Patent Description:
It has been known that there are, as a joint member of a composite, a fiber-reinforced composite member formed by collecting a plurality of fiber-reinforced rod members (for example, see <CIT>). Each of fiber-reinforced rod members is provided with a recessed part recessed with respect to an end surface, or a projecting part projecting from the end surface. The recessed part of a fiber-reinforced rod member is caused to abut against the projecting part of a fiber-reinforced rod member, and resin is injected into a space between the recessed part and the projecting part. In this manner, the fiber-reinforced rod members are joined.

<CIT> discloses joint members made of composite materials formed with projecting parts projecting from faces to be joined and in which reinforcing fibers are oriented along the direction orthogonal to the faces to be joined, and recessed parts recessed to the faces to be joined. The projecting parts are stored in the recessed parts, tip faces of the projecting parts are contacted with the recessed parts, the projecting parts and the recessed parts are softened by applying ultrasonic vibration thereto, and the composite materials are fused in such a manner that the projecting parts and the recessed parts are fitted.

<CIT> discloses a method for producing a vehicle component, comprising the method steps: introducing a fibre matrix semi-finished product with a thermosetting matrix into a mould, producing a bearing bush by pressing the fibre matrix semi-finished product, producing a fibre preform for a connecting strut, introducing the fibre preform into an injection mould, producing the connecting strut by impregnating the fibre preform with a thermosetting material which is injected into the injection mould for this purpose, and firmly connecting the connecting strut to the bearing bush. For this purpose, the bearing bush is produced with a connecting region comprising a connecting groove, the connecting groove being widened in a trapezoidal shape in an end region in the direction of the groove base. The connecting strut is also widened in a trapezoidal shape in an end region in the direction of its end face. For joining, the end region of the connecting strut is inserted into the connecting groove with the addition of adhesive, in such a way that the trapezoidally expanded end region of the connecting strut engages in the trapezoidally expanded end region of the connecting groove.

<CIT> discloses a hollow moulded part made from plastic material containing fibres has at least two hollow chambers between which at least one web is provided which bounds the hollow chambers together with outer wall parts. The hollow moulded part is a one piece pressed moulded part of a fibre compound plastic material containing endless fibres in a plastic material matrix.

A joined member in which composites are joined may be provided with a load, such as a tensile load, in a direction of tearing off the joined portion. In <CIT>, because the fiber-reinforced rod members are joined by injecting resin into a space between the recessed part and the projecting part, it is required to secure the joined state against the tensile load with adhesive force of the resin. However, in <CIT>- <CIT>, because use of an adhesive, such as resin, is required, dealing of the adhesive becomes complicated, such as implementation of pretreatment on the fiber-reinforced rod members. For this reason, to join the composites without using an adhesive, it is required to secure the joined state of composites against the tensile load by physically engaging the composites with each other. In this case, when fiber directions of the reinforcement fibers included in the composites coincide with a direction extending along the load direction, the reinforcement fibers of the composites become easily torn, and it becomes difficult to properly maintain the joined state of the composites.

For this reason, the present disclosure is aimed at providing a joint member of a composite and a joint structure capable of properly maintaining the joined state even when a load is provided.

A joint member according to the present invention has the features of claim <NUM>, <NUM> or <NUM>.

A joint structure according to the present invention has the features of claim <NUM> and includes a plurality of the joint members of a composite. The joint part of one of the joint members serves as the joining part, and the joint part of the other joint member is joined to the joint part of the one joint member.

The present disclosure enables proper maintenance of the joined state even when a load is provided.

The following is a detailed explanation of embodiments according to the present disclosure with reference to drawings. The present invention is not limited to the embodiments. The constituent elements described hereinafter can be appropriately combined, and the embodiments can be combined.

A joint structure <NUM> according to a first embodiment is a structure formed by joining a joint member of a composite to a joining part. The following embodiments illustrate the case where the joining part is also a joint member of a composite, and the two joint members of composites are joined. While the two joint members of the composites are joined in the following embodiments, the joining part may be formed of a material different from the composite and may be a metal joining part, for example. While the two joint members of composites are joined in the first embodiment, a plurality of joint members may be joined. For example, three or more joint members may be joined.

<FIG> is illustrates four orthogonal views of one of joint members forming a joint structure according to a first embodiment. <FIG> illustrates four orthogonal views of the other of the joint members forming the joint structure according to the first embodiment. <FIG> is an explanatory diagram illustrating joining between the one joint member and the other joint member of the joint structure according to the first embodiment. <FIG> is an explanatory diagram illustrating a state in which a tensile load is applied to the joint structure according to the first embodiment. <FIG> are diagrams schematically illustrating examples of orientation patterns of reinforcement fibers in joint parts.

