JPH0249611B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an integral foam molding method for a headrest in which a foaming liquid is injected between a combination of an impermeable skin material, a core material, and a stay to form foam.

FIG. 1 and FIG. 2 show a conventional technique for integral foam molding of a headrest.

In this prior art, a non-breathable skin material 2 is installed inside a foaming mold 1, and a gas venting hole 2a is formed in the skin material 2 at a position opposite to a gas venting hole 3 of the foaming mold 1. A combination of a core material 4' and a stay 5' is inserted inside the skin material 2, and an insert material 6 having air permeability such as slab urethane is attached between the gas vent hole 2a and the core material 4'. A foam stock solution 9 is injected between the combination of the material 2, the core material 4', and the stay 5', and the gas is released from gas vent holes 3 and 2a penetrating the foam mold 1 and the skin material 2. .

However, in the conventional technology, gas is vented only from the gas vent holes 3 and 2a, which has the disadvantage that gas venting during foaming is poor, resulting in formation of cavities in the foam and inhibition of foaming. If an excessive amount of the stock solution 9 is injected, burrs may be ejected from the gas vent holes 3 and stain the skin material 2. Also, due to insufficient gas venting, abnormal expansion may occur during demolding. There is also the drawback that the foam may become deformed. Note that c in FIG. 2 indicates the burr discharge direction.

An object of the present invention is to provide an integral foam molding method for a headrest that can effectively extract the gas generated from the foam and the internal air due to the increased volume of the foam, and will be described in detail below with reference to the drawings.

FIG. 3 shows an embodiment of the present invention, in which a non-breathable skin material 2 is installed inside a foam mold 1, and a combined body of a core material 4 and a stay 5 is arranged inside the skin material 2. .

The foaming mold 1 has one half 1a and the other half 1b, 1.
It is constructed by combining c.

The foam mold 1 and the skin material 2 are provided with gas vent holes 3 in the foam mold 1 and gas vent holes 2a in the skin material 2 so as to penetrate from the inside of the skin material 2 to the outside of the foam mold 1.

The core material 4 is formed hollow, and has ventilation holes 7 formed at its upper and lower ends, and furthermore, a pipe insertion hole 8 is formed at the end of the skin material 2 facing the gas vent hole 2a. .

The stay 5 is formed of a pipe with one end (lower end in FIG. 3) closed and the other end open, but it may also be a simple rod-shaped body.

The end portion of the skin material 2 is formed into a half portion 1a of the foaming mold 1.
An insert material 6 made of soft slab urethane or the like is installed inside the skin material 2 along this mold matching surface.

A gas vent pipe 11 is inserted into the gas vent hole 3 of the foam mold 1, the gas vent hole 2a of the skin material 2, and the pipe insertion hole 8 of the core material 4, and the gas vent pipe 11 is inserted into the gas vent hole 3 of the foaming mold 1, the gas vent hole 2a of the skin material 2, and the pipe insertion hole 8 of the core material 4.
It is formed in a state of communication with the outside. The gas venting pipe 11 has an appropriate diameter depending on the foaming pressure of the foam stock solution 9 injected between the skin material 2 and the core material 4.

Therefore, a non-breathable skin material 2 is installed inside the foam mold 1, a combination of the core material 4 and the stay 5 is inserted inside the skin material 2, and an insert material 6 is placed along the end of the skin material 2. Then, insert the gas vent pipe 11 into the gas vent holes 3 and 2a and the pipe insertion hole 8,
When a part 1c of the foaming mold 1 is opened and a stock solution 9 of the foam is injected into the space formed inside the skin material 2 and between the combined body of the core material 4 and the stay 5, the stock solution 9
As shown by arrow a in FIG. 3, the foam is sequentially foamed and filled upward from the bottom.

At this time, the gas generated from the foam stock solution 9 and the internal air due to the increased volume of the foam flow into the interior of the core material 4 through the ventilation holes 7 of the core material 4, as shown by arrow b in FIG. Next, the foam mold 1 is passed through the gas vent holes 2a and 3 through the gas vent pipe 11 inserted into the pipe insertion hole 8 of the core material 4, as shown by the arrow c.
extracted to the outside.

Further, an excessive amount of the foam stock solution 9 is impregnated and absorbed into the insert material 6, or is discharged into the core material 4 through the ventilation hole 7, and is prevented from being discharged from the gas vent hole 3 of the foam mold 1.

After the foaming of the foam is completed, one half 1a and the other halves 1b and 1c of the foaming mold 1 are opened to form an integrally foamed product 21 of the skin material 2, foam, core material 4, and stay 5 as a product. Remove the mold. After demolding, degassing pipe 1
Pull out 1 or cut the protrusion.

The above is an embodiment of the integral foam molding method for a headrest according to the present invention. According to this method, most of the generated gas of the foam and the internal air due to the increase in the volume of the foam are removed from the core material. The gas is introduced into the core material through the ventilation hole provided in the core material, and then extracted to the outside of the foam mold through the gas vent pipe inserted into the pipe insertion hole of the core material. This has the effect of preventing the formation of bubbles and poor foaming.

Further, according to the present invention, even if the injection amount of the foam stock solution is excessive, it is possible to prevent burrs from being discharged from the gas vent hole, and deformation due to abnormal expansion of the foam during demolding is achieved. It also has the effect of preventing

It should be noted that the above description merely shows one embodiment of the present invention, and it will be obvious that various modifications and changes can be made without departing from the spirit of the present invention.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view for explaining the conventional technology;
FIG. 2 is an enlarged view of part A in FIG. 1, FIG. 3 is a longitudinal sectional view for explaining one embodiment of the present invention, and FIG.
The figure is a perspective view of a headrest manufactured according to the present invention. In the figure, 1... foam type, 2... skin material, 2a...
Gas vent hole in skin material, 3... Foaming type gas vent hole, 4... Hollow core material, 5... Stay, 6... Insert material, 7... Ventilation hole, 8... Pipe insertion hole, 9 . . . Foam stock solution, 11 . . . Gas venting pipe, 21 . . . Head rest as an integral foam molded product.

Claims (1)

[Claims] 1. A non-breathable skin material is attached to the inside of the foam mold, and a combined body in which the stay of the headrest and the core material are integrally bonded to one side of the tip of the head rest is placed inside the skin material. In the integrated foam molding method of the headrest, in which a foam stock solution is injected into the inside of the foam mold and foamed, a gas vent hole is formed by penetrating the foam mold and the skin material, and a vent hole and a pipe insertion hole are formed in the core material. A gas vent pipe is inserted into the gas vent hole and the pipe insertion hole, and gas generated from the foam generated between the skin material and the core material is introduced into the core material through the vent hole of the core material. An integral foam molding method for a headrest characterized by extracting gas from inside the core material to the outside of the foam mold through a gas vent pipe.