JP2003001716A - Method for producing fiber-reinforced plastic pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an FRP pipe which can increase a fiber volume content and improve the rigidity and modulus of elasticity of the pipe. SOLUTION: After a laminated fiber layer 5 including a fiber layer in which a fiber bundle F impregnated with a resin is wound onto a mandrel to form an angle of 45 deg. or below to the axial direction of the mandrel is formed, a fiber bundle 6 not impregnated with the resin is wound onto the outermost layer to form the angle of about 90 deg., and the resin is cured. A ductile fiber bundle of polyester fibers is used as the fiber bundle 6 to be wound onto the outermost layer. The width of the fiber bundle 6 does not exceed the width of a fiber bundle F wound onto the inside.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art There is a filament winding method (FW method) as a method for efficiently manufacturing a pipe made of FRP. In the FW method, a product is generally manufactured by winding a resin-impregnated fiber around a mandrel and then curing the resin. The strength of the product manufactured by the FW method is greatly affected by the winding angle of the fibers (the angle between the arranged fibers and the axial direction of the mandrel) and the arrangement state of the fibers. Further, in the FW method, when the winding angle of the fiber is larger than 45 °, the fiber can be wound at a predetermined pitch even if the fiber is wound around the cylindrical mandrel. However, when the winding angle is 45 ° or less, the tightening force of the fiber becomes small, and it becomes difficult to wind the fiber at a predetermined winding angle and a predetermined pitch.

When manufacturing a FRP pipe having high rigidity, a fiber bundle in which a large number of thin fibers are bundled is used as a fiber. When the fiber bundle is wound with a small winding angle, the force for winding the fiber bundle around the mandrel is weak. As a result, it is difficult to arrange the fiber bundle in a cylindrical shape having a uniform thickness. In addition, air remains between the fibers or the amount of resin remains. In order to manufacture a highly rigid FRP pipe, the ratio of the fiber to the total volume of the FRP,
That is, it is necessary to increase the fiber volume content (hereinafter referred to as Vf). Further, when it is desired that the resonance frequency is high as in a propeller shaft of an automobile, V of the central portion of the cylinder is
The higher f is, the higher the elastic modulus is and the higher resonance frequency can be obtained.

Japanese Patent Laid-Open No. 8-290487 discloses FW
When forming a FRP cylinder by the method, a helical winding layer is provided on the inside and a circumferential winding layer (hoop winding layer) is formed on the outside thereof. The helical tension is applied to the winding tension of the resin-impregnated fiber bundle around the mandrel. A method of making the resin-impregnated fiber bundle larger than that of the resin-impregnated fiber bundle is disclosed. According to this method, when the resin-impregnated reinforcing fiber bundle forming the circumferential winding layer is wound on the outside of the helical winding layer, the voids existing between the layers of the helical winding layer are extruded to the outside, and Excess resin adhering to the reinforcing fibers is squeezed out and Vf
Will increase.

[0005]

However, Japanese Unexamined Patent Publication No. 8-
In the method disclosed in Japanese Patent No. 290487, since the reinforcing fiber bundle forming the circumferential winding layer is impregnated with resin in advance, the resin squeezed from the helical winding layer forms the circumferential winding layer. It becomes difficult to pass inside. As a result, V
It is difficult to raise f.

The present invention has been made in view of the above problems, and an object thereof is to increase Vf, and FR
It is an object of the present invention to provide a method for producing a fiber-reinforced plastic pipe capable of improving the rigidity and elastic modulus of the P pipe.

[0007]

In order to achieve the above object, according to the invention of claim 1, when a fiber reinforced plastic pipe is manufactured by a filament winding method, a fiber bundle impregnated with a resin is used as a mandrel. After forming a laminated fiber layer including a fiber layer wound around a mandrel so that the angle with respect to the axial direction of the resin is 45 ° or less, a fiber bundle in a state where the outermost layer is not impregnated with resin has an angle of 90 °. After wrapping in a state close to °, cure the resin.

