JP2004076462A - Sound isolation panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sound isolation panel capable of obtaining a better sound insulation performance. <P>SOLUTION: The sound isolation panel has a large number of cells 2c independent from each other and is formed of partition walls 2b, at the same time, it includes a honeycomb core 2 forming communicating holes 2c with each other in the partition walls 2b and plates 3 and 3 having sound isolation efficiency respectively laminated on the front side and the back side of the honeycomb core 2, and a sound absorption performance of the honeycomb core 2 is increased in cooperation with the plates 3 on both sides thereof and the communicating holes 2c to improve the sound isolation performance of the sound isolation panel 1. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a soundproof panel used as a soundproof wall, a partition, a fitting, or the like for the purpose of soundproofing or the like.
[0002]
[Prior art]
As one of conventional sound insulation panels of this type, a flash panel in which a plate material is adhered to the front and back surfaces of a honeycomb core material is used. The sound absorption mechanism of the honeycomb core material uses the viscous resistance of air. When sound enters the cells that make up the honeycomb core material, the sound energy is attenuated by the viscosity of the air in the cells. Thereby, a sound absorbing effect is obtained. Sound insulation is performed by attenuating the sound transmitted from the front surface to the back surface of the flash panel by the sound absorption by the honeycomb core material and the reflection of the sound by the plate material. Further, since the flash panel uses the honeycomb core material, the flash panel is very lightweight and has excellent strength characteristics.
[0003]
[Problems to be solved by the invention]
However, the above-described flash panel has a simple configuration in which a plate material is simply attached to the front and back surfaces of the honeycomb core material. As described above, the sound-insulating mechanism uses sound reflection and honeycomb core material. The required sound insulation performance may not always be obtained because it is only a simple one such as attenuation due to the viscous resistance of the air inside.
[0004]
The present invention has been made to solve such a problem, and an object of the present invention is to provide a sound insulation panel that can obtain better sound insulation performance.
[0005]
[Means for Solving the Problems]
In order to achieve this object, the invention according to claim 1 of the present invention provides a honeycomb core material having a large number of independent cells formed by partition walls, and having a communication hole formed in the partition walls to communicate the cells. And a sheet material having sound insulation properties laminated on the front surface side and the back surface side of the honeycomb core material, respectively.
[0006]
According to this sound insulation panel, the sound generated on the front side first reaches the plate member on the front side. At that time, a part of the sound is reflected on the surface of the plate material, and the sound incident on the other plate material reaches the honeycomb core material after being attenuated in the plate material. The honeycomb core material has a large number of cells formed therein, independent of each other, and the sound is attenuated by viscous resistance of air when passing through each cell. In addition, since a communication hole that connects cells is formed in a partition wall that separates adjacent cells, a part of the sound incident into the cell passes through the communication hole and enters the adjacent cell. . When the sound enters the adjacent cell, the phase of the sound is reversed, that is, since the phase of the sound entering the cell from the surface plate is opposite to the sound from the plate, the communication hole is formed. The energy of the passing sound is attenuated by canceling each other, and the sound is absorbed in the honeycomb core material. Next, the sound reaches the plate material on the back surface side. At this time, the sound is attenuated inside the plate material, and then reaches the back surface side of the sound insulation panel, as in the case where the sound has passed through the plate material on the front surface side.
[0007]
As described above, the sound is attenuated in each layer, and as a result, the magnitude of the sound transmitted to the back surface side of the sound insulation panel can be effectively reduced. In particular, the sound absorption performance of the honeycomb core material can be improved by canceling the sound by the communication holes formed in the partition walls of the honeycomb core material, and therefore, it is possible to obtain excellent sound insulation performance as a whole sound insulation panel. it can.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 and 2 show a sound insulation panel 1 according to a first embodiment of the present invention. The sound insulation panel 1 includes a honeycomb core member 2 and plate members 3, 3 and the like laminated on the front side and the rear side, respectively.
[0009]
The honeycomb core material 2 is formed of a honeycomb structure in which a large number of cells 2a independent of each other are formed, the front surface and the back surface are open, and the whole is formed in a panel shape. As the honeycomb core material 2, a commercially available material can be used. Further, from the viewpoint of weight reduction, it is preferable that the material thereof has a small specific gravity, such as paper or a lightweight metal material. Further, there is no particular limitation on the shape and size of the cell 2a. For example, a general-purpose cell having a diameter of the cell 2a of 1/2 inch or 3/4 inch can be adopted. In the present embodiment, the honeycomb core material 2 is made of kraft paper, has a thickness of 15 mm, and has a cell 2a having a size of 1/2 inch.
