JP3985657B2 - Body front structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle body front structure.
[0002]
[Prior art]
Conventionally, a vehicle body front structure in which a vehicle body rear end portion of a pair of left and right front side members constituting a front skeleton of a vehicle body is bent diagonally rearward and the respective rear terminals are coupled to corresponding left and right side sills, respectively. (For example, refer to Patent Document 1).
[0003]
Therefore, in such a vehicle body front structure, when a load is input from the front of the vehicle body, the input load is transmitted from the front side member to the side sill via the vehicle body rear end.
[0004]
[Patent Document 1]
JP 2001-287664 A (pages 3, 4 and 1)
[0005]
[Problems to be solved by the invention]
However, in such a conventional vehicle body front structure, when the input load from the front is large, the load transmitted from the front side member to the side sill also increases, so the amount of deformation of the side sill to the outside of the vehicle increases. There is a risk that the load input from the front side member cannot be sufficiently supported.
[0006]
Therefore, the present invention provides a vehicle body front structure that can effectively reduce the deformation of the side sill when an excessive load is input to the front side member from the front and transmitted to the side sill.
[0007]
[Means for Solving the Problems]
In the present invention, the vehicle body rear end portion of the front side member is inclined downward, and the vehicle body rear end portion is coupled to the vehicle body front end portion of the side sill via the first connection member, and the second connection member. The first sill portion of the side sill is coupled to the rear of the vehicle body rather than the coupling portion of the first sill connecting member of the side sill. While being set to a position offset to any one of the lower sides, the second coupling portion between the second connecting member and the side sill is set to a position offset in the opposite direction to the first coupling site.
[0008]
【The invention's effect】
According to the present invention, the load input from the front is transmitted from the front side member to the side sill via the first connecting member and the second connecting member.
[0009]
At this time, the first coupling site between the first coupling member and the side sill is set at a position offset to either above or below the side sill, and the second coupling site between the second coupling member and the side sill is Since the first binding site is set at a position offset in the upside down direction, the side sill can cause the first binding site and the second binding site to generate moments in opposite directions to cancel each other. As a result, the side sill can prevent or reduce torsional deformation about the axis in the longitudinal direction of the vehicle body, and thus can suppress cabin deformation.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0011]
1 to 9 show a first embodiment of a vehicle body front structure according to the present invention, FIG. 1 is a plan view showing the skeleton structure of the vehicle body, FIG. 2 is a side view showing the skeleton structure of the vehicle body, and FIG. FIG. 4 is an exploded cross-sectional view taken along line AA in FIG. 1, and FIG. 5 is an enlarged cross-sectional view taken along line BB in FIG. 6 is a perspective view showing the main part of the lower member constituting the front side member, FIG. 7 is a plan view of the main part showing the skeleton structure on the left side of the front part of the vehicle body, and FIG. 8 is a perspective view of the left side of the vehicle body showing the moment acting on the side sill. FIG. 9 is a plan view of the main part of the vehicle body skeleton showing the load transmission path at the time of a side collision.
[0012]
The vehicle body front structure of the first embodiment is a pair of left and right fronts that are located on both sides of the front compartments F and C of the vehicle body and extend in the vehicle front-rear direction as shown in FIGS. A side member 10 is provided, and a pair of left and right side sills 20 extending in the longitudinal direction of the vehicle body are provided on both sides in the vehicle width direction of the floor panel Pf that separates the lower surface of the cabin C.
[0013]
The front side member 10 is configured by a member front portion 10A that absorbs energy by collision of a collision load F inputted from the front by axial crushing, and a member rear portion 10B that absorbs energy of the collision load F by bending deformation. The rear end portion of each front side member 10 (the rear end portion is the same as the rear end portion of the vehicle body), as shown in FIGS. Inclined.
[0014]
Between the front ends of the pair of left and right front side members 10 (the front end is the same as the front end of the vehicle body), a bumper reinforcement 11 that forms the skeleton of the front bumper as shown in FIG. The collision load F from the front is input to the front side member 10 via the bumper reinforcement 11 and the bumper stay 11a.
[0015]
The rear end portion of the front side member 10 that is inclined downward is coupled to the front end portion of the side sill 20 via an outrigger (torque box) 12 that is inclined to the outside of the vehicle as a first connecting member. It is connected to the rear side of the vehicle body from the connecting part (first connecting part K1) of the outrigger 12 of the side sill 20 through the extension member 13 inclined from the rear end as a second connecting member extending from the rear end. 2 binding sites K2).
