Soundproof structure

Abstract

To provide a thin and light-weight soundproof structure that can provide sufficient sound insulating properties, and can be easily and stably mounted on at least part of a member that partially separates a cabin of an automobile, which may have a curved surface or irregularities, from the outside of the automobile.SOLUTION: A soundproof structure 1 is arranged at at least part of a member that partially separates a cabin of an automobile from the outside of the automobile, and has a film part 2 having elasticity, support wall parts 3 erected on the film part 2 and having elasticity, and weight parts 4 erected on the film part 2. The film part 2 is divided into a plurality of sections by the support wall parts 3, and the weight parts 4 are located inside all the sections or some of the sections. One weight part 4 is arranged in one section. The height of the support wall part 3 extending in a direction orthogonal to the film part 2 is larger than the height of the weight part 4 extending in the direction orthogonal to the film part 2. Each of the weight parts 4 forms a spring-mass resonator having a spring part 4a having elasticity and a mass part 4b having a larger mass than the spring part 4a.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a soundproof structure. [Background technology]

[0002] In recent years, there has been a demand for reducing noise in the interior of an automobile to provide a quiet and comfortable space for occupants by blocking out noises such as road noise, tire pattern noise, wind noise, and engine noise. Therefore, there is a demand for means for suppressing the propagation of noise and vibration from the outside of the automobile to the inside, and also for the propagation of noise and vibration from the outside of the passenger compartment to the passenger compartment within the automobile, i.e., for members with high soundproofing properties. In recent years, there has been a demand for lightweight soundproofing members to improve the energy efficiency of automobiles. Examples of soundproofing structures installed in automobiles and the like are disclosed in Patent Documents 1 to 11.

[0003] The sound-absorbing material disclosed in Patent Document 1 is a breathable plate-like material made by mixing a binder resin into a fiber material and then heat-molding it into a shape with multiple bends. The sound-absorbing material is tightly inserted into the space between the front fender panel and the engine compartment, and the space between the rear fender panel and the trunk, and the space is divided into three or more small spaces.

[0004] In the rear sound insulation structure for an automobile disclosed in Patent Document 2, the pillar trim has retractor lateral portions close to the interior surface of the retractor, and retractor front and rear recesses extending along the interior side surface of the vehicle body side portion. A sealant is provided between the retractor front and rear recesses and the interior side surface of the vehicle body side portion, and a shielding portion that suppresses noise from entering the space formed between the interior side surface of the vehicle body side portion and the pillar trim is formed by the retractor, the retractor front and rear recesses, and the sealant.

[0005] The vehicle body structure disclosed in Patent Document 3 includes a plate that separates the vehicle into a passenger compartment and an exterior space, and multiple sound-absorbing structures attached to the plate that absorb sound through sound pressure drive. Each of the multiple sound-absorbing structures includes a diaphragm and an air space defined behind the diaphragm. The chassis that serves as the base of the vehicle body structure constitutes part of the multiple sound-absorbing structures. The multiple sound-absorbing structures each have different dimensions, with larger sound-absorbing structures being located in areas on the plate where sound pressure is higher.

[0006] The vehicle body structure disclosed in Patent Document 4 includes hollow supports that support the vehicle roof, a plate sound absorber that absorbs sound by sound pressure drive, and joining means that joins the plate sound absorber to the supports. The plate sound absorber includes a housing with an opening, a diaphragm that is supported by the housing at the opening, and an air space defined within the housing.

[0007] The vehicle body structure disclosed in Patent Document 5 has a roof supported by vehicle pillars and a sound-absorbing structure attached to the roof that absorbs sound by sound pressure drive. The sound-absorbing structure is composed of a combination of a plate sound absorber having a diaphragm and an air space defined behind the diaphragm, and a Helmholtz sound absorber having an enclosed space and a tubular member connecting the enclosed space to the outside. Multiple plate sound absorbers are arranged on the flat portion of the roof, and Helmholtz sound absorbers are arranged on the sloping portion of the roof.

[0008] The vehicle disclosed in Patent Document 6 has a fender protector attached inside the wheelhouse, with a rib erected on the surface (back surface) of the fender protector facing the wheelhouse, and sound-absorbing material covering the rib and attached with at least its peripheral edge in close contact with the back surface of the fender protector or the back surface of the rib, with the portion abutting the rib raised above the back surface of the fender protector. The space surrounded by the back surface of the fender protector, the sides of the rib, and the sound-absorbing material constitutes a closed sound-absorbing air chamber. The sound-absorbing material is heat-welded to the fender protector, and the outer surface of the sound-absorbing material is abutted against a body panel that constitutes the wheelhouse of the vehicle. A closed second sound-absorbing air chamber is formed between the body panel and a recessed portion that is heat-welded to the back surface of the fender protector or the back surface of the rib.

[0009] The sound-absorbing member disclosed in Patent Document 7 has a plurality of first recesses and a plurality of second recesses, the first recesses and the second recesses having different opening shapes and different internal space sizes, and has a maximum peak in the 1 / 3 octave band center frequency range of 1000 Hz to 4000 Hz, with the reverberation chamber sound absorption coefficient of the maximum peak being 0.75 or more. One example of the use of this sound-absorbing member is that it is attached to the door panel of an automobile.

[0010] The invention described in Patent Document 8 is an acoustic damping panel comprising a rigid frame divided into a plurality of individual cells, a sheet of flexible material, and a plurality of weights, each weight being fixed to the sheet of flexible material so that each cell is provided with its own weight, and the attenuated sound is controlled by appropriate selection of the mass of the weights.

[0011] In the invention described in Patent Document 9, in a soundproofing material comprising an elastic sheet and a support portion that holds the sheet and divides the sheet into partitions, the relationship between the rigidity of the sheet in the partitions and the surface density of the sheet is specified.

[0012] The sound-proofing material of the invention described in Patent Document 10 is a structure comprising a flat substrate portion and a plurality of resonating portions connected to the substrate portion and having a predetermined resonant frequency, each of the plurality of resonating portions having a weight portion and a connecting portion that connects the weight portion to the substrate portion, and is configured so that, in a projection view seen from a direction perpendicular to the substrate portion, the center of gravity of the resonating portion is located outside the joint area between the substrate portion and the connecting portion.

[0013] The vibration reduction device of the invention described in Patent Document 11 has an acoustic meta-structure that is attached to the vehicle body and blocks vibrations transmitted through the vehicle body, and includes a cross-shaped frame that is attached to the vehicle body and divides a certain space into certain areas, and vibrators that are configured at the corners of each area divided by the frame and have their own natural frequencies, blocking vibrations transmitted from the vehicle body through the frame. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] Patent No. 5283194 [Patent Document 2] Patent No. 5880352 [Patent Document 3] Patent No. 5428170 [Patent Document 4] Patent No. 5402120 [Patent Document 5] Patent No. 5286856 [Patent Document 6] Patent No. 5508692 [Patent Document 7] Japanese Patent Application Publication No. 2019-184798 [Patent Document 8] Japanese Patent Application Laid-Open No. 2005-250474 [Patent Document 9] Patent No. 6879369 [Patent Document 10] Patent Publication No. 2021-152584 [Patent Document 11] Japanese Patent Publication No. 2020-91481 Summary of the Invention [Problem to be solved by the invention]

[0015] The invention described in Patent Document 1 aims to minimize noise intrusion from the space between the front fender panel and the engine compartment and the space between the rear fender panel and the trunk compartment. The invention described in Patent Document 2 aims to reduce noise intrusion from the rear pillars and trunk sides, the invention described in Patent Document 3 aims to reduce noise intrusion from the trunk compartment, the invention described in Patent Document 4 aims to reduce noise intrusion from the rear pillars, the invention described in Patent Document 5 aims to reduce noise intrusion from the roof, and the invention described in Patent Document 6 aims to reduce noise intrusion from the fenders. However, none of the configurations described in Patent Documents 1 to 6 have a special soundproofing structure, and are unable to sufficiently reduce noise intrusion into the vehicle cabin.

[0016] Patent Document 7 aims to reduce the intrusion of noise through the door, and the sound-absorbing material of Patent Document 7 has a large number of first recesses and a large number of second recesses arranged side by side, which enables it to exert a sound-absorbing effect, but it does not have a high sound-proofing effect, and it is difficult to sufficiently reduce the noise that enters the vehicle interior.

[0017] The acoustic damping panel described in Patent Document 8 has an inflexible, rigid frame, and vibrations are transmitted to the seat via this rigid frame, which may result in insufficient sound insulation. Furthermore, if the mounting surface on which the rigid frame is placed is curved or uneven, the acoustic damping panel may not be stably supported. In particular, since many components in typical automobiles are curved or uneven, it is difficult to easily use the acoustic damping panel described in Patent Document 8 as an automotive soundproofing material. Furthermore, rigid frames have a large mass, and the increased mass of the soundproofing material in an automobile poses a problem.

[0018] The soundproofing material described in Patent Document 9 has a high support portion, i.e., a height extending from the seat in a direction perpendicular to the seat, preferably 25 mm or more. In order to stably support the seat with such a high support portion, the support portion preferably has rigidity. As a result, vibrations may be transmitted through the support portion, which may result in insufficient sound insulation, and it may be difficult to mount the soundproofing material on curved or uneven automotive components. Furthermore, such a high support portion increases the overall size and weight of the soundproofing material. If the soundproofing material is mounted on an interior component of the vehicle, it may occupy a large amount of space inside the vehicle, reducing space efficiency, interfering with the installation of other components, or becoming a nuisance to the occupants.

[0019] The sound-insulating material described in Patent Document 10 has a resonating section, which is the functional part that provides sound insulation, exposed and not covered by a supporting wall, etc., and if this resonating section comes into contact with other members or the human body, there is a risk that the sound-insulating properties will be reduced or changed. Therefore, it is necessary to provide a large space around the resonating section, which reduces space efficiency.

[0020] The vibration reduction device described in Patent Document 11 does not have a membrane portion, but consists of multiple vibrators and a frame connecting them. Therefore, like the sound-insulating material of Patent Document 10, the vibrators, which are the functional components that provide the sound-insulating effect, are exposed, and if other components or the human body come into contact with these vibrators, the sound-insulating properties may be reduced or changed. Furthermore, the frame must be rigid to ensure a minimum structural strength for the vibration reduction device. As a result, vibrations are transmitted through the frame, which may result in insufficient sound insulation. Furthermore, it is difficult to mount the vibration reduction device described in Patent Document 11 on curved or uneven automotive components.

[0021] Although the structures described in Patent Documents 1 to 6 have one objective of making the interior of an automobile quieter, they do not propose any special soundproofing structure for suppressing noise from entering the interior of the vehicle. Furthermore, none of the structures described in Patent Documents 1 to 11 provide sufficient soundproofing against noise entering the interior of the vehicle, and a soundproofing structure with better soundproofing is desired.

