JPH01195007A - Manufacture of integral foaming article - Google Patents

Abstract

PURPOSE:To obtain the integral foaming article such as an automobile instrument safety panel or the like in an excellent productivity and low cost by providing a heating element at the die placement being suited to the edge parts of a core and facing and also employing a heat depositive core and/or facing, and sealing the core and facing edge parts such that they are heated while being held forcedly. CONSTITUTION:The core 4 is arranged in fitting the outer periphery to the cavity 2A of the upper die 2 of a die 1 and the facing 5 is also arranged in fitting the outer periphery to the cavity surface 3B of the lower die 3. Next, the foaming resin material such as urethane solution or the like is injected into the inside of the facing 5 and the foaming mold is performed in closing the upper and lower dies 2, 3 and also the facing 5 is pressed to the core 4 by cylinders 9, 9' on the heating surface 6h, 6'h' of the heating elements 6, 6' so as to be heated by a heat source. Here, the core 5 is made up of a heat depositive material and the foaming mold 10 is formed with the core 4 and facing 5 integrally and also the facing 5 is melted for sealing the core 4 in heat deposition through the heat from the heating surfaces 6h, 6'h' of the heating elements 6, 6' in the cavity surface positions 3b, 3b'.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for manufacturing an integrally foamed molded product in which a foam is integrally molded between a core material and a skin of an automobile instrument safety panel or the like.

(Conventional technology) Conventionally, automobile instrument safety panels, etc. have a core material and a skin of a predetermined shape arranged in an upper and lower arrangement, and a foamable resin material such as undiluted urethane is injected between the core material and the skin. It is manufactured by integrally molding a foam such as urethane foam.

In addition, the sealing of the integrally foamed molded product at this time, that is, the sealing of the ends of the core material and the outer skin, is performed, for example, as shown in FIG. [Slab method for inserting the slab 11, for example, as shown in FIG. A nesting method in which a nesting member 12 is inserted into the
This is done by a film bonding method in which a film is adhered to the outer circumferential surface of the core material and/or the outer skin at the edge where the core material and the outer skin are arranged in an upper and lower mold, and the outer periphery of this edge is sealed with the film. . Recently, instrument panels (integral foam molded products) that use a frame made of foamed resin bonded in advance to either the inner skin (core material) or the outer skin along the inside direction of the mold starting from the above-mentioned end have been developed. The manufacturing method is conventional (Japanese Patent Laid-Open No. 61-95909).

(Problems to be Solved by the Invention) However, sealing by the slab method requires manual attachment of the slab to the core material or outer skin, which causes variations in the attachment position of the slab. The cause is that during molding, the flow of the foamable resin material such as the urethane stock solution changes, resulting in defects such as voids and cell roughness. In addition, in the case of the nesting method, if there is a defect in the insert, a seal failure will occur, and if the insert is lowered into the mold when closing the mold, the mold will be damaged.

In either case, the problem arises that a good molded product cannot be obtained, but in order to perform υ molding in which the insert is inserted into the mold to prevent the insert from being damaged or falling into the mold, Folds with great care, is not easy, and has poor workability. In the case of the film adhesion method, there is a problem that the film is easily damaged during adhesion or molding, and the above three methods require auxiliary agents such as slabs and adhesive films for the molded product. They have a common disadvantage of high cost, such as the need to provide a core material that matches the shape of the child.

On the other hand, if a frame body made of foamed resin is bonded in advance to either the core material or the skin as described above, defects such as voids and rough cells can be prevented, but The problem is that a core material or a skin material to which the frame body is bonded is required, and the manufacturing thereof requires manpower and time, resulting in an increase in the cost of the product.

The present invention has been made in view of the above circumstances, and it is possible to prevent defects such as voids and rough cells from occurring manually as in the above-mentioned slab method, and to create a frame using the nesting method or the foamed resin. To easily and quickly provide an integrally foamed molded product such as an automobile instrument safety panel, etc., without causing flakes at the edges of the core material and skin, as in the case of using a core material or skin bonded together. The purpose is to

(Means for Solving the Problems) In order to achieve the above object, the method for producing an integrally foamed molded product of the present invention includes arranging a core material and a skin between upper and lower molds, and placing a foam between the core material and the skin. When producing an integrally foamed molded product, a heating element is provided in the mold portion corresponding to the ends of the core and skin, and a core material and/or skin that is heat bathable is used. It is characterized by sealing by heating the epidermal end while compressing it.

The mold used in the method of the present invention usually has an outer circumferential surface of the core material on one side of the upper and lower molds, and a cavity surface that fits with the outer circumferential surface of the skin on the other, but the shape of the core material and the skin, Depending on the material, auxiliary members may be interposed between the upper and lower molds, the core material, and the outer skin.

In the heating element, the heating surface is usually arranged at the end of the core material and the skin which require sealing, and the element body is embedded in the upper mold or the lower mold. Note that it is possible to use one or more heating elements depending on the shape of the ends of the core material and skin that require sealing, the size of the heating element, the heat capacity, etc. It is also possible to provide both the upper and lower molds with the heat generating surfaces facing each other.

