JP2002274437A - Car body lower part structure of automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a flange part in a section opposing to a tyre to obtain sufficient energy absorption effect. SOLUTION: A join face 30B which becomes a rear side face of a vehicle in a step part 30 in a rocker inner part 24 and a join face 32A which becomes a front side face of the vehicle in an inner fringe part 32 in the direction of vehicle width in a front wall part 20A in a rocker outer part 20 abut, and these join faces 30B and 32A are welded on one side by laser welding from a front side of the vehicle. Moreover, a join flange 18A in a reinforcement 18 is welded on a rear side face 24B of the vehicle in a front wall part 24A of the rocker inner part 24 on one side by laser welding from the front side of the vehicle. Consequently, a flange extending toward the direction of a front tyre (the front of the vehicle) is eliminated in each join part of the rocker inner part 24, the rocker outer part 20, and the reinforcement 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underbody structure of an automobile, and more particularly to an underbody structure of an automobile for reducing an impact applied to the body via a tire at the time of a collision.

[0002]

2. Description of the Related Art Conventionally, as a lower structure of a vehicle body of this kind, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 2-212280.

As shown in FIG. 6, in this vehicle lower body structure, a rocker (also referred to as a side sill) 72 extending in the vehicle front-rear direction is provided on both lower sides of a vehicle body 70, and a front end of the rocker 72 is provided. The front pillar 7
4 are erected. A dash panel 76 is joined to the inside of the front pillar 74 in the vehicle width direction. A front side member 78 extends on the side of the dash panel 76 in the vehicle front-rear direction, and the outer side surface of the front side member 78 and the rocker 72 and the front pillar 7 are provided.
4 is connected by a torque box 80. The front end of the rocker 72 is connected to the torque box 80.
The shock absorbing portion 82 projects forward from the front end face of the vehicle to the front of the vehicle. In the event of a collision, a shock applied to the vehicle body 70 via a tire is absorbed by compressive deformation of the shock absorbing portion 82.

[0004]

However, in this vehicle lower body structure, the front end of the shock absorbing portion 82 which faces the tire (not shown) in the vehicle front-rear direction,
The joint 82A has a flange extending in the tire direction. As a result, this joint 8 where the tire first contacts
In 2A, there is almost no shock absorbing effect, and there is a problem that a sufficient energy absorbing effect cannot be obtained.

The present invention has been made in consideration of the above-described circumstances, and has as its object to eliminate a flange portion at a portion facing a tire and to obtain a lower body structure of an automobile in which a sufficient energy absorbing effect can be obtained.

[0006]

According to the present invention, there is provided an underbody structure of an automobile having a vehicle body lower member having a joint at a position opposed to a tire in a longitudinal direction of the vehicle, the joint comprising: Is characterized in that the joining surfaces to be joined to each other are overlapped in the longitudinal direction of the vehicle body and are welded on one side.

[0007] Accordingly, by joining the joining surfaces to be joined to each other in the longitudinal direction of the vehicle body and performing one-side welding, a flange extending toward the tire direction is eliminated at the joining portion. As a result, the vehicle body lower member facing the tire in the vehicle longitudinal direction can be extended toward the tire by the amount of the missing flange. For this reason, the cross section of the vehicle body lower member is enlarged toward the tire,
Strength and rigidity are improved, and a sufficient energy absorbing effect can be obtained.

According to a second aspect of the present invention, there is provided the vehicle body lower structure according to the first aspect, further comprising a guide means for guiding a joint surface to be joined to each other at the joint portion to a predetermined joint position. .

Therefore, in addition to the contents described in claim 1, at the time of assembling before welding, the joining surfaces to be welded to each other at the joining portion are guided to a predetermined joining position by the guide means.
Workability during welding is improved.

According to a third aspect of the present invention, in the vehicle underbody structure of the first aspect, the peripheral member of the joint is smoothly connected to a portion facing the tire in the vehicle longitudinal direction by one-side welding. It is characterized by.

Therefore, in addition to the contents described in the first aspect, since there is no flange extending in the tire direction in the peripheral member of the joint, the flange can be extended toward the tire by the amount of the missing flange. For this reason, also in the peripheral member of the joining portion, the cross-sectional portion is enlarged toward the tire, the strength and rigidity are improved, and the energy absorbing effect is improved. In addition, since the contact portion with the tire is increased by the smooth connection, the stress concentration of the tire can be suppressed.

According to a fourth aspect of the present invention, in the vehicle underbody structure according to any one of the first to third aspects, the one-side welding of the joint is laser welding.

