JP2020175626A - Fiber-reinforced plastic body and connection members - Google Patents

Abstract

To provide a fiber-reinforced plastic body having a perforated portion and a connecting member using the same, which prevents the fiber layer in the periphery of the perforated portion from failing, even under a stress that is expanded due to a stress concentration occurring in the periphery of the perforated portion when a load is inputted, and a connecting member using the same.SOLUTION: A connecting member 10 comprises a fiber-reinforced resin body having a plurality of fiber bundles and a resin 15 impregnated between the plurality of fiber bundles and the like. The connecting member has a perforated portion 11. The periphery of the perforated portion 11 has: a first portion 16 including fiber bundles oriented in a direction that is approximately orthogonal to a central axis O1 of the perforated portion 11; and a second portion 17 including fiber bundles oriented in a direction along a central axis O1 of the perforated portion 11.SELECTED DRAWING: Figure 2B

Description

The present invention relates to, for example, a fiber-reinforced resin body used as a structural member incorporated in a vehicle or the like, and a connecting member having the fiber-reinforced resin body and connecting the members to each other.

Fiber reinforced plastics (FRP) have been used as structural members constituting vehicles and the like because they satisfy the requirements of excellent mechanical properties and weight reduction. When a fiber-reinforced resin body made of such a fiber-reinforced resin (fiber-reinforced resin structure) is attached to another member as a structural member, mechanical fastening means (connecting member, mechanical) such as a bolt is attached to the fiber-reinforced resin body. It is necessary to provide a hole for inserting the connecting element).

For example, Patent Document 1 includes a main body portion molded using a fiber reinforced resin and a hole portion provided in the main body portion, and continuous fibers are arranged along the periphery of the hole portion. Reinforced resin bodies are described.

Japanese Unexamined Patent Publication No. 2017-132083

The fiber-reinforced resin body described in Patent Document 1 has a fiber layer containing fiber bundles oriented in one direction, and continuous fibers oriented around the central axis of the pores are reinforced between the fiber layers. Arranged as layers.

Here, in the fiber-reinforced resin body having holes, when a load (force) is input to the fiber-reinforced resin body, stress is concentrated on the outer peripheral portion of the holes. In this regard, according to the fiber-reinforced resin body described in Patent Document 1, since the continuous fibers are arranged along the periphery of the pores, the strength of the pores is increased.

However, since the continuous fibers are oriented around the central axis of the hole, the reinforcing layer is fractured so as to sew a gap between the fibers along a direction orthogonal to the central axis of the hole. (Transverse crack) is likely to occur. Further, since both the continuous fibers of the reinforcing layer and the fiber bundles of the fiber layer are oriented in the direction orthogonal to the central axis of the hole, when a crack occurs in the reinforcing layer, the crack is the reinforcement. It propagates from one layer to another fiber layer, progresses to the entire fiber-reinforced resin body in a chain of delamination and breakage of fiber bundles in the fiber layer, and the fiber-reinforced resin body is destroyed.

The present invention has been made in view of such a problem, and in a fiber reinforced resin body having a hole and a connecting member using the same, stress generated in the outer peripheral portion of the hole when a load is input. It is an object of the present invention to provide a fiber reinforced resin body and a connecting member capable of preventing damage to the fiber layer existing in the outer peripheral portion even under stress expanded by concentration.

A brief outline of the typical inventions disclosed in the present application is as follows.

[1] The fiber-reinforced resin body has a plurality of fiber bundles and a resin impregnated between the plurality of fiber bundles. The fiber-reinforced resin body has a hole portion, and the outer peripheral portion of the hole portion includes a first portion including a fiber bundle oriented in a direction substantially orthogonal to the drawing axis of the hole portion, and a stretch of the hole portion. It has a second portion containing a bundle of fibers oriented along the axis.

[2] In the fiber-reinforced resin body according to [1], the first portion is arranged at the center of the hole in the direction along the drawing axis of the hole, and is outside the first portion. The second part is arranged.

[3] In the fiber-reinforced resin body according to [2], the first portion is further arranged outside the second portion in a direction along the stretching axis of the hole.

[4] In the fibrous resin body according to [1], the second portion is arranged at the center of the hole in the direction along the stretching axis of the hole, and the second portion is arranged at the end of the hole. Part 1 is arranged.

[5] In the fiber-reinforced resin body according to any one of [1] to [4], the first portion and the second portion are at least at least in the direction along the drawing axis of the pore portion. It occupies 25% or more of the total length of the hole.

[6] In the fiber-reinforced resin body according to any one of [1] to [5], the fiber content of the second portion is 40 to 70% by volume.

[7] In the fiber-reinforced resin body according to any one of [1] to [6], the outer peripheral portion of the hole portion further has a foaming material.

[8] In the fiber-reinforced resin body according to [7], a part of the fiber bundle constituting the first portion is replaced with the foaming material.

[9] In the fiber-reinforced resin body according to any one of [1] to [8], the outer peripheral portion of the hole portion is a fiber contained in the first portion and the second portion, respectively. It has a third portion containing a fiber bundle oriented in a direction different from that of the bundle, and the third portion is arranged on the outer periphery of the second portion in the circumferential direction of the drawing axis of the hole portion. There is.

[10] In the fiber-reinforced resin body according to [9], the third portion is composed of a plurality of laminated fiber layers, and the laminated structure of the third portion is a pseudo isotropic laminated structure.

[11] In the fiber-reinforced resin body according to any one of [1] to [10], the first portion is composed of a plurality of laminated fiber layers, and the laminated structure of the first portion is , Pseudo isotropic laminated structure.

[12] In the connecting member having the fiber-reinforced resin body according to any one of [1] to [11], the two insertion portions having the holes and the connecting portion connecting the two insertion portions to each other. And have.

[13] In the connecting member according to [12], the connecting portion includes a fiber bundle oriented in the direction of a line segment connecting the centers of the holes of the two insertion portions.

[14] In the connecting member according to [12] or [13], the first portion is a fiber bundle oriented in the direction of a line segment connecting the centers of the holes of the two insertion portions. Including.

According to the present invention, in a fiber reinforced resin body having a hole and a connecting member using the same, even under stress expanded due to stress concentration generated on the outer periphery of the hole when a load is input. It is possible to provide a fiber reinforced resin body and a connecting member capable of preventing damage to the fiber layer existing in the outer peripheral portion.

It is a perspective view which shows the connecting member which concerns on 1st Embodiment. It is a side view which shows the connecting member which concerns on 1st Embodiment. It is a top view which shows the connecting member which concerns on 1st Embodiment. It is a cross-sectional view of a main part which shows the structure cut along the AA' line of FIG. 1B. FIG. 2 is an enlarged view of a main part of the D portion of FIG. 2A, which also serves as an enlarged view of the main part of the D portion of the shaped body after the combination step. It is sectional drawing of the main part which shows the structure cut along the line BB'of FIG. 1A. It is an enlarged view of the main part of the F part of FIG. 3A. It is a flow which shows the manufacturing process of the connecting member which concerns on 1st Embodiment. It is a perspective view which shows each member which comprises the connecting member in the combination process in the manufacturing process of the connecting member which concerns on 1st Embodiment. It is sectional drawing of the main part which shows the structure which cut at the position corresponding to the line AA'in FIG. 1B in the connecting member which concerns on 1st modification of 1st Embodiment. FIG. 5 is a cross-sectional view of a main part showing a structure cut at a position corresponding to the line AA'in FIG. 1B in the connecting member according to the second modification of the first embodiment. It is sectional drawing of the main part which shows the structure which cut at the position corresponding to the line AA'in FIG. 1B in the connecting member which concerns on the 3rd modification of 1st Embodiment. It is sectional drawing which shows the test piece of the Example which concerns on this invention. It is sectional drawing which shows the test piece of the comparative example 1. FIG. It is sectional drawing which shows the test piece of the comparative example 2. FIG. It is a schematic diagram explaining the test method of the test piece shown in FIG. It is a graph which shows the test result of an Example and a comparative example.

(First Embodiment)
Hereinafter, the fiber-reinforced resin body of the first embodiment (hereinafter, may be referred to as the first aspect), which is a preferred embodiment of the present invention, will be described with reference to the drawings. In each figure showing the embodiment and the modified example, the same or similar parts or components are indicated by the same or similar symbols or reference numbers, and the description is not repeated in principle.

<Structure of fiber-reinforced resin body of the first aspect and its action and effect>
Hereinafter, the configuration of the fiber-reinforced resin body of the first aspect will be described. The fiber-reinforced resin body according to the first aspect is a form applied as a connecting member as a preferable application example thereof. Therefore, as a first aspect, a connecting member to which a fiber-reinforced resin body is applied will be described below as an example. 1A is a perspective view showing the connecting member 10 according to the first aspect, FIG. 1B is a side view of the connecting member 10 of FIG. 1A, and FIG. 1C is a plan view of the connecting member 10 of FIG. 1A. FIG. 2A is a cross-sectional view of a main part showing a structure cut along the line AA'of FIG. 1B, and FIG. 2B is an enlarged view of a main part of the D portion of FIG. 2A. FIG. 3A is a cross-sectional view of a main part showing a structure cut along the line BB'of FIG. 1B, and FIG. 3B is an enlarged view of a main part of the F portion of FIG. 3A. Note that FIG. 2B also serves as an enlarged view of a main part of the D portion of the shaped body after the combination step.

