JP6720857B2 - Body frame structure - Google Patents

Description

The present invention relates to a vehicle body frame structure.

Patent Document 1 discloses a structure in which a pair of side rails are connected by a cross member on a vehicle front side and a vehicle rear side of a bent portion formed on a side rail and bent outward in the vehicle width direction. In the structure disclosed in Patent Document 1, the connecting portion between the cross member on the vehicle front side and the vehicle front side of the bent portion is connected to the cross member on the vehicle rear side.

JP, 2014-213764, A

In the structure disclosed in Patent Document 1, the load acting on the vehicle body at the time of a head-on collision may increase and the deceleration may increase. In addition, there is room for improvement in suppressing the deformation of the vehicle body during a small lap collision.

In view of the above facts, it is an object of the present invention to provide a vehicle body skeletal structure capable of suppressing an increase in deceleration during a head-on collision and suppressing deformation on the side opposite to the collision side during a minute lap collision.

A vehicle body skeletal structure according to a first aspect of the present invention is a bending portion that extends outward in the vehicle width direction at both front portions along the vehicle front-rear direction and bends outward in the vehicle width direction from the vehicle front side toward the vehicle rear side. A pair of side rails, a first cross member connecting the pair of side rails on the vehicle front side of the bent portion, and a second cross connecting the pair of side rails on the vehicle rear side of the bent portion. A member, a cab mount bracket that protrudes outward from the bent portion in the vehicle width direction, and a rear portion of the vehicle and a vehicle inner portion in the vehicle width direction from a joint portion of the side rail and the first cross member or a vicinity of the joint portion. Extending to connect the joint portion or the vicinity of the joint portion and the vicinity of the center of the second cross member, or from the joint portion or the vicinity of the joint portion toward the vehicle rear side and the vehicle width direction outer side. And a connecting member that extends to connect the connecting portion or the vicinity of the connecting portion and an outer end of the cab mount bracket, and a fragile portion that is provided on the connecting member and is weak against a compressive load. ..

In the vehicle body frame structure of the first aspect, a compressive load acts on the connecting member during a frontal collision. Since the fragile portion is formed in the connecting member, the connecting member is deformed (bent) from the fragile portion as a starting point against the compressive load applied by the frontal collision. In this way, the deformation of the connecting member suppresses an increase in deceleration during a head-on collision. Further, at the time of a minute lap collision, a compressive load acts on the connecting member located on the collision side, and the connecting member is deformed starting from the fragile portion. On the other hand, since a tensile load acts on the connecting member located on the anti-collision side, the connecting member is unlikely to be deformed starting from the fragile portion, and deformation on the anti-collision side can be suppressed.

INDUSTRIAL APPLICABILITY The present invention can provide a vehicle body frame structure capable of suppressing an increase in deceleration during a head-on collision and suppressing deformation on the side opposite to the collision side during a minute lap collision.

It is a top view showing the important section of the vehicle to which the body frame structure concerning a 1st embodiment was applied. FIG. 2 is an enlarged plan view of a portion indicated by an arrow 2 in FIG. 1. 3A is an end view taken along line 3A-3A in FIG. (B) It is a 3B-3B line end view of FIG. FIG. 4 is a sectional view taken along line 4-4 of FIG. 2. It is a top view which shows the state which the vehicle body frame structure shown in FIG. 1 deform|transformed by the microlap collision. It is a top view showing the important section of the vehicle to which the body frame structure concerning a 2nd embodiment was applied. FIG. 7 is an enlarged plan view of a portion indicated by an arrow 7 in FIG. 6. It is an enlarged plan view corresponding to Drawing 7 showing a modification of a 2nd embodiment. (A) It is a 9A-9A line end view of FIG. (B) It is a 9B-9B line end view of FIG. FIG. 10 is a sectional view taken along line 10-10 of FIG. 8. It is a top view which shows the state which the vehicle body frame|skeleton structure shown in FIG.

Hereinafter, a vehicle body frame structure according to an embodiment of the present invention will be described.
In addition, the arrow FR shown appropriately in the drawings indicates the front of the vehicle, the arrow UP indicates the upper side of the vehicle, and the arrow LH indicates the left side in the vehicle width direction. Further, in the following description, when front-rear, up-down, and left-right directions are used without special mention, they indicate front-rear in the vehicle front-rear direction, up-down in the vehicle up-down direction, and left-right in the vehicle left-right direction (vehicle width direction).

(First embodiment)
FIG. 1 shows a vehicle front portion 12 of a vehicle 10 to which a vehicle body frame structure S1 according to this embodiment is applied. As shown in FIG. 1, a pair of left and right side rails 14 are provided on both sides of the vehicle 10 in the vehicle width direction.

The side rails 14 extend along the vehicle front-rear direction outside the vehicle front portion 12 in the vehicle width direction, and a front tire (not shown) is disposed on the vehicle width direction outer side on the front portion 14A side of the side rails 14. To be done. Therefore, on the front portion 14A side of the side rail 14, in consideration of the interference with the front tire, the dimension of the side rail 14 in the vehicle width direction is set to be shorter than that of the vehicle front-rear direction central portion 14B side. There is.

Here, a bent portion 18 that bends outward in the vehicle width direction from the vehicle front side of the side rail 14 to the vehicle rear side is provided between the front portion 14A of the side rail 14 in the vehicle front-rear direction and the central portion 14B. There is. The bent portion 18 is provided on the vehicle rear side of the front tire, and the bent portion 18 connects the front portion 14A of the side rail 14 and the central portion 14B. The front portion 14A of the side rail 14 is disposed above the vehicle with respect to the central portion 14B in consideration of the arrangement of the suspension unit and the like. Therefore, the bent portion 18 inclines downward from the front portion 14A of the side rail 14 toward the vehicle rear side.

A bumper reinforcement 20 spans the front ends of the pair of side rails 14 along the vehicle width direction. An energy absorbing member such as a crash box may be arranged between the front end of the side rail 14 and the bumper reinforcement 20. In addition, in the present embodiment, the bumper reinforcement 20 is longer than the front portion 14A of the side rail 14 and shorter than the central portion 14B. It may be formed long.

On the vehicle rear side of the bumper reinforcement 20, a plurality of cross members 22, 24, 26, 28 are bridged between the pair of side rails 14 along the vehicle width direction. As a result, a ladder-shaped frame is formed in the vehicle front portion 12 of this embodiment. The cross members 22 and 24 are provided on the front portion 14A side of the side rail 14, and the cross members 26 and 28 are provided on the central portion 14B side of the side rail 14. Further, in FIG. 1, the front portion 14A and a part of the central portion 14B of the side rail 14 are illustrated, but a plurality of cross members are also bridged between the pair of side rails 14 on the rear side thereof. There is.

As shown in FIG. 2, the cross member 24 connects the pair of side rails 14 on the vehicle front side of the bent portion 18. The cross member 24 is an example of the first cross member in the present invention.

The cross member 26 connects the pair of side rails 14 on the vehicle rear side of the bent portion 18. The cross member 26 is an example of the second cross member of the present invention.

Between the cross member 22 and the cross member 24 in the front portion 14A of the side rail 14, a metal engine mount bracket 30 projecting inward in the vehicle width direction of the side rail 14 is arranged. An engine mount (not shown) is attached to the engine mount bracket 30, and the engine unit can be connected to the side rail 14 via the engine mount and the engine mount bracket 30.

Further, between the cross member 22 and the cross member 24 in the front portion 14A of the side rail 14, a suspension mount made of metal which is slightly forward of the engine mount bracket 30 and protrudes outward in the vehicle width direction of the side rail 14. A bracket 32 is provided. A suspension mount (not shown) is attached to the suspension mount bracket 32, and the suspension unit can be connected to the side rail 14 via the suspension mount and the suspension mount bracket 32.

Further, a cab mount bracket 34 that projects outward from the bent portion 18 in the vehicle width direction is provided on the bent portion 18 that is behind the suspension mount bracket 32 in the vehicle. Further, when viewed from the vehicle front side, the cab mount bracket 34 is in a state of protruding most outward in the vehicle width direction.

The cab mount bracket 34 is gradually thinned from the inner side to the outer side in the vehicle width direction, and the cab mount bracket 34 is formed with a mounting hole 34A for mounting a cab mount (not shown). The cab (body) (not shown) can be connected to the side rail 14 via the cab mount and the cab mount bracket 34.

