JPH0373321A - Mold of different hardness cushioning body - Google Patents

Abstract

PURPOSE:To manufacture a different hardness cushioning body from a liquid foaming stock by a method wherein the interior of a cavity is divided by a net-like or lattice-like partition into a cavity, in which softer part is molded, and a cavity, in which harder part is molded. CONSTITUTION:A supporting part 132, by which a partition 130 is supported when a mold is closed, is provided on an upper lid 110. In a lower mold 120, the partition 130, which is made of net-like material such as victoria lawn, is fixed by pressure sensitive adhesive to fixing parts 131 so as to divide a cavity a1, in which softer part is molded, from a cavity a2, in which harder part is molded. The liquid foaming stock, which is poured in the cavity a1 of a mold 100, starts to expand so as to fill the cavity a1 and form the softer part and, at the same time, flows through the meshes of the net 6 of the partition 130 into the cavity a2. The growth of the bubbles of the liquid foaming stock flowing in the cavity a is limited and their shapes become uniform and their film thicknesses become thicker. Accordingly, the hardness of the stock in the cavity a is higher than that of the stock in the other part so as to form the harder part of a cushioning body after the finish of gas blowing reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a mold for forming a cushion body of different hardness, which is used to manufacture a cushion body of different hardness that partially has different hardness.

(Prior Art) Cushion bodies are often used in furniture, seats in vehicles, etc., but cushion bodies with partially different hardness are required for seats in vehicles to improve the ability to hold occupants. Became.

Conventionally, to manufacture cushion bodies of different hardness, a mold is used in which the cavity is divided by a partition into a cavity for molding the hard part and a cavity for molding the soft part, and the cavity for molding the hard part and the cavity for molding the soft part are used. Different liquid foaming raw materials are injected into cavities for molding soft parts and foamed without mixing to produce a cushion body with different hardness having hard parts and soft parts.

In addition, in order to prevent the hard and soft parts of the cushion body of different hardness from separating during the manufacturing process, a partition is provided protruding from the cavity surface at the bottom, and an uneven partition that divides the cavity of the lower mold is provided on the upper mold cavity. It is possible to use a mold having a structure in which cavities are separated by partitions of the upper and lower molds, and the separated cavities are communicated with each other by the uneven shape of the partitions provided on the upper mold cavity surface. It has been proposed (Japanese Unexamined Patent Publication No. 56-1
Publication No. 9734).

<Problems to be Solved by the Invention> However, in the above-mentioned molding mold, two types of liquid foaming raw materials with different compositions must be injected into the cavity of the molding mold, and the injection work, blending work, etc. are troublesome. There is also the problem that raw materials cannot be rationalized.

Therefore, in view of the above-mentioned points, the present invention aims to provide a molding die that can manufacture cushion bodies of different hardness from a single liquid foaming raw material.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention provides a cushion body of different hardness in which the inside of the cavity is divided by a partition into a cavity for molding a soft part and a cavity for molding a hard part. In this mold, the partition was made of a knitted material or a lattice-like material.

(Function) In the molding mold of the present invention, a predetermined liquid foaming raw material is injected into the cavity in which the soft portion is to be molded when manufacturing a cushion body of different hardness. The liquid foaming material injected into the cavity for molding the soft part fills the cavity for molding the soft part by expansion due to the foaming reaction, and further passes through the mesh or lattice-like material partitioning the cavity of the mold. , flows into the cavity forming the adjacent hard part. At this time, the flow of the liquid foaming raw material is disturbed by the mesh of the net or the lattice part of the lattice, restricting the growth of bubbles, and forming a non-uniform bubble inside the cavity where the hard part is formed. Inflow. Therefore,
The cushion body obtained by completing the foaming of the liquid foaming raw material is made up of normal cells that are foamed normally in the cavity that molds the soft part, whereas the cushion body that is obtained by foaming is formed in the cavity that molds the hard part. The molded part is hard and consists of non-uniform bubbles with limited bubble growth, creating a cushion body with different hardness.

(Example) Examples of the present invention will be described below.

Fig. 1 is a partially cutaway perspective view showing a mold for forming a cushion body of different hardness (hereinafter referred to as the mold) according to an embodiment of the present invention, and Fig. 2 shows a partition made of a net-like material attached. FIG. 3 is a perspective view of the previous mold.

