JP2772217B2 - Sound insulation panel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound insulation panel in which a sound absorbing material is provided in a space between two face plates.

[0002]

2. Description of the Related Art As shown in FIG. 14, a conventional sound insulating panel is provided with a porous sound absorbing material 72 such as glass wool or urethane foam in a space between two facing surface plates 71, 71.
The panel 70 having a double structure is generally used, is lightweight, has relatively good sound insulation performance, and is practically used as a building panel.

However, the sound insulation panel having the double structure shown in FIG. 14 is not sufficient in sound insulation performance in a low frequency range. That is, since the sound absorbing coefficient of the porous sound absorbing material 72 in the low frequency range is low, the transmission loss in the low frequency range does not increase so much as compared with the case of the hollow double panel. In some cases, the local resonance transmission phenomenon causes a significant local decrease in transmission loss at a specific frequency (frmd). This point will be specifically described below.

As shown in FIG. 15, two surface plates 71, 7 are provided.
Hollow sound insulation panel 8 with 1 arranged at a distance of 75 mm
0, and two surface plates 71, 7 as shown in FIG.
1 with a spacing of 75 mm and a thickness of 25 mm
FIG. 17 shows the transmission loss at 100 to 4 kHz of the sound insulating panel 90 in which the glass wool is disposed as the porous sound absorbing material 72. In FIG. 17, the solid line represents the transmission loss of the sound insulation panel 80, the dashed line represents the transmission loss of the sound insulation panel 90, and the transmission loss of the sound insulation panel 90 is not so high in a low frequency range, and the transmission loss at the frequency frmd. Significant local declines in losses have occurred, confirming the results described above.

On the other hand, it is known that the frequency frmd follows the following equation (1).

[0006]

(Equation 1)

Here, ρ represents the density of air, c represents the speed of sound in the air, m represents the surface weight of the surface plates on both sides, and d represents the distance between the surface plates on both sides. From the above equation (1), the frequency f
In order to increase the transmission loss in 100 to 4 kHz, which is an important frequency band for architectural acoustics, by shifting rmd to 100 Hz or less, increase the distance d between the two face plates,
Alternatively, it is conceivable to increase the surface weight m of the surface plate.

[0008] However, if the distance between the surface plates is widened so that a considerable increase in transmission loss can be achieved, a very thick panel results. Further, if the surface weight of the surface plate is increased so as to achieve a reasonable increase in transmission loss, the panel becomes extremely heavy. Even if the surface weight is doubled, the sound insulation performance is improved only by about 6 dB.

[0009]

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a light-weight and thin sound-insulating panel which is excellent in sound-insulating performance in a low-frequency range.

[0010]

According to the present invention, there is provided a sound insulating panel having a sound absorbing material provided in a space between two facing surface plates, wherein powder is used as the sound absorbing material. The used sound absorbing material is used, and the sound absorbing material is housed in each of a plurality of frames that are open at least on two opposing surfaces, and these frames are not in contact with at least one surface plate. The openings are arranged along the direction parallel to the surface direction of the surface plate with a space between adjacent frame members, and each opening faces the space between the surface plates with a space in front.

Hereinafter, a sound insulating panel according to the present invention will be specifically described with reference to the drawings. 1 and 2
Represents a first configuration example of the sound insulation panel of the present invention. As shown in FIG. 1, the sound insulating panel 1 includes two facing surface plates 2 and 3, and a sound absorbing material 4 is housed in a frame 5 in a space between the two surface plates 2 and 3. It is arranged. A side plate 7 is provided at a peripheral end between the two front plates 2 and 3, and the width of the side plate 7 defines a distance between the front plates 2 and 3 to a predetermined dimension.

As shown in FIG. 2, each frame 5 has upper and lower openings 5a, and the upper opening 5a
And the lower opening 5b is spaced from the surface plate 3 by a gap G2.
The frame members 5 are arranged along a direction parallel to the surface direction of the surface plates 2 and 3 with a gap G3 between adjacent frame members 5. These frames 5 are not in contact with the upper surface plate 2.

