JPH11241256A - Three-dimensional fibrous structure and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a three-dimensional fibrous structure with improved adhesion to another composite material, and suitable as a structural material for a composite material well prevented from stress concentration at the joint. SOLUTION: This three-dimensional fibrous structure W is tapered on one side. It is composed of yarn layers, running in parallel to each other, of first in-plane yarns (x) arranged to turn up at an orientation angle of 0 deg., second in-plane yarns (y) arranged to turn up at an orientation angle of 90 deg., and biased yarns B1 and B2 arranged to turn up at an orientation angle of +90 deg. and -90 deg., respectively. Yarns (z) running in the thickness direction are arranged to cross the above yarns at right angles and connected to them while held by falling-out preventing yarns P. The positions at which the yarns (x), (y), B1 and B2 turn up are set in such a way that each yarn type accounts for a given ratio in the structure W, irrespective of its thickness. The yarn layer forming the outermost layer on the slanted side of the tapered section T is made of the biased yarns B1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a three-dimensional fiber structure and a method for producing the same.

[0002]

2. Description of the Related Art Fiber reinforced composites (FRP composites) are widely used as lightweight structural materials. There is a three-dimensional woven fabric (three-dimensional fiber structure) as a reinforcing base material for a composite material. A composite material using this three-dimensional fabric as a skeleton material and a resin or an inorganic material as a matrix is expected to be widely used as a structural material for rockets, aircraft, automobiles, ships, and buildings.

However, producing a large-sized and complex-shaped fiber-reinforced composite material using one three-dimensional fiber structure as a skeleton material is difficult and time-consuming to produce a three-dimensional fiber structure. Therefore, it is conceivable to use a structure material having a simple two-dimensional structure or a three-dimensional fiber structure as a skeleton material and a structure material having a three-dimensional fiber structure as a skeleton material by bonding them together.
On the other hand, it is known that the shape of the joint portion of the fiber reinforced composite material has a great effect on the stress concentration at the joint portion during the adhesive bonding of the fiber reinforced composite material (composite material engineering (Nikkagiren)) 841 and 845). And FIG.
As shown in FIG. 16A, as shown in FIG. 16B, the plate 71 having a certain thickness and one end thereof are formed in an inclined shape (tapered shape) as compared with the case where the plate members 71 having a certain thickness are joined to each other. 16 (c), the stress concentration is less likely to occur when the plate members 72 each having one end formed with an oblique shape are joined to each other. Further, when the plate members 71 having a constant thickness are joined together, increasing the lap length L of the bonding surface hardly contributes to the adhesive performance (withstand load), but the plate members 72 each having one end formed in an inclined shape are joined. In this case, the bonding ability is improved by increasing the wrap length L of the bonding surface. Therefore, by using a structural material having a three-dimensional fiber structure having one end formed in a tapered shape as a skeleton material, the characteristics (strength, stress concentration, and the like) of the joining portion (joining portion) are excellent. Large structural materials can be obtained.

Conventionally, as a method of manufacturing a three-dimensional woven fabric having a sequentially changing thickness, for example, Japanese Patent Application Laid-Open No. 2-191743 discloses a method shown in FIG. In this method, a step of inserting a weft yarn Y in a state perpendicular to the warp X between rows of the warp X group stretched in a plurality of rows and a plurality of columns corresponding to the cross-sectional shape of the three-dimensional woven fabric; And a step of inserting a vertical yarn (thickness direction yarn) Z in a state perpendicular to the warp X and the weft Y. Then, the number of rows into which weft yarns Y are inserted during weaving is reduced, and the thickness of the three-dimensional fabric is gradually reduced. In addition, the number of rows into which the weft yarns Y are inserted is reduced, and the warp yarns X on the surface layer are cut from the middle to gradually reduce the thickness of the three-dimensional fabric.

[0005] JP-A-1-221559 discloses a three-dimensional woven fabric having an irregular cross section. As shown in FIG. 18, the three-dimensional woven fabric W has a plurality of longitudinal yarns (warp yarns) X arranged corresponding to the cross section of the three-dimensional woven fabric W and an arrangement width of the longitudinal yarns X. The three-dimensional fabric W is provided with a width direction yarn (weft) Y arranged in the width direction and a vertical direction yarn z arranged in the thickness direction of the three-dimensional fabric W.

Japanese Unexamined Patent Publication No. Hei 9-164719 discloses a complex fibrous structure composed of in-plane fibers arranged in layers with respect to the component shape and a woven fabric formed in a flat shape. And a laminate obtained by integrating fibers arranged in the laminating direction. That is, as shown in FIG.
And a complicated shape portion 75 such as a bent portion or an uneven portion. In the simple shape portion 74, flat fabrics 76 and 77 are laminated, and in the complex shape portion 75, a prepreg (a material in which fibers are impregnated with resin) 78 is arranged between the flat fabrics 76 and 77. . And the whole is integrally connected by the fibers 79 in the laminating (plate thickness) direction.

[0007]

SUMMARY OF THE INVENTION However, Japanese Patent Laid-Open No.
The three-dimensional woven fabric disclosed in Japanese Patent No. 191743 is a triaxial woven fabric, and therefore has insufficient strength against a diagonal force. In addition, due to the structure of weaving with a loom, it is difficult to produce a tapered portion having a pointed tip. on the other hand,
The three-dimensional woven fabric disclosed in Japanese Patent Application Laid-Open No. 1-221559 is also a triaxial woven fabric, and therefore has insufficient strength against a diagonal force. In addition, since the end of the vertical thread z protrudes from the surface of the three-dimensional fabric, there is a problem that it is difficult to smooth the surface when a composite material is used.

In the case of the fibrous structure disclosed in Japanese Patent Application Laid-Open No. 9-164719, flat fabrics 76 and 77 are used.
And the prepreg 78 (fibers in the in-plane direction) are connected by fibers in the laminating direction, so that the manufacturing apparatus and the manufacturing method are increased in size and complexity.

The present invention has been made in view of the above-mentioned problems, and a first object of the present invention is to form at least one end in a tapered shape, to improve the adhesiveness with another composite material, and to improve the adhesiveness at the adhesive portion. It is an object of the present invention to provide a three-dimensional fiber structure suitable as a skeleton material of a composite material in which stress concentration hardly occurs, and a second object is to provide a manufacturing method thereof.

