JPH06190931A - Fiber-reinforced thermoplastic resin pipe and manufacture thereof - Google Patents

Abstract

PURPOSE:To enable easy execution of reform and to reduce labor for preforming by a method wherein a plurality of prepregs being long longitudinally and preformed so that a prescribed fiber intersection angle be obtained are disposed in a space formed by a thermally expansible mandrel and an outer die. CONSTITUTION:A thermoplastic prepreg 1A of a prescribed width is wound spirally on a tapered mandrel 2a so that a prescribed fiber intersection angle be obtained to the direction of the axis. This thermoplastic prepreg 1A is heated to be reformed by roasting it from one end toward the other end side by a drier in such a degree that the resin of a matrix is not melted. The resin of the matrix is thermoplastic resin and a crystalline polymer, a noncrystalline polymer, a semi-crystalline polymer having intermediate properties of these polymers, or others, are used for the thermoplastic prepreg 1A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber reinforced thermoplastic resin pipe using a plurality of parts made of thermoplastic prepreg and a method for producing the same, and more particularly to a fiber having improved pipe quality and productivity. The present invention relates to a reinforced thermoplastic resin pipe and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, golf club shafts aimed at weight reduction are mainly made of thermosetting prepreg (FRP) made by reinforcing thermosetting resin such as epoxy resin or polyester resin with glass fiber or carbon fiber. Is made. However, such a golf club shaft made of FRP has a problem in that it is insufficient in flexibility and impact absorption. To solve these problems, it is considered effective to use thermoplastic prepreg (FRTP) as a raw material. However, when molding a golf club shaft from a thermoplastic prepreg, the difficult points are firstly formed into a thin cross-sectional shape, secondly formed into a tapered tubular body, and thirdly a special lamination. It is to request. In particular, when thermoplastic prepreg (FRTP) using high-performance (high elastic modulus) carbon fiber is used as a material, the problems in each of these points are significant.

The above-mentioned point of forming the thin cross-sectional shape is dealt with by preforming or preforming represented by the habit forming of the thermoplastic prepreg. This is a measure against the fact that the bending shape cannot be maintained with a slight force due to the decrease in bending curvature. Further, the influence of the tapered tubular body is a change in the fiber crossing angle that is inevitably generated when the unidirectional prepreg (UD prepreg) is used for winding.

As a result, the uniformity in the circumferential direction of the cross section (uniformity) is destroyed to some extent. The fundamental solution is to adjust the fiber crossing angle according to the taper shape, but it is not possible to use a prepreg, which is costly and not a realistic method. In addition, the requirement for special lamination is based on the mechanical requirements peculiar to the golf club shaft, and due to the structure of the golf club shaft, due to the deviation of the hitting point and the shaft axis, torque is generated at the time of hitting, Similarly, a bending moment is generated upon hitting. It is the laminated structure based on 45 ° and 0 ° that realizes sufficient rigidity and strength against such an impact input.

In the production of a hollow body made of thermoplastic prepreg (FRTP), especially in the case of a golf club shaft, it is difficult to integrate and integrate ± 45 ° (a so-called lamination component that overcomes torque) in combination with thinness. The 45 ° spirally wound fiber, when pressed against the outer mold, easily bites into the mandrel and significantly weakens the integration pressure.

In view of the above points, the applicant of the present application filed a thermoplastic resin as a matrix in the application of the golf club shaft and the manufacturing method thereof in Japanese Patent Application No. 21041037/1992 (JP-A-4-96772). A golf club shaft formed of a fiber-reinforced thermoplastic resin hollow body molded with a prepreg to be wound, and a prepreg having a thermoplastic resin as a matrix is wound, and the obtained hollow wound product is put into a cavity of an outer mold, A heat-expandable core was inserted into the hollow part of the wound material, and then the hollow wound material and the core were heated to a temperature not lower than the plasticizing temperature of the thermoplastic resin to expand the core. After that, a method for manufacturing a golf club shaft, which is manufactured by cooling the core and the hollow wound product, is proposed.

[0007]

However, when the prepreg is wound in a taper shape by the method of the above application, the laminating angle is shifted as the prepreg is wound,
There is a problem that it is difficult to obtain uniformity such as bending rigidity of the product, and it is difficult to stack at a high angle for producing torque of the shaft.

The present invention has been devised in view of the above-mentioned conventional problems, and it is possible to easily give a habit to a thermoplastic prepreg, reduce the labor of preform molding, and form a taper shape. The productivity of pipes can be improved, and high-angle stacking can be performed easily.
An object of the present invention is to provide a fiber reinforced thermoplastic resin pipe capable of molding a product having high uniformity and a method for producing the same.

