JP4997057B2 - Sound insulation for vehicles - Google Patents

Description

  The present invention relates to a vehicle soundproofing material that is attached to the interior side of a vehicle body panel, and more particularly to a vehicle soundproofing material that can exhibit excellent soundproofing performance by enhancing a membrane vibration sound absorbing function while achieving weight reduction.

  Usually, in order to enhance the quietness of the vehicle interior, various soundproof materials are attached to the interior side of the vehicle body panel as the soundproof structure of the vehicle. As an example of this soundproof material, there is an insulator dash attached to the interior side of a dash panel that partitions an engine room and a vehicle interior. A conventional example of this insulator dash will be described with reference to FIG. In the drawing, an insulator dash 2 is attached to the interior surface side of the dash panel 1 that divides the engine room E and the vehicle compartment R, and the insulator dash 2 is enlarged as shown in FIG. A sound absorbing layer 3 for absorbing noise transmitted through the dash panel 1 into the vehicle interior R by a porous sound absorbing function and a skin layer 4 laminated on the surface of the sound absorbing layer 3 are configured.

  And as a material of the sound absorbing layer 3 in the insulator dash 2, a material capable of obtaining a porous sound absorbing function such as felt, non-woven mat, or foam can be used. As the skin layer 4, the sound insulating type shown in FIG. When applied to the insulator dash 2, a sound insulating material 4A made of a high-density material such as a recycled rubber sheet or a recycled PVC sheet is used. Moreover, when applying to the ventilation type | mold insulator dash 2A of FIG.19 (b), the lightweight high-density ventilation layer 4B which has air permeability, such as a nonwoven fabric mat, is used. The configuration of the conventional example of the sound insulation type insulator dash 2 is described in Patent Document 1, and the configuration of the conventional example of the ventilation type insulator dash 2A is described in Patent Document 2.

Japanese Utility Model Publication No. 7-5966

Special Table 2002-505209

  Thus, conventionally, for example, as shown in FIG. 19A, the sound insulation type insulator dash 2 uses a heavy material such as a recycled rubber sheet and a recycled PVC sheet as the sound insulating material 4A. However, this increases the weight of the product and reduces the fuel efficiency and the mounting workability. Further, in terms of sound absorption performance, it has been pointed out that the sound absorption effect of high frequency range noise is not sufficient, and satisfactory soundproof performance cannot be obtained.

  On the other hand, the breathable insulator dash 2A shown in FIG. 19B uses a high-density breathable layer 4B such as a nonwoven fabric in place of the heavy sound insulating material 4A. As the fibers used are mainly recycled products, the specifications of the fibers differ depending on the season, and the resistance to airflow tends to fluctuate due to variations in thickness, etc., making it difficult to achieve uniform sound absorption performance. . In addition, the filaments are likely to fall off due to long-term use, leading to a decrease in sound absorption performance, and not preferable from the environmental aspect of the passenger compartment. Furthermore, as a method of reducing the noise level in the low frequency range, it has been dealt with by increasing the weight per unit area of the sound absorbing layer 3, but in this case, the material cost and the molding processing cost will rise, leading to an increase in cost. At the same time, there is a problem that the molding cycle is prolonged and productivity is greatly reduced.

  The present invention has been made in view of such circumstances, and is a vehicle soundproofing material that is mounted on the interior side of a vehicle body panel. In particular, while achieving weight reduction, a membrane vibration sound absorbing function by a resonance layer is provided. An object of the present invention is to provide a vehicle soundproofing material capable of obtaining an excellent soundproofing performance by increasing the noise.

  In order to solve the above-described problems, the present invention provides a vehicle soundproofing material that is mounted on the interior side of a vehicle body panel, and the vehicle soundproofing material transmits porous sound absorption through the vehicle body panel to the indoor side. In the vehicle soundproofing material comprising at least one sound absorbing layer that absorbs sound by function and at least a resonance layer that is integrated with the sound absorbing layer in order to absorb noise propagating from the sound absorbing layer by resonance action, the resonance layer Is a bond in which the bending load is set to be small within a range of 0.01 to 5 mm, and the area between the sound absorbing layer and the resonance layer has an occupation area of 0 to 50% with respect to the entire joint surface of both. It is characterized by being integrated by layers.

  Here, the installation location of the soundproofing material can be applied to the vehicle interior side surface of the vehicle body panel, the luggage room inner surface, the trunk room inner surface, and the like. In addition, examples of the product form include an insulator dash, a roof trim, a soundproof portion on a floor carpet, a luggage trim, a trunk trim, and the like.

