JPH0594195A - Sound insulation structure body and sound insulation/ sound absorption composite structure body - Google Patents

Abstract

PURPOSE:To provide the sound insulation structure body and the sound insulation/sound absorption composite structure body which are light in weight and thin, and also, large in its transmission loss extending over a wide frequency range. CONSTITUTION:The structure body consists of a surface material 71 of high regidity attached to a frame body 22, and sound absorbing materials 25, 26 packed to the inside or the outside of the surface material 71. As a means for increasing the rigidity of the surface material 71, a reinforcing material is provided, it is formed like a pyramid or like a curved surface, and also, a honeycomb-like material is used. In such a way, by enhancing the rigidity of the surface material 71, vibration of the surface material 71 is suppressed in a low frequency and a sound insulation loss by resonance transmission can be prevented. Also, in a high frequency, a fall of a transmission loss by solid propagation is prevented, and a high sound insulation performance is obtained extending over a wide frequency range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound-insulating structure and a sound-insulating / absorbing composite structure which are lightweight and thin, have high sound insulating performance, and are easy to construct.

[0002]

2. Description of the Related Art In recent years, with the improvement of living life, troubles related to noise have increased along with the effective use of space and an increase in interest in sound. Further, in the building industry, while the number of high-rise buildings has increased and prefabricated construction methods have spread, the shortage of skilled workers is becoming more serious. For this reason, there is a strong demand for a sound insulation structure that is lightweight, thin, and easy to construct.

By the way, the conventional sound insulation structure includes a concrete wall, a single wall made of masonry such as stones, bricks, and blocks, and a double wall in which plasterboard, plywood, etc. are doubly attached through columns and studs. Mainly used. 1
With regard to sound insulation by a heavy wall, the mass law that the sound transmission loss (D) and the surface density of the wall surface are proportional is well known. Also, multiple sound barriers are used to overcome the problem of mass law in single walls. For example, the transmission loss of a plate obtained by laminating two 24 mm thick plywood is 11 (Fig. 12).
As shown in Fig. 12, it rises at about 5 dB per octave, whereas when the above plywood is installed so as to become a completely independent double wall, as shown at 12 in Fig. 12, it is about 10 dB per octave. Rises at. Further, when the above plywood is installed with a gap of 30 mm, the sound insulation characteristic as shown in 13 of (FIG. 12) is obtained.

On the other hand, in order to realize a comfortable room acoustic space, appropriate sound absorption and reflection diffusion are required. However, a thick sound absorbing layer is required to effectively absorb low frequencies. Therefore, a structure in which a sound insulation layer and a sound absorption layer are combined is used. (FIG. 13) shows the structure of the conventional composite structure. (A) is an external perspective view, (b) is a cross-sectional view. Reference numeral 21 denotes a sound insulation / absorption composite structure (sound insulation panel) having a length of 90 cm, a width of 90 cm and a thickness of 10 cm, and holes 2 provided at four corners of the frame body 22.
A wall surface is formed by passing a bolt through No. 3 and fixing it to a frame (not shown). The surface material 24 of the panel is a composite plate in which lead of 1 mm thickness is sandwiched between plywood of 3 mm thickness and the areal density is 15 kg / m ² . The distance between the surface materials is 30 mm. Glass wool 25 having a thickness of 30 mm is provided between the surface materials, and glass wool 26 having a thickness of 50 mm is provided on the surface material on the indoor side. The transmission loss of this sound insulation panel is almost equal to 13 in (Fig. 12).

[0005]

However, the conventional sound insulation structure described above has the following problems. In order to realize a wall having a large transmission loss with a single wall, there is a problem that the weight of the wall becomes large. In addition, in order to secure the independence of the walls with the double walls, it is necessary to provide at least 20 to 30 cm of space between the walls, which causes a problem that the living space becomes small. Moreover, in practice, since the front and rear walls are joined by studs, it was impossible to make them completely independent walls.
In addition, when the space between the walls is small, a sound insulation defect due to resonance transmission occurs at the frequency represented by (Equation 1).

[0006]

[Equation 1]

Therefore, if the wall distance (l) is reduced,
The resonance transmission frequency (fc) becomes high, and a sound insulation defect occurs in important middle and high frequencies. For example, in the above example, a sound insulation defect occurs near 140 Hz.

