JP2006232147A - Vehicle body front structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle body front structure capable of suppressing cabin deformation when the vehicle makes head-on collision while the weight of the vehicle body is suppressed. <P>SOLUTION: The vehicle body front structure 10 is equipped with a front side member 12 whose longitudinal direction stretches fore and aft of the vehicle and with the front end 12A coupled with a bumper reinforcement 14, a floor under reinforcement 18 with its front end 18A coupled with the tail 12B of the front side member 12 and supporting the load input to the front side member 12 from the bumper reinforcement 14, a front pillar reinforcement 28 with its rear top coupled with the roof structure of the body and reinforcing the front pillar upper 27, and a coupling member 34 to couple the tail of the front side member 12 with the front bottom of the front pillar reinforcement 28 and transmitting part of the load input to the front side member 12 from the bumper reinforcement 14 to the front pillar 24. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicle body front part structure for absorbing an impact at the time of a frontal collision of a vehicle.

A first reinforcing member for transmitting a load input to the front bumper to the cowl box via the upper edge of the hoodage panel in order to effectively absorb the impact energy at the time of the frontal collision of the vehicle to the front side member, and the cowl box There is known a technique of providing a first reinforcing member that transmits the load input to the front side member as a forward repulsive force (see, for example, Patent Document 1). In the technique described in this document, in order to transmit the repulsive force to the front side member, in addition to the first and second reinforcing members, a load transmission part in the vehicle body such as a beam of a hoodage panel, a brace of a cowl box, etc. A reinforcing member is provided in the load supporting portion.
JP-A-4-262975 Japanese Utility Model Publication No. 3-2880 JP-A-11-291952

  However, the conventional technology as described above is configured to absorb the impact energy (relax the impact load) by applying a force to sandwich the front side member from the front and rear to sufficiently deform the front side member. The load input to the vehicle body (supported by the vehicle body) via the upper edge of the panel was not relaxed. For this reason, it is indispensable to reinforce the load transmitting portion and load supporting portion of the vehicle body described above, and it has been difficult to reduce the weight of the vehicle body.

  An object of the present invention is to obtain a vehicle body front portion structure that can suppress deformation of a vehicle compartment at the time of a frontal collision of a vehicle while suppressing an increase in vehicle body weight in consideration of the above fact.

  In order to achieve the above object, a vehicle body front structure according to the first aspect of the present invention is a front side that is elongated in the vehicle longitudinal direction, the front end is connected to the front bumper, and the rear end is connected to the floor frame member. A member, and a load distribution member that transmits a part of a backward load input from the front bumper to the front side member to a front pillar of a vehicle body.

  In the vehicle body front part structure according to the first aspect, the collision load input to the front bumper is transmitted to the floor frame member from the front side member that is elongated in the longitudinal direction of the vehicle body. At this time, the impact energy absorbed by the deformation of the front side member and the impact load transmitted to the floor skeleton member is alleviated.

  Here, since the load distribution member for transmitting a part of the load input from the front bumper to the front side member to the front pillar of the vehicle body is provided, a part of the impact load due to the front collision of the vehicle is supported by the front pillar. That is, the collision load is shared and supported (distributed) by the floor skeleton member and the front pillar, and the load transmitted to the floor skeleton member is alleviated. Thereby, the deformation | transformation of the compartment accompanying a frontal collision is suppressed without resorting to reinforcement. Further, since the deformation of the passenger compartment is suppressed (the rigidity of the passenger compartment is improved), reliable deformation of the front side member due to the collision load, that is, impact energy absorption is ensured.

  Thus, in the vehicle body front part structure according to the first aspect, it is possible to suppress the deformation of the vehicle compartment at the time of the frontal collision of the vehicle while suppressing an increase in the vehicle body weight.

  In order to achieve the above object, a vehicle body front structure according to a second aspect of the present invention has a front side member that is elongated in the vehicle front-rear direction and has a front end connected to a front bumper, and a front end side that is located behind the front side member. A floor skeleton member coupled to an end side and supporting a load input to the front side member from the front bumper; a front pillar elongated in a vehicle vertical direction; and a rear end side of the front side member or the floor A connecting member that connects a front end side of the skeleton member and a portion of the front pillar that is located above the side member, and transmits a part of the load input from the front bumper to the front side member to the front pillar. And.

  In the vehicle body front structure according to the second aspect, the collision load input to the front bumper is transmitted to the floor frame member from the front side member which is elongated in the longitudinal direction of the vehicle body. At this time, when the front side member is deformed, the impact energy is absorbed, and the impact load transmitted to the floor skeleton member is alleviated.

