JPS61146514A - Manufacture of cushion body - Google Patents

Abstract

PURPOSE:To enable the number of processes to be reduced, contriving to obtain the cushions in which the foams with different hardnesses are laminated in one time foaming by reaction-curing each foaming stock solution, after the partition plates inserted in a mold have been rapidly drawn out and the openings of the mold have been closed. CONSTITUTION:Partition plates 2 are inserted into a mold. Different foaming stock liquids A, B are poured into the foaming chambers having been partitioned, and the inside of the mold is sealingly closed, covering 5 them from their upsides, and then, both foaming stock solutions are foamed simultaneously. Before this reaction is finished and said solutions are cured, the partition plate 2 is drawn out. This drawing out is rapidly carried out, whereby each foam to be foamed in the mold does not mix one another, and each stock solution is foamed with its characteristic, and further the characteristic of each foam is expressed as it is. After the partition plates 2 have been drawn out, a cramp 7 is fitted to the upper surface of the cover at the opening portion 6, and the opening portions 6 are closed, thereby preventing the flowing out of the foam and reaction-curing the foaming stock solution in the mold 1.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to vehicle seats such as automobiles or furniture chairs;
Concerning the manufacturing method of cushion bodies used for beds etc.
In particular, the present invention relates to a method of manufacturing a cushion body formed by simultaneously foaming a plurality of urethane foams having different hardnesses.

<Prior Art> In recent years, cushion bodies in which foams of different hardness are laminated have been used as cushioning materials for vehicle seats such as automobiles in order to improve the ability to hold and hold the body of a seated person. Figure 3 shows such a cushion body 1.
The central part 11, where the back or wide part of the seated person is located, is made of urethane foam with low hardness and has good sealing properties. The raised left and right parts 12, 12 are made of urethane foam with high hardness to improve the ability to hold the seated person's body. Conventionally, cushion bodies made by laminating foams with different hardnesses are manufactured by foaming foaming solutions with different hardnesses in a mold, but in order to improve the bondability of the interface between the foams, 1) Placing a thin film on the interface between foams with different hardness,
-144761 Publication) or (2) Paper, cloth, net, etc. with many holes were placed on the boundary surface (Japanese Patent Application Laid-Open No. 50-144762, USP 3,257゜14).
9).

However, in the method (1) above, the thin film obstructs air permeability, making it impossible to obtain good cushioning properties, and the thin film is expensive, making the cushion body expensive. or,
In method (2), stock solutions with different hardnesses mixed with each other, making it impossible to produce a stable product, making it impossible to obtain a cushion body with the desired characteristics.

In order to solve the above-mentioned drawbacks, the applicant previously filed Japanese Patent Application No. 1983-76189. This invention is a method in which one or more partition plates are inserted into a mold, different foaming stock solutions are injected into the mold using the partition plates as boundaries, and then the partition plates are pulled out into the mold in accordance with the foaming speed. This eliminates the need to dispose a thin film or porous fabric on the boundary surface, and prevents the foams from mixing with each other.

<Problems to be Solved by the Invention> However, in the above-mentioned prior invention, when the reaction rates of the foaming stock solutions differ, it is not possible to pull out the partition plate in accordance with the foaming speed, which limits the formulation of the foaming stock solution that can be used. It was happening. In addition, after the partition plate is pulled out, the foam may flow out of the mold from the part where the partition plate is pulled out, making it impossible to obtain a cushion body with a good shape.Furthermore, the temperature of the foaming stock solution and the mold temperature may not be the same. Because of this, it is difficult to maintain the same foaming speed, and there is a problem in that mass production is poor.

The object of the present invention is to solve the problems of the prior invention method of laminating foams of different hardness or obtaining a cyan body by pulling out a partition plate inserted into a mold.

Means for Solving the Problems> For this reason, the present invention provides a method for quickly pulling out the partition plate inserted into the mold before the reaction of each foaming stock solution is completed, and closing the opening of the mold after the partition plate is pulled out. And then,
It is characterized by reaction-curing each foaming stock solution.

<Example> The present invention will be explained in more detail below.

