JPH0596643A - Molding method for frp hollow object - Google Patents

Abstract

(57) [Summary] [Purpose] Efficiently mold a lightweight and highly rigid FRP hollow product. [Structure] A heater 4 is provided on each joint end face of a pair of molds 1 provided with a molding part having a divided shape of a hollow molded product and a vacuum deaeration port 3 connected to the molding part, and a peripheral part of both surfaces is provided with a heater 4. A molding material 7 reinforced with a glass fiber mat using a thermoplastic resin as a matrix resin is arranged on both sides of the partition plate 5 to which a material layer 6 having a good releasability is attached and set between the molds.
After the mold is clamped and vacuum degassed to mold each molding material, the mold is opened and the partition plate is taken out of the mold, and then the mold is clamped again and the butt surface of each molded product is heated by the heater. FRP hollow product is obtained by fusing.

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 hollow product made of FRP (glass fiber reinforced resin).

[0002]

2. Description of the Related Art Recently, FRP is used for automobile outer panels and bumpers.
(Glass fiber reinforced resin) products have come into use. In addition, synthetic resin products are required to be recyclable materials from the viewpoint of waste treatment. In order to improve the fuel efficiency of automobiles, the need to reduce the weight of the car body is increasing, and structural materials such as chassis and frames are FR.
P conversion has been achieved. In order to enable recycling and satisfy both weight reduction and high rigidity, it is necessary to use a thermoplastic resin reinforced with a glass mat as a material and make the product into a hollow structure. The conventional hollow resin product construction method and the evaluation of the product are shown in Table 1 below.

[0003]

[Table 1]

FIG. 2 shows a method of manufacturing a hollow structure product by vacuum forming shown in Table 1. In FIG. 2A, a cavity 12 is formed in a mold 11, and an exhaust hole 13 for vacuum deaeration is formed in the cavity 12.
To provide. A glass frame mat W impregnated with resin is fixed to the molding die 11 by a support frame 14, and the molding material W is heated by a heater 10. Next, as shown in FIG. 2B, the softened material W
Is sucked into the cavity 12 and a U-shaped molded product W '
Is molded into. Similarly, a molded product W ″ paired with W ′ is molded, and as shown in FIG. 2C, the open ends of the molded products W ′ and W ″ are butted and bonded with an adhesive 15, or by a vibration fusion method. And joined to make a hollow structure product.

Japanese Unexamined Patent Publication No. 60-189431 discloses a method for producing a hollow resin product as shown in FIG. In FIG. 3A, the middle mold 2 is provided between the upper mold 21 and the lower mold 22.
3, the cavities 24 and 25 are formed by the middle mold 23 and the upper and lower molds respectively, and molten resin is injected into these to mold molded products 26 and 27, respectively. Next, as shown in FIG. 3B, the upper and lower molds are opened, the middle mold 23 is moved laterally in the figure while holding the molded products 26 and 27 in the upper and lower molds, and is taken out of the upper and lower molds, and the upper and lower molds are clamped again. Molded product 2
The ends of 6, 27 are joined to form a hollow product.

[0006]

In the conventional method such as blow molding, it is impossible to mold a hollow structure FRP that secures rigidity comparable to that of a steel plate and is lightweight, and in the molding method shown in FIG. As the number of processes increases, productivity will deteriorate and capital investment will increase. Further, the molding method shown in FIG. 3 is a method of injecting a molten resin into the mold, and is therefore not suitable for molding a high-strength FRP hollow product using glass fiber for reinforcement.

An object of the present invention is to solve the above problems and to provide a method for molding an FRP hollow article, which enables efficient molding of a highly rigid FRP hollow article and also reduces capital investment.

[0008]

According to the present invention, a heater is provided on each joint end face of a pair of molds provided with a molded part having a divided shape of a hollow molded product and a vacuum deaeration hole connected to the molded part. , On both sides of the partition plate having a material layer with good release property attached to the peripheral portions of both sides, a molding material reinforced with a glass fiber mat as a matrix resin of a thermoplastic resin is disposed and set between the molds, After the mold is clamped and vacuum degassed to mold each molding material, the mold is opened and the partition plate is taken out of the mold, and then the mold is clamped again and the butt surface of each molded product is heated by the heater. It is a method for molding an FRP hollow product in which the FRP is fused and joined.