[0016]
Between the left and right side sills 20, a second cross member 21, a third cross member 22, and a rear cross member 23 are spanned from the extension member 13 toward the rear of the vehicle body at appropriate intervals. The rear end of the side sill 20 is a rear side member. 24.
[0017]
As shown in FIG. 2, the front ends of the left and right side sills 20 rise upward, the center pillar 26 is connected to the center pillar 26, and the rear end is connected to the rear pillar (not shown). A front pillar upper 27 forming a roof side skeleton is provided between the upper ends.
[0018]
A pair of left and right reinforcing members 28 extending in the longitudinal direction of the vehicle body are provided on both sides of the tunnel portion T provided in the vehicle width direction center portion of the floor panel Pf.
[0019]
The front side member 10 has a lower member 10C in which a member rear portion 10B has a U-shaped cross section formed by press forming a steel plate as shown in FIG. 6, and a lower member 10C as shown in FIGS. The upper member 10D that closes the upper opening portion is formed in a closed cross section.
[0020]
At the upper end portion of the lower member 10C bent in a U-shaped cross section, the upper end portion is bent outward to form a flange portion f1, and the upper member 10D is joined by spot welding to the flange portion f1. is doing.
[0021]
The front side member 10 integrally forms an outrigger 12 and an extension member 13 when the lower member 10C and the upper member 10D are formed. As shown in FIG. 6, the outrigger 12 is formed on the lower member 10C. The part 12A and the forming part 13A of the extension member 13 are integrally formed.
[0022]
Of course, the upper member 10D forms a closed portion along the shape of the upper opening portion of the forming portion 12A of the outrigger 12 and the forming portion 13A of the extension member 13, and the upper opening portions of these forming portions 12A and 13A. Is supposed to block.
[0023]
Here, in the first embodiment, as shown in FIGS. 2 and 3, the first coupling site K1 between the outrigger 12 and the side sill 20 is set at a position offset above the side sill 20, The second binding site K2 between the extension member 13 and the side sill 20 is set at a position offset in the upside down direction with respect to the first binding site K1, that is, at a position offset below the side sill 20.
[0024]
That is, as shown in FIG. 4, the outrigger 12 joins the flange portion f <b> 2 provided at the connecting end portion of the formation portion 12 </ b> A and the upper member 10 </ b> D across the inner side surface 20 a upper side and the upper side surface 20 b of the side sill 20. In addition, as shown in FIG. 5, the extension member 13 has a flange portion f3 provided at the connecting end portion of the forming portion 13A and the upper member 10D, straddling the lower side surface 20c and the lower side surface 20a of the side sill 20. Are connected.
[0025]
Further, as shown in FIG. 2, the upper side of the outrigger 12 near the branch portion D1 is connected to the front pillar 25 via a dash cross member 14 as a third connecting member at the rear end portion of the front side member 10. I support it.
[0026]
In this embodiment, a suspension member 15 for attaching a front suspension (not shown) is disposed below the front side member 10.
[0027]
The suspension member 15 includes left and right vertical members 15a and 15b extending substantially in the longitudinal direction of the vehicle body along the lower side of the pair of left and right front side members 10, and front end portions of the left and right vertical members 15a and 15b. And the front lateral member 15c and the rear lateral member 15d that connect the rear end portions, respectively, are formed in a substantially rectangular plane shape, and more specifically, the rear lateral member 15d is formed shorter than the front lateral member 15c. The suspension member 15 has a flat trapezoidal shape with a slightly narrower width at the rear of the vehicle.
[0028]
The front end portion of the suspension member 15 is connected to brackets 16 (see FIG. 3) that are suspended from both ends of the front side member 15 c below the front end portion of the front side member 10.
[0029]
On the other hand, as shown in FIGS. 1 and 3, the member connecting portions 17 are respectively provided at the rear end portions of the pair of left and right front side members 10, that is, inside the branch portion D <b> 2 of the extension member 13. Both ends of the rear transverse member 15d of the suspension member 15 are coupled to each other.
[0030]
As shown in FIG. 6, the member connecting portion 17 is formed by integrally pressing the lower member 10C with a forming portion 17A of the member connecting portion 17, and the upper member 10D has an upper open portion of the forming portion 17A. A closed portion is formed along the shape, and this closed portion is spot welded to a flange portion f1 provided in the upper open portion of the formed portion 17A and closed.
[0031]
As shown in FIG. 6, a mounting bolt B1 as a fastening member of the rear lateral member 15d is located in the upper open portion of the forming portion 17A of the member connecting portion 17 as shown in FIG. The support plate 17C supporting the reference is coupled.
[0032]
In the member connecting portion 17, an insertion hole B1h for the mounting bolt B1 is formed in the bottom portion of the forming portion 17A, the support plate 17C, and the upper member 10D.
[0033]
A vertical wall 17C1 is bent at the front side member 10 side of the support plate 17C, and a flange f4 formed around the vertical wall 17C1 is coupled to the inner wall 10C1 and the bottom surface 10C2 of the lower member 10C. It is.
[0034]
At this time, the vertical wall 17C1 is connected to the vertical wall 13A1 of the forming portion 13A of the extension member 13 through a flange f4 provided on the rear side of the vehicle body so as to be substantially flush with each other.
[0035]
With the above-described configuration, in the vehicle body front structure of the first embodiment, when a load F is input from the front by a frontal collision or the like as shown in FIGS. 1 and 2, the collision load F is as shown in FIG. First, an input is made to the bumper reinforcement 11 and then to the front side member 10 via the bumper stay 11a.
[0036]
The collision load Ff input to the front side member 10 is transmitted to the side sill 20 by being distributed to the outrigger 12 and the extension member 13 in the loads Ff1 and Ff2.
[0037]
At this time, the first coupling site K1 between the outrigger 12 and the side sill 20 is set at a position offset upward from the side sill 20, and the second coupling site K2 between the extension member 13 and the side sill 20 is disposed below the side sill 20. 4, a moment Ma is generated in the direction of twisting the upper part of the side sill 20 toward the outside of the vehicle as shown in FIG. At the joint portion K2, a moment Mb is generated in a direction in which the lower portion of the side sill 20 is twisted outward.
[0038]
Therefore, this will be explained by a perspective view from the front of the vehicle body as shown in FIG. 8. The side sill 20 has a torsion beam whose back is fixed by a second cross member 21, a third cross member 22, a rear cross member 23 and a center pillar 26. Since the rear portion of the side sill 20 is securely supported, when the moment Ma is applied to the first binding site K1 and the moment Mb is applied to the second binding site K2, the moments Ma and Mb are Since the respective sides cancel each other in opposite directions, the side sill 20 can prevent or reduce torsional deformation about the axis in the longitudinal direction of the vehicle body, and thus can suppress deformation of the cabin C.
[0039]
Further, in this embodiment, when the vehicle body 1 is viewed from the side as shown in FIG. 3, the upper side of the front side member 10 near the branch portion D <b> 1 of the outrigger 12 is interposed via the dash cross member 14. Since it is connected to the front pillar 25, an input Ff acting on the front side member 10 generates a moment Mf in which the upper side where the dash cross member 14 is coupled is deformed rearward. The first coupling site K1, that is, the front end of the side sill 20, receives a moment Mf1 that deforms upward.
[0040]
However, since the rear input Ff2 acts on the lower portion of the side sill 20 due to the vehicle body side input to the extension member 13, a moment Mf2 that cancels the moment Mf1 is generated at the second coupling portion K2, and this moment Mf2 is transmitted to the outrigger 12. Therefore, the front side member 10 can be prevented from being deformed rearward at the connecting portion of the dash cross member 14 by inputting to the branch portion D1.
[0041]
Therefore, in the first embodiment, by suppressing the torsional deformation of the side sill 20 and the backward deformation of the connecting portion of the dash cross member 14, it is possible to suppress the reinforcement of the side sill 20 and the front side member 10 and increase the plate thickness. An increase in the weight of the vehicle body can be suppressed.
[0042]
Furthermore, in this embodiment, as shown in FIG. 1, member connecting portions 17 are provided at the rear ends of the pair of left and right front side members 10 inside the branch portion D2 of the extension member 13, Since both end portions of the rear lateral member 15d of the suspension member 15 are coupled to these member connecting portions 17, a load F 'is input to the side sill 20 through a door or pillar outside the figure as shown in FIG. In this case, a part of the load F ′ is input to the side sill 20 on the non-collision side (the vehicle body right side) via the second cross member 21 and the third cross member 22, while a part of the remaining load F ′ is input on the collision side ( The load is input to the extension member 13 on the left side of the vehicle body.
[0043]
The load fs input to the extension member 13 is transmitted to the member connecting portion 17 connected thereto, and the longitudinal component force fs2 along the left longitudinal member 15a of the suspension member 15 and the transverse component force fs1 along the rear transverse member 15d. And generate.
[0044]
The vertical component force fs2 is transmitted to the front end of the front side member 10 on the left side of the vehicle body from the front bracket 16 through the left vertical member 15a, and the lateral component force fs1 is transmitted to the non-collision side through the rear lateral member 15d. The signal is input to the member connecting portion 17 on the (right side of the vehicle body) and further transmitted from the extension member 13 on the non-collision side to the side sill 20 on the right side of the vehicle body.
[0045]
For this reason, since the side impact load F ′ can be distributed over a wide range of the vehicle body skeleton, it is possible to suppress reinforcement of the reinforcing members 28, the side sills 20, the front side members 10 and the like on both sides of the tunnel portion T, and an increase in plate thickness. As a result, an increase in the weight of the vehicle body can be suppressed.
[0046]
Furthermore, in this embodiment, as shown in FIG. 6, the member rear portion 10B of the front side member 10 is formed by pressing a steel plate integrally with the outrigger 12, the extension member 13, and the member connecting portion 17, The vertical wall 17C1 of the support plate 17C coupled to the upper open portion of the forming portion 17A of the member connecting portion 17 is connected to the vertical wall 13A1 of the forming portion 13A of the extension member 13 via a flange f4 provided on the rear side of the vehicle body. Therefore, the load fs (see FIG. 9) input to the extension member 13 at the time of a side collision is applied to the support plate 17C and eventually the member connecting portion 17 by the in-plane force of the vertical wall 13A1 of the extension member 13. It can be transmitted reliably.
[0047]
Therefore, the reinforcement of the member rear portion 10B and the increase in the plate thickness of the steel plate forming the member rear portion 10B can be suppressed, and the increase in the weight of the vehicle body can be further suppressed.
[0048]
By the way, in the first embodiment, the first binding site K1 is set at a position offset from the side sill 20, and the second binding site K2 is set at a position offset below the side sill 20, but the first binding site is reversed. Even when the position K1 is set at a position shifted downward from the side sill 20 and the second binding site K2 is set at a position shifted upward from the side sill 20, similar actions and effects can be achieved.
[0049]
10 and 11 show a second embodiment of the present invention, in which the same components as those in the first embodiment are denoted by the same reference numerals and redundant description is omitted.
[0050]
FIG. 10 is a rear perspective view showing the main part of the lower member constituting the front side member, and FIG. 11 is an enlarged sectional view taken along the line CC in FIG.
[0051]
In the vehicle body front part structure of the second embodiment, a member rear part 10B of a front side member 10 is joined to a lower member 10C 'and an upper member 10D', each formed of a light alloy casting such as aluminum as shown in FIG. Thus, a closed cross section is formed.
[0052]
As shown in FIG. 10, the lower member 10C ′ is formed in a U-shaped cross section in the same manner as the press-formed lower member 10C of the first embodiment, and the outrigger 12 forming portion 12A, the extension member 13 forming portion 13A, and the member A forming portion 17A of the connecting portion 17 is integrally formed.
[0053]
In the forming portion 17A of the member connecting portion 17, as shown in FIG. 11, a boss portion 17A1 through which a mounting bolt B1 for connecting the rear lateral member 15d of the suspension member 15 is inserted, and the boss portion 17A1 project radially. A plurality of ribs 17A2 coupled to the inner wall of the portion 17A are integrally formed, and one rib 17A2 'of the plurality of ribs 17A2 is coupled to the vertical wall 13A1' of the forming portion 13A of the extension member 13 with continuity.
[0054]
Of course, even in this embodiment, the upper member 10D ′ is formed along the upper shape of the lower member 10C ′ in which the respective forming portions 12A, 13A, and 17A are integrally formed. As shown in FIG. After the upper open portion of 'is closed by the upper member 10D', both of them are joined together by welding.
[0055]
Therefore, in the vehicle body front portion structure of the second embodiment, the rib 17A2 'protruding from the boss portion 17A1 provided in the forming portion 17A of the member connecting portion 17 is used as the vertical wall of the forming portion 13A of the extension member 13. Since it is coupled to 13A1 ′ with continuity, the load fs (see FIG. 9) at the time of a side collision can be reliably transmitted to the member connecting portion 17 by the in-plane force of the vertical wall 13A1 ′ as in the first embodiment. it can.
[0056]
In the second embodiment, the member rear portion 10B of the front side member 10 is formed of a light alloy casting, so that the number of parts can be reduced, the number of assembly steps can be reduced, and the productivity of the vehicle body can be improved.
[0057]
By the way, in the vehicle body front structure of the present invention, the first and second embodiments have been described as examples. However, the present invention is not limited thereto, and other various embodiments are within the scope of the present invention. Can be taken.
[Brief description of the drawings]
FIG. 1 is a plan view showing a skeleton structure of a vehicle body in a first embodiment of the invention.
FIG. 2 is a side view showing a skeleton structure of a vehicle body in the first embodiment of the invention.
FIG. 3 is an exploded perspective view showing the main part of the skeleton structure of the front part of the vehicle body in the first embodiment of the present invention.
4 is an enlarged sectional view taken along line AA in FIG. 1. FIG.
FIG. 5 is an enlarged cross-sectional view along the line BB in FIG. 1;
FIG. 6 is a perspective view showing a main part of a lower member constituting the front side member in the first embodiment of the present invention.
FIG. 7 is a main part plan view showing a skeleton structure on the left side of the front part of the vehicle body in the first embodiment of the present invention.
FIG. 8 is a left side perspective view showing the moment acting on the side sill in the first embodiment of the present invention.
FIG. 9 is a plan view of a main part of the vehicle body skeleton showing a load flow at the time of a side collision in the first embodiment of the present invention.
FIG. 10 is a perspective view showing a main part of a lower member constituting a front side member according to a second embodiment of the present invention.
11 is an enlarged sectional view taken along the line CC in FIG.
[Explanation of symbols]
10 Front side members 10C, 10C 'Lower member 12 Outrigger (first connecting member)
12A Outrigger formation part 13 Extension member (second connecting member)
13A Extension member forming portion 13A1 Extension member vertical wall 14 Dash cross member (third connecting member)
15 Suspension member 15d Rear lateral member 17 Member connecting portion 17A Member connecting portion forming portion 17A1 Boss portion 17A2 'Rib 17C Support plate 17C1 Support plate vertical wall 20 Side sill C Cabin Pf Floor panel K1 First connecting portion K2 Second connecting portion D1 Branch portion D2 of the first connecting member D2 Branch portion B1 of the second connecting member Mounting bolt (fastening member)

Claims (5)

A front side member that extends in the vehicle longitudinal direction on both sides in the vehicle width direction at the front of the vehicle body and has a vehicle rear end inclined downward, and a side sill that extends in the vehicle longitudinal direction on both sides in the vehicle width direction of the floor panel. The vehicle body rear end portion of the front side member is coupled to the vehicle body front end portion of the side sill via the first coupling member, and the vehicle body is located more than the coupling site of the first coupling member of the side sill via the second coupling member. In the vehicle body front structure connected to the rear,
The first connecting portion between the first connecting member and the side sill is set at a position offset to either above or below the side sill, and the second connecting portion between the second connecting member and the side sill is set to the first connecting portion. A vehicle body front structure characterized in that it is set at a position that is offset in the opposite direction to the part. The vehicle body front part structure according to claim 1, wherein an upper side of the front side member at a rear end portion of the vehicle body in the vicinity of the branch portion of the first connection member is supported by the front pillar via a third connection member. 3. The vehicle body according to claim 1, wherein a member connecting portion for connecting both end portions of a rear lateral member of the suspension member disposed below the front side member is provided at a rear end portion of the vehicle body of the front side member. Front structure. At least a part of the front side member has a closed cross-sectional structure including a lower member integrally formed in a U-shaped cross section including a first connecting member, a second connecting member, and a member connecting portion by press molding of a plate material, A support plate for supporting the fastening member of the rear lateral member is provided in the upper open portion in the connecting portion forming portion, and at least the vehicle body rear side of the vertical wall provided on the front side member side of the support plate is connected to the second connecting member. The vehicle body front part structure according to claim 3, wherein the front body structure is connected to the vertical wall of the forming portion of the vehicle body continuously. At least a part of the front side member has a closed cross-sectional structure including a lower member integrally formed in a U-shaped cross section including a first connecting member, a second connecting member, and a member connecting portion by light alloy casting, and the member connecting A boss portion through which the fastening member of the rear lateral member is inserted and a plurality of ribs protruding radially from the boss portion and coupled to the inner wall of the formation portion are integrally formed in the formation portion of the portion, and at least one of the plurality of ribs The vehicle body front part structure according to claim 3, wherein the vehicle body is continuously connected to the vertical wall of the portion where the second connecting member is formed.

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