JPH10226006A - Sound-insulating structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound-insulating structure having a shaped sound- absorbing layer following the shape of a partition wall and capable of suppressing the transmitted sound from the partition wall and capable of preventing lowering of sound absorbing and insulating capacity. SOLUTION: In a sound-insulating structure provided on one surface of a dash panel 1 and formed by integrally laminating a skin layer 10 and a molded sound-absorbing layer A, the molded sound-absorbing layer A is formed by providing a sound-absorbing layer 11 rich in sound absorbing properties on an indoor side and providing the shaped sound absorbing layer 12 following the surface shape of the dash panel 1 on the inner surface side of the dash panel 1 to successively integrally laminate the skin layer 10, the sound absorbing layer 11 and the shape sound absorbing layer 12 in this order from the indoor side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound insulating structure suitable for an automotive dash, an insulator floor, etc., which is mounted on a dash panel.

[0002]

2. Description of the Related Art For example, as shown in FIG. 8, a vehicle compartment R of a dash panel 1 for partitioning an engine compartment E and a vehicle compartment R.
An insulator dash 2 is installed on the inner surface of the vehicle to prevent the propagation of noise from the engine room E to the vehicle room R.

The insulator dash 2 generally uses a laminated structure of a skin layer 3 as shown in FIG. 9 and a sound absorbing layer 4 made of a porous base material such as felt, polyurethane foam, nonwoven fabric, or the like.

The sound absorbing layer 4 absorbs noise from the engine room E, and has a double-walled sound insulating effect with the dash panel 1 so as to exhibit soundproofing characteristics.

[0005]

However, in the above-described conventional sound insulation structure, when the dash panel 1 has a plurality of convex beads 5, the sound absorbing layer 4 follows the shape of the dash panel 1. That is, as shown in FIGS. 9 and 10, the bend of the sound absorbing layer 4 cannot follow the corner 5A of the bead 5, and a gap (air layer) between the corner 5A of the bead 5 and the sound absorbing layer 4 cannot be formed. ) 6 is generated, and the transmitted sound A from the dash panel 1 reaches the sound absorbing layer 4 through the gap (air layer) 6 and a portion where no gap exists between the dash panel 1 and the sound absorbing layer 4. There is a propagation path for the transmitted sound a from the dash panel 1 to reach the sound absorbing layer 4 directly, so that the transmitted sound a from the dash panel 1 cannot be suppressed, and the absorption and sound insulation performance must be reduced. There was a problem.

The present invention has been made in view of the above-mentioned problems. An object of the present invention is to form a shaped sound absorbing layer so as to follow the shape of the partition wall and to transmit light from the partition wall. It is an object of the present invention to provide a sound insulation structure capable of suppressing sound and preventing a decrease in sound absorption and sound insulation performance.

[0007]

In order to achieve the above object, a sound insulating structure according to the present invention is provided on one side of a partition wall, and a skin layer and a molded sound absorbing layer are integrally laminated. In the sound insulation structure formed as described above, a portion of the molded sound absorbing layer along one surface side of the partition is a shaped sound absorbing layer that follows the surface shape of the partition.

With this configuration, even if the partition has a plurality of convex beads, the shaped sound absorbing layer follows the shape of the partition. That is, the bend of the shaped sound absorbing layer follows the corner of the bead, and a gap (air layer) is formed between the corner of the bead and the shaped sound absorbing layer.
No longer occurs, and the transmitted sound from the partition walls
There is no propagation path that reaches the shaped sound absorbing layer through the structure, and all the transmitted sound from the bulkhead becomes a propagation path that directly reaches the shaped sound absorbing layer, and the transmitted sound from the bulkhead can be suppressed, and the sound absorption and sound insulation can be suppressed. Performance degradation can be prevented.

According to another aspect of the present invention, there is provided a sound insulating structure according to the first aspect of the present invention, wherein the molded sound absorbing layer has a sound absorbing property on the indoor side. A sound absorbing layer is provided, and a shaped sound absorbing layer that follows the surface shape of the partition is provided on the inner surface side of the partition, and the skin layer, the sound absorbing layer, and the shaped sound absorbing layer are laminated in this order from the indoor side. It has become.

