Sound insulation structure and soundproof structure

Abstract

To provide a thin and lightweight sound insulation structure that achieves sufficient sound insulation and can be easily and stably placed on curved or uneven surfaces.SOLUTION: A sound insulation structure 1 comprises a membrane portion 2 having elasticity, support wall portions 3 having elasticity and erected on the membrane portion 2, and weight portions 7 erected on the membrane portion 2. The membrane portion 2 is divided into multiple compartments 5 by the support wall portions 3. One weight portion 7 is placed in one compartment 5 for all compartments 5 or in some of the compartments 5. The height of the support wall portion 3 is greater than the height of the weight portion 7. The membrane portion 2 functions as a spring element, and the weight portion 7 functions as a mass element, to constitute a spring-mass resonator. Each compartment 5 is sealed on the membrane portion 2 side by the membrane portion 2, and the weight portion 7 is located within space enclosed by the support wall portion 3. The support wall portion 3 has a dynamic storage elastic modulus of 0.01 MPa or more and 100 MPa or less at 23°C and a frequency of 1 Hz to 1000 Hz.SELECTED DRAWING: Figure 6A

Description

Technical Field

[0001] The present invention relates to a sound insulation structure and a soundproof structure.

Background Art

[0002] In recent years, in the interiors of buildings such as apartment houses, office buildings, and hotels, outdoor noises from automobiles, railways, airplanes, ships, etc. outside the building, equipment noises and human voices generated outside the room inside the building are blocked, and tranquility suitable for the use of the room is required. Also, inside vehicles such as automobiles, railways, airplanes, and ships, it is desired to reduce noise by blocking wind noise and engine noise to provide a quiet and comfortable space for passengers. Therefore, means for blocking the propagation of noise and vibration from the outside to the inside of buildings and vehicles, and also the propagation of noise and vibration from the outside to the inside within buildings and vehicles, that is, members with high soundproofing performance are required. In recent years, in buildings, lightweight soundproofing members have been required due to high-rise construction, etc., and also in vehicles, lightweight soundproofing members have been required for improving energy efficiency. Examples of soundproof structures forming soundproof walls in vehicles and buildings are disclosed in Patent Documents 1 to 6.

[0003] Patent Documents 1 and 2 disclose dash silencers (also called dash insulators) for automobiles. These dash silencers are laminated on a dash panel (dashboard) located at the boundary between the engine room and the passenger compartment, and suppress the entry of noise from the engine room into the passenger compartment. The dash silencer has a single-layer structure or a multi-layer structure containing felt or foamed urethane as a sound-absorbing material.

[0004] In the invention described in Patent Document 3, in an acoustic attenuation panel including a rigid frame divided into a plurality of individual cells, a sheet of a flexible material, and a plurality of weights, each weight is fixed to the sheet of the flexible material so that each cell is provided with a weight, and the attenuated sound is controlled by an appropriate selection of the mass of the weight.

[0005] In the invention described in Patent Document 4, in a soundproof material including an elastic sheet and a support portion that holds the sheet and partitions the sheet into partition portions, the relationship between the rigidity of the sheet in the partition portion and the surface density of the sheet is defined.

[0006] The sound insulation material of the invention described in Patent Document 5 is a structure including a flat substrate portion and a plurality of resonance portions that are connected to the substrate portion and have a predetermined resonance frequency. Each of the plurality of resonance portions has a weight portion and a connecting portion that connects the weight portion to the substrate portion. In a projection view seen from a direction perpendicular to the substrate portion, the center of gravity of the resonance portion is configured to be located outside the joint region between the substrate portion and the connecting portion.

[0007] The vibration reduction device of the invention described in Patent Document 6 has an acoustic metamaterial that is mounted on a vehicle body and blocks vibrations transmitted through the vehicle body, a cross-shaped frame that is mounted on the vehicle body and partitions a certain space into a certain region, and a vibrator that is configured at a corner portion of each region partitioned by the frame and has its own natural vibration frequency to block vibrations transmitted from the vehicle body through the frame.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Summary of the Invention

Problems to be Solved by the Invention

[0009] In the dash silencers described in Patent Documents 1 and 2, the noise entering the passenger compartment cannot be sufficiently reduced. In particular, the road noise transmitted from the ground to the passenger compartment is large, and there is a possibility that a quiet and comfortable space cannot be provided for the passengers.

[0010] The acoustic attenuation panel described in Patent Document 3 has a rigid frame that is not flexible, and vibrations are transmitted to the seat through this rigid frame, so sufficient sound insulation may not be obtained. Further, when the mounting surface on which the rigid frame is placed is curved or has irregularities, there is a possibility that the acoustic attenuation panel cannot be stably held. In particular, since panels of general vehicles (for example, automobiles) often have curved or irregular portions, it is difficult to simply use the acoustic attenuation panel of Patent Document 3 as a sound insulation material for vehicles. Further, the rigid frame has a large mass, and an increase in mass due to the sound insulation material may be a problem in vehicles.

[0011] The sound insulation material described in Patent Document 4 has a high support portion height, that is, a height extending in a direction orthogonal to the seat from the seat, and preferably is 25 mm or more. In order to stably support the seat by such a high support portion, the support portion preferably has rigidity. As a result, since vibrations are transmitted through the support portion, sufficient sound insulation may not be obtained, and it is difficult to mount it on a mounting surface having a curved surface or irregularities such as a panel of a vehicle (for example, an automobile). Further, such a high support portion causes an increase in the size and weight of the entire sound insulation material. When mounted on a panel of a vehicle or the like, there is a concern that the sound insulation material occupies a large space inside the vehicle, reducing the space efficiency and interfering with the installation of other members, or disturbing the passengers.

[0012] The sound insulation material described in Patent Document 5 has a resonance part, which is a functional part that exhibits a sound insulation effect, exposed without being covered by a support wall or the like. If another member or a human body comes into contact with this resonance part, there is a risk that the sound insulation performance will deteriorate or change. Therefore, it is necessary to provide a large space around the resonance part, resulting in a decrease in space efficiency.

[0013] The vibration reduction device described in Patent Document 6 does not have a film part and is composed of a plurality of vibrators and a frame connecting them. Therefore, similar to the sound insulation material of Patent Document 5, the vibrators, which are functional parts that exhibit a sound insulation effect, are exposed. If another member or a human body comes into contact with this vibrator, there is a risk that the sound insulation performance will deteriorate or change. In addition, in order to ensure the minimum structural strength of the vibration reduction device, the frame is required to have rigidity. As a result, there is a risk that sufficient sound insulation cannot be obtained because vibration is transmitted through the frame, and it is difficult to place the vibration reduction device of Patent Document 6 on a curved or uneven mounting surface such as a panel of a vehicle (e.g., an automobile).

[0014] Therefore, an object of the present invention is to provide a thin and lightweight sound insulation structure that can obtain sufficient sound insulation performance and can be easily and stably placed on a curved or uneven mounting surface such as a panel of a building, a mechanical device, or a vehicle (e.g., an automobile), and particularly has good sound insulation performance in the low-frequency region of 1000 Hz or less, and a soundproof structure including the same.

Means for Solving the Problems

[0015] The sound insulation structure of the present invention has an elastic film portion, a support wall portion that stands on the film portion and has elasticity, and a weight portion that stands on the film portion. The film portion is divided into a plurality of compartments by the support wall portion, and the weight portion is located inside all of the plurality of compartments or inside some of the plurality of compartments. In the compartment where the weight portion is located inside, one weight portion is arranged in one compartment. The height of the support wall portion extending in the direction perpendicular to the film portion is larger than the height of the weight portion extending in the direction perpendicular to the film portion. The film portion serves as a spring portion, and the weight portion serves as a mass portion to form a spring-mass resonator. Each of the compartments is sealed by the film portion on the film portion side, and the weight portion is located in a space surrounded by the support wall portion. The support wall portion is characterized in that the dynamic storage elastic modulus at 23°C in the frequency range of 1 Hz to 1000 Hz is 0.01 MPa or more and 100 MPa or less. Here, the elasticity referred to means the property of a solid substance deformed by an externally applied force to return to its original shape when the external force is removed, and includes energy elasticity and rubber elasticity (entropy elasticity). Here, the case of having at least one of energy elasticity and rubber elasticity (entropy elasticity) is referred to as "having elasticity". Both the film portion and the support wall portion may be made of any one of a material having no energy elasticity but having rubber elasticity, a material having no rubber elasticity but having energy elasticity, and a material having both rubber elasticity and energy elasticity. The film part may have a dynamic storage modulus at 23°C in the frequency range of 1 Hz to 1000 Hz of 0.01 MPa or more and 100 MPa or less. Further, both the film part and the support wall part may be made of an elastic body having a loss tangent at 23°C in the frequency range of 1 Hz to 1000 Hz of 0.01 or more and 0.50 or less. Specifically, the elasticity of the film part and the support wall part is evaluated by the dynamic storage modulus (E’) obtained by measuring the frequency dependence in the tensile or compression mode of a dynamic viscoelasticity measuring device in accordance with JIS K7244 and obtaining a master curve based on 23°C, and the dynamic storage modulus (E’) at 23°C in the frequency range of 1 Hz to 1000 Hz is 0.01 MPa or more and 100 MPa or less. More preferably, both the film part and the support wall part may be made of an elastic body having a dynamic storage modulus (E’) at 23°C in the frequency range of 1 Hz to 1000 Hz of 0.05 MPa or more and 50 MPa or less and a loss tangent at 23°C in the frequency range of 1 Hz to 1000 Hz of 0.05 or more and 0.45 or less.

[0016] The support wall part may include a plurality of first wall parts extending in a direction perpendicular to the film part and in a first direction parallel to the film part, and a plurality of second wall parts extending in a direction perpendicular to the film part and in a second direction perpendicular to the first direction. The area of each of the compartments may be 100 mm 2 or more and 1000 mm 2 or less. There may be provided 10 or more and 1000 or less of the compartments per 1000 cm 2 of the area of the film part, and it is more preferable that 50 or more and 500 or less of the compartments are provided. The support wall part may have a cylindrical shape with a circular, elliptical or oval cross-sectional shape defining each of the compartments, or a rectangular tube shape with a polygonal cross-sectional shape, specifically a square, regular pentagon or regular hexagon cross-sectional shape, defining each of the compartments. The plate thickness of the support wall part may be 0.5 mm or more and 5.0 mm or less, and more preferably 1.0 mm or more and 3.0 mm or less. The film thickness of the film part may be 0.1 mm or more and 3.0 mm or less. The height in the direction orthogonal to the film portion may be 5 mm or more and 20 mm or less. The height of the support wall portion extending in the direction orthogonal to the film portion may be 5 mm or more and 20 mm or less, and more preferably 10 mm or more and 20 mm or less. The support wall portion may be partially different in height. Having a plurality of the support wall portions, a part of the support wall portions may have a height extending in the direction orthogonal to the film portion higher than that of the other support wall portions. And the height of the support wall portion having a height extending in the direction orthogonal to the film portion may be greater than 10 mm and 20 mm or less, and the height of the other support wall portions (the support wall portions having a lower height) may be 10 mm or less. Here, the support wall portion having a high height refers to a support wall portion having a height higher (for example, 1 mm or more) than that of the other support wall portions (the support wall portions having a lower height). The height of the weight portion extending in the direction orthogonal to the film portion may be 1 mm or more. The durometer A hardness of the film portion may be 30 or more, and the durometer A hardness of the support wall portion may be 1 or more and 90 or less. The durometer A hardness can be obtained by measuring in accordance with JIS K 6253-3.