Therefore, in addition to the contents described in any one of the first to third aspects, the welding operation can be sped up by laser welding the joint.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a lower body structure of an automobile according to the present invention will be described with reference to FIGS.

In the drawings, an arrow FR indicates a forward direction of the vehicle, an arrow IN indicates an inward direction of the vehicle width, and an arrow UP indicates an upward direction of the vehicle.

As shown in FIG. 2, a rocker 10 as a vehicle body lower member extending in the vehicle front-rear direction is disposed on both sides in the vehicle width direction below the vehicle body. The rocker 10 is disposed at a position slightly below the center of rotation of the front tire 11 (see FIG. 1), and a front pillar 12 is provided upright on the upper surface of the front end. A recess 13 is formed in the front wall portion of the front pillar 12 facing the front tire 11 toward the rear of the vehicle, and the recess 13 has an arc shape along the outer periphery of the front tire 11. .

As shown in FIG. 3, the rocker 10 and the front pillar 12 are composed of an outer panel 14 which forms the outer portion of these members in the vehicle width direction, and an inner panel 16 which forms the inner portion of these members in the vehicle width direction. The outer panel 14 forms a rocker outer portion 20 and a front pillar outer portion 22. The inner panel 16 forms a rocker inner part 24 and a front pillar inner part 26, and the reinforcement 18 is disposed between the rocker outer part 20 and the rocker inner part 24.

As shown in FIG. 1, the rocker inner portion 24
A step portion 30 as a guide means is formed so as to protrude toward the front of the vehicle at an outer edge portion in the vehicle width direction of the front wall portion 24A of the front wall portion 24A. The inclined portion 30A is bent obliquely forward and outward. In addition, the joint surface 3 which is the vehicle rear side surface of the step portion 30
In FIG. 0B, a joint surface 32A serving as a vehicle front side surface of a vehicle width direction inner edge portion 32 in a front wall portion 20A of the rocker outer portion 20 is provided.
Are brought into contact with each other, and these joining surfaces 30B and 32B
A is one-side welded from the front side of the vehicle by laser welding.

On the other hand, a joint flange 18A is formed at the front edge of the reinforcement 18 toward the inside in the vehicle width direction, and the joint flange 18A is formed on the vehicle rear side surface 24B of the front wall portion 24A of the rocker inner portion 24. One side is welded by laser welding from the front side of the vehicle.

As shown in FIG. 3, the joint surface 30B and the joint surface 32A also extend to the front pillar outer portion 22 and the front pillar inner portion 26, respectively. On the other hand, a joining flange 26A formed at the rear end edge of the front pillar inner portion 26 and a joining flange 22A formed at the rear end edge of the front pillar outer portion 22
And a joining flange 26A formed at a lower end edge of the rocker outer portion 20 and a joining flange 24C formed at a lower end edge of the rocker inner portion 24.
And are welded.

A joining flange 18B is formed at the lower edge of the reinforcement 18, and the joining flange 18B is connected to the joining flange 20B formed at the lower edge of the rocker outer portion 20 and the lower edge of the rocker inner portion 24. Is welded to the joint flange 24C formed at the bottom. An upper wall 18C is formed on the upper edge of the front portion of the reinforcement 18 inward in the vehicle width direction. The inner edge of the upper wall 18C in the vehicle width direction is directed upward. Thus, a joining flange 18D is formed. This joining flange 18D is used for the inner panel 1
6 is welded to the outer surface 16A in the vehicle width direction. Also, an upper edge 18E at the rear of the reinforcement 18 is provided.
Is welded between a joint flange 20C formed on the upper edge of the rocker outer portion 20 and a joint flange 24D formed on the upper edge of the rocker inner portion 24.

As shown in FIG. 2, an inclined portion 40A of the front side member 40 is disposed at a predetermined interval inside the front end of the rocker 10 in the vehicle width direction. Inclined part 40 of front side member 40
A torque box 42 as a peripheral member is disposed between the torque box 42 and the torque box A.

As shown in FIG. 1, the torque box 42
A joint flange 42A is formed on the outer edge in the vehicle width direction toward the rear of the vehicle, and this joint flange 42A is one-side welded to the front edge of the inner side surface 24F in the vehicle width direction in the rocker inner portion 24 by laser welding. ing. Front surface 42B at the inner edge in the vehicle width direction of torque box 42
Is smooth along the front wall portion 24A of the rocker inner portion 24 and along the vehicle width direction (with respect to the front tire 11). Further, the torque box 42 is curved forward in the vehicle width direction, and a joint flange 42C is formed on the inner edge of the torque box 42 in the vehicle width direction toward the vehicle front. The joint flange 42C is welded to the front portion of the outer side wall portion 40B of the front side member 40 in the vehicle width direction.

