JPH03132318A - Molding method for padding material - Google Patents

Abstract

PURPOSE:To adjust elasticity of a desired section of a padding material of any kind of shape and mold integrally with a frame by blowing air into the mold immediately after foaming and filling a foaming raw material into the mold and forming a space. CONSTITUTION:A frame 5 for a front seat back 1 for a car provided with a plate 2 and a spring 6 is disposed in molds of a top force 7 and a bottom force 8, and polyol and isocyanate are injected therein. At the time when foaming is completed and the foaming strength is still weak and soap-like foams are produced, the given quantity of air is blown from the end of a nozzle 13 running through an opening provided on a plate 2 mounted on the top force 7 and inserted into a urethane pad 3 to destroy foam cells and form a space 14 in the urethane pad 3. As said space 14 is encircled with a resin film 15 composed of destroyed foam cells, a deflected space section 14 without bottomed feeling and with proper elasticity can be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for molding a pad material, and more particularly to a method for molding a pad material having a space inside.

[Conventional technology]

Pad materials made of foamed materials, such as polyurethane foam, are widely used as cushioning materials in various automotive fields, and are also frequently used as interior materials for automobiles. Various methods are used to mold pad materials depending on their properties and uses, but for example, in the molding of front seat backs for automobiles, the front seat pack 1-metal production efficiency as shown in Figure 3 has recently been developed. In order to achieve good results, integral foam molding is often used. In the figure, 2 is a plate, 3 is a urethane pad, 4 is a headrest stay, and 5 is a frame. The front seat back 1 has an upper mold 7 as shown in FIG.
The frame 5 with the plate 2 and the springs 6 is placed in a mold consisting of a lower mold 8 and a polyurethane raw material is injected, foamed and cured, and then integrally molded with the urethane pad 3.

[Problem to be solved by the invention]

Conventionally, as shown in FIG. 5, a protective plate 2 is provided to prevent the knees 10 of the occupant 9 in the rear seat from hitting the headrest stay 4. However, because of this plate 2, it is not possible to freely adjust the elasticity of the backrest 11 shown in FIG. It ends up. For this reason, there has been a demand for a molding method that can clearly adjust the elasticity of desired portions even when integrally molding a pad material having the plate 2 and the like as described above.

The present invention is intended to solve the problems in the prior art. The purpose is to provide a method that allows a pad material made of a foam material of any nature to be molded integrally with a frame by adjusting the elasticity of a desired portion.

[Means to solve the problem]

In other words, the method for molding the pad material of the present invention involves injecting a foaming raw material into a mold, and immediately after the foaming raw material foams and fills the mold, air is blown into a desired position in the mold to fill the space. It is characterized by the formation of

The foaming raw material may be any material that can be foamed in a mold to form a foam material. Specifically, examples include materials that foam by reaction, such as polyurethane raw materials, and resin compositions made of a resin such as polyethylene and a foaming agent.

Polyurethane raw materials are particularly preferred from a practical standpoint.6 For example, when using polyurethane raw materials, the polyurethane raw materials may be polyols and incyanates that are commonly used in this field, and the properties such as the size and shape of the pad material are not particularly limited.

A nozzle is used to blow air.

A suitable number of nozzles Fi may be provided integrally at a predetermined position of the mold, or may be provided separately from the mold. Properties such as the size and shape of the nozzle are appropriately selected depending on the position, volume, shape, etc. of the space to be formed. It is convenient to provide the nozzle with a check valve to prevent the foaming material from flowing backwards when air is blown into the nozzle. It is best to provide a sealing groove between the mold and the nozzle. For example, if this groove is self-sealed with foamed raw material, workability is improved.

The size and shape of the space formed within the padding material are determined by taking into consideration the desired degree of elasticity adjustment, the size and shape of the padding material, etc. For example, when forming a space near the plate of a pad material having a grating, the plate acts as a barrier to suppress the spread of blown air in a predetermined direction. can be formed.

The air is blown at a time immediately after the foaming raw material has foamed and filled the mold, but when curing has not yet been completely completed. Since it is not possible to form the desired space once curing is completed, the optimum timing for blowing air is determined in advance through experiments or the like.

[For production]

If air is blown into the foaming material when it has foamed and not yet completely cured, the foamed structure in the blown area will be destroyed and become a resin film, and a space surrounded by this resin film will be formed. The elasticity of the desired part can be adjusted by adjusting the space between the ribs.

〔Example〕

The invention will be explained in further detail by the following examples. Note that the present invention is not limited to the following examples.

A frame 5 for an automobile seat back equipped with a plate 2 and a spring 6 was placed in a mold consisting of an upper mold 7 and a lower mold 8 shown in FIG. 1, and polyol and isocyanate were injected. .

At the time when foaming is completed, the foam strength is still weak and the foam resembles soap foam. At this time, when a predetermined amount of air is blown from the tip of the nozzle 13, which is attached to the upper die 7 and inserted into the urethane pad 3 through a hole made in the plate 2, as shown by the arrow in the figure, the foam cell is destroyed and the urethane Space W according to the amount of air blown into pad 3
514 is formed. Since this space 14 is surrounded by a resin film 15 made of destroyed form cells, the flexure space 1 maintains appropriate elasticity without feeling bottomed out.
It is possible to produce 4.

FIG. 2 shows an enlarged view of the vicinity of the tip of the nozzle 13 shown in FIG. 1. A ball-shaped check valve 161fr is installed at the tip of the nozzle 13 to prevent the polyurethane raw material in the process of foaming from entering the nozzle 13, and also to prevent the polyurethane raw material from leaking from between the upper mold 7 and the nozzle 13. A self-sealing groove 17 was provided as shown in FIG.

When the urethane pad 3 is cured after forming the space 14, the front seat back 1 having the space 14 on one side of the plate 2 is obtained.

〔Effect of the invention〕

As described above, the method for molding the pad material of the present invention involves injecting a foaming raw material into a mold, and immediately after the foaming raw material foams and fills the mold, air is blown into a desired position within the mold. In order to form a space, a flexure having appropriate elasticity is formed at a desired position of the pad material.

Further, since the volume of the air space can be changed by changing the amount of air and the timing of air blowing, the degree of elasticity can be easily adjusted. In addition, air can be blown using a nozzle with a simple structure, and there is no need for a core or mold with a complex structure.Furthermore, the position and number of nozzles can be changed freely. By this, a pad material having desired elasticity can be easily obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an embodiment of the pad material molding method of the present invention, FIG. 2 is a partially enlarged view of FIG. 1, FIG. 3 is a partially cutaway perspective view of a conventional front seat back no. FIG. 4 is an explanatory diagram of a method of forming the front seat back of FIG. 3, and FIGS. 5 and 6 are explanatory diagrams of problems with the front seat back of FIG. 3. In the diagram, 1...Front seat back 2...Plate 3.
・・Urethane pad 4・Headrest stay 5・
...Frame 6...Spring 7...Upper mold 8...
Lower mold? ...Crew member 10...Knee 11...Backrest
12... Back 13... Nozzle 14... Space 15... Resin membrane 16... Check valve 17... Clearance diagram 5 4 No. 1 front seat back diagram negative diagram

Claims (1)

[Claims] A pad material characterized in that a foaming raw material is injected into a mold, and immediately after the foaming raw material foams and fills the mold, air is blown into a desired position in the mold to form a space. Molding method.