JP6997698B2 - Vehicle load bearing structure - Google Patents

Description

The present invention relates to a load-bearing structure such as a side sill of a vehicle.

The side sill arranged below the side of the vehicle is coupled to the ends of a plurality of cross members arranged along the vehicle width direction. In a vehicle having such a structure, when a load is input to the side sill from an object outside the vehicle, the input load is transmitted from the side sill to a plurality of cross members, and the energy of the input load is absorbed by the deformation of the side sill.

The above-mentioned load-bearing structure is a structure in which a load-bearing member (side sill) having a hollow structure is coupled to a plurality of load-bearing members (cross members). In this type of load-bearing structure, it is desired that the load-bearing member does not excessively deform at an early stage when a load is input to the load-bearing member from an external object. As a countermeasure against this, there is a method in which the wall of a load receiving member having a hollow structure is reinforced with a reinforcing member such as a fiber reinforced resin (see, for example, Patent Document 1).

European Patent No. 2427362

However, in the load support structure in which the wall of the load receiving member is reinforced with the reinforcing member, the maximum load capacity of the load receiving member increases, but if the input load from an object outside the vehicle exceeds the maximum load capacity at an early stage, then There is a concern that the energy absorption effect will drop sharply.

Therefore, the present invention is intended to provide a load-bearing structure for a vehicle that can obtain a large energy absorption effect in the latter stage of the relative movement when the relative movement between the vehicle and an external object in the close direction progresses. be.

The load-bearing structure of the vehicle according to the present invention adopts the following configuration in order to solve the above problems.
That is, the load-bearing structure of the vehicle according to the present invention extends in a direction intersecting the extension direction of the load-bearing member having a hollow structure (for example, the side sill 2 of the embodiment) extending in one direction of the vehicle. A load supporting member (for example, the cross member 4 of the embodiment) coupled to a plurality of locations separated in the extending direction of the load receiving member is provided, and a plurality of loads input from the outside of the vehicle of the load receiving member are applied. In the load-bearing structure of a vehicle supported by the load-bearing member, the load-bearing member is made of a fiber reinforcing resin, and the outer wall of the load-bearing member (for example, the side sill outer 2A of the embodiment) is bent. A bending reinforcing member (for example, the bending reinforcing member 12 of the embodiment) for increasing the strength is provided, and an energy absorbing member (for example, an energy absorbing member (for example) is provided in the load transmission path from the wall portion on the outside of the vehicle including the bending reinforcing member to each of the load supporting members. For example, the plate-shaped structure 13) of the embodiment is provided, and the total load capacity of the adjacent energy absorbing members is set to be smaller than the load capacity for bending of the outer wall portion of the vehicle including the bending reinforcing member . The load-bearing member is provided with a space portion on the outside of the vehicle (for example, the space portion 10 of the embodiment) by means of a partition wall (for example, the stiffener 2C of the embodiment) arranged in a cross section substantially orthogonal to the extending direction of the load-bearing member. It is partitioned into a space portion inside the vehicle (for example, the space portion 11 of the embodiment), the bending reinforcing member is joined to the wall outside the vehicle inside the space portion outside the vehicle, and the energy absorbing member is joined to the wall outside the vehicle. The same number as the load-bearing members are arranged in the space inside the vehicle at positions corresponding to the load-bearing members, and the partition wall and the inner surface of the inner wall of the load-bearing member are in contact with each other to support the load. The member is characterized in that it is coupled to the outer surface of the inner wall of the load receiving member .

In the above configuration, when a load is input from the external object to the load receiving member due to the relative movement of the vehicle and the external object in the proximity direction, the energy absorbing member starts to be deformed first, and the energy absorbing member When the deformation of the load receiving member has progressed to some extent, the bending deformation of the wall portion (including the bending reinforcing member) on the outer side of the vehicle of the load receiving member starts. As a result, in the first half of the relative movement, the energy absorbing member absorbs the energy of the input load, and in the second half of the relative movement, the wall on the outside of the vehicle including the bending reinforcing member mainly absorbs the energy of the input load. It will be.

