JP2012082631A - Soundproof panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a soundproof panel that provides higher soundproof effects than before.SOLUTION: A soundproof panel 1 includes an acoustic absorption body 2 placed to face a sound source side Sa, a sound insulation plate 4 placed to face a non-sound source side Sb, and a perforated plate 3 with a plurality of through holes 6. The perforated plate 3 is interposed between the acoustic absorption body 2 and the sound insulation plate 4. The sound insulation plate 4 is provided so as to shield a surface of the perforated plate 3 at the non-sound source side Sb.

Description

  The present invention relates to a soundproof panel installed to reduce various noises.

  Soundproof panels are installed in various places where noise reduction is required. Specific examples of installation locations include roads and tracksides, factory sites, and construction sites. Soundproof panels are also installed in buildings for the purpose of preventing sound leakage from indoors to outdoors.

  As soundproof panels suitable for such applications, for example, those described in Patent Documents 1 and 2 are known. The soundproof panel (porous soundproof structure) described in Patent Document 1 has an exterior plate and an interior plate arranged in an opposed state with an air layer interposed therebetween, and a large number of through holes are formed in the interior plate facing the sound source side. It has a structure. In addition, the soundproof panel described in Patent Document 2 has a structure in which a pair of perforated plates are arranged to face each other and a sound absorbing material such as glass wool is filled between the perforated plates.

JP 2006-85184 A JP 2007-162250 A

  However, none of the soundproofing panels described in Patent Documents 1 and 2 can provide a sufficient soundproofing effect, and it cannot be said that the soundproofing effect is particularly sufficient for low-frequency sound that is a problem with noise.

  A main object of the present invention is to provide a soundproof panel that has a higher soundproofing effect than conventional ones.

The first aspect of the present invention is:
A sound absorber disposed facing the sound source side;
A sound insulation board arranged facing the non-sound source side;
A perforated plate having a plurality of through holes,
The perforated plate is provided between the sound absorber and the sound insulating plate,
The sound insulation panel is a soundproof panel arranged in a state of shielding the non-sound source side surface of the perforated plate.

The second aspect of the present invention is:
The sound absorbing body is a soundproof panel according to the first aspect, characterized in that the sound absorbing body is made of a rigid porous sound absorbing material.

The third aspect of the present invention is:
The sound absorbing body is constituted by using a fiber-based sound absorbing material. The soundproof panel according to the first aspect, characterized in that

The fourth aspect of the present invention is:
The perforated plate is a soundproof panel according to the first, second, or third aspect, wherein the perforated plate is made of a calcium oxalate plate, a rock wool plate, or a flexible board.

  ADVANTAGE OF THE INVENTION According to this invention, the soundproof panel which has a higher soundproofing effect than before can be provided.

The structural example of the soundproof panel which concerns on the 1st Embodiment of this invention is shown, (A) is a front view in the figure, (B) is a side view. It is sectional drawing to which the part enclosed with the circle of FIG. 1 (B) was expanded. It is a figure which shows the example of the form of the through-hole in a perforated board. The structural example of the soundproof panel which concerns on the 2nd Embodiment of this invention is shown, (A) is a front view, (B) is a side view, (C) is a sectional side view in the figure. It is sectional drawing to which the part enclosed with the circle of FIG.4 (C) was expanded.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the embodiment of the present invention, description will be given in the following order.
1: First embodiment 1.1: Overall structure of soundproof panel 1.2: Partial structure of soundproof panel 1.3: Manufacturing method of soundproof panel 1.4: Effect 2: Second embodiment 1: Overall structure of soundproof panel 2.2: Partial structure of soundproof panel 2.3: Manufacturing method of soundproof panel 2.4: Effect

<1. First Embodiment>
FIG. 1 shows a configuration example of a soundproof panel according to a first embodiment of the present invention, in which (A) is a front view and (B) is a side view. FIG. 2 is an enlarged cross-sectional view of a circled portion of FIG.

(1.1: Overall structure of soundproof panel)
The soundproof panel 1 is for preventing sound incident from the sound source side Sa from leaking to the non-sound source side Sb. As described above, the soundproof panel 1 is installed in various places where noise reduction is required. At that time, the soundproof panel 1 is arranged with one main surface facing the sound source side Sa and the other main surface facing the non-sound source side Sb. The “sound source side” refers to the side on which the sound that causes noise is generated.

