JPH09296534A - Sound absorbing composite panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound absorbing composite panel, having a high sound absorbing characteristic and easy to install, at a low cost. SOLUTION: A sound absorbing composite panel is formed of a rubber chip plate 1 and a synthetic plate 2 opposed to each other with a specified gap 4. The rubber tip plate used in this case is formed by crushing spent rubber of an old tire or the like into rubber chips of 1-5mm in grain diameter, mixing urethane resin serving as a binder in a range of 5-20wt.% into the rubber chips of 80-95wt.% and molding it into specified shape and size with a thickness of 1-50mm. It is desirable to add ultraviolet ray resistant material, a burning resistance imparting agent, and the like to the rubber chip plate 1 besides coloring pigment. Pores exist around the rubber chips, so that noise and rainwater can permeate to heighten a sound absorbing coefficient. The frequency area of noise can be coped with by changing the size of the gap and the material of the rigid plate, but a wider area of noise frequency can be coped with by interposing foam resin, glass wool or/and rock fiber in the gap.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a rubber chip plate formed by crushing a used rubber product such as an old tire by mixing urethane resin with a rubber chip plate, and an acoustically and rigidly rigid flat plate. The present invention relates to a sound-absorbing composite panel which is a combination of panels facing each other.

[0002]

2. Description of the Related Art As is well known, the present-day noise problem is positioned as a kind of pollution, and various preventive measures have been adopted in many situations. As part of such noise prevention measures, it is often adopted to install a sound absorbing panel toward the noise source to absorb the noise and reduce the damage of the noise to the living environment and the working environment.

The types of sound absorbing panels are roughly classified into those in which a fiber assembly or continuous foam material is bonded to a rigid plate, and those in which a Helmholtz resonator is constructed by using a rigid plate having many holes. Alternatively, a rigid plate and a void are combined to cause the rigid plate to resonate, and the internal loss caused by the resonance converts the energy of sound waves into thermal energy.

[0004]

Among the above-mentioned conventional techniques, in the case where a fiber assembly or a continuous foam material is used as a sound absorbing material used in a sound absorbing panel, these materials do not have a specific form. In addition, it has to be used in combination with some shape-retaining material that holds a predetermined shape or in combination with a binder, and there is a problem that it cannot be used as an independent sound absorbing structure.

Further, there are the following problems in the case of using a rigid plate having a hole or in the case of combining a rigid plate and a void to absorb the energy of noise. First, in the case where a large number of through holes and non-through holes are provided in a metal plate, the processing is troublesome, and the surface of the metal needs to be decorated within a range that does not reduce the sound absorption coefficient. Secondly, since the whole body is made of metal or concrete material, the weight of the sound absorbing panel becomes heavy, and the installation work becomes so troublesome that the safety work becomes more risky. Third
In addition, when these sound absorbing panels are used as so-called prefabricated products that are finished as pre-finished products in the factory, it is not possible to handle all of them in complex and diverse construction sites, and corners, corners and edges There are some parts that are not applicable to prefabricated products such as parts or curved parts, and there is a problem that it may not be possible to handle such situations.

[0006]

In order to solve the above problems, the sound absorbing composite panel of the present invention has a structure in which used rubber such as old tire is crushed into a predetermined average particle size as a constituent element, A rubber chip plate formed by mixing urethane resin into a predetermined shape and thickness was adopted. As a result, we have improved sound absorption, reduced costs such as raw material costs and ease of construction, and contributed to any noise prevention measures applicable to any construction site.

In the rubber chip plate, the average particle size of the rubber chips is set to 1 to 5 mm so that the moldability and the sound absorption coefficient and the strength are harmonized. Further, by setting the gap between the rubber chip plate and the base plate to be 10 to 300 mm, it is possible to cope with noise from a low frequency region to a high frequency region.

