JP2018202931A - Sound insulation structure - Google Patents

Abstract

To provide a sound insulation structure which enables improvement of acoustic insulation while inhibiting weight and cost increase.SOLUTION: A sound insulation structure includes: a mass part 11 which is disposed at a spacing from an outer panel 5 partitioning an internal space from an external space of a vehicle body and has a planar shape in at least a part thereof; and multiple spring parts 12 which are disposed at the side facing the outer panel 5 in the mass part 11. The spring part 12 has: a hollow film material 14 having airtightness and flexibility; and a gas 15 enclosed in the film material 14.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a sound insulation structure.

  In vehicles such as automobiles and buildings, the partition member that partitions the exterior and interior space has sound insulation performance in order to prevent the intrusion of noise from the exterior to the interior space or the leakage of noise from the interior space to the exterior. Providing a sound insulation material.

  For example, Patent Document 1 discloses a configuration in which a spacer having a plurality of recesses is disposed as a sound insulating material between a partition member (roof board) and a porous base material on the inner space side. According to such a configuration, the noise (sound wave) that has entered from the partition member side enters the recess formed in the spacer, and is reflected in the recess, thereby exhibiting sound insulation performance.

  Patent Document 2 discloses a configuration in which a urethane layer is placed as a sound insulating material on a partition member (vehicle floor board), and noise is attenuated by this urethane layer to exhibit sound insulation. Further, in this configuration, a sound insulation structure is provided in which a mass layer is used as a mass and a urethane layer is used as a spring by placing a plate-like mass layer on the urethane layer.

  Patent Document 3 discloses a configuration in which a sound insulating material made of a porous foam material or a fiber material is disposed in a bag formed of a film, and a sealing gas is sealed in the bag.

JP 2010-265589 A JP 2003-104135 A JP 2006-123614 A

  Incidentally, it is always desired to further improve the sound insulation. For example, in an automobile, a material for forming an outer panel of a vehicle body may be replaced with an aluminum-based material or a resin-based material from an iron-based material in order to improve a fuel consumption rate by reducing the weight of the vehicle. Then, the sound insulation in the outer panel itself may be lowered, and it is required to further improve the sound insulation.

However, in the conventional techniques disclosed in Patent Documents 1 to 3, any attempt to further improve the sound insulation properties requires an increase in the thickness of the sound insulation material. However, when the thickness of the sound insulating material increases, an increase in the amount of use of the sound insulating material causes an increase in weight and cost.
This invention is made | formed in view of the said situation, and it aims at providing the sound insulation structure which can improve sound insulation, suppressing a weight increase and a raise of cost.

As a means for solving the above problems, the invention (sound insulation structure) described in claim 1 is characterized in that the internal space (for example, the internal space 3 of the embodiment) and the outside (for example, the external of the embodiment) of the structure (for example, the vehicle body 1 of the embodiment). 4) a mass portion (for example, mass portion 11 according to the embodiment) which is arranged at a distance from a partition member (for example, the outer panel 5 and the inner panel 6 according to the embodiment) and has a planar shape at least partially. And a plurality of spring portions (for example, the spring portion 12 of the embodiment) arranged on the side facing the partition member in the mass portion, and the spring portion is a hollow having airtightness and flexibility. It has a film material (for example, the film material 14 of the embodiment) and a gas (for example, the gas 15 of the embodiment) enclosed in the film material.
According to a second aspect of the present invention, in the sound insulation structure according to the first aspect, a sound insulation member (for example, the sound insulation member 10 of the embodiment) including the mass portion and the spring portion is formed, and the sound insulation member is It further includes a bonding layer member (for example, the bonding layer member 13 of the embodiment) that is provided on the side of the spring portion facing the partition member and can be bonded to the partition member.
According to a third aspect of the present invention, in the sound insulation structure according to the second aspect, the mass portion is made of polypropylene, the film material is made of an ethylene-vinyl alcohol copolymer, and the bonding layer member is made of polyethylene. It is characterized by comprising.
According to a fourth aspect of the present invention, in the sound insulating structure according to any one of the first to third aspects, the mass portion is formed of a material having a specific gravity greater than that of the film material of the spring portion. It is characterized by that.
According to a fifth aspect of the present invention, in the sound insulation structure according to any one of the first to fourth aspects, the film material of the spring portion is formed of a material having a Young's modulus lower than that of the mass portion. It is characterized by that.
According to a sixth aspect of the present invention, in the sound insulation structure according to any one of the first to fifth aspects, the plurality of spring portions are spaced from each other in a direction along a facing surface facing the partition member. It is characterized by being arranged.
The invention according to claim 7 is the sound insulation structure according to any one of claims 1 to 6,
The gas is air.
The invention described in claim 8 is the sound insulation structure according to any one of claims 1 to 6, wherein the gas is carbon dioxide or helium.
The invention according to claim 9 is the sound insulation structure according to any one of claims 1 to 8, wherein the structure is a vehicle body (for example, the vehicle body 1 of the embodiment), and the partition member is the It is an outer panel of the vehicle body (for example, the outer panel 5 of the embodiment) or an inner panel (for example, the inner panel 6 of the embodiment) that forms the interior of the vehicle body.