  The soundproof panel 1 includes a sound absorber 2, a perforated plate 3, and a sound insulating plate 4 as main components, and is a composite panel having a structure in which these are combined. The soundproof panel 1 has a configuration in which the structural members of the sound absorber 2, the perforated plate 3, and the sound insulating plate 4 are integrated, and the integrated structure is reinforced by the reinforcing frame 5. The soundproof panel 1 has a substantially rectangular parallelepiped structure as a whole panel. Exemplifying the external dimensions of the soundproof panel 1, the soundproof panel 1 has a longitudinal dimension of 1960 mm, a short dimension of 497 mm, and a thickness of 46 mm.

(1.2: Partial structure of soundproof panel)
(Sound absorber)
The sound absorber 2 absorbs sound incident on the sound absorber 2. The sound absorber 2 is a porous structure that absorbs sound over its entire surface. The sound absorber 2 is formed in a quadrangle in a front view (a rectangular shape or a square shape is also acceptable). The sound absorber 2 is arranged facing the sound source side Sa. In the following description, of the front and back surfaces of the sound absorber 2, the side facing the sound source side Sa is referred to as the front surface, and the opposite side is referred to as the back surface. The sound absorbing body 2 is a plate-like member having an appropriate thickness (for example, 30 mm to 50 mm), and is constituted by an integral structure of a rigid porous sound absorbing material. The “integrated structure” described here refers to a structure in which the main raw materials constituting the sound absorber 2 are the same and integrated. As a rigid porous sound-absorbing material that can be suitably applied as the sound-absorbing body 2, pore cells (registered trademark of the applicant) can be cited.

  The pore cell is a cement-type sound absorbing material. More specifically, the pore cell is a rigid porous sound-absorbing material based on calcium oxalate-based hydrate, in which small pores having a diameter of about 0.1 mm to 1 mm account for 85% or more of the total volume. It is. The pore cell is a rigid porous sound-absorbing material that absorbs sound by absorbing sound energy using the air permeability obtained by communicating the pores with each other. The sound absorber 2 made of this rigid porous sound absorber has weather resistance as well as sound absorption.

  A plurality of sound absorbers 2 are provided for one soundproof panel 1. In other words, the soundproof panel 1 is configured using a plurality of sound absorbers 2. These sound absorbers 2 are arranged in a horizontal row (or a vertical row is acceptable) so as to be adjacent to each other without a gap. Specifically, four sound absorbers 2 are arranged in a horizontal row. However, the present invention is not limited thereto, and the number of sound absorbers 2 used for one soundproof panel 1 can be arbitrarily changed. Further, one soundproof panel 1 may be configured by using one large sound absorber 2.

(Perforated plate)
The perforated plate 3 is provided mainly for improving the sound absorption performance of the soundproof panel 1. The perforated plate 3 is a so-called “perforated plate” and has a sound absorbing characteristic corresponding to its own open area ratio (hole diameter, hole pitch). The perforated plate 3 is formed in a square shape in front view, like the sound absorber 2 described above. The perforated plate 3 is disposed on the back side of the sound absorber 2. For this reason, even when the soundproof panel 1 is viewed from the sound source side Sa, the perforated plate 3 is hidden behind the sound absorber 2 and cannot be seen. The perforated plate 3 is a plate-like member having a plurality of through holes 6. For example, as shown in FIG. 3, the plurality of through holes 6 are provided uniformly in the entire perforated plate 3 in a lattice-like arrangement. Specifically, each through hole 6 is formed in a circular shape having a hole diameter (diameter) D = 6 mm, for example. The plurality of through-holes 6 are arranged at the same hole pitch P = 25 mm in both the vertical and horizontal directions.

  The perforated plate 3 is configured by using, for example, a calcium oxalate plate mixed with fibers. The thickness of the perforated plate 3 is set to be smaller than the thickness of the sound absorber 2. For example, if the thickness of the sound absorber 2 is set to 30 mm, the thickness of the perforated plate 3 is set to 12 mm corresponding to half or less of the thickness of the sound absorber 2.