[0010]

In order to achieve the first object, according to the first aspect of the present invention, the first and second in-plane yarns arranged in a folded shape in directions orthogonal to each other are provided. A plurality of formed yarn layers, a plurality of yarn layers formed by bias yarns arranged in a folded shape in a direction intersecting with the arrangement yarns on both surfaces, and arranged in a direction orthogonal to each of the yarn layers. A three-dimensional fiber structure including a thickness direction yarn that couples each of the yarn layers, so that at least one end of the three-dimensional fiber structure is tapered and thin, and the abundance ratio of the in-plane arrangement yarn and the bias yarn is reduced. It is formed so as to have a predetermined ratio regardless of the thickness of the three-dimensional fiber structure.

According to the second aspect of the present invention, the bias yarn is approximately ± 45 with respect to the first and second in-plane arranged yarns.
They are arranged to cross at an angle of °. According to a third aspect of the present invention, in the first or second aspect, the yarn layer constituting at least one outermost layer of the tapered portion is continuous with a base end of the tapered portion. The same yarn layer constituting the outermost layer of the portion is arranged up to the tip of the tapered portion.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the yarn layer constituting the outermost layer is formed of a bias yarn. In order to achieve the second object, in the invention according to claim 5, a frame body in which regulating members can be arranged at a predetermined pitch so as to surround an area corresponding to an insertion area of the thickness direction yarn, and the frame body A jig provided with a support capable of supporting the regulating member at a predetermined pitch at a predetermined position inside the frame is regulated at a predetermined pitch at a predetermined position inside the frame corresponding to the tapered portion of the three-dimensional fiber structure. First and second in-plane arrangement yarns arranged in a folded manner in a direction orthogonal to each other, and a bias arranged in a folded state in a direction intersecting with the in-plane arrangement yarns in a state in which the member is erected and supported. After forming a laminated yarn group having a four-axis orientation by laminating a predetermined number of yarn layers arranged and arranged in a predetermined order so as to engage and fold the yarn with a predetermined regulating member, and forming the laminated yarn group, A plurality of thickness direction yarns arranged in a row while being held by the frame The input needle is pierced into the laminated yarn group together with the thickness direction yarn until the holding portion of the thickness direction yarn comes out of the laminated yarn group, and a loop of the thickness direction yarn is formed on the projecting side of the thickness direction yarn insertion needle. And a step of inserting a retaining thread through the loop along the direction of arrangement of the thickness direction thread insertion needles,
After the retaining yarn has been inserted into the loop, the process of pulling back the thickness direction thread insertion needle and tightening the layered yarn group is repeated to insert the thickness direction yarn into a predetermined insertion area, and then the layered yarn group is subjected to the above-described treatment. Removed from the tool.

Therefore, the three-dimensional fiber structure according to the first aspect of the present invention has a five-axis structure, and the existing ratio of the in-plane arrangement yarns and the bias yarns is a predetermined ratio even in the tapered portion. Therefore, the strength can be increased even in a portion having a small thickness. In addition, when a composite material is formed and used by being bonded to another composite material, stress concentration at the joint is suppressed.

According to the second aspect of the present invention, since the bias yarns are arranged so as to intersect the first and second in-plane yarns at an angle of approximately ± 45 °, they are arranged at other angles. It works most effectively against oblique forces as compared to the case where the force is applied.

According to the third aspect of the present invention, in the first or second aspect of the present invention, the outermost layer of the tapered portion is formed of the same yarn layer. When a material is formed, the surface of the tapered portion is easily formed smoothly.

In the invention according to claim 4, in the invention according to any one of claims 1 to 3, since the outermost layer is formed by a yarn layer of a bias yarn, the first and second layers are formed.
As compared with the case of forming with a yarn layer of the in-plane arrangement yarn, the density of the arrangement yarn is increased, and the surface smoothness is improved. In addition, since the minimum lamination structure is composed of two bias yarn layers in the plus direction and the minus direction, the tip can be made extremely thin, and the bonding effect can be improved.

According to the fifth aspect of the present invention, in a state where the regulating member is erected at a predetermined pitch at a predetermined position on the frame and at a predetermined position corresponding to the tapered portion of the three-dimensional fiber structure inside the frame, The first in-plane arrangement yarn, the second in-plane arrangement yarn, and the bias yarn are arranged. Each yarn is arranged in a predetermined order so as to be engaged with a predetermined regulating member and folded, thereby forming a laminated yarn group having a four-axis orientation. In a state where the laminated yarn group is held by the frame, the thickness direction yarn insertion needles arranged in one row are inserted through the laminated yarn group, and the thickness direction yarn is inserted into the laminated yarn group in a folded manner and comes out of the loop. A retaining thread is inserted. Next, the thickness direction thread insertion needle is pulled back to tighten the laminated yarn group,
The thickness direction yarn is prevented from coming off. After the thickness direction yarn is inserted into the predetermined insertion area, the laminated yarn group is removed from the jig to complete the three-dimensional fiber structure.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 2, the three-dimensional fiber structure W is formed in an outer shape in which one end side of a plate material having a constant thickness is tapered toward the front end. As shown in FIG. 1, the three-dimensional fiber structure W
Is constituted by a first in-plane arrangement yarn x, a second in-plane arrangement yarn y, bias yarns B1, B2, a thickness direction yarn z, and a retaining yarn P. The first in-plane arranged yarns x are folded at an orientation angle of 0 ° so as to extend parallel to the longitudinal direction of the three-dimensional fiber structure W, and the second in-plane arranged yarns y are folded at an orientation angle of 90 °. It is arranged in a shape. That is, the yarns x,
y are arranged in a folded shape in directions perpendicular to each other, and form thread layers parallel to each other. Note that the orientation angle means an angle formed by the yarn with the longitudinal direction of the three-dimensional fiber structure W.

The bias yarns B1 and B2 are yarns x,
They are arranged in a folded manner so as to intersect with the direction intersecting with y, that is, both the longitudinal direction and the width direction of the three-dimensional fiber structure W, and form thread layers parallel to each other. In this embodiment, the bias yarns B1 and B2 are arranged so as to intersect the yarns x and y arranged on both sides at an angle of approximately ± 45 ° (orientation angle ± 45 °). Unlike the prior art, instead of removing only the yarns arranged in a specific direction to change the thickness of the tapered portion, the in-plane arranged yarns x, y and the bias yarns B1, B2 have a three-dimensional fiber The turn-back position is set so as to have a predetermined ratio regardless of the thickness of the structure W.