The present invention is a soundproofing material including at least a two-layer laminate of a sound absorbing layer and a resonance layer. The sound absorbing layer is not particularly limited as long as it is a material that can absorb noise propagating from the vehicle body panel to the vehicle interior side by the porous sound absorbing function. For example, it is selected from felt, synthetic fiber non-woven fabric such as PET (polyester) fiber, fiber aggregate made of paper (pulp or the like), urethane foam sheet and the like. Usually, a raw fabric mat in which fiber aggregates are collected in a mat shape is heat-softened and then press-molded by a cold press mold having a required shape. The physical properties of the sound absorbing layer are set in the range of thickness 1 to 70 mm, density 0.01 to 1.0 g / cm ³ , and surface density 200 to 2400 g / m ² . The sound absorbing layer may be a single layer, but a multi-layered sound absorbing layer structure having different physical properties may be employed.

  Next, a non-breathable material is suitable for the resonance layer in order to maintain good sound insulation performance, but a breathable material can also be used. First, as the material of the non-breathable material, a polyolefin resin foam sheet such as polypropylene foam or polyethylene foam, a resin foam such as polyurethane foam sheet, or a resin film can be used. In the case of a foam, a thickness of 0.1 to 5 mm, preferably 2 mm or less is suitable, and the thickness of the resin film is in the range of 10 to 500 μm.

On the other hand, the same material as the non-breathable material is used as the breathable material, but for the foam, an open-cell type is used, and for the resin film, the needle hole is processed to provide breathability. is doing. The air permeability of the breathable material is set in the range of 0.5 to 25 cm ³ / cm ² · sec (measured by a fragile type tester), but the thickness, density, surface density, maximum bending load The numerical value may be set the same as the material of the non-breathable material.

In both cases, the density is 0.02 to 1.20 g / cm ³ and the surface density is 500 g / m ² or less. In particular, the resonance layer is made thin and bending load in order to easily cause vibration of the resonance layer itself. The feature is to reduce the size. As the bending load, the maximum bending load is 0.001 to 5N, preferably 0.001 to 1N.

  Next, with respect to the adhesion between the sound absorbing layer and the resonance layer, the adhesive layer is interposed in an occupied area of 0 to 50% with respect to the entire bonding surface between the sound absorbing layer and the resonance layer. The material of the adhesive may be appropriately selected from resin powder such as polyethylene powder, adhesive film, reticulated hot melt, liquid spray paste, etc. in consideration of the material of the sound absorbing layer and the resonance layer. In this case, the area occupied by the adhesive layer is specified as 0 to 50%, but in the case of 0%, an adhesive is used by utilizing the adhesive property of the binder fiber or binder resin impregnated in the sound absorbing layer. It means a configuration in which the sound absorbing layer and the resonance layer are bonded and integrated. In other words, for the integration of the sound absorption layer and the resonance layer, the binder fiber in the sound absorption layer without using an adhesive, the binder fiber in the sound absorption layer is integrated using only the binder resin, By using a binder resin to disperse and adhere adhesive powder or spray paste in a sparse form, or by using a perforated film or a reticulated hot melt, the use of an adhesive can be minimized. Therefore, the sound absorbing layer and the resonance layer can be integrated through the adhesive layer having an occupation area of 50% or less with respect to the entire joint surface of both.

  As is apparent from the above configuration, the vehicle soundproofing material according to the present invention includes at least two layers of at least one sound absorbing layer as a base and a resonance layer integrated on the surface side thereof. By making it thin and setting the bending load small, vibration is likely to occur, and the membrane vibration sound absorbing function can be enhanced. Furthermore, for the integration of the sound absorption layer and the resonance layer, by using the binder fiber or binder resin in the sound absorption layer effectively, no adhesive is used, or the adhesive powder is dispersed and adhered in a sparse manner, etc. , Through an adhesive layer having an occupation area of 50% or less, which is advantageous in terms of cost.

  Next, in a preferred embodiment of the present invention, at least one second sound absorbing layer on the surface side of the laminate composed of the sound absorbing layer and the resonance layer is zero with respect to the entire joint surface between the resonance layer and the sound absorption layer. It is integrated through an adhesive layer having an occupation area of ˜50%, and a resonance layer having a resonance action is interposed between the sound absorption layer of the base and the second sound absorption layer. To do.