[0022] Therefore, an object of the present invention is to provide a thin and lightweight soundproofing structure that can provide sufficient soundproofing and can be easily and stably placed on at least a part of a member that partially separates the interior of an automobile from the outside of the automobile, which may have a curved or uneven surface, and that has good soundproofing properties, particularly against noise in the low frequency range of 1000 Hz or less. [Means for solving the problem]

[0023] The soundproof structure of the present invention is arranged on at least a part of a member that partially separates the passenger compartment of an automobile from the outside of the automobile, and comprises an elastic membrane portion, an elastic support wall portion standing on the membrane portion, and a weight portion standing on the membrane portion, the membrane portion is divided into a plurality of compartments by the support wall portion, the weight portion is located inside all of the plurality of compartments or inside some of the plurality of compartments, each of the weight portions is located in one of the compartments, the height of the support wall portion extending in a direction perpendicular to the membrane portion is greater than the height of the weight portion extending in a direction perpendicular to the membrane portion, and each of the weight portions constitutes a spring-mass resonator having an elastic spring portion and a mass portion having a mass greater than that of the spring portion. The term "elasticity" used here refers to the property of a solid substance that has been deformed by an external force and then returns to its original shape when the external force is removed, and includes energy elasticity and rubber elasticity (entropy elasticity). Here, a substance is said to have "elasticity" if it has at least one of energy elasticity and rubber elasticity (entropy elasticity). The membrane portion, the support wall portion and the spring portion may all be made of a material that has rubber elasticity but not energy elasticity, a material that has energy elasticity but not rubber elasticity, or a material that has both rubber elasticity and energy elasticity. The film portion, the support wall portion, and the spring portion may all have a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at 23° C. and a frequency of 1 Hz to 1000 Hz. The film portion, the support wall portion, and the spring portion may all have a loss tangent of 0.01 or more and 0.50 or less at 23° C. and a frequency of 1 Hz to 1000 Hz. Specifically, the elasticity of the membrane, supporting wall, and spring portions is evaluated by measuring frequency dependency in tension or compression mode with a dynamic viscoelasticity measuring device in accordance with JIS K 7244, and determining a master curve based on 23° C., and the dynamic storage modulus (E') is 0.01 MPa or more and 100 MPa or less at 23° C. and frequencies of 1 Hz to 1000 Hz. Even more preferably, the membrane and supporting wall portions each have a dynamic storage modulus (E') of 0.05 MPa or more and 50 MPa or less at 23° C. and frequencies of 1 Hz to 1000 Hz, and a loss tangent of 0.05 to 0.45 at 23° C. and frequencies of 1 Hz to 1000 Hz. The spring portion may be located on the side of the weight portion attached to the membrane portion, and the mass portion may be located on the opposite side of the weight portion from the side attached to the membrane portion. The mass portion may have a larger volume than the spring portion. The mass portion may be made of a material having a higher density than the spring portion. Another soundproofing structure of the present invention is arranged on at least a part of a member that partially separates the passenger compartment of an automobile from the outside of the automobile, and comprises an elastic membrane portion, an elastic support wall portion standing on the membrane portion, and a weight portion standing on the membrane portion, the membrane portion being divided into a plurality of compartments by the support wall portion, the weight portion being located inside all of the plurality of compartments or inside some of the plurality of compartments, each of the weight portions being located in one of the compartments, the height of the support wall portion extending in a direction perpendicular to the membrane portion being greater than the height of the weight portion extending in a direction perpendicular to the membrane portion, and the membrane portion acting as a spring portion and the weight portion acting as a mass portion constituting a spring-mass resonator. Both the membrane portion and the support wall portion may be made of a material that has rubber elasticity but not energy elasticity, a material that has energy elasticity but not rubber elasticity, or a material that has both rubber elasticity and energy elasticity. The membrane portion and the supporting wall portion may both have a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at a frequency of 1 Hz to 1000 Hz at 23° C. Furthermore, the membrane portion and the supporting wall portion may both 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. More preferably, the membrane portion and the supporting wall portion may both 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 of 0.05 or more and 0.45 or less at a frequency of 1 Hz to 1000 Hz at 23° C. In the soundproofing structure of the present invention and another soundproofing structure, the support wall portion may include a plurality of first wall portions extending in a direction perpendicular to the membrane portion and extending in a first direction parallel to the membrane portion, and a plurality of second wall portions extending in a direction perpendicular to the membrane portion and extending in a second direction perpendicular to the first direction. The support wall portion may be cylindrical with a circular, elliptical or oval cross-sectional shape that defines each of the compartments, or may be rectangular with a polygonal cross-sectional shape that defines each of the compartments, specifically a square, regular pentagon or regular hexagonal cross-sectional shape. The area of ​​each of the compartments is 100 mm 2 More than 1000mm 2 It may be the following: The area of ​​the membrane is 1000 cm 2 More preferably, the membrane portion has an area of ​​1000 cm or more and 1000 or less of the compartments. 2 There may be 50 to 500 of the compartments per unit area. The support wall portion may have a thickness of 0.5 mm or more and 5.0 mm or less. More preferably, the support wall portion may have a thickness of 1.0 mm or more and 3.0 mm or less. The membrane portion may have a thickness of 0.1 mm or more and 3.0 mm or less. The height in the direction perpendicular to the film portion may be 5 mm or more and 20 mm or less. The height of the support wall portion extending from the film portion in a direction perpendicular to the film portion may be 5 mm or more and 20 mm or less, and the height may vary in parts. The height of the weight portion extending from the film portion in a direction perpendicular to the film portion may be 1 mm or more. The film portion may have a durometer A hardness of 50 or more, and the support wall portion may have a durometer A hardness of 1 or more and 90 or less. The durometer A hardness can be obtained by measurement in accordance with JIS K 6253-3. The soundproof structure may be arranged in at least one of the roof of an automobile (including engine vehicles, electric vehicles, fuel cell vehicles, and hybrid vehicles), a pillar supporting the roof, a door trim, a fender liner that partially covers a tire, a trunk side, and a trunk trim. The acoustic structure may be located inside the electric vehicle. [Effects of the Invention]

[0024] According to the present invention, it is possible to provide a thin and lightweight soundproofing structure that can provide sufficient soundproofing and can be easily and stably placed on at least a part of a member that partially separates the interior of an automobile from the outside of the automobile, which may have a curved or uneven surface, and that has good soundproofing properties particularly in the low frequency range of 1000 Hz or less. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a side view of an automobile provided with a soundproof structure according to a first embodiment of the present invention. [Figure 2] 2A is a perspective view of the automobile shown in FIG. 1 as seen from the front, and FIG. 2B is a perspective view as seen from the rear. [Figure 3] FIG. 1A is a perspective view of a soundproof structure according to a first embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA thereof. [Figure 4] 4(A) is an exploded perspective view of one section of the soundproof structure shown in FIG. 3, and FIG. 4(B) is an exploded front view thereof. [Figure 5] FIG. 3 is a cross-sectional view of another example of the configuration of the soundproof structure of the first embodiment of the present invention. [Figure 6] FIG. 4 is a cross-sectional view of yet another example of the configuration of the soundproof structure of the first embodiment of the present invention. [Figure 7] FIG. 2 is an enlarged side view of a portion of the automobile shown in FIG. [Figure 8] FIG. 2 is a perspective view of a door portion of the automobile shown in FIG. [Figure 9] FIG. 2 is a side view of a fender portion of the automobile shown in FIG. [Figure 10] FIG. 10 is a perspective view of a fender liner of the fender portion shown in FIG. 9. [Figure 11] FIG. 2 is a perspective view of the trunk of the automobile shown in FIG. [Figure 12] FIG. 12 is a plan view of the trunk trim of the trunk portion shown in FIG. [Figure 13] FIG. 12 is a side view of the trunk side of the trunk part shown in FIG. [Figure 14]FIG. 1A is a perspective view of a modified example of the soundproof structure of the first embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA thereof. [Figure 15] FIG. 10(A) is a perspective view of a soundproof structure according to a second embodiment of the present invention, and FIG. 10(B) is a cross-sectional view taken along line AA thereof. [Figure 16] FIG. 1(A) is a plan view schematically showing one section of a soundproof structure of the present invention, and FIG. 1(B) is a plan view schematically showing a plurality of sections. [Figure 17] FIG. 1(A) is a plan view schematically showing one section of another example of a soundproof structure of the present invention, and FIG. 1(B) is a plan view schematically showing a plurality of sections. [Figure 18] Graphs (A) to (C) show the sound insulation properties of Examples 1 to 4 of the present invention and Comparative Examples 1 to 4. [Figure 19] Graphs (A) to (C) show the sound insulation properties of Examples 1 and 5 to 8 of the present invention and Comparative Example 3. [Figure 20] Graphs (A) to (C) show the sound insulation properties of Examples 8 to 11 of the present invention. [Figure 21] Graphs (A) and (B) show the sound insulation properties of Examples 1 and 12 to 14 of the present invention and Comparative Examples 5 and 6. [Figure 22] 3A is a perspective view of a soundproof structure according to a third embodiment of the present invention, and FIG. 3B is a cross-sectional view taken along line AA thereof. [Figure 23] 6A is a perspective view of a soundproof structure according to a sixth embodiment of the present invention, and FIG. 6B is a cross-sectional view taken along line AA thereof. [Figure 24] FIG. 13 is a cross-sectional view of a soundproof structure according to a tenth embodiment of the present invention. [Figure 25] 11(A) is a perspective view of a soundproof structure according to an eleventh embodiment of the present invention, and FIG. 11(B) is a cross-sectional view taken along line BB thereof. [Figure 26] 1A is a perspective view of the soundproof structure of Comparative Example 3, and FIG. 1B is a cross-sectional view taken along line AA thereof. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [First embodiment] FIG. 1 is a side view of an automobile 10 equipped with a soundproof structure 1 according to a first embodiment of the present invention; FIG. 2(A) is a perspective view from the front; and FIG. 2(B) is a perspective view from the rear. In this embodiment, soundproof structures 1 are disposed on a roof 10a of the automobile 10, pillars (supports) 10b and 10c supporting the roof 10a, a door 10d, fenders 10e and 10f partially covering tires 11 and 12, respectively, and a trunk 10g. The soundproof structure 1 has a soundproof structure 1a. As shown in FIGS. 3 and 4, the entire soundproof structure 1 may be composed of the soundproof structure 1a, or as shown in FIGS. 5 and 6, the soundproof structure 1 may be composed of the soundproof structure 1a and a soundproof plate-shaped portion 1b. The automobile 10 may be an engine vehicle, an electric vehicle, a fuel cell vehicle, a hybrid vehicle, or the like.

[0027] 3 and 4 show the detailed structure of an example of a soundproof structure 1. FIG. 3(A) is a perspective view of the soundproof structure 1, and FIG. 3(B) is a cross-sectional view taken along line AA in FIG. 3(A) and inverted. FIG. 4(A) is an exploded perspective view of one section of the soundproof structure 1 shown in FIG. 3, and FIG. 4(B) is an exploded front view thereof. This soundproof structure 1 consists only of a soundproof structure portion. However, the soundproof structure portion 1a of a soundproof structure 1 (see FIGS. 5 and 6), which will be described later and which is composed of a soundproof structure portion 1a and a soundproof plate-shaped portion 1b, also has the same structure as that shown in FIGS. 3 and 4. Therefore, in the drawings, the reference numeral "1" indicating the soundproof structure is written alongside the reference numeral "1a" indicating the soundproof structure portion. The soundproof structure 1 shown in FIGS. 3 and 4 includes an elastic sheet-like film portion 2, an elastic support wall portion 3 standing substantially perpendicular to the film portion 2, and a weight portion 4 standing substantially perpendicular to the film portion 2. The soundproof structure 1 is formed by providing a support wall 3 and a weight 4 on a membrane 2. The membrane 2 is divided into multiple compartments (unit structures) 5 by the support wall 3. A weight 4 is located inside each of the multiple compartments 5, or inside some of the multiple compartments 5. Each compartment 5 with a weight 4 located therein has one weight 4 located therein. The height H1 of the support wall 3 extending from the membrane 2 in a direction perpendicular to the membrane 2 is greater than the height H2 of the weight 4 extending from the membrane 2 in a direction perpendicular to the membrane 2. Each weight 4 constitutes a spring-mass resonator having an elastic spring 4a and a mass 4b having a greater mass than the spring 4a. Elasticity here refers to the property of a solid material that has been deformed by an external force and returns to its original shape when the external force is removed, and includes energy elasticity and rubber elasticity (entropy elasticity). Here, the term "having elasticity" refers to the case where the material has at least one of energy elasticity and rubber elasticity (entropy elasticity).

