JP2003292248A - Fiber bundle joining method and fiber bundle joining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiber bundle joining method capable of improving the strength of a joint portion when two flat fiber bundles made from long fibers are joined by the action of fluid. <P>SOLUTION: End portions of the two flat fiber bundles F made from a large number of long fibers are arranged to be superimposed each other. A superimposed part of each fiber bundle F is gripped by a gripping member 21 provided with a gripping portion gripping so as to intersect with a fiber arranging direction at three points at specified intervals. To each part of the fiber bundle F gripped by the gripping portion, compressed air is jetted from a jetting nozzle 30 relatively moving in a direction intersecting with the fiber arranging direction, thereby entangling the fibers. The jetting nozzle 30 is made to relatively make one or more round trip. The jetting pressure of the compressed air is increased at the time of returning of the jetting nozzle 30 rather than at the time of going. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining fiber bundles and a device for joining fiber bundles, and more specifically, for joining fiber bundles for joining end portions of two flat fiber bundles composed of many long fibers. The present invention relates to a method and a fiber bundle joining device.

[0002]

2. Description of the Related Art When a fiber-reinforced composite material is manufactured by a filament winding method, or when a three-dimensional fiber structure is used as a reinforcing material for the fiber-reinforced composite material, a method of arranging fiber bundles in an opened state from the beginning Are preferable in view of the physical properties of the composite material. Here, opening the fiber bundle means expanding the filaments constituting the fiber bundle to make the fiber bundle flat.

In the filament winding method or the method for manufacturing a three-dimensional fiber structure, since the fiber bundle is fed from the bobbin, before the fiber bundle wound on the bobbin is completely used up, the fiber bundle of the next bobbin is used. Need to be joined with. If the knot portion is provided to join the fiber bundles like a normal thread, the knot portion exists in the product without being opened, and the physical properties of the product deteriorate. Therefore, a method has been proposed in which the ends of the fiber bundle are joined together by entanglement of the fibers without providing a knot.

For example, in the joining method disclosed in Japanese Patent Application Laid-Open No. 2001-151418, two flat fiber bundles composed of long fibers without twisting are put into each fiber bundle with the end portions of the fiber bundles being overlapped. The bearings and the gripping members press the respective members at two positions with a predetermined interval in the fiber arrangement direction. Compressed air is sequentially ejected from the air ejection holes to a plurality of locations in a direction intersecting the fiber arrangement direction with respect to each fiber bundle between the pressed two locations to entangle adjacent fibers.

[0005]

[Problems to be Solved by the Invention]
In the joining method disclosed in 418, the end portions of two fiber bundles to be joined are overlapped with each other, and the fibers are entangled by the air jetted at a constant pressure from the air jet holes to entangle both fiber bundles. Since the fibers are joined together, the fiber bundle can be easily joined without providing a knot. However, depending on the material of the fiber bundle, the joining of the entangled portions may be released when a strong tension is applied to the entangled portions.

The present invention has been made in view of the above problems, and the first object thereof is to provide a flat fiber made of long fibers.
It is an object of the present invention to provide a method for joining fiber bundles that can further increase the strength of the joint when the fiber bundles of a book are joined by the action of a fluid. A second object is to provide a fiber bundle joining device suitable for carrying out the method.

[0007]

In order to achieve the first object, the method of the present invention according to claim 1 is such that end portions of two flat fiber bundles composed of a large number of long fibers to be joined to each other. Are arranged in a stacked state, and the overlapping portions of the fiber bundles are gripped at at least two positions with a predetermined interval by a gripping portion that grips the fiber bundle in a state intersecting with the arrangement direction of the fibers. Then, for each part of the fiber bundle gripped by the gripping part, a fluid is jetted from a jetting nozzle that relatively moves in a direction intersecting the fiber arrangement direction to entangle the fibers, and the jetting nozzle makes one or more reciprocations. Relative movement is made to increase the fluid injection pressure at the time of backward movement of the injection nozzle than at the time of forward movement.

In the present invention, the end portions of the fiber bundles to be joined are jetted with the fluid from the jet nozzles that relatively move in the direction intersecting the fiber arrangement direction to the portions that are held at a predetermined interval in the fiber arrangement direction. Then, due to the action of the fluid, the fibers are rotated about both grips as fulcrums and are entangled with each other. Unlike the prior art, the fluid ejection pressure is not constant, the ejection nozzle is relatively moved for one reciprocation or more, and the fluid ejection pressure is increased when the ejection nozzle moves backward rather than when the ejection nozzle moves forward. Therefore, the entanglement of the fibers becomes complicated and the strength of the joint increases.

According to a second aspect of the present invention, in the first aspect of the invention, the fluid ejection is performed in pulses when the ejection nozzle moves forward. According to the present invention, the entanglement of the fibers becomes complicated and the strength of the joint can be further increased, as compared with the case where the jet nozzle is relatively moved while continuously jetting the fluid from the jet nozzle.