In this embodiment, the three-dimensional fiber structure W is formed such that the thread layers other than the tapered portion (tapered portion) T are 22 layers. Second layer P2, fourth
Layer P4, sixth layer P6, eighth layer P8, tenth layer P10, thirteenth layer P13, fifteenth layer P15, seventeenth layer P17, first layer
The ninth layer P19 and the twenty-first layer P21 are formed of the first in-plane arrangement yarn x, and the third layer P3, the ninth layer P9, the fourteenth layer P14, and the twentieth layer P20 are formed of the second in-plane arrangement yarn y. Is formed. The first layer P1, the seventh layer P7, the sixteenth layer P16, and the twenty-second layer P22 are formed of the bias yarn B1, and the fifth layer P5, the eleventh layer P11, the twelfth layer P12, and the eighteenth layer P12 are formed.
Reference numeral 18 is formed of the bias yarn B2. That is, in this embodiment, each yarn layer is arranged almost mirror-symmetrically with respect to the neutral plane in the thickness direction of the three-dimensional fiber structure W.

In the yarn layer constituting the outermost layer on the slope side of the tapered portion T, the same yarn layer constituting the outermost layer of the portion continuous to the base end of the tapered portion T is arranged up to the leading end of the tapered portion T. . In this embodiment, the outermost layer is formed by the bias yarn layer. Further, the yarns constituting each yarn layer are formed by one continuous yarn.

The thickness direction yarns z are arranged in a direction orthogonal to the predetermined number of stacked yarn layers, and connect the yarn layers. The thickness direction yarn z is located on the surface side of the three-dimensional fiber structure W (FIG. 1).
At the upper side of the three-dimensional fiber structure W, and is prevented from coming off by the retaining yarns P arranged in the width direction on the surface side of the three-dimensional fiber structure W. Each yarn layer is joined by the thickness direction yarn z tightening each yarn layer together with the retaining yarn P.

Various fibers such as carbon fiber, glass fiber, ceramic fiber, and polyaramid fiber are used as the material of the fiber constituting each yarn, depending on the use of the composite material. In this embodiment, roving (tow) of carbon fiber is used as each yarn. Roving (tow) means a substantially non-twisted fiber bundle obtained by bundling a number of thin filaments of a single fiber. Accordingly, in FIG. 1, the shape of the cross section orthogonal to the length direction of the yarn is represented as a circle for convenience, but actually becomes a flat ellipse when the yarns are stacked as the stacked yarn group F.

Next, the configuration of a jig used for manufacturing the three-dimensional fiber structure W configured as described above will be described. This jig is used for arranging the laminated yarn groups corresponding to the shape of the three-dimensional fiber structure W, and for holding the laminated yarn groups when the thickness direction yarns z are inserted into the arranged laminated yarn groups.

As shown in FIGS. 3 and 4, the jig 1 includes a support base 2 as a support, a frame 3 placed on the support base 2, and a pressing assisting device arranged in the frame 3. And a member 4. The frame 3 is formed in a shape (rectangular in this embodiment) corresponding to the outer shape of the laminated yarn group to be manufactured, and a pin as a regulating member is formed so as to surround a region corresponding to the insertion region of the thickness direction yarn z. 5 are removably arranged at a predetermined pitch. The support base 2 has a frame 3 disposed at a predetermined position on the support base 2 and a hole for detachably standing and supporting a pipe 6 serving as a regulating member at a predetermined pitch at a predetermined position inside the frame 3. Many 2a are formed.

The pressing assisting member 4 has a plurality of supporting plates 7 arranged in parallel at predetermined intervals. When arranging the arrangement yarns x, y and the bias yarns B1, B2 in both surfaces,
As shown in FIG. 3, the jig 1 has a frame 3 disposed on a support base 2 on which a pipe 6 is erected at a predetermined position.
The pressing auxiliary member 4 is disposed inside the frame 3 for use. In this state, the pipe 6 is placed between the adjacent support plates 7 or between the support plate 7 and the inner surface of the frame 3. The pressing auxiliary member 4 plays a role of pressing the laminated yarn group when the thickness direction yarn z is inserted into the laminated yarn group arranged on the jig 1.

Next, a description will be given of a thickness direction yarn insertion device for manufacturing a three-dimensional fiber structure W by simultaneously inserting a plurality of the thickness direction yarns z into the laminated yarn group formed on the jig 1. FIG.
As shown in the figure, the thickness direction yarn insertion device 10 holds the laminated yarn group F formed on the frame body 3 so that its thickness direction is horizontal, and holds the thickness direction yarn z in the width direction of the laminated yarn group F. (Vertical direction in FIG. 10), and are inserted simultaneously one by one.

FIG. 5 is a partially cutaway schematic plan view of the thickness direction thread insertion device, and FIG. 6 is a partially cutaway schematic side view of the same. FIG.
As shown in FIG. 6, the front side (the left side in FIG. 6) is placed on the base plate (substrate) 11 of the thickness direction thread insertion device 10.
A pair of rails 12 extend in the left-right direction (perpendicular to the plane of FIG. 6), and the support table 13 extends along the rails 12.
Are slidably supported. The support table 13 is reciprocated along the rail 12 by a ball screw mechanism 15 driven by a motor 14 supported on the base plate 11. The ball screw mechanism 15 is driven via a belt transmission mechanism 16.

On the support table 13, a pair of support brackets 17 constituting a holding device are protruded. Each support bracket 17 is formed at its upper and lower rear surfaces with screw holes (both not shown) into which bolts for fixing the frame 3 are screwed at predetermined intervals. The frame 3 has a bolt insertion hole 3a (illustrated in FIGS. 2, 10 and the like) formed at a corner thereof. The support bracket 17 holds the frame 3 together with the laminated thread group F formed thereon by means of bolts penetrating through the bolt insertion holes 3a. The rotation of the ball screw mechanism 15 by the motor 14 allows the support table 13 to move along with the frame 3 at a predetermined pitch along the rail 12.

A support table 13 is provided on the base plate 11.
A pair of brackets 18 (only one is shown) are erected on the rear side, and a pair of guide rods 1 are provided between the two brackets 18.
9 is installed in parallel with the rail 12. A support plate 20 is slidably supported on the guide rod 19 via a bracket.
The air cylinder 21 fixed to 8 can reciprocate a predetermined distance.

