JPH04336220A - Method for molding filler-containing resin molded product - Google Patents

Abstract

PURPOSE:To mold a filler-containing resin molded product having good appearance prevented from the end part of a filler from protruding from the surface of the molded product with good working efficiency. CONSTITUTION:A heating plate 8 heated to the thermal deformation temp. of a resin or higher is placed to the inner surface parts of injection molds 1, 2 corresponding to the surface ready to improve appearance of a resin molded product and a filler-containing resin is injected in the injection molds 1, 2 to be molded and solidified.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a filled resin molded article containing a filler such as glass fiber.

0002

2. Description of the Related Art Conventionally, resin products in which glass fiber or the like is contained as a filler have been used as garnish parts for vehicles and the like.

[0003] Such resin products containing glass fibers are
Usually, as shown in FIG.
It is manufactured by a so-called injection molding method in which glass fiber-containing resin is injected into a molded article 5 using an injection machine 3.

0004

However, in the molded product manufactured in this manner, the ends 7a of the glass fibers 7 protrude from the surface of the resin molded product 5, as shown in FIG. There are defects that result in poor appearance and feel.

[0005] Therefore, in order to eliminate the protrusion of glass fibers, methods such as heating the mold beforehand during molding are used, but it takes a considerable amount of time to warm up the mold. Furthermore, it takes time to cool down the mold to a certain degree before proceeding to the next step, which causes a problem in that work efficiency is significantly reduced.

The present invention was devised in view of these problems, and by placing a preheated heating plate on the inner surface of the mold and injection molding the filled resin, the work time can be shortened and An object of the present invention is to provide a method for molding a filled resin molded product in which the ends of the filler do not protrude onto the surface of the product.

[0007]

[Means for Solving the Problems] Therefore, the method for molding a filled resin molded article of the present invention involves injection molding a resin containing a filler into an injection mold to form a resin molded article. In the method of molding a resin-filled molded product, a heating plate heated to a temperature equal to or higher than the heat deformation temperature of the resin is placed on the inner surface of the injection mold corresponding to the surface on which the appearance of the resin molded product is to be improved; The method is characterized in that a filler-containing resin is injected into the injection mold and solidified.

[0008]

[Function] In the above-described method for molding a filled resin molded article of the present invention, the heating plate heated above the thermal deformation temperature of the resin increases the fluidity of the resin surface that hits this part during molding, and the filler is molded. It is buried in the product and does not protrude from the surface of the molded product even after molding.

[0009]

[Example] An embodiment of the present invention will be described below with reference to the drawings. Figures 1 and 2 show the molding process of a method for molding a filled resin molded article as an embodiment of the present invention. FIG. 1 is a schematic diagram showing the state of the mold before molding in which a heating plate is placed in the mold, and FIG. 2 is a schematic diagram showing the state of the mold during molding when the filler-containing resin is injected. FIG. 3 is a sectional view of a molded product according to the present invention, and in FIGS. 1 to 3, the same reference numerals as in FIGS. 4 and 5 indicate substantially similar parts.

Now, in FIGS. 1 and 2, 1 shows an example of a female mold, 2 shows an example of a male mold, and 3 shows an injection machine.

FIG. 1 shows a state before molding in which both molds 1 and 2 are disassembled. First, in this state, a molded product 5 is
The inner surface of the female mold 1, which corresponds to the surface where the appearance is to be improved, that is, the surface where the end of the glass fiber is to be prevented from protruding, is heated by high-frequency induction heating or the like to a temperature higher than the heat deformation temperature of the resin to be molded. For example, although it differs somewhat depending on the resin, in the case of ABS resin, a metal plate 8 heated to around 150° C. is placed and brought into contact.

Next, as shown in FIG. 2, both the molds 1 and 2 are put together, and the glass fiber 7, that is, the resin 5 containing the filler is injected into the molds 1 and 2 from the injection machine 3 through the injection port 2a. When injection molded into 2, glass fiber 7 is formed on the surface as shown in FIG.
A resin molded product 5 is molded in which the ends of the resin molded product 5 do not protrude at all.

The reason why the ends of the glass fibers 7 do not protrude from the surface of the resin molded product 5 is that the fluidity of the resin surface that is molded by receiving heat from the heating plate (metal plate) 8 during molding increases. This is because the glass fibers 7 are completely buried in the resin molded product, so that the surface of the resin molded product 5 is manufactured to have a good appearance and feel.

In this case, the use of a metal plate as the heating plate 8 has been exemplified, but this does not have to be a metal plate, and it is also possible to use a resin or film that does not adhere to the resin to be molded and is resistant to temperature. good.

[0015] If the surface of the molded product is uneven,
In other words, if the inner surface of the mold on which the heating plate 8 is placed has an uneven surface, an upright pin is provided at the concave portion of the inner surface of the mold, although not particularly shown, and a pin is provided at the corresponding location on the heating plate 8. The injection molding may be performed after inserting a hole and defining the position of the heating plate 8.

According to the present molding method in which molding is performed as described above, molding can be performed efficiently by a method without time loss in which the heating plate 8 is heated in advance in a separate process and placed in the mold. This eliminates the need for the traditional process of repeatedly performing the time-consuming process of heating and cooling the mold, which greatly improves productivity. In addition, it is possible to quickly produce a filled resin molded product with a good appearance without the ends of the filler protruding from the surface, and it is also useful for producing good quality products and reducing product costs.

[0017]

[Effects of the Invention] As detailed above, according to the method for molding a filled resin molded article of the present invention, a resin molded article is molded by injection molding a resin containing a filler in an injection molding mold. In a method for molding a filled resin molded product, a heating plate heated to a temperature equal to or higher than the heat deformation temperature of the resin is placed on the inner surface of the injection mold corresponding to the surface on which the appearance of the resin molded product is to be improved. The filler-containing resin is then injected into the injection mold and solidified, so filling can be done easily and efficiently by placing a preheated heating plate at the desired location in the mold in a separate process. This method has the advantage of being able to produce good quality resin molded products at low cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a pre-molding process according to an embodiment of the method for molding a filled resin molded article of the present invention.

FIG. 2 is a schematic diagram showing steps during molding according to an embodiment of the method for molding a filled resin molded article of the present invention.

FIG. 3 is a sectional view of a filled resin molded product according to the present invention.

FIG. 4 is a schematic diagram showing steps during molding according to a conventional example.

FIG. 5 is a sectional view of a conventional filled resin molded product.

[Explanation of symbols]

1 Female mold 2 Male mold 2a Injection port 3 Injection machine 5 Molded products 7 Filler (glass fiber) 7a End of filler (glass fiber) 8 Heating plate

Claims (1)

[Claims] Claim 1: In a method for forming a resin molded product by injection molding a resin containing a filler in an injection mold, the surface of the resin molded product is used to improve the appearance of the resin molded product. A heating plate heated to a temperature equal to or higher than the heat deformation temperature of the resin is placed on the inner surface of the injection mold corresponding to the mold, and the filler-containing resin is injected into the injection mold and solidified. A method of molding a filled resin molded product.