According to the first aspect of the present invention, it is possible to configure a sound insulation structure in which the mass portion is the mass and the spring portion is the spring. Therefore, by appropriately adjusting the mass of the mass portion and the spring constant of the spring of the spring portion, the frequency at which the mass portion resonates with respect to noise can be adjusted, and noise in the target frequency range can be efficiently suppressed.
Furthermore, since the sound insulation structure has a structure in which a gas is sealed inside a hollow membrane material, the amount of material used to form the membrane material is significantly less than that of the urethane layer. Therefore, even if the thickness of the sound insulation structure in the direction in which the mass portion and the partition member face each other is increased, the sound insulation can be improved while suppressing an increase in weight and cost.
According to the second aspect of the present invention, the sound insulation member is constituted by the mass portion and the spring portion, and in this sound insulation member, the bonding layer member is provided on the side of the spring portion facing the compartment member, thereby providing the compartment member. On the other hand, the sound insulation structure can be joined by the joining layer member, and the sound insulation structure can be easily provided on the partition member.
According to the invention described in claim 3, high formability can be obtained by forming the mass portion with polypropylene. Further, by forming the film material with an ethylene-vinyl alcohol copolymer, high airtightness can be obtained, and leakage of the gas enclosed in the film material can be suppressed. Furthermore, by forming the joining layer member from polyethylene, it is possible to easily and reliably join the partition member.
According to the invention described in claim 4, by making the specific gravity of the mass portion larger than the specific gravity of the membrane material, the function as the mass of the mass portion can be effectively exhibited.
According to the invention described in claim 5, since the Young's modulus of the film material is made lower than the Young's modulus of the mass portion, the spring portion is easily elastically deformed, and noise can be efficiently suppressed.
According to the invention described in claim 6, the plurality of spring portions are provided so as to be spaced apart from each other in the direction along the facing surface, so that the mass portion is displaced so as to be contacted and separated toward the partition member side. Accordingly, when the spring portion is elastically deformed, it is possible to suppress the adjacent spring portions from buffering. Thereby, it can suppress that another spring part inhibits a deformation | transformation of a spring part, and can suppress a noise efficiently.
According to the seventh aspect of the present invention, the mass portion and the membrane material are integrally formed, so that it is not necessary to separately join the mass portion and the membrane material, and the sound insulation member is efficiently manufactured. be able to.
According to the seventh aspect of the present invention, the cost can be reduced by using air as the gas enclosed in the membrane material.
According to the invention described in claim 8, by using carbon dioxide as the gas enclosed in the membrane material, the sound speed (sound wave propagation speed) is lower than in the air, and the sound insulation performance can be improved. Further, by using helium as the gas sealed in the film material, the density becomes lower than that of air, and the sound insulation performance can be improved.
According to the ninth aspect of the present invention, the sound insulation in the interior space of the vehicle body can be enhanced by providing the sound insulation structure as described above on the outer panel or the inner panel of the vehicle body of the automobile.

It is a longitudinal cross-sectional view which shows the roof part of the vehicle body provided with the sound insulation structure which concerns on embodiment of this invention. It is the perspective view which looked at the above-mentioned roof part from the car outside. It is sectional drawing which shows the sound insulation structure which concerns on embodiment of this invention. It is a top view which shows arrangement | positioning of the spring part in the said sound insulation structure. It is the figure which modeled the said sound insulation structure. It is a longitudinal cross-sectional view which shows the roof part of the vehicle body provided with the sound insulation structure which concerns on the 1st modification of embodiment of this invention. It is sectional drawing of the sound insulation structure which concerns on the 1st modification of embodiment of this invention. It is a longitudinal cross-sectional view which shows the roof part of the vehicle body provided with the sound insulation structure which concerns on the 2nd modification of embodiment of this invention. It is sectional drawing of the sound-insulation structure which concerns on the 3rd modification of embodiment of this invention. It is a top view which shows arrangement | positioning of the spring part in the sound insulation structure which concerns on the 3rd modification of embodiment of this invention. It is a top view which shows arrangement | positioning of the spring part in the sound insulation structure which concerns on the 4th modification of embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a roof portion of a vehicle body having a sound insulation structure to which an embodiment of the present invention is applied. FIG. 2 is a perspective view of the roof portion as viewed from the outside of the vehicle.