Here, the material of the second sound absorbing layer integrated on the surface side of the resonance layer is the same material as the sound absorbing layer (hereinafter referred to as the base sound absorbing layer) located between the vehicle body panel and the resonance layer. Can be used. For example, it is possible to use synthetic fiber nonwoven fabrics such as felt and PET (polyester) fibers, fiber aggregates made of paper (pulp and the like) in the form of fibers, and foamed resin sheets such as polyurethane foams can be used. . The physical properties are set to a range of 1 to 70 mm in thickness, 0.01 to 1.0 g / cm ³ in density, and 200 to 2400 g / m ^{2 in} surface density. The second sound absorbing layer may be a single layer, but a multi-layered sound absorbing layer structure having different physical properties may be employed.

  Furthermore, for the integration of the resonance layer and the second sound absorbing layer, as described above, the occupation area of the adhesive layer is preferably set in the range of 0 to 50%. Specifically, as the material of the adhesive, resin powder, adhesive film, reticulated hot melt, liquid spray paste, etc. can be used, and the adhesive properties of the binder fiber and binder resin in the second sound absorbing layer are effectively utilized. Thus, both can be firmly integrated with no adhesive or with a small amount of adhesive.

  According to this embodiment, since the resonance layer having the membrane vibration absorption function is interposed between the base sound absorption layer having the porous sound absorption function and the second sound absorption layer, the base The noise that propagates from the sound absorbing layer and the resonance layer to the room side can also be absorbed by the second sound absorbing layer, and the noise in the passenger compartment can be taken into the second sound absorbing layer. By further generating vibration, the membrane vibration absorption function can be enhanced, and the sound absorption performance can be further enhanced.

  Next, a further preferred embodiment of the present invention is characterized in that a low air-permeable skin layer is bonded and fixed to the surface side of the at least one second sound absorbing layer.

Here, the low-breathing skin layer bonded to the surface side of the second sound absorbing layer is made of felt, synthetic fiber nonwoven fabric such as PET (polyester) fiber, and fiber assembly made of paper (pulp or the like) in the form of fibers. Body, urethane foam, etc. (open cell type), thickness is 0.1 to 5 mm, density is 0.01 to 1.0 g / cm ³ , and air flow rate is 1 to 25 cm ³ / cm ² · sec ( (Measured value by Frazier type testing machine). The low air permeability skin layer may be set on the entire surface of the second sound absorbing layer, but can also be set limitedly on a part of the surface.

  Furthermore, for the adhesion between the second sound absorbing layer and the low air permeability skin layer, an adhesive and an adhesive structure used for bonding the sound absorbing layer and the resonance layer can be applied. That is, an adhesive such as a resin powder, an adhesive film, a reticulated hot melt, or a liquid spray paste is used. If the binder fiber in the second sound absorbing layer or the binder resin is effectively used, the second sound absorbing layer and The low air permeability skin layer can be bonded and integrated with a small amount of adhesive. The area occupied by the adhesive is set to 0 to 100%.

  According to this embodiment, a triple-wall sound insulation structure including a vehicle body panel, a resonance layer, and a low ventilation skin layer can be expected, and in particular, a sound insulation performance and a sound absorption performance for noise in a middle / high frequency range (630 Hz or more). Can be improved.

  Next, in a further preferred embodiment of the present invention, a cushion layer is interposed on either one of the front and back surfaces of the resonance layer, or at least one side between the sound absorbing layer of the base and the vehicle body panel. It is characterized by being.

Here, as a material of the cushion layer interposed between at least one of the front and back surfaces of the resonance layer or at least one side between the sound absorbing layer of the base and the vehicle body panel, the sound absorbing layer of the base, the second As with the sound absorbing layer, a synthetic nonwoven fabric such as felt and PET (polyester) fibers, a fiber assembly made of paper (pulp or the like) in the form of a fiber, or a foamed molded product such as polyurethane foam can be used. The density is 2 to 5 mm, preferably 0.5 to 2 mm, and the density is 0.01 to 1.0 g / cm ³ , preferably 0.01 to 0.1 g / cm ³ . And about adhesion | attachment with a cushion layer and a sound absorption layer, adhesive agents, such as resin powder, an adhesive film, a net-like hot melt, and a liquid spray paste, can be used. Further, as a method for adhering the cushion layer and the sound absorbing layer, both may be integrated by needle punching without using an adhesive.

