WO2018029941A1

WO2018029941A1 - Vehicle body structure

Info

Publication number: WO2018029941A1
Application number: PCT/JP2017/019881
Authority: WO
Inventors: 真康吉田; 知仁鎌田; 貴之相馬; 知央渡部
Original assignee: 本田技研工業株式会社
Priority date: 2016-08-08
Filing date: 2017-05-29
Publication date: 2018-02-15
Also published as: CN109562794B; CN109562794A

Abstract

Provided is a vehicle body structure (1) which becomes deformed at a portion intended to be deformed and is capable of absorbing a collision load during a vehicle collision with minimal increase in vehicle weight and manufacturing cost. A reinforcing frame (60) which extends, in at least partially overlapping relation with a front side frame (50), along the vehicle longitudinal direction over a dash panel (10) and a floor panel (20) on an inner plate surface (FR2) facing a passenger compartment (R2) is spaced apart from a dash panel reinforcing member (80) by a predetermined distance. The site of the dash panel (10) and the front side frame (50) between the dash panel reinforcing member (80) and the reinforcing frame (60) is set as a weakened portion (17).

Description

Body structure

The present invention relates to a vehicle body structure continuous from a floor panel to a dash panel.

2. Description of the Related Art Conventionally, there has been conceived a vehicle body structure for relieving a load received by a lower leg of an occupant of a front seat when the vehicle is deformed by a frontal collision.
For example, in Patent Document 1, the kickup portion of the floor panel or the dash panel (the bending portion between the front end of the horizontal portion of the floor of the occupant's lower leg and the inclined portion of the floor that inclines forward and upward) Two dash cross members are arranged, and the front end of a reinforcement frame arranged upward along the floor frame is connected to these two dash cross members to strengthen the kickup portion and extend from the front of the vehicle at the time of a frontal collision There has been proposed a vehicle body structure in which a collision load transmitted to a vehicle compartment through a front side frame is dispersed to a reinforcing frame and a dash cross member.
And by making it the vehicle body structure which strengthens such a kickup part, it is suppressing that the lower-limb part of the passenger | crew in a vehicle interior deform | transforms at the time of a front collision.

Patent 5924331

By the way, in the vehicle body structure in which the kick-up portion is reinforced in Patent Document 1, the kick-up portion does not deform at the time of a frontal collision, but it bends at a site of low strength behind the reinforcement frame Rotate at. By such rotation, the amount of deformation toward the lower limbs of the vehicle body portion closer to the lower limbs is increased as compared with the case where the kickup portion is the fulcrum. The vehicle body portion close to the lower leg is a portion on the rear side of the reference numeral 85a in FIG. 1 and is a vehicle body portion facing the lower leg just outside the vehicle width direction. In a left-hand drive vehicle, the left-handed car corresponds to a compartment portion of a dash lower or a floor panel on the left foot side of the wheel arch shape. The low strength portion at the rear of the reinforcement frame means the joint portion (per the joint portion between the diagonal brace and the reinforcement frame coupled to the side sill in FIG. 1) if the reinforcement frame is divided back and forth, the positioning of the press work Or a hole for draining the electrodeposition paint (a hole on the upper surface of the reinforcing frame in FIG. 1) or the like.
In the configuration in which the strength is increased by increasing the thickness of the reinforcing frame or increasing the number of reinforcing members in order to reduce the amount of deformation toward the lower limbs, the vehicle weight increases and the manufacturing cost increases. I will.
In addition, in the method of reinforcing weak points one after another, there is a possibility that deformation more than expected may occur at unexpected places.

The present invention has been made in view of the above-described points, and a vehicle body structure capable of absorbing a collision load by being deformed at an assumed location at the time of a vehicle collision, while suppressing an increase in vehicle weight and manufacturing cost. Intended to provide.

In order to achieve the above object, the present invention is directed to a dash panel which is disposed along a vehicle width direction and is formed of a plate-like member which divides a power chamber and a vehicle compartment, and continuous to a lower edge of the dash panel A floor panel consisting of a plate-like member constituting the floor of the room, a front side frame extending along the longitudinal direction of the vehicle on at least an outer plate surface facing the power chamber of the dash panel; A reinforcing frame extending along a vehicle longitudinal direction at least a part of which overlaps the front side frame on an inner plate surface facing the chamber, and a dash panel reinforcing member disposed on the inner plate surface facing the cabin. In the vehicle body structure, the reinforcement frame is disposed at the front end to the kick-up portion, and the dash panel reinforcement member is disposed at least along the inclined portion of the front side frame. With a front side frame reinforcement part, characterized in that it is set to the fragile portion with a predetermined interval between the front side frame reinforcement part of the reinforcing frame and the dash panel reinforcement member.

