JPH0513803B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to fiber-reinforced plastic products reinforced with fiber materials such as glass fibers, and in particular, the product has a high content of reinforcing fibers and is less prone to cracks. The present invention relates to a fiber-reinforced plastic product that is molded using the resin injection method and has high strength.

[Prior art]

One of the methods for molding fiber-reinforced plastics is the resin injection method. In the resin injecting method, a predetermined amount of reinforcing fiber material such as glass fiber is loaded in advance into a void having the shape of a molded product formed by a mold, and an appropriate amount of liquid thermosetting resin is hardened into the void. This is a method of injecting a mixed liquid resin made by mixing materials and causing it to react and harden to form the product.

The strength of the fiber-reinforced plastic product molded by the above method depends on the filling rate of the reinforcing fiber material. That is, increasing the filling rate of the reinforcing fiber material increases the strength of the molded product.

Conventionally, in order to increase this filling rate, as shown in FIG. 5, a method has been adopted in which a plurality of mats 51 made of glass fibers are stacked one on top of the other and loaded into the void.

[Problems to be Solved by the Invention] However, as shown in FIG. Although the filling rate is relatively high, the filling rate decreases as the shape becomes more complex, and it is also difficult to load the reinforcing fiber material into the voids to increase the filling rate.

In addition, as shown in FIG. 5, it is not enough to simply load a plurality of mats 51, ... into the void of the mold in an overlapping manner, and if a liquid resin is injected therein and a product is formed by reaction hardening, the sixth As shown in the figure, a resin rich portion 52 is provided between the mats 51 and 51.
As a result, cracks are likely to occur in the resin rich portion 52. Another drawback is that once a crack occurs, it spreads along the resin rich portion 52, resulting in poor strength of the molded product.

The present invention has been made in view of the above points, eliminates the above problems, has a high filling rate of reinforcing fiber material,
To provide a fiber-reinforced plastic product molded by a strong resin injection method, which is hard to generate cracks and does not spread even if cracks occur.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention fills in advance a predetermined amount of reinforcing fiber material into a void having the shape of a molded product formed by a molding die, and adds an appropriate amount of a curing agent to a liquid thermosetting resin into the void. In fiber-reinforced plastic products that are molded by the resin injection method in which a mixed liquid resin is injected and molded, a mat made of a reinforcing fiber material such as glass fiber is used as a reinforcing fiber material to fill the voids, as shown in Figure 1. It is characterized by using a reinforcing material made by stacking a plurality of mats 2, .

Further, the present invention is characterized in that a plurality of reinforcing materials sewn into the quilted shape are stacked and loaded so that the sewn portions and the quilted convex portions overlap each other.

[Effect]

As shown in Fig. 1, the reinforcing fiber material to be filled into the voids as described above is stacked with a plurality of mats made of reinforcing fiber materials such as glass fibers, and the stacked mats are sewn into a quilt shape. Even if a resin rich part occurs between the mats and a crack occurs in this part, the gap between the mats in the sewing part is zero or very small, so the resin rich part will not occur in this part. Any cracks that occur will be stopped in this area and will not spread further.

Furthermore, since a plurality of mats made of reinforcing fiber material are stacked one on top of the other and sewn into a quilted shape, the filling efficiency of reinforcing fibers is improved. In particular, by stacking a plurality of pieces sewn into a quilt shape so that the sewn parts and the quilt convex parts overlap each other, the filling efficiency is improved and at the same time, the voids between the reinforcing materials are reduced, so naturally the resin rich part is also reduced.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a diagram showing a reinforcing fiber material used in fiber-reinforced plastic products. As shown in the figure, the reinforcing fiber material 1 is made by stacking a plurality of mats 2 made of glass fiber fibers and stacking the mats together. are sewn using an industrial sewing machine or the like, and the sewing section 3 sews the mat stack into a so-called quilted shape that divides the stacked mat into a large number of small sections.

As shown in FIG. 2, a plurality of reinforcing fiber materials 1 having the above-mentioned structure are stacked and loaded into a gap having the shape of a molded product formed by a mold so that the sewn portions 3 and the convex portions overlap each other.

FIG. 3 is a sectional view showing a mold portion of a resin injection device for molding a fiber-reinforced plastic product using the reinforcing fiber material 1. As shown in FIG.
As shown in the figure, the mold is composed of an upper mold 11, a lower mold 12, and a core mold 13.
1 and the lower mold 12 form a void 1 having the shape of a molded product.
4 is formed. Further, the lower mold 12 is provided with resin injection ports 15, . . . , and the upper mold 11 is provided with air vent holes 16, .

As shown in FIG. 2, a plurality of reinforcing fiber materials 1 are loaded into the gap 14 in advance by stacking them so that the sewn portions 3 and the convex portions overlap each other.