First, the characteristic configuration of the connecting member (fiber reinforced resin body) 10 according to the first aspect will be described. As shown in FIGS. 2B and 3B, the fiber-reinforced resin body 10 according to the first aspect is impregnated between the fiber layers 14a to 14i including a plurality of fiber bundles and the fiber bundles contained in the plurality of fiber layers 14a to 14i. It has the resin 15. The fiber bundles contained in the plurality of fiber layers 14a to 14i are oriented (aligned) in a predetermined direction (orientation angle), respectively. Then, as shown in FIGS. 1A and 1B, the fiber-reinforced resin body 10 of the first aspect has two pores 11.

Here, the axis along the direction in which the hole 11 extends is defined as the extension axis. In the fiber-reinforced resin body 10 according to the first aspect, since the cross-sectional shape of the hole portion 11 is circular, the extension axis of the hole portion 11 is an axis passing through the centers O1 and O2 of the hole portion 11 (hereinafter, the central axis O1, It may be called O2.) Therefore, in the following, the extension shaft of the hole 11 will be described as the central axes O1 and O2 of the hole 11 (the "central axis" below can be appropriately read as the "extension shaft". The same applies to the modified example). .. Further, the configurations around the right and left hole portions 11 shown in FIG. 1B are basically the same, and the center O1 (central axis O1) of the left hole portion 11 and the center O2 (central axis O2) of the right hole portion 11 ) Is merely a distinction for convenience. Therefore, the configuration around the center O1 (central axis O1) of the hole portion 11 on the left side will be described below as an example, and the description of the configuration around the hole portion 11 on the right side will be omitted.

As shown in FIG. 2B, in the fiber reinforced resin body 10 according to the first aspect, the outer peripheral portion of the hole portion 11 is a fiber layer 14a including a fiber bundle oriented in a direction substantially orthogonal to the central axis O1 of the hole portion 11. , 14b, 14c, 14d (hereinafter, these fiber layers may be referred to as axially orthogonal fiber layers 14a and the like), and the first portion 16 is oriented in the direction along the central axis O1 of the hole portion 11. It has a second portion 17 composed of a fiber layer 14e (hereinafter, this fiber layer may be referred to as an axially parallel fiber layer 14e) including a fiber bundle. The fiber-reinforced resin body 10 of the first aspect shown in FIG. 2B includes a third portion 19 described below as a preferable configuration, but the third portion 19 is not necessarily an essential configuration in the present invention. Instead, it may be arranged as needed.

In the first aspect, by adopting the above configuration, the stress concentration generated in the outer peripheral portion of the hole portion 11 when a load is input in the connecting member (fiber reinforced resin body) 10 having the hole portion 11. It is possible to prevent the fiber layers 14a to 14e existing on the outer peripheral portion from being damaged even under the stress expanded by the above. The reason will be specifically described below.

As described above, when a load is input to the connecting member having the hole, the stress is concentrated on the outer peripheral portion of the hole. When the fiber layer constituting the connecting member includes a fiber bundle oriented in a direction orthogonal to the central axis of the hole, transverse cracks are likely to occur. Further, when the orientation directions of the fiber bundles contained in the fiber layer are all the same, when a crack occurs in the fiber layer due to a transverse crack, the crack propagates from the fiber layer to another fiber layer, and delamination in the fiber layer occurs. And the breakage of the fiber bundle proceeds to the entire connecting member in a chain, and the connecting member may break.

On the other hand, as a characteristic configuration of the connecting member (fiber reinforced resin body) 10 of the first aspect, as shown in FIG. 2B, the outer peripheral portion of the hole portion 11 is substantially connected to the central axis O1 of the hole portion 11. An axially parallel fiber layer including a first portion 16 composed of an axially orthogonal fiber layer 14a and the like including fiber bundles oriented in orthogonal directions and a fiber bundle oriented in a direction along the central axis O1 of the hole portion 11. It has a second portion 17 composed of 14e.

Since the connecting member 10 of the first aspect has the characteristic structure as described above, when a load is input to the hole portion 11, the connecting member 10 of the first aspect is assumed to be formed on the axially orthogonal fiber layer 14a or the like in the first portion 16. Even when cracks occur, a second fiber bundle composed of a fiber bundle included in the axially orthogonal fiber layer 14a and the like and an axially parallel fiber layer 14e including fiber bundles having different orientation directions with respect to the central axis O1 of the hole portion 11. Since the portion 17 is provided, the crack is less likely to propagate from the first portion 16 to the second portion 17. As a result, it is possible to prevent delamination and breakage of fiber bundles in the fiber layers 14a to 14e.

In particular, since the second portion 17 is composed of an axially parallel fiber layer 14e including a fiber bundle oriented in a direction along the central axis O1 of the hole portion 11, the yz (definition of the axis will be described later) plane. It is possible to increase the strength against shear stress acting inward.

Further, since the first portion 16 is composed of an axis orthogonal fiber layer 14a or the like including a fiber bundle oriented in a direction substantially orthogonal to the central axis O1 of the hole portion 11, the out-of-plane direction which is the z-axis direction. It is possible to increase the strength against the stress (punching shear stress) generated by the punching force acting from.

Further, the fiber-reinforced resin body 10 of the first aspect includes both the first portion 16 including the axially orthogonal fiber layer 14a and the like and the second portion 17 including the axially parallel fiber layer 14e. Even when a complex stress from multiple directions acts on the outer peripheral portion of the hole portion 11, the stress is applied to both the axially orthogonal fiber layer 14a and the fiber bundle included in each of the axially parallel fiber layers 14e. By bearing the stress, it is possible to achieve a combined effect that the effect of suppressing breakage of the fiber layers 14a to 14e is enhanced in the outer peripheral portion of the hole portion 11.

From the above, in the first aspect, in the fiber reinforced resin body 10 having the hole portion 11, when a load is input, the outer circumference thereof is expanded even under the stress concentration caused by the stress concentration generated in the outer peripheral portion of the hole portion 11. It is possible to prevent the fiber layer existing in the portion from being damaged.

<Structure of connecting member of the first aspect>
Hereinafter, the configuration of the connecting member of the first aspect will be described. The following "connecting member" can be appropriately read as "fiber reinforced resin body" (the same applies to the modified examples described below).

As shown in FIGS. 1A to 1C, the connecting member 10 according to the first aspect has two insertion portions 12 having holes 11 and connecting portions 13 connecting the two insertion portions 12 to each other. .. Although not particularly limited, the connecting member 10 according to the first aspect, which is a preferred embodiment, is configured as, for example, an upper arm (upper link) for a vehicle. Therefore, the two insertion portions 12 are formed in a substantially cylindrical shape, for example, and are configured so that a shaft member such as a shaft can be inserted into each hole portion 11.

Here, as shown in FIGS. 1A to 1C, the direction along the central axis O1 of the hole portion 11 is the z-axis direction (direction perpendicular to the paper surface in FIG. 1B) and the respective hole portions of the two insertion portions 12. The direction along the line connecting the centers O1 and O2 of 11 and orthogonal to the z-axis is the x-axis direction (horizontal to the paper surface in FIG. 1B) and the direction orthogonal to both the x-axis and the z-axis. Is defined as the y-axis direction (vertical direction with respect to the paper surface in FIG. 1B) (hereinafter, the same applies to all the figures). Therefore, all the arbitrary directions included in the xy plane are directions substantially orthogonal to the central axis O1 of the hole portion 11.

The connecting member 10 of the first aspect is a fiber reinforced resin body in which the insertion portion 12 and the connecting portion 13 are all made of a fiber reinforced resin, and as shown in FIGS. 2B and 3B, the connecting member 10 constitutes the connecting member 10. The insertion portion 12 and the connecting portion 13 are composed of a fiber-reinforced resin body having a plurality of fiber layers 14a to 14i including fiber bundles and a resin 15 impregnated between the fiber bundles included in each fiber layer 14a to 14i. There is. Specifically, as shown in FIGS. 1A to 1C, 2A, and 3A, the connecting member 10 of the first aspect has L-shaped parts 60a and 60b, back parts 70, and rings 80, each of which is made of fiber reinforced resin. It is formed by combining each member of. Then, as shown in FIG. 3A, the connecting portion 13 having a substantially T-shaped cross section along the yz plane has a substantially rectangular upper side portion 55 extending in the z-axis direction and a central portion of the upper side portion 55 extending in the y-axis direction. It has a pillar portion 56 connected to the above. In the upper side portion 55, the back part 70 and the bent piece portions 65a and 65b of the L-shaped parts 60a and 60b are integrated, so that the pillar portion 56 has two connecting piece portions 63 of the L-shaped parts 60a and 60b. Each is configured by being integrated. Further, as shown in FIGS. 1A to 1C, 2A and 3A, in the x-axis direction, the back part 70 constituting the connecting portion 13 and the connecting piece portion 63 of the L-shaped parts 60a and 60b have a substantially circular tube shape. The insertion portion 12 is configured by integrally incorporating the ring 80 into both ends of the molded portion. As described above, the insertion portion 12 and the connecting portion 13 are integrally formed to form the connecting member 10.

