JPS6118538A - Insulator dash for car - Google Patents

Abstract

PURPOSE:To aim at reduction of both noises and vibrations by letting an insulator dash have a structure of 4 layers consisting of a skin layer capable of insulating sound, a sound absorbing layer, a binding layer and finally a viscous foaming material layer, thereby making it sure to hold down both noises and vibrations coming over from an engine room. CONSTITUTION:An insulator dash (5) is set up additionally along the interior side of a car room on a dash panel (1). The insulator dash (5) consists of a sound absorbing layer (6), a skin layer (7) capable of insulating sound, a viscous foaming material layer (8) which is laminated at the side of the dash panel (1) on the sound absorbing layer (6), and finally a binding layer (9) which is placed between the viscous foaming material layer (8) and the sound absorbing layer (6). With such a structure as stated above, both noises and vibrations of medium or low range which come over from an engine room E, can be not only absorbed but controlled or held down by the layer (8) and further, noises of medium or higher range can be surely absorbed by the sound absorbing layer (6), thus enabling the room inside of a car (R) to be quiet.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to an insulator dash for an automobile that is attached to a dash panel surface in a vehicle interior.

(Prior Art and its Problems) An insulator dash is attached to the dash panel surface in front of the front seat in order to prevent engine noise and vibration from the engine compartment from being transmitted into the interior of the vehicle. This insulator dash is generally used in which a sound-insulating skin layer made of rubber, soft vinyl chloride resin, etc. is laminated on a sound-absorbing layer made of felt, polyurethane foam, etc.

However, although this configuration is effective for sound insulation at the mid- and high-frequency range level, it is not sufficient for sound insulation at the mid- and low-frequency range levels. It is necessary to increase the thickness of the skin layer, which leads to a reduction in space within the dormitory, and it is difficult to improve sound absorption and sound insulation properties in a space with limited installation space. In addition, an increase in weight due to an increase in the thickness of the sound-absorbing TAG skin layer or an increase in surface density causes an increase in the weight of the vehicle body and a decrease in the ease of assembly to the vehicle body.

Therefore, recently, a viscous foam layer is installed on the back side of the sound absorbing layer.
Efforts are being made to reduce mid- and low-frequency noise and vibration to make vehicle interiors quieter.

These viscous foam material layers are usually made by impregnating polyurethane foam with a viscous material such as asphalt. The purpose is to attenuate energy by the flow of V, thereby improving sound insulation and vibration damping effects.

However, since the above viscous foam layer is in direct contact with the sound absorbing layer, the flow of the viscous material in the viscous foam layer is directly transmitted to the sound absorbing layer and the sound insulating skin layer 1, resulting in sufficient sound insulation and vibration damping performance. Not done.

Therefore, although the amount and man-hours increased by laminating viscous foam layers, there was a drawback that the desired sound insulation and vibration damping effects could not be obtained.

(Object of the Invention) In view of the above-mentioned circumstances, the present invention has been made in order to make the viscous foam material layer function effectively.The purpose of the present invention is to reliably suppress noise and vibration from the engine compartment, The purpose of this invention is to provide an insulator dash for an automobile that contributes to making the interior of a vehicle quieter by reducing noise and vibration.

(Configuration and Effects of the Invention) In order to achieve the above object, an insulator dash according to the present invention is an insulator dash attached to the indoor side of a dash panel, and includes a sound absorption layer and a layer laminated on the upper surface of the sound absorption layer. and a viscous foam layer laminated on the dash panel side of the sound absorbing layer, and a constraining layer is provided between the sound absorbing layer and the viscous foam layer.

In other words, in order to make the viscous foam layer work effectively, the present invention focuses on the presence of the constraint layer, and makes the insulator dash a four-layer structure consisting of a sound-insulating skin layer, a sound-absorbing layer, a constraint layer, and a viscous foam layer. By firmly sandwiching the viscous foam material layer between the dash panel and the restraint layer in a sandwich-like manner, this viscous foam material layer can work reliably, reducing the magnitude of mid- and low-range noise and vibration transmitted from the engine room. To ensure that noise and vibration reductions are achieved by absorbing and damping the parts. Note that most of the noise in the middle and high frequency ranges is absorbed by the sound absorbing layer.

In addition, by selecting a material with high surface density and rigidity for the restraining layer, a triple wall structure can be achieved, which can further improve sound insulation.

Therefore, all levels of noise from the low to high range transmitted from the engine compartment can be effectively insulated, and vibrations can also be significantly reduced, making the interior of the vehicle sufficiently quiet to ensure comfortable driving. It is guaranteed.

(Description of an embodiment) Hereinafter, an embodiment of an insulator dash according to the present invention will be described in detail based on the drawings.

In the figure, reference numeral 1 denotes a dash panel that partitions an engine room E and a vehicle interior R. This dash panel 1 consists of a darts lower 1a and a dash upper 1b, furthermore, the darts lower 1a is connected to a floor panel 2, and the dash upper 1b is connected to a cowl box 4 together with a cowl top 3.
form.

An insulator dash 5 according to the present invention is attached to the guide side of the dash panel 1. This insulator dash 5 includes a sound absorbing layer 6 made of felt, polyurethane foam, etc., a skin layer 7 having sound insulation properties such as rubber or soft vinyl chloride resin laminated on the sound absorbing layer, and a dash panel 1 side of the sound absorbing layer 6. It is composed of a viscous foam material layer 8 laminated on the viscous foam material I8, and a restraining layer 9 interposed between the viscous foam material I8 and the sound absorbing layer 6.

And these sound insulating skin layers 7. Sound absorbing layer 6. Restriction layer 9. The four layers of the viscous foam material layer 8 are cut and bent to match the surface shape of the dash panel 1, and are integrally molded on the plywood.

Note that the viscous foam material layer 8 is made of, for example, asphalt.

It is made by impregnating polyurethane foam or the like with a viscous material such as pitch, and the restraining layer 9 is preferably made of aluminum foil, a high-density rubber sheet, or the like.

With the above configuration, the noise and vibrations at the mid-range and low-range levels transmitted from the engine room E are absorbed and damped by the viscous foam layer 8, and the sound-absorbing layer 6, the sound is reliably absorbed and the interior of the vehicle R can be made quieter.

Here, as mentioned above, since the viscous foam layer 8 is sandwiched between the dash panel 1 and the restraining layer 9, vibrations are not transmitted to the sound absorbing layer 6 as in the conventional case, and the vibration damping effect is improved. is significantly improved.

In addition to the function of restraining the viscous foam layer 8 described above, the restraining layer 9 also significantly improves sound insulation properties. This means that dash panel 1. This is clear from the fact that a triple wall structure is formed by the three layers of the constraining layer 9° and the sound insulating skin layer 7.

[Brief explanation of the drawing]

The drawing shows one embodiment of the insulator dash according to the present invention, and is a sectional view showing a state where the insulator dash is attached to a dash panel. 1... Dash panel 5... Insulator dash 6... Sound absorbing layer 7... Sound insulating skin layer 8... Viscous foam layer 9... Restraining layer

Claims (1)

[Claims] (1) An insulator dash attached to the interior side of the dash panel, comprising a sound absorbing layer, a sound insulating skin layer laminated on the upper surface of the sound absorbing layer, and a viscous insulating layer laminated on the dash panel side of the sound absorbing layer. An insulator dash for an automobile, comprising a foam material layer, and a constraining layer is provided between the sound absorbing layer and the viscous foam material layer.