JP2003328498A - Strengthening member, trussed structure and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a strengthening member reducing cost and weight, a trussed structure and a manufacturing method for the strengthening member. <P>SOLUTION: The strengthening member having each rod end 1 and a fiber- reinforced plastic hollow structure 2 converging towards both end sections 2a and having female screw sections 2b at both end sections 2a of the hollow structure 2 is adopted. In the manufacturing method for the strengthening member, a manufacturing method through a base-material manufacturing method, a resin impregnation process, an abutting-member mounting process and a rod-end mounting process is adopted. The trussed structure using the strength member is adopted. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention is arranged between members,
The present invention relates to a strength member that transmits a load between these members, a method of manufacturing the strength member, and a truss structure using the strength member. In particular, it relates to a light and low-cost strength member, truss structure, and method for manufacturing a strength member.

[0002]

2. Description of the Related Art For example, in an aerospace truss structure such as a fuel tank support structure for a space rocket or a construction structure such as general building materials, a truss structure which is lightweight but can exhibit relatively high strength is widely used. . As a strength member used for a component of this type of truss structure, for example, in a general building material, a metal pipe is generally welded or bolted with end fittings at both ends. In aerospace truss structures, weight reduction is required, so instead of metal pipes, CFRP (fiber reinforced plastic) tubes are used, and metal (for example, aluminum) end fittings are attached to both ends of the fasteners. The combined one is adopted.

Although not shown, this fastener connection is not shown.
For a cylindrical CFRP tube with both ends open, after reinforcing each of the openings with another CFRP ring, the end fittings are fitted to the reinforcing parts, and the end fittings and the wall surfaces of the reinforcing parts are simultaneously formed. It has a structure in which it is fastened with multiple fasteners that penetrate it. Since the end fittings forming the end of the strength member manufactured in this way are pre-threaded, the male thread of the rod end (eyebolt) is screwed onto the end fitting, thereby It is a strength member that can connect the parts via these rod ends.

[0004]

By the way, this conventional strength member has the following problems. That is, since the end of the conventional strength member is composed of a metal part (end fitting), the manufacturing cost for manufacturing this metal part and the mounting processing cost for mounting the CFRP tube are required. However, it had a problem of high cost. In addition, forming the end portion with a metal component (end portion metal fitting) also causes an increase in weight, and thus has another problem that it hinders weight reduction of the strength member itself. In particular, in the aerospace field, it is strongly desired to reduce the weight of parts as much as possible.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a strength member, a truss structure, and a method of manufacturing the strength member, which can achieve cost reduction and weight reduction.

[0006]

The present invention adopts the following means in order to solve the above problems. That is, the strength member according to claim 1 is disposed between the members, and in the strength member that transmits the load between the members, faces the joint body attached to the member and the end portion to which the joint body is fixed. And a fiber-reinforced plastic hollow structure that converges,
The fiber-reinforced plastic hollow structure is characterized in that a threaded portion to which the combined body is screwed is provided at the end portion. According to the strength member of the first aspect, the end portion is made of the same fiber-reinforced composite material as the body, instead of the conventional metal part. Moreover, since the end portion is provided with the screwed portion, the coupling body such as the rod end can be easily attached as in the conventional case. Therefore, since the metal component forming the end portion is not required, the manufacturing cost and the mounting cost of the metal component can be reduced.

According to a second aspect of the present invention, there is provided a strength member according to the first aspect, in which the threaded body forming at least a part of the threaded portion is integrally formed inside the fiber reinforced plastic hollow structure. It is characterized by being provided. According to the strength member of the second aspect, the total length of the screwed portion can be made longer than in the case where there is no screwed body, so the screwed length between the combined body and the fiber structure is large. The length can be secured long enough.

According to a third aspect of the present invention, there is provided the strength member according to the first or second aspect, in which the fiber-reinforced plastic hollow structure is externally attached to the joint body screwed to the end portion. It is characterized in that an abutting member having an abutting surface that is in surface contact with the fiber-reinforced plastic hollow structure and the joint and receives a tensile load, a compressive load, a bending load, or the like acting between them is fixed. . Claim 3
According to this structure, according to the strength member described in (1), even if a relatively large tensile load, compression load, bending load, or the like acts between the fiber-reinforced plastic hollow structure and the bonded body,
All of these are not received by the screwed part but by surface contact by the contact surface, and further, it can be released to the fiber reinforced plastic hollow structure through this contact member, so that the load is not concentrated. Can be dispersed in.

