-metallic sound-absorbing board to form a resonance structure, which can effectively reduce low-frequency noise; fifthly, the blunted wedge set in the open cavity can increase the number of reflections of the sound wave in the cavity. Each time it is reflected, the multi-hole sound-absorbing material will absorb the sound wave once, so the number of reflections is proportional to the sound absorption of the built-in porous sound-absorbing material, and the blunted wedge can also be used as a limiter to limit the position of the built-in sound-absorbing material polyester fiber board so that it is fixed and does not move. This structure does not require the addition of auxiliary components to fix the position of the polyester fiber board, and the structure is simple and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the overall structure of a sound barrier composed of non-metallic sound absorbing panels according to an embodiment of the present invention; Figure 2This is a schematic diagram of the overall structure of a non-metallic sound absorbing panel according to an embodiment of the present invention; Figure 3 for Figure 2 Schematic diagram of the cross-sectional structure. Implementation

[0018] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0019] like Figure 1 , 2 As shown in Figure 3, an embodiment of the present invention provides a non-metallic sound absorbing board. The non-metallic sound absorbing board is generally made of cement material and can be integrally formed by casting, extrusion, etc., or assembled by a combination of methods. The sound absorbing board in this embodiment is integrally cast by ECP material.

[0020] The non-metallic sound absorbing panel includes an outer shell and a sound absorbing body located in the outer shell. The outer shell is a shell containing a cavity structure. The outer shell includes a panel 11, a back panel 12, an upper side panel 13 and a lower side panel 14. The thickness of the panel 11 is generally selected to be between 1.5 cm and 3 cm, and the thickness of the back panel 12 is generally selected to be between 1 cm and 3 cm. An open cavity is arranged near the panel 11. The open cavity includes a first layer of cavity and a second layer of cavity. The first layer of cavity is located between the panel 11 and the second layer of cavity. The openings on the open cavity all pass through the above-mentioned panel. The thickness of the first layer of cavity and the second layer of cavity is generally selected to be between 1 cm and 5 cm. The cavity can be selected as a cylindrical cavity extending along the panel or an independent cavity one by one. As a specific option, the first layer of cavity includes one or several independent sub-cavities, and the second layer of cavity includes one or several independent sub-cavities. Specifically, the first layer of cavity includes several independent cylindrical sub-cavities extending along the panel, and the second layer of cavity includes several independent cylindrical sub-cavities extending along the panel. The opening of the cavity is a slit, which extends laterally along the panel. The opening of the sub-cavity of the second layer of cavity and the opening of the sub-cavity of the first layer of cavity are arranged at intervals. The size of each cavity can be selected to be the same or different. The space in each sub-cavity forms an independent air column. The air column in the sub-cavity and the sub-cavity constitute a vibration system. When noise reaches the non-metallic sound-absorbing plate, the noise enters the cavity from the opening. When the frequency of the incident sound wave is close to the natural frequency of the system, resonance occurs and an absorption peak occurs. The cavity volume is different, and the resonance sound absorption frequency is also different accordingly. Therefore, the more types of cavity volumes, the wider the resonance sound absorption frequency band, the more cavities, the larger the specific surface area inside the cavity, and the more obvious the noise reduction effect. Compared with the traditional non-metallic sound-absorbing plate containing only one large cavity, the structural design of this double-layer cavity increases the number of cavities and the specific surface area inside the cavity by 1.8 to 3 times.

[0021] The sound absorber is arranged in the open cavity of the non-metallic sound absorbing board. The sound absorber is generally made of porous materials, such as glass wool or rock wool. The sound absorber in this embodiment is made of porous polyester fiber board. The polyester fiber board can be a flat plate structure or a three-dimensional structure. As a preferred solution, Figure 3 As shown, in this embodiment, the polyester fiber board is designed to be a V-shaped bending structure, which is inserted in the cylindrical open cavity and is fixed at three points with the inner wall of the open cavity. The structure is stable and not easy to slide or fall out. For the multi-hole sound-absorbing material, under the premise of the same surface density, the sound absorption coefficient of the multi-hole sound-absorbing material is proportional to its surface area. The V-shaped bending structure increases the surface area of ​​the polyester fiber board and also increases the sound absorption of the overall structure. An additional cavity is formed between the back of the V-shaped bending structure and the inner wall of the open cavity. Compared with the flat polyester fiber board, the additional cavity increases the refraction of sound and effectively improves the sound absorption coefficient.