[0017] The sound insulation structure of the present invention is a sound insulation structure including a sound insulation plate-shaped portion and a sound shielding structure portion, the sound insulation plate-shaped portion is a plate-shaped member made of a sound absorbing material or a sound shielding material, the sound shielding structure portion is composed of a sound shielding structure having any of the above-described configurations, and at least one of the film portion and the support wall portion and the sound insulation plate-shaped portion are integrally formed or joined to each other, and the sound insulation plate-shaped portion and the sound shielding structure portion are positioned side by side in a plane. On the main surface of the sound insulation structure, the area occupied by the sound shielding structure portion may be 5% or more and 95% or less of the entire area of the sound insulation structure. At least one of the film portion and the support wall portion and the sound insulation plate-like portion may be integrally formed by insert molding, or may be joined to each other by any one of ultrasonic welding, adhesion with an adhesive, adhesion with an adhesive tape, fixing with a clip, a bolt, a staple or a rivet. Further, by devising the shape of the sound insulation plate-like portion or the sound insulation structure portion, a configuration in which the sound insulation structure portion and the sound insulation plate-like portion are joined to each other may be employed. For example, a fitting hole may be provided in the sound insulation plate-like portion, and a part of the film portion may be fitted into the fitting hole for joining. The sound insulation plate-like portion may have a single-layer structure composed of either a layer made of felt, urethane or glass wool, or a layer made of a resin film or a rubber sheet, or a multilayer structure in which they are laminated. This sound insulation structure may be attached to the interior panel of an automobile. Further, the sound insulation structure may be attached to the dashboard of the automobile, and sound insulation structure portions may be provided at positions facing the tires, respectively.

Advantages of the Invention

[0018] According to the present invention, there is provided a thin and lightweight sound insulation structure that can obtain sufficient sound insulation performance and can be easily and stably placed on a curved or uneven mounting surface such as a panel of a building, a machine device, or a vehicle (e.g., an automobile), and particularly has good sound insulation performance in a low frequency region of 1000 Hz or less, and a sound insulation structure including the same.

Brief Description of the Drawings

[0019]

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Mode for Carrying Out the Invention

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings. [First Embodiment] FIG. 1A is a perspective view of a sound insulation structure 1 according to a first embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line A-A of FIG. 1A and turned upside down vertically. The sound insulation structure 1 includes an elastic sheet-like film portion 2, a support wall portion 3 that stands substantially perpendicular to the film portion 2 and has elasticity, and a weight portion 4 that stands substantially perpendicular to the film portion 2. The film portion 2 is divided into a plurality of compartments (unit structures) 5 by the support wall portion 3. The weight portions 4 are respectively located inside all of the plurality of compartments 5 or inside some of the plurality of compartments 5. In the compartment 5 in which the weight portion 4 is located, one weight portion 4 is located in one compartment 5. FIG. 2A is an exploded perspective view of one compartment 5 of the sound insulation structure 1, and FIG. 2B is an exploded front view thereof. The height H1 of the support wall portion 3 extending from the film portion 2 in a direction perpendicular to the film portion 2 is greater than the height H2 of the weight portion 4 extending from the film portion 2 in a direction perpendicular to the film portion 2. Each of the weight portions 4 constitutes a spring-mass resonator having an elastic spring portion 4a and a mass portion (mass part) 4b having a mass larger than that of the spring portion 4a. The elasticity referred to here means the property of a solid substance deformed by an externally applied force to return to its original shape when the external force is removed, and includes energy elasticity and rubber elasticity (entropy elasticity). Here, the case of having at least one of energy elasticity and rubber elasticity (entropy elasticity) is referred to as "having elasticity".

[0021] The support wall portion 3 of the present embodiment includes a plurality of first wall portions 3a extending in a first direction D1 parallel to the film portion 2 and a plurality of second wall portions 3b extending in a second direction D2 orthogonal to the first direction D1. Specifically, the plurality of first wall portions 3a are arranged in parallel, and the plurality of second wall portions 3b are arranged in parallel. The first wall portion 3a and the second wall portion 3b are integrated at the intersection. In this way, the plurality of first wall portions 3a and the plurality of second wall portions 3b constitute a lattice structure, and a plurality of compartments 5 having a square planar shape partitioned by the first wall portion 3a and the second wall portion 3b are arranged in a matrix. In other words, the support wall portion 3 has a structure in which a plurality of square prism-shaped members having a square cross-sectional shape defining each compartment 5 are arranged side by side. The support wall portion 3 is preferably made of a flexible material such as rubber, elastomer, or resin foam. The flexible material referred to here is any one of a material having no energy elasticity but having rubber elasticity, a material having no rubber elasticity but having energy elasticity, and a material having both rubber elasticity and energy elasticity.

[0022] A portion of the weight portion 4 of the present embodiment on the side attached to the film portion 2 is a spring portion 4a, and a portion on the side opposite to the side attached to the film portion 2 is a mass portion 4b having a larger mass than the spring portion 4a. In the examples shown in FIGS. 1A to 2B, the spring portion 4a and the mass portion 4b have the same shape and the same dimensions, but different materials. The spring portion 4a is made of a flexible material, and the mass portion 4b is made of a material having a higher density than the material constituting the spring portion 4a. A spring-mass resonator is configured in which the spring portion 4a functions as a spring and the mass portion 4b functions as a mass. Note that, together with the spring portion 4a of the weight portion 4, the film portion 2 may also function as a part of the spring of the spring-mass resonator. Further, the air in the space surrounded by the film portion 2 and the support wall portion 3 may function as a part of the spring (air spring) of the spring-mass resonator. The spring portion 4a is also preferably made of any one of a flexible material, that is, a material having no energy elasticity but having rubber elasticity, a material having no rubber elasticity but having energy elasticity, and a material having both rubber elasticity and energy elasticity.

[0023] According to the sound insulation structure 1 of the present embodiment, the vibration of the film portion 2 is controlled by the action of the spring mass resonator constituted by the spring portion 4a and the mass portion 4b of the weight portion 4. In particular, in a specific frequency range (for example, a frequency of 1000 Hz or less which is the main frequency band of road noise in an automobile), the film vibration is significantly reduced. As a result, the radiated sound from the film portion 2 becomes small, and high sound insulation performance is exhibited.

[0024] In the partition 5 of the sound insulation structure 1 of the present embodiment, preferably 10 or more and 1000 or less are provided per 1000 cm 2 of the area of the film portion 2, and more preferably 50 or more and 500 or less are provided. If the number of partitions 5 is too small, the effect of dividing the entire sound insulation structure 1 into a plurality of partitions 5 and exhibiting the sound insulation effect for each partition is poor, and the sound insulation performance of the entire sound insulation structure 1 may be lowered. On the other hand, if the number of partitions 5 is too large, the weight of the entire sound insulation structure 1 may increase. The area of each planar shape of each partition 5 is preferably 100 mm 2 or more and 1000 mm 2 or less, and more preferably 200 mm 2 or more and 800 mm 2 or less. If the area of each planar shape of each partition 5 is too small, it may be difficult to arrange the weight portion 4 inside. On the other hand, if the area is too large, the effect of the weight portion 4 on the film portion 2 is poor, and the sound insulation performance may be lowered. The height of the entire sound insulation structure 1 in the direction orthogonal to the film portion 2 is preferably 5 mm or more and 20 mm or less. If the height of the entire sound insulation structure 1 is too low, the weight portion 4 may not have a sufficient height as a spring mass resonator. On the other hand, if it is too high, the weight of the entire sound insulation structure 1 may increase. Note that each drawing schematically shows each partition 5, the support wall portion 3, etc. There may be cases where the number and area of the partitions 5 and the height of the sound insulation structure 1 are not strictly and accurately shown, or are not unified in each drawing. However, it is preferable that the number and area of the partitions 5 and the height of the sound insulation structure 1 are appropriately designed so as to be within the numerical ranges described above.

[0025] The film portion 2, the support wall portion 3, and the spring portion 4a of the sound insulation structure 1 of the present embodiment are all made of an elastic body having a dynamic storage modulus (E') of 0.01 MPa or more and 100 MPa or less and a loss tangent (tan δ) of 0.01 or more and 0.50 or less at a frequency of 1 Hz to 1000 Hz at 23°C. Preferably, the dynamic storage modulus (E') is 0.05 MPa or more and 50 MPa or less and the loss tangent (tan δ) is 0.05 or more and 0.50 or less at a frequency of 1 Hz to 1000 Hz at 23°C. The dynamic storage modulus (E') and the loss tangent (tan δ) are obtained by creating a master curve based on 23°C using a dynamic viscoelasticity tester. If the dynamic storage modulus (E') at a frequency of 1 Hz to 1000 Hz at 23°C is less than 0.01 MPa, the sound insulation performance in the target frequency band may deteriorate, and the shape retention of the film portion 2 and the support wall portion 3 may also deteriorate. If the dynamic storage modulus (E') at a frequency of 1 Hz to 1000 Hz at 23°C is greater than 100 MPa, the vibration in the sound insulation target frequency band may deteriorate, and the sound insulation structure 1 may become rigid and the installability may also deteriorate. The film portion 2 and the support wall portion 3 may be formed of the same material or different materials. The film portion 2 is preferably made of any one of a flexible material, that is, a material having no energy elasticity and having rubber elasticity, a material having no rubber elasticity and having energy elasticity, and a material having both rubber elasticity and energy elasticity.

[0026] The diaphragm part 2 is preferably a relatively hard elastic film since the hammer part 4 is attached thereto. The dynamic storage elastic modulus (E’) of the diaphragm part 2 is preferably 15 MPa or more, the thickness (film thickness) is preferably 0.1 mm or more and 3.0 mm or less, and more preferably about 0.5 mm. If the thickness of the diaphragm part 2 is less than 0.1 mm, the vibration of the diaphragm part 2 may deteriorate, and the sound insulation property in the frequency band to be sound-insulated may deteriorate. If the thickness of the diaphragm part 2 is greater than 3.0 mm, the thickness and weight of the entire sound insulation structure 1 may increase. The material of the diaphragm part 2 preferably has a durometer A hardness of 30 or more according to JIS K6253, and more preferably 70 or more. If the durometer A hardness of the diaphragm part 2 is less than 30, the vibration of the diaphragm part 2 may deteriorate, and the sound insulation property in the frequency band to be sound-insulated may deteriorate. And the rigidity (axial rigidity) k of the diaphragm part 2 is expressed as k = E’ × A / L from the dynamic storage elastic modulus E’, the cross-sectional area A, and the thickness L of the diaphragm part 2. When the area of the diaphragm part 2 to be evaluated for rigidity is 1000 cm 2 when, the rigidity k is preferably 10 6 N / mm or more and 10 9 N / mm or less, and more preferably 3×10 6 N / mm or more and 10 8 N / mm or less. If the rigidity when the area of the diaphragm part 2 is 1000 cm 2 is less than 10 6 N / mm, the vibration of the diaphragm part 2 may deteriorate, and the sound insulation property in the frequency band to be sound-insulated may deteriorate. If the rigidity when the area of the diaphragm part 2 is 1000 cm 2 is greater than 10 9 N / mm, the sound insulation structure 1 may become rigid and the installability may deteriorate. Further, the bending rigidity K of the diaphragm part 2 is expressed as K = E’ × I from the dynamic storage elastic modulus E’ and the second moment of area I. The second moment of area I is calculated as I = b × h 3 / 12 from the thickness h and the width b of the diaphragm part 2. When the area of the diaphragm part 2 to be evaluated is 1000 cm 2 when, the bending rigidity K is preferably 30 N / mm 2 or more and 10 5 N / mm 2 or less, and preferably 50 N / mm 2 or more and 5×104 N / mm 2 It is more preferable that the following holds. When the area of the film part 2 is 1000 cm 2 and the bending rigidity K is less than 30 N / mm 2 , the vibration of the film part 2 may deteriorate, and the sound insulation performance in the frequency band to be sound-insulated may deteriorate. When the area of the film part 2 is 1000 cm 2 and the bending rigidity K is greater than 10 5 N / mm 2 , the sound insulation structure 1 may become rigid and the installability may deteriorate. The cross-sectional shape of the film part 2 is not particularly limited, and it may be flat or may have irregularities.

