JPH06158838A - Double floor - Google Patents

Abstract

PURPOSE:To enhance the sound insulation performance of a double floor at a resonance frequency band while meeting the required withstand load performance and strength, etc., by laying a powder layer with a specific resonance frequency between a floor base and a floor bed. CONSTITUTION:In a double floor comprising a floor base 1 and support legs 2 for supporting the floor base 1 to a floor bed 6, a powder layer 6 is laid between the floor base 1 and the floor bed 6. The powder layer 4 is formed by filling a thin box-shaped container 5 with baked vermiculite or the like, with its resonance frequency set to 90 to 350Hz. As a result, sound waves at an octave band of 90 to 350Hz emitted from the lower surface of the floor base 1 cause the powder 4 to resonate and this energy is damped inside the powder layer 4 so that the energy of the sound waves propagating toward the floor bed 6 is reduced. The sound waves of a sound pressure level as high as 90 to 350Hz octave band from the lower floor can then be absorbed between the floor base 1 and the floor bed 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floor material for constructing a double floor, and mainly to a technique for improving soundproof performance.

[0002]

2. Description of the Related Art In recent years, double floors have rapidly become popular because they can be installed under the floor in apartments and the like and have good workability. This product is laid so that a plurality of floor support legs, which are constructed by projecting support legs from multiple locations on the bottom surface of a floor base material, are placed next to each other by placing them on a floor base such as a concrete slab. The elastic rubber provided at the lower end of the support leg ensures soundproofness against floor impact.

[0003]

With respect to the double floor, the vibration of the floor base material passes through the supporting legs as a propagation path of the impact sound caused by the splash of a child, the walking of a human being, the fall of an object, or the like. It is considered that there are a route that is transmitted to the floor substrate and a route that sound emitted from the floor substrate propagates as a sound wave in the air layer between the floor substrate and the floor substrate to the floor substrate. In order to improve the soundproofness against impact noise, part of the support legs is made of vibration-proof rubber, or a sound absorbing material such as glass wool is laid in the air layer between the floor base material and the floor base, A measure is taken to absorb the airborne sound. However, if the elasticity of the anti-vibration rubber is reduced in order to improve the performance of the anti-vibration rubber, the rigidity of the entire floor is reduced, the load resistance is reduced, and the feeling of walking becomes poor. FIG. 5 shows the floor impact sound insulation performance of the double floor when the hardness of the anti-vibration rubber of the support leg is changed. Anti-vibration rubber hardness 50
Even if softened up to °, the floor impact sound level of the 125 Hz and 250 Hz octave bands is high, and the soundproofing performance is not improved so much. The broken line shown in FIG. I. S. Is a curve that defines the floor impact sound insulation performance of the soundproof floor. For example, if the sound pressure levels for each octave downstairs on a floor are all below the L-50 curve, the floor impact sound insulation performance of that floor is determined to be L-50. The smaller the value of L, the higher the soundproof performance.

The present invention is intended to provide a double floor with high soundproofing performance while satisfying basic performance such as load-bearing performance and strength by improving the sound insulation performance in the octave band frequency band from 90 Hz to 350 Hz. is there.

[0005]

SUMMARY OF THE INVENTION The gist of the present invention is to provide a double floor consisting of a floor base material 1 and supporting legs 2 for supporting the floor base material 1 on a floor base material 6, and Floor base material 6
The double layer is characterized in that the powder layer 4 is laid between the two and the resonance frequency of the powder layer 4 is set from 90 Hz to 350 Hz.

[0006]

[Operation] 3 from 125Hz emitted from the bottom surface of the floor base material
Sound waves in the 50 Hz octave band frequency band cause the powder layer to resonate. Since the powder layer has a large sound absorption coefficient near the resonance frequency, the sound wave energy in the frequency range above is attenuated in the powder layer, and the sound wave energy that propagates to the floor is reduced. The sound pressure level of the sound wave in the above-mentioned frequency band is lowered. In this way, the soundproofing performance of the floor is improved.