(Sound insulation board)
The sound insulation plate 4 is provided mainly for enhancing the sound insulation performance of the sound insulation panel 1. However, the reason for providing the sound insulating plate 4 is not limited to that, and the sound insulating plate 4 functions as a protective material for protecting the perforated plate 3 disposed inside the sound insulating panel 1. The sound insulating plate 4 is formed in a square shape in front view, similar to the sound absorber 2 described above. The sound insulating plate 4 is disposed facing the non-sound source side Sb. The sound insulation plate 4 is arranged in a state of shielding the non-sound source side Sb surface of the perforated plate 3. For this reason, all of the plurality of through holes 6 formed in the perforated plate 3 are closed by the sound insulating plate 4. The sound insulating plate 4 is disposed so that the perforated plate 3 is sandwiched between the sound absorbing body 2 and the sound absorbing body 2 described above.

  The sound insulating plate 4 is a plate-like member that is thinner than the perforated plate 3. For example, if the thickness of the perforated plate 3 is set to 12 mm as described above, the thickness of the sound insulating plate 4 is set to 0.8 mm corresponding to 1/10 or less. The sound insulating plate 4 is configured using, for example, a metal plate having no holes, more preferably a steel plate having high corrosion resistance. The lower end portion of the sound insulating plate 4 is bent in an L shape, and the end surfaces of the sound absorber 2 and the perforated plate 3 are in contact with the bent portion. Although not shown, the upper end portion of the sound insulating plate 4 is also bent in an L shape, and the end surfaces of the sound absorber 2 and the perforated plate 3 are in contact with the bent portion.

(Reinforcement frame)
The reinforcing frame 5 reinforces the soundproof panel 1. The reinforcing frame 5 holds the sound absorbing body 2, the perforated plate 3, and the sound insulating plate 4 so as to be integrated. The reinforcing frame 5 is a long member having a substantially U-shaped cross section. Two reinforcing frames 5 are used for one soundproof panel 1. One reinforcing frame 5 is attached to the upper edge of the soundproof panel 1 and constitutes the upper frame of the soundproof panel 1. The other reinforcing frame 5 is attached to the lower edge portion of the soundproof panel 1 to form the lower frame of the soundproof panel 1. The reinforcing frame 5 is bent into a substantially U shape with a bending angle of approximately 90 °. The reinforcing frame 5 is obtained, for example, by bending a metal plate (preferably a steel plate having high corrosion resistance) thicker than the above-described sound insulating plate 4. The thickness of the reinforcing frame 5 is set to be larger than the thickness of the sound insulating plate 4 described above. For example, if the thickness of the sound insulating plate 4 is set to 0.8 mm, the thickness of the reinforcing frame 5 is set to 1.6 mm, which is twice that thickness.

(1.3: Manufacturing method of soundproof panel)
Next, the manufacturing method (assembly method) of the soundproof panel 1 will be described. The soundproof panel 1 is generally manufactured through three steps. Hereinafter, each step will be described.

(Process 1)
First, the plural (or singular) sound absorbers 2 and the perforated plate 3 are joined using an adhesive. In this case, both the sound absorber 2 and the perforated plate 3 are made of a cement-based material. For this reason, they are integrated by bonding the sound absorber 2 and the perforated plate 3 using an adhesive suitable for bonding cement materials.

(Process 2)
Next, the perforated plate 3 and the sound insulating plate 4 are joined using an adhesive. In this case, the perforated plate 3 is made of a cement-based material, and the sound insulating plate 4 is made of a metal-based material. For this reason, they are integrated by bonding the perforated plate 3 and the sound insulating plate 4 using an adhesive suitable for bonding a cement-based material and a metal-based material.
Through the above steps 1 and 2, a panel structure in which the sound absorber 2, the perforated plate 3 and the sound insulating plate 4 are integrated is obtained.

(Process 3)
Next, the reinforcing frame 5 that has been processed into a predetermined shape (substantially U-shaped) in advance is attached to the panel structure assembled in the above-described step 1 and step 2. One reinforcing frame 5 is attached to each of the upper edge portion and the lower edge portion of the panel structure. The reinforcement frame 5 is attached by fitting the reinforcement frame 5 into the panel structure with a gripping force obtained by the elasticity of the reinforcement frame 5 itself. However, if necessary, the panel structure and the reinforcing frame 5 may be fixed with an adhesive.
The assembly of the soundproof panel 1 is completed by the above steps 1, 2, and 3.