According to the present invention, after the laminated fiber layer is formed on the mandrel by the impregnated fiber bundle, the fiber bundle in a state where the outermost layer is not impregnated with the resin has an angle with respect to the axial direction of the mandrel close to 90 °. Wrapped around. Therefore, when the fiber bundle is wound, the resin squeezed out from the fiber bundle of the inner layer easily passes through the fiber bundle forming the outermost layer, the Vf of the manufactured FRP pipe is improved, and the resin has high rigidity. , High resonance frequency.

According to a second aspect of the invention, in the first aspect of the invention, a ductile fiber bundle is used as the fiber bundle wound around the outermost layer. In this invention, since the fiber bundle wound around the outermost layer has ductility, when the fiber bundle is wound around the outermost layer in a state where tension is applied, after the winding of the fiber bundle is completed, the resin bundle is squeezed out by contraction of the fiber bundle. The action continues and Vf can be further improved.

In the invention according to claim 3, in the invention according to claim 1 or 2, the fiber bundle wound around the outermost layer has a width equal to or smaller than that of the fiber bundle wound inside. Is used. In this invention, since the width of the fiber bundle wound on the outermost layer is equal to or less than that of the fiber bundle wound on the inner side, even when wound with the same winding tension, the fiber bundle having a wider width than the fiber bundle wound on the inner side. The resin squeezing effect is improved as compared with the case of winding.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is embodied in an FRP pipe for a propeller shaft is shown in FIGS.
It will be described with reference to FIG.

As shown in FIG. 1 (a), the FRP pipe 1 has a thick connecting portion 1b into which a base end of a yoke 2 (shown in FIG. 5) is inserted at both ends of a main body portion 1a. There is. F
Carbon fiber is used as the reinforcing fiber of the RP pipe 1, and epoxy resin is used as the matrix resin. The connecting portion 1b has the smallest wall thickness on the main body portion 1a side,
Tapered portion 1 formed so as to become thicker toward the end side
It has c.

FIG. 1 (b) is a partial schematic enlarged sectional view in the vicinity of the coupling portion 1b. However, hatching of each part is omitted in FIG. As shown in FIG. 1 (b), the reinforcing fibers of the FRP pipe 1 are helically wound at a predetermined equal pitch so that the angle (winding angle) with the axial direction of the pipe is a predetermined angle. A laminated fiber layer 5 composed of the winding layer 3 and the hoop winding layer 4 having a winding angle close to 90 ° is formed. The winding angle of the helical winding layer 3 is set to a predetermined value of 45 ° or less in order to satisfy the characteristics such as bending, twisting, vibration, etc., which are required when the helical winding layer 3 is assembled and used in a vehicle. In this embodiment, the winding angle is set to about ± 10 °. The hoop winding layer 4 is formed only on the connecting portion 1b of the FRP pipe 1, and is arranged so as to be sandwiched between the helical winding layers 3. Strictly speaking, the tapered portion 1c has a shape in which stepped portions are continuous.

The outermost layer of the FRP pipe 1 is formed with an outermost hoop winding layer 7 around which the fiber bundle 6 is wound in a state where the winding angle with respect to the axial direction of the pipe is close to 90 °. The outermost hoop winding layer 7 is formed by winding the fiber bundle 6 which is not impregnated with resin. In this embodiment, a ductile fiber bundle is used as the fiber bundle 6, and an organic fiber yarn (for example, polyester yarn) is used for the fiber bundle 6. Polyester yarn is composed of many filaments and becomes flat when wound.
A fiber bundle 6 having a width equal to or smaller than that of the fiber bundle F of the helical winding layer 3 or the hoop winding layer 4 wound inside the FRP pipe 1 is used. In this embodiment, the fiber bundle 6 has a thickness having a width of about 1/3 of the fiber bundle F in a wound state.