As described above, the laminated structure of the outer peripheral portion of the hole portion 11 in the first aspect shown in FIG. 2B includes the connecting member 10, that is, the hole portion 11, which is a structural member constituting the vehicle or the like shown in FIGS. 1A to 1C. It is suitable for application to a connecting member 10 having two inserting portions 12 and a connecting portion 13 for connecting the two inserting portions 12 to each other. That is, in the connecting member 10 of the first aspect, when a load is input through the hole portion 11, the outer circumference is increased by stress concentration generated in the outer peripheral portion of the hole portion 11. It is possible to prevent the fiber layer existing in the portion from being damaged.

Hereinafter, the detailed structure of the connecting member 10 according to the first aspect will be described separately for the inserting portion 12 and the connecting portion 13.

<Insert>
First, the configuration of the insertion portion 12 of the connecting member 10 according to the first aspect, that is, the configuration of the outer peripheral portion of the hole portion 11 will be described. As shown in FIGS. 2B and 3B, since the connecting member 10 of the first aspect is configured to be line-symmetrical with respect to the center line C in the z-axis direction, the left side of the center line C in the z-axis direction. The components existing on the right side (for example, L-shaped parts 60a, etc.) will be described in detail, and the components existing on the right side (for example, L-shaped parts 60b, etc.) will be omitted as appropriate (described below. The same applies to other embodiments).

As shown in FIG. 2B, in the connecting member 10 according to the first aspect, the first portion 16 formed of the axially orthogonal fiber layer 14a and the like constituting the insertion portion 12 is along the central axis O1 of the hole portion 11. In the direction (z-axis direction), a second portion 17 composed of an axially parallel fiber layer 14e is arranged outside the first portion 16 and is arranged in the central portion M1 of the hole portion 11. In particular, in the insertion portion 12 according to the first aspect, the second portion 17 is arranged at the end portion E1 of the hole portion 11 in the z-axis direction. Thereby, in the z-axis direction, the strength against the shear stress acting in the yz plane in the vicinity of the end portion E1 of the hole portion 11 can be increased.

Further, in the insertion portion 12 according to the first aspect, the first portion 16 is composed of two laminated portions 18a and 18b in which a plurality of fiber layers are laminated. The stacking direction of the fiber layers constituting the laminated portions 18a and 18b coincides with the direction (z-axis direction) along the central axis O1 of the hole portion 11. Further, in the insertion portion 12 of the first aspect, the second portion 17 is composed of a laminated portion 18c in which a plurality of fiber layers are laminated. The stacking direction of the fiber layers constituting the laminated portion 18c coincides with the direction (y-axis direction) substantially orthogonal to the central axis O1 of the hole portion 11. The laminated portion 18a constituting the first portion 16 is an end portion of the connecting piece portion 63 of the L-shaped part 60a among the members constituting the connecting member 10, and the laminated portion 18b is a connection of the L-shaped parts 60b. This is the end of the piece 63. Further, the laminated portion 18c constituting the second portion 17 is a ring 80.

The laminated portion 18a of the first aspect has a structure in which a plurality of fiber layers are laminated with four types of fiber layers each having a different fiber bundle orientation pattern (orientation angle) (hereinafter, this laminated structure is referred to as a differently oriented fiber layer). It may be called a laminated structure) (the same applies to the laminated portion 18b). The orientation pattern of the fiber bundles of each fiber layer constituting the differently oriented fiber layer laminated structure may be three or more. The laminated structure of the laminated portions 18a and 18b is a pseudo-isotropic laminated structure which is the most preferable form among the differently oriented fiber layer laminated structures.

As shown in FIG. 2B, the laminated portions 18a constituting the first portion 16 are laminated in the order of the fiber layers 14a, 14b, 14c, 14d from the center line C to the outside in the z-axis direction (lamination direction). , Each of the fiber layers 14a to 14d contains two types of fiber bundles having different orientation directions. Specifically, the fiber layer 14b is oriented (aligned) in the x-axis direction (hereinafter, the direction along the x-axis (orientation angle) is defined as the 0 ° direction) in the xy plane shown in FIG. 1B. The fiber bundle (hereinafter, may be referred to as 0 ° fiber bundle), and the fiber bundle arranged on the xy plane (hereinafter, may be referred to as 0 ° xy fiber bundle. Here, “xy” is It shall mean the xy plane, and the same applies to "xz" and "yz") and the direction substantially orthogonal to the 0 ° xy fiber bundle arranged outside the 0 ° xy fiber bundle in the z-axis direction. It contains two types of fiber bundles having different orientation directions from the 90 ° xy fiber bundle oriented (90 ° direction shown in FIG. 1B).

Further, the fiber layer 14a arranged on the center line C side (inside) of the fiber layer 14b in the z-axis direction (lamination direction) intersects both the 0 ° xy fiber bundle and the 90 ° xy fiber bundle. The 45 ° xy fiber bundle oriented in the direction (in the case of the first aspect, the 45 ° direction shown in FIG. 1B) and the 0 ° xy fiber bundle arranged inside the 45 ° xy fiber bundle in the z-axis direction. -45 ° aligned in the direction of intersection with any of the xy fiber bundle, 90 ° xy fiber bundle and 45 ° xy fiber bundle (in the case of the first aspect, the −45 ° direction shown in FIG. 1B). It contains two types of fiber bundles having different orientation directions from the xy fiber bundle.

Then, in the laminated portion 18a, the orientation pattern of the fiber direction (orientation angle) of the fiber bundle is set as a symmetrical plane at the center (the interface between the fiber layer 14b and the fiber layer 14c shown in FIG. 2B) in the lamination direction (z-axis direction). The fiber layer 14c and the fiber layer 14d are arranged so that That is, in the laminated portion 18a, the fiber bundles are arranged in the order of −45 °, 45 °, 90 °, 0 °, 0 °, 90 °, 45 °, −45 ° along the central axis O1 (z-axis direction). It is stacked along. Since the fiber bundles included in the axially orthogonal fiber layers 14a and the like are oriented in any direction contained in the xy plane, all of the fibers are oriented in a direction substantially orthogonal to the central axis O1 of the hole portion 11. It is a bundle. According to the connecting member 10 including the first portion 16 composed of the laminated portions 18a and 18b having the pseudo-isotropic laminated structure, the connecting member 10 has sufficient strength against stress acting from multiple directions and is generated after molding. It is possible to suppress problems such as warping. In products such as undercarriage parts for automobiles, the orientation direction (orientation angle) of the fiber bundle may fluctuate due to the presence of bent portions and uneven portions, but fluctuations of about ± 5 ° are allowed. To.

In the case of adopting the above-mentioned differently oriented fiber layer laminated structure, the orientation angles of the fiber bundles contained in the fiber layers 14a and 14d are not limited to 45 ° and −45 °, respectively, and are, for example, 30 ° and −60 °. It may be. That is, the orientation angle of the fiber bundles may be such that the relationship between the orientation angles of the 0 ° xy fiber bundles and the 90 ° xy fiber bundles contained in the fiber layers 14b and 14c satisfies the above conditions (described later). The same applies to the fiber bundles contained in the fiber layers 14f, 14g, 14h and 14i). Further, although the laminated portions 18a and 18b constituting the first portion 16 of the first aspect, which is a preferable form, have been described as an example of a pseudo-isotropic laminated structure, the present invention is not limited to this, and is so-called. It may have an orthogonal laminated structure (the same applies to the third portion 19 described later).

Further, by forming the first portion 16 with the laminated portions 18a and 18b having a pseudo-isotropic laminated structure as described above, it is possible to cope with a multiaxial stress state in which stress from multiple directions acts. Further, the first portion 16 of the first aspect is 0 oriented in the direction (x-axis direction) of the line segment connecting the centers O1 and O2 (see FIG. 1B) of the respective hole portions 11 of the two insertion portions 12. It has fiber layers 14c and 14b containing ° xy fiber bundles. Therefore, even when a load is input to the connecting member 10 in the x-axis direction and a large stress acts on the hole 11 in one direction (shear spindle direction), the stress is in the stress spindle direction (0 ° direction in FIG. 1B). The strength can be improved by the fiber layers 14c, 14b containing the 0 ° xy fiber bundles oriented along the line.

