JPH0559634A - Three-dimensional woven fabric - Google Patents

Abstract

PURPOSE:To obtain a three-dimensional woven fabric capable of enhancing strength in connected parts readily causing stress concentration and improving fastness (durability) for tensile and compressive loads in its use as a skeletal material in composite materials of a shape in which plural platy parts are joined such as beam materials of modified cross section in the shape of L, U, etc. CONSTITUTION:Plural platy parts (1a) and (1b) are formed into a continuous shape through a curved part 2. In the respective platy parts (1a) and (1b), yarn layers composed of yarn, laminated into many layers in the platy parts and oriented in at least two direction are connected with yarn (z) in the thickness direction inserted in a folded back form in the thickness direction of the yarn layers. The curved part 2 is constructed of yarn layers composed of in-plane oriented yarns oriented in a continuous state straddling the adjacent platy parts (1a) and (1b) and rods (zr) as yarn in a component in the thickness direction oriented in the unfolded back state in the thickness direction of the curved part 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional woven fabric, and more particularly to a three-dimensional woven fabric suitable as a skeleton material of a composite material having a plurality of faces.

[0002]

2. Description of the Related Art Orthogonal triaxial three-dimensional fabric composed of three component yarns in the X, Y and Z directions, or a triaxial fabric having five component axes including component yarns obliquely arranged in the longitudinal direction A composite material in which a three-dimensional woven fabric is a skeletal material and a resin or an inorganic material is a matrix is expected to be widely used as a structural material for rockets, aircrafts, automobiles, ships and buildings. Then, in order to make the three-dimensional fabric usable as a skeleton material of the composite material in a wide range of applications, a cross-sectional shape other than a rectangular shape, for example, an L-shaped, U-shaped, or other irregular-shaped cross section, that is, plural A three-dimensional woven fabric in which the plate-shaped portion is formed in a continuous shape via the curved portion is required.

Conventionally, as a three-dimensional woven fabric of this type with a modified cross section, Japanese Patent Laid-Open No. 1-292162 has at least two plates integrally joined in a crossed state by fiber yarns, and at least one plate. The plates other than the plates are composed of three axial fiber yarns in the longitudinal direction, the transverse direction, and the vertical direction, and the at least one plate has longitudinal, transverse, and vertical yarns, and the longitudinal direction. Also, there has been proposed a 5-axis orientation type structure in which the fiber yarns in two directions that are diagonally skewed with respect to the arrangement direction of the fiber yarns in the lateral direction and intersect each other are provided. For example, as shown in FIG. 7, a three-dimensional fabric having an H-shaped cross section has a first plate 31 serving as a reference and four second plates 32 integrally formed in a state orthogonal to the first plate 31.
And each plate 31, 32 is connected by a yarn arranged in the thickness direction of the first plate 31.

When manufacturing this three-dimensional woven fabric, the first yarn guide tube G1 and the second yarn guide tube G2 are erected in a predetermined arrangement pattern, and first, the first yarn guide tube A layer in which the yarns are arranged in the X-axis and Y-axis directions is laminated and formed in a portion located below the first plate 31 in the arrangement area of the guide tube G1. Next, the yarns constituting the first plate 31 are placed on the X-axis and Y-axis in the area where the two yarn guide tubes G1 and G2 are arranged.
Layers that are arranged obliquely with respect to the axis and both directions are laminated, and then the X axis and the Y axis are provided in a portion located above the first plate 31 in the arrangement area of the first yarn guide tube G1. Layers in which yarns are arranged in the axial direction are laminated. Then, by inserting the yarn in a loop shape from one end of each of the yarn guide tubes G1 and G2 and replacing it with the yarn guide tubes G1 and G2, and inserting a thread into the tip loop to prevent the thread from coming off. The laminated portions are connected by the yarns extending in the Z direction to finally manufacture the three-dimensional woven fabric.

Further, a sheet member 33 such as a flat cloth impregnated with resin as a composite material having a curved portion or a UD material (intermediate base material in which fibers are arranged in a sheet in one direction and resin is attached) is used. It has also been proposed that after stacking in multiple layers to form a desired shape as shown in FIG. 8, each layer is sewn with a thread 34 by a sewing machine (so-called stitching) in order to prevent delamination of each layer.

