JPH08170674A - Energy absorber provided with local reinforcing jig - Google Patents

Abstract

PURPOSE: To improve energy absorbing efficiency by increasing an average load without so changing a maximum load in collision, while an energy absorbing amount in collision is increased by stably collapsing a circular pipe with bucking destruction prevented. CONSTITUTION: An internal reinforcing jig 1 and/or an external reinforcing jig 2, fitted by suitable pressing force into an inner hole 4 and/or a periphery 5 of an FRP cylinder 3, are provided. Thus by preventing hollowed deformation and lengthwise crack of the cylinder when applied a collision load to act, deformation of a collapsing load is generated. In the vicinity of an end part in a collapse starting side of the FRP cylinder 3, by adjusting dimension, structure and a mounting position of the internal reinforcing jig and/or the external reinforcing jig set up in the inner hole and/or the periphery, a limit angle is congtrolled, and diagonally colliding energy can be stably absorbed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an energy absorber arranged at a portion of a vehicle or the like which receives an impact force, and in particular, even if it is a hollow cylinder having a wall thickness / diameter ratio in a buckling failure mode, it is crushed. The present invention relates to an energy absorber including a local reinforcing jig capable of absorbing energy depending on modes.

[0002]

2. Description of the Related Art For example, a vehicle such as an automobile is provided with an energy absorber for absorbing collision energy at the time of collision. This energy absorber is
As shown in FIG. 8, it is composed of a hollow cylindrical body having a tapered portion 10 at its tip and is mainly composed of a fiber reinforced composite material.
Hereinafter, this energy absorber will be referred to as FRP cylinder 3.

As shown in FIG. 29, the FRP cylinder 3 described above is used.
When a load 11 is applied to the slab due to a collision or the like, a compression fracture (hereinafter referred to as a crush) accompanied by the fragment 6 as shown in the figure occurs, and a large amount of energy can be absorbed. FIG. 30 is a diagram showing energy absorption in crushing. For example, “En
ergy Absorption in Compos
ite Tubes, J.M. Comp. Mat. Vol.
16, (Nov. 1982), P521 ". That is, in FIG. 30, when the horizontal axis is the displacement and the vertical axis is the load, the energy absorption amount E is represented by the area surrounded by a curve that initially sharply rises and then gradually changes.

On the other hand, as a known technique regarding the energy absorber, there is one disclosed in Japanese Patent Laid-Open No. 5-118370. This energy absorbing structure is composed of a fiber-reinforced thermoplastic resin hollow body having fibers inclined at an angle of 0 to 45 degrees with respect to the axis, and both or one of the tips is chamfered obliquely. With this, the collision energy or the compression energy at the time of collision is sufficiently absorbed.

[0005]

[Problems to be Solved by the Invention] As shown in FIG.
If the horizontal axis is 2t / D (t is the wall thickness, D is the outer diameter) and the vertical axis is the specific energy absorption amount [KJ / kg] of the energy absorption amount per unit weight, as shown in the figure, In the 2 t / D FRP cylinder 3 smaller than the critical dimension of D, the buckling failure mode is set instead of the crushing mode, and the energy absorption amount becomes an extremely small value and does not function as an energy absorber. That is, as shown in FIG. 32, in the buckling failure mode, when a load is applied to the FRP cylinder 3, dent deformation 12 occurs and the shape of the cylinder collapses, and as shown in FIG. 33, large vertical cracks in the vertical direction occur. 13 occurs and the whole buckles. However, in order to reduce the weight of the FRP cylinder 3, it is necessary to use one having a small 2t / D.

On the other hand, in the load-displacement diagram shown in FIG. 34, if the maximum load applied to the FRP cylinder 3 is Pmax and the average load is Pmean, the energy absorption efficiency is displayed as Pmean / Pmax. As will be described later in detail, in the case of the conventional FRP cylinder 3, this energy absorption efficiency shows a low value of around 70 [%]. To increase this value and increase the energy absorption efficiency, the average load Pme
It is necessary to increase the value of an.

