JPH06300070A - Energy absorbing member - Google Patents

Abstract

PURPOSE:To provide an energy absorbing member which has excellent rigidity, excellent adhesiveness of resin and reinforcing fiber and which can absorb the energy efficiently and which can show the sufficiently high energy absorbing ability. CONSTITUTION:In an energy absorbing member 31 made of compound material, which is composed of resin and reinforcing fiber, the resin having 1-4 times the rupture ductility of the reinforcing fiber is used, and the reinforcing fiber having at least any characteristic among a rupture ductility of 1.5% or more, a tensile strength of 450kgf/mm<2> or more, a tensile elastic ratio of 23,000kgf/ mm<2> or more and a surface relief degree of 1.08 or more is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an energy absorbing member, and in particular, it is composed of a composite material of resin and reinforcing fibers,
The present invention relates to the structure of an impact energy absorbing member.

[0002]

2. Description of the Related Art For example, an energy absorbing member that absorbs impact energy is used around the seat of an aircraft, around the seat of an automobile, around a bumper, and various structural members (Japanese Patent Laid-Open No. 60-109630). 62-17
No. 438, etc.). In addition to the ability to absorb impact energy well, this energy absorbing member is generally lightweight,
Since high rigidity is required, a composite material of a resin and reinforcing fibers, so-called fiber reinforced plastic (hereinafter sometimes referred to as FRP), especially carbon fiber reinforced plastic (hereinafter also referred to as CFRP) There is) is said to be suitable.

[0003]

However, the conventional energy absorbing member made of a composite material of resin and reinforcing fibers has insufficient energy absorbing ability, rigidity, adhesiveness between resin and reinforcing fibers, and the like. However, the reality is that it has not been put to practical use.

An object of the present invention is to provide an energy absorbing member which is excellent in rigidity, adhesiveness between a resin and a reinforcing fiber, can efficiently absorb energy and can exhibit a sufficiently high energy absorbing ability.

[0005]

The energy absorbing member according to claim 1 of the present invention which meets this object is made of a composite material of resin and reinforcing fibers, and the breaking elongation of the resin is the breaking elongation of the reinforcing fibers. The breaking elongation of the reinforcing fiber is 1.5% or more.

The energy absorbing member according to claim 2 of the present invention is made of a composite material of resin and reinforcing fibers, and the breaking elongation of the resin is 1 to 4 times the breaking elongation of the reinforcing fibers. , The tensile strength of the reinforcing fiber is 450 kgf / mm
It is characterized by being ² or more.

The energy absorbing member according to claim 3 of the present invention is made of a composite material of resin and reinforcing fibers, and the breaking elongation of the resin is 1 to 4 times the breaking elongation of the reinforcing fibers. , The tensile elastic modulus of the reinforcing fiber is 23,000 kg
f / mm ² or more.

The energy absorbing member according to claim 4 of the present invention is made of a composite material of resin and reinforcing fibers, and the breaking elongation of the resin is 1 to 4 times the breaking elongation of the reinforcing fibers. The surface relief of the reinforcing fiber is 1.08 or more.

The energy absorbing member according to claim 5 of the present invention is made of a composite material of resin and reinforcing fibers, and the breaking elongation of the resin is 1 to 4 times the breaking elongation of the reinforcing fibers. The reinforcing fiber has a breaking elongation of 1.5% or more and a tensile strength of 450 kgf / mm ² or more.

The energy absorbing member according to claim 6 of the present invention is made of a composite material of resin and reinforcing fibers, and the breaking elongation of the resin is 1 to 4 times the breaking elongation of the reinforcing fibers. The reinforcing fiber has a breaking elongation of 1.5% or more and a tensile elastic modulus of 23,000 kgf / mm ² or more.

The energy absorbing member according to claim 7 of the present invention is made of a composite material of resin and reinforcing fibers, and the breaking elongation of the resin is 1 to 4 times the breaking elongation of the reinforcing fibers. The reinforcing fiber has a breaking elongation of 1.5% or more and a surface relief of 1.08 or more.

The energy absorbing member according to claim 8 of the present invention is made of a composite material of resin and reinforcing fibers, and the breaking elongation of the resin is 1 to 4 times the breaking elongation of the reinforcing fibers. The breaking elongation of the reinforcing fiber is 1.5% or more, the tensile strength is 450 kgf / mm ² or more, and the tensile elastic modulus is 23,
000 kgf / mm ² or more.