In view of these problems, the present invention provides a sound-insulating structure and a sound-insulating and sound-absorbing composite structure which are lightweight and thin, have excellent workability, and have high sound-insulating performance.

[0009]

The sound insulation structure of the present invention comprises:
A frame body and a highly rigid surface material attached to the frame body,
A sound absorbing material provided between the front and back surface materials or outside at least one of the surface materials, and as a means for increasing the rigidity of the surface material, (1) a reinforcing material is provided,
(2) A pyramid shape or a curved surface shape, and (3) a honeycomb-shaped material are used.

[0010]

It is known that the transmission loss frequency characteristic of the sound insulating structure is determined by the stiffness of the structure at a low frequency and exhibits a higher transmission loss than the mass law. This is called the stiffness area. For example, (3 in Figure 14)
Reference numerals 1 and 32 show the relationship between the transmission loss and the frequency of honeycomb panels having different thicknesses. (Acoustic Engineering Course 3 Architectural Acoustics, Corona Publishing, p101). Due to the high rigidity of the panel, it shows higher transmission loss than the mass law at low frequencies. However, in the case of the honeycomb panel, since the surface materials are connected by the core, the sound propagates through the core as a sound bridge, and at a high frequency, the transmission loss is lower than that of the mass law.

According to the structure of the present invention, by increasing the rigidity of the surface material itself, it is possible to expand the stiffness region without connecting the surface materials to each other by the core, and it is possible to prevent sound insulation defect due to resonance transmission. Further, since the surface materials are independent, there is no reduction in transmission loss at high frequencies due to solid propagation unlike a honeycomb panel, and high transmission loss can be obtained over a wide range of frequencies. In addition, the sound absorbing characteristics in the high range are further improved by the sound absorbing material filled in the space of the core material.

[0012]

EXAMPLE An example of the present invention will be described below (FIG. 1). The outer shape and the structure of the surface material are the same as those described in the conventional example. Reference numeral 41 is a reinforcing material having a thickness of 24 mm and a width of 40 mm, which is firmly attached to one of the surface materials. Glass wool having a density of 48 kg / m ³ is filled between the surface materials, and glass wool having a density of 32 kg / m ³ is filled outside the surface material. The total weight is 30 kg and the equivalent areal density is 37 kg / m ² . When the sound insulation characteristics of this panel were measured (Fig. 2)
It became like 51. When the reinforcing material is not provided, a sound insulation defect due to resonance transmission is generated as shown by 52, but when the reinforcing material is provided, a large sound insulation defect does not appear in the measurement result. Further, when the front and back surface materials are connected by the reinforcing material, the transmission loss is reduced at a high frequency as indicated by 53. It should be noted that when both reinforcing materials are formed between the surface materials as shown in (FIG. 1), it is necessary to partially cut out the reinforcing material, but as shown in (FIG. 3), one of the reinforcing materials 41 is placed outside. If it is set up in, it will not be necessary.

Next, a second embodiment of the present invention will be described with reference to FIG. In FIG. 4, reference numeral 71 is a surface material formed of fiber reinforced plastic (FRP) and has a pyramid shape. The pyramid shape significantly improves rigidity as compared with a flat plate. Moreover, as a whole, since the volume of the outer sound absorbing layer 26 does not change, the sound absorbing performance hardly deteriorates. Moreover, a sound diffusion function can be provided by forming the surface material in a pyramid shape. Although only one of the surface materials has a pyramid shape in this embodiment, it is natural that both surface materials may have a pyramid shape as shown in (FIG. 5), and the shape may also be (FIG. 6), (FIG. 6). A structure having high rigidity such as a cylindrical shape or a spherical shell shape as shown in 7) or a rib as shown in FIG. 8 may be used.

Next, a third embodiment of the present invention will be described with reference to FIG. 121 and 122 are surface materials made of aluminum honeycomb, and a sound absorbing material 123 is filled in the core and inside the surface material. Further, the surface material on the outer side of the honeycomb 122 on the indoor side is provided with holes 131 as shown in FIG. In addition, the thickness of the surface material on the inside of the honeycomb 122 and the surface material on at least one side of the honeycomb 121 is increased in consideration of the design sound insulation performance. By providing the holes, the honeycomb structure, which is a surface material, can have a function as a sound absorbing body without substantially lowering the rigidity of the honeycomb structure.