[0009]

In order to achieve the above-mentioned object, the present invention provides a plurality of vertically elongated thermoplastic prepregs preformed so that the fiber crossing angle becomes a predetermined angle with respect to the axial direction. The gist is that it is placed in the space between the expansive mandrel and the outer mold, heated to the molding temperature of the material, then cooled and integrally molded.

[0010]

The present invention is constructed as described above, and the thermoplastic prepreg having a habit is cut into a predetermined length,
A plurality of vertical gutter-shaped part bodies made of thermoplastic prepreg with a predetermined fiber angle are molded, and the plurality of parts bodies thus molded are laminated on the outer peripheral surface of the mandrel for shaft molding. The mandrel for forming the shaft and the laminated body of the body of the parts are inserted into the outer mold, heated and compression-molded, and then cooled to integrally form a hollow tapered pipe, thereby forming a habit of the thermoplastic prepreg. In addition to being easy to attach, it is possible to reduce the labor of preform molding, improve the productivity of tapered pipes, easily perform high-angle stacking, and to ensure uniformity. It is possible to mold high products.

[0011]

Embodiments of the golf club shaft and the method for manufacturing the golf club shaft according to the present invention will be described below with reference to the accompanying drawings. The thermoplastic prepreg used in the golf club shaft according to the present invention (prepreg having a thermoplastic resin as a matrix) is
Specifically, a fiber bundle generally called tow in which multiple continuous fibers are aligned and arranged in a strip in one direction is impregnated with a matrix thermoplastic resin (unidirectionally aligned prepreg (UD prepreg)). Etc. are used.

The reinforcing fiber used in the fiber bundle constituting the thermoplastic prepreg is not particularly limited, but preferably carbon fiber, glass fiber, aramid fiber (aromatic polyamide fiber), silicon carbide fiber, boron fiber, liquid crystal fiber.
(Whole aromatic polyester), alumina fiber, and other continuous fibers having heat resistance and high strength and elastic modulus can be exemplified.

The thermoplastic resin for the matrix is not particularly limited, but is preferably polyether ether ketone (PEEK) having a melting point of 343 ° C., and a melting point of 282-288 ° C.
Polyphenylene sulfide (PPS) with a softening point of 219 ℃
Polyetherimide (PEI), Polyethersulfone
High melting point of (PES), polyarylene ketone, polyarylene sulfide, polyallylimide, polyamideimide (PAI), polyimide, polyimide sulfone, polysulfone, polyallyl sulfone, nylon (66,6), polycarbonate, polyester, etc. Alternatively, a thermoplastic resin having a high softening point can be exemplified.

The thermoplastic prepreg differs from a general prepreg having a thermosetting resin as a matrix in that it not only lacks drape property (suppleness) and tackiness (adhesiveness), but is itself continuous. Since it is a thin sheet of thermoplastic resin reinforced with fibers, it is very rigid and has a property of easily tearing along the fibers. The manufacturing method of the present invention is the same as the carbon fiber / epoxy shaft for the purpose of using the final product, but the same process cannot be taken due to the difference in materials.

That is, in the conventional product, the molding temperature is 120 to 17
While the temperature is 0 ° C., it is several degrees higher in the present invention, which is 300 ° C. to 400 ° C. Further, the method of the present invention in which molding and shaping are carried out stepwise by repeating heating and cooling several times is a method utilizing the characteristics of the thermoplastic matrix and cannot be applied in the case of thermosetting. That is, in the present invention, the characteristics of the thermoplastic matrix in terms of shaping are particularly utilized.

The golf club shaft 1 using the thermoplastic prepreg described above has a plurality of parts so that the fiber crossing angle is a predetermined angle (for example, ± 45 °) with respect to the axial direction (longitudinal direction). A vertically long thermoplastic prepreg 1A in which the main body 1a is arranged and integrally formed, and a plurality of parts main bodies 1b having a fiber crossing angle of 0 ° with respect to the axial direction.
And a plurality of vertically elongated thermoplastic prepregs 1B which are integrally formed by alternately arranging the above-described components are laminated, heated and compressed, and cooled to integrally form a tapered hollow golf club shaft. .

In the embodiment of the present invention, the fiber crossing angle is ±
At 45 ° or equivalent, the length of the fiber is at most half circumference, so the molding pressure is not weakened, and even if the length of the fiber becomes a little shorter, the thermoplastic prepreg has toughness. Cuts and bonds between fibers are fully covered. Next, a method for manufacturing the golf club shaft 1 will be described in the order of steps with reference to FIGS.

