JPS6028562A - Stitching method of reinforced fiber substrate laminate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for sewing a laminate of reinforcing fiber base materials,
More specifically, the present invention relates to a method of suturing a laminate of sheet-like reinforcing fiber base materials used for molding an m-fiber reinforced resin using a hair needle and a sewing thread.

When molding II fiber-reinforced resin (hereinafter referred to as FRP), sheet-shaped reinforced GI fiber base materials, such as reinforcing fiber fabrics, are laminated, the laminate is impregnated with resin and then heated and pressurized, or woven prepreg is laminated. A method is often adopted in which the laminate is then heated and pressurized. In this case, regardless of whether the base material is woven fabric or its prepreg, the base materials are laminated one by one during molding, with the fiber axes of the reinforcing fibers oriented in the desired direction. is very troublesome, so
The base materials may be laminated in advance and sewn together. The stitching operation of the laminate of reinforcing fiber base materials is necessary in such cases.

Conventionally, the above-mentioned sewing operation of the laminate is performed using a commercial sewing machine. However, the method using a sewing machine has the disadvantage of damaging the reinforcing fibers.

In other words, when using a sewing machine, due to the structure of the sewing machine, the sewing thread threaded through the needle is held at a distance of 60 to 60 mm against the surface of the laminate together with the needle.
Since the laminate is penetrated at an angle of 75°, the sewing thread and the base material are significantly rubbed during the penetration, and the reinforcement 1 navy blue is damaged. It is especially hot when the base material is thick or when the reinforcing fibers that make up the base material are fibers with low elongation at break, such as amorphous fibers.

If the reinforcing fibers are damaged, FRP, which has high physical properties,
Not only is it not possible to obtain F1<1], but also the variation in physical property values among each F1<1] becomes large.

An object of the present invention is to provide a suturing method that solves the above-mentioned drawbacks of the conventional methods and is less likely to damage reinforcing fibers.

In order to achieve the above object, the present invention provides a sheet-shaped reinforcing fiber for mechanically reinforced resin. , (Method of suturing a laminate of materials using a beard needle and sewing thread) A step of penetrating the beard 11 in the orthogonal direction and capturing the beard needle sewing thread of A; ■ The step of moving the whisker needle or the laminate in the direction of the surface of the laminate at a distance approximately equivalent to the suture pitch (the step of moving only the whisker needle to the other side of the laminate). The method is characterized in that the steps of repeatedly passing through the suture thread, capturing the suture thread again, pulling it back to one side, forming a loop of the suture thread on the negative side, and engaging the loop with the loop are repeated. A method of suturing a laminate of reinforcing fibers 11 [base material] is provided.

To explain the method of this invention using drawings, FIG.
It is a schematic perspective view showing an example of a hair needle used in the method of this invention, and FIGS. 2 to 8 are schematic explanatory views showing the suturing operation according to the method of this invention in order.

In FIG. 1, a beard needle 1 has a stem 2, an eye 3 provided at the tip of the stem 2, a head 4, and a hook-shaped pair 5. The head 4 is formed into an acute angle so as to easily pass the reinforcing fiber base material laminate through L'4. Further, the pair 5 is bent in the direction of the eye 3 to prevent damage to the reinforcing fibers when penetrating the laminate and to easily catch the sewing thread, and its tip is housed in the eye 3.

Now, referring to FIG. 2, in the method J3 of the present invention, first, the laminate 7 of the sea 1-shaped reinforced fiber navy blue base material to be sewn is placed on the suturing table 6. This laminate 7 is held down by a holding plate 8. The beard needle 1 is disposed on one side of the laminate 7, and the sewing thread guide 10 is disposed on the faith side at a position substantially facing the beard sword 1.

The above base material can be carbon fiber, glass fiber, organic high modulus fiber (
The laminate is made of a high-strength, high-elasticity, delicate (multifilament) woven fabric such as polyaramid fiber (for example, polyaramid fiber), and the laminate is made by laminating such woven fabrics so that the fiber axes are oriented in a desired direction. However, the base material does not have to be a textile, and may be, for example, a mat. Also,
The reinforcing fibers are arranged parallel to each other in one direction in a sheet shape,
It may be a so-called unidirectional bripreg obtained by impregnating this with a B-stage thermosetting resin, or the above-mentioned fabric or mat prepreg. Furthermore, the base materials forming the 4δ laminate do not necessarily have to be of the same type, and base materials of different types may be combined.

The sewing thread may be made of synthetic fibers such as nylon 1JJi fibers or polyester fibers, but it is preferably made of double-stranded reinforcing fibers, and moreover, multifilaments. That is, when the sewing thread is composed of reinforcing fibers, the sewing thread extends in the lamination direction of the base material when FRP is molded, and the interlaminar shear strength and living room peel strength of the FRP are improved.

