JP3301680B2 - Sound absorbing structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lower part of an elevated structure such as a railway, an elevated road, a bridge or an elevated road, or a side surface of a trench, a semi-underground road, a highway, or a ceiling surface of a wall or an underground passage of a general building. The present invention relates to a sound-absorbing structure attached to a device such as

[0002]

2. Description of the Related Art Conventionally, as this kind of sound absorbing structure, there has been known a sound absorbing structure comprising only a sound absorbing material and a space formed behind the sound absorbing material as shown in FIGS.

[0003]

However, in the conventional sound absorbing structure as described above, glass wool is used as a sound absorbing material in FIG. 7 and an aluminum fiber plate is used in FIG. 8, for example.
As a result of measuring the sound absorption performance by the normal incidence method, FIG. 9, FIG.
There is a drawback that the sound absorption performance in a low frequency region is inferior as 0.

Accordingly, the present invention solves the above-mentioned problems,
An object of the present invention is to provide a sound absorbing structure having an excellent sound absorbing effect.

[0005]

In order to achieve the above object, the present invention has the following arrangement. That is, the sound absorbing structure according to the present invention has a sound absorbing unit in which a plurality of sound absorbing units each including a porous sound absorbing material and a space formed behind the porous sound absorbing material are opened in parallel with each other to form a sound absorbing hole. And a resonance chamber is formed between the sound absorbing member and the sound insulating member provided behind the sound absorbing section, and the resonance chamber and the sound absorbing hole communicate with each other.

[0006]

According to the sound absorbing structure of the present invention, the sound absorbing effect of the sound absorbing unit comprising the porous sound absorbing material and the space formed behind the porous sound absorbing material and the sound insulating member provided behind the sound absorbing unit. Excellent sound absorbing performance is exhibited by a synergistic effect with the damping effect of the resonance chamber formed in the above. In other words, low-frequency sound is attenuated and absorbed in the resonance chamber, and medium-high-frequency sound is absorbed by the porous sound absorbing material and the space. The sound absorbing effect is exhibited.

[0007]

Next, an embodiment of the present invention will be specifically described with reference to the drawings. First, FIG. 1 is a cross-sectional view showing one embodiment of the sound absorbing structure of the present invention.
1 and a space 12 formed behind a porous sound absorbing material 11. More specifically, the sound absorbing unit 1 includes a front wall 13, a rear wall 14, left and right side walls 15, a top plate 16, and a bottom plate 17, and a large number of small holes 1 are formed in the front wall 13.
8, a porous sound absorbing material 11 made of glass wool is attached to the inside of the front wall 13, and a space 12 is formed behind the porous sound absorbing material 11.

Thus, a plurality of the sound absorbing units 1 are juxtaposed so that a sound absorbing hole 2 is formed between the adjacent sound absorbing units 1 and 1 to form a sound absorbing portion A. Behind the sound absorbing portion A, a resonance chamber B communicating with the sound absorbing hole 2 is partitioned by a sound insulating member 3 such as a metal plate. It said sound absorbing holes 2 are made with the as bending like Figure 1, angled, are made with curved shape.

The resonance chamber B is formed behind the sound absorbing part A. In FIG. 1, the resonance chamber B is formed integrally with the sound absorbing part A.

FIG. 2 shows an embodiment in which the front wall 13 and the porous sound absorbing material 1 are used.
1 is the same as that of the embodiment of FIG. As the porous sound absorbing material 11, a fiber body such as rock wool, a plastic foam such as polyurethane foam, or a foam such as aluminum or concrete may be used in addition to glass wool and aluminum fiber plate. When glass wool or rock wool is used for the porous sound absorbing material 11, the porous sound absorbing material 11 may be covered with a fluororesin film or the like in order to prevent deterioration of the adhesive.

FIG. 3 is a partially cutaway perspective view showing another embodiment of the present invention. In this embodiment, an aluminum fiber plate is used for the porous sound absorbing material 11 in common with the front wall 13. Also,
The sound absorbing hole 2 has a bent shape, a sound projecting edge on the resonance chamber B side, and a sound absorbing hole having no projecting edge. Also, the shape of the sound absorbing unit 1 is variously different.
Further, the shape of the resonance chamber B is also variously different, such as a portion where the plurality of sound absorbing holes 2 are communicated, and a portion where the one sound absorbing hole 2 is communicated. As described above, it is preferable to combine a plurality of resonance chambers B having different shapes and sizes because noises in various sound ranges can be absorbed.

FIG. 4 is a sectional view showing still another embodiment of the present invention. In the case of this embodiment, the sound absorbing portion A is provided on the back side of the elevated road, the back side of the elevated road is used as the sound insulating member 3, and a resonance chamber B is provided between the sound absorbing portion A and the back side of the elevated road. In the case of FIG. 4, a side wall 15 made of a decorative board is provided between the back end of the elevated road and the end of the sound absorbing section A, and the decorative chamber partitions the resonance chamber B. Also in this case, it is preferable to change the size and shape of the sound absorbing portion A and the resonance chamber B in various ways because the sound absorbing performance is improved.