Further, in the case of the first portion 16 composed of the laminated portions 18a and 18b having the pseudo-isotropic laminated structure (differently oriented fiber layer laminated structure) as described above, the fiber bundles whose fiber directions are orthogonal to each other are laminated. It is preferable that they are adjacent to each other along the direction. That is, it is desirable that the 0 ° xy fiber bundle and the 90 ° xy fiber bundle are adjacent to each other along the stacking direction, and similarly, the 45 ° xy fiber bundle and the −45 ° xy fiber bundle are laminated. It is desirable that they are adjacent along the direction. By doing so, for example, even if initial fracture occurs in the fiber layer including the fiber bundle oriented in a certain fiber direction and cracks occur, the fiber bundles adjacent to the cracked fiber bundles are cracked. Since it is orthogonal to the orientation direction of the fiber bundle in which the above is generated, it is possible to prevent cracks generated in the fiber bundle from propagating in the stacking direction (the same applies to the third portion 19 described later). In this respect, in the fiber layer 14a of the first aspect, the −45 ° xy fiber bundle is arranged so as to be adjacent to the 45 ° xy fiber bundle (the same applies to the fiber layer 14d), and in the fiber layer 14b, it is adjacent to the 0 ° xy fiber bundle. -90 ° xy fiber bundles are arranged so as to (the same applies to the fiber layer 14c).

Further, in the insertion portion 12 according to the first aspect, in the direction along the central axis O1 of the hole portion 11 (z-axis direction), the first portion 16 and the second portion 17 are at least the total length L of the hole portion 11. It accounts for more than 25% of. That is, the total of the length (thickness) L1 of the laminated portion 18a constituting the first portion 16 and the length (thickness) L2 of the laminated portion 18b is 25% or more of the total length L of the hole portion 11. .. The length (thickness) L3 of the laminated portion 18c constituting the second portion 17 is 25% or more of the total length L of the hole portion 11. By doing so, the effect of suppressing the breakage of the fiber layer in the outer peripheral portion of the hole portion 11 formed in the insertion portion 12 can be sufficiently exerted.

Further, in the connecting member 10 according to the first aspect, the fiber content of the second portion 17 constituting the insertion portion 12 is 40 to 70% by volume (the same applies to the following modified examples). Here, the fiber content means the ratio of the volume of the fiber bundle to the total volume of the fiber reinforced resin (fiber bundle and resin). By setting the fiber content of the second portion 17 to 40% by volume or more, the effect of suppressing damage to the fiber layer can be sufficiently exerted on the outer peripheral portion of the hole portion 11. Further, by setting the fiber content of the second portion 17 to 70% by volume or less, the fiber layer constituting the second portion 17 can be reliably impregnated with the resin 15, and as a result, the second portion can be impregnated. It is possible to reduce the possibility that voids (vacancy) are generated in 17.

Further, in the insertion portion 12 according to the first aspect, the outer peripheral portion of the hole portion 11 has a direction different from that of the fiber bundles contained in the fiber layers 14a to 14e constituting the first portion 16 and the second portion 17. It is preferable to have a third portion 19 composed of fiber layers 14f to 14i including fiber bundles oriented in. In the insertion portion 12 of the first aspect, the third portion 19 is arranged on the outer periphery of the second portion 17 in a direction substantially orthogonal to the central axis O1 of the hole portion 11.

That is, in the insertion portion 12 according to the first aspect, the third portion 19 is arranged outside the first portion 16 in the direction (z-axis direction) along the central axis O1 of the hole portion 11. In particular, in the connecting member 10 according to the first aspect, the third portion 19 is arranged at the end portion E1 of the hole portion 11 in the z-axis direction.

By doing so, even if a crack is generated in the second portion 17 and the crack extends in the outer peripheral direction of the hole portion 11, the fiber bundle included in the axially parallel fiber layer 14e and the fiber bundle having a different orientation direction are used. The third portion 19 composed of the fiber layers 14f to 14i containing the above can prevent delamination and breakage of the fiber bundle in the fiber layer.

In the insertion portion 12 according to the first aspect, the third portion 19 is composed of a laminated portion 18d in which a plurality of fiber layers are laminated. The stacking direction of the fiber layers constituting the laminated portion 18d coincides with the y-axis direction. The laminated portion 18d of the connecting member 10 of the first aspect, which is a preferable form, has a differently oriented fiber layer laminated structure. Further, the laminated structure of the laminated portion 18d is a pseudo-isotropic laminated structure which is the most preferable form among the differently oriented fiber layer laminated structures. The laminated portion 18d constituting the third portion 19 is an end portion of the back part 70 among the members constituting the connecting member 10 shown in FIGS. 1A to 1C.

That is, as shown in FIG. 2B, the laminated portions 18d constituting the third portion 19 are laminated in the order of the fiber layers 14f, 14g, 14h, 14i from the central axis O1 toward the outside in the y-axis direction (lamination direction). Each of the fiber layers 14f to 14i contains two types of fiber bundles having different orientation directions. Specifically, the fiber layer 14g is arranged in the 0 ° xz fiber bundle and the 0 ° xz fiber bundle on the central axis O1 side (inner surface side) of the 0 ° xz fiber bundle in the y-axis direction (stacking direction) to form the 0 ° xz fiber bundle. It has two types of fiber bundles having different orientation directions, that is, a 90 ° xz fiber bundle oriented in a direction substantially orthogonal to each other.

Further, the fiber layer 14f arranged on the central axis O1 side (inner surface side) of the fiber layer 14g in the y-axis direction (lamination direction) can be used for both 0 ° xz fiber bundles and 90 ° xz fiber bundles. A 45 ° xz fiber bundle oriented in the intersecting direction and a -45 ° xz fiber bundle oriented in the intersecting direction with respect to any of the 0 ° xz fiber bundle, the 90 ° xz fiber bundle, and the 45 ° xz fiber bundle. It has two types of fiber bundles with different orientation directions. Then, in the laminated portion 18d, the orientation pattern of the fiber direction (orientation angle) of the fiber bundle is set with the center of the lamination direction (y-axis direction) (the interface between the fiber layer 14g and the fiber layer 14h shown in FIG. 2B) as a symmetrical plane. The fiber layer 14h and the fiber layer 14i are arranged so as to be symmetrical. That is, the fiber bundles contained in the fiber layers 14f to 14i of the laminated portion 18d constituting the third portion 19 are oriented in any direction included in the xz plane.

Therefore, according to the connecting member 10 including the third portion 19 having the pseudo-isotropic laminated structure, the connecting member 10 has sufficient strength against stress acting from multiple directions and suppresses defects such as warpage generated after molding. Can be done.

<Connecting part>
Next, the structure of the connecting portion of the connecting member according to the first aspect will be described.

As shown in FIG. 3B, the connecting portion 13 according to the first aspect, which is a preferred embodiment, is formed in a substantially T-shaped cross section having an upper side portion 55 and a pillar portion 56, and covers substantially the entire area of the upper side portion 55. It has bent pieces 65a and 65b.

In the connecting member 10 according to the first aspect, which is a preferred embodiment, the connecting portion 13 is the direction (x-axis direction) of the line segment connecting the centers O1 and O2 (see FIG. 1B) of the respective hole portions 11 of the two insertion portions 12. ) Oriented 0 ° xy fiber bundle. By doing so, similarly to the first portion 16 of the first aspect described above, the connecting portion 13 can improve the strength against stress when a load is input in the x-axis direction.

As described above, the connecting portion 13 having a substantially T-shaped cross section is composed of a back part 70 and L-shaped parts 60a and 60b, and the connecting portion 13 is formed by integrating these parts. The back part 70 is composed of the same laminated portion 18d as the laminated portion 18d constituting the third portion 19 (see FIG. 2B) of the above-mentioned insertion portion 12 (that is, the back part portion 70 is composed of the laminated portion 18d). The end portion of the back part 70 in the x-axis direction is the third portion 19 of the insertion portion 12 shown in FIG. 2B). The stacking direction of the fiber layers 14f to 14i constituting the laminated portion 18d coincides with the y-axis direction. Further, the connecting piece portion 63 of the L-shaped part 60a is composed of the same laminated portion 18a as the laminated portion 18a constituting the first portion 16 (see FIG. 2B) of the insertion portion 12 described above (that is,). The end portion of the connecting piece portion 63 of the L-shaped part 60a composed of the laminated portion 18a in the x-axis direction is the first portion 16 of the insertion portion 12 shown in FIG. 2B). The stacking direction of the fiber layers 14a to 14d constituting the laminated portion 18a coincides with the z-axis direction.

The bent piece portion 65a of the L-shaped part 60a is composed of a laminated portion 18e, and the laminated portion 18e is basically the same as the laminated portion 18d, which is a pseudo-isotropic aspect which is the most preferable aspect of the disorientation fiber layer lamination. It has a laminated structure. That is, the laminated portion 18e has fiber layers 14f to 14i, and the fiber layers 14i, 14h, 14g, and 14f are laminated in this order from the lower side of the paper surface along the y-axis direction, which is the stacking direction. The configurations of the 0 ° xz fiber bundle, the 90 ° xz fiber bundle, the 45 ° xz fiber bundle, and the −45 ° xz fiber bundle included in each of the fiber layers 14f to 14i and their effects are as described with respect to the laminated portion 18d. Is.

