JP2002201613A - Transparent sound absorbing body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent sound absorbing body capable of effectively absorbing noise generated on railroad and highway without blocking light. SOLUTION: This transparent sound absorbing body 1 is provided with a transparent panel member 2 allowing light transmit and sound absorbing members 3 joined, leaving light transmission regions 4 on the surface of the transparent panel member 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-transmitting sound absorber that effectively absorbs noise generated on railways, highways, and the like and does not block light.

[0002]

2. Description of the Related Art With the development of a highway network and a high-speed railway network as social capital development, reduction of traffic noise as a living environment along the road is required. One of the most effective countermeasures at present is to install sound-absorbing and sound-insulating walls.

Hitherto, for example, a glass fiber laminate has been widely used as the sound absorbing and insulating wall. In this case, various measures have been taken in order to prevent moisture from invading into the gaps between the fiber laminated molded articles due to rainfall or the like and to reduce the sound absorption coefficient of the fiber laminated molded articles. For example, in order to prevent infiltration of moisture, the surface of the fiber molded body is covered with a water-repellent film or the like, or glass wool or rock wool is put in a bag of a fluororesin film (eg, PVF, ETFE, etc.). Had been Also,
Measures have also been taken, such as storing the fiber laminate molded product in an aluminum box having an opening provided on the noise input surface side by punching, a louver, or the like. Furthermore, in recent years, a sound-absorbing material of an organic fiber laminated molded article which can prevent infiltration of moisture and has excellent sound-absorbing performance has been developed.

[0004]

However, since the conventional sound absorbing and insulating wall does not transmit light such as sunlight, the surrounding scenery is not known at all while traveling on a highway or the like, so that it is difficult to travel through a tunnel. There was a feeling of oppression like this. There was also a problem that private houses around the road complained about the right to sunshine.

On the other hand, when a light-transmitting plastic board is used for the sound-absorbing and sound-absorbing wall, the board has no sound-absorbing effect, so that vehicle noise reverberates on the road.
In some cases, the noise reduction effect was not obtained at the private houses as much as expected.

There have also been proposed some assembling structures of light-transmitting and sound-absorbing panels (for example, see Japanese Patent No. 306).
No. 9770), which is not always sufficient in terms of the sound absorbing effect.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a light-transmitting sound absorber that effectively absorbs noise generated on railways, highways, and the like and does not block light.

[0008]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have combined a light-transmitting panel member that transmits light and a sound-absorbing material made of a fiber molding under specific conditions. As a result, they have found that the above object can be achieved, and have completed the present invention. That is, the present invention is as described below.

<1> A light-transmitting sound absorber comprising: a light-transmitting panel member that transmits light; and a sound-absorbing material joined to a surface of the light-transmitting panel member while leaving a light-transmitting region. is there.

<2> In the light-transmitting sound absorber according to the item <1>, a plurality of the sound-absorbing materials are alternately arranged in a strip shape in a lateral direction on a surface of the light-transmitting panel member and a light-transmitting region. It is.

<3> The light-transmitting sound absorber according to <1>, wherein a plurality of the sound-absorbing materials are alternately arranged in a strip shape in a longitudinal direction on the surface of the light-transmitting panel member and in a light-transmitting region. It is.

<4> The light-transmitting sound absorber according to <1>, wherein the sound-absorbing material is arranged in a wave shape on the surface of the light-transmitting panel member.

<5> In the light-transmitting sound absorber of the above <1>, the sound absorbing material has a plate-shaped fiber molded body having a plurality of large-diameter through holes and a plurality of small-diameter through holes covering the surface thereof. It is a light-transmitting sound absorber made of a sheet-like transparent protective material.

<6> In the light-transmitting sound absorber of the above <1>, the sound absorbing material comprises a plurality of donut-shaped fiber molded bodies and a sheet-shaped transparent protective material having a plurality of small-diameter through holes covering the surface thereof. It is a translucent sound absorber.

<7> In the light-transmitting sound absorber according to any one of <1> to <6>, the light-transmitting panel member is a light-transmitting sound absorber made of polycarbonate or acrylic resin.