[0028] The support wall 3 of the soundproof structure 1 of this embodiment includes a plurality of first walls 3a extending in a first direction D1 parallel to the membrane 2 and a plurality of second walls 3b extending in a second direction D2 perpendicular to the first direction D1. Specifically, the plurality of first walls 3a are arranged in parallel, and the plurality of second walls 3b are arranged in parallel, with the first walls 3a and the second walls 3b being integrated at their intersections. The plurality of first walls 3a and the plurality of second walls 3b thus form a lattice structure, and a plurality of compartments 5, each having a square planar shape and partitioned by the first walls 3a and the second walls 3b, are arranged in a matrix. In other words, the support wall 3 has a structure in which a plurality of rectangular tubes, each with a square cross section, are arranged side by side, defining each compartment 5. The support wall 3 is preferably made of a flexible material such as rubber, elastomer, or resin foam. The flexible material referred to here is any of a material that has rubber elasticity but not energy elasticity, a material that has energy elasticity but not rubber elasticity, and a material that has both rubber elasticity and energy elasticity.

[0029] In this embodiment, the portion of the weight portion 4 attached to the membrane portion 2 is the spring portion 4a, and the portion opposite to the side attached to the membrane portion 2 is the mass portion 4b, which has a larger mass than the spring portion 4a. In the example shown in Figures 3 and 4, the spring portion 4a and the mass portion 4b have the same shape and dimensions but are made of different materials. The spring portion 4a is made of a flexible material, and the mass portion 4b is made of a material with a higher density than the material constituting the spring portion 4a. A spring-mass resonator is constructed in which the spring portion 4a functions as a spring and the mass portion 4b functions as a mass. Note that in addition to the spring portion 4a of the weight portion 4, the membrane portion 2 may also function as part of the spring of the spring-mass resonator. Furthermore, the air in the space surrounded by the membrane portion 2 and the support wall portion 3 may function as part of the spring of the spring-mass resonator (an air spring). It is preferable that the spring portion 4a is also made of a flexible material, i.e., a material that has rubber elasticity but not energy elasticity, a material that has energy elasticity but not rubber elasticity, or a material that has both rubber elasticity and energy elasticity.

[0030] In the soundproof structure 1 of this embodiment, the vibration of the film 2 is controlled by the action of a spring-mass resonator formed by the spring portion 4a and mass portion 4b of the weight portion 4. In particular, in a specific frequency range (for example, frequencies below 1000 Hz, which are the main frequency bands of road noise and tire pattern noise in automobiles), the film vibration is significantly reduced, resulting in a reduction in the sound radiated from the film 2 and a high level of sound insulation.

[0031] The section 5 of the soundproof structure 1 of this embodiment has a membrane part 2 with an area of ​​1000 cm 2 Preferably, 10 to 1000 compartments are provided per 1000 cm2 of the membrane part 2, and more preferably, 50 to 500 compartments are provided per 1000 cm2 of the membrane part 2. 2 By having 10 or more per unit area, the entire soundproof structure 1 can be divided into multiple sections 5, and each section can have its own soundproofing effect, thereby improving the sound insulation of the entire soundproof structure 1. In addition, if the section 5 is 2 By limiting the number of pieces to 1,000 or less per section, the increase in the weight of the entire soundproof structure 1 can be suppressed. 2 More than 1000mm 2 Preferably, it is less than 200 mm 2 Over 800mm 2 It is more preferable that the area of ​​the planar shape of each of the sections 5 is 100 mm or less. 2 Therefore, it is easy to arrange the weight part 4 inside, and on the other hand, the area is 1000 mm 2or less, the effect of the weight portion 4 on the membrane portion 2 is large, resulting in high sound insulation. The height of the entire soundproof structure 1 in the direction perpendicular to the membrane portion 2 is preferably 5 mm or more and 20 mm or less. When the height of the entire soundproof structure 1 is 5 mm or more, the weight portion 4 can have a sufficient height as a spring-mass resonator, and when the height is 20 mm or less, an increase in the weight of the entire soundproof structure 1 is suppressed. Note that each drawing shows each compartment 5 and supporting wall portion 3, etc., schematically, and the number and area of ​​compartments 5 and the height of supporting wall portion 3 may not be shown strictly accurately or may not be consistent across drawings, but it is preferable that the number and area of ​​compartments 5 and the height of supporting wall portion 3 are appropriately designed to be within the aforementioned numerical ranges.

[0032] The film portion 2, supporting wall portion 3, and spring portion 4a of the soundproof structure 1 of this embodiment are all made of an elastic body having a dynamic storage modulus (E') of 0.01 MPa to 100 MPa at 23° C. and a frequency of 1 Hz to 1000 Hz, and a loss tangent (tanδ) of 0.01 to 0.50 at 23° C. and a frequency of 1 Hz to 1000 Hz, preferably 0.05 MPa to 50 MPa at 23° C. and a loss tangent (tanδ) of 0.05 to 0.50 at 23° C. The dynamic storage modulus (E') and loss tangent (tanδ) are determined by creating a master curve based on 23° C. using a dynamic viscoelasticity tester. Since the dynamic storage modulus (E') at 23°C in the frequency range of 1 Hz to 1000 Hz is 0.01 MPa or more, sound insulation in the target frequency band is good, and the shape retention of the film 2 and the supporting wall 3 is good. Since the dynamic storage modulus (E') at 23°C in the frequency range of 1 Hz to 1000 Hz is 100 MPa or less, sound insulation in the target frequency band is good, and the soundproof structure 1 does not become rigid, making it easy to install. The film 2 and the supporting wall 3 may be made of the same material or different materials. It is preferable that the film 2 is also made of a flexible material, i.e., a material that has rubber elasticity but no energy elasticity, a material that has energy elasticity but no rubber elasticity, or a material that has both rubber elasticity and energy elasticity.

[0033] Since the weight portion 4 is attached to the film portion 2, it is preferable that the film portion 2 be a hard elastic film. The dynamic storage modulus (E') of the film portion 2 is preferably 15 MPa or more, and the thickness (film thickness) is preferably 0.1 mm to 3.0 mm, more preferably approximately 0.5 mm. When the film portion 2 is 0.1 mm or more, sufficient thickness is ensured, making it easy to handle. When the film portion 2 is 3.0 mm or less, an increase in the overall thickness and weight of the soundproof structure 1 is suppressed, and the entire soundproof structure 1 does not become too hard, making it easy to install. The material of the film portion 2 preferably has a durometer A hardness according to JIS K6253 of 50 or more, more preferably 70 or more. By setting the durometer A hardness of the film portion 2 within the above range, deterioration of the vibration of the film portion 2 is prevented, and sound insulation in the frequency band to be sound-insulated is improved. The rigidity (axial rigidity) k of the membrane part 2 is expressed as k = E' × A / L using the dynamic storage modulus E', the cross-sectional area A of the membrane part 2, and the thickness L of the membrane part 2. When the area of ​​the membrane part 2 to be evaluated for rigidity is 1000 cm 2 When the stiffness k is 10 6 N / mm or more 10 9 N / mm or less is preferable, and 3×10 6 N / mm or more 10 8 It is more preferable that the surface area of ​​the film portion 2 is 1000 cm or less. 2 When the stiffness is 10 6 When the surface area of ​​the film 2 is 1000 cm or more, the deterioration of the vibration of the film 2 can be suppressed, and the sound insulation performance in the frequency band to be insulated can be improved. 2 When the stiffness is 10 9 N / mm or less, the soundproof structure 1 becomes flexible and easy to install. The bending rigidity K of the film 2 is expressed as K=E'×I from the dynamic storage modulus E' and the second moment of area I, and the second moment of area I is expressed as I=b×h from the thickness h of the film 2 and the width b of the film 2. 3 When the area of ​​the membrane part 2 to be evaluated is 1000 cm 2 When the bending stiffness K is 1N / mm 2 Over 10 5 N / mm2 Preferably, it is 10 N / mm or less. 2 5x10 or more 4 N / mm 2 It is more preferable that the area of ​​the membrane portion 2 is 1000 cm or less. 2 When the bending stiffness K is 1N / mm 2 By satisfying the above, the vibration of the film part 2 is improved, and it is possible to suppress deterioration of the sound insulation performance in the frequency band to be insulated. 2 When the bending stiffness K is 10 5 N / mm 2 The following makes the soundproof structure 1 flexible and improves installation properties. The cross-sectional shape of the film portion 2 is not particularly limited, and may be flat or may have irregularities.

[0034] Materials for the film portion 2 include cross-linked (vulcanized) rubber, thermoplastic elastomer, and plastic. Examples of 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-α-olefin-non-conjugated polyene copolymers such as ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), and ethylene-butene-diene rubber (EBDM), 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 methylvinylsilicone rubber (VMQ) and fluorinated silicone rubber (FVMQ), urethane rubber (U), and fluororubber (FKM). These crosslinked (vulcanized) rubbers can be used alone or in combination of two or more. Examples of crosslinking (vulcanization) methods include a method of crosslinking (vulcanization) by heating using a crosslinking agent (vulcanizing agent) such as an organic peroxide, a phenolic resin, an oxime compound, sulfur, a sulfur-based compound, or a polyamine compound, or a method of crosslinking by irradiation with an electron beam. The crosslinked (vulcanized) rubber may contain various known compounding agents commonly used as rubber compounding agents (reinforcing agents such as carbon black and silica, fillers such as calcium carbonate, softeners such as paraffin oil and plasticizers, processing aids, antioxidants, light stabilizers, flame retardants, mildew inhibitors, acid acceptors, silane coupling agents, antistatic agents, ultraviolet absorbers, etc.). These crosslinked (vulcanized) rubbers, crosslinking agents (vulcanizing agents), and compounding agents may be made from biomass raw materials.

[0035] Examples of thermoplastic elastomers 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 thermoplastic polyurethanes. Examples of plastics include polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, and composite resins containing these. These thermoplastic elastomers and plastics may be made from biomass raw materials.

[0036] Specifically, the material of the film portion 2 is preferably ethylene-propylene-diene rubber, thermoplastic olefin-based elastomer, thermoplastic styrene-based elastomer, polyethylene, polypropylene, polyethylene terephthalate, thermoplastic polyurethane, or the like.