The rubber chip plate is a rubber chip 80-95w.
20 to 5 w of urethane resin as a binder for t%
By mixing t%, the cost of raw materials was reduced and the sound absorption coefficient and the strength were harmonized. When the rubber chip plate is manufactured in a factory, the cost is reduced by molding by compression molding or the like.

The noise absorption depends on the particle size of the rubber chip, the size of the small holes required around the rubber chip, the size of the gap between the rubber chip plate and the base plate, and the like. However, it is also possible to absorb the noise in a wide range of frequencies by filling the voids with a foaming resin to make the frequency range of sound absorption different.

Similarly, by interposing glass wool, rock wool, or both in this gap, it is possible to absorb noise in a frequency range of another range.

Further, the rubber chip plate can be molded at the construction site so that it can be applied to corners, corners or curved surfaces to meet all construction conditions, and the color can be unified. It was possible to maintain the uniformity of the surface appearance.

[0012]

1 shows an example of a sound absorbing composite panel according to the present invention. In a sound absorbing composite panel P, a rigid plate 2 is opposed to a back surface of a rubber chip plate 1, and a spacer 3 is provided at a predetermined interval. A void 4 is provided.

The rubber chip plate 1 is prepared by crushing used rubber such as old tires and having a mean particle diameter of 1 to 5 mm. It is made by pouring into, molding and solidifying. If the average particle size of the rubber chips is 5 mm or more, solidification molding becomes difficult, and the appearance of the molded product becomes conspicuous in terms of roughness and further weakened in strength, so it should be avoided.
Further, if the particle size is less than 1 mm, the appearance becomes smooth and the strength becomes stable, but the sound absorbing property is deteriorated, and therefore the meaning of using the rubber chip plate becomes less desirable, which is not preferable.

Next, the composition ratio of the rubber chip plate is such that the rubber chip is 80 to 95 wt% and the rest is urethane resin 20 to 5 wt%.
The one that has been adopted is adopted. The urethane resin may be a one-component urethane resin or a two-component urethane resin, but when the mixing ratio is 20 wt% or more, the strength becomes excellent. However, if the mixing ratio of the urethane resin becomes high, the space between the rubber chips will be filled up with the urethane phase, and the small pores that should exist between the particles of the rubber chips will be lost, and the sound absorption characteristics will deteriorate, so the composition ratio should exceed this. Should be avoided. Further, if the amount of urethane resin added is 5 wt% or less, the bonding strength between the rubber chips is lowered and it becomes unsuitable for use as a rubber chip plate, and therefore should be avoided.

The rubber chip plate is manufactured by mixing the above rubber chip with urethane prepolymer, stirring and mixing the raw material, pouring it into a mold having a predetermined shape and thickness, and holding it at room temperature for several tens of minutes to several hours. It is performed by curing. The curing time can be shortened by heating. During the mixing process of the rubber chips and the urethane prepolymer, rubber chips can be added by adding to them the same coloring pigments, flame retardancy-imparting materials, UV absorbers, antistatic agents, etc. It is possible to improve the characteristics according to the application of the plate.

The mold for molding the rubber chip plate may be made of wood, polyethylene, polypropylene or the like since the raw material is a material having a relatively low temperature. Therefore, when directly molding at the construction site, it is possible to mold into a shape corresponding to the actual situation at the construction site by forming a mold integrally with the rigid plate and the spacer and pouring the raw material into this.

The rigid plate 2 is required to have all of the following functions or selectively have them together. Part 1
As a function as a backing plate for fixing the sound absorbing composite panel to a wall or the like in a stable state. The second is a sound wave blocking function that reflects sound waves introduced into the sound absorbing composite panel without transmitting them. The third function is a holding function for fixing and holding the rubber chip plate.

In addition, since the sound absorbing composite panel is used outdoors by being exposed to wind and rain or sunlight, it is required to have various properties such as water resistance, shock resistance, ultraviolet light resistance, rust prevention and anticorrosion properties.
Further, it is also necessary to reduce the weight of the structure to be installed in order to reduce the burden on the structure and to facilitate the work.

