JP7180487B2 - Sound absorbing and insulating structure for vehicle and method for manufacturing sound absorbing and insulating structure for vehicle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a sound absorbing and insulating structure using a sound absorbing and insulating material fixed to a body panel of a vehicle, and a method for manufacturing the sound absorbing and insulating structure of the vehicle.

Japanese Patent Laid-Open No. 2002-100000 describes a technique related to a conventional sound absorbing and insulating structure. The sound absorbing and insulating structure of Patent Document 1 uses a sound absorbing and insulating material 100 that utilizes the principle of Helmholtz resonance. As shown in FIG. 6, the sound absorbing and insulating material 100 is composed of two surface members 131 and 132 and a hollow structure portion 102. The hollow structure portion 102 and the surface member 131 are provided with small holes 120 and 130, respectively. ing. When such a sound absorbing and insulating material is used in a vehicle, for example, it is generally fixed to a body panel or the like of the vehicle with a clip or the like (not shown).

JP 2017-151256 A

In a sound absorbing and insulating structure in which a sound absorbing and insulating material is fixed to a vehicle body panel or the like with a connecting member such as a clip, it is necessary to fix a bracket having a clip hole to the body panel or the like, which incurs costs. Further, in the sound absorbing and insulating structure in which the sound absorbing and insulating material is fixed with such a connecting member, additional measures are required to suppress the generation of noise due to vibration or the like.

The present invention has been made to solve the above problems, and the problem to be solved by the present invention is to reduce the cost for fixing the sound absorbing and insulating material and to eliminate the need for noise countermeasures. It is to provide structure.

The above problems are achieved by the inventions of the respective claims. A first invention is a sound absorbing and insulating structure for a vehicle that absorbs and isolates sounds generated inside and outside the vehicle by using a sound absorbing and insulating material having at least one hole and an internal space that communicates with the outside through the hole. The sound absorbing and insulating material covers the body panel of the vehicle and is fixed to the body panel with a thermosetting adhesive. A surface of the sound absorbing and insulating material that is adhered to the body panel is formed in a shape that conforms to the shape of the body panel. Also, the sound absorbing and insulating material is formed of a pulp mold made of cellulose fibers. Further, the sound absorbing and insulating material has a large number of projections, and the height of the large number of projections is increased at positions corresponding to the recesses of the body panel. It is formed so as to match the unevenness of the body panel so that the height dimension is reduced by .

According to the invention, the sound absorbing material is secured to the body panel by a thermosetting adhesive. Therefore, there is no need to provide a connecting structure for fixing the sound absorbing and insulating material, the cost for fixing the sound absorbing and insulating material is reduced, and noise countermeasures for the connecting structure are not required.

According to the second invention, the thermosetting adhesive is a coating type damping material. Therefore, the generation of vehicle noise can be further suppressed by the damping performance of the coating-type damping material.

According to the third aspect of the invention, the surface of the sound absorbing and insulating material that is adhered to the body panel is formed in a shape that conforms to the shape of the body panel. Therefore, even if the body panel has unevenness, it is easy to fix the sound absorbing and insulating material to the body panel.

According to the fourth invention, the sound absorbing and insulating material is made of a pulp mold made of cellulosic fibers. Therefore, it is possible to provide an inexpensive and lightweight sound absorbing and insulating material.

According to a fifth aspect of the present invention, the sound absorbing and insulating material includes a bottom plate portion and a large number of hollow projections protruding from the bottom plate portion, and the bottom plate portion is bonded to the body panel. Also, the protruding end faces of the plurality of protrusions are on the same plane. Therefore, a flat floor surface or the like can be formed by utilizing the projecting end surfaces of a large number of projections.

A sixth aspect of the present invention is a sound absorbing and insulating structure for a vehicle that absorbs and isolates sounds generated inside and outside the vehicle by using a sound absorbing and insulating material having at least one hole and having an internal space communicating with the outside through the hole. A manufacturing method comprising: applying a thermosetting coating-type damping material to a body panel; pressing the sound absorbing and insulating material against the body panel coated with the coating-type damping material; A step of covering with a sound absorbing and insulating material, and a step of thermally curing the coating type damping material. The sound absorbing and insulating material has a large number of protrusions, and the large number of protrusions have a height dimension corresponding to the recesses of the body panel and a height dimension corresponding to the protrusions of the body panel. It is formed according to the unevenness of the body panel so that the height dimension becomes small.

According to this manufacturing method, the coated vibration damping material is applied to the body panel, the sound absorbing and insulating material is pressed against the body panel coated with the coated vibration damping material, and the coated vibration damping material is thermally cured to provide sound absorption and insulation. Since the structure can be formed, the working time can be shortened.

According to the seventh invention, the step of thermally curing the coating type damping material is a baking coating step. Therefore, the sound absorbing and insulating material can be fixed to the body panel without newly adding a process for thermally curing the coating type damping material.

According to the present invention, it is possible to reduce the cost for fixing the sound absorbing and insulating material, and eliminate the need for noise countermeasures.