[0027] Examples of the material of the diaphragm part 2 include crosslinked (vulcanized) rubber, thermoplastic elastomer, and plastic. Examples of the crosslinked (vulcanized) rubber include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), butyl rubber (IIR), nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), and ethylene-butene-diene rubber (EBDM) such as ethylene·α-olefin·non-conjugated polyene copolymers, chlorosulfonated polyethylene (CSM), chlorinated polyethylene (CM), acrylic rubber (ACM), ethylene-acrylic rubber (AEM), ethylene-vinyl acetate rubber (EVA), epichlorohydrin rubber (CO, ECO), polysulfide rubber (T), silicone rubber (Q) such as methyl vinyl silicone rubber (VMQ) and fluorinated silicone rubber (FVMQ), urethane rubber (U), and various rubber materials such as fluororubber (FKM) crosslinked (vulcanized). These crosslinked (vulcanized) rubbers can be used alone or in combination of two or more. Note that as the crosslinking (vulcanizing) method, for example, a method of crosslinking (vulcanizing) by heating using an organic peroxide, phenol resin, oxime compound, sulfur, sulfur-based compound, or polyamine compound as a crosslinking agent (vulcanizing agent), or a method of crosslinking by irradiating with an electron beam can be mentioned. Note that the crosslinked (vulcanized) rubber may generally be compounded with various known compounding agents (reinforcing agents such as carbon black and silica, fillers such as calcium carbonate, softening agents such as paraffin oil and plasticizer, processing aids, antioxidants, light stabilizers, flame retardants, antifungal agents, acid acceptors, silane coupling agents, antistatic agents, ultraviolet absorbers, etc.) used as rubber compounding agents. These crosslinked (vulcanized) rubbers, crosslinking agents (vulcanizing agents), and compounding agents may be made of biomass raw materials.

[0028] Examples of the thermoplastic elastomer include olefin-based thermoplastic elastomers, styrene-based thermoplastic elastomers, polyester-based thermoplastic elastomers, polyvinyl chloride-based thermoplastic elastomers, ethylene-vinyl acetate-based thermoplastic elastomers, and the like. Examples of the plastic include polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, or a composite resin containing them. These thermoplastic elastomers and plastics may be made of biomass raw materials.

[0029] Specifically, the material of the film part 2 is preferably ethylene-propylene-diene rubber, thermoplastic olefin-based elastomer, thermoplastic styrene-based elastomer, polyethylene, polypropylene, polyethylene terephthalate, thermoplastic polyurethane, or the like.

[0030] The support wall portion 3 is preferably made of a soft and flexible material within a range capable of supporting the film portion 2. The plate thickness of the support wall portion 3 is preferably 0.5 mm or more and 5.0 mm or less, more preferably 1.0 mm or more and 3.0 mm or less. If the plate thickness of the support wall portion 3 is less than 0.5 mm, the shape retention of the sound insulation structure 1 may deteriorate. If the plate thickness of the support wall portion 3 is greater than 5.0 mm, the vibration of the film portion 2 may deteriorate, and the sound insulation performance in the frequency band to be sound-insulated may deteriorate, and the weight of the entire sound insulation structure 1 may also increase. The height of the support wall portion 3 extending in a direction perpendicular to the film portion 2 is preferably 5 mm or more and 20 mm or less, more preferably 10 mm or more and 20 mm or less. The support wall portion 3 may be partially different in height. When the height of the support wall portion 3 is partially different, the higher portion of the height may be 10 mm or more and 20 mm or less, more preferably 12 mm or more and 20 mm or less, and even more preferably 14 mm or more and 20 mm or less. If the height of the support wall portion 3 is too low, the weight portion 4 may not have sufficient height as a spring mass resonator. If the height of the support wall portion 3 is too high, the overall weight may increase. The material of the support wall portion 3 preferably has a durometer A hardness of 1 or more and 90 or less according to JIS K6253, more preferably 10 or more and 70 or less. If the durometer A hardness of the support wall portion 3 is less than 1, the shape retention of the sound insulation structure 1 may deteriorate. If the durometer A hardness of the support wall portion 3 is greater than 90, the vibration from the support wall portion 3 may be transmitted to the film portion 2, the sound insulation performance may deteriorate, and the sound insulation structure 1 may become rigid and the installability may deteriorate. And the rigidity k of the support wall portion 3 is expressed as k = E'×A / L from the dynamic storage modulus E', the cross-sectional area A of the support wall portion 3, and the height L of the support wall portion 3. When the area of the support wall portion 3 to be evaluated for rigidity is 1000 cm 2 When it is, the rigidity k is preferably 10 N / mm or more and 10 6 N / mm or less, and more preferably 10 2 N / mm or more and 10 5 N / mm or less. When the area of the support wall portion 3 is 1000 cm 2When the rigidity k is less than 10 N / mm, the shape retention of the sound insulation structure 1 may deteriorate. When the area of the support wall portion 3 is 1000 cm 2 and the rigidity k is 10 6 greater than N / mm, the vibration from the support wall portion 3 is transmitted to the film portion 2, the sound insulation performance deteriorates, and the sound insulation structure 1 may become rigid and the installability may deteriorate.

[0031] Examples of the material of the support wall portion 3 include crosslinked (vulcanized) rubber, thermoplastic elastomer, resin foam, etc. The crosslinked (vulcanized) rubber and thermoplastic elastomer may be the same as the materials listed as the material of the film portion 2. The resin foam may have an open cell structure or a closed cell structure, and examples include polyurethane foam, polystyrene foam, polyethylene foam, ethylene-vinyl acetate rubber (EVA) foam, etc. Specifically, the material of the support wall portion 3 is preferably ethylene-propylene-diene rubber, urethane rubber, silicone rubber, thermoplastic olefin-based elastomer, thermoplastic styrene-based elastomer, thermoplastic polyurethane, polyurethane foam, etc. These resin foams may be made of biomass raw materials.

[0032] The material of the spring portion 4a of the weight portion 4 is a flexible material such as crosslinked (vulcanized) rubber, thermoplastic elastomer, resin foam, etc. The crosslinked (vulcanized) rubber, thermoplastic elastomer, and resin foam may be the same as the materials listed as the material of the support wall portion 3. Specifically, the material of the spring portion 4a of the weight portion 4 is preferably ethylene-propylene-diene rubber, urethane rubber, silicone rubber, thermoplastic olefin-based elastomer, thermoplastic styrene-based elastomer, thermoplastic polyurethane, polyurethane foam, etc.

[0033] The material of the mass portion 4b is not particularly limited, and it may be made of resin, metal, or the like. The mass portion 4b has a greater mass than the spring portion 4a and has a mass of, for example, 0.1 g or more and 2.0 g or less. Preferably, the mass portion 4b has a mass that is at least twice the mass of the spring portion 4a. If the weight of the mass portion 4b is less than twice the mass of the spring portion 4a, the weight portion 4 may not be sufficiently resonated in the frequency range to be sound-insulated, and the sound-insulating property may deteriorate. When the material of the mass portion 4b is resin, the resin may be made of biomass raw materials.

[0034] The spring constant (rigidity) of the spring portion 4a is determined based on the mass of the mass portion 4b so that the resonance frequency matches the frequency that is the main sound-insulation target. As an example, when the mass of the mass portion 4b is 1.0 g and the frequency that is the main sound-insulation target is 1000 Hz or less, the spring constant of the spring portion 4a is 1 N / mm or more and 50 N / mm or less.

[0035] With such a configuration, each of the film portion 2, the support wall portion 3, and the weight portion 4 is relatively lightweight, and the dimension in the direction orthogonal to the film portion 2 is relatively small. Thus, although the sound-insulating structure 1 of the present embodiment is lightweight and thin, as described above, high sound-insulating performance can be obtained in a specific frequency range (for example, 1000 Hz or less). And, the support wall portion 3 made of a flexible material can be easily and stably installed without being fixed to a flat mounting surface, a curved mounting surface, or a mounting surface having irregularities by adhesion or the like.

[0036] FIG. 3A is a perspective view of a sound insulation structure 1 according to a modification of the first embodiment of the present invention, and FIG. 3B is a cross-sectional view taken along line A-A of FIG. 3A and inverted vertically. FIG. 4A is a cross-sectional view of a sound insulation structure 1 according to another modification, and FIG. 4B is a perspective view of a weight portion 4 of the sound insulation structure 1. FIG. 5A is a cross-sectional view of a sound insulation structure 1 according to still another modification, and FIG. 5B is a perspective view of a weight portion 4 of the sound insulation structure 1. In these modifications, the spring portion 4a and the mass portion 4b of the weight portion 4 have different shapes and different dimensions. In the modification shown in FIGS. 3A and 3B, the spring portion 4a is a small-diameter cylindrical shape, and the mass portion 4b is a large-diameter cylindrical shape. In the modification shown in FIGS. 4A and 4B, the spring portion 4a is an elongated cylindrical shape, the mass portion 4b is a spherical shape, and the diameter of the cross-sectional shape of the cylindrical spring portion 4a is smaller than the diameter of the spherical mass portion 4b. In the modification shown in FIGS. 5A and 5B, the spring portion 4a is a frustum of a cone shape, the mass portion 4b is a cylindrical shape, and the diameter of the minimum portion of the frustum of a cone-shaped spring portion 4a substantially coincides with the diameter of the cylindrical mass portion 4b. In the modifications shown in FIGS. 3A to 4B, the mass portion 4b has a larger volume than the spring portion 4a. Therefore, even if the spring portion 4a and the mass portion 4b are formed of the same material, the mass portion 4b has a larger mass than the spring portion 4a and can constitute a spring mass resonator. However, in this modification, the spring portion 4a and the mass portion 4b may be formed of different materials and the mass portion 4b may have a larger mass than the spring portion. On the other hand, in the modification shown in FIGS. 5A and 5B, the spring portion 4a has a larger volume than the mass portion 4b. In this case, the mass portion 4b is formed of a material having a higher density than the spring portion 4a, the mass portion 4b has a larger mass than the spring portion 4a, and a spring mass resonator can be constituted. When the spring portion 4a is a frustum of a cone shape that tapers in a direction away from the film portion 2 as in the modification shown in FIGS. 5A and 5B, the mold release property from the mold is good when the film portion 2 and the spring portion 4a are integrally molded.

[0037] In this embodiment, the spring portion 4a and the mass portion 4b of the weight portion 4 are made to have different materials and / or volumes, so that the mass of the mass portion 4b is made larger than that of the spring portion 4a to form a spring-mass resonator, and a sufficient sound insulation effect is obtained. That is, the materials, shapes, and dimensions of the spring portion 4a and the mass portion 4b are determined so that a spring-mass resonator capable of exhibiting a sufficient sound insulation effect can be formed. As long as the mass of the mass portion 4b can be made larger than that of the spring portion 4a to such an extent that a spring-mass resonator capable of exhibiting a sufficient sound insulation effect is formed, the materials, shapes, and dimensions of the spring portion 4a and the mass portion 4b can be freely selected. However, since the spring portion 4a functions as a spring, it needs to be formed from a flexible material.

[0038] [Second Embodiment] FIG. 6A is a perspective view of the sound insulation structure 6 according to the second embodiment of the present invention, and FIG. 6B is a cross-sectional view taken along the line A-A of FIG. 6A and turned upside down. The sound insulation structure 6 has a weight portion 7 having a single structure that is not divided into a spring portion and a mass portion. In this embodiment, a spring-mass resonator is formed in which the entire weight portion 7 functions as a mass portion and the film portion 2 functions as a spring portion. As an example, the mass of the weight portion 7 is about 0.1 g to 2.0 g. The material of the weight portion 7 is not limited, and it is formed of, for example, a synthetic resin or metal. Since the other configurations are the same as those of the first embodiment described above, the description thereof is omitted. Also in the sound insulation structure 6 of this embodiment, the membrane vibration is controlled by the action of the spring-mass resonator constituted by the weight portion 7 and the membrane portion 2, and in a specific frequency range (for example, 1000 Hz or less), the membrane vibration is significantly reduced and high sound insulation performance is exhibited. Note that the air in the space surrounded by the membrane portion 2 and the support wall portion 3 together with the membrane portion 2 may function as a part of the spring (air spring) of the spring-mass resonator.