The truss structure according to claim 4 is the structure according to claim 1.
The strength member according to any one of claims 1 to 3 is used. According to the truss structure of the fourth aspect, since the strength member can simultaneously achieve cost reduction and weight reduction, it is possible to configure a low cost and lightweight truss structure.

A method for manufacturing a strength member according to claim 5 is
In a method for manufacturing a strength member that is arranged between members via a connecting member and transmits load between these members, a fiber structure is formed around a mold material so as to converge toward an end to which the connecting member is attached. A base material manufacturing step for manufacturing a fiber structure, a resin impregnation step of impregnating a molten resin into the fiber structure of the fiber structure after the base material manufacturing step to solidify, and the end portion after the resin impregnation step And a mounting step for mounting the coupling member. According to the method for manufacturing a strength member described in claim 5, the end portion of the manufactured strength member can be formed of the same fiber-reinforced composite material as the body instead of the conventional metal part. Therefore,
Since the metal component forming the end portion is not required, the manufacturing cost and the mounting cost of the metal component can be reduced.

The method for manufacturing a strength member according to claim 6 is
The method for manufacturing a strength member according to claim 5, wherein, in the resin impregnating step, the fiber structure is hermetically sealed in a mold in which a recess for accommodating the fiber structure is formed, It is characterized in that the fiber structure is impregnated by injecting a resin. According to the method for manufacturing a strength member described in claim 6, the resin filling the concave portion of the mold is impregnated into the fibrous structure without any gap.

A method for manufacturing a strength member according to claim 7 is
The method for manufacturing a strength member according to claim 6, wherein a hollow member made of a stretchable material such as a thermoplastic resin is used as the mold member, and in the resin impregnating step, an internal pressure is applied to the mold member during the resin injection. Thus, the shape of the fiber structure is maintained. According to the method for manufacturing a strength member according to the seventh aspect, the strength member can be reduced in weight by employing the hollow member as the mold material that becomes a part of the strength member after manufacturing. Moreover, since this mold material is kept under internal pressure during resin injection, its shape can be properly maintained even when external pressure (compression) is applied by the injected resin, and the fiber structure is given a shape. The function as a mold for working can be fully exerted.

The method for manufacturing a strength member according to claim 8 is
The method for manufacturing a strength member according to claim 7, wherein the internal pressure of the mold member is applied through a through hole to which the coupling member is attached. According to the method of manufacturing a strength member described in claim 8, it is not necessary to form a dedicated hole in the strength member wall surface only for performing internal pressurization.

The method for manufacturing a strength member according to claim 9 is
The method for manufacturing a strength member according to any one of claims 5 to 8, wherein in the base material manufacturing step, a coupled member that is coupled to the coupling member is attached to an end portion of the mold material to be integrated. In addition, the fiber structure is formed around these mold members and members to be bonded. According to the method for manufacturing a strength member described in claim 9, the member to be coupled can be integrally fixed in the strength member after the formation of the fibrous structure. As a result, the attachment strength of the combined body can be increased as compared with the case where there is no member to be connected.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The strength member of the present invention is arranged, for example, between members to perform load transmission between these members, and one embodiment thereof will be described below with reference to the drawings. Of course, the present invention is not limited to this. Note that FIG. 1 is a view showing the strength member of the present embodiment, and is a cross-sectional view when seen in a cross-section including the axis thereof. Further, FIG. 2 is a partially enlarged view showing an end portion of the same strength member.

As shown in FIG. 1, the strength member of this embodiment is a rod end 1 which is a pair (two) of eyebolts.
It is roughly configured by including a (combined body) and a tubular fiber-reinforced plastic hollow structure 2 having both ends 2a that converge toward a fixed portion to which these rod ends 1 are fixed. In the figure, for the sake of explanation, the state where each rod end 1 is removed from the fiber reinforced plastic hollow structure 2 is shown, but in reality, as shown in FIG. In contrast, each rod end 1 is attached and used as one component.

