JP2740935B2 - Foam molding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to] is related to installation pad, door trim, etc., foamed molding how to foam molding an integral foam made foamed product skin and foam molding raw material.

[0002]

2. Description of the Related Art In general, a foamed product in which a skin such as an instrument pad and a door trim is integrally foamed with a polyurethane foam is provided with a foaming mold, the polyurethane foam material is injected, foamed, solidified, and then demolded. In order to dispose the skin on the lower mold of the foaming mold, conventionally, as shown in FIG. 3, the skin 1 is inserted into the lower mold 2 of the foaming mold, and the outer skin is arranged along the shape of the foaming mold. After that, the protrusions 10 on the periphery of the lower mold 2 are fitted into the recesses 11 formed in the outer skin 1 for accurate positioning.
Is operated by operating the vacuum suction device P ₁ installed in the lower mold 2, suctioning through the lower mold suction holes 3, and piping 4, 5 to completely fix the epidermis 1 to the foam mold lower mold 2. It is known that the shape of the concave and convex portions is a hollow prismatic shape in addition to a cylindrical portion. (See Japanese Utility Model Publication No. 3-334)

[0003]

However, in the fixing of the skin by the above method, a large number of recesses for fixing to the foaming lower mold must be formed in advance at the skin end, so that after the skin is formed, the skin is removed from the skin forming mold. During molding, the demolding work becomes complicated and requires a long working time. At the time of demolding, the skin is stretched, and the skin is deformed and distorted, resulting in a decrease in the skin yield and wrinkles and deformation defects during foam molding. Have problems.

[0004] Further, when the product is demolded after foam molding,
It is necessary to peel off the concave part arranged in the skin terminal from the convex part of the foam lower mold, and it takes longer to remove the mold. In addition, when the skin terminal and the foam mold parting surface are fixed with tape, extra costs are further increased. Will be. And the above is the fixing recess
And fixed as described in JP-A-4-107110.
The same is true when forming the projecting portion.

SUMMARY OF THE INVENTION The present invention addresses the above-mentioned situation, and aims at simplifying and improving the workability of removing the mold from the molding of the skin by finding the installation of a piping for absorbing the skin. It is an object of the present invention to eliminate the work of correcting distortion, to reduce wrinkles and deformation defects of the skin during foam molding, and to improve the demolding workability after foam molding.

[0006]

Means for Solving the Problems That is, the present invention without providing a fixing for irregularities in the foam molding mold in Table skin end portion as a means for achieving the above object, the epidermis was left flat it assumes to be used, therefore a recess in the lower mold perimeter edge of the foam molding mold, using a foaming mold with no as allowed to couple the skin suction pipe connected to a vacuum suction device the recess, the terminal portion After inserting the flat skin having no irregularities for fixing to the foaming mold into the lower mold of the mold, and arranging the terminal portion to remain flat at the peripheral edge of the lower mold, vacuum By operating the suction device, the skin end is suction-fixed to the peripheral edge of the lower die through a suction pipe connected to the recess at the peripheral edge of the lower die, and then the vacuum suction device is again activated to operate the entire epidermis. Is fixed to the inner surface of the lower mold, and then the foam molding raw material is Type provides foam molding method in which foam molding.

The vacuum suction device for suctioning the terminal portion of the epidermis and the vacuum suction device for suctioning the entire epidermis along the inner surface of the lower mold may be provided separately or may be shared.

[0008]

According to the present invention, the skin is used in the form of a flat surface having no irregularities for fixing the foaming mold at the end thereof .
Irare, thus demolding operations and after skin layer forming, stretching of skin that occurs during demolding, with modifying the strain does not need, during foam molding, stretched epidermis, Ya wrinkles of the skin due to strain Deformation defects are reduced, and work quality of foam molding is improved and product quality is improved.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a main part of a foaming mold and a foaming molding method used in the method of the present invention. In the drawing, reference numeral 1 denotes a known skin mold, a skin molded by a molding apparatus, and 2 denotes a lower part of the foam mold. type, 3 divided surfaces of the lower mold, i.e. the suction hole provided in the epidermis沿設surface, 4 and 5 are connected to a vacuum suction device P ₁ for sucking securing the skin 1 to the foaming mold lower mold 2 The outer skin 1 is inserted into the lower mold 2 of the foaming mold, is sucked through the suction holes 3 through the respective pipes 4 and 5 by the vacuum suction device, and is attached to the inner surface of the lower mold 2. Is fixed by suction as in the conventional method shown in FIG.