Further, in the load supporting structure of the vehicle according to the present invention, the bending reinforcing member is made of a fiber reinforcing resin.
Therefore, the bending strength of the load receiving member can be efficiently increased while the structure is lightweight and has good moldability.

Further, in the load-bearing structure of the vehicle according to the present invention, the load- bearing member has a space outside the vehicle and a space inside the vehicle by means of a partition wall arranged in a cross section substantially orthogonal to the extending direction of the load-bearing member. The bending reinforcing member is joined to the wall outside the vehicle inside the space inside the vehicle, and the energy absorbing member is arranged in the space inside the vehicle .
With this configuration, the reinforcing function portion of the wall outside the vehicle by the bending reinforcing member and the energy absorbing function portion by the energy absorbing member are collectively arranged inside the load receiving member. Therefore, by adopting this configuration, it is possible to make the load support structure compact and improve the appearance.

Further, in the load-bearing structure of the vehicle according to the present invention, the energy absorbing member abuts on the partition wall and the inner surface of the inner wall of the load-bearing member, and the load-bearing member is the inner wall of the load-bearing member. It is bonded to the outer surface .
In this case, since the energy absorbing member is arranged in series between the partition wall in the load receiving member and the load supporting member, the energy absorbing member can be efficiently deformed when a load is input from the outside of the vehicle body. Therefore, by adopting this configuration, it is possible to reliably execute the first stage energy absorption by the energy absorbing member and the second stage energy absorption by the vehicle outer wall portion of the load receiving member.

The wall on the outside of the vehicle or the bending reinforcing member may be provided with a protrusion (for example, the protrusion 12b of the embodiment) protruding toward the central region of the partition wall.
In this case, when the load is input from the outside, the load can be efficiently transmitted to the central region of the energy absorbing member by the protrusion.

According to the present invention, when a load is input to the load receiving member from the outside, the energy absorbing member is deformed as the first step, and then the outer wall of the load receiving member including the bending reinforcing member is used as the second step. Since it is deformed, it is possible to prevent the wall portion on the outside of the vehicle from being excessively bent and deformed in the first half of the relative movement when the relative movement of the vehicle and the external object in the proximity direction progresses. Therefore, according to the present invention, a large energy absorption effect can be obtained in the later stage of the relative movement.

It is a perspective view which shows the skeleton part of the vehicle of an embodiment. It is a perspective view which shows the load support structure of an embodiment. FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 2 of the load-bearing structure of the embodiment. It is explanatory drawing which shows typically the deformation behavior of the load support structure of embodiment. It is a load-displacement characteristic diagram of a load support structure of an embodiment and a comparative example.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the arrow FR points to the front of the vehicle, the arrow UP points to the upper part of the vehicle, and the arrow LH points to the left side of the vehicle.

FIG. 1 is a view of the skeleton portion of the vehicle 1 of the present embodiment as viewed from diagonally above the rear left.
In the vehicle 1 of the present embodiment, a pair of side sills 2 extending substantially along the front-rear direction of the vehicle body are arranged below the left and right side portions of the vehicle body. Floor panels 3 are erected on the left and right side sills 2. Further, on the upper surface side and the lower surface side of the floor panel 3, a plurality of cross members 4 extending substantially along the vehicle width direction and having both ends connected to the left and right side sills 2 are arranged. The cross member 4 extends in a direction intersecting the side sill 2 and is coupled to a plurality of positions separated in the extending direction of the side sill 2. Reference numeral 5 in FIG. 1 is a driver's seat side seat and a passenger seat side seats arranged in the vehicle interior.
The load-bearing structure of the present embodiment is composed of a side sill 2 and a cross member 4 as main elements. In the present embodiment, the side sill 2 constitutes a load receiving member, and the cross member 4 constitutes a load supporting member.