<8> In the light-transmitting sound absorber according to any one of <5> to <7>, the fiber molded body is a light-transmitting sound absorber made of a polyester-based organic fiber.

<9> In the light-transmitting sound absorber according to any one of <1> to <8>, the light-transmitting region of the light-transmitting panel member is a light-transmitting sound absorber in which a concave lens is formed.

The light-transmitting sound absorber of the present invention described in <1> to <9> can effectively absorb noise generated on railways, highways, and the like without blocking light. Also, <
In the inventions of 2> to <4>, it is possible to confirm a distant landscape during high-speed traveling, and particularly to <3> and <4>.
In 4>, it is possible to confirm a distant landscape without worrying about the sound absorbing material in front due to the afterimage effect. <5>
In the inventions of <6> and <6>, a sufficient sound absorbing effect can be obtained while allowing light transmission. Further, in the invention of the above <7>, an effect excellent in translucency and weather resistance is exhibited. Furthermore, in the invention of the above <8>, an effect particularly excellent in sound absorption is exhibited. Furthermore, the above <9>
According to the invention, the transmitted light is diffused by the action of the concave lens formed in the light transmitting area, and the shadow of the pattern of the sound absorbing material can be eliminated. As a result, it is possible to eliminate the sunshine problem of residents and the adverse effect on driving.

[0019]

Embodiments of the present invention will be described below. FIG. 1 shows a translucent sound absorber 1 according to one embodiment of the present invention. As shown in FIG.
In the first embodiment, a plurality of sound absorbing members 3 are alternately arranged in a strip shape in the lateral direction on the surface of the light transmitting panel member 2 with the light transmitting regions 4. The light-transmitting panel member 2 is preferably a plastic board, and particularly preferably a polycarbonate or acrylic resin board in terms of light-transmitting properties, durability and weather resistance.

The spacing between the sound absorbing members 3 and the volume of each sound absorbing member 3 may be appropriately determined according to the application location of the translucent sound absorbing body. For example, when emphasis is placed on the sound absorbing effect, light transmission is required. The area 4 may be a minimum area capable of daylighting, and the number of the sound absorbing materials 3 or the volume thereof may be increased accordingly. Further, the height at which noise is generated or the height of daylighting may be considered, and the number of the sound absorbing materials 3 to be applied may be determined accordingly. For example, to increase the amount of light collected from the upper part of the translucent sound absorbing body 1 and to enhance the sound absorbing effect in the lower part,
The interval between the sound absorbing members 3 may be reduced at the upper portion, and the interval between the sound absorbing members 3 may be increased at the lower portion. The type of the sound absorbing material 3 is not particularly limited, and a foam or a fiber molded product can be used.

The sound absorbing material 3 as a preferred example is made of a fiber molded body covered with a protective material, and a nonwoven fabric made of organic fibers can be suitably used as the protective material. As such an organic fiber nonwoven fabric, a material made of fibers such as polyester, polypropylene, nylon, acrylic, and vinylidene chloride can be suitably used. These organic fibers are hardly degraded even by ultraviolet rays or intrusion of water from the outside, and exhibit long-term outdoor sound absorption performance stably. In view of such performance, a polyester fiber is particularly preferable.

The center of the fineness distribution of the organic fiber nonwoven fabric is preferably 0.5 to 1 from the viewpoint of sound absorbing performance and cost.
It is 0 denier. The basis weight of the nonwoven fabric is preferably 50 to 500 g in order to obtain good sound absorbing performance.
/ M ² .

The organic fiber nonwoven fabric comprises a plurality of organic fibers having different melting points, and the fibers are opened to form a web. The web is heated at a high temperature for a short time to melt the low-melting organic fibers. Then, the high melting point web fibers can be bonded to each other. Further, a water repellent treatment, a disaster prevention treatment, a salt prevention treatment, a weather resistance improvement treatment and the like may be performed according to a conventional method.

In place of the above-described protective material, the entire surface of the fiber molded body may be directly subjected to a water-repellent treatment according to a conventional method. Alternatively, in the sound absorbing material 3 shown in FIG. 1, only the water-repellent treatment may be directly applied to the cross-sections at both ends, and the other surfaces may be entirely covered with the protective material.

