JPH089853B2 - Sound absorbing cylinder and sound absorbing device using the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sound absorbing cylinder having excellent durability and sound absorbing characteristics, and a sound absorbing device using the same.

(Prior Art) Conventionally, the support structure made of concrete or steel is usually exposed on the back surface of the elevated road or the inner surface of the tunnel, and no special sound absorbing measures are taken in many cases. Therefore, the noise from the vehicle traveling on the road below the elevated road is reflected on the back surface of the elevated road, and the noise level in the surroundings is increased by several dB (A).

In order to eliminate such drawbacks, there is an example in which a sound absorbing panel containing glass wool in a perforated plate was experimentally attached to the backside of an elevated road, but the performance was stable due to deterioration due to water wetting and wind. In addition to that, the flat plate shape has poor cosmetic properties, and the flat plate shape cannot increase the sound absorption coefficient.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems, can exhibit stable sound absorbing performance with little deterioration due to wind and rain, is excellent in cosmetic properties, and has a high sound absorbing coefficient. The present invention has been completed to provide a sound-absorbing cylinder that is easy to install and a sound-absorbing device using the same for the back surface of an elevated road and the inner surface of a tunnel.

(Means for Solving the Problems) The first invention made to solve the above problems is as follows.
A sound absorbing plate that is compression molded by sandwiching both sides of a metal fiber mat with a perforated plate or a mesh is molded into a cylindrical shape with a diameter of 50 to 500 mm, and is closely adhered to the inner surface of the upper part to support both as a mounting member and a reinforcing member. The gist of the present invention is to provide a sound absorbing cylinder characterized in that an intermediate column is axially penetrated and fixed.

A second invention is a gist of a sound absorbing device, characterized in that the sound absorbing cylinder according to the first invention is attached to a rear surface of an elevated road or an inner surface of a tunnel at intervals of 0.5 to 2 times the diameter. is there.

Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

(Example) FIG. 1 shows an example of the sound absorbing cylinder (1) of the present invention, and (2) shows a metal produced by compressing and molding both sides of a metal fiber mat with porous plates or meshes. It is a sound absorbing board made of. As the metal fiber mat, a metal fiber mat having a diameter of 25 to 100 .mu. And having excellent corrosion resistance such as aluminum or stainless steel is pressure-bonded. As a member for sandwiching the outside in a sandwich shape, a perforated plate or mesh such as punching metal or expanded metal of aluminum or stainless steel is used. The aperture ratio of the perforated plate or mesh is 30 to 90%, preferably 60 to 85% from the viewpoint of strength and sound absorption. In the example, the opening is 2 mm,
Expanded metal with a wire diameter of 0.5 mm, a thickness of 0.5 mm and an aperture ratio of 80% is used. The metal fiber mat is sandwiched between such porous plates or meshes and compression-molded to form a sound absorbing plate (2) having a thickness of 1 to 5 mm.

In the present invention, such a sound absorbing plate (2) has a diameter of
The sound absorbing cylinder (1) is formed by molding it into a cylindrical shape of 50 to 500 mm. This diameter is determined by the installation workability and sound absorption characteristics.If the diameter is less than 50 mm, it will be necessary to install an extremely large number of wires to cover the back surface of the elevated road and the inner surface of the tunnel, and the sound absorption rate will be low. On the contrary, if it exceeds 500 mm, it becomes difficult to mount it at a high place. The most preferable diameter of the sound absorbing cylinder (1) is about 100 to 250 mm, and its length is 500 to 4 mm.
000 mm, more preferably about 1000 to 2000 mm.

Reference numeral (3) is a supporting middle pillar fixed by closely contacting the inner surface of the upper portion of the sound absorbing cylinder (1). The supporting pillar (3) has a function as a mounting member for attaching the sound absorbing cylinder (1) to the back surface of the elevated road or the inner surface of the tunnel, and the sound absorbing cylinder (1) body sufficiently supports the weight of a person. It also has a function as a reinforcing member that gives sufficient bending strength. For this reason, it is preferable that the supporting middle pillar (3) has a three-dimensional cross-sectional shape rather than a flat plate, and in the embodiment, a mold material having a substantially square cross-sectional shape is used. The contact portion between the supporting pillar (3) and the sound absorbing plate (2) is the sound absorbing cylinder (1).
It is preferable to have an R shape corresponding to the cylindrical surface.
Then, for example, a nut or the like is welded inside the vicinity of both ends of the supporting pillar (3) so that it can be attached to the back surface of the elevated road or the inner surface of the tunnel. In addition, (4) is a flat plate that covers the end surface of the sound absorbing cylinder (1).