FIG. 2 is a perspective view showing a joint portion between the side sill 2 and the cross member 4, and FIG. 3 is a cross-sectional view taken along the line III-III of FIG.
As shown in FIGS. 2 and 3, in the side sill 2, the side sill outer 2A having a substantially hat-shaped cross section and the side sill inner 2B are joined to each other with a flat plate-shaped stiffener 2C interposed therebetween. The side sill 2 has a hollow structure so as to substantially follow the front-rear direction of the vehicle body. Further, the inside of the side sill 2 is separated into a space portion 10 on the outside of the vehicle and a space portion 11 on the inside of the vehicle by a stiffener 2C that is vertically erected.
In the present embodiment, the side sill outer 2A constitutes the vehicle outer wall of the load receiving member, and the side sill inner 2B constitutes the vehicle inner wall of the load receiving member. Further, the stiffener 2C constitutes a partition wall.

The side sill outer 2A connects the upper and lower joining flanges 2Af joined to the stiffener 2C and the side sill inner 2B, the outer wall 2Ao arranged vertically at the outermost position of the vehicle, and the outer wall 2Ao and the upper and lower joining flanges 2Af. It has an upper wall 2Au and a lower wall 2Al.

Further, the side sill inner 2B includes upper and lower joining flanges 2Bf joined to the stiffener 2C and the side sill outer 2A, an inner wall 2Bi vertically arranged at the innermost position of the vehicle, and the inner wall 2Bi and the upper and lower joining flanges 2Bf. It has an upper wall 2Bu and a lower wall 2Bl to connect to.

A bending reinforcing member 12 for increasing the bending strength of the wall of the side sill outer 2A is joined to the inner surface of the side sill outer 2A facing the space 10 on the outer side of the vehicle. The bending reinforcing member 12 is formed of a material having a higher bending strength than the side sill outer 2A made of a steel material or the like. In this embodiment, a fiber reinforced resin such as CFRP (Carbon Fiber Reinforced Plastics) is used as the bending reinforcing member 12.

The bending reinforcing member 12 is bonded to a range extending over the upper region of the upper wall 2Au and the outer wall 2Ao of the side sill outer 2A and a range extending over the lower wall 2Al of the side sill outer 2A and the lower region of the outer wall 2Ao by adhesion or the like. The bending reinforcing member 12 has a base portion 12a joined to the side sill outer 2A, and a protrusion 12b protruding from the base portion 12a toward a substantially central region in the vertical direction of the stiffener 2C. In the case of the present embodiment, the bending reinforcing member 12 is formed in a substantially M-shaped cross section as shown in FIG. The end surface of the protrusion 12b of the bending reinforcing member 12 is in contact with the central region of the vehicle outer surface of the stiffener 2C.

The ends of the cross member 4 are joined to the outer surfaces of the upper wall 2Bu, the lower wall 2Bl, and the inner wall 2Bi of the side silina 2B by welding or the like. Further, a plate-shaped structure 13 having a substantially U-shaped cross section or a box-shaped cross section is joined to an extension position in the extending direction of the cross member 4 in the inside of the side sill inner 2B. The plate-shaped structure 13 is made of a metal material such as a steel material, and the end surface on the outer side of the vehicle is in contact with the inner surface of the stiffener 2C. The plate-shaped structure 13 may be welded to the inner surface of the stiffener 2C.
In the present embodiment, the plate-shaped structure 13 constitutes an energy absorbing member.

Here, inside the side sill inner 2B, the same number of plate-shaped structures 13 as the cross members 4 to be coupled are attached at positions corresponding to the cross members 4. The total load capacity of the two plate-shaped structures 13 adjacent to each other inside the side sill inner 2B (the total load capacity of the two plate-shaped structures 13) is the bending of the side sill outer 2A including the bending reinforcing member 12 (the total load capacity). It is set smaller than the load capacity for bending in the horizontal direction. That is, when a large load is input from the outside to the region of the side sill 2 between the position where one plate-shaped structure 13 is arranged and the position where the plate-shaped structure 13 adjacent to the side sill 2 is arranged. In addition, the two plate-shaped structures 13 are set to start deformation prior to the start of bending deformation of the side sill outer 2A.

FIG. 4 is a schematic explanatory view showing the deformation behavior of the side sill 2 when the side sill 2 receives a load from the outside in the order of (A), (B), and (C). Reference numeral 50 in FIG. 4 is an external object moving toward the side sill 2. Further, FIG. 5 is a characteristic diagram showing the relationship between the displacement of the side sill 2 to the inside of the vehicle when the side sill 2 receives a load from the outside and the load received by the side sill 2. In addition, A in FIG. 5 shows the characteristic of this embodiment, and B shows the characteristic of the load support structure of the comparative example which does not have a plate-like structure 13 (energy absorption member).
As shown in FIG. 4A, when the object 50 approaches the side sill 2, the object 50 first comes into contact with the vehicle outer surface of the side sill outer 2A. At this time, a load in the compression direction acts on the side sill outer 2A in the longitudinal direction, and a load in the extension direction acts on the side sill inner 2B in the longitudinal direction.

In this way, as the load input from the object 50 progresses, the elastic deformation of the plate-like structure 13 progresses until the displacement position of P1 in FIG. 5 is reached, and when the displacement position of P1 in FIG. 5 is reached, the figure shows. As shown in 4 (B), the plate-shaped structure 13 starts plastic deformation (crush deformation). The plastic deformation of the plate-shaped structure 13 continues until the displacement position of P2 in FIG. 5 is reached.

Then, when the load input from the object 50 further progresses from this state, the side sill outer 2A reinforced by the bending reinforcing member 12 starts bending deformation as shown in FIG. 4C. When the bending deformation of the side sill outer 2A is started, the reaction force (load) of the side sill outer 2A increases as the displacement progresses. The increase in the reaction force (load) of the side sill outer 2A continues until the input load reaches the maximum withstand load (peak point in FIG. 5) of the side sill outer 2A.

As is clear from FIG. 5, in the comparative example of the characteristic B, the load acting on the side sill outer 2A in the displacement range between the positions P1 and P2 is the maximum load capacity (peak point), but the structure of the present embodiment. Then, the load acting on the side sill outer 2A in the displacement range beyond the position P2 becomes the maximum load capacity (peak point). Therefore, when the structure of the present embodiment is adopted, a large energy absorption effect can be obtained in a displacement range exceeding the position P2.

As described above, in the load support structure of the present embodiment, when a load is input to the side sill 2 (load receiving member) from the outside, the plate-shaped structure 13 which is an energy absorbing member is deformed as the first stage. After that, the side sill outer 2A reinforced by the bending reinforcing member 12 is deformed as the second step. Therefore, when the relative movement of the vehicle and the external object in the close direction progresses, it is possible to prevent the side sill outer 2A from being excessively bent and deformed in the previous period of the relative movement. Therefore, when the load-bearing structure of the present embodiment is adopted, a large energy absorption effect can be obtained in the later stage of the relative movement of the vehicle and the external object in the close direction.

In particular, in the load supporting structure of the present embodiment, since the fiber reinforcing resin is used as the bending reinforcing member 12, the bending reinforcing member 12 is lightweight and has a structure with good moldability, but the side sill outer 2A is bent. The strength can be increased efficiently.

Further, in the load support structure of the present embodiment, the inside of the side sill 2 is divided into a space portion 10 on the outside of the vehicle and a space portion 11 on the inside of the vehicle by a stiffener 2C (partition partition), and the bending reinforcing member 12 is a space on the outside of the vehicle. It is joined to the side sill outer 2A in the portion 10, and the plate-shaped structure 13 is arranged in the space portion 11 inside the vehicle. Therefore, the reinforcing function portion of the side sill outer 2A by the bending reinforcing member 12 and the energy absorbing function portion of the plate-shaped structure 13 are collectively arranged inside the side sill 2. Therefore, when the configuration of the present embodiment is adopted, the load supporting structure can be made compact and the appearance can be prevented from being deteriorated.

Further, in the load-bearing structure of the present embodiment, the plate-shaped structure 13 is in contact with the stiffener 2C and the inner surface of the side sill inner 2B, and the cross member 4 is coupled to the outer surface of the side sill inner 2B. Therefore, the plate-shaped structure 13 which is an energy absorbing member is arranged in series between the stiffener 2C and the cross member 4, and as a result, the plate-shaped structure 13 can be efficiently deformed at the time of load input. Therefore, when the configuration of the present embodiment is adopted, the energy absorption of the first stage by the plate-shaped structure 13 and the energy absorption of the second stage by the reinforced side sill outer 2A can be surely executed.

Further, in the load support structure of the present embodiment, since the protrusion 12b projecting toward the central region of the stiffener 2C is provided in the bending reinforcing member 12, the protrusion 12b causes the plate-like structure 13 to have a protrusion 12b. The load can be efficiently transmitted to the central region. The protrusion can also be formed on the side sill outer 2A. However, when the bending reinforcing member 12 is provided as in the present embodiment, the protrusion 12b can be easily formed and the load can be transmitted to the central region of the plate-shaped structure 13 with high rigidity.

The present invention is not limited to the above embodiment, and various design changes can be made without departing from the gist thereof. For example, in the above embodiment, the load-bearing structure of the present invention is adopted for the connecting portion between the side sill and the cross member, but the load-bearing structure of the present invention is the connecting portion between the front and rear side members and the bumper beam and the like. , Can also be applied to other parts of the vehicle.

1 ... Vehicle 2 ... Side sill (load receiving member)
2A ... Side sill outer (wall on the outside of the car)
2B ... Side sill inner (wall inside the car)
2C ... Stifuna (partition wall)
4 ... Cross member (load support member)
12 ... Bending reinforcement member 12b ... Protrusion 13 ... Plate-shaped structure (energy absorbing member)

Claims (2)

A hollow structure load receiving member that extends in one direction of the vehicle,
A load-bearing member that extends in a direction intersecting the extension direction of the load-bearing member and is coupled to a plurality of locations separated in the extension direction of the load-bearing member.
In a vehicle load support structure in which a load input from the outside of the vehicle of the load receiving member is supported by the plurality of load support members.
The load receiving member is made of a fiber reinforced resin, and is provided with a bending reinforcing member that enhances the bending strength of the outer wall of the load receiving member.
An energy absorbing member is provided in the load transmission path from the wall portion on the outer side of the vehicle including the bending reinforcing member to each of the load supporting members.
The total load capacity of the adjacent energy absorbing members is set to be smaller than the load capacity for bending the outer wall portion of the vehicle including the bending reinforcing member .
The load receiving member is divided into a space outside the vehicle and a space inside the vehicle by a partition wall arranged in a cross section substantially orthogonal to the extending direction of the load receiving member.
The bending reinforcing member is joined to the wall on the outside of the vehicle inside the space on the outside of the vehicle.
The energy absorbing member is arranged in the space inside the vehicle in the same number as the load supporting member at a position corresponding to the load supporting member, and on the partition wall and the inner surface of the inner wall of the load receiving member. Abut and
The load-bearing member is a load-bearing structure for a vehicle, characterized in that the load-bearing member is coupled to an outer surface of a wall inside the vehicle of the load-bearing member. The load-bearing structure for a vehicle according to claim 1 , wherein the wall on the outer side of the vehicle or the bending reinforcing member is provided with a protrusion protruding toward the central region of the partition wall.

Images