According to the present invention, it is possible to provide a vehicle body structure capable of absorbing a collision load by deforming at an assumed place at the time of a vehicle collision and suppressing an increase in vehicle weight and manufacturing cost.

It is a perspective view which shows the driver's seat part of the vehicle body in which the vehicle body structure which concerns on this embodiment is installed. It is the perspective view which looked at the vehicle body in which the vehicle body structure concerning this embodiment is installed from the undersurface side. FIG. 5 is a cross-sectional view taken along the line III-III of FIG. 4; It is a top view which shows the driver's seat part of the vehicle body in which the vehicle body structure which concerns on this embodiment is installed. It is a principal part front view which shows the tunnel part which concerns on this embodiment. It is the principal part perspective view seen from the compartment side which shows the structure which connects a side sill and a lower side dash | collar cross member. It is the principal part cross-sectional perspective view seen from the vehicle outer side which shows the structure which connects a side sill and a lower dash cross member. It is sectional drawing which shows a mode that a floor panel is attached. It is a top view which shows the driver's seat part of the vehicle body in which the vehicle body structure which concerns on this embodiment is installed. It is principal part sectional drawing which shows the driver's seat part of the vehicle body in which the vehicle body structure which concerns on this embodiment is installed.

Embodiments of the present invention will be described in detail with reference to the drawings as appropriate. The same reference numerals are given to the same components and redundant description will be omitted.

As shown in FIGS. 1 and 2, in a vehicle V provided with a vehicle body structure 1 according to the present embodiment, a power chamber R1 in which a power source such as an engine is accommodated is set at the front of the vehicle body. In addition, a passenger compartment R2 in which a passenger gets on is adjacent to the passenger compartment.
In addition, the vehicle V includes a dash panel 10, a floor panel 20, side sills 30, a tunnel member 40, a front side frame 50, a reinforcing frame 60, a sub frame 70, and a dash panel reinforcing member 80.
In addition, since the vehicle body structure 1 is formed substantially symmetrically, in the following description, it demonstrates centering on the structure of the left side (driver's seat side).

As shown in FIGS. 1 to 3, the dash panel 10 is formed of a plate-like member formed into a predetermined shape by press processing or the like, and divides the power chamber R1 and the vehicle chamber R2 and is a front end of the vehicle chamber R2. Form a part.
Further, the dash panel 10 includes a front plate portion 11, an inclined portion 12, a floor plate portion 13, a wheel house portion 14, and a notch portion 15.

The front plate portion 11 extends in the vehicle vertical direction and in the vehicle width direction such that the plate surface faces in the vehicle longitudinal direction.
The inclined portion 12 is inclined downward from the lower end of the front plate portion 11 toward the rear of the vehicle, and extends to the height of the floor surface of the passenger compartment R2.
The floor plate portion 13 extends substantially horizontally rearward from the lower end (rear end) of the inclined portion 12, and constitutes a part of the floor surface of the vehicle compartment R2. Further, the floor panel 20 is joined to the rear end portion of the floor plate portion 13. Here, the bent portion between the inclined portion 12 and the floor plate portion 13 is referred to as a kickup portion.

As shown in FIG. 4, the wheel house unit 14 is set at both ends in the vehicle width direction of the dash panel 10, and is one of the wheel houses (not shown) covering the upper half of the front wheel (not shown) of the vehicle V. Make up the department. Further, the wheel house portion 14 is formed in a spherical shape that bulges toward the vehicle compartment R2 side so as to straddle the front plate portion 11 and the inclined portion 12, and is a vehicle body portion close to the lower leg.
The notch 15 is a U-shaped notch that opens downward at the center of the dash panel 10 in the vehicle width direction, and is formed across the front plate 11, the inclined portion 12, and the floor plate 13. . And the tunnel member 40 mentioned later is joined to the notch part 15. As shown in FIG.