The FRP pipe 1 is formed by the filament winding method. As shown in FIG. 2, a filament winding machine (hereinafter referred to as FW machine) 11
Is provided with a pair of support brackets 13 and 14 disposed on the base plate 12, and the support brackets 13 and 14 include a rotating shaft 15 extending in the longitudinal direction of the base plate 12.
Equipped with 16. Chucks 18, 19 supporting the shaft 17a of the mandrel 17 are provided at the tips of the rotary shafts 15, 16.
Is provided. The first support bracket 13 is fixed to the base plate 12, and the second support bracket 14 is fixed on a support plate 21 movable along the longitudinal direction of the base plate 12 by the operation of the cylinder 20.

A motor 22 capable of forward and reverse rotation driving is fixed on the base plate 12, a belt transmission mechanism 23 is provided between the drive shaft of the motor 22 and the rotating shaft 15, and the rotating shaft 15 is driven by driving the motor 22. It is designed to be rotated in a predetermined direction.

The base plate 12 includes a support plate 21.
On the opposite side of the motor 22, a first actuator 24 is arranged so as to extend along the longitudinal direction of the base plate 12. A ball screw is used for the first actuator 24, and a known actuator having a structure for moving a movable body that can move integrally with the nut in one axial direction is used. The second actuator 2 provided with the fiber supply head 25 for guiding the resin-impregnated fiber bundle F on the moving body 24a mounted on the first actuator 24.
6 are provided.

The second actuator 26 is a moving body 24a.
An air cylinder 27 fixed above is arranged so as to be movable between a raised position and a reference position. The second actuator 26 holds the fiber feed head 25 at a position orthogonal to the peripheral surface of the mandrel 17 at the reference position, and when the fiber feed head 25 is placed at the raised position, the fiber feed head 25 moves at the mandrel 17 side.
It is designed to be held in a position extending in the tangential direction on the upper part of the peripheral surface. The second actuator 26 is fixed so as to move the fiber supply head 25 in a direction (front-back direction) orthogonal to the longitudinal direction of the base plate 12.

The motor 22 and the first actuator 24
Are driven by the control device C in a synchronized state. Then, by adjusting the rotation speed of the rotating shaft 15 and the moving speed of the fiber supply head 25, the fiber bundle F fed from the fiber supply head 25 is set on the mandrel 17 with an arbitrary winding angle. It can be wrapped around.

A resin tank 28 and a bobbin 29 are arranged on the side of the base plate 12, that is, on the side opposite to the motor 22 with respect to the first actuator 24. The resin tank 28 is attached to the fiber bundle F as the reinforcing fiber fed from the bobbin 29.
After being impregnated with the resin in, it is guided to the fiber supply head 25. The bobbin 29 is integrally rotatably supported by a shaft driven by a motor (not shown). Then, the fiber bundle F sent from the bobbin 29 by driving the motor is supplied to the fiber supply head 25 in a state where the tension acting on the fiber bundle F is adjusted to a predetermined range by a tension adjusting device (not shown). It has become.

The mandrel 17 has shafts 17a protruding from both ends of a mandrel main body 17b made of a metal cylinder, and restriction rings 30 are fixed to both ends of the mandrel main body 17b so as to be integrally rotatable with and removable from the mandrel main body 17b. There is. Pins 31 are detachably provided on the restriction ring 30 at equal pitches along the circumferential direction.

Next, a method of manufacturing the FRP pipe 1 using the FW machine 11 and the mandrel 17 configured as described above will be described. First, the mandrel 17 is set between the chucks 18 and 19, and then the tip of the fiber bundle F connected to the fiber supply head 25 is fixed to the restriction ring 30 to complete the preparation for manufacturing. At this time, the fiber supply head 25
Are arranged at positions corresponding to the restriction ring 30.

Next, the FW machine 11 is operated, the mandrel 17 is rotated in a fixed direction by the motor 22, and the fiber feeding head 25 is reciprocated along the longitudinal direction of the mandrel 17 by the first actuator 24. Then, the fiber bundle F sequentially fed from the bobbin 29 and impregnated with the resin in the resin tank 28 is wound around the mandrel 17 via the fiber supply head 25. The fiber bundle F is pulled out from the fiber supply head 25 while being impregnated with resin.