[0022] In order to further improve the sound absorption coefficient, a blunt wedge is provided on the inner wall of the opening located on the open cavity. When the open cavity is a cylindrical cavity extending along the panel, the blunt wedge structure is a corresponding columnar wedge extending along the panel. The wedge can be designed to be one, two or more. This structure can increase the specific surface area in the cavity, increase the amount of sound wave convergence and incidence, and use the "reflection" of sound to concentrate the sound to propagate forward instead of reflecting it back again, thereby effectively improving the sound absorption performance. The blunt wedge structure can also fix the polyester fiberboard with a V-shaped bend structure without adding other fixing structures.

[0023] In order to further improve the anti-seismic and noise reduction performance of the non-metallic sound-absorbing board, a closed cavity is also arranged between the back plate and the second layer of cavity. The arrangement of the closed cavity greatly reduces the weight of the non-metallic sound-absorbing board. The closed cavity can be one or more. Specifically, the closed cavity can be selected as one or more cylindrical closed cavities extending along the panel or independent closed cavities. The closed cavity also forms a drum-shaped structure with the non-metallic sound-absorbing board, and can form an overall resonance structure. This resonance structure has a good absorption and noise reduction effect on low-frequency noise, and can effectively reduce low-frequency noise.

[0024] Through the structural design of the three-layer cavity in the above embodiment, the volume of the cavity occupies more than 50% of the total volume of the non-metallic sound absorbing board. These cavities not only greatly reduce the overall weight of the non-metallic sound absorbing board, but the hollow structure also greatly increases the structural strength of the non-metallic sound absorbing board, which facilitates transportation and installation.

[0025] After comparative testing, compared with traditional non-metallic sound-absorbing panels, the overall sound absorption coefficient of the above three-layer cavity non-metallic sound-absorbing panel structure is improved by 15~25%.

[0026] The embodiment described above is only one of the more preferred specific implementations of the present invention. Common changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. A non-metallic sound absorbing panel, comprising a shell and a sound absorbing body located in the shell, wherein the shell comprises a face plate (11), a back plate (12), an upper side plate (13) and a lower side plate (14), and an open cavity is arranged near the face plate (11), characterized in that: The open cavity comprises a first layer of cavities and a second layer of cavities, the first layer of cavities is located between the panel and the second layer of cavities, and the openings on the open cavities all penetrate the panel.

2. The non-metallic sound absorbing panel according to claim 1, characterized in that: The first layer of cavities includes one or more independent sub-cavities, and the second layer of cavities includes one or more independent sub-cavities.

3. The non-metallic sound absorbing board according to claim 1, characterized in that: A closed cavity is also provided between the back plate and the second layer of cavity.

4. The non-metallic sound absorbing board according to claim 3, characterized in that: The closed cavity includes one or more independent sub-cavities.

5. The non-metallic sound absorbing panel according to claim 1, characterized in that: The first layer of cavities includes a plurality of independent sub-cavities, the second layer of cavities includes a plurality of independent sub-cavities, and the openings of the sub-cavities of the second layer of cavities are spaced apart from the openings of the sub-cavities of the first layer of cavities.

6. The non-metallic sound absorbing board according to claim 5, characterized in that: The sub-cavity is a columnar sub-cavity extending along the panel, and the opening is a slit extending along the panel.

7. The non-metallic sound absorbing board according to claim 6, characterized in that: One or more passivation wedges are arranged on the inner wall of the opening on the sub-cavity, and the passivation wedges are columnar wedges extending along the panel.

8. The non-metallic sound absorbing board according to claim 5, characterized in that: The sub-cavities on the first cavity layer and the sub-cavities on the second cavity layer have different sizes.

9. The non-metallic sound absorbing panel according to claim 1, characterized in that: The thickness of the panel layer is 1.5 cm to 3 cm, and the thickness of the back panel layer is 1 cm to 3 cm.

10. The non-metallic sound absorbing panel according to claim 1, characterized in that: The non-metallic sound absorbing panel is formed by integral extrusion of ECP material.

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