The floor panel 20 is formed of a plate-like member formed into a predetermined shape by press processing or the like, and constitutes a floor surface of the compartment R2. Further, in the floor panel 20, a side sill 30 extends along the longitudinal direction of the vehicle at an outer end edge in the vehicle width direction. Furthermore, in the floor panel 20, a tunnel member 40 extends in the vehicle longitudinal direction at a central portion in the vehicle width direction. In the floor panel 20, a reinforcing frame 60 extends along the vehicle longitudinal direction on a plate surface on the vehicle compartment R2 side located between the side sill 30 and the tunnel member 40 in the vehicle width direction.
The side sill 30 is an inner member, and is formed of a hollow member having a rectangular tube shape extended in the vehicle longitudinal direction together with an outer member (not shown). And the side sill 30 comprises the side edge part in the floor surface of compartment R2. Further, the front end portion of the side sill 30 is joined to the end (left and right ends) of the dash panel 10 in the vehicle width direction.

As shown in FIGS. 1, 2, and 5, the tunnel member 40 is extended at the center in the vehicle width direction of the floor panel 20 along the vehicle longitudinal direction.
Further, the tunnel member 40 is opened downward by the top plate portion 41 extending along the vehicle width direction and a pair of side wall portions 42 extending downward from both end edges of the top plate portion 41 in the vehicle width direction. The groove has a substantially U-shaped cross section.
Furthermore, the tunnel member 40 is configured of a front side tunnel 40F and a rear side tunnel 40R.

The front side tunnel 40F is inclined so that the top plate portion 41 is positioned lower toward the rear, and forms a groove shape (U-shaped groove) with the pair of side wall portions 42.
Further, in the front tunnel 40F, a tunnel brace 43 is provided at a central portion in the vehicle longitudinal direction.
The tunnel brace 43 is a structure for preventing an increase in the distance between the opening edges of the U-shaped groove. The tunnel brace 43 is composed of a top plate bead portion 44 formed on the top plate portion 41 and a brace member 45 disposed in the U-shaped groove of the front side tunnel 40F.
The top bead portion 44 extends in the vehicle width direction at a central portion in the front-rear direction of the top plate portion 41 of the front side tunnel 40F, and is formed of a protrusion having a U-shaped cross section convex toward the compartment R2 side. .
The brace member 45 is a member obtained by bending a strip-shaped plate material into a U-shape in accordance with the inner surface shape of the U-shaped groove of the front side tunnel 40F, and installed at a position overlapping the top plate bead portion 44 in the U-shaped groove It is done.
Also, the brace member 45 is provided with a brace bead portion 46.
The brace bead portion 46 extends from one side wall portion 42 through the top plate portion 41 to the other side wall portion 42 at the central portion in the width direction of the strip-like plate material, and has a convex cross section opposite to the vehicle compartment R2. It is comprised by the protrusion which has a U-shape. The top plate bead portion 44 and the brace bead portion 46 form a closed space.

The rear side tunnel 40R is continuous with the rear side of the front side tunnel 40F, and the top plate portion 41 has a substantially horizontal U-shaped groove shape along the longitudinal direction of the vehicle. Then, on the front end edge of the top plate portion 41 and on the front end edges of the pair of side wall portions 42, flange portions (not shown) extending outward from the inside of the groove shape are formed. It is joined to the notch 15. Further, a flange portion extending in the vehicle width direction from the groove-shaped opening edge portion (lower end edge of the side wall portion 42) is joined to the left and right floor panels 20.
A propeller shaft (not shown), an exhaust pipe (not shown) and the like are accommodated in the groove of the tunnel member 40.

The front side frame 50 is configured by a pair of members as shown in FIGS. 1 and 2. Each front side frame 50 is extended so as to be substantially parallel to each other along the vehicle longitudinal direction while sandwiching the tunnel member 40 on the plate surface on the power chamber R1 side from the dash panel 10 to the floor panel 20 ing.
Each front side frame 50 further includes a support arm 51 and a bending portion 52.
The support arm portion 51 is formed of a hollow skeleton member formed in a substantially square cylindrical shape, and is disposed horizontally along the vehicle longitudinal direction in the power chamber R1, and a power source device (such as an engine) Support).
The bending portion 52 is continuously formed from the rear end of the support arm 51 to the kick-up portion, extends over the dash panel 10 and the floor panel 20, and on the outer surface FR1 facing the power chamber R1, It extends along the direction. In addition, the bending portion 52 has a groove shape having a substantially U-shaped cross section that opens toward the outer surface FR1 facing the power chamber R1 over the dash panel 10 and the front end portion of the floor panel 20. A flange portion 52a extending in the vehicle width direction from the opening edge portion is joined to the outer plate surface FR1. And the bending part 52 forms the closed cross section of the cross-sectional square shape with outer-plate surface FR1.
The bending portion 52 also includes a mounting bracket 53 and reinforcing stiffeners 54 and 55 (see FIG. 3).

