JPH10202692A - Molding of filament reinforced molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the strength and elastic modulus of a molding. SOLUTION: A core metal 1 allowed to approximate to the shape of a product to be molded is formed. A filament prepreg 2 formed by mixing long fibers 2a with a thermoplastic resin to arrange them is wound around the outside of the core metal 1 to form a plurality of layers and the filament prepregs 2 of the respective layers are mutually bonded to be integrated and the core metal 1 is extracted to form a hollow long fiber reinforced layer 3. This long fiber reinforced layer 3 is set to the inside of an injection mold and a resin 4 is injected into the long fiber reinforced layer 3 from an injection molding machine to deform the long fiber reinforced layer 3 to obtain a molding 9 wherein the injection molded resin 4 and the long fiber reinforced layer 3 are integrated.

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 an injection-molded article reinforced with long fibers.

[0002]

2. Description of the Related Art Conventionally, when a molded article is molded by an injection molding method, a resin injected from an injection molding machine is injected and filled into an injection mold having a split structure.
It is common to open the injection mold and take out the molded product inside, but recently, as a method of improving the tensile strength of the molded product by injection molding, the molded product is poured into the above-mentioned mold. It has been practiced to mix 10 to 40% of short fibers into a resin to mold.

[0003]

However, when short fibers are mixed as reinforcing fibers, the tensile strength can be improved about twice, but other strengths such as bending, compression, impact, etc. There is a tendency to be equal to or rather lower than when no reinforcing fibers are mixed, and sufficient reinforcement has not been achieved.

Accordingly, an object of the present invention is to provide a method for molding a high-strength, high-elasticity and lightweight injection-molded article by using an injection molding method.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a long fiber prepreg obtained by impregnating a long fiber with a thermoplastic resin as a reinforcing material to approximate the shape of a product to be molded. On the outside of the cored bar, a plurality of layers are superposed so that the direction of the long fiber is oblique and the long fiber prepregs are attached to each other, and then the core is pulled out to form a hollow long fiber reinforced layer, and then After setting the long fiber reinforced layer in an injection mold, the same or compatible resin as the resin of the long fiber prepreg is injected by an injection molding machine and injected into the long fiber reinforced layer, A method of deforming the long fiber reinforced layer into a shape in the injection molding die and molding a molded article in which the long fiber reinforced layer and the injection resin are integrated.

Since the long fiber reinforced layer is formed by laminating and adhering a plurality of long fiber prepregs, the resin injected therein does not leak, and the long fibers are inclined. The resin can be easily stretched in the direction in which it is stretched when it is molded by injecting a resin into the resin, and the strength and elastic modulus can be improved. In addition, since molding can be performed only by injecting the injection molding resin into the long fiber reinforced layer, the molding time can be reduced, the product shape can be stabilized, and the weight can be further reduced.

A long fiber prepreg obtained by impregnating a long fiber with a thermoplastic resin as a reinforcing material is made of a resin having the same or good compatibility with the resin of the long fiber prepreg by approximating the shape of a product to be molded. On the outside of the manufactured cored bar, a plurality of layers are superposed so that the direction of the long fiber is oblique and partially removed and wound to form a long fiber reinforced layer, and then the long fiber reinforced layer is placed in an injection mold. After setting, the temperature of the injection molding mold is raised to melt the resin of the core metal, and then the same resin as the resin of the core metal is injected by an injection molding machine and injected into the long fiber reinforced layer. Accordingly, when the long fiber reinforced layer is deformed into a shape in the injection molding die, and the long fiber reinforced layer, the resin of the core metal, and a method of molding a molded article integrally with the injection resin are used, The extraction process can be omitted and the core metal melts Since leaving the fiber-reinforced layer, since it is sufficient to inject the injection-molded resin by shortage, it is possible to reduce the amount of injection-molded resin.

Further, by inserting the nozzle of the injection molding machine deeply into the long fiber reinforced layer and pulling out the nozzle with the injection, the nozzle can be reliably injected into the long fiber reinforced layer. become able to.