In the L-shaped parts 60a (60b) constituting the connecting member 10 of the first aspect, one plate-shaped fiber reinforced resin laminated in a pseudo-isotropic laminated structure is shown by a alternate long and short dash line in FIG. 3B. By bending at the folded curve portion, the laminated portion 18a (18b) extending in the y-axis direction, which is the connecting piece portion 63, and the bent piece portions 65a, 65b extending in the z-axis direction from the upper end of the laminated portion 18a (18b). The laminated portion 18e is formed. That is, in the connecting member 10 of the first aspect, the laminated portion 18a (18b) composed of the fiber layers 14a to 14d having the fiber bundles arranged on the xy plane is bent to form the bent piece portion 65a (65b). As a result, a laminated portion 18e composed of fiber layers 14f to 14i having fiber bundles arranged in the xz plane is formed. By doing so, as compared with the case where the laminated portion 18a (18b) and the laminated portion 18e, which are separate bodies, are combined to form the L-shaped part 60a (60b), the L-shaped part 60a (without lowering the strength). 60b) can be formed.

Each of the fiber layers 14a to 14d and 14f to 14i described above has been described as an example in the case where one fiber layer is composed of a plurality of (specifically, two) fiber bundles, but the present invention is limited to this. It's not something. Each fiber layer may contain, for example, only fiber bundles oriented (aligned) in one direction. Specifically, the laminated portion 18a includes a fiber layer containing only 0 ° fiber bundles, a fiber layer containing only 90 ° fiber bundles, a fiber layer containing only 45 ° fiber bundles, and a fiber layer containing only −45 ° fiber bundles. It may have a structure in which the above-mentioned laminated structure is laminated every ~ 18e. In this case, one fiber bundle contains one type of fiber bundle.

Each fiber layer of the fiber-reinforced resin body described above can be constructed by using, for example, a unidirectional material, a non-crimp fabric (NCF) material, a plain weave material, or the like. The non-crimp woven material is a material obtained by laminating a plurality of layers of fiber bundles oriented in a predetermined direction and stitching them with threads such as nylon and polyester. The plain weave material is, for example, a woven set of fiber bundles oriented in directions orthogonal to each other (crossing).

When each fiber layer of the fiber reinforced resin body is composed of a unidirectional material or a non-crimp woven material, the orientation pattern of the fiber bundle should be appropriately set by the laminated structure of the fiber layers as compared with the case of using a plain weave material. Therefore, it is advantageous in that the strength of the fiber-reinforced resin body can be easily adjusted. On the other hand, when each fiber layer of the fiber reinforced resin is composed of a plain weave material, the fibers are difficult to unravel because the fiber bundles are knitted, which is advantageous as compared with the case of using a unidirectional material or a non-crimp woven material. Is.

Further, the type of fiber constituting the fiber bundle included in each fiber layer is not particularly limited, and various fibers such as carbon fiber, synthetic fiber and glass fiber can be used, but the fiber has high mechanical strength and is lightweight. It is preferable to use carbon fiber for the fiber bundle in that a reinforced resin can be obtained.

In the connecting member 10 according to the first aspect, as shown in FIGS. 2B and 3B, a case where the laminated portions 18a to 18e are each composed of four fiber layers has been described as an example. It is not limited to this.

<Manufacturing method of connecting member of the first aspect>
Hereinafter, a method for manufacturing the connecting member of the first aspect will be described. FIG. 4A is a flow showing a manufacturing process of the connecting member according to the first aspect, and FIG. 4B is a shaped body which is an intermediate body of the connecting member formed in a combination process during the manufacturing process of the connecting member according to the first aspect. It is a perspective view which shows each member which comprises (preform).

As shown in FIG. 4A, the method for manufacturing the connecting member according to the first aspect includes a laminating step, a cutting step (S11), a shaping step (S12), a combination step (S13), and a resin impregnation step (S14). This is an example of manufacturing connecting members in this order.

<Laminating and cutting process (S11)>
In the laminating and cutting step (S11), a plurality of fiber sheets including fiber bundles and the like having a predetermined orientation pattern are prepared. Then, a plurality of fiber sheets are laminated. The stacking order of the fiber sheets will be described in detail in the shaping step (S12) below. The laminated fiber sheet is cut into a predetermined size by, for example, a cutting machine (sheet cutter). With the above, the laminating and cutting step (S11) is completed.

<Shaping process (S12)>
In the shaping step (S12), each fiber sheet laminated by the laminating and cutting steps (S11) is heated while being pressurized along the laminating direction using a mold or the like to form a shaped body.

Here, a binder (binding material) such as an epoxy resin is attached to the surface of each fiber sheet. By doing so, it is possible to obtain a shaped body in which the fiber sheets are temporarily bonded to each other by pressurization, and the shaped body does not lose its shape due to handling in a subsequent step or the like. With the above, the shaping step (S12) is completed.

In the connecting member 10 of the first aspect, as shown in FIG. 4B, in the shaping step, the shaping body 100, which is an intermediate body thereof, is used as the shaping bodies 600a and 600b for L-shaped parts and the shaping body for back parts. It is formed by four types of shaped bodies, a shape body 700 and a ring shape shape body 800. Here, each model will be described in detail.

The shaped bodies 600a and 600b for L-shaped parts shown in FIG. 4B are intermediates of the above-mentioned L-shaped parts 60a and 60b (see FIGS. 1A to 3B), and the laminated portions 18a and 18b shown in FIGS. 2B and 3B. , 18e, a fiber sheet containing 45 ° fiber bundles and −45 ° fiber bundles corresponding to the fiber layers 14a, 14f, and a fiber sheet containing 0 ° fiber bundles and 90 ° fiber bundles corresponding to fiber layers 14b, 14g. , Fiber sheets containing 0 ° and 90 ° fiber bundles corresponding to fiber layers 14c, 14h, fiber sheets containing 45 ° and −45 ° fiber bundles corresponding to fiber layers 14d, 14i, FIG. 2B and It is a shaped body formed by laminating in the order shown in FIG. 3B.

In the L-shaped parts shaped bodies 600a and 600b shown in FIG. 4B, two insertion piece portions 602 having through holes 601 and two insertion piece portions 602 arranged at both ends in the x-axis direction are connected to each other. It has a connecting piece portion 603. Further, the shaped body 600a (600b) for L-shaped parts is formed in an L-shaped cross section, and has a bent piece portion 605a (605b) over substantially the entire upper end portion of the connecting piece portion 603. .. The bent piece portion 605a of the shaper 600a for L-shaped parts protrudes in the negative direction on the z-axis, and the bent piece portion 605b of the shaper 600b for L-shaped parts protrudes in the positive direction on the z-axis. The connecting piece 603 of the L-shaped part shaper 600a (600b) is folded into the connecting piece 63 of the L-shaped part 60a (60b) shown in FIG. 3B by folding the L-shaped part shaper 600a (600b). The curved piece portion 605a (605b) corresponds to the bent piece portion 65a (65b) of the L-shaped part 60a (60b) shown in FIG. 3B, respectively.

The shaper 700 for the back part shown in FIG. 4B is an intermediate body of the back part 70 (see FIGS. 1A to 3B) described above, and is formed on the fiber layer 14f constituting the laminated portion 18d shown in FIGS. 2B and 3B. Fiber sheet containing corresponding 45 ° fiber bundle and −45 ° fiber bundle, fiber sheet containing 0 ° fiber bundle and 90 ° fiber bundle corresponding to fiber layer 14g, 90 ° fiber bundle and 0 ° corresponding to fiber layer 14h It is a shaped body formed by laminating a fiber sheet containing a fiber bundle, a -45 ° fiber bundle corresponding to the fiber layer 14i, and a fiber sheet containing a 45 ° fiber bundle in the order shown in FIGS. 2B and 3B. As shown in FIG. 4B, the back part shaper 700 has two pairs (two) of the insertion piece portions 702a and 702b facing each other with the gap 704 interposed therebetween, arranged at both ends in the x-axis direction. It has a connecting piece portion 703 that connects the two sets of insertion piece portions 702a and 702b to each other. The two insertion piece portions 702a and 702b each have a large-diameter hole portion 701. The insertion piece portions 702a and 702b are arranged in a state of being separated by a predetermined spacing dimension through the gap 704 so that the central axes of the large-diameter hole portions 701 are aligned with each other.

The ring shaper 800 shown in FIG. 4B is an intermediate of the ring 80 (see FIGS. 1A to 3B) described above, and is a fiber sheet corresponding to the axially parallel fiber layer 14e constituting the laminated portion 18c shown in FIG. 2B. It is a shaped body formed by laminating in a winding shape. The ring shaper 800 has a substantially cylindrical shape and has a through hole 801. The diameter dimension of the through hole 801 and the diameter dimension of the through hole 601 of the shaped body 600a (600b) for the L-shaped part are substantially the same. Further, the diameter dimension of the large-diameter hole portion 701 of the insertion piece portion 702a (702b) of the back part shaper 700 is larger than the through hole 801 of the ring shaper 800, and is abbreviated as the outer diameter of the ring shaper 800. It is the same.

In addition, the orientation pattern of the fiber bundle included in each of the above-mentioned shape forms for L-shaped parts 600a (600b), shape form 700 for back parts, and shape form 800 for ring is the laminated portion 18a to be formed by the shape form. It corresponds to the orientation pattern of the fiber bundle at ~ 18d and the like.