The mounting bracket 53 is a bracket for supporting the sub frame 70, and is installed on the opposite side (power chamber R1 side) of a dash panel reinforcing member 80 described later with the dash panel 10 interposed therebetween.
The sub-frame 70, together with the support arm 51, supports the power source device. Then, when a load (collision load) equal to or greater than a set value is applied to the sub-frame 70 at the time of a collision, the sub-frame 70 separates from the mounting bracket 53 and separates the power source device from the vehicle V.
The reinforcing

stiffeners

54 and 55 are disposed in the groove of the bending portion 52 located on the opposite side of the portion where the flange portion 85a described later is disposed, with the dash panel 10 interposed therebetween. The reinforcing

stiffeners

54 and 55 are joined to the groove-shaped side walls and the bottom wall in the groove of the bending portion 52.
That is, the dash panel reinforcing member 80 and the mounting bracket 53 are disposed to face each other, the reinforcing

stiffeners

54 and 55 are disposed between the opposing flanges, and a rectangular parallelepiped closed space is formed in the bending portion 52. .

As shown in FIG. 1, FIG. 3 and FIG. 4, the reinforcing frame 60 extends over the kick-up portion of the dash panel 10 and the floor panel 20, and an inner plate surface FR2 facing the passenger compartment R2 along the vehicle longitudinal direction. Extends upwards. Further, the reinforcing frame 60 has a groove shape having a substantially U-shaped cross section in which the reinforcing frame main body 61 opens downward facing the floor panel 20, and through the flange portion 62 protruding in the vehicle width direction from the opening edge portion. , Is joined to the floor panel 20.
The reinforcing frame 60 is disposed at a predetermined distance from the dash panel reinforcing member 80 while its front end portion overlaps the rear end portion of the front side frame 50 in a top view.
In the reinforcing frame 60, the position in the vehicle longitudinal direction of the front end portion (the end portion on the side close to the fragile portion 17) is substantially the same as the position in the vehicle longitudinal direction of the front end portion (the end portion on the dash panel 10) of the side sill 30 It arrange | positions to correspond (refer auxiliary line L1 of FIG. 4).

And, the portion between the dash panel reinforcing member 80 and the reinforcing frame 60 in the dash panel 10 and the front side frame 50 has a weaker portion 17 whose strength is lower than that of the other portions. Is set to the area to be deformed.
Furthermore, the cross-sectional area of the cross section facing the vehicle longitudinal direction at the overlapping portion of the front end portion of the reinforcing frame 60 and the rear end portion of the front side frame 50 is smaller than the cross-sectional area of each other portion. It is set.
In addition, the sum of the cross-sectional area of the closed cross-section formed by the front side frame 50 and the dash panel 10 and the cross-sectional area of the closed cross-section formed by the reinforcing frame 60 and the dash panel 10 is the vehicle longitudinal direction. Each groove shape (height dimension) changes smoothly so as to be substantially constant along the

Dash panel reinforcing member 80 is, as shown in FIG. 4, a plurality of reinforcing members (center vertical frame 81, upper cross member 82, brake master cylinder mounting bracket 83, and the like) disposed on inner surface FR2 of dash panel 10. Dash cross member 84 and lower dash cross member 85).
The center vertical frame 81 is composed of a pair of left and right members arranged with the tunnel member 40 interposed therebetween, and on the extension line L2 of the ridge line portion which becomes the boundary between the top plate portion 41 of the tunnel member 40 and the pair of side wall portions 42 In the vertical direction of the vehicle, they are disposed in parallel on the plate surface of the vehicle compartment R2 of the front plate portion 11.
The center vertical frame 81 has a groove shape having an approximately U-shaped cross section that opens forward facing the front plate portion 11, and the dash panel 10 is provided with the flange portion 81a extending in the vehicle width direction from the opening edge portion. It is joined.

The upper cross member 82 is formed of a pair of left and right members disposed so as to sandwich the tunnel member 40, and is an extension line L3 of a ridgeline portion which is a boundary between the front end edge of the top plate portion 41 of the front side tunnel 40F and the front plate portion 11. It is disposed on the vehicle compartment R2 side plate surface of the front plate portion 11 on the upper side (in the vehicle width direction).
The upper cross member 82 has a groove shape having an approximately U-shaped cross section that opens forward facing the front plate portion 11, and is joined to the dash panel 10 via a flange portion 82a that protrudes in the vertical direction from the opening edge portion. It is done.
The brake master cylinder mounting bracket 83 is located at the front end side extension (in the longitudinal direction of the vehicle) of the reinforcing frame 60 on the driver's seat side, and is connected to the outer end portion of the upper cross member 82 in the vehicle width direction. It is disposed on the side plate surface of the passenger compartment R2.

The upper dash cross member 84 is formed of a pair of left and right members disposed across the tunnel member 40, and a vehicle compartment R2 whose end on the inner side in the vehicle width direction is a boundary portion between the front plate portion 11 and the inclined portion 12 It is located on the side plate surface and adjacent to the lower side of the brake master cylinder mounting bracket 83.
The upper dash cross member 84 is located on the wheel house 14 from the boundary between the front plate 11 and the slope 12 as it goes outward in the vehicle width direction.
Then, the upper dash cross member 84 has a groove shape having a substantially U-shaped cross section that opens forward facing the dash panel 10, and the dash panel 10 through the flange portion 84a protruding vertically from the opening edge portion. Bonded to.

The lower dash cross member 85 is composed of a pair of left and right members arranged to sandwich the tunnel member 40, and extends from the side sill 30 to the front tunnel 40F along the vehicle width direction on the cabin R2 side plate surface of the dash panel 10. It is arranged. The lower dash cross member 85 is located below (rear) of the upper dash cross member 84 and extends along the boundary between the wheel house portion 14 and the inclined portion 12 in the vehicle width direction on the inclined portion 12. Exist.
The lower dash cross member 85 has a groove shape having a substantially L-shaped cross section that opens forward facing the dash panel 10, and is joined to the dash panel 10 via a flange portion 85a protruding vertically from the opening edge portion It is done. The lower dash cross member 85 is provided with an outer flange portion 85b at an outer end in the vehicle width direction, and an inner flange portion 85c at an inner end in the vehicle width direction.

As shown in FIGS. 6 and 7, the outer flange portion 85 b is configured by a section bent from the L-shaped vertical wall portion to the rear of the vehicle. The outer flange portion 85 b is inserted from the front end of the side sill 30 into the cylinder of the side sill 30 and joined to the inner surface of the end portion of the side sill 30.
The inner flange portion 85c is formed of a L-shaped outwardly overhanging section. The inner flange portion 85c is joined to the portion of the side wall portion 42 where the tunnel brace 43 of the front side tunnel 40F is installed.
That is, the lower dash cross member 85 on the driver's seat side and the lower dash cross member 85 on the passenger seat side connect the side sills 30 on the left and right sides with the tunnel brace 43 interposed therebetween.

The lower dash cross member 85 is provided with a bridge portion 85 d extending upward (forward) so as to overlap the upper cross member 82 at a position overlapping the front side frame 50 when viewed from above.
Therefore, along the front side frame 50, the brake master cylinder mounting bracket 83, the upper dash cross member 84, the bridge portion 85d, and the lower dash cross member 85 continue from the front (upper) to the rear (lower) and are fragile. The reinforcing frame 60 further extends through the portion 17.
That is, on the dash panel 10 in which the front side frame 50 extends and on the compartment R2 side plate surface of the portion in the floor panel 20, reinforcing members are disposed except for the fragile portion 17.