According to a third aspect of the invention, in the first or second aspect of the invention, the relative moving speed of the injection nozzle is set to 5 mm / sec or less. In the present invention, the action of the fluid on the fibers is effectively performed, and the entanglement becomes complicated.

According to a fourth aspect of the invention, in the invention according to any one of the first to third aspects, the number of the grip portions is three or more. In the present invention, since the number of gripping portions is three or more, a plurality of pairs of entangled portions are formed in the longitudinal direction of the fiber bundle, and the strength is further improved.

According to a fifth aspect of the invention, in the invention according to any one of the first to fourth aspects, the fiber bundle is a fiber bundle of carbon fibers. Fiber bundles of carbon fibers are produced by a manufacturing method, for example, depending on the sizing agent and carbonization conditions used,
It may be difficult to obtain an entangled state with high bonding strength by simply injecting gas from the injection nozzle at a constant pressure for the fibers that form the fiber bundle. However, claims 1 to 4
According to the method of the invention described in any one of 1, the fibers are efficiently entangled, and the fiber bundles of carbon fibers can be bonded well.

In a sixth aspect of the present invention, the support portions for supporting the end portions of the flat fiber bundle are arranged in two or more places at predetermined intervals, and the support portions cooperate with each other. A gripping member that is moved by an actuator to a gripping position that grips the fiber bundle and a retracted position that releases the fiber bundle, and is relatively movable in a direction intersecting the fiber bundle supported by the support portion with respect to the base. A movable member provided and provided so as to be movable integrally with the movable member, and when the movable member relatively moves with respect to the base, faces the fiber bundle held by the support portion and the holding member. An injection nozzle arranged so as to move a position to move, an actuator capable of reciprocating the movable member and adjusting the moving speed,
A control valve for controlling the timing of fluid ejection from the ejection nozzle and a fluid pressure adjusting means capable of adjusting the fluid ejection pressure from the ejection nozzle are provided.

In the present invention, when the two fiber bundles are joined together, the end portions of the two fiber bundles to be joined are arranged so as to straddle between the support portions of the base and are arranged at the gripping position. The gripping member and the support portion hold the gripped state. In this state, the fluid is ejected from the ejection nozzle, and the movable member is moved relative to the base in the direction intersecting the fiber bundle by the action of the actuator. The moving speed of the movable member can be changed. The jet nozzle is moved integrally with the movable member in a direction intersecting the fiber arrangement direction while jetting the fluid, and the superposed fiber bundles are subjected to the action of the fluid while being held by the bearings and the holding member. The gripping portion is rotated about the fulcrum to be entangled. The fluid ejection timing from the ejection nozzle is controlled by the control valve, and the fluid ejection can be performed continuously or in a pulsed manner. Further, the fluid injection pressure from the injection nozzle can be adjusted by the fluid pressure adjusting means, and the injection pressure can be easily changed between the forward movement and the backward movement of the injection nozzle. Therefore, the fiber bundle joining device of the present invention can be applied to any of the methods of the invention described in claims 1 to 5.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS. First, the fiber bundle joining device will be described. In addition, in this embodiment, FIG.
4 and the right side is the front side of the fiber bundle joining device 11. As shown in FIGS. 3 to 6, the fiber bundle joining device 11 includes a base 12 and a movable member 13 arranged so as to be movable relative to the base 12. The base 12 is formed in a flat plate shape, and as shown in FIG. 5, supporting portions 14, 15R, 15 for supporting the end portion of the flat fiber bundle F on the front side thereof.
L, 16R, and 16L are arranged side by side in the left-right direction at two or more locations at predetermined intervals. That is, the end portions of the fiber bundle F to be joined are supported by the support portions 14, 15R, 15L, 16R, 16 while the fibers extend in the left-right direction of the fiber bundle joining device 11.
Supported by L. In this embodiment, the bearing portions 15R and 15L are arranged on both sides of the bearing portion 14 arranged in the center, and the bearing portions 16R and 16L are arranged outside the bearing portions 15R and 15L.

Each bearing 14, 15R, 15L, 16R,
Guide portions 14a, 15a, 16a for guiding the fiber bundle F so as to extend in the left-right direction of the fiber bundle joining device 11 are provided in 16L.
Of the fiber bundle F are provided at intervals with a width substantially equal to the width of the fiber bundle F. Grooves 14b, 15b, 16b for accommodating a part of a gripping member described later are formed in each of the guide portions 14a to 16a. Each bearing 14, 15R, 15L, 1
Elastic members (for example, rubber) are attached to the 6R and 16L at positions corresponding to the grooves 14b, 15b, and 16b, and the surfaces thereof form the gripping surfaces 14c, 15c, and 16c. Bearings 15R and 16R arranged on the right side with the bearing 14 in between.
And the bearing portions 15L and 16L arranged on the left side are provided at both ends of one block 17 and 18, respectively.
The gripping surfaces 16c of both bearings 16R and 16L are different from the other bearings 1
It is formed to be slightly higher than the gripping surfaces 14c, 15c of 4, 15R, 15L. Each block 17, 18 has a guide portion 17a continuous with the guide portions 15a, 16a,
18a is formed and the guide portions 17 facing each other are formed.
The surface between a and 18a is formed at the same height as the grip surface 15c.