As shown in the figure, the frame 5 has a lower opening 5.
Both edges of “b” are floating on the long floor board 21. The edge of the floor plate 21 itself also floats on the substrate 22, and a gap G 2 is formed between the frame body 5 and the surface plate 3 by the thickness of the floor plate 21 and the substrate 22. A partition plate 5c is provided at the center of the inside of the frame body 5, and the inside of the frame body 5 is divided into upper and lower parts, and the sound absorbing material 4 is accommodated in each part.

The openings 5a and 5b of the frame 5 are closed by an acoustically transparent sheet 6. Since the sound absorbing material 4 is a sound absorbing material using powder as will be described in detail below, the openings 5a and 5 are formed by an acoustically transparent sheet 6 so that the powder does not flow out.
It blocks b. What is acoustically transparent sheet 6?
A material having a sound transmittance of 0.8 or more in a frequency band of 4 kHz is suitable, and a permeable fabric, such as Saran cloth or glass cloth, or a thickness of about 0.05 m
m or less thin sheet, for example, polyethylene sheet,
Specific examples include a vinyl sheet. With such a sheet, the outflow of powder can be prevented without changing the sound absorbing characteristics of the sound absorbing material.

FIGS. 3 and 4 show a second configuration example of the sound insulation panel of the present invention. As shown in FIG. 3, the sound insulation panel 10 includes two facing surface plates 2 and 3, and the sound absorbing material 4 is contained in a frame 25 in a space between the two surface plates 2 and 3. It is arranged. A side plate 7 is interposed at a peripheral end between the two front plates 2 and 3, and the width of the side plate 7 is
The distance between the three will be defined to a predetermined size.

As shown in FIG. 3, each frame 25 has openings 25a to 25d on all four side surfaces, and each opening 25 faces an adjacent opening or side plate 7 with a gap. Each frame 25 is arranged along a direction parallel to the surface direction of the surface plates 2 and 3 with a gap between adjacent frames 25. Note that these frames 25 are not in contact with the upper surface plate 2. The openings 5 a and 5 of the frame 25 are also closed by the acoustically transparent sheet 6.

As shown in FIG. 4, each frame 25 has uprights 25h to 5k at the four corners of upper and lower plate members 25e and 25f, and is perpendicular to the surfaces of the plate members 25e and 25f inside the frame member 25. The partition plates 25m to 25o are erected in the direction of, and the inside of the frame 25 is divided into four spaces. The sound absorbing material 4 is stored in each space. Each opening 25a
25d are closed with an acoustically transparent sheet 6.

Both edges of the lower plate member of the frame body 25 are floating on the elongate floor plate 21. The end of the floor plate 21 itself also floats on the substrate 22 so that the floor plate 21 and the substrate 2
A gap is formed between the lower plate 25f and the surface plate 3 by the thickness of 2. The sound absorbing material 4 using powder may be composed of the following powder alone.

The powder used for the sound absorbing material of the present invention usually has a particle size of about 0.1 to 1000 μm and a bulk density of about 0.1 g / cm ³ to about 1.5 g / cm ³ . Gold mica powder, silica powder, acrylic ultrafine powder, talc powder, calcium silicate powder, fluororesin powder, perlite, bentonite, shirasu balloon, ishimatsuko, pullulan, fused silica powder , Graphite, crystalline cellulose powder, silicon carbide powder, diatomaceous earth, nylon powder,
Acrylic powder, polyester powder coating, wheat powder, dolomite powder, carbon fiber powder, titanium dioxide powder, calcium carbonate powder, vinyl chloride resin powder, polymethyl methacrylate powder, barium ferrite magnetic powder, silicone powder, etc. No. More specifically, there are the following.

