JP4930016B2 - Auto body front structure - Google Patents

Description

  The present invention relates to a vehicle body front structure, particularly a dash corner structure in which a dash panel and a dash side panel are connected.

Conventionally, in order to increase the flexural rigidity of the front pillar, the front pillar and a box-shaped front deck extending in the vehicle width direction in front of the front pillar are connected obliquely with gussets for stiffening. What was made to do is known (refer patent document 1).
Japanese Patent No. 3673894 (page 3, FIG. 1)

  In the event of a frontal collision of the vehicle, if a collision load acts on the front side member that extends in the front-rear direction on the lower side of the hood ridge panel that forms the side wall of the engine room, the rear end of this front side member is joined. The dash panel acts as a deformation load in the backward direction. However, the conventional stiffening structure of the front pillar by the gusset hardly contributes to suppressing the backward deformation of the dash panel toward the vehicle interior side.

  Accordingly, the present invention provides a vehicle body front structure that can efficiently disperse and transmit a collision load input from a front side member to a dash panel during a frontal collision of a vehicle to the front pillar side.

In the vehicle body front structure of the present invention, the vehicle body front structure is disposed at a corner formed by a dash panel and a dash side panel, and one end side is coupled to a position facing the rear end of the front side member with the dash panel interposed therebetween. , a reinforcing member the other end is coupled to the dash side panels provided, the reinforcing member includes a top wall, a lower wall, on these, you open toward the front of the vehicle and a rear wall which continuously provided a lower wall Yes formed in a U-shaped section, the at least one of the upper wall and the lower wall of the reinforcing member to form a bead portion extending in the vehicle longitudinal direction, the bead portion in a plan view perpendicular to the rear wall The main feature is that it is formed at an angle of 45 ° toward the outside in the vehicle width direction with respect to the vehicle longitudinal direction .

  According to the vehicle body front structure of the present invention, a collision input acting in the axial direction on the front side member at the time of a frontal collision of the vehicle is input to the vehicle interior side at a portion where the rear end of the front side member of the dash panel is coupled. However, one end side of the reinforcing member is connected to the position corresponding to the rear end of the front side member of the dash panel, and the other end side is connected to the dash side panel. Since this reinforcing member exists as a beam member connecting the two at the corner formed by the side panel, the input acting from the front side member is distributed and transmitted to the dash side panel via the reinforcing member.

  Since this dash side panel constitutes a pillar inner of the lower part of the front pillar, the distributed and transmitted input is further transferred from the front pillar to other body frame members such as a side sill and a roof side rail. Distributed transmission.

  At this time, since the reinforcing member forms a bead portion extending in the front-rear direction, the drag force from the front is high, and the bending deformation is suppressed to a small extent, and the input can be more efficiently distributed to the dash side panel. Can do.

As a result, the amount of backward deformation in the vehicle interior direction around the front side member coupling portion of the dash panel can be suppressed as small as possible, and a living space around the passenger foot portion can be secured.
In addition, the reinforcing member is formed in a substantially U-shaped cross section that opens to the front of the vehicle on the upper, lower and rear walls, so that the collision load input from the rear end of the front side member is distributed vertically on the upper and lower walls. In addition to the transmission to the dash side panel, it is possible to efficiently perform distributed transmission to the dash side panel via the lower ridge line on the high rigidity of the boundary between the upper and lower walls and the rear wall.
In addition, since the reinforcing member is formed in a triangular shape in plan view so that the rear wall connects the dash panel and the dash side panel diagonally, the beam rigidity of the upper and lower ridge lines of the rear wall is fully functioned. Thus, the collision load input from the rear end of the front side member can be more efficiently transmitted to the dash side panel side.
Furthermore, the upper and lower ridges of the rear wall of the reinforcing member are formed so as to connect the dash panel and the dash side panel obliquely in plan view, and at least one of the plurality of bead portions of the upper wall and the lower wall Since it extends in the front-rear direction perpendicular to the rear wall in a plan view, the collision load acts substantially parallel to the axis of these bead parts, so the bending rigidity of the upper and lower walls against the collision load is Therefore, the overall resistance of the reinforcing member is high, and input transmission to the dash side panel can be efficiently performed even in the middle of the collision.
Further, the bead portion extending in the front-rear direction of at least one of the upper and lower walls is formed at an angle of 45 ° toward the outer side in the vehicle width direction with respect to the vehicle front-rear direction. The drag of the member can be increased, and the retreat amount of the member in the vicinity of the rear end of the front side member can be suppressed small.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  1 to 8 show an embodiment of a front body structure of an automobile according to the present invention. FIG. 1 is a perspective view showing a state in which a reinforcing member is arranged as seen from the vehicle interior side. FIG. FIG. 3 is an enlarged perspective view of the reinforcing member shown in FIG. 1, FIG. 4 is a perspective view seen from an oblique side of the reinforcing member, and FIG. 5 is a perspective view seen from the front of the reinforcing member. It is.