[0037] The support wall 3 is preferably made of a flexible material that is soft enough to support the membrane 2. The thickness of the support wall 3 is preferably 0.5 mm to 5.0 mm, and more preferably 1.0 mm to 3.0 mm. When the thickness of the support wall 3 is 0.5 mm or more, the shape retention of the soundproof structure 1 is improved. When the thickness of the support wall 3 is 5.0 mm or less, the vibration of the membrane 2 is improved, sound insulation in the frequency band to be insulated is improved, and an increase in the weight of the entire soundproof structure 1 can be suppressed. The height of the support wall 3 extending in a direction perpendicular to the membrane 2 is preferably 5 mm to 20 mm, and more preferably 10 mm to 20 mm. The height of the support wall 3 may vary partially. When the height of the support wall 3 varies partially, the higher part may be 10 mm to 20 mm, more preferably 12 mm to 20 mm, and even more preferably 14 mm to 20 mm. By ensuring that the height of the support wall 3 is not too low, the weight 4 can have a sufficient height as a spring-mass resonator. By ensuring that the height of the support wall 3 is not too high, the overall weight can be reduced. The material of the support wall 3 preferably has a durometer A hardness according to JIS K6253 of 1 or more and 90 or less, more preferably 10 or more and 70 or less. By ensuring that the durometer A hardness of the support wall 3 is 1 or more, the shape retention of the soundproof structure 1 can be maintained. By ensuring that the durometer A hardness of the support wall 3 is 90 or less, vibrations from the support wall 3 can be prevented from being transmitted to the membrane 2, which would deteriorate the soundproofing performance. Therefore, the soundproof structure 1 becomes flexible and easy to install. The stiffness k of the support wall 3 is expressed as k = E' × A / L, where E' is the dynamic storage modulus of elasticity, A is the cross-sectional area of ​​the support wall 3, and L is the height of the support wall 3. When the area of ​​the support wall 3 to be evaluated for stiffness is 1000 cm, the stiffness k is calculated as k = E' × A / L. 2 When the stiffness k is 10N / mm or more, 6 N / mm or less is preferable, and 10 2 N / mm or more 10 5 It is more preferable that the area of ​​the support wall 3 is 1000 cm or less. 2When the area of ​​the support wall 3 is 1000 cm, the stiffness k is 10 N / mm or more, so that the shape of the soundproof structure 1 can be maintained. 2 When the stiffness k is 10 6 By keeping the resistance at N / mm or less, vibrations from the support wall 3 are prevented from being transmitted to the film 2, which would deteriorate the sound insulation performance, and the soundproof structure 1 does not become rigid, making it easy to install.

[0038] Examples of materials for the support wall portion 3 include cross-linked (vulcanized) rubber, thermoplastic elastomers, and resin foams. The cross-linked (vulcanized) rubber and thermoplastic elastomers may be the same as those listed as materials for the membrane portion 2. The resin foams may have either a closed-cell structure or an open-cell structure, and examples include polyurethane foam, polystyrene foam, polyethylene foam, and ethylene-vinyl acetate rubber (EVA) foam. Specifically, the materials for the support wall portion 3 are preferably ethylene-propylene-diene rubber, urethane rubber, silicone rubber, thermoplastic olefin-based elastomers, thermoplastic styrene-based elastomers, thermoplastic polyurethane, and polyurethane foam. These resin foams may be made from biomass materials.

[0039] The material of the spring portion 4a of the weight portion 4 is a flexible material such as cross-linked (vulcanized) rubber, thermoplastic elastomer, or resin foam. The cross-linked (vulcanized) rubber, thermoplastic elastomer, or resin foam may be the same as the materials listed as the materials 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, or polyurethane foam. These materials may be made from biomass raw materials.

[0040] The material of the mass portion 4b is not particularly limited, but it may be made of resin, metal, or the like, and the mass portion 4b has a larger mass than the spring portion 4a, for example, a mass of 0.1 g or more and 2.0 g or less. The mass portion 4b preferably has a mass at least twice the mass of the spring portion 4a. By making the weight of the mass portion 4b at least twice the mass of the spring portion 4a, the weight portion 4 can be made to resonate sufficiently in the frequency range to be sound-insulated, thereby achieving a good sound-insulating effect. When the material of the mass portion 4b is resin, the resin may be made from a biomass material.

[0041] The spring constant (rigidity) of the spring portion 4a is determined based on the mass of the mass portion 4b so that the resonant frequency coincides with the frequency that is the main target of sound insulation. For example, if the mass of the mass portion 4b is 1.0 g and the main target frequency of sound insulation 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.

[0042] With this configuration, the film portion 2, the support wall portion 3, and the weight portion 4 are all relatively light in weight, and the dimensions in the direction perpendicular to the film portion 2 are relatively small. As described above, the soundproof structure 1 of this embodiment is lightweight and thin, yet provides high sound insulation in a specific frequency range (for example, frequencies below 1000 Hz, which are the main frequency bands of road noise and tire pattern noise in automobiles) as described above. Furthermore, the support wall portion 3 made of a flexible material can be easily and stably installed on a flat member or a member with a curved or uneven surface, without being fixed by adhesive or the like.

[0043] 5 and 6 are cross-sectional views of a soundproof structure 1 consisting of a soundproof structural member 1a and a soundproof plate-like member 1b. In the example shown in FIGS. 5 and 6, the soundproof structure 1 is configured such that a large-area soundproof plate-like member 1b and two soundproof structural members 1a located on either side of it are integrally formed or joined together so that they can be handled as a single component. In the configuration shown in FIG. 5, the soundproof plate-like member 1b and the two soundproof structural members 1a of the soundproof structure 1 are positioned side by side in a plane. However, as in the modified example shown in FIG. 6, two soundproof structural members 1a may be stacked on the soundproof plate-like member 1b. The soundproof structural member 1a has the same configuration as the soundproof structure 1 shown in FIGS. 3 and 4, and therefore a description thereof will be omitted. In this soundproof structure 1, the soundproof structural member 1a is disposed in a portion of the automobile 10 where sound propagation is particularly strong. For example, sound-insulating structural parts 1a are arranged at two locations close to tires 11 and 12, which are areas where road noise and tire pattern noise are largely propagated, and sound-insulating plate-shaped parts 1b are arranged between the sound-insulating structural parts 1a and at a position away from the tires 11 and 12.

[0044] The soundproofing plate-like portion 1b may be made of a material similar to existing soundproofing materials, such as a single-layer structure consisting of a layer of sound-absorbing material (e.g., felt, polyurethane foam, or glass wool) and a layer of sound-insulating material (e.g., resin film or rubber sheet), or a laminated structure of these. These materials may be made from biomass materials. The soundproofing plate-like portion 1b is a plate-like member and may have different thicknesses depending on the portion. For example, the soundproofing plate-like portion 1b may have thicknesses ranging from thin portions less than 5 mm to thick portions approximately 40 mm. If the large-area soundproofing structure 1 were composed only of soundproofing structures, it would have a high soundproofing effect, but the soundproofing structure 1 would be heavy and may adversely affect the performance of the automobile 10. In contrast, the large-area soundproofing structure 1 has soundproofing structures 1a with high soundproofing effect located in positions where sound propagation is particularly strong (e.g., positions facing the tires 11 and 12). This allows for efficient sound penetration while minimizing weight gain. Furthermore, the soundproof structure 1 can be easily and stably installed on components of various shapes without the need for fixing by adhesive or the like. Therefore, the soundproof structure 1 of this embodiment can be stacked on components of complex shapes and stably held in place. If the soundproof structure 1 is integrated with an existing component, the number of parts does not increase and installation is simple. Methods for incorporating the soundproof structure 1 into an existing component include ultrasonic welding, adhesion with a hot melt adhesive, fixing with clips, bolts, rivets, etc., and insert molding.

[0045] In this embodiment, the soundproofing structure 1 having the above-described configuration is disposed on at least a portion of a member that partially separates the passenger compartment 13 of the automobile 10 from the outside of the vehicle. In the example shown in FIGS. 1 and 2, the soundproofing structure 1 is disposed on the roof portion 10a, pillar portions 10b and 10c, door portion 10d, fender portions 10e and 10f, and trunk portion 10g of the automobile 10. As shown in FIG. 7, which is an enlarged view of a portion of FIG. 1, the soundproofing structure 1 having the above-described configuration (see FIGS. 3 and 4) is disposed inside the roof portion 10a of the automobile 10. This can suppress the intrusion of noise into the passenger compartment 13 from above the automobile. Furthermore, the pillar portions 10b and 10c are each hollow cylindrical or rectangular tubular, and the soundproofing structure 1 is embedded therein. This suppresses the intrusion of noise into the passenger compartment 13 from around the windows of the automobile 10. While FIG. 7 shows the rear pillar portion 10c, a soundproofing structure 1 is also disposed on the front pillar portion 10b.

[0046] 8 is a perspective view showing the inside of a door portion 10d of an automobile 10. Inside the door portion 10d, the soundproofing structure 1 having the above-described configuration (see FIGS. 3 and 4) is disposed on the door trim 14. This soundproofing structure 1 prevents noise from entering the vehicle interior 13 through the door portion 10d.

[0047] Fig. 9 is a side view showing a main portion of one fender portion 10e of an automobile 10, and Fig. 10 is a perspective view showing the fender liner 15 thereof. A soundproofing structure 1 having the above-described configuration (see Figs. 3 and 4) is disposed on the fender liner 15 on the passenger compartment 13 side. This soundproofing structure 1 prevents noise from entering the passenger compartment 13 from the tire 11. Although not shown in Figs. 9 and 10, a soundproofing structure 1 of this embodiment is also disposed on the other fender portion 10f on the passenger compartment 13 side of the fender liner 15. These soundproofing structures 1 prevent noise (road noise and tire pattern noise) from entering the passenger compartment 13 from the tires 11 and 12 that contact the ground.

[0048] FIG. 11 is a perspective view showing the interior of a trunk section 10g of an automobile 10. FIG. 12 is a plan view of a trunk trim 16 of the trunk section 10g. This trunk trim 16 is configured by laminating a felt sheet material and a thermoplastic resin plate member (not shown), and the soundproof structure 1 having the above-described configuration (see FIGS. 3 and 4) is disposed therein. Alternatively, similar to the configuration shown in FIGS. 5 and 6, the trunk trim 16 may be configured by laminating a soundproof structure 1 having a thermoplastic resin soundproof plate-like portion 1b and a soundproof structure portion 1a integrated together on a felt sheet material (not shown). Although not shown in FIG. 11, trunk sides 17 are disposed on both sides of the interior of the trunk section 10g. These trunk sides 17 are shown in FIG. 13. The soundproof structure 1 of this embodiment is disposed on the trunk sides 17. Therefore, soundproofing structures 1 are arranged in at least three locations inside the trunk section 10g, preventing noise from the trunk section 10g and noise transmitted from the outside through the trunk section 10g from entering the passenger compartment 13.

[0049] As explained above, in the example shown in Figures 1 to 13, soundproofing structures 1 are arranged in the roof portion 10a, pillar portions 10b and 10c, door portions 10d, fender portions 10e and 10f, and trunk portion 10g of the automobile 10, thereby suppressing the intrusion of noise into the passenger compartment 13 from all directions around the automobile 10. This makes it possible to keep the passenger compartment 13 quiet. However, not all of these soundproofing structures 1 are essential. As long as the soundproofing structures 1 of this embodiment are arranged in at least some of the members that partially separate the passenger compartment 13 of the automobile 10 from the outside of the vehicle, a certain degree of effect in keeping the passenger compartment 13 quiet can be achieved, and this is therefore included in the present invention. Furthermore, even if the soundproofing structure 1 is arranged in a location other than the roof portion 10a, pillar portions 10b, 10c, door portions 10d, fender portions 10e, 10f, and trunk portion 10g of the automobile 10, a certain degree of effect can be obtained as long as the soundproofing structure 1 is arranged in at least a part of a member that partially separates the passenger compartment 13 from the outside of the vehicle, and this is still included in the present invention. Since the members located outside the passenger compartment 13 of the automobile 10 are generally located between the space outside the vehicle and the passenger compartment 13, they directly or indirectly separate the passenger compartment 13 from the space outside the vehicle, and can be said to be members that partially separate the passenger compartment 13 of the automobile 10 from the outside of the vehicle. Note that the soundproofing structures 1 in each location may be exposed, or may be covered by a panel or sheet (not shown).

