JP2003118364A - Built-in sound absorbing material for vehicle door - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a built-in sound absorbing material for a vehicle door capable of effectively reducing noise transmitted from the outside of the vehicle to the vehicle inside or transmitted reversely. SOLUTION: This sound absorbing material built in a door structure D of an automobile is formed of a foam body 1 with a specific gravity of about 0.05-0.4 for reducing noise. Alternatively, the sound absorbing material is constructed of a sound absorbing layer formed of the foam 1 with the specific gravity of about 0.05-0.4 and a sound insulating layer 2 formed of a material with a specific gravity of 0.4 or more, or the sound absorbing material having a hollow part 3 arranged in the longitudinal direction and filled with fine particle powder 4 or a fibrous material 5 is used for reducing noise.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound absorbing material incorporated in a vehicle door structure.

[0002]

2. Description of the Related Art Conventionally, in order to prevent noise outside the vehicle from entering the inside of a vehicle, or to prevent the sound inside the vehicle from leaking out of the vehicle, inside a door structure composed of a door panel and a door trim. , Some of which are equipped with a sound absorbing material formed of felt or the like whose main raw material is fibrous glass wool. This suppresses the noise passing through the door panel from being absorbed inside the door structure and reaching the inside of the vehicle.

Similarly, there is a door structure in which a shock absorbing pad formed by providing a solid layer around a foamed resin is provided so as to absorb the collision energy at the time of a side collision of an automobile ( Japanese Utility Model Publication No. 6-78033).

[0004]

However, the sound absorbing material made of felt or the like does not have a sufficient sound absorbing effect, and the noise outside the vehicle still enters the inside of the vehicle. Similarly,
It is also impossible to effectively prevent the sound inside the vehicle from leaking out of the vehicle. Further, the impact absorbing pad composed of the foamed resin and the solid layer can effectively absorb the collision energy, but its material has little effect of suppressing noise.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a sound absorbing material for a vehicle door, which can effectively suppress the noise transmitted from the outside of the vehicle to the inside of the vehicle or vice versa.

[0006]

In order to achieve the above object, the invention according to claim 1 is an automobile door structure (D).
It has a specific gravity of approximately 0.05 to 0.4.
The foam (1) is used to suppress noise. The door structure (D) includes a door panel (P) on the outside of the vehicle and a door trim (T) attached to the inside of the vehicle.
It consists of and.

The invention according to claim 2 is built in a door structure (D) of an automobile and has a specific gravity of approximately 0.
It is characterized in that it comprises a sound absorbing layer made of a foamed body (1) of 05 to 0.4 and a sound insulation layer (2) made of a material having a specific gravity of 0.4 or more to suppress noise.

Further, the invention according to claim 3 is to be built in a door structure (D) of an automobile, and is made of a foam (1), and a hollow portion (3) is provided in the longitudinal direction thereof. The hollow portion (3) is filled with the fine particle powder (4) or the fibrous material (5) to suppress noise.

Further, the invention according to claim 4 is to be built in a door structure (D) of an automobile, and is a sound insulating layer made of a foam (1) and a material having a specific gravity of 0.4 or more. A layer (2) is provided, and a hollow portion (3) is provided in the longitudinal direction thereof, and the hollow portion (3) is filled with fine particle powder (4) or fibrous material (5) to suppress noise. It is characterized by doing.

The invention according to claim 5 is characterized in that the sound absorbing material for a vehicle door built in according to claim 1 or 2 is provided with a hollow portion (3) in the longitudinal direction.

Further, the invention according to claim 6 is the sound absorbing material for a vehicle door according to any one of claims 1 to 5, wherein a plurality of projections (6) or / and a plurality of recesses are provided on the surface in the longitudinal direction. It is characterized by being formed.

Further, in the invention according to claim 7, the sound absorbing material for a vehicle door according to claim 5 is provided with a hollow portion in the longitudinal direction, and at least a part thereof is closed. Characterize.

The symbols in the above parentheses correspond to the symbols described in the drawings and the embodiments of the invention described later.

The sound absorbing material for a vehicle lower portion according to claim 1 of the present invention is built in a door structure of an automobile,
Since it is made of foam having a specific gravity of approximately 0.05 to 0.4, noise that has entered the door structure is absorbed and entry into the vehicle is suppressed. Further, this sound absorbing material has a specific gravity of approximately 0.05 to 0.
Since it is made of the foamed material of No. 4, it has excellent sound absorption, and therefore noise is effectively absorbed.