A pair of support brackets 22 are erected at both front and rear ends of the support plate 20, and a pair of upper and lower guide rods 23 (shown in FIG. 6) are installed in parallel near the first end of the support bracket 22. I have. A ball screw 24 is rotatably supported between the guide rods 23 so as to penetrate the support brackets 22. Both guide rods 23
A movable body 25 is slidably supported on the movable body 25, and a ball nut 26 screwed to the ball screw 24 is fixed to the movable body 25. The ball screw 24 is driven to rotate forward and reverse by a drive motor 27 via a belt transmission mechanism 28.

A needle support 29 is fixed to the front end of the moving body 25, and a thickness direction thread insertion needle (hereinafter simply referred to as an insertion needle) 30 is provided at a front portion thereof at a predetermined pitch corresponding to the arrangement pitch of the pipes 6. The columns are fixed horizontally. The needle support 29 is provided so as to pass through a hole 22a (shown in FIG. 6) formed in the front support bracket 22. By the operation of the driving motor 27, the needle support 29 moves the insertion needle 30 to the standby position where the insertion needle 30 cannot be engaged with the laminated yarn group F held by the support bracket 17, and the needle hole 30a (shown in FIG.
Is moved to the position on the opposite side to the operation position that penetrates the laminated yarn group F.

Near the second end of the support bracket 22, a pair of upper and lower support rods 31 are slidably supported while penetrating the support bracket 22. Support plate 20
Near the rear support bracket 22,
The air cylinder 33 is horizontally fixed so as to extend in the front-rear direction via the air cylinder. The rear ends of the support rods 31 are connected to each other via a connection plate 34, and the connection plate 34 is connected to a piston rod 33 a of the air cylinder 33. A perforation needle support 35 is fixed to the front ends of both support rods 31, and perforation needles 36 are fixed to the perforation needle support 35 in a row at a predetermined pitch corresponding to the insertion needle 30. Piercing needle 36
Are arranged in parallel with the rows of the insertion needles 30 while maintaining a distance equal to the moving distance of the support plate 20 when the air cylinder 21 is operated. By the operation of the air cylinder 33, the puncture needle support 35 is moved to a standby position where the puncture needle 36 cannot be engaged with the laminated yarn group F held by the support bracket 17, and an operation position where the puncture needle 36 penetrates the laminated yarn group F.

As shown in FIG. 5, the air cylinder 3 is provided on the base plate 11 near the front support bracket 22.
7 is disposed horizontally so as to extend in the front-rear direction, and a pressing member 39 is fixed to a distal end of the piston rod 37a via a bracket 38. As shown in FIGS. 10 and 11, the pressing member 39 includes a support portion 39 a having an L-shaped cross section extending along the direction in which the rows of the insertion needles 30 are arranged.
Are formed with recesses 40 extending in a direction perpendicular to the direction of arrangement of the 30 rows of insertion needles in parallel at a predetermined pitch. The pressing member 39 engages with the support plate 7 of the jig 1 in the concave portion 40 and
Position. The pressing member 39 is formed to be slightly shorter than the inner width of the frame 3, and can press the laminated yarn group F via the support plate 7 without engaging with the frame 3.

The pressing member 39 is disposed on the standby position side of the insertion needle 30 and the piercing needle 36 with respect to the laminated yarn group F held by the support bracket 17, and near the insertion position of the 30 rows of insertion needles. It is arranged movably along the moving direction. The pressing member 3 is actuated by the operation of the air cylinder 37.
Reference numeral 9 denotes an operation position for pressing the stacked yarn group F held by the support bracket 17 toward the forward side of the 30 rows of the insertion needles via the support plate 7, and a standby position where the stacked yarn group F cannot be engaged.

As shown in FIGS. 5 and 6, on the base plate 11, air cylinders 41 and 42 are fixed via brackets 43 so as to extend in the front-rear direction. Piston rods 41a, 42a of air cylinders 41, 42
Press plates 44 and 45 forming a pair are fixed to the tips of the. Both press plates 44 and 45 are formed in a planar L-shape and have the same length as the pressing member 39. Each of the press plates 44 and 45 is formed such that the width of the contact portion with the laminated yarn group F is smaller than the interval between the adjacent pin 5 and pipe 6. The two press plates 44 and 45 are arranged at positions facing the insertion needle 30 or the perforation needle 36 and close to each other so as to press the laminated yarn group F together with the support plate 7 in a state orthogonal to the support plate 7. ing. By the operation of the air cylinders 41, 42, each press plate 44, 45
Is moved to an operation position where the stacked yarn group F is pressed to the retreat side of the needle row, and a standby position where the stacked yarn group F cannot be engaged.

The base plate 11 and the support table 13 are provided with holes 11a and 13a at positions corresponding to the lower ends of the stacked yarn groups F held by the support bracket 17. Then, at a position corresponding to a position at which the 30 rows of insertion needles penetrate through the laminated yarn group F, a retaining thread insertion needle (hereinafter, simply referred to as a retaining thread needle) 46 can be moved in the arrangement direction of the 30 rows of insertion needles. (The tip is shown in FIGS. 6 and 10). The retaining thread needle 46 has a vertex at the tip, is reciprocated by a drive device (not shown), and has an operation position where it passes through a loop of the thickness direction thread z connected to the thirty rows of the insertion needles 30 when arranged at the operation position. , And a standby position retracted from a position corresponding to the laminated yarn group F. The thickness direction thread insertion device 10 is basically a
The configuration is the same as that disclosed in Japanese Patent Publication No. -218249.

Next, a method for manufacturing a flat three-dimensional fiber structure W whose one end is formed in a tapered shape using the jig 1 and the thickness direction thread insertion device 10 configured as described above will be described. I do.

First, as shown in FIG. 3, a laminated yarn group F is formed using a jig 1 in which a pipe 6 is erected in a region corresponding to a tapered portion T of a three-dimensional fiber structure W. As shown in FIG. 7 (a), the bias yarn B1
And a first layer P1 as a bias yarn layer is formed so as to be folded back by engaging with the pipe 6. First layer P
Reference numeral 1 denotes a bottom surface of the three-dimensional fiber structure W. Next, as shown in FIG. 7B, the first in-plane arrangement yarn x is 0 °.
The second layer P2 is arranged so as to engage with the pin 5 and the pipe 6 at an orientation angle of and turn back, and as a first in-plane yarn layer.
Is formed. The first in-plane arrangement yarn x forming the second layer P2 is folded back before the bias yarn B1 forming the first layer P1.