[0010]
A large number of cells 2a are formed by partition walls 2b, and a communication hole 2c that connects adjacent cells 2a is formed at the center of the partition wall 2b in the thickness direction of the honeycomb core material 2. As shown in FIG. 3, in one step of manufacturing the sound insulating panel 1, the communication hole 2 c is formed in the honeycomb core material 2 when the honeycomb core material 2 is in a folded state before being expanded. For example, it is formed in advance at an interval of 12 mm, and its diameter is, for example, 3 mm.
[0011]
The nonwoven fabric 4 is directly attached to the front and back surfaces of the honeycomb core material 2 respectively. The nonwoven fabric 4 is made of, for example, polyester (103 g / m ² ), has a thickness of, for example, 0.3 mm, has air permeability, and covers the entire front and back surfaces of the honeycomb core material 2 respectively. ing. The plate members 3, 3 are attached to the nonwoven fabrics 4, 4 so as to cover the entire front and back surfaces of the nonwoven fabrics 4, 4, respectively. Each of the plate members 3 is made of, for example, a Lauan plywood having a sound insulation property, and has a thickness of, for example, 5.5 mm.
[0012]
According to the sound insulation panel 1 having the above configuration, the sound generated on the front side first reaches the plate member 3 on the front side. At that time, a part of the sound is reflected on the surface of the plate material 3, and the other sound that has entered the plate material 3 is attenuated in the plate material 3 and then reaches the nonwoven fabric 4 on the surface side. The sound is slightly attenuated even when passing through the nonwoven fabric 4, and then enters the honeycomb core material 2. The sound is attenuated by the viscous resistance of air when passing through each cell 2a in the honeycomb core material 2. In addition, part of the sound that has entered the cell 2a passes through the communication hole 2c formed in the partition wall 2b and enters the adjacent cell 2a. At this time, since the phase of the sound is reversed, that is, the phase of the sound entering the cell 2a from the surface plate 3 via the nonwoven fabric 4 is reversed, the sound from the plate 3 and the communication hole When the sound passing through 2c cancels out, the energy is attenuated and the sound is absorbed in the honeycomb core material 2. Next, the sound reaches the nonwoven fabric 4 on the back side, and is slightly attenuated when passing through the nonwoven fabric 4 on the front side, and reaches the plate material 3 on the back side. When passing through the plate material 3 on the back surface side, similarly to when passing through the plate material 3 on the front surface side, after being attenuated inside, it reaches the back surface side of the sound insulation panel 1.
[0013]
As described above, the sound is attenuated in each layer, and as a result, the volume of sound transmitted from the front side to the back side of the sound insulating panel 1 can be effectively reduced. In particular, the sound absorption performance of the honeycomb core material 2 can be improved by canceling out the sound by the communication holes 2c formed in the partition walls 2b of the honeycomb core material 2, and as a result, the overall sound insulation panel 1 is excellent. Sound insulation performance can be obtained.
[0014]
In addition, since the honeycomb core material 2 and the plate material 3 do not directly contact each other due to the interposition of the nonwoven fabric 4, the plate materials 3 on the front surface side and the back surface side are mutually vibrated via the honeycomb core material 2. Never be combined. For this reason, it is possible to prevent a sound bridge from being generated between the plate members 3 on the front surface side and the rear surface side, and to prevent the sound insulation performance of the sound insulation panel 1 from being adversely affected. Since the diameter of the communication hole 2c is 3 mm and the thickness of the honeycomb core material 2 is 15 mm, the size of the communication hole 2c is sufficiently smaller than the thickness of the honeycomb core material 2. Thereby, the sound insulation performance of the sound insulation panel 1 can be improved without substantially reducing the rigidity of the sound insulation panel 1.