[0025] The fiber molded article that can be used in the present invention is:
Preferably, the center of the fiber diameter distribution is 30 deniers or less.
More preferably 10 denier or less, even more preferably
Average apparent density using fiber of 6 denier or less as material
0.01 to 0.15 g / cm^Three, Preferably 0.01 to
0.10g / cm^Three, More preferably 0.02 to 0.0
7g / cm^ThreeOf the fiber assembly.
Uses fine fibers of 30 denier or less and is apparently dense.
By keeping the temperature within the specified range, the ventilation resistance inside the fiber
The resistance can be increased and the sound absorption characteristics can be improved. Temporary
The same appearance when using more than 30 denier fiber
The density becomes coarse, the ventilation resistance does not increase,
The sound characteristics are inferior. On the other hand, this apparent density
If you try to improve sound absorption simply by increasing the
It becomes too easy to radiate sound, and on the contrary, soundproofing performance decreases
I do. From the above, the upper limit of the apparent density is 0.15 g
/ Cm ^ThreeIt is preferable to set 3
Even when using fine fibers of 0 denier or less, the apparent density is
0.01 g / cm^ThreeIf it is smaller, the airflow resistance will increase.
The sound absorption performance cannot be expected, and the soundproofing performance is insufficient.
Minutes. As described above, the fibers used are basically 30 deniers.
And 10 denier to achieve high sound absorption performance.
Fibers, preferably 6 denier or less
Is desirable.

As the material of the fiber, for example, in addition to synthetic fibers such as polyester, polypropylene, polyethylene, nylon and vinylon, natural fibers such as wool, cotton, hemp and metal fibers such as aluminum can also be used.
Further, a fiber opened from a cloth using these fibers can also be used. In this case, bituminous or similar material is made into a fiber by melt spinning or other methods, and this is mixed with the above-mentioned fiber by 10% by weight or more, or a molded article of a fiber aggregate used alone is used. By using it, a large sound absorbing effect can be obtained.

The fibrous molded article contains a binder and is preliminarily formed into a flat plate with an apparent density of 0.025 g / cm ^3.
A desired shape can be obtained by laying the following fiber assembly (preliminary molded body) in a mold and subjecting it to heat compression molding so that the volume becomes 1/2 to 1/4.
As such a preform, a polyester fiber which is hardened with a binder such as polyethylene fiber, low melting point polyester fiber or bituminous fiber can be used. When a fiber molded article is obtained by compression molding this preform, if the compression ratio is less than 2, the air permeability becomes too large and the sound absorption is low, and if the compression ratio is more than 4, an overcompressed portion occurs,
For the reasons described above, the soundproof performance becomes insufficient. Therefore, the compression ratio is preferably from 2 to 4.

The fiber molded body can be obtained by the various molding methods as described above. However, in order to perform a more uniform filling and to reduce the density distribution, the fiber which has been opened and separated is converted into a gas ( It is preferable to employ a method in which the air is blown into the mold together with the air, only this air is exhausted from a large number of mesh holes, and only the fibers are filled into the mold and molded. By such an air-conveying filling method, a free-form filling can be performed, and a uniform, soft, porous material can be obtained as a whole.

In order to solidify the thus obtained filler, a binder is required. As the binder, various materials such as a phenol resin that is heated and melted and solidified by reaction or a urethane-based adhesive that solidifies by reaction with steam are considered, but a binder having a fibrous form can be suitably used. . As such a fibrous binder, a polyester fiber having a low melting point which is melted by heating or steam, or a fiber of polyethylene or polypropylene which is melted by heating and solidified by cooling can be used. Desirably, the fiber material is composed of a low-melting component and a high-melting component, and a composite fiber in which the low-melting component is disposed outside the high-melting component, that is, the fiber surface, from the viewpoint of durability and acoustic performance. It is convenient. That is, if the conjugate fiber is heat-molded at a temperature higher than the melting point of the low-melting component and lower than the melting point of the high-melting component, the binder fibers can be bonded together by melting the low-melting component while maintaining a perfect fiber state. And sound performance can be secured.