As illustrated in <FIG>, the joint structure <NUM> includes one joint member <NUM> (hereinafter also simply referred to as "joint member <NUM>") and the other joint member <NUM> (hereinafter also simply referred to as "joint member <NUM>"). The composite includes resin and reinforcement fibers. For example, thermosetting resin, thermoplastic resin, or the like is used as the resin, and carbon fibers, glass fibers, aramid fibers, or the like are used as the reinforcement fibers. In the first embodiment, carbon fiber-reinforced plastics (CFRP) are used as the composite. As illustrated in <FIG>, a tensile load is applied to the joint structure <NUM>, for example, in a direction in which one joint member <NUM> and the other joint member <NUM> are separated from each other.

<FIG> illustrates one joint member <NUM>. The joint member <NUM> includes a main body part <NUM> and a joint part <NUM> connecting with the main body part <NUM> and to be joined to the other joint member <NUM>. The main body part <NUM> is formed in a square tube shape with one direction serving as a longitudinal direction. Specifically, the main body part <NUM> has a hollow structure with an inside having a square tube shape. One end part in the longitudinal direction of the main body part <NUM> is provided with the joint part <NUM>.

The joint part <NUM> is formed in a projecting shape projecting from the main body part <NUM> outward in the longitudinal direction. Specifically, the joint part <NUM> includes two joining surfaces <NUM> and two projecting parts <NUM> projecting from the respective joining surfaces <NUM>. The two joining surfaces <NUM> are inclined toward the other end side in the longitudinal direction as it extends toward the outside, with the center line of the joint part <NUM> serving as the boundary, in a horizontal plane orthogonal to the longitudinal direction, and have a mountain shape. The two projecting parts <NUM> serve as projections projecting toward the outside in the longitudinal direction, with respect to the two inclined joining surfaces <NUM>. The projecting parts <NUM> project toward respective recessed parts <NUM> described later. Each of the two projecting parts <NUM> is formed to have a short length (narrow width) in the width direction orthogonal to the longitudinal direction, on the base end side in the longitudinal direction, and have a long length (broad width) in the width direction, on the tip side in the longitudinal direction. For this reason, each of the projecting parts <NUM> is provided with a bulging part 16a bulging toward the recessed part <NUM> in the longitudinal direction (load direction) opposed to the recessed part <NUM> described later. In addition, in a horizontal plane orthogonal to the longitudinal direction, the tip side of each of the two projecting parts <NUM> is formed to have a short length (narrow width) on one side (lower side in <FIG>) in a horizontal direction, and have a long length (broad width) on the other side (upper side in <FIG>) in the horizontal direction. As described above, the projecting parts <NUM> provided with the bulging parts 16a have a dovetail shape.

<FIG> illustrates the other joint member <NUM>. In the same manner as the joint member <NUM>, the joint member <NUM> includes a main body part <NUM> and a joint part <NUM> connecting with the main body part <NUM> and to be joined to the joint part <NUM> of the joint member <NUM>. The main body part <NUM> of the joint member <NUM> is the same as the main body part <NUM> of the joint member <NUM>, and an explanation thereof will be omitted.

The joint part <NUM> is formed in a recessed shape recessed inward from the main body part <NUM> in the longitudinal direction, and in a complementary shape to the joint part <NUM> of the joint member <NUM>. Specifically, the joint part <NUM> includes two joining surfaces <NUM> and two recessed parts <NUM> recessed with respect to the respective joining surfaces <NUM>. The two joining surfaces <NUM> are inclined toward one end side in the longitudinal direction as it extends toward the outside, with the center line of the joint part <NUM> serving as the boundary, in a horizontal plane orthogonal to the longitudinal direction, and have a valley shape. The two recessed parts <NUM> serve as grooves recessed toward the inside in the longitudinal direction, with respect to the two inclined joining surfaces <NUM>. The recessed parts <NUM> are recessed toward a side opposite to the projecting parts <NUM>. Each of the two recessed parts <NUM> is formed to have a short length (narrow width) in the width direction orthogonal to the longitudinal direction, on the opening end side in the longitudinal direction, and have a long length (broad width) in the width direction, on the bottom end side in the longitudinal direction. For this reason, each of the recessed parts <NUM> is provided with a bulging part 26a bulging toward the projecting part <NUM> in the longitudinal direction (load direction) opposed to the projecting part <NUM>. In addition, in a horizontal plane orthogonal to the longitudinal direction, the bottom end side of each of the two recessed parts <NUM> is formed to have a short length (narrow groove width) on one side (lower side in <FIG>) in the horizontal direction, and have a long length (broad groove width) on the other side (upper side in <FIG>) in the horizontal direction. As described above, the recessed parts <NUM> provided with the bulging parts 26a have a dovetail shape (dovetail groove).

The joint member <NUM> and the joint member <NUM> as described above are formed using, for example, a three-dimensional molding device. In the case of molding the joint members <NUM> and <NUM>, unit layers are each formed using a composite including resin and fibers, and the unit layers are laid up to form a laminate. The joint member <NUM> and the joint member <NUM> may be molded by, for example, injection molding. In the case of molding the joint members <NUM> and <NUM> by injection molding, it is required to adopt the shapes of the joint members <NUM> and <NUM> enabling injection molding, and use reinforcement fibers enabling formation of an anisotropic orientation pattern described later (for example, <FIG>).