Since the sound absorbing cylinder (1) of the present invention thus configured is made of a material having excellent durability as a whole, it has a sound absorbing performance even when exposed to wind and rain unlike the conventional soundproof panel using glass wool. Almost no deterioration, and because it is formed into a cylindrical shape, it exhibits excellent absorption characteristics for sound waves from any direction. Further, in the present invention, since the supporting middle pillar (3), which also serves as a mounting member and a reinforcing member, is axially penetrated so as to be in close contact with the inner surface of the upper portion thereof, it is easy to mount on the inner surface of an elevated road or tunnel. There is an advantage that a worker can walk on it when working.

2 to 4 show an embodiment of a sound absorbing device on the back surface of an elevated road using the sound absorbing cylinder (1).

As shown in these drawings, horizontal beams (7) extending in the width direction of the road via short pillars (6) on the lower surface of the bridge girder (5) under the elevated road (9) are arranged at regular intervals in the traveling direction. The sound absorbing cylinders (1) are suspended and attached to the lower surfaces of these horizontal beams (7) by bolts (8) at regular intervals. In the present invention, the sound absorbing cylinders (1) are not mounted densely, but are mounted at intervals of 0.5 to 2 times the diameter of the sound absorbing cylinders (1) in the width direction of the road as shown in FIG. . As described above, in the present invention, since the sound absorbing cylinders (1) are attached at intervals, a part of the sound waves generated from the vehicle traveling on the road below is directly absorbed by the sound absorbing cylinders (1), but the remaining sound waves are generated. It enters into the upper side of the sound absorbing tube (1) (the space between the sound absorbing tube (1) and the elevated road (9)) from the mutual gap, and the elevated road (9)
It is reflected by the lower surface of and is absorbed by the sound absorbing cylinder (1). As a result, according to the present invention, the sound absorption coefficient is improved rather than the case where the sound absorbing cylinders (1) are densely arranged, and the appearance when the elevated road (9) is looked up from the lower surface is good. ) Can be reduced. To this end, the sound absorbing cylinder (1) is provided by the pillar (6) as in the embodiment.
It is necessary to form a space between the space and the lower surface of the elevated road (9), and the height of this space is about 2 m in the embodiment. In addition, the installation interval of the sound absorbing cylinder (1) is 0.
If it is less than 5 times, the sound absorption coefficient decreases, and if it exceeds 2 times, the direct reflection of sound waves from the back surface of the elevated road (9) increases and the sound absorption coefficient also decreases, which is not preferable.

(Effects of the Invention) As described above, the sound absorbing cylinder of the first invention hardly deteriorates in sound absorbing performance even when exposed to wind and rain, and also serves as a mounting member and a reinforcing member by closely adhering to the upper inner surface thereof. The provision of the supporting pillars makes it easy to attach to the inside of an elevated road or tunnel and allows workers to walk on it during inspection work.

Further, the sound absorbing device of the second invention utilizing the above sound absorbing cylinder has a sound absorbing rate superior to that of the conventional flat plate type sound absorbing panel as shown in FIG. It is possible to prevent an increase in ambient noise level due to noise from a traveling vehicle being reflected on the backside of an elevated road or in a tunnel. In addition, the sound absorbing device of the present invention has good workability and inspection workability, has a good appearance, and it is possible to further enhance the cosmetic properties by painting, for example.

Therefore, the present invention has an extremely large contribution to industrial development as a sound absorbing cylinder and a sound absorbing device using the same, which eliminates the conventional problems.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of a sound absorbing tube of the present invention, FIG. 2 is a front view showing the entire sound absorbing device on the back surface of an elevated road of the present invention, and FIG. A front view and FIG. 4 are enlarged side views of the same part, and FIG. 5 is a graph of the sound absorption coefficient of the reverberation chamber method of the sound absorbing cylinder of the present invention and the conventional flat sound absorbing panel. (1): sound absorbing cylinder, (2): sound absorbing plate, (3): supporting pillar, (9): elevated road

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor, Shosuke Koga, 14 green house, 14 residential buildings, 100 Midorigaoka, Midori-cho, Owariasahi-shi, Aichi 207 (72) Inventor, Kaichi Kato, 2-chome, 22-chome, Kita-ku, Aichi (72) Inventor, Yoshihiro Ota 49 49, Nanaumi, Narumi-cho, Midori-ku, Nagoya, Aichi Prefecture

Claims (2)

[Claims] 1. A sound absorbing plate (2) which is compression molded by sandwiching both sides of a metal fiber mat with perforated plates or mesh and has a diameter of 50 to 50.
A sound absorbing cylinder characterized in that it is formed into a cylindrical shape of 0 mm, and is closely adhered to the inner surface of the upper part thereof, and a supporting middle pillar (3) which also serves as a mounting member and a reinforcing member is axially penetrated and fixed. 2. The sound-absorbing cylinder (1) according to claim 1 on the rear surface of the elevated road (9) or the inner surface of the tunnel, having a diameter of 0.5-2.
A sound absorbing device characterized by being installed at double intervals.