Each rod end 1 is, for example, a metal component such as aluminum, and as shown in FIG. 1, a connecting portion 1a connected to a rod end (not shown) of the member or another strength member, and A male screw portion 1b screwed to the end portion 2a is provided. The rod end 1 is not limited to metal, and a resin material may be used as the material.

The fiber reinforced plastic hollow structure 2 is mainly composed of a CFRP (fiber reinforced plastic) tube, and has a long hollow cylindrical shape squeezed at both ends 2a as shown in FIG. This fiber-reinforced plastic hollow structure 2 is a hollow cylindrical liner 4 (mold material) whose both ends are squeezed and which is made of a stretchable material such as a thermoplastic resin.
A structure in which the reinforcing fibers 3 are tightly wound around the periphery of the resin using a technique such as braiding or filament winding is created, and the reinforcing fibers 3 are impregnated with the molten resin and further cured. The resin impregnation / curing will be described later.

As shown in FIG. 2, each of the rod ends 1 is attached to both ends 2a of the fiber reinforced plastic hollow structure 2.
The female screw portion 2b (screw portion) to which the male screw portion 1b is screwed is formed. These internal threaded portions 2b are screwed members 5 integrally fixed to the inside of the fiber-reinforced plastic hollow structure 2.
(Screw body, member to be coupled), contact member 6 integrally fixed to the outside of the fiber-reinforced plastic hollow structure 2, and both end portions 2a sandwiched between the screw body 5 and the contact member 6.
Is a female screw hole that simultaneously penetrates the wall of the.

Each screw body 5 is made of a metal part such as an aluminum material, and has a general shape obtained by dividing a hollow sphere in half. These screwed bodies 5 are closely fixed to the outer wall surfaces of the fiber reinforced plastic hollow structure 2 at both outer ends on the spherical surface formed inside thereof. In addition, each screw 5
As the material, not only metal but also resin material may be adopted as the material. Each contact member 6 is made of, for example, a metal component such as an aluminum material, and has an inner wall surface that is in close contact with each end 2a of the fiber-reinforced plastic hollow structure 2. Then, these abutting members 6 are adhesively fixed to the outer wall surface of each end 2a on the inner wall surface thereof. Further, the outer wall surfaces of these abutting members 6 are in surface contact with the nut portion 1c of the rod end 1 that is screwed, and these rod end 1
Also, contact surfaces 6a that receive a tensile load, a compressive load, a bending load, or the like acting between the fiber-reinforced plastic hollow structures 2 are formed. Note that each contact member 6 is not limited to metal, and a resin material may be used as the material.

The strength member having the above-described structure is lightweight, but can exhibit extremely high strength against a compressive load, a tensile load, and a bending load. Therefore, a plurality of such strength members should be combined with each other. Thus, it is possible to construct a truss structure that is light and has excellent strength and is low in cost. Suitable applications of this truss structure are, for example, transportation structures in the aerospace field, building structures, etc., but are not limited to this, and are applicable to a wide range of other applications.

Next, one embodiment of the method for manufacturing the strength member of this embodiment will be described below with reference to FIGS. 3 and 4. 3 is a view for explaining the method for manufacturing the same strength member, and is a cross-sectional view showing the strength member inserted into the mold. Further, FIG. 4 is a partially enlarged view showing an end portion of the same strength member in the mold. FIG. 5 is a view showing a modified example of the same strength member, and is a partially enlarged cross-sectional view of the end portion.

The manufacturing method of this embodiment is manufactured through a base material manufacturing step, a resin impregnating step, a contact member attaching step, and a rod end attaching step, which will be described below.
That is, although not shown in the drawing, in the base material manufacturing process, braiding is performed so that the reinforcing fibers 3 are converged around both ends 2a around the liner 4 in which each screw 5 is fixed to the outside in advance. A fiber structure is manufactured by forming a fiber structure using a method such as a filament winding method. At this point, the reinforcing fibers 3 have not yet been impregnated with the resin.

In the subsequent resin impregnation step, first, the fiber structure (reinforcing fiber 3) of the fiber structure after the base material manufacturing step.
Is impregnated with the molten resin. That is, as shown in FIG. 3, after sealing the fiber structure in a female mold 10 (mold) in which a recess 10a for accommodating the fiber structure is formed, the resin L is placed in the recess 10a. The fibrous tissue is impregnated by injection.