In the joint member <NUM> and the joint member <NUM> formed described above, the fitting direction in which the joint part <NUM> is relatively moved with respect to the joint part <NUM> to join the joint parts <NUM> and <NUM> is a direction different from the load direction, as illustrated in <FIG>. Specifically, the fitting direction of the joint parts <NUM> and <NUM> is an in-plane direction of one pair of overlapping joining surfaces <NUM> and <NUM>. The one pair of joining surfaces <NUM> and <NUM> herein are a pair of the joining surfaces <NUM> and <NUM> that are respectively provided with the projecting part <NUM> and the recessed part <NUM> that are narrow on the center line side in the horizontal plane orthogonal to the longitudinal direction. For this reason, the joint parts <NUM> and <NUM> have shapes allowing relative movement in the fitting direction.

The following describes orientation patterns of reinforcement fibers in the projecting parts <NUM> of the joint part <NUM> and the recessed parts <NUM> of the joint part <NUM> with reference to <FIG>. The orientation patterns of the reinforcement fibers illustrated in <FIG> have anisotropy (anisotropic property) in which the fiber directions of the reinforcement fibers include a fiber direction different from the load direction.

<FIG> illustrates an orientation pattern in which the reinforcement fibers are provided along the external shapes of the joint parts <NUM> and <NUM>, and the reinforcement fibers are wound toward the inside of the joint parts <NUM> and <NUM>. Specifically, in <FIG>, the reinforcement fibers included in the projecting part <NUM> of the joint part <NUM> includes reinforcement fibers formed in such a manner of circling along the external shape of the projecting part <NUM> having the bulging part 16a, and reinforcement fibers wound and provided inside the reinforcement fibers extending along the external shape. In the same manner, the reinforcement fibers included in the recessed part <NUM> of the joint part <NUM> include reinforcement fibers formed in such a manner of circling along the external shape of the recessed part <NUM> having the bulging part 26a, and reinforcement fibers wound and provided inside the reinforcement fibers extending along the external shape. For this reason, the orientation pattern of the reinforcement fibers of the projecting part <NUM> and the recessed part <NUM> illustrated in <FIG> have anisotropy. In addition, even when the tensile load is applied in a direction (longitudinal direction) in which the joint parts <NUM> and <NUM> are separated from each other, the orientation pattern has anisotropy capable of enduring the tensile load, because the fiber directions of the reinforcement fibers in the bulging parts 16a and 26a cross the load direction.

<FIG> illustrates an orientation pattern in which a plurality of layers of reinforcement fibers are laid up and the fiber directions of each layer are aligned in one direction. Specifically, the reinforcement fiber layers include a layer (the left layer in <FIG>) having a fiber direction that coincides with a direction orthogonal to the load direction. In the case of forming the joint parts <NUM> and <NUM> only of the layer illustrated in the left part of <FIG>, delamination may occur on the base end side of the projecting part <NUM>, although it can endure the tensile load in the bulging parts 16a and 26a. For this reason, the reinforcement fiber layers may include a layer (the right layer in <FIG>) having a fiber direction that coincides with a direction extending along the load direction. In this state, regardless of the ratio of the layer illustrated in the left part of <FIG> to the layer illustrated in the right part of <FIG>, the orientation pattern of the reinforcement fibers of the projecting part <NUM> and the recessed part <NUM> illustrated in <FIG> has anisotropy. In addition, even when the tensile load is applied in the direction (longitudinal direction) in which the joint parts <NUM> and <NUM> are separated from each other, the orientation pattern has anisotropy capable of enduring the tensile load, because the fiber directions of the reinforcement fibers in the bulging parts 16a and 26a cross the load direction.

<FIG> illustrates an orientation pattern in which discontinuous reinforcement fibers including thermoplastic resin are oriented intentionally. Specifically, in <FIG>, the reinforcement fibers included in the projecting part <NUM> of the joint part <NUM> are scattered in the bulging part 16a on both sides in the width direction of the projecting part <NUM> and extend along the load direction in parts other than the bulging part 16a in the center in the width direction of the projecting part <NUM>. For this reason, the orientation pattern of the reinforcement fibers of the projecting part <NUM> and the recessed part <NUM> illustrated in <FIG> has anisotropy. In addition, even when the tensile load is applied in the direction (longitudinal direction) in which the joint parts <NUM> and <NUM> are separated from each other, the orientation pattern has anisotropy capable of enduring the tensile load, because the reinforcement fibers in the bulging parts 16a and 26a have fiber directions scattered with respect to the load direction.

As described above, according to the first embodiment, the joint parts <NUM> and <NUM> include the bulging parts 16a and 26a bulging toward the opposed joint parts <NUM> and <NUM>, in the opposed direction (longitudinal direction) in which the joint parts <NUM> and <NUM> are opposed to each other, and have an orientation pattern having anisotropy such that the fiber directions of the reinforcement fibers included in the joint parts <NUM> and <NUM> include a direction different from the load direction of the load applied to a joined portion between the joint parts <NUM> and <NUM>. This structure hinders occurrence of damage, such as breakage, in the bulging parts 16a and 26a of the joint parts <NUM> and <NUM>, even when a load is applied in the longitudinal direction, and enables proper maintenance of the joined state of the joint members <NUM> and <NUM>.