[0009]

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

FIG. 1 shows a molding process according to an embodiment of the present invention. The outline of the molding method of the present invention is as follows. On the outside, a long fiber prepreg 2 made by impregnating a long fiber with a thermoplastic resin as a reinforcing material is wound around a plurality of layers except for a part, and the long fiber prepregs 2 are adhered to each other. 1 is pulled out to form a long fiber reinforced layer 3 having a hollow inside. Next, after setting the long fiber reinforced layer 3 in an injection mold, an injection molded resin 4 is injected into the long fiber reinforced layer 3 to deform the long fiber reinforced layer, thereby forming a molded article. To do.

In detail, for example, when forming a stationary vane of a compressor, first, as shown in FIG. 1 (a), a metal made of metal is formed so as to have an outer shape similar to the stationary vane of a compressor as a product. A mandrel 1 is made, and a long fiber prepreg 2 made by impregnating a long fiber 2a with a thermoplastic resin as a reinforcing material is formed on the outside of the mandrel 1 so that the direction of the long fiber 2a is oblique. While wrapping, leaving one end part, wrapping around two or three layers and superimposing. In this case, the direction of each long fiber 2a of the long fiber prepreg 2 to be superimposed on each layer is made to cross each other as shown by a solid line and a broken line in FIG.

Next, heat is applied to the long fiber prepreg 2 wound around the core 1 from the outside to adhere and integrate the long fiber prepregs 2 of each layer, and then the core 1 is extracted. As shown in FIG. 1 (c), a long fiber reinforced layer 3 having a hollow inside is formed.

Next, the hollow long-fiber reinforced layer 3 is set inside an injection mold 5 having a split structure shown in FIG. Then, the nozzle 7 of the injection molding machine 8 is inserted through the hole 6 at one end of the injection molding die 5, and then the injection molding die 5 is heated to be slightly soft so that the internal long fiber reinforced layer 3 can be expanded and contracted. In this state, the injection molding resin 8 is injected from the injection molding machine 8 and injected into the hollow long-fiber reinforced layer 3 from the nozzle 7 so that the long-fiber reinforced layer 3 is inserted into the injection molding die 5. And deformed to conform to the shape of.
At this time, the long fiber reinforced layer 3 is made of the long fiber prepreg 2 by 2 to 3
Since the long fibers 2a are obliquely oriented and intersect between the prepregs to be laminated, the resin injected into the inside does not leak to the outside, and is expanded and molded. The long fiber reinforced layer 3 can be easily stretched in the direction in which it is stretched when molded in the mold 5. The resin 4 to be injected and used is the same as or compatible with the resin of the long fiber prepreg 2. If short fibers are mixed into the resin 4 as a reinforcing material, the strength is more effective.

When the injection of the resin 4 into the hollow long fiber reinforced layer 3 is completed and the molding is performed in the molding die 5, the injection molding die 5 is released, and the long fiber reinforced layer Molded product 9 shown in FIG. 1D in which the injection molding resin 3 and the injection molding resin 4 are integrated.
To take out.

In the above-described molding method, when the resin 4 from the injection molding machine 8 does not easily enter the inside of the hollow long fiber reinforced layer 3, the nozzle 7 of the injection molding machine 8 is made longer.
In advance, it is inserted up to the deepest part in the long fiber reinforced layer 3,
If the resin 4 is injected while the nozzle 7 is retracted during the injection molding, the resin 4 can be surely injected to every corner.

The method for forming a long-fiber-reinforced molded product of the present invention is not limited to the above-described embodiment.
For example, the core metal 1 used for forming the long fiber reinforced layer 3 is made of the same resin as the resin 4 injected into the long fiber reinforced layer 3, and outside the resin core, Similarly, the long fiber prepreg 2 may be wound to form a long fiber reinforced layer. In this case, in order to melt the core 1 of the long fiber reinforced layer 3 put in the injection molding die 5 before injecting the resin from the injection molding machine, the temperature in the molding die 5 is increased to increase the core 1. Melts the resin making the long fiber reinforced layer 3
Then, the resin 4 is injected from the injection molding machine 8 into the inside of the long fiber reinforced layer 3 in the mold to expand the long fiber reinforced layer 3 and to inject the injected resin 4 into the long fiber reinforced layer 3. It is integrated with the resin of the metal core 1.