1 is a schematic side view of a vehicle provided with a sound absorbing and insulating structure according to Embodiment 1 of the present invention; FIG. FIG. 4 is a vertical cross-sectional view showing a state in which the sound absorbing and insulating material is fixed to a floor panel of a vehicle body; 4 is an enlarged perspective view of the sound absorbing and insulating material; FIG. FIG. 10 is a vertical cross-sectional view showing a modification of the state in which the sound absorbing and insulating material is fixed to the floor panel of the vehicle body; FIG. 4 is a vertical cross-sectional view showing a state in which the sound absorbing and insulating material is fixed to the dash panel of the vehicle body; FIG. 11 is a perspective view showing a conventional sound absorbing and insulating material;

[Embodiment 1]
A sound absorbing and insulating structure for a vehicle according to Embodiment 1 of the present invention will be described below with reference to FIGS. 1 to 5. FIG. The vehicle sound absorbing and insulating structure according to the present embodiment is a structure used in the floor of a vehicle body. Here, front, rear, left, right, and up and down shown in the drawing correspond to front, rear, left, right, and up and down of the vehicle having the sound absorbing and insulating structure.

<Overview of sound absorption and insulation structure>
As shown in FIG. 1, the sound absorbing and insulating structure for a vehicle according to the present embodiment includes a sound absorbing and insulating material 2 installed on a floor panel 4 of a vehicle body, and a coating type in which the sound absorbing and insulating material 2 is fixed to the floor panel 4. A damping material 1 and a floor sheet 3 covering the upper surface of the sound absorbing and insulating material 2 are provided.

<About the sound absorbing and insulating material 2>
As shown in FIG. 2, the sound absorbing and insulating material 2 has a different thickness according to the unevenness of the floor panel 4 so as to absorb the unevenness of the floor panel 4 . That is, the upper surface of the sound absorbing and insulating material 2 can horizontally support the floor sheet 3 while the sound absorbing and insulating material 2 covers the uneven floor panel 4 . As shown in FIGS. 2 and 3, the sound absorbing and insulating material 2 has a large number of truncated quadrangular pyramid-shaped protrusions 20 protruding upward. That is, the convex portion 20 includes an upper end wall portion 21 and inclined side wall portions 22 on the front, rear, left, and right sides, and an internal space S is formed inside. Further, the height dimension of the projection 20 is set so as to increase at the position of the recess of the floor panel 4 and to decrease at the position of the projection of the floor panel 4 . The lower ends of the projections 20 are connected to each other by a bottom plate portion 23 along the unevenness of the floor panel 4, and are arranged at equal intervals in the vehicle front-rear direction and vehicle width direction. Therefore, recesses are formed between the respective protrusions 20 . Further, the upper end wall portion 21 of each projection 20 is held on the same plane, and the upper end wall portion 21 of each projection 20 is covered with the floor sheet 3 . That is, the upper end wall portion 21 of the convex portion 20 corresponds to the projecting end surface of the convex portion of the present invention.

Each convex portion 20 has a hole 21h that opens upward in the upper end wall portion 21, and a hole 22h that opens obliquely upward in the inclined side wall portion 22 on the rear side. As a result, the internal space S of the convex portion 20 and the outside of the convex portion 20 communicate with each other through the holes 21h and 22h.

As a material for the sound absorbing and insulating material 2, a material suitable for sound absorption and sound insulation can be used, and it is preferable to use a material having rigidity capable of maintaining the outer shape of the projections 20 and the recesses. For example, suitable materials for the sound absorbing and insulating material 2 include fiber laminates of cellulosic fibers, animal fibers, mineral fibers, inorganic fibers, and the like. Among them, a fiber laminate of cellulosic fibers is preferable as a material for the sound absorbing and insulating material 2 because it has excellent sound absorbing performance and sound insulating performance and is lighter than metal or resin. Therefore, in this embodiment, cellulose-based fibers are used as the material for the sound absorbing and insulating material 2 .

<Regarding the coating type damping material 1>
The coating-type damping material 1 used in this embodiment is a thermosetting coating-type damping material, and is a liquid paint having a certain viscosity and stickiness before being thermally cured. As such a coating-type damping material 1, for example, a water-based coating-type damping material disclosed in Japanese Unexamined Patent Application Publication No. 2010-111746 can be used. Specifically, the coating-type damping material 1 can be produced from a resin emulsion, an additive (water retaining material), an inorganic filler, microballoon particles, and the like. More specifically, for example, a styrene emulsion is used as the resin emulsion, calcium carbonate and mica (mica) are used as the inorganic filler, propylene glycol is used as the water retention agent, and microballoon particles are blended as the foaming agent for the damping material. The coating type damping material 1 can be manufactured by The coating-type damping material 1 can be applied directly to the floor panel 4, or can be applied over the sealer (not shown) after placing it on the upper surface of the floor panel 4. FIG. This coating type damping material 1 can be cured by heating at a temperature of 70° C. to 200° C. for 5 to 30 minutes in the baking coating process, and can be cured in the baking coating process.