A pair of support portions 19 are provided on the front side of the center of the base 12 in a protruding manner, and a support shaft 20 supported by the support portions 19 is attached to the support shaft 20.
A gripping member 21 that grips the fiber bundle F in cooperation with each of the support portions 14, 15R, 15L, 16R, 16L is rotatably supported. The gripping member 21 includes the support portions 14 and 15
The support plate 22 is provided with a gripping portion 22a that grips the fiber bundle F in cooperation with R, 15L, 16R, and 16L, and a support arm 23 that supports the support plate 22. The support arm 23 is supported at its tip. Supports the plate 22,
The base end is rotatably supported by the support shaft 20.

An air cylinder 24 as an actuator is provided near the rear end of the base 12 and has a piston rod 2
4a is fixed above the base 12 so as to extend in the front-rear direction. An intermediate portion of the support arm 23 is connected to the tip of the piston rod 24a via a connection shaft 25 that extends horizontally in a state orthogonal to the support arm 23. The connecting shaft 25 is fixed to the support arm 23 in a state of penetrating a vertically extending long hole formed at the tip of the piston rod 24a. Then, the support arm 23 is rotated by the operation of the air cylinder 24, and the gripping member 21 is moved to each of the support portions 1.
In cooperation with 4, 15R, 15L, 16R, 16L, the gripping position for gripping the fiber bundle F and the retracted position for releasing the fiber bundle F are moved. In this embodiment, the gripping member 21 is arranged at the gripping position while the piston rod 24a is arranged at the projecting position.
The gripping member 21 is placed in the retracted position with a being placed in the retracted position.

In this embodiment, the grip portion 22a is
Is not integrally formed with the support plate 22, and as shown in FIG. 7A, the gripping pieces 26a and 26b forming the gripping portion 22a are fixed to the support plate 2 by bolts (not shown).
It is formed by fixing to 2. The grip portion 22a corresponding to the support portion 14 is composed of a grip piece 26a.
Grip 22a and bearing 15 corresponding to 5R and 16R
The gripping portions 22a corresponding to L and 16L are respectively configured by gripping pieces 26b. The grip portion 22a corresponding to both the support portions 16R and 16L is formed to be slightly shorter than the grip portion 22a corresponding to the support portions 14, 15R and 15L. Each of the gripping pieces 26a and 26b has a groove 14b on both front and rear sides of its tip in a state where the gripping member 21 is arranged at the gripping position.
The fiber bundle F is grasped in the state of being accommodated in the spaces 16b to 16b. An elastic member (for example, rubber) is attached to the tip of each grip portion 22a, and when the grip member 21 is placed at the grip position, each support portion 14, 15R, 15L, 16R,
The fiber bundle F is gripped between the elastic member attached to 16L.

In the left block 18, a cylindrical nozzle 27 is provided near the gripping surface 15c of the support portion 15L and has a gripping surface 15c.
It is arranged so as to extend along. The nozzle 27 is formed in a circular arc shape so that substantially half of the nozzle 27 is located above the gripping surface 15c, and a plurality of holes 27a are arranged in a staggered pattern on the circular arc surface.

On the outside of each support portion 19, the base 12 is formed with a notch portion 28 that extends in the front-rear direction and is open at the front. On the bottom surface of the base 12,
A pair of guide rails 29 is fixed outside the notches 28 and extends in the front-rear direction.

The movable member 13 is formed in a substantially U-shape in plan view and is provided so as to be movable along a guide rail 29 fixed to the lower surface of the base 12. That is, the movable member 13
With respect to the base 12, the bearings 14, 15R, 15L,
The fiber bundles F supported by 16R and 16L are disposed so as to be relatively movable in a direction intersecting (orthogonal in this embodiment) the fiber bundle F.

The movable member 13 is provided with two injection nozzles 30 so that they can move integrally, and when the movable member 13 moves relative to the base 12, the support portions 14, 15R, 15 are provided.
L, 16R, 16L and the holding member 21 are arranged so as to move at a position facing the fiber bundle F held by the holding member 21.
More specifically, the support plate 31 is provided between the pair of arm portions 13a of the movable member 13 extending along the guide rail 29.
Are fixed in a state of extending in the left-right direction and perpendicularly to the lower surface of the arm portion 13a. Two support blocks 32 are fixed to the front surface of the support plate 31 at predetermined intervals, and the injection nozzle 30 is fixed to the support block 32. When the movable member 13 moves, the injection nozzle 30
The injection hole 30a (shown in FIG. 5) is movable so as to be movable substantially along the center between the bearings 14 and 15R and between the bearings 14 and 15L. It is fixed.