That is, “the average particle size is 40 μm and the bulk density is
37g / cm^ThreeGold mica powder ”,“ Average particle size 1.7 to 150 μ
m and bulk density 0.06 to 0.28 g / cm^ThreeWet silica powder ”,
"Average particle size is 3-28 μm and bulk density is 0.31-0.92 g / cm^Threeof
Spherical silica powder ”,“ Dense bulk with average particle size of 1.5 to 9.4 μm ”
Degree 0.25-0.45g / cm^ThreeTalc powder ”,“ Average particle size 1 ~
0.3 μg / cm bulk density at 2 μm^ThreeAcrylic fine powder ”,
"Average particle size of 20 to 30 µm and bulk density of 0.08 g / cm^ThreeSilicic acid
Calcium powder ”,“ 100-150 μm average particle size and bulky
Degree 0.10-0.17g / cm^ThreePearlite powder ”,“ Average particle size
5 to 25μm and bulk density 0.37 to 0.45g / cm^ThreeFluororesin
Powder, average particle size 0.3-3.5 μm and bulk density 0.51--0.
74g / cm^ThreeBentonite powder ”,“ Average particle size 30-50μ
m and bulk density 0.20-0.32g / cm^ThreeShirasu Balloon ",
"Average particle size 35μm, bulk density 0.29g / cm^ThreeIshimatsuko ”,
"Average particle size 100 μm, bulk density 0.47 g / cm^ThreeNo pullla
”,“ Average particle size of 5.4 to 32 μm and bulk density of 0.55 to 0.77 g
/cm^ThreeFused silica powder ”,“ with an average particle size of 20 to 120 μm
Bulk density 0.26 to 0.73 g / cm^ThreeGraphite ”,“ Average particle size 10 ~
180 μm bulk density 0.28-0.32g / cm^ThreeCrystal Cellulose
Powder ”,“ average particle size 0.4 to 5.0 μm, bulk density 0.63 to
1.06g / cm^ThreeSilicon carbide powder ”,“ average particle size 3.2 μm
Bulk density 0.26g / cm^ThreeDiatomaceous earth ”,“ Average particle size 5-25
0 μm and bulk density 0.32 to 0.49 g / cm^ThreeNylon powder
ー ”,“ Average particle size 45μm, bulk density 0.63-0.67g / cm^Three
Acrylic powder ”,“ Average particle size 45μm, bulk density 0.54g
/cm^ThreePolyester powder ”,“ with an average particle size of 34 to 75 μm
Bulk density 0.45 to 0.51 g / cm^ThreeFlour ”,“ Average particle size 3
Up to 8 μm and bulk density 0.65 to 0.90 g / cm^ThreeDolomite powder
Body, ”average fiber diameter 14-18 μm, average fiber length 100-20
0.4 μm to 0.59 g / cm bulk density at 0 μm^ThreeCarbon fiber powder
Body ”,“ average particle size 0.1-0.25μm, bulk density 0.54-0.67
g / cm^ThreeTitanium dioxide powder ”,“ Average particle size 3 to 30 μm
Bulk density 0.60 ~ 1.04g / cm^ThreeCalcium carbonate powder
Body ”,“ average particle size 130μm, bulk density 0.53g / cm^ThreeSalt
PVC resin powder ”,“ Large with average particle size of 110 to 140 μm
Density 0.65g / cm^ThreePolymethyl methacrylate powder ",
"Average particle size 1.8-2.2 μm and bulk density 1.45g / cm ^ThreeNo ba
Lithium ferrite magnetic powder ”,“ with an average particle size of 0.3 to 0.7 μm
Bulk density 0.18-0.28g / cm^ThreeSilicon Powder "
I can do it.

Other examples include a structure of brass foil powder or magnesium silicate powder. The brass foil powder generally has a flake shape, and the flake diameter is about 1 to 100 μm and the thickness is about 0.1 to 2 μm. The structure of magnesium silicate powder refers to agglomerated particles of magnesium silicate short fibers. Generally, the average fiber diameter of the magnesium silicate short fibers is 0.1 to 0.5.
The average fiber length is about 5 μm to about 50 μm, but usually short fibers are aggregated to form aggregated particles of about 10 to 100 μm.