  As shown in FIGS. 1 and 2, the sound insulation structure according to this embodiment includes a sound insulation member 10. The sound insulation member 10 faces the outer panel (partition member) 5 of the roof part constituting the vehicle body (structure) 1 of the automobile and the inner space 3 in the vehicle body 1 to form the interior panel (roof garnish, partition member). ) 6. The sound insulation member 10 is fixed to the lower surface of the outer panel 5.

  As shown in FIG. 3, the sound insulating member 10 includes a mass portion 11, a spring portion 12, and a bonding layer member 13. The sound insulation member 10 is disposed in a space between the outer panel 5 and the inner panel 6.

  The mass portion 11 is, for example, a plate shape, and is disposed with a space from the outer panel 5 that partitions the internal space 3 and the exterior 4 (see FIG. 1) of the vehicle body 1. The mass portion 11 is preferably formed from, for example, polypropylene (PP). The mass portion 11 is preferably formed of a material having a higher specific gravity than a film material 14 of the spring portion 12 described later and having high moldability. As a material for forming such a mass portion 11, for example, polypropylene (PP) is preferably used. The mass portion 11 is not limited to a plate shape, and may be a member having a planar shape at least partially.

A plurality of spring portions 12 are arranged along the facing surface on the side facing the outer panel 5 in the mass portion 11. As shown in FIG. 4, in this embodiment, the spring portions 12 are arranged in a staggered manner along the mass portion 11.
Each spring portion 12 includes a hollow membrane material 14 and a gas 15 sealed inside the membrane material 14.

  The film material 14 has a cylindrical shape that extends in the direction in which the mass portion 11 and the outer panel 5 face each other. The membrane material 14 includes, for example, a cylindrical portion 14a having a circular cross-section when viewed from the direction in which the mass portion 11 and the outer panel 5 face each other, an end portion on the mass portion 11 side of the cylindrical portion 14a, and the bonding layer member 13 side. It forms the airtight container shape which was integrally provided with the edge part obstruction | occlusion part 14b which obstruct | occludes each edge part. The film material 14 is formed of a material having airtightness and flexibility. The film material 14 is preferably formed of a material having a Young's modulus lower than that of the material forming the mass portion 11 so as to be more elastically deformed than the mass portion 11. As a material for forming such a film material 14, for example, an ethylene-vinyl alcohol copolymer (for example, “Eval (trade name)” manufactured by Kuraray Co., Ltd.) is preferably used. "Is not limited to the one that forms a closed space where air does not enter and exit completely, and some air can enter and exit to such an extent that the membrane material 14 can function as a spring portion.

The gas 15 is filled in the hollow membrane material 14 at a pressure higher than a preset pressure so that at least the slackness of the membrane material 14 is eliminated.
As such a gas 15, for example, air can be used. Further, as the gas 15, carbon dioxide or helium can also be used.

The bonding layer member 13 is provided on the side of the spring portion 12 that faces the outer panel 5. In this embodiment, the bonding layer member 13 has a film shape and is formed so as to cover the plurality of spring portions 12.
Such a bonding layer member 13 is formed of a material that can be bonded to the outer panel 5. In this embodiment, the bonding layer member 13 is bonded to the outer panel 5 by welding using ultrasonic waves, heat, or the like. For this reason, it is preferable to form the joining layer member 13 with the material which is excellent in the weldability with respect to the outer panel 5. FIG. As a material for forming such a bonding layer member 13, for example, polyethylene (PE) can be used. The joining layer member 13 may be joined to the outer panel 5 with an adhesive layer or an adhesive.

  The bonding layer member 13 is provided only on the end closing portion 14b on the outer panel 5 side of each spring portion 12, but is provided on the end closing portion 14b on the mass portion 11 side of each spring portion 12 to provide a mass portion. 11 may be joined.