[0050] The soundproof structure 1 of this embodiment may be attached to existing components such as a panel (not shown) in the roof portion 10a, the inside of the pillar portions 10b and 10c, the door trim 14, the fender liner 15, the trunk trim 16, or the trunk side 17, or may be provided as part of these existing components. When the soundproof structure 1 is provided as part of an existing component, the soundproof structure 1 may be composed of a sound-insulating structural portion 1a and a soundproof plate-shaped portion 1b (see FIGS. 5 and 6). The soundproof structure 1 may also be installed independently without being attached to a component such as a panel.

[0051] In this embodiment, the lightweight and thin soundproof structure 1 provides high sound insulation in a specific frequency range (for example, frequencies below 1000 Hz, which are the main frequency bands for road noise and tire pattern noise in automobiles), and also provides good installation without the need for adhesive. In particular, it can efficiently block noise from all directions outside the automobile 10 from entering the passenger compartment 13, providing a great soundproofing effect.

[0052] The specific structure of the soundproof structure 1 of this embodiment is not limited to the configuration shown in FIGS. 3 and 4 . Modifications of the soundproof structure 1 will be described below. FIG. 14(A) is a perspective view showing a modification of the soundproof structure 1 of the present invention, and FIG. 14(B) is a cross-sectional view taken along line AA in FIG. 14(A) and inverted upside down. In this modification, the spring portion 4a and the mass portion 4b of the weight portion 4 of the soundproof structure 1a have different shapes and dimensions. The spring portion 4a is cylindrical with a small diameter, and the mass portion 4b is cylindrical with a large diameter. Although not shown, the spring portion 4a may be cylindrical with a longer diameter, and the mass portion 4b may be spherical. In this case, 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 these examples, 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 made of the same material, the mass portion 4b can have a greater mass than the spring portion 4a, thereby forming a spring-mass resonator. However, in this example, the spring portion 4a and the mass portion 4b may be made of different materials, with the mass portion 4b having a greater mass than the spring portion. Alternatively, the spring portion 4a may be truncated cone-shaped, the mass portion 4b may be cylindrical, and the diameter of the smallest part of the truncated cone-shaped spring portion 4a may be substantially the same as the diameter of the cylindrical mass portion 4b. In this example, the spring portion 4a has a larger volume than the mass portion 4b. In this case, the mass portion 4b is made of a material with a higher density than the spring portion 4a, and the mass portion 4b has a greater mass than the spring portion, thereby forming a spring-mass resonator. If the spring portion 4a has a truncated cone-shaped shape tapering away from the membrane portion 2, it can be easily releasable from a mold when the membrane portion 2 and the spring portion 4a are integrally molded. The shape and dimensions of the weight portion 4 of the present invention are not limited, and various shapes not shown, including the shapes shown in Figures 3 to 4 and 14, can be adopted. The weight portion 4 is formed in any shape and dimensions selected so as to satisfy the performance of the spring mass resonator required for sound insulation and to be able to be housed within the compartment 5.

[0053] In the soundproof structure 1 of this embodiment, the spring portion 4a and the mass portion 4b of the weight portion 4 are made of different materials and / or different volumes. This allows the mass portion 4b to be larger than the spring portion 4a, forming a spring-mass resonator and achieving a sufficient sound-insulating effect. That is, the materials, shapes, and dimensions of the spring portion 4a and the mass portion 4b are determined to form a spring-mass resonator that can provide a sufficient sound-insulating effect. The materials, shapes, and dimensions of the spring portion 4a and the mass portion 4b can be freely selected as long as the mass of the mass portion 4b is larger than the spring portion 4a to the extent that a spring-mass resonator that can provide a sufficient sound-insulating effect can be formed. However, the spring portion 4a must be made of a flexible material to function as a spring. The above-described configuration examples can also be used as the sound-insulating structure portion 1a of a soundproof structure 1 that includes a sound-insulating structure portion 1a and a sound-insulating plate portion 1b, as shown in FIGS. 5 and 6 .

[0054] [Second embodiment] FIG. 15(A) is a perspective view showing a soundproof structure 1 according to a second embodiment of the present invention, and FIG. 15(B) is a cross-sectional view taken along line AA in FIG. 15(A) and inverted. The soundproof structure 1 of this embodiment has a weight portion 7 of a single structure that is not divided into a spring portion and a mass portion. In this soundproof structure 1, the entire weight portion 7 functions as the mass portion, and a spring-mass resonator is configured in which the membrane portion 2 functions as the spring portion. As an example, the mass of the weight portion 7 is approximately 0.1 g to 2.0 g. The material of the weight portion 7 is not limited, and it may be formed from, for example, synthetic resin or metal. The rest of the configuration is the same as in the first embodiment described above, so a description thereof will be omitted. In the soundproof structure 1 of this embodiment, membrane vibration is also controlled by the action of the spring-mass resonator configured by the weight portion 7 and the membrane portion 2. This significantly reduces membrane vibration in a specific frequency range (for example, below 1000 Hz), thereby providing high sound insulation. In addition, together with the membrane portion 2, the air in the space surrounded by the membrane portion 2 and the support wall portion 3 may function as part of the spring (air spring) of the spring mass resonator.

[0055] In both the membrane part 2 and the supporting wall part 3 of this embodiment, it is preferable that the dynamic storage modulus at 23° C. and at a frequency of 1 Hz to 1000 Hz is 0.01 MPa or more and 100 MPa or less, and the loss tangent at 23° C. and at a frequency of 1 Hz to 1000 Hz is 0.01 or more and 0.50 or less. Furthermore, it is more preferable that the membrane part 2 and the supporting wall part 3 of this modified example have a dynamic storage modulus (E') at 23° C. and at a frequency of 1 Hz to 1000 Hz of 0.05 MPa or more and 50 MPa or less, and a loss tangent (tanδ) at 23° C. and at a frequency of 1 Hz to 1000 Hz of 0.05 or more and 0.50 or less.

[0056] The support wall 3 of this embodiment is made of any one of a material that has rubber elasticity but not energy elasticity, a material that has energy elasticity but not rubber elasticity, and a material that has both rubber elasticity and energy elasticity. Similarly, the membrane 2 of this embodiment is made of any one of a material that has rubber elasticity but not energy elasticity, a material that has energy elasticity but not rubber elasticity, and a material that has both rubber elasticity and energy elasticity.

[0057] Although not shown, as a modified example of the soundproof structure 1 of this embodiment, the weight portion 7 can be configured to have a truncated cone shape that tapers in the direction away from the film portion 2. This configuration allows for good releasability from a mold when the film portion 2 and the weight portion 7 are integrally molded. In this embodiment, the shape of the weight portion 7 can be determined arbitrarily and is not particularly limited. The configuration of this embodiment can also be used as the soundproof structure portion 1a of a soundproof structure 1 consisting of a soundproof structure portion 1a and a soundproof plate-shaped portion 1b, as shown in Figures 5 and 6.

[0058] In the soundproof structure 1 of any of the first and second embodiments described above, the film portion 2 and the support wall portion 3 can be formed by integral molding or two-color molding using the above-mentioned materials, such as injection molding, compression molding, press molding, extrusion molding, transfer molding, or cast molding. Furthermore, at least a portion of the weight portions 4, 7 can also be formed together with the film portion 2 and the support wall portion 3 by integral molding, two-color molding, or insert molding using the above-mentioned materials. However, the soundproof structure 1 may also be assembled by forming the film portion 2, the support wall portion 3, and the weight portions 4, 7 separately and then joining them together by adhesive or heat fusion.

[0059] In the configuration of the soundproof structure 1 described above, as shown in FIGS. 16(A) and 16(B), the support wall 3 includes a plurality of first wall portions 3a extending in a first direction D1 parallel to the membrane portion 2 and a plurality of second wall portions 3b extending in a second direction D2 perpendicular to the first direction D1, and the planar shape of each compartment 5 is square. In other words, the support wall 3 is a rectangular tube having a square cross-section that defines each compartment 5, and a large number of rectangular support wall portions 3 are arranged side by side, and the support wall portions 3 of adjacent compartments 5 are integrated. However, this configuration is not limited to this. For example, although not shown, the planar shape of each compartment 5 may be triangular, and the support wall 3 may be a rectangular tube having a triangular cross-section that defines each compartment 5. Furthermore, although not shown, the planar shape of each compartment 5 may be pentagonal, and the support wall 3 may be a rectangular tube having a pentagonal cross-section that defines each compartment 5. As shown in Figures 17(A) and 17(B), the planar shape of each compartment 5 may be hexagonal, and the support wall 3 may be a rectangular tube with a hexagonal cross-section that defines each compartment 5, forming a so-called honeycomb structure. Furthermore, although not shown, the planar shape of each compartment 5 may be circular, and the support wall 3 may be a cylinder with a circular cross-section that defines each compartment 5. When the planar shape of each compartment 5 is pentagonal or circular, gaps will form between the compartments 5. Therefore, it is preferable to determine the shape and dimensions of the support wall 3 so as to minimize these gaps, and it is preferable that the membrane 2 expand to fill these gaps. When the planar shape of each compartment 5 is triangular, quadrangular, or hexagonal, no gaps will form between the compartments 5. Furthermore, each compartment 5 may have various shapes (not shown), such as a rectangle, parallelogram, trapezoid, polygon with seven or more sides, ellipse, oval, etc., or may be irregular. The support wall portion 3 is formed to have a shape and dimensions that match the planar shape of each compartment 5.

[0060] The soundproof structure 1 of the present invention is thin and lightweight, and can be stably used when placed on a curved or uneven surface such as an automobile panel (for example, a panel (not shown) within the roof portion 10a, the inner surfaces of the pillar portions 10b and 10c, the door trim 14, the fender liner 15, the trunk trim 16, the trunk side 17, etc.). These members are basically non-porous plates, and examples thereof include metal plates (iron plates, steel plates, and aluminum plates) and resin plates. When the member on which the soundproof structure 1 is placed is a metal plate, its thickness is preferably in the range of 0.5 mm to 2.0 mm. When the member is a resin plate, its thickness is preferably in the range of 0.5 mm to 20 mm. It is preferable that the end face of the support wall portion 3 of the soundproof structure 1 opposite the side attached to the film portion 2 is placed on a member such as a panel. In this case, the support wall portion 3 of the soundproof structure 1 and the member such as a panel may or may not be bonded to each other. However, it is preferable that the support wall portion 3 is placed on the member such as a panel without being bonded to the member such as a panel. However, the soundproof structure 1 can also be installed independently without being placed on a member such as a panel. [Example]

[0061] Specific examples and comparative examples of the soundproof structure 1 of the present invention will be described below. [Example 1] The soundproof structure 1 of Example 1 of the present invention has the same structure as the soundproof structure 1 of the first embodiment shown in Figures 3 and 4. The film portion 2 is made of an elastic body having a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at 23°C and at frequencies of 1 Hz to 1000 Hz, and a loss tangent of 0.01 or more and 0.50 or less at 23°C and at frequencies of 1 Hz to 1000 Hz. More specifically, the film part 2 of this example has a dynamic storage modulus (E') of 20.4 MPa and a loss tangent (tanδ) of 0.12 at 23°C and a frequency of 1 Hz, a dynamic storage modulus (E') of 23.0 MPa and a loss tangent (tanδ) of 0.13 at 23°C and a frequency of 10 Hz, a dynamic storage modulus (E') of 25.4 MPa and a loss tangent (tanδ) of 0.16 at 23°C and a frequency of 100 Hz, and a dynamic storage modulus (E') of 28.8 MPa and a loss tangent (tanδ) of 0.14 at 23°C and a frequency of 1000 Hz, a durometer A hardness of 70 according to JIS K6253, and a film thickness of 0.5 mm. The planar shape of this film part 2 has an area of ​​1000 cm. 2 If the square is , the bending stiffness K is 67.2N / mm 2 The planar shape has an area of ​​400 cm 2 If the square is , the bending stiffness K is 42.5N / mm 2 If the same material as the film portion 2 is used, the film thickness is 3 mm, and the plane shape has an area of ​​1000 cm 2 When a square film portion 2 is formed, its bending stiffness K is about 1.5×10 4 N / mm 2 is.