Considering such functions, the rigid plate 2 is made of a material having a thickness of 1 mm to 50 mm, preferably 10 mm.
A ~ 40 mm metal plate or plastic, concrete, gypsum board, or sintered powder or granular material containing silicate can be used. In addition to this, as the material of the rigid plate, glass wool, rock wool, or the like, which is compressed and solidified, or the like can be used. Further, if necessary, a synthetic resin such as polyethylene, polypropylene, polystyrene, ABS, nylon, or polyester filled with an inorganic powder, or a mixture of several kinds of calcium carbonate, talc, clay, glass fiber, or the like is adopted. It is also possible. Further, the material of the rigid plate may be a combination of an inorganic board containing natural fibers or metal fibers, a vinyl chloride steel plate, a vibration-proof steel plate, a sandwich plate of aluminum and polyethylene, etc., if necessary.

The size of the gap 4 provided between the rubber chip plate 1 and the rigid plate 2 is 10 to 300 mm, preferably 20.
It is necessary to set the thickness to 200 mm. This void is 10
If it is less than mm, the sound absorption effect in the low frequency range becomes insufficient, and if it is more than 300 mm, the sound absorption rate in the high frequency range decreases, and the thickness of the entire panel becomes too large, which limits the handling and installation location. This is not desirable.

As an example of assembling the sound absorbing composite panel with the rubber chip plate 1 and the rigid plate 2, a member to be the spacer 3 at the time of molding the rubber chip plate is projected on the surface to be the inner side of the rubber chip plate, and the tip thereof is provided. There is one in which the portion is fixed to the rigid plate 2. Further, it is also possible to use a spacer made of plastic or metal to provide a gap so as to fix the both.

The sound absorbing composite panel thus manufactured is installed inside a sound insulating wall of a highway or on an inner wall of a factory with a lot of noise to absorb the noise and contribute to the improvement of the noise environment.

Next, another embodiment of the sound absorbing composite panel according to the present invention will be described. As another embodiment,
In order to change the frequency range of noise to be absorbed, it is effective to change the composition ratio of the rubber chip plate and the particle size of the rubber chip. Further, it is also effective that the rubber chip plate has two layers and the compression ratio at the time of molding is changed for each layer so as to have a width in the absorbable frequency range.

Further, in order to expand the frequency range of noise that can be absorbed, a foamed plastic plate having a predetermined thickness is interposed in the above-mentioned void (see FIG. 1) or a foamable resin is injected to foam. Further, it may be filled with crushed foamed plastic. As the foamable plastic, polystyrene, polypropylene, polyethylene, polyurethane or the like can be adopted. Further, when adopting these foaming plastics, various forms such as interposing them in the entire void, forming them partially or entirely, or making them porous are used. It can be selected and adopted.

Further, the gap between the rubber chip plate 1 and the rigid plate 2 may be filled with glass wool, rock wool, or both glass wool and rock wool in addition to the foam plastic. For glass wool and rock wool, ordinary commercial products can be used regardless of the diameter of each fiber. However, since these may absorb rainwater and reduce the sound absorbing effect, it is necessary to perform treatments such as sealing the four sides of the panel and improving drainage.

The size of the sound absorbing composite panel is determined in consideration of the efficiency of transportation and mounting work, and is 1 m × 1 m,
Besides a quadrangle such as 0.9 m × 1.8 m and 1.2 m × 2.4 m, a hexagon or a triangle having a predetermined size can be used.

Next, a construction for installing a soundproof wall by the sound absorbing composite panel according to the present invention will be described.