Next, as shown in FIG. 7 (c), the second in-plane arrangement yarns y are arranged so as to be engaged with the pins 5 at an orientation angle of 90 ° and to be folded back, and the second in-plane arrangement yarns are arranged. A third layer P3 as a thread layer is formed. Next, as shown in FIG.
Are arranged so as to engage with the pin 5 and the pipe 6 at an orientation angle of 0 ° to be folded, thereby forming a fourth layer P4 as a first in-plane arranged yarn layer. The first of the fourth layer P4
The in-plane arrangement yarn x is a bias yarn B1 when the first layer P1 is arranged.
Are engaged with the pipe 6 disposed closer to the end of the tapered portion T by one pitch (rightward in FIG. 7) than the pipe 6 to be folded. Next, as shown in FIG. 7 (e), the bias yarn B2 is arranged so as to engage with the pin 5 and the pipe 6 at an orientation angle of -45 [deg.] To be folded, and a fifth layer P5 as a bias yarn layer is formed. It is formed. The bias yarn B2 of the fifth layer P5 is folded back by engaging with the pipe 6 disposed one pitch closer to the end side of the tapered portion T than the pipe 6 where the first in-plane arranged yarn x of the fourth layer P4 is folded. It is.

Hereinafter, similarly, as shown in FIG.
The in-plane arrangement yarn x, the bias yarn B1, the first in-plane arrangement yarn x, the second in-plane arrangement yarn y, the first in-plane arrangement yarn x, and the bias yarn B2 are arranged in this order. A sixth layer P6 to an eleventh layer P11 are formed. The in-plane arrangement yarns x and y and the bias yarns B1 and B2 are arranged so as to be engaged with the pins 5 or the pipes 6 at positions corresponding to the designed predetermined positions so as to be folded back.

Thereafter, similarly, the twelfth layer P12 to the second
The laminated yarn group F is formed by forming up to the two layers P22.
The in-plane arranged yarns x and y and the bias yarns B1 and B2 constituting the respective yarn layers of the twelfth layer P12 to the twenty-second layer P22 are separated from the first layer P.
1st to 11th layers P11, 12th layer P12 to 22nd layer P2
2 are arranged in a sequence other than the tapered portion T so as to be almost mirror-symmetric with respect to the neutral plane in the thickness direction of the three-dimensional fiber structure.

In order to increase the density and adjust the thickness of the laminated yarn group F, each time the arrangement of the yarn layers is completed, or each time an appropriate yarn layer is formed, the yarn layers are pressed from above by a pressing member. When pressed, the laminated yarn group F is compressed.

After arranging all the yarn layers, the support base 2 is removed, and the pipe 6 is inserted through the laminated yarn group F.
5 in a state where the pressing auxiliary member 4 is mounted on the frame 3.
As shown in (1), the frame 3 is fixed to the support bracket 17 of the support table 13 by bolts together with the laminated yarn group F. The support table 13 is disposed at a position where the pipe 6 corresponding to the end of the layer group F on the taper portion T side starts insertion of the thickness direction thread z corresponding to the perforation needle 36. The position of the support table 13 shown in FIG. 5 is a position at the time when the insertion of the thickness direction thread z almost approaches the end. The support table 13 is arranged at the insertion start position, and the insertion needle 3
0, piercing needle 36, pressing member 39 and press plate 4
The operation of inserting the thickness direction yarn z into the laminated yarn group F is started from the state where the 4, 45 are arranged at the standby position.

First, the air cylinder 37 is operated, and FIG.
As shown in (2), the pressing member 39 is disposed at an operating position where the pressing member 39 engages with the support plate 7. Next, the air cylinders 41 and 42 are actuated to place the two press plates 44 and 45 in the operation position, and the pressing member 39 and the two press plates 44 and 45 compress the laminated yarn group F at a position corresponding to the 36 rows of perforating needles. Is held. In this state, the air cylinder 33 is actuated, and the perforating needle 36 advances to a position where it penetrates the laminated yarn group F, and then retracts to the original position. The perforating needle 36 engages with the pipe 6 at the time of its advance, and then penetrates the laminated yarn group F while pushing the pipe 6 out of the laminated yarn group F. The piercing needle 36 moves along the trace of the pipe 6 while being guided by the support plate 7 and the two press plates 44 and 45. Even if the piercing needle 36 is slightly bent, the piercing needle 36 is perpendicular to the laminated yarn group F. It is inserted. Since the laminated yarn group F is pressed by the support plate 7 and the press plates 44 and 45, the arrangement of the yarns is not disturbed when the perforating needle 36 advances. The fibers constituting the laminated yarn group F are the support plate 7 and the two press plates 44, 4
5, the holes are formed in the trace of the perforation needle 36 because they are arranged to some extent densely by the compressing action of No. 5.

Next, the air cylinder 21 is protruded to move the 36 rows of the puncturing needles and the 30 rows of the inserting needles 30 together with the support plate 20, and the 30 rows of the inserting needles 30 are arranged at positions facing the holes where the piercing needles 36 are removed. You. In that state, the air cylinder 4
After the actuation 1 is operated to place the press plate 44 at the standby position, the drive motor 27 is operated, and the insertion needle 30 moves forward and is arranged at the operation position. The insertion needle 30 is inserted through the laminated yarn group F until the needle hole 30a comes forward of the laminated yarn group F.
After the insertion needle 30 reaches the forward end, the drive motor 27 is rotated in the reverse direction, and the insertion needle 30 is slightly retracted. As a result, a state is formed in which the thickness direction thread z connected to the needle hole 30a from the laminated thread group F forms a loop that allows the retaining thread needle 46 to pass.

Next, the retaining thread needle 46 is operated, and the retaining thread P is inserted through the loop. Thereafter, the drive motor 27 is rotated in the reverse direction, and the insertion needle 30 is retracted, separated from the laminated yarn group F, and placed at the standby position. Air cylinder 4
1 is actuated and the press plate 44 is again placed in the working position. In this state, the thickness direction yarn z is pulled back by the operation of the tension adjusting unit (not shown), and the thickness direction yarn z inserted into the laminated yarn group F is tightened in a state where the thickness direction yarn z is prevented from coming off by the retaining yarn P. . Next, the air cylinder 21 is operated, and the 36 rows of the puncture needles and the 30 rows of the insertion needles are returned to the initial positions together with the support plate 20. Air cylinder 3
7, 41 and 42 are operated, and the pressing member 39 and the press plates 44 and 45 are arranged at the standby position. Thus, one insertion cycle of the thickness direction thread z is completed.