The sound-absorbing material 4 using the powder in the sound insulating panel of the present invention may have a configuration in which the above-described powder and the buffer material are mixed in a state where the powder can vibrate. The cushioning material used here is, for example, a nonwoven fabric, a fibrous structure, an artificial pulp, a filter paper, etc., having a thickness of 5 to 40 mm.
A sheet-like porous material having a thickness of about a suitable value is mentioned. Specifically, a polyester nonwoven fabric having a Young's modulus of about 2 × 10 ^{3 to} 3 × 10 ³ N / m, 1.3 × 10 ⁴
A nonwoven fabric made of a mixture of rayon, nylon, and polyester having a Young's modulus of about N / m may be used. In addition, polypropylene-based nonwoven fabric, polyurethane-based nonwoven fabric,
Nylon-based nonwoven fabrics and the like can also be used. If the thickness is small, a plurality of them may be overlapped. As the sheet-like porous material, besides the above-mentioned nonwoven fabric, for example, besides a fiber base material such as glass wool or rock wool, a foamed resin material such as urethane foam may be used. When the cushioning material is a sheet-like porous material, the mixed state of the powder and the cushioning material appears because the powder is introduced into the voids in the porous material.

The cushioning material is preferably in the form of a sheet because it is excellent in shape retention, but it is not necessarily required to be in the form of a sheet. In the case of the present invention, for example, it is a non-sheet-like (discrete) fibrous body, and can be mixed with the powder to reveal a mixed state of the powder and the buffer material,
A single material having a Young's modulus of 10 ⁵ N / m ² or less (for example, a non-sheet silicon carbide whisker) may be used as the cushioning material.

Hereinafter, the Young's modulus of a few cushioning materials will be specifically exemplified. “Glass wool 36K”: Young's modulus 7.8 × 10
⁴ (N / m ² ): density 3.6 × 10 ^-2 (g / cm ³ ) “synthetic pulp”: Young's modulus 2.0 × 10
³ (N / m ² ) (fiber length 100 μm): density 8.9 × 10
^-2 (g / cm ³ ) “Silicon carbide whisker”: Young's modulus 8.5 × 10
⁴ (N / m ² ): density 3.6 × 10 ⁻¹ (g / cm ³ ) “Polypropylene fiber: Young's modulus 1.4 × 10
² (N / m ² ) porous material ": density 2.4 × 10 ^-2 (g
/ Cm ³ ) In addition, a fibrous body in which a fine thread having a small diameter is entangled (along the longitudinal direction) with a core thread can also be used as a cushioning material. For example, as shown in FIG. 5, a fibrous body 121 in which a number of fine yarns 123 are entangled in a core yarn 122 along a longitudinal direction.
There is. The fine yarn 123 is a yarn having a smaller diameter (diameter) than the core yarn 122. Specifically, the diameter of the fine yarn 123 is usually about 1/3 to 1/20 of the diameter of the core yarn 122. .
The thicker core yarn 122 is preferably elastic, such as a polyurethane yarn. As a specific fiber body 121, for example, a polyurethane yarn (polyurethane fiber) having a diameter of 100 μm is used as a core yarn 122, and a nylon yarn (nylon fiber) having a diameter of 10 μm is entangled as a fine yarn 123 (true density 1. 19 g / cm ³ ).

As shown in FIG. 6, a mixed powder of a powder 13 made of a granular material and a powder 15 made of a fine fiber material is used as the powder. 5, or may be present in a void made of a fibrous body in which a fine thread having a small diameter is entangled with a core yarn as shown in FIG. As a configuration example of a mixed powder of a powder composed of a granular material and a powder composed of a fine fiber,
There are the following. “Powder formed by assembling“ silica powder having an average particle diameter of 150 μm ”as a powder made of a granular material and“ silicon carbide whisker (fine fibrous body) ”as a powder made of a fibrous material (average particle size of the aggregate) Powder having a diameter of about 50 μm) is mixed at a volume ratio of 1: 1. The above-mentioned granular material is not limited to a spherical shape, but includes various shapes other than a fibrous shape such as a plate (scale) shape, a square shape, a massive shape, and the like. What constitutes it is also mentioned. Of course, the microfibrous bodies may be individually discrete without cohesion. The whisker itself usually has an average length of 5 to 5.
Those having a diameter of 200 μm and an average diameter of about 0.05 to 1.5 μm are used. In addition, regarding the shape of the microfibrous body itself,
The shape is not limited to a linear shape, and may be, for example, a coil shape.