For example, it is assumed that a soundproof wall is installed in an urban area and the soundproof walls made of the sound absorbing composite panel according to the present invention are installed on both sides of a highway. In this case, if a soundproof wall having a height of 2 m from the road surface is installed, a rectangular sound absorbing composite panel of, for example, 2 m × 1 m in the straight part may be fixed to the wall with four corners by bolts. The properties of the sound absorbing composite panel are: UV resistance, rainwater resistance,
It is desirable to use a weather resistant one that is colored to match the road landscape. On the other hand, when installing this sound absorbing composite panel on a partition wall in a factory, it is provided so as to cover the entire wall surface, and if the installation height is about 5 to 8 m, the size corresponding to it Must be combined. Also, since it is indoors, it is not necessary to consider the influence of ultraviolet rays, but it is necessary to measure the frequency range of noise generated in the factory and adopt a sound absorbing composite panel corresponding to it. For the indoors, a rigid plate made of plastic having a small specific gravity is suitable, and it is desirable to select a suitable colored plate as the wall surface of the factory.

Next, a description will be given of how to directly manufacture or assemble the sound absorbing composite panel of the present invention at a construction site where the sound absorbing composite panel is installed. For example, as shown in FIG. 2 (a), when the wall surface of the construction site where the sound absorbing panel is installed has a curved surface, the sound absorbing composite panel manufactured in the factory cannot handle it. A rubber chip plate corresponding to a wall surface is molded using a mold.

In this embodiment, the spacer 23 is fixed along the wall surface 22 by using the anchor bolt 25 (see FIG. 2B). A net 26 capable of holding the raw material of the rubber chip plate is fixed to the tip of the spacer 23 to fix the gap 24.
Is provided.

Next, a support member 27 for supporting the mold is attached to the front surface of the net 26 and the surface facing the spacer 23. The support member 27 is formed of a synthetic resin material having a predetermined size, and is fixed to the front surface of the net 26 with an adhesive or the like. The inside of the form 28 is brought into contact with the tip of the support member 27, and a form capable of forming the thickness and shape of the rubber chip plate with the bolt 29 is provisionally provided.

Instead of this support member, as shown in FIG. 2 (b), a retaining bolt 30 may be used to hold the gap 21a between the net 26 and the form 28 at a desired size. With this configuration, a supporting member is not required, the number of parts is reduced accordingly, and installation is easy, which is advantageous in terms of construction cost.

Next, in the gap 21a defined between the net 26 and the form 28, the same characteristics and colors as those of the rubber chip plate 1 of the sound absorbing composite panel P installed on another straight wall surface are provided. A raw material capable of forming a rubber chip plate is poured and solidified. After the raw material is solidified, the mold 28 is removed, and the fixing bolts are screwed into the screw holes left after removing the temporary bolts 27 for temporarily setting the frame, thereby fixing the rubber chip plate 11 to the spacer 23. Completed a sound insulation wall that is consistent with the rubber chip plate of.

As the material of the above net, a raw material obtained by mixing a rubber chip and a urethane resin liquid is used as the gap 21.
A material that does not allow the rubber chips to pass through when poured into a and has a strength capable of holding the raw material is adopted. In addition, as the net material, those made of metal or plastic having a coarse mesh with excellent strength, a fine mesh capable of blocking the permeation of the rubber chip, or a laminated one of non-woven fabric or cloth May be adopted.

As the material of the mold, various rigid resin materials can be used in addition to wood. In particular, if a synthetic rubber plate having flexibility is adopted as the mold, it is possible to form a gap with a single mold over a large area.
It is also possible to facilitate the temporary construction of the formwork. It is desirable that a mold release agent such as silicone oil is applied to the mold frame in order to facilitate mold release from the rubber chip plate.