  Here, since the connecting member that connects the rear end of the front side member or the front end of the floor skeleton member and the upper portion of the front pillar than the front side member is provided, a part of the impact load accompanying the front collision of the vehicle is connected to the connecting member. Is transmitted to the front pillar. That is, the collision load is shared and supported (distributed) by the floor skeleton member and the front pillar, and the load transmitted to the floor skeleton member is alleviated. Thereby, a deformation | transformation of a compartment is suppressed, without resorting to reinforcement. Further, since the deformation of the passenger compartment is suppressed (the rigidity of the passenger compartment is improved), the front side member is reliably deformed by the collision load, that is, energy absorption is ensured.

  Thus, in the vehicle body front portion structure according to claim 2, it is possible to suppress the vehicle compartment deformation at the time of the frontal collision of the vehicle while suppressing an increase in the vehicle body weight.

  The vehicle body front part structure according to a third aspect of the invention is the vehicle body front part structure according to the second aspect, wherein the upper end of the connecting member is a load applied to the front side member from the front bumper at the front pillar. It is connected to a position where it is transmitted to a connecting portion with the cowl portion of the vehicle body.

  In the vehicle body front structure according to claim 3, the collision load is connected to the cowl portion of the front pillar from the front side member via the connecting member (for example, a portion located immediately behind the cowl side portion or the apron portion). ) Or its vicinity. For this reason, the load dispersed by the connecting member is reliably transmitted to the highly rigid portion of the front pillar and supported by the front pillar, and deformation of the passenger compartment is effectively suppressed.

  As described above, the vehicle body front part structure according to the present invention has an excellent effect that the vehicle compartment deformation at the time of a frontal collision of the vehicle can be suppressed while suppressing an increase in the vehicle body weight.

  A vehicle body front structure 10 according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. It should be noted that the arrow FR, arrow RE, arrow UP, arrow LO, arrow IN, and arrow OUT that are appropriately shown in each figure are the forward direction (traveling direction) and the backward direction of the vehicle body S to which the vehicle body front structure 10 is applied, respectively. The upper direction, the lower direction, the inner side in the vehicle width direction, and the outer side in the vehicle width direction are shown. In the following, when the front and back, front and rear, and the inner and outer sides in the vehicle width direction are shown, they correspond to the arrow directions.

  FIG. 1 is a perspective view of a front right side portion (one side with respect to the center in the vehicle width direction) of a vehicle body S to which the vehicle body front structure 10 is applied. Since the vehicle body front structure 10 is basically formed symmetrically in the left-right direction (in the vehicle width direction), only the right side portion of the vehicle body will be described below. As shown in FIG. 1, front side members 12 that are elongated in the longitudinal direction of the vehicle body are disposed at both ends in the vehicle width direction at the front portion of the vehicle body S.

  A bumper reinforcement 14 constituting a front bumper is installed on the front end 12A of the left and right front side members 12, and when the vehicle body S has a front collision (front collision), an impact load is generated from the bumper reinforcement 14. Input is made to the left and right front side members 12. In this embodiment, a crash box 16 is disposed between the front end 12A of the front side member 12 and the bumper reinforcement 14 and is more easily deformed than the front side member 12 due to a front and rear impact load caused by a front collision. Yes. Although not shown, the crash box 16 whose front end is fixed to the bumper reinforcement 14 by welding has a flange 16A provided at the rear end thereof and a flange 12C provided at the front end of the front side member 12 with bolts and nuts. And is attached to the front side member 12.

  The front side member 12 is linearly disposed along the front-rear direction of the vehicle body including the front end portion 12A, and has a closed cross-sectional structure having a substantially rectangular cross-sectional shape when viewed from the front-rear direction of the vehicle body. On the other hand, the rear end portion 12B of the front side member 12 is a kick portion inclined from the upper front side of the vehicle body toward the lower rear side of the vehicle body. A front end 18A of a floor under reinforcement 18 as a floor frame member is connected to the rear end 12B of the front side member 12.

  Specifically, the floor under reinforcement 18 has a hat shape in which a cross-sectional shape viewed from the front-rear direction of the vehicle body opens upward, and flanges formed on both sides of the opening end are the floor panel 20 (FIG. 2 (A ))) To form a closed cross-sectional structure. The front end portion 18A of the floor under reinforcement 18 is a kick portion having a hat-shaped cross section similar to the portion for reinforcing the floor panel 20 and inclined corresponding to the rear end portion 12B of the front side member 12. Each flange is joined to the lower surface of the rear lower portion of the dash panel 22 to form a closed cross-sectional structure. A front end portion 18A of the floor under reinforcement 18 is connected to a rear end portion 12B joined to a front surface of a dash panel 22 that partitions the vehicle compartment C and the engine room in the front side member 12. The dash panel 22 is disposed between the left and right front pillars 24.