After passing between the pins 31, the fiber bundle F is wound around the shaft 17a and arranged so as to be folded back. The angle between the pins 31 located at both ends of the mandrel 17 and the axial direction of the mandrel 17 (winding). The fiber layer is formed on the mandrel 17 by being wound so that the attachment angle) becomes a predetermined angle.

First, after the fiber bundle F is wound by helical winding until the number of fiber layers reaches a predetermined number to form the helical winding layer 3, thick portions are formed at positions corresponding to the connecting portions 1b on both sides. Therefore, the hoop winding layer 4 is formed to have a predetermined thickness. As shown in FIG. 1B, the connecting portion 1b
Has the number of layers so that it has a tapered portion 1c.
At the position corresponding to c, it is formed so as to gradually decrease toward the main body 1a side. Next, the fiber bundle F is wound again over the entire length of the mandrel 17 by helical winding to form the helical winding layer 3, and the winding of the resin-impregnated fiber bundle F is completed, and the laminated fiber layer 5 is formed. It

Next, the organic fibers 8 are wound on the laminated fiber layer 5 as a fiber bundle 6 in a state where the winding angle is close to 90 ° and not impregnated with resin. Organic fiber 8
The fiber feeding head 25 of the FW machine 11 is used for winding the fiber, and as shown in FIG. 4, the organic fiber 8 fed from the bobbin 32 passes through the guide roller 33 and the fiber feeding head 25.
Be led to. Spindle supporting bobbin 32 (not shown)
Has a predetermined frictional resistance provided by the action of a permanent magnet provided between the shaft and a bearing that rotatably supports the support shaft. Then, a predetermined tension is applied to the organic fiber 8 pulled out from the bobbin 32, so that the tension of the organic fiber 8 can be adjusted. When the organic fiber 8 is wound, the second actuator 26 is arranged at the raised position, and the organic fiber 8 is supplied in a state of extending in the tangential direction with respect to the peripheral surface of the laminated fiber layer 5. In FIG. 4, the ratio of the sizes of the mandrel 17 and the actuators 24, 26, etc. is shown in a state different from that in FIG. Note that a dedicated yarn supply head may be used instead of using the fiber supply head 25 when winding the organic fiber 8.

As shown in FIG. 3, the organic fibers 8 are sequentially wound from the end of the mandrel 17 so as to tighten the laminated fiber layer 5 wound on the mandrel 17. By winding the organic fibers 8 in order from the end, the excess resin of the resin impregnated in the fiber bundle F of the laminated fiber layer 5 is squeezed out and the air existing between the fibers is removed (defoamed). The tension at the time of winding the organic fiber 8 is adjusted by a tension adjusting device and is set to, for example, about 9.8 to 49 MPa. In FIG. 3, the organic fibers 8 are illustrated as being wound at intervals, but in reality, the organic fibers 8 are wound in a state of substantially contacting each other.

After one layer of the organic fiber 8 is wound, the mandrel 17 is removed from the chucks 18 and 19 and the pin 31 is removed from the restriction ring 30. It is put in and the resin is cured at a predetermined temperature. The curing temperature varies depending on the resin, but is about 180 ° C. in the case of epoxy resin, for example. The FRP pipe 1 is formed on the mandrel 17 by heat curing. After cooling, the both ends of the FRP pipe 1 are cut inside the row of the traces of the pin 31 and the restriction ring 30 and the FRP pipe 1 are removed from the mandrel 17.

Thereafter, as shown in FIG. 5, the serrations 2a formed at the base end of the yoke 2 are press-fitted into both joints 1b (only one side is shown in FIG. 5) of the FRP pipe 1,
The yoke 2 is joined to the FRP pipe 1 to form the propeller shaft 9 of the automobile. The yoke 2 is formed with a hole 2b for mounting a universal joint (for example, a cross joint). The outer diameter of the base end of the yoke 2 is formed to be slightly larger than the inner diameter of the connecting portion 1b of the FRP pipe 1, so that the connecting portion 1b can be pressed into the connecting portion 1b.
The force to expand the outer layer acts on the outer side, but the presence of the hoop winding layer 4 ensures the strength.