In addition, according to the first embodiment, the joint part <NUM> includes the projecting part <NUM> projecting toward the joint part <NUM>, and the bulging part 16a of the projecting part <NUM> bulges outward toward the joint part <NUM>. Even the joint part <NUM> including the projecting part <NUM> described above hinders occurrence of damage, such as breakage, in the bulging parts 16a, and thereby the joined state of the joint members <NUM> and <NUM> can be maintained properly.

In addition, according to the first embodiment, the joint part <NUM> includes the recessed part <NUM> recessed toward the side opposite to the joint part <NUM>, and the bulging part 26a of the recessed part <NUM> bulges outward toward the joint part <NUM>. Even the joint part <NUM> including the recessed parts <NUM> as described above hinders occurrence of damage, such as breakage, in the bulging parts 26a, and thereby the joined state of the joint members <NUM> and <NUM> can be maintained properly.

In addition, according to the first embodiment, the joint parts <NUM> and <NUM> have an orientation pattern in which reinforcement fibers are provided along the external shapes of the joint parts <NUM> and <NUM> and the reinforcement fibers are wound toward the inside of the joint parts <NUM> and <NUM>, as the orientation pattern having anisotropy. This structure enables increase in tensile strength in the bulging parts 16a and 26a of the joint parts <NUM> and <NUM>.

In addition, according to the first embodiment, the joint parts <NUM> and <NUM> have an orientation pattern in which a layer having a fiber direction extending along the load direction and a layer having a fiber direction crossing the load direction are laid up, as the orientation pattern having anisotropy. This structure simplifies the fiber orientation in the joint parts <NUM> and <NUM> and enables easy formation of an orientation pattern having anisotropy.

In addition, according to the first embodiment, the joint parts <NUM> and <NUM> have an orientation pattern in which discontinuous reinforcement fibers have fiber directions scattered in the bulging parts 16a and 26a, as the orientation pattern having anisotropy. This structure simplifies the fiber orientation in the bulging parts 16a and 26a and enables easy formation of an orientation pattern having anisotropy.

In addition, according to the first embodiment, each of the main body parts <NUM> and <NUM> has a hollow structure. This structure enables reduction in weight of the joint members <NUM> and <NUM>.

In addition, according to the first embodiment, the fitting direction to join the joint parts <NUM> and <NUM> is a direction different from the load direction, and each of the joint parts <NUM> and <NUM> has a shape allowing movement in the fitting direction. This structure enables proper maintenance of the joined state of the joint members <NUM> and <NUM> without release of fitting of the joint members <NUM> and <NUM>, even when a load is applied in the load direction.

The following describes a joint structure <NUM> according to a second embodiment, with reference to <FIG>. To avoid overlapping descriptions, the second embodiment describes parts different from those of the first embodiment, and parts having the same structures as those of the first embodiment will be described with the same reference numerals. <FIG> is a diagram schematically illustrating part of the joint structure according to the second embodiment.

The joint structure <NUM> according to the second embodiment has a structure in which the joint member <NUM> having recessed parts <NUM> is provided with energy directors <NUM> on external surfaces (front surfaces) of the joining surfaces <NUM> and the recessed parts <NUM>. The energy director <NUM> includes resin and is molten by friction with the projecting parts <NUM> by vibration using ultrasonic waves or the like. In the state in which the joint member <NUM> is fitted with the joint member <NUM>, when the joint member <NUM> and the joint member <NUM> relatively vibrate, the energy directors <NUM> are molten to form a welding layer <NUM>, and the joint part <NUM> of the joint member <NUM> is welded to the joint part <NUM> of the joint member <NUM>.

As described above, according to the second embodiment, the joint part <NUM> of the joint member <NUM> can be welded to the joint part <NUM> of the joint member <NUM>. This structure further strengthens joining between the joint members <NUM> and <NUM>.

While the joint member <NUM> including the recessed parts <NUM> is provided with the energy directors <NUM> in the second embodiment, the joint member <NUM> including the projecting parts <NUM> may be provided with the energy directors <NUM>, and the structure is not limited thereto.

In addition, while the energy directors <NUM> are provided in order to further strengthen joining between the joint members <NUM> and <NUM> in the second embodiment, the structure is not limited thereto. For example, a volume-increase adhesive may be used, and the adhesive may be injected into a space between the joint part <NUM> of the joint member <NUM> and the joint part <NUM> of the joint member <NUM> to form an adhesive layer between the joint part <NUM> of the joint member <NUM> and the joint part <NUM> of the joint member <NUM>. As another example, the joint members <NUM> and <NUM> may be joined by shrink fit in which the joint members <NUM> and <NUM> are cooled and shrunk and then the joint part <NUM> of the joint member <NUM> is fitted with the joint part <NUM> of the joint member <NUM>.