  According to this embodiment, for example, when the cushion layer is set on one side or both sides of the resonance layer, the cushioning property of the cushion layer suppresses the vibration of the second sound absorbing layer itself, Has the effect of attenuating radiation and improves sound insulation performance. Further, when the cushion layer is interposed between the base sound absorbing layer and the vehicle body panel, the cushioning property of the cushion layer suppresses the vibration of the base sound absorbing layer and has the effect of attenuating the sound emission due to the vibration.

  Further, as one form of the soundproofing material, a basic sound absorbing layer and a resonance layer are used as a basic structure, and if desired, in addition to a variation in which a second sound absorbing layer is added, the surface of the second sound absorbing layer is reduced. It is also possible to adopt a configuration in which a ventilation skin layer is bonded and a cushion layer is bonded to at least one surface of any sound absorbing layer.

  Furthermore, in a preferred embodiment of the present invention, a sound insulation sheet is set on the room facing surface of the soundproof material.

Here, the sound insulating sheet may be set on the entire surface of the soundproofing material facing the room, but may be locally disposed only on a portion where the sound insulating performance is desired to be improved. As the material of the sound insulation sheet, a non-breathable material such as rubber, EPDM, foamed sheet, or film can be used. However, in the case of a breathable material such as felt or non-woven fabric, the surface density is 50 to 9000 g / m ² and the air flow rate is 0. A material within the range of 5 to 10 cm ³ / cm ² · sec (measured by a Frazier type tester) can be used. It should be noted that it is desirable to use a material that can achieve a significant reduction in weight compared to conventional sound insulation layers, regardless of whether it is non-ventilated or ventilated.

  Therefore, according to this embodiment, it can greatly contribute to the improvement of the sound insulation performance.

  As described above, the vehicle soundproofing material according to the present invention includes at least two layers of the sound absorbing layer that absorbs the noise transmitted through the vehicle body panel by the porous sound absorbing function and the resonance layer integrated on the surface of the sound absorbing layer. Including a vehicle soundproofing material, the resonance layer is thin and the bending load is set small, so that the resonance layer itself is prone to vibration, enhances the membrane vibration absorption function, and improves the sound absorption performance. In addition, the sound absorbing layer and the resonance layer are integrated through an adhesive layer having an occupation area of 0 to 50% with respect to the entire joint surface of both of them, so that the cost of the adhesive can be reduced. Has the effect of lowering.

  Furthermore, according to a preferred embodiment of the vehicle soundproofing material according to the present invention, the sound absorbing performance is improved by using a thin resonance layer with a small bending load, and the second sound absorbing layer and the low air permeability skin layer are provided. By providing or interposing a cushion layer for suppressing vibration in the sound absorbing layer, it is possible to attenuate sound emission and further improve sound insulation.

  Hereinafter, an embodiment of a soundproofing material for a vehicle according to the present invention is applied to an insulator dash mounted on a vehicle interior side of a dash panel, and will be described in detail below. Note that the gist of the present invention is as described in the scope of claims, and the contents of the embodiments described below are merely examples of the present invention.

  1 to 7 show a first embodiment of the present invention. FIG. 1 is a cross-sectional view showing a structure of an insulator dash attached to a dash panel. FIG. 2 is a cross-sectional view showing a material of the insulator dash. Is a graph showing the relationship between the resonance layer and the sound insulation performance in the insulator dash according to the present invention, FIG. 4 is a graph showing the relationship between the resonance layer and the sound absorption performance in the insulator dash according to the present invention, and FIG. 5 is a graph in the insulator dash according to the present invention. 6 is a graph showing the relationship between the occupied area of the adhesive layer and the sound insulation performance, FIG. 6 is a graph showing the relationship between the occupied area of the adhesive layer and the sound absorbing performance in the insulator dash according to the present invention, and FIG. 7 is a modification of the insulator dash according to the present invention. It is sectional drawing which shows an example.

  In FIG. 1, the dash panel 10 that partitions the engine room E and the vehicle compartment R is partitioned into a dash upper portion 10 a, a dash lower portion 10 b, and a toe board portion 10 c from the upper side, and along the indoor surface side of the dash panel 10. An insulator dash 20 is attached. Further, a floor carpet 11 is laid in a wrap shape on the surface side of the insulator dash 20 to be mounted on the toe board portion 10c, and is further mounted on the upper half of the dash upper portion 10a and the dash lower portion 10b of the dash panel 10. The upper half of the insulator dash 20 is located in the instrument panel 12. A crash pad (not shown) is attached to the instrument panel 12.