  6 is a plan view for explaining the deformation behavior of the front side member, the reinforcing member, and the like at the time of the front collision of the vehicle, in order of (A) and (B). FIG. 7 is a graph showing the drag of the reinforcing member. Is a graph showing the retraction amount of the dash panel and the front pillar.

  As shown in FIGS. 1 and 2, the vehicle body front portion structure of the present embodiment includes front side members 1 as front and rear skeleton members on both sides in the vehicle width direction of the front compartments F and C.

  A cross member 2 and a front bumper 3 are coupled between the front end portions of the left and right front side members 1 (see FIG. 6), and the rear end of each front side member 1 separates the front compartment F · C and the vehicle compartment R. The dash panel (dash lower panel) 4 is joined and welded.

  Although not shown, the rear end portion of the front side member 1 extends from the dash panel 4 to the lower surface side of the floor panel 5 as a front side member extension and extends rearward of the floor.

  Both ends of the dash panel 4 in the vehicle width direction are joined to the dash side panel 6 by welding.

  A front pillar lower outer 7 is joined to the outer surface of the dash side panel 6 to form a front pillar 8 having a closed cross section.

  Accordingly, the dash side panel 6 constitutes a pillar inner of the front pillar 8, and the lower end of the front pillar 8 is joined to the side edge of the floor panel 5 and is one of floor skeleton members extending in the longitudinal direction of the vehicle body. The side sill 10 is connected to the front end portion.

  A front wheel house inner portion 9 is formed on both sides of the dash panel 4 in the vehicle width direction so as to be adjacent to the dash side panel 6 and bulge toward the vehicle interior side.

  The front wheel house inner portion 9 is enlarged as the amount of bulging toward the vehicle interior side goes downward.

  One end of the dash panel 4 is opposed to the rear end of the front side member 1 across the dash panel 4 at the corners formed by the dash panel 4 and the dash side panel 6 at both sides of the dash panel 4 in the vehicle width direction. The reinforcing member 11 is provided that is coupled to the position where the other end is coupled to the dash side panel 6.

  As shown in FIGS. 3 to 5, the reinforcing member 11 includes an upper wall 12, a lower wall 13, and a rear wall 14 connecting the upper and lower walls 12, 13, and opens to the front of the vehicle. It is formed in a substantially U-shaped cross section.

  Further, in at least one of the upper wall 12 and the lower wall 13, for example, in this embodiment, a plurality of bead portions 15 extending substantially in the front-rear direction are respectively provided on both the upper wall 12 and the lower wall 13. It is formed to bulge toward the outside of the U-shaped cross section.

The reinforcing member 11, rear wall 14 Yes formed in plan view substantially triangular shape so as to connect the dash panel 4 and the dash side panel 6 to slant, plane the bead portion 15 relative to the rear wall 14 are then viewed substantially right angle formation.

  In addition, the reinforcing member 11 is disposed so that the front edges of the upper wall 12 and the lower wall 13 cross the upper part of the front wheel house inner part 9 substantially horizontally, and is formed at the opening periphery of the substantially U-shaped cross section. Through the flange 11a, the general surface of the dash panel 4, the front wheel house inner portion 9, and the dash side panel 6 are respectively spot welded and joined.

  As described above, the front wheel house inner portion 9 is formed larger as the vehicle interior side bulge amount goes downward, and accordingly, the upper wall 12 and the lower wall 13 of the reinforcing member 11 Are formed such that the area of the upper wall 12 is larger than the area of the lower wall 13 in accordance with the corresponding position of the front wheel house inner portion 9 to which the respective leading edges are coupled.

  Therefore, the bead portion 15 is configured such that the set number of the upper wall 12 is larger than the set number of the lower wall 13 so that the panel rigidity of the upper and lower walls 12 and 13 is substantially equal.

  On the other hand, on the dash panel 4, a member member 16 extending in the vehicle width direction and joining one end side of the left and right reinforcing members 11, 11 is joined and disposed.

  This member member 16 is formed in a substantially U-shaped cross section, and in this embodiment, is joined to the side surface of the dash panel 4 on the front compartment F / C side by spot welding.

Therefore, the rear end of the front side member 1 is also joined to the upper and lower wall surfaces of the member member 16, and the end of the member member 16 in the vehicle width direction is as shown in FIG. , until the one end is joined portion of the reinforcing member 11 of the front wheel house inner portion 9, are bonded by spot welding to the front wheel house inner portion 9 extends as extending portion 16 a.

With the above configuration, according to the vehicle body front structure of the present embodiment, at the time of the frontal collision of the vehicle, at the initial stage of the collision (30 to 60 msec), as shown in FIG. The collision load F is input.

  The collision load F input to the front side member 1 in the axial direction is transmitted to the dash panel 4 as a uniformly distributed load Fa by a member member 16 extending in the vehicle width direction.

  In the portion where the rear end of the front side member 1 of the dash panel 4 is joined, it acts as a backward deformation load toward the vehicle interior side, but the dash panel 4 is reinforced at a position corresponding to the rear end of the front side member 1. One end side of the member 11 is coupled, the other end side is coupled to the dash side panel 6, and the reinforcing member 11 exists as a beam member connecting the two at the corner portion formed by the dash panel 4 and the dash side panel 6. Therefore, the input Fa acting from the front side member 1 is distributed and transmitted to the dash side panel 6 via the reinforcing member 11.

  Since this dash side panel 6 constitutes a pillar inner of the lower part of the front pillar 8, the distributed and transmitted input is transmitted from the front pillar 8 to the side sill 10 and the roof side rail (not shown). Further distributed transmission can be made to other vehicle body skeleton members.

  At this time, since the reinforcing member 11 is formed as a substantially U-shaped cross section that is opened to the front of the vehicle by the upper and lower walls 12 and 13 and the rear wall 14, a collision load input from the rear end of the front side member 1. The upper and lower walls 12 and 13 distribute Fa to the dash side panel 6 and transmit it to the dash side panel 6, and the upper and lower ridge line a portions of the high rigidity at the boundary between the upper and lower walls 12 and 13 and the rear wall 14. Distributed transmission to the dash side panel 6 can be efficiently performed via (see FIGS. 3 to 5).

  In addition, since a plurality of bead portions 15 extending in the front-rear direction are formed on the upper and lower walls 12 and 13, the resistance against the collision load Fa from the front of the upper wall 12 and the lower wall 13 is high. Thus, the vertical deformation of the lower walls 12 and 13 can be suppressed to be small, and the input can be distributed to the dash side panel 6 more efficiently.

Since the In the present embodiment, the reinforcing member 11, rear wall 14 is formed in plan view substantially triangular shape so as to connect the dash panel 4 and the dash side panel 6 to slant, after The beam rigidity of the upper and lower ridge lines a of the wall 14 can be sufficiently functioned to more efficiently transmit the collision load Fa input from the rear end of the front side member 1 to the dash side panel 6 side. Can be done.

  In the middle of the frontal collision (30 to 60 msec), as shown in FIG. 6 (B), the front-rear direction intermediate portion of the front side member 1 is bent and deformed outward in the vehicle width direction to reduce acceleration. .

  Then, a bending moment M is generated at the rear end portion of the front side member 1 toward the outer side in the vehicle width direction as shown by an arrow in FIG. The rotation input Fb enters from the front toward the vehicle center side.

Especially, extending portions 16a of the frame member 16 in the present embodiment, the reinforcement for extending up to the portion bonded to one end of the member 11, the rotary input Fb is reinforced through the frame member 16 member 11 The tendency to act on increases.

At this time, as described above, the upper and lower ridges a of the rear wall 14 of the reinforcing member 11 are formed so as to connect the dash panel 4 and the dash side panel 6 obliquely in plan view, and the upper wall 12 and the lower wall since a plurality of bead portions 15 of 13 extends in plan view substantially perpendicular to the longitudinal direction relative to the rear wall 14 this is as the rotation input Fb acts substantially parallel to the axis of the bead portion 15 Therefore, the bending rigidity of the upper and lower walls 12 and 13 with respect to the rotation input Fb is high. Therefore, the overall resistance of the reinforcing member 11 is high. Even in the middle of the collision, the dash side panel 6 side, that is, the front pillar Input transmission to the 8 side can be performed efficiently.

  As a result, the amount of backward deformation in the vehicle interior direction around the coupling portion at the rear end of the front side member 1 of the dash panel 4 is suppressed as small as possible, and a living space around the passenger's feet is secured. Can do.

  Here, according to the experiment of the present inventor, when there is no bead portion 15 on the upper and lower walls 12 and 13 of the reinforcing member 11, and when the bead portion 15 is in the vehicle longitudinal direction as shown in FIG. As described above, the reinforcing members 11 provided at angles of 0 °, 30 °, 45 °, 60 °, and 90 ° outward in the vehicle width direction with respect to the longitudinal axis of the front side member 1 are used. As shown in FIG. 7, when the front part of the vehicle body is formed and the drag of each reinforcing member 11 at the time of a vehicle frontal collision is measured, the one having the bead part 15 formed at an inclination angle of 45 ° has the highest drag. found.

  Further, at this time, the reverse amounts of the master back disposition portion, the brake pedal disposition portion, and the front pillar in the vicinity of the rear end of one front side member 1 are respectively a line, b line, and c line in FIG. As shown, it has been found that the retreat amount can be kept small in any case where the bead portion 15 is provided at the inclination angle of 45 °.

  Therefore, it is most preferable that the bead portions 15 extending in the front-rear direction of the upper and lower walls 12, 13 are formed at an angle of approximately 45 ° toward the outer side in the vehicle width direction with respect to the vehicle front-rear direction.

  In the present embodiment, the reinforcing member 11 is joined and disposed substantially horizontally across the front wheel house inner portion 9 in which the vehicle interior side bulge amount increases downward. Although the area of 12 is formed larger than the area of the lower wall 13, the set number of the bead portions 15 of the upper wall 12 is made larger than the set number of the bead portions 15 of the lower wall 13, and the upper and lower walls 12. , 13 have substantially the same panel rigidity, so that the upper wall 12 having a large area is not buckled and deformed by the collision loads Fa, Fb first, and the collision inputs Fa, Fb of the reinforcing member 11 do not occur. It is possible to keep the resistance against the high.

  Further, as described above, the dash panel 4 is provided with the member member 16 that extends in the vehicle width direction and joins the one end sides of the left and right reinforcing members 11, 11. Even when a collision load is input only from one front side member 1 at the time of a frontal collision, the non-collision-side reinforcing member 11 side is allowed to perform load dispersion and transmission almost simultaneously through the member member 16; An increase in the amount of backward deformation of the collision-side dash panel 4 can be avoided.

  The vehicle body front structure according to the present invention has been described by taking the above embodiment as an example. However, the present invention is not limited to this embodiment, and various other embodiments can be adopted without departing from the gist of the present invention. .

The perspective view seen from the vehicle interior side which shows the arrangement | positioning state of the reinforcement member in one Embodiment of this invention. The AA arrow directional plan view of FIG. The expansion perspective view of a reinforcement member. The perspective view seen from the diagonal side of a reinforcing member. The perspective view seen from the front of a reinforcement member. The top view explaining the deformation | transformation behavior of a front side member, a reinforcement member, etc. at the time of a vehicle front collision in order from (A) and (B). The graph which shows the drag of a reinforcement member. The graph which shows the amount of retreat of a dash panel and a front pillar.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front side member 4 Dash panel 6 Dash side panel 8 Front pillar 9 Front wheel house inner part 10 Side sill 11 Reinforcement member 12 Upper wall 13 Lower wall 14 Rear wall a Ridge line 15 Bead part 16 Member member

Claims (3)

A reinforcing member is disposed at a corner formed by a dash panel and a dash side panel, and one end side is coupled to a position facing the rear end of the front side member across the dash panel, and the other end side is coupled to the dash side panel. Provided,
The reinforcing member includes an upper wall, a lower wall, and a rear wall that continuously connects the upper and lower walls, and is formed in a U-shaped cross section that opens to the front of the vehicle, and the rear wall includes a dash panel and a dash side. It is formed in a triangular shape in plan view so as to connect the panel with the diagonal,
Wherein the at least one of the upper wall and the lower wall of the reinforcing member to form a bead portion extending in the vehicle longitudinal direction, the bead portion is formed in plan view perpendicular to the rear wall, and the longitudinal direction of the vehicle A vehicle body front structure, which is formed at an angle of 45 ° toward the outside in the vehicle width direction . In the corner formed by the dash panel and the dash side panel, a front wheel house inner part is formed in which the bulge amount toward the vehicle interior increases as it goes downward,
The reinforcing member has its upper, the middle portion front edge of the lower wall are arranged coupled across to the front wheel house inner portion horizontal,
The upper wall and the lower wall of the reinforcing member are formed such that the upper wall area is larger than the lower wall area in accordance with the corresponding position of the front wheel house inner part to which the respective front edges are joined.
2. The automobile according to claim 1, wherein the bead portion is provided on both the upper wall and the lower wall, and the number of bead portions provided on the upper wall is larger than the number of bead portions provided on the lower wall . Body front structure. The vehicle body front part structure according to claim 1 or 2 , wherein the dash panel includes a member member that extends in the vehicle width direction and connects the one end sides of the left and right reinforcing members.

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