<How to fix the sound absorbing and insulating material 2 to the floor panel 4>
First, the coating-type damping material 1 is applied to a predetermined position of the floor panel 4 of the vehicle body by a robot or the like. A predetermined position of the floor panel 4 coated with the coating type damping material 1 is covered with the sound absorbing and insulating material 2 and pressed. Specifically, as shown in FIG. 2 and the like, a bottom plate portion 23 that connects each projection 20 of the sound absorbing and insulating material 2 is crimped to a predetermined position of the floor panel 4 . At this time, the bottom plate portion 23 is held by the floor panel 4 along the unevenness of the floor panel 4 . Next, by applying heat to the coating type damping material 1 in the baking coating process, the coating type damping material 1 is thermally cured, and the sound absorbing and insulating material 2 is fixed to the floor panel 4 . As a result, the bottom of the internal space S of the convex portion 20 constituting the sound absorbing and insulating material 2 is closed by the floor panel 4 of the vehicle body, and the sound absorbing and insulating material 2 is generated inside and outside the vehicle using the principle of Helmholtz resonance. It can absorb and insulate sound.

<Advantages of the sound absorbing and insulating material 2 according to the present embodiment>
A sound absorbing and insulating material 2 according to the present embodiment is fixed to a floor panel 4 of a vehicle body with a thermosetting coated damping material 1 . Therefore, there is no need to provide a connecting structure for fixing the sound absorbing and insulating material 2, the cost for fixing the sound absorbing and insulating material 2 is reduced, and noise countermeasures for the connecting structure are not required. Furthermore, the damping performance of the coating type damping material 1 can further suppress the generation of vehicle noise.

[Change example]
The present invention is not limited to the above embodiments, and modifications can be made without departing from the scope of the present invention. For example, in Embodiment 1, the sound absorbing and insulating material 2 is fixed to the floor panel 4 with the upper end wall portion 21 of the projection 20 of the sound absorbing and insulating material 2 in contact with the floor sheet 3 (FIG. 2). ). However, as shown in FIG. 4, the sound absorbing and insulating material 2 may be fixed with the upper end wall portion 21 and the floor sheet 3 separated from each other. Furthermore, in Embodiment 1, an example in which the sound absorbing and insulating material 2 is fixed to the floor panel 4 provided in a substantially horizontal direction is shown (FIG. 2). However, the coating type damping material 1 can be coated not only on the horizontal surface but also on the vertical surface, for example. Therefore, the sound absorbing and insulating material 2 can be fixed to the dash panel 5 arranged substantially vertically as shown in FIG. In the first embodiment, the sound absorbing and insulating material 2 is composed of the truncated quadrangular pyramid-shaped projections 20, and the holes 21h and 22h are provided in the projections 20. The size, number, etc. can be appropriately changed according to the application.

1: Coating type damping material (adhesive)
2...Sound absorbing and insulating material 4...Floor panel (body panel)
20... Convex portion 21... Upper end wall portion (protruding end face)
21h... Hole 22h... Hole 23... Bottom plate portion S... Internal space

Claims (5)

A sound absorbing and insulating structure for a vehicle that absorbs and isolates sounds generated inside and outside the vehicle using a sound absorbing and insulating material having at least one hole and having an internal space that communicates with the outside through the hole,
The sound absorbing and insulating material covers the body panel of the vehicle and is fixed to the body panel with a thermosetting adhesive,
A surface of the sound absorbing and insulating material that is adhered to the body panel is formed in a shape that conforms to the shape of the body panel,
The sound absorbing and insulating material is formed of a pulp mold made of cellulose fiber,
The sound absorbing and insulating material has a large number of protrusions, and the large number of protrusions have a height dimension corresponding to the recesses of the body panel and a height dimension corresponding to the protrusions of the body panel. A sound absorbing and insulating structure that is formed in accordance with the unevenness of the body panel so that the height dimension is reduced . A sound absorbing and insulating structure for a vehicle according to claim 1,
A sound absorbing and insulating structure, wherein the thermosetting adhesive is a coating-type damping material. A sound absorbing and insulating structure for a vehicle according to any one of claims 1 and 2 ,
The sound absorbing and insulating material includes a bottom plate portion and the plurality of hollow convex portions protruding from the bottom plate portion,
A sound absorbing and insulating structure in which the bottom plate portion is adhered to the body panel, and projecting end faces of the plurality of projections are coplanar. A method for manufacturing a sound absorbing and insulating structure for a vehicle that absorbs and isolates sounds generated inside and outside the vehicle by using a sound absorbing and insulating material having at least one hole and having an internal space that communicates with the outside through the hole,
a step of applying a thermosetting coating-type damping material to the body panel;
a step of pressing the sound absorbing and insulating material against the body panel coated with the coating type damping material to cover the body panel with the sound absorbing and insulating material;
a step of thermally curing the coating-type damping material;
with
The sound absorbing and insulating material has a large number of protrusions, and the large number of protrusions have a height dimension corresponding to the recesses of the body panel and a height dimension corresponding to the protrusions of the body panel. A manufacturing method in which the body panel is formed according to the unevenness of the body panel so that the height dimension is reduced . A method for manufacturing a sound absorbing and insulating structure for a vehicle according to claim 4 ,
The manufacturing method, wherein the step of thermally curing the coating type damping material is a baking coating step.

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