JPH07165118A - Torque box part structure of vehicle body - Google Patents

Abstract

PURPOSE:To improve the bending rigidity and reduce the weight by extending downward a part of a flange for connecting a front side member to a dash panel where the engine room side covered with a torque box part, and fixing the lower end of the extended part to a floor part in the torque box to form a flange supporting part. CONSTITUTION:An outer edge of a part of a flange 14a where the engine room side is covered with a torque box 17 of a flange to be welded to a dash under panel 15a to be formed at a rear part 14 of a front side member 12 is extended downward. A lower flange 14c is formed in the extended part to be connected to the surface of a floor member 16 inside the torque box part 17. This constitution forms a flange supporting part 14b on a part to connect the flange part 14a to the floor member 16 side to improve the bending rigidity of the flange part 14a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dash panel which is formed on the rear portion of a front side member and which is covered with a torque box on the engine room side of the flange for coupling to the dash panel. The present invention relates to a structure of a torque box portion of a vehicle body having a portion where it is difficult to connect work such as welding because it is covered with a so-called bag structure.

[0002]

2. Description of the Related Art In the chassis of a monocoque body,
Rocker parts that are the skeleton of the car body are arranged parallel to the center line of the car body on both the left and right outside of the floor under the car body, and the front side members are arranged parallel to the center line of the car body inside the tire house at the front of the car body. A torque box portion is provided on the engine room side of the lower part of the dash panel so as to connect the rocker portion and the front side member together, thereby increasing the rigidity of the rear portion of the front side member. (See Japanese Utility Model Laid-Open No. 62-49488).

FIG. 5 shows an example of the structure of a conventional torque box part having a structure which is a bag structure. The front side member 2 is provided in the engine room at the front of the vehicle body.
The front part 3 of the front part 3 is arranged substantially horizontally.
The rear portion 4 continuous to the rear side of the vehicle body is welded to a dash panel 5 provided so as to define an engine room and a vehicle compartment, and the rear portion 4 continuous to the rear of the front portion 3 is It extends downward along the dash panel 5 and extends under the lower end of the dash panel 5 toward the inside of the vehicle,
It is arranged on the lower surface side of the floor member 6.

Then, the dash under panel 5a is formed by inclining the lower part of the dash panel 5 and projecting to the inside of the vehicle.
On the engine room side, a torque box 7 is formed by bending a steel plate into a substantially trapezoidal cross section and opening the lower bottom part of the steel plate. Welding flanges 7a, 7a formed on the edge of the bottom portion are attached by welding to the lower surface of the dash under panel 5a. Further, one end (the right end in FIG. 5) of this torque box portion 7 is welded to the side surface of the rocker portion 8 on the outside of the vehicle body, and the other end is welded to the side surface of the rear portion 4 of the front side member 2 and its welding flange 7b. , 7b are welded and the front side member 2 and the rocker portion 8 are connected to each other, whereby the rigidity of the front side member 2 is increased.

However, the torque box 7 welded to the lower surface of the dash panel 5 on the engine room side.
The welding flanges 7a, 7a and the welding flange 7c at the end on the rocker portion 8 side and the flange 4a on the rear portion 4 of the front side member 2 define the engine room side and the vehicle interior side. Since it is arranged on the engine room side of the dash panel 5, it is necessary to perform welding from either the engine room side or the vehicle interior side in order to weld each part.

[0006] As a method of performing welding in a non-pressurized state from one side without sandwiching the two welded materials to be welded from both sides by electrodes, there are, for example, arc welding and laser welding. However, the former arc welding has a problem that the welding range is wide and the productivity is not good, and the latter laser welding has a matching accuracy of overlapping members of ± 0.1 mm.
Since the front side member 2 and the torque box 5 are made of sheet metal, they are not suitable in reality, and in the past, work holes were formed in the dash under panel 5a that covers the inside of the torque box 7 in the passenger compartment. 9 was formed, and one electrode of the welding machine was inserted from this working hole to enable sandwiching of two materials to be welded from both sides, and ordinary spot welding was performed.

[0007]

Therefore, in the above-described conventional torque box portion structure, work for spot welding formed on the dash under panel 5a which is a part of the torque box portion 7 which should have a closed cross-sectional shape. The holes 9 reduce the strength, and it is necessary to use a thick steel plate for the dash under panel 5a in order to compensate for the reduction in strength. As a result, the weight increases and the cost increases.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a torque box structure for a vehicle body which can reduce the weight and cost of a dash panel by eliminating work holes for welding. I am trying.