As shown in FIG. 3, the injection nozzle 30 is connected to a compressed air source C via a compressed air supply pipe 33, and a control for controlling the fluid injection timing from the injection nozzle 30 in the middle of the compressed air supply pipe 33. A valve 34 and a fluid pressure adjusting means 35 capable of adjusting the compressed air (fluid) injection pressure from the injection nozzle 30 are provided. The control valve 34, the fluid pressure adjusting means 35, etc. are omitted in FIG.

The base 12 is equipped with two air cylinders 36 and 37 as actuators capable of reciprocating the movable member 13 and adjusting the moving speed.
The first air cylinder 36 is fixed to a bracket 38 fixed to the center of the lower surface rear end of the base 12, and the second air cylinder 37 is fixed to a bracket 39 fixed to the center of the lower surface front end of the base 12; It is fixed so as to extend in the direction. The tip of the piston rod 36a of the first air cylinder 36 is fixed to the center of the rear surface of the support plate 31, and the tip of the piston rod 37a of the second air cylinder 37 is fixed to the center of the front surface of the support plate 31. There is. In this embodiment, the air cylinders 36 and 37 are arranged so that both piston rods 36a and 37a are located on a straight line.

The first air cylinder 36 is used when the movable member 13 is moved at a low speed, and the second air cylinder 37 is used.
Is for use when moving the movable member 13 at high speed. The first air cylinder 36 is connected to a low pressure compressed air source 41a via a pipe 40, and the second air cylinder 37 is connected to a high pressure compressed air source 41b via a pipe 42. When one of the air cylinders 36 and 37 is used, the other is in a free state. In this embodiment, the electromagnetic switching valves 43a and 43b for switching the positions of 4 ports and 3 positions are provided in the middle of the pipes 40 and 42.
Both of the electromagnetic switching valves 43a and 43b are configured such that the A port and the B port are in communication with each other when the spool is in the neutral position.

As shown in FIG. 3, when the movable member 13 is placed at the reference position, the movable member 13 is supported between the support portions 14 and 15R and between the support portions 14 and 15L. Gripping surface 1 of parts 14, 15R, 15L
A mounting portion 44 is provided slightly below 4c and 15c. As shown in FIG. 3 and FIG.
A shaft support portion 44a is projectingly provided at the base end of the first and second pressing members 4 with respect to the support shaft 45 supported by the shaft support portion 44a.
6, 47 are rotatably supported at their base ends. Both pressing members 46, 47 are supported by the supporting portions 14, 15R, 15L.
It is provided so as to be movable and arranged in an operation position where it can come into contact with the fiber bundle F supported by the support and a retracted position which allows the fiber bundle F to be arranged between the support portions 14, 15R, 15L.

The first pressing member 46 cooperates with the placing portion 44 to sandwich the first fiber bundle F below the holding surfaces 14c, 15c of the supporting portions 14, 15L, 15R. The second pressing member 47 cooperates with the first pressing member 46 to support the second fiber bundle F on the supporting portions 14, 15L, 15R.
The gripping surfaces 14c and 15c can be held at substantially the same height.

Next, the operation of the fiber bundle joining device 11 configured as described above will be described. 1 (a) to (d) and FIG.
(A)-(d) is a schematic perspective view which shows a joining procedure. In addition, in order to distinguish the two fiber bundles F to be joined in the drawing, the fiber bundle F is hatched. In addition, the grip member 21
The retracted position is actually lower than the position shown in FIGS. 1A to 1D, but since the pressing member 46 and the like are hidden when illustrated in this position, the retracted position is shown above the actual retracted position for convenience. ing.

When joining the fiber bundles F, first the movable member 1
In the state where 3 is arranged at the reference position, the gripping member 21 and both pressing members 46 and 47 are arranged at the retracted position as shown in FIG. In that state, as shown in FIG.
The first fiber bundle F is attached to the support portions 16L, 15L, 14, 15
After arranging it on both mounting portions 44 in a state of straddling R and 16R,
Both first pressing members 46 are arranged in the working position. Then, the first fiber bundle F is moved so that the end of the first fiber bundle F moves to the grip surface 15 of the block 18 as shown in FIG. 1C.
Place it so that it is on top of c. The end of the first fiber bundle F is located at the supporting portion 1 from the holding position by the supporting portion 15L and the holding portion 22a.
It is located on the 6L side and arranged to cover the nozzle 27.

Next, the second fiber bundle F is attached to the first pressing member 4
After being arranged so as to straddle the supporting portions 16L, 15L, 14, 15R, 16R on the position 6, the second pressing member 47 is arranged at the operating position. Then, by moving the second fiber bundle F,
As shown in FIG. 1D, the ends of the second fiber bundles F are arranged so as to face the gripping surface 15c of the block 17. When the bonded fiber bundle F is fed out through a fiber bundle supply head (not shown), the end portion of the first fiber bundle F is located in front of the end portion of the second fiber bundle F in the traveling direction.