The powder may be such that it is adhered to the porous material in a vibrable state. For example, FIG.
As shown in FIG. 3, a thermoplastic resin 46 is applied to the surface of the powder 43 to form a heat-fusible surface on the powder 43 in advance, and is introduced into the voids of the porous material 41. Then, the thermoplastic resin 46 is melted, and as shown in FIG. 7, the thermoplastic resin 46 is bonded to the fibers 48 of the porous material 41 at positions A and B in part. The present invention is not limited to this. The thermoplastic resin 46 is applied to the fibers 48 to form a heat-fusible surface in advance, or the thermoplastic resin fibers are used as the fibers 48 to form a heat-fusible surface. May be made. The heat fusible surface may be formed on both the powder and the porous material. Further, the form of application of the thermoplastic resin 46 on the surface of the powder 43 may be a linear shape as shown in FIG. 9 or a fine particle shape as shown in FIG. As the thermoplastic resin, a polyvinyl resin, a polyamide resin,
Examples include polyester-based resins and polyurethane-based resins.

The sound absorbing material 4 using the powder in the sound insulating panel of the present invention may have a configuration in which the above powder and the porous layer are alternately laminated. A fiber sheet or the like can be used as the porous layer. The fiber sheet used for the porous layer has a thickness of about 0.2 to 2 mm. Of course, not all fiber sheets need to be the same thickness. As the type of the fiber sheet, a nonwoven fabric, a knitted fabric, a woven fabric, or the like having a mesh size smaller than that of powder particles is used. In other words, the fiber sheet has an average opening diameter smaller than the average particle diameter of the powder, and the powder easily enters the fiber sheet,
A material that does not allow the powder to easily pass through the fiber sheet is used. The fibrous sheet may be a laminate of a plurality of material sheets.

The use of the fiber sheet may make it easy for sound to pass through. For example, in the case of a resin sheet, the sound hardly passes through and is not suitable for a sound absorbing material. Since sound absorption is performed in the powder layer, the sheet itself needs to transmit sound to the powder layer without reflecting the sound. In the sound absorbing material of the present invention, the fiber sheet and the powder layer are alternately stacked, and the number of the powder layers is, for example, about 5 to 25, and usually about 10 to 20. If the number of layers is too small, the thickness per layer becomes large and it becomes difficult to stop the movement of the powder. If the number of layers is too large, the thickness per layer becomes small and the sound absorbing properties of the powder layer become insufficient.

FIG. 11 shows the sound absorption coefficient versus frequency characteristics of a 40 mm-thick powder layer made of magnesium silicate powder having an average aggregation diameter of 50 μm and a bulk density of 0.3 g / cm ³ . The frequency characteristic has a mountain shape with the sound absorption peak frequency fr at the center. The sound absorption mechanism of the powder layer is absorption by longitudinal vibration. The frequency fr is fr = (E / ρ) ^1/2 ÷ 4, where Young's modulus E of the powder layer, bulk density ρ, and powder layer thickness t are given.
It can be represented by t.

Examples of the frames 5, 25 of the sound insulation panel of the present invention include those made of aluminum, glass, rubber, wood, or acrylic or vinyl chloride resin. The frames 5 and 25 need not be entirely made of the same material, but may be made of a combination of different materials. The surface plates 2 and 3 of the sound insulation panel of the present invention include a metal plate such as an aluminum plate, a resin plate such as an acrylic plate, a wood plate such as a plywood, and an inorganic plate such as a gypsum board. The two face plates 2 and 3 may be made of the same material having the same thickness, but need not be the same thickness and need not be the same material.