With this configuration, not only can the same effect as the above-described invention of claim 1 be achieved, but also the sound absorbing layer on the indoor side can more effectively exhibit sound absorbing and sound insulating performance.

In order to achieve the above object, a sound insulating structure according to a third aspect of the present invention is the sound insulating structure according to the first aspect, wherein the molded sound absorbing layer has a shape-forming property on the indoor side. Providing a first shaped sound absorbing layer having, on the inner surface side of the partition wall,
Providing a second shaped sound absorbing layer that follows the surface shape of the partition,
An intermediate sound absorbing layer rich in sound absorption is provided between the first shaped sound absorbing layer and the second shaped sound absorbing layer, and the skin layer and the first shaped sound absorbing layer are provided from the indoor side. The intermediate sound absorbing layer and the second shaped sound absorbing layer were laminated and integrated in this order.

According to this structure, not only can the same effect as the above-mentioned invention of claim 1 be exerted, but also the sound absorbing layer on the skin layer side can be formed as the first shaped sound absorbing layer which is rich in shapeability. The mass (mass) of the skin layer plus the first shaped sound absorbing layer is formed, and the sound insulation performance is further improved by the mass effect of the double wall.

[0013] In order to achieve the above object, a sound insulation structure according to the invention of claim 4 provides a sound insulation structure according to claim 2 or 3.
In the sound insulation structure according to the above, the material composition of the molded sound absorbing layer is a linear or crimped thermoplastic synthetic resin fiber,
A heat-fusible fiber serving as a binder, and in the material composition of the shaped sound-absorbing layer, the mixing ratio of at least the heat-fusible fiber was increased and the areal density was reduced as compared with the material composition of the sound-absorbing layer. .

With this configuration, it is possible to realize that the shaped sound absorbing layer follows the shape of the partition. Therefore, an operation similar to the operation of the first aspect of the invention can be achieved.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1 FIGS. 1 to 4 show a sound insulating structure (Embodiment 1) according to the present invention. FIG. 1 is a cross-sectional view of a sound insulating structure (Embodiment 1) according to the present invention, FIG. 2 is an enlarged cross-sectional view of the sound insulating structure (Embodiment 1), and FIG. FIG. 4 is a configuration diagram of a manufacturing apparatus in which a sound absorbing layer and a shaped sound absorbing layer are each used as a nonwoven fabric and have a multilayer structure by a card method.

The insulator dash 2 as a sound insulating structure according to the first embodiment of the present invention has a relatively low surface density such as a vinyl chloride sheet or a rubber sheet mixed with a filler having a high specific gravity as shown in FIG. A large skin layer 10, a sound-absorbing layer 11 that is crimped and integrated on the back side of the skin layer 10, and a shaped sound-absorbing layer 12 that is bonded to the sound absorbing layer 11.

The skin layer 10, the sound-absorbing layer 11, and the shaped sound-absorbing layer 12 are formed into a required shape by cold press molding to form a formed sound-absorbing layer A.
Is fixed to the dash panel 1 as a partition wall by a fixing means such as a clip (not shown).

The feature of the present invention is that a sound absorbing layer 11 which emphasizes sound absorbing properties is provided on the indoor side, and a shaped sound absorbing layer which has flexibility on the inner surface side of the vehicle compartment of the dash panel 1 and emphasizes shaping. A layered structure is provided in which a layer 12 is provided, and a skin layer 10, a sound absorbing layer 11, and a shaped sound absorbing layer 12 are laminated and integrated in this order from the indoor side, and a molded sound absorbing layer A has two layers.

The sound-absorbing layer 11 is made of a material having excellent sound-absorbing / vibrating performance, and is made of a linear or crimped thermoplastic synthetic resin fiber (fiber diameter: 2 denier or more, surface density: 350 to 14).
00 g / m ² ), 50 to 85 parts by weight, and heat-fusible fiber (fiber diameter: 2 denier or more, area density: 35) serving as a binder
0 to 1400 g / m ² ) by weight of 50 to 15 g / cm ²
And a material configuration obtained by mixing

Nylon, polyacrylonitrile, polyacetate, polyethylene terephthalate, etc. are used for the thermoplastic synthetic resin fiber as a material composition having excellent sound absorption / vibration performance, and polyethylene, polypropylene is used for the heat fusible fiber. , Linear polyester, polyamide and the like are used.