A joining flange 40C is formed outwardly in the vehicle width direction at the rear edge of the outer side wall portion 40B of the front side member 40 in the vehicle width direction. A joining flange 40E is formed on the rear edge of 40D inward in the vehicle width direction. These joining flanges 40C, 40E
Is the front side member rear reinforcement 4
The front side member rear reinforcement 46 is welded to a dash panel 50 as a peripheral member.

A joining flange 50A is formed on the outer edge of the dash panel 50 in the vehicle width direction toward the rear of the vehicle, and the joining flange 50A is formed on one side of the inner side surface 24F of the rocker inner portion 24 by laser welding. Welded. As shown in FIG. 2, at a portion above the position where the torque box 42 is provided, the joining flange of the dash panel 50 is attached to the front edge of the front pillar inner portion 26 on the inner surface in the vehicle width direction by laser welding. The front surface 50B at the vehicle width direction inner edge of the dash panel 50 is smooth along the front wall portion 26B of the front pillar inner portion 26 along the vehicle width direction.

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

In the vehicle underbody structure of the present embodiment,
As shown in FIG. 1, a joint surface 30 serving as a vehicle rear side surface of a step portion 30 in a rocker inner portion 24 of an inner panel 16.
B and a joint surface 32A which is a vehicle front surface of the vehicle width direction inner edge portion 32 of the front wall portion 20A of the rocker outer portion 20 of the outer panel 14 is in contact with each other, and these joint surfaces 30B and 32A Are welded on one side by laser welding from the front side of the vehicle. The joining flange 18A of the reinforcement 18 is one-side welded to the rear wall 24B of the front wall 24A of the rocker inner portion 24 from the front side of the vehicle by laser welding.
For this reason, the rocker inner part 24, the rocker outer part 20,
There is no flange extending toward the front tire (front of the vehicle) at each joint of the reinforcement 18.

As a result, in the present embodiment, as compared with the lower body structure of the comparative example, which has a joining flange portion 90 at a position facing the front tire 11 in the front-rear direction of the vehicle body as shown by a solid line in FIG. As shown by the dashed line, the closed cross section S corresponds to the lost joint flange portion 90.
Can be extended to the front tire 11 side. For this reason, the cross section of the front end portion (lower end portion of the front pillar) of the rocker 10 is enlarged toward the front tire, and the strength and rigidity are improved. Therefore, as shown in FIG.
When the abutment comes into contact with the front end of the rocker 10, the front end of the rocker 10 extending forward is compressed and deformed, so that a sufficient energy absorbing effect can be obtained.

In this embodiment, as shown in FIG. 1, a stepped portion 30 as a guide means is formed on the outer edge of the front wall portion 24A of the rocker inner portion 24 in the vehicle width direction toward the front of the vehicle. The leading end of the step portion 30 is an inclined portion 30A that is bent obliquely forward and outward. As a result, at the time of assembling before welding, the stepped portion 30 having the inclined portion 30A can prevent the joining surface 30B and the joining surface 32A from being turned back and forth, and can prevent the joining surface 30B and the joining surface 32A from being reversed. Can be reliably and easily contacted. Therefore, workability at the time of welding is improved.

In this embodiment, as shown in FIG. 1, the joint flange 42A of the torque box 42 is connected to the front end of the inner side surface 24F in the vehicle width direction of the rocker inner portion 24 by laser welding. The front surface 42B at the inside edge portion of the vehicle width direction 42 is smooth along the front wall portion 24A of the rocker inner portion 24 along the vehicle width direction. Further, at a position above the position where the torque box 42 is provided, the joining flange of the dash panel 50 is one-side welded to the front edge of the front pillar inner portion 26 on the inner side surface in the vehicle width direction by laser welding. The front surface 50 </ b> B at the vehicle width direction inner edge of the panel 50 is the front wall 2 of the front pillar inner portion 26.
6B, which is smooth along the vehicle width direction. As a result,
Also in the torque box 42 and the dash panel 50, there is no flange extending toward the front tire, so that the cross section can be extended toward the tire by the amount of the missing flange. For this reason, also in the torque box 42 and the dash panel 50, the cross section is expanded to the front tire side, strength and rigidity are improved, and the energy absorbing effect is improved. In addition, since the contact portion with the front tire 11 increases in the vehicle width direction and the front of the vehicle due to the torque box 42 and the dash panel 50, the front tire 11 moves in the vehicle front-rear direction as shown by a two-dot chain line in FIG. Even when the vehicle inclines inward in the vehicle width direction, the contact area with the front tire 11 can be increased, and the stress concentration of the front tire 11 can be suppressed.

