JPH0655453B2 - Molding method for fiber reinforced plastics - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fiber reinforced plastics, in particular, a fiber reinforced plastics (hereinafter abbreviated as FRP) using long fibers, and a filament winding method (hereinafter FW). Method), especially a method capable of performing so-called composite winding in which low-angle winding and high-angle winding are combined in a short time and with high accuracy.

[Conventional technology]

Examples of high-performance FRP molding methods include press molding and resin injection, but for rotationally symmetric products such as cylinders, the FW method is used because of the uniformity and arbitrariness of the fiber arrangement and the high volume fiber content ratio. Has been adopted.

In the FW method, as shown in FIG. 5, the long fibers A supplied from the supply unit 1 are passed through a resin bath 2 and impregnated with resin,
After further aligning, they are passed through the eye 4 of the reciprocating carriage traverse 3 and the long fibers bundled through the eye are wound on the mandrel 5 which is rotating to a predetermined thickness and then heated. Then, the matrix resin is cured, and then the mold is removed.

The structural FRP obtained by the FW method is used for the purpose of receiving a force in two directions, the circumferential direction and the axial direction, except for some cases. There is a difference of about 10/1 in both strength and elastic modulus. Therefore, as a high-angle and low-angle composite winding, high-angle winding (hoop length) provides circumferential performance, and a low angle that is usually 40 ° or less. Square winding (helical winding) often secures axial performance.

By the way, in the FW method, although the tape width of the wound fiber is uniquely determined by the structure of the eye, conventionally,
Also in complex winding, an eye 4 similar to a well-known drawing die is used, as shown in FIG. 6, in which the inner surface (guide surface of the fiber) of the circular ring base is formed into an arc, and this is used for hoop winding fiber and helical winding. It is also used to bundle fibers.

[Problems to be solved by the invention]

When mass producing FRP based on the FW method,
First of all, it may be considered to speed up the winding, but this method not only impairs the impregnation of the resin into the fiber but also causes fluffing of the fiber and the like, leading to a decrease in the performance of the FRP. Therefore, as the next means, there is no choice but to consider widening the winding tape.

However, as described above, if the hoop winding and the helical winding are performed by sharing the eye of FIG. 6, the following problems will occur. That is, first, when considering the helical path, the fibers introduced into the eye hit the inner surface of the eye and are focused and ejected here, but in low-angle helical winding, the winding tension applied to the fiber on the mandrel surface. Is smaller than the hoop winding portion, while the focusing property at the eye portion is larger than that at the hoop winding portion. Therefore, the tape width (wall thickness) of the helical winding
Is narrower than the width of a hoop winding tape, which is not so wide, making it difficult to wind the hoop and helical tapes at the same pitch without uneven arrangement of the tapes, and as the number of fiber bundles increases, the alignment becomes even. Is getting harder.

Also, in the hoop winding, the tape width is set to 1 pitch, but when the tape width becomes wider, the difference angle of the hoop winding naturally becomes smaller, and in order to obtain a high quality FRP with fiber orientation as designed, That also becomes a problem.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the above-mentioned problems and enable long-term composite winding of long fibers with high precision.

[Means for Solving the Problems] A method of the present invention for achieving the above-mentioned object is to provide a carriage traverse adopted in the FW method with an eye as shown in FIG. Eye 1 with void 11
Long fibers A in which 0 is provided and resin is impregnated in the void of this eye
At least one of them is passed through, and a helical path A'is passed through a portion 11a of the space perpendicular to the mandrel rotation axis C, and a hoop path A "is passed through a portion 11b parallel to the axis C.

In addition, it is desirable that the void portion 11 has a symmetrical shape with the axis line S perpendicular to the axis C as a reference line. In particular, it is extremely effective for solving the above-mentioned problem that the portion 11b parallel to the mandrel rotation axis C includes a linear portion as shown in FIG. Is.

In addition, the guide surfaces of the respective parts 11a and 11b in contact with the fibers,
It is also important to set the curved surface as shown in FIG. 2 where the fibers are slippery. Such a curved surface may be provided on a plate-shaped eye base material by machining, electric discharge machining, or the like. However, as shown in FIG. 4, bending the round wire makes it easier to manufacture the eye. .

