JP3123584B2 - Body front structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front frame structure of a vehicle body.

[0002]

2. Description of the Related Art As a conventional front frame structure of a vehicle body, for example, there is a structure as shown in FIGS. 7 to 10 (for a similar structure, see JP-A-61-115779).
In the following description, A indicates the front, B indicates the rear, C indicates the outside (with respect to the vehicle width center), and D indicates the inside (with respect to the vehicle width center).

[0003] A front side member 1 and a closing plate 2 are provided at the lower left and right sides of an engine room of an automobile.
And a skeleton member 3 having a closed cross-sectional structure consisting of
The rear end of the skeletal member 3 is connected to the dash lower 4 in a state of entering under the floor of the vehicle. A suspension bracket 5 for supporting a suspension member (not shown) is provided below the frame member 3.

[0004] Inside the frame member 3, a reinforcing plate 6 for increasing the rigidity of the frame member 3 is provided. An upward flange 6a is formed at the inner end of the reinforcing plate 6 in the front-rear direction, and the upward flange 6a is joined to the inner surface of the side surface 1a of the front side member 1. As described above, even if the upward flange 6a located inside the skeleton member 3 is formed in the front-back direction, the upward flange 6a can be attached to the side portion 1a of the front side member 1 before the closing plate 2 is joined to the front side member 1. The welding work is easy because it is welded to the inner surface of the steel.

[0005] The outer end of the reinforcing plate 6 has a rear upward flange 6b and a front horizontal outward flange 6b.
and c are continuously formed via the cut-out portion K. The rear upward flange 6b is welded to the closing plate 2 (not shown in cross section), and the front outward flange 6c is welded to the front side members 1 and the outward flanges 1b and 2a of the closing plate 2. The welding operation of the rear upward flange 6b can be performed by inserting a welding gun through the relatively large rear end opening 3a of the skeletal member 3, but the welding gun is inserted through the front opening of the skeletal member 3. Since it cannot be inserted to a very deep position, as described above, the front side of the outer end of the reinforcing plate 6 projects outward as an outward flange 6c,
The welding operation can be performed outside the frame member 3 together with the other outward flanges 1b and 2a.

[0006]

However, in such a conventional technique, at the outer end of the reinforcing plate 6, the rear side is an upward flange 6b and the front side is an outward flange 6c. The center of gravity (center of gravity) S is the upward flange 6b and the outward flange 6
It will be shifted at the turning portion K which is the boundary with c. Therefore, for example, when an external force F is applied to the skeletal member 3 from the front side, a moment in the lateral direction is generated by the external force F, and the skeletal member 3 moves from the position where the centroid S is shifted (that is, the turning back portion K) in the M direction. There is a risk of breaking.

[0007] Further, the bending of the skeleton member 3 is as follows.
Not only the shift of the centroid S but also the presence of the cut-back portion K itself is a cause. That is, since the strength at the outer end of the reinforcing plate 6 is partially reduced at the turning portion K, the turning portion K serves as a trigger, so that the skeleton member 3 is easily broken.

Further, since outward flanges 1b, 2a and 6c are formed on the front side of the frame member 3 so as to protrude to the side, respectively, the closing plate 2 and the tire T
It is necessary to form a sufficient gap L ₁ between, correspondingly, the cross-sectional area of the skeleton member 3 is reduced, skeletal member 3
Disadvantage in securing the strength of the steel.

As a countermeasure for solving the above-mentioned problems in strength, conventionally, the thickness of the members constituting the skeletal member 3 has been increased. However, to increase the weight, another strength countermeasure has been proposed. Is desired.

The present invention has been made by paying attention to such a conventional technique, and provides a vehicle body front structure capable of preventing a skeletal member from being broken and increasing a cross-sectional area of the skeletal member. Things.