Next, the motor 14 is driven to move the support table 13 by the insertion pitch of the thickness direction thread z.
6 is in a state of facing the next thickness direction yarn insertion position in the laminated yarn group F. Thereafter, the insertion cycle of the thickness direction yarn z is sequentially executed in the same manner as described above. When the thickness direction yarn z is inserted into a portion other than the tapered portion T of the laminated yarn group F, the pipe 6 does not exist at the position, but the laminated yarn group F is somewhat compressed by the compressing action of the support plate 7 and the press plates 44 and 45. It is perforated by the perforation needle 36 in a densely arranged state. Accordingly, a hole is formed in the trace of the perforation needle 36, and the insertion needle 30 penetrates the laminated yarn group F at the hole. And
Each yarn layer constituting the laminated yarn group F is connected by the thickness direction yarn z. After the insertion of the thickness direction yarn z into the entire thickness direction yarn insertion area of the laminated yarn group F is completed, each pin 5 is removed from the frame 3, and the three-dimensional fiber structure W is removed from the frame 3, The manufacture of the three-dimensional fiber structure W is completed.

When the pressing member 39 is disposed in the operating position in the vicinity of the second end of the frame 3, the pressing member 39 interferes with the frame 3, so that the pressing of the pressing member 39 is not performed, and the thickness direction yarn z is not pressed. Insertion takes place. However, at this point, the insertion of the thickness direction yarn z into most of the thickness direction yarn insertion area of the laminated yarn group F has been completed. Accordingly, most of the laminated yarn group F is in a state of being tightened by the thickness direction yarn z, and since the frame body 3 is located near the place where the thickness direction yarn z is to be inserted, the press plate 45 and the frame The body 3 holds the laminated yarn group F in a compressed state. As a result, the insertion and tightening of the thickness direction thread z can be performed smoothly even if the pressing operation of the support thread 7 with the support plate 7 via the pressing member 39 is not performed.

For convenience of illustration, the schematic perspective views shown in FIGS. 3 and 4 and the schematic sectional views shown in FIGS. 7 to 9 and the schematic perspective views shown in FIG. Etc. are different.

The three-dimensional fiber structure W configured as described above is used as a reinforcing material (frame material) of a fiber-reinforced composite material, and a resin or an inorganic material is used as a matrix. For example, when forming a carbon / carbon composite material, the three-dimensional fiber structure W is impregnated with a resin, cured, and then fired. Then, the fiber reinforced composite material is used by being bonded to another composite material with an adhesive.

For example, when a composite material having a three-dimensional fiber structure as a reinforcing material is used as a hinge member of a door of a front leg storage part of an aircraft, as shown in FIG.
a and a three-dimensional fiber structure having a block portion 47b. Then, a composite material 47 is manufactured using the three-dimensional fiber structure as a skeleton material, and bonded to a predetermined position of a plate-shaped composite material 48 formed from prepreg using an adhesive. A metal or ceramic bearing member 49 is attached to a portion where the hinge shaft (not shown) is inserted. The hole for mounting the bearing member 49 is formed at the stage of the three-dimensional fiber structure or after the composite material 47 is manufactured.

In the adhesive joint method in which the composite materials are adhered to each other with an adhesive, the angle of the tapered portion and the thickness of the tip portion affect the strength of the joint. The thickness of the tip portion affects the stress concentration, and the thicker the tip portion, the higher the stress concentration. The angle of the tapered part is 10
° or less, the strength of the joint is increased.

This embodiment has the following effects. (A) The three-dimensional fiber structure W has a five-axis structure, and the existing ratio of the in-plane arranged yarns x and y and the bias yarns B1 and B2 has a predetermined ratio even in the tapered portion T. Therefore, a composite material using the three-dimensional fiber structure W as a reinforcing material is:
The strength is stable and excellent even in portions having different thicknesses, stress concentration is less likely to occur at the bonding portion with another composite material, and the bonding strength, that is, the load (load) that the bonding portion can endure increases.

(B) The bias yarns B1, B2 constituting the three-dimensional fiber structure W are formed by the first and second in-plane arranged yarns x, B.
They are arranged to intersect with y at an angle of approximately ± 45 °. Therefore, it functions most effectively with respect to a force in an oblique direction, as compared with a case where the arrangement is performed at another angle.

(C) Since the yarn layer constituting the outermost layer of the tapered portion T is formed of the same yarn layer, the surface of the tapered portion T can be easily formed smoothly when a composite material is formed. Therefore, there is no need for post-processing to smooth the surface,
Or less.

(D) To change the thickness of the tapered portion T, the yarn forming each yarn layer is not cut at a predetermined position, but is engaged with the thickness direction yarn z at a predetermined position. Since the yarns are arranged so as to be folded back, the folded position of each yarn is set at a predetermined position, the straightness of the yarn is improved, and the physical properties of the composite material are improved.

(E) Since the outermost layer is formed of the yarn layer of the bias yarn, the outermost layer is formed of a yarn layer of the first in-plane arrangement yarn x or the second in-plane arrangement yarn y. The density of the yarns arranged on the outermost layer is increased, and the smoothness of the surface is improved. In addition, since the minimum lamination structure is composed of two bias yarn layers in the plus direction and the minus direction, the tip can be made extremely thin, and the bonding effect can be improved.

(F) Since each yarn layer is arranged almost mirror-symmetrically with respect to the neutral plane in the thickness direction of the three-dimensional fiber structure W, warpage is less likely to occur when the composite material is formed. (G) Since at least one continuous yarn in the yarn layer is used as a yarn constituting each yarn layer, it is easy to arrange the yarns with an appropriate tension applied,
It contributes to the improvement of the physical properties of the composite material.

(H) Since the pipe 6 is used as a regulating member arranged in the insertion area of the thickness direction thread z, the perforating needle 36 is used when the thickness direction thread z is inserted into the laminated yarn group F.
Is engaged with the hole of the pipe 6 to form the pipe 6 into the laminated yarn group F.
Easier to push out.