This embodiment has the following effects. (1) When the FRP pipe 1 is manufactured by the FW method, the resin-impregnated fiber bundle F is wound around the mandrel 17 to form the laminated fiber layer 5, and then the outermost layer is not impregnated with the resin. The fiber bundle 6 is wound in a state where the angle with respect to the axial direction of the mandrel 17 is close to 90 °. Therefore, when the fiber bundle 6 is wound, the resin squeezed out of the fiber bundle F of the inner layer easily passes through the fiber bundle 6 forming the outermost layer, and the Vf of the manufactured FRP pipe 1 is improved and high. It has rigidity and has a high resonance frequency.

(2) Since a fiber bundle having ductility is used as the fiber bundle 6 wound around the outermost layer, when the fiber bundle 6 is wound around the outermost layer in a tensioned state, the winding of the fiber bundle 6 is completed. After that, the resin squeezing action continues and Vf
Can be further improved.

(3) Since the organic fiber is used as the ductile fiber bundle 6, the resin forms the outermost hoop winding layer 7 in comparison with the case where the inorganic fiber such as carbon fiber is used. 6 easily passes, the resin squeezing action is improved, and Vf is easily increased.

(4) Since organic fibers having heat shrinkability (for example, polyester fibers) are used as the ductile fiber bundles 6, the effect of increasing Vf by shrinking the organic fibers 8 during heat curing of the matrix resin is obtained. To be demonstrated
High Vf even when the tension when winding the organic fiber 8 is small
The FRP pipe 1 can be obtained.

(5) As the fiber bundle 6 wound around the outermost layer, a fiber bundle having a width equal to or smaller than that of the fiber bundle F wound inside is used. Therefore, even when wound with the same winding tension, the fiber bundle F wound inside is wound.
The resin squeezing effect is improved as compared with the case of winding a fiber bundle having a wider width.

(6) As the fiber bundle 6 wound around the outermost layer, a fiber bundle having a width about 1/3 of the fiber bundle F wound inside is used. Therefore, the resin squeezing effect is further improved as compared with the case where the fiber bundle 6 having the same width is wound.

(7) Since the connecting portions 1b are formed at both ends of the FRP pipe 1, it can be effectively used as a pipe used by being connected to a connecting member at both ends, for example, a propeller shaft 9 having desired physical properties. .

The embodiment is not limited to the above, but may be embodied as follows, for example. The width of the fiber bundle 6 not impregnated with the resin is not limited to about 1/3 of the width of the fiber bundle F wound inside, but as shown in FIG. Same as
As shown in FIG. 6B, the width may be wider than the fiber bundle F. However, if the width is wider than the fiber bundle F, the tightening failure may occur in the step portion of the tapered portion 1c. Therefore, the width of the fiber bundle 6 is preferably equal to or smaller than the width of the fiber bundle F.

When the organic fiber 8 is wound after the laminated fiber layer 5 is formed by the resin-impregnated fiber bundle F,
A plurality of organic fibers 8 may be wound around the mandrel 17 at the same time. The organic fibers 8 are simultaneously wound around the laminated fiber layer 5 in a state where the position of the mandrel 17 in the longitudinal direction is shifted and the winding angle is close to 90 °. In addition, each organic fiber 8 is wound around the laminated fiber layer 5 in a state in which the phase is shifted in the circumferential direction of the mandrel 17, that is, the contact position with respect to the laminated fiber layer 5 is shifted in the circumferential direction. Each organic fiber 8 is wound in order from the end at an integer multiple of the pitch when one organic fiber 8 is wound, more specifically, a pitch multiple times the number of the organic fibers 8 used, and the outermost hoop winding layer 7 is wound. Form.