  In addition, you may perform said process 1 and process 2 by changing order. Moreover, it is desirable that the adhesive used in step 1 and the adhesive used in step 2 are both elastic adhesives having rubber-like elasticity. The reason is that when the soundproof panel 1 is actually installed, an effect of relieving the stress generated at each joint interface can be obtained.

(1.4: Effect)
According to the soundproof panel according to the first embodiment of the present invention, the following effects can be obtained.

  Since the perforated plate 3 is disposed in close contact with the back side of the sound absorber 2 due to the configuration of the soundproof panel 1, a high sound absorption rate can be realized by a synergistic effect of the respective sound absorbing performances. In addition, for sound incident on the soundproof panel 1, the sound is absorbed by the sound absorber 2 facing the sound source side Sa, and the sound transmitted through the sound absorber 2 is absorbed by the perforated plate 3. For this reason, the sound incident on the soundproof panel 1 can be efficiently attenuated while suppressing the reflection of sound on the surface of the soundproof panel 1. In particular, by incorporating the perforated plate 3 having a large number of through holes 6 inside the panel (the back side of the sound absorber 2), the attenuation effect of low frequency sound can be enhanced. Furthermore, when the sound absorber 2 is configured by the pore cell described above, there are innumerable fine holes on the entire surface and inside of the sound absorber 2, and these holes contribute to sound absorption. The synergistic effect provides a high sound absorption effect.

  Further, since the sound insulation plate 4 is disposed on the non-sound source side Sb of the sound insulation panel 1 and each through hole 6 of the perforated plate 3 is closed by this sound insulation plate 4, it can be absorbed by the sound absorber 2 and the perforated plate 3. The sound that did not exist can be blocked by the sound insulating plate 4. In addition, most of the sound incident on the soundproof panel 1 is absorbed by the sound absorber 2 and the perforated plate 3 before reaching the sound insulating plate 4. For this reason, even if the sound insulating plate 4 is composed of a thin metal plate or the like, a sufficient soundproofing effect can be obtained. Furthermore, since the perforated plate 3 incorporated in the panel is shielded by the sound insulating plate 4, it is possible to prevent the perforated plate 3 from being deteriorated due to intrusion of moisture from the outside of the panel.

  In addition, by joining the perforated plate 3 to the sound insulation plate 4 with an adhesive and integrating both, not only the sound insulation volume is increased by the presence of the sound insulation plate 4, but also the decrease in the transmission loss value due to the coincidence effect is suppressed. can do. Further, by joining and integrating the sound absorbing body 2, the perforated plate 3 and the sound insulating plate 4 with an adhesive, it is possible to increase the transmission loss value in the entire frequency range. Incidentally, the coincidence effect refers to a resonance phenomenon that is caused when the bending vibration of a material coincides with the vibration of an incident sound wave when a sound wave of a certain frequency is incident on a rigid material.

(Performance confirmation experiment)
Here, in order to confirm the performance of the soundproof panel 1, the following experiment was performed. As a result, experimental data demonstrating the effectiveness of the soundproof panel 1 was obtained.
In the experiment, two samples A and B were prepared for comparison. Sample A is a structure of a single sound absorber (pore cell absorber) 2 having a thickness of 30 mm, and sample B has a hole diameter of 6 mm and a hole pitch of 25 mm on the back side of the sound absorber (pore cell absorber) 2 having a thickness of 30 mm. This is a structure in which the perforated plate 3 is arranged.
The sound absorption coefficient of each sample A and B was measured by the normal incidence method.

As a result, for sample A, the sound absorption coefficient at a frequency of 100 Hz is 0.087, the sound absorption coefficient at a frequency of 125 Hz is 0.097, the sound absorption coefficient at a frequency of 400 Hz is 0.375, and the sound absorption coefficient at a frequency of 1000 Hz is 0.00. 499.
On the other hand, for sample B, the sound absorption coefficient at a frequency of 100 Hz is 0.127, the sound absorption coefficient at a frequency of 125 Hz is 0.124, the sound absorption coefficient at a frequency of 400 Hz is 0.377, and the sound absorption coefficient at a frequency of 1000 Hz is. 0.531.