By adopting such a method of installing the sound absorbing composite panel, the color of the wall surface on which it is installed, the particle size of the rubber chips, etc. are finished in the same manner as the surrounding rubber chip plate, so that it is possible to construct without losing the uniform appearance. Becomes

[0037]

[Example] 60 kg of rubber chips (G grade, Kansai Tire Recycling Center Co., Ltd.) with an average particle size of 2.5 mm obtained by crushing used passenger car tires as raw materials for rubber chip plates, one-component urethane resin (Komatsu synthetic resin) 7.2 kg of AQUAMART U-1100B) and 2.0 kg of red pigment (Bayer Co., Red 110M) are adopted.
These raw materials were mixed in a stirring tank for about 5 minutes, and the mixture was filled in a mold having a substantially rectangular parallelepiped recess of 300 mm × 300 mm × depth of 18 mm.

Next, this is covered with a metal lid and compressed to a thickness of 14 mm, and while maintaining this state, it is heated in a heating furnace at 150 ° C. for about 3 minutes to cure the urethane resin,
After cooling, it is taken out and about 298 mm x 298 mm x 15 mm
To obtain a red substantially rectangular parallelepiped rubber chip plate.

Next, this rubber chip plate was formed into a plate having a thickness of 2 mm × 6.
30 mm on a rigid plate made of a 00 mm x 900 mm steel plate
× 30 mm, 50 mm thick polyethylene spacer material so that the gap between the rigid plate and the rubber chip plate is 50 mm, and the diameter of each rubber chip plate is 4 mm 3 mm ×
A sound absorbing composite panel was obtained by fixing the rubber chip plate at almost four corners with a round screw and a nut having a length of 70 mm.

(Measurement Example 1) In order to measure the sound absorption coefficient of this sound absorbing composite panel, as shown in FIG. 3, the sound absorbing composite panel includes a rubber chip plate 11 and a rigid plate 12 including one polyethylene spacer 13. In the shape of a disk with a diameter of 100 mm, and the cut rubber chip plate 11, polyethylene spacer material and rigid plate 12 are assembled with round screws and nuts (not shown) so that the distance 14 between them is 50 mm. And This sample is B & K (Bruel
When a vertical sound absorption coefficient was measured by using a 4206 type microphone impedance measuring tube 15 manufactured by KAIR) to set the iron plate surface of the sample in contact with the iron rigid surface of the device and sending sound from the direction of the arrow, A sound absorption coefficient curve as shown in FIG. 4 (a) was obtained. The maximum sound absorption coefficient at this time was about 99% at a frequency of 780.

(Measurement Example 2) In addition to the same conditions as those used in Measurement Example 1, expanded polystyrene 16 having an expansion ratio of 30 was used as a pulverized product having a diameter of about 5 mm to 10 mm, and this is filled almost completely in the space of the sample. Then, the vertical sound absorption coefficient was measured in the same manner as in Measurement Example 1, and a curve of the sound absorption coefficient as shown in FIG. 4B was obtained. The maximum sound absorption rate at this time is 644 Hz
The frequency was 98%.

(Measurement Example 3) The same measurement sample as that prepared in Measurement Example 2 was filled with about 16 g of glass fiber 17 having a diameter of about 1.5 μm in the inner space to a substantially full state, and the same as Measurement Example 2. The vertical sound absorption coefficient was measured as shown in Fig. 1.
A sound absorption coefficient curve as shown in (c) was obtained. In this example, the sound absorption coefficient on the low frequency side is improved, and the maximum sound absorption coefficient is 456.
It was 84% at a frequency of Hz.

In response to these results, a rubber chip disc having a diameter of 100 mm cut out from the rubber chip plate of Measurement Example 1 so as not to include the polyethylene spacer portion was used to measure the rigid surface of the measuring machine using the same apparatus as in Measurement Example 1. When the sound absorption coefficient was measured so that the back surface of the rubber chip was in contact with the rubber chip, that is, in the state where there was no air layer behind the rubber chip plate, a sound absorption coefficient curve as shown in FIG. 4D was obtained. As can be seen from this figure, the rubber chip plate itself is 10 in the frequency range of 1000 Hz or less.
Since it has a sound absorption rate of less than%, the rubber chip forming plate alone cannot substantially obtain the effect as a sound absorbing material.