Next, the air cylinder 24 is actuated to rotate the support arm 23 to dispose the gripping member 21 at the gripping position as shown by the solid line in FIGS. 2 (a) and 3. In this state, both fiber bundles F are pressed by the support plate 22 at four positions at predetermined intervals in the fiber arrangement direction, and the grip portion 2 is held.
It is gripped by 2a and the supporting portions 16L, 15L, 14, 15R, 16R.

Next, after the supply of compressed air to both injection nozzles 30 is started, the first air cylinder 36 is operated to project, and the movable member 13 is moved relative to the base 12. As a result, the movable member 13 is moved in the direction orthogonal to the fiber bundle F, and as shown in FIG.
The fiber bundle F gripped by 15L, 14, 15R, 16R and the grip member 21 is relatively moved toward a position facing the injection hole 30a. The relative moving speed of the ejection nozzle 30 was set to 5 mm / sec or less, for example, 2 mm / sec. The fiber bundle F is sandwiched by both the pressing members 46, 47 and the placing portion 44, but the clamping force is set by the both pressing members 46, 47.
Since the movable member 13 moves, the fiber bundle F smoothly escapes from between the pressing members 46 and 47 and the mounting portion 44.

Then, as shown in FIG. 2 (c), the injection hole 30a is moved so as to traverse below the fiber bundle F. As shown in FIGS. 2D and 3, when the injection hole 30a moves to a position opposite to the reference position with respect to the fiber bundle F, the operation of the air cylinder 36 is stopped and the movable member 13 is stopped.
The forward movement of is completed. In that state, both pressing members 46, 47
After arranging in the retracted position, the first air cylinder 36 is retracted to move the movable member 13 to the reference position side (return).
Let By the time the movable member 13 is returned to the reference position, the fiber bundle F is again subjected to the action of injecting compressed air, and the movable member 13
The joining of the fiber bundles F is completed in the state where is returned to the reference position.

The injection pressure of the compressed air from the injection nozzle 30 is adjusted so that the injection pressure becomes higher when the movable member 13 moves backward, that is, when the movable nozzle 13 moves backward, than when it moves backward. For example, the injection pressure during forward movement is set to 0.2 MPa, and the injection pressure during backward movement is set to 0.5 MPa.

Further, compressed air is jetted from the nozzle 27 when the movable member 13 returns. Then, the end portion of the first fiber bundle F located below the second fiber bundle F has the hole 27a.
It is blown up by the compressed air jetted from, and the end tip penetrates the second fiber bundle F and is exposed from the surface of the second fiber bundle F opposite to the surface facing the first fiber bundle F. It becomes a state.

After the returning movement of the movable member 13 is completed, the supply of compressed air from the nozzle 27 and the injection nozzle 30 is stopped. Then, the air cylinder 24 is operated to rotate the support arm 23 to move the holding member 21 to the retracted position, and then the fiber bundle F is supported by the support portions 16L, 15L, 14, 15.
A series of joining work is completed by separating from R and 16R.
Then, as shown in FIG. 9, a joint portion 49 having a plurality of pairs (two pairs in this embodiment) of the entangled portions 48 in the longitudinal direction of the fiber bundle F is formed.

Next, the action of the air blown from the jet holes 30a to entangle the fibers in the overlapping portion of the fiber bundle F is shown in FIGS.
Description will be given according to the schematic diagram of (d). In the figure, white circles and black circles respectively indicate a plurality of fiber aggregates that form the fiber bundle F. As described above, the overlapped portion of the two flat fiber bundles F is held in the state in which both ends thereof are gripped, and the injection region of the compressed air is set in the width direction of the fiber bundle F (left and right directions in FIGS. 8A to 8D). ) Pass from one end side in order. As shown in FIGS. 8 (b) and 8 (c), the fibers of the polymerized portion are subjected to the fiber-spreading action and the rotation action therebetween, and the fibers are entangled. The fibers are not entangled one by one, but are entangled as a unit to some extent. Since the fibers are rotated by the action of the jet airflow G with both grips as fulcrums, the fibers are basically entangled even in the entangled state, unlike the case where one end is rotated in a free state. They are arranged along the (fiber arrangement direction).

The fiber bundle F joined as described above is used as a reinforcing fiber of a fiber-reinforced composite material. For example, it is used for manufacturing an FRP pipe for a propeller shaft by a filament winding device. The FRP propeller shaft has a structure in which metal joints (yoke) that connect the FRP pipe to a drive shaft, a driven shaft, and the like are press-fitted and joined to both ends of the FRP pipe (for example, Japanese Unexamined Patent Publication (Kokai) 2
000-120649).

Fiber bundles F consisting of 70,000 carbon fiber filaments were joined together at their ends, and the fiber bundles F were actually arranged on the mandrel by a filament winding apparatus. Then, when the joint passes through the guide bar and the fiber bundle supply head existing on the way from the bobbin to the fiber bundle supply head, the fiber is wrapped around the guide bar, the thread is peeled off when the guide bar is passed, and the head is passed. At the time, the yarn was peeled off, and the presence or absence of curling of the fiber end when passing the head was examined. As a result, the winding of the fiber around the guide bar, the peeling of the yarn when passing the guide bar, and the peeling of the yarn when passing the head did not occur. In addition, the fiber bundle was smoothly supplied without curling of the fiber end when passing through the head.

