JPH0629130Y2 - Vehicle insulator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a vehicle insulator installed in a floor panel, particularly below a rear seat.

[Prior Art] FIG. 3 shows a vehicle insulator, in which a sub-muffler 2 is loaded especially below a rear seat 1, and the sub-muffler 2 is used as a heat source to directly heat a floor panel portion 3 and to be installed here. The insulator 6 is shown.

The insulator 6 is a double-layered body in which the floor panel portion 3 is easily heated and thus is provided with sound insulation and heat insulation properties, and the sound insulation layer 5 is attached on the heat insulation layer 4. The heat insulation layer 4 is made of felt, and the sound insulation layer 5 is made of recycled vinyl chloride sheet, rubber sheet, or the like.

[Problems to be Solved by the Invention] However, if felt is used as the heat insulating layer 4, it is likely to be thermally deteriorated and easily deformed under a load. Therefore, alternative materials have been studied. Glass wool was considered as an alternative to felt, but it could not be used because of its excellent heat resistance and moldability, especially because of its large thickness variation.

In addition, the actual exploitation Sho 61-147650 and the actual exploitation Sho 62-16.
It is also possible to consider a substitute material with reference to the soundproof material structure shown in No. 2149 or the like.

The former is a double layered product in which a foam layer is attached on a compressed urethane foam material. The foam layer is made of urethane foam, etc.,
Insulates high frequencies exclusively. The compressed urethane foam material is designed to insulate low and medium frequencies by impregnating viscous substances.

The latter is a technique for obtaining adhesiveness with a panel in the former double laminated body. A sound-insulating layer (a thermoplastic resin sheet) is attached on a sound-absorbing layer (foam) to form a double-layered structure, and a latex layer is further formed on the lower surface of the sound-absorbing layer to form a triple-layered structure. A magnetic powder is mixed in the latex layer to magnetically adhere to the panel side.

Both foams are for the purpose of obtaining a sound insulation or sound absorption effect, and the heat insulating property like glass wool cannot be expected at all. Further, since these foams are not located on the panel side, no consideration is given to the thermal conductivity, and the thermal conductivity is high.

The present invention solves the above problems, and its purpose is to improve the foam layer for heat insulation, formability, and for vehicles that are optimal for installation below the rear seat due to being difficult to deform under load. To provide an insulator.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a floor panel located below a rear seat, which comprises a double-layered body in which a sound insulation layer is adhered on a heat insulating foam layer. A vehicle insulator to be installed, wherein the foam layer has a foaming ratio of 20 to 40 times using polyethylene foam, and
The gist is that 50% or more of the total volume is composed of a closed cell structure and the thermal conductivity is 0.03 kcal / mh ° C or less.

[Operation] According to the configuration described above, in addition to specifying the polyethylene foam in the foam layer, by numerically limiting the expansion ratio and the closed cell structure, it is possible to obtain the same heat insulating property as that of glass wool. found. This foam layer is
Compared to felt and glass wool, it has excellent moldability and economy, and its stable thickness makes it ideal for floor panels located below the rear seats.

[Embodiment] Hereinafter, one embodiment of a vehicle insulator according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a side cross-sectional view showing a usage state of the vehicle insulator of the present application, in which an insulator 13 is installed under a rear seat 10, that is, between a lower surface of a seat cushion 11 and a floor panel 12. This thin insulator 13
Is a double layered body of a foam layer 15 and a sound insulating layer 14 having a relatively high surface density such as a recycled vinyl chloride sheet or a rubber sheet. The difference from the conventional one is that the foam layer 15 is improved.

The foam layer 15 is made of polyethylene foam and easily forms a closed cell structure. It was expected that this closed-cell structure would be superior to the open-cell structure in terms of heat insulation and sound insulation. It was found that the adiabatic effect and the sound insulation effect are remarkably improved when the cell structure is smaller than that of the cell structure.

An example of the result of this experiment is shown in Table 1 below.

In Table 1, PEF is polyethylene foam,
Polyurethane is polyurethane foam and polystyrene is polystyrene foam. The closed cell structure is about 50% in each foam.

The results of other experiments are shown in the graph of FIG. This graph is an example of how the thermal conductivity changes depending on the expansion ratio. The foam is polyethylene foam and the closed cell structure is about 50% of the total volume.

As is clear from this graph, the thermal conductivity greatly fluctuates depending on the expansion ratio, and when the expansion ratio becomes 15 times or more, it rapidly increases. Therefore, the expansion ratio of the foam layer 15 may vary depending on the foam molding conditions and the like.
It is preferably set to 20 to 40 times. In this range, the thermal conductivity is 0.03 kcal / mh ° C or less, which is the best heat insulating property. It has the same heat insulating property as glass wool, and since it is a foam, it has a stable thickness and is difficult to be crushed even under a load.

[Effects of the Invention] As described above, in the vehicle insulator according to the present invention, although the glass wool is pointed out as a heat insulating property due to the improvement of the foam layer, it is difficult to be deformed due to the moldability and the load. A double-layered product that is optimal for installation in

[Brief description of drawings]

FIG. 1 is a side sectional view showing an installed state of a vehicle insulator according to the present invention, and FIG. 2 is a graph showing a relationship between a foaming ratio and a thermal conductivity of polyethylene foam used as a foam layer of the present invention. FIG. 3 and FIG. 3 are side sectional views showing a conventional vehicle insulator. 10 ... Rear seat 11 ... Seat cushion 12 ... Floor panel 13 ... Insulator 14 ... Sound insulation layer 15 ... Foam layer.

Claims (1)

[Scope of utility model registration request] 1. An insulator for a vehicle, which comprises a double-layered body in which a sound insulation layer is adhered on a heat insulating foam layer and is installed on a floor panel located below a rear seat, wherein the foam layer is The polyethylene foam is used to have a foaming ratio of 20 to 40 times, 50% or more of the total volume is composed of closed cell structure, and the thermal conductivity is 0.03 kcal / mh ° C. or less. Vehicle insulator.