  By the way, the insulator dash 20 according to the present invention is configured such that the product weight is significantly reduced in order to improve fuel efficiency and mounting workability, and further, sufficient soundproofing characteristics are provided even if the weight is reduced. ing.

  Next, the configuration of the insulator dash 20 will be described with reference to FIG. The insulator dash 20 is disposed on the side facing the dash panel 10 and has a sound absorbing layer 30 of a base capable of effectively absorbing noise in the middle and high frequency regions by a porous sound absorbing function, and a second laminated on the indoor side. Sound absorption layer 40, base sound absorption layer 30, resonance layer 50 having a membrane vibration absorption function interposed between second sound absorption layer 40, and adhesive layer 60 laminated on both surfaces of resonance layer 50. It is roughly structured.

The material structure of the base sound absorbing layer 30 and the second sound absorbing layer 40 will be described. Both the sound absorbing layers 30 and 40 are made of felt, polyester fibers typified by polyethylene terephthalate (PET), synthetic fiber nonwoven fabrics such as polypropylene fibers, fiber aggregates made of paper (pulp or the like), or polypropylene. Use a foam or polyurethane foam formed by mixing a foaming agent selected from inorganic foaming agents such as sodium bicarbonate or organic foaming agents such as azodicarbonamide in a synthetic resin material such as polyethylene and polyester. Can do. The sound absorbing layer 30 and the second sound absorbing layer 40 of the base only need to have a porous sound absorbing function capable of absorbing noise in the middle / high frequency range, and have a thickness of 1 to 70 mm and a density of 0.01 to 1. 0.0 g / cm ³ and the surface density are set to 200 to 2400 g / m ² , respectively. The base sound-absorbing layer 30 and the second sound-absorbing layer 40 each have a single-layer structure, but even if a structure of a plurality of sound-absorbing layers 30 and 40 having different surface densities, fiber properties, etc. is adopted. good.

Next, the resonance layer 50 interposed between the base sound absorbing layer 30 and the second sound absorbing layer 40 is characterized in that it is thin and the bending load is set small in order to improve the sound absorbing performance. That is, the material may be a non-breathable material or a breathable material, and if it is a non-breathable material, a thermoplastic resin foam resin sheet such as polypropylene foam, polyethylene foam, polyurethane foam, or a polypropylene resin film, polyethylene resin film When using a foamed resin sheet, the thickness of the resonance layer 50 should be set to 0.1 to 5 mm, preferably 2 mm or less. When a resin film is used, A thickness of 10 to 500 μm is suitable. The density is 0.02 to 1.20 g / cm ³ , the surface density is set to 500 g / m ² or less, and the maximum bending load is in the range of 0.001 to 5N, preferably 0.001 to 1N. Is good. Note that the resonance layer 50 using a non-breathable material is non-breathable even if it is thin, so that the sound insulation performance can be maintained well, and the sound insulation performance does not deteriorate. As the resonance layer 50, a breathable material can be used as long as the resonance layer 50 is thin, has a small bending load, and can provide an excellent sound absorbing function for membrane vibration. As a material in that case, an open-cell foam or a resin film subjected to needle hole processing is suitable. Further, the air flow rate is preferably set within a range of 0.5 to 25 cm ³ / cm ² · sec (measured value by a Frazier type tester). When a breathable material is used as the resonance layer 50, the sound insulation performance of the middle / high frequency range noise is reduced, but the sound absorption performance tends to be improved. Soundproof effect can be obtained.

  Thus, the insulator dash 20 according to the present invention can exhibit an excellent porous sound absorbing function by the sound absorbing layer 30 and the second sound absorbing layer 40 of the base, maintain a good sound absorbing function, and in particular, both sound absorbing layers. The resonance layer 50 interposed between the layers 30 and 40 is made thin and the bending load is reduced, so that the resonance layer 50 itself is easily oscillated and the membrane vibration absorption function is enhanced. Can effectively absorb noise.