Comparing the case where the jet flow of the compressed air is reciprocated once with respect to the fiber bundle F and the case where it is reciprocated two times, the entangled state at the joint portion is better when two reciprocations are performed. It became dense and the tensile strength was high. However, the tensile strength is 20k even when it is reciprocated once.
It was close to g, and sufficient strength was obtained by reciprocating once.
The tensile strength was measured by joining both ends of one fiber bundle into a ring shape, pulling the fiber bundle with a spring, and measuring the value when the joint portion was peeled off.

This embodiment has the following effects. (1) The ends of the two fiber bundles F to be joined are fluidized (compressed air) from the injection nozzle 30 that relatively moves in the direction intersecting the fiber arrangement direction, to the portion held at a predetermined interval in the fiber arrangement direction. ) Is jetted, and the fibers are rotated by the action of the fluid with the gripping portion 22a as a fulcrum to be entangled with each other.
Unlike the conventional case, the fluid ejection pressure is not constant, and the fluid ejection pressure is made higher when the ejection nozzle 30 moves backward than when it moves forward.
As a result, the entanglement of the fibers becomes complicated, and the strength of the joint increases.

(2) Since the relative moving speed of the injection nozzle 30 is set to 5 mm / sec or less, the action of the fluid (compressed air) on the fibers is effectively performed, the entanglement becomes complicated, and the strength of the joint is further improved. To do.

(3) Since the relative moving speed of the injection nozzle 30 is set to 2 mm / sec, the strength of the joint portion is further improved without prolonging the joining time. (4) The injection hole 30a reciprocates in the width direction of the fiber bundle F, and compresses from one end in the width direction with respect to the weight-matching portion (overlapping portion) of the fiber bundle F in order toward the opposite end portion. Since air acts, the fibers are efficiently opened and rotated. Further, as compared with a configuration in which the ejection nozzle 30 is fixed at a predetermined position and the fiber bundle F side is moved, or a configuration in which a large number of ejection nozzles or ejection holes are arranged in the width direction of the fiber bundle and sequentially ejected in a relay manner. Simpler configuration.

(5) Since the number of the grip portions 22a is three or more, the joint portion 49 has an entangled portion 48 in the longitudinal direction of the fiber bundle F.
Are formed in plural pairs (two pairs in this embodiment), and the strength is further improved.

(6) The fiber bundle F is a fiber bundle of carbon fibers. The fiber bundle of the carbon fiber is a entangled state with high bonding strength if the fibers constituting the fiber bundle are simply injected with a constant pressure of gas from the injection nozzle depending on the manufacturing method, for example, the amount of the sizing agent used and the carbonization conditions. Can be difficult to get. However, according to the method of the present invention, the entanglement of the fibers is efficiently performed, and the fiber bundle F of the carbon fibers can be satisfactorily joined.

(7) The surface of the first holding member 46 opposite to the surface facing the mounting portion 44 in the holding position is the gripping surface 14c of the bearings 14, 15L, 15R.
It is on the same plane as 15c. Therefore, the slack amount of the fiber bundle F located on the air injection side is set by the thickness of the first pressing member 46, and it becomes easy to set the slack amount to an appropriate value.

(8) Of the ends of the fibers of the joint 49 of the fiber bundle F, when passing through a fiber bundle supply head (not shown),
The ends of the fibers on the front side in the traveling direction are processed so as to penetrate through the opposing fiber bundle F and be exposed on the opposite side. If this treatment is not performed, when the joint portion 49 passes through the fiber bundle supply head, the ends of the fibers are caught by the fiber bundle supply head, and the fibers are sequentially ordered from the ends by the friction between the ends of the fibers and the fiber bundle supply head. There is a risk of turning over and peeling from the joint 49. However, since the above-mentioned treatment is performed, even if the end of the fiber is turned over, there is no fear that the end of the fiber bundle F will easily return to the end and be separated from the joint 49, and the physical properties of the composite material will be improved.

(9) When grasping the overlapping portion of the two fiber bundles F, the first fiber bundle F is sandwiched between the placing portion 44 and the first pressing member 46, and the ends thereof are positioned, The first holding member 46 and the second holding member 47 form the second fiber bundle F.
Hold and position the end. Therefore, the fiber bundle F
It becomes easy to dispose the end portion at a predetermined distance from the support portions 15R and 15L.

(10) Mounting portion 44 and both pressing members 4
Since the moving members 6 and 47 move together with the movable member 13, when the compressed air acts on the fiber bundle F in the gripped state, the placement unit 44
Also, the structure for retracting the pressing members 46, 47 to a position that does not adversely affect the action of the compressed air is simplified.