In this case, since a plurality of organic fibers 8 are wound at the same time, the time required for winding is significantly less than half as compared to forming the outermost hoop winding layer 7 with one organic fiber 8. Can be shortened to In addition, since each organic fiber 8 is wound in the state in which the phase is shifted in the circumferential direction of the mandrel 17, the structure of the yarn feeding head is simpler than that in the case where the winding is performed in the state in which the phase in the circumferential direction is the same. It is possible to prevent the organic fibers 8 from interfering with each other. Further, the resin squeezing effect is increased.

By changing the tension at the time of winding the fiber bundle 6, the squeezing amount of the resin impregnated in the laminated fiber layer 5 is adjusted to set the Vf value of the FRP pipe 1 to a desired value. You may set it.

When winding the fiber bundle 6, the connecting portion 1b
The winding tension at 1 may be adjusted to be smaller than the winding tension at the main body portion 1a so that Vf of the main body portion 1a becomes larger than Vf of the coupling portion 1b. When it is desired that the resonance frequency is high as in the propeller shaft 9, the higher the Vf of the central portion of the shaft is, the higher the elastic modulus of the shaft is, and the higher resonance frequency can be obtained. Also, F
When the RP pipe 1 is used as the propeller shaft 9, a torsion torque is applied to the connecting portion 1b of the FRP pipe 1. At that time, the connecting portion 1b and the connecting portion 1b and the main body portion 1a
If the amount of resin near the boundary between and is small, delamination of the reinforcing fibers may occur. However, in order to secure the required amount of resin in the joint portion 1b, Vf of the FRP pipe 1 is set to the main body portion 1
By setting different values for a and the joint portion 1b side, a necessary resin amount is secured on the joint portion 1b side, and a necessary elastic modulus etc. is secured on the main body portion 1a.

○ The hoop winding layer 4 formed on the joint portion 1b
The position of is not limited to the position sandwiched by the helical winding layers 3, but may be formed in the innermost layer and the helical winding layer 3 may be arranged outside thereof. Further, the hoop winding layer 4 is divided into a plurality (for example, two), and the helical winding layer 3 in the coupling portion 1b is correspondingly divided.
It is also possible to increase the number of the above and arrange each hoop winding layer 4 so as to be sandwiched between the helical winding layers 3.

The inorganic fiber such as carbon fiber having no ductility may be used in place of the organic fiber 8 as the fiber bundle 6 not impregnated with the resin. However, since the ductile fibers continue to squeeze out the resin from the fiber bundles F in the inner layer even after the winding of the fiber bundles 6 is completed, Vf can be increased.

As the fiber bundle 6 not impregnated with resin,
The same fiber bundle F wound inside may be used without being impregnated with resin. In this case, after the laminated fiber layer 5 is formed, the fiber bundle F is placed in the resin tank 28 without replacing the bobbin 29.
By winding the fiber bundle 6 without passing through it, the work can be simplified because the fiber bundle 6 can be wound.

As the organic fiber 8, nylon 66 fiber or nylon 6 fiber may be used instead of the polyester fiber. Also in this case, since it has heat shrinkability, the same effect as that of polyester fiber can be obtained.

The absolute value of the winding angle of the fiber bundle F wound around the mandrel 17 does not have to be the same in all layers, and the winding angle may be changed for each layer. As the matrix resin, not only the epoxy resin but also another thermosetting resin (for example, polyimide resin), a thermoplastic resin having a high flexural modulus (for example, polyether ether ketone), or the like may be used. However, when forming the propeller shaft 9, an epoxy resin is preferable in terms of cost and required performance.

It may be applied to manufacture of pipes for drive shafts other than the propeller shaft 9. If the rotation speed is slow, or if the required performance such as torsional rigidity, heat resistance, and humidity resistance is lower than that of the propeller shaft of the vehicle, the glass fiber or aramid fiber may be mixed with the carbon fiber as the reinforcing fiber, or Glass fiber or aramid fiber may be used alone. Further, as the combination of the fiber and the matrix resin constituting the FRP, a combination of carbon fiber and vinyl ester resin, carbon fiber and phenol resin, etc. may be adopted. In this case, the cost of the resin is lower than that of the epoxy resin, so that the cost can be reduced.