<Combination process (S13)>
In the combination step (S13), as shown in FIG. 4B, the shapers 600a and 600b for L-shaped parts, the shaper 700 for back parts, and the shaper 800 for rings are appropriately combined. Specifically, the shaped body 600a for L-shaped parts and the shaped body 600b for L-shaped parts are penetrated so that the bent piece portions 605a and 605b project outward from each other and the respective insertion piece portions 602 penetrate. The central axes of the holes 601 are combined so as to coincide with each other.

Next, the upper surface of each of the bent piece portion 605a of the shaper 600a for L-shaped parts and the bent piece portion 605b of the shaper 600b for L-shaped parts and the lower surface of the connecting piece portion 703 of the shaper 700 for back parts are formed. Combine them so that they touch each other. At this time, the insertion piece portions 602 of the L-shaped parts shaped bodies 600a and 600b are sandwiched in the gap 704 between the pair of insertion piece portions 702a and 702b of the back part shaping bodies 700, and L. The central axis of the through hole 601 of the insertion piece 602 of the shape parts 600a and 600b for the character part and the center axis of the large diameter hole 701 of the insertion piece 702a and 702b of the shape form 700 for the back part coincide with each other. To. By doing so, the portion of the shaper 100 (see FIG. 3B) corresponding to the connecting portion 13 before being impregnated with the resin 15 is used for the connecting piece portions 603 and the back part of the shaped bodies 600a and 600b for L-shaped parts, respectively. It is formed by the connecting piece 703 of the shaped body 700. Specifically, the portion of the shaper 100 (see FIG. 3B) corresponding to the upper side portion 55 of the shaper 100 before impregnation with the resin 15 is the bent piece portion 605a, 605b of the shaper 603a (603b) for L-shaped parts. And by the connecting piece 703 of the shaper 700 for the back part, the part of the shaper 100 (see FIG. 3B) corresponding to the pillar 56 is formed by the two connecting pieces 603 of the shaper 603a (603b) for the L-shaped part, respectively. It is formed.

Next, the ring shaper 800 is fitted into the large-diameter hole 701 of the insertion piece portions 702a and 702b of the back part shaper 700, respectively. By doing so, the portion of the shaper 100 (see FIG. 2B) corresponding to the insertion portion 12 before being impregnated with the resin 15 becomes the insert piece portion 602 of the shaper 603a (603b) for the L-shaped part and the portion for the back part. It is formed by the insertion pieces 702a and 702b of the shape 700 and the shape form 800 for the ring. At the same time, the through hole 801 of the ring shaper 800, the through hole 601 of the L-shaped parts 600a and 600b, and the through hole 801 of the ring shaper 800 communicate with each other to form one hole 11 (see FIG. 2B). ) Is formed. From the above, the combination step (S13) is completed, and the shaped body 100 in which the four types of parts are combined can be obtained.

<Resin impregnation step (S14)>
In the resin impregnation step (S14), for example, by resin transfer molding or infusion molding, resin is added to the shaper 100 which is a combination of the shapers 600a and 600b for L-shaped parts, the shaper 700 for back parts, and the shaper 800 for ring. Is impregnated and cured. Through the above steps, the connecting member 10 of the first aspect shown in FIGS. 1A to 3B is completed.

In the method for manufacturing the connecting member 10 of the first aspect, after the shaping step (S12), the shaping bodies 600a and 600b for L-shaped parts and the shaping bodies for back parts, which are the four types of parts shown in FIG. 4B, are used. By having the combination step (S13) in which the 700 and the ring shaper 800 are combined, it is possible to easily manufacture a connecting member or the like having a complicated shape or a fiber bundle having a complicated orientation direction.

As described above, the combination step (S13) may be performed between the shaping step (S12) and the resin impregnation step (S14), or may be performed after the resin impregnation step (S14). Good. When the combination step (S13) is performed between the shaping step (S12) and the resin impregnation step (S14), each shaping body is integrated with the resin, so that the bonding between the shaping bodies should be strengthened. Can be done. On the other hand, when the combination step (S13) is performed after the resin impregnation step (S14), the resin can be impregnated from the surface of each shaped body, so that the resin filling rate can be increased.

(First modification)
Hereinafter, a first modification (hereinafter referred to as a modification 1), which is a preferable modification of the connecting member of the first aspect, will be described with reference to the drawings. In each of the drawings showing the modified example 1, the same or similar components as the connecting member of the first aspect are indicated by the same or similar symbols or reference numbers, and the description will not be repeated in principle and will be omitted (hereinafter, description). The same applies to other modified examples.

Hereinafter, the configuration of the connecting member of the first modification will be described. FIG. 5 is a cross-sectional view of a main part showing a structure of the connecting member according to the first modification, which is cut at a position corresponding to the line AA'in FIG. 1B.

As shown in FIG. 5, the connecting member (fiber reinforced resin body) 20 of the modified example 1 is basically configured in the same manner as the connecting member of the first aspect, but the outer peripheral portion of the hole portion 11, that is, the insertion. Only the structure of the part 22 is different (the same applies to the insertion part of other modified examples). That is, as shown in FIG. 5, in the insertion portion 22 of the modified example 1, a first portion is further outside the second portion 17 in the direction (z-axis direction) along the central axis O1 of the hole portion 11. (Hereinafter, for the sake of understanding, this first part may be referred to as a shaft end: a first part.) 26 is arranged. Specifically, the insertion portion 22 of the modified example 1 has a first portion 16 arranged at the central portion M1 of the hole portion 11 and a shaft end arranged at both end portions E1 in the z-axis direction: first. Part 26, i.e., three first parts 16, 26, and two second parts arranged so as to be sandwiched between the first part 16 and the shaft end: the first part 26, respectively. Has 17.

Therefore, in the first modification, similarly to the connecting member of the first aspect, in the connecting member (fiber reinforced resin body) 20 having the hole portion 11, when a load is input, the outer peripheral portion of the hole portion 11 It is possible to prevent the fiber layers 14a to 14i existing on the outer peripheral portion from being damaged even under the stress expanded due to the stress concentration generated in.

Generally, under a bending load acting in a direction (x-axis direction, y-axis direction) intersecting the central axis O1 of the hole portion 11, shear stress is concentrated in the central portion M1 in the z-axis direction. In this regard, in the insertion portion 22 of the modified example 1, the shaft end: the first portion 26 is further outside the second portion 17 in the direction along the central axis O1 of the hole portion 11 (z-axis direction). Is placed. By doing so, when a bending load is applied, delamination of the fiber layer in the central portion M1 of the hole portion 11 can be prevented in the z-axis direction.

Further, in general, under the above-mentioned bending load, tensile stress or compressive stress is concentrated on the end portion E1 in the z-axis direction. In this respect, in the insertion portion 22 of the modified example 1, the shaft end: the first portion 26 is arranged in the vicinity of the end portion E1 in the z-axis direction. By doing so, it is possible to prevent the fiber layer at the end E1 of the hole 11 from being damaged in the z-axis direction when a bending load is applied.

In the insertion portion 22 of the modified example 1, the laminated structure of the shaft end: the first portion 26 is basically the same as that of the first portion 16. That is, the shaft end: the first portion 26 is composed of laminated portions 18a and 18b in which a plurality of fiber layers are laminated. Shaft end: The lengths (thicknesses) L1 and L2 of the laminated portions 18a and 18b constituting the first portion 26 along the z-axis direction are the strengths required for the outer peripheral portion of the hole portion 11, that is, the insertion portion 12. An appropriate length (thickness) may be set according to the above.

Therefore, in the insertion portion 22 of the modified example 1, the laminated portions 18a and 18b constituting the shaft end: first portion 26 have a differently oriented fiber layer laminated structure as in the laminated portion of the connecting member of the first aspect. It is a pseudo-isotropic laminated structure which is the most preferable form. Further, according to the connecting member 20 including the shaft end: the first portion 26 composed of the laminated portions 18a and 18b having the pseudo-isotropic laminated structure, the connecting member 20 has sufficient strength against stress acting from multiple directions. At the same time, defects such as warpage that occur after molding can be suppressed.

Further, the laminated portion 18a is located near the end portion E1 of the hole portion 11 in the surface portion of the fiber reinforced resin constituting the insertion portion 22 of the modified example 1, that is, in the direction along the central axis O1 of the hole portion 11 (z-axis direction). , 18b, of the fiber layers 14a to 14d, a fiber layer 14d having a 45 ° xy fiber bundle and a −45 ° xy fiber bundle is arranged.