The following describes a joint structure <NUM> according to a third embodiment, with reference to <FIG>. To avoid overlapping descriptions, the third embodiment also describes parts different from those of the first and the second embodiments, and parts having the same structures as those of the first and the second embodiments will be described with the same reference numerals. <FIG> is a diagram schematically illustrating part of the joint structure according to the third embodiment.

The joint structure <NUM> according to the third embodiment has a structure in which the shapes of the projecting parts <NUM> and the recessed parts <NUM> of the joint member <NUM> and the joint member <NUM> are different from the shapes thereof in the first embodiment. Each of the projecting parts <NUM> is provided with a plurality of auxiliary projecting parts <NUM> projecting from the projecting part <NUM>. In addition, each of the recessed parts <NUM> having shapes complementary to the respective projecting parts <NUM> is provided with a plurality of auxiliary recessed parts <NUM> recessed from the recessed part <NUM>. The projecting parts <NUM> and the recessed parts <NUM> have fractal shapes.

As described above, in the third embodiment, the projecting parts <NUM> of the joint member <NUM> are provided with the auxiliary projecting parts <NUM>, and the recessed parts <NUM> of the joint member <NUM> are provided with the auxiliary recessed parts <NUM>. This structure further strengthens joining between the joint members <NUM> and <NUM>.

The following describes a joint structure <NUM> according to a fourth embodiment, with reference to <FIG>. To avoid overlapping descriptions, the fourth embodiment also describes parts different from those of the first to the third embodiments, and parts having the same structures as those of the first to the third embodiments will be described with the same reference numerals. <FIG> is a diagram schematically illustrating the joint structure according to the fourth embodiment.

The joint structure <NUM> according to the fourth embodiment further includes, in addition to the joint structure <NUM> according to the first embodiment, positioning pins <NUM> serving as positioning members determining the positions of the joint part <NUM> of the joint member <NUM> and the joint part <NUM> of the joint member <NUM> that are joined.

Each of the positioning pins <NUM> has a cylindrical shape and is provided so as to penetrate through the joint member <NUM> and the joint member <NUM> that are joined. The joint part <NUM> of the joint member <NUM> is provided with through holes <NUM> through which the positioning pins <NUM> are inserted. In the same manner, the joint part <NUM> of the joint member <NUM> is provided with through holes <NUM> through which the positioning pins <NUM> are inserted. The through holes <NUM> and <NUM> are formed to be aligned in the through direction when the joint members <NUM> and <NUM> are joined. The through holes <NUM> are formed, for example, in the projecting parts <NUM> of the joint part <NUM> so as to penetrate the projecting parts <NUM> in a direction orthogonal to the load direction and the fitting direction. In the same manner, the through holes <NUM> are formed, for example, in the recessed parts <NUM> of the joint part <NUM> so as to penetrate the recessed parts <NUM> in the direction orthogonal to the load direction and the fitting direction.

As described above, the structure of the fourth embodiment further includes the positioning pins <NUM> determining the positions of the joint part <NUM> of the joint member <NUM> and the joint part <NUM> of the joint member <NUM> that are joined. This structure further strengthens joining between the joint members <NUM> and <NUM>.

The following describes a joint structure <NUM> according to a fifth embodiment, with reference to <FIG>. To avoid overlapping descriptions, the fifth embodiment also describes parts different from those of the first to the fourth embodiments, and parts having the same structures as those of the first to the fourth embodiments will be described with the same reference numerals. <FIG> is a diagram schematically illustrating part of the joint structure according to the fifth embodiment.

The joint structure <NUM> according to the fifth embodiment has a structure in which the joint member <NUM> and the joint member <NUM>, that is, the main body parts <NUM> and <NUM> and the joint parts <NUM> and <NUM>, have a framed structure formed of a plurality of frame members <NUM>. The frame members <NUM> are formed to extend in the longitudinal direction and formed of a composite having a fiber direction of the reinforcement fibers that coincides with the longitudinal direction. In addition, the frame members <NUM> include frame members <NUM> having the longitudinal direction that coincides with the load direction, and frame members <NUM> having the longitudinal direction that coincides with a direction orthogonal to the load direction. The frame members <NUM> are arranged to have a lattice structure. The frame members <NUM> may be arranged to have a truss structure.

The frame members <NUM> have an orientation pattern having anisotropy in the joint parts <NUM> and <NUM>. Specifically, in the frame members <NUM>, the proportion of frame members <NUM> having the longitudinal direction that coincides with the load direction is different from the proportion of frame members <NUM> having the longitudinal direction that coincide with a direction orthogonal to the load direction. For example, in the frame members <NUM>, the proportion of the frame members <NUM> having the longitudinal direction that coincides with a direction orthogonal to the load direction are greater than that of the frame members <NUM> having the longitudinal direction that coincides with the load direction. The physical quantity to be used to obtain the proportion may be the total length of the frame members <NUM>, the total volume of the frame members <NUM>, or the total weight of the frame members <NUM>.