The energy absorbing member according to claim 9 of the present invention is made of a composite material of resin and reinforcing fibers, and the breaking elongation of the resin is 1 to 4 times the breaking elongation of the reinforcing fibers. The breaking elongation of the reinforcing fiber is 1.5% or more, the tensile strength is 450 kgf / mm ² or more, and the surface undulation is 1.0.
8 or more.

An energy absorbing member according to a tenth aspect of the present invention is made of a composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
And the breaking elongation of the reinforcing fiber is 1.5% or more, the tensile elastic modulus is 23,000 kgf / mm ² or more, and the surface undulation degree is 1.08 or more.

The energy absorbing member according to claim 11 of the present invention comprises a composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
The breaking elongation of the reinforcing fiber is 1.5% or more, the tensile strength is 450 kgf / mm ² or more, and the tensile elastic modulus is 2 times.
3,000kgf / mm ² or more, surface relief 1.08
It is characterized by the above.

An energy absorbing member according to a twelfth aspect of the present invention is made of a composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
And the tensile strength of the reinforcing fiber is 450 kgf / m.
m ² or more and the tensile elastic modulus is 23,000 kgf / mm ² or more.

An energy absorbing member according to claim 13 of the present invention is made of a composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
And the tensile strength of the reinforcing fiber is 450 kgf / m.
m ² or more, and the surface undulation degree is 1.08 or more.

An energy absorbing member according to a fourteenth aspect of the present invention is made of a composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
And the tensile strength of the reinforcing fiber is 450 kgf / m.
m ² or more, the tensile elastic modulus is 23,000 kgf / mm ² or more, and the surface undulation degree is 1.08 or more.

An energy absorbing member according to a fifteenth aspect of the present invention is made of a composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
And the tensile modulus of the reinforcing fiber is 23,000 k.
gf / mm ² or more, and the surface undulation degree is 1.08 or more.

In each of the above energy absorbing members, when the reinforcing fiber is made of carbon fiber, the amount of surface functional group (O), which is the atomic number ratio of oxygen (O) to carbon (C) on the surface of the reinforcing fiber. / C) is preferably 0.08 or more.
When the surface functional group amount (O / C) is 0.08 or more, the activated O enhances the adhesiveness of the reinforcing fiber surface,
Since the adhesive strength between the resin and the reinforcing fiber is increased, the composite material as a whole can exhibit extremely high rigidity and energy absorption capability. If the amount of surface functional groups (O / C) is less than 0.08, the adhesiveness between the resin and the reinforcing fiber becomes insufficient, and peeling or breakage easily occurs at the interface between the resin and the reinforcing fiber during energy absorption. , The energy absorption capacity is reduced accordingly.

In the above-mentioned carbon fiber reinforcing fiber, it is preferable that the crystal size is 20 Å or more. This crystal size particularly affects the tensile elastic modulus, and when the crystal size is 20 Å or more, a high tensile elastic modulus can be easily achieved. The higher the tensile modulus, the better the energy absorption capacity.

In each of the above energy absorbing members, the reinforcing fiber is not limited to carbon fiber, and as the reinforcing fiber other than carbon fiber, for example, glass fiber, aromatic polyamide fiber, alumina fiber, silicon carbide fiber and boron fiber can be used. You can choose from.

The energy absorbing member made of the above composite material will be described in more detail below.

The resin in the composite material constituting the energy absorbing member of the present invention has a breaking elongation of 1 to 4 times that of the reinforcing fiber. That is, the breaking elongation of the resin is relatively close to the breaking elongation of the reinforcing fiber. Since the breaking elongations of both are close to each other, when the energy is absorbed, it is possible to develop a state in which both of them are simultaneously broken or a broken state close to that, and the energy absorption member composed of the composite material can efficiently absorb energy. . If the difference in breaking elongation between the two is large, either one will break first,
When the destruction time is relatively early, it becomes difficult to achieve high energy absorption capacity.

In the present invention, by using a composite material of a resin having a breaking elongation as described above and a reinforcing fiber having a high breaking elongation, tensile strength and / or tensile modulus, excellent energy can be obtained. Absorbing ability can be demonstrated and high specific absorbed energy amount can be achieved. Further, by increasing the surface undulation degree of the reinforcing fiber, or when the reinforcing fiber is a carbon fiber, the amount of surface functional groups (O / C)
By increasing the value, the adhesiveness between the resin and the reinforcing fiber is enhanced, and a composite material that is unlikely to peel or break at the interface between the two can be realized, and an excellent energy absorption capacity can be achieved. That is, in the energy absorbing member of the present invention, a composite material in which a resin having a breaking elongation equal to or slightly higher than the breaking elongation of the reinforcing fiber and a reinforcing fiber having high strength or / and high adhesiveness are combined. By so doing, it is possible to efficiently exhibit an excellent energy absorption capacity and achieve a high specific absorbed energy amount.

The resin of the composite material in the present invention may be selected so that the relationship with the type of reinforcing fiber to be used, particularly the breaking elongation thereof, satisfies the above range. The resin used, depending on the reinforcing fiber used, for example, epoxy resin, unsaturated polyester resin, polyvinyl ester resin, phenol resin, guanamine resin, polyimide resin such as bismaleimide triazine resin, furan resin, Examples thereof include polyurethane resins, polydiallyl phthalate resins, and thermosetting resins such as amino resins such as melanin resins and urea resins. Also, nylon 6, nylon 66, nylon 11, nylon 610, nylon 6
Polyamides such as 12 or copolyamides of these polyamides, polyesters such as polyethylene terephthalate and polybutylene terephthalate, copolyesters of these polyesters, and further polycarbonates, polyamide imides, polyphenylene sulfides, polyphenylene oxides, polysulfones,
Polyether sulfone, polyether ether ketone,
Examples thereof include polyether imide and polyolefin, and thermoplastic elastomers typified by polyester elastomer and polyamide elastomer. Further, as the resin satisfying the above range, rubber such as acrylic rubber, acrylonitrile butadiene rubber, urethane rubber, silicone rubber, styrene butadiene rubber, fluororubber can be used. Furthermore, it is also possible to use a resin obtained by blending a plurality of the above-mentioned thermosetting resins and rubber.

In the present invention, the reinforcing fiber has a breaking elongation of 1.5% or more and a tensile strength of 450 kgf / mm ² or more,
It has any of the characteristics that the tensile elastic modulus is 23,000 kgf / mm ² or more and the surface undulation degree is 1.08 or more, or any combination of these characteristics.

When the breaking elongation of the reinforcing fiber is 1.5% or more, a large amount of energy can be absorbed by the energy absorbing member made of the composite material until the site where the breaking is expected to actually occur. become. If the breaking elongation is less than 1.5%, the reinforcing fiber is broken by a small amount of deformation of the energy absorbing member, and large energy cannot be absorbed when the reinforcing fiber is broken. Will be reduced.

The tensile strength of the reinforcing fiber is 450 kgf / mm
^When it is ² or more, the amount of energy required for breaking the fiber is large with respect to the impact energy applied to the energy absorbing member made of the composite material, so that a large amount of energy can be absorbed for the same amount of breaking. If the tensile strength is less than 450 kgf / mm ² , the reinforcing fibers are likely to break with a small amount of energy, and it becomes difficult to absorb a large amount of energy, and eventually the energy absorbing capacity of the energy absorbing member decreases. .

Reinforcing fiber has a tensile modulus of 23,000 kg
When it is f / mm ² or more, a high-rigidity energy absorbing member can be realized against impact energy applied to the energy absorbing member made of the composite material, and a large amount of energy can be absorbed. Moreover, buckling of the energy absorbing member is less likely to occur, and the length of one energy absorbing member can be increased. Tensile modulus of 23,000k
If it is less than gf / mm ² , the rigidity of the energy absorbing member is low, and it becomes difficult to absorb a large amount of energy, so that the energy absorbing capacity of the energy absorbing member is reduced.

When the surface roughness of the reinforcing fiber is 1.08 or more, the so-called anchor effect due to the surface undulation is improved, so that the adhesiveness between the reinforcing fiber and the resin is improved, and the interface that is extremely difficult to peel or break. Can be achieved. By improving the adhesiveness, the strength of the reinforcing fiber in the composite material can be utilized very effectively, and the rigidity of the composite material as a whole can be improved, so that a large amount of energy can be absorbed. If the surface undulation degree is less than 1.08, the anchor effect as described above cannot be expected, or even if there is little, it is difficult to improve the rigidity of the energy absorbing member, and eventually the energy absorbing ability of the energy absorbing member is improved. Becomes difficult.

As described above, in order to improve the adhesiveness between the reinforcing fiber and the resin, the surface functional group content (O / C) should be 0.08 or more when the reinforcing fiber is carbon fiber. It is valid. The characteristics of the surface functional group amount (O / C) of 0.08 or more are that the reinforcing fiber has a breaking elongation of 1.5% or more, a tensile strength of 450 kgf / mm ² or more, and a tensile elastic modulus of 23,000 kgf /. mm ² or more, surface undulation is 1.
It is preferable to have the characteristics of 08 or more.

Further, as described above, when the reinforcing fibers are carbon fibers, the crystal size is preferably 20 Å or more in order to easily achieve a high tensile modulus. Characteristics relating to the crystal size, the reinforcing fibers, the elongation at break of 1.5% or more, a tensile strength of 450 kgf / mm ² or more, a tensile modulus of 23,000kgf / mm ² or more, the surface undulations of 1.08 Above, furthermore, the amount of surface functional groups (O /
C) It is preferable to have the properties of 0.08 or more.

In the energy absorbing member of the present invention,
The reinforcing fibers in the composite material may be arranged in the range of 0 ° to ± 60 ° with respect to the axis of the energy absorbing member in the compression direction, except when a special combination arrangement is performed. If the angle is too large, the reinforcing fibers are not effectively used for absorbing the impact energy acting in the compression direction. Further, the form of the reinforcing fiber is not particularly limited, and a woven fabric of the reinforcing fiber can be used in addition to ordinary filaments.

The shape of the energy absorbing member made of the composite material of the present invention is not particularly limited, and various shapes such as a cylindrical shape, a columnar shape and a plate shape can be adopted. Typical shapes or applicable shapes are illustrated in FIGS. 1 to 10.

As a typical shape of the energy absorbing member, first, a cylindrical shape can be mentioned. The most typical shape as a cylindrical shape is a cylinder 1 as shown in FIG. The direction of the arrow in the figure is the compressive load acting direction as impact energy. Further, as shown in FIG. 2, a cylinder 2 in which the top of the cylinder is formed into a conical shape or a spherical shape can also be applied. Further, although not shown in the drawings, a prism, a cone, a pyramid, a truncated cone, a truncated pyramid, or a cylinder having an elliptical cross section, and further, as shown in FIG. A tubular shape 4 such as a tube) can also be adopted.

The shape is not limited to the cylindrical shape, but may be a columnar shape. For example, a columnar shape or a prismatic shape can be mentioned.

Further, it is possible to adopt a plate shape. For example, a corrugated plate-shaped member can be used as an energy absorbing member because it is strong against buckling. Also,
As shown in FIG. 4, for example, a cross section T having ribs 5
The shape 6 may be a V shape, or a shape 7 having a U-shaped cross section as shown in FIG. In the shape 7 having a U-shaped cross section shown in FIG. 5, the lid member 8 can be provided as shown by a two-dot chain line. Further, as shown in FIG. 6, a cross-shaped cross-section 9 may be used.

Furthermore, it is also possible to adopt a structure in which members of various shapes are combined. For example, FIGS.
As shown in FIG. 3, by inserting small elongated cylinders 12 and 13 into a large cylinder 10 and a large truncated cone 11 and composing these with a composite material, an energy absorbing member that is less likely to buckle can be obtained. .

Further, the energy absorbing member may be composed of one member, or may be composed of a plurality of members stacked or combined. For example, as shown in FIGS. 9 and 10, the energy absorbing members 16 and 17 may be configured by vertically stacking members 14, 15a, 15b and 15c made of a composite material having the same or similar shapes. . In the configuration of FIG. 10, each member may be alternately laminated inside and outside.

In the energy absorbing member as described above, it is desirable to form a trigger shape for sequentially destroying the energy absorbing member from the end, and this trigger is a pressing member for pressing the energy absorbing member. It may be provided on the side.

[Method of measuring characteristics and method of evaluating effects]
The method of measuring the characteristics and the method of evaluating the effects in the present invention will be described below. (1) Method of measuring tensile elongation at break of resin Measured according to ASTM-D-638.

(2) Elongation at Break, Tensile Strength, and Tensile Modulus of Fiber It was measured according to the resin-impregnated strand test method defined in JIS-R7601. The resin formulation and curing conditions used in the test are shown below. Resin Formulation: "Bakelite" ERL-4221 100 parts of 3 boron trifluoride monoethylamine (BF ₃ · MEA) ₃ parts acetone 4 parts Curing conditions: 130 ° C., 30 minutes

(3) Surface Roughness The composite material is cut perpendicular to the fiber direction, and the cut surface is mirror-polished by metal phase polishing. Here, the cross-sectional shape of the single fiber perpendicular to the polishing surface was measured by a scanning electron microscope (JSM manufactured by JSM Co., Ltd.).
-T300 type) is used to photograph a backscattered electron composition image at an accelerating voltage of 15 kV and a photographing magnification of 10,000 times on a film. The backscattered electron composition image photograph thus obtained was further stretched to 2 times at the time of printing, that is, the magnification was 2 in total.
It is taken as a photograph for surface undulation analysis with a magnification of 0000. Here, from the photograph for surface undulation analysis, the area S (m
m ² ) and the outer peripheral length L (mm) are measured. The surface undulation degree is obtained according to the following formula as a ratio of the above L and the outer peripheral length of a virtual perfect circle having the same S. Surface relief = L · (πS) ^−1/2 / 2 L is measured at 20000 times after accurately sticking non-stretchable cotton thread on the outer periphery of the single fiber cross-sectional image of the photograph, Can be removed and the length of the straight line can be measured. In addition, S was measured by placing a trace paper whose weight per unit area is known on a photograph printed at 20000 times, accurately tracing the outer periphery of the single fiber cross-sectional image, and accurately cutting the trace line. The weight can be converted from the weight of the cut single fiber cross-sectional image and the weight per unit area of the trace paper. The measurement is carried out on 10 monofilaments, and the average value is taken as the surface relief. There is no limitation on the method for measuring L and S as long as it can be accurately measured, and an image analyzer can be used in addition to the above method.

(4) Amount of surface functional group (O / C) It was determined by the following procedure by X-ray photoelectron spectroscopy. First, carbon fiber (bundle) from which sizing agents have been removed with a solvent
After cutting and arranging them on a copper sample support, the photoelectron escape angle was set to 90 °, and MgKα1, X-ray source was used.
2 is used and the sample chamber is kept at 1 × 10 ⁻⁸ Torr. The kinetic energy value (KE) of the main peak of C _1S is set to 969 eV as a correction of the peak associated with charging during measurement. The C _1S peak area was calculated as K. E. As 958-97
It is obtained by drawing a linear baseline in the range of 2 eV. The O _1S peak area was measured by K.K. E. As 714-726
It is determined by drawing a straight baseline in the range of eV. Here, the amount of surface functional groups (O / C) is calculated as an atomic number ratio from the ratio of the O _1S peak area and the C _1S peak area using a sensitivity correction value specific to the apparatus. The inventors of the present invention used a model ESCA-75 manufactured by Shimadzu Corporation.
0 was used to measure the ratio of the O _1S peak area to the C _1S peak area, and the ratio was divided by the sensitivity correction value of 2.85 to obtain the surface functional group amount (O / C).

(5) Crystal Size (Lc) The crystal size Lc is a value obtained by wide-angle X-ray diffraction according to the following procedure. That is, as the X-ray source, Cu Kα rays monochromated by the Ni filter are used, and 2θ = 2
The half width of the peak of the plane index (002) observed around 6.0 ° is scanned in the equatorial direction to find the half-value width, and the value calculated by the following formula is defined as the crystal size Lc. Lc = λ / (β ₀ cos θ) Here, λ: wavelength of X-ray (1.5418 angstrom in this case), θ: diffraction angle, β ₀ : true half width.
Note that β ₀ uses a value calculated by the following equation. ^{_{β 0 = (β A 2 -β}} 1 2) 1/2 where, β _A ^2: Apparent half width, beta ₁ ^2: apparatus constant (output Rigaku Denki Co. 4036A2 type X-ray generator 35
1.05 × 10 ^-2 ra when used at kV, 15 mA
d).

(6) Specific absorbed energy amount There is no standard or standardized method. As shown in FIG. 11, when a compressive load P is applied to the energy absorbing member 21 via the pressing member 22 to destroy the member 21, generally a load-displacement (displacement of the pressing member) diagram as shown in FIG. Is obtained. In this load-displacement diagram, displacements x ₁ to x ₂
The energy absorbed during is calculated as the area of the shaded area in the figure. The weight of the energy absorbing member destroyed during that period is calculated (if the members have the same cross section, the cross sectional area and (x
₂ −x ₁ ) and specific gravity)), and the value obtained by dividing the absorbed energy amount by the weight is taken as the specific absorbed energy amount. x ₁ , x
The setting of ₂ , the speed of displacement of the pressing member, and the like can be set appropriately.

[0048]

【Example】

Example 1 Carbon fiber T300 manufactured by Toray Industries, Inc. (breaking elongation: 1.5%,
Tensile elastic modulus: 23,500 kgf / mm ² ) is used as a reinforcing fiber, and an epoxy resin is used as a matrix (elongation at break 2.6%).
Using, a cylinder having an inner diameter of 70 mm, a wall thickness of about 3.0 mm, and a fiber orientation angle of ± 14 ° (angle with respect to the cylinder axis) was molded by the filament winding method.

The cylindrical composite material thus obtained was machined to an inner diameter of 70 m as shown in FIG.
m, a wall thickness of about 3.0 mm, a fiber orientation angle of ± 14 °, a length l of 70 mm, and an inclination angle θ of the upper end of 45 degrees, an energy absorbing member 31 made of a cylindrical composite material was obtained.

The energy absorbing member 31 is mounted on the universal testing machine 32 as shown in FIG. 14, and a compressive load is applied to the energy absorbing member 31 from the cross head 33 via the load cell 34 and the pressing member 35 to cross. Head 33
The load-displacement characteristics were measured with the displacement of No. 3 as the displacement of the pressing member 35. The displacement speed was 10 mm / min. As a result, a load-displacement diagram as shown in FIG.
The specific absorbed energy amount was 59 kJ / kg during 40 mm.

[0051]

As described above, according to the energy absorbing member of the present invention, the energy absorbing member is made of a composite material of resin and reinforcing fiber, and the breaking elongation of the resin is the breaking elongation of the reinforcing fiber. 1 to 4 times, and at least one of the breaking elongation, the tensile strength, the tensile elastic modulus, and the surface undulation of the reinforcing fiber is set to a specific value or more,
It is possible to realize an energy absorbing member that can efficiently absorb energy and that has a high energy absorbing capacity.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of the shape of an energy absorbing member of the present invention.

FIG. 2 is a perspective view showing another example of the shape of the energy absorbing member of the present invention.

FIG. 3 is a perspective view showing still another example of the shape of the energy absorbing member of the present invention.

FIG. 4 is a perspective view showing still another example of the shape of the energy absorbing member of the present invention.

FIG. 5 is a perspective view showing still another example of the shape of the energy absorbing member of the present invention.

FIG. 6 is a perspective view showing still another example of the shape of the energy absorbing member of the present invention.

FIG. 7 is a perspective view showing another structural example of the energy absorbing member of the present invention.

FIG. 8 is a perspective view showing still another structural example of the energy absorbing member of the present invention.

FIG. 9 is a vertical sectional view showing still another structural example of the energy absorbing member of the present invention.

FIG. 10 is a vertical sectional view showing still another structural example of the energy absorbing member of the present invention.

FIG. 11 is an exploded perspective view showing a method for measuring a specific absorbed energy amount.

FIG. 12 is a load-displacement diagram in the measurement of the amount of specific absorbed energy.

FIG. 13 is a perspective view of an energy absorbing member according to the first embodiment.

FIG. 14 is a partial front view of a universal testing machine showing measurement of load-displacement characteristics in Example 1.

15 is a load-displacement diagram in Example 1. FIG.

[Explanation of symbols]

1, 2 Cylindrical energy absorbing member 3 Flange portion 4 Cylindrical energy absorbing member having a flange portion 5 Rib 6 Energy absorbing member having T-shaped cross section 7 Energy absorbing member having U-shaped cross section 8 Lid member 9 Cross section Cross-shaped energy absorption member 10 Cylindrical energy absorption member 11 Frustum-shaped energy absorption member 12, 13 Elongated members 14, 15a, 15b, 15c Energy absorption member members 16, 17 Energy absorption of combined configuration Member 21 Energy absorbing member 22 Pressing member 31 Energy absorbing member 32 Universal testing machine 33 Crosshead 34 Load cell 35 Pressing member

Claims (17)

[Claims] 1. A composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
2. The energy absorbing member, wherein the breaking elongation of the reinforcing fiber is 1.5% or more. 2. A composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
And the tensile strength of the reinforcing fiber is 450 kgf / m.
An energy absorbing member having a size of at least m ² . 3. A composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
And the tensile modulus of the reinforcing fiber is 23,000 k.
An energy absorbing member having a gf / mm ² or more. 4. A composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
2. The energy absorbing member, wherein the reinforcing fiber has a surface undulation degree of 1.08 or more. 5. A composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
^{2. The} energy absorbing member, wherein the reinforcing fiber has a breaking elongation of 1.5% or more and a tensile strength of 450 kgf / mm ² or more. 6. A composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
^{2. The} energy absorbing member, wherein the reinforcing fiber has a breaking elongation of 1.5% or more and a tensile elastic modulus of 23,000 kgf / mm ² or more. 7. A composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
2. The energy absorbing member, wherein the breaking elongation of the reinforcing fiber is 1.5% or more and the surface undulation degree is 1.08 or more. 8. A composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
The breaking elongation of the reinforcing fiber is 1.5% or more, the tensile strength is 450 kgf / mm ² or more, and the tensile elastic modulus is 2 times.
An energy absorbing member having a weight of 3,000 kgf / mm ² or more. 9. A composite material of resin and reinforcing fibers,
The breaking elongation of the resin is 1 to 4 of the breaking elongation of the reinforcing fiber.
The breaking elongation of the reinforcing fiber is 1.5% or more, the tensile strength is 450 kgf / mm ² or more, and the surface undulation is 1.
Energy absorption member characterized by being 08 or more. 10. A composite material of resin and reinforcing fibers, wherein the breaking elongation of the resin is 1 of the breaking elongation of the reinforcing fibers.
To 4 times, the breaking elongation of the reinforcing fiber is 1.5% or more, the tensile elastic modulus is 23,000 kgf / mm ² or more, and the surface undulation degree is 1.08 or more. . 11. A composite material comprising a resin and a reinforcing fiber, wherein the breaking elongation of the resin is 1 of the breaking elongation of the reinforcing fiber.
A to 4 times, the elongation at break of the reinforcing fibers of 1.5% or more, a tensile strength of 450 kgf / mm ² or more, a tensile modulus of 23,000kgf / mm ² or more, the surface inequalities is 1.
Energy absorption member characterized by being 08 or more. 12. A composite material comprising a resin and a reinforcing fiber, wherein the breaking elongation of the resin is 1 of the breaking elongation of the reinforcing fiber.
~ 4 times, the tensile strength of the reinforcing fiber is 450kgf
/ Mm ² or more, tensile modulus of 23,000 kgf / mm
An energy absorbing member characterized by being ² or more. 13. A composite material comprising a resin and reinforcing fibers, wherein the breaking elongation of the resin is 1 of the breaking elongation of the reinforcing fibers.
~ 4 times, the tensile strength of the reinforcing fiber is 450kgf
/ Mm ² or more, the surface relief is 1.08 or more, the energy absorbing member. 14. A composite material comprising a resin and reinforcing fibers, wherein the breaking elongation of the resin is one of the breaking elongations of the reinforcing fibers.
~ 4 times, the tensile strength of the reinforcing fiber is 450kgf
/ Mm ² or more, tensile modulus of 23,000 kgf / mm
^2. An energy absorbing member having a surface undulation degree of ² or more and 1.08 or more. 15. A composite material of resin and reinforcing fibers, wherein the breaking elongation of the resin is 1 of the breaking elongation of the reinforcing fibers.
Is 4 times, and the tensile elastic modulus of the reinforcing fiber is 23,000.
An energy absorbing member characterized by having a surface undulation degree of 0 kgf / mm ² or more and 1.08 or more. 16. The surface functional group amount (O / C) of the reinforcing fiber, which is the atomic number ratio of oxygen (O) and carbon (C) on the surface.
Is a carbon fiber of 0.08 or more.
The energy absorbing member according to any one of 1. 17. The reinforcing fiber has a crystal size of 20Å.
The energy absorbing member according to any one of claims 1 to 16, which is the above carbon fiber.