[0015]
FIG. 4 shows a sound insulation panel 10 according to a second embodiment of the present invention. The present embodiment is different from the first embodiment only in the number of communication holes 2c formed in the partition walls 2b of the honeycomb core material 2. That is, in the first embodiment, only one communication hole 2c is formed at the center of the partition wall 2b, whereas in the present embodiment, the thickness of the sound insulation panel 10 in the first embodiment is reduced. Two communication holes 2c having the same size as the communication hole 2c are formed side by side. These two communication holes 2c, 2c are also formed in the present embodiment in a state where the honeycomb core material 2 is folded. According to the sound insulation panel 10, as in the case of the sound insulation panel 1 of the first embodiment, the sound absorbing performance of the honeycomb core material 2 is improved by the sound canceling action due to the formation of the two communication holes 2 c and 2 c. Thereby, the sound insulation performance of the sound insulation panel 10 can be improved.
[0016]
FIG. 5 shows an example of a test result performed to confirm the sound insulation performance of the sound insulation panels 1 and 10 of the first and second embodiments. In this test, the sound insulation panels 1 and 10 having the above-described configuration and the sound insulation panel as a comparative example in which the communication hole 2c was not formed in the honeycomb core material 2 were tested according to JIS A1419 on “air sound insulation performance of building members in a laboratory”. Measurement method ", taking into account the evaluation standards of the Architectural Institute of Japan. Specifically, as shown in FIG. 6, sound was generated in the sound source room in a state where the test pieces of the sound insulation panels 1 and 10 and the sound insulation panel of the comparative example were installed between the sound source room and the sound reception room. The sound pressure level at that time is measured in each of the sound source room and the sound receiving room, and a difference (hereinafter referred to as “sound pressure level difference”) ΔD between the two sound pressure levels is obtained. When the value of the obtained sound pressure level difference ΔD exceeds the reference curve in all the frequency bands, the sound insulation class is represented by the name of the reference curve. The dimensions of each specimen are 745 mm long × 1785 mm wide, and the thickness of each member such as the honeycomb core material 2 of the comparative example is the same as that of the above-described sound insulation panels 1 and 10.
[0017]
FIGS. 5A to 5C show test results for the sound insulation panels 1 and 10 and the comparative example, respectively. As shown in FIG. 3C, in the comparative example in which the communication hole 2c is not formed, the sound pressure level difference ΔD between the sound source room and the sound receiving room is an octave band center frequency (hereinafter simply referred to as “frequency”). As f increases, it gradually increases. Further, the value of the sound pressure level difference ΔD of this comparative example is low as a whole, and its sound insulation grade is D-20. The decrease in the sound pressure level difference ΔD when the frequency f is around 300 Hz and 3000 Hz is due to low-range resonance transmission around 300 Hz, and is due to the coincidence effect around 3000 Hz.
[0018]
On the other hand, the sound insulation panels 1 and 10 also show a tendency for the sound pressure level difference ΔD to gradually increase with an increase in the frequency f, similarly to the comparative example. Except at around 200 Hz and at or above about 5000 Hz, the values are higher than those of the comparative example, and the sound insulating panels 1 and 10 have higher overall sound insulating performance than the comparative example. In this case, the lowering range of the sound pressure level difference ΔD of the sound insulating panels 1 and 10 is shifted to a lower frequency range as compared with the comparative example, and the lowering range due to resonance transmission is shifted to a lower frequency range. As for the frequency range, it has shifted to a higher frequency range. As a result, the sound insulation panels 1 and 10 all have a sound insulation rating of D-25. The reason why the range of decrease in the sound pressure level difference ΔD changes as described above is as follows.
[0019]
In the sound insulation panels 1 and 10, since the communication holes 2c are formed in the honeycomb core material 2, air is not sealed in one cell 2a. Due to the pressure, the air in the cell 2a is pushed out from the communication hole 2c into the adjacent cell 2a. As a result, when the individual cells 2a are regarded as air springs, the air springs are softened, and the natural frequency of the cells 2a at which low-range resonance transmission occurs is reduced. As a result, the region where the sound pressure level difference is reduced shifts to a lower frequency region. On the other hand, since the communication hole 2c is formed, the rigidity of the sound insulation panel 1 is slightly reduced, and the coincidence frequency at which the coincidence effect occurs is increased. Accordingly, the decrease range of the sound pressure level difference is further increased. Move to higher frequency range.
[0020]
As a result, it was confirmed that the sound insulation panels 1 and 10 according to the first and second embodiments achieved a sound insulation grade one step higher than that of the comparative example, and that the sound insulation performance was improved.