[0006]

However, the three-dimensional fabric disclosed in the above-mentioned Japanese Patent Laid-Open No. 1-292162 is a yarn which is arranged so as to be continuous with two surfaces across a joint portion of two surfaces which are orthogonal to each other. Does not exist. For example, in the three-dimensional woven fabric having the shape shown in FIG. 7, there are no yarns arranged continuously in the XY plane and the YZ plane. X of the first plate 31
When the force in the direction of the arrow in FIG. 7 acts on the second plate 32, the yarns forming the Y surface have almost no action against the bending stress acting on the second plate 32, and There is almost no action against the force acting to separate the plate 32 from the joint with the first plate 31. Therefore, there is a problem that the strength of the composite material becomes insufficient.

On the other hand, in the case of stitching, flat sheets made of flat cloth or UD material laminated in multiple layers can be sewn, but the curved portion cannot be sewn, which causes peeling. Further, in stitching, there is also a problem that the flat cloth and the fibers of the UD material to be sewn are damaged by the needle.

The present invention has been made in view of the above problems, and an object thereof is to join a plurality of plate-like portions such as a girder member having an L-shaped, U-shaped or other irregular cross section. To provide a three-dimensional woven fabric capable of improving the strength (durability) against a tensile load and a compressive load by increasing the strength of a connection portion where stress concentration easily occurs when used as a skeleton material of a shaped composite material. is there.

[0009]

In order to achieve the above object, the three-dimensional woven fabric of the present invention is formed such that a plurality of plate-shaped portions are continuous through a curved portion, and each plate-shaped portion has a thickness. The yarns constituting the directional component are inserted in a folded shape so as to join the yarn layers made up of the yarns laminated in multiple layers on the plate-shaped portion and arranged in at least two directions, and the curved portion extends over the adjacent plate-shaped portion. It is composed of a yarn layer composed of in-plane arranged yarns arranged in a continuous manner and yarns of a thickness direction component arranged non-folded in the thickness direction of the curved portion.

[0010]

In the in-plane arranged yarns forming the curved portion connecting the adjacent plate-shaped portions, the yarns arranged in a state intersecting the width direction of the curved portion are tensioned by the tension of the yarns and are placed at the center of curvature of the curved portion. Receive a centripetal force toward you. Therefore, unlike the plate-like portion, such an in-plane arrayed yarn layer tends to maintain a stable shape even when there is no yarn for connecting the upper and lower layers in a laminated state. When a composite material that is a skeletal material is formed, the yarn in the thickness direction component that is arranged in a non-folded manner in the thickness direction of the curved portion further enhances the coupling of the in-plane arranged yarn layer and the tensile load in the thickness direction. Shows great resistance to. Also, when a load is applied to a certain plate-shaped portion, the presence of the thread arranged across the plate-shaped portion and the other plate-shaped portion acts on the curved portion that is the joint portion of both plate-shaped portions. The yarn effectively contributes to the stress generated and the strength is improved.

[0011]

【Example】

(Embodiment 1) A first embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 2, the three-dimensional woven fabric F has a substantially L-shaped cross section in which two plate-shaped portions 1a and 1b which are orthogonal to each other are connected by a curved portion 2. Plate part 1
a and 1b are x-yarn layers composed of in-plane arrayed yarns x arranged parallel to the width direction of the curved portion 2, and in-plane arrayed yarns arranged in a direction parallel to the x-yarn layer in a plane parallel to the x-yarn layer. The y yarn layer composed of y and the in-plane arranged yarn arranged so as to be inclined at a predetermined angle (45 ° in this embodiment) with respect to the in-plane arranged yarns x and y in a plane parallel to the x yarn layer. And a thickness direction thread z which is arranged in the thickness direction of the woven fabric in a state orthogonal to each of the thread layers to connect the layers to each other.

As shown in FIG. 1, the x yarn layer, the y yarn layer and the bias yarn layer of the plate-like portions 1a and 1b are integrally formed by arranging one yarn in each layer in a folded shape. Has been done. The in-plane arranged yarn y and the bias yarn B are arranged so as to be continuous across the plate-shaped portions 1a and 1b in a state of intersecting the width direction of the curved portion 2. The curved portion 2 includes a portion of each of the in-plane arranged yarns x and y and the bias yarn B arranged so as to be continuous over both plate-shaped portions 1a and 1b, and the curved portion between the yarns. It is composed of a large number of rods zr as yarns of the thickness direction component which are arranged in a non-folded manner in the thickness direction. The rod zr is formed by fixing a fiber bundle with resin. In the outermost layer of the bending portion 2, a yarn layer that is arranged in a state intersecting with the width direction of the bending portion 2, that is, a yarn layer including the in-plane arranged yarn y or the bias yarn B is arranged.