[0013]

According to the sound absorbing structure according to the present invention, a plurality of sound absorbing units each including a porous sound absorbing material and a space formed behind the porous sound absorbing material are provided in parallel with a sound absorbing hole, thereby forming a sound absorbing portion. The sound-absorbing hole is bent and a resonance chamber is formed between the sound-absorbing part and the sound-insulating member provided behind the sound-absorbing part, so that it comprises a porous sound-absorbing material and a space formed behind the porous sound-absorbing material. The sound absorbing unit absorbs the mid-high frequency range sound, attenuates and absorbs the low frequency range sound in the resonance room, and exhibits a sound absorbing effect on a wide range of noise from low frequency range to mid-high frequency range sound as a whole. It is.

Further, the sound absorbing structure according to the present invention comprises a front wall, a rear wall, left and right side walls, a top plate and a bottom plate. A space is formed behind the sound absorbing material to form a sound absorbing unit, a plurality of sound absorbing units are opened in parallel with a sound absorbing hole to form a sound absorbing unit, a resonance chamber is formed behind the sound absorbing unit, and a resonance chamber is formed. When the sound absorbing hole and the sound absorbing hole communicate with each other, the sound absorbing hole and the sound absorbing hole are integrally formed, and can be easily constructed along a road or a railway, similarly to the conventional sound absorbing structure.

Further, when the resonance chamber of the sound absorbing structure includes a plurality of chambers having different sizes and shapes, noises in various sound ranges can be absorbed.

Further, when the sound insulating member of the sound absorbing structure is a wall surface of an existing structure, the sound insulating member can be omitted, and the sound absorbing structure is not bulky and is inexpensive, which is preferable.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example in which glass wool is used as a porous sound absorbing material of a sound absorbing structure of the present invention.

FIG. 2 is a sectional view showing an example in which an aluminum fiber plate is used as a porous sound absorbing material of the sound absorbing structure of the present invention.

FIG. 3 is a partially cutaway perspective view showing another embodiment of the sound absorbing structure of the present invention.

FIG. 4 is a sectional view showing still another embodiment of the sound absorbing structure of the present invention.

FIG. 5 is a graph showing the results of measuring the sound absorbing performance of a sound absorbing structure according to the present invention using glass wool as a porous sound absorbing material by the normal incidence method.

FIG. 6 is a graph showing the results of measuring the sound absorbing performance of a sound absorbing structure according to the present invention in which an aluminum fiber plate is used as the porous sound absorbing material by the normal incidence method.

FIG. 7 is a cross-sectional view of a conventional sound absorbing structure using glass wool as a porous sound absorbing material.

FIG. 8 is a cross-sectional view of a conventional sound absorbing structure using an aluminum fiber plate as a porous sound absorbing material.

FIG. 9 is a graph showing the results of measuring the sound absorbing performance of a conventional sound absorbing structure using glass wool as a porous sound absorbing material by the normal incidence method.

FIG. 10 is a graph showing the results of measuring the sound absorbing performance of a conventional sound absorbing structure using an aluminum fiber plate as a porous sound absorbing material by the normal incidence method.

[Explanation of symbols]

 Reference Signs List A sound absorbing part B resonance chamber 1 sound absorbing unit 11 porous sound absorbing material 12 space part 13 front wall 14 rear wall 15 side wall 16 top plate 17 bottom plate 18 small hole 2 sound absorbing hole 3 sound insulating member

Claims (5)

(57) [Claims] A sound absorbing unit comprising a porous sound absorbing material and a space formed behind the porous sound absorbing material, wherein a plurality of sound absorbing units are opened in parallel to form a sound absorbing unit, and the sound absorbing hole is formed in a bent shape; A sound-absorbing structure in which a resonance chamber is formed between the sound-absorbing member and a sound-insulating member provided behind the sound-absorbing portion, and the resonance chamber and the sound-absorbing hole communicate with each other. 2. The sound absorbing structure comprises a front wall, a rear wall, left and right side walls, a top plate, and a bottom plate. A large number of small holes are formed in the front wall, and a porous sound absorbing material is provided inside the small holes. Attached, a space portion is formed behind the sound absorbing material to form a sound absorbing unit, a plurality of sound absorbing units are opened side by side with a sound absorbing hole to form a sound absorbing portion, a resonance chamber is formed behind the sound absorbing portion, The resonance chamber and the sound absorbing hole are communicated with each other.
The sound-absorbing structure according to any one of the preceding claims. 3. The sound absorbing structure according to claim 1, wherein a plurality of resonance chambers are provided behind the sound absorbing portion. 4. The sound absorbing structure according to claim 3, wherein said resonance chamber comprises a plurality of resonance chambers having different sizes. 5. The sound absorbing structure according to claim 1, wherein the sound insulating member provided behind the sound absorbing portion is a wall surface of an existing structure.