[0039] In this embodiment, both the film portion 2 and the support wall portion 3 preferably have a dynamic storage modulus (E') of 0.01 MPa or more and 100 MPa or less at a frequency of 1 Hz to 1000 Hz at 23°C, and preferably have a loss tangent (tanδ) of 0.01 or more and 0.50 or less at a frequency of 1 Hz to 1000 Hz at 23°C. Further, both the film portion 2 and the support wall portion 3 in this embodiment preferably have a dynamic storage modulus (E') of 0.05 MPa or more and 50 MPa or less at a frequency of 1 Hz to 1000 Hz at 23°C, and a loss tangent (tanδ) of 0.05 or more and 0.50 or less at a frequency of 1 Hz to 1000 Hz at 23°C.

[0040] In addition, the support wall portion 3 of this embodiment is made of any one of a material having no energy elasticity but having rubber elasticity, a material having no rubber elasticity but having energy elasticity, and a material having both rubber elasticity and energy elasticity. Similarly, the film portion 2 of this embodiment is also made of any one of a material having no energy elasticity but having rubber elasticity, a material having no rubber elasticity but having energy elasticity, and a material having both rubber elasticity and energy elasticity.

[0041] FIG. 7A is a cross-sectional view of the sound insulation structure 6 of a modified example of the second embodiment of the present invention, and FIG. 7B is a perspective view of the weight portion 7 of the sound insulation structure 6. In this modified example, the weight portion 7 has a frustum of a cone shape that tapers in a direction away from the film portion 2. With this configuration, the mold release property from the mold when the film portion 2 and the weight portion 7 are integrally molded is good. In this embodiment, the shape of the weight portion 7 can be arbitrarily determined and is not particularly limited.

[0042] In any of the first and second embodiments, the film portion 2 and the support wall portion 3 can be formed by integral molding or two-color molding such as injection molding, compression molding, press molding, extrusion molding, transfer molding, casting, etc. of the materials described above. Further, the weight portions 4 and 7 may also be formed together with the film portion 2 and the support wall portion 3 by integral molding, two-color molding, insert molding, etc. of the materials described above. However, the sound insulation structures 1 and 6 may be assembled by separately forming the film portion 2, the support wall portion 3, and the weight portions 4 and 7 and then joining them to each other by adhesion or heat fusion.

[0043] In the configurations of the sound insulation structures 1 and 6 described above, as shown in FIGS. 8A and 8B, the support wall portion 3 includes a plurality of first wall portions 3a extending in a first direction D1 parallel to the film portion 2 and a plurality of second wall portions 3b extending in a second direction D2 orthogonal to the first direction D1, and the planar shape of each partition 5 is a square. In other words, the support wall portion 3 is a square tube shape having a square cross-sectional shape that defines each partition 5, and a large number of square tube-shaped support wall portions 3 are arranged side by side, and the support wall portions 3 of adjacent partitions 5 are integrated. However, the present invention is not limited to such a configuration. For example, as shown in FIGS. 9A and 9B, the planar shape of each partition 5 may be a triangle, and the support wall portion 3 may be a square tube shape having a triangular cross-sectional shape that defines each partition 5. Further, as shown in FIGS. 10A and 10B, the planar shape of each partition 5 may be a pentagon, and the support wall portion 3 may be a square tube shape having a pentagonal cross-sectional shape that defines each partition 5. As shown in FIGS. 11A and 11B, the planar shape of each partition 5 may be a hexagon, and the support wall portion 3 may be a square tube shape having a hexagonal cross-sectional shape that defines each partition 5, constituting a so-called honeycomb structure. Furthermore, as shown in FIGS. 12A and 12B, the planar shape of each partition 5 may be a circle, and the support wall portion 3 may be a cylindrical shape having a circular cross-sectional shape that defines each partition 5. In the case of the configurations shown in FIGS. 10A, 10B, 12A, and 12B, since a gap is generated between the partitions 5, it is preferable to determine the shape and dimensions of the support wall portion 3 so that the gap becomes small. In the case of the configurations shown in FIGS. 8A, 8B, 9A, 9B, 11A, and 11B, no gap is generated between the partitions 5. Further, each partition 5 may have various shapes not shown, for example, a rectangle, a parallelogram, a trapezoid, a polygon having seven or more sides, an ellipse, an oblong, etc., or an irregular shape. The support wall portion 3 is formed in a shape and dimensions corresponding to the planar shape of each partition 5.

[0044] The sound insulation structures 1 and 6 of the present invention are very thin and lightweight, and are also easy to place on surfaces with curved surfaces or unevenness. Therefore, they may be placed and used on panels of vehicles, particularly automobiles. Panels of automobiles and the like are basically airtight plates. As an example, metal plates (iron plates, steel plates, aluminum plates), resin plates, etc. can be mentioned. When the panel on which the sound insulation structure 1 is placed is a metal plate, its thickness is preferably in the range of 0.5 mm to 2.0 mm. When it is a resin plate, its thickness is preferably in the range of 0.5 mm to 20 mm. When the sound insulation structures 1 and 6 are placed on the panel of an automobile, it is preferable that the end surface of the support wall portion 3 of the sound insulation structures 1 and 6 on the side opposite to the side attached to the film portion 2 is placed on the panel. Also, in this case, the support wall portion 3 and the panel may or may not be adhered, but it is preferable that the support wall portion 3 is placed and used on the panel without being adhered to the panel.

[0045] Further, the sound insulation structures 1 and 6 of the present invention may be used alone, or may be used in combination with other members (not shown). When the sound insulation structures 1 and 6 of the present invention are used in combination with other members, they may be laminated or joined with the other members. When laminated or joined with other members, the sound insulation structures 1 and 6 may be placed so as to be in contact with the portion (for example, the panel of an automobile) on which the sound insulation structures 1 and 6 are placed, or may be placed so that other members are in contact with that portion. The other members used in combination with the sound insulation structures 1 and 6 may be made of various materials.

[0046] As for the parts where the sound insulation structures 1 and 6 of the present invention are installed in an automobile, in the engine compartment, examples include an engine head cover, an engine body cover, a hood insulator, a dash front insulator, the wall of an air box, a cleaner of an air intake, a dust side duct, an under cover, etc.; in the cabin, examples include a dash insulator, a dash panel, a floor carpet (floor silencer), a spacer, a door trim of a door, the inside of the door trim, an instrument panel, an instrument center box, an instrument upper box, a housing of an air conditioner, a roof trim, the inside of the roof trim, a sun visor, a rear seat air conditioner duct, a cooling duct of a battery cooling system in a vehicle equipped with a battery, a cooling fan, a trim of a center console, the inside of the console, a parcel trim, a parcel panel, a headrest of a seat, a seat back of a front seat, a seat back of a rear seat, etc.; in the trunk, examples include a trim of a trunk side, the inside of the trim, a drafter cover, etc. Further, the sound insulation structures 1 and 6 of the present invention can also be installed inside the skeleton of an automobile or between panels, and furthermore, can also be installed in an under cover under the floor located outside the vehicle, a fender protector, a back door, a wheel cover, an aerodynamic cover of a suspension, etc.

[0047] Specific examples and comparative examples of the sound insulation structure of the present invention will be described below. [Example 1] The sound insulation structure 1 of Example 1 of the present invention has the same structure as the first embodiment shown in FIGS. 1A to 2B. The film portion 2 is made of an elastic body having a dynamic storage modulus (E') of 0.01 MPa or more and 100 MPa or less at a frequency of 1 Hz to 1000 Hz at 23°C and a loss tangent (tanδ) of 0.01 or more and 0.50 or less at a frequency of 1 Hz to 1000 Hz at 23°C. More specifically, the film portion 2 of this example has a dynamic storage modulus (E') of 20.4 MPa and a loss tangent (tanδ) of 0.12 at a frequency of 1 Hz at 23°C, a dynamic storage modulus (E') of 23.0 MPa and a loss tangent (tanδ) of 0.13 at a frequency of 10 Hz at 23°C, a dynamic storage modulus (E') of 25.4 MPa and a loss tangent (tanδ) of 0.16 at a frequency of 100 Hz at 23°C, a dynamic storage modulus (E') of 28.8 MPa and a loss tangent (tanδ) of 0.14 at a frequency of 1000 Hz at 23°C, a durometer A hardness of 70 according to JIS K6253, and is made of EPDM (ethylene-propylene-diene rubber) with a film thickness of 0.5 mm. When the planar shape of this film portion 2 is a square with an area of 1000 cm 2 the bending rigidity K is 67.2 N / mm 2 and when the planar shape is a square with an area of 400 cm 2 the bending rigidity K is 42.5 N / mm 2 . If a film portion made of the same material as this film portion 2 with a film thickness of 3 mm and a planar shape of a square with an area of 1000 cm 2 is formed, its bending rigidity K is about 1.5×10 4 N / mm 2 .

[0048] The support wall portion 3 of this embodiment is made of an elastic body having a dynamic storage modulus (E') of 0.01 MPa or more and 100 MPa or less at a frequency of 1 Hz to 1000 Hz at 23°C and a loss tangent (tanδ) of 0.01 or more and 0.50 or less at a frequency of 1 Hz to 1000 Hz at 23°C. More specifically, the support wall portion 3 of this embodiment has a dynamic storage modulus (E') of 13.2 MPa and a loss tangent (tanδ) of 0.12 at a frequency of 1 Hz at 23°C, a dynamic storage modulus (E') of 15.0 MPa and a loss tangent (tanδ) of 0.14 at a frequency of 10 Hz at 23°C, a dynamic storage modulus (E') of 17.4 MPa and a loss tangent (tanδ) of 0.17 at a frequency of 100 Hz at 23°C, a dynamic storage modulus (E') of 20.2 MPa and a loss tangent (tanδ) of 0.16 at a frequency of 1000 Hz at 23°C, a durometer A hardness of 65 according to JIS K6253, a plate thickness of 1.6 mm, and is made of EPDM with a height in the direction orthogonal to the film portion 2 of 10 mm. However, only the outermost support wall portion 3 has a plate thickness of 0.8 mm, which is half. The compartment 5 defined by the plurality of support wall portions 3 (the first wall portion 3a and the second wall portion 3b) is square in shape with a size of 25 mm × 25 mm, and there are 49 compartments 5 in the 200 mm × 200 mm square region (evaluation surface) of the film portion 2. However, only a part of this region is schematically shown in the drawing. The weight portion 4 is cylindrical with a diameter of 6 mm and a height (dimension in the direction orthogonal to the film portion 2) of 6 mm.

[0049] Among the weight portions 4, the spring portion 4a, which is the portion on the side attached to the film portion 2, has a height of 3 mm, a dynamic storage modulus (E') of 0.01 MPa or more and 100 MPa or less at a frequency of 1 Hz to 1000 Hz at 23°C, and a loss tangent (tanδ) of 0.01 or more and 0.50 or less at a frequency of 1 Hz to 1000 Hz at 23°C. It is made of an elastic body within this range. More specifically, the spring portion 4a of this embodiment has a dynamic storage modulus (E') of 0.60 MPa and a loss tangent (tanδ) of 0.17 at a frequency of 1 Hz at 23°C, a dynamic storage modulus (E') of 0.74 MPa and a loss tangent (tanδ) of 0.24 at a frequency of 10 Hz at 23°C, a dynamic storage modulus (E') of 0.97 MPa and a loss tangent (tanδ) of 0.17 at a frequency of 100 Hz at 23°C, a dynamic storage modulus (E') of 1.31 MPa and a loss tangent (tanδ) of 0.16 at a frequency of 1000 Hz at 23°C, and is made of a silicone rubber with a durometer A hardness of 10 according to JIS K6253. The mass portion 4b, which is the portion of the weight portion 4 on the side opposite to the side attached to the film portion 2, also has a height of 3 mm and is made of rigid stainless steel (SUS304). The mass of the weight portion 4 is approximately 0.8 g, and it has a resonance with a peak at a frequency of 600 Hz to 650 Hz with respect to the direction perpendicular to the installation surface of the weight portion 4. The overall height of the sound insulation structure 1 is 10.5 mm, and the total areal density including the film portion 2, the support wall portion 3, and the weight portion 4 in one compartment 5 is 2.97 kg / m 2 is.

