JPS6046230A - Preparation of composite foamed body - Google Patents

Abstract

PURPOSE:To obtaina natural composite body without fitting process and adhesion process by arranging containers with perforated holes in the mold cavity formed by a core mold and a cavity mold, supplying expandable resin beads between the core mold and the container through the perforated holes and pressure-molding it. CONSTITUTION:A container provided previously with perforated holes is arranged on the side of the cavity mold in the mold cavity formed by a core mold and a cavity mold. Then, expandable resin beads are supplied fully between the core mold and the container through the perforated holes, heated, molded to form a composite foamed body having a foam inside the container. That is, a polypropylene molded piece 3 with perforated holes 4 are arranged in the mold cavity provided between the cavity mold 1 and the core mold 2. Then, feeders 5 are stuck tightly to the respective perforated holes 4, the space part provided between the core mold 2 and the polypropylene foam 3 is filled with expandable polystyrene beads through the perforated holes 4 and then the beads are heated by steam, molded to obtain an integral molding incorporated by the polypropylene molded piece 3 and a polystyrene foamed piece 6.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for producing a composite foam molded article, and more specifically, to a composite foam molded article that allows a foam molded article to be molded inside a container, and also enables physical integration of the two. This relates to a manufacturing method.

BACKGROUND ART Conventionally, an integrally molded product of a box made of an injection molded product of ABS resin or the like and foamed borisdyrene as a heat insulating material on the outside of the box is well known. However, when it comes to containers such as drain pans, for example, even if an attempt is made to integrally mold a drain pan with a structure in which a foamed polystyrene molded body is integrated inside an injection molded body of ABS resin, filling with foamed polystyrene beads is difficult. This is extremely difficult, and the initial objective cannot be achieved when the compatibility is poor, such as between an injection molded product of polyolefin such as polypropylene and a foamed polystyrene molded product. In this way, the actual situation is to make the injection molded product and the foamed borisdirene molded product separately, and either fit the latter inside the former, or in the case of thin walls, vacuum form an extruded sheet and combine it with an adhesive. . However, with the method of simply fitting, there are problems in that it is difficult to form a contact shape with the injection product, resulting in insufficient integration, requiring a lot of man-hours for fitting, and requiring inventory clearance.On the other hand, methods using adhesives The process becomes complicated, the cost of the vacuum-formed product increases, and if there is a gap between the injection molded product and the foamed polystyrene molded product, they cannot be bonded, so there is a problem that considerable molding precision is required.

In view of the above circumstances, the present inventor has completed the present invention as a result of intensive studies to overcome the above-mentioned problems.

That is, the first aspect of the present invention is that when manufacturing a composite foamed molded product in which a foamed molded product is installed inside a container, the molded material is removed near the cavity mold side in the mold cavity formed by the core mold and the cavity mold. Composite foaming characterized in that a container having at least one through hole bored in advance is placed in the core mold, and then foamable resin beads are filled between the core mold and the container through the through hole and heated and molded. The second aspect of the present invention is a method for producing a molded body, and the second aspect of the present invention is when manufacturing a composite foam molded body in which a foam molded body is placed inside a container having an opening such as a drain pipe,
A container with at least one through hole drilled in advance is arranged near the cavity mold side in the mold cavity formed by the core mold and the cavity mold, and a rod-shaped container that reaches the surface of the core mold is placed inside the opening. A metal fitting is inserted, the opening of the mold for inserting and removing the opening is closed with a plate metal fitting, and then foamed resin beads are filled through the through hole between the core mold and the container, and heated and molded. The content is a method for manufacturing a composite foam molded article characterized by the following.

An explanation will be given based on the drawings showing the embodiments of the present invention. In FIG. 1, a polypropylene molded body (3
) is placed closer to the cavity mold (1) side. The polypropylene molded body (3) has at least one through hole (
4) is perforated. The through holes (4) not only serve as filling holes for the foamable resin beads, but also become clogged with the foamed molded body after molding and are physically integrated with the polypropylene molded body due to the so-called anchor effect. ,
An appropriate number of holes are drilled to ensure the full effect.

Next, the feeder (5) is brought into close contact with the through hole (4), and the expandable polystyrene beads are inserted into the core mold (2) and the polypropylene molded body (3) as expandable resin beads through the through hole (4). After filling the space formed between
Heat molding is performed using steam to obtain an integral molded body of a polypropylene molded body (3) and a polystyrene foam molded body (6).

In this case, by heating the polypropylene molded body (3) by one-sided heating before double-sided heating, the surface of the polystyrene foam molded body on the side that comes into contact with the polypropylene molded body can be molded smoothly. It is also desirable to increase the number of slots in the core mold as much as possible, and if filling defects still occur, provide small holes. Additionally, parts of the polypropylene molded body that are not in contact with the foamed molded body may become deformed due to overheating, but this can be prevented by providing an overheating preventer on the surface of the core mold and/or cavity mold that comes into contact with the polypropylene molded body. This can be prevented by

The overheating preventer may be made of any material as long as it is as thin as possible and can withstand the molding temperature, such as cloth, heat-resistant film, etc.