(I) The thickness direction thread z is inserted in a folded shape at a position where the pipe 6 supported upright on the inside of the frame 3 is pushed out of the laminated thread group F. Then, the yarns forming the intermediate layer of the laminated yarn group F and arranged to be folded in the middle of the tapered portion T are positioned at predetermined positions until the respective yarn layers are joined by the thickness direction yarn z, and the folded portion is formed. Is securely engaged with the thickness direction thread z and positioned. Therefore, the three-dimensional fiber structure W in which the straightness of the yarn is improved and the physical properties of the composite material are improved is obtained.

(G) When the thickness direction thread z is inserted, the frame 3
Is held by the support plate 7 which receives a pressing force while being positioned by the pressing member 39, and the press plates 44 and 45. Therefore, even when the pipe 6 is inserted into the laminated yarn group F, it is easy to press a necessary portion of the laminated yarn group F. In addition, the support plate 7 also functions as a guide, which facilitates formation of holes at predetermined positions of the laminated yarn group F by the perforation needles 36.

The embodiment is not limited to the above, and may be embodied as follows, for example. The three-dimensional fiber structure W may have a structure in which yarns are arranged in a total of five axes in three directions of X, Y, and Z orthogonal to each other and in two directions intersecting both directions of X and Y. The orientation angles of the yarns B1 and B2 may be other than ± 45 °.

The yarn layers constituting the three-dimensional fiber structure W may be arranged in a manner other than substantially mirror-symmetric with respect to the neutral plane in the thickness direction of the three-dimensional fiber structure W. For example, the orientation angles of the bias yarns constituting the twelfth layer P12, the sixteenth layer P16, the eighteenth layer P18, and the twenty-second layer P22 are 45 ° and −4.
The order may be 5 °, 45 °, and −45 °. In addition, a pair of bias yarns B1 and B2 having different orientation angles may be arranged so as to be adjacent yarn layers.

Instead of forming the outermost layer of the three-dimensional fiber structure W with the bias yarn B1 having an orientation angle of 45 °, the orientation angle −
45 ° bias yarn B2 or bias yarn B1
, B2 instead of the first in-plane arrangement yarn x or the second in-plane arrangement yarn y. The arrangement of the thickness direction yarns z is not limited to the arrangement in which the yarn layers are fastened together with the retaining yarns P.
As in the fiber structure disclosed in Japanese Patent No. 84906, a structure may be adopted in which the thickness direction yarns z themselves pass through each yarn layer by a chain stitch method so as to perform a function of preventing the yarns from coming off. Further, an arrangement method in which a step of inserting the thickness direction yarn z from the front side to the back side of the laminated yarn group F and a step of inserting the thickness direction yarn z from the back side to the front side may be alternately repeated.

The yarn layer forming the outermost layer of the tapered portion T of the three-dimensional fiber structure W is formed by the yarn forming the same yarn layer forming the outermost layer of the portion continuous to the base end of the tapered portion T. Instead, the configuration may be such that the folded portions of the yarns forming different yarn layers are exposed on the slope of the tapered portion T.

The shape of the three-dimensional fiber structure W is not limited to the shape in which the slope portion is formed on one side as the tapered portion T as shown in FIG. 2, and may be appropriately changed according to the shape of the target final product. Is also good. For example, as shown in FIG. 14, a tapered portion T having a slope portion formed on one side (one end) may be formed on one side (one end), or a tapered portion T having a slope portion formed on one side as shown in FIG. May be provided.
Further, the shape of the three-dimensional fiber structure W is not limited to the shape in which the portion continuous to the base end of the tapered portion T extends with the same thickness as the base end of the tapered portion T, and the thickness is larger than the base end of the tapered portion T. The shape may be increased.

The diameter of the perforating needle 36 is formed to be the same as the diameter of the regulating member erected on the support base 2, and the spacing between the support plates 7 is made the same as the diameter of the regulating member. In this configuration, the regulating member is sandwiched between the adjacent support plates 7 or between the frame 3 and the support plate 7. Therefore, even when the frame 3 is detached from the support base 2 together with the regulating member inserted into the laminated yarn group F, the regulating member inserted through the laminated yarn group F is arranged at the pitch of the holes 2 a of the support base 2. Is held at a predetermined position. As a result, the puncture needle 3 is used as a regulating member.
Even when a normal pin is used without using a pipe 6 having a shape whose end opposite to the pipe 6 is easily engaged with the piercing needle 36 or a special pin having a concave portion, the piercing by the piercing needle 36 is also possible. Becomes easier. Therefore, a low-cost ordinary pin can be used, and the manufacturing cost is reduced.

Depending on the thickness of the laminated yarn group F and the type of fiber, the regulating member (pipe 6) is pushed out of the laminated yarn group F by the insertion needle 30 without punching the hole with the piercing needle 36, and in the portion without the regulating member, Needle 3 inserted directly into laminated yarn group F
0 may be inserted to insert the thickness direction thread z. In this case, the configuration of the thickness direction thread insertion device 10 is simplified because the perforating needle 36 and its driving device are not required.

The number of the press plates 44 and 45 arranged on the projecting side of the insertion needle 30 with respect to the laminated yarn group F is not limited to two, and may be one. In the case where the number is one, when the insertion needle 30 is inserted through the laminated yarn group F in a state where the press plate is arranged at the operation position, the formation of the loop of the thickness direction thread z on the protruding side of the insertion needle 30 is hindered. Place it on the other side.

Omitting the recess 40 of the pressing member 39,
The support plate 7 may be simply pressed without the positioning of the support plate 7 by the pressing member 39. In this case, the manufacturing of the pressing member 39 is simplified.

The technical ideas (inventions) other than those described in the claims, which can be understood from the above embodiments, will be described below together with their effects. (1) In the invention according to any one of claims 1 to 4, at least the threads forming each thread layer of the tapered portion are arranged so as to be folded back in a state of engaging with the thickness direction thread. ing. In this case, the folding position of each yarn is positioned at a predetermined position, and the straightness of the yarn is improved,
The physical properties of the composite material are improved.

(2) In the third or fourth aspect of the present invention, each of the yarn layers is arranged almost mirror-symmetrically with respect to a neutral plane in a thickness direction of the three-dimensional fiber structure. In this case, warpage hardly occurs when the composite material is formed.

(3) In the invention according to claim 5,
The thickness direction yarn is inserted in a folded shape at a position where the regulating member supported upright and supported inside the frame body is pushed out of the laminated yarn group. In this case, the folded portion of the yarn arranged so as to be folded in the middle of the tapered portion while forming the intermediate layer of the laminated yarn group is reliably engaged with the thickness direction yarn and positioned, and the straightness of the yarn is improved, The physical properties of the composite material are improved.