In general, since a complex stress such as bending stress acts on the surface of the fiber reinforced resin constituting the connecting member, that is, in the vicinity of the end E1 of the hole 11 in the z-axis direction, the 0 ° xy fiber bundle and 90 ° When the fiber layers 14b and 14c containing the xy fiber bundle are arranged on the surface, initial fracture is likely to occur in the fiber layer. In this regard, in the insertion portion 22 of the modified example 1, a fiber layer having a −45 ° xy fiber bundle and a 45 ° xy fiber bundle, which are different from both the shear spindle direction and the direction orthogonal to the shear spindle direction, on the surface portion. 14d is arranged. In this way, by arranging a fiber layer having a fiber bundle oriented in a direction different from both the shear spindle direction and the direction orthogonal to the shear spindle direction on the surface of the fiber-reinforced resin, the fiber layer against stress acting in a complex manner It is preferable because it can suppress the occurrence of initial fracture inside (the same applies to the connecting member of the second modification). A fiber layer 14a including a 45 ° xy fiber bundle and a −45 ° xy fiber bundle may be arranged on the surface of the fiber reinforced resin as in the fiber layer 14d.

In the insertion portion 22 of the first modification, the laminated portions 18c and 18d are the connecting members of the first aspect shown in FIG. 2B, except that the lengths (thicknesses) L3 and L4 along the z-axis direction are different. It has the same structure as the laminated portions 18c and 18d of. That is, in the insertion portion 22 of the modified example 1, the second portion 17 is composed of a laminated portion 18c in which a plurality of fiber layers are laminated. Further, the third portion 19 is composed of a laminated portion 18d in which a plurality of fiber layers are laminated.

In the insertion portion 22 according to the first modification, the first portion 16 (26) and the second portion 17 each occupy at least 25% or more of the total length L of the hole portion 11 in the z-axis direction. That is, for the three arranged first portions 16 and 26, the length (thickness) L5 and L6 of the first portion 16 in the z-axis direction and the shaft end: the length (thickness) of the first portion 26. The total of L1 and L2 may be 25% or more of the total length L of the hole 11. Further, for the second portion 17 arranged in the z-axis direction, the total length (thickness) L3 and L4 of each may be 25% or more of the total length L of the hole portion 11. By doing so, similarly to the connecting member of the first aspect, the insertion portion 22 (connecting member 20) of the modified example 1 also sufficiently exerts the effect of suppressing damage to the fiber layer at the outer peripheral portion of the hole portion 11. can do.

(Second modification)
Hereinafter, a second modification (hereinafter referred to as a modification 2), which is another preferable modification of the connecting member of the first aspect, will be described with reference to the drawings. FIG. 6 is a cross-sectional view of a main part showing a structure of the connecting member according to the second modification, which is cut at a position corresponding to the line AA'in FIG. 1B.

As shown in FIG. 6, the connecting member 30 of the modified example 2 is different from the connecting member of the first aspect in the arrangement of the first portion 26, the second portion 17, and the like constituting the insertion portion 32. That is, as shown in FIG. 6, in the insertion portion 32 of the modified example 2, the second portion 17 is arranged in the central portion M1 of the hole portion 11 in the direction (z-axis direction) along the central axis O1 of the hole portion 11. The shaft end: the first portion 26 is arranged at the end portion E1 of the hole portion 11. Specifically, the connecting member 30 of the modified example 2 removes the two first portions 16 arranged in the central portion M1 of the insertion portion 22 of the modified example 1 shown in FIG. 5, as shown in FIG. A connecting member 30 having an insertion portion 32 in which a second portion 17 is arranged in the central portion M1.

Therefore, in the second modification, similarly to the connecting member of the first aspect, when a load is input to the connecting member (fiber reinforced resin body) 30 having the hole portion 11, the outer peripheral portion of the hole portion 11 It is possible to prevent the fiber layers 14a to 14i existing on the outer peripheral portion from being damaged even under the stress expanded due to the stress concentration generated in.

Generally, under a bending load, tensile stress or compressive stress is concentrated on the end E1 in the z-axis direction. In this respect, in the connecting member 30 of the modified example 2, the shaft end: the first portion 26 is arranged in the vicinity of the end portion E1 of the insertion portion 32 in the z-axis direction. By doing so, it is possible to prevent the fiber layer at the end E1 of the hole 11 from being damaged in the z-axis direction when a bending load is applied.

In the connecting member 30 of the modified example 2, the basic configuration of the insertion portion 32 is the same as that of the first aspect or the insertion portion of the modified example 1, and the second portions 17 and the third portions constituting the insertion portion 32. The configuration is the same as that of the connecting member of the first aspect shown in FIG. 2B, except that the length (thickness) L3 along the z-axis direction of 19 is different. That is, the shaft end: the first portion 26 constituting the insertion portion 32 is composed of laminated portions 18a and 18b in which a plurality of fiber layers are laminated. Further, the second portion 17 is composed of a laminated portion 18c in which a plurality of fiber layers are laminated, and the third portion 19 is composed of a laminated portion 18d in which a plurality of fiber layers are laminated. Therefore, in the connecting member 30 of the modified example 2, in addition to being able to prevent damage to the fiber layer at the end E1 of the hole 11 of the insertion portion 32, as in the connecting member of the modified example 1, the connecting member of the modified example 1 can be prevented from being damaged. The configuration can be simplified and the manufacturing cost can be reduced.

(Third modification example)
Hereinafter, a third modification of the connecting member (hereinafter referred to as a modification 3), which is still another preferable modification of the first aspect, will be described with reference to the drawings. FIG. 7 is a cross-sectional view of a main part showing a structure of the connecting member according to the third modification, which is cut at a position corresponding to the line AA'in FIG. 1B.

As shown in FIG. 7, the connecting member 40 of the modified example 3 is basically configured in the same manner as the connecting member of the first aspect, but the connecting member 40 of the modified example 3 has an insertion portion 42 (hole). The outer peripheral portion of the portion 11) is different from the connecting member of the first aspect in that it further has a foaming material 41. That is, in the insertion portion 42 of the modified example 3, the fiber layers 14a and 14b, which are a part of the fiber layers constituting the first portion 16 of the first aspect shown in FIG. 2B, are foamed as shown in FIG. It is replaced with the material 41.

Therefore, in the third modification, similarly to the connecting member of the first aspect, when a load is input to the connecting member (fiber reinforced resin body) 40 having the hole portion 11, the outer peripheral portion of the hole portion 11 It is possible to prevent the fiber layers 14c to 14i existing on the outer peripheral portion from being damaged even under the stress expanded due to the stress concentration generated in.

Further, in the connecting member 40 of the modified example 3, in addition to the same configuration as the connecting member of the first aspect, the outer peripheral portion of the hole portion 11 further has a foaming material 41. In particular, in the connecting member 40 of the modified example 3, which is a preferable form, a part of the fiber bundle constituting the first portion 16 is replaced with the foaming material 41. By doing so, in addition to the same effect as that of the connecting member of the first aspect, the fiber bundles used can be reduced to reduce the manufacturing cost, and the weight of the connecting member can be reduced. Hereinafter, the connecting member 40 of the modified example 3 will be described in detail.

The first portion 16 of the modified example 3 is composed of laminated portions 48a and 48b in which a plurality of fiber layers are laminated. The laminated portions 48a and 48b are composed of two fiber layers, a fiber layer 14c containing 90 ° and 0 ° fiber bundles oriented in the xy plane and a fiber layer 14d containing -45 ° and 45 ° fiber bundles, respectively. There is. Then, the fiber layers 14a and 14b constituting the laminated portions 18a and 18b in the connecting member 10 of the first aspect shown in FIG. 2B are changed to the hole portion 11 in the z-axis direction in the connecting member 40 of the modified example 3 shown in FIG. It is replaced with the foaming material 41 arranged in the central portion M1 of the above, and is sandwiched between the laminated portions 48a and 48b composed of the fiber layers 14c and 14d.

Therefore, the lengths (thicknesses) L8 and L9 of the laminated portions 48a and 48b of the modified example 3 along the z-axis direction are the lengths (thickness) L1 of the laminated portions 18a and 18b of the first aspect shown in FIG. 2B. It is shorter (thinner) than L2, and the length (thickness) of the difference, that is, (L1 + L2)-(L8 + L9) is the length (thickness) L7 of the foam material 41.

The foam material 41 is preferably made of a material having excellent insulating properties and cushioning properties. As the foaming material 41, for example, a resin such as polyethylene foam, polystyrene foam, urethane foam, or acrylic foam can be used.

(Example)
Hereinafter, the present invention will be described in more detail with reference to FIGS. 8 to 10 based on examples, but the present invention is not limited to these examples. 8A is a cross-sectional view showing a test piece of an example according to the present invention, FIG. 8B is a cross-sectional view showing a test piece of Comparative Example 1, and FIG. 8C is a cross-sectional view showing a test piece of Comparative Example 2. 9 is a schematic diagram illustrating a test method for the test pieces shown in FIGS. 8A to 8C, and FIG. 10 is a graph showing test results of Examples and Comparative Examples. In FIGS. 8A to 8C, the direction perpendicular to the paper surface is the x-axis direction, the horizontal direction is the y-axis direction, and the vertical direction is the z-axis direction.