[0011]

In order to achieve the above object, a front skeletal structure of a vehicle body according to the present invention is provided with an upwardly-facing flange and a downwardly-facing front side member having an outwardly opened cross-sectional shape. each joining the upper and lower corresponding portions of the closing plates to form a skeleton member of closed cross section, within the framework members, on the rear portion outer end
Turning flange and downward flange of front part
And the turned-back portion corresponding to the inner end formed continuously through
The inner surface of the side of the front side member
An upward flange to be joined to is formed ,
A reinforcing plate is provided in which the downward flange of the front portion is joined to the downward flange and the closing plate of the front side member, and the upward flange of the rear portion is joined to the closing plate. An upward flange which is formed on the outer surface of the side surface of the front side member, and which is directly or indirectly joined to the downward flange of the front portion of the reinforcing plate beyond the cutout at the outer end ,
Outward of the closing plate behind the notch
A suspension bracket provided with an outward flange to be joined to the flange is provided.

[0012]

According to the present invention, at the outer end of the reinforcing plate,
Since the upward flange of the rear portion and the downward flange of the front portion are continuously formed via the cut-out portion, the centroid of the reinforcing plate is straight across the front and back of the reinforcing plate and does not shift midway. Therefore, even when an external force is applied to the skeleton member in the front-rear direction, the skeleton member does not break.

Further, since the downward flange formed on the front side of the suspension bracket is directly or indirectly joined to the downward flange of the reinforcing plate beyond the turning portion, the strength of the turning portion is reduced by the downward flange of the suspension bracket. In addition, it is possible to reliably prevent the skeletal member from being broken from the turning portion.

Further, the portions of the front side member, the reinforcing plate, and the suspension bracket corresponding to the tire are downward flanges, and the gap between the closing plate and the tire can be reduced. Can be enlarged to increase the strength of the skeleton member.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described with reference to FIGS.
It will be described based on.

Hereinafter, each member will be described in order.

Front side member 7:

The front side member 7 has a substantially hat-shaped cross section having an upward flange 7a and a downward flange 7b. In addition, a rear end opening (an opening formed at the end when the skeleton member 8 is assembled finally) 8a
The inclined flange 7c joined to the dash lower panel (not shown) is formed at the side end corresponding to. Also,
The rearmost part of the front side member 7 is a downward flange 7b
Are omitted, and a suspension bracket 9 described later is used.
A notch 7d for avoiding multiple joining is also formed on the bottom surface of the portion to which is attached.

Closing plate 10:

The closing plate 10 has a substantially flat plate shape, and an inclined flange 10a is formed at a side end forming the rear end opening 8a. A partial outward flange 10b is formed at the lower end of the closing plate 10 corresponding to the suspension bracket 9, and a partial inward flange 10c is also formed at the lower end of the rearmost portion. The closing plate 10 and the front side member 7 form a frame member 8 having a closed cross section.

Reinforcing plate 11:

The reinforcing plate 11 has the same width corresponding to the bottom surface of the front side member 7 from front to back. On the inner end of the reinforcing plate 11, an upward flange 11a is formed over the front and rear, an upward flange 11b is formed on the rear side of the outer end, and a downward flange 11c is formed on the front side with a cut-out portion K. Are formed continuously. As described above, both the inner end and the outer end of the reinforcing plate 11 have the upward flanges 11a and 11b and the downward flange 11c, respectively.
Is formed, the width of the reinforcing plate 11 does not change in the middle. Therefore, the center of gravity S of the reinforcing plate 11 is straightened in the front and rear directions and does not shift midway (see FIG. 1). Further, a bead 11 d facing upward in the front-rear direction is formed on the bottom surface of the reinforcing plate 11 so as to straddle the turning portion K.

Suspension bracket 9:

The suspension bracket 9 has a bent shape in two steps, and a support hole 9a for supporting a suspension member is formed in a horizontal portion in the middle. A partial outward flange 9b is formed at the outer end of the portion where the support hole 9a is formed. An upward flange 9c is formed at the inner end of the suspension bracket 9, and downward flanges 9d and 9e are formed before and after the outer end. In particular, the reinforcing plate 11 has a downward flange 9e on the front side .
Downward flange 11 of reinforcing plate 11 in assembled state
One of the features is that it is formed to extend forward to a position where it reaches the rear end of c.