[0062] The support wall portion 3 of this embodiment is made of an elastic body having a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at 23°C and at a frequency of 1 Hz to 1000 Hz, and a loss tangent of 0.01 or more and 0.50 or less at 23°C and at a frequency of 1 Hz to 1000 Hz. More specifically, the support wall 3 of this example has a dynamic storage modulus (E') of 13.2 MPa and a loss tangent (tanδ) of 0.12 at 23°C and a frequency of 1 Hz, a dynamic storage modulus (E') of 15.0 MPa and a loss tangent (tanδ) of 0.14 at 23°C and a frequency of 10 Hz, a dynamic storage modulus (E') of 17.4 MPa and a loss tangent (tanδ) of 0.17 at 23°C and a frequency of 100 Hz, and a dynamic storage modulus (E') of 20.2 MPa and a loss tangent (tanδ) of 0.16 at 23°C and a frequency of 1000 Hz, a durometer A hardness according to JIS K6253 of 65, a plate thickness of 1.6 mm, and a height of 10 mm in the direction perpendicular to the membrane 2. However, only the outermost support wall 3 has a plate thickness of half that, 0.8 mm. The compartments 5 defined by the multiple support walls 3 (first wall 3a and second wall 3b) are square, measuring 25 mm x 25 mm, and there are 49 compartments 5 in the 200 mm x 200 mm square area (evaluation surface) of the membrane 2. However, only a portion of this area is shown schematically in the drawing. The weight 4 is cylindrical, with a diameter of 6 mm and a height (dimension in the direction perpendicular to the membrane 2) of 6 mm.

[0063] Of this weight portion 4, the spring portion 4a, which is the portion attached to the membrane portion 2, is 3 mm high and is made of an elastic body having a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at 23°C and at frequencies of 1 Hz to 1000 Hz, and a loss tangent of 0.01 or more and 0.50 or less at 23°C and at frequencies of 1 Hz to 1000 Hz. More specifically, spring portion 4a in this embodiment has a dynamic storage modulus (E') of 0.60 MPa and a loss tangent (tanδ) of 0.17 at 23°C and a frequency of 1 Hz, a dynamic storage modulus (E') of 0.74 MPa and a loss tangent (tanδ) of 0.24 at 23°C and a frequency of 10 Hz, a dynamic storage modulus (E') of 0.97 MPa and a loss tangent (tanδ) of 0.17 at 23°C and a frequency of 100 Hz, and a dynamic storage modulus (E') of 1.31 MPa and a loss tangent (tanδ) of 0.16 at 23°C and a frequency of 1000 Hz, and is made of silicone rubber with a durometer A hardness of 10 according to JIS K6253. Mass portion 4b, which is the portion of weight portion 4 opposite the side attached to membrane portion 2, also has a height of 3 mm and is made of rigid stainless steel (SUS304). The mass of the weight 4 is approximately 0.8 g, and has a resonance frequency that shows a peak at 600 Hz to 650 Hz in the direction perpendicular to the installation surface of the weight 4. The height of the entire soundproof structure 1 is 10.5 mm, and the overall surface density of one section 5, including the membrane 2, support wall 3, and weight 4, is 2.97 kg / m 2 The surface density is a value calculated from the weight and area of ​​the sample.

[0064] The sound insulation of the soundproof structure 1 of this example was measured with the end face of the support wall 3 opposite to the side attached to the membrane 2 facing the incident sound side. Specifically, in accordance with the intensity method specified in JIS A1441-1, a test facility with a reverberation chamber as the sound source room and a semi-anechoic chamber as the sound receiving room was used to determine the sound transmission loss (transmission loss) [dB] versus the 1 / 3 octave band center frequency [Hz] by 1 / 3 octave band analysis. The relationship between the 1 / 3 octave band center frequency and the sound transmission loss was determined and is shown in Figures 18(A) to 18(C), 19(A) to 19(C), and 21(B). The larger the sound transmission loss, the higher the sound insulation. Note that in the 1 / 3 octave band center frequencies [Hz] shown in Figures 18(A) to 21(B), 1 kHz corresponds to 1000 Hz, and the prefix "k" means 1000.

[0065] [Example 2] The soundproof structure 1 of Example 2 of the present invention has the same structure as the soundproof structure 1 of the second embodiment shown in Fig. 15. 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 having 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 perpendicular to the film portion 2) of 5 mm. The mass of the weight portion 7 is approximately 0.85 g, and the surface density of this configuration is 3.04 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0066] [Example 3] The soundproof structure 1 of Example 3 of the present invention shown in Figure 22 has the same structure as Example 2, but has a weight 7 that is smaller than the weight 7 of Example 2. Figure 22(A) is a perspective view of the soundproof structure 1, and Figure 22(B) is a cross-sectional view taken along line AA and turned upside down. The film 2 and supporting wall 3 of this example are the same as the film 2 and supporting wall 3 of Example 1. The weight 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 perpendicular to the film 2) of 5 mm. The mass of the weight 7 is approximately 0.15 g. The surface density of this configuration is 2.54 kg / m2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0067] [Example 4] A soundproof structure 1 (not shown) of Example 4 of the present invention has the same structure as 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 weight portion 4 of this example are the same as the film portion 2 and 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 of 0.01 MPa or more and 100 MPa or less at 23°C and at frequencies of 1 Hz to 1000 Hz, and a loss tangent of 0.01 or more and 0.50 or less at 23°C and at frequencies of 1 Hz to 1000 Hz. 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 23°C and a frequency of 1 Hz, a dynamic storage modulus (E') of 1.72 MPa and a loss tangent (tanδ) of 0.12 at 23°C and a frequency of 10 Hz, a dynamic storage modulus (E') of 2.00 MPa and a loss tangent (tanδ) of 0.11 at 23°C and a frequency of 100 Hz, and a dynamic storage modulus (E') of 2.33 MPa and a loss tangent (tanδ) of 0.12 at 23°C and a frequency of 1000 Hz, a durometer A hardness according to JIS K6253-3 of 30, a plate thickness of 1.6 mm, and a height of 10 mm in the direction perpendicular to the membrane portion 2. However, only the outermost support wall portion 3 has a plate thickness of half that, 0.8 mm. The areal density of this configuration is 2.52 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0068] [Example 5] The soundproof structure 1 (not shown) of Example 5 has the same structure as 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 weight portion 4 of this example are the same as the support wall portion 3 and weight portion 4 of Example 1. The film portion 2 of this example is made of EPDM having a durometer A hardness of 30 according to IS K6253-3, the same material as the support wall portion 3 of Example 4, and its shape and dimensions are the same as the film portion 2 of Example 1. The surface density of this configuration is 2.83 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0069] [Example 6] The soundproof structure 1 of Example 6 shown in Figure 23 has the same structure as Example 1, but has compartments 5 that are wider than the compartments 5 of Example 1. Figure 23(A) is a perspective view of the soundproof structure 1, and Figure 23(B) is a cross-sectional view taken along line AA and turned upside down. The film portion 2 and weight portion 4 of this example are the same as the film portion 2 and weight portion 4 of Example 1. The support wall portions 3 of this example are the same as the support wall portions 3 of Example 1, but are arranged side by side at wider intervals than in Example 1. As a result, each compartment 5 of this example is a square of 50 mm x 50 mm, and its area is 2500 mm. 2 The areal density of this configuration is 1.60 kg / m 2 There are nine sections 5 in a 200 mm × 200 mm square area (evaluation surface) of the film part 2. However, only a part of this area is shown in the drawing. The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in Figure 19(B).

[0070] [Example 7] The soundproof structure 1 (not shown) of Example 7 has the same structure as Example 1, but the weight 4 is cylindrical with a diameter of 13 mm and a height (dimension in the direction perpendicular to the film 2) of 9 mm. Of this weight 4, the spring portion 4a, which is the portion attached to the film 2, has a height of 4 mm and is made of an elastic body having a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at 23°C and at frequencies of 1 Hz to 1000 Hz, and a loss tangent of 0.01 or more and 0.50 or less at 23°C and at frequencies of 1 Hz to 1000 Hz. More specifically, the spring portion 4a in this embodiment is made of polyurethane foam having a dynamic storage modulus of 0.06 MPa and a loss tangent (tanδ) of 0.15 at 23°C and 1 Hz, a dynamic storage modulus (E') of 0.07 MPa and a loss tangent (tanδ) of 0.15 at 23°C and 10 Hz, a dynamic storage modulus (E') of 0.08 MPa and a loss tangent (tanδ) of 0.15 at 23°C and 100 Hz, and a dynamic storage modulus (E') of 0.10 MPa and a loss tangent (tanδ) of 0.15 at 23°C and 1000 Hz. The mass portion 4b, which is the portion of the weight portion 4 opposite the side attached to the membrane portion 2, is 5 mm high and made of EPDM having a durometer A hardness of 65 according to JIS K6253-3. The mass of the weight portion 4 is approximately 1.0 g.

[0071] The membrane part 2 and the support wall part 3 of this embodiment are the same as the membrane part 2 and the support wall part 3 of Example 1. The surface density of this structure is 3.08 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0072] [Example 8] The soundproof structure 1 (not shown) of Example 8 has the same structure as the soundproof structure 1 shown in FIG. 14. The film 2 and support wall 3 of this example are the same as those of Example 1, but the weight 4 of this example consists of a small-diameter, cylindrical spring 4a and a large-diameter, cylindrical mass 4b. The spring 4a, which is the part of the weight 4 attached to the film 2, is cylindrical with a diameter of 6 mm and a height (dimension perpendicular to the film 2) of 3 mm and is made of the same material as the spring 4a of the weight 4 of Example 1 (silicone rubber with a durometer A hardness of 10 according to JIS K6253-3). The mass 4b, which is the part of the weight 4 opposite the part attached to the film 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 weight 4 has a mass of approximately 1.0 g. The areal density of this configuration is 3.13 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in Figures 19(C) and 20(A).

[0073] [Example 9] The soundproof structure 1 (not shown) of Example 9 has the same structure as the soundproof structure 1 shown in Fig. 14. The film portion 2 and weight portion 4 of this example are the same as the film portion 2 and weight portion 4 of Example 8, but the support wall portion 3 of this example is made of EPDM having a durometer A hardness of 30 according to JIS K6253, a plate thickness of 1.6 mm, and a height of 10 mm in the direction perpendicular to the film portion 2. The surface density of this structure is 2.81 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in Figures 20(A) to 20(C).

