JP6560568B2 - Energy absorbing structure - Google Patents

Description

  The present invention relates to an energy absorbing structure.

  The vehicle is provided with an energy absorbing member that is crushed when a collision occurs and absorbs the collision energy. A typical example of the energy absorbing member is a crush box disposed between the front bumper beam and the front frame. Conventionally, an energy absorbing member made of a metal material such as a steel plate has been used. In recent years, a fiber reinforced resin (FRP) tube in which reinforcing fibers such as carbon fibers are mixed to reduce the weight of the vehicle body. Shaped energy absorbing members have been put into practical use.

  The fiber-reinforced resin energy absorbing member is compressed in the axial direction by being compressed when a collision load is input. Here, when the collision load is input, the energy absorbing member and members around the energy absorbing member may be deformed by external force, and thus the energy absorbing member may be inclined. When the posture of the energy absorbing member is inclined, the inclination of the energy absorbing member in the axial direction with respect to the input direction of the collision load increases, so that the ratio of the collision load spent for compressive deformation in the axial direction of the energy absorbing member can be reduced. Thereby, the energy absorption amount in the crushing of the energy absorbing member can be reduced. Therefore, a technique for preventing the energy absorbing member from tilting has been proposed.

  For example, in Patent Document 1, in an energy absorbing member composed of a plurality of bundled cylinders, in order to prevent collapse at the base of the cylinder and to cause each cylinder to stably compress in the axial direction, A technique is disclosed in which a bend preventing means for preventing a base end portion of a cylinder from being bent in the vicinity of a joint portion between an end portion and an attachment surface portion thereof is disclosed.

JP 2010-1111239 A

  Here, since the energy absorbing member made of fiber reinforced resin is more easily damaged than the crash box made of steel plate, when using the energy absorbing member made of fiber reinforced resin for a vehicle, it is necessary to consider chipping resistance, weather resistance, etc. There is. Specifically, it is desired to prevent the energy absorbing member from being damaged by pebbles or rainwater splashed by the wheels. As a countermeasure, it is conceivable to cover the outer peripheral surface of the energy absorbing member with a cover member. Such a cover member receives a part of the collision load when the collision load is input, and collapses in the axial direction together with the collapse of the energy absorbing member.

  However, when the outer peripheral surface of the energy absorbing member is covered with the cover member, at the initial stage of the cover member crushing process due to the input of the collision load, the side opposite to the input side of the collision load of the cover member before the entire cover member is crushed Bending deformation may occur at the ends of the. In such a case, the posture of the energy absorbing structure including the cover member and the energy absorbing member can be inclined. Thereby, since the inclination of the energy absorbing member in the axial direction with respect to the input direction of the collision load is increased, the ratio of the collision load spent for compressive deformation in the axial direction of the energy absorbing member can be reduced. Therefore, the energy absorption amount in the crushing of the energy absorbing member can be reduced.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is a new and improved that can suppress a decrease in the amount of energy absorption in the collapse of the energy absorbing member. It is to provide an energy absorbing structure.

In order to solve the above problems, according to an aspect of the present invention, a cylindrical energy absorbing member made of a fiber reinforced resin that is crushed in the axial direction and absorbs collision energy when a collision load is input, and the energy absorbing member covering the outer peripheral surface of a cylindrical cover member for crushing in the axial direction when the input of the impact load, provided on the inner peripheral surface of the end portion opposite to the input side of the front SL collision load of the cover member There is provided an energy absorbing structure comprising: a rib extending in the axial direction of the cover member over a part of the entire length of the cover member from the end portion . In order to solve the above problem, according to another aspect of the present invention, a cylindrical energy absorbing member made of a fiber reinforced resin that collapses in the axial direction and absorbs collision energy when a collision load is input, A cylindrical cover member that covers the outer peripheral surface of the energy absorbing member and collapses in the axial direction when the collision load is input, and at least the inner peripheral surface side of the end of the cover member opposite to the input side of the collision load And an rib that extends in the axial direction of the cover member, and the rib is adjacent to an outer peripheral surface of an end portion of the energy absorbing member opposite to the input side. Is provided. In order to solve the above problem, according to another aspect of the present invention, a cylindrical energy absorbing member made of a fiber reinforced resin that collapses in the axial direction and absorbs collision energy when a collision load is input, A cylindrical cover member that covers the outer peripheral surface of the energy absorbing member and collapses in the axial direction when the collision load is input, and at least the inner peripheral surface side of the end of the cover member opposite to the input side of the collision load A first rib extending in the axial direction of the cover member, and at least either the inner peripheral surface side or the outer peripheral surface side of the end of the energy absorbing member opposite to the input side On the other hand, there is provided an energy absorbing structure provided with a second rib extending in the axial direction of the energy absorbing member.

  The cover member may have a cross-sectional shape that expands from the collision load input side toward the side opposite to the input side.

  The cover member may have a polygonal cross section.

  A holding member that holds an end of the energy absorbing member opposite to the input side of the collision load, and the holding member has an opening at a position corresponding to the internal space of the energy absorbing member; Also good.

  As described above, according to the present invention, it is possible to suppress a decrease in energy absorption amount due to the collapse of the energy absorbing member.

It is sectional drawing which shows an example of the energy absorption structure which concerns on embodiment of this invention. It is sectional drawing which shows a cross section substantially perpendicular | vertical to the axial direction of the energy absorption structure shown in FIG. It is a schematic diagram which shows the mode of progress of the sequential destruction of the energy absorption structure which concerns on the same embodiment. It is a schematic diagram which shows the mode of progress of the sequential destruction of the energy absorption structure which concerns on the same embodiment. It is explanatory drawing which shows an example of the relationship between the crushing stroke and crushing load in the crushing of the energy absorption structure which concerns on the embodiment. It is sectional drawing which shows an example of the energy absorption structure which concerns on a 1st modification. It is sectional drawing which shows an example of the energy absorption structure which concerns on a 2nd modification. It is sectional drawing which shows an example of the energy absorption structure which concerns on a 3rd modification. It is sectional drawing which shows an example of the energy absorption structure which concerns on a 4th modification.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

<1. Energy absorbing structure>
First, with reference to FIG. 1, the energy absorption structure 10 which concerns on this embodiment is demonstrated.

  FIG. 1 is a cross-sectional view showing an example of an energy absorbing structure 10 according to the present embodiment. FIG. 1 is a cross-sectional view showing a state where the energy absorbing structure 10 is attached between a front bumper beam 30 and a front frame 50 of a vehicle. FIG. 1 is a view of the state in which the energy absorbing structure 10 is held as viewed from above the vehicle. In the following description, the front bumper beam 30 side of the energy absorbing structure 10 may be referred to as a front end side, and the front frame 50 side may be referred to as a rear end side.

  The energy absorbing structure 10 includes an energy absorbing member 100, a fixing member 300, a holding member 500, a cover member 700, and a rib 900. The energy absorbing member 100 has a front end side fixed to the fixing member 300 and a rear end side held by a holding member 500. The fixing member 300 is joined to the front bumper beam 30. The holding member 500 is joined to the front end side of the front frame 50. The energy absorbing structure 10 is disposed between the front bumper beam 30 and the front frame 50, and the front end side fixed to the front bumper beam 30 is an input side of a collision load.

(1-1. Energy absorbing member)
The energy absorbing member 100 receives a collision load when the vehicle collides with a preceding vehicle, an obstacle, or another target object, and absorbs collision energy. The energy absorbing member 100 also plays a role of efficiently transmitting the collision load to the front frame 50 when the collision load is large. The energy absorbing member 100 is a cylindrical member formed of fiber reinforced resin. In this embodiment, the energy absorbing member 100 is a multi-layer composite material formed using a carbon fiber reinforced resin (CFRP) using a thermosetting resin and carbon fiber, and has high strength and light weight. Can be realized.

  In the present embodiment, the energy absorbing member 100 has a cylindrical shape. The energy absorbing member 100 made of fiber reinforced resin receives a load (crush load) when a collision load is input, and is crushed while sequentially breaking from the tip side. Since the energy absorbing member 100 made of fiber reinforced resin is buckled or sequentially broken at a small interval as compared with the crash box made of steel plate, it is possible to realize stable impact energy absorption with little load fluctuation. Further, the energy absorbing member 100 made of fiber reinforced resin has the characteristics that the remaining amount of crushing is relatively small and the amount of impact energy absorbed per unit weight is large. The fiber reinforced resin-made energy absorbing member 100 can be, for example, a braid composed of a braided string and a vertical string using a fiber material and a thermoplastic resin.

  The reinforcing fiber used for the fiber reinforced resin constituting the energy absorbing member 100 is not particularly limited. For example, carbon fibers, ceramic fibers such as glass fibers, organic fibers such as aramid fibers, and reinforcing fibers obtained by combining these fibers can be used. Among these, carbon fibers are preferably included from the viewpoint of having high mechanical properties and ease of strength design.

  Further, the matrix resin of the fiber reinforced resin constituting the energy absorbing member 100 may be a thermosetting resin or a thermoplastic resin. In the case of a thermosetting resin, examples of the main material include epoxy resins, unsaturated polyester resins, vinyl ester resins, phenol resins, polyurethane resins, and silicon resins. The thermosetting resin may be one of these or a mixture of two or more. When these thermosetting resins are employed as the matrix resin, an appropriate curing agent or reaction accelerator may be added to the thermosetting resin.