Further, in recent years, oblique collisions of vehicles have frequently occurred, and energy absorption during oblique collisions is also a problem. Generally, when the energy absorber cylinder is compressed by a collision force P from an oblique direction of an angle α from the center axis of the cylinder as shown in FIG. 35, if α exceeds a certain angle (hereinafter, referred to as a limit angle), the fracture occurs. The mode is changed and the cylinder is not crushed. As shown in FIG. 35, a depression 12a is formed in the compression portion and a bulge 12b is formed in the vicinity thereof, the shape of the cylinder is broken, and a large vertical crack in the vertical direction is generated as shown in FIG. 13 is generated and destroyed and cannot absorb energy. Therefore, in order to increase the energy absorption capability at an oblique angle so that the FRP cylinder can also be used in an oblique collision, it is necessary to control the limit angle of the FRP cylinder, and thus the destruction mode.

The energy absorption structure shown in the above-mentioned Japanese Patent Laid-Open No. 5-118370 shows that the energy absorption amount is higher than that of the general conventional FRP cylinder 3. However, there is no research related to the above-mentioned value of 2t / D in this publication, and there is a problem that the buckling failure mode is caused depending on the value of 2t / D in the case of this technique. Furthermore, there is no research in this publication on energy absorption efficiency and diagonal collisions.

The present invention was devised in view of the above circumstances, and an object thereof is to provide an energy absorber provided with a local reinforcing jig for stably crushing an FRP cylinder to increase the amount of energy absorption. In addition, an energy absorber provided with a local reinforcing jig that increases the average load at the time of deformation without changing the maximum load at the time of collision and improves the energy absorption efficiency is provided. An object of the present invention is to provide an energy absorber provided with a local reinforcing jig that stably crushes and increases the amount of energy absorption.

[0010]

In order to achieve the above-mentioned object, the present invention is a hollow cylindrical energy absorber that absorbs energy at the time of collision, and has an appropriate inner hole and / or outer periphery. The energy absorber is provided with a local reinforcing jig provided with an internal reinforcing jig and / or an external reinforcing jig fitted by a pressing force. In addition, a plurality of the internal reinforcing jigs and / or the external reinforcing jigs are arranged along the axial direction of the energy absorber, and the internal reinforcing jigs and / or the external reinforcing jigs are provided in the energy absorber. It is arranged in the inner hole and / or the outer periphery in the vicinity of the end on the crushing start side, and the dimensions of the internal reinforcing jig and / or the external reinforcing jig,
The structure and arrangement position are determined in relation to the limit angle at which crushing occurs at an oblique collision, and the internal reinforcing jig and / or the external reinforcing jig are moved in the crushing progressing direction as the crushing of the energy absorber progresses. Or fixing the end portion of the energy absorber on the side opposite to the crushing start side to the mounting member by the external reinforcing jig, using the internal reinforcing jig as a stop ring, or tubing the external reinforcing jig. It is used as a band.

[0011]

[Function] By providing an internal reinforcing jig and / or an external reinforcing jig on the inner hole and / or the outer peripheral part of the thinned FRP cylinder,
Reinforce the RP cylinder. Therefore, even if impact energy is applied, the occurrence of the above-mentioned dent deformation and vertical cracks can be prevented by the restraining force of the internal and / or external reinforcing jigs.
This allows the FRP cylinder to stably absorb energy. By appropriately setting the arrangement and the number of the internal reinforcing jig and the external reinforcing jig, it is possible to generate only the crushing mode even in the FRP cylinder having the above-mentioned critical dimension or less. Further, by mounting the internal and / or external reinforcing jigs on the inner hole and / or the outer periphery in the vicinity of the end on the crushing start side, it becomes possible to increase the average load without changing the maximum load at the time of collision,
The energy absorption efficiency can be greatly improved. At the same time, it is possible to control so as to increase the limit angle that causes crushing even in an oblique collision, and it is possible to stably absorb energy. Further, the internal reinforcing jig and / or the external reinforcing jig moves in the crushing direction as the crushing progresses, whereby the pre-crushing portion of the FRP cylinder is sequentially reinforced and the crushing mode is maintained. Further, the end portion of the energy absorber opposite to the crush start side is fixed to a mounting member by using an external reinforcing jig, and in an oblique collision, the energy absorber is divided by the component force in the direction perpendicular to the axis of the energy absorber. Prevents falling off the mounting surface. Furthermore, by using a stop ring as the internal reinforcing jig and using a tubing band as the external reinforcing jig, the energy absorber of the present invention can be implemented easily and inexpensively.