[0074] [Example 10] The soundproof structure 1 of Example 10 shown in Fig. 24 has the same structure as the soundproof structure 1 shown in Fig. 14. Fig. 24 is a cross-sectional view of the soundproof structure 1. The film portion 2 and weight portion 4 of this example are the same as the film portion 2 and weight portion 4 of Example 9, but the support wall portion 3 of this example is made of EPDM having a durometer A hardness of 30 according to JIS K6253, a plate thickness of 1.6 mm, and a height of 14 mm in the direction perpendicular to the film portion 2. The surface density of this structure is 3.16 kg / m 2The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0075] [Example 11] The soundproof structure 1 of Example 11 shown in Figure 25 has the same structure as the soundproof structure 1 shown in Figure 14. Figure 25(A) is a perspective view of the soundproof structure 1, and Figure 25(B) is a cross-sectional view of the soundproof structure 1 cut along line BB and inverted upside down. The film portion 2 and weight portion 4 of this example are the same as the film portion 2 and weight portion 4 of Example 9, but in this example, some support wall portions 3d of the multiple support wall portions are taller in the direction perpendicular to the film portion 2 than other support wall portions 3c. In other words, the soundproof structure 1 of this example has support wall portions (some support wall portions) 3d that are tall like the support wall portions 3 of Example 10, and support wall portions (other support wall portions) 3c that are short like the support wall portions 3 of Example 9. Specifically, the support wall portion 3c is made of EPDM having a durometer A hardness of 30 according to JIS K6253, a plate thickness of 1.6 mm, and a height of 10 mm in a direction perpendicular to the membrane portion 2, while the support wall portion 3d is made of EPDM having a durometer A hardness of 30 according to JIS K6253, a plate thickness of 1.6 mm, and a height of 15 mm in a direction perpendicular to the membrane portion 2. The support wall portion 3d has a height 1.5 times that of the support wall portion 3c. In this embodiment, as shown in Figures 25(A) and 25(B), rows in which high-height support wall portions 3d are arranged alternate with rows in which only low-height support wall portions 3c are arranged. As a result, of the 49 square compartments 5 arranged in a 7x7 grid, 16 compartments 5 are surrounded by high-height support wall portions 3d. The surface density of this configuration is 3.02 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0076] [Example 12] The soundproof structure 1 (not shown) of Example 12 has the same structure as the soundproof structure 1 shown in Fig. 14. The weight portion 4 of this example is the same as the weight portion 4 of Example 8. The membrane portion 2 and supporting wall portion 3 of this embodiment are formed by integral molding of a styrene-based thermoplastic elastomer (TPS) with a dynamic storage modulus (E') of 7.81 MPa and a loss tangent (tanδ) of 0.06 at 23°C and a frequency of 1 Hz, a dynamic storage modulus (E') of 8.62 MPa and a loss tangent (tanδ) of 0.08 at 23°C and a frequency of 10 Hz, a dynamic storage modulus (E') of 9.19 MPa and a loss tangent (tanδ) of 0.11 at 23°C and a frequency of 100 Hz, and a dynamic storage modulus (E') of 10.3 MPa and a loss tangent (tanδ) of 0.08 at 23°C and a frequency of 1000 Hz, a durometer A hardness of 50 according to JIS K6253, a membrane portion 2 thickness of 1.0 mm, a supporting wall portion 3 thickness of 1.2 mm, and a height perpendicular to the membrane portion 2 of 10 mm. The areal density of this configuration is 2.56 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0077] [Example 13] The soundproof structure 1 (not shown) of Example 13 has the same structure as the soundproof structure 1 shown in Fig. 14. 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 part of the weight portion 4 that is attached to the membrane portion 2, is cylindrical with a diameter of 6 mm and a height (dimension perpendicular to the membrane portion 2) of 3 mm, and is made of TPS with a dynamic storage modulus (E') of 0.19 MPa and a loss tangent (tanδ) of 0.03 at 23°C and a frequency of 1 Hz, a dynamic storage modulus (E') of 0.19 MPa and a loss tangent (tanδ) of 0.04 at 23°C and a frequency of 10 Hz, a dynamic storage modulus (E') of 0.19 MPa and a loss tangent (tanδ) of 0.25 at 23°C and a frequency of 100 Hz, and a dynamic storage modulus (E') of 0.23 MPa and a loss tangent (tanδ) of 0.04 at 23°C and a frequency of 1000 Hz, and a durometer A hardness of 5 according to JIS K6253. The mass portion 4b, which is the portion of the weight portion 4 opposite to the side attached to the membrane portion 2, is cylindrical with a diameter of 11 mm and a height of 6 mm, and is made of EPDM having a durometer A hardness of 70 according to JIS K6253-3. The surface density of this structure is 2.50 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0078] [Example 14] The soundproof structure 1 (not shown) of Example 14 has the same structure as the soundproof structure 1 shown in FIG. 14. The film portion 2 and support wall portion 3 of this example are the same as the film portion 2 and 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 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 mass portion 4b of the weight portion 4 in this embodiment are made of TPS having a dynamic storage modulus (E') of 0.21 MPa and a loss tangent (tanδ) of 0.04 at 23°C and a frequency of 1 Hz, a dynamic storage modulus (E') of 0.23 MPa and a loss tangent (tanδ) of 0.03 at 23°C and a frequency of 10 Hz, a dynamic storage modulus (E') of 0.29 MPa and a loss tangent (tanδ) of 0.05 at 23°C and a frequency of 100 Hz, and a dynamic storage modulus (E') of 0.25 MPa and a loss tangent (tanδ) of 0.17 at 23°C and a frequency of 1000 Hz, and a durometer A hardness of 5 according to JIS K6253. The areal density of this configuration is 2.14 kg / m 2 The sound insulation of the soundproof structure 1 of this example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0079] [Comparative Example 1] As Comparative Example 1, the theoretical sound insulation value calculated based on the mass law when a member having the same mass as that of the soundproof structure 1 of Example 1 is placed is obtained, and the relationship between the 1 / 3 octave band center frequency and the sound transmission loss is shown in Figure 18(A). The surface density of this structure is 2.90 kg / m 2 is.

[0080] Comparative Example 2 As Comparative Example 2, the sound insulation of only the film portion 2 was measured in the same manner as in Example 1, and the relationship between the 1 / 3 octave band center frequency and the sound transmission loss is shown in Figure 18(A). The film portion 2 of this Comparative Example is the same as the film portion 2 of Example 1, and does not have the support wall portion 3 and weight portion 4 as in Example 1. The surface density of this configuration is 0.68 kg / m2 is.

[0081] Comparative Example 3 As Comparative Example 3, a soundproof structure consisting only of a film portion 2 and a supporting wall portion 3 was fabricated as shown in Figure 26. Figure 26(A) is a perspective view of this soundproof structure, and Figure 26(B) is a cross-sectional view taken along line AA and turned upside down. The sound insulation of the soundproof structure was measured using the same method as in Example 1, and the relationship between the 1 / 3 octave band center frequency and the sound transmission loss is shown in Figures 18(A) to 18(B) and 19(C). The film portion 2 and supporting wall portion 3 of this comparative example are the same as those of Example 1, but there is no weight portion 4. The surface density of this structure is 2.43 kg / m 2 is.

[0082] Comparative Example 4 The soundproof 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 weight portion 4 of this comparative example are the same as the film portion 2 and weight portion 4 of Example 1. The support wall 3 of this comparative example is made of polylactic acid (PLA resin) having a dynamic storage modulus (E') of 2.03 GPa and a loss tangent (tan δ) of 0.0045 at 23°C and a frequency of 1 Hz, a dynamic storage modulus (E') of 2.04 GPa and a loss tangent (tan δ) of 0.000060 at 23°C and a frequency of 10 Hz, a dynamic storage modulus (E') of 2.05 GPa and a loss tangent (tan δ) of 0.045 at 23°C and a frequency of 100 Hz, and a dynamic storage modulus (E') of 2.07 GPa and a loss tangent (tan δ) of 0.0079 at 23°C and a frequency of 1000 Hz, and its shape and dimensions are the same as those of the support wall 3 of Example 1. The areal density of this configuration is 2.63 kg / m 2 The sound insulation of the soundproof structure of this comparative example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0083] Comparative Example 5 As Comparative Example 5, a soundproof structure consisting only of a film portion 2 and a supporting wall portion 3 was fabricated in the same manner as in Comparative Example 3, and its sound insulation was measured in the same manner as in Example 1. Figure 21(A) shows the relationship between the 1 / 3 octave band center frequency and the sound transmission loss. The film portion 2 and supporting wall portion 3 of this comparative example are different from the film portion 2 and supporting wall portion 3 of Example 1 and Comparative Example 3, but are the same as the film portion 2 and supporting wall portion 3 of Example 12. Furthermore, the soundproof structure of this comparative example does not have a weight portion 4. The surface density of this configuration is 1.88 kg / m 2 is.

[0084] Comparative Example 6 The soundproof structure of Comparative Example 6 (not shown) has the same structure as Example 1, but has a film portion 2 made of a resin material with a thinner film thickness than the film portion 2 of Example 1. The supporting wall portion 3 and weight portion 4 of this comparative example are the same as the supporting wall portion 3 and weight portion 4 of Example 1. The film portion 2 of this comparative example is made of low-density polyethylene (LDPE) with a film thickness of 0.05 mm. The surface density of this structure is 2.25 kg / m 2 The sound insulation of the soundproof structure of this comparative example was determined in the same manner as in Example 1, and the results are shown in FIG.

[0085] [result] The results of comparing the above-mentioned Examples 1 to 14 of the present invention with Comparative Examples 1 to 6 will be explained. Referring to Fig. 18(A), it can be seen that the soundproofing structure 1 of the present invention improves the soundproofing effect. In particular, the soundproofing structure 1 of Example 1 provides a soundproofing effect significantly greater than the theoretical value based on the mass law (Comparative Example 1) in the frequency band higher than 630 Hz, demonstrating the great effect of the present invention. Furthermore, when compared with Comparative Examples 2 and 3, it can be seen that Example 1, which has a film portion 2, a support wall portion 3, and a weight portion 4, has greater soundproofing properties, particularly in the frequency band lower than 1.25 kHz.

[0086] 18(B), it can be seen that the soundproof structure 1 of Example 1 and the soundproof structures 1 of Examples 2 and 3, which are modifications thereof, can similarly achieve good sound insulation. When the weight 4 itself constitutes a spring-mass resonator, as in Example 1, particularly good sound insulation is achieved near frequencies (e.g., 630 Hz to 1000 Hz) where the vibration of the membrane 2 is reduced by the resonance of the spring-mass resonator. On the other hand, when the spring-mass resonator is formed by the weight 7 and the membrane 2, as in Examples 2 and 3, the frequency band where sound insulation is particularly good can be adjusted by adjusting the weight of the weight 7. For example, if the weight 7 has a mass similar to that of the weight 4 of Example 1, the frequency band where sound insulation is particularly good is around 1000 Hz. By reducing the weight of the weight 7, the frequency band where sound insulation is particularly good can be shifted to a higher frequency.

[0087] 18(C), it can be seen that if the support wall 3 of the soundproof structure is not made of a flexible material, the sound insulation performance is low, but if the support wall 3 is made of a flexible material, a good sound insulation effect can be obtained. This is thought to be because if the support wall 3 is made of a hard material rather than a flexible material, vibrations are easily transmitted to the membrane 2 via the support wall 3, whereas if the support wall 3 is made of a flexible material, vibrations are less likely to be transmitted to the membrane 2 via the support wall 3. Note that the frequency band in which sound insulation is particularly good can be adjusted by changing the hardness of the support wall 3. For example, if the support wall 3 is made softer, the frequency band in which sound insulation is particularly good can be shifted to a lower frequency side.