Next, a fourth embodiment of the present invention will be described (see FIG. 1).
It will be described together with 1). The surface materials 141 and 142 are made of aluminum honeycomb, and the sound absorbing material is filled in the core as in the third embodiment. Also, the thickness of the surface material on the outside of the honeycombs 141 and 142 is the same as that of the third embodiment in that the thickness is increased in consideration of the design sound insulation performance. In this embodiment, holes 131 as shown in FIG. 10 are provided in the surface material on the inside of both honeycombs. By providing the holes, the gap D1 between the surface materials when the holes are not provided is substantially expanded to D2, the resonance transmission frequency is lowered, and the sound insulation performance is improved. Further, unlike the case where one honeycomb having a thickness of D2 is used, since the surface material is not connected by the core, the sound insulation performance at a high frequency is not deteriorated.
In addition, in the examples, all the double walls have been described, but the same applies to multiple walls of three or more.

Conventionally, in the multi-wall sound insulation structure, the construction cost and labor are required, and the low-frequency resonance transmission frequency is generated in a plurality of frequencies, so that the sound insulation defect may occur over a wide range of frequencies. Therefore, extremely high sound insulation performance is required, and it was used only when sufficient space between the wall surfaces could be secured. However, according to the configuration of the present invention, since the multiple walls are also integrally formed, the work at the site is no different from the case of constructing one panel. Moreover, as described above, due to the high rigidity in the low range, good sound insulation characteristics without sound insulation defects can be realized. Furthermore, in the mid-high range, the characteristics are triple-walled, and the transmission loss increases at 15 dB per octave, so extremely high sound insulation performance can be realized.

In the embodiment, the thickness of the core material and the surface material is constant, but by changing the thickness of the core material and the surface material, it is possible to prevent the deterioration of the sound insulation characteristics in the middle and high frequencies due to the coincidence effect. Is natural.

[0018]

As described above, the present invention comprises a frame body, a surface material having high rigidity attached to the frame body, and a sound absorbing material filled between the surface materials, and has a stiffness region in a transmission loss frequency characteristic. The sound insulation structure at low frequencies is prevented by expanding the sound absorption, and at the high frequency, the sound insulation defect due to solid propagation is prevented. be able to. Further, by providing the sound absorbing material on the outside of the surface material or in the core of the honeycomb-shaped surface material, a thin soundproof and sound absorbing composite structure can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of a first embodiment of the present invention.

FIG. 2 is a diagram showing a transmission loss frequency characteristic of the sound insulation structure according to the first embodiment of the present invention.

FIG. 3A is a perspective view of the first embodiment of the present invention in which one reinforcing material is provided outside the surface material, and FIG. 3B is a perspective view of the first embodiment of the present invention. Sectional view when reinforcing material is provided outside the surface material

FIG. 4 is a sectional view showing the configuration of a second embodiment of the present invention.

FIG. 5 is a cross-sectional view of a case where both surface materials are pyramid-shaped in the second embodiment of the present invention.

FIG. 6 is a cross-sectional view of the second embodiment of the present invention in which the surface material on one side is spherical.

FIG. 7 is a cross-sectional view in the case where the surface material on one side is made spherical in the second embodiment of the present invention.

FIG. 8 is a sectional view when a rib is provided on the surface material in the second embodiment of the present invention.

FIG. 9 is a sectional view showing the structure of a third embodiment of the present invention.

FIG. 10 is a diagram showing a state of holes formed in a surface material in the third embodiment of the present invention.

FIG. 11 is a sectional view showing the structure of a fourth embodiment of the present invention.

FIG. 12 is a diagram showing frequency characteristics of transmission loss of a conventional sound insulation structure.

FIG. 13A is a perspective view showing a configuration of a conventional sound insulation structure, and FIG. 13B is a sectional view showing a configuration of a conventional sound insulation structure.

FIG. 14 is a diagram showing frequency characteristics of transmission loss of a conventional honeycomb panel.