[0050] As shown in Fig. 13, the end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 was placed on an iron plate 8 with a thickness of 0.8 mm, and the sound insulation property was measured with the surface of the iron plate 8 on the side opposite to the side on which the sound insulation structure 1 was placed as the incident sound side. Specifically, in accordance with the intensity method shown in JIS A1441-1, a test facility room in which the sound source room is a reverberation room and the receiving room is a semi-anechoic room was used, and the acoustic transmission loss (transmission loss) [dB] with respect to the 1 / 3 octave band center frequency [Hz] by 1 / 3 octave band analysis was obtained. The relationship between the 1 / 3 octave band center frequency and the acoustic transmission loss is shown in Figs. 14A to 14F and 14K. The higher the acoustic transmission loss, the higher the sound insulation property. Note that at the 1 / 3 octave band center frequency [Hz] shown in Figs. 14A to 14K, 1 kHz is 1000 Hz, and the prefix "k" means 1000.

[0051] [Comparative Example 1] As Comparative Example 1, as shown in Fig. 15, the sound insulation property was measured in a state where nothing was placed on the iron plate 8 with a thickness of 0.8 mm, and the relationship between the 1 / 3 octave band center frequency and the acoustic transmission loss is shown in Fig. 14A. This shows a state where the sound insulation structure is not provided. The surface density of this configuration is 6.02 kg / m 2 is.

[0052] [Comparative Example 2] As Comparative Example 2, the theoretical value of the sound insulation property calculated based on the mass law when a member having the same mass as the sound insulation structure 1 of Example 1 was placed on the iron plate 8 with a thickness of 0.8 mm was obtained, and the relationship between the 1 / 3 octave band center frequency and the acoustic transmission loss is shown in Fig. 14A. The surface density of this configuration is 8.99 kg / m 2 is.

[0053] [Comparative Example 3] As Comparative Example 3, as shown in FIGS. 16A and 16B, a sound insulation structure composed only of the film portion 2 and the support wall portion 3 was placed on an iron plate 8 with a thickness of 0.8 mm, and the sound insulation performance was measured. The relationship between the 1 / 3 octave band center frequency and the acoustic transmission loss is shown in FIGS. 14A to 14B. The film portion 2 and the support wall portion 3 of this comparative example are the same as the film portion 2 and the support wall portion 3 of Example 1, but the weight portion 4 does not exist. The areal density of this configuration is 2.43 kg / m 2 is.

[0054] [Example 2] The sound insulation structure 6 of Example 2 of the present invention has the same structure as the second embodiment shown in FIGS. 6A and 6B. The film portion 2 and the support wall portion 3 of this example are the same as the film portion 2 and the support wall portion 3 of Example 1. The weight portion 7 is made of EPDM with a durometer A hardness of 65 according to JIS K6253-3, and is cylindrical with a diameter of 13 mm and a height (dimension in the direction orthogonal to the film portion 2) of 5 mm. The mass of the weight portion 7 is about 0.85 g, and the areal density of this configuration is 3.04 kg / m 2 is. As shown in FIG. 17, the end face of the support wall portion 3 of the sound insulation structure 6 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to obtain the sound insulation performance, which is shown in FIG. 14B.

[0055] [Example 3] The sound insulation structure 6 of Example 3 of the present invention shown in FIGS. 18A and 18B has the same structure as Example 2, but has a weight portion 7 smaller than the weight portion 7 of Example 2. The film portion 2 and the support wall portion 3 of this example are the same as the film portion 2 and the support wall portion 3 of Example 1. The weight portion 7 is made of EPDM with a durometer A hardness of 65 according to JIS K6253-3, and is cylindrical with a diameter of 6 mm and a height (dimension in the direction orthogonal to the film portion 2) of 5 mm. The mass of the weight portion 7 is about 0.15 g. The areal density of this configuration is 2.54 kg / m 2 is. As shown in FIG. 18B, the end face of the support wall portion 3 of the sound insulation structure 6 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to obtain the sound insulation performance, which is shown in FIG. 14B.

[0056] [Example 4] The sound insulation structure 1 (not shown) of Example 4 of the present invention has the same structure as that of Example 1, but has a support wall portion 3 that is softer than the support wall portion 3 of Example 1. The film portion 2 and the weight portion 4 of this example are the same as the film portion 2 and the weight portion 4 of Example 1. The support wall portion 3 of this example is made of an elastic body having a dynamic storage modulus (E') of 0.01 MPa or more and 100 MPa or less at a frequency of 1 Hz to 1000 Hz at 23°C and a loss tangent (tanδ) of 0.01 or more and 0.50 or less at a frequency of 1 Hz to 1000 Hz at 23°C. More specifically, the support wall portion 3 of this example has a dynamic storage modulus (E') of 1.48 MPa and a loss tangent (tanδ) of 0.07 at a frequency of 1 Hz at 23°C, a dynamic storage modulus (E') of 1.72 MPa and a loss tangent (tanδ) of 0.12 at a frequency of 10 Hz at 23°C, a dynamic storage modulus (E') of 2.00 MPa and a loss tangent (tanδ) of 0.11 at a frequency of 100 Hz at 23°C, a dynamic storage modulus (E') of 2.33 MPa and a loss tangent (tanδ) of 0.12 at a frequency of 1000 Hz at 23°C, a durometer A hardness of 30 according to JIS K6253-3, a plate thickness of 1.6 mm, and is made of EPDM with a height of 10 mm in the direction orthogonal to the film portion 2. However, only the outermost support wall portion 3 has a plate thickness of 0.8 mm, which is half. The surface density of this configuration is 2.52 kg / m 2 2 is. The sound insulation property is obtained by placing the end face of the support wall portion 3 of the sound insulation structure 1 on the iron plate 8 with a thickness of 0.8 mm on the side opposite to the side attached to the film portion 2, and is shown in FIG. 14C.

[0057] [Comparative Example 4] The sound insulation structure of Comparative Example 4 (not shown) has substantially the same structure as that of Example 1, but has a support wall portion 3 that is harder and less flexible than the support wall portion 3 of Example 1. The film portion 2 and the weight portion 4 of this comparative example are the same as those of the film portion 2 and the weight portion 4 of Example 1. The support wall portion 3 of this comparative example is made of polylactic acid (PLA resin) with a dynamic storage modulus (E') of 2.03 GPa and a loss tangent (tanδ) of 0.0045 at a frequency of 1 Hz at 23°C, a dynamic storage modulus (E') of 2.04 GPa and a loss tangent (tanδ) of 0.000060 at a frequency of 10 Hz at 23°C, a dynamic storage modulus (E') of 2.05 GPa and a loss tangent (tanδ) of 0.045 at a frequency of 100 Hz at 23°C, and a dynamic storage modulus (E') of 2.07 GPa and a loss tangent (tanδ) of 0.0079 at a frequency of 1000 Hz at 23°C, and its shape and dimensions are the same as those of the support wall portion 3 of Example 1. The areal density of this configuration is 2.63 kg / m 2 is. The sound insulation performance was determined by placing the end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 on an iron plate 8 with a thickness of 0.8 mm, and is shown in Fig. 14C.

[0058] [Example 5] The sound insulation structure 1 of Example 5 (not shown) has the same structure as that of Example 1, but has a film portion 2 that is softer than the film portion 2 of Example 1. The support wall portion 3 and the weight portion 4 of this example are the same as those of the support wall portion 3 and the weight portion 4 of Example 1. The film portion 2 of this example is made of EPDM with a durometer A hardness of 30 according to JIS K6253-3, which is the same material as the support wall portion 3 of Example 4, and its shape and dimensions are the same as those of the film portion 2 of Example 1. The areal density of this configuration is 2.83 kg / m 2 is. The sound insulation performance was determined by placing the end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 on an iron plate 8 with a thickness of 0.8 mm, and is shown in Fig. 14D.

[0059] [Example 6] The sound insulation structure 1 of Example 6 shown in FIGS. 19A and 19B has the same structure as that of Example 1, but has a partition 5 that is wider than the partition 5 of Example 1. The film portion 2 and the weight portion 4 of this example are the same as the film portion 2 and the weight portion 4 of Example 1. And the support wall portion 3 itself of this example is the same as the support wall portion 3 of Example 1, but is arranged side by side at a wider interval than in Example 1. As a result, each partition of this example has a square shape of 50 mm × 50 mm, and its area is 2500 mm 2 2. This surface density of this configuration is 1.60 kg / m 2 2. There are 9 partitions 5 in the 200 mm × 200 mm square region (evaluation surface) of the film portion 2. However, only a part of this region is schematically shown in the drawing. As shown in FIG. 19B, the sound insulation performance is obtained by placing the end face of the support wall portion 3 of the sound insulation structure on the side opposite to the side attached to the film portion 2 on an iron plate 8 with a thickness of 0.8 mm, as shown in FIG. 14E.

[0060] [Example 7] The sound insulation structure 1 (not shown) of Example 7 has the same structure as that of Example 1, but the weight portion 4 is cylindrical with a diameter of 13 mm and a height (dimension in the direction orthogonal to the film portion 2) of 9 mm. Among this weight portion 4, the spring portion 4a, which is the portion on the side attached to the film portion 2, has a height of 4 mm, a dynamic storage modulus (E') at 23°C in the frequency range of 1 Hz to 1000 Hz of 0.01 MPa or more and 100 MPa or less, and a loss tangent (tanδ) at 23°C in the frequency range of 1 Hz to 1000 Hz of 0.01 or more and 0.50 or less, and is made of an elastic body. More specifically, the spring portion 4a of this example has a dynamic storage modulus (E') of 0.06 MPa and a loss tangent (tanδ) of 0.15 at 1 Hz and 23°C, a dynamic storage modulus (E') of 0.07 MPa and a loss tangent (tanδ) of 0.15 at 10 Hz and 23°C, a dynamic storage modulus (E') of 0.08 MPa and a loss tangent (tanδ) of 0.15 at 100 Hz and 23°C, and a dynamic storage modulus (E') of 0.10 MPa and a loss tangent (tanδ) of 0.15 at 1000 Hz and 23°C, and is made of polyurethane foam. The mass portion 4b, which is the portion of the weight portion 4 on the side opposite to the side attached to the film portion 2, has a height of 5 mm and is made of EPDM with a durometer A hardness of 65 according to JIS K6253-3. The mass of the weight portion 4 is approximately 1.0 g.

[0061] The film portion 2 and the support wall portion 3 of this example are the same as the film portion 2 and the support wall portion 3 of Example 1. The areal density of this configuration is 3.08 kg / m 2 ². The end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to determine the sound insulation performance, as shown in FIG. 14F.

[0062] [Example 8] The sound insulation structure 1 (not shown) of Example 8 has the same structure as the modified example of the first embodiment shown in FIGS. 3A and 3B. The film portion 2 and the support wall portion 3 of this example are the same as those of the film portion 2 and the support wall portion 3 of Example 1. However, the weight portion 4 of this example is composed of a small-diameter cylindrical spring portion 4a and a large-diameter cylindrical mass portion 4b. The spring portion 4a, which is the portion of the weight portion 4 attached to the film portion 2, is cylindrical with a diameter of 6 mm and a height (dimension in the direction perpendicular to the film portion 2) of 3 mm, and is made of the same material as the spring portion 4a of the weight portion 4 in Example 1 (silicone rubber with a durometer A hardness of 10 according to JIS K6253-3). The mass portion 4b, which is the portion of the weight portion 4 on the side opposite to the side attached to the film portion 2, is cylindrical with a diameter of 13 mm and a height of 5 mm, and is made of EPDM with a durometer A hardness of 65 according to JIS K6253-3. The mass of the weight portion 4 is approximately 1.0 g. The areal density of this configuration is 3.13 kg / m 2 2. The end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to obtain the sound insulation performance, which is shown in FIGS. 14F to 14G.