In the manufacturing method of the present invention, the polystyrene foam molded body bites into the through hole of the polypropylene molded body, and the two are physically integrated by the so-called anchor effect. However, if the two are to be more strongly integrated into a composite body, an adhesive may be applied to the surface of the polypropylene molded product that comes into contact with the polystyrene foam molded product. A thermoplastic adhesive is suitable as the adhesive.

FIGS. 2 and 3 illustrate a method of manufacturing a composite foam molding for a container having an opening such as a protruding drain pipe, such as the drain pan shown in FIG. 4. FIG.

In the figure, after inserting an opening (7) such as a drain pipe provided in the polypropylene molded body (3) through the mold opening of the cavity mold (1), the core mold (2) is set. . Next, a bar of gold is placed inside the opening (7). Insert (8). The rod-shaped metal fitting (8) is inserted so as to reach and come into close contact with the surface of the core mold (2). Next, with the mold opening closed with a metal plate (9), expandable polystyrene beads are filled and heated to form the mold. In this example, the rod-shaped metal fitting (8) and the plate-shaped metal fitting (9) are integrally connected and configured to be driven by one air cylinder (10).

The plate-shaped metal fittings prevent the polypropylene molded body from deforming during heat molding.

Since the present invention is a method of integrally molding a foam molded container inside a container, the containers used in the present invention are not limited to plastic molded products such as ABS resin, polyethylene, and polypropylene, but are also made of metal, ceramic, etc. Containers such as the above are also suitably employed. Examples of foamed resin beads include polyethylene beads, polypropylene beads, etc. in addition to polystyrene beads. Furthermore, by using colored beads of the same color as the container, the container and the foamed molded product inserted into the through-hole of the container have the same color, making it possible to eliminate unnaturalness.

As mentioned above, the present invention (1) allows the foamed molded body to be integrally molded inside the container, eliminating the need for fitting or gluing processes as in the past; (2) as a filling hole for foamed resin beads; (3) By using colored beads of the same color as the container, a natural composite can be obtained (4) It has many advantages such as no need for storage space for foam moldings,
Its practicality is extremely great.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing an embodiment of the present invention, FIGS. 2 and 3 are plan and side cross-sectional views showing other embodiments of the present invention, and FIG. 4 is an example of a drain pan. FIG. 1 Cavity mold 2 Core mold 3 Polypropylene molded body 4 Through hole 5 Feeder 6 Polystyrene foam molded body 7 Opening of drain pipe, etc. 8... Rod-shaped metal fitting 9... Plate-shaped metal fitting 10... Air cylinder patent applicant Kaneji Kagaku Kogyo Co., Ltd. agent Patent attorney Kenji Itami (10 completed)

Claims (1)

[Scope of Claims] When manufacturing a composite foam molded product in which a foamed molded product is placed inside a container, a mold cavity near the cavity mold side in a mold cavity formed by a core mold and a cavity mold. Composite foaming characterized in that a container having at least one through hole bored in advance is placed in the core mold, and then foamable resin beads are filled between the core mold and the container through the through hole and heated and molded. Method for manufacturing molded bodies. 2. Core mold and/or parts of the container that do not come into contact with the foam molded product.
Alternatively, the manufacturing method according to claim 1, wherein an overheating preventer is provided on the surface of the cavity mold. 3. The manufacturing method according to claim 1 or 2, wherein an adhesive is applied to the contact surface of the container with the foamed molded product. 4. When manufacturing a composite foam molded product in which a foamed molded product is placed inside a container equipped with an opening such as a drain pipe, a cavity mold in a mold cavity formed by a core mold and a cavity mold is used. A container with at least one through hole drilled in advance near the mold side is placed, a rod-shaped metal fitting that reaches the surface of the core mold is inserted into the opening, and a plate is inserted into the mold opening for inserting and removing the opening. 1. A method for producing a composite foam molded article, which comprises closing the core mold with a shaped metal fitting, then filling the gap between the core mold and the container with foamable resin beads through the through hole, and heat-molding the core mold. 5. Core mold and/or parts of the container not in contact with the foam molded product
Alternatively, the manufacturing method according to claim 4, wherein an overheating preventer is provided on the surface of the cavity mold. 6. The manufacturing method according to claim 4 or 5, wherein an adhesive is applied to the contact surface of the container with the foamed molded product. 7. The manufacturing method according to claim 4, 5, or 6, wherein the rod-shaped metal fitting and the plate-shaped metal fitting are integrally connected and driven by one air cylinder.