Assembly procedure

Next, the procedure for assembling these members will be described.

A) Front side member 7 + reinforcement play
To 11:

With the welding gun G, the upward flange 11a inside the reinforcing plate 11 is welded to the inner surface of the side surface 7e of the front side member 7, and the bottom surface of the reinforcing plate 11 is welded to the bottom surface of the front side member 7. Also,
The downward flange 11c of the outer end of the reinforcing plate 11 is
It is welded to the downward flange 7b of the front side member 7. The joining work between the two is easy before the front side member 7 and the closing plate 10 are joined.

B) The above A + closing plate 10:

The closing plate 10 is joined to the front side member 7 (A above) to which the reinforcing plate 11 is attached. That is, the upper end of the closing plate 10 is joined to the upward flange 7a of the front side member 7, and the lower end of the closing plate 10 is connected to the downward flange 11c and the upward flange 11b of the reinforcing plate 11, and the rear side of the front side member 7. To the downward flange 7b. Furthermore, closing plate 1
The inward flange 10c at the rear end of the front side member 7 is joined to the rearmost bottom surface of the front side member 7. The above-mentioned joining work is joining of parts projecting to the outside, or joining at a position close to the rear end opening 8a, so that welding work is easy. When the closing plate 10 is joined to the front side member 7, the frame member 8 is formed.

[0031]C) The B + suspension bracket
9:

[0032] on the inner end of the suspension bracket 9
Orientation flange 9c is attached to side 7 of front side member 7.
e. This operation is performed by inserting the welding gun G from the rear end opening 8a. Next, the downward flange 9d on the rear side of the outer end of the suspension bracket 9 is joined to the corresponding lower end of the closing plate 10, and the partial outward flange 9b formed in the middle is partially connected to the closing plate 10. To the lower surface of the front outward member 10b, and further, the front downward member 9e is connected to the lower flange 7b of the front side member 7.
And to the lower end of the closing plate 10.
The front downward flange 9e is joined to both the downward flange 7b (there is a downward flange 11c below) of the front side member 7 and the lower end of the closing plate 10 in a state of exceeding the cut-back portion K. Therefore, a small step (not shown) is formed in advance between the joint surface with the downward flange 7b of the front side member 7 and the joint surface with the closing plate 10 so that a step does not occur at the joint. When the suspension bracket 9 is attached to the lower side of the frame member 8, all the assembly operations are completed. In the assembled state, the outward flanges 9b and 10b joined to each other in the middle part of the suspension bracket 9 project outwardly, but this part is a position that is not affected by the tire T, and thus has a problem. Absent.

Next, the advantages of the structure of this embodiment will be described.

According to the structure of this embodiment, since the centroid S of the reinforcing plate 11 is straight in the front and rear direction and is not shifted in the middle, the reinforcing plate 11 itself is very hard to be broken. Therefore, even if an external force F is applied to the skeleton member 8 in the front-rear direction, the internal reinforcing plate 11 is hard to be broken, so that the whole skeleton member 8 is hard to be broken.

The downward flange 9e on the front side of the suspension bracket 9 is indirectly joined to the downward flange 11c of the reinforcing plate 11 via the downward flange 7b in a state in which the downward flange 9c extends beyond the notch K. Since the flange 9e compensates for the reduction in strength due to the turning portion K, the skeletal member 8 does not break due to the turning portion K of the reinforcing plate 11 as a trigger.

Since the beads 11d extending in the front-rear direction are formed on the bottom surface of the reinforcing plate 11, the frame members 8
And the skeletal member 8 is connected to the reinforcing plate 11.
It does not break due to the turning portion K.

Further, in the front portion of the frame member 8 corresponding to the position of the tire T, all the downward flanges 7b, 11c
Since that is the, possible to reduce the gap L ₂ between the closing plate 10 and the tire T, correspondingly, enlargement of the cross-sectional area of the skeleton member 8 is achieved. Therefore, the strength of the skeletal member 8 is improved by the increase in the cross-sectional area, and the frame member 8 is less likely to be broken even when subjected to an external force F in the front-rear direction.