[0063] [Example 9] The sound insulation structure 1 (not shown) of Example 9 has the same structure as the modified example of the first embodiment shown in FIGS. 3A and 3B. The film portion 2 and the weight portion 4 of this example are the same as those of the film portion 2 and the weight portion 4 of Example 8. However, the support wall portion 3 of this example is made of EPDM with a durometer A hardness of 30 according to JIS K6253, a plate thickness of 1.6 mm, and a height in the direction perpendicular to the film portion 2 of 10 mm. The areal density of this configuration is 2.81 kg / m 2 2. The end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to obtain the sound insulation performance, which is shown in FIGS. 14G to 14I.

[0064] [Example 10] The sound insulation structure 1 of Example 10 shown in FIG. 20 has the same structure as the modified example of the first embodiment shown in FIGS. 3A and 3B. The film portion 2 and the weight portion 4 of this example are the same as those of the film portion 2 and the weight portion 4 of Example 9, but the support wall portion 3 of this example is made of EPDM with a durometer A hardness of 30 according to JIS K6253, a plate thickness of 1.6 mm, and a height in the direction orthogonal to the film portion 2 of 14 mm. The areal density of this configuration is 3.16 kg / m 2 is. The end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to obtain sound insulation performance, as shown in FIG. 14H.

[0065] [Example 11] The sound insulation structure 1 of Example 11 shown in FIGS. 21A and 21B has the same structure as the modified example of the first embodiment shown in FIGS. 3A and 3B. FIG. 21A is a perspective view of the sound insulation structure 1, and FIG. 21B is a cross-sectional view taken along the line B-B thereof. The film portion 2 and the weight portion 4 of this example are the same as those of the film portion 2 and the weight portion 4 of Example 9, but in this example, among a plurality of support wall portions, some support wall portions 3d extend in the direction orthogonal to the film portion 2 with a higher height than the other support wall portions 3c. That is, the sound insulation structure 1 of this example has a support wall portion (some support wall portions) 3d with a high height similar to the support wall portion 3 of Embodiment 10, and a support wall portion (other support wall portions) 3c with a low height similar to the support wall portion 3 of Example 9. Specifically, the support wall portion 3c is made of EPDM with a durometer A hardness of 30 according to JIS K6253, a plate thickness of 1.6 mm, and a height in the direction orthogonal to the film portion 2 of 10 mm, and the support wall portion 3d is made of EPDM with a durometer A hardness of 30 according to JIS K6253, a plate thickness of 1.6 mm, and a height in the direction orthogonal to the film portion 2 of 15 mm. The support wall portion 3d has a height 1.5 times that of the support wall portion 3c. In this example, as shown in FIGS. 21A and 21B, the rows in which the support wall portions 3d with a high height are arranged and the rows in which only the support wall portions 3c with a low height are arranged are alternately positioned. Thereby, out of 49 square sections 5 arranged in a 7×7 grid, 16 sections 5 are sections surrounded by the support wall portions 3d with a high height. The areal density of this configuration is 3.02 kg / m 2It is. The end face of the support wall portion 3d of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to obtain sound insulation performance, as shown in FIG. 14I.

[0066] [Example 12] The sound insulation structure 1 (not shown) of Example 12 has the same structure as a modification of the first embodiment shown in FIGS. 3A and 3B. The weight portion 4 of this example is the same as the weight portion 4 of Example 8. The film portion 2 and the support wall portion 3 of this example have a dynamic storage modulus (E') of 7.81 MPa and a loss tangent (tanδ) of 0.06 at a frequency of 1 Hz at 23°C, a dynamic storage modulus (E') of 8.62 MPa and a loss tangent (tanδ) of 0.08 at a frequency of 10 Hz at 23°C, a dynamic storage modulus (E') of 9.19 MPa and a loss tangent (tanδ) of 0.11 at a frequency of 100 Hz at 23°C, a dynamic storage modulus (E') of 10.3 MPa and a loss tangent (tanδ) of 0.08 at a frequency of 1000 Hz at 23°C, a durometer A hardness according to JIS K6253 of 50, a thickness of the film portion 2 of 1.0 mm, a plate thickness of the support wall portion 3 of 1.2 mm, and a height in the direction orthogonal to the film portion 2 of 10 mm, and is formed by integral molding of a styrene-based thermoplastic elastomer (TPS). The areal density of this configuration is 2.56 kg / m 2 It is. The end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to obtain sound insulation performance, as shown in FIG. 14J.

[0067] [Example 13] The sound insulation structure 1 (not shown) of Example 13 has the same structure as the modified example of the first embodiment shown in FIGS. 3A and 3B. The film portion 2 and the support wall portion 3 of this example are the same as the film portion 2 and the support wall portion 3 of Example 12. The weight portion 4 of this example is composed of a small-diameter cylindrical spring portion 4a and a large-diameter cylindrical mass portion 4b. The spring portion 4a, which is the portion of the weight portion 4 on the side attached to the film portion 2, is cylindrical with a diameter of 6 mm and a height (dimension in the direction perpendicular to the film portion 2) of 3 mm. At 23°C, the dynamic storage modulus (E') at a frequency of 1 Hz is 0.19 MPa, the loss tangent (tanδ) is 0.03, the dynamic storage modulus (E') at a frequency of 10 Hz is 0.19 MPa, the loss tangent (tanδ) is 0.04, the dynamic storage modulus (E') at a frequency of 100 Hz is 0.19 MPa, the loss tangent (tanδ) is 0.25, the dynamic storage modulus (E') at a frequency of 1000 Hz is 0.23 MPa, and the loss tangent (tanδ) is 0.04. It is made of TPS with a durometer A hardness of 0 according to JIS K6253. The mass portion 4b, which is the portion of the weight portion 4 on the side opposite to the side attached to the film portion 2, is cylindrical with a diameter of 11 mm and a height of 6 mm and is made of EPDM with a durometer A hardness of 70 according to JIS K6253-3. The areal density of this configuration is 2.50 kg / m 2 ². The end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to obtain the sound insulation performance, as shown in FIG. 14J.

[0068] [Example 14] The sound insulation structure 1 (not shown) of Example 13 has the same structure as the modified example of the first embodiment shown in FIGS. 3A and 3B. The film portion 2 and the support wall portion 3 of this example are the same as the film portion 2 and the support wall portion 3 of Example 12. The weight portion 4 of this example is composed of a small-diameter cylindrical spring portion 4a and a large-diameter cylindrical mass portion 4b. The spring portion 4a, which is the portion of the weight portion 4 attached to the film portion 2, is cylindrical with a diameter of 6 mm and a height (dimension in the direction perpendicular to the film portion 2) of 3 mm. The mass portion 4b, which is the portion of the weight portion 4 opposite to the side attached to the film portion 2, is cylindrical with a diameter of 9 mm and a height of 6 mm. The spring portion 4a and the mass portion 4b of the weight portion 4 of this example have a dynamic storage modulus (E') of 0.21 MPa and a loss tangent (tanδ) of 0.04 at a frequency of 1 Hz at 23°C, a dynamic storage modulus (E') of 0.23 MPa and a loss tangent (tanδ) of 0.03 at a frequency of 10 Hz at 23°C, a dynamic storage modulus (E') of 0.29 MPa and a loss tangent (tanδ) of 0.05 at a frequency of 100 Hz at 23°C, a dynamic storage modulus (E') of 0.25 MPa and a loss tangent (tanδ) of 0.17 at a frequency of 1000 Hz at 23°C, and are made of TPS with a durometer A hardness of 5 according to JIS K6253. The areal density of this configuration is 2.50 kg / m 2 ². The end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm, and the sound insulation performance is obtained and shown in FIG. 14J.

[0069] [Comparative Example 5] As Comparative Example 5, similar to Comparative Example 3, as shown in FIGS. 16A and 16B, a sound insulation structure composed only of the film portion 2 and the support wall portion 3 is placed on an iron plate 8 with a thickness of 0.8 mm, and the sound insulation performance is measured. The relationship between the 1 / 3 octave band center frequency and the acoustic transmission loss is shown in FIG. 14J. The film portion 2 and the support wall portion 3 of this comparative example are the same as the film portion 2 and the support wall portion 3 of Example 12, different from the film portion 2 and the support wall portion 3 of Example 1 and Comparative Example 3. And there is no weight portion 4 in the sound insulation structure of this comparative example. The areal density of this configuration is 1.88 kg / m 2 ².

[0070] [Comparative Example 6] The sound insulation structure 1 (not shown) of Comparative Example 6 has the same structure as that of Example 1, but has a film portion 2 made of a resin material with a thickness thinner than that of the film portion 2 of Example 1. The support wall portion 3 and the weight portion 4 of this comparative example are the same as those of the support wall portion 3 and the weight portion 4 of Example 1. The film portion 2 of this comparative example is made of low-density polyethylene (LDPE) with a thickness of 0.05 mm. The areal density of this configuration is 2.25 kg / m 2 is. The end face of the support wall portion 3 of the sound insulation structure 1 on the side opposite to the side attached to the film portion 2 is placed on an iron plate 8 with a thickness of 0.8 mm to obtain the sound insulation performance, which is shown in FIG. 14K.

[0071] [Results] The results of comparing Examples 1 to 14 and Comparative Examples 1 to 6 of the present invention described above will be explained. Referring to FIG. 14A, it can be seen that the sound insulation effect is improved by the sound insulation structure 1 of the present invention. In particular, according to the sound insulation structure 1 of Example 1, in a frequency band higher than 630 Hz, a significantly greater sound insulation effect than the theoretical value (Comparative Example 2) based on the mass law is obtained, indicating that the effect of the present invention is significant. And in particular, when compared with Comparative Example 3 in a frequency band lower than 1.25 kHz, it can be seen that the sound insulation performance of Example 1 having the weight portion 4 is high.

[0072] Referring to FIG. 14B, it can be seen that a similarly good sound insulation effect is obtained in the sound insulation structure 1 (Example 1) of the first embodiment and the sound insulation structure 6 (Examples 2 and 3) of the second embodiment of the present invention. When the weight portion 4 itself constitutes a spring-mass resonator as in Example 1, particularly good sound insulation is obtained in the vicinity of the frequency (for example, 630 Hz to 1000 Hz) at which the vibration of the film portion 2 is reduced by the resonance of the spring-mass resonator. On the other hand, when the spring-mass resonator is constituted by the weight portion 7 and the film portion 2 as in Examples 2 and 3, the frequency band with particularly good sound insulation can be adjusted by the weight of the weight portion 7. For example, when the weight portion 7 has the same mass as the weight portion 4 of Example 1, the frequency band with particularly good sound insulation is around 1000 Hz, and when the weight portion 7 is made lighter, the frequency band with particularly good sound insulation can be shifted to the high-frequency side.

[0073] Referring to Fig. 14C, it can be seen that if the support wall portion 3 of the sound insulation structure is not made of a flexible material, the sound insulation performance is low, but if the support wall portion 3 is made of a flexible material, a good sound insulation effect can be obtained. This is because when the support wall portion 3 is not made of a flexible material but a hard material, vibration is likely to propagate to the film portion 2 through the support wall portion 3, while when the support wall portion 3 is made of a flexible material, vibration is less likely to propagate to the film portion 2 through the support wall portion 3. In addition, depending on the hardness of the support wall portion 3, the frequency band with particularly good sound insulation can be adjusted. For example, if the support wall portion 3 is made softer, the frequency band with particularly good sound insulation can be shifted to the low-frequency side.

[0074] Referring to Fig. 14D, it can be seen that if the film portion 2 of the sound insulation structure is too soft, the sound insulation performance will decrease slightly. This is considered to be because if the film portion 2 is too soft, the vibration to the extent that the spring mass resonator functions sufficiently will not be transmitted to the spring mass resonator.

[0075] Referring to Fig. 14E, it can be seen that if each section 5 of the film portion 2 defined by the support wall portion 3 of the sound insulation structure is too large, the sound insulation performance will decrease slightly. This is because if each section 5 is too large, the spring mass resonator will not function sufficiently and the vibration reduction effect will be weakened. Therefore, it is preferable that each section 5 is small to a certain extent (for example, 1000 mm 2 or less).