In addition, other materials may be used as long as they are in the form of fibers such as bituminous fibers and are melted by heating or the like. As a molding method in which a fibrous binder is mixed, a method in which a mold temperature is adjusted to be equal to or lower than the melting point of the binder and the binder is melted by blowing hot air or steam at a temperature equal to or higher than the melting point to form a fibrous molded body. desirable. In this case, if a means for switching between hot air and cold air is added, the forming cycle can be further improved. Further, by blowing hot air or the like, uniform melting and hardening can be performed even inside the fiber molded body.

As described above, the fibers as the raw material are blown into the mold together with the fibrous binder, and further the hot air is blown to melt the binder so that the fibers are bonded to each other. A molded article can be obtained. By using such a fiber molded body, dimensional accuracy is high and sound insulation performance is excellent.

In order to join the sound absorbing material 3 formed by covering the fiber molded body with the protective material to the translucent panel member 2, any method such as heat fusion or use of an adhesive may be used.
The method based on heat fusion is preferable from the viewpoints of adhesiveness, economy and the like. In addition, about such a fiber molded body, a protective material, a water-repellent treatment, etc., it can be similarly applied in the following suitable examples.

FIG. 2 shows a translucent sound absorber 11 according to another embodiment of the present invention. As shown in the figure, in the light-transmitting sound absorber 11, a plurality of sound-absorbing materials 13 are alternately arranged in a strip shape in the longitudinal direction of the surface of the light-transmitting panel member 12 with the light transmitting regions 14.

The distance between the sound absorbing members 13 and the volume of one sound absorbing member 13 may be appropriately determined according to the application location of the light-transmitting sound absorbing member 11 as in the case of the above-described preferred embodiment. When the sound absorbing material 13 is arranged in the vertical direction, it is not possible for a vehicle running at a high speed to recognize each of them, so that it is possible to satisfactorily recognize a distant scenery due to an afterimage effect.

FIG. 3 shows a translucent sound absorber 21 according to still another embodiment of the present invention. As shown in the figure, in the translucent sound absorbing body 21, the sound absorbing material 23 is arranged on the surface of the translucent panel member 22 in a wave shape. As a result, the light transmission region 2
4 will also be present in the waveform.

The wavelength and the wave height of the waveform of the sound absorbing material 23 may be appropriately determined according to the application location of the light transmitting type sound absorbing body 21 as in the case of the above-described preferred embodiment. Also, when the sound absorbing material 23 has a waveform, an afterimage effect can be obtained in the same manner as in the preferred embodiment described above.

FIG. 4 shows a translucent sound absorber 31 according to still another embodiment of the present invention. FIG. 5 shows a cross-sectional structure of the translucent sound absorber 31. This translucent sound absorber 31
Is a sound absorbing material 33 laminated on the surface of the light transmitting panel member 32.
Is a plate-shaped fiber molded body 35 having a plurality of large-diameter through holes.
And a sheet-like transparent protective material 36 having a plurality of small-diameter through holes covering the surface thereof. With such a structure, a sufficient sound absorbing effect can be obtained and the light transmitting region 3
Lighting from 4 is also possible. In order to join the fiber molded body 35 to the translucent panel member 32 and the sheet-like transparent protective material 36, any method such as heat fusion or use of an adhesive may be used.

FIG. 6 shows a translucent sound absorber 41 according to still another embodiment of the present invention. This translucent sound absorber 41 is
A plurality of donut-shaped fiber moldings 45 are adhered to the surface of the light-transmitting panel member 42 by heat fusion or an adhesive, and the transparent protective material 4 similar to that of the preferred embodiment shown in FIG.
6 are joined. Even in such a structure, a sufficient sound absorbing effect can be obtained, and good lighting can be obtained.