After loading the reinforcing fiber material 1 into the void 14 as described above, a liquid mixed resin made by mixing a predetermined amount of a curing agent with a liquid thermosetting resin is passed through the resin injection port 15 using an injection machine (not shown). Inject into the cavity 14. The cavity 14 is filled with this mixed liquid resin, and a fiber-reinforced plastic product is completed by reaction curing.

In the fiber-reinforced plastic product molded as described above, the reinforcing fiber material 1 is made by stacking a plurality of mats 2 made of glass fiber fibers and sewing them into a quilted shape as described above. The fiber content can be significantly increased, resulting in extremely strong fiber-reinforced plastic products.

Conventionally, when bulky glass fiber mats 2 were used, it was extremely difficult to increase the glass fiber content of fiber-reinforced plastics to 30% or more. 1, it is possible to increase the glass fiber content up to 50%.

In addition, as shown in FIG. 2, since a plurality of reinforcing fiber materials 1 are stacked and loaded so that the sewn portions 3 and the convex portions overlap with each other, the filling rate is improved, and the reinforcing fiber materials 1 and reinforcing fibers When the mixed liquid resin is injected without creating a large gap between the materials 1, the resin rich portion becomes smaller. Also,
Because multiple mats 2 made of glass fibers are stacked and sewn into a quilted shape,
A resin rich portion 4 is formed between the mats 2 shown in FIG. 4, and the progress of cracks generated in the resin rich portion 4 is stopped at the sewing portion 3. Therefore, even if a crack occurs in the resin-rich portion, its expansion is limited to a predetermined small range, thereby further improving the strength of the molded product. Further, since a plurality of mats 2 made of glass fibers are sewn into a quilted shape, filling the voids 14 with reinforcing fiber material becomes easy.

It should be noted that the reinforcing fiber material of the fiber-reinforced plastic product according to the present invention is not limited to glass fiber, and it goes without saying that other reinforcing fiber materials may be used.

〔Effect of the invention〕

As explained above, according to the present invention, a reinforcing material is used in which a plurality of mats made of reinforcing fibers are stacked together and the stacked mats are sewn into a quilted shape. Compared to loading bulky pine, the following superior effects can be obtained.

Reinforcement fiber material and loading work can be shortened.

The reinforcing fibers will not peel off from the mold surface.

The reinforcing fiber material can be easily loaded without requiring special techniques.

Since the content of the reinforcing fiber material in the molded product can be greatly increased, resin-rich areas are reduced and defects in the molded product, such as cracks and shrinkage, are greatly reduced.

In order to increase the density of the reinforcing material, which is strongly sewn into a quilted shape, multiple reinforcing materials are stacked and loaded so that the sewn parts and the convex parts of the quilting overlap each other. This reduces the chance that the injection pressure will force the mats downstream of the resin flow and cause differences in the density of the reinforcing fibers, such as would occur if bulky mats were loaded. .

[Brief explanation of the drawing]

Figure 1 is a diagram showing reinforcing fiber materials used in fiber-reinforced plastic products, Figure 2 is a diagram showing a stacked state of reinforcing fiber materials, and Figure 3 is a resin injector for molding fiber-reinforced plastic products. FIG. 4 is a cross-sectional view showing the mold part of the device; FIG. 4 is a diagram for explaining the resin rich portion that occurs in the reinforcing fiber material; FIG. 5 is a diagram showing a conventional reinforcing fiber material having a structure in which multiple mats are stacked; FIG. 6 is a diagram showing how a resin rich portion occurs when a conventional reinforcing fiber material is loaded. In the figure, 1... Reinforcing fiber material, 2... Reinforcing fiber mat, 3... Sewing part, 4... Resin rich part, 1
1... Upper mold, 12... Lower mold, 13... Core mold, 1
4...Void.

Claims (1)

[Scope of Claims] 1 A predetermined amount of reinforcing fiber material is filled in advance into a void having the shape of a molded product formed by a mold, and a liquid thermosetting resin is mixed with an appropriate amount of a curing agent in the void. In a fiber-reinforced plastic product molded by a resin injection method in which liquid resin is injected and molded, a plurality of mats made of reinforcing fibers are stacked together as a reinforcing fiber material to be filled in the voids, and the mat made by stacking the plurality of mats is A fiber-reinforced plastic product molded using the resin injecting method, which uses reinforcing fiber material sewn into a quilt shape. 2. The resin according to claim 1, wherein a plurality of reinforcing materials sewn in the shape of a quilt are stacked one on top of the other so that the sewn portion and the convex portion of the quilt overlap each other as the reinforcing fiber material to be filled in the void. A fiber-reinforced plastic product molded using the in-die extension method. 3. A fiber-reinforced plastic product molded by a resin injection method according to claim 1 or 2, wherein the reinforcing fibers of the mat are glass fibers.