[0031]

According to the sound insulation panel of the present invention, since the sound absorbing material provided in the space between the two surface plates is a sound absorbing material using powder, the sound absorbing panel is basically thin, lightweight and has a low frequency sound. It has sufficient sound insulation performance against This is because, in the case of a sound absorbing material using powder, due to the excellent sound absorbing effect of the powder, even a thin and light material has a sufficient sound absorbing effect on sound in a low frequency range.
The sound transmitted through the surface plate on the sound source side is almost absorbed by the sound absorbing material, and the sound coming out of the other surface plate is extremely reduced, so that sufficient sound insulation performance is secured. The sound insulation performance can be improved without increasing the weight of the face plates or increasing the distance between the face plates.

Moreover, in the sound insulating panel of the present invention, the sound absorbing material sufficiently exhibits the sound absorbing function, thereby making the sound insulating performance remarkable. The sound-absorbing material is divided into a plurality of parts, and the sound arriving in the space between the two face plates easily enters the sound-absorbing material through the gap between the frames or the gap between the surface plates and the frame, and the sound is absorbed. Cheap. Moreover, each frame body is opposed to two
The surface is at least open and faces the space between the face plates, is not acoustically shielded, and the sneaking sound is very easy to penetrate into the sound absorbing material in the frame.

Since the frame is not passed between the two surface plates and is always separated from one of the surface plates, sound propagation due to the transmission through the frame and powder vibration in the sound absorbing material are applied to the surface plate. The sound can be prevented from propagating by direct transmission.
It contributes to the improvement of sound insulation performance.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the sound insulation panel according to the present invention will be described below. Of course, the present invention is not limited to the following embodiments. Example 1 The sound insulation panel according to Example 1 has the panel configuration illustrated in FIGS. 1 and 2 described above.

In the frame 5 installed between the surface plates 2 and 3 in the sound insulating panel 1, the dimension between the acoustically transparent sheet 6 and the partition plate 5c of the openings 5a and 5b, that is, the thickness of the sound absorbing material 4 Is 40 mm. The gap G1 between the surface plate 2 and the opening 5a is 4 mm, the gap G2 between the surface plate 3 and the opening 5b is 4 mm, and the gap G between the frame 5 is 4 mm.
3 is 8 mm.

The sound absorbing material 4 contained in the frame 5 is a powder layer of magnesium silicate powder. This magnesium silicate powder has an average aggregate diameter of 50 μm and a bulk density of 0.3 g.
/ Cm ³ , and the powder has a normal incidence sound absorption coefficient as shown in FIG. 11 described above. In order to know the sound insulation performance of the sound insulation panel 1 of Example 1, a sound insulation panel having the same configuration except that the sound absorbing material 4 was not provided was manufactured, and the relationship between the frequency and the amount of improvement in the sound insulation performance was determined. The result is shown in FIG. As shown in FIG. 12, in the sound insulating panel 1 of Example 1, a remarkable improvement in the sound insulating performance is recognized around the frequency f1 substantially equal to the peak frequency fr of the magnesium silicate powder.

Example 2 The sound insulation panel according to Example 2 has the panel configuration shown in FIGS. 3 and 4 described above. In the sound insulation panel 10, in the frame 25 installed between the surface plates 2 and 3, the dimension between the acoustically transparent sheet 6 of the opening 5 and the partition plates 25m to 25o, that is, the thickness of the sound absorbing material 4 is 40 mm. is there. Also,
The gap between the surface plate 2 and the plate material 25e is 4 mm,
The gap between the surface plate 3 and the plate 25f is 4 mm, and the gap between the frame bodies 25 is 4 mm.

The sound absorbing material 4 housed in the frame 25 is also the same magnesium silicate powder layer as in the first embodiment.
In order to know the sound insulation performance of the sound insulation panel 10 of Example 1, a sound insulation panel having the same configuration except that the sound absorbing material 4 was not provided was produced, and the relationship between the frequency and the amount of improvement in the sound insulation performance was determined. FIG. 13 shows the results.
Shown in As shown in FIG. 13, the sound insulating panel 1 of the second embodiment
In the case of 0, a remarkable improvement in the sound insulation performance is recognized around a frequency f2 substantially equal to the peak frequency fr of the magnesium silicate powder.