In the sound absorbing material for a vehicle door according to the second aspect, in addition to the sound absorbing layer, a sound insulating layer made of a material having a specific gravity of 0.4 or more is provided, so that both the sound absorbing function and the sound insulating function are provided. Therefore, noise can be suppressed more effectively.

Further, the vehicle door built-in sound absorbing material according to claim 3 is made of a foam, and a hollow portion is provided in the longitudinal direction thereof, and the hollow portion is provided with fine particle powder or fibrous material. Since it is filled, it is possible to more effectively suppress the intrusion of noise into the vehicle by the foam and the fine particle powder or the fibrous material.

The sound absorbing material for a vehicle door according to a fourth aspect comprises a sound absorbing layer made of foam and a sound insulating layer, a hollow portion is provided in the longitudinal direction thereof, and the hollow portion has fine particles. Since it is filled with powder or fibrous material,
The sound absorbing layer, the sound insulating layer, and the fine particle powder or the fibrous material can more effectively suppress the intrusion of noise.

Further, the sound absorbing material for a vehicle door according to the fifth aspect comprises only the foam or the foam and the sound insulating layer, and the hollow portion is provided in the longitudinal direction thereof. The inner surface is formed to increase the overall surface area. Therefore, the sound absorbing area is expanded and the sound absorbing effect is improved.

Further, in the sound absorbing material for a vehicle door according to the sixth aspect, since the plurality of protrusions and / or the plurality of recesses are formed on the surface in the length direction, the sound absorbing area is widened and the sound absorbing is increased. The effect is improved.

Furthermore, in the sound absorbing material for a vehicle door according to the present invention, since the hollow portion is provided in the longitudinal direction and at least a part thereof is closed, noise is prevented from passing through the hollow portion. Can improve the noise effect.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an external side view of a vehicle to which a vehicle door built-in sound absorbing material according to an embodiment of the present invention is attached, and FIG. 2 is a front view showing a door structure D thereof.

As shown in FIGS. 1 and 2, the vehicle door built-in sound absorbing material according to the embodiment of the present invention is built in a door structure D including a door panel P and a door trim T. Then, three are mounted on the inner surface of the door trim T. The number of sound absorbing materials to be mounted is not limited.

As shown in FIG. 3, this sound absorbing material is made of a solid foam 1 having a specific gravity of approximately 0.05 to 0.4. As for the mounting method, as shown in FIG. 3 (a), it may be mounted via the adhesive material 7 attached to the bottom surface of the foam body 1, or as shown in FIG. 3 (b), the door panel. It may be mounted by fitting the flange 8 formed on the P.

The sound absorbing material is shown in FIGS. 4 (a), (b),
As shown in (c) and (d), the specific gravity is approximately 0.05 to 0.
The sound absorbing layer made of the foam 1 of No. 4 and the sound insulating layer 2 made of a material having a specific gravity of 0.4 or more may be used. Noise can be suppressed in terms of both the sound absorption effect and the sound insulation effect by using the multilayer structure.

Further, this sound absorbing material, as shown in FIG.
As the foam body 1, for example, the foam body 1 having a specific gravity of approximately 0.05 to 0.6 is used, and the hollow portion 3 provided in the longitudinal direction thereof.
In addition, the fine particle powder 4 or the fibrous material 5 may be filled therein. Carbon or the like is suitable as the fine particle powder 4, and glass wool or the like can be used as the fibrous material 5. By filling the fine particle powder 4 and the like, noise can be suppressed more effectively. 5A and 5B, the fine particle powder 4 is shown.
And the fibrous material 5 is filled in (c) and (d).

The present inventor conducted an experiment to compare the sound absorbing effect between the sound absorbing material in which the hollow portion 3 of the foam 1 was filled with the fine particle powder 4 and the sound absorbing material in which the hollow portion 3 was left as it was. In this experiment, as shown in FIG. 12, a hollow portion 3 formed in a foam body 1 (specific gravity: 0.50) having a height of 20 mm was filled with a fine particle powder (for example, carbon black) 4, and another was not. Using a sound pressure generator G provided in the sound source room R to generate noise, and the transmitted sound is measured by the sound pressure measuring device M. It was The measurement conditions of this experiment are as follows. Measurement frequency: 100Hz-10000Hz
(1/3 octave width), Sound source room sound pressure: Reverberation room 90d
B uniform, sound pressure sampling condition: F characteristic (average sound pressure for 30 seconds).