  In this experimental result, although the effect of the combination of the perforated plate 3 is not so much recognized for the high frequency sound, the combination of the perforated plate 3 is remarkable especially for the low frequency sound regarded as important in noise. The effect was recognized.

  Further, as a modification of the soundproof panel 1 according to the first embodiment, the same experiment was performed using a “rock wool plate” instead of the “calcium oxalate plate” used for the perforated plate 3. However, the following results were obtained. That is, when a “rock wool plate” is used as the perforated plate 3, the sound absorption coefficient at a frequency of 100 Hz is 0.137, the sound absorption coefficient at a frequency of 125 Hz is 0.158, and the sound absorption coefficient at a frequency of 400 Hz is 0.411. The sound absorption coefficient at a frequency of 1000 Hz was 0.524.

  In this experimental result, compared with the case where the “calcium oxalate plate” is used as the perforated plate 3, the use of the “rock wool plate” realizes a higher sound absorption rate, and in particular, the sound absorption of low frequency sound. The rate was confirmed to be high. Incidentally, the “rockwool plate” described here refers to a rockwool sound absorbing plate in which a large number of fine holes exist irregularly on the surface, and sound absorbing performance is imparted by the presence of these holes. When the rock wool plate is applied, the surface of the rock wool plate may be a uniformly flat surface, or an uneven surface in which a plurality of grooves are formed in a lattice shape or a corrugated shape.

<2: Second embodiment>
FIG. 4 shows an example of the structure of a soundproof panel according to the second embodiment of the present invention, in which (A) is a front view, (B) is a side view, and (C) is a side sectional view. FIG. 5 is an enlarged cross-sectional view of a circled portion in FIG.

(2.1: Overall structure of soundproof panel)
The soundproof panel 21 is for preventing sound incident from the sound source side Sa from leaking to the non-sound source side Sb. As described above, the soundproof panel 21 is installed in various places where noise reduction is required. At that time, the soundproof panel 21 is arranged with one main surface facing the sound source side Sa and the other main surface facing the non-sound source side Sb.

  The soundproof panel 21 includes a sound absorber 22, a perforated plate 23, and a sound insulating plate 24 as main components, and is a composite panel having a structure in which these are combined. The soundproof panel 21 is configured by integrating the structural members of the sound absorber 22, the perforated plate 23 and the sound insulating plate 24. The soundproof panel 21 has a substantially rectangular parallelepiped structure as a whole panel. For example, the external dimensions of the soundproof panel 21 are 1960 mm, the short dimension is 497 mm, and the thickness is 60.2 mm.

(2.2: Partial structure of soundproof panel)
(Sound absorber)
The sound absorber 22 absorbs sound incident on the sound absorber 22. The sound absorber 22 is formed in a quadrangle in a front view (can be a rectangle or a square). The sound absorber 22 is arranged facing the sound source side Sa. Further, as shown in FIG. 5, the sound absorber 22 is configured by using a surface plate 22 a and a fiber-based sound absorbing material (hereinafter referred to as “sound absorbing material”) 22 b.

  The surface plate 22a has both a function as a surface protective material for protecting the surface of the soundproof panel 21 and a function for holding the sound absorbing material 22b. The surface plate 22a is disposed on the surface of the soundproof panel 21 so as to face the sound source side Sa. The surface plate 22a is configured using, for example, a so-called punching metal in which a plurality of through holes are provided in a relatively thin metal plate. Each through hole of the surface plate 22a is for taking the sound incident on the soundproof panel 21 from the sound source side Sa into the panel while partially absorbing the sound. The dimensions of the through holes applied to the surface plate 22a are set to, for example, a hole diameter = 8 mm and a hole pitch = 20 mm. The surface plate 22a is formed in a horizontally long rectangle. A plurality (four in the illustrated example) of button washers 25 are attached to the surface plate 22a. Each button washer 25 is for holding the surface plate 22a in an appropriate mounting position.

