JPH0425864B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a laminated structure of rigid plates having excellent sound insulation properties.

(Prior Art) Laminated glass, sand German steel plates, sand German plaster boards, etc. are conventionally known as laminated structures of rigid plates having sound insulation and sound absorption effects. Laminated glass is made by bonding two sheets of glass together with a polyvinyl butyral interlayer, and Sandersch steel sheets are made by bonding two sheets of steel together via a thermoplastic resin with high viscoelasticity. Sand German plasterboard is made of two pieces of plasterboard bonded together with a highly viscoelastic rubber interposed therebetween.

The above-mentioned laminated glass, sanderch board, and sanderch plasterboard all have one intermediate layer 53 sandwiched between rigid plates 52, 52, as shown in FIG.

(Problems to be Solved by the Invention) However, in the above laminated glass, since the two sheets of glass are almost rigidly bonded, the coincidence effect of the constituent glass appears as it is, resulting in a drop in sound insulation performance. In that case,
Viscoelastic materials improve sound insulation performance by converting the deformation energy of rigid plates and plasterboards into thermal energy in the coincidence region.
Since the intermediate layer is one layer, it still does not have sufficient sound insulation performance.

An object of the present invention is to solve the above-mentioned problems, prevent a drop in sound insulation performance in the coincidence region of the rigid plates, and provide a rigid plate laminated structure having excellent sound insulation performance.

(Means for Solving the Problems) In order to solve the above technical problems, the present invention provides a rigid plate made by laminating two or more types of viscoelastic materials having different acoustic resistances between the rigid plates. It was made into a combined structure.

(Function) In a laminated structure in which an intermediate layer made of a viscoelastic material is bonded between rigid plates, the case where the intermediate layer is one layer will be explained based on FIG. 2.
2 and 12 are rigid plates, and a layer of viscoelastic material 13 is bonded between the rigid plates 12 and 12.
In the figure, the structure 11 is aligned by the sound wave 18 from the left side.
is subjected to bending deformation in the coincidence region, and the sound wave 18 is caused by the rigid plate 12 and the viscoelastic material 1.
Energy loss due to shear deformation a, a and internal energy loss due to deformation b of the viscoelastic material 13 itself are caused at the interface 15 with 3, and a part of the deformation energy of the entire combined structure 11 is converted into thermal energy. This absorbs the deformation of the rigid plate, thereby reducing the secondary radiation (transmission) 19 to the right of the laminated structure 11 and improving the sound insulation performance.

Furthermore, sound propagates through the laminated structure 11 as longitudinal waves, and since the specific acoustic resistances of the rigid plates 12, 12 and the viscoelastic material 13 are different, attenuation occurs due to reflection and absorption at the interfaces 15, 15, resulting in sound insulation performance. will improve.

Moreover, the areal density increases due to the increase in the weight of the viscoelastic material 13, and the sound insulation performance improves.

In the present invention, as shown in the action explanatory diagram of FIG. 3, the intermediate layer is composed of two or more types of viscoelastic materials 3 and 4 having different acoustic resistances, and the number of boundary surfaces 5, 6, and 7 is increased. By increasing the energy loss due to shear deformation a, a, a and reflection absorption at the interfaces 5, 6, 7, and using a material with a large loss coefficient as the viscoelastic material, the interfaces 5, 6, 7
By using two or more types of viscoelastic materials 3 and 4 with different specific acoustic resistances, the interface 6 between the viscoelastic materials is increased. Also, attenuation occurs due to reflection and absorption, and it is possible to prevent a drop in sound insulation performance in the coincidence region of the rigid plate.

(Example) Examples will be described below based on the accompanying drawings.

FIG. 1 is a sectional view of a rigid plate laminated structure according to the present invention, and in this embodiment, a case where the rigid plate is applied to a plate glass will be explained.

As shown in the figure, the rigid plate laminated structure 1 of this embodiment has a gap of 0.3mm between two glass plates 2, 2 with a thickness of 3mm.
A first intermediate layer 3 made of a thick methmethylacrylate resin and a second intermediate layer 4 made of a 1 mm thick vinyl chloride-ethylene glycidyl methacrylate resin are pressure-molded via an adhesive. The intermediate layer 3 and the second intermediate layer 4 are made of viscoelastic materials having different acoustic resistances.

In the above configuration, when the rigid plate lamination structure 1 undergoes bending deformation due to sound waves in the coincidence region, the boundary surface 5 which causes shear deformation due to the two types of viscoelastic materials 3 and 4 being laminated together,
6, 7 increases, energy loss occurs at each interface 5, 6, 7, and the two types of viscoelastic materials 3, 4
Since the acoustic resistances of the two waves are different, reflection and attenuation occur at the boundary surface 6, so that the energy of the incident sound wave can be greatly reduced.

The sound insulation effect is approximately 10 dB compared to the reduction in transmission loss due to the coincidence effect of 6 mm thick glass.
I have recovered.

Incidentally, since the coincidence frequency is inversely proportional to the thickness, in the above embodiment, the two glass plates 2,
By increasing the thickness difference between the glass plates 2 and 2, the coincidence areas of the glass plates 2 and 2 can be shifted to offset the coincidence effect, and the drop in sound insulation performance can be better recovered.

The thickness range of the viscoelastic material is preferably 0.1 to 5.0 mm; if it is smaller than the lower limit, it will have little effect on causing energy loss, and if it exceeds the upper limit, it will easily peel off.

Further, in the above embodiment, a case of plate glass was used as the rigid plate, but a steel plate such as a gypsum board or an asbestos board may also be used.

(Effect of the invention) The drop in transmission loss due to the coincidence region of the rigid plate is reduced, and the sound insulation performance is greatly improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of the rigid plate laminated structure of the present invention, FIG. 2 is an explanatory diagram of the operation when the intermediate layer is one layer,
Figure 3 is an explanatory diagram of the effect when the intermediate layer is two layers, and Figure 4
The figure is a sectional view of a conventional rigid plate lamination structure. 1 and 11 are a combination structure of rigid plates, 2 is a rigid plate,
3, 4, and 13 are viscoelastic materials, and 5, 6, 7, and 15 are interface surfaces.

Claims (1)

[Claims] 1. Different acoustic resistance between rigid plates 2.
A laminated structure of rigid plates characterized by laminating more than one type of viscoelastic material.