[Explanation of symbols]

11 Frequency characteristics of transmission loss of single wall 12 Frequency characteristics of transmission loss of completely independent double wall 13 Frequency characteristics of transmission loss of hollow double wall 21 Sound insulation panel 22 Frame 23 Hole 24 Surface material 25 Glass wool 26 Glass wool 31 Core Frequency characteristics of transmission loss of a honeycomb panel having a thickness of 25 mm 32 Frequency characteristics of transmission loss of a honeycomb panel having a core thickness of 60 mm 41 Reinforcing material 51 Frequency characteristics of transmission loss of a sound insulating structure according to an embodiment of the present invention 52 Implementation of the present invention In the example, the frequency characteristic of the transmission loss of the sound insulation structure without the reinforcement material 53 In the embodiment of the present invention, the frequency characteristic of the transmission loss of the sound insulation structure when the surface materials on both sides are connected by the reinforcement material 71 Pyramid shape Surface material 121 Surface material made of aluminum honeycomb 122 Surface material made of aluminum honeycomb 123 Glass wool 131 Hanika Surface material made of a surface material 142 aluminum honeycomb consisting of holes 141 aluminum honeycomb provided in the surface material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuei Sato 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (15)

[Claims] 1. A stiffness region composed of a frame, a surface material provided on both surfaces of the frame, and a sound absorbing material filled inside the surface material, wherein a stiffness region in a transmission loss frequency characteristic comprises:
A sound insulation structure characterized in that the rigidity of the surface material is increased so as to reach a frequency higher than the resonance transmission frequency determined by the surface density of the surface material and the distance between the surface materials. 2. The sound insulation structure according to claim 1, wherein a reinforcing material is provided on at least one of the surface materials. 3. The sound insulating structure according to claim 1, wherein at least one of the surface materials has a substantially pyramid shape, an arc shape, or a spherical shell shape. 4. The sound insulating structure according to claim 1, wherein at least one of the surface materials is a molded product integrally formed with a rib for reinforcement. 5. The sound insulating structure according to claim 1 or 3, wherein at least one of the surface materials is a honeycomb structure. 6. The method according to claim 1, wherein at least one of the surface materials is a honeycomb structure, and the surface material inside the honeycomb structure is provided with holes. The sound insulation structure described. 7. A frame, a surface material provided on both surfaces of the frame, a sound absorbing material filled inside the surface material, and a sound absorbing material provided outside at least one of the surface materials. The sound insulation is characterized by increasing the rigidity of the surface material so that the stiffness region in the transmission loss frequency characteristic reaches a frequency higher than the resonance transmission frequency determined by the surface density of the surface material and the distance between the surface materials. Sound absorbing composite structure. 8. The sound-insulating and sound-absorbing composite structure according to claim 7, wherein a reinforcing material is provided on at least one of the surface materials. 9. A sound absorbing material is provided outside at least one of the surface materials, and a part of the sound absorbing material is cut out, and a reinforcing material having a thickness equal to or less than the thickness of the sound absorbing material is provided on the cut surface. The sound-insulating and sound-absorbing composite structure according to claim 7. 10. At least one of the surface materials has a substantially pyramidal shape,
The sound-insulating and sound-absorbing composite structure according to claim 7, which has an arc shape or a spherical shell shape. 11. The sound-insulating and sound-absorbing composite structure according to claim 7, wherein at least one of the surface materials is a molded product integrally formed with a rib for reinforcement. 12. At least one of the surface materials has a substantially pyramidal shape,
8. The sound absorbing material is provided in a space surrounded by the frame and the surface material while having an arc shape or a spherical shell shape, and the surface of the sound absorbing material is substantially flat. Item 10. The sound-insulating and sound-absorbing composite structure as set forth in Item 10. 13. A sound absorbing material is provided in a space surrounded by a frame and the surface material, wherein at least one of the surface materials is formed by integrally forming ribs for reinforcement, and the surface of the sound absorbing material is substantially The sound insulating and sound absorbing composite structure according to claim 7, claim 10, claim 11 or claim 12, wherein the sound insulating and sound absorbing composite structure is a flat surface. 14. The honeycomb structure according to claim 7, wherein at least one of the surface materials is a honeycomb structure.
Alternatively, the sound-insulating and sound-absorbing composite structure according to claim 12. 15. The method according to claim 7, wherein at least one of the surface materials is a honeycomb structure, and holes are provided in the surface material on the outer side of at least one of the honeycomb structures. The sound-insulating and sound-absorbing composite structure according to claim 12 or 14.