FIG. 7 shows a translucent sound absorber 51 according to still another embodiment of the present invention. This translucent sound absorber 51 is
The arrangement of the sound absorbing material 53 shown in FIG. 1 is basically the same, but differs in that the light transmitting area 54 of the light transmitting panel member 52 forms a concave lens. Since the light transmitting area 54 of the light transmitting panel member 52 forms a concave lens, the transmitted light is diffused,
As shown in FIG. 8, the shadow 57 of the sound absorbing material 53 can be eliminated. The distance D ₂ of the focal point P is changed by varying the curvature of the concave lens, the length D ₁ of the shadow 57 due to this variation. Therefore, the curvature of the concave lens may be appropriately determined according to the application location of the translucent sound absorbing body 51.

The application of the concave lens to the transmission region is possible for the above-mentioned various preferred examples of the light-transmitting sound absorbers. For example, when the concave lens is applied to the light-transmitting sound absorber shown in FIG. 5, FIG. A light-absorbing sound absorber 61 shown in FIG. In this case, the shadow 67 of the sound absorbing material 65 is eliminated by the diffusion of the transmitted light due to the action of the concave lens formed on the light transmitting panel member 62.

As described above, by eliminating the shadow of the pattern of the sound absorbing material, it is possible to eliminate the sunshine problem of the residents and the adverse effect on driving.

[0042]

As described above, according to the translucent sound absorbing body of the present invention, it is possible to effectively absorb noise generated on railways, highways, and the like, and to transmit light. It is possible to avoid problems such as sunshine and driver stress.

[Brief description of the drawings]

FIG. 1 is a perspective view of a translucent sound absorbing body according to an embodiment of the present invention.

FIG. 2 is a perspective view of a translucent sound absorbing body according to another embodiment of the present invention.

FIG. 3 is a perspective view of a translucent sound absorber according to still another embodiment of the present invention.

FIG. 4 is an exploded perspective view of a light-transmitting sound absorber according to still another embodiment of the present invention.

FIG. 5 is a cross-sectional view of the translucent sound absorbing body shown in FIG.

FIG. 6 is an exploded perspective view of a translucent sound absorber according to still another embodiment of the present invention.

FIG. 7 is a perspective view of a translucent sound absorbing body according to still another embodiment of the present invention.

FIG. 8 is an explanatory diagram showing an operation of a concave lens in a light transmission region.

FIG. 9 is a cross-sectional view of a translucent sound absorber according to still another embodiment of the present invention.

[Explanation of symbols]

1, 11, 21, 31, 41, 51, 61 Translucent sound absorber 2, 12, 22, 32, 42, 52, 62 Translucent panel members 3, 13, 23, 33, 53 Sound absorbing materials 4, 14, 24, 34, 54 Light transmission area 35, 45, 65 Fiber molded body 36, 46 Transparent protective material 57, 67 Shadow

Claims (9)

[Claims] 1. A light-transmitting sound absorber comprising: a light-transmitting panel member that transmits light; and a sound-absorbing material joined to a surface of the light-transmitting panel member while leaving a light-transmitting region. 2. The translucent sound absorber according to claim 1, wherein a plurality of said sound absorbing members are alternately arranged in a strip shape in a lateral direction on a surface of said translucent panel member and a light transmitting region. 3. The light-transmitting sound absorber according to claim 1, wherein a plurality of said sound-absorbing materials are alternately arranged in a strip shape in a longitudinal direction on a surface of said light-transmitting panel member and a light-transmitting region. 4. The light-transmitting sound absorber according to claim 1, wherein the sound-absorbing material is arranged in a wave shape on the surface of the light-transmitting panel member. 5. The sound absorbing material according to claim 1, comprising a plate-shaped fiber molded body having a plurality of large-diameter through holes and a sheet-like transparent protective material having a plurality of small-diameter through holes covering the surface thereof. Translucent sound absorber. 6. The light-transmitting sound absorber according to claim 1, wherein the sound absorbing material comprises a plurality of donut-shaped fiber molded bodies and a sheet-shaped transparent protective material having a plurality of small-diameter through holes covering the surface thereof. 7. The translucent sound absorber according to claim 1, wherein the translucent panel member is made of polycarbonate or acrylic resin. 8. The light-transmitting sound absorber according to claim 5, wherein the fiber molded body is made of a polyester-based organic fiber. 9. The light-transmitting sound absorber according to claim 1, wherein the light-transmitting region of the light-transmitting panel member forms a concave lens.