Furthermore, since the sewing thread has a greater degree of curvature than the reinforcing fibers that make up the base material, if stress is applied to the base material after suturing, the stress will be concentrated at the bent part, and the base material may break from that part. be. In order to prevent this, the sewing thread preferably has a greater elongation at break than the reinforcing fibers constituting the base material. Furthermore, if the sewing thread shrinks excessively due to heat during molding, the arrangement of reinforcing fibers in the base material may be disturbed. Therefore, the sewing thread preferably has a shrinkage rate of 2% or less at 120°C. To give a specific example, when the base material is made of carbon lIi navy blue, a sewing thread made of glass fiber or polyaramid fiber is suitable.

Now, in this invention, from the state shown in FIG. 2 to the state shown in FIG. 3, the beard! 11 is penetrated from one side of the laminate 7 toward the other side in a direction substantially perpendicular to the surface of the laminate 7. Then, the Baird 5 of the hair needle 1 captures the sewing thread 9 on the other side of the laminate 7,
As shown in FIG. 4, the whiskers 11 are pulled back to one side of the laminate 7. At this time, since the sewing thread 9 passes through the hole made by the hair needle 1, it can easily pass through the laminate without rubbing harshly against the thread. As a result, a loop of the sewing thread 9 is formed on one side of the laminate 7. The length of this loop is equal to or slightly longer than the stitching pitch of the laminate 7. In other words,
It has a length approximately equivalent to the suture pitch.

Next, as shown in FIG. 5, the whisker needle 1 or the laminate 7 is moved in the plane direction of the laminate by a distance approximately corresponding to the suture stitch.

Next, as shown in FIG. 6, only the hair hook 1 is passed through the other side of the laminate 7 again, and as shown in FIG. - On the side,
Form a loop of thread 9 similar to that described in FIG. This loop is formed within the previously formed loop, so when the needle 1 or the laminate 7 is moved by a distance approximately corresponding to the suture stitch, both loops will be closed as shown in FIG. engage, and suturing is completed.

By repeating the above operations, the laminate 7 can be sewn together at a predetermined pitch.

In the above, the suture speed, that is, the whisker needle is fl! i
If the number of times the layer is penetrated is too high, the reinforcing fiber shoulder 1 of the base material is likely to be damaged, and if it is too low, the efficiency will not be improved. Although it depends on the type of base material and laminate, it is preferably about 5 to 200 times per minute.

Furthermore, if the base material is made of prepreg, the highly viscous B-stage resin will prevent the hair needle from passing through the eyebrows. For this reason, it is necessary to set the beard and/or the laminate to a temperature that prevents the resin from transferring to the C-stage.
1, for example, preferably about 80 to 120°C.

As explained above, the method of the present invention allows hair nails to be moved from one side of a laminate of sheet-like reinforced IJM base materials toward the other side, and in a direction substantially perpendicular to the surface of the laminate. The needle is inserted through the needle, the sewing thread is captured, and the thread is pulled back to one side.In other words, the hole through which the sewing thread is inserted is previously formed with the thread needle, so it is difficult to insert the thread into the base material. There is almost no abrasion between the material and the sewing thread, and there is little risk of damage to the 11 feet of reinforcement that makes up the base material. Such damage to the reinforcing fibers can be avoided by forming a loop with a length approximately equivalent to the suture pitch on the suture thread that has been pulled back to the negative side, and then moving the whisker needle or the laminate by a distance approximately equivalent to the suture pitch. This is further reduced because no extra tension is applied.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing an example of a beard needle used in the present invention, and FIGS. 2 to 8 are schematic explanatory views showing the method of the present invention in order. 1: Beard needle 2: Stem 3: Eye 4: Head 5: Paired 6: H1 combination stand 7: Laminated body 8: Presser plate 9: Sewing thread 10: Sewing thread guide

Claims (1)

[Scope of Claims] A method of suturing a laminate of sheet-like reinforcing fiber base materials for fiber-reinforced resin using a hair needle and sewing thread, the method comprising: a step of penetrating the laminate needle in a direction substantially perpendicular to the surface of the laminate and capturing the sewing thread with the laminate needle; , a step of forming a loop of suture thread with a length approximately corresponding to the suture pitch, and ■ a step of moving the needle or the laminate in the plane direction of the laminate and a distance approximately equivalent to the suture pitch. , ■ Pass only the hair needle through the other side of the laminate again, capture the suture thread again and pull it back to the first side, form a loop of the suture thread on the negative side, and engage the loop with the loop. A method for suturing a laminate of reinforcing fiber base materials, the method comprising repeatedly performing the steps of: