JPH09254266A - Bolt and nut made of fiber reinforced resin material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-magnetic bolt allowed to approach a synthetic resin in the coefficient of linear expansion and satisfying various conditions of electric insulating properties, corrosion resistance and wt. reduction by forming the first fiber member in the shaft part of a bolt made of a fiber reinforced resin material by arranging a plurality of org. fibers along the axial direction of the bolt. SOLUTION: A bolt 10 made of a fiber reinforced resin material has a head 11 and a shaft part 12 and the internal structure of the shaft part 12 is formed by embedding a large number of reinforcing fibers 22 in a matrix 21 over the almost total length of the bolt. The reinforcing fibers 22 are mutually arranged along the axial direction of the bolt 10 at an almost uniform interval. As the material of the matrix 21, an epoxy resin is used and, as the reinforcing fibers 22, carbon fibers are used. The diameter of each of carbon fibers is several μm-10μm and long fibers are parallelly arranged in the axial direction of the bolt in the shaft part where the axial tensile force of the bolt 10 is excellent.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a bolt and a nut made of a fiber reinforced resin material.

[0002]

2. Description of the Related Art Conventionally, bolts and nuts are often used to fasten members and parts to facilities, vehicles, or equipment of railways, roads, or general industries. Steel is mainly used for the material of these bolts and nuts from the viewpoint of strength and economy.

[0003]

However, steel is a ferromagnetic material, which is magnetized when a magnetic field acts and receives a force in the direction of the magnetic field. For this reason, for example, if steel bolts are used to fasten the ground coil of a levitation railway, there is a risk of adversely affecting the traveling of the levitation vehicle. To receive repeated force,
There is a problem that the bolt axial force fluctuates greatly and there is a possibility of fatigue and loosening of fastening force.

Further, the ground coil of the levitation railway is housed in a plastic sealed body. Since the linear expansion coefficient of steel and the linear expansion coefficient of plastic are different, distortion occurs due to the difference in expansion amount with changes in environmental temperature, and this causes stress, which results in large fluctuations in bolt axial force.
There was also a problem.

Although steel is a good conductor of electricity, there are also fastening points where electrical insulation is required. Further, steel corrodes due to water and chemical components, but there are many environments under fastening conditions that require corrosion resistance. Further, if the condition of having the same strength as steel is satisfied, the merit of being lighter than steel is very large.

The present invention has been made to solve the above problems, and the problems to be solved by the present invention are non-magnetic, have a linear expansion coefficient close to that of synthetic resin, and have electrical insulation, corrosion resistance, and An object of the present invention is to provide a fastener that can satisfy the conditions for weight reduction.

[0007]

In order to solve the above-mentioned problems, a first fiber-reinforced resin material bolt according to the present invention comprises:
By embedding a first fiber member in a first base material made of synthetic resin and forming the first base material by a first fiber-reinforced resin material having increased strength, and by screwing the nut with a nut. In a bolt made of a fiber-reinforced resin material, which is configured to fasten an object to be fastened to a fastened object and to mitigate a change in axial force due to a change in magnetic field or temperature, the first bolt in the shaft portion of the bolt made of the fiber-reinforced resin material. The fibrous member is a plurality of long fibers arranged along the axial direction of the bolt made of the fiber-reinforced resin material.

In the second fiber-reinforced resin material bolt according to the present invention, the first fiber member is embedded in the first base material made of synthetic resin to increase the strength of the first base material. Fiber reinforced formed by the first fiber reinforced resin material that has been made to be screwed with a nut to fasten the object to be fastened to the fastened object, and to mitigate fluctuations in axial force due to changes in magnetic field or temperature. In the resin material bolt, the first fiber member in the shaft portion of the fiber reinforced resin material bolt has a plurality of long fibers knitted in a substantially rope shape along the axial direction of the fiber reinforced resin material bolt. It is characterized by being arranged in.

Further, in the third fiber-reinforced resin material bolt according to the present invention, the first fiber member is embedded in the first base material made of synthetic resin to increase the strength of the first base material. Fiber reinforced formed by the first fiber reinforced resin material that has been made to be screwed with a nut to fasten the object to be fastened to the fastened object, and to mitigate fluctuations in axial force due to changes in magnetic field or temperature. In the resin material bolt, the first fiber member in the shaft portion of the fiber reinforced resin material bolt is a plurality of short fibers arranged three-dimensionally.

In the above fiber reinforced resin material bolt, preferably, the first fiber member in the head portion of the fiber reinforced resin material bolt has reinforcing fibers formed by arranging long fibers in a strip shape. A plurality of reinforcing cloths are formed by knitting in a substantially checkered pattern and are laminated and arranged in the axial direction of the fiber-reinforced resin material bolts.

Further, preferably, the first fiber member in the head portion of the fiber-reinforced resin material bolt is a plurality of short fibers which are three-dimensionally distributed and arranged.

Further, preferably, in the bolt made of a fiber reinforced resin material, the long fiber or the short fiber is a fiber made of any one of carbon, glass, aramid resin, boron, titanium, alumina and polyvinyl alcohol. Including combinations of these fibers.

In the nut made of the first fiber reinforced resin material according to the present invention, the strength of the second base material is increased by embedding the second fiber member in the second base material made of synthetic resin. It is formed of the second fiber-reinforced resin material, and is configured to fasten the object to be fastened to the object to be fastened by being screwed into the bolt, and to mitigate fluctuations in the axial force of the bolt due to changes in the magnetic field or temperature. In the nut made of fiber reinforced resin material,
The second fiber member in the fiber-reinforced resin material nut is formed by braiding reinforcing tapes formed by arranging long fibers in a strip shape in a substantially checkered pattern, and a shaft of the fiber-reinforced resin material nut. It is characterized in that it is a plurality of reinforcing cloths laminated in the direction.

In the nut made of the second fiber reinforced resin material according to the present invention, the strength of the second base material is increased by embedding the second fiber member in the second base material made of synthetic resin. It is formed of the second fiber-reinforced resin material, and is configured to fasten the object to be fastened to the object to be fastened by being screwed into the bolt, and to mitigate fluctuations in the axial force of the bolt due to changes in the magnetic field or temperature. In the nut made of fiber reinforced resin material,
The second fiber member in the nut made of a fiber-reinforced resin material is a plurality of short fibers that are three-dimensionally dispersed and arranged.

In the nut made of the fiber reinforced resin material, preferably, the long fiber or the short fiber is a fiber made of any one of carbon, glass, aramid resin, boron, titanium, alumina and polyvinyl alcohol. Including combinations of these fibers.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a view showing the structure of a bolt which is an embodiment of a fiber reinforced resin material bolt according to the present invention, and FIG. 1 (A) is a partial cutaway side view of the bolt. 1
1B is a partially cutaway front view of the head of the bolt shown in FIG. 1A, and FIG. 1C is a conceptual diagram showing a method for producing the reinforced cloth shown in FIG. 1B. ing.

As shown in FIG. 1 (A) and FIG. 1 (B), the bolt 10 has a head portion 11 and a shaft portion 12. The head portion 11 is formed in a substantially hexagonal column shape having a low height. A circular through hole 15 penetrating in the axial direction of the pillar is formed in the head 11. Further, the shaft portion 12 is the head portion 11.
The cylindrical portion 14 inserted and fixed in the through hole 15 of the
And a male screw portion 13 connected to the columnar portion 14.

The internal structure of the shaft portion 12 is shown in FIG.
As shown in the lower half part of (A) and the center of the right half part of FIG. 1 (B), a plurality of reinforcing fibers 22 are embedded in the matrix 21 as a base material over substantially the entire length of the bolt. The reinforcing fibers 22 are arranged along the axial direction of the bolt 10 at substantially uniform intervals.

An epoxy resin is used as the material of the matrix 21. Further, as the reinforcing fiber 22,
Carbon fiber is used. The diameter of carbon fiber is several μm
About 10 μm. The tensile strength of carbon fiber is
It is about 70 to 350 kg / mm ² . This carbon fiber
It is formed by carbonizing a distillation residue of rayon, petroleum or coal, or a raw yarn made from polyacrylonitrile (PAN) as a raw material by heating at high temperature.

Looking at the internal structure of the head 11 of the bolt, as shown in the lower half of FIG. 1A and the center of the right half of FIG. A plurality of reinforcing cloths 24 are laminated and embedded in 23. The stacking direction of the reinforcing cloth 24 is the axial direction of the bolt 10. Each of the reinforcing cloths 24 has a flat plate shape or a cloth shape, and as shown in FIG. 1 (C), narrow band-shaped reinforcing tapes 25 are formed by braiding each other in a substantially checkered pattern.
Further, each reinforcing tape 25 has reinforcing fibers 27 aligned in a line to form a strip or sheet as a whole, and a matrix 26 fills spaces between and around each reinforcing fiber 27.

The material of the matrix 23 or 26 is similar to that of the matrix 21 described above, and the material of the reinforcing fiber 27 is similar to that of the reinforcing fiber 22 described above.

The material formed as described above is a fiber reinforced resin material (FRP).
CFRP (Carbon Fiber Reinforced Plastics) when the fibers embedded in the base material are carbon fibers, and GFRP (Glass Fiber Reinforced Plastics) when the fibers are glass fibers.
Plastics). These fiber reinforced resin materials significantly increase the strength of the base material. Generally, the tensile strength in the fiber direction is about 30 times that of the base material alone, the elastic modulus in the fiber direction is about 15 to 30 times that of the base material alone, and the linear expansion coefficient in the fiber direction is the base material alone. In this case, the value is about 1/10 or less.

However, the fiber reinforced resin material has a very low strength in the direction perpendicular to the fiber direction and exhibits anisotropy. Therefore, as in the bolt 10 of the present embodiment, long fibers are arranged in parallel in the axial direction of the bolt in the shaft portion where the axial tensile force is predominant, and the bolt head that may be subjected to complicated stress such as twisting or compression. If the portion is configured to be pseudo-isotropic by the laminated arrangement of the reinforcing cloth, the stress acting on the bolt can be effectively coped with.

Next, an outline of a method of forming the above-described bolt 10 will be described. First, the shaft 12 of the bolt
Prepared is one in which the synthetic resin 21 of the matrix is impregnated into the reinforcing fibers 22 in advance, and these are bundled into a round bar shape and cured by heating and compression in a columnar mold or the like, and a substantially round bar shape round bar material ( (Not shown). This round bar material is cut into a predetermined length to form a shaft material (not shown) that is the original shape of the shaft.

On the other hand, prepared is one in which the synthetic resin 26 of the matrix is impregnated in the reinforcing fibers 27 in advance, and these are closely arranged so as to be in a line with each other and cured by heating and compression in a flat plate press or the like, The reinforcing tape 25 is formed. Next, the synthetic resin 23 of the matrix is prepared by impregnating the surface or the edge of the reinforcing tape 25 in advance, and these are knitted in a substantially checkered pattern, and are heated and compressed by a flat plate press or the like. It is cured to form the reinforcing cloth 24. Next, the synthetic resin 23 of the matrix is preliminarily impregnated on the surface of the reinforcing cloth 24 and the like, and these are laminated on each other and hardened by heating and compressing in a flat plate press or the like to obtain a thick plate material ( (Not shown).

Next, a member having a substantially hexagonal columnar shape is cut out from the above thick plate material, and a through hole 15 is opened in the center to form a bolt head 11. Next, the inside of the through hole 15 and one end of the above-mentioned shaft material (not shown) are impregnated with a matrix in advance, and after the shaft material is inserted into the through hole 15, the material is cured by heat compression or the like, and the bolt is A raw material (not shown) is formed. Finally, use a lathe etc. to attach the male screw 1 to the tip of the shaft.
3 is cut and the bolt 11 is formed.

The above bolt forming method is an example, and the bolt can be formed by other methods. For example, the matrix 21 is formed on the reinforcing fiber 22 having the same length as the bolt shaft portion 12.
Prepared by impregnating them in advance and bundling them into a round bar shape, and when heat-compressing them in a mold or the like, a female screw is formed on the inner surface of the mold, and the shaft portion 12 is hardened.
May be directly molded. The subsequent steps are the same as above.

Further, in the same manner as described above, the bolt head 1 having a through hole 15 in the center is made of a fiber reinforced resin material.
After forming No. 1, a female screw can be cut on the inner wall of the through hole 15 using a lathe or the like to form a nut (not shown).

Next, another embodiment of the present invention will be described. 2A and 2B are views showing an example of attachment of a member using a bolt which is another embodiment of the present invention. FIG. 2A shows a state before attaching the member and FIG. 2B shows after attaching the member. The respective states are shown.

As shown in the figure, the bolt 10A has a fixing portion 16, a cylindrical portion 14A, and a male screw portion 13A. The fixing portion 16 has a shape similar to a deformed bar, and a spiral or annular rib (projection) is provided on the peripheral surface of a round bar-shaped main body.

Although not shown, a plurality of reinforcing fibers (long fibers) are knitted in a substantially rope shape inside the bolt 10A so that the rope member (not shown) extends along the axial direction of the bolt. It is installed in. In this bolt 10A, epoxy resin is used as the matrix and glass fiber is used as the reinforcing fiber. That is, the bolt 10A is made of glass fiber reinforced plastic (GFR).
P) bolts.

The glass fiber is formed by using a so-called E glass or a so-called S glass containing almost no alkali component as a raw material and rapidly cooling the molten glass while stretching it. The glass fiber (long fiber) has a diameter of about several μm to 20 μm. The tensile strength of glass fiber is
E glass is about 350 kg / mm ² , and S glass is about 500 kg / mm ² .

In the bolt 10A, the rope member (not shown) is impregnated with an epoxy resin (not shown), and a round bar material (not shown) is formed by heat compression molding or the like. It is formed by cutting the male screw portion of the bolt from this material.

Next, an example of member attachment using the bolt 10A will be described. First, the fixing portion 16 is embedded in the concrete wall C and fixed to the concrete wall C in a state where the male screw portion 13A of the bolt 10A projects outward (FIG. 2).
(A)).

Next, the spacer 10 for adjustment is attached to the bolt 10A.
3 through the bolt hole of the levitation railway propulsion coil 42, and then the levitation railway levitation coil 41 bolt hole, and the nut 30 is screwed and fastened (FIG. 2B).
reference). The change over time of the axial force value of the bolt 10A in this case was measured by a washer-type load cell 50. Also, for comparison, the same load cell was attached to an ordinary steel bolt, and the change with time of the axial force value was measured.

FIG. 3 shows the measurement results of the axial force, temperature and time of each bolt in the above case. In FIG. 3, the curve a is the axial force value of the high manganese steel bolt, the curve b is the axial force value of the GFRP bolt 10A of the embodiment of FIG. 2, the curve c is the temperature value, and the curve d is for levitation. The values of the surface temperature of the coil 41 are shown respectively.

As shown in the figure, the axial force of the high manganese steel bolt (curve a) and the axial force of the GFRP bolt 10A (curve b) also fluctuate as the temperature changes day and night (curve c).
However, regarding the magnitude of the fluctuation of the axial force, GFR
The fluctuation value in the axial force (curve b) of the P bolt 10A is
About 1 of fluctuation value of axial force (curve a) of high manganese steel bolt
It has been reduced to a value of / 3, and it can be seen that there is a remarkable effect of alleviating the fluctuation of the bolt axial force due to the temperature change.

Further, in both the embodiment shown in FIG. 1 and the embodiment shown in FIG. 2, since the bolts and nuts are made of a non-magnetic material, they do not adversely affect the traveling of the levitation type vehicle and the levitation is prevented. Even if a high magnetic field fluctuation occurs near the bolt due to traveling of the vehicle, the bolt axial force is not subjected to a large force that fluctuates. Furthermore, plastic has all the above-mentioned requirements for a fastener, that is, it is an excellent electrical insulator, has corrosion resistance, and is lightweight.

In the embodiment of FIG. 1 described above, the matrices 21, 23 and 26 correspond to the first base material, and the reinforcing fiber 22 and the reinforcing cloth 24 correspond to the first fiber member. Further, in the above-described embodiment of FIG. 2, the epoxy resin (not shown) corresponds to the first base material, and the rope-shaped member (not shown) corresponds to the first fiber member. Also,
In the embodiment of FIG. 2 described above, the levitation coil 41,
The propulsion coil 42 and the spacer 43 correspond to an object to be fastened,
The concrete wall C corresponds to a fastener.

The present invention is not limited to the above embodiments. Each of the above embodiments is merely an example, and has substantially the same configuration as the technical idea described in the claims of the present invention, and those having the same functions and effects are:
Anything is included in the technical scope of the present invention.

For example, in the embodiment shown in FIG. 1, long fibers are arranged in the axial direction of the bolt shaft portion and embedded in the base material, and a reinforcing cloth is laminated in the bolt head portion and embedded in the base material. A bolt made of fiber reinforced resin material, a bolt embedded in the base material with a rope-shaped member in which the long fibers are woven in the axial direction of the bolt shaft portion, or a fiber reinforcement reinforced by embedding a reinforcing cloth in the base material. Although the nut made of a resin material has been described, the present invention is not limited to this and may have another structure. May be randomized, or in the case of reinforced cloth, it may be formed into a non-woven fabric by short fibers, and the woven fabric weave is plain weave, twill weave, satin It may be woven or the like. In short, any bolts or nuts made of a fiber reinforced resin material in which a fiber member made of fibers is embedded in a base material made of synthetic resin so as to increase the strength of the base material. May be.

In each of the above embodiments, the FRP
An example using an epoxy resin as a matrix and carbon fiber or glass fiber as a reinforcing fiber has been described.
The present invention is not limited to this, and may be composed of other matrix or reinforcing fiber. For example, an unsaturated polyester resin, a polyamide resin, or the like may be used as the matrix. As the reinforcing fibers, synthetic resin fibers such as aramid resin (aromatic polyamide resin) and polyvinyl alcohol, metals such as titanium (Ti), alumina (A)
l ₂ O ₃₎ metal oxide such as, ceramics containing nitride such as carbide or SiN such as SiC, long fibers consisting of boron (B) or the like, short fiber, to the like may be used whiskers, these lengths It may be a combination of fibers, short fibers, whiskers and the like. The blending amount of long fibers, short fibers, whiskers, etc. in the fiber-reinforced resin material according to the present invention is preferably selected from the numerical values of about 50 to 70% by volume.

Further, in each of the above-described embodiments, the facilities and members relating to the levitation railway are described as an example of the objects to be fastened or the objects to be fastened by the bolts and nuts, but the present invention is not limited to this. Without limitation, general facilities, vehicles,
It is widely applicable to the fastening of members or parts such as ships, aircraft, machines or instruments.

[0045]

As described above, according to the present invention,
Since the bolts and nuts are made of the fiber reinforced resin material in which the fiber member is embedded in the base material made of synthetic resin, the object to be fastened can be firmly fastened to the fastened object, and the magnetic field or temperature changes. It is possible to mitigate the fluctuation of the bolt axial force due to. It also has the advantages of non-magnetism, electrical insulation, corrosion resistance, and lightness.

[Brief description of drawings]

1A and 1B are diagrams showing a configuration of a bolt according to an embodiment of the present invention, FIG. 1A showing a partially cutaway side view of the bolt, and FIG. 1B showing FIG. 1A. FIG. 1 (C) is a partially cutaway front view of the head portion of the bolt, and FIG. 1 (C) is a conceptual diagram showing a method for producing the reinforced cloth shown in FIG. 1 (B).

2A and 2B are views showing an example of attaching a member using a bolt which is another embodiment of the present invention, FIG. 2A shows a state before attaching the member, and FIG. 2B shows after attaching the member. The respective states are shown.

FIG. 3 is a diagram showing measurement results of axial force, temperature, and time of a bolt in the member mounting example shown in FIG.

[Explanation of symbols]

 10,10A Bolt 11 Head 12 Shaft 13,13A Male screw 14,14A Column 15 Through hole 16 Fixing part 21 Matrix 22 Reinforcing fiber 23 Matrix 24 Reinforcing cloth 25 Reinforcing tape 26 Matrix 27 Reinforcing fiber 30 Nut 41 Floating Coil 42 Propulsion coil 43 Spacer 50 Load cell C Concrete wall

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location B29K 307: 04 309: 08 B29L 1:00 (72) Inventor Naoto Mifune Nikko Mitsumachi, Kokubunji, Tokyo 8-chome 38, Railway Technical Research Institute (72) Inventor Yoshihiro Sakamoto 1000, Kamoshida-cho, Aoba-ku, Yokohama-shi, Kanagawa Mitsubishi Chemical Corporation Yokohama Research Institute

Claims (9)

[Claims] 1. A nut formed of a first fiber-reinforced resin material in which a first fiber member is embedded in a first base material made of synthetic resin to increase the strength of the first base material. A bolt made of a fiber-reinforced resin material configured to fasten an object to be fastened to the object to be fastened by screwing and to mitigate a change in axial force due to a change in magnetic field or temperature, wherein the axis of the fiber-reinforced resin material bolt is The first fiber member in the section is a plurality of long fibers arranged along the axial direction of the fiber reinforced resin material bolt, wherein the fiber reinforced resin material bolt is provided. 2. A nut formed of a first fiber-reinforced resin material in which a first fiber member is embedded in a first base material made of synthetic resin to increase the strength of the first base material, A bolt made of a fiber-reinforced resin material configured to fasten an object to be fastened to the object to be fastened by screwing and to mitigate a change in axial force due to a change in magnetic field or temperature, wherein the axis of the fiber-reinforced resin material bolt is The first fiber member in the portion is a fiber reinforced structure in which a plurality of long fibers are knitted into a substantially rope shape and are arranged along the axial direction of the bolt made of the fiber reinforced resin material. Bolt made of resin material. 3. A nut formed of a first fiber-reinforced resin material in which a first fiber member is embedded in a first base material made of synthetic resin to increase the strength of the first base material. A bolt made of a fiber-reinforced resin material configured to fasten an object to be fastened to the object to be fastened by screwing and to mitigate a change in axial force due to a change in magnetic field or temperature, wherein the axis of the fiber-reinforced resin material bolt is A bolt made of a fiber-reinforced resin material, wherein the first fiber member in the part is a plurality of short fibers that are three-dimensionally dispersed and arranged. 4. The first fiber member in the head of the fiber-reinforced resin material bolt according to claim 1, wherein the first fiber member is formed by arranging long fibers in a strip shape. A fiber-reinforced resin material bolt, comprising a plurality of reinforced cloths, which are formed by weaving the reinforced tapes in a checkered pattern and are laminated and arranged in the axial direction of the fiber-reinforced resin material bolt. 5. The plurality of three-dimensionally distributed first fiber members in the head of the fiber-reinforced resin material bolt according to claim 1. Bolts made of fiber reinforced resin material, characterized by being short fibers of. 6. The fiber-reinforced resin material bolt according to claim 2, wherein the long fiber or the short fiber is carbon, glass, aramid resin,
A fiber-reinforced resin material bolt comprising a fiber made of any one of boron, titanium, alumina, and polyvinyl alcohol, or a combination of these fibers. 7. A bolt formed of a second fiber reinforced resin material in which a second fiber member is embedded in a second base material made of synthetic resin to increase the strength of the second base material, In a nut made of a fiber-reinforced resin material, which is configured to fasten an object to be fastened to a fastened object by screwing, and to alleviate a change in axial force of the bolt due to a change in magnetic field or temperature, The second fiber member in the nut is formed by braiding reinforcing tapes formed by arranging long fibers in a strip shape in a substantially checkered pattern and arranged in layers in the axial direction of the nut made of the fiber-reinforced resin material. A nut made of fiber reinforced resin material, which is a plurality of reinforced cloths. 8. A bolt formed of a second fiber-reinforced resin material, in which a second fiber member is embedded in a second base material made of synthetic resin to increase the strength of the second base material, In a nut made of a fiber-reinforced resin material, which is configured to fasten an object to be fastened to a fastened object by screwing, and to alleviate a change in axial force of the bolt due to a change in magnetic field or temperature, A nut made of a fiber-reinforced resin material, wherein the second fiber member in the nut is a plurality of short fibers that are three-dimensionally dispersed and arranged. 9. The nut made of a fiber-reinforced resin material according to claim 7 or 8, wherein the long fiber or the short fiber is
A nut made of a fiber-reinforced resin material comprising a fiber made of any one of carbon, glass, aramid resin, boron, titanium, alumina and polyvinyl alcohol, or a combination of these fibers.