According to this method, when the metal core 1 is used, the work of pulling out the core 1 becomes unnecessary, and the resin forming the core melts and the long fiber reinforced layer is formed similarly to the injected resin. 3, the amount of the resin 4 injected by the injection molding machine 8 can be reduced.

[0018]

As described above, according to the method for forming a long-fiber-reinforced molded article of the present invention, a long-fiber prepreg is superimposed on a plurality of layers by using a core bar so that the long-fiber is oblique and in a plurality of layers. The long fiber prepregs of the respective layers are attached to each other, the core metal is extracted to form a hollow long fiber reinforced layer, the long fiber reinforced layer is set in an injection molding die, and a resin injected from an injection molding machine. Is injected into the hollow portion of the long fiber reinforced layer to deform and mold the long fiber reinforced layer in the injection mold, so that a molded product reinforced with long fibers is obtained. In addition to improving the strength and elastic modulus of the product, the weight of the product can be reduced because the inside of the product is injection-molded resin. Can stretch, and
An excellent effect of shortening the molding time can be obtained, and the core metal is made of the same or compatible with the fiber of the long fiber prepreg, so that the core fiber can be melted without being pulled out and melted. In this state, the injection amount of the injection molding resin can be reduced, and the long fiber reinforced layer is easily stretched and increases the strength by making the direction of the long fiber cross each layer. By inserting the nozzle of the injection molding machine deeply into the long fiber reinforced layer and retracting the nozzle in the drawing direction with the injection of the resin, the inside of the long fiber reinforced layer can be removed. In addition, the resin can be reliably injected.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a molding process showing one embodiment of a molding method of the present invention, wherein (a) is a schematic diagram of a core, and (b) is a plurality of layers of long fiber prepreg outside the core. (C) is a diagram showing a state in which a core is extracted to form a hollow long fiber reinforced layer, and (D) is a diagram in which an injection molding resin is injected into the long fiber reinforced layer and molded. It is a figure showing a molded article.

FIG. 2 is a cross-sectional view showing a state in which a long fiber reinforced layer is set in an injection mold and injection molding is performed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Core metal 2 Long fiber prepreg 2a Long fiber 3 Long fiber reinforcement layer 4 Injection molding resin 5 Injection molding die 7 Nozzle 8 Injection molding machine 9 Molded product

Claims (4)

[Claims] 1. A long fiber prepreg obtained by impregnating a long fiber with a thermoplastic resin as a reinforcing material, so that the direction of the long fiber is oblique to the outside of a core metal approximated to the shape of a product to be molded. The long fiber prepregs were adhered to each other by laminating a plurality of layers, and then the core metal was removed to form a hollow long fiber reinforced layer, and then the long fiber reinforced layer was set in an injection mold. After that, a resin having the same or a good compatibility with the resin of the long fiber prepreg is injected by an injection molding machine and injected into the long fiber reinforced layer, and the long fiber reinforced layer is deformed into a shape in the injection molding die. And forming a molded article in which the long fiber reinforced layer and the injection resin are integrated. 2. A long fiber prepreg obtained by impregnating a long fiber with a thermoplastic resin as a reinforcing material is made of a resin having the same or a good compatibility with the resin of the long fiber prepreg by approximating the shape of a product to be molded. On the outside of the manufactured cored bar, a plurality of layers are superposed so that the direction of the long fiber is oblique and partially removed and wound to form a long fiber reinforced layer, and then the long fiber reinforced layer is placed in an injection mold. After setting, the temperature of the injection molding mold is raised to melt the resin of the core metal, and then the same resin as the resin of the core metal is injected by an injection molding machine and injected into the long fiber reinforced layer. The long fiber is characterized in that the long fiber reinforced layer is deformed into a shape in the injection molding die, and a molded article is formed by integrating the long fiber reinforced layer, the core resin, and the injected resin. Molding method for reinforced molded products. 3. The method for forming a long fiber reinforced molded product according to claim 1, wherein the long fiber prepregs are overlapped so that the directions of the long fibers cross each layer. 4. A long nozzle according to claim 1, wherein the nozzle of the injection molding machine is previously inserted deeply into the hollow portion of the long fiber reinforced layer, and the nozzle is pulled out as the resin is injected. Molding method of fiber reinforced molded product.