This female mold 10 is provided with a resin injection port 10b.
Is connected to the storage tank 11 for the resin L via
Resin can be injected into the recess 10a from the storage tank 11. Further, the female die 10 is connected to a vacuum pump (not shown) via an exhaust port 10c communicating with the inside of the recess 10a. Therefore, by vacuuming the inside of the recess 10a with this vacuum pump and at the same time injecting the resin L, the resin L is filled without generating bubbles between the inner wall surface of the recess 10a and the outer peripheral surface of the liner 4. It is supposed to be done. As a result, the reinforcing fiber 3 is impregnated with the resin L without any gap.

The liner 4 during resin injection in the resin impregnation step receives a compressive load from the surroundings by the resin L filled in the recess 10a.
However, since it is kept at a constant internal pressure by compressed air A from a pressurizing pump (not shown), its shape can be appropriately maintained without being dented, and the function as a male mold for imparting a shape to the fibrous tissue. It is designed to be able to fully demonstrate. Internal pressurization of the liner 4 at this time is performed by using a through hole at an end to which the rod end 1 is attached. As a result, it is not necessary to form a dedicated hole on the wall surface of the strength member only for performing internal pressurization.

As shown in FIG. 4, the end portion having the through hole for pressurizing is exposed to the outside of the female die 10, but is provided inside the female die 10. Since it is sealed by the ring 12, the resin L does not leak to the outside from here. When the resin L comes out of the female die 10 through the exhaust port 10c, it is determined that the resin injection into the recess 10a is completed, and therefore the resin injection is stopped. After heating the female die 10 for a predetermined time, the heating is stopped and the female die 10 is cooled to room temperature. Then, the resin L impregnated in the reinforcing fiber 3 is cured, so that the female mold 1
Open 0, take out the contents, and cut off the protruding parts at both ends for internal pressurization.

In the subsequent contact member attaching step, each contact member 6 is attached to both ends 2a of the fiber reinforced plastic hollow structure 2.
Adhesively fixed to each. Then, each female screw portion 2b
By cutting the female screw of, the state shown in FIG. 1 is obtained, and the fiber-reinforced plastic hollow structure 2 is completed. In the subsequent rod end attaching step (attaching step), the rod ends 1 are completely screwed to both ends 2a after the resin impregnation step, whereby the fixed state shown in FIG. 2 is obtained, and the strength member is completed.

The strength member of the present embodiment described above includes each rod end 1 and the fiber reinforced plastic hollow structure 2 that converges toward both ends 2a, and both end parts of the fiber reinforced plastic hollow structure 2 are provided. The structure in which the female screw portion 2b is formed on 2a is adopted. Further, in the manufacturing method, a method of manufacturing through a base material manufacturing step, a resin impregnation step, a contact member attaching step, and a rod end attaching step is adopted. According to the structure and the manufacturing method of the strength member, both ends 2a of the strength member are made of the same fiber reinforced composite material as the body, and a separate and heavy metal part is not required, so that the cost is low. It is possible to achieve both weight reduction and weight reduction at the same time.

Further, the strength member of the present embodiment employs a structure in which the respective threaded members 5 are integrally provided inside the fiber reinforced plastic hollow structure 2. According to this configuration, the length of the threaded portion between each rod end 1 and the fibrous structure 2 can be ensured to be sufficiently long, so that the fixing strength of each rod end 1 to the fibrous structure 2 is strengthened. Is possible.

In the strength member of this embodiment, an abutting member having an abutting surface 6a for receiving a tensile load, a compressive load, a bending load or the like is adhered to the outside of both ends 2a of the fiber reinforced plastic hollow structure 2. The fixed structure is adopted. According to this configuration, the load can be dispersed so as not to be concentrated by uniformly escaping the load to the fiber-reinforced plastic hollow structure 2 through the contact member 6, and thus the mechanical strength is further improved. It is possible, and it is possible to secure high reliability as a strength member.

Further, in the method for manufacturing a strength member of this embodiment, the fiber structure is made into the female mold 10 in the resin impregnation step.
After sealing the inside, a method of impregnating the fiber structure by injecting the resin L while drawing a vacuum was adopted. According to this method, the resin L is surely impregnated into the fibrous structure without any gaps, so that it is possible to reliably manufacture a defect-free strength member.

