JPH06106562A - Manufacture of insert molded product - Google Patents

Abstract

PURPOSE:To manufacture at a low cost an insert molded product which is in an arbitrary form and nice. CONSTITUTION:This is a manufacture of an insert molded product 7 wherein simultaneously with formation of the solid molded product 6, an insert sheet 1 is formed on its surface by fitting the insert sheet 1 which is obtained by forming at least a pattern layer and adhesive layer on a base sheet to an injection mold 4 comprised of a female mild 41 possessing a recessed part 40 for melding of the desirous solid molded product and a male mold 42, and after mold clamping, molding resin 5 is injected between the molds. Then prior to fitting of the insert sheet 1 between the female mold 41 and male mold 42, the insert sheet 1 is preformed so that the insert sheet 1 coincides with a form of the inside of the recessed part 40 of the female mold 41 of the same is trimmed so that the same is not forced out from the fringe 60 of the surface of the desirous molded product 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing insert-molded products used for front panels and buttons of AV equipment, instrument panels of automobiles and the like.

[0002]

2. Description of the Related Art Conventionally, as a method for producing an insert-molded article, there is one described in JP-A-57-102328. This method prepares a molding die composed of a male mold having a convex portion and a female mold having a concave portion that fits in the convex portion, and a sheet-shaped component drawn by resin, aluminum or the like. After mounting the sheet-shaped part in the concave part of the female mold and closing the mold, the peripheral part of the male convex part and the peripheral part of the female concave part are crossed to cut unnecessary parts of the sheet-shaped part, and after the mold closing is completed. A method of injecting a resin material and integrally molding the resin material and the sheet-shaped component.

[0003]

However, in the conventional manufacturing method, since the sheet-like material is cut by the molding die, there are the following problems. 1. The clearance between the peripheral edge of the male convex portion and the peripheral edge of the female concave portion is required to have an accuracy of several μm in order to cleanly and accurately cut the sheet-shaped component. However, the temperature of the male die having the sprue for injecting the resin material is higher, but the temperature of the female die having no sprue is lower than that of the male die. Due to this temperature difference, a slight deviation occurs in the expansion coefficient of each mold, and the clearance cannot always be kept constant. Therefore, when the clearance is small, the peripheral edges of the molding dies collide with each other and are damaged, resulting in spilling of the blade. Further, when the clearance is large, there is a portion that is not cut at the peripheral edge of the sheet-shaped component. Further, unnecessary cutting dust is generated and adheres to the resin material injected from the sprue.

2. The peripheral edge of the molding die must be angled so as to function as a blade. For this reason,
It becomes a special injection molding die and costs much.

3. In order to fix the edge of the sheet-shaped component to the injection molding die when cutting the sheet-shaped component, the components such as the fixing plate and the springs and pins attached thereto must be incorporated. I have to. Therefore, the structure of the injection molding die becomes complicated, and the shape of the insert-molded product obtained is restricted.

An object of the present invention is to solve the above problems, and an insert-molded article having an arbitrary shape is manufactured by using an insert sheet in which unnecessary portions are cut cleanly and an injection-molding die which is inexpensive. Is intended to be manufactured.

[0007]

In order to achieve the above object, the method for producing an insert-molded article of the present invention requires an insert sheet in which at least a pattern layer and an adhesive layer are formed on a base sheet. When a three-dimensional molded article is formed by mounting the three-dimensional molded article on an injection molding die consisting of a female mold and a male mold having a recess for molding the three-dimensional molded article, and after injecting a molding resin between the molds. At the same time, in a method for manufacturing an insert-molded product in which an insert sheet is formed on the surface thereof, before the insert sheet is mounted between the female die and the male die, the insert sheet is made to match the inner surface shape of the concave portion of the female die. Was preformed and trimmed so as not to protrude from the peripheral edge of the surface of the desired three-dimensional molded article.

In the method of manufacturing an insert-molded product according to the present invention, the preform and trimming of the insert sheet may be performed at the same time by using a preform die having a cutting blade.