(11) Since the elastic members are attached to the tip of the grip portion 22a and the support portions 16L, 15L, 14, 15R, 16R, when the grip member 21 is placed at the grip position, the fiber bundle F Is reliably gripped.

(12) When an FRP pipe for a propeller shaft is manufactured by using a filament winding device using the fiber bundle F bonded by the above-mentioned bonding method, it is necessary even if the bonded portion exists in the product. Propeller shafts with excellent physical properties can be manufactured.

The embodiment is not limited to the above, but may be configured as follows, for example. The fluid may be ejected in pulses instead of continuously ejecting the fluid from the ejection nozzle 30. The pulse may be ejected in both the reciprocating movement and only one of them may be ejected in the pulse, but it is preferable to perform the fluid ejection in the pulse in the forward movement of the ejection nozzle 30. When the fluid ejection is performed in a pulsed manner, the fibers are likely to partially bite in the thickness direction of the fiber bundle F, so that the fibers are entangled as compared to the case where the ejection nozzle 30 is relatively moved while continuously ejecting the fluid. Is complicated, and the strength of the joint portion 49 can be further increased.

The relative movement direction of the injection nozzle 30 with respect to the fiber bundle F is not limited to the direction orthogonal to the fiber arrangement direction of the fiber bundle F, but may be the direction intersecting diagonally. The ejection nozzle 30 may be fixed and the fiber bundle F side may be moved.

The fluid ejected from the ejection nozzle 30 is not limited to gas such as compressed air, but may be liquid. If the compressed air is injected and compressed in the same manner, the movable member 13
The slower the moving speed of the jet nozzle 30, that is, the moving speed of the injection nozzle 30, tends to increase the strength of the joint portion. However, if it is too slow, the time required for the joint becomes long, and therefore 2 to 4 mm / s.
ec is preferable, and 2 mm / sec is more preferable.

○ The moving speed of the movable member 13 is 5 mm / s.
It may be faster than ec. The moving speed of the movable member 13 may be different between the forward movement and the backward movement. By changing the moving speed during forward movement and during backward movement, the action of compressed air becomes different,
Confounding becomes complicated. For example, by making the speed at the time of forward movement slower than the speed at the time of backward movement, the action of compressed air per unit time at the time of forward movement becomes stronger than that at the time of backward movement, and the entanglement in the thickness direction of the fiber bundle is It gets complicated.

Instead of providing the air cylinder 36 for low speed movement and the air cylinder 37 for high speed movement, one air cylinder is provided and low pressure compressed air is supplied to the air cylinder at low speed movement, It may be configured to supply high-pressure compressed air when moving at high speed. In this case, the moving speed may vary slightly due to the influence of the compressed air remaining in the pipe, but there is no problem.

A hydraulic cylinder or a solenoid may be used instead of the air cylinder 24 as an actuator for moving the grip member 21. As a configuration for moving the gripping member 21 between the gripping position and the retracted position, instead of rotating the support arm 23 of the gripping member 21, the open position of the gripping member 21 is set to a position vertically elevated from the gripping position, The gripping member 21 is attached to the support portion 14
It is also possible to adopt a configuration in which it is moved up and down in the direction perpendicular to the above.

○ Without slackening the first fiber bundle F, simply 2
The fibers may be entangled by injecting compressed air from the injecting nozzle 30 in a state where the end portions of the fiber bundles of the book are overlapped and the overlapping portion is grasped by the grasping portion 22a.

The first pressing member 46 for setting the slack amount of the first fiber bundle F by omitting the second pressing member 47
Only one may be provided. Further, both pressing members 46 and 47 may be omitted. However, in the case where both holding members 46 and 47 are not provided, the gripping by the gripping member 21 becomes difficult unless the length of the overlapping portion between the ends of the two fiber bundles F is increased.

The air cylinders 36 and 37 are used as the base 12
Instead of fixing the air cylinders 36 and 37 to the base 12, the air cylinders 36 and 37 may be fixed to a fixing member different from the base 12. The end of the fiber bundle F to be joined may be gripped at two points, and one jet nozzle 30 may reciprocate at a position facing the center of both grips.

The treatment of the ends of the fibers in the superposed portion of the fiber bundle F is not limited to the method of the above-mentioned embodiment, but may be performed according to Japanese Patent Laid-Open No. 2001-2001
The method described in 151418 may be adopted. That is, when the overlapping portion of the fiber bundle F and the fibers in the vicinity thereof are opened to expand the width by 50% or more, and the overlapping portion is joined in that state, the fiber bundle is supplied to the fiber bundle supply head. The fiber bundle F is folded in two so that the ends of the fibers on the front side in the traveling direction are on the inside. Then, in this state, compressed air is jetted from the jet nozzle 30 to the front side in the traveling direction from the end of the fiber, and a joining process (entanglement process) is performed.

The treatment of the ends of the fibers in the overlapping portion of the fiber bundle F does not necessarily have to be performed. In this case, the nozzle 2
7 can be omitted. ○ The tip of the grip portion 22a and the support portions 14, 15L, 15
The elastic members attached to R, 16L and 16R may be omitted.