As described above, according to the fifth embodiment, the main body parts <NUM> and <NUM> and the joint parts <NUM> and <NUM> have a framed structure formed of a plurality of frame members <NUM>, and the joint parts <NUM> and <NUM> have an orientation pattern in which the reinforcement fibers are provided along the longitudinal direction of the frame members <NUM>, as the orientation pattern having anisotropy. This structure hinders occurrence of damage to the joint parts <NUM> and <NUM> even when a load is applied in the longitudinal direction and enables proper maintenance of the joined state of the joint members <NUM> and <NUM>. In addition, because the joint structure <NUM> acquired by joining the joint members <NUM> and <NUM> has a framed structure, a strong structure can be formed by uniting the matrix formed of resin, concrete, or the like.

The following describes a joint structure <NUM> according to a sixth embodiment, with reference to <FIG> and <FIG>. To avoid overlapping descriptions, the sixth embodiment also describes parts different from those of the first to the fifth embodiments, and parts having the same structures as those of the first to the fifth embodiments will be described with the same reference numerals. <FIG> is a perspective view illustrating the joint structure according to the sixth embodiment. <FIG> is an explanatory diagram illustrating joining between one joint member and the other joint member of the joint structure according to the sixth embodiment.

The joint structure <NUM> according to the sixth embodiment has a structure in which joint members <NUM> and <NUM> each having a T-shaped longitudinal section are joined. In the same manner as the first embodiment, the joint structure <NUM> according to the sixth embodiment is provided with a tensile load in a direction in which one joint member <NUM> and the other joint member <NUM> are separated from each other.

The joint member <NUM> includes a main body part <NUM> and a joint part <NUM> connecting with the main body part <NUM> and to be joined to the other joint member <NUM>. The main body part <NUM> is formed to extend in the longitudinal direction and formed in a T shape formed of a flange 81a and a rib part 81b in a section taken with a plane orthogonal to the longitudinal direction. The rib part 81b projects outward from the center in the width direction of the flange 81a. The inside of the main body part <NUM> has a hollow structure. One end part in the longitudinal direction of the main body part <NUM> is provided with the joint part <NUM>.

As illustrated in <FIG>, the joint part <NUM> is formed as a joint including a projecting part <NUM> and a recessed part <NUM> having a dovetail shape, and the projecting part <NUM> and the recessed part <NUM> in the joint part <NUM> are formed to extend in an oblique direction connecting the flange 81a and the rib part 81b, in a plane orthogonal to the load direction (longitudinal direction). For this reason, the projecting part <NUM> and the recessed part <NUM> of the joint part <NUM> are formed such that part of them is discontinuous. The shapes of the projecting part <NUM> and the recessed part <NUM> are dovetail shapes in the same manner as the first embodiment and include bulging parts.

Like the joint member <NUM>, the joint member <NUM> includes a main body part <NUM> and a joint part <NUM> connecting with the main body part <NUM> and to be joined to the other joint member <NUM>. The main body part <NUM> of the joint member <NUM> is formed in a T shape formed of a flange 91a and a rib part 91b, in the same manner as the main body part <NUM> of the joint member <NUM>, and an explanation thereof will be omitted.

As illustrated in <FIG>, the joint part <NUM> is formed as a joint formed of a projecting part <NUM> and a recessed part <NUM> having a dovetail shape, and the projecting part <NUM> and the recessed part <NUM> in the joint part <NUM> are formed to extend in an oblique direction connecting the flange 91a and the rib part 91b, in a plane orthogonal to the load direction (longitudinal direction). For this reason, like the joint member <NUM>, the projecting part <NUM> and the recessed part <NUM> of the joint part <NUM> are formed such that part of them is discontinuous. The shapes of the projecting part <NUM> and the recessed part <NUM> are dovetail shapes in the same manner as the first embodiment and include bulging parts.

In the joint member <NUM> and the joint member <NUM> formed described above, the fitting direction in which the joint part <NUM> is relatively moved with respect to the joint part <NUM> to join the joint parts <NUM> and <NUM> is a direction different from the load direction, as illustrated in <FIG>. Specifically, the fitting direction of the joint parts <NUM> and <NUM> coincides with the oblique direction in which the projecting parts <NUM> and <NUM> and the recessed parts <NUM> and <NUM> extend. In this state, because part of the projecting parts <NUM> and <NUM> and the recessed parts <NUM> and <NUM> is formed discontinuous, when the joint members <NUM> and <NUM> are joined, for example, the projecting part <NUM> in the hatched portion illustrated in <FIG> is fitted across the discontinuous recessed part <NUM> in the hatched portion.

As described above, according to the sixth embodiment, the joined state of the joint members <NUM> and <NUM> can be maintained properly, even when the joint member <NUM> and the joint member <NUM> have T shapes formed of the flanges 81a and 91a and the rib parts 81b and 91b.

The following describes a joint structure <NUM> according to a seventh embodiment, with reference to <FIG>. To avoid overlapping descriptions, the seventh embodiment also describes parts different from those of the first to the sixth embodiments, and parts having the same structures as those of the first to the sixth embodiments will be described with the same reference numerals. <FIG> is a perspective view illustrating the joint structure according to the seventh embodiment.