Not limited to the drive shaft, it may be applied to any FRP pipe used by being connected to another connecting member at the end, for example, a drum of a rotary press. Also,
FR used by being connected to other connecting members at both ends
Not only P pipes, but also FRP pipes that are used by being joined to other connecting members only at one end, or FRP pipes that have bending force, tensile force, or compression force acting through the connecting portions. It may be applied to pipes.

The shape of the FRP pipe 1 is not limited to the circular cross section, and the reinforced fiber or the organic fiber 8 by the FW machine 11 can be used.
May have an elliptical cross section as long as it can be wound with a substantially constant tension when it is wound at a winding angle of about 90 °.

The connection between the FRP pipe 1 and the yoke 2 or other connecting member is not limited to the connection by press-fitting serrations, but may be an adhesive. A UV curable resin may be used as the matrix resin instead of the thermosetting resin.

The invention (technical idea) that can be understood from the above-described embodiment will be described below. (1) In the invention according to any one of claims 1 to 3, in the FRP pipe, at least one end of a main body is formed with a thick connecting portion into which a base end of a joint is inserted. There is.

(2) In the invention according to any one of claims 1 to 3 and (1), carbon fiber is used as the fiber bundle impregnated with the resin, and epoxy resin is used as the matrix resin. Has been done.

(3) In the invention described in (1), as the fiber bundle not impregnated with the resin, the same fiber bundle wound inside is used without being impregnated with the resin. (4) In the invention according to claim 2, the ductile fiber bundle is an organic fiber having heat shrinkability.

[0054]

As described in detail above, according to the inventions of claims 1 to 3, the fiber volume content can be increased and the rigidity and elastic modulus of the FRP pipe can be improved. it can.

[Brief description of drawings]

FIG. 1A is a schematic front view of an embodiment, and FIG.
Is a partial schematic enlarged cross-sectional view of the vicinity of the joint.

FIG. 2 is a schematic perspective view of a filament winding device.

FIG. 3 is a schematic perspective view when winding the organic fiber.

FIG. 4 is a schematic side view at the time of winding the organic fiber.

FIG. 5 is a partial sectional view of a propeller shaft.

6A and 6B are partial cross-sectional views of an FRP pipe according to another embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... FRP pipe, 3 ... Helical winding layer as a fiber layer, 4 ... Hoop winding layer, 5 ... Laminated fiber layer, 6 ... Fiber bundle not impregnated with resin, 8 ... Organic fiber, 17
… Mandrels, F… Fiber bundles.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasumi Miyashita             2-1, Toyota-cho, Kariya City, Aichi Stock Association             Company Toyota Loom Works (72) Inventor Yoshiharu Yasui             2-1, Toyota-cho, Kariya City, Aichi Stock Association             Company Toyota Loom Works F-term (reference) 3H111 AA01 BA15 BA25 BA28 CB08                       CB14 CC13 DA07 DA26 EA17                 4F205 AA36 AA39 AD16 AG08 AH17                       HA02 HA23 HA33 HA45 HB01                       HF05 HL02 HL14 HT13

Claims (3)

[Claims] 1. When a fiber-reinforced plastic pipe is manufactured by a filament winding method, a resin-impregnated fiber bundle is wound around a mandrel so that the angle with respect to the axial direction of the mandrel is 45 ° or less. After forming the laminated fiber layer including the layers, the outermost layer is not impregnated with resin, and the angle is 90 °.
A method for manufacturing a fiber-reinforced plastic pipe, in which the resin is hardened after being wound in a state close to the above. 2. The method for producing a fiber-reinforced plastic pipe according to claim 1, wherein a fiber bundle having ductility is used as the fiber bundle wound around the outermost layer. 3. A fiber bundle wound around the outermost layer,
The method for producing a fiber-reinforced plastic pipe according to claim 1 or 2, wherein a fiber bundle having a width equal to or smaller than that of the fiber bundle wound inside is used.