[0009]

As a means for solving the above problems, the present invention is directed to the engine room side of the lower portion of the dash panel which is inclined and projected toward the vehicle interior side. Between the lower portion and the floor member, the dash panel and the floor member are connected to each other, and the rocker portion outside the vehicle body and the front side member on the vehicle body center side are connected to each other in a closed cross-sectional shape. In the torque box structure of a vehicle body, the torque box portion is formed into a triangular or polygonal cross section with the rear side of the vehicle body open, and the outer surface of the lower side thereof is fixed to a floor member, and a dash is formed at the edge of the open portion. A flange for connecting to the panel is provided, and a flange for connecting to the dash panel at the rear portion of the front side member is provided. The engine compartment side of the engine compartment side is extended downward and the lower end of the extended portion is fixed to a floor member in the torque box portion to form a flange support portion. I am trying.

[0010]

With the above structure, the torque box structure of the vehicle body has a structure in which a portion of the flange for connecting the front side member to the dash panel is covered with the torque box on the engine room side. Since the lower end of the extended portion is fixed to the floor member in the torque box portion to form a flange support portion, the bending rigidity of the flange portion is improved. Therefore, when the flange and the dash panel are welded by increasing the rigidity of the flange, it is possible to perform series spot welding by pressing both electrodes against one side surface of the dash panel on the vehicle interior side. The work holes required for the dash panel are not required, and the strength is not reduced due to the formation of the opening, so that the dash panel can be thinned.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the torque box structure of a vehicle body according to the present invention will be described below with reference to FIGS.

The engine room at the front of the vehicle body is partitioned by a dash panel 15 between the engine room at the rear and the inside of the vehicle interior. The front part 13 of the front side member 12 is arranged substantially horizontally in this engine room. The rear portion 14 that is provided and continues to the rear side of the vehicle body of the front portion 13 extends downward along a dash panel 15 and a dash under panel 15a below the dash panel 15 that extends to the inside of the vehicle compartment. The dash under panel 15a extends under the lower end of the dash under panel 15a, extends toward the vehicle interior, and is disposed on the lower surface side of the floor member 16.

On the engine room side of the dash under panel 15a which is inclined and protrudes toward the vehicle interior side, a steel plate is bent into a shape with a substantially trapezoidal cross section and one bottom side of the vehicle body rear side is opened. The formed torque box portion 17 has one lower side surface thereof fixed to the floor member 16 by welding or the like, and the welding flanges 17a and 17a formed at the edges of the opened portion are attached to the dash. It is attached by welding to the lower surface of the under panel 15a on the engine room side. Further, one end (the right end in FIG. 1) of the torque box portion 17 is welded to the side surface of the rocker portion 18 outside the vehicle body, and the other end is welded to the side surface of the rear portion 14 of the front side member 12. By welding the flanges 17b and 17b,
The front side member 12 and the rocker portion 18 are connected to each other.

As shown in FIG. 3, among the flanges for welding to the dash under panel 15a formed on the rear portion 14 of the front side member 12, the flange 14a whose engine room side is covered with the torque box 17 is shown. Is extended downward with its outer edge, and the lower flange 1 is formed at the lower end of the extended portion.
4c to the floor member 16 in the torque box portion 17
To the upper surface of the flange 14a by directly or indirectly through the bottom of the torque box 17.
And the floor member 16 side are connected to the flange support portion 14
b. Therefore, the bending rigidity of the portion of the flange 14a inside the torque box portion 17 is improved, and the structure is such that it can sufficiently withstand the load applied from above when the electrode of series spot welding is pressed.

When welding the welding flanges 17a and 17c of the torque box portion 17 and the flanges 14a and 14d of the rear portion 14 of the front side member 12 to the side surfaces of the dash under panel 15a on the engine room side, in particular, The rear portion 14 having an air bag structure in which the engine room side is covered by the torque box portion 17
When welding the flange 14a of the dash under panel 15a from the vehicle interior side to the portion where the flange 14a overlaps the back side of the dash under panel 15a by pressing and contacting the positive and negative electrodes of the welding machine to energize, the dash under panel 15a and the flange 14a The nuggets are formed at two points on the contact surface in the welding current circuit due to the contact resistance with the welding current circuit, thereby welding. In this series of spot welding, two overlapped work pieces are pressed from one direction, so that the two work pieces are in close contact with each other and a gap is prevented, so that high processing accuracy of each member is achieved. Is not needed.