As shown in FIG. 8, the dash panel reinforcing member 80 combines the above-described respective reinforcing members to constitute a wheelhouse reinforcing portion 80A, a front side frame reinforcing portion 80B, and a reinforcing portion 80C around a steering shaft opening.
The wheelhouse reinforcing portion 80A is formed of a rectangular area surrounded by upper and lower dash cross members. And wheel house reinforcement part 80A generates reaction force in the case of narrow offset collision A (small overlap collision).
The front side frame reinforcing portion 80B is formed at least on the brake master cylinder mounting bracket 83 and the upper and lower dash cross members on the cabin R2 side plate surface of the dash panel 10 and the floor panel 20 where the front side frame 50 extends. One part is arranged. Then, the front side frame reinforcing portion 80B generates a reaction force against an external force applied to the front side frame of the full flat front collision B.
The reinforcing portion 80C around the opening of the steering shaft is formed of a rectangular area surrounded by the upper and lower dash cross members, the brake master cylinder mounting bracket 83, the upper cross member 82, the center longitudinal frame 81, and the tunnel brace 43.
The reinforcing portion 80C around the opening of the steering shaft generates a reaction force at C when the power source device retracts in the power chamber R1 and collides with the dash panel 10 due to a collision.

Next, an operation at the time of a front collision of the vehicle body structure 1 according to the present embodiment will be described with reference to FIG.
A collision load is input to the front side frame 50 and the sub frame 70 by an offset collision, a front collision such as a full flat front collision, and a collision of these forms.
When the magnitude of the collision load input to the front side frame 50 and the sub frame 70 is equal to or greater than the set value, the sub frame 70 is separated from the frame, and the front side frame 50 is the fragile portion 17 (a no area). It bends around.

The collision load input to the front side frame 50 acts as a load that presses the front plate portion 11 of the dash panel 10 rearward via the support arm 51.

At this time, when the input collision load is smaller than a predetermined value, the front side frame 50 and the dash panel 10 are restored to the shape before the collision after elastic deformation such as bending. However, when the collision load to be input is larger than a predetermined value, the front side frame 50 and the dash panel 10 are bent at the fragile portion 17 whose strength is lower than that of the other portions, and are deformed into the shape of the code 50A.
Also, if the collision load input to the sub-frame 70 exceeds a predetermined value other than the aforementioned one, the sub-frame 70 is detached from the mounting bracket 53.

The vehicle body structure 1 of the present embodiment configured as described above can achieve the following effects.

In the vehicle body structure 1 of the present embodiment, the reinforcing frame 60 is disposed at a predetermined distance from the lower dash cross member 85 (the front side frame reinforcing portion 80B of the dash panel reinforcing member 80). Then, the portion between the dash panel 10 and the front side frame 50 between the dash panel 10 and the reinforcing frame 60 is set as the fragile portion 17 whose strength is lower than that of the other portions.
As a result, when the vehicle V collides and a collision load is input to the front side frame 50 and the dash panel 10, the front side frame 50 and the dash panel 10 bend at the fragile portion 17 and the rear kickup portion It is possible to reduce the amount of deformation of the vehicle compartment (wheel house part) to the lower limbs by reducing the turning radius than bending deformation.
In addition, since the reinforcing member is not newly added to set the fragile portion 17, the vehicle weight and the manufacturing cost are not increased.

Further, in the vehicle body structure 1 of the present embodiment, the cross-sectional area of the cross section of the reinforcing frame 60 and the front side frame 50 facing each other in the vehicle longitudinal direction at the overlapping portion is set smaller than the other portions.
As a result, the reinforcement frame 60 can be reduced in weight and deformed by the fragile portion 17 while securing sufficient rigidity against a collision load in the front-rear direction.

Furthermore, in the vehicle body structure 1 of the present embodiment, the lower dash cross member 85 (the dash panel reinforcing member 80) is disposed on the dash panel 10 via the provided flange portion 85a. Further, on the front side frame 50, reinforcing

stiffeners

54 and 55 are provided on the opposite side of the portion where the flange portion 85a is disposed with the dash panel 10 interposed therebetween.
Thereby, the rigidity of the periphery of the dash panel 10 of the fragile portion 17 can be enhanced. Then, the rigidity difference between the fragile portion 17 and the periphery thereof becomes large, so that the fragile portion 17 can be more reliably deformed by the collision load when the vehicle V collides.

In the vehicle body structure 1 of the present embodiment, the front side frame 50 is provided with a mounting bracket 53 for supporting the sub frame 70 at a portion facing the lower dash cross member 85 (the dash panel reinforcing member 80) with the dash panel 10 interposed therebetween. ing.
By supporting the sub-frame 70 on the mounting bracket 53, the collision load when the vehicle V collides is input from the front side frame 50 to the dash panel 10 via the sub-frame 70.
As a result, the collision load is dispersed and input to the dash panel 10 without being concentrated at one place, so deformation at the input portion is suppressed, and deformation can be made more reliably at the fragile portion 17.
Further, since the collision load is input in the vicinity of the fragile portion 17, the deformable region between the input portion and the fragile portion 17 is reduced, and the deformation in the fragile portion 17 is performed more reliably. Can.

In the vehicle body structure 1 of the present embodiment, the lower dash cross member 85 (dash panel reinforcing member 80) has a groove shape having a substantially L-shaped cross section, and the dash panel via the flange portion 85a provided at the opening edge of the groove shape. Located on the 10th.
Therefore, a triangular closed cross section is formed by the lower dash cross member 85 (the dash panel reinforcing member 80) and the dash panel 10.
Accordingly, the lower dash cross member 85 (the dash panel reinforcing member 80) can be disposed in a smaller installation space, and stable rigidity can be exhibited regardless of the direction in which the collision load is input.

In the vehicle body structure 1 of the present embodiment, the reinforcing frame 60 has a front end portion (end close to the fragile portion 17) at a position in the vehicle longitudinal direction of the front end portion of the side sill 30 (end portion on the dash panel 10). It arrange | positions so that it may correspond substantially with the position of a vehicle front-back direction (refer auxiliary line L1 of FIG. 4).
Therefore, the rigidity of the fragile portion 17 around the floor panel 20 can be enhanced against a collision in the vehicle front-rear direction.
As a result, the rigidity difference between the fragile portion 17 and the periphery thereof is increased, and the fragile portion 17 can be more reliably deformed by the collision load when the vehicle V collides.

In the vehicle body structure 1 of the present embodiment, the lower dash cross member 85 (dash panel reinforcing member 80) has the outer flange portion 85b provided at the outer end in the vehicle width direction joined to the inner surface of the side sill 30, and the inner end in the vehicle width direction. The inner flange portion 85 c provided on the tunnel brace 43 is joined to the tunnel brace 43.
Thereby, the impact load input to the lower dash cross member 85 (the dash panel reinforcing member 80) is transmitted to the side sill 30 and the tunnel brace 43, so that the impact energy that can be absorbed by the dash panel reinforcing member 80 can be increased.
Further, as a result, the lower dash cross member 85 (the dash panel reinforcing member 80) is vulnerable because the impact load when the vehicle V collides is input to rotate about the front end portion of the side sill 30. The part 17 can be deformed more reliably.

In the vehicle body structure 1 of the present embodiment, the dash panel reinforcing member 80 is configured of a plurality of reinforcing members, and each reinforcing member is disposed such that at least a portion thereof overlaps the front side frame 50.
This enables collision load absorption for full set full surface collisions and narrow offset collisions (small overlap collisions).

In the vehicle body structure 1 of the present embodiment, the dash panel 10 includes the floor plate portion 13, and the floor panel 20 is attached to the dash panel 10 via the floor plate portion 13.
Therefore, as shown in FIG. 10, the floor panel 20 can be attached to the dash panel 10 in a state where the dash panel reinforcing member 80 is attached to the dash panel 10 in advance.
As a result, the number of manufacturing steps can be reduced, productivity can be improved, and the fragile portion 17 can be easily set.

In the vehicle body structure 1 of the present embodiment, the sum of the cross-sectional area of the closed cross-section formed by the front side frame 50 and the dash panel 10 and the cross-sectional area of the closed cross-section formed by the reinforcing frame 60 and the dash panel 10 Each groove shape changes smoothly so as to be substantially constant along the longitudinal direction of the vehicle.
For this reason, variation in rigidity in the vehicle longitudinal direction can be reduced from the front side frame 50 to the reinforcing frame 60.
This makes it possible to clarify the difference in rigidity between the fragile portion and the other portion, so that the fragile portion 17 can be more reliably deformed when a collision load is input.
The front side frame reinforcing portion 80B may be a reinforcing plate disposed on the indoor side of the dash panel along the front side frame. In addition to the upper dash cross member 84, the lower dash cross member 85, and the bridge portion 85d in the embodiment, the bridge portion 85d may be extended from the lower side of the brake master cylinder mounting bracket 83.

Reference Signs List 1 vehicle body structure 10 dash panel 12 inclined portion 13 floor plate portion 17 fragile portion 20 floor panel 30 side sill 40 tunnel member 43 tunnel brace 50 front side frame 52a flange portion 53 mounting

bracket

54, 55 reinforcement stiffener 60 reinforcement frame 62 flange portion 70 subframe 80 dash panel reinforcing member 85a flange portion 85b outer flange portion 85c inner flange portion FR1 outer plate surface FR2 inner plate surface R1 power chamber R2 compartment

Claims

A dash panel formed of a plate-like member disposed along the vehicle width direction and defining a power room and a vehicle room;
A floor panel consisting of a plate-like member continuous with the lower edge of the dash panel and constituting a floor surface of the cabin;
A front side frame extending along the longitudinal direction of the vehicle on at least an outer surface of the dash panel facing the power chamber;
A reinforcing frame extending along the longitudinal direction of the vehicle at least a portion of which overlaps the front side frame on at least an inner plate surface facing the cabin of the floor panel;
A dash panel reinforcing member on an inner plate surface facing the casing;
In the body structure provided with
The reinforcing frame is disposed with the front end up to the kickup portion,
The dash panel reinforcing member includes a front side frame reinforcing portion disposed along at least an inclined portion of the front side frame, and a predetermined space is formed between the reinforcing frame and the front side frame reinforcing portion of the dash panel reinforcing member. A vehicle body structure characterized by being spaced apart and set in a fragile portion.
The reinforcing frame and the front side frame are
The vehicle body structure according to claim 1, wherein the cross-sectional area of the cross section facing the vehicle front-rear direction of the overlapping portion is set smaller than each other portion.
The dash panel reinforcing member is
Disposed on the dash panel via a provided flange portion,
The front side frame is
The vehicle body structure according to claim 1, further comprising reinforcing stiffeners on the opposite side of the portion where the flange portion is disposed with the dash panel interposed therebetween.
The front side frame is
A mounting bracket is provided at a portion facing the dash panel reinforcing member with the dash panel interposed therebetween,
The mounting bracket is
4. The vehicle body structure according to claim 3, wherein a sub-frame extending along a longitudinal direction of the vehicle is supported by the power chamber.
The dash panel reinforcing member is
It has a groove shape with a substantially L-shaped cross section,
The vehicle body structure according to claim 1, wherein the vehicle body structure is disposed on the dash panel via a flange portion provided at a groove-shaped opening edge.
The floor panel is
A side sill extending along the longitudinal direction of the vehicle is provided at an edge portion in the lateral direction of the vehicle,
The reinforcing frame is
The vehicle body according to claim 1, wherein a position in a vehicle longitudinal direction of an end on a side close to the fragile portion substantially coincides with a position in a vehicle longitudinal direction of an end on the dash panel side of the side sill. Construction.
A tunnel member having a groove shape opened downward along the longitudinal direction of the vehicle is provided at a central portion in the vehicle width direction of the dash panel,
The tunnel member comprises a tunnel brace that bends in a corrugated manner;
The dash panel reinforcing member is
An outer flange portion provided at an outer end in the vehicle width direction is joined to the inner surface of the side sill,
The vehicle body structure according to claim 6, wherein an inner flange portion provided at an inner end in the vehicle width direction is joined to the tunnel brace.
The dash panel reinforcing member is
Composed of multiple reinforcement members,
The vehicle body structure according to claim 1, wherein the reinforcing member is disposed so that at least a part thereof overlaps the front side frame.
The dash panel is
An inclined portion which inclines downward from the power chamber side toward the compartment side;
A floor plate extending substantially horizontally from the inclined portion;
The vehicle body structure according to claim 1, wherein the vehicle body structure is connected to the floor panel via the floor plate portion.
The front side frame is
It has a groove shape opened to face the dash panel,
The reinforcing frame is
It has a groove shape that opens toward the dash panel,
The sum of the cross-sectional area of the closed cross-section formed by the front side frame and the dash panel and the cross-sectional area of the closed cross-section formed by the reinforcing frame and the dash panel is substantially constant along the vehicle longitudinal direction. The vehicle body structure according to claim 1, wherein each groove shape changes smoothly so that