The present invention will be described in detail below with reference to the drawings. First, the insert sheet 1 is preformed so as to match the surface shape of a desired three-dimensional molded product, and trimmed so as not to protrude from the peripheral edge of the surface of the desired three-dimensional molded product.

The insert sheet 1 comprises a base film 11
The pattern layer 12, the adhesive layer 13 and the like are sequentially formed on the top (see FIG. 2). The base film 11 is used as a base film of an ordinary insert sheet, and may be a plastic film such as polyethylene terephthalate. The pattern layer 12 is formed by a usual forming method such as printing in order to form a pattern, a painting, a logo, characters, symbols and the like on the surface of the molded product. The pattern layer 12 is
It may have a metal layer formed by vacuum vapor deposition. The adhesive layer 13 is for adhering the insert sheet 1 to the surface of the molded product at the same time when the molded product is molded, and is formed by a normal forming method such as printing using a resin of the same type as the resin constituting the molded product. To be done.

The preform of the insert sheet 1 is formed by a press molding apparatus 3 (see FIGS. 3A and 4B) consisting of a core mold 31 and a cavity mold 32, or a normal resin such as a vacuum molding device. Preforming means for shaping the sheet into a desired three-dimensional shape may be used. Cavity mold 32
Is a concave portion 4 of a female die 41 of an injection molding die 4 for injection molding a desired three-dimensional molded product 6 (see FIG. 1C) described later.
The preform shape of the insert sheet 1 having the recess 30 having the same inner surface shape as that of 0 is the injection molding die 4 described later.
The inner shape of the concave portion 40 of the female die 41 is closely fitted to the shape. To facilitate preforming, the insert sheet 1 may be heated during press forming or vacuum forming.

The trimming of the insert sheet 1 is performed by a press cutting device 2 (FIG. 3) having a knife or a cutting blade 21.
(B), FIG. 4 (a)), peripheral edge 80 of mold A8 and mold B
9 (sliding cutting die for cutting with the peripheral edge 90 (see FIG. 6), heating cutting device, laser cutting device, etc.)
A normal resin sheet cutting means may be used. The trimming shape of the insert sheet 1 is a shape that does not at least protrude from the peripheral edge 60 of the surface of a desired three-dimensional molded product 6 (see FIG. 1C) obtained by the injection molding die 4 described later. For example, when the three-dimensional molded product 6 is a button-shaped molded product having a top surface 61 and a frustoconical skirt portion 62, the insert sheet 1 covers the top surface 61 and the skirt portion 62 of the three-dimensional molded product 6, and The shape is such that it does not protrude from the peripheral edge 60 of the skirt portion 62 and does not become a tongue shape. In addition, although a flange portion may be provided on the peripheral edge of the insert sheet 1 after trimming,
After the injection molding, it is necessary to prevent the end of the flange from protruding beyond the peripheral edge 60 of the skirt 62 of the three-dimensional molded product 6.

Either the preforming or trimming of the core type insert sheet 1 may be performed first, but the core type 301 with a cutting blade and the desired three-dimensional molded product 6 described later.
It is also possible to use the preform press die including the recess 40 of the female die 41 of the injection molding die 4 for injection molding and the cavity die 302 having the recess 300 having exactly the same inner surface shape. (Fig. 5
(See (a) and (b)).

Next, the insert sheet 1 (FIG. 1) that has been preformed and trimmed as described above is used.
(See (a), FIG. 3 (b), FIG. 4 (c), and FIG. 5 (c))
Is mounted on an injection molding die 4 including a female die 41 having a recess 40 for molding a desired three-dimensional molded product 6 and a male die 42 having a resin injection port 43 (see FIG. 1).

Since the insert sheet 1 has already been preformed so as to match the concave portion 40 of the female die 41, it is fitted into the concave portion 40 of the female die 41 by an appropriate conveying device (not shown) or a robot. Just enough.

Next, after closing the recess 40 and the male mold 42 of the female mold 41 to which the insert sheet 1 is mounted, the three-dimensional molded product 6 is obtained by injecting the molding resin 5 between the injection molding dies 4.
The insert sheet 1 is formed on the surface at the same time as the formation (see FIG. 1B).