In this embodiment, since one-side welding of each joint is performed by laser welding, the speed of the welding operation can be increased.

In the above, the present invention has been described in detail with respect to a specific embodiment. However, the present invention is not limited to such an embodiment, and various other embodiments are included in the scope of the present invention. It is obvious to those skilled in the art that it is possible, for example, in the above embodiment, the joint was welded one side from one side by laser welding, but instead of laser welding, the joint was welded to one side by another welding method. May be welded from one side.

In the above embodiment, the lower body structure of the vehicle of the present invention is applied to the front end of the rocker 10 facing the front tire 11, but the lower body structure of the vehicle of the present invention is applied to the rocker facing the rear tire. It can be applied to other parts such as the rear end.

In the above embodiment, the torque box 42 and the dash panel 50 are connected by laser welding as the peripheral members. However, the peripheral members are not limited to the torque box 42 and the dash panel 50. good.

Further, in the above embodiment, the step portion 30 having the inclined portion 30A at the distal end portion is used as the guide means. However, the configuration of the guide means is not limited to this, and the joint surfaces to be joined to each other at the joint portion are formed in a predetermined manner. Any configuration may be used as long as it leads to the joining position.

[0036]

According to the first aspect of the present invention, there is provided an underbody structure of an automobile having a vehicle body lower member having a joint at a position opposed to a tire in the vehicle longitudinal direction, wherein the joints are joined to each other. Since the joining surfaces are overlapped in the front-rear direction of the vehicle body and welded on one side, the flange portion at the portion facing the tire is eliminated, and there is an excellent effect that a sufficient energy absorbing effect can be obtained.

According to a second aspect of the present invention, in the vehicle underbody structure of the first aspect, a guide means for guiding a joint surface to be joined to each other at a joint portion to a predetermined joint position is provided. In addition to the effect, it has an excellent effect that workability at the time of welding is improved.

According to a third aspect of the present invention, in the vehicle body lower part structure according to the first aspect, the peripheral members of the joint are formed by:
Since the tire is smoothly connected to a portion facing the tire in the longitudinal direction of the vehicle body by one-side welding, in addition to the effect described in the first aspect, there is an excellent effect that the energy absorption effect is improved and the stress concentration of the tire can be suppressed.

According to a fourth aspect of the present invention, in the vehicle body lower part structure according to any one of the first to third aspects, the one-side welding of the joint is performed by laser welding. In addition to the effects described in (1), there is an excellent effect that the welding operation can be speeded up.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along line 1-1 in FIG.

FIG. 2 is a perspective view showing a lower body structure of the vehicle according to an embodiment of the present invention, as viewed obliquely from the outside in front of the vehicle.

FIG. 3 is an exploded perspective view showing a main part of a lower body structure of the vehicle according to the embodiment of the present invention, as viewed obliquely from the front outside of the vehicle.

FIG. 4 is an operation explanatory view showing a vehicle body lower structure according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view corresponding to FIG. 1 and showing a lower body structure of an automobile of a comparative example.

FIG. 6 is a perspective view showing a lower body structure of an automobile of a conventional example, viewed from a diagonally outer front side of the vehicle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Rocker 11 Front tire 12 Front pillar 14 Outer panel 16 Inner panel 20 Rocker outer part of outer panel 22 Front pillar outer part of outer panel 24 Rocker inner part of inner panel 26 Front pillar inner part of inner panel 30 Step part (guide means) 30B Joining surface 32A Joint surface 42 Torque box (peripheral member) 50 Dash panel (peripheral member)

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Atsuhiko Murakami 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 3D003 AA01 AA05 AA12 BB01 CA05 CA17 CA33 CA53

Claims (4)

[Claims] 1. A lower body structure of an automobile having a vehicle body lower member having a joint at a position opposed to a tire in a vehicle longitudinal direction, wherein the joints overlap a joint surface to be joined to each other in a vehicle longitudinal direction. An underbody structure of an automobile characterized by being welded on one side. 2. The underbody structure of an automobile according to claim 1, further comprising guide means for guiding joining surfaces joined to each other at said joining portion to a predetermined joining position. 3. The lower body structure of an automobile according to claim 1, wherein the peripheral member of the joint is smoothly connected to a portion facing the tire in the vehicle longitudinal direction by one-side welding. 4. The underbody structure of an automobile according to claim 1, wherein the one-side welding of the joint is laser welding.