KR20150122567A - Dash pad for vehicle - Google Patents

Abstract

The present invention relates to a dash pad for a vehicle and, more specifically, provides a low weight sound-absorbing type dash pad for a vehicle, which can maximize sound-insulating performance and promote weight reduction, production cost reduction, reduction of processes, and in-line workability improvement. To this end, disclosed is the low weight sound-absorbing type dash pad for a vehicle, which is formed by mutually bonding a first sound-absorbing layer made of a superfine fiber, a sound-insulating layer made of a thermoplastic resin, and a second sound-absorbing layer made of a thermoplastic fiber or a thermoplastic multi-lobal fiber.

Description

[0001] The present invention relates to a dash pad for vehicle,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a low-weight sound-absorbing dash pad for an automobile, and more particularly, to a low-weight sound-absorbing dash pad formed by bonding a sound-

In general, a dash panel is mounted at a boundary between an engine room and a vehicle interior, and a dash pad, which is a kind of sound absorbing material that absorbs or blocks engine noise or the like from being transmitted to a vehicle interior, is mounted on the dash panel Respectively.

The dash pad functions to block, dampen and absorb noise of the engine and to prevent the combined energy of low frequency and high frequency generated during traveling from being transmitted to the interior space of the vehicle.

In the case of a conventional dash pad for a vehicle, as shown in Table 1 below, different materials are stacked in different thicknesses and weights depending on the type of vehicle.

As shown in FIG. 1, the dash pads shown in Table 1 are stacked in a two-layer to four-layer structure from the sound-absorbing layer (engine room side) toward the sound-insulating layer (indoor side).

In order to improve the sound absorption performance, the conventional dash pads are manufactured by stacking two or more layers of different materials for each vehicle type. However, PU (polyurethane) base material is applied to the sound-absorbing layer and Hard Since PET (Polyethyleneterephthalate) is applied, there is a problem that weight and cost increase to improve absorption sound performance by vehicle type.

In addition, since molding, trimming mold and PU foaming mold are required for production of actual products including starting molds and mass production molds for confirming performance verification at the time of mass production, there is a problem that the investment cost and manufacturing cost increase, and the sound- (PA6) for the purpose of increasing the cost and increasing the number of steps.

Accordingly, it is an object of the present invention to provide a low-weight, sound-absorbing type dash pad for an automobile which can maximize the sound absorption performance and improve the indoor quietness of a vehicle.

It is another object of the present invention to provide a lightweight, low noise absorbing dash pad for an automobile which can reduce weight, improve fuel economy of a vehicle, reduce cost, and improve processability and inline workability.

According to an aspect of the present invention, there is provided a sound absorbing structure comprising a first sound absorbing layer made of microfibers, a sound insulating layer made of a thermoplastic resin, a thermoplastic fiber or a thermoplastic multi-lobal fiber, And a second sound-absorbing layer formed of a first sound-absorbing layer and a second sound-absorbing layer.

Preferably, the microfibers are obtained by blending meltblown polypropylene fibers with 100 to 1,000 g / m < 2 > of polypropylene staple fibers.

The sound insulating layer may be composed of one or two of olefin-based resin and olefin-based elastomer, and has a unit weight of 100 to 5,000 g / m 2.

The second sound-absorbing layer may be a polyethylene terephthalate (PET) nonwoven fabric containing 10% to 50% by weight of low melting (LM) fibers, and the low melting point fibers may be polyethylene / Polyethylene terephthalate composite fibers, polyethylene / polypropylene composite fibers, or polypropylene / polyethylene terephthalate composite fibers, and the unit weight is 100 to 2,000 g / m 2.

Further, the first sound-absorbing layer is disposed on the dash panel of the vehicle such that the first sound-absorbing layer is disposed on the side of the engine room where the noise is received.

Through the above-mentioned means for solving the problems, the present invention provides the following effects.