The adhesive layer 13 of the insert sheet 1 is melted by the heat of the resin when the molding resin 5 is injected, and the adhesive layer 13 adheres to the surface of the molded product as the molding resin cools and solidifies. Examples of the molding resin 5 include acrylonitrile styrene resin, polycarbonate resin, polystyrene resin, acrylic resin, polyester resin and the like.

Finally, waiting for the cooling and solidification of the molding resin 5,
The injection molding die 4 is opened and the insert molded product 7 having the insert sheet 1 formed on the surface of the three-dimensional molded product 6 is taken out.

[0019]

According to the method for producing an insert-molded product of the present invention, the insert sheet in which at least the picture layer and the adhesive layer are formed on the base sheet is used as a female member having a recess for molding a desired three-dimensional molded product. It is mounted on an injection molding die consisting of a mold and a male mold, and after the mold is closed, a molding resin is injected between the molds to form a three-dimensional molded product and at the same time an insert molded product with an insert sheet formed on its surface. In the manufacturing method, before mounting the insert sheet between the female mold and the male mold, the insert sheet is preformed so as to match the inner surface shape of the concave portion of the female mold, and the desired three-dimensional molded article is formed. Trimming was performed so that it would not protrude from the peripheral edge of the surface of.

Therefore, according to the present invention, before the insert sheet is mounted between the female mold and the male mold, the insert sheet is protruded from the peripheral edge of the surface of the desired three-dimensional molded product at a place different from the injection molding die. Since it is trimmed so that it does not exist, the following effects are achieved. 1. The cutting blade clearance is not affected by heat. Therefore, the blade does not spill. Also, the insert sheet can be cut cleanly. Also, since the insert sheet from which unnecessary cutting dust has been removed is set in the injection mold,
A beautiful molded product with no cutting dust attached can be obtained.

2. Economical because no special injection mold is required.

3. Since no part for cutting the insert sheet is incorporated in the injection molding die, the structure of the injection molding die is simple, and an insert molded article of any shape can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an injection molding process of a method for manufacturing an insert-molded product according to the present invention.

FIG. 2 is a cross-sectional view showing an insert sheet used in the method for manufacturing an insert-molded product according to the present invention.

FIG. 3 is a cross-sectional view showing a preform step and a trimming step of the method for manufacturing an insert-molded product according to the present invention.

FIG. 4 is a cross-sectional view showing a preforming step and a trimming step of the method for manufacturing an insert-molded product according to the present invention.

FIG. 5 is a cross-sectional view showing a preforming step and a trimming step of the method for manufacturing an insert-molded product according to the present invention.

FIG. 6 is a cross-sectional view showing a mold for performing a trimming step of the method for manufacturing an insert-molded product according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insert sheet 11 Base film 12 Picture layer 13 Adhesive layer 2 Press cutting device 21 Cutting blade 3 Press molding device 30 Recess 31 Core type 32 Cavity type 300 Recess 301 Core type with cutting blade 302 Cavity type 4 Injection molding die 40 Recess 41 Female mold 42 Male mold 43 Resin injection port 5 Molding resin 6 Three-dimensional molded product 60 Peripheral 61 Top surface 62 Skirt part 7 Insert molded product 8 Mold A 80 Margin 9 Mold B 90 Margin

Claims (2)

[Claims] 1. An injection molding die comprising a female mold and a male mold having a recess for molding a desired three-dimensional molded product of an insert sheet having at least a pattern layer and an adhesive layer formed on a base material sheet. In the method of manufacturing an insert-molded product in which a three-dimensional molded product is formed by injecting a molding resin between the molds after the mold is closed, and an insert sheet is formed on the surface of the molded product, Before mounting the insert sheet in between, preform the insert sheet to match the inner surface shape of the concave portion of the female mold,
Moreover, the method for producing an insert-molded product is characterized in that trimming is performed so as not to protrude from the peripheral edge of the surface of the desired three-dimensional molded product. 2. The method for producing an insert-molded article according to claim 1, wherein the preform and trimming of the insert sheet are simultaneously performed by using a preform die having a cutting blade.