The shaped sound absorbing layer 12 is a material having excellent shaping performance, and is made of a linear thermoplastic synthetic resin fiber (fiber diameter: 2 denier or more, surface density: 50 to 200 g / m ² ).
And heat-fusible fibers (fiber diameter: 2 denier or more, areal density; 50 to 200) by weight 70 to 100
Or a linear thermoplastic synthetic resin fiber (fiber diameter; 2 denier or more, areal density; 50 to 2)
00g / m ² ) by weight of 40 to 0 and crimped thermoplastic synthetic resin fiber (fiber diameter: 2 denier or more, areal density: 50
To 200 g / m ² ) by weight of 40 to 70 and a heat-fusible fiber (fiber diameter: 2 denier or more, areal density: 50 to 200 g)
/ M ² ) and 20 to 30 parts by weight.

As the material configuration for forming the shaped sound absorbing layer 12 having excellent shaping performance, the same material configuration as that for forming the above-described sound absorbing layer 11 having excellent sound absorbing and vibration performance can be used.

The material constitutions of the above-mentioned sound absorbing layer 11 and shaped sound absorbing layer 12 are shown in Table 1.

[Table 1]

As can be seen from Table 1, the shaped sound absorbing layer 12
In the material configuration having excellent shaping performance for forming the heat-absorbing layer 11, the blending ratio of the heat-fusible fibers is larger than that of the material configuration of the sound absorbing layer 11, and the areal density is reduced. Further, the blending ratio of the crimped thermoplastic synthetic resin fiber may be increased. By adopting such a material configuration, the shaping performance is excellent, and the shape followability (fitness) to the dash panel 1 is enhanced.

Therefore, in the sound insulation structure according to the present invention, the shaped sound absorbing layer 12 follows the shape of the dash panel 1 even if the dash panel 1 has a plurality of convex beads 5. That is, as shown in FIG. 3, the bend of the shaped sound absorbing layer 12 follows the corner 5A of the bead 5, and no gap (air layer) is formed between the corner 5A of the bead 5 and the shaped sound absorbing layer 12. There is no propagation path for the transmitted sound a from the dash panel 1 to reach the shaped sound absorbing layer 12 through the gap (air layer), and the transmitted sound a from the dash panel 1 directly reaches the shaped sound absorbing layer 12. It becomes a propagation path, so that the transmitted sound a from the dash panel 1 can be suppressed, and the absorption and sound insulation performance can be prevented from lowering.

Further, the sound insulating structure according to the present invention uses the sound absorbing layer 11 and the shaped sound absorbing layer 12 as nonwoven fabrics, respectively, and can be easily formed into a multilayer structure by a card system. That is, as an example, as shown in FIG. 4, a thermoplastic synthetic resin fiber and a heat-fusible fiber which are the materials of the shaped sound absorbing layer 12 are formed on the first card 50 by a linear thermoplastic synthetic resin. Resin fiber (fiber diameter; 2 denier or more, areal density; 50
To 200 g / m ² ) in a ratio of 30 to 0 parts by weight and a heat-fusible fiber (fiber diameter: 2 denier or more, areal density; 50 to 200) in a ratio of 70 to 100 parts by weight. The first nonwoven fabric 51 is supplied from the first card 50 onto the conveyor 60 in a bulky manner.

Then, the sound absorbing layer 11 is provided on the second card 52.
The thermoplastic synthetic resin fiber and the heat-fusible fiber which are the raw materials of the above are made of a thermoplastic synthetic resin fiber having a linear or crimped shape (fiber diameter: 2 denier or more, areal density: 350 to 1400).
g / m ² ) to 50 to 85 parts by weight and heat-fusible fibers (fiber diameter: 2 denier or more, areal density: 350 to 1400 g / m
² ) The weight ratio is changed to 50 to 15 parts by weight, and then supplied from the second card 52 so as to be laminated on the upper surface of the nonwoven fabric mat 51 supplied from the first card 50 to form a nonwoven fabric mat 53. I do.