First, as shown in FIG. 1, a thermoplastic prepreg 1A having a predetermined width (12.7 mm in this embodiment) is attached to a tapered mandrel 2a at a predetermined fiber crossing angle with respect to the axial direction (longitudinal direction). The thermoplastic prepreg 1A is spirally wound so as to form an angle, and the thermoplastic prepreg 1A is heated by a dryer so that the resin of the matrix does not melt, and is heated to form a habit.

The matrix resin is a thermoplastic resin, and those used for such a thermoplastic prepreg 1A include crystalline polymers, amorphous polymers and semi-crystalline polymers having an intermediate property between them. When heated to a temperature slightly below the melting point in the deformed state, the stress is relaxed and thermal deformation occurs. When the thermoplastic prepreg 1A is bent, tensile stress is generated on the convex surface portion and compressive stress is generated on the concave surface portion. In this state, when heated to a temperature slightly below the melting point (or softening point), the stress of the matrix resin relaxes, and even if the constraint that holds the winding shape is released, it does not return to the original flat plate shape,
The shape of the roll remains, and in this way, a curl can be added.

Fine wrinkles and the like are generated on the surface of the thermoplastic prepreg 1A, but macroscopically, the wrinkles are merely changes in gloss and are preformed on the mandrel 2a to form a beautifully curved spiral. A thermoplastic prepreg 1A in the form of a strip is obtained. If the thermoplastic prepreg 1A is wound around the tapered mandrel 2a in a right-handed or left-handed manner, the spiral thermoplastic prepreg 1 in each direction is wound.
A can be obtained.

Next, the prepreged thermoplastic prepreg 1
A is cut into a predetermined length at X ₁ -X ₁ and X ₂ -X ₂ in FIG. 1 to obtain a thermoplastic prepreg 1A as shown in FIG.
A plurality of parts main bodies 1a composed of are molded. The parts main body 1a is arranged adjacent to each other in a trough-shaped mold 3 as shown in FIGS. 3 and 4 so that the fiber angle is a predetermined angle (for example, ± 45 °). The main body 1a is integrated by spot welding such as a soldering iron by heat fusion to form a vertically elongated gutter-shaped first part P having a fiber angle of ± 45 °.
1. Form a plurality of sheets. In this embodiment, the first gutter-shaped first portion forming a half circumference of the golf club shaft 1.
The part P1 is molded.

On the other hand, as shown in FIG. 5, a thermoplastic prepreg 1B having a predetermined width is provided on a tapered mandrel 2a (for example, 8 mmΦ) with a fiber crossing angle of 0 ° with respect to the axial direction.
It is wound so that it will be roasted from one end to the other end with a dryer to form a peculiarity, and this peculiar thermoplastic prepreg is cut into a predetermined length, and the fiber crossing angle is At 0 °, in this embodiment, a vertically elongated gutter-shaped second part P2 that forms a half circumference of the golf club shaft 1 is formed. In this way, a vertically elongated gutter-shaped second part P2 composed of a plurality of thermoplastic prepregs 1B.
Multiple sheets are molded.

Next, as shown in FIGS. 6 and 7, a plurality of molded first parts P1 and second parts P2 are connected to each other by connecting portions S between the first parts P1 and the second parts P2.
a and Sb are alternately arranged on the outer peripheral surface of the shaft forming mandrel 4 to be laminated twice or twice, and the entire circumference of the shaft forming mandrel 4 is covered with a soldering iron or the like. Temporarily stop. In addition, the first part P1,
For repeated stacking with the second part P2, it is preferable that the cross sections of the fibers be displaced by 1/4 rotation as shown in FIG.

Thereafter, the laminated body of the first part P1 and the second part P2 wound around the mandrel 4 for shaft molding is inserted into an outer mold and compression-molded by heating in the same manner as the conventional method, and then cooled. Then, the mandrel 4 is pulled out to integrally form the hollow tapered golf club shaft 1. In the above embodiment, the first part P1
, And two second parts P2 are used for each layer, but the present invention is not limited to this, and it is also possible to mold using three or more parts as shown in FIG. .

Further, only a part of the parts can be constituted by a vertically elongated member, for example, a high-angle prepreg is constituted by a vertically elongated member, and a part having an angle of 0 ° is wound in the conventional manner. Is also good. FIGS. 10 to 12 show a gutter-shaped part 1Z obtained by forming a thermoplastic prepreg 1C into a wavy shape and cutting this prepreg sheet 1D at predetermined positions Y ₁ -Y _1.
In this molding method, the thermoplastic prepreg 1C is inserted between the upper and lower molds 6a, 6b of the corrugated uneven portions 5a, 5b and hot-pressed to form the corrugated shape as shown in FIG. The prepreg sheet 1D having a habit is formed. Then, the predetermined position Y _{1 of the} prepreg sheet 1D
-Y ₁ is cut to form a gutter-shaped part 1Z, which is formed into a shape similar to that of the above-described embodiment shown in FIGS.

In the case of molding by such a method, without using the tapered mandrel 2a as in the above embodiment, the prepreg-made thermoplastic prepreg 1A is cut into a predetermined length. It is not necessary to mold a plurality of part bodies 1a made of the thermoplastic prepreg 1A as shown in FIG. 2, and productivity and workability can be improved.

After forming a plurality of gutter-shaped parts 1Z, the hollow taper-shaped golf club shaft 1 is integrally formed by inserting it into an outer mold and heat-compressing it in the same manner as in the above embodiment. It is to be molded as desired. The method for manufacturing a golf club shaft molded as described above is also applicable to fishing rods, racket handles, bicycle frame pipes, and the like.

[0028]

According to the present invention, a golf club shaft using a prepreg part having a thermoplastic resin as a matrix is manufactured by the above-described method, so that the thermoplastic prepreg can be easily formed. At the same time, the effort of preform molding can be reduced, the productivity of golf club shafts can be improved, high-angle stacking can be easily performed, and products with high uniformity can be molded. There is.

[Brief description of drawings]

FIG. 1 A prepreg sheet having a thermoplastic resin as a matrix is spirally wound around a tapered mandrel so that a fiber crossing angle becomes a predetermined angle with respect to an axial direction (longitudinal direction), and heated to form a habit. It is explanatory drawing which shows the process to attach.

[Figure 2] in X ₁ -X ₁ and X ₂ -X ₂ in Fig. 1 is cut to a predetermined length, the part made of thermoplastic prepreg shows a plurality molding to process, (a) represents, FIG 1 shows a part of the A ₁ part, (b) shows a part of the A ₂ part of FIG. 1, and (c) shows a part of the A ₃ part of FIG. 1.

FIG. 3 The parts shown in FIG. 2 are arranged adjacent to each other in a trough-shaped mold so that the fiber angle is a predetermined angle, and the parts are integrated by heat fusion by spot welding such as a soldering iron. It is explanatory drawing which shows the process made.

FIG. 4 is a perspective view showing a first part of a vertically elongated gutter shape for a half circumference of a golf club shaft, in which parts are integrated by spot welding such as a soldering iron by heat fusion.

FIG. 5 is a perspective view showing a vertically elongated gutter-shaped first part for a half circumference of a golf club shaft, which is integrated by spot welding such as a soldering iron by heat welding.

FIG. 6 shows a step of forming a second part by winding a thermoplastic prepreg of a predetermined width around a taper-shaped mandrel so that the fiber crossing angle becomes 0 ° with respect to the axial direction, and heating to form a habit. It is an explanatory view shown.

FIG. 7: A plurality of molded first parts and second parts are alternately arranged on the outer peripheral surface of the mandrel for shaft molding so as to cover the connecting parts of the first parts and the second parts. It is a partially cutaway perspective view showing a step of stacking layers.

8 is a cross-sectional view taken along the line YY of FIG.

FIG. 9 is a view similar to the cross-sectional view taken along the line YY of FIG. 7 showing another embodiment.

FIG. 10 is a perspective view of upper and lower molds for forming a thermoplastic prepreg into a wavy shape according to another embodiment of the present invention.

FIG. 11 is a partial perspective view of a thermoplastic prepreg habituated by upper and lower molds.

FIG. 12 is a perspective view of a gutter-shaped part when the thermoplastic prepreg habituated by the upper and lower molds of FIG. 12 is cut at a predetermined position.

[Explanation of symbols]

1A thermoplastic prepreg 1a part 1B thermoplastic prepreg 1b part 2a mandrel 3 gutter-shaped mold 4 mandrel P1 first part P2 second part

Claims (2)

[Claims] 1. A plurality of vertically elongated thermoplastic prepregs preformed so that the fiber crossing angle becomes a predetermined angle with respect to the axial direction, are arranged in a space between a thermally expandable mandrel and an outer mold, A fiber reinforced thermoplastic resin pipe formed by heating to the molding temperature of the material, then cooling and integrally molding. 2. A plurality of vertically elongated gutter-shaped part bodies formed of thermoplastic prepregs each having a predetermined fiber angle are formed by cutting the pliable thermoplastic prepreg into a predetermined length. A plurality of molded parts main bodies are laminated on the outer peripheral surface of a shaft forming mandrel, and the laminated body of the shaft forming mandrel and the parts main body is inserted into an outer mold for heat compression molding, and then cooled. Thus, a method for producing a fiber-reinforced thermoplastic resin pipe is characterized in that a hollow tapered pipe is integrally molded.