[0075]

As described in detail above, claims 1 to 4 are provided.
According to the invention described in (1), it is possible to obtain a composite material in which the adhesiveness with another composite material is improved and stress concentration at the bonded portion is less likely to occur.

According to the second aspect of the present invention, the bias yarn constituting the three-dimensional fiber structure functions most effectively against a diagonal force. According to the third aspect of the present invention, when the composite material is formed, the surface of the tapered portion can be easily formed smoothly, and post-processing for smoothing the surface is unnecessary or reduced.

According to the invention described in claim 4, the outermost layer is arranged on the outermost layer as compared with the case where the outermost layer is formed by the yarn layer of the first in-plane arranged yarn or the second in-plane arranged yarn. The density of the yarn is increased, and the smoothness of the surface is improved. In addition, since the minimum lamination structure is composed of two bias yarn layers in the plus direction and the minus direction, the tip can be made extremely thin, and the bonding effect can be improved.

According to the fifth aspect of the present invention, a three-dimensional fiber structure suitable for a skeleton material of a composite material in which adhesion to other composite materials is improved and stress concentration is less likely to occur at a bonding portion is improved. Can be manufactured well.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a three-dimensional fiber structure according to an embodiment.

FIG. 2 is a schematic perspective view of the same.

FIG. 3 is a schematic perspective view of a jig used for forming a laminated yarn group.

FIG. 4 is an exploded perspective view thereof.

FIG. 5 is a schematic plan view of a thickness direction yarn insertion device.

FIG. 6 is a schematic side view of the same.

FIGS. 7A to 7E are schematic diagrams showing the arrangement of yarns in first to fifth layers.

FIGS. 8A to 8D are schematic views showing the arrangement of yarns in the tenth to thirteenth layers.

FIGS. 9A to 9D are schematic views showing the arrangement of yarns in the 19th to 22nd layers.

FIG. 10 is a schematic perspective view illustrating the operation of the thickness direction thread insertion device.

FIG. 11 is a schematic perspective view of a pressing member.

FIG. 12 is a schematic cross-sectional view illustrating the operation of a pressing member.

FIG. 13 is a schematic perspective view showing an example of a use state of the three-dimensional fiber structure.

FIG. 14 is a schematic perspective view of another three-dimensional fiber structure.

FIG. 15 is a schematic perspective view of another three-dimensional fiber structure.

FIG. 16 is a schematic side view showing a joined state of two composite materials.

FIG. 17 is a schematic sectional view showing a woven state of a conventional three-dimensional woven fabric.

FIG. 18 is a schematic sectional view of another conventional three-dimensional fabric.

FIG. 19 is a schematic perspective view of another conventional fiber structure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Jig, 2 ... Support base as a support, 3 ... Frame,
5 ... pin as a regulating member, 6 ... pipe as a regulating member, 30 ... thickness direction thread insertion needle, x ... first in-plane arrangement thread,
y: second in-plane arrangement yarn, z: thickness direction yarn, B1, B2 ...
Bias yarn, F: laminated yarn group, P: retaining yarn, W: three-dimensional fiber structure.

Continued on the front page (72) Inventor Fujio Hori 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (72) Inventor Tohru Ito 1 Kawasaki-cho, Kakamigahara-shi, Gifu Prefecture Kawasaki Heavy Industries Gifu Plant Co., Ltd. (72) Inventor Kaoru Onohara 1 Kawasaki-cho, Kakamigahara City, Gifu Prefecture Kawasaki Heavy Industries, Ltd.

Claims (5)

[Claims] 1. A plurality of yarn layers formed by first and second in-plane arranged yarns arranged in a folded shape in directions orthogonal to each other, and a folded shape in a direction intersecting with the in-plane arranged yarns. A three-dimensional fiber structure including a plurality of yarn layers formed by bias yarns arranged in a direction, and a thickness direction yarn that is arranged in a direction orthogonal to each of the yarn layers and connects the respective yarn layers. , So that at least one end side is tapered,
Further, the three-dimensional fiber structure is formed such that the abundance ratio of each of the in-plane arrangement yarns and the bias yarns becomes a predetermined ratio regardless of the thickness of the three-dimensional fiber structure. 2. The three-dimensional fiber structure according to claim 1, wherein the bias yarns are arranged so as to intersect the first and second in-plane yarns at an angle of approximately ± 45 °. 3. The yarn layer forming at least one outermost layer of the tapered portion is the same yarn layer forming the outermost layer of the portion continuous to the base end of the tapered portion. The three-dimensional fiber structure according to claim 1 or 2, wherein the three-dimensional fiber structure is arranged up to a tip. 4. The three-dimensional fiber structure according to claim 1, wherein the yarn layer constituting the outermost layer is formed of a bias yarn. 5. A frame body in which regulating members can be arranged at a predetermined pitch so as to surround an area corresponding to an insertion area of the thickness direction yarn,
Using a jig provided with a support capable of supporting the regulating member at a predetermined pitch at a predetermined position inside the frame, and using a jig at a predetermined position inside the frame corresponding to the tapered portion of the three-dimensional fiber structure. First and second in-plane arrangement yarns arranged in a folded manner in directions orthogonal to each other while the regulating member is erected and supported at a pitch, and arranged in a folded shape in a direction intersecting with the in-plane arrangement yarns. After forming a laminated yarn group having a four-axis orientation by laminating a predetermined number of yarn layers formed by arranging a bias yarn to be engaged with a predetermined regulating member and folding in a predetermined order to form a laminated yarn group having a four-axis orientation, In a state where the yarn group is held in the frame, a plurality of thickness direction yarn insertion needles arranged in one row are simultaneously arranged with the thickness direction yarn in the stacked yarn group and the thickness direction yarn holding portion is located outside the stacked yarn group. Until it comes out, and insert the thickness direction thread Forming a, a step of inserting in the arrangement direction of the thickness direction thread insertion needle lock yarn exits the loop, after the lock yarn exits the loop is inserted,
Repeating the step of pulling back the thickness direction yarn insertion needle and tightening the laminated yarn group, and inserting the thickness direction yarn into a predetermined insertion area,
Then, a method of manufacturing a three-dimensional fiber structure in which the laminated yarn group is detached from the jig.