The nonwoven fabric mats 51 and 53 are punched by a needle punching machine 61 and heated by a hot air heating furnace 62 to melt the heat-fusible fibers. After that,
It is cut into a predetermined size to obtain a laminated nonwoven fabric mat M which is a material of the sound absorbing layer used in the present invention.

After that, the laminated nonwoven fabric mat M is heated and softened by a hot air heating furnace (not shown), and then cold pressed, formed into a shape conforming to the shape of the dash panel 1, and formed and absorbed by the insulator dash 2. The formation of the layer A is completed.

The sound absorbing layer 11 and the shaped sound absorbing layer 12 may be integrated by a method in which the sound absorbing layer 11 and the shaped sound absorbing layer 12 are formed in separate steps, respectively, and then they are bonded together.

Embodiment 2 FIGS. 5 to 7 show a sound insulating structure (Embodiment 2) according to the present invention. FIG. 5 is a cross-sectional view of the sound insulating structure (Embodiment 2) according to the present invention, FIG. 6 is an enlarged cross-sectional view of the sound insulating structure (Embodiment 1), and FIG. FIG.

The sound insulation structure according to Embodiment 2 of the present invention is provided with a first shaped sound absorbing layer 22 emphasizing shaping on the indoor side as shown in FIGS. A second shaped sound absorbing layer 20 having flexibility and emphasis on shaping is provided on the inner surface, and a sound absorbing property is provided between the first shaped sound absorbing layer 22 and the second shaped sound absorbing layer 20. Is provided, and the skin layer 10, the first shaped sound absorbing layer 22, the intermediate shaped sound absorbing layer 23, and the second shaped sound absorbing layer 20 are laminated and integrated in this order from the indoor side. The molded sound absorbing layer A has three layers.

The first shaped sound absorbing layer 22 is a material having excellent shaping performance, and is made of a linear thermoplastic synthetic resin fiber (fiber diameter: 2 denier or more, surface density: 50 to 200 g / m ² ).
And a heat-fusible fiber (fiber diameter: 2 denier or more, areal density: 50 to 200 g / m ² ) by weight 70
-100, or a linear thermoplastic synthetic resin fiber (fiber diameter; 2 denier or more, areal density;
50 to 200 g / m ² ), 40 to 70 parts by weight of a crimped thermoplastic synthetic resin fiber (fiber diameter: 2 denier or more, areal density; 50 to 200 g / m ² ); Fusible fiber (fiber diameter; 2 denier or more, areal density;
200 g / m ² ) and 20 to 30 parts by weight.

Nylon, polyacrylonitrile, polyacetate, polyethylene terephthalate and the like are used for the thermoplastic synthetic resin fiber, and polyethylene, polypropylene, linear polyester, polyamide and the like are used for the heat fusible fiber. You.

The intermediate sound-absorbing layer 23 is made of a material having excellent sound-absorbing performance, and is made of a linear or crimped thermoplastic synthetic resin fiber (fiber diameter: 2 denier or more, surface density: 300 to
1,200 g / m ² ), 50 to 85 parts by weight, heat-fusible fiber (fiber diameter: 2 denier or more, area density: 300 to 120)
0 g / m ² ) and 50 to 15 parts by weight.

The second shaped sound absorbing layer 20 is made of a material having excellent shaping performance, and is made of a linear thermoplastic synthetic resin fiber (fiber diameter: 2 denier or more, surface density: 50 to 200 g / m ² ).
And a heat fusible fiber (fiber diameter: 2 denier or more, areal density; 50 to 200 g / m ² ) by weight 70
-100, or a linear thermoplastic synthetic resin fiber (fiber diameter; 2 denier or more, areal density;
50 to 200 g / m ² ), 40 to 70 parts by weight of a crimped thermoplastic synthetic resin fiber (fiber diameter: 2 denier or more, areal density; 50 to 200 g / m ² ); Fusible fiber (fiber diameter; 2 denier or more, areal density;
200 g / m ² ) and 20 to 30 parts by weight.

The material configuration for forming the first and second shaped sound absorbing layers 22 and 20 and having excellent shaping performance is the same as the material configuration for forming the intermediate sound absorbing layer 23 and having excellent sound absorbing and vibration performance. Can be used.