  The sound absorbing material 22b absorbs sound that could not be absorbed by the surface plate 22a. The sound absorbing material 22b is configured using, for example, a fiber material such as glass wool. Specifically, for example, in consideration of weather resistance and water resistance, it is preferable to use a combination of glass wool 32k and a water repellent glass cloth for the sound absorbing material 22b. The sound absorbing material 22b is filled inside the soundproof panel 21 and between the surface plate 22a described above and a perforated plate 23 described later. Further, the sound absorbing material 22b is filled over the entire panel when the soundproof panel 21 is viewed from the back side of the surface plate 22a.

(Perforated plate)
The perforated plate 23 is provided mainly for improving the sound absorption performance of the soundproof panel 21. The perforated plate 23 is a so-called “perforated plate” and has a sound absorbing characteristic corresponding to its own open area ratio (hole diameter, hole pitch). The perforated plate 23 is formed in a square shape in front view, like the sound absorber 22 described above. The perforated plate 23 is disposed on the back side of the sound absorber 22. For this reason, even when the soundproof panel 21 is viewed from the sound source side Sa, the perforated plate 23 is shielded by the sound absorber 22 and cannot be seen. The perforated plate 23 is a plate-like member having a plurality of through holes 26. The plurality of through holes 26 are uniformly provided in the entire perforated plate 23 in a lattice-like arrangement, for example, like the through holes 6 shown in FIG. Specifically, each through hole 26 is formed in a circular shape having a hole diameter (diameter) = 8 mm, for example. The plurality of through holes 26 are arranged with the same hole pitch = 25 mm in both the vertical and horizontal directions.

  The perforated plate 23 is configured using, for example, a flexible board. The thickness of the perforated plate 23 is set to a dimension smaller than the thickness of the sound absorber 22. For example, if the thickness of the sound absorber 22 is set to 50 mm, the thickness of the perforated plate 23 is set to 6 mm, which is sufficiently thinner than that.

(Sound insulation board)
The sound insulation plate 24 is provided for the purpose of improving the sound insulation performance of the sound insulation panel 21 and for protecting the perforated plate 23 disposed inside the sound insulation panel 21 as in the first embodiment. The sound insulating plate 24 is formed in a square shape in front view, like the sound absorber 22 described above. The sound insulating plate 24 is arranged facing the non-sound source side Sb. The sound insulation plate 24 is arranged in a state of shielding the non-sound source side Sb surface of the perforated plate 23. For this reason, all of the plurality of through holes 26 formed in the perforated plate 23 are closed by the sound insulating plate 24. The sound insulating plate 24 is disposed so that the perforated plate 23 is sandwiched between the sound absorbing body 22 and the sound absorbing body 22 described above.

  The sound insulating plate 24 is a plate-like member that is thinner than the perforated plate 23. The details (thickness, material, etc.) of the sound insulating plate 24 are the same as those of the sound insulating plate 4 used in the first embodiment. The upper and lower ends and the left and right ends of the sound insulating plate 24 are bent in a substantially U shape so as to protrude toward the sound source side Sa, and these bent portions form the outer peripheral frames 24a, 24b, 24c, 24d of the soundproof panel 21. is doing. That is, the outer peripheral frame 24 a forms the upper frame of the soundproof panel 21, and the outer peripheral frame 24 b forms the lower frame of the soundproof panel 21. The outer peripheral frame 24 c forms one side frame of the soundproof panel 21, and the outer peripheral frame 24 d forms the other side frame of the soundproof panel 21. These outer peripheral frames 24a, 24b, 24c, and 24d are joined at the four corners C1, C2, C3, and C4 of the soundproof panel 21 at overlapping portions.

(2.3: Manufacturing method of soundproof panel)
Next, a manufacturing method (assembly method) of the soundproof panel 21 will be described. The soundproof panel 21 is generally manufactured through two processes. Hereinafter, each step will be described.

(Step 11)
First, the perforated plate 23 and the sound insulating plate 24 are joined using an adhesive. In this case, the perforated plate 23 is made of a cement-based material, and the sound insulating plate 24 is made of a metal-based material. For this reason, the perforated plate 23 and the sound insulating plate 24 are joined by using an adhesive (preferably an elastic adhesive) suitable for joining the cement-based material and the metal-based material, thereby integrating them. Turn into.