In the above embodiment, the rod ends 1 are directly screwed to the female screw portions 2b formed at both ends 2a of the fiber reinforced plastic hollow structure 2, but the present invention is not limited to this. For example, as shown in FIG.
It is also possible to adopt a configuration in which the bolts 13 in which the female screw holes 13a are formed coaxially are screwed to both ends 2a of the fiber reinforced plastic hollow structure 2, and the rod ends 1 are screwed and attached to the female screw holes 13a.

[0034]

The strength member according to claim 1 of the present invention is
A structure is provided in which a combined body and a fiber-reinforced plastic hollow structure that converges toward the end are provided, and a screw portion is provided at the end of the fiber-reinforced plastic hollow structure. According to this configuration, since the end portion of the strength member is made of the same fiber reinforced composite material as the body, there is no need for a separate and heavy metal part, so that cost reduction and weight reduction can be achieved at the same time. It becomes possible to do.

The strength member according to a second aspect of the invention is the strength member according to the first aspect of the invention, in which the threaded body is integrally provided inside the fiber-reinforced plastic hollow structure. According to this configuration, the screwing length between the combined body and the fiber structure can be sufficiently long, so that the fixing strength of the combined body with respect to the fiber structure can be strengthened.

The strength member according to a third aspect is the strength member according to the first or second aspect, in which a tensile load, a compressive load, a bending load, or the like is applied to the outside of the fiber-reinforced plastic hollow structure. A structure for fixing an abutting member having an abutting surface for receiving is adopted. According to this configuration, by releasing the load to the fiber-reinforced plastic hollow structure via the contact member, it is possible to disperse the load so as not to concentrate, it is possible to further improve the mechanical strength, It becomes possible to secure high reliability as a strength member.

Further, the truss structure described in claim 4 adopts a structure using the strength member described in any one of claims 1 to 3. According to this configuration, the strength member can simultaneously achieve cost reduction and weight reduction, so that it is possible to configure a low cost and lightweight truss structure.

In the method for manufacturing a strength member according to a fifth aspect of the present invention, there is provided a base material manufacturing step of manufacturing a fiber structure by forming a fiber structure around the mold material so that the fiber structure is converged toward the ends thereof. A method having a resin impregnation step of impregnating the tissue with molten resin to solidify it and an attaching step of attaching a coupling member was adopted. According to this method, the end portion of the manufactured strength member is made of the same fiber reinforced composite material as the body, and since a separate and heavy metal part is not required, cost reduction and weight reduction can be achieved. Can be achieved at the same time.

The method for manufacturing a strength member according to claim 6 is the same as the method for manufacturing a strength member according to claim 5,
In the resin impregnation step, after the fiber structure was sealed in a mold, a resin was injected to impregnate the fiber structure. According to this method, the resin is surely impregnated into the fibrous structure without any gaps, so that it is possible to reliably manufacture a defect-free strength member.

The method for manufacturing a strength member according to claim 7 is the same as the method for manufacturing a strength member according to claim 6,
Using a hollow member as the mold material, in the resin impregnation step,
A method of retaining the shape of the fiber structure by applying internal pressure to the mold material during resin injection was adopted. According to this method, it is possible to reduce the weight of the reinforcing member by using the hollow mold member. Further, although this mold material is hollow, it is possible to secure the strength as a mold by receiving internal pressure during resin injection, so that it is possible to improve the product yield.

The method of manufacturing a strength member according to claim 8 is the same as the method of manufacturing a strength member according to claim 7,
A method of applying internal pressure to the mold through a through hole to which a coupling member is attached is adopted. According to this method, it is not necessary to form a hole in the wall of the strength member only for performing internal pressurization, so that no extra hole is left in the strength member after manufacturing. Therefore, it is possible to prevent the strength of the strength member from decreasing.

A method for manufacturing a strength member according to a ninth aspect is the method for manufacturing a strength member according to any one of the fifth to eighth aspects, in which the base material manufacturing step is performed to produce the mold material. After attaching the member to be joined to the end to make it integral,
The method of forming fibrous tissue was adopted. According to this method, as compared with the case where there is no member to be bonded, it becomes possible to strengthen the fixing strength of the bonded body to the fiber structure.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of a strength member of the present invention and is a cross-sectional view when seen in a cross section including an axis thereof.