[0088] 19(A), it can be seen that if the film part 2 of the soundproof structure is too soft, the sound insulation performance will be slightly reduced. This is thought to be because if the film part 2 is too soft, vibrations of a level that allows the spring mass resonator to function adequately will not be transmitted to the spring mass resonator.

[0089] Referring to Figure 19(B), it can be seen that if each section 5 of the membrane section 2 defined by the support wall section 3 of the soundproof structure is too large, the sound insulation performance will be slightly reduced. This is thought to be because if each section 5 is too large, the spring mass resonator will not function sufficiently, and the vibration reduction effect will be reduced. Therefore, each section 5 should be made small to some extent (for example, 1000 mm 2 ) is preferred.

[0090] 19(C) shows that even if the material and shape of the weight 4 of the soundproof structure are different, as long as the material and shape are within the preferred ranges, the soundproofing function of the present invention will be exhibited. Therefore, it is clear that the material and shape of the weight 4, etc. can be freely set within the preferred ranges.

[0091] 20(A) shows that a similar sound-insulating effect can be obtained even if the durometer A hardness according to JIS K6253-3 of the support wall portion 3 differs to some extent. And, referring to Fig. 20(B) shows that a similar sound-insulating effect can be obtained even if the height of the support wall portion 3 extending in the direction perpendicular to the film portion 2 differs to some extent.

[0092] 21(C), it can be seen that a good soundproofing effect can be obtained even if only some of the support walls 3d among the plurality of support walls are made taller in the direction perpendicular to the film portion 2, while the heights of the other support walls 3c are made shorter. When the sound source or the soundproof structure 1 is mounted on an external member (not shown) and supported, if there are too few tall support walls 3d, it becomes difficult to stably support the soundproof structure 1, and if there are too many, the weight of the entire soundproof structure 1 increases. Therefore, it is preferable that the compartments 5 surrounded by the tall support walls 3d account for 5% or more of the total compartments 5 of the soundproof structure 1. Furthermore, when a cross section of each support wall 3c, 3d parallel to the film portion 2 is viewed, it is preferable that the total cross-sectional area of ​​the tall support walls 3d is 10% or more of the total cross-sectional area of ​​all the support walls 3c, 3d of the soundproof structure 1. In Example 11, a 20mm x 20mm (area 400cm) section of the film portion 2, which has a planar shape of 25mm x 25mm, is enclosed by the 20mm x 20mm (area 400cm) section. 2) there are 7 x 7 = 49 compartments 5, of which 16 compartments 5 are compartments 5 surrounded by high support wall portions 3d, which is a preferable proportion of 32.6%.

[0093] In addition, even if the height of all support wall portions 3 is high as in Example 10, or even if the height of only some support wall portions 3d is high as in Example 11, it is preferable to keep the height of the entire soundproof structure 1 to 20 mm or less, as mentioned above, in order to prevent an increase in the weight of the entire soundproof structure 1 and installation restrictions.

[0094] Referring to FIG. 21(A), it can be seen that even if the membrane portion 2 and the support wall portion 3 are formed by integral molding of a thermoplastic material, the provision of the weight portion 4 provides good sound insulation. In a spring-mass resonator consisting of the spring portion 4a and the mass portion 4b of the weight portion 4, as in Example 13, it can be seen that if the spring portion 4a is softer, the resonant frequency shifts to the lower frequency side, and a greater sound insulation effect can be obtained at the lower frequency side. In this way, by changing the configuration of the weight portion 4, it is possible to adjust the sound insulation frequency band. Furthermore, it can be seen that good sound insulation can be obtained even if the weight portion 4 is made of a single material, as in Example 14. Therefore, productivity can be improved by manufacturing the weight portion 4 from a single material.

[0095] In addition to the soundproof structure 1 having the structure exemplified in Examples 1 to 14 described above, the present invention may employ the structures shown in Examples 1 to 14 as the soundproof structure 1a of the soundproof structure 1, which includes a soundproof structure 1a and a soundproof plate-like portion 1b, as shown in Figures 5 to 6. In this case, the difference in sound insulation properties of the structures (soundproof structure 1a) exemplified in Examples 1 to 14 described above can be said to represent the difference in sound insulation properties of the soundproof structure 1. Furthermore, as described above, the structures (soundproof structure 1a) of Examples 1 to 14 have greater sound insulation properties than the structures of Comparative Examples 1 to 6. Furthermore, the inclusion of the soundproof plate-like portion 1b in the soundproof structure 1 is thought to provide even better sound insulation. In particular, in electric vehicles, a heavy motor located in the floor of the vehicle cabin (not shown) may have the effect of suppressing vibrations in the floor area, but its effect of suppressing noise from areas other than the floor area is limited. Therefore, suppressing noise from all directions into the vehicle cabin 13 of an automobile 10 using the present invention is extremely effective in quieting the vehicle cabin 13 of an electric vehicle.

[0096] The present invention may have the following configuration. [1] It is arranged in at least a part of a member that partially separates the interior of a vehicle from the outside of the vehicle, The device has an elastic membrane portion, an elastic support wall portion erected on the membrane portion, and a weight portion erected on the membrane portion, the membrane portion is divided into a plurality of compartments by the support wall portion, and the weight portion is located inside each 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 disposed in one compartment, a height of the support wall portion extending in a direction perpendicular to the membrane portion is greater than a height of the weight portion extending in a direction perpendicular to the membrane portion; A soundproof structure, characterized in that each of the weight portions constitutes a spring-mass resonator having an elastic spring portion and a mass portion having a mass greater than that of the spring portion. [2] The soundproof structure described in [1], wherein the membrane portion, the support wall portion, and the spring portion are all made of either a material that does not have energy elasticity but has rubber elasticity, a material that does not have rubber elasticity but has energy elasticity, or a material that has both rubber elasticity and energy elasticity. [3] The soundproof structure according to [1] or [2], wherein the membrane portion, the support wall portion, and the spring portion all have a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at 23°C and a frequency of 1 Hz to 1000 Hz. [4] A soundproof structure according to any one of [1] to [3], wherein the film portion, the support wall portion, and the spring portion all have a loss tangent of 0.01 or more and 0.50 or less at 23°C and a frequency of 1 Hz to 1000 Hz. [5] A soundproof structure described in any one of [1] to [4], wherein the spring portion is located on the side of the weight portion attached to the membrane portion, and the mass portion is located on the side opposite to the side of the weight portion attached to the membrane portion. [6] It is arranged in at least a part of a member that partially separates the interior of a vehicle from the outside of the vehicle, The device has an elastic membrane portion, an elastic support wall portion erected on the membrane portion, and a weight portion erected on the membrane portion, the membrane portion is divided into a plurality of compartments by the support wall portion, and the weight portion is located inside each 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 disposed in one compartment, a height of the support wall portion extending in a direction perpendicular to the membrane portion is greater than a height of the weight portion extending in a direction perpendicular to the membrane portion; A soundproof structure, characterized in that the film portion serves as a spring portion and the weight portion serves as a mass portion to form a spring-mass resonator. [7] The soundproof structure described in [6], wherein both the membrane portion and the supporting wall portion are made of either a material that has rubber elasticity but not energy elasticity, a material that has energy elasticity but not rubber elasticity, or a material that has both rubber elasticity and energy elasticity. [8] The soundproof structure according to [6] or [7], wherein the film portion and the supporting wall portion each have a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at 23°C and a frequency of 1 Hz to 1000 Hz. [9] The soundproof structure according to any one of [6] to [8], wherein the film portion and the supporting wall portion each have a loss tangent of 0.01 or more and 0.50 or less at 23°C and a frequency of 1 Hz to 1000 Hz.

[10] A soundproof structure according to any one of [1] to [9], wherein the soundproof structure is arranged in at least one of the roof of the automobile, the pillar supporting the roof, the door trim, the fender liner partially covering the tire, the trunk side, and the trunk trim.

[11] A soundproof structure according to any one of [1] to

[10] , which is arranged inside an electric vehicle. [Explanation of symbols]

[0097] 1. Soundproofing structure 1a Sound insulation structure 1b Soundproof plate part 2 Membrane part 3 Support wall section 3a 1st wall 3b 2nd wall part 3c Low-height supporting wall 3d High supporting wall 4 Weight part 4a Spring part 4b Mass part 5 plots 7 Weight 10. Automobiles 10a Roof section 10b, 10c Pillar section 10d Door section 10e, 10f fender section 10g trunk section 11,12 Tires 13 Cabin 14 Door trim 15 Fender liner 16 Trunk trim 17 Trunk side

Claims

1. The vehicle is provided with a member that partially separates the interior of the vehicle from the exterior of the vehicle. The device has an elastic membrane portion, an elastic support wall portion erected on the membrane portion, and a weight portion erected on the membrane portion, the membrane portion is divided into a plurality of compartments by the support wall portion, and the weight portion is located inside each 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 disposed in one compartment, a height of the support wall portion extending in a direction perpendicular to the membrane portion is greater than a height of the weight portion extending in a direction perpendicular to the membrane portion; A soundproof structure, characterized in that each of the weight portions constitutes a spring-mass resonator having an elastic spring portion and a mass portion having a mass greater than that of the spring portion.

2. 2. The soundproof structure of claim 1, wherein the membrane portion, the support wall portion, and the spring portion are all made of a material that has rubber elasticity but not energy elasticity, a material that has energy elasticity but not rubber elasticity, or a material that has both rubber elasticity and energy elasticity.

3. 3. The soundproof structure according to claim 1, wherein the membrane portion, the support wall portion, and the spring portion all have a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at 23°C and a frequency of 1 Hz to 1000 Hz.

4. 4. The soundproof structure according to claim 3, wherein the film portion, the support wall portion, and the spring portion all have a loss tangent of 0.01 or more and 0.50 or less at 23° C. and a frequency of 1 Hz to 1000 Hz.

5. 3. The soundproof structure according to claim 1, wherein the spring portion is located on the side of the weight portion attached to the membrane portion, and the mass portion is located on the opposite side of the weight portion from the side attached to the membrane portion.

6. The vehicle is provided with a member that partially separates the interior of the vehicle from the exterior of the vehicle. The device has an elastic membrane portion, an elastic support wall portion erected on the membrane portion, and a weight portion erected on the membrane portion, the membrane portion is divided into a plurality of compartments by the support wall portion, and the weight portion is located inside each 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 disposed in one compartment, a height of the support wall portion extending in a direction perpendicular to the membrane portion is greater than a height of the weight portion extending in a direction perpendicular to the membrane portion; A soundproof structure, characterized in that the film portion serves as a spring portion and the weight portion serves as a mass portion to form a spring-mass resonator.

7. 7. The soundproof structure according to claim 6, wherein the membrane portion and the support wall portion are made of a material that has rubber elasticity but not energy elasticity, a material that has energy elasticity but not rubber elasticity, or a material that has both rubber elasticity and energy elasticity.

8. 8. The soundproof structure according to claim 6, wherein the film portion and the supporting wall portion each have a dynamic storage modulus of 0.01 MPa or more and 100 MPa or less at 23° C. and a frequency of 1 Hz to 1000 Hz.

9. 9. The soundproof structure according to claim 8, wherein the film portion and the support wall portion each have a loss tangent of 0.01 or more and 0.50 or less at 23° C. and a frequency range of 1 Hz to 1000 Hz.

10. 10. The soundproof structure according to claim 1, wherein the soundproof structure is disposed in at least one of a roof of an automobile, a pillar supporting the roof, a door trim, a fender liner partially covering a tire, a trunk side, and a trunk trim.

11. The soundproof structure according to claim 1 or 6, which is disposed inside an electric vehicle.

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