[Action]

According to the above-described method of the present invention, when the helically wound fiber is wound, the matching (drawing) of the fibers in the mandrel rotation axis direction is performed at the eye portion that acts to weaken the focusing force at the winding portion. On the other hand, by utilizing the distance between the outlet points (see FIG. 2), the fibers can be aligned accurately in the spreading direction by adding the fibers to the vertical portion 11a of the void portion where the focusing force is weak. . Moreover, the spread width of the fibers can be made larger than in the conventional case by forming the vertical portion 11a into a shape including a straight portion. Therefore, by adjusting the installation pitch that is equal to the value of the mandrel rotation axis direction of the void portion 11, it is possible to perform helical winding having the same spread as when winding a narrow tape.

Further, in the hoop winding, since the protrusion is made at the portion 11b parallel to the mandrel rotation axis of the air gap, the shape of the portion 11b is the same as that of the conventional eye, or if necessary, the straight portion as shown in FIG. 3 is formed. By including the shape, the tape width can be expanded. The problem of a decrease in the winding angle due to the widening of the hoop winding portion is that, in the case of the present invention, butt winding is performed at each lead-out portion. In other words, in the case of FIG. 1 as an example. , The second fiber from the right is hoop-wound on the hoop-wound layer of the rightmost fiber, and the hoop-wound layer of the third fiber from the right is further formed on this layer. Since it is converted to multiple winding, it does not occur at all.

Therefore, it is possible to make the tape widths of the hoop and the helical wide by using one set of eyes and at the same time, and efficiently wind the tapes at the same pitch, thereby achieving the above object.

[Effect] As described above, the method of the present invention employs an eye in which a plurality of voids having a portion perpendicular to the mandrel rotation axis and a portion parallel to the mandrel rotation axis are arranged in parallel to widen the tape width of the hoop and the helical. At the same time, it is possible to accurately align them and keep them in the same width, so it is possible to mold a rotary axis symmetrical body that requires high-angle and low-angle composite winding with high accuracy and high efficiency.
It can greatly contribute to the stabilization of FRP quality and the implementation of mass production.

[Brief description of drawings]

FIG. 1 is a diagram showing the basic concept of the method of the present invention, FIG. 2 is a sectional view taken along line XX of the eye of FIG. 1, and FIG. 3 is a plan view showing another embodiment of the eye. FIG. 4 is a perspective view showing still another embodiment of the eye, FIG. 5 (a) is a side view showing the outline of the FW method, and FIG. 4 (b) is a front view of the mandrel part of (a). , FIG. 6 is a sectional view showing an example of a conventional eye structure. 1 ... Supply Department, 2 ... Resin Bath, 3 ... Carry Traverse, 5 ... Mandrel, 10 ... Eye, 11
... Void, 11a ... Vertical part with respect to mandrel rotation axis, 11b ... Parallel part with mandrel rotation axis, A ...
… Long fiber, A ′ …… Helix path part of long fiber, A ″ ……
Long fiber hoop path part.

Claims (3)

[Claims] 1. A method for molding fiber-reinforced plastics, comprising winding a plurality of resin-impregnated continuous fibers around an outer peripheral surface of a mandrel rotating through a reciprocating carriage traverse and curing / molding the fiber. An eye having a plurality of parallel voids is provided in the carriage traverse, and at least one continuous fiber impregnated with resin is passed through each void of this eye, and a helical portion is provided in the void perpendicular to the mandrel rotation axis. A molding method for fiber reinforced plastics, characterized in that the paths pass through the hoop paths in parallel. 2. Each of the void portions has a straight portion in a portion perpendicular to the rotation axis of the mandrel, and has a symmetrical shape with the vertical axis as a reference line including a portion parallel to the rotation axis. A method for molding fiber-reinforced plastics according to claim (1). 3. The method for molding fiber reinforced plastics according to claim 1 or 2, wherein the fiber guide surface of the void is a curved surface.