The material of the fiber bundle is not limited to carbon fiber, and other fibers such as polyaramid and ultra high molecular weight polyethylene fiber may be used. The technical idea (invention) 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 5, the relative moving speed of the injection nozzle is set to different speeds during forward movement and during backward movement. (2) In the invention described in the above technical idea (1),
The relative movement speed of the injection nozzle is set such that the speed at the time of forward movement is slower than the speed at the time of backward movement.

(3) A fiber bundle having a joint portion joined by the joining method according to any one of claims 1 to 5 and the technical ideas (1) and (2). (4) A joint part in which at least two pairs of entangled parts are provided such that the distance between the entangled parts forming each pair is larger than the distance between adjacent entangled parts which are entangled parts belonging to different pairs. A fiber bundle having.

(5) In the fiber bundle of the invention described in the technical idea (4), the joint portion is any one of claims 1 to 5, the technical ideas (1) and (2). They are joined by the joining method according to the invention described in 1.

(6) A fiber-reinforced composite material using the fiber bundle of the invention described in any one of the above technical ideas (3) to (5) as a reinforcing fiber. (7) A propeller shaft provided with an FRP pipe manufactured by a filament winding method, using the fiber bundle of the invention described in any one of the above technical ideas (3) to (5) as a reinforcing fiber.

[0069]

As described in detail above, according to the joining method of the invention described in claims 1 to 5, when two flat fiber bundles made of long fibers are joined by the action of fluid, The strength of the joint can be further increased. The invention according to claim 6 is suitable for carrying out the method.

[Brief description of drawings]

FIG. 1A to FIG. 1D are schematic perspective views showing a fiber bundle joining procedure according to an embodiment.

2A to 2D are schematic perspective views showing a fiber bundle joining procedure.

FIG. 3 is a schematic side view of a fiber bundle joining device in which a movable member is arranged at a reference position.

FIG. 4 is a schematic side view of the fiber bundle joining device in a state where the forward movement of the movable member is completed.

FIG. 5 is a partially cutaway schematic plan view of the fiber bundle joining device.

FIG. 6 is a schematic front view of a fiber bundle joining device.

7A is a schematic front view of a holding member, and FIG. 7B is a schematic perspective view of a holding member.

FIG. 8A to FIG. 8D are schematic diagrams for explaining the bonding action of fiber bundles.

FIG. 9 is a schematic plan view showing a joint portion of a fiber bundle.

[Explanation of symbols]

F ... Fiber bundle, 12 ... Base, 13 ... Movable member, 14, 1
5L, 15R, 16L, 16R ... Bearing part, 21 ... Gripping member, 22a ... Gripping part, 24 ... Air cylinder as actuator, 30 ... Injection nozzle, 34 ... Control valve, 35 ...
Fluid pressure adjusting means 36, 37 ... Air cylinders as actuators.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4L036 AA01 MA04 MA33 PA42 PA46                       PA49                 4L056 CB16

Claims (6)

[Claims] 1. A state in which two flat fiber bundles made up of a large number of long fibers are arranged such that their ends to be joined are overlapped with each other, and the overlapped portion of each fiber bundle intersects the arrangement direction of the fibers. The fluid is ejected from the injection nozzle that is gripped at at least two positions with a predetermined interval by the gripping portion that is gripped, and that moves relative to each part of the fiber bundle gripped by the gripping portion in the direction intersecting the fiber arrangement direction. And a fiber bundle are entangled with each other, the jet nozzle is relatively moved for one or more reciprocations, and the fluid jet pressure is increased when the jet nozzle moves backward rather than forward. 2. The method for joining fiber bundles according to claim 1, wherein the fluid ejection is performed in a pulsed manner when the ejection nozzle moves forward. 3. The relative moving speed of the injection nozzle is 5 mm.
/ Sec or less, the method for joining fiber bundles according to claim 1 or 2. 4. The grip portion is provided at three or more places.
~ The method for joining fiber bundles according to claim 3. 5. The method for joining fiber bundles according to claim 1, wherein the fiber bundle is a fiber bundle of carbon fibers. 6. A base in which supporting portions for supporting the end portions of the flat fiber bundle are arranged at two or more positions at a predetermined interval, and a gripping position for gripping the fiber bundle in cooperation with each of the supporting portions. When,
A gripping member that is moved by an actuator to a retracted position that releases the fiber bundle; a movable member that is arranged so as to be movable relative to the base in a direction intersecting the fiber bundle supported by the support portion; It is provided so as to be movable integrally with the movable member, and when the movable member moves relative to the base, it is arranged so as to move at a position facing the fiber bundle held by the support portion and the holding member. An injection nozzle, an actuator capable of reciprocating the movable member and adjusting a moving speed thereof, a control valve controlling a fluid injection timing from the injection nozzle, and a fluid capable of adjusting a fluid injection pressure from the injection nozzle. A fiber bundle joining device including a pressure adjusting means.