In the case of the present invention, by appropriately designing the shape of the frame, the positional relationship between the opening (the surface of the sound absorbing material) and the surface plate, sound incident from one surface plate reaches the other surface plate. In the meantime, it is possible to make the structure that vibrates the powder of the sound absorbing material without fail, so that the excellent sound absorbing function of the powder can be maximized. In the case of the second embodiment, since the thickness direction of the sound absorbing material and the thickness direction of the sound insulating panel are perpendicular to each other, the thickness of the sound absorbing material is increased without increasing the total thickness of the sound insulating panel, and the frequency of the sound insulating peak is reduced to the low frequency side. It is also possible to shift to.

[0040]

According to the sound insulation panel of the present invention, since the sound absorbing material using powder is used, the weight of the surface plate can be increased,
The sound insulation performance can be improved without increasing the distance between the surface plates, and the sound absorbing material is divided into multiple parts, and the sound wraps around the gap between the frames and the gap between the surface plate and the frame. Since sound enters the sound absorbing material through at least two openings of the body, the sound is very easily absorbed by the sound absorbing material, and furthermore, sound propagation and powder vibration in the sound absorbing material transmitted through the frame are directly transmitted to the surface plate. Because of this, the propagation of sound is also prevented, so that it is lightweight and thin, and has excellent sound insulation performance in a low frequency range.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first configuration example of a sound insulation panel of the present invention.

FIG. 2 is a cross-sectional view illustrating a first configuration example of the sound insulation panel of the present invention.

FIG. 3 is a perspective view showing a second configuration example of the sound insulation panel of the present invention.

FIG. 4 is a perspective view showing a frame of the sound insulation panel of FIG. 3 with a part cut away.

FIG. 5 is an explanatory diagram showing a configuration example of a fibrous body in which a fine yarn is entangled with a core yarn.

FIG. 6 is an explanatory view showing a mixed powder composed of a granular body and a fine fiber body.

FIG. 7 is an explanatory view showing a powder thermally fused to a fiber.

FIG. 8 is an explanatory view showing an example of a powder in which a thermoplastic resin is adhered to the surface.

FIG. 9 is an explanatory view showing an example of a powder in which a thermoplastic resin is adhered to the surface.

FIG. 10 is an explanatory diagram showing an example of a powder in which a thermoplastic resin is adhered to the surface.

FIG. 11 is a graph showing sound absorption coefficient versus frequency characteristics of a sound absorbing material (powder layer) in an example.

FIG. 12 is a graph showing a relationship between a sound insulation improvement amount and a frequency of the sound insulation panel of Example 1.

FIG. 13 is a graph showing a relationship between a sound insulation improvement amount and a frequency of the sound insulation panel of Example 2.

FIG. 14 is a perspective view illustrating a configuration of a conventional sound insulation panel.

FIG. 15 is a cross-sectional view illustrating a configuration of a conventional hollow sound insulation panel.

FIG. 16 is a cross-sectional view illustrating a configuration of a conventional sound insulating panel provided with glass wool.

17 is a graph showing the transmission loss versus frequency characteristics of the sound insulating panels in FIGS.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sound insulation panel 2 Surface plate 3 Surface plate 4 Sound absorbing material 5 Frame 5a Opening 5b Opening G1 Gap G2 Gap G3 Gap

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) E04B 1/82 G10K 11/16

Claims (1)

(57) [Claims] 1. A sound insulating panel in which a sound absorbing material is provided in a space between two facing surface plates, wherein a sound absorbing material using powder is used as the sound absorbing material, and the sound absorbing material is at least The two opposing surfaces are accommodated in each of a plurality of open frames, and these frames are not in contact with at least one surface plate, and the surface plates are spaced apart from adjacent frame members. A sound insulation panel, wherein the openings are arranged along a direction parallel to the surface direction of the front panel, and each opening faces the space between the surface plates with a gap in front.