Similarly, by adopting the series spot welding method, the welding flanges 17a, 17a
Also for c, spot welding can be performed from the vehicle interior side of the dash under panel 15a. In FIG. 1, reference numeral 19 is a front pillar, 20 is a bulge of the tire house toward the passenger compartment, 21 is an insertion hole for a steering column, and 22 is an insertion hole for a wire harness to an instrument panel portion.

Next, the operation of this embodiment configured as described above will be described. When a front side member 12 on which the power unit is mounted is subjected to an axial compressive load during a frontal collision of the vehicle, Although the front side member 12 tends to fall toward the outside or the inside of the vehicle body or tries to bend, one end of the front side member 12 is connected to the side surface of the rear side of the vehicle body outside and the other end is connected to the rocker portion 18 outside the vehicle body. The bending and falling are prevented by the torque box portion 17, axial compression deformation of the front side member 12 is secured, and a large load can be absorbed by the front side member 12 buckling in the axial direction.
In particular, in this embodiment, since the series spot welding is adopted as the welding method of the structure of the bag, the working time can be shortened as compared with the case of performing the usual spot welding performed by providing the working holes, and the dash panel 15 Since the work hole for spot welding is not required in the dash under panel 15a forming the closed cross-sectional shape of the lower torque box 17, it is possible to form a completely closed cross section without an opening portion. Even if the thickness is reduced to a certain thickness, a predetermined strength can be maintained and the weight of the dash under panel 15a can be reduced.

Further, as shown in FIG. 4, the torque box 17 is provided outside the flange support portion 14b extending outside the flange 14a of the rear portion 14 of the front side member.
A flange 14e is formed at a portion in contact with an upper surface of the flange box and is welded to the inner surface of the torque box 17 by a series spot welding method.
Since the flanges 14a, 14c, 14e are formed on the entire periphery of the torque box portion 17 and the flanges 14a, 14c, 14e are welded on the entire inner periphery of the torque box portion 17 having a closed cross section, the bulkhead in the torque box portion 17 is formed. The torque box portion 17 can be effectively reinforced. In FIG. 4, reference numeral 14f denotes a flange reinforcing portion, which is used when the flange 14e formed on the side of the flange supporting portion 14b is subjected to series spot welding from one side of the torque box portion 17 on the engine room side. It is provided so as to prevent 14e from being deformed by the applied pressure.

[0019]

As described above, in the torque box structure for a vehicle body of the present invention, the rocker portion outside the vehicle body and the rear portion of the front side member on the vehicle body center side are connected to each other in the lower portion of the dash panel. Of the flange for connecting the rear side of the front side member to the dash panel provided with the torque box portion, the portion covered by the torque box portion on the engine room side is extended downward and the lower end of the extended portion is Since it was fixed to the floor member in the torque box portion as the flange support portion, it is possible to perform series spot welding by pressurizing the flange and the dash panel, which are the structure of the bag, from the vehicle interior side,
Therefore, since the working hole is eliminated and the rigidity of the torque box portion is improved, the weight of the dash panel can be reduced and the time required for the welding work can be shortened.

[Brief description of drawings]

FIG. 1 is a perspective view of a front portion of a vehicle compartment showing an embodiment of a vehicle body torque box structure according to the present invention.

FIG. 2 is a perspective view showing a front side member and a torque box portion of the embodiment excluding a dash panel.

FIG. 3 is a perspective view showing a rear portion including a flange support portion of the front side member of this embodiment.

FIG. 4 is a perspective view showing another example of a rear portion.

FIG. 5 is a perspective view of a front portion of a vehicle compartment showing an example of a conventional torque box structure.

[Explanation of symbols]

 12 Front Side Member 14 Rear Part 14a Flange 14b Flange Support Part 15 Dash Panel 15a Dash Under Panel 16 Floor Part 17 Torque Box 18 Rocker Part

Claims (1)

[Claims] 1. A dash panel is connected to the dash panel and the floor member between the lower part of the dash panel and the floor member on the engine room side of the portion that is inclined and projected toward the vehicle interior side of the dash panel. In addition, in the structure of the torque box part of the vehicle body, which is provided in the closed cross-sectional shape so as to connect the rocker part on the outer side of the vehicle body and the front side member on the center side of the vehicle body, the torque box part opens on the rear side of the vehicle body. Is formed into a triangular or polygonal cross section, the outer surface on the lower side is fixed to the floor member, and a flange for connecting to the dash panel is provided at the edge of the open portion, and the rear portion of the front side member is provided. Of the flange for connecting to the dash panel, the engine room side is covered by the torque box part. The part that,
A structure for a torque box portion of a vehicle body, which extends downward and a lower end of the extended portion is fixed to a floor member in the torque box portion to form a flange support portion.