FIG. 2 is a partially enlarged view showing an end portion of the same strength member.

FIG. 3 is a view for explaining the method of manufacturing the same strength member, and is a cross-sectional view showing the strength member inserted into the mold.

FIG. 4 is a partial enlarged view showing an end portion of the same strength member in the mold.

FIG. 5 is a diagram showing a modified example of the same strength member, and is a partially enlarged cross-sectional view of an end portion.

[Explanation of symbols]

1 ... Rod end (combined body) 2 ... Fiber reinforced plastic hollow structure 2a ... end 2b: Female screw hole (threaded portion) 3 ... Reinforcing fiber (fiber structure) 4 ... Liner (mold material) 5 ... Threaded body (threaded body, member to be coupled) 6 ... Contact member 6a ... Abutting surface 10 ... Female mold (mold) 10a ... recess L: Resin

Continued front page    (72) Inventor Shoichiro Asada             Mitsubishi Heavy, 10 Oemachi, Minato-ku, Nagoya-shi, Aichi             Industrial Co., Ltd. Nagoya Aerospace System Production             In-house (72) Inventor Yoshiyuki Nakagome             Mitsubishi Heavy, 10 Oemachi, Minato-ku, Nagoya-shi, Aichi             Industrial Co., Ltd. Nagoya Aerospace System Production             In-house (72) Inventor Masahiro Shinya             Mitsubishi Heavy, 10 Oemachi, Minato-ku, Nagoya-shi, Aichi             Industrial Co., Ltd. Nagoya Aerospace System Production             In-house F term (reference) 2E163 DA02 DA04 FE03 FF73                 4F205 AB11 AD16 AG07 AG21 AH47                       AM28 HA06 HA25 HA35 HA47                       HB01 HC07 HF30 HK17 HK32                       HM06 HW02 HW21

Claims (9)

[Claims] 1. A strength member arranged between members for transmitting a load between the members, wherein a joined body attached to the member and a fiber reinforced plastic hollow converging toward an end to which the joined body is fixed. And a structure, wherein the end portion of the fiber-reinforced plastic hollow structure is provided with a screwing portion to which the coupling body is screwed. 2. The strength member according to claim 1, wherein the fiber-reinforced plastic hollow structure is integrally provided with a threaded body that forms at least a part of the threaded portion. And strength members. 3. The strength member according to claim 1 or 2, wherein the fiber-reinforced plastic hollow structure is in surface contact with the outside of the fiber-reinforced plastic hollow structure, and the combined structure is screwed to the end. A strength member, characterized in that an abutting member having an abutting surface that receives a tensile load, a compressive load, a bending load, or the like acting between the fiber-reinforced plastic hollow structure and the bonded body is fixed. 4. A truss structure, wherein the strength member according to any one of claims 1 to 3 is used. 5. A method of manufacturing a strength member, which is arranged between members via a connecting member and transmits a load between these members, wherein the fiber is converged around a mold member toward an end to which the connecting member is attached. A base material manufacturing step of forming a structure to manufacture a fiber structure; a resin impregnation step of impregnating a molten resin into the fiber structure of the fiber structure after the base material manufacturing step to solidify the resin; and the resin impregnating step. And a step of attaching the coupling member to the end portion afterward. 6. The method for manufacturing a strength member according to claim 5, wherein, in the resin impregnating step, after sealing the fiber structure in a mold in which a recess for accommodating the fiber structure is formed,
A method for manufacturing a strength member, characterized in that the fiber structure is impregnated by injecting the resin into the recess. 7. The method for manufacturing a strength member according to claim 6, wherein a hollow member made of a stretchable material such as a thermoplastic resin is used as the mold member, and the mold member during the resin injection is used in the resin impregnation step. A method for manufacturing a strength member, characterized in that the shape of the fiber structure is maintained by applying internal pressure to the. 8. The method of manufacturing a strength member according to claim 7, wherein the internal pressure of the mold member is applied through a through hole to which the coupling member is attached. 9. The method for manufacturing a strength member according to claim 5, wherein in the base material manufacturing step, a joined member that joins the joining member to an end portion of the mold member. After attaching and integrating
A method for manufacturing a strength member, characterized in that the fibrous structure is formed around these mold members and members to be bonded.