In addition, clamping pressure when producing an integrally foamed molded product is achieved by using the mold pressure of the upper and lower molds after the mold is closed, or by pressing a heating element against the core material or the skin.

(Function) In the present invention, by pinching the ends of the core material and the skin, leakage of the foamable resin material from the ends is prevented.

Further, by heating the heating element to a temperature higher than the melting temperature of the heat-fusible core material and/or skin, the core material and skin at the ends are bath-bonded. Furthermore, this bath-bonded end is simultaneously crimped by a clamping force and thus sealed.

Here, if a thermosetting liquid resin such as urethane stock solution is used as the foamable resin material, the resin near the end position to be sealed will be thermoset, so the sealing layer will reliably foam. The resin material is prevented from leaking from between the core material and the skin at the sealed end.

(Example) EXAMPLES The present invention will be specifically explained below with reference to Examples.

FIG. 1 is a sectional view showing an example of two molds according to the present invention, and this mold 1 is composed of an upper mold 2 and a lower mold 3. As shown in FIG.

The upper mold 2 has two cavity surfaces that fit with the outer peripheral surface of the core material 4, and the lower mold 3 has a cavity surface 3B that fits with the outer peripheral surface of the skin 5. . Furthermore, heating surfaces 6h, 6'h' are provided at the cavity surface positions 3b, 31/ of the lower mold 3 corresponding to the ends of the core material 4 and the outer skin 5 that require sealing.
Heating elements 6, 6' are embedded in the lower mold 3 by arranging the heating elements 6, 6'. The heating elements 6, 6' are connected to cylinders 9, 9', as shown in FIG.
The cylinders 9 and 9' can be moved forward and backward within the lower mold 3 from the cavity surface positions 3b and 3b'. Historically, the heating cables 6, 6' are both connected to a heat source 7, not shown.

Using this mold 1, an integrally foamed molded product 8 can be manufactured in the following manner.

That is, first, the core material 4 is placed with its outer circumference aligned with the two cavity surfaces of the upper die 2 of the mold 1, and the skin 5 is placed with its outer circumference aligned with the cavity surface 3B of the lower die 3. A foamable resin material such as urethane stock solution is injected into the inside, and the upper and lower molds 2 and 3 are closed to perform foam molding, and the cylinders 9 and 9'
The skin 5 is pressed against the core material 4 by the heating surfaces 6h, 6'h' of the heating elements 6.6' and heated by the heat source 7. Here, the skin 5 is made of a heat-weldable material, and by foam molding, a foam molded body 10 is formed integrally with the core material 4 and the skin 5, and the cavity surface position of the lower mold 3 is 3b, 3b
' The heating surfaces 6h, 6' of the heating element 6゜6'
The outer skin 5 is bath-melted by the heat generated from h' and thermally welded to the core material 4, and sealing is performed at this portion. At the same time, if a thermosetting liquid resin such as urethane stock solution is used as the foamable resin material, the cavity surface of the lower mold 3 in the cavity & 3b, 3b' (near the same resin at P, P') Since it is thermally cured, the extrusion of the foamable resin material from the integrally foamed molded product is reliably prevented from occurring in the sealing layer, and the sealing layer becomes reliable and strong.

In addition, foam molding itself uses a foamable resin material mixed with a foaming agent or foaming agent as appropriate, and if necessary, this foamable resin material can be pre-foamed. Needless to say, various methods can be selected depending on the type of molded product and the purpose and use of the integrally foamed molded product to be manufactured.

(Effects of the Invention) As explained above, according to the method of the present invention, the edges of the core material and the skin are reliably sealed without leakage of the foamable resin material, resulting in molding defects such as voids and rough cells. can be eliminated. In addition, there is no need to use extra material to assist in sealing each molded product, as is the case with the slab method, nesting method, film bonding method, etc., and it is possible to quickly and easily produce integrally foamed molded products. Can be done.

Therefore, it is possible to provide high-quality integrally foamed products such as automobile instrument safety pipes and the like with good manufacturability and at low cost.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an example of a mold according to the present invention, Fig. 2 is an enlarged sectional view of the heating element portion of Fig. 1, and Fig. 3 is a sectional view of a mold for explaining the slab method. Cross-sectional view showing an example FIG. 4 is a cross-sectional view showing an example of a mold used in the nesting method. 1... Mold 2... Upper mold 3...
...Bottom mold 4...Core material 5...
・Skin 6.6'...Heating element 8...Integrated foam molded product 9...Foam molded product patent applicant Toyota Motor Corporation representative Patent attorney Yumi Kaly 2 people C10) Figure 1: Figure 3: Figure 3:

Claims (1)

[Claims] 1) When producing an integral foam molded product by arranging the core material and the skin between the upper and lower molds and forming a foam between the core material and the skin, the mold parts corresponding to the ends of the core material and the skin A method for manufacturing an integrally foamed molded article, which comprises providing a heating element on the body, using a heat-fusible core material and/or skin, and sealing the ends of the core material and skin by heating while pinching them. .