(Step 12)
Next, the sound absorbing material 22b is filled in the space surrounded by the outer peripheral frames 24a, 24b, 24c, and 24d of the sound insulating plate 24, and the surface plate 22a is attached using a plurality of button washers 25. At that time, the outer peripheral frames 24a, 24b, 24c, 24d are coupled to each other at the four corners C1, C2, C3, C4 of the soundproof panel 21, and the surface plate 22a is fixed to the outer peripheral frames 24a, 24b, 24c, 24d. To do.
The assembly of the soundproof panel 21 is completed by the above steps 11 and 12.

(2.4: Effect)
According to the soundproof panel according to the second embodiment of the present invention, the following effects can be obtained.

  Since the perforated plate 23 is disposed in close contact with the sound absorber 22 on the back surface side of the soundproof panel 21, a high sound absorption rate can be realized by a synergistic effect of the respective sound absorbing performances. Moreover, with respect to the sound incident on the soundproof panel 21, the sound is absorbed by the sound absorber 22 facing the sound source side Sa, and the sound transmitted through the sound absorber 22 is absorbed by the perforated plate 23. For this reason, the sound incident on the soundproof panel 21 can be efficiently attenuated while suppressing the reflection of sound on the surface of the soundproof panel 21. In particular, by incorporating a perforated plate 23 having a large number of through holes 26 inside the panel (the back side of the sound absorber 22), the attenuation effect of low frequency sound can be enhanced.

  In addition, since the sound insulation plate 24 is disposed on the non-sound source side Sb of the sound insulation panel 21 and each through hole 26 of the perforated plate 23 is closed by the sound insulation plate 24, the sound absorbing body 22 and the perforated plate 23 can absorb the sound insulation plate. The sound that does not exist can be blocked by the sound insulating plate 24. In addition, most of the sound incident on the sound insulation panel 21 is absorbed by the sound absorber 22 and the perforated plate 23 before reaching the sound insulation plate 24. For this reason, even if the sound insulating plate 24 is made of a thin metal plate or the like, a sufficient soundproofing effect can be obtained. Furthermore, since the perforated plate 23 incorporated in the panel is shielded by the sound insulating plate 24, the perforated plate 23 can be prevented from being deteriorated due to intrusion of moisture from the outside of the panel.

  Further, by joining the perforated plate 23 to the sound insulating plate 24 with an adhesive and integrating them, not only the sound insulation volume is increased due to the presence of the sound insulating plate 24, but also the decrease in the transmission loss value due to the coincidence effect is suppressed. In addition, it is possible to increase the transmission loss value in the entire frequency range.

  The technical scope of the present invention is not limited to the above-described embodiments, and various modifications and improvements may be added within the scope of deriving specific effects obtained by the constituent requirements of the invention and combinations thereof. Including.

For example, as the perforated plate 3 of the soundproof panel 1 according to the first embodiment, a “flexible board” may be used instead of the “calcium oxalate plate” or the “rock wool plate”.
Further, as the perforated plate 23 of the soundproof panel 21 according to the second embodiment, a “calcium oxalate plate” or a “rock wool plate” may be used instead of the “flexible board”.

DESCRIPTION OF SYMBOLS 1 ... Soundproof panel 2 ... Sound absorption body 3 ... Perforated board 4 ... Sound insulation board 5 ... Reinforcement frame 6 ... Through hole 21 ... Sound insulation panel 22 ... Sound absorption body 23 ... Perforated board 24 ... Sound insulation board 26 ... Through hole

Claims (4)

A sound absorber disposed facing the sound source side;
A sound insulation board arranged facing the non-sound source side;
A perforated plate having a plurality of through holes,
The perforated plate is provided between the sound absorber and the sound insulating plate,
The sound insulation panel, wherein the sound insulation plate is arranged in a state of shielding the non-sound source side surface of the perforated plate. The soundproof panel according to claim 1, wherein the sound absorber is made of a rigid porous sound absorber. The soundproof panel according to claim 1, wherein the sound absorber is configured using a fiber-based sound absorber. The soundproof panel according to claim 1, 2 or 3, wherein the perforated plate is made of a calcium oxalate plate, a rock wool plate, or a flexible board.

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