As a result of the experiment, it is confirmed that the sound absorbing material in which the hollow part 3 is filled with the fine particle powder 4 has a sound insulation property improved by 6.3 dB at a value of 1 to 4 kHz as compared with the sound absorbing material having the hollow part 3. Was done. Further, in the frequency band, a difference was particularly observed around 1 to 4 kHz, and an improvement of 10 dB or more was confirmed. This is because when fine particle powder (for example, carbon black) 4 is filled, air between fine particle diameters in carbon repeats expansion and compression, and heat transfer occurs due to this expansion and compression process, resulting in sound energy. It is considered that this is because the sound is lost and sound absorption occurs.

The fine particle powder 4 or the fibrous material 5
As shown in FIGS. 6 (a), (b), (c), and (d), is a hollow portion provided in the longitudinal direction of a sound absorbing layer 2 made of foam 1 and a sound insulating layer 2. 3 can be filled. With this configuration, the foam 1, the sound insulation layer 2, the fine particle powder 4 or the fibrous material 5 can effectively suppress noise.

Further, as shown in FIG. 7, the sound absorbing material may be provided with a hollow portion 3 in its longitudinal direction. In this way, by providing the hollow portion 3, the surface area is expanded as compared with a solid surface area, so that the sound absorbing effect is improved. In particular, since the energy of the sound that has entered the hollow portion 3 is attenuated by the air layer inside, the noise is further suppressed. The shape of the hollow portion 3 is as shown in FIG.
There are various types as shown in (b) and (c), and a plurality of hollow portions 3 may be provided as shown in FIG. 4 (d).

The shape of the foam 1 is as shown in FIG.
As shown in (c), (d), FIG. 9, etc., a plurality of protrusions 6 may be formed on the surface. Instead of this, a plurality of recesses may be formed, or a plurality of protrusions and a plurality of recesses may be combined. In this way, by providing the plurality of protrusions 6, the surface area is expanded as compared with a smooth surface, so that the sound absorbing effect is improved. The protrusions 6 can have various shapes by changing the height and the interval between adjacent protrusions.

Further, the foam 1 is, as shown in FIG.
It may be closed such that at least a part (almost intermediate portion in this example) in the longitudinal direction is narrowed. The narrowing down method can take various forms. FIG. 10 (a) shows the one narrowed down by the string 9,
(B) is the one narrowed down by the binding metal fitting 10 of the binding device (stapling). By thus narrowing down, it is possible to prevent passage of sound and suppress noise more effectively.

As shown in FIG. 11, in the case where the hollow portion 3 is filled with the fine particle powder 4 and the fibrous material 5, the crushed portion 11 is formed by baking the end thereof,
The form may be such that a lid is provided. This makes it possible to prevent the passage of sound more reliably. The crushing method may be performed while maintaining the entire shape as shown in FIG. 11A, or may be performed by narrowing the end portion as shown in FIG.

Although the sound absorbing material is attached to the inner surface of the door trim T in the embodiment of the present invention, the same sound absorbing effect can be obtained even if the sound absorbing material is attached to the inner surface of the door panel P.

[0034]

As described above, the sound absorbing material for the vehicle lower portion according to claim 1 of the present invention is built in the door structure of an automobile and has a specific gravity of about 0.05 to 0.4. Since it is made of foam, noise that has entered the door structure is absorbed, and entry into the vehicle is suppressed.

In the sound absorbing material for a vehicle door according to the second aspect, in addition to the sound absorbing layer, a sound insulating layer made of a material having a specific gravity of 0.4 or more is provided, so that noise can be suppressed more effectively. be able to.

Furthermore, the sound absorbing material for a vehicle door according to the third aspect is made of a foam, and a hollow portion is provided in the longitudinal direction thereof, and the hollow portion is made of fine particle powder or fibrous material. Since it is filled, it is possible to more effectively suppress the intrusion of noise into the vehicle by the foam and the fine particle powder or the fibrous material.

The sound absorbing material for a vehicle door according to a fourth aspect comprises a sound absorbing layer made of foam and a sound insulating layer, a hollow portion is provided in the longitudinal direction thereof, and the hollow portion has fine particles. Since it is filled with powder or fibrous material,
Noise is further effectively suppressed by the sound absorbing layer, the sound insulating layer, and the fine particle powder or the fibrous material.

Furthermore, the vehicle door built-in sound absorbing material according to the present invention has only a foamed body or a foamed body and a sound insulating layer, and a hollow portion is provided in the longitudinal direction thereof, so that the sound absorbing effect is improved. The noise can be further suppressed.