  Further, in the present invention, the sound absorbing performance is maintained well, while the sound absorbing layers 30 and 40 and the resonance layer 50 are the binder fibers and binder resins contained in the base sound absorbing layer 30 and the second sound absorbing layer 40. Thus, the resonance layer 50 and the sound absorbing layers 30 and 40 are integrated with no adhesive or with a small amount of adhesive. That is, the adhesive layer 60 is suppressed to an occupied surface area of 0 to 50% with respect to the entire joint surface between the resonance layer 50, the base sound absorbing layer 30, and the second sound absorbing layer 40. Here, 0% of the adhesive layer 60 means that the resonance layer 50 is bonded and integrated only with the binder fiber or the binder resin inside the base sound absorbing layer 30 and the second sound absorbing layer 40 without using an adhesive. Show. When the adhesive layer 60 is used, resin powder, adhesive film, reticulated hot melt, liquid spray paste or the like can be used for the adhesive, and the occupied area of 50% or less is the above-described resin powder or liquid spray. It means that an adhesive film or a reticulated hot melt that is sparsely adhered or perforated is used by supplying the paste dispersedly to the joint surface. In this embodiment, the area occupied by the adhesive layer 60 is adjusted to 20%. Thus, since the amount of the adhesive used for the adhesive layer 60 can be small, it can contribute to cost reduction.

  Since the insulator dash 20 according to the present invention is configured as described above, from the functional viewpoint, the resonance layer 50 is thin, and the bending load is reduced, so that vibration of the resonance layer 50 itself easily occurs, and membrane vibration The sound absorbing function is improved by enhancing the sound absorbing function. However, as the thickness of the resonance layer 50 becomes thinner, the maximum bending load becomes smaller with respect to the transmission loss and the sound absorption rate, which are standards for the sound insulating performance and the sound absorbing performance. It is clear from the graphs of FIGS. 3 and 4 that the sound insulation performance and the sound absorption performance are improved as the distance increases.

  Further, in the present invention, the area occupied by 0 to 50% is specified as the form of the adhesive layer 60. As described above, the adhesive can be saved and the cost can be reduced. From the graph of 6, the following can be understood. That is, as the resonance layer 50 is restrained by the adhesive layer 60 from the graph shown in FIG. 5, the noise insulation performance of the noise in the low frequency region tends to deteriorate. Next, from the graph shown in FIG. As the adhesive layer 60 is restrained, the sound absorption coefficient over the entire frequency range tends to deteriorate. Accordingly, the graphs of FIGS. 5 and 6 show that the smaller the occupied area of the adhesive layer 60, the better both the sound insulation performance and the sound absorption performance.

  Next, FIG. 7 shows a modified example of the insulator dash 20 according to the present invention. The insulator dash 20 has a simplified structure as compared with the above-described embodiment. The resonance layer 50 is integrated through the adhesive layer 60. Since this insulator dash 20 has a two-layer structure of the base sound absorbing layer 30 and the resonance layer 50, it can contribute to cost reduction and weight reduction by simplifying the structure.

  Next, FIGS. 8 to 11 show a second embodiment of the present invention. In the second embodiment as well, an insulator dash 20A attached to the indoor surface side of the dash panel 10 is applied. The insulator dash 20A according to the second embodiment is characterized by adopting a structure in which a cushion layer 70 is incorporated. As shown in FIG. 8, the insulator dash 20A includes a base sound absorbing layer 30, a resonance layer 50, A cushion layer 70 is interposed therebetween, and an adhesive layer 60 is interposed between the base sound-absorbing layer 30 and the resonance layer 50 on both sides of the cushion layer 70.

Here, the cushion layer 70 as a new structure is made of felt, synthetic fiber nonwoven fabric such as PET (polyester) fiber, fiber aggregate made of paper (pulp or the like) in the form of fiber, or foamed polyurethane or the like. A resin sheet or the like may be either air permeable or air permeable, and the cushion layer 70 has a thickness of 0.2 to 5 mm, preferably 0.5 to 2 mm, and a density of 0.01 to 1.0 g / cm ³ . Preferably, it is set to 0.01 to 0.1 g / cm ^3, and the installation location of the cushion layer 70 may be provided on either one or both of the front and back surfaces of the resonance layer 50. The configurations of the base sound absorbing layer 30, the second sound absorbing layer 40, the resonance layer 50, and the adhesive layer 60 are the same as the configuration of the insulator dash 20 described in the first embodiment, and thus the description thereof is omitted.

  Since the cushion layer 70 is set on one side or both sides of the resonance layer 50 for the insulator dash 20A, the cushioning performance of the cushion layer 70 suppresses the vibration of the second sound absorbing layer 40. It has the effect of attenuating the radiation of sound due to vibration and the effect of improving sound insulation.

  In the second embodiment, the sound absorbing layer 30 and the resonance layer 50, which are members to which the cushion layer 70 is joined, are bonded and integrated through the adhesive layer 60 used in the first embodiment. As a method for adhering the layer 70 and the sound absorbing layer 30 of the base, both may be integrated by needle punching.