The joint structure <NUM> according to the seventh embodiment is acquired by joining three joint members. As illustrated in <FIG>, the joint structure <NUM> includes a joint member <NUM>, a joint member <NUM>, and a joint member <NUM>.

The joint member <NUM> and the joint member <NUM> are acquired by forming a joint part <NUM> and a joint part <NUM> in the joint member <NUM> and the joint member <NUM> of the sixth embodiment, respectively. Specifically, the joint member <NUM> includes a main body part <NUM>, a joint part <NUM> connecting with the main body part <NUM> and to be joined to the joint member <NUM>, and the joint part <NUM> connecting with the main body part <NUM> and to be joined to the joint member <NUM>. The main body part <NUM> and the joint part <NUM> are the same as the main body part <NUM> and the joint part <NUM> of the joint member <NUM> according to the sixth embodiment, and an explanation thereof will be omitted. The joint part <NUM> is formed in a plane opposed to the joint member <NUM>. The joint part <NUM> is formed as a joint including a projecting part and a recessed part having dovetail shapes, and formed to extend in a direction different from the load direction (longitudinal direction) and the fitting direction of fitting with the joint member <NUM>. The shapes of the projecting part and the recessed part of the joint part <NUM> are dovetail shapes in the same manner as the first embodiment and have bulging parts.

The joint member <NUM> includes a main body part <NUM>, a joint part <NUM> connecting with the main body part <NUM> and to be joined to the joint member <NUM>, and the joint part <NUM> connecting with the main body part <NUM> and to be joined to the joint member <NUM>. The main body part <NUM> and the joint part <NUM> are the same as the main body part <NUM> and the joint part <NUM> of the joint member <NUM> according to the sixth embodiment, and an explanation thereof will be omitted. The joint part <NUM> is formed in a plane opposed to the joint member <NUM>. The joint part <NUM> is formed as a joint formed of a projecting part and a recessed part having dovetail shapes, and formed to extend in a direction different from the load direction (longitudinal direction) and the fitting direction of fitting with the joint member <NUM>. The shapes of the projecting part and the recessed part of the joint part <NUM> are dovetail shapes in the same manner as the first embodiment and have bulging parts. In addition, the projecting part and the recessed part of the joint part <NUM> and the projecting part and the recessed part of the joint part <NUM> are formed to be continuous in the extending direction.

The joint member <NUM> includes a main body part <NUM> and a joint part <NUM> connecting with the main body part <NUM> and to be joined to the joint member <NUM> and the joint member <NUM>. The main body part <NUM> is formed in a flat plate shape. The joint part <NUM> is formed in a plane opposed to the joint member <NUM> and the joint member <NUM> to be joined. The joint part <NUM> is formed as a joint formed of a projecting part and a recessed part having dovetail shapes, and formed to extend in a direction different from the load direction (longitudinal direction), the fitting direction of fitting with the joint member <NUM>, and the fitting direction of fitting with the joint member <NUM>. The shapes of the projecting part and the recessed part of the joint part <NUM> are dovetail shapes in the same manner as the first embodiment, and have bulging parts.

The joint member <NUM>, the joint member <NUM>, and the joint member <NUM> formed as described above are joined such that, first, the joint member <NUM> and the joint member <NUM> are joined, and thereafter the joint member <NUM> is joined to the joint member <NUM> and the joint member <NUM>. In the joining, the fitting direction of the joint member <NUM> and the joint member <NUM> is different from the fitting direction of the joint member <NUM> and the joint members <NUM> and <NUM>, and the fitting directions are also different from the load direction.

As described above, according to the seventh embodiment, even when the three joint members <NUM>, <NUM>, and <NUM> are joined, the joint member <NUM> can be provided with two joint parts <NUM> and <NUM>, the joint member <NUM> can be provided with two joint parts <NUM> and <NUM>, and the fitting directions corresponding to the joint parts can be set in mutually different directions. Thus, in the case of joining the three joint members <NUM>, <NUM>, and <NUM>, the joined state of the joint members <NUM>, <NUM>, and <NUM> can be maintained properly even when a load, such as a tensile load, is applied.

The joint members and the joint structures described in the embodiments are understood, for example, as follows.

The joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to a first aspect are joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite including reinforcement fibers and resin and joined to joining parts (joint parts) <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. The joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> include the main body parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> and the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> connecting with the main body parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> and to be joined to the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. The joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> include bulging parts 16a and 26a bulging toward the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> in an opposed direction in which the joint parts are opposed to the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, and have an orientation pattern having anisotropy such that the fiber directions of the reinforcement fibers included in the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> include fiber directions different from the load direction of a load applied to a joined portion of the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> and the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

This structure enables to exhibit high tensile strength in the bulging parts 16a and 26a of the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

In the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to a second aspect, the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> are projections (projecting parts) <NUM> and <NUM> projecting toward the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, and the bulging parts 16a and 26a of the projections <NUM> and <NUM> bulge outward toward the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

This structure enables to exhibit higher tensile strength in the bulging parts 16a and 26a of the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

In the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to a third aspect, the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> are grooves (recessed parts) <NUM> and <NUM> recessed in a direction opposite to the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, and the bulging parts 16a and 26a of the grooves <NUM> and <NUM> narrow inward toward the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

In the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to a fourth aspect, the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> have an orientation pattern in which the reinforcement fibers are provided along the external shape of the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> and the reinforcement fibers are wound toward the inside of the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, as the orientation pattern having anisotropy.