[0012]

【Example】

(Embodiment 1) Embodiment 1 of the present invention is shown in FIGS. 1 is a sectional view taken along the line BB of FIG. 2, and FIG. 2 is a line A of FIG.
It is -A sectional drawing. As shown in FIGS. 1 and 2, in the present embodiment, the internal reinforcing jig 1 is fitted into the inner hole 4 of the FRP cylinder 3 substantially in the middle in the axial direction, and faces the internal reinforcing jig 1 on the outer periphery 5. The external reinforcing jig 2 is provided at the position. Figure 2
As shown in FIG. 2, the inner reinforcing jig 1 and the outer reinforcing jig 2 are, for example, expander-shaped ring-shaped members with a part thereof cut away, and have a substantially uniform inner pressure over the entire circumference of the inner hole 4 and the outer circumference 5. It acts on the FRP cylinder 3 so as to apply external pressure. As described above, the intermediate portion of the FRP cylinder 3 is locally reinforced by the internal reinforcing jig 1 and the external reinforcing jig 2 to restrain the deformation. FIG. 3 shows the FRP cylinder 3 of this embodiment.
The crushed state of is shown. Due to the action of the collision load, a fragment 6 is generated at the end portion of the FRP cylinder 3 as shown in the drawing, but the dent deformation 12 and the vertical crack 13 as shown in FIGS. 32 and 33 are caused by the internal reinforcing jig 1 and the external reinforcing jig. It is prevented by the presence of 2 and only crushing by debris 6 occurs as shown. This is because deformation and buckling of the FRP cylinder 3 are suppressed by the action of the restraining forces 7 and 8 of the inner reinforcing jig 1 and the outer reinforcing jig 2 as shown in FIG. As described above, even the FRP cylinder 3 having a small 2t / D can be deformed in the crushing mode without causing the buckling failure mode and can sufficiently absorb the collision energy.

(Embodiment 2) In this embodiment, as shown in FIGS. 5 and 6, the internal reinforcing jigs 1, 1 and the outside are provided on the inner hole 4 and the outer periphery 5 near the upper and lower ends of the FRP cylinder 3. The reinforcing jigs 2 and 2 are provided. As shown in FIG. 6, the respective restraining forces 7, 7 and 8, 8 keep the FRP cylinder 3 in a circular cross section and prevent buckling failure. The internal reinforcing jig 1 and the external reinforcing jig 2 on the upper side of the drawing gradually move downward due to the occurrence of the crushing, and the crushing of the FRP cylinder together with the internal reinforcing jig 1 and the external reinforcing jig 2 on the lower side. It functions as a reinforcing member for the front part.

(Embodiment 3) In this embodiment, as shown in FIG. 7 and FIG. 8, a plurality of (3 in the figure) internal reinforcing members are provided along the axial direction only in the inner hole 4 of the FRP cylinder 3. Tools 1, 1,
1 is provided. By appropriately setting the restraining force 7 of the internal reinforcing jig 1, the deformation of the FRP cylinder 3 is prevented without using the external reinforcing jig 2, and the buckling failure mode does not occur. Also in this embodiment, the internal reinforcing jig 1 on the upper side gradually moves downward as the crush occurs and functions as a reinforcing member.

(Embodiment 4) This embodiment is based on FIG. 9 and FIG.
As shown in FIG. 3, a plurality of (two in the figure) internal reinforcing jigs 1 and 1 are provided centrally in the middle portion of the inner hole 4 of the FRP cylinder 3. As shown in FIG. 10, the buckling failure is effectively prevented by the internal restraining forces 7, 7 concentratedly acting on the intermediate portion where the deformation is large.

FIG. 11 shows load-displacement curves of the FRP cylinder 3 reinforced as in Examples 1 to 4 and the conventional FRP cylinder 3 without reinforcement. In this case, the conventional F
The value of 2t / D of the RP cylinder 3 indicates the buckling failure mode as will be described later in the comparison (1) of the energy absorption characteristics of FIG. 37. After the displacement point F shown in the curve C of FIG. Buckling damage and extremely low energy absorption. on the other hand,
The curve D is the curve of the present embodiment, and it can be seen that there is no abrupt load change even after passing the displacement point F, and it is stably crushed. From the above, it can be seen that even a thin FRP cylinder 3 having a small value of 2t / D can sufficiently function as an energy absorber.

Comparison of energy absorption characteristics of FIG. 37 (1)
6 shows the energy absorption characteristics of the FRP cylinder 3 of Examples 1 to 4 and the conventional FRP cylinder 3 without reinforcement. The FRP cylinder 3 used has an inner diameter of 40 [mm], a wall thickness of 0.8 [mm], and a length of 50 [mm], and is 2 t /
D = 0.038, which is close to the critical dimension 2t / D = 0.04. Further, the material is made of epoxy resin containing fibers as shown in the table, and is manufactured by the sheet winding method. As the energy absorption characteristic value, a destruction mode, absorbed energy [kgf · m] at a displacement of 30 [mm], and maximum load [kgf] are shown. The conventional FRP cylinder 3 is broken in the buckling mode if no reinforcing jig is provided in this case. However, since the reinforcing jig is provided in this embodiment, the FRP cylinder 3 is in the crushing mode in all cases. Destruction has been realized. Also,
The maximum load value of the present embodiment has an increase rate of -3.3 [%] to 30.7 [%] as compared with the conventional load, and does not change much. On the other hand, the rate of increase in the value of absorbed energy is 638 [%] to 994 [%], which is a remarkable increase. From the above, it is demonstrated that the FRP cylinder 3 of this embodiment has an extremely large energy absorption characteristic.

(Embodiment 5) This embodiment is claim 3 of the present invention.
This is an embodiment corresponding to the FRP, and as shown in FIG.
An external reinforcing jig 2a is attached to the outer periphery 5a near the end of the cylinder 3 on the crushing start side. Specifically, the FRP cylinder 3 is attached at a position avoiding the tapered portion 10. By attaching this external reinforcing jig 2a, the outer periphery 5a is not
The restraining force 8a as shown in FIG. Its binding force 8a
Serves to locally reinforce and restrain the crushed portion of the FRP cylinder 3 locally, and acts as a force to prevent the crack 14 that delaminates the FRP cylinder 3 shown in FIG. 14 from propagating as the crushing progresses. As a result, the energy absorption amount of the FRP cylinder 3 is increased. In addition, as described above, the tapered portion 10
Since the external reinforcing jig 2a is placed at a position avoiding
The maximum load at the time of collision is almost the same as the conventional load. In this embodiment, as the external reinforcing jig 2a, for example, as shown in FIG.
A known tubing band 2b as shown in 0 was used. The tubing band 2b is characterized in that it applies a uniform restraining force 8a to the outer periphery 5a as shown in FIG. 13 and is movable along the axial direction. Also,
The restraining force 8a of the tubing band 2b can be freely changed by tightening the screw 9.

(Embodiment 6) This embodiment is based on FIG. 15 and FIG.
As shown in FIG. 6, an internal reinforcing jig 1a and an external reinforcing jig 2a are provided in the inner hole 4a and the outer periphery 5a near the end of the FRP cylinder 3 on the side where the crush is started. Specifically, an internal reinforcing jig 1a and an external reinforcing jig 2a are provided at positions where the taper portion 10 of the FRP cylinder 3 is removed. For example, a known stop ring 1b as shown in FIG. And the tubing band 2b is adopted. These are characterized in that a uniform pressing force is applied to the inner hole 4a and the outer circumference 5a, and that they can be moved along the axial direction. A stop ring 1b having an appropriate outer diameter with respect to the inner diameter of the FRP cylinder 3.
Is used, a uniform and sufficient restraining force 7a (see FIG.
6) can be added. In the tubing band 2b, the restraining force 8a can be freely changed by tightening the screw 9 as described above. More binding force 7
As shown in FIG. 16, the FRP cylinder 3 is reinforced by a and 8a so that the local deformation is restrained, and the internal reinforcing jig 1a and the external reinforcing jig 2a are arranged at the position avoiding the tapered portion 10. The maximum load at the time of collision is almost the same as the conventional load.

(Embodiment 7) In this embodiment, as shown in FIG. 17, an inner reinforcing jig 1a is inserted in the inner hole 4a instead of the outer reinforcing jig 2a in the fifth embodiment. It is also possible to restrain the deformation of the local area. FIG.
Shows the action of the restraining force 7a in this embodiment.

FIG. 19 schematically shows the relationship between the load P acting on the FRP cylinder 3 and the restraining forces 7a and 8a in FIG. F due to the action of restraining force 7a, 8a
A frictional force f acts on the inner hole 4 and the outer periphery 5 of the RP cylinder 3 along the axial direction. This frictional force f resists the load P.
Therefore, by setting the restraining forces 7a and 8a so that the value of the frictional force f is slightly lower than the load P, the load P
Internal reinforcing jig 1a and external reinforcing jig 2a
Moves downward. As a result, the portions of the FRP cylinder before being crushed are sequentially reinforced and the crushing mode can be maintained.

FIG. 21 shows load-displacement curves of the FRP cylinder 3 of Examples 5 to 7 and the conventional FRP cylinder 3. It is the FRP cylinder 3 of Examples 5 to 7 and the conventional FRP cylinder 3 in the range where the value of 2t / D is larger than the critical dimension, as will be described later in comparison (2) of the energy absorption characteristics of FIG.
And shows the comparison of the energy absorption amount. As shown in the figure, in the case of the FRP cylinder 3 of this embodiment, the average load at the same displacement point is high and the energy absorption amount is large.

Comparison of energy absorption characteristics of FIG. 38 (2)
6 is a comparison of the energy absorption characteristics of the FRP cylinder 3 provided with the external reinforcing jig 2a shown in Example 5 (FIG. 12) and the conventional FRP cylinder 3 not provided with the same. The FRP cylinder 3 used has an inner diameter of 40 [mm], a wall thickness of 1.6 [mm], and a length of 200 [mm], and is 2 t / D.
The limit dimension is exceeded at 0.07. As the energy absorption characteristic value, the energy absorption amount (kgf · m) at displacements 30 [mm] and 50 [mm] and the average load [kg]
f], energy absorption efficiency [%] and maximum load [kg]
f] is raised. A satin woven fabric is used as the fiber, and an epoxy resin is used as the resin. It is also manufactured by the sheet winding method. As can be seen from the comparison (2) of the energy absorption characteristics of FIG. 38, the increase rate of the maximum load is −0.39 [%],
There is almost no difference. However, the rate of increase of the other characteristics is as large as about 15 [%] to 21 [%]. In addition, Example 6
38 and 7, almost the same results as the energy absorption characteristics shown in the comparison (2) of the energy absorption characteristics of FIG. 38 are required.

(Embodiment 8) This embodiment is an embodiment in which an oblique collision can be effectively dealt with. As shown in FIGS. 22 and 23, the end portion during the crushing is inclined. And the outer circumference 5 near the lower end of the inclined crushed portion of the FRP cylinder 3.
While operating so that the external reinforcing jig 2c is located at b,
The fixing jig 15 and the external reinforcing jig 2 are attached to the lower end of the FRP cylinder 3.
d is attached. By attaching the external reinforcing jig 2c, a binding force 8 as shown in FIG.
b acts. Due to the restraining force 8b, even if the compressive force P of the oblique collision angle α exceeding the limit angle is added, the FRP cylinder 3
Has a circular cross section, and has a recess 12a, a bulge 12b and a vertical crack 13 as shown in FIGS.
Is prevented and is stably crushed to absorb energy stably. The fixing jig 15 is a mounting member for attaching the FRP cylinder 3 to a vehicle body or the like, and includes a flat plate-like portion 16 that abuts on the lower end of the FRP cylinder 3 and an inner hole that projects from the flat-plate-like portion 16 and is near the lower end of the FRP cylinder 3. 4c. The external reinforcing jig 2d includes the protrusion 1
The outer periphery 5c near the lower end of the FRP cylinder 3 fitted with 7 is firmly tightened. As a result, a restraining force 8c as shown in FIG. 24 acts on the outer circumference 5c. By the binding force 8c,
The inner wall near the lower end of the FRP cylinder 3 is brought into close contact with the protrusion 17. As a result, when the diagonal compression force P is received, the FRP
The cylinder 3 is prevented from falling down, and the lower portion of the FRP cylinder 3 is reinforced. In this embodiment, the same external reinforcement jig 2d as the external reinforcement jig 2c is used.

FIG. 25 shows load-displacement curves of the reinforced FRP cylinder 3 and the non-reinforced FRP cylinder 3 of this embodiment. In this case, the FRP cylinder 3 without reinforcement does not undergo a sudden load change when the inclination angle of the oblique compression force is 5 degrees and is stably crushed, but when it is 10 degrees, it cannot absorb energy and is displaced in the axial direction. Buckles and breaks before it progresses sufficiently. From this, it can be seen that the limit angle of the FRP cylinder 3 without reinforcement is between 5 and 10 degrees. On the other hand, in the reinforced FRP cylinder 3 of this embodiment, the inclination angle of the oblique compression force is 1
At 5 degrees, there is no sudden change in load and it is crushed stably, but at 20 degrees, it showed a behavior similar to that of the FRP cylinder 3 of 10 degrees without reinforcement (not shown, but see FIG. 39). ). From this, it can be seen that the limit angle of the reinforced FRP cylinder 3 of this example is between 15 and 20 degrees. That is, it can be seen that the reinforcement increased the limit angle from between 5 and 10 degrees to between 15 and 20 degrees, that is, the limit angle was increased by about 10 degrees. From the above,
It is understood that the limit angle and the fracture mode can be controlled depending on the structure of the local reinforcement of the FRP cylinder 3, and the oblique energy absorption characteristics of the cylinder can be improved.

Comparison of energy absorption characteristics of FIG. 39 (3)
22 is a comparison of the energy absorption characteristics of the FRP cylinder 3 provided with the external reinforcing jig 2c shown in Example 8 (FIG. 22) and the FRP cylinder 3 not provided with it. From the table,
If the angle exceeds the limit angle, the energy and maximum load will decrease with the same tendency even if the local part is reinforced, but the limit angle is about 1
It can be seen that the energy can be stably absorbed by increasing the temperature by 0 degree (see also FIG. 25). The energy absorption efficiency was slightly reduced by about 1 to 12%.

(Embodiment 9) In this embodiment (FIG. 26), as in Embodiment 8 (FIG. 22), an external reinforcing jig 2c (not shown) is attached to the outer periphery 5b near the lower end of the inclined crushing portion. At the same time, an internal reinforcing jig 1c (not shown) was attached to the inner hole 4b near the lower end of the inclined crushing portion to reinforce the local portion of the FRP cylinder 3 from the outside and the inside. The action of the restraining forces 8b and 7b is shown. Also in this embodiment,
Results similar to those of Example 8 were obtained. (Embodiment 10) In this embodiment (FIG. 27), an internal reinforcing jig 1c (not shown) is attached to the inner hole 4b near the lower end of the inclined crushing portion to reinforce the local portion of the FRP cylinder 3. ,
FIG. 27 shows the action of the restraining force 7b. Also in this example, almost the same results as in Example 8 were obtained.

As described above, the limit angles of Examples 8 to 10 are experimentally obtained by the combination of the FRP cylinder 3 and the internal reinforcing jig 1c and / or the external reinforcing jig 2c. Also,
The internal reinforcing jig 1c and the external reinforcing jig 2c used in Examples 8 to 10 are the same as those used in Example 6 (FIG. 15) and the like. As a result, as the FRP cylinder 3 is crushed, the internal reinforcing jig 1c and the external reinforcing jig 2c move downward, and the pre-crushed portion of the FRP cylinder is sequentially reinforced to maintain the crushing mode.

In the above description, the internal reinforcing jigs 1, 1
a, 1b, 1c and external reinforcing jigs 2, 2a, 2b, 2
Although the elements shown in FIGS. 2 and 20 are adopted as c and 2d, of course, they are not limited to these. Further, the number and arrangement are not limited to those in the embodiment.
Further, the manufacturing method of the FRP cylinder is not limited to the sheet winding method, and may be a manufacturing method such as filament winding.

[0030]

According to the present invention, the following remarkable effects are obtained. 1) By arranging a reinforcing jig in the portion where the dent deformation of the FRP cylinder is likely to occur and adopting a structure that restrains the deformation from the inside and outside of the cylinder, the buckling failure of the cylinder is prevented, and the crush mode of the FRP cylinder is stable. Can be deformed by. Therefore, the collision energy is largely absorbed, and it is possible to improve the energy absorption amount while being lightweight. 2) By attaching an internal and / or external reinforcing jig to the inner hole and / or outer periphery near the end on the crushing start side, the destruction progresses in a stable crushing mode without changing the maximum load at the time of collision. The average load is increased and the energy absorption efficiency can be improved. 3) By attaching an internal reinforcing jig and / or an external reinforcing jig to the inner hole and / or the outer periphery in the vicinity of the end on the crushing start side of the FRP cylinder by adjusting its size, structure, attachment position, etc., It is possible to control the limit angle and stably absorb the oblique collision energy. 4) By moving the internal reinforcing jig and / or the external reinforcing jig in the crushing direction as the crushing progresses, F
The crushing mode is maintained by sequentially reinforcing the part of the RP cylinder before crushing. 5) FRP inside the end of the FRP cylinder opposite to the crush start side
The FRP cylinder is fixed to the mounting member by fitting the protrusion of the mounting member that attaches the cylinder to the vehicle body and the like, and tightening the end portion with an external reinforcing jig. FRP by force
It is possible to prevent the cylinder from falling off from its mounting surface. 6) As the internal reinforcing jig and the external reinforcing jig, for example, known ones such as a stop ring and a tubing band can be used, so that they can be implemented easily and inexpensively. Also,
It can be easily attached and detached.

[Brief description of drawings]

FIG. 1 is an axial sectional view of a first embodiment of the present invention (line BB in FIG. 2).
Sectional view).

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an axial sectional view showing a crushing mode of the first embodiment shown in FIG.

FIG. 4 is a principle diagram of the aspect of reinforcement in the crushing of the first embodiment shown in FIG.

FIG. 5 is an axial sectional view of a second embodiment of the present invention.

FIG. 6 is a principle diagram of a mode of reinforcement of the FRP cylinder of FIG.

FIG. 7 is an axial sectional view of a third embodiment of the present invention.

FIG. 8 is a principle diagram of a mode of reinforcement of the FRP cylinder of FIG.

FIG. 9 is an axial sectional view of a fourth embodiment of the present invention.

FIG. 10 is a principle diagram of a mode of reinforcement of the FRP cylinder of FIG. 9.

FIG. 11 is a load of an example of the present invention and a conventional FRP cylinder-
A diagram showing a displacement curve.

FIG. 12 is an axial sectional view of a fifth embodiment of the present invention.

FIG. 13 is a principle view of a mode of reinforcement of the FRP cylinder of FIG.

FIG. 14 is an axial cross-sectional view showing a crushing mode of Example 5 in FIG.

FIG. 15 is an axial sectional view of a sixth embodiment of the present invention.

FIG. 16 is a principle diagram of a mode of reinforcement of the FRP cylinder of FIG. 15.

FIG. 17 is an axial sectional view of a seventh embodiment of the present invention.

FIG. 18 is a principle view of a reinforcing aspect of the FRP cylinder of FIG.

FIG. 19 is a principle diagram showing a relationship between a binding force and a load in the example of the present invention.

FIG. 20 is a cross-sectional view showing a specific structure of the internal reinforcing jig and the external reinforcing jig shown in FIG.

FIG. 21 is a diagram showing load-displacement curves of the FRP cylinder of the example and the conventional FRP cylinder shown in FIG. 12 and the like.

FIG. 22 is a perspective view showing a usage state of Embodiment 8 of the present invention.