The mass portion 11, the spring portion 12, and the bonding layer member 13 constituting the sound insulating member 10 are joined and integrated with each other by an adhesive, welding, or the like.
As shown in FIGS. 1 and 2, the sound insulating member 10 is provided at a position away from the reinforcing frame (roof cross member) 8 provided on the outer panel 5 with respect to the outer panel 5 of the vehicle body 1. In this embodiment, the sound insulating member 10 is formed in a band shape between the reinforcing frames 8 adjacent to each other, the longitudinal direction being the direction in which the reinforcing frame 8 extends. Thus, the sound insulation member 10 is formed according to the shape of the outer panel 5 and the arrangement of the reinforcing frame 8 and other members provided on the outer panel 5, and is not limited to a quadrangle, but a triangle, a trapezoid, and other various shapes. Can be formed.

  As shown in FIG. 5, the sound insulating member 10 includes a mass portion 11 and a spring portion 12, thereby constituting a sound insulation structure in which the mass portion 11 is a mass m and the spring portion 12 is a spring having a spring constant k. . In the sound insulation member 10 having such a sound insulation structure, the mass m and the spring constant k are adjusted by adjusting the weight of the mass portion 11 and the pressure of the gas 15 enclosed in the film material 14 constituting the spring portion 12. Adjust.

As described above, the sound insulating member 10 includes the mass portion 11 and the spring portion 12, and the spring portion 12 is formed by enclosing the gas 15 inside the hollow membrane material 14.
Thus, the sound insulation member 10 can constitute a sound insulation structure in which the mass portion 11 is the mass m and the spring portion 12 is the spring having the spring constant k. Further, the spring constant k of the spring portion 12 can be easily adjusted by adjusting the pressure of the gas 15 sealed in the film material 14. Furthermore, since the spring portion 12 has a structure in which the gas 15 is sealed inside the hollow membrane material 14, the amount of the material forming the membrane material 14 is significantly less than that of the urethane layer. Therefore, even if the thickness t2 of the spring portion 12 in the direction in which the mass portion 11 and the outer panel 5 face each other is increased in order to improve sound insulation, an increase in weight and cost of the spring portion 12 can be suppressed. .
Therefore, sound insulation can be improved while suppressing an increase in weight and cost.

Further, the bonding layer member 13 is provided on the side of the spring portion 12 that faces the outer panel 5.
Thereby, the sound insulation member 10 can be joined and attached to the outer panel 5 by the joining layer member 13.
Moreover, high moldability can be obtained by forming the mass portion 11 from polypropylene. Further, by forming the membrane material 14 with an ethylene-vinyl alcohol copolymer, high airtightness can be obtained, and leakage of the gas 15 enclosed in the membrane material 14 can be suppressed. Furthermore, by forming the joining layer member 13 from polyethylene, it can be easily and reliably welded to the outer panel 5.

Further, the specific gravity of the mass portion 11 is made larger than the specific gravity of the film material 14.
Thereby, the function as the mass of the mass part 11 can be exhibited effectively.
Further, the Young's modulus of the film material 14 was made lower than the Young's modulus of the mass portion 11.
Thereby, the spring part 12 becomes easy to elastically deform, and a noise can be suppressed efficiently.

Further, the plurality of spring portions 12 are provided at intervals in the direction along the facing surface.
Thus, when the spring portion 12 is elastically deformed as the mass portion 11 is displaced toward and away from the outer panel 5 side, the adjacent spring portions 12 are prevented from buffering. it can. Thereby, it can suppress that the other spring part 12 inhibits the deformation | transformation of the spring part 12, and can suppress a noise efficiently.

In addition, air is used as the gas 15 enclosed in the film material 14.
Thereby, cost reduction of the sound insulation member 10 can be achieved.
Moreover, if carbon dioxide is used as the gas 15 sealed in the membrane material 14, the speed of sound (the propagation speed of sound waves) is lower than in the air. Thereby, the sound insulation performance can be improved.
Further, if helium is used as the gas 15 sealed in the film material 14, the density becomes lower than that of air. Thereby, the sound insulation performance can be improved.

  Moreover, the sound insulation in the internal space 3 of the vehicle body 1 can be improved by attaching the sound insulation member 10 as described above to the outer panel 5 of the vehicle body 1 of the automobile.