The material configurations of the first shaped sound absorbing layer 22, the intermediate sound absorbing layer 23 and the second shaped sound absorbing layer 20 are shown in Table 2 below.
Shown in

[Table 2]

As can be seen from Table 2, the composition of the material having excellent shaping performance for forming the second shaped sound absorbing layer 20 is higher than the material composition of the intermediate sound absorbing layer 23 in the mixing ratio of the heat-fusible fiber. And the area density is reduced. Further, the blending ratio of the crimped thermoplastic synthetic resin fiber may be increased. By adopting such a material configuration, the shaping performance is excellent, and the shape followability (fitness) to the dash panel 1 is enhanced.

Therefore, in the sound insulating structure according to the second embodiment of the present invention, even if the dash panel 1 has a plurality of convex beads 5, the second shaped sound absorbing layer 20 has the dash panel. Follow the shape of No. 5. That is, as shown in FIG. 7, the bend of the second shaped sound absorbing layer 20 follows the corner 5A of the bead 5, and the gap (between the corner 5A of the bead 5 and the second shaped sound absorbing layer 20) is formed. Air layer) is no longer generated, and the transmitted sound b from the dash panel 1 passes through the gap (air layer)
There is no propagation path reaching the shaped sound absorbing layer 20 of FIG. 2, and the transmitted sound a from the dash panel 1 becomes the propagation path directly reaching the second shaped sound absorbing layer 20, and the transmitted sound a Can be suppressed, and a decrease in absorption and sound insulation performance can be prevented.

As described above, the intermediate sound absorbing layer 23
The material configuration is excellent in sound absorption / vibration performance, and the first and second shaped sound absorbing layers 22 and 20 are excellent in shape followability and excellent in shapeability. By making the sound absorbing layer on the skin layer 10 side, that is, the first shaped sound absorbing layer 22 rich in shaping properties, the mass (mass) of the skin layer 10 plus the first shaped sound absorbing layer 22 is reduced. Due to the mass effect of the formed double wall, the sound insulation performance is further improved.

As described in the first embodiment, the sound insulating structure according to the second embodiment of the present invention includes the first and second shaped sound absorbing layers 22 and 20 and the intermediate sound absorbing layer. 23 can be easily formed into a multilayer structure by a card system. Each of the first and second shaped sound-absorbing layers 22 and 20 and the intermediate sound-absorbing layer 23 can be formed by the first method. Alternatively, the shaped sound absorbing layer 22, the intermediate sound absorbing layer 23, and the second shaped sound absorbing layer 20 may be formed in separate steps, and then bonded together.

[0044]

As described above, according to the sound insulation structure according to the first aspect of the invention, the sound insulation structure provided on one surface side of the partition wall and integrally integrating the skin layer and the molded sound absorption layer. In, by forming a portion of the molded sound absorbing layer along one surface side of the partition wall as a shaped sound absorbing layer that follows the surface shape of the partition wall, even if the partition wall has a plurality of convex beads,
The shaped sound absorbing layer follows the shape of the partition. That is, the bend of the shaped sound absorbing layer follows the corner of the bead, and no gap (air layer) is formed between the corner of the bead and the shaped sound absorbing layer. ), There is no propagation path to the shaped sound absorbing layer, and all of the transmitted sound from the partition walls becomes a propagation path directly to the shaped sound absorbing layer, and the transmitted sound from the partition walls can be suppressed. A decrease in sound insulation performance can be prevented.

According to a second aspect of the present invention, in the sound insulating structure according to the first aspect, the molded sound absorbing layer is provided with a sound absorbing layer having a high sound absorbing property on the indoor side, and the partition wall is provided. By providing a shaped sound absorbing layer that follows the surface shape of the partition wall on the inner surface side of the above, the skin layer, the sound absorbing layer, and the shaped sound absorbing layer were laminated and integrated in the order from the indoor side, thereby providing the above-described structure. Not only the same effect as the effect of the first aspect of the invention can be achieved, but also the sound absorbing layer on the indoor side can more effectively exhibit sound absorbing and sound insulating performance.