[0076] Referring to Fig. 14F, it is shown that even if the materials and shapes of the weight portions 4 of the sound insulation structure 1 are different, as long as each is within the preferable range of materials and shapes, the sound insulation function in the present invention is exhibited. Therefore, it can be understood that the materials and shapes of the weight portions 4 and the like can be freely set within the preferable range.

[0077] Referring to Fig. 14G, it can be seen that even if the durometer A hardness of the support wall portion 3 according to JIS K6253-3 is somewhat different, a similar sound insulation effect can be obtained. And referring to Fig. 14H, it can be seen that a good sound insulation effect can be obtained by a configuration in which the height of the support wall portion 3 extending in the direction orthogonal to the film portion 2 is high. This is because when the height of the support wall portion 3 is high, the thickness of the air layer located between the mounting surface (the iron plate 8 in each embodiment) on which the sound insulation structures 1 and 6 are mounted and the film portion 2 is large, so the frequency band of the resonance transmission of air changes, and the influence of the sound insulation inhibition in the target frequency band is reduced, and particularly the sound insulation volume in the low frequency band (for example, around 500 Hz) becomes large.

[0078] Referring to Fig. 14I, it can be seen that even in a configuration in which only some of the support wall portions 3d of the plurality of support wall portions have a high height extending in the direction orthogonal to the film portion 2 and the height of the other support wall portions 3c is low, a good sound insulation effect can be obtained. Even in a configuration in which only some of the support wall portions 3d have a high height, the thickness of the air layer located between the mounting surface (the iron plate 8 in each embodiment) on which the sound insulation structures 1 and 6 are mounted and the film portion 2 becomes large as in the configuration in which all of the support wall portions 3d have a high height. Therefore, as described above, particularly the sound insulation volume in the low frequency band (for example, around 500 Hz) becomes large. And by increasing the height of only some of the support wall portions 3d, while increasing the thickness of the air layer, an increase in the weight of the entire sound insulation structures 1 and 6 can be suppressed, and this sound insulation structures 1 and 6 can be easily and stably mounted on mounting surfaces of various shapes including, for example, curved surfaces. That is, a lightweight sound insulation structure 1 and 6 with good sound insulation in the low frequency band can be provided. Note that if there are too few support wall portions 3d with a high height, it becomes difficult to stably support the sound insulation structures 1 and 6, and if there are too many, the weight of the entire sound insulation structures 1 and 6 increases. Therefore, it is preferable that the section 5 surrounded by the support wall portions 3d with a high height is 5% or more of the total sections 5 of the sound insulation structures 1 and 6. Also, when looking at the cross section parallel to the film portion 2 of each support wall portion 3c and 3d, it is preferable that the total cross-sectional area of the support wall portions 3d with a high height is 10% or more of the total cross-sectional area of all the support wall portions 3c and 3d of the sound insulation structures 1 and 6. In Example 11, of the film portion 2 having a square planar shape of 25 mm × 25 mm, 20 mm × 20 mm (area 400 cm 2In the region of , as shown in Fig. 21A, 49 compartments 5 are provided in a 7×7 arrangement. Among them, 16 compartments 5 are surrounded by the high support wall portions 3d, and the ratio is 32.6%, which is preferable.

[0079] Note that, even when all the support wall portions 3 have a high height as in Example 10, or when only some of the support wall portions 3d have a high height as in Example 11, in order to suppress an increase in the weight of the entire sound insulation structures 1 and 6 and installation restrictions, it is preferable that the height of the entire sound insulation structures 1 and 6 is 20 mm or less as described above.

[0080] Referring to Fig. 14J, it can be seen that even when the film portion 2 and the support wall portion 3 are formed by integral molding of a thermoplastic material, good sound insulation can be obtained by providing the weight portion 4. In the spring-mass resonator composed of the spring portion 4a and the mass portion 4b of the weight portion 4 as in Example 13, it can be seen that when the spring portion 4a is softer, the resonance frequency shifts to the low-frequency side, and a large sound insulation effect can be obtained on the low-frequency side. By thus changing the configuration of the weight portion 4, adjustment of the sound insulation frequency band is possible. Also, as in Example 14, it can be seen that good sound insulation can be obtained even when the weight portion 4 is composed of a single material. Therefore, productivity can be improved by manufacturing the weight portion with a single material.

[0081] Referring to Fig. 14K, it can be seen that when the film portion 2 is made of a thin resin material (film), the sound insulation performance deteriorates, so it is preferable that the film portion 2 has a certain thickness. Compared with an elastomer material such as EPDM in Example 1, a resin material such as LDPE in Comparative Example 6 is hard, so it is conceivable to reduce the film thickness. However, if the film thickness is less than a certain level, the film portion 2 is too soft, and it is considered that vibrations sufficient for the spring-mass resonator composed of the spring portion 4a and the mass portion 4b of the weight portion 4 to function properly are not transmitted to the weight portion 4. Therefore, it is preferable that the film portion 2 has a thickness of a certain level or more.

[0082] [Sound insulation structure] The sound insulation structure 11 that includes the sound insulation structures 1 and 6 of the present invention described above, enhances sound insulation performance, and is easy to install will be described. First, a side view of an automobile, which is an example of a vehicle in which the sound insulation structure 11 is provided, is shown in FIG. 22. The sound insulation structure 11 of the present invention is arranged so as to overlap a panel (dash panel) 14 provided at the boundary between the engine room 12 and the passenger compartment 13 of the automobile. A side view of the sound insulation structure 11 is shown in FIG. 23, a perspective view seen from the front side thereof is shown in FIG. 24, and a cross-sectional view taken along line C-C of FIG. 24 is shown in FIG. 25. The sound insulation structure 11 is composed of a sound insulation plate-like part 10 and a sound insulation structure part 9 that are arranged side by side in a plane. This sound insulation structure part 9 has the same configuration as any one of the sound insulation structures 1 and 6 of the present invention described above. That is, the sound insulation structure part 9 is composed of any one of the sound insulation structures 1 and 6 of the present invention described above. In this example, a sound insulation structure 11 is configured in which a large-area sound insulation plate-like part 10 and two sound insulation structure parts 9 are integrally formed or joined to each other and can be handled as one part.

[0083] The sound insulation plate-like part 10 has a single-layer structure composed of either a layer made of a sound-absorbing material such as felt, polyurethane foam, or glass wool, or a layer made of a sound-insulating material such as a resin film or a rubber sheet, or a laminated structure thereof. The sound insulation plate-like part 10 is a plate-like member having a shape along the panel 14, and the thickness may vary depending on the part. As an example, in the sound insulation plate-like part 10, there are parts with a thickness of less than 5 mm to parts with a thickness of about 40 mm. The sound insulation plate-like part 10 may have a configuration substantially the same as or similar to that of the dash silencer described in Patent Documents 1 and 2.

[0084] An example of the sound insulation structure portion 9 has the same configuration as the sound insulation structure 1 shown in FIGS. 1A to 2B. That is, the sound insulation structure portion 9 is composed of the sound insulation structure 1 of the present invention described above. This sound insulation structure portion 9 has an elastic sheet-like film portion 2, a support wall portion 3 that stands substantially vertically from the film portion 2 and has elasticity, and a weight portion 4 that stands substantially vertically from the film portion 2 and has elasticity. Each of the weight portions 4 located in each compartment 5 constitutes a spring-mass resonator having an elastic spring portion 4a and a mass portion (mass portion) 4b having a larger mass than the spring portion 4a. Since this sound insulation structure portion 9 has the same configuration as the sound insulation structure 1 shown in FIGS. 1A to 2B, as described above, the vibration of the film portion 2 is controlled by the action of the spring-mass resonator constituted by the spring portion 4a and the mass portion 4b of the weight portion 4. In particular, in a specific frequency range (for example, a frequency of 1000 Hz or less), the film vibration is significantly reduced, and high sound insulation performance is exhibited.

[0085] In this sound insulation structure 11, the sound insulation structure portion 9 having the above-described configuration is disposed at a portion where sound propagation is particularly large in a vehicle or the like. In the example shown in FIG. 22, the sound insulation structure 11 is disposed so as to overlap a panel 14 located at the boundary between the engine room 12 and the passenger compartment 13 of an automobile. And the sound insulation structure portions 9 are respectively disposed at two locations facing the front wheel tires, which are particularly large in the propagation of road noise. If the entire sound insulation structure 11 disposed so as to overlap the panel 14 is composed of the sound insulation structure portion 9 having the above-described configuration, the sound insulation effect is high, but the weight of the sound insulation structure 11 is large, which may have an adverse effect on the performance of the vehicle. On the other hand, in the sound insulation structure 11 of the present embodiment, the sound insulation structure portion 9 having a particularly large sound insulation effect is disposed at a portion where sound propagation is large (for example, a position facing the tire), and a sound insulation plate-like portion 10 having a simple structure is disposed at a portion where sound propagation is not so large (a position other than the position facing the tire). Thereby, while suppressing an increase in weight to a small extent, it is possible to efficiently suppress the entry of sound. And not only the sound insulation plate-like portion 10 formed in accordance with the shape of the panel 14 but also the sound insulation structure portion 9 can be easily and stably installed without being fixed to mounting surfaces of various shapes by adhesion or the like. Therefore, the sound insulation structure 11 of the present embodiment can be laminated and stably held on a panel 14 having a complicated shape.

[0086] In this example, on one main surface of the sound insulation structure 11 (the surface facing the passenger compartment 13, which faces the right side in FIGS. 22 and 23 and is mainly shown in FIG. 24 as a wide surface), the area occupied by the sound insulation structure portion 9 is preferably 5% or more and 95% or less of the entire area of the sound insulation structure 11, more preferably 10% or more and 40% or less, and even more preferably 20% or more and 30% or less. If the ratio of the area occupied by the sound insulation structure portion 9 is too small, the sound insulation performance of the sound insulation structure 11 equivalent to a dash silencer will be insufficient. Also, if the ratio of the area occupied by the sound insulation structure portion 9 is too large, the noise propagated to the passenger compartment side through the sound insulation structure 11 will be reflected by the instrument panel and hit and re-reflect on the surface of the sound insulation structure 11 where the sound-absorbing material is not laminated, resulting in an increase in sound pressure and the occurrence of a stuffy sound. In the examples shown in FIGS. 22 to 25, the area occupied by the sound insulation structure portion 9 is about 30% of the entire area of the sound insulation structure 11.

[0087] In this example, the sound insulation plate-like portion 10 and the sound insulation structure portion 9 are integrated. Specifically, at least one of the layer of the sound insulation material (such as felt, urethane, glass wool, etc.) or the layer of the sound insulation material (such as resin film, rubber sheet, etc.) constituting the sound insulation plate-like portion 10 and the film portion 2 and the support wall portion 3 of the sound insulation structure portion 9 are integrally formed by insert molding or the like, or are joined to each other by any of ultrasonic welding, adhesion with a hot melt adhesive, fixing by a clip, a bolt or a rivet. Thereby, the sound insulation structure 11 composed of the sound insulation plate-like portion 10 and the sound insulation structure portion 9 can be easily handled.

[0088] The sound insulation structure 11 of the present invention is not only the sound insulation plate-like portion 10, but also the sound insulation structure portion 9 described above is very thin and lightweight, and since it is easy to place on a surface having a curved surface or unevenness, it is suitable for being placed and used on a panel of a vehicle, particularly an automobile (for example, the panel 14 shown in FIGS. 1A to 1B). Examples of the panel on which the sound insulation structure 11 is placed may be the same as the panel on which the sound insulation structures 1 and 6 described above are placed. The arrangement method, position, and usage form of the sound insulation structure 11 may be the same as the arrangement method, position, and usage form of the sound insulation structures 1 and 6 described above.

[0089] In addition, the sound insulation structure 11 of the present invention has a sound insulation structure portion 9 having the same configuration as the sound insulation structures 1 and 6 exemplified in the above-described Examples 1 to 14, and in addition, includes a sound insulation plate-like portion 10. Therefore, it can be said that the difference in sound insulation performance of the sound insulation structures 1 and 6 in Examples 1 to 14 represents the difference in sound insulation performance of each sound insulation structure 11. Further, in addition to the fact that the sound insulation structures 1 and 6 in Examples 1 to 14 have greater sound insulation performance than the structures in Comparative Examples 1 to 6 as described above, the sound insulation structure 11 of the present invention is considered to exhibit even more excellent sound insulation performance by the amount corresponding to the provision of the sound insulation plate-like portion 10.