  As shown in FIG. 1, FIG. 2 (A), and FIG. 2 (B), the portion of the dash panel 22 where the rear end portion 12B of the front side member 12 is joined is elongated in the left-right direction and left and right fronts. A dash cross member 30 that bridges the pillar 24 is disposed. The dash cross member 30 reinforces the dash panel 22 by forming a closed cross-sectional structure when viewed from the side of the vehicle body S with the dash panel 22. As described above, in the vehicle body front structure 10, the load input from the bumper reinforcement 14 to the front side member 12 is supported by the floor structure F including the floor under reinforcement 18 and the dash cross member 30. ing. In this embodiment, the dash cross member 30 together with the floor under reinforcement 18 corresponds to the floor skeleton member in the present invention.

  The front pillar 24 is inclined so that the upper end is located rearward of the front pillar lower 26 that is elongated along the vertical direction of the vehicle body and the lower end continuous with the upper end of the front pillar lower 26. The front pillar upper 27 is formed. The lower end of the front pillar lower 26 is integrated with a rocker 32 that is elongated in the longitudinal direction of the vehicle body. On the other hand, the upper rear end of the front pillar upper 27 is connected to the roof structure portion R. The roof structure portion R is connected to a skeleton portion at the lower part of the vehicle body via left and right front pillars 24, left and right rear pillars (and left and right center pillars) not shown. Further, a front pillar reinforcement (side member) 28 is disposed in the front pillar upper 27 over the entire length thereof.

  Further, in front of the boundary portion between the front pillar lower 26 and the front pillar upper 27, that is, the front pillar reinforcement 28, a cowl side panel 34 as a cowl portion for connecting an apron reinforcement and a cowl panel (both not shown). Are joined. The cowl side panel 34 is connected to the top of the suspension tower 38 via a suspension tower top plate 36. In this embodiment, the suspension tower top plate 36 is formed in a substantially dish shape that opens downward, and the top of the suspension tower 38 is inserted. The suspension tower top plate 36 is joined to the dash panel 22 or the cowl panel at the rear end 36A.

  The vehicle body front structure 10 includes a connecting member 40 as a load distribution member. The connecting member 40 connects a portion in the vicinity of the rear end portion 12B of the front side member 12 and a portion in the vicinity of the lower end portion of the front pillar reinforcement 28, and a part of the backward load acting on the front side member 12 is transferred to the front pillar 24. To communicate. That is, in the vehicle body front structure 10, the rearward load acting on the front side member 12 causes the dash structure D including the dash panel 22, the dash cross member 30, and the front end portion (kick portion) 18 </ b> A of the floor under reinforcement 18. To the floor structure F and the front pillar 24. Hereinafter, the connecting member 40 will be specifically described.

  In this embodiment, the connecting member 40 is disposed along the front surface (in the vertical direction) of the dash panel 22 as shown in FIG. The suspension member 40 has a lower end 40A joined to an outward surface in the vehicle width direction in the vicinity of the front end 12A of the front side member 12, and an upper end 40B fixedly connected to the cowl side panel 34. The top plate 36 is joined to the peripheral wall on the rear side. For this reason, as shown in FIG. 2 (C), the connecting member 40 is formed so as to incline linearly so that the intermediate portion 40C in the longitudinal direction is positioned on the outer side in the vehicle width direction with respect to the upper end 40B. ing. The intermediate portion 40C has a hat shape in which a cross-sectional shape orthogonal to the longitudinal direction opens rearward, and a flange is joined to the front surface of the dash panel 22 to form a closed cross-sectional structure.

  As described above, in the vehicle body front structure 10, the region where the front side member 12, the dash cross member 30, and the floor under reinforcement 18 in the dash panel 22 are gathered together to be highly rigid, and the cowl side panel 34 (the cowl portion and The apron portion), the suspension tower 38, and the front pillar 24 are connected to each other by a connecting member 40 in a region where high rigidity is obtained. As a result, a skeleton surrounding the vehicle compartment C is formed from the front pillar 24 to the floor under reinforcement 18 via the connecting member 40 and the front side member 12. In other words, the connecting member 40 constitutes a vehicle body skeleton that extends across the floor structure portion F, the dash structure portion D, the front pillar 24, and the roof structure portion R.

  Next, the operation of the first embodiment will be described.

  When a vehicle to which the vehicle body front structure 10 having the above configuration is applied reaches a frontal collision, a rearward impact load is input from the bumper reinforcement 14 to the front side member 12. At this time, the crash box 16 is first axially deformed (axial collapse) in the axial direction, and then the front side member 12 is bent at the middle portion in the longitudinal direction to absorb impact energy. Thereby, the impact load transmitted to the dash structure portion D and the floor structure portion F constituting the vehicle compartment C in the vehicle body S is alleviated, and deformation of the vehicle compartment C is suppressed.

  Here, since the connecting member 40 that connects the front side member 12 (the highly rigid portion of the dash structure portion D) and the suspension tower top plate 36 is provided, a part of the backward load acting on the front side member 12 is the connecting member. 40, and transmitted to the front pillar 24 via the suspension tower top plate 36 (the cowl side panel 34). In other words, the backward load acting on the front side member 12 is distributed and transmitted to the floor structure portion F and the front pillar 24 of the vehicle body S as indicated by arrows in FIG. It is shared and supported by the pillar 24. As a result, the front side member 12 whose rear end is securely supported receives the impact load, absorbs the impact energy effectively while being reliably deformed, and is transmitted to the floor structure portion F and the front pillar 24. And the deformation of the passenger compartment C is effectively suppressed.

  Therefore, the load acting on the floor structure portion F at the time of the front collision is further relaxed together with being supported by the front pillar 24, and the reinforcement of the floor structure portion F with respect to the front collision load can be simplified. For example, in a configuration that does not include the connecting member 40, the front end member 18A (kick portion) of the floor under-reinforcement 18 is used to reliably deform the front side member 12 to absorb impact energy and suppress deformation of the passenger compartment C. ), However, an excessive countermeasure mass is generated in the front lower portion of the vehicle body due to an unbalanced reinforcement increase mainly for supporting the collision load in the floor structure portion F. In the vehicle body front structure 10 according to the present embodiment, a part of the front impact load is shared and supported by the front pillar 24, so that the load support is well balanced and the reinforcement (the ratio depending on) of each part is reduced. It was. That is, by supporting the load with the floor structure portion F and the front pillar 24 located on the opposite side in the vertical direction with respect to the front side member 12, the apparent sectional modulus is increased (the bending of the kick portion 18A is remarkably relieved). A configuration that supports the front impact load without relying on reinforcement was realized. In the vehicle body front structure 10, as in the disclosed prior art (Patent Document 1), the second reinforcing member generates a repulsive force (the load is reliably transmitted to the second reinforcing member) and the second reinforcing member. Needless to say, one reinforcing member is not required.

  In this embodiment, by providing the connecting member 40 that uses the strength of the front pillar 24 at the time of the front collision, the floor structure portion F and the front pillar 24 do not have any special reinforcement for the front collision, that is, other functions. The structure which ensures the required front-end collision performance by the reinforcement | strengthening to respond | correspond to the said request | requirement is implement | achieved. In the vehicle body front structure 10, the connecting member 40 is connected to the suspension tower top plate 36 located in the vicinity of the connecting portion with the cowl side panel 34, which is a highly rigid portion in the front pillar 24, so that the front pillar 24. Since the (front pillar upper 27) supports the load input from the front and lower ends along the longitudinal direction (compression direction), the deformation of the passenger compartment C is further effectively suppressed.

  Thus, in the vehicle body front structure 10 according to the present embodiment, it is possible to suppress the deformation of the vehicle compartment at the time of a frontal collision of the vehicle while suppressing an increase in the weight of the vehicle body S. In particular, in an automobile with a small front overhang, such as a so-called compact car, the shock absorption region (stroke) due to the deformation of the front side member 12 is small. Therefore, the front side member 12 is reliably deformed in a limited region, and impact energy is generated. The vehicle body front part structure 10 according to the present embodiment is effectively applied.

  Next, a second embodiment of the present invention will be described. Note that parts and portions that are basically the same as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and description and illustration thereof are omitted.

  FIG. 3 is a perspective view of a front right side portion (one side with respect to the center portion in the vehicle width direction) of the vehicle body S to which the vehicle body front portion structure 50 according to the second embodiment is applied. As shown in FIG. 4 and FIG. 4, in the vehicle body front structure 50, in addition to the connection member 40, a connection member 52 that connects the longitudinal intermediate portion of the front side member 12 and the cowl side panel 34 is provided. Yes. The connecting member 52 suppresses bending deformation (bending) of the front side member 12.

  Specifically, the front lower end 52A of the connecting member 52 is joined to the side wall on the vehicle width direction outer side of the rear portion of the front side member 12 of the flange 12C (front side of the front end of the cowl side panel 34). The upper end 52B is joined to the front end of the cowl side panel 34. Therefore, the connecting member 52 is tilted rearward as shown in FIG. 4A in the side view, and the outer end in the vehicle width direction (the rear upper end 52B) is the inner end in the plan view as shown in FIG. 4B. The vehicle is inclined so as to be positioned rearward of the front lower end 52A, and the outer end in the vehicle width direction, that is, the joint end to the cowl side panel 34 is curved backward. Further, in the rear view, the connecting member 52 is linearly inclined so that the outer end 52B in the vehicle width direction is located above the inner end 52A as shown in FIG. 4C.

  Other configurations of the vehicle body front structure 50 are the same as the corresponding configurations of the vehicle body front structure 10. Therefore, the vehicle body front part structure 50 has basically the same effects as the vehicle body front part structure 10 according to the first embodiment.

  The vehicle body front structure 50 described above is different from the vehicle body front structure 10 according to the first embodiment in the action at the time of a frontal collision at a relatively low speed (hereinafter referred to as a light collision). That is, in the vehicle body front structure 50, the bending deformation of the front side member 12 is suppressed by the connecting member at the time of a light collision, and impact energy is absorbed mainly by the axial compression deformation of the crash box 16. For this reason, damage due to a light collision is prevented from occurring in the rear part from the front side member 12 which is a skeletal member located behind the crash box S16 in the vehicle body S, and the bumper reinforcement 14 and the crash box 16 are repaired. It is enough to exchange Since the crash box 16 (bumper reinforcement 14) and the front side member 12 are detachably fastened and connected with bolts and nuts, there is no need for welding repair.

  Thus, in the vehicle body front part structure 50 according to the second embodiment, it is possible to reduce the number of parts requiring repair due to a light collision, and it is possible to simplify the repair work. The effect is that the impact load at the time of a light collision is distributed and supported by the floor structure F and the front pillar 24 via the front side member 12, so that the deformation of the vehicle body S (vehicle compartment C) is suppressed, and the crash box 16 In this case, the impact load is concentrated and acts (the impact load is mainly used for deformation of the crash box), that is, by providing the connecting member 40, it is effectively achieved.

  In each of the above-described embodiments, the example in which the connecting member 40 connects the front side member 12 and the suspension tower top plate 36 has been described. However, the present invention is not limited to this, and the connecting member 40 may be the front side member. As long as a part of the backward load acting on 12 can be transmitted to the front pillar 24, any portion may be connected. Therefore, for example, the connecting member 40 may be disposed on the cabin C side (rear side) of the dash panel 22 so that the connecting member 40 connects the floor under reinforcement 18 and the cowl side panel 34 (cowl panel). May be.

1 is a perspective view of a vehicle body right front portion showing a vehicle body front portion structure according to a first embodiment of the present invention. It is a figure which shows the vehicle body front part structure which concerns on the 1st Embodiment of this invention, Comprising: (A) is a side view, (B) is a top view, (C) is a rear view. It is a perspective view of the vehicle body right front part which shows the vehicle body front part structure which concerns on the 2nd Embodiment of this invention. It is a figure which shows the vehicle body front part structure which concerns on the 2nd Embodiment of this invention, Comprising: (A) is a side view, (B) is a top view, (C) is a rear view.

Explanation of symbols

10 Car body front structure 12 Front side member 14 Bumper reinforcement (front bumper)
18 Floor under reinforcement (Floor frame member)
24 Front Pillar 28 Front Pillar Reinforcement (Front Pillar Reinforcement Member)
30 dash cross member (floor frame member)
40 Connecting member (Load distribution member)
50 Car body front structure S Car body

Claims (3)

A front side member that is elongated in the vehicle longitudinal direction, the front end is connected to the front bumper and the rear end is connected to the floor skeleton member;
A load distribution member that transmits a part of a rearward load input from the front bumper to the front side member to a front pillar of a vehicle body;
Body front structure with A front side member which is elongated in the vehicle longitudinal direction and whose front end is connected to the front bumper;
A floor skeleton member that is connected to a rear end side of the front side member at a front end side and supports a load input to the front side member from the front bumper;
A front pillar that is elongated in the vertical direction of the vehicle,
A load input to the front side member from the front bumper by connecting a rear end side of the front side member or a front end side of the floor skeleton member and a portion of the front pillar positioned above the side member. A connecting member that transmits a part of the front pillar to the front pillar;
Body front structure with   The front end of the vehicle body according to claim 2, wherein an upper end of the connection member is connected to a position where a load input from the front bumper to the front side member is transmitted to a connection portion of the front pillar with a cowl portion of the vehicle body. Part structure.

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