According to a third aspect of the present invention, in the sound insulating structure according to the first aspect, the shaped sound absorbing layer has a first shaped sound absorbing layer having a shape forming property on the indoor side. A second shaped sound absorbing layer that follows the surface shape of the partition wall on the inner surface side of the partition wall, and is provided between the first shaped sound absorbing layer and the second shaped sound absorbing layer. Providing an intermediate sound-absorbing layer rich in sound-absorbing properties, and laminating and integrating the skin layer, the first shaped sound-absorbing layer, the intermediate shaped sound-absorbing layer, and the second shaped sound-absorbing layer in this order from the indoor side. In addition to providing the same effect as the above-described effect of the first aspect of the present invention, the sound absorbing layer on the skin layer side is formed into a first shaped sound absorbing layer having a good shaping property, whereby The mass of the layer plus the first shaped sound absorbing layer is formed, and the sound insulation performance is further improved by the mass effect of the double wall. To become.

According to a fourth aspect of the present invention, in the sound insulating structure according to the second or third aspect, the molded sound absorbing layer has a linear or crimped thermoplastic material composition. Synthetic resin fibers, comprising a heat-fusible fiber serving as a binder, in the material configuration of the shaped sound absorbing layer,
By increasing the mixing ratio of the heat-fusible fibers and decreasing the areal density at least as compared with the material configuration of the sound absorbing layer, the shaped sound absorbing layer can follow the shape of the partition wall. Therefore, the same effect as the effect of the first aspect of the invention can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a sound insulation structure (first embodiment) according to the present invention.

FIG. 2 is an enlarged sectional view of the sound insulation structure (Embodiment 1).

FIG. 3 is an enlarged view of a portion F in FIG. 1;

FIG. 4 is a configuration diagram of a manufacturing apparatus in which a sound absorbing layer and a shaped sound absorbing layer are each used as a nonwoven fabric and have a multilayer structure by a card method.

FIG. 5 is a sectional view of a sound insulating structure (Embodiment 2) according to the present invention.

FIG. 6 is an enlarged sectional view of the sound insulation structure (Embodiment 1).

FIG. 7 is an enlarged view of a portion G in FIG. 5;

FIG. 8 is an explanatory diagram of an insulator dash installed on an inner surface of a vehicle compartment of a dash panel that partitions an engine room and a vehicle compartment.

FIG. 9 is a cross-sectional view of a conventional sound insulation structure.

FIG. 10 is an enlarged view of a portion H in FIG. 9;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 dash panel (partition wall) 10 skin layer 11 sound absorbing layer 12 shaped sound absorbing layer 20 second shaped sound absorbing layer 22 first shaped sound absorbing layer 23 intermediate sound absorbing layer A shaped sound absorbing layer

Claims (4)

[Claims] In a sound insulation structure provided on one surface side of a partition wall and integrally laminating a skin layer and a molded sound absorbing layer, a portion of the molded sound absorbing layer along one surface side of the partition wall is formed by the above-mentioned method. A sound-insulating structure, characterized in that the shaped sound-absorbing layer follows the surface shape of the partition. 2. The molded sound-absorbing layer is provided with a sound-absorbing layer rich in sound-absorbing properties on the indoor side, and a shaped sound-absorbing layer following the surface shape of the partition on the inner side of the partition. The sound insulation structure according to claim 1, wherein the layers, the sound absorbing layer, and the shaped sound absorbing layer are laminated and integrated in this order. 3. The shaped sound absorbing layer has a first shaped sound absorbing layer having shapeability on the indoor side, and a second shaped sound absorbing layer that follows the surface shape of the partition wall on the inner surface side of the partition wall. A first sound-absorbing layer provided between the first shaped sound-absorbing layer and the second shaped sound-absorbing layer. The sound insulation structure according to claim 1, wherein the sound absorbing layer, the intermediate sound absorbing layer, and the second shaped sound absorbing layer are laminated and integrated in this order. 4. A material structure of said shaped sound absorbing layer, wherein said material structure of said molded sound absorbing layer comprises a linear or crimped thermoplastic synthetic resin fiber and a heat fusible fiber serving as a binder. The sound insulation structure according to claim 2 or 3, wherein at least the mixing ratio of the heat-fusible fibers is increased and the areal density is reduced as compared with the material configuration of the layer.