First, by applying micro-fibers, which are only 100-1,000 g per unit area (m 3), to the sound-absorbing layer and bonding them to the sound-insulating layer, it is possible to maximize the sound-absorbing performance by using excellent sound-

Second, the use of microfibers instead of the polyurethane used as a sound-absorbing layer can eliminate the use of polyurethane foam molds, thereby improving productivity and reducing costs.

Third, PA6 film and adhering process for laminating a sound-absorbing layer and a sound-insulating layer are not needed, thus cost reduction and process water reduction can be realized.

1A to 1D are diagrams showing the construction of a conventional dash pad.
2 is a configuration diagram of a light-weight sound-absorbing type dash pad for an automobile according to the present invention.
3 is a graph showing a result of sound absorption test of a light-weight sound-absorbing type dash pad for a vehicle according to the present invention.
4 is a graph showing the results of sound insulation tests of a light-weight sound-absorbing type dash pad for a vehicle according to the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains.

Referring to FIG. 2, the present invention provides a dash pad, which is a kind of sound absorbing material that is attached to a dash panel for a vehicle and absorbs or blocks engine noises or the like from being transmitted to a vehicle interior. The dash pad includes a first sound- A sound-absorbing layer made of a thermoplastic resin, and a second sound-absorbing layer made of a thermoplastic fiber or a thermoplastic multi-lobal fiber.

Here, the microfiber used in the first sound-absorbing layer may be formed by blending polypropylene staple fiber at 100 to 1,000 g / m 2 with meltblown polypropylene fiber.

More specifically, when meltblown polypropylene fibers are spun down from the upper side in a die on which meltblown polypropylene fibers are wound, air pulsing is performed on one side, Polypropylene staple fibers are spun onto the meltblown polypropylene fibers at the other side while being oriented toward the polypropylene fibers to produce microfine yarns of 100 to 1,000 g / m 2 in which the polypropylene staple fibers are joined to the meltblown polypropylene fibers .

Further, a sound-insulating layer is interposed between the first sound-absorbing layer and the second sound-absorbing layer, wherein the sound-insulating layer is made of a thermoplastic resin and the second sound-absorbing layer is made of a thermoplastic fiber or a thermoplastic modified cross-section yarn.

The sound insulating layer plays a role of sound insulation and also acts to bond the first sound absorbing layer and the second sound absorbing layer.

In a preferred embodiment of the present invention, the sound insulating layer may be composed of one or two of an olefin based resin, which is a thermoplastic resin, and a thermoplastic olefin (TPO), which is a thermoplastic elastomer (TPE) The weight may be from 100 to 5,000 g / m 2.

Further, the second sound-absorbing layer may be made of polyethylene terephthalate (PET), more preferably thermoplastic fiber of hard PET, or thermoplastic modified cross-section yarn, and more specifically 10 wt% to 50 wt% , And Low Melting) fibers. The nonwoven fabric may be a polyethylene terephthalate (PET).

The low melting point fiber may be composed of a polyethylene / polyethylene terephthalate conjugate fiber, a polyethylene / polypropylene conjugate fiber, or a polypropylene / polyethylene terephthalate conjugate fiber, and the unit weight is 100 to 2,000 g / M < 2 >.

When the dash panel of the present invention is applied to a dash panel of a vehicle, the first sound-absorbing layer is disposed on the side of the engine room which is the noise side of the dash panel and the second sound- .

EXAMPLES Hereinafter, examples of the present invention will be described in detail with comparative examples, but the present invention is not limited by the following examples.

Example

A dash pad having a size of 840 mm x 840 mm in which microfibers of D3 as a first sound-absorbing layer, a thermoplastic elastomer (TPE) as a sound-insulating layer, and polyethylene terephthalate (PET) as a second sound-

D3 represents a grade of microfine yarn, D1 represents 180 g per unit area (m2), D2 represents 230 g per unit area (m 2), and D3 represents 330 g per unit area (m 2), respectively.

That is, in the examples, microbubbles of polypropylene staple fibers having a meltblown polypropylene fiber of 330 g / m 2 were used.