In the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to a fifth aspect, the reinforcement fibers have fiber directions each of which is aligned in one direction, and the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> have an orientation pattern in which a layer having a fiber direction extending along the load direction and a layer having a fiber direction crossing the load direction are laid up, as the orientation pattern having anisotropy.

This structure simplifies the fiber orientations in the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> and enables easy formation of the orientation pattern having anisotropy.

In the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to a sixth aspect, the reinforcement fibers are discontinuous reinforcement fibers, and the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> have an orientation pattern in which the reinforcement fibers have fiber directions scattered in the bulging parts 16a and 26a, as the orientation pattern having anisotropy.

This structure simplifies the fiber orientation in the bulging parts 16a and 26a and enables easy formation of the orientation pattern having anisotropy.

In the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to a seventh aspect, each of the main body parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> has a hollow structure.

This structure enables reduction in weight of the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

In the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to an eighth aspect, each of the main body parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> and the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> has a framed structure formed of a plurality of frame members <NUM>, and the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> have an orientation pattern in which the reinforcement fibers are provided along the longitudinal direction of the frame members <NUM>, as the orientation pattern having anisotropy.

This structure hinders occurrence of damage to the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> even when a load is applied in the longitudinal direction, and thus enables proper maintenance of the joined states of the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. In addition, because the joint structures <NUM> acquired by joining the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> have a framed structure, strong structures can be formed by uniting the matrix formed of resin, concrete, or the like.

In the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to a ninth aspect, the fitting direction in which the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> are moved with respect to the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> to join the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> to the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, is a direction different from the load direction, and the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> have a shape allowing movement in the fitting direction with respect to the joining parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

This structure enables proper maintenance of the joined states of the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> without releasing the fitting of the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, even when a load is applied in the load direction.

In the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite according to a tenth aspect, a plurality of the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> are provided, and fitting directions corresponding to the plurality of the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> are mutually different directions.

This structure enables proper maintenance of the joined states of the joint members <NUM>, <NUM>, and <NUM>, in the case of joining the joint members <NUM>, <NUM>, and <NUM>, even when a load is applied in the load direction.

The joint structures <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> according to an eleventh aspect include a plurality of the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of a composite; the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> of one joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> serves as the joining part; and the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of the other joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> is joined to the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of the one joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>.

This structure hinders occurrence of damage, such as breakage, in the bulging parts 16a and 26a of the joint parts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> even when a load is applied in the longitudinal direction, and enables proper maintenance of the joined states of the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

In the joint structures <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> according to a twelfth aspect, the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of one joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> is welded to the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of the other joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>.

This structure enables welding of the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of one joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> to the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of the joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>. This structure further strengthens joining between the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

The joint structures <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> according to a thirteenth aspect further includes an adhesive layer between the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of one joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> and the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of the other joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>.

This structure further strengthens joining of the joint members <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

The joint structures <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> according to a fourteenth aspect further includes a positioning member (positioning pins <NUM>) determining positions of the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of one joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> and the joint part <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> of the other joint member <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM> that are joined.

Claim 1:
A joint member (<NUM>;<NUM>) configured to be joined with another joint member to form a joint structure capable of enduring/receiving a tensile load in a load direction in which the joint member (<NUM>;<NUM>) and the other joint member are separated from each other at a joined portion of the joint structure in a longitudinal direction of the joint member (<NUM>; <NUM>),
wherein the joint member (<NUM>;<NUM>) is formed of a composite including reinforcement fibers and resin and comprises a main body part (<NUM>;<NUM>) and a joint part (<NUM>;<NUM>) connected with the main body part (<NUM>;<NUM>) at an end part of the main body part (<NUM>;<NUM>) in the longitudinal direction of the joint member (<NUM>; <NUM>),
wherein the joint part (<NUM>;<NUM>) includes either projecting parts (<NUM>) provided with bulging parts (16a) to form a dovetail shape or recessed parts (<NUM>) provided with bulging parts (26a) to form a dovetail groove and configured to be joined to a joint part in a complementary shape of the other joint member to endure/receive the tensile load in the longitudinal direction,
wherein the joint part (<NUM>;<NUM>) has an orientation pattern having anisotropy such that fiber directions of the reinforcement fibers included in the joint part (<NUM>;<NUM>) include a fiber direction different from the load direction, and
characterized in that,
the joint part (<NUM>;<NUM>) has an orientation pattern in which the reinforcement fibers are provided along an external shape of the joint part (<NUM>;<NUM>) and the reinforcement fibers are wound toward an inside of the joint part (<NUM>;<NUM>).