[0021]
FIG. 7 shows an example of a test result performed to confirm the sound absorption performance of each of the sound insulation panels 1 and 10 and the comparative example. This test was carried out based on "Method for measuring reverberation chamber method sound absorption coefficient" according to JIS A1409. The test specimens used for this measurement were those obtained by removing the front and back plate members 3 from the above-mentioned one for measuring the sound insulation performance (hereinafter, referred to as “sound absorption test specimens A to C”, respectively), and their dimensions. Is 800 mm long × 1890 mm wide.
[0022]
FIGS. 7A to 7C show test results of the sound absorbing test pieces A to C, respectively. According to this, the reverberation chamber method sound absorption coefficient (hereinafter simply referred to as “sound absorption coefficient”) SC of the sound absorption test specimens A to C once drops and rises greatly when the frequency is around 125 Hz, and then the frequency f rises. As you do, it is getting higher gradually. Also, over almost all frequency bands, the sound absorption coefficient SC of the sound absorption test pieces A and B is slightly lower than the sound absorption coefficient SC of the sound absorption test piece C, and the sound absorption coefficient SC has a relationship of C>A> B. . That is, when examining the sound absorbing performance, it was found that the more the number of the communicating holes 2c formed in the partition wall 2b, the more the sound absorbing performance is reduced. It is considered that this is because, in the sound absorbing test pieces A to C whose front and back sides are open, the sound incident into the cell 2a is easily released through the communication hole 2c.
[0023]
On the other hand, as described above, when the sound insulating panels 1 and 10 are formed by laminating the plate members 3 and 3 on the front and back surfaces, the sound insulating performance is improved by forming the communication holes 2c. Has been confirmed. This is for the following reason. That is, as described above, the sound insulation performance of the sound insulation panels 1 and 10 of the present embodiment is improved by lowering the natural frequency of the cell 2 a and increasing the coincidence frequency of the sound insulation panels 1 and 10, as described above. This is based on the fact that the drop range of the sound pressure level difference ΔD due to the coincidence effect changes. Such a decrease in the natural frequency of the cell 2a and an increase in the coincidence frequency of the sound insulating panels 1 and 10 cannot be obtained only by forming the communication hole 2c in the partition wall 2b. Is obtained only in cooperation with the plate materials 3 and 3 laminated on the front and back surfaces.
[0024]
In the above-described embodiment, one or two communication holes 2c are formed in each partition 2b of the honeycomb core material 2 in order to improve the sound insulation performance of the sound insulation panels 1 and 10. The shape and number are not particularly limited, and can be freely set as long as the rigidity of the sound insulating panel 1 is not impaired. Further, the communication hole 2c is desirably formed in all the partition walls 2b, but it is not always necessary, and there may be a partition wall 2b in which the connection hole 2c is not formed. Also, each component of the sound insulation panel 1 shown in the embodiment is merely an example, and other appropriate materials can be adopted as long as the purpose of the present invention is met. In addition, the configuration of the details can be appropriately changed within the scope of the present invention.
[0025]
【The invention's effect】
As described above, the sound insulation panel of the present invention has effects such as obtaining better sound insulation performance.
[Brief description of the drawings]
FIG. 1 is a partially cutaway perspective view showing a sound insulation panel according to a first embodiment of the present invention.
FIG. 2 is a partial side view of the sound insulating panel of FIG.
FIG. 3 is a perspective view showing a situation where a communication hole is formed in a honeycomb core material.
FIG. 4 is a partial side view of a sound insulation panel according to a second embodiment of the present invention.
FIG. 5 is a diagram showing test results of sound insulation performance of (a) the sound insulation panel according to the first embodiment, (b) the sound insulation panel according to the second embodiment, and (c) a comparative example.
FIG. 6 is a schematic view showing a test method of the sound insulation performance of the sound insulation panel.
FIG. 7 is a diagram showing test results of sound absorbing performance of (a) a sound absorbing test body A, (b) a sound absorbing test body B, and (c) a sound absorbing test body C.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Sound insulation panel 2 Honeycomb core material 2a Cell 2b Partition wall 2c Communication hole 3 Plate material 10 Sound insulation panel

Claims (1)

A honeycomb core material having a number of cells independent of each other formed by partition walls, and a communication hole formed in the partition walls to communicate the cells,
A plate material having sound insulation properties laminated on the front side and the back side of the honeycomb core material,
A sound insulation panel comprising:

Images