[0090] The present invention includes the following configurations. [1] A film portion having elasticity, a support wall portion standing on the film portion and having elasticity, and a weight portion standing on the film portion. The film portion is divided into a plurality of compartments by the support wall portion, and the weight portions are respectively located inside all of the plurality of compartments or inside some of the plurality of compartments. In the compartments in which the weight portions are located, one weight portion is arranged in one compartment. The height of the support wall portion extending in the direction perpendicular to the film portion is greater than the height of the weight portion extending in the direction perpendicular to the film portion. The film portion constitutes a spring-mass resonator as a spring portion, and the weight portion constitutes a mass portion. Each of the compartments is sealed by the film portion on the film portion side. The weight portion is located in a space surrounded by the support wall portion. The sound insulation structure is characterized in that the supporting wall portion has a dynamic storage elastic modulus of 0.01 MPa or more and 100 MPa or less at a frequency of 1 Hz to 1000 Hz at 23°C. [2] Both the film portion and the supporting wall portion are each made of any one of a material having no energy elasticity but having rubber elasticity, a material having no rubber elasticity but having energy elasticity, and a material having both rubber elasticity and energy elasticity. The sound insulation structure according to [1]. [3] The film portion has a dynamic storage elastic modulus of 0.01 MPa or more and 100 MPa or less at a frequency of 1 Hz to 1000 Hz at 23°C. The sound insulation structure according to [1] or [2]. [4] Both the film portion and the supporting wall portion have a loss tangent of 0.01 or more and 0.50 or less at a frequency of 1 Hz to 1000 Hz at 23°C. The sound insulation structure according to any one of [1] to [3]. [5] The supporting wall portion includes a plurality of first wall portions extending in a direction perpendicular to the film portion and extending in a first direction parallel to the film portion, and a plurality of second wall portions extending in a direction perpendicular to the film portion and extending in a second direction perpendicular to the first direction. The sound insulation structure according to any one of [1] to [4]. [6] The supporting wall portion is cylindrical having a circular, elliptical or oval cross-sectional shape defining each of the compartments, or is angular cylindrical having a polygonal cross-sectional shape defining each of the compartments. The sound insulation structure according to any one of [1] to [5]. [7] The area of each of the compartments is 100 mm 2 or more and 1000 mm 2 or less. The sound insulation structure according to any one of [1] to [6]. [8] 10 or more and 1000 or less of the compartments are provided per 1000 cm 2 of the area of the film portion. The sound insulation structure according to any one of [1] to [7]. [9] 50 or more and 500 or less of the compartments are provided per 1000 cm 2 of the area of the film portion. The sound insulation structure according to [8].

[10] The sound insulation structure according to any one of [1] to [9], wherein the thickness of the support wall portion is 0.5 mm or more and 5.0 mm or less.

[11] The sound insulation structure according to

[10] , wherein the thickness of the support wall portion is 1.0 mm or more and 3.0 mm or less.

[12] The sound insulation structure according to any one of [1] to

[11] , wherein the thickness of the film portion is 0.1 mm or more and 3.0 mm or less.

[13] The sound insulation structure according to any one of [1] to

[12] , wherein the height in the direction orthogonal to the film portion is 5 mm or more and 20 mm or less.

[14] The sound insulation structure according to any one of [1] to

[13] , wherein the height of the support wall portion extending in the direction orthogonal to the film portion is 5 mm or more and 20 mm or less.

[15] The sound insulation structure according to

[14] , wherein the height of the support wall portion extending in the direction orthogonal to the film portion is 10 mm or more and 20 mm or less.

[16] The sound insulation structure according to any one of [1] to

[15] , which has a plurality of the support wall portions, and the height of some of the support wall portions extending in the direction orthogonal to the film portion is higher than that of the other support wall portions.

[17] The sound insulation structure according to

[16] , wherein the height of the support wall portion having a higher height extending in the direction orthogonal to the film portion is greater than 10 mm and 20 mm or less, and the height of the other support wall portions is 10 mm or less.

[18] The sound insulation structure according to any one of [1] to

[17] , wherein the height of the weight portion extending in the direction orthogonal to the film portion is 1 mm or more.

[19] The sound insulation structure according to any one of [1] to

[18] , wherein the Shore A hardness of the film portion is 30 or more, and the Shore A hardness of the support wall portion is 1 or more and 90 or less.

[20] A sound insulation structure comprising a sound insulation plate-shaped portion and a sound insulation structure portion, wherein the sound insulation plate-shaped portion is a plate-shaped member made of a sound absorption material or a sound insulation material, and the sound insulation structure portion is composed of the sound insulation structure according to any one of [1] to

[19] . At least one of the film portion and the support wall portion and the sound insulation plate-like portion are integrally formed or joined to each other, and the sound insulation plate-like portion and the sound insulation structure portion are arranged side by side in a plane. A sound insulation structure characterized by this.

[21] The sound insulation structure according to

[20] , wherein on the main surface of the sound insulation structure, the area occupied by the sound insulation structure portion is 5% or more and 95% or less of the total area of the sound insulation structure.

[22] At least one of the film portion and the support wall portion and the sound insulation plate-like portion are integrally formed by insert molding, or joined to each other by any one of ultrasonic welding, adhesion with a hot melt adhesive, fixing by a clip, a bolt or a rivet. The sound insulation structure according to

[20] or

[21] .

[23] The sound insulation plate-like portion has a single-layer structure composed of either a layer made of felt, urethane or glass wool and a layer made of a resin film or a rubber sheet, or a multilayer structure in which they are laminated. The sound insulation structure according to any one of

[20] to

[22] .

[24] The sound insulation structure according to any one of

[20] to

[23] , which is attached to an interior panel of an automobile.

[25] The sound insulation structure according to

[24] , which is attached to a dashboard of an automobile, and the sound insulation structure portions are respectively provided at positions facing the tires.

Explanation of reference numerals

[0091] 1,6 Sound insulation structure 2 Film portion 3 Support wall portion 3a First wall portion 3b Second wall portion 3c Support wall portion with low height (other support wall portions) 3d Support wall portion with high height (some support wall portions) 4,7 Weight portion 4a Spring portion 4b Mass portion 5 Compartment 8 Iron plate 9 Sound insulation structure portion 10 Sound insulation plate-like portion 11 Sound insulation structure 12 Engine room 13 Passenger compartment 14 Panel (dash panel)

Claims

1. It has an elastic film part, a support wall part that stands on the film part and has elasticity, and a weight part that stands on the film part. The film part is divided into a plurality of compartments by the support wall part, and the weight parts are respectively located inside all of the plurality of compartments or inside some of the plurality of compartments. In the compartments where the weight parts are located, one weight part is arranged in one compartment. The height of the support wall part extending in the direction orthogonal to the film part is greater than the height of the weight part extending in the direction orthogonal to the film part. The film part serves as a spring part, and the weight part serves as a mass part to form a spring-mass resonator. Each of the compartments is sealed by the film part on the film part side. The weight part is located in a space surrounded by the support wall part. The support wall part is a sound insulation structure characterized in that the dynamic storage modulus at 23°C in the frequency range of 1 Hz to 1000 Hz is 0.01 MPa or more and 100 MPa or less.

2. Both the film part and the support wall part are made of any one of a material having no energy elasticity but having rubber elasticity, a material having no rubber elasticity but having energy elasticity, and a material having both rubber elasticity and energy elasticity. The sound insulation structure according to Claim 1.

3. The film part is the sound insulation structure according to Claim 1, wherein the dynamic storage modulus at 23°C in the frequency range of 1 Hz to 1000 Hz is 0.01 MPa or more and 100 MPa or less.

4. Both the film part and the support wall part are the sound insulation structure according to Claim 1, wherein the loss tangent at 23°C in the frequency range of 1 Hz to 1000 Hz is 0.01 or more and 0.50 or less.

5. The support wall part includes a plurality of first wall parts extending in a direction orthogonal to the film part and in a first direction parallel to the film part, and a plurality of second wall parts extending in a direction orthogonal to the film part and in a second direction orthogonal to the first direction. The sound insulation structure according to Claim 1.

6. The support wall part is cylindrical having a circular, elliptical or oval cross-sectional shape defining each of the compartments, or rectangular tubular having a polygonal cross-sectional shape defining each of the compartments. The sound insulation structure according to Claim 1.

7. The area of each of the said sections is 100 mm 2 or more and 1000 mm 2 or less. The sound insulation structure according to claim 1.

8. The area of the film part is 1000 cm 2 The sound insulation structure according to claim 1, wherein 10 or more and 1000 or less of the partitions are provided per cm

9. The area of the film part is 1000 cm 2 The sound insulation structure according to claim 8, wherein 50 or more and 500 or less of the partitions are provided per area.

10. The sound insulation structure according to Claim 1, wherein the plate thickness of the support wall part is 0.5 mm or more and 5.0 mm or less.

11. The sound insulation structure according to claim 10, wherein the thickness of the support wall portion is 1.0 mm or more and 3.0 mm or less.

12. The sound insulation structure according to claim 1, wherein the thickness of the film portion is 0.1 mm or more and 3.0 mm or less.

13. The sound insulation structure according to claim 1, wherein the height in the direction orthogonal to the film portion is 5 mm or more and 20 mm or less.

14. The sound insulation structure according to claim 1, wherein the height of the support wall portion extending in the direction orthogonal to the film portion is 5 mm or more and 20 mm or less.

15. The sound insulation structure according to claim 14, wherein the height of the support wall portion extending in the direction orthogonal to the film portion is 10 mm or more and 20 mm or less.

16. The sound insulation structure according to claim 1, having a plurality of the support wall portions, wherein a height of some of the support wall portions extending in the direction orthogonal to the film portion is higher than that of the other support wall portions.

17. The sound insulation structure according to claim 16, wherein the height of the support wall portion having a higher height extending in the direction orthogonal to the film portion is greater than 10 mm and 20 mm or less, and the height of the other support wall portions is 10 mm or less.

18. The sound insulation structure according to claim 1, wherein the height of the weight portion extending in the direction orthogonal to the film portion is 1 mm or more.

19. The sound insulation structure according to claim 1, wherein the durometer A hardness of the film portion is 30 or more, and the durometer A hardness of the support wall portion is 1 or more and 90 or less.

20. A sound insulation structure comprising a sound insulation plate-like portion and a sound insulation structure portion, wherein the sound insulation plate-like portion is a plate-like member made of a sound-absorbing material or a sound-insulating material, the sound insulation structure portion is composed of the sound insulation structure according to claim 1, and at least one of the film portion and the support wall portion and the sound insulation plate-like portion are integrally formed or joined to each other, and the sound insulation plate-like portion and the sound insulation structure portion are arranged side by side in a plane. A sound insulation structure characterized by this.

21. The sound insulation structure according to claim 20, wherein the area occupied by the sound insulation structure portion on the main surface of the sound insulation structure is 5% or more and 95% or less of the total area of the sound insulation structure.

22. At least one of the film portion and the support wall portion and the sound insulation plate-like portion are integrally formed by insert molding, or joined to each other by any one of ultrasonic welding, adhesion with a hot melt adhesive, fixing with a clip, a bolt or a rivet. The sound insulation structure according to claim 20 or 21.

23. The sound insulation panel-shaped part has a single-layer structure composed of either a layer made of felt, urethane, or glass wool, or a layer made of a resin film or a rubber sheet, or a multilayer structure in which they are laminated. The sound insulation structure according to claim 20 or 21.

24. The sound insulation structure according to claim 20 or 21, which is attached to an interior panel of an automobile.

25. The sound insulation structure according to claim 24, which is attached to a dash panel of an automobile, and the sound insulation structure parts are respectively provided at positions facing the tires.

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