  Next, the insulator dash 20A shown in FIG. 9 is obtained by changing the position of the cushion layer 70, and the cushion layer 70 is interposed between the dash panel 10 and the sound absorbing layer 30 of the base. The configuration shown in FIG. 8 applies mutatis mutandis to the configuration of the cushion layer 70 and the configuration of the adhesive layer 60. When the cushion layer 70 is disposed between the dash panel 10 and the base sound absorbing layer 30, the cushioning performance of the cushion layer 70 suppresses vibration of the base sound absorbing layer 30 and attenuates sound emission due to vibration. Have. Therefore, the insulator dash 20A shown in FIG. 8 and FIG. 9 attenuates sound emission due to vibration of the sound absorbing layers 30 and 40 by attaching the cushion layer 70, and as is apparent from the graphs of FIG. 10 and FIG. There is an effect of improving sound insulation performance (decreasing transmitted sound).

Next, FIGS. 12 and 13 show a third embodiment of the present invention, and also in the third embodiment, the insulator dash 20B attached to the indoor surface side of the dash panel 10 is applied. The insulator dash 20B according to the third embodiment is characterized by adopting a configuration in which a low air-permeable skin layer 80 is incorporated, and the insulator dash 20B shown in FIG. 12 is low on the surface side of the second sound absorbing layer 40. The ventilation skin layer 80 is laminated. As the material of the low air-permeable skin layer 80, felt, synthetic fiber nonwoven fabric such as PET (polyester) fiber, fiber aggregate made of paper (pulp or the like) in fiber form, polyurethane foam or the like can be used. The low-air-permeable skin layer 80 has a thickness of 0.1 to 5 mm, a density of 0.01 to 1.0 g / cm ³ , and an air permeability of 1 to 25 cm ³ / cm ² · sec (measured value using a fragile tester). ) Is set.

  When the low-breathing skin layer 80 is laminated on the surface of the second sound-absorbing layer 40, the triple wall sound-insulating function of the dash panel 10, the resonance layer 50, and the low-breathing skin layer 80 is obtained, and the middle / high frequency range (630 Hz) The sound insulation and sound absorption performance of the above) can be improved. In addition, the low-breathing skin layer 80 also has an effect of preventing the second sound absorbing layer 40 from falling off.

  Furthermore, as the setting location of the low-air-permeable skin layer 80, it may be provided over the entire surface of the second sound-absorbing layer 40, but as shown in FIG. 13, only the upper portion 20a in the insulator dash 20B has a low-air-permeable skin layer. 80 may be set, and the lower portion 20b may be omitted. For example, the lower portion 20b may be locally provided only in a portion where sound absorption performance is desired to be improved. Although not shown, in addition to the basic configuration in which a non-breathable resonance layer 50 is interposed between the base sound absorbing layer 30 and the second sound absorbing layer 40, the surface of the second sound absorbing layer 40 is provided on the surface side. It is also possible to adopt a configuration in which the low air permeability skin layer 80 is laminated and the cushion layer 70 is appropriately incorporated inside.

14 to 16 show a fourth embodiment of the vehicle soundproofing material according to the present invention. Like the first to third embodiments described above, an insulator dash 20C attached to the interior surface side of the dash panel 10 is shown. Applicable. The insulator dash 20C according to the fourth embodiment is characterized in that a sound insulation sheet 90 is newly added, and the sound insulation sheet 90 is preferably made of a lightweight material in order to suppress an increase in weight as much as possible. The material may be a non-breathable material such as rubber, EPDM, foam sheet, or film, or a breathable material such as felt or nonwoven fabric. When using a breathable material, the surface density is in the range of 50 to 9000 g / m ² and the air flow rate is in the range of 0.5 to 10 cm ³ / cm ² · sec (measured by a fragile type tester). It is better to choose.

  Furthermore, in the insulator dash 20C, the sound insulation sheet 90 may be set on the entire surface of the product, or may be installed only on the portion where the sound insulation performance is desired to be improved as shown in FIGS. In FIG. 16, the partially set sound insulation sheets are encoded as 90A, 90B, and 90C, respectively.