[0011] However, in the present invention does not have a recess 11 as shown in FIG. 3 in the epidermis 1 has the terminal portion 1a as shown in FIG. 1, stuck in the plane.

On the other hand, the lower die 2 is not provided with a projection as shown in FIG . However, the lower die 2 is provided with a concave portion 6 at the peripheral edge, and the vacuum suction devices P ₁ , P ₂ have valves V ₁ ,
Suction pipes 4 and 7 are connected via a V ₂ is connected.

Although the shape of the concave portion 6 is a long hole groove shape in the figure, it may be a round hole groove shape. In short, it is sufficient if the skin 1 can be brought into close contact with the suction.

Here, the concave portion 6 at the peripheral edge of the lower die 2 is not necessarily one, but it is needless to say that an appropriate number of concave portions 6 are provided.

In FIG. 1, the suction pipe of the left concave portion 6 is relayed to the suction pipe 4 from the suction hole 3 of the lower die 2 in FIG. As described above, the vacuum suction devices are respectively different devices P ₂ and P ₃ , the branch pipes of the suction pipes connected to the plurality of recesses 6 at the peripheral edge are united to form pipes 7 and 8, and the valves V _{2 and} V _{3 are respectively provided.} , V ₃ may be connected to the vacuum suction devices P ₂ , P ₃ .

Next, a molding method using the above foaming mold will be described.

First, a skin 1 molded by a skin molding die as is known is inserted into a lower mold 2 of a foam molding die, switches on the vacuum suction devices P ₂ and P ₃ are turned on, and a skin end portion 1a is arranged at a peripheral edge. Then, it is set in the lower mold 2 of the foaming mold.

[0018] The entire epidermis putting switch vacuum suction device P ₁ then placed along the inner surface of the lower mold 2 sucks set.

Thereafter, a foaming material, for example, a polyurethane material, which is a foaming material, is injected into the skin 1 in a foaming mold by a known method, and foamed.
It can be demolded and taken out as a foam product by integral molding of a predetermined shape.

In the above molding, the vacuum suction is usually 20
0 mmHg (266666.4 pa) or more is desirable.

Thus, the integral foam molding can be carried out while ensuring the positioning of the skin to the mold without the need to provide the conventionally provided recesses or projections of the skin and the projections or recesses of the foaming mold. .

[0022]

As described above, the present invention does not provide irregularities for fixing to the foaming mold at the skin end portion, and keeps the surface of the foaming mold at the peripheral edge of the foaming mold for suctioning the skin. the concave portion is provided, with suction through concatenated suction pipe therein, and characterized in that to fix, during the skin layer forming for forming is carried out without providing the anchoring irregularities to particular mold in the epidermis, de No mold work is required, so not only the skin is easily formed and the workability is improved, but also the stretching and distortion that occur when the skin is removed from the mold are remarkably reduced, and a processing (annealing) work for correcting this is unnecessary. .

Further, it is possible to avoid poor foaming at the time of foam molding due to stretching and distortion occurring during skin molding, thereby improving product yield.

Further, since there is no need to perform positioning by fitting the concave and convex to the foaming mold, the workability of the skin set to the foaming mold is improved, and the workability of removing the foaming mold is improved. There is also an advantage that the adjustment of the alignment between the skin and the foaming mold can be reduced, and a remarkable effect can be expected on the rationalization of the operation in the foaming molding, together with the necessity of the annealing equipment and jigs, which have been conventionally required.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a foam molding method together with a main part of a foam mold used in the present invention.

FIG. 2 is a partial plan view of FIG.

FIG. 3 is a schematic sectional view showing a conventional foam molding die and a foam molding method.

[Explanation of symbols]

1 epidermis 1a skin terminal unit 2 foaming mold lower mold 3 the suction holes 4, 5, 7, 8 suction pipe 6 recesses P _{1, P} 2, _{P 3} vacuum suction device

Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29K 105: 20 B29L 31:58

Claims (1)

(57) [Claims] 1. A foaming mold in which a concave portion is formed at a peripheral edge of a lower mold, and a skin suction pipe connected to a vacuum suction device is connected to the concave portion, and irregularities for fixing to a molding die are formed at a terminal portion. After inserting the flat skin that does not have a flat shape into the lower mold of the foaming mold and disposing the flat end portion at the peripheral edge of the lower mold while keeping the flat shape, the vacuum suction device is operated, sucking the skin end portion through linked suction pipe into the recess of the lower mold perimeter edge on the lower mold perimeter edge, secured by fixing, then operating the vacuum suction device again the whole epidermis in the lower mold interior surface is allowed, then injected foamed molded material, foam molding method characterized by allowed to foam molding.