In addition, 'D3 (top)' of the dash pad according to the embodiment of Table 2 below means that the microfibers D3 are arranged in the noise side (which is the engine room side of the vehicle).

Comparative Example  1-2

As Comparative Examples 1 and 2, a dash pad having a size of 840 mm x 840 mm in which polyethylene terephthalate (PET), thermoplastic elastomer (TPE) and polyurethane (PU)

For reference, 'PU (phase)' in Table 2 means that the polyurethane (PU) is placed on the side where noise is coming in, and 'PU (lower)' means that the polyurethane (PU) Quot;

Comparative Example  3

As in the above embodiment, a dash pad having a size of 840 mm x 840 mm (thickness: 840 mm x 840 mm) in which a microfiber D3 as a first sound-absorbing layer, a thermoplastic elastomer (TPE) as a sound-insulating layer and a polyethylene terephthalate But the microfiber (D3) was made to be inverted so as to be disposed on the opposite side from the noise side.

For reference, 'D3 (lower)' described in Comparative Example 3 in Table 2 means that the microfiber (D3) is disposed on the opposite side of the noise side (which is the indoor side in the vehicle).

Comparative Example  4 to 5

As Comparative examples 4 to 5, a dash having a size of 840 mm x 840 mm (thickness: 840 mm x 840 mm) in which microfibers of D3 as a sound-absorbing layer and polyethylene terephthalate (PET), thermoplastic elastomer Pad.

For reference, 'D3 (phase)' described in Comparative Example 4 in Table 2 indicates that the microfiber (D3) is disposed on the side where noise is introduced, and 'D3 (lower)' described in Comparative Example 5 indicates that the microfiber And is disposed on the opposite side.

Test Example  One

In order to investigate the sound absorption performance of the dash pad according to the above-described embodiment and comparative example, the sound absorption rate of the dash pad of the embodiment and the comparative example was tested using a conventional simple reverberation method (Alpha Cabin Measurement) Are as shown in Table 3 and FIG. 3 below.

As can be seen from the above Table 3 and FIG. 3, the dash pad according to the embodiment of the present invention, that is, the dash pad in which PET + TPE + D3 And it was found.

Test Example  2

In order to examine the sound insulation performance of the dash pad according to the embodiment and the comparative example, the sound transmission loss ratio was tested using a conventional small cabin method (APA MAT TEST: STL (Sound trans loss)), As shown in Table 4 and Fig.

As shown in Table 4 and FIG. 4, the sound transmission loss ratios of the dash pads according to the embodiment of the present invention, that is, dash pads in which PET + TPE + D3 It can be seen that there is a deviation according to the frequency interval, but it is maintained at the same level with the comparative examples.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the present invention is not limited to the disclosed exemplary embodiments. Forms are also included within the scope of the present invention.

Claims (5)

Characterized in that a first sound-absorbing layer made of microfine fibers, a sound-insulating layer made of thermoplastic resin, and a second sound-absorbing layer made of a thermoplastic fiber or a thermoplastic multi-lobal fiber are bonded to each other Dust absorbing dash pad for low weight.
The method according to claim 1,
Wherein the microfiber is made by blending meltblown polypropylene fibers with polypropylene staple fibers at 100 to 1,000 g / m < 2 >.
The method according to claim 1,
Wherein the sound insulating layer is composed of one or two of an olefin based resin and an olefin based elastomer, and the unit weight is 100 to 5,000 g / m < 2 >.
The method according to claim 1,
The second sound-absorbing layer is a polyethylene terephthalate (PET) nonwoven fabric containing 10 wt% to 50 wt% of low melting (LM) fibers,
The low-melting-
A polyethylene / polyethylene terephthalate conjugate fiber, a polyethylene / polypropylene conjugate fiber, or a polypropylene / polyethylene terephthalate conjugate fiber, and the unit weight is 100 to 2,000 g / m 2. Dust absorbing dash pad for low weight.
The method according to claim 1,
And the first sound-absorbing layer is disposed on the dash panel of the vehicle so that the first sound-absorbing layer is disposed on the side of the engine room where the noise is received.

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