JP2872043B2 - Manufacturing method of foam molded product with core material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a foamed product with a core material, and more particularly, to the foaming molding with a core material, which ensures the positioning of the core material when setting the core material in a foaming mold. The present invention relates to a method for manufacturing a product.

[0002]

2. Description of the Related Art Vehicle interior parts such as instrument pads are usually formed by integrally molding a urethane foam layer on one side of a core material, and an upper mold (core mold) 1 is formed as shown in FIG. Using a foaming mold comprising a lower mold (cavity mold, hereinafter abbreviated as a mold) 2, a core material 3 is set on a core mold 1 as indicated by an arrow, and a skin is set on the mold, as shown in FIG. Foaming material for molding by injection equipment not shown,
For example, urethane is injected into the mold, and then the upper mold, that is,
The mold is formed by closing and foaming the core mold 1 and the lower mold, that is, the mold mold 2.

When the above-mentioned foamed article with a core material is integrally foam-molded, the positioning of the core material 3 is very important, and the core material 3 is positioned at a regular position on the core die 1 of the molding die. If not set properly, the accuracy of the finished product will vary greatly, making it difficult to satisfy a predetermined standard. This is because the core material 3 has a small variation in the molding, but the inner shape of the core material 3 and the gap for absorbing the variation of the core material are set in the core mold 1 of the molding die. This is because this gap reduces the product accuracy.

For this reason, as shown in FIG.
When the core material 3 is set in the core mold 1 by making a hole 5 in
It has been practiced to regulate the pin 4 of the core mold 1 to be inserted into the hole 5. However, such a method is inevitably performed at the time of integral foam molding because the hole 5 is formed in the core material 3. Since the urethane may leak from the holes 5, it is necessary to cover the holes 5 with a tape 6 beforehand, which leads to a complicated work process and an increase in product cost.

[0005] Therefore, further studies have been made on the improvement, and earlier, according to Japanese Patent Laid-Open No. 57-120421,
A method is proposed in which a coating is applied to the surface of the core material on the side where the foam layer is formed to cover the core material, and the core material set in the core mold is subjected to foam molding under the state covered with the coating. Was done.

[0006]

However, the method according to the above proposal not only increases the number of steps for applying the coating to the surface of the core material, but also increases the cost of materials such as adhesives and films. Becomes Further, although the pins can be moved in and out, there is a risk that the pins may make holes in the coating during foaming, and there is still a problem of leakage of the raw material.

[0007] The present invention addresses the above-described situation, and in particular, by finding a method of fitting a pin and a bush,
It is an object of the present invention to eliminate the need to close a hole for positioning with a tape, to reduce material costs and man-hours, and at the same time to enable a core material to be set with high accuracy.

[0008]

That is, a feature of the present invention that meets the above-mentioned object is that a core material is set in a foaming mold composed of a core mold and a mold mold, and a foaming material is injected and foamed. In manufacturing a foamed product with a core material in which a foam layer is integrally formed on one side of the core material, a pin is protruded at a predetermined position of the core material, and the pin position is provided on a core mold of the molding die. In this method, a bush is embedded by providing a hole, a pin of a core material is inserted into a bush of a molding die, set, injected with the foaming material, and foamed.

Here, the number of core pins is not limited to one.
A plurality of protrusions may be provided, and it is preferable to provide a plurality of protrusions particularly at a portion where accuracy is important.

The diameter of the pin is determined according to the size and weight of the foam molded product, the material of the core material, and the like. For example, in the case of an instrument panel, it is usually set to about 5 to 30 mmφ.

It is also effective to adjust the fitting tolerance of the bush hole to the pin or to make it a long hole depending on the required degree of accuracy of the portion.

[0012]

According to the present invention, first, the mold is opened, and the skin which is to be the surface of the molded product is set on the surface of the mold, and the pin of the core material is embedded in the hole of the core of the foaming mold. Insert the core material into the bush hole, regulate the position of the core material, and set the core material in the core type. At this time, both are accurately set by fitting the pin and the bush.