FIG. 23 is a side view of FIG. 22.

FIG. 24 is a principle view of a reinforcing aspect of the FRP cylinder of FIG. 22.

FIG. 25 is a diagram showing a load-displacement curve of oblique compression of a reinforced FRP cylinder and a non-reinforced FRP cylinder of the same example.

FIG. 26 is a principle diagram of a mode of reinforcement of an FRP cylinder according to Example 9 of the present invention.

FIG. 27 is a principle view of a mode of reinforcing the FRP cylinder according to Example 10 of the present invention.

FIG. 28 is an axial sectional view of a conventional FRP cylinder.

FIG. 29 is an axial sectional view showing a deformed state of a conventional FRP cylinder in a crushing mode.

FIG. 30 is a diagram showing an energy absorption amount obtained by general displacement and load.

FIG. 31 is a diagram showing the relationship between 2t / D of the FRP cylinder, the specific energy absorption amount, and the destruction mode.

FIG. 32 is a perspective view showing a recessed state of a conventional FRP cylinder when it is buckled.

FIG. 33 is a perspective view showing a vertical crack in buckling failure of a conventional FRP cylinder.

FIG. 34 is a diagram showing the maximum load and the average load in the load-displacement diagram.

FIG. 35 is a perspective view showing a deformed state of the FRP cylinder due to an oblique compression force of a limit angle or more.

FIG. 36 is a perspective view showing a broken state of an FRP cylinder by an oblique compression force equal to or more than a limit angle.

FIG. 37 is a comparison of energy absorption characteristics (1).

FIG. 38 is a comparison of energy absorption characteristics (2).

FIG. 39 is a comparison of energy absorption characteristics (3).

[Explanation of symbols]

 1 Internal reinforcing jig 1a Internal reinforcing jig 1b Stop ring 2 External reinforcing jig 2a External reinforcing jig 2b Tubing band 2c External reinforcing jig 2d External reinforcing jig 3 Energy absorber (FRP cylinder) 4 Inner hole 4a Crush start Inner hole near the end on the side 4b Inner hole near the lower end of the inclined crushing part 4c Inner hole near the lower end of the FRP cylinder 5 Outer circumference 5a Outer circumference near the end on the crushing start side 5b Outer circumference near the lower end of the inclined crushing part 5c Outer periphery near the lower end of the FRP cylinder 6 Fragment 7 Restraint force 7a Restraint force 7b Restraint force 8 Restraint force 8a Restraint force 8b Restraint force 8c Restraint force 9 Screw 10 Tapered portion 11 Load 12 Recess 12a Recess 12b Swell 13 Vertical crack 14 15 Fixing jig 16 Flat plate part 17 Projection part

Claims (6)

[Claims] 1. A hollow cylindrical energy absorber that absorbs energy at the time of collision, and an internal reinforcing jig and / or an external reinforcing jig that are fitted into the inner hole and / or the outer periphery thereof with an appropriate pressing force. An energy absorber provided with a local reinforcing jig. 2. An energy absorber comprising a local reinforcing jig according to claim 1, wherein a plurality of the internal reinforcing jigs and / or the external reinforcing jigs are arranged along the axial direction of the energy absorbing body. 3. The local reinforcing jig, wherein the internal reinforcing jig and / or the external reinforcing jig is provided in an inner hole and / or an outer periphery of the energy absorber near the end on the crush start side. An energy absorber comprising a tool. 4. The energy absorber provided with the local reinforcing jig according to claim 1 or 3, wherein the internal reinforcing jig and / or the external reinforcing jig moves in the crushing progressing direction as the crushing of the energy absorbing body progresses. . 5. A protrusion of a mounting member for attaching the energy absorber to a vehicle body or the like is fitted into an end portion of the energy absorber opposite to the side where the crushing is started, and the end portion is tightened by the external reinforcing jig. An energy absorber comprising a characteristic local reinforcing jig. 6. The energy provided with the local reinforcing jig of claim 1, claim 3, claim 4, or claim 5, wherein the inner reinforcing jig is a stop ring, and the outer reinforcing jig is a tubing band. Absorber.