As described above, the three-dimensional woven fabric F is a five-dimensional woven fabric in which in-plane four-axis oriented woven fabrics are bound by the thickness direction threads z or rods zr on all surfaces. When a load in the direction of the arrow in FIG. 2 acts on the composite material formed by impregnating the three-dimensional fabric F configured as described above with a resin, a large stress acts on the curved portion 2 of the three-dimensional fabric F. The in-plane array yarn y and the bias yarn B are both plate-shaped portions 1a,
Since the yarns (fibers) extend in a direction intersecting the width direction of the curved portion 2 which is the connecting portion of the 1b and are arranged so as to straddle both plate-shaped portions 1a and 1b, those threads (fibers) act on the curved portion 2. The strength of the composite material is improved by effectively contributing so as to share the force in the direction of withstanding the applied stress.

The yarn layers extending in the direction intersecting the widthwise direction of the curved portion 2 and arranged across the plate-like portions 1a and 1b press the curved surface toward the center of curvature by the tension of each yarn. Therefore, unlike the plate-shaped portions 1a and 1b, it is not necessary to press each yarn layer in the thickness direction by the thickness direction yarn z arranged in a folded shape to combine them. The rods zr arranged in the thickness direction of each yarn layer on the curved portion 2 restrict the positions of the in-plane arranged yarns x and y and the bias yarn B which are arranged in a plurality of layers along the curved surface, and between the layers. Play a role and. In particular, it exhibits a large resistance to an outward tensile load applied to the curved portion 2 and a stronger durability than an ordinary laminated material against an inward compressive load. In addition, since the three-dimensional woven fabric of this example has five-axis orientation on all surfaces, the amount of deformation with respect to a diagonal force is greater than that of a composite material using a three-dimensional woven fabric of orthogonal three-axis arrangement as a skeleton material. Is reduced, and high strength is exhibited not only against tensile load and compression load but also against torsion load.

Next, an example of a method of manufacturing the above-mentioned three-dimensional fabric F will be described. When manufacturing the three-dimensional woven fabric F, as shown in FIG. 3, an L-shape corresponding to the outer diameter of the three-dimensional woven fabric is formed, and a large number of pipes 3 for regulating the arrangement of the yarns are perpendicular to the surface at predetermined positions. The substrate 4 installed upright is used. Figure 4
As shown in FIG. 3, each pipe 3 is detachably attached to the hole 4a formed in the substrate 4. A pair of notched grooves 3a having a width that allows the thickness direction thread z to pass through is formed at the base end of the pipe 3 erected on the flat surface portion of the substrate 4.

Before mounting the pipe 3 on the substrate 4, each hole 4a
The u-shaped pin 5 is inserted into the U-shaped pin 5, and the pressure bar 6 is arranged between the u-shaped pins 5. Next, the thickness direction threads z are arranged in a state of being passed through the u-shaped pin 5. Thickness direction thread z is u-shaped pin 5
One is arranged for each column. Next, the u-shaped pin 5 is inserted into the pipe 3, and the pipe 3 is inserted into each hole 4a while the thickness direction thread z is inserted into the cutout groove 3a. As a result, as shown in FIG.
Are arranged in a meandering state, and the required length of the thickness direction thread z is secured by selecting the thickness of the pressure bar 6.
In this state, the in-plane array yarns x, y are arranged between the pipes 3 on the substrate 4.
And a pipe 3 in which the bias yarn B is arranged at the end of the substrate 4.
Are arranged so as to be folded back in a state of engaging with the x thread layer, y
A yarn layer and a bias yarn layer are sequentially laminated. The in-plane array yarn x is folded back in a state of extending in a direction along the width direction of the curved portion of the substrate 4, and the in-plane array yarn y is folded in a state of extending in a direction orthogonal to the width direction of the curved portion of the substrate 4. Are arranged respectively. The bias yarn B is the in-plane array yarn x,
Arranged in a folded shape so as to form an angle of 45 ° with y,
Bias yarn layers arranged so that their intersecting directions are opposite to each other form a pair. Then, after the necessary number of the respective layers are laminated so that the in-plane array yarn y becomes the outermost layer, the fiber density of the woven fabric is increased and the thickness is adjusted, as shown in FIG. The pressure bar 8 is arranged outside the laminated yarn group 7 corresponding to the pressure bar 6, and the laminated yarn group 7 is compressed by the pressure bars 6 and 8. This compression operation can be performed not only when the arrangement of the in-plane arranged yarns x and y and the bias yarn B is all completed, but also when the yarn is arranged in small steps during the arrangement of the yarns, the variation in the fiber density is small and the density level can be increased. Therefore, it is preferable. After the compression of the laminated yarn group 7 by the pressure bars 6 and 8 is completed, the pipe 3 erected on the plane portion of the substrate 4 is replaced by the thickness direction yarn z, and the pipe 3 erected on the curved portion forms a fiber bundle. The layers are connected by being replaced by a resin-solidified rod zr.