[0044]

Industrial Applicability Since the present invention is composed of a rubber chip plate and a rigid plate made of used rubber such as old tires as a raw material, a sound absorbing composite panel which is inexpensive and has a high sound absorbing coefficient can be obtained while promoting recycling. .

Further, since the rubber chips constituting the rubber chip plate have small holes around them, a high sound absorbing property can be obtained and the infiltrated rainwater can flow out, so that the sound absorbing coefficient is lowered due to the infiltration of the rainwater. It will not occur.

If the rigid plate is made of a material such as plastic having a small specific gravity, the rubber chip plate having small holes is light in weight, so that it is possible to reduce the weight of the sound absorbing composite panel as a whole. It is easy to carry out, and there is an effect that the danger in work can be reduced.

When a rubber chip plate is molded, if a raw material to which a color pigment, a flame retardant-imparting material, or an ultraviolet resistant material is appropriately added is adopted, environmental beautification, fire prevention, or durability can be achieved depending on the use environment. It can be a sound-absorbing composite panel with excellent characteristics.

Also, by adjusting the distance of the gap between the rubber chip plate and the rigid plate, it is possible to adjust the noise absorption frequency over a wide range, so that it is possible to supply a sound absorbing composite panel corresponding to the type of noise.

Further, by interposing foam resin, rock wool, glass wool, or both rock wool and glass wool in the space between the rubber chip plate and the rigid plate, it becomes possible to change the frequency range of the noise to be absorbed. There is an effect that it can be used as a soundproof wall corresponding to a wide range of environments.

Furthermore, in some cases, a rigid plate can be used as a substitute for the wall of the construction site, and a formwork corresponding to curved surfaces and corners can be assembled at the construction site, so a sound absorbing wall that matches any construction site can be installed. It will be possible.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration example of a sound absorbing composite panel.

2A and 2B are a perspective view and a cross-sectional view showing a configuration example in the field construction.

FIG. 3 is a perspective view showing a state of voids in a sound absorption coefficient measurement experiment.

FIG. 4 is a diagram showing a relationship between frequency and sound absorption coefficient measured by a sound absorption coefficient measurement experiment.

[Explanation of symbols]

 1 Rubber chip board 2 Rigid board 4,24 Void 22 Wall surface 28 Form P Sound absorption composite panel

Claims (7)

[Claims] 1. A used raw material is obtained by crushing used rubber and mixing a rubber chip having an average particle size of 1 to 5 mm with a urethane resin as a binder at a predetermined ratio, and the raw material is small around the rubber chip. A rubber chip plate which is solidified into a state having holes and formed into a predetermined shape and size, and the rubber chip which can be installed on a wall surface and faces the back surface of the rubber chip plate and has a gap at a predetermined interval. A sound-absorbing composite panel comprising a rigid plate that holds the plate. 2. The sound-absorbing composite panel according to claim 1, wherein the raw material is a mixture of the rubber chips of 80 to 95 wt% and the urethane resin of 20 to 5 wt%. 3. The rubber chip plate according to claim 1, wherein the rubber chip plate is obtained by adding a color pigment and a flame retardant-imparting material and / or an ultraviolet resistant material to the raw material, if necessary. Sound absorbing composite panel. 4. The sound absorbing composite panel according to claim 1, wherein the gap is 10 to 300 mm. 5. The sound absorbing composite panel according to claim 1, wherein a foaming resin is interposed in the void. 6. The sound absorbing composite panel according to claim 1, wherein glass wool and / or rock wool is interposed in the void. 7. The rubber chip plate according to claim 1, wherein the rigid plate is substituted by a wall surface at a construction site, and the rubber chip plate is provided by using a form provided corresponding to the state of the wall surface. A sound absorbing composite panel characterized in that the sound absorbing panel can be directly installed at a construction site by forming the wall surface so as to have voids at predetermined intervals.