In the above description, an example in which the front downward flange 9e of the suspension bracket 9 is joined "indirectly" to the downward flange 11c of the reinforcing plate 11 via the downward flange 7b of the front side member 7 is shown. However, the rear end of the downward flange 11c adjacent to the turning portion K of the reinforcing plate 11 is
, The front flange 9e of the suspension bracket 9 may be directly joined to the rear end of the downward flange 11c.

[0039]

The front skeletal structure of the vehicle body according to the present invention
As described above, since the upward flange of the rear portion and the downward flange of the front portion are continuously formed at the outer end of the reinforcing plate via the turning portion, the centroid of the reinforcing plate is formed. Is straightened around the front and back of the reinforcing plate, and does not shift midway. Therefore, even when an external force is applied to the skeleton member in the front-rear direction, the skeleton member does not break.

Further, since the downward flange formed on the front side of the suspension bracket is directly or indirectly joined to the downward flange of the reinforcing plate beyond the turning portion, the strength of the turning portion is reduced by the downward flange of the suspension bracket. In addition, it is possible to reliably prevent the skeletal member from being broken from the turning portion.

Furthermore, the portions of the front side member, the reinforcing plate, and the suspension bracket corresponding to the tire are downward flanges, and the gap between the closing plate and the tire can be reduced. Can be enlarged to increase the strength of the skeleton member.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a front frame structure of a vehicle body according to an embodiment of the present invention.

FIG. 2 is an assembly view of the structure of FIG.

FIG. 3 is a sectional view taken along the line SA-SA shown in FIG.

FIG. 4 is a sectional view taken along line SB-SB shown in FIG.

FIG. 5 is a cross-sectional view taken along the line SC-SC shown in FIG. 2;

FIG. 6 is a sectional view taken along line SD-SD shown in FIG.

FIG. 7 is a perspective view showing a conventional front frame structure of a vehicle body.

FIG. 8 is a perspective view showing a conventional reinforcing plate.

9 is a cross-sectional view of the skeleton member taken along line SE-SE shown in FIG.

FIG. 10 is a cross-sectional view of a skeleton member taken along line SF-SF shown in FIG.

[Explanation of symbols]

 Reference Signs List 7 Front side member 8 Frame member 9 Suspension bracket 10 Closing plate 11 Reinforcement plate 11d Bead K Turning part

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B62D 21/11 B62D 25/20

Claims (2)

(57) [Claims] 1. A closed cross section in which upper and lower corresponding portions of a closing plate (10) are joined to an upward flange (7a) and a downward flange (7b) of a front side member (7) having a cross-sectional shape opened outward. Forming a skeletal member (8) , wherein the rear end of the skeletal member (8) faces upward at the outer end.
The flange (11b) and the downward flange (11
c) are continuously formed through the cut-out portion (K), and flow around the inside end corresponding to the cut-out portion (K).
To the inner surface of the side (7e) of the side member (7).
And a downward flange (11c) of the front portion is joined to a downward flange (7b) and a closing plate (10) of the front side member (7) and the rear side portion is formed.
The upward flange (11b) is the closing plate
A reinforcing plate (11) to be joined to (10) is provided, and an upward flange (9c ) joined to an outer surface of a side portion (7e) of a front side member (7) at an inner end below the skeletal member (8). ) Is formed, and a notch is formed at the outer end.
And (K) a beyond reinforcing plate downward flange (9e) which is directly or indirectly joined to the front portion of the downward <br/>-out flange (11c) of (11), after the turning-back portion (K) ~ side
The outward flange (1) of the closing plate (10)
A front frame structure for a vehicle body, comprising a suspension bracket (9) provided with an outward flange (9b) joined to the front bracket ( 0b) . 2. A turning plate is provided on the bottom of the reinforcing plate (11).
Bead along the longitudinal direction with the straddle (K) straddling
The front frame structure of a vehicle body according to claim 1, wherein (11d) is formed.