[0009]

Since each molding material is partitioned by the partition plate, each molding material is independently molded by vacuum suction. It is easy to take out the partition plate after molding because it has good releasability from the molded product at the pressure contact part.Since the heater is installed in the mold, both molding products are held in each mold. A hollow molded product is obtained by joining the abutted portions of the products.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG.
In FIG. 1A, reference numerals 1 and 1 denote a pair of molding dies, each of the dies 1
In each of them, a cavity 2 and an exhaust hole 3 for vacuum deaeration connected to the bottom thereof are formed. A plate 4 with a heater is installed around the opening end surface of each mold 1. Fluorine resin layer 6 with excellent releasability around the partition plate 5 made of iron or the like
And the molding material 7, 7 on both sides of the fluorine resin layer 6.
To arrange. The partition plate is provided with vent holes 6a, 6a for communicating both sides of the partition plate 5 with the outside. Molding material 7
Is a thermoplastic resin reinforced with long-fiber glass fiber and continuous-fiber glass mat, and the matrix resin is PP, PBT, PET, PA, PC, PP.
E, PC / PBT alloy, PPO / PA alloy, etc. are used.

Next, the molding method will be described. First, the materials 7 and 7 are heated to a predetermined temperature by a far infrared heater, and are placed on both sides of the partition plate 5 as shown in FIG.
1 and then close the mold and clamp the mold as shown in FIG. 1B. Next, when vacuum degassing is performed from the exhaust hole 3, each molding material 7 is sucked and molded into a molded product 7'as shown in FIG. 1C. In this case, the space between the partition plate 5 and each molding material 7 communicates with the outside through the ventilation hole 6a, so that the molding material 7
There is no hindrance to the molding. Next, the mold is opened while vacuum degassing is performed, and the partition plate 5 is taken out of the mold. In this case, since the fluorine resin layer 6 is provided at the portion where the partition plate 5 is pressed by the mold, adhesion with each molded product 7'is prevented, and it can be easily taken out. After removing the partition plate 5 from the molds 1 and 1 as shown in FIG. 1D, the molds 1 and 1 are closed again, and as shown in FIG. 1E, the butted portion of each molded product 7 ′ is melted by the plate 4 with a heater. To wear. The FRP hollow product is obtained by opening the mold after a predetermined time and taking out the joined molded product.

At the time of molding the molding material 7 by vacuum degassing shown in FIG. 1C in the molding step, air may be blown between the partition plate 5 and each molding material 7 through the communication hole 6a. Since the fluorine resin layer 6 having good releasability is provided on both sides of the partition plate 5, the partition plate 5 can be easily taken out, and the heater-equipped plate 4 for fusing each molded product to the end surface of the mold 1 is installed. As a result, a hollow product can be obtained by using the molding die as it is, productivity is improved, and capital investment can be significantly reduced.

[0013]

Industrial Applicability According to the present invention, a lightweight and highly rigid FRP hollow product can be efficiently formed, and capital investment can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory view of a molding process of the present invention.

FIG. 2 is an explanatory view of conventional vacuum forming.

FIG. 3 is an explanatory view of conventional resin injection molding.

[Explanation of symbols]

1 Mold 2 Cavity 3 Exhaust Hole 4 Heater Plate 5 Partition Plate 6 Fluoro Resin Layer 7 Molding Material 7 '
Molding

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B29C 65/70 2126-4F // B29K 105: 06 B29L 22:00 4F (72) Inventor Eiichi Nakagawa No. 8 Tsutana, Fujisawa City, Kanagawa Prefecture, Isuzu Central Research Institute Co., Ltd. (72) Inventor Masayuki Somura No. 8 Tsutana, Fujisawa City, Kanagawa Prefecture (72) Inventor Tokuro Yamashita, Tokuro Yamasawa, Kanagawa Prefecture No. 8 In Isuzu Central Research Institute (72) Inventor Naotaka Yamamoto No. 8 Tsutana, Fujisawa City, Kanagawa Inside Isuzu Central Research Institute

Claims (1)

[Claims] 1. A heater is provided on each joint end surface of a pair of molds having a molding part having a shape obtained by dividing a hollow molded product and a vacuum deaeration hole connected to the molding part, and a mold release tool is provided on the peripheral portions of both surfaces. A molding material reinforced with a glass fiber mat using a thermoplastic resin as a matrix resin is placed on both sides of a partition plate having a material layer having good properties, set between the molds, and the molds are clamped and vacuum released. After molding each molding material by airing, the mold is opened, the partition plate is taken out of the mold, then the mold is clamped again, and the butt surfaces of the respective molded products are fused and joined by the heater. A method for molding a hollow FRP product characterized by: