JPH07205315A - Method and apparatus for producing frp tubular member - Google Patents

Abstract

PURPOSE:To obtain an FRP tubular member having desired uniform physical properties over the total length thereof and enhanced in finish accuracy up to the end parts thereof. CONSTITUTION:An engaging means 22 capable of engaging a resin impregnated reinforcing fiber bundle is attached to the end part of a mandrel 19 and, after the resin impregnated reinforcing fiber bundle is wound around the mandrel 19 so as to form a predetermined number of layers, a resin is heated and cured in such a state that the engaging means 22 is involved in the fiber bundle layers and, thereafter, the engaging means involved part is removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing an FRP (fiber reinforced plastic) tubular body, and more particularly to a method and an apparatus for producing an FRP tubular body by a filament winding molding method.

[0002]

2. Description of the Related Art A resin-impregnated bath is used to impregnate a reinforcing fiber bundle with a resin, and the resin-impregnated reinforcing fiber bundle is wound around a rotating mandrel at a predetermined angle. Manufacturing methods are known. In this molding method, usually, the resin-impregnated reinforced fiber bundle is wound on the mandrel in a predetermined number of layers at a predetermined angle, so at the end of the mandrel, the wound resin-impregnated reinforced fiber bundle is It has to be folded back.

The folding of the resin-impregnated reinforcing fiber bundle at the end of the mandrel is smoothly performed while preventing the displacement of the reinforcing fiber and the displacement of the winding angle, and the mechanical strength of the end of the molded FRP tubular body. In order to improve the above, a ring member in which a plurality of pins are planted on the outer peripheral surface is fitted to both ends of the mandrel, the resin-impregnated reinforcing fiber bundle is wound on the mandrel, and the reinforcing fiber bundle is folded back, and finally. FR the above ring member
A molding method in which the P-shaped tubular body is integrated is known (Japanese Patent Publication No. 4-15731).

[0004]

However, in the above-mentioned conventional molding method, since the ring-shaped member is finally integrated with the FRP tubular body, a ring is formed at the end of the finished FRP tubular body. A large number of pins of the strip-shaped member are embedded. Since these pins are foreign substances to the FRP tubular body, they do not necessarily lead to improvement in the mechanical strength of the FRP tubular body, and in some cases conversely may reduce the mechanical strength. At least, the part in which the pin is embedded differs in physical properties from other parts.

Further, as a result of the ring-shaped member being integrated,
Since the wall thickness of the FRP tubular body increases at least in this portion, it becomes difficult to finish the end portion of the FRP tubular body to a desired dimensional accuracy.

The object of the present invention is to solve the above problems in the conventional filament winding molding method, to obtain desired uniform physical properties over the entire length, and
It is an object of the present invention to provide a manufacturing method and a manufacturing apparatus of a tubular body made of FRP that can be finished to a desired dimensional accuracy.

[0007]

In order to achieve the above object, in the method for producing an FRP tubular body of the present invention, a mandrel is wound with a reinforcing fiber bundle impregnated with a thermosetting resin, and then the resin is heated. After curing and molding the FRP tubular body, after attaching a locking means capable of locking the resin-impregnated reinforcing fiber bundle to the end of the mandrel and winding the resin-impregnated reinforcing fiber bundle with a predetermined number of layers on the mandrel The method is characterized in that the resin is heat-cured while the locking means is still wound, and the locking means winding portion is removed after heat-curing.

The apparatus for manufacturing an FRP tubular body according to the present invention is an apparatus for forming a FRP tubular body by winding a reinforcing fiber bundle impregnated with a thermosetting resin around a mandrel and then heat curing the resin. In the above, the end portion of the mandrel is characterized in that a locking means capable of locking the resin-impregnated reinforcing fiber bundle is removably mounted after the resin is heated and cured.

In the above manufacturing apparatus, the locking means comprises a locking jig having a plurality of needle-shaped bodies provided on the outer peripheral surface of the annular body, and the locking jig is fitted on the shaft portion of the mandrel. . Alternatively, the locking means comprises a tape-shaped locking jig in which a large number of needle-shaped bodies are fixed to a tape, and the tape-shaped locking jig has a mandrel having a tip end portion of the needle-shaped body of the mandrel. It is wrapped so that it projects from the end face.

[0010]

In the FRP tubular body manufacturing method and manufacturing apparatus according to the present invention described above, the wound resin-impregnated reinforcing fiber bundle is locked by the locking means attached to the end of the mandrel. The resin-impregnated reinforcing fiber bundle is folded back in a stopped state. After being wound in a predetermined number of layers, the resin is heat-cured while the locking means is still wound.However, even during heat-curing, the wound resin-impregnated reinforced fiber bundle has locking means at the end of the mandrel. Since it is folded back in a state of being locked by, the resin is cured without releasing the winding tension during filament winding. Therefore, even at the end of the mandrel, the fiber is not disturbed and is cured while maintaining a predetermined orientation angle, and a high-performance FRP tubular body having a high expression rate of strength and elastic modulus can be obtained.

After the heating and curing, the engaging means winding portion is removed by cutting, for example, so that the FRP tubular body to be a product has uniform physical properties over the entire length. Also, by removing the locking means winding part,
The FRP tubular body product part is easily finished to a target size.

When the locking means is formed of an annular body having a plurality of needle-shaped bodies on the outer peripheral surface, for example, the shaft portion of the mandrel for fitting the locking jig formed of the annular body is formed on the tapered surface. By doing so, the locking jig can be easily pulled out in the axial direction of the mandrel even after heating and curing.

Further, when the locking means is a tape-shaped locking jig, the tape-shaped locking jig can be easily attached regardless of the diameter of the mandrel, and the molding is further facilitated. It is possible to measure. Furthermore, this tape-shaped locking jig is disposable and can be implemented at low cost.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a method and an apparatus for manufacturing an FRP tubular body of the present invention will be described below with reference to the drawings. FIG. 1 shows an apparatus for manufacturing an FRP tubular body according to an embodiment of the present invention. In FIG. 1, 1 is
1 shows a creel stand in which a large number of bobbins 2 wound with reinforcing fiber threads (for example, carbon fiber threads) are installed. Reinforcing fiber yarn 3 fed from each bobbin 2 of the creel stand 1
Are bundled to form a reinforcing fiber bundle 4 and sent to a separate roll 5. The reinforcing fiber is not limited to carbon fiber, and for example, glass fiber, aramid fiber or the like can be used, and these can be used together.

The separate roll 5 in this embodiment is a pair of free rotating rolls 6a extending substantially horizontally.
6b and a pair of free rotating rolls 7a, 7b on the downstream side thereof that extend substantially vertically. The reinforcing fiber bundles 4 which are roughly aligned in a predetermined cross-sectional shape by the separate rolls 5 are introduced into the resin impregnation bath 9 via the guide rolls 8 which are free rotating rollers.

The resin impregnated bath 9 contains an uncured resin 10 which serves as a matrix resin for the FRP tubular body. As the matrix resin, a thermosetting resin such as an epoxy resin, a phenol resin, a polyimide resin, a vinyl ester resin or an unsaturated polyester resin is used.

In the resin impregnated bath 9, in this embodiment, a roller 11 that is rotationally driven or is free to rotate.
a, 11b, and 11c are provided. Reinforcing fiber bundle 4
Are sequentially guided on these rotating rollers 11a, 11b, 11c, and the reinforcing fiber bundle 4 is impregnated with the resin 10 in the bath 9.

The reinforcing fiber bundle impregnated with the resin 10, that is, the resin impregnating reinforcing fiber bundle 12 is guided to the feed roller 14 by the guide means 13. The guide means 13 is
In this embodiment, three guides 13a, 13b, 13c are provided, and the resin-impregnated reinforcing fiber bundle 12 is guided on these guides 13a, 13b, 13c in order.

In this embodiment, of the plurality of guides 13a, 13b, 13c, two guides 13a, 13 on the upstream side are provided.
b is a rotatable roller, and the downstream side (mandrel side) guide 13c is a fixed guide.
However, the guides 13a and 13b may also be configured as fixed guides.

Pads 15a and 15b made of, for example, rubber are provided on the rollers 13a and 13b. The pads 15a and 15b are pressed by the rollers 13a and 15b with an appropriate pressing force.
Biased above 13b. These rollers 13a, 13b
The surplus resin is squeezed out by squeezing the resin-impregnated reinforcing fiber bundle 12 passing between the surfaces and the pads 15a and 15b. However, the rollers 13a, 13b
The pads 15a and 15b are not always necessary when the excess resin can be sufficiently squeezed out.

The resin-impregnated reinforcing fiber bundle 12 from the guide means 13 is guided to the feed roller 14. In this embodiment, the feed roller 14 includes the resin-impregnated reinforced fiber bundle 12
It is composed of a pair of rollers 14a and 14b arranged in the feeding direction. The pair of rollers 14a and 14b are rotatably supported by a bracket 16, and the bracket 16
Are fixed on a cylinder 18 rotatably supported by a carriage stand 17. Resin impregnated reinforced fiber bundle 1
After being inserted through the hollow portion 18a of the cylinder 18, the second member 2 is fed onto the mandrel 19 via the pair of feed rollers 14a and 14b. The feed rollers 14a and 14b are configured to move together with the cylinder 18 and the carriage stand 17 in the direction along the rotation shaft 19a of the mandrel 19.

The mandrel 19 is rotationally driven at a predetermined rotational speed by the mandrel rotational driving means 20. The mandrel rotation driving means 20 is composed of, for example, a motor or a combination of a motor and a speed reducer. By winding a predetermined number of layers on the mandrel 19 at a predetermined angle, a resin-uncured FRP tubular body 21 is formed,
By heating and curing the resin, the FRP tubular body 21
A molded product of is obtained.

In the embodiment apparatus configured as described above, a plurality of reinforcing fiber yarns 1 sent from the creel stand 1 are aligned and a reinforcing fiber bundle 4 is formed. After passing through the separate roll 5, the reinforcing fiber bundle 4 is introduced into the resin impregnation bath 9 via the guide roll 8. In the resin impregnation bath 9, the reinforcing fiber bundle 4 is impregnated with the resin 10 while being guided on the rollers 11a, 11b and 11c.

The reinforcing fiber bundle 12 impregnated with the resin 10 is
You will be guided in order on the guides 13a, 13b, 13c,
First, by passing between the rollers 13a and 13b and the pads 15a and 15b, excess resin is squeezed out at this portion. Then, by passing over the fixed guide 13c, the excess resin is squeezed at this portion and the excess resin is squeezed out efficiently. The squeezed resin is returned to the resin impregnation bath 9 below.

Since the excess resin is squeezed out from the resin-impregnated reinforced fiber bundle 12, the adhesive force of the resin-impregnated reinforced fiber bundle 12 is appropriately weakened, and the downstream feed rollers 14a, 14b.
Wrapping around is prevented.

The resin-impregnated reinforced fiber bundle 12 is further fed through the hollow portion 18a of the cylinder 18 to the feed roller 14
a, 14b, and is fed from the feed roller 14b onto the mandrel 19. The winding on the mandrel 19 is performed as shown in FIG. 2 or as shown in FIGS. 3 and 4.

In the method shown in FIG. 2, the mandrel 1
Locking jigs 22 as locking means capable of locking the resin-impregnated reinforced fiber bundles 12 are provided at the ends (both ends in the present embodiment) of 9. The locking jig 22 is composed of a member in which a plurality of needle-shaped bodies 24 are circumferentially arranged and fixed to the outer peripheral surface of an annular body 23. The locking jig 22 is fitted to the shaft portion 19b of the mandrel 19 whose outer peripheral surface is formed into the tapered surface 25.

A relative rotation preventing mechanism is provided between the locking jig 22 and the end surface 19c of the mandrel 19. This mechanism is composed of a pin hole 19d formed on the end surface 19c of the mandrel 19 and a pin 26 provided on the locking jig 22 side.

The locking jig 22 is the shaft portion 1 of the mandrel 19.
As shown in FIG. 2, the resin-impregnated reinforced fiber bundle is wound on the mandrel 19 and the locking jig 22 in a predetermined number of layers in a state in which the resin-impregnated reinforcing fiber bundle is attached to the 9b. The resin-impregnated reinforcing fiber bundle is locked by the needle-shaped body 24 of the locking jig 22 at the end of the mandrel 19, folded back in the locked state, and wound on the mandrel 19 as the next layer. Go. When the predetermined number of layers are wound, the locking jig 22 is heated and heated to cure the resin.

After heat curing, the FRP layer is separated at the portion A, and the separated FRP layer and the locking jig 22 are pulled out from the mandrel 19 and removed. Since the locking jig 22 and the shaft portion 19b of the mandrel 19 have a fitting structure with the tapered surface 25 interposed therebetween, the above removal can be easily performed even after heat curing.

Further, the locking jig 22 cannot be fixed only by the above-mentioned taper surface fitting structure, and the locking jig 22 is used as the mandrel 1.
When trying to rotate relative to 9, the pin 26
And the relative rotation prevention mechanism by the pin hole 19d works effectively,
The locking jig 22 is rotated integrally with the mandrel 19.
The relative rotation preventing mechanism is not limited to the above structure, and various known mechanisms such as a key and a key groove mechanism can be used. Further, when the relative rotation can be completely prevented only by the fitting by the tapered surface, this relative rotation prevention mechanism is not always necessary.

In the method shown in FIGS. 3 and 4, a tape-like locking jig 29 having a large number of needle-like bodies 28 fixed to the tape 27 as shown in FIG. 3 is prepared in advance. The tip of the needle-shaped body 28 projects from the tape end surface in the width direction of the tape 27.

As shown in FIG. 4, the tape-shaped locking jig 29 is wound around the outer peripheral surface of the end portion of the mandrel 19 so as to go around the outer peripheral surface for a predetermined length. In the state where the tape-shaped locking jig 29 is wound, the needle-shaped bodies 28 are arranged in the circumferential direction on the outer peripheral surface of the end surface of the mandrel 19, and the tips of the needle-shaped bodies 28 are separated from the end surface 19c of the mandrel 19. It projects toward the outside.

In this state, the resin-impregnated reinforced fiber bundle 12 is wound around the mandrel 19 in a predetermined number of layers as described above.
At the end of the mandrel 19, the resin-impregnated reinforced fiber bundle 12 is locked to the needle-shaped body 28 and folded back in a locked state. Then, when the winding of the predetermined number of layers is completed, the tape-shaped locking jig 29 is heated and hardened while being wound. After the heating and curing, the part in which the tape-shaped locking jig 29 is wound is separated.

In the production of the FRP tubular body as described above, the portion around which the locking means is wound is removed after being hardened by heating, so that the product FRP tubular body has uniform physical properties over the entire length. In addition, since the filament winding is performed while being locked by the locking means, the fiber at the end of the FRP tubular body to be molded is prevented from being disturbed before being heat-cured, and is maintained at a predetermined orientation angle, and That state is maintained even after heat curing. Therefore, it is possible to mold a uniform FRP tubular body having high strength and high elastic modulus.

In the above filament winding molding, when the resin-impregnated reinforcing fiber bundle 12 is wound around the mandrel 19, it is preferable to lower the temperature of the resin and increase its viscosity. If the viscosity of the resin is low, it is difficult to push out entrained voids (air bubbles), but by increasing the viscosity and winding it and applying pressure in the radial direction, the voids are easily discharged to the outside, and the quality is improved.

That is, the thermosetting resin generally has the characteristics shown in FIG. 5 in the uncured state.
When the resin is cured for molding, the temperature is raised to increase the viscosity as shown by arrow B, but in the above, the temperature is once lowered as shown by arrow C for void discharge.
It increases the viscosity. In order to lower the temperature, cold air may be blown to the resin-impregnated reinforcing fiber bundle 12 immediately before the winding around the mandrel. Further, cooling by pouring water is also possible.

In the filament winding molding method, since the resin-impregnated reinforcing fiber bundle 12 is wound around the mandrel 19 having a predetermined diameter, the formed FRP tubular body 21 is formed according to the inner diameter rule. In reality, the FRP tubular body 21 is often required so that the finished diameter of the outer diameter becomes a predetermined diameter. In order to achieve this, there is a method as shown in FIG.

That is, on the outer surface of the FRP tubular body 21 in the resin uncured state formed on the mandrel 19, a combination roller composed of a plurality of rollers 30 (three in the illustrated example) is provided respectively on the FRP tubular body 21. While being pressed in the radial direction on the surface of the FRP tubular body 21, the FRP tubular body 21 is caused to travel in the direction along the rotation axis. At this time, since the mandrel 19 and the FRP tubular body 21 are rotating in the direction of the arrow, in the circumferential direction of the FRP tubular body 21, between the outer surface of the FRP tubular body 21 and the surface of each roller 30. Slips. Each roller 30 has an arcuate surface corresponding to a target forming outer diameter (target finish diameter) of the FRP tubular body 21 when viewed in a cross section including its rotation axis.

By pressing the combination roller 30 in this manner, the resin of the uncured FRP tubular body 21 is squeezed, and by adjusting the pressing force and the number of times of traveling on the surface of the FRP tubular body 21, the outer diameter is adjusted. This allows for the formation of a law, and the target outer diameter finish dimension can be obtained accurately. Further, by the pressing of the roller 30, the voids that have been caught are discharged, and the strength of the molded FRP tubular body 21 is improved and the quality is improved.

The surface finish of the roller 30 may be either a mirror finish or a satin finish, but a satin finish is more preferable in that the cutting thread or the like is difficult to get onto the roller surface.

Further, as shown in FIG. 7, a ring 40 having an inner diameter corresponding to the target finishing diameter of the FRP tubular body 21.
Can also be made to travel integrally with the carriage stand 17, for example. The resin-impregnated reinforcing fiber bundle 12 is wound around the mandrel 19 while being in contact with the ring 40 while maintaining a predetermined angle. Resin impregnated reinforced fiber bundle 12
The resin is wound while being squeezed by the ring 40, and the entrainment of air is suppressed. Also,
When the outer diameter of the uncured FRP tubular body 21 that is being molded comes close to the target diameter, even if there is a portion that partially exceeds the target diameter, that portion is narrowed by the ring 40 and stored in the target diameter. Therefore, the outer diameter rule can be finally formed, and the target finish diameter can be accurately obtained.

[0043]

As described above, according to the present invention, the resin-impregnated reinforcing fiber bundle can be evenly wound up to the end of the mandrel at a predetermined winding angle without causing any disturbance by the locking means. By removing the engaging means winding portion after heat curing, the FRP tubular body to be the product has uniform physical properties over the entire length and can be made into a FRP tubular body with high strength and high elastic modulus. FRP that has become possible and has been finished to the desired accuracy up to the end
A tubular body can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an FRP tubular body manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 is a partially enlarged vertical cross-sectional view showing a state during molding of the mandrel and the FRP tubular body of the apparatus of FIG.

FIG. 3 is a perspective view of a tape-shaped locking jig.

FIG. 4 is a partial front view of the mandrel showing a state in which the tape-shaped locking jig is mounted on the mandrel in FIG.

FIG. 5 is a diagram showing a relationship between temperature and viscosity of an uncured thermosetting resin.

FIG. 6 is a schematic vertical cross-sectional view showing a preferable FRP tubular body forming method on a mandrel.

FIG. 7 is a partial schematic perspective view showing another preferable FRP tubular body forming method on a mandrel.

[Explanation of symbols]

 1 Creel Stand 2 Bobbin 3 Reinforcing Fiber Yarn 4 Reinforcing Fiber Bundle (Before Resin Impregnation) 5, 6a, 6b, 7a, 7b Separate Roll 8 Guide Roll 9 Resin Impregnation Bath 10 Resin 11a, 11b, 11c Roller 12 Resin Impregnation Reinforced Fiber Bundle 13 Guide Means 13a, 13b, 13c Guides 14, 14a, 14b Feed Rollers 15a, 15b Pads 16 Brackets 17 Carriage Stands 18 Cylinders 18a Hollows 19 Mandrels 19a Mandrel Rotation Shafts 19b Mandrel Shafts 19c Mandrel End Faces 19d Pin Holes 20 Rotation driving means 21 FRP tubular body 22 Locking jig 23 Annular body 24 Needle-like body 25 Tapered surface 26 Pins 27 Tape 28 Needle-like body 29 Tape-like locking jig 30 Roller 40 Ring

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area B29L 23:00

Claims (6)

[Claims] 1. When a reinforcing fiber bundle impregnated with a thermosetting resin is wound around a mandrel and then the resin is heat-cured to form an FRP tubular body, a resin-impregnated reinforcing fiber bundle is attached to the end of the mandrel. After attaching a locking means capable of locking and winding a resin-impregnated reinforcing fiber bundle with a predetermined number of layers on the mandrel, the resin is heat-cured while the locking means is wound,
A method of manufacturing a tubular body made of FRP, characterized in that the winding portion of the locking means is removed after heat curing. 2. An apparatus for forming a FRP tubular body by winding a reinforcing fiber bundle impregnated with a thermosetting resin around a mandrel and then heat-curing the resin to form an FRP tubular body,
FR, characterized in that locking means capable of locking the resin-impregnated reinforced fiber bundle is removably attached after the resin is heated and cured.
Device for manufacturing P tubular body. 3. The locking means comprises a locking jig in which a plurality of needle-shaped bodies are provided on an outer peripheral surface of an annular body, and the locking jig is fitted on a shaft portion of a mandrel. Item 2. The FRP tubular body manufacturing apparatus according to item 2. 4. The apparatus for manufacturing an FRP tubular body according to claim 3, wherein the outer peripheral surface of the shaft portion of the mandrel is formed into a tapered surface. 5. The FR according to claim 3, wherein a relative rotation preventing mechanism is provided between the locking jig and the mandrel.
Device for manufacturing P tubular body. 6. The locking means comprises a tape-shaped locking jig in which a large number of needle-shaped bodies are fixed to a tape, and the tape-shaped locking jig is attached to the end of the mandrel. The apparatus for manufacturing an FRP tubular body according to claim 2, wherein the portion is wound so as to project from the end surface of the mandrel.