When the pipe 3 and the thickness direction thread z are to be replaced, the pipe 3 located at the end of the substrate 4 is removed from the hole 4a and the laminated thread group 7, and the u-shaped pin 5 is pulled up, as shown in FIG. )
The thickness direction thread z in engagement with the u-pin 5 as shown in FIG.
Is pulled out in a loop above the laminated yarn group 7. Next, in order to prevent the loop portion of the thickness direction thread z that is replaced with the pipe 3 from coming off, insert the selvage yarn P into the loop portion and remove the u-shaped pin 5 as shown in FIG. Tighten the direction thread z. As a result, the thickness direction thread z is prevented from coming off, the loop portion is pulled, and the laminated thread group 7 is tightened in the thickness direction. Thereafter, similarly, the pipe 3 is sequentially replaced with the thickness direction thread z, and as shown in FIG. 4D, the respective thread layers forming the laminated thread group 7 in the flat portion are connected by the thickness direction thread z, and the pressure is applied. Even if the compressing action of the bars 6 and 8 is released, the bars 6 and 8 are kept at a predetermined thickness. In the portion corresponding to the flat portion of the substrate 4, the thickness direction yarn z having a function of bundling and binding the laminated yarn group 7 has an essential function for preventing delamination of each yarn layer and maintaining shape.

On the other hand, the in-plane array yarn y and the bias yarn B arranged in the portion corresponding to the curved portion of the substrate 4 are strained by the tension at the time of arrangement and pressed toward the substrate 4 side by the centripetal force toward the curvature center of the curved surface. Therefore, the thickness direction yarn z arranged in a folded shape having a function of bundling and binding the laminated yarn group 7 is not necessary even in a special compression operation. Then, instead of replacing the pipe 3 with the thickness direction thread z, the fiber bundle is replaced with a rod zr obtained by hardening a fiber bundle with resin.

The intervals of the pipes 3 standing on the flat surface of the substrate 4 are regular, and even when the pipes 3 are replaced by the thickness direction yarns z arranged in a folded manner, they can be uniformly processed, which facilitates the work. is there. On the other hand, since the curved portion has various shapes depending on the forming member, uniform processing cannot be performed, and replacement with the thickness direction thread z arranged in a folded shape is a complicated operation. However, the work of replacing the pipe 3 with the rod zr can be easily performed. In a three-dimensional woven fabric, since the number of curved portions is inevitably large because it is highly suitable as a block material for connecting members, there is a great advantage that the work for forming the curved portions is simplified.

(Embodiment 2) Next, another embodiment of the method for producing a three-dimensional fabric will be described with reference to FIG. This embodiment differs from the above-mentioned embodiments in the shape of the curved portion of the substrate 4 and in that the rod zr is provided upright in the curved portion instead of the pipe 3. That is, the pressure bar 6 is provided on the curved portion of the substrate 4.
The rod insertion parts 9 in the shape of a quarter arc are bulged and formed at predetermined intervals except the positions where the rods are arranged. One end of the rod zr in which the resin impregnated in the fiber bundle is semi-cured is inserted into the rod insertion parts 9. Fixed. When the rod insertion portion 9 is not bulged, the area of the curved portion of the substrate 4 into which the rod zr can be inserted is small and a large number of rods zr cannot be inserted, but the rod insertion portion 9 is bulged. Since it is formed to be protruded, a large number of rods zr can be inserted.

Then, with the pressure bar 6 placed on the substrate 4, the in-plane array yarns x and y and the bias yarn B are arranged on the end portion of the substrate 4 in the same manner as in the above embodiment. The x-yarn layer, the y-yarn layer, and the bias yarn layer are sequentially laminated so as to be folded back in the state of engaging with 3. After laminating the required number of each of the layers according to the required strength,
The pressure bar 8 is arranged on the laminated yarn group 7 to perform the compression operation of the laminated yarn group 7. After that, the pipe 3 erected on the flat portion of the substrate 4 is replaced with the thickness direction thread z as in the above-described embodiment. Since the rod zr of the fiber bundle is preliminarily set up on the curved portion of the substrate 4, the replacement work of the pipe 3 and the rod zr is not required unlike the above embodiment, and the production efficiency is remarkably improved. Rod zr forming the curved portion 2 of the three-dimensional fabric F
Is a composite material as it is, but the semi-cured resin impregnated in the fiber bundle is completely cured when the matrix resin of the composite material is cured, so that the binding force with the matrix resin is further improved.