(First modification of embodiment)
In the sound insulating member 10 as described above, as shown in FIGS. 6 and 7, a hard board material 16 can be added to the bonding layer member 13 side. In this case, the board material 16 can be formed of a resin material harder than the film material 14 or the like. Such a board material 16 can be provided so as to be sandwiched between the spring portion 12 and the bonding layer member 13.

(Second modification of the embodiment)
Further, as shown in FIG. 8, for example, the sound insulating member 10 can be mounted not on the outer panel 5 side but on the inner panel 6 side. In this case, the sound insulating member 10 can be provided so that the bonding layer member 13 is bonded to the inner panel 6 and the mass portion 11 is positioned on the outer panel 5 side.

(Third Modification of Embodiment)
Moreover, in the said embodiment, although each spring part 12 was made into circular shape in cross section, it is not restricted to this. For example, as shown in FIGS. 9 and 10, the spring portion 12B may be formed in a substantially rectangular shape having a larger cross-sectional area than the spring portion 12 of the above embodiment. In this case, you may make it make the space | interval of the adjacent spring parts 12B narrower than the space | interval of the spring parts 12 in the said embodiment.

(Fourth modification of the embodiment)
Further, for example, as shown in FIG. 11, the spring portion 12C may have a hexagonal cross section, and the spring portions 12C adjacent to each other may be arranged without a gap to form a so-called honeycomb shape.

The present invention is not limited to the above-described embodiment and its modifications described with reference to the drawings, and various modifications can be considered within the technical scope thereof.
For example, the mass portion 11 and the film material 14 may be integrally formed. Thereby, it is not necessary to join the mass part 11 and the film | membrane material 14 separately, and the sound-insulation member 10 can be manufactured efficiently.
For example, in the said embodiment and its modification, although the sound-insulation member 10 was provided in the roof part of the vehicle body 1, it is not restricted to this. The sound insulation member 10 may be provided in other parts such as a door, a pillar, a bonnet, a trunk, and a body panel of the vehicle body 1. The sound insulation member 10 is not limited to an automobile, and may be provided on other structures such as a building ceiling, a wall, a floor, and covers of various devices.
Manufacturing and handling are facilitated by configuring the sound insulation structure with the sound insulation member 10 independent of the vehicle body 1, but a sound insulation structure including the mass portion 11 and the spring portion 12 may be directly provided on the partition member.
And the structure in the said embodiment is an example of this invention, A various change is possible in the range which does not deviate from the summary of the said invention.

1 Car body (structure)
3 Internal space 4 External 5 Outer panel (partition member)
6 Inner panel (partition member)
DESCRIPTION OF SYMBOLS 10 Sound insulation member 11 Mass part 12, 12B, 12C Spring part 13 Joining layer member 14 Film | membrane material 14a Cylindrical part 14b End part obstruction | occlusion part 15 Gas 16 Board material

Claims (9)

A mass portion that is arranged at an interval with respect to a partition member that partitions the internal space and the outside of the structure, and has a planar shape at least partially;
A plurality of spring portions arranged on the side of the mass portion facing the partition member;
The spring portion is
A hollow membrane material having airtightness and flexibility;
A gas sealed inside the membrane material;
A sound insulation structure characterized by comprising: Constituting a sound insulation member including the mass portion and the spring portion;
The sound insulation member is
The sound insulation structure according to claim 1, further comprising a bonding layer member provided on a side of the spring portion facing the partition member and capable of being bonded to the partition member. The mass portion is made of polypropylene,
The film material is made of an ethylene-vinyl alcohol copolymer,
The sound insulation structure according to claim 2, wherein the bonding layer member is made of polyethylene. The mass portion is formed of a material having a larger specific gravity than the film material of the spring portion.
The sound insulation structure according to any one of claims 1 to 3, wherein the sound insulation structure is provided. The film material of the spring part is formed of a material having a Young's modulus lower than that of the mass part,
The sound insulation structure according to any one of claims 1 to 4, wherein the sound insulation structure is provided. The plurality of spring portions are arranged at intervals from each other in a direction along the facing surface facing the partition member.
The sound insulation structure according to any one of claims 1 to 5, wherein The sound insulation structure according to any one of claims 1 to 6, wherein the gas is air. The sound insulation structure according to any one of claims 1 to 6, wherein the gas is carbon dioxide or helium. 9. The structure according to claim 1, wherein the structural body is a vehicle body of the automobile, and the partition member is an outer panel of the vehicle body or an inner panel that forms an interior of the vehicle body. Sound insulation structure.

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