Further, in the sound absorbing material for a vehicle door according to the sixth aspect, since the plurality of protrusions and / or the plurality of recesses are formed on the surface in the longitudinal direction, the sound absorbing effect is similarly improved and the noise is reduced. Can be further suppressed.

Further, in the sound absorbing material for a vehicle door according to the seventh aspect, since the hollow portion is provided in the longitudinal direction and at least a part thereof is closed, noise is prevented from passing through the hollow portion. It is possible to improve the noise suppression effect.

[Brief description of drawings]

FIG. 1 is an external side view showing an automobile to which a vehicle door built-in sound absorbing material according to an embodiment of the present invention is attached.

FIG. 2 is a front view showing the door structure of the automobile in FIG.

FIG. 3 is a perspective view showing a sound absorbing material for a vehicle door according to the embodiment of the present invention.

FIG. 4 is a cross-sectional view showing another shape of the sound absorbing material for vehicle door interior according to the embodiment of the present invention.

FIG. 5 is a cross-sectional view showing another shape of the sound absorbing material for vehicle door interior according to the embodiment of the present invention.

FIG. 6 is a cross-sectional view showing another shape of the sound absorbing material for the vehicle door interior according to the embodiment of the present invention.

FIG. 7 is a cross-sectional view showing another shape of the sound absorbing material for vehicle door interior according to the embodiment of the present invention.

FIG. 8 is a cross-sectional view showing another shape of the sound absorbing material for vehicle door interior according to the embodiment of the present invention.

FIG. 9 is a perspective view showing another shape of the sound absorbing material for the vehicle door interior according to the embodiment of the present invention.

FIG. 10 is a perspective view showing another shape of the sound absorbing material for the vehicle door interior according to the embodiment of the present invention.

FIG. 11 is a perspective view showing another shape of the sound absorbing material for the vehicle door interior according to the embodiment of the present invention.

FIG. 12 is an explanatory diagram showing a performance experiment of the sound absorbing material for the vehicle door interior according to the embodiment of the present invention.

[Explanation of symbols]

1 foam 2 sound insulation layer 3 Hollow part 4 Fine particle powder 5 fibrous materials 6 protrusion 7 Adhesive 8 flange 9 strings 10 binding hardware 11 crushed part D door structure G sound pressure generator M sound pressure measuring instrument P door panel R sound source room T door trim

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shuji Kurusu             2-8 Mitsunomachi, Nishi-ku, Hiroshima-shi, Hiroshima             Nishikawa Rubber Industry Co., Ltd. (72) Inventor Yoshihiro Ikuma             2-8 Mitsunomachi, Nishi-ku, Hiroshima-shi, Hiroshima             Nishikawa Rubber Industry Co., Ltd. (72) Inventor Shinichiro Emori             2-8 Mitsunomachi, Nishi-ku, Hiroshima-shi, Hiroshima             Nishikawa Rubber Industry Co., Ltd. F term (reference) 3D023 BA03 BB22 BC01 BD03 BE02                       BE03 BE04 BE06

Claims (7)

[Claims] 1. A sound absorbing material for a vehicle door built-in, which is built in a door structure of an automobile and is made of a foam having a specific gravity of about 0.05 to 0.4 to suppress noise. 2. A sound absorbing layer, which is built in a door structure of an automobile and is made of foam having a specific gravity of about 0.05 to 0.4, and a sound insulating layer made of a material having a specific gravity of 0.4 or more. Sound absorbing material for built-in vehicle doors, which is characterized by suppressing noise. 3. An automobile door structure, which is made of foam and has a hollow portion in a longitudinal direction thereof, and the hollow portion is filled with a fine particle powder or a fibrous material. A sound-absorbing material for vehicle doors, which suppresses noise. 4. An automobile door structure, comprising a sound absorbing layer made of foam and a sound insulating layer made of a material having a specific gravity of 0.4 or more, and a hollow portion provided in the longitudinal direction thereof. A noise absorbing material for a vehicle door, wherein the hollow portion is filled with fine particle powder or a fibrous material to suppress noise. 5. The sound absorbing material for built-in vehicle door according to claim 1, wherein the sound absorbing material for built-in vehicle door is provided with a hollow portion in a longitudinal direction. 6. The sound absorbing material for a vehicle door built-in has a plurality of protrusions and / or a plurality of recesses formed on a surface thereof in a lengthwise direction. Sound absorbing material for vehicle doors as described in No. 3. 7. The sound-absorbing material for built-in vehicle doors according to claim 5, wherein the sound-absorbing material for built-in vehicle doors is provided with a hollow portion in the longitudinal direction, and at least a part thereof is closed.