After injecting a foaming material such as urethane from an injecting device, the core mold and the mold are closed, and foaming is performed in accordance with a known method to obtain a foamed molded article with a required core material with high accuracy. .

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIGS. 2 and 3 show an embodiment of a main part in the production of a foamed article with a core according to the present invention.
1 is a core type, 2 is a mold type, 3 is a core material, and a pin 8 which is a feature of the present invention is provided on the core material 3 so as to protrude at a predetermined position. A hole is formed in a predetermined position of 1 and a bush 7 is embedded therein.
The pin 8 is inserted into the bush 7.

Here, the number of the pins 8 and the number of the bushes 7 are one each in the figure, but the number is not limited to one, and a plurality of the pins 8 and the bushes 7 are provided if necessary. In particular, it is preferable to set several places in a part where accuracy is important.

The pins 8 may be integrally formed of the same material as the core material 3, but pins of the same or different materials may be fixed to the core material 3 by bonding, screwing, or other appropriate means. .

The diameter of the pin 8, the bush hole or the hole diameter of the bush 7 is selected and determined each time in accordance with various factors such as the weight and size of the foamed product or the material of the core material 3. In the case of an instrument panel, for example, the diameter of the pin 8 is often set to 5 to 30 mmφ. On the other hand, the diameter of the bush hole is determined by adjusting the fitting tolerance with the pin depending on the required degree of accuracy of the portion. The bush 7 is not limited to a circular hole in cross section, but may have a long hole shape in cross section. In this case, some margin for adjustment is obtained.

In the drawing, reference numeral 9 denotes a skin made of a synthetic resin such as vinyl chloride which has been formed into a predetermined shape in advance, 10 denotes a foam layer made of a foam material such as urethane, and the skin 9 is used in the molding according to the present invention. After being set in the mold 2 and injecting a foaming material and then performing a foaming step, the material is integrally formed between the core material 3 and the skin 9, that is, on one side of the core material 3.

When an instrument panel is manufactured by the method of the present invention, the core member 3 is connected to the core mold 1 as shown in FIG. 1 and the pin 8 is connected to the bush 7 of the core mold 1 as shown in FIGS. After adjusting the position of the core material 3 and setting it accurately, a foaming material is injected onto the skin 9 previously set in the mold, and then the core mold 1 and the mold 2 are closed. After the foamed material is foamed by keeping it at 40 to 60 ° C. in an oven according to a known method, the foamed material foams between the skin 9 and the core material 3 and a predetermined foamed material is formed as described above. The layer 10 will be formed on one side of the core 3.

At this time, since there is no hole in the core material 3, no foam material (urethane) leaks out.
Leakage is prevented without the need to apply tape.

[0022]

As described above, according to the present invention, a pin is installed at a required position of a core material, a bush is embedded in a core mold of a foaming mold corresponding to the pin, and the pin of the core material is inserted into the bush. Is set in a foaming mold and foaming is performed. The core material can be accurately set in the foaming mold by fitting a pin and a bush, and the core material has a conventional hole. There is no foaming material such as urethane leaking out, so there is no need to close it with tape, reducing the cost of materials and man-hours, improving the economics, and obtaining an accurate molded product. Play.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a foaming mold used in the present invention.

FIG. 2 is a detailed cross-sectional view taken along the line AA in FIG.

FIG. 3 is an explanatory view schematically showing a main part of the present invention.

FIG. 4 is a schematic explanatory view showing a known core material setting mode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Core type 2 Mold type 3 Core material 7 Bush 8 Pin installed in core material 10 Foam layer

Claims (1)

(57) [Claims] 1. A foam with a core material, in which a core material is set in a mold having a core mold and a cavity mold, and a foam material is injected and foamed to form a foam layer integrally on one side of the core material. In the method of manufacturing a molded product, a pin is protruded at a predetermined position of the core material, and a bush is provided in the core mold of the molding die corresponding to the pin position, a hole is provided, and a pin of the core material is formed in the molding die. A method for producing a foamed molded product with a core material, comprising inserting the foamed material into the bush, setting and injecting the foamed material, and performing foaming.