  In the first to fourth embodiments described above, the present invention is applied to the insulator dashes 20 and 20A to 20C attached to the vehicle interior side of the dash panel 10, but the roof trim, floor carpet, and engine that are installed in the vehicle interior. It can be applied to various soundproofing materials installed in a room, luggage room, or trunk room. In addition, the soundproofing material represented by the insulator dash 20, 20A to 20C has a basic structure that includes at least two layers of the sound absorbing layer 30 and the resonance layer 50 as a basic structure, and the second sound absorbing layer 40 is included in this basic structure. Various variations may be imparted by appropriately assembling the cushion layer 70, the low air-permeable skin layer 80, and the sound insulation sheet 90.

It is sectional drawing which shows 1st Example which applied the soundproof material for vehicles which concerns on this invention to the insulator dash. It is sectional drawing which shows each structural member of the insulator dash shown in FIG. It is a graph which shows the relationship between the resonance layer in the insulator dash shown in FIG. 1, and sound insulation performance. It is a graph which shows the relationship between the resonance layer and sound absorption performance in the insulator dash shown in FIG. It is a graph which shows the relationship between the occupation area of the contact bonding layer in the insulator dash shown in FIG. 1, and sound insulation performance. It is a graph which shows the relationship between the occupation area of the contact bonding layer in the insulator dash shown in FIG. 1, and sound absorption performance. It is sectional drawing which shows the modification in 1st Example of the soundproof material for vehicles which concerns on this invention. It is sectional drawing which shows the structure of 2nd Example of the soundproof material for vehicles which concerns on this invention. It is sectional drawing which shows the modification of 2nd Example of the soundproof material for vehicles which concerns on this invention. It is a graph which shows the relationship between the cushion layer in the insulator dash shown in FIG. 8, and sound insulation performance. It is a graph which shows the relationship between the cushion layer in the insulator dash shown in FIG. 8, and sound absorption performance. It is sectional drawing which shows the structure of 3rd Example of the soundproof material for vehicles which concerns on this invention. It is a front view which shows the modification of 3rd Example of the soundproof material for vehicles which concerns on this invention. It is sectional drawing which shows the structure of 4th Example of the soundproof material for vehicles which concerns on this invention. It is sectional drawing which shows the modification of 4th Example of the soundproof material for vehicles which concerns on this invention. It is a front view which shows the modification of 4th Example of the soundproof material for vehicles which concerns on this invention. It is explanatory drawing which shows the installation location of the conventional insulator dash. It is sectional drawing which shows the structure of the conventional insulator dash. It is explanatory drawing which shows schematic structure of the sound insulation type insulator dash in the conventional insulator dash, and a ventilation type | mold insulator dash.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Dash panel 11 Floor carpet 12 Instrument panel 20, 20A, 20B, 20C Insulator dash 30 Base sound absorption layer 40 2nd sound absorption layer 50 Resonant layer 60 Adhesive layer 70 Cushion layer 80 Low ventilation skin layer 90, 90A, 90B, 90C sound insulation sheet

Claims (3)

A vehicle soundproofing material (20) mounted on the indoor surface side of the vehicle body panel (10), wherein the vehicle soundproofing material (20) transmits noise transmitted through the vehicle body panel (10) to the indoor side. At least one sound absorbing layer (30) that absorbs sound by function, and a resonance layer (50) integrated with the sound absorbing layer (30) in order to absorb noise propagating from the sound absorbing layer (30) by resonance action In the vehicle soundproofing material (20) provided at least,
The resonance layer (50) has a thickness in the range of 0.01 to 5 mm and a maximum bending load in the range of 0.001 to 1 N , and the sound absorbing layer (30) and the resonance layer (50). Are integrated by an adhesive layer (60) having an occupied area of 0 to 50% with respect to the entire joint surface of both ,
Wherein the backing layer (30) and the surface side of the resonant layer (50) from become laminate bonding surface of at least one second sound absorbing layer (40) is resonant layer (50) a backing layer (40) resonance action between the Rukoto are integrated via an adhesive layer (60) having an area occupied by 0-50% with respect to the entire surface, the base of the backing layer (30) and the second sound absorbing layer (40) A resonant layer (50) comprising :
A vehicle soundproofing material , wherein a low-breathing skin layer (80) is bonded and fixed to a surface side of the at least one second sound-absorbing layer (40). A cushion layer (70) is interposed on either one of the front and back surfaces of the resonance layer (50) or at least one side between the sound absorption layer (30) of the base and the vehicle body panel (10). The vehicle soundproofing material according to claim 1 . The soundproofing material for vehicles according to claim 1 or 2 , wherein a soundproofing sheet (90) is set on a room facing surface of the soundproofing material (20).

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