As Example 1, a flat plate-shaped test piece 30a shown in FIG. 8A corresponding to the configuration of only the insertion portion 32 among the connecting member (fiber reinforced resin body) 30 of the modified example 2 shown in FIG. 6 was produced and described in detail below. It was subjected to a bending strength test. As shown in the vertical cross-sectional view of FIG. 8A, the test piece 30a is a flat plate-shaped test piece, and is a flat plate along the central axis O1 so as to include the hole 11 in the substantially cylindrical insertion portion 32 shown in FIG. The test piece 30a shown in FIG. 8A is a model equivalent to the insertion portion 32 shown in FIG. 6 in evaluating the bending strength because it is drawn out in a shape.

The test piece 30a of Example 1 is arranged at both ends in the z-axis direction: a first portion 26, a second portion 17, a third portion 19, and both ends in the z-axis direction. Shaft end: Consists of a fourth portion 90 arranged for the purpose of supporting the first portion 26. Shaft end: The first portion 26 is formed by a laminated portion 18a and a laminated portion 18b made of axially orthogonal fiber layers, the second portion 17 is formed by a laminated portion 18c made of axial parallel fiber layers, and the third portion 19 is formed by a laminated portion 18c. Shaft end: The fourth portion 90 is formed by a laminated portion 18d composed of a fiber layer containing fiber bundles oriented in different directions from the fiber bundles contained in the fiber layers constituting the first portion 26 and the second portion 17. , Each is composed of a laminated portion 18a composed of axially orthogonal fiber layers. The detailed laminated structure (arrangement of 0 °, 90 °, 45 °, −45 ° fiber bundles) of the laminated portions 18a to 18d is basically as described above. Further, as a fiber sheet used as a material for forming the laminated portions 18a to 18d, a Toray T800 unidirectional carbon fiber sheet having a thickness of 0.16 mm was used.

As shown in FIG. 8A, the size of the flat plate-shaped test piece 30a was 80 mm in the y-axis direction, 4.8 mm in the thickness in the z-axis direction, and 15 mm in the width in the x-axis direction. Then, in the bending test, the hole portion 11 having a diameter of φ3 mm is placed on the center line of the test piece 30a in the x-axis direction and the test piece in the y-axis direction so that the hole portion 11 is arranged at the portion where the shear stress is maximum. The central axis O1 was arranged at a position 20 mm from the right end of 30a. The total length (thickness) of the hole 11 in the z-axis direction is 4.8 mm, whereas the total length of the two shaft ends: the first portion 26 is 1.3 mm (27% of the total length), and the second portion. The length of 17 was 3.5 mm (73% of the total length). As the binder to be attached to the fiber sheet, Griltex2AP manufactured by EMS, which is a polyamide-based hot melt adhesive, was used. As the resin 15 constituting the test piece 30a, a Z1 epoxy resin manufactured by Nissin Resin containing a curing agent was used. Using the above materials, a test piece 30a having a carbon fiber content of 57% by volume was prepared according to the method for producing a fiber-reinforced resin body described above.

<Comparison example>
As Comparative Example 1, in the test piece 30a shown in FIG. 8A, the portion of the second portion 17 (laminated portion 18c) and the portion of the third portion 19 (laminated portion 18d) is replaced with the portion of the fourth portion 90 (laminated portion 18a). The test piece 30b shown in FIG. 8B was prepared by replacing with. Further, as Comparative Example 2, in the test piece 30b shown in FIG. 8B, the inner diameter is φ3 mm, the outer diameter is φ9 mm, and the thickness is 0 between the fiber layers of the laminated portion 18a constituting the fourth portion 90. The fifth portion 91, which is .32 mm and has a substantially annular shape when viewed from the z-axis direction, is arranged at four locations in the z-axis direction so that the central axis coincides with the central axis O1 of the hole portion 11. The test piece 30c shown in FIG. 8C was prepared. The fifth portion 91 is composed of a laminated portion 18e composed of fiber layers laminated so that fiber bundles are wound around the pore portion 11 in the circumferential direction, and the fiber reinforcement described in Patent Document 1 This is a test piece that imitates the laminated structure of the outer peripheral portion of the hole portion of the resin body.

[Bending strength test]
The breaking strengths of the test pieces 30a according to the formed Examples and the test pieces 30b and 30c according to the Comparative Examples were evaluated by the bending strength test shown in FIG. Specifically, as shown in FIG. 9, the test pieces 30a to 30c were placed on two fulcrums 101 having a distance between fulcrums of 60 mm, and a load was applied from above by an indenter 102. The speed of the indenter 102 was 1 mm / min, and the load at the time of breaking of the test piece was measured to obtain the bending stress at the time of breaking of the test pieces 30a to 30c. The test pieces 30a to 30c were arranged so that the central axis of the hole 11 was aligned with the pressing direction of the indenter 102 at the time of the test.

<Test results>
FIG. 10 is a graph showing the breaking strength of the test pieces 30a according to the example and the test pieces 30b and 30c according to the comparative example. As shown in FIG. 10, when the bending stress at the time of breaking of the test piece 30a of Example 1 is 1.0, the bending stress of the test piece 30b of Comparative Example 1 at the time of breaking is 0.88. The bending stress of the test piece 30c of Comparative Example 2 at the time of fracture was 0.90. The starting point of failure of the test pieces 30a to 30c was the outer peripheral portion of the hole portion 11 shown in FIGS. 8A to 8C.

From the above results, the test piece 30a of the example to which the structure of the fiber-reinforced resin body according to the present invention was applied had the breaking strength of the outer peripheral portion of the hole 11 with respect to the test pieces 30b and 30c of the comparative example to which the structure of the fiber-reinforced resin body was not applied. Was shown to have increased.

The present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the gist thereof.

10, 20, 30, 40 Connecting member (fiber reinforced plastic body)
30a, 30b, 30c Test piece 11 Holes 12, 22, 32, 42 Insertion 13 Connecting parts 14, 14a, 14b, 14c, 14d, 14e, 14f, 14g, 14h, 14i Fiber layer 15 Resin 16,26 First Part 17 Second part 18a, 18b, 18c, 18d, 18e, 48a, 48b Laminated part 19 Third part 55 Upper side 56 Pillar part 41 Foaming material 60a, 60b L-shaped part 63 Connecting piece part 65a, 65b Folded Song piece 70 Back part 80 Ring

Claims (14)

A fiber-reinforced resin body having a plurality of fiber bundles and a resin impregnated between the plurality of fiber bundles.
Has a hole and
The outer peripheral portion of the hole includes a first portion containing a fiber bundle oriented in a direction substantially orthogonal to the extension axis of the hole, and a fiber bundle oriented in a direction along the extension axis of the hole. A fiber-reinforced resin body characterized by having a second portion. In the fiber-reinforced resin body according to claim 1,
The first portion is arranged at the center of the hole in the direction along the extension axis of the hole, and the second portion is arranged outside the first portion. Fiber reinforced resin body. In the fiber-reinforced resin body according to claim 2,
A fiber-reinforced resin body characterized in that the first portion is further arranged outside the second portion in a direction along the stretching axis of the hole portion. In the fiber-reinforced resin body according to claim 1,
A fiber characterized in that the second portion is arranged at the central portion of the hole portion and the first portion is arranged at the end portion of the hole portion in a direction along the stretching axis of the hole portion. Reinforced resin body. In the fiber-reinforced resin body according to any one of claims 1 to 4.
A fiber-reinforced resin body, wherein each of the first portion and the second portion occupies at least 25% or more of the total length of the pore portion in a direction along the stretching axis of the hole portion. In the fiber-reinforced resin body according to any one of claims 1 to 5,
A fiber-reinforced resin body characterized in that the fiber content of the second portion is 40 to 70% by volume. In the fiber-reinforced resin body according to any one of claims 1 to 6,
A fiber-reinforced resin body characterized in that the outer peripheral portion of the hole portion further has a foaming material. In the fiber reinforced resin body according to claim 7.
A fiber-reinforced resin body characterized in that a part of the fiber bundle constituting the first portion is replaced with the foaming material. In the fiber-reinforced resin body according to any one of claims 1 to 8.
The outer peripheral portion of the hole portion further has a third portion including a fiber bundle oriented in a direction different from the fiber bundle contained in the first portion and the second portion, respectively.
A fiber-reinforced resin body characterized in that the third portion is arranged on the outer periphery of the second portion in the circumferential direction of the drawing shaft of the hole portion. In the fiber-reinforced resin body according to claim 9,
The third portion comprises a plurality of laminated fiber layers.
The laminated structure of the third portion is a fiber-reinforced resin body characterized by having a pseudo isotropic laminated structure. In the fiber-reinforced resin body according to any one of claims 1 to 10.
The first portion comprises a plurality of laminated fiber layers.
The laminated structure of the first portion is a fiber-reinforced resin body characterized by having a pseudo isotropic laminated structure. In the connecting member having the fiber reinforced resin body according to any one of claims 1 to 11.
A connecting member having two insertion portions having the holes and a connecting portion for connecting the two insertion portions to each other. In the connecting member according to claim 12,
The connecting portion is a connecting member including a fiber bundle oriented in the direction of a line segment connecting the centers of the holes of the two insertion portions. In the connecting member according to claim 12 or 13,
The first portion is a connecting member including a fiber bundle oriented in the direction of a line segment connecting the centers of the holes of the two insertion portions.

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