JPS5830864B2 - Method for manufacturing glass fiber strands - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing glass fiber strands.

The glass fiber strand is produced by pulling out a large number of glass fibers from a bushing, applying a binder, and converging them into one or more strands.The glass fiber strand thus obtained is then traversed and inserted onto a rotating shaft and tightly attached to the tube. The tube is then rolled up and removed from the rotating shaft together with the tube, after which many products are manufactured by heating and drying the tube together.

At this time, the shape of the wound strand (hereinafter referred to as cake) is determined by how the relative position between the traversing device and the tube rotation axis is changed, i.e., the traversing period, the traversing width, the thickness of the strands, the number of strands, etc. However, in order to obtain a stable cake that does not cause the mold part of the cake to deform during handling, such as when removing the cake from the rotating shaft together with the tube, and allows for smooth unwinding in the next process, Conditions need to be established.

For this reason, it is often done to gradually increase the width of the traversing of the strand, resulting in a cross-sectional shape as shown in Figure 1 (the figure shows the cross-section of the upper part of the shaft when the cake is cut along the shaft along with the tube). However, this method has the following drawbacks.

That is, as the width of the traversing is gradually increased, the strand layer B formed on the strand layer A formed at the beginning of winding has a width slightly larger than A as shown in the figure.

Therefore, the strands forming layer A contact the tube 1 over the entire layer, while the strands forming layer B contact the tube only at their end 2, and the rest of the layer contacts the tube 1.
The strands of the layer prevent contact with the tube.

Therefore, as is clear from the drawing, this contact portion (hereinafter referred to as tube contact portion) is a very small portion of the strand that forms the B layer, and is scattered at long intervals.
It is distributed over the entire length of the strands forming the B layer.

The C layer covers the B layer. ...The same applies to the L layer strands.

When such a cake is dried, as the water evaporates, the binder attached to the glass fibers moves to the surface of the cake and concentrates near the tube, so that the strands in this part have a lower binder content than in other parts. When the cake is heated and dried in tubes, undesirable coloring sometimes occurs in this area.

Therefore, it is desirable to remove the above-mentioned portion when the strand is unwound and manufactured into a product such as roving, mat, yarn, etc.

(This area with a high binder content is called the area that requires removal).

The portion to be removed on the front side of the cake belongs to the final layer, that is, the M layer, and can be easily removed by avoiding unwinding of the strands of the M layer.

However, in the part that is in contact with the tube, A
The parts that need to be removed belonging to the layer can be completely removed by avoiding unwinding of the strands in the A layer, but the parts that need to be removed that belong to the B-L layer exist in spots over the extra length of each strand, as described above. It is actually difficult to remove this, and as a result, when these strands are used for reinforcing FRP, the removed parts get mixed into the reinforcing agent, making it difficult for this part to bond properly with the resin. This may cause defective products such as defects in product strength or undesirable colored areas on the product surface.

The present invention is a new proposal based on research to solve these difficulties.

The present invention provides a method for manufacturing a glass fiber strand, in which a large number of glass fibers are drawn out, a binder is applied thereto, the fibers are collected into one or more strands, and the strands are rolled up onto a tube and dried together with the tube. 1st stage (1j) of winding a small amount of strand onto the tube with a twill width; 2nd stage (111) of decreasing the twill width; gradually increasing the twill width from the second stage strand while winding the strand. A method of manufacturing a glass fiber strand includes a third step of winding a substantial portion of the glass fiber strand.

Next, the present invention will be explained in more detail.

A binder (
If necessary, divide and focus into a predetermined number of groups,
One or more strands.

This strand is guided to a traversing device, and while being traversed, it is wound onto a tube that is fitted and tightly attached onto a rotating shaft.

As the traversing device, for example, a guide device having a comb-shaped guide groove is used, and the guide device is rapidly reciprocated (about several hundred times per minute) in the direction of the rotation axis to perform the first traverse.
Furthermore, a suitable result can be obtained by slowly reciprocating the entire guide device in the direction of the rotation axis to effect a second traverse.

The period of the second traversing is determined depending on the rotational speed of the rotating shaft, the type of strand, etc., but it is usually appropriate to set it to about 6 to 7 times/minute.

(If you only increase the width of the first traverse by performing only the first traverse without performing the second traverse, the resulting cake will not be stable and will easily lose its shape; If you try to obtain a stable cake that does not cause oxidation, the ends of each layer tend to be exposed to the outside.

In the present invention, the first layer X is formed by winding a small amount of strand using the width of the primary and/or secondary traverse device, preferably the width of the second traverse device.

The width t1 of this removed waste X is the final traverse width 13 of the third stage.
Set it large enough so that it does not exceed 1.

The amount of strands to be wound into layer X varies depending on the size of the tube, but for example, in the case of a 30 cmφ x 30 Cn1 tube, the amount is suitably about 100 to 400 jir/cake, preferably about 200 to 300 fir/cake.

After the first layer
A layer Y is formed.

By gradually increasing the twill width, a cake having the shape shown in FIG. 2 can be rolled.

Note that it is preferable to increase the twill width in small increments as much as possible.

In the above example, it was explained that the layer Y was formed with a predetermined twill width, and then the twill width was increased little by little.
Of course, the present invention also includes a case where the twill swing width is continuously increased.

Other embodiments of the present invention include, for example, Patent No. 319.9.
A rotating set of spiral wires, such as those shown in No. 06, can be used as a traversing device, and very favorable results can be obtained as described below.

This traversing device (referred to as a spiral wire) has a property that as the tension of the strands engaged with the traversing device increases, the traversing width continuously increases.

Utilizing this property, the tension can be increased by providing a tension adjustment roll between the strand concentrator and the spiral wire, changing the position of this roll, and bending the strand between the concentrator and the spiral wire. .

Furthermore, since the tension of the strand changes depending on the relative positions of the winding tube and the spiral wire or the focusing device, the tension can be adjusted by changing these positions.

When using this method, the traverse width can be easily controlled continuously.

Since the method of the present invention is configured in this way, the strands wound in layers other than the innermost layer at the beginning of the winding do not come into contact with the tube, and the strands other than the outermost layer at the end of the winding are exposed to the front row. Therefore, when drying the cake, the part with a high binder content, which is caused by movement and concentration of the binder as water evaporates, can be concentrated only in the innermost and outermost layers, and the strand can be unwound from the cake. When used as a strand, the innermost and outermost layer parts with a high binder content can be easily removed, which prevents quality defects in the strands and products using the strands caused by these binder-rich parts. be able to.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view of a cake obtained by the conventional method, and FIG. 2 is a partial sectional view of a cake obtained by the method of the present invention.

Claims (1)

[Scope of Claims] 1. A method for producing a glass fiber strand, in which a large number of glass fibers are drawn out, a binder is applied thereto, the fibers are collected into one or more strands, and the strands are rolled up onto a tube and dried together with the tube, comprising: 1) First stage of winding a small amount of strand on the tube with a large twill width (1i) Second stage of reducing the twill width (iii)
A method for manufacturing a glass fiber strand comprising a third step of winding a substantial portion of the strand while gradually increasing the twill width from the second step. 2. A method for manufacturing a glass fiber zoot trad according to claim 1, wherein the twill width is changed by changing the tension of the strands.