JPH0336009B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method of manufacturing an integrally foamed molded product, in which a pad portion is integrally foam-molded with a foam material inside a cover member such as a headrest.

BACKGROUND ART Conventionally, for example, when manufacturing a head rest, etc., a head rest cover is blow molded from a parison, and during the blow molding, the upper end of the shaft of a stay is inserted into the parison in advance, and the head rest cover is inserted into the parison after the blow molding. The head rest cover and the pad part are integrated to form a head rest with the stay protruding by molding the pad part by foaming and hardening the foam material filled in the rest cover and fixing the upper end of the shaft of the stay with the pad part. things are being done.
However, in this headrest, when the foam material expands in volume by foaming, the air that was pushed into the cover by foaming near the corners of the cover and the foaming gas that was not captured by the foam material during foaming are removed. If the cover is allowed to stagnate and harden, creating a hollow part where there is no part, and if holes are made using a needle at each corner of the cover to exhaust the gas, the foam material such as urethane foam may be removed at the same time. is likely to seep out from the pores, staining the epidermis, and causing a significant loss of commercial value.

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a method for manufacturing an integrally foamed molded product that can be foam-molded without producing the above-mentioned hollow portions.

That is, in the method for manufacturing an integrally foamed molded product according to the present invention, a porous baffle plate is supported by an axial member such as a stay inserted into a cover member to be molded, and the baffle plate supports the metal of the cover member. By guiding the foaming flow of the foam material filled into the cover member after molding to the corner portion of the cover member,
It is possible to reliably fill and mold the foam hardened layer of the foam material in the corner portion.

Embodiments Hereinafter, a detailed description will be given with reference to the drawings.

In the illustrated embodiment, a case is shown in which a substantially horseshoe-shaped headrest having a cavity in the center is manufactured as an integrally foamed molded product. In this headrest, a corner portion 3 near a rectangular end surface of a rising portion 3 that projects a stay 2 from a cover member 1 is provided.
Since a gap 4' where no part 4 is present is likely to be formed at part a, a rectangular baffle plate 5 corresponding to the cross-sectional shape is installed and fixed on the axis of the stay 2 at the rising part 3, and the baffle plate 5 is By forcibly moving and guiding the foaming flow of the foam material in the direction of the corner portion, the formation of a void portion 4' is prevented (see FIGS. 1 and 2). As the baffle plate 5, a net-shaped one as shown in the third figure is used.
This net 5 is 3 to 5 mm larger than the planar area of the rising portion 3.
It is possible to use a type having a relatively narrow width or a type having approximately the same area, and the stay 2 is mounted and fixed on the axis with a narrow distance between it and the bottom part 3b of the rising part 3 (see Fig. 4). ).

Blow molding can be applied to mold the headrest. The blow molding mold 6
is equipped with split molds 6a and 6b on the left and right, and each split mold 6
It has a base 6c on which a and 6b are placed facing each other. The base 6c has a valve 7a in the center for discharging compressed air, and brackets 7b and 7c for mounting the stay 2 integral with the headrest frame 2a are provided on the left and right sides of the valve 7a (see FIG. 5).

Using this mold 6, first the stay 2 with the net 5 attached and fixed on its axis is placed on the bracket 7.
The parison forming the cover member 1 is then extruded from the die head into a cylindrical shape with its lower end open, and the base 6c is assembled so that the head rest frame 2a and the stay 2 are received inside the parison. Place it on top. Thereafter, the parison is clamped and fixed between the split molds 6a and 6b. After the mold 6 is clamped and fixed, compressed air is supplied into the parison from the valve 7a of the base 6c to form the cover member 1 having a desired three-dimensional shape. Thereafter, the cover member 1 molded into a three-dimensional shape is removed from the mold 6, and the inside is filled with the foam material 8. When filled with the foam material 8, the cover member 1 is inverted so that the stay 2 protrudes upward so that the foam material 8 stays inside the top of the cover member 1 (see Fig. 6). Foam. Along with this foaming, the foam material 8 gradually increases in volume and rises, and when it rises close to the net 5, the foaming flow flows through the narrow mesh 5a of the net 5 and between the net 5 and the cover member 1. The foaming flow passes through the gaps, and the foaming flow passing through the meshes 5a comes into contact with the bottom 3b of the rising portion 3 and rapidly moves within the gap toward the gap corner 3a of the rising portion 3, and the foaming flow passes through the gaps. The flow also moves toward the corner 3a (see FIG. 7). At that time, the foaming gas flows through the bottom 3 of the rising part 3.
The gas can be discharged from a gas vent hole 3c formed approximately at the center of b, and the gas vent hole 3c is formed by integrally molding a gas vent pipe during blow molding, or is simply formed by perforating or the like. Good too.

In the above-described embodiment, the net 5 is inserted in advance when the cover member 1 is molded, but it may be attached to the shaft line member such as the stay 2 after the cover member 1 is molded. Further, in this embodiment, a head rest having rising portions 3 corresponding to the left and right stays is shown, but the present invention can also be applied to the molding of a head rest having a general trapezoidal shape. In that case, one net is installed between each stay, and the foam flow of the foam material can be moved and guided at each corner of the square. Furthermore, it can be applied not only to the production of headrests, but also to the production of various foam molded products.
As the member for mounting and arranging, it is possible to use not only a stay that protrudes from the cover member 1, but also a frame that is embedded in the foam material.

In this way, if the foaming flow of the foam material is forced to pass through the mesh and gaps of the baffle plate 5 and move toward the gap corner of the rising portion 3, the foaming gas that tends to stay will be pressed and moved, and the appropriate gas will be released. Since it can be discharged from the punched part, it is possible to form a patch part 4 without any missing parts. Further, the baffle plate 5 can be impregnated with a foam material into its holes and finally hardened integrally with the pad portion.

Effects of the Invention According to the method for manufacturing an integrally foamed molded product according to the present invention, the foam flow of the foam material is rapidly passed through the holes of the porous baffle plate and the gap between the baffle plate and the cover member. By guiding the movement to the part, the foaming gas that tends to accumulate can be forcibly pressed and the foam material can be filled even in the corner part, so it is possible to prevent damage to the part part, and when manufacturing products such as headrests. By using the baffle plate as a support plate, a support shaft member such as a stay can be firmly fixed integrally with the part.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a headrest as an example of the integrally foamed molded product manufactured by the present invention, Fig. 2 is an explanatory view showing problems in manufacturing the headrest, and Fig. 3
The figure is a perspective view of a baffle plate used in the method according to the present invention,
FIG. 4 is an explanatory diagram showing the position of the baffle plate used in the same method, FIG. 5 is an explanatory diagram of the mold used in the same method,
6 and 7 are partially enlarged side views showing the foaming flow of the foam material. 1: Cover member, 2: Axis member such as stay, 3
a: corner portion, 5: baffle plate, 6: mold, 8: foam material.

Claims (1)

[Claims] 1. A porous baffle plate is supported by an axial member such as a stay that is inserted into the cover member to be molded, and the baffle plate controls the foaming flow of the foam material to be filled into the cover member after molding the cover member. A method for manufacturing an integrally foamed molded product, characterized in that the movement is guided to a corner portion of a cover member.