The mold 100 is used for manufacturing a seat cushion body, and consists of an upper mold 12110, a lower mold 120, and a partition 110. The lower mold 120 includes a locking portion 131 for locking a partition 130 made of a net-like material such as cheesecloth,
A support portion 132 is formed on the upper lid 110 to support the locked partition 130 when the mold is closed. Also partition 130
is locked to the locking part 131 of the lower mold via an adhesive, and divides the inside of the cavity into a cavity a1 for molding a soft part and a cavity a2 for molding a hard part. In addition, 1
50 indicates a vent hole, and when manufacturing the cushion body,
This is to allow the air inside the mold to escape and to prevent the formation of missing parts in the cushion body. The diameter, position, and number of vent holes are determined depending on the product shape, but it is best to position them at the edges of the product so that the liquid foaming material can spread easily and reach every corner of the cavity. This is desirable for distributing the liquid foaming raw material until the end.

Next, a method for manufacturing a cushion body of different hardness using this mold 100 will be explained.

(a) First, a liquid foam raw material, such as a polyurethane foam raw material, which is a raw material for manufacturing a cushion body, is injected into the cavity a in which the soft portion of the lower mold 120 is to be molded.

(b) After injecting the liquid foaming raw material, the top 12110 is closed.

(c) The liquid foaming raw material injected into the mold starts foaming and fills the cavity a1 in which the soft portion is to be molded, thereby forming the soft portion of the cushion body and forming the net-like material forming the partition 130. The adjacent cavity, that is, the cavity a that molds the hard part, passes through the mesh of
, begins to flow inward.

At that time, the reaction of the liquid foaming raw material has already progressed, so the bubbles grow to some extent and pass through the narrow mesh with increased viscosity.
The flow of Fl is disturbed due to large resistance, restricting the growth of bubbles and making the shape of the bubbles non-uniform. Then, the liquid foaming raw material with non-uniform bubbles flows into the cavity a2 in which the hard part is molded.

(iv) Molding the hard part The liquid foaming raw material that has flowed into the cavity a2 completes foaming and molds the hard part of the cushion body. In the hard part of the cushion body, the growth of bubbles is restricted as described above, the shape of the bubbles is non-uniform, the thickness of the bubble is thicker, and the hardness is higher than in other parts.

<Bo> After the foaming reaction is completed, the cushion body is demolded to obtain a cushion body with different hardness.

The partition 130 is locked by a locking part 131 on the side of the cavity where the soft part is molded, and is supported by the locking part 131 and the support part 132 from the side of the cavity where the hard part is molded when the liquid foaming raw material is foamed. . For this locking, supplementary locking using a bottle or the like may be added as necessary.

In addition to cheesecloth, a variety of other materials can be used for the partitions, such as a grid made of synthetic resin or wire mesh.
Since it is embedded inside the product, it is necessary to decide the hardness of the partition and the size of the mesh or lattice depending on the product.

FIGS. 3 and 4 are perspective views showing a mold 200 according to another embodiment of the invention. In the molding die 200, a lower die 220 combined with an upper N (not shown) is a third
As shown in the figure, it is divided into 221 and 222, and after a cheesecloth partition 230 is inserted into the divided part, the divided parts are brought together as shown in Figure 4, and a cavity a is formed for molding the soft part, and a cavity a is formed for the hard part. The molding cavity is divided into a molding cavity a, and a molding cavity a. The portion of the partition 230 that protrudes from the cushion body of different hardness is removed after the cushion body of different hardness is molded.

In addition to the molding molds shown in the above embodiments, there are also molding molds in which a mesh or lattice-like material is fixed to the opening of a plate-shaped body in which openings such as holes are formed in a part of the product. It is used depending on the shape etc.

Further, the net-like or lattice-like partitions may be constructed by providing grooves or the like in the mold and fitting the partitions into the mold, and allowing the partitions to be freely removed.

Also, in the above embodiment, the partition was -, but
We set up two partitions to divide the inside of the cavity into three parts,
The center part may be used as a cavity for molding the soft part, and the sides thereof may be used as cavities for molding the hard part.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a molding die according to an embodiment of the present invention with a part cut away; FIG. 2 is a perspective view of the mold before a partition is attached to the mold; FIGS. FIG. 4 is a perspective view of a molding die according to another embodiment of the present invention. 100, 200: Molding mold, 110: Upper lid, 120
, 220: Lower mold, 130, 230: Partition, 1
50: Vent hole, a: Cavity for molding the soft part, a2: Cavity for molding the hard part Figure 1

Claims (1)

[Claims] A cavity that molds a soft part inside the cavity,
1. A mold for molding a cushion body of different hardness, the mold having a cavity for molding a hard part separated by a partition, wherein the partition is made of a knitted material or a lattice-like material.