JP2005195155A - Energy absorbing body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an energy absorbing body capable of suppressing increase of reaction force of the energy absorbing body in the beginning of a compression breakdown without using a plurality of kinds of fibers as a reinforced fiber, and increasing an energy absorbing amount. <P>SOLUTION: The energy absorbing body 11 is formed of fiber reinforced resin, so that a cross section orthogonal to a compressing direction at the time of being used as the energy absorbing body is changed in the compressing direction and size of a load required for the compression breakdown depends on a position in the compressing direction, and so that the cross section is continuously changed in the compressing direction. Also, the energy absorbing body 11 has a shape bent so that plate material has a plurality of corners 12, and is formed so that the number of the corners 12 existing at the cross section on one end part is larger than that at the cross section on the other end part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an energy absorber, and more particularly to an energy absorber made of a fiber reinforced resin while being used at a site receiving impact force.

  An energy absorber that is displaced at the time of impact and that is compressed and broken and absorbs energy is often provided at a portion that receives an impact, such as a front portion or a rear portion of an automobile body. For example, a front side member and a rear side member of a vehicle are important as a collision energy absorbing member (energy absorber). When the energy absorber is made of metal, the weight increases. Therefore, in order to reduce the weight, the energy absorber is made of a fiber reinforced resin.

As shown in FIG. 9, this type of energy absorber is formed into a cylindrical shape with fiber reinforced resin, and energy absorption using a combination of short fibers, long fibers, glass fibers, and carbon fibers as appropriate as reinforcing fibers. A body 41 has been proposed (see Patent Document 1). A tapered portion 42 is formed at the tip of the energy absorber 41. A θ fiber portion 43 is provided inside the energy absorber 41, a glass fiber portion 44 is provided at the distal end side outside the θ fiber portion 43, and a carbon fiber portion 45 is provided at the proximal end side of the θ fiber portion 43. Is provided. The θ fiber portion 43 means a fiber in which the fibers are arranged so as to form a positive / negative angle θ with respect to the axial direction of the cylinder. In addition, a glass fiber portion 44 and a carbon fiber portion 45 are provided in an intermediate portion of the θ fiber portion 43 so as to overlap each other. In the initial stage of the collision, only the θ fiber portion 43 contributes to increasing the breaking load, and the taper portion 42 exists, so that the breaking occurs at a low load. Thereafter, when the portion where the glass fiber portion 44 and the carbon fiber portion 45 overlap is broken, the load increases and the amount of energy absorption increases. When the destruction further proceeds and the carbon fiber part 45 is destroyed, the load further increases, and the energy absorption amount further increases.
JP-A-8-177922 (paragraph [0009] of the specification, FIG. 1)

  The energy absorber described in Patent Document 1 uses a plurality of types of reinforcing fibers, and by disposing a fiber material having higher strength in order from the fracture start end side to the other end side of the energy absorber. The desired load-displacement change can be obtained. In this case, since the compressive load required for the breakage increases as the breakage proceeds in the axial direction of the energy absorber, the amount of energy absorption can be increased as compared with the case where one type of reinforcing fiber is used. However, it is necessary to use a plurality of fibers, which is troublesome to manufacture.

  The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to increase the reaction force of the energy absorber at the initial stage of compression fracture without using a plurality of types of reinforcing fibers. An object of the present invention is to provide an energy absorber that can be suppressed and can increase the amount of energy absorption.

  In order to achieve the above object, an invention according to claim 1 is an energy absorber formed of a fiber reinforced resin, and a cross-sectional shape orthogonal to a compression direction when used as an energy absorber is the compression direction. And the size of the load necessary for compressive fracture is formed so as to have different portions depending on the position in the compression direction. Here, “the cross-sectional shape changes in the compression direction” does not mean that the size changes in a similar shape, for example, a polygon whose one end side is a quadrangle and the other end side is a pentagon or more. Or is formed so that the number of bent portions is different between the one end side and the other end side.

  Energy absorption by the energy absorber is performed by destruction of the energy absorber, and the amount of energy absorption increases as the load required for destruction is large. When the energy absorber is formed of a fiber reinforced resin, not only the resin is destroyed, but also the reinforcing fiber is destroyed (ruptured), thereby increasing the amount of energy absorption. The energy absorber of the present invention is formed so that the cross-sectional shape changes in the compression direction and the load necessary for the compression fracture has different parts depending on the position in the compression direction. Is broken from a portion having a small load (fracture load) necessary for compressive fracture. Further, as the compressive fracture progresses, the portion with a large fracture load is destroyed. As a result, it is possible to suppress an increase in the reaction force of the energy absorber at the initial stage of compression fracture, and it is possible to increase the energy absorption amount.

  According to a second aspect of the present invention, in the first aspect of the present invention, the cross-sectional shape is formed so as to continuously change in the compression direction. In this invention, the magnitude | size of a load required for the compressive fracture of an energy absorber changes continuously toward the other end side from the one end side of an energy absorber. Therefore, it is possible to suppress an increase in the reaction force of the energy absorber at the initial stage of the compressive fracture by using the large load necessary for the compressive fracture with the base end (root) side being used. In addition to being able to absorb energy stably.

  The invention according to claim 3 is the invention according to claim 1 or claim 2, wherein the cross-sectional shape is a shape in which the plate material is bent so as to have a corner, and is present in a cross section on one end side. The number of corners is larger than the number of corners present in the cross section on the other end side. In this invention, by using the one with more corners as the base end side, it is possible to suppress an increase in the reaction force of the energy absorber at the initial stage of compression fracture and to absorb energy stably. Can do.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that the reaction force of an energy absorber becomes large at the initial stage of a compression fracture, and can increase energy absorption amount, without using multiple types as a reinforced fiber. .

  Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. FIG. 1 is a perspective view of the energy absorber, FIG. 2A is an end view of the tip of the energy absorber, FIG. 1B is an end view of a cut portion at an intermediate portion of the energy absorber, and FIG. It is an end view of a base end.

  The energy absorber is made of fiber reinforced resin. As shown in FIG. 1, the energy absorber 11 has a cross-sectional shape orthogonal to the compression direction (arrow direction in the figure) when used as an energy absorber, and changes in the compression direction. The size is different depending on the position in the compression direction.

  The energy absorber 11 of this embodiment is formed so that the cross-sectional shape continuously changes in the compression direction. The energy absorber 11 has a shape in which the plate material is bent so as to have a plurality of corners 12, and the number of corners 12 present in the cross section at one end is present in the cross section at the other end. It is formed so as to be larger than the number of corner portions 12. The energy absorber 11 has four corners 12 formed at the tip and eight at the base.

  As shown in FIGS. 1 and 2 (a), 2 (b), and 2 (c), the energy absorber 11 has a so-called hat-shaped end surface on the tip side when the energy absorber 11 is used. In addition, the shape of the end surface on the base end side in use is formed into a shape in which two hat-types are continuous. The cross-sectional shape of the intermediate portion is formed such that the hat-shaped central portion is recessed, and the amount of the recess is gradually increased from the distal end side toward the proximal end side. That is, the energy absorber 11 has a substantially U-shaped cross section, and a groove 13 is formed in the center of a member in which both ends of the U-shape are bent 90 degrees outward, and the depth of the groove 13 is toward the base end side. It is formed into a gradually deepening shape. The groove 13 is formed by bending the vicinity of the center of the member. The energy absorber 11 is formed so that the thickness of the plate portion is substantially constant. The energy absorber 11 is formed such that the entire width W and the entire height H are constant in the compression direction.

  The reinforcing fiber of the fiber reinforced resin constituting the energy absorber 11 includes a compression direction fiber bundle arranged so that a fiber bundle made of continuous fibers has a compression direction component of the energy absorber 11, and the fiber bundle is the energy absorber 11. It is comprised by the laminated fiber group which has a 90 degree | times fiber bundle arranged so as to be orthogonal to the compression direction. The compression direction fiber bundle layers and 90 degree fiber bundle layers are alternately laminated. “Arranged so as to have a compression direction component” means arranged parallel to the compression direction or obliquely with respect to the compression direction.

  Carbon fibers are used as continuous fibers constituting the compression direction fiber bundle and the 90 degree fiber bundle. The number of filaments of the carbon fiber is about 6000 to 48000. A thermosetting resin is used as the matrix resin of the energy absorber 11, and an epoxy resin is used in this embodiment.

  The thickness of the plate portion of the energy absorber 11 is about 1.5 to 6 mm, and the thickness of one layer of the compression direction fiber layer and the 90-degree fiber layer is about 0.1 to 1.0 mm. The arrangement pitch of the fiber bundle in the compression direction and the 90-degree fiber bundle is appropriately set depending on the target energy absorption amount.

Next, a method for manufacturing the energy absorber 11 will be described.
First, a laminated fiber group is formed using a frame. As shown in FIGS. 3A and 3B, the frame body 14 is formed in a rectangular shape, and a large number of pins 15a and 15b as restricting members are detachably installed at a predetermined pitch. The pitch of the pins 15a is set according to the arrangement pitch of the compression direction fiber bundles 16a, and the pitch of the pins 15b is set according to the arrangement pitch of the 90-degree fiber bundles 17a. Moreover, the frame 14 is formed in a size capable of forming a laminated fiber group that is larger than the size of the energy absorber 11 to be formed.

  As shown in FIG. 3B, the compression direction fiber bundles 16a are folded and arranged in a state of engaging with the pins 15a, and the compression direction fiber layer 16 is formed. Next, as shown in FIG. 3A, the 90-degree fiber bundle 17a is folded in a state of engaging with the pins 15b and arranged in a direction orthogonal to the compression direction to form the 90-degree fiber layer 17. Thereafter, the arrangement of the compression direction fiber bundles 16a and the arrangement of the 90-degree fiber bundles 17a are repeated to form a laminated fiber group. The fiber bundles are opened when the compression direction fiber bundle 16a and the 90 degree fiber bundle 17a are arranged, and the compression direction fiber bundle 16a and the 90 degree fiber bundle 17a are arranged in a flat state.

  Opening a fiber bundle means expanding the width of the fiber bundle to make it flat. The opening of the fiber bundle is performed, for example, by pressing the fiber bundle when arranging the fiber bundle, and the amount of opening, that is, the degree of flatness can be adjusted by adjusting the pressing force.

  3A and 3B, the arrangement intervals of the compression direction fiber bundles 16a and the 90-degree fiber bundles 17a are widely illustrated, but at least the compression direction fiber bundles 16a are adjacent to each other in the compression direction fiber bundles 16a. Arranged in contact.

  Next, when the compression direction fiber bundle 16a and 90 degree fiber bundle 17a laminated on the frame body 14 are removed from the pins 15a and 15b, the laminated fiber group is prevented from collapsing, and the laminated fiber group is placed in the mold. In order to smoothly perform the placing operation, a shape holding process of the laminated fiber group is performed. In this embodiment, as a form retention treatment, a binding yarn that penetrates the laminated fiber group in the thickness direction is inserted into the laminated fiber group.

  The binding yarn is inserted by a method disclosed in, for example, JP-A-8-218249. Specifically, in the thickness direction of the laminated fiber group, an insertion needle (not shown) having a hole at the tip and hooking a binding thread in the hole is inserted. The insertion needle advances until the hole with the binding yarn hooked passes through the laminated fiber group. Thereafter, the insertion needle is slightly retracted. As a result, the binding yarn is in a state where a U-shaped loop is formed. After the retaining thread is inserted into the loop using the retaining thread needle, the insertion needle is pulled back, and the retaining thread is tightened by the binding thread to form the compression direction fiber layer 16 and the 90-degree fiber layer 17. Combined.

  Next, the impregnation and curing operations of the resin into the laminated fiber group are performed. For resin impregnation and curing, for example, a resin transfer molding (RTM) method is employed. In the RTM method, a laminated fiber group is placed in a resin-impregnated mold (molding mold), a thermosetting matrix resin is injected into the resin-impregnated mold, and the laminated fiber group is impregnated, By heat-curing, the energy absorber 11 (fiber reinforced resin) is manufactured.

  The resin impregnation mold is composed of a lower mold 18 and an upper mold (not shown), and the lower mold 18 has a molding chamber (cavity) 18a corresponding to the outer shape of the energy absorber 11 as shown in FIG. It constitutes a female mold. On the other hand, the upper mold is configured as a male mold having a convex portion accommodated in the molding chamber 18a with a certain distance from the inner surface of the molding chamber 18a.

  An injection hole and a vent hole are formed in the upper mold, a nipple connected to the injection line of the matrix resin is connected to the injection hole, and a nipple for connecting to a pipe line connected to the decompression device is connected to the vent hole. Are connected. The lower mold 18 and the upper mold are fastened and fixed by bolts (not shown) with a seal ring (not shown) interposed therebetween.

  Prior to housing the laminated fiber group in the resin-impregnated mold, the outer shape is processed. “Outer shape processing” means cutting the periphery of the laminated fiber group in order to bring the laminated fiber group into a size and a developed state corresponding to the shape of the energy absorber 11.

  After performing the outer shape processing, the laminated fiber group is accommodated (set) in the molding chamber 18 a of the lower mold 18. Next, the convex part of the upper mold is inserted into the molding chamber 18a of the lower mold 18, and the lower mold 18 and the upper mold are tightened with bolts. As a result, the laminated fiber group is housed between the lower mold 18 and the upper mold.

  Next, the resin is injected with the injection hole side connected to the injection line and the vent hole side connected to the line. First, the valve on the injection line side is closed and the pressure in the molding chamber 18a is reduced, and then the valve is opened to inject resin into the resin impregnation mold from the injection hole. And after confirming the overflow of the resin from a vent hole with the glass-made decompression trap provided in the middle of the pipe line, the valve on the pipe line side is closed and the inside of the resin impregnation mold is pressurized. In this state, the valve on the injection pipe side is closed and the resin impregnation mold is heated to cure the matrix resin. Next, after the resin-impregnating mold is cooled, the resin-impregnating mold is opened, the molded product is taken out, and deburring is performed to complete the manufacture of the energy absorber 11.

  For example, as shown in FIG. 5, the energy absorber 11 configured as described above is fixed to a portion that receives an impact while being supported by the support 19 on the proximal end side, and receives a compressive load from the distal end side. Used in state. If a compressive load acts on the energy absorber 11 and the size thereof is a size that causes the energy absorber 11 to break, the energy absorber 11 is broken and energy is absorbed. When the energy absorber 11 is destroyed, not only the resin of the fiber reinforced resin constituting the energy absorber 11 but also the reinforcing fibers are broken, so that a load necessary for the destruction increases and the amount of energy absorption increases.

  In the energy absorber 11, the thickness of the plate member portion is substantially constant, and the arrangement density of the fiber bundles 16a in the compression direction in each portion is formed to be substantially constant. Therefore, the smaller the area of the cross section perpendicular to the compression direction, the smaller the breakage. It is destroyed by load. Further, if the corner portion 12 is present, the 90-degree fiber bundle 17a is broken at the corner portion 12, and accordingly, a larger load is required for the breakage. Since the energy absorber 11 is formed to have a smaller cross-sectional area toward the tip side, at the initial stage of compression fracture, the tip side having a small cross-sectional area perpendicular to the compression direction is broken with a small compressive load. In addition, since the number of corner portions 12 is small, it becomes easier to break with a small load. As the compression fracture progresses, the portion having a large cross-sectional area and a large amount of fiber bundle is broken, so that the compression load increases and the amount of energy absorption increases. That is, after the initial load of compressive fracture is reduced and the fracture is started, the fracture progresses successively, and the fracture progresses stably and energy is absorbed without suddenly increasing the compressive load.

This embodiment has the following effects.
(1) The energy absorber 11 is formed of a fiber reinforced resin, the cross-sectional shape orthogonal to the compression direction when used as the energy absorber 11 changes in the compression direction, and the size of the load necessary for compression fracture is compressed. It is formed differently depending on the position in the direction. Therefore, at the initial stage of the compressive fracture, the fracture is started from a portion having a small load (destructive load) necessary for the compressive fracture. Further, as the compressive fracture progresses, the portion with a large fracture load is destroyed. As a result, it is possible to suppress an increase in the reaction force of the energy absorber 11 at the initial stage of compression fracture, and it is possible to increase the amount of energy absorption.

  (2) The energy absorber 11 is formed such that the cross-sectional shape orthogonal to the compression direction continuously changes in the compression direction. Therefore, it is possible to suppress the reaction force of the energy absorber 11 from increasing at the initial stage of the compressive fracture by using the side where the magnitude of the load necessary for the compressive fracture is the base end (root) side. And can absorb energy stably.

  (3) The cross-sectional shape orthogonal to the compression direction of the energy absorber 11 is a shape in which the plate is bent so as to have a plurality of corners 12, and the number of corners 12 present in the cross section on one end side. Is formed to be larger than the number of corners 12 existing in the cross section on the other end side. Therefore, by using the side with more corners 12 as the base end side, it is possible to suppress an increase in the reaction force of the energy absorber 11 at the initial stage of compression fracture and to absorb energy stably. Can do.

  (4) The energy absorber 11 has a substantially U-shaped cross section, and both ends of the U-shape are bent 90 degrees outward to be bent in the vicinity of the center of the member, so that the groove 13 is formed. It is bent and formed in a shape that gradually becomes deeper toward the side. Accordingly, it is easy to form the energy absorber 11 so that the cross-sectional area increases toward the base end side in a state where the entire width W and the entire height H of the energy absorber 11 are constant in the compression direction.

  (5) As a shape retention treatment when the laminated fiber group is impregnated with resin, a binding thread penetrating in the thickness direction is inserted into the laminated fiber group. Therefore, when the compressive load acts on the energy absorber 11 and the energy absorber 11 is broken, the binding yarn functions to prevent delamination between the compression direction fiber layer 16 and the 90-degree fiber layer 17. More energy is needed for destruction. As a result, the amount of energy absorption can be increased as compared to the case where a method of temporarily fixing a part of the compression direction fiber layer 16 and the 90-degree fiber layer 17 with an adhesive or the like is adopted as the shape retention treatment.

  (6) The compression direction fiber bundles 16a are arranged and arranged so that the adjacent compression direction fiber bundles 16a are in contact with each other. Therefore, compared with the case where the adjacent fiber bundles 16a in the compression direction are completely separated from each other by the resin, the energy required for the compression fracture is increased and the energy absorption amount is increased.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG. This embodiment is different from the first embodiment in that the energy absorber 11 is configured in a closed shape. Here, the “closed shape” means a shape having a rib on a cylindrical or cylindrical peripheral surface. The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The energy absorber 11 is formed in a cylindrical shape having a square front end and a hexagonal base end when used as an energy absorber. That is, the energy absorber 11 has four corners 12 formed on the distal end side and six corners 12 formed on the proximal end side. The energy absorber 11 has a constant thickness and is formed so that the area of the cross section perpendicular to the compression direction increases toward the proximal end side.

  When the energy absorber 11 of this embodiment is manufactured, the laminated fiber group is formed using the frame body 14, and until the shape retention treatment is performed by inserting the binding yarn into the laminated fiber group, the first embodiment is used. The same. A resin-impregnating mold used for resin impregnation and curing with respect to the laminated fiber group is formed so that the shape of the molding chamber (cavity) forms the outer shape of the energy absorber 11. In addition, a prismatic shape having a shape corresponding to the inner shape of the energy absorber 11 is used as the inner mold. The inner mold around which the laminated fiber group is wound is placed in the molding chamber of the resin impregnation mold, and the resin is cured after the laminated fiber group is impregnated with the resin.

  The energy absorber 11 of this embodiment is also used in a state where the side on which many corners 12 are formed is the base end. The second embodiment has the following effects in addition to the same effects as (1), (3), (5), and (6) of the first embodiment.

(7) Since the energy absorber 11 is in a closed shape, it is difficult to buckle even with a simple shape as compared with a shape in which a plate material is folded in a state where there is no closed space.
(8) Although the energy absorber 11 has a closed shape, since the corner portion 12 is only convex outward, the manufacturing becomes easier as compared with a shape including the convex corner portion 12 inside. .

The embodiment is not limited to the above, and may be embodied as follows, for example.
○ If the energy absorber 11 is formed so that the cross-sectional shape orthogonal to the compression direction in use changes in the compression direction and the magnitude of the load required for compression fracture has different parts depending on the position in the compression direction Well, it is not limited to the shape of the first and second embodiments. For example, as shown in FIG. 7, the energy absorber 11 may have a shape in which the shape of the first embodiment is combined with a flat plate. Moreover, the cross-sectional shape orthogonal to the compression direction of the energy absorber 11 may be wavy and formed so that the number of waves is small on the distal end side and larger on the proximal end side.

  ○ When the energy absorber 11 has a cross-sectional shape that is bent so that the plate has corners, the number of corners present in the cross section on one end side is the cross section on the other end side. It suffices if the number of corners is larger than the number of corners present, and the number of corners present at one end is not limited to a plurality and may be one.

  ○ When the cross section of the energy absorber 11 is bent so that the plate has corners, the cross section on one end side has no corners, and the cross section on the other end side has corners. May be formed.

  (Circle) the energy absorber 11 is not restricted to the shape where the cross-sectional shape orthogonal to a compression direction changes continuously in the said compression direction. For example, in 1st Embodiment, you may form so that the groove | channel 13 may not start immediately from the front-end | tip of the energy absorber 11, but may start in the middle of a compression direction.

  When the energy absorber 11 is deformed into a predetermined shape by putting a flat laminated fiber group into a mold, the thickness of the laminated fiber group varies depending on the volume content of the fiber bundle, but is 3 mm or less. In this case, the flat laminated fiber group can be smoothly deformed corresponding to the cavity shape of the mold.

  The energy absorber 11 may be formed so that the thickness of the plate member portion is not limited to a constant value, and becomes thicker toward the base end side when used as an energy absorber. As a method of increasing the thickness toward the base end side, when forming the laminated fiber group using the frame body 14, as shown in FIG. 8, the arrangement density of the compression direction fiber bundles 16 a is set to one side in the compression direction of the energy absorber 11 (base You may arrange so that it may become low gradually toward the other side (front end side) from an end side. In this case, most of the compression direction fiber bundles 16a are not parallel to the compression direction of the energy absorber 11, but are arranged in a state inclined with respect to the compression direction. Further, the arrangement density of the 90-degree fiber bundle 17a is arranged so as to gradually decrease from one side in the compression direction of the energy absorber 11 to the other side, or both of the compression-direction fiber bundle 16a and the 90-degree fiber bundle 17a are arranged. The arrangement density may be arranged so as to gradually decrease from one side in the compression direction of the energy absorber 11 to the other side.

  ○ The thickness of the plate portion of the energy absorber 11 is constant, and at least one of the arrangement densities of the compression direction fiber bundle 16a and the 90 degree fiber bundle 17a constituting the laminated fiber group is the compression direction of the energy absorber 11. You may arrange so that it may become low gradually toward the other side from one side. Also in this case, since the arrangement density of the fiber bundles on the proximal end side of the energy absorber 11 is increased, the load necessary for compressive fracture is increased and energy is effectively absorbed.

  The laminated fiber group may be formed by laminating woven fabrics instead of arranging the compression direction fiber bundles 16a, the 90-degree fiber bundles 17a, and the like using the frame body 14. In this case as well, the binding yarn is inserted in the same manner as in the above embodiment.

  ○ When manufacturing the cylindrical energy absorber 11, both ends of a flat laminated fiber group formed using the frame body 14 are overlapped, and the overlapped portion is sewn with a sewing machine, or a binding thread and a retaining thread Or a cylindrical laminated fiber group may be formed by covering with a mold corresponding to the shape of the energy absorber 11 and impregnating with a resin.

  In the production of the energy absorber 11, when a laminated fiber group is formed and then a shape retention treatment is performed, instead of a method of binding to the laminated fiber group with a binding yarn, a fiber bundle in the compression direction is used with an adhesive, a thermoplastic resin, or the like. The 16a and 90 degree fiber bundles 17a may be temporarily fixed in some places. As the pressure-sensitive adhesive, a rubber / resin-based pressure-sensitive adhesive in which rubber is the main material and a resin is combined as a tackifier (tackifier) may be used. In the case of temporarily fixing with a pressure-sensitive adhesive or the like without using a binding yarn for the shape retention treatment of the laminated fiber group, the support used for the arrangement of the compression direction fiber bundle 16a and the 90 degree fiber bundle 17a is not the frame body 14 but supported. You may use what fixed the pins 15a and 15b around the board.

  The laminated fiber group only needs to be arranged so that the fiber bundles are at least biaxially oriented, and the fiber bundles (bias yarns) arranged in a direction intersecting with both the compression direction fiber bundle 16a and the 90 degree fiber bundle 17a. May be provided.

  ○ Fiber bundle 16a in the compression direction, 90 degree fiber bundle 17a, constraining yarn, and retaining yarn are not limited to carbon fiber, but various kinds of glass fiber, polyaramid fiber, etc. depending on the required performance and application of energy absorber 11 Things may be used.

(Circle) you may use the fiber bundle from which thickness differs as a fiber bundle which comprises the compression direction fiber bundle 16a and the 90 degree | times fiber bundle 17a.
(Circle) not only an epoxy resin as a thermosetting resin which comprises the energy absorber 11, but a phenol resin, unsaturated polyester resin, etc. may be used.

  A thermoplastic resin may be used in place of the thermosetting resin as the matrix resin constituting the energy absorber 11. When a thermoplastic resin is used as the matrix resin, the laminated fiber group is impregnated with a thermoplastic resin by a general impregnation method such as a melt impregnation molding method, and cooled to form the energy absorber 11. As the thermoplastic resin, for example, nylon, polybutylene terephthalate, polycarbonate or the like is used.

  ○ When a thermoplastic resin is used as the matrix resin constituting the energy absorber 11, use is made of a state in which the entire fiber bundle is impregnated with the thermoplastic resin, and the compression direction fiber bundle 16a and the 90 degree fiber bundle 17a After the arrangement, the energy absorber 11 may be manufactured by integrally manufacturing a plate material, setting the plate material in a mold, and softening by heating.

The following technical idea (invention) can be understood from the embodiment.
(1) In invention of Claim 3, the energy absorber is comprised by the closed shape.

  (2) In the invention described in the technical idea (1), the energy absorber is formed in a cylindrical shape whose corners are only convex outward.

The schematic perspective view of the energy absorber of 1st Embodiment. (A) is an end view of the front end of the energy absorber, (b) is an end view of a cut portion in an intermediate portion of the energy absorber, and (c) is an end view of a base end of the energy absorber. (A), (b) is a schematic top view which shows the arrangement | sequence state of a fiber bundle. The perspective view of a metal mold | die. The perspective view which shows the attachment state of an energy absorber. The model perspective view of the energy absorber of 2nd Embodiment. The model perspective view of the energy absorber of another embodiment. The schematic diagram which shows the arrangement | sequence state of the compression direction fiber bundle of another embodiment. The schematic cross section of a prior art.

Explanation of symbols

  11 ... energy absorber, 12 ... corner.

Claims (3)

  An energy absorber formed of a fiber reinforced resin, wherein a cross-sectional shape perpendicular to the compression direction when used as an energy absorber changes in the compression direction, and the magnitude of a load necessary for compression fracture is in the compression direction. An energy absorber formed so as to have different parts depending on positions.   The energy absorber according to claim 1, wherein the cross-sectional shape is formed so as to continuously change in the compression direction.   The cross-sectional shape is a shape in which the plate material is bent so as to have corners, and the number of corners existing in the cross section on one end side is larger than the number of corners existing in the cross section on the other end side. The energy absorber according to claim 1 or 2, wherein the energy absorber is formed as follows.

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