[0007]

Embodiment 1 FIG. 1 shows Embodiment 1 according to the present invention. A thin box-shaped container 5 having an upper surface opening for filling powder is arranged between the floor base material 1 and the floor base 6, and the burned flint stone 4 having an average particle diameter of about 100 μm is filled therein as the powder. I am doing it. The powder layer 4 has a thickness of 30 mm. Regarding the area of the container 5, it is easy to handle the area of about 150 mm square to about 1000 mm square. 2 is a support leg. The 30 mm-thick layer of the calcined hirucite resonates at about 280 Hz and exhibits a high sound absorption coefficient near 280 Hz as shown in FIG.

FIG. 3 shows another embodiment 2 according to the present invention. In this embodiment, as the powder constituting the laying powder layer 4, magnesium silicate having an average particle size of about 50 μm is used in addition to the calcined leucite having an average particle size of about 100 μm shown in Example 1. . The sound absorption coefficient of this magnesium silicate is shown in FIG. As can be seen from FIG. 4, there is a sound absorption peak near 190 Hz. The simultaneous use of the powder layer 42 of magnesium silicate and the powder layer 41 of calcined flint at the same time provides a sound absorbing effect in a wide frequency range.

Here, the powder used to form the powder layer is not limited to the calcined flint and magnesium silicate, but 90
A material having a resonance frequency in a frequency band from Hz to 350 Hz, that is, a material having a peak of sound absorption coefficient may be used.

The powder used in the present invention usually has a particle size of about 0.1 to 1000 μm and a bulk density of about 0.1 g / c.
It ranges from around m ³ to around 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, crystals Cellulose powder, silicon carbide powder, diatomaceous earth, nylon powder, acrylic powder, polyester powder, wheat flour, dolomide powder, carbon fiber powder, titanium dioxide powder, calcium carbonate powder, vinyl chloride resin powder, poly Examples thereof include methyl methacrylate powder, barium ferrite magnetic powder, and silicone powder. More specifically, there are the following.

That is, "gold mica powder having an average particle size of 40 μm and a bulk density of 0.37 g / cm ³ ", "average particle size 1.7
~150μm wet silica powder huge bulk density 0.06~0.28g / cm ³ "," spherical silica powder having an average particle size of 3~28μm bulk density 0.31~0.92g / cm ³ "," average particle The bulk density is 0.25 to 0.
45 g / cm ³ talc powder ”and the like.

Further, since the resonance frequency of the powder layer is inversely proportional to the layer thickness, the sound absorption effect can be obtained by laying several types having different thicknesses of the powder layer, that is, different peak frequencies of the sound absorption coefficient. It is also possible to widen a certain frequency band.

[0013]

INDUSTRIAL APPLICABILITY As described above, the double floor of the present invention absorbs sound waves of 90 to 350 Hz octave band, which has a high sound pressure level in the downstairs, between the floor base material and the floor substratum, so that the floor strength is high. It is possible to improve the soundproofing performance of the double floor without deteriorating the load resistance and the feeling of walking.

[Brief description of drawings]

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

FIG. 2 is a graph showing the sound absorption coefficient of the same.

FIG. 3 is a sectional view showing a second embodiment of the present invention.

FIG. 4 is a graph showing the sound absorption coefficient of the same.

FIG. 5 is a graph showing a sound absorption coefficient of a conventional example.

[Explanation of symbols]

 1 Floor base material 2 Support leg 3 Air layer 4 Powder layer 5 Container 6 Floor base

Claims (1)

[Claims] 1. A double floor comprising a floor base material 1 and supporting legs 2 for supporting the floor base material 1 on a floor base material 6, wherein a powder layer 4 is provided between the floor base material 1 and the floor base material 6. And a resonance frequency of the powder layer 4 is set from 90 Hz to 350 Hz.