The present invention is not limited to the above embodiment, and for example, as a method of replacing the pipe 3 and the thickness direction thread z, the u-shaped pin 5 is used to change the thickness direction thread z. Instead of the loop-shaped insertion and the selvage thread P retaining method, the pipe 3 is pushed out by the needle having the thickness direction thread z inserted in the needle hole and the needle is withdrawn to the opposite side of the laminated thread group 7, The operation of pushing the adjacent pipe 3 from the opposite side to the previous time may be repeated to insert the thickness direction thread z into the laminated thread group 7 in a zigzag shape, or a pin may be used instead of the pipe 3. Further, the inclination angle of the bias yarn B is set to other than 45 °, or one or both of the plate-like portions 1a and 1b of the three-dimensional woven fabric F is made to have five-axis orientation, but the bias yarn B is removed to have three-axis orientation. Alternatively, the bias yarns B forming the pair of bias yarn layers may be arranged so as to form an inclination angle of 60 ° with respect to the in-plane arranged yarn y, and the in-plane arranged yarn x may be omitted so as to have a four-axis orientation. May be. Further, the in-plane array yarns x and y and the bias yarn B forming each yarn layer may be formed of a plurality of yarns instead of being formed of one continuous yarn. Furthermore, the shape of the three-dimensional woven fabric F is not limited to the L-shape, and may be applied to other shapes such as a U-shape and a U-shape. In this case, as in the case of the L-shaped three-dimensional woven fabric, it can be manufactured by using a substrate having a corresponding shape to which a large number of pins or pipes are attached.

[0024]

As described above in detail, the three-dimensional woven fabric of the present invention has a three-dimensional shape in which a plurality of plate-like portions are joined together, such as a girder material having an L-shaped or U-shaped irregular cross section. When used as a skeleton material of a woven composite material, unlike a case where a conventional three-dimensional woven fabric is used, a joint portion (curved portion) of a plate portion where stress concentration is likely to occur is spread across a plurality of plate portions. Since there are yarns arranged so as to intersect with, the yarns contribute effectively to share the force in the direction of withstanding the stress acting on the joint portion, and the strength of the composite material is improved. When the yarns of the thickness direction component arranged in the thickness direction of the laminated yarn layers forming the curved portion are arranged in a non-folded manner, the yarns of the thickness direction component are arranged in a folded form. It is easier to manufacture compared to.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an arrangement state of in-plane array yarns and bias yarns.

FIG. 2 is a schematic perspective view of a three-dimensional fabric.

FIG. 3 is a perspective view showing a substrate used for manufacturing a three-dimensional fabric.

FIG. 4 is a schematic view showing a procedure of replacing the thickness direction thread z with a pipe.

FIG. 5 is a schematic cross-sectional view showing a positional relationship among a substrate, a pressure bar, a laminated yarn group, and a pipe.

FIG. 6 is a schematic cross-sectional view showing a positional relationship among a substrate, a pressure bar, a laminated yarn group, a rod and a pipe according to a second embodiment.

FIG. 7 is a schematic perspective view showing arrangement positions of a conventional three-dimensional fabric and a yarn guide tube.

FIG. 8 is a schematic perspective view showing another conventional example.

[Explanation of symbols]

1a, 1b ... Plate-shaped portion, 2 ... Curved portion, 3 ... Pipe, 4 ... Substrate, 7 ... Laminated yarn group, x ... In-plane arranged yarn, y ... In-plane arranged yarn,
z: thickness direction thread, B: bias thread as in-plane array thread,
P ... selvage yarn, F ... three-dimensional woven fabric, zr ... rod as yarn of thickness direction component.

Front Page Continuation (72) Inventor, Yasaya Mita, 2-chome, Toyota-cho, Kariya City, Aichi Prefecture Toyota Industries Corporation

Claims (1)

[Claims] 1. A plurality of plate-shaped portions are formed in a continuous shape via a curved portion, and each plate-shaped portion has at least two yarns constituting a component in its thickness direction laminated in multiple layers on the plate-shaped portion. A yarn layer made of in-plane arranged yarns, which are inserted in a folded shape so as to join the yarn layers made of yarns arranged in a direction, and the curved portion is arranged continuously over the adjacent plate-like portions. A three-dimensional woven fabric composed of yarns of thickness direction components arranged in a non-folded manner in the thickness direction of a curved portion.