FIGS. 1(a) to 1(b) are sectional views showing an embodiment of the process of the present invention, and show a mold 1 for forming a cushion body of a vehicle seat. This mold 1 has a cavity formed inside thereof for forming a sheet as shown in FIG. First, as shown in FIG. 1(A), two partition plates 2 are inserted into a mold 1. In this embodiment, the partition plate 2 is inserted at the boundary between the center and left and right parts of the sheet, and divides the inside of the mold 1 into a central foaming chamber 3 and left and right foaming chambers 4. Next, foaming chambers 3 and 4 (different foaming stock solutions A) are separated as shown in FIG.
and B are injected, the lid 5 is placed from above to seal the inside of the mold, and the re-foaming stock solution is simultaneously (foamed). In this case,
A foaming stock solution A formulated to form a foam with low hardness is injected into the central foaming chamber 3, and a foaming stock solution B formulated to form a foam with high hardness is injected into the left and right foaming chambers 4. Ru. Further, an opening portion 6 having a width approximately equal to the thickness of the partition plate 2 is formed in the lid 5 so that the upper end of the partition plate 2 is exposed to the outer surface of the lid 5. In addition, when the reaction rates of the foaming stock solutions are different, it is preferable to provide a time difference such that the foaming stock solution with a low reaction rate is injected, and then, after a predetermined period of time, the foaming stock solution with a high reaction rate is injected.

Each of the foaming stock solutions injected as described above reacts in each of the foaming chambers 3 and 4 and foaming is performed, but before this reaction is completed and hardening, the partition plate 2 will be extracted. This drawing occurs rapidly, and the foams forming in the mold do not mix with each other.
Each stock solution is foamed with its own characteristics, and the characteristics of each foam are realized as they are. After pulling out the partition plate 2, as shown in the same figure (d), a clamp 7 is attached to the upper surface of the opening part 6 of the lid through which the partition plate 2 was inserted to close the opening part 6 to prevent the foam from flowing out, and the mold is then The foaming stock solution is reacted and hardened in 1. In this case, the mold 1 may be heated to accelerate curing.

Through this curing, a seat-shaped cushion body is formed,
Next, the mold 1 is opened and the cushion body is taken out.

FIG. 2 is a plan view of the sheet-shaped cushion body 10 formed as described above, and FIG. 3 is a cross-sectional view taken along the line ■-■. In addition to providing cushioning properties, the left and right portions 1
2. The foam has a high hardness and is foamed to enhance the ability to hold the seated person's body.

In the present invention, the number of partition plates is not limited and can be increased or decreased. For example, the center of the sheet may be further divided to form a more European form on the front of the center of the seat. This makes it possible to reduce the fatigue level of pedal operations such as the clutch pedal, accelerator pedal, and brake pedal.

Example 1 Foaming ingredients 't& A and B as shown in Table 1 were formulated, a partition plate 2 was inserted into the mold 1, and the foaming stock solution B was placed in the foaming chamber 3 and the foaming stock solution A was placed in the foaming chamber 4. After injection, the mold was sealed with a lid 5. Next, before each stock solution has sufficiently hardened, that is, 40 to 60 seconds after the start of the reaction, the partition plate 2 is rapidly pulled out, and immediately after the partition plate 2 is pulled out, a clamp 7 is attached to the opening.
was installed and the opening was sealed. After curing, the molded product was demolded to obtain a sheet-shaped cushion body 10.

(Leaving space below) Table 1 Example 2 After injecting the foaming stock solution B formulated as shown in Table 1 above into the foaming chamber 4, the foaming stock solution A was injected into the foaming chamber 3 after a predetermined time. A sheet-shaped cushion body was obtained by foaming in the same manner as in 1.

<Effects of the Invention> According to the present invention described above, a cushion body in which foams having different hardnesses are laminated can be obtained by one foaming process,
In addition to being able to reduce the number of steps and not using a thin film, it is possible to obtain a molded product with good air permeability and pliability, as well as the following effects.

(1) Since the partition plate is rapidly pulled out before the reaction of the foaming stock solution is completed, there is no mixing of each foam, and the characteristics of each foam can be realized as they are.

(2) Since the opening of the lid is closed after the partition plate is pulled out, the foam does not flow out to the outside, and a cushion body with a good shape can be obtained.

[Brief explanation of the drawing]

FIGS. 1(a) to 2) are sectional views showing the process order of the present invention, and FIGS. 2 and 3 are a plan view and a sectional view taken along line I-II of an example of a cushion body. 1... Mold, 2... Partition plate, 3, 4... Foaming chamber, 5... Lid, 6... Opening part, 7... Clamp,
10... 992 shoes, A, B... Foaming concentrate patent applicant NHK Spring Co., Ltd. Agent Patent attorney Hideo Sato Patent attorney Hideo Ohashi / (I) (Han, f21ffi lθ tri) d) Bone 3♂

Claims (2)

[Claims] (1) Insert one or more partition plates into the mold to divide the mold into two or more foaming chambers, inject foaming solutions that form foams with different hardness into each foaming chamber, and seal them to separate each solution. production of a cushion body characterized by reacting, rapidly pulling out the partition plate into the mold before the reaction is completed, closing the opening of the mold from which the partition plate has been pulled out, and then reacting and curing each foaming stock solution. Method. (2) The method for manufacturing a cushion body according to claim (1), characterized in that the foaming stock solution is injected at different times.