  In the case of a thermoplastic resin, the main materials include, for example, polyolefin resins such as polyethylene and polypropylene, polyvinyl chloride resins, ABS resins, polystyrene resins, AS resins, polyamide resins such as nylon 6 and nylon 66, and polyacetal resins. , Polycarbonate resins, polyethylene terephthalate, polybutylene terephthalate and other thermoplastic polyester resins, PPS (polyphenylene sulfide) resins, fluororesins, polyetherimide resins, polyetherketone resins, polyimide resins, polyethersulfone resins, aromatic polyamide resins Etc. are exemplified.

  The thermoplastic resin may be one of these, or a mixture of two or more. In the case of a mixture, a compatibilizer may be used in combination. Furthermore, brominated flame retardants, silicon-based flame retardants, red phosphorus, and the like may be added as flame retardants. It is preferable to use a thermoplastic resin for automobile parts that are required to be relatively mass-produced from the viewpoint of ease of molding and mass productivity.

  Further, the energy absorbing member 100 having a cylindrical shape is arranged such that the axial direction is along the front-rear direction of the vehicle. The dimensions of the energy absorbing member 100 can be appropriately designed according to the size of the vehicle, the load characteristics to be obtained, the weight of the energy absorbing member 100, and the like. For example, the axial length of the energy absorbing member 100 is 130 to 200 mm, the diameter of the inner space is 40 to 70 mm, and the thickness is 3 mm.

  The energy absorbing member 100 has a reduced diameter portion 102 whose outer periphery is reduced in diameter toward the end portion on the distal end side. When the distal end side of the energy absorbing member 100 is pressed by the reduced diameter portion 102, peeling is likely to occur between a plurality of layers constituting the energy absorbing member 100. Thereby, the trigger of the destruction of the front end side of the energy absorption member 100 is given, and it can be made easy to produce the progress of the sequential destruction from the front end side of the energy absorption member 100 to the rear end side.

(1-2. Fixing member)
The fixing member 300 is a member that is bonded to the front bumper beam 30 and that fixes the front end side of the energy absorbing structure 10. The fixing member 300 is also called, for example, a bumper stay. The fixing member 300 is made of, for example, a metal material typified by a steel plate or the like, aluminum, or the like. When a vehicle collision occurs, the fixing member 300 transmits the impact received by the front bumper beam 30 to the energy absorbing structure 10.

  In the energy absorbing structure 10 shown in FIG. 1, the end portion on the distal end side of the energy absorbing member 100 is fixed to the fixing member 300 with an adhesive or the like. As an adhesive that can be used for joining the energy absorbing member 100 and the fixing member 300, an epoxy resin-based, acrylic resin-based, urethane resin-based adhesive, or the like can be used as appropriate. Note that, when the energy absorbing member 100 is firmly held by the holding member 500, the end portion on the distal end side of the energy absorbing member 100 may not be joined to the fixing member 300.

(1-3. Holding member)
The holding member 500 is attached to the front end side of the front frame 50 and holds the end portion on the rear end side of the energy absorbing member 100. The holding member 500 is a plate-like member made of, for example, a metal material typified by a steel plate or the like, aluminum, or the like. In the energy absorbing structure 10 shown in FIG. 1, the end portion on the rear end side of the energy absorbing member 100 is fixed to the holding member 500 with an adhesive or the like. As an adhesive that can be used for joining the energy absorbing member 100 and the holding member 500, an epoxy resin-based, acrylic resin-based, urethane resin-based adhesive, or the like can be used as appropriate.

  Further, the holding member 500 is provided with an opening 502 at a position corresponding to the internal space of the energy absorbing member 100. The opening 502 is a passage that discharges at least a part of the crush of the energy absorbing member 100 that has been destroyed by the inner winding to the outside of the energy absorbing member 100 when the energy absorbing member 100 is crushed. Therefore, the increase in the remaining crushing of the energy absorbing member 100 due to the destroyed crushing residue accumulated in the internal space of the energy absorbing member 100 is suppressed. Instead of the opening 502, a recess protruding toward the front frame 50 may be provided.

(1-4. Cover member)
The cover member 700 is a cylindrical member that covers the outer peripheral surface of the energy absorbing member 100. The cover member 700 protects the energy absorbing member 100 by preventing foreign objects such as pebbles that are flipped up by the wheels from colliding with the energy absorbing member 100 or attaching rainwater to the energy absorbing member 100. Yes. In this embodiment, the cover member 700 is made of a thin steel plate, but may be made of a light metal plate such as aluminum or a resin.

  Further, the cover member 700 receives a part of the collision load when the collision load is input, and is crushed in the axial direction together with the collapse of the energy absorbing member 100. In the energy absorbing structure 10 according to the present embodiment, the energy absorbing member 100 mainly bears the collision load, and the cover member 700 bears the collision load. Therefore, regardless of the constituent material of the cover member 700, a relatively stable load characteristic can be obtained when the energy absorbing structure 10 is crushed.

  The end of the cover member 700 on the front end side is joined to the fixing member 300. Further, the end portion on the rear end side of the cover member 700 is joined to the holding member 500. The cover member 700, the fixing member 300, and the holding member 500 can be joined by various methods such as welding or joining with an adhesive. When the front bumper beam 30 is pulled forward, for example, when the vehicle is towed, a tensile force is applied to the energy absorbing structure 10. In the present embodiment, since the cover member 700 is joined to the fixing member 300 and the holding member 500, a part of the pulling force applied to the energy absorbing structure 10 when the vehicle is towed can be received by the cover member 700. Therefore, deformation and breakage of the energy absorbing member 100 when the vehicle is towed can be suppressed.

  2 is a cross-sectional view showing an AA cross section substantially perpendicular to the axial direction of the energy absorbing structure 10 shown in FIG. As shown in FIG. 2, the cover member 700 may have a polygonal cross section. As a result, corner portions that are likely to bear a load are provided in the cover member 700, so that it is possible to increase the amount of energy absorbed when the cover member 700 is crushed when a collision load is input. In addition, the cross section of the cover member 700 is not limited to the example, and may have other shapes, for example, a polygon having another number of corners, a substantially circular shape, a substantially elliptical shape, or the like. .

(1-5. Ribs)
The rib 900 is a member provided to suppress bending deformation at the end portion on the rear end side of the cover member 700 in the initial stage of crushing. The rib 900 is made of, for example, a metal material such as a steel material or aluminum, a resin, or the like. As shown in FIG. 1, the rib 900 is provided on the inner peripheral surface side of at least the rear end side of the cover member 700, and extends in the axial direction of the cover member 700. Specifically, the rib 900 contacts the inner peripheral surface of the end portion on the rear end side of the cover member 700 and the front end side surface of the holding member 500, and the inner peripheral surface of the end portion on the rear end side of the cover member 700. And it joins with at least one of the surface of the front end side of the holding member 500 by welding or an adhesive agent. The rib 900 may be formed integrally with the cover member 700 or the holding member 500. Further, the rib 900 may extend from the end on the rear end side to the end on the front end side on the inner peripheral surface side of the cover member 700.

  Moreover, in this embodiment, as shown in FIG.1 and FIG.2, the cross-sectional shape of the rib 900 in the cross section substantially perpendicular | vertical to the axial direction of the cover member 700 expands as it goes to a rear end side from the front end side. As a result, the rib 900 is likely to buckle from the tip side when a collision load is input. Therefore, it is possible to suppress the occurrence of uncrushed ribs 900 and obtain a large energy absorption amount.

  As shown in FIG. 2, a plurality of ribs 900 may be provided at intervals in the circumferential direction of the cover member 700. For example, the plurality of ribs 900 are provided at equal intervals in the circumferential direction. Thereby, it is possible to reduce variation in strength of the cover member 700 in the circumferential direction. Note that the arrangement and number of ribs 900 are not limited to the example, and may be different from the arrangement and number shown in the drawings.

  In the present embodiment, since the rib 900 extending in the axial direction of the cover member 700 is provided on the inner peripheral surface side of the end portion on at least the rear end side of the cover member 700, the end portion on the rear end side of the cover member 700 is provided. The bending rigidity can be increased. Thereby, at the initial stage of the crushing process of the cover member 700 due to the input of the collision load, it is possible to suppress the occurrence of bending deformation at the end portion on the rear end side of the cover member 700 before the entire cover member 700 is crushed. . Therefore, when the energy absorbing structure 10 is crushed, the posture of the energy absorbing structure 10 can be suppressed from being inclined. Therefore, since the increase in the axial inclination of the energy absorbing member 100 with respect to the input direction of the collision load can be suppressed, a decrease in the ratio of the collision load spent on the axial compression deformation of the energy absorbing member 100 can be suppressed. obtain. Therefore, it is possible to suppress a decrease in the amount of energy absorption when the energy absorbing member 100 is crushed.

<2. Crushing action of energy absorbing structure>
So far, the configuration of the energy absorbing structure 10 according to the present embodiment has been described. Next, the progress of sequential destruction of the energy absorbing structure 10 according to the present embodiment will be described. 3 and 4 are schematic diagrams showing the progress of sequential destruction of the energy absorbing structure 10.

  When a vehicle collision occurs and a collision load is input to the energy absorbing structure 10, the energy absorbing member 100 and the cover member 700 are compressed and begin to collapse in the axial direction. In the initial stage of the crushing, as shown in FIG. 3, the energy absorbing member 100 is broken while the front end side opens to the inner winding and the outer winding.

  In the present embodiment, since the rib 900 is provided on the inner peripheral surface side of the end portion on the rear end side of the cover member 700, the bending rigidity of the end portion on the rear end side of the cover member 700 is compared with the portion on the front end side. Big. Therefore, at the initial stage of crushing, as shown in FIG. 3, the cover member 700 starts to buckle from the front end portion without causing bending deformation at the rear end portion. And destruction progresses sequentially so that the range which destruction in energy absorption member 100 may spread to the back end side.

  FIG. 4 shows a state in which sequential destruction of the energy absorbing structure 10 has further progressed from the state shown in FIG. When sequential destruction of the energy absorbing structure 10 progresses, as shown in FIG. 4, the end portion on the tip side of the rib 900 comes into contact with the fixing member 300, and a load starts to be transmitted to the rib 900 via the fixing member 300. The rib 900 receiving the load starts to buckle from the end portion on the front end side.

  FIG. 5 is an explanatory diagram illustrating an example of a relationship between a crush stroke and a crush load in crushing the energy absorbing structure 10 according to the present embodiment. When a collision load is input to the energy absorbing structure 10, the collapsing load of the energy absorbing structure 10 increases until the amount of crushing stroke becomes St1 as the energy absorbing member 100 starts to collapse. After that, the state in which the crushing of the energy absorbing member 100 and the cover member 700 shown in FIG. 3 progresses as an example continues until the crushing stroke amount becomes St2. As shown in FIG. 5, the crushing load is substantially constant until the crushing stroke amount becomes St1 to St2. When the crushing stroke amount exceeds St2, as shown in FIG. 4, the rib 900 starts to buckle and the crushing load increases.

  In the present embodiment, the cross-sectional shape of the rib 900 in a cross section substantially perpendicular to the axial direction of the cover member 700 increases from the front end side toward the rear end side. Therefore, when the amount of crushing stroke exceeds St2, the crushing load increases according to the shape of the cross section substantially perpendicular to the axial direction at the axial position where the rib 900 buckles. Thus, since the characteristics of the crushing load received by the energy absorbing structure 10 depend on the shape of the rib 900, the shape of the rib 900 can be appropriately set to a shape that can obtain a desired crushing load characteristic.

  In the present embodiment, an opening 502 is provided in the center of the holding member 500 that holds the rear end side of the energy absorbing member 100. As a result, at least a part of the crush of the energy absorbing member 100 that has been destroyed by the inner winding is discharged from the inside of the energy absorbing member 100 to the outside through the opening 502. Therefore, the crushed debris of the energy absorbing member 100 destroyed by the inner winding is less likely to be clogged inside the energy absorbing member 100, and the remaining crushed energy absorbing member 100 is reduced. Therefore, it is possible to prevent the crushing stroke amount of the energy absorbing member 100 from decreasing, and to obtain a large energy absorption amount.

<3. Modification>
The energy absorbing structure 10 according to the embodiment of the present invention has been described above. Then, the structure of the energy absorption structure which concerns on each modification is demonstrated.

(3-1. First Modification)
FIG. 6 is a cross-sectional view showing an example of the energy absorbing structure 12 according to the first modification. In the 1st modification, compared with the above-mentioned embodiment, the shape of a cover member differs. Specifically, as illustrated in FIG. 6, in the energy absorbing structure 12 according to the first modification, the cover member 702 has a cross-sectional shape that expands from the front end side toward the rear end side.

  Thereby, the cross-section secondary moment in the cross section in the circumferential direction becomes smaller as the portion of the cover member 702 closer to the end on the front end side. Therefore, the bending rigidity becomes smaller as the portion of the cover member 702 closer to the end portion on the front end side. Therefore, when the collision load is input, the portion of the cover member 702 that is closer to the end on the front end side is more likely to buckle preferentially. Therefore, when the cover member 702 is crushed, it can be suppressed that a part of the cover member 702 remains without buckling. Therefore, it is possible to prevent a part of the axial compression deformation of the energy absorbing member 100 from being hindered. Therefore, it is possible to prevent the crushing stroke amount of the energy absorbing member 100 from being reduced and obtain a large energy absorption amount. Can do.

  Further, when the cover member 702 has a polygonal cross-sectional shape that expands from the front end side toward the rear end side, a collision load is input to the energy absorbing structure 12 from an oblique direction with respect to the vehicle front-rear direction. In addition, a part of the load can be easily applied to the wall surface of the cover member 702 having a small angle with the load input direction. Therefore, it is possible to suppress the posture of the energy absorbing structure 12 from being inclined when a vehicle collision occurs. Therefore, since the increase in the axial inclination of the energy absorbing member 100 with respect to the input direction of the collision load can be suppressed, a decrease in the ratio of the collision load spent on the axial compression deformation of the energy absorbing member 100 can be suppressed. obtain. Therefore, it is possible to suppress a decrease in the amount of energy absorption when the energy absorbing member 100 is crushed.

(3-2. Second Modification)
FIG. 7 is a cross-sectional view showing an example of the energy absorbing structure 14 according to the second modification. The second modification is different from the first modification in that the rib is close to the energy absorbing member 100. Specifically, as shown in FIG. 7, in the energy absorbing structure 14 according to the second modification, the rib 902 is close to the outer peripheral surface of the end portion on the rear end side of the energy absorbing member 100.

  When a collision load is input, the outer peripheral surface of the energy absorbing member 100 can be supported by the rib 902 when a force causing bending deformation is applied to the rear end portion of the energy absorbing member 100. Thereby, when the energy absorbing structure 10 is crushed, the posture of the energy absorbing member 100 can be suppressed from being inclined. Therefore, since the increase in the axial inclination of the energy absorbing member 100 with respect to the input direction of the collision load can be suppressed, a decrease in the ratio of the collision load spent on the axial compression deformation of the energy absorbing member 100 can be suppressed. obtain. Therefore, it is possible to suppress a decrease in the amount of energy absorption when the energy absorbing member 100 is crushed.

  A gap having a predetermined size is preferably provided between the rib 902 and the outer peripheral surface of the energy absorbing member 100. During normal times when no collision load is input to the vehicle, vibrations generated between the road surface and the wheels, vibrations generated from the inside of the vehicle, and the like can be transmitted to the energy absorbing structure 10. In order to suppress damage of the energy absorbing member 100 due to friction between the energy absorbing member 100 and the rib 902 due to such vibration, the size of the gap is appropriately set.

(3-3. Third Modification)
FIG. 8 is a cross-sectional view showing an example of the energy absorbing structure 16 according to the third modification. The third modification is different from the first modification in that a second rib is provided. When the rib 900 according to the above-described embodiment or the first modification is the first rib, the second rib is at least the inner peripheral surface side or the outer peripheral surface of the end portion on the rear end side of the energy absorbing member 100. It is provided on either one of the sides and extends in the axial direction of the energy absorbing member 100. Specifically, as shown in FIG. 8, in the energy absorbing structure 16 according to the third modification, the energy absorbing member 100 is disposed on the inner peripheral surface side of the rear end side of the energy absorbing member 100. A second rib 910 extending in the axial direction is provided. The second rib 910 is made of, for example, a metal material such as a steel material or aluminum, a resin, or the like, and is joined to the surface on the front end side of the holding member 500 by welding or an adhesive. Note that the second rib 910 may be formed integrally with the holding member 500. Further, the second rib 910 may extend from the rear end side end portion to the front end side end portion on the inner peripheral surface side of the energy absorbing member 100.

  When a collision load is input, the inner peripheral surface of the energy absorbing member 100 can be supported by the second rib 910 when a force causing bending deformation is applied to the rear end portion of the energy absorbing member 100. Thereby, when the energy absorbing structure 10 is crushed, the posture of the energy absorbing member 100 can be suppressed from being inclined. Therefore, since the increase in the axial inclination of the energy absorbing member 100 with respect to the input direction of the collision load can be suppressed, a decrease in the ratio of the collision load spent on the axial compression deformation of the energy absorbing member 100 can be suppressed. obtain. Therefore, it is possible to suppress a decrease in the amount of energy absorption when the energy absorbing member 100 is crushed.

  A gap having a predetermined size is preferably provided between the second rib 910 and the inner peripheral surface of the energy absorbing member 100. In order to suppress damage to the energy absorbing member 100 due to friction between the energy absorbing member 100 and the second rib 910 due to vibration that can be transmitted to the energy absorbing structure 10 in a normal time when a collision load is not input to the vehicle. In addition, the size of the gap is set as appropriate.

(3-4. Fourth Modification)
FIG. 9 is a cross-sectional view showing an example of the energy absorbing structure 18 according to the fourth modification. In the fourth modification, the arrangement of the second ribs is different from that in the third modification. Specifically, as shown in FIG. 9, in the energy absorbing structure 18 according to the fourth modification, the shaft of the energy absorbing member 100 is disposed on the outer peripheral surface side of the end portion on the rear end side of the energy absorbing member 100. A second rib 912 extending in the direction is provided. Note that the second rib 912 may be extended from the end on the rear end side to the end on the front end side on the outer peripheral surface side of the energy absorbing member 100.

  When a collision load is input, if a force causing bending deformation is applied to the rear end portion of the energy absorbing member 100, the outer peripheral surface of the energy absorbing member 100 can be supported by the second rib 912. Thereby, when the energy absorbing structure 10 is crushed, the posture of the energy absorbing member 100 can be suppressed from being inclined. Therefore, since the increase in the axial inclination of the energy absorbing member 100 with respect to the input direction of the collision load can be suppressed, a decrease in the ratio of the collision load spent on the axial compression deformation of the energy absorbing member 100 can be suppressed. obtain. Therefore, it is possible to suppress a decrease in the amount of energy absorption when the energy absorbing member 100 is crushed.

  A gap having a predetermined size is preferably provided between the second rib 912 and the outer peripheral surface of the energy absorbing member 100. In order to suppress damage of the energy absorbing member 100 due to friction between the energy absorbing member 100 and the second rib 912 due to vibration that can be transmitted to the energy absorbing structure 10 at a normal time when a collision load is not input to the vehicle. In addition, the size of the gap is set as appropriate.

  In the second to fourth modifications, the cover member 702 has an example having a cross-sectional shape that expands from the front end side toward the rear end side, but the shape of the cover member 702 is limited to the example. Not.

  In the third modification and the fourth modification, the second rib is provided on either the inner peripheral surface side or the outer peripheral surface side of the end portion on the rear end side of the energy absorbing member 100. Although demonstrated, the 2nd rib may be provided in both the inner peripheral surface side and the outer peripheral surface side of the edge part of the rear end side of the energy absorption member 100. FIG.

<4. Conclusion>
As described above, according to each embodiment of the present invention, the rib 900 is provided on the inner peripheral surface side of at least the rear end side of the cover member 700 and extends in the axial direction of the cover member 700. . Therefore, the bending rigidity of the end portion on the rear end side of the cover member 700 can be increased. Thereby, at the initial stage of the crushing process of the cover member 700 due to the input of the collision load, it is possible to prevent the bending deformation from occurring at the end portion on the rear end side of the cover member 700 before the entire cover member 700 is collapsed. . Therefore, when the energy absorbing structure 10 is crushed, the posture of the energy absorbing structure 10 can be suppressed from being inclined. Therefore, since the increase in the axial inclination of the energy absorbing member 100 with respect to the input direction of the collision load can be suppressed, a decrease in the ratio of the collision load spent on the axial compression deformation of the energy absorbing member 100 can be suppressed. obtain. Therefore, it is possible to suppress a decrease in the amount of energy absorption when the energy absorbing member 100 is crushed.

  In addition, according to an embodiment, the cover member 700 may have a polygonal cross section. As a result, corner portions that are likely to bear a load are provided in the cover member 700, so that it is possible to increase the amount of energy absorbed when the cover member 700 is crushed when a collision load is input.

  According to an embodiment, the opening 502 is provided in the center of the holding member 500 that holds the rear end side of the energy absorbing member 100. As a result, at least a part of the crush of the energy absorbing member 100 that has been destroyed by the inner winding is discharged from the inside of the energy absorbing member 100 to the outside through the opening 502. Therefore, the crushed debris of the energy absorbing member 100 destroyed by the inner winding is less likely to be clogged inside the energy absorbing member 100, and the remaining crushed energy absorbing member 100 is reduced. Therefore, it is possible to prevent the crushing stroke amount of the energy absorbing member 100 from decreasing, and to obtain a large energy absorption amount.

  Moreover, according to a certain modification, the cover member 702 has a cross-sectional shape that expands from the front end side toward the rear end side. Thereby, the cross-section secondary moment in the cross section in the circumferential direction becomes smaller as the portion of the cover member 702 closer to the end on the front end side. Therefore, the bending rigidity becomes smaller as the portion of the cover member 702 closer to the end portion on the front end side. Therefore, when the collision load is input, the portion of the cover member 702 that is closer to the end on the front end side is more likely to buckle preferentially. Therefore, when the cover member 702 is crushed, it can be suppressed that a part of the cover member 702 remains without buckling. Therefore, it is possible to prevent a part of the axial compression deformation of the energy absorbing member 100 from being hindered. Therefore, it is possible to prevent the crushing stroke amount of the energy absorbing member 100 from being reduced and obtain a large energy absorption amount. Can do.

  According to a certain modification, the rib 902 is close to the outer peripheral surface of the end portion on the rear end side of the energy absorbing member 100. Therefore, the outer peripheral surface of the energy absorbing member 100 can be supported by the rib 902 when a force causing bending deformation is applied to the rear end portion of the energy absorbing member 100 when a collision load is input. Thereby, when the energy absorbing structure 10 is crushed, the posture of the energy absorbing member 100 can be suppressed from being inclined. Therefore, since the increase in the axial inclination of the energy absorbing member 100 with respect to the input direction of the collision load can be suppressed, a decrease in the ratio of the collision load spent on the axial compression deformation of the energy absorbing member 100 can be suppressed. obtain. Therefore, it is possible to suppress a decrease in the amount of energy absorption when the energy absorbing member 100 is crushed.

  Further, according to a modification, at least one of the end portion on the rear end side of the energy absorbing member 100 on the inner peripheral surface side or the outer peripheral surface side is extended in the axial direction of the energy absorbing member 100. Ribs are provided. Therefore, when a force that causes bending deformation is applied to the rear end portion of the energy absorbing member 100 when a collision load is input, the inner or outer peripheral surface of the energy absorbing member 100 is supported by the second rib. be able to. Thereby, when the energy absorbing structure 10 is crushed, the posture of the energy absorbing member 100 can be suppressed from being inclined. Therefore, since the increase in the axial inclination of the energy absorbing member 100 with respect to the input direction of the collision load can be suppressed, a decrease in the ratio of the collision load spent on the axial compression deformation of the energy absorbing member 100 can be suppressed. obtain. Therefore, it is possible to suppress a decrease in the amount of energy absorption when the energy absorbing member 100 is crushed.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention belongs can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

  In the above description, the example in which the energy absorbing structure is disposed between the front bumper beam and the front frame has been described. However, the energy absorbing structure may be provided at the rear of the vehicle, for example, the rear bumper beam. It is arranged between the rear frame and the rear frame, and can absorb the collision energy by receiving a collision load from the rear of the vehicle.

10, 12, 14, 16, 18 Energy absorbing structure 30 Front bumper beam 50 Front frame 100 Energy absorbing member 102 Reduced diameter portion 300 Fixed member 500 Holding member 502 Opening portion 700, 702 Cover member 900, 902 Rib 910, 912 First 2 ribs

Claims (6)

A cylindrical energy absorbing member made of fiber reinforced resin that crushes in the axial direction when absorbing a collision load and absorbs collision energy;
A cylindrical cover member that covers the outer peripheral surface of the energy absorbing member and is crushed in the axial direction when the collision load is input;
Wherein the input side of the front SL collision load of the cover member provided on the inner peripheral surface side of the opposite end, extending in the axial direction of said cover member from said end portion over a portion of the length of said cover member Existing ribs,
An energy absorbing structure comprising:   A cylindrical energy absorbing member made of fiber reinforced resin that crushes in the axial direction when absorbing a collision load and absorbs collision energy;
  A cylindrical cover member that covers the outer peripheral surface of the energy absorbing member and is crushed in the axial direction when the collision load is input;
  A rib provided on an inner peripheral surface side of an end portion of the cover member opposite to the input side of the collision load, and extending in the axial direction of the cover member;
  With
  The said rib is an energy absorption structure which adjoins to the outer peripheral surface of the edge part on the opposite side to the said input side of the said energy absorption member. A cylindrical energy absorbing member made of fiber reinforced resin that crushes in the axial direction when absorbing a collision load and absorbs collision energy;
  A cylindrical cover member that covers the outer peripheral surface of the energy absorbing member and is crushed in the axial direction when the collision load is input;
  A first rib provided on an inner peripheral surface side of an end portion of the cover member opposite to the input side of the collision load, and extending in an axial direction of the cover member;
  With
  A second rib extending in the axial direction of the energy absorbing member is provided on at least one of the inner peripheral surface side and the outer peripheral surface side of the end of the energy absorbing member opposite to the input side. , Energy absorbing structure. The energy absorbing structure according to any one of claims 1 to 3, wherein the cover member has a cross-sectional shape that expands from the input side of the collision load toward the side opposite to the input side. The energy absorption structure according to any one of claims 1 to 4 , wherein a cross section of the cover member is a polygon. A holding member that holds an end of the energy absorbing member opposite to the input side of the collision load;
The holding member is provided with an opening at a position corresponding to the internal space of the energy absorbing member.
The energy absorption structure as described in any one of Claims 1-5.

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