As shown in FIG. 2, the vicinity of the connecting portion 36 of the side rail 14 and the cross member 24 and the vicinity of the center of the cross member 26 are connected by a connecting member 38. Specifically, the vicinity of the joint portion 36 (in this embodiment, the end portion side of the cross member 24 in the vehicle width direction (the joint portion 36 side)) and the vicinity of the center of the cross member 26 are joined by the connecting member 38. There is. The present invention is not limited to the above configuration, and the connecting member 38 may connect the connecting portion 36 and the vicinity of the center of the cross member 26. The connecting member 38 extends from the vicinity of the coupling portion 36 toward the vehicle rear side (cross member 26 side) and inward in the vehicle width direction. As shown in FIG. 3B, the connecting member 38 has a U-shaped cross section, and the open portion faces the vehicle upper side. Further, one end portion 38A and the other end portion 38B of the connecting member 38 are fastened to the cross members 24 and 26 using bolts 40 and nuts 42, respectively. In FIG. 4, a fastening portion between the other end portion 38B of the connecting member 38 and the cross member 26 is shown.

In addition, the connecting member 38 is provided with a fragile portion 39 that is vulnerable to a compressive load. The configuration of the fragile portion 39 is not particularly limited as long as it is vulnerable to a compressive load as compared with the general portion 38C having a U-shaped cross section of the connecting member 38. In the present embodiment, as shown in FIG. 3A, the fragile portion 39 has a flat plate shape with no folded portions on both sides of the general portion 38C. Such a fragile portion 39 can be formed, for example, by cutting off the folded-back portions on both sides in a part of the connecting member 38.

Next, the operation and effect of the vehicle body frame structure S1 according to the present embodiment will be described.
In the vehicle body skeletal structure S1, when a compressive load is applied to the connecting member 38 during a frontal collision, the connecting member 38 is deformed (bends) starting from the fragile portion 39. In this way, the deformation of the connecting member 38 suppresses an increase in deceleration during a head-on collision.

Further, in the vehicle body frame structure S1, when a compressive load acts on the connecting member 38 located on the collision side during a minute lap collision, the connecting member 38 is deformed (bends) from the fragile portion 39 as a starting point. On the other hand, since a tensile load acts on the connecting member 38 located on the anti-collision side, the connecting member 38 is unlikely to be deformed starting from the fragile portion 39, and deformation on the anti-collision side can be suppressed. That is, the anti-collision side is supported by the connecting member 38 located on the anti-collision side, and deformation of the anti-collision side is suppressed (see FIG. 5 ).

From the above, according to the vehicle body skeleton structure S1, it is possible to suppress an increase in deceleration at the time of a head-on collision, and it is possible to suppress deformation of the side opposite to the collision side at the time of a minute lap collision.

Further, in the vehicle body skeleton structure S1, since the connecting member 38 is arranged inside the side rail 14 in the vehicle width direction, by arranging the connecting member 38, it is possible to suppress a reduction in the degree of freedom in layout of the members forming the vehicle body skeleton. it can.

(Second embodiment)
Next, a vehicle body skeleton structure S2 according to the second embodiment of the present invention will be described. The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. Further, in the present embodiment, the arrangement position of the connecting member 44 is different from that of the first embodiment, and therefore only the arrangement position of the connecting member 44 and the configuration related thereto will be described below.

As shown in FIGS. 6 and 7, the connecting portion 36 of the side rail 14 and the cross member 24 and the outer end (tip in the protruding direction) of the cab mount bracket 34 are connected by a connecting member 44. In addition, in the present invention, the vicinity of the joint portion 36 (for example, a portion deviated in the vehicle front-rear direction with respect to the joint portion 36) and the outer end of the cab mount bracket 34 may be joined to each other by the joint member 38 in the above configuration. The connecting member 44 extends from the coupling portion 36 toward the vehicle rear side (cross member 26 side) and outward in the vehicle width direction. As shown in FIG. 9B, the connecting member 44 has a U-shaped cross section, and the open portion faces the front side of the vehicle. Further, one end 44A and the other end 44B of the connecting member 44 are fastened to the side rail 14 and the cab mount bracket 34 using bolts 40 and nuts 42, respectively. In FIG. 10, a fastening portion between the one end portion 44A of the connecting member 44 and the side rail 14 is shown.

Further, the connecting member 44 is provided with a fragile portion 46 that is vulnerable to a compression load. The fragile portion 46 is not particularly limited in its configuration as long as it is vulnerable to a compressive load as compared with the general portion 44C having a U-shaped cross section of the connecting member 44. In this embodiment, as shown in FIG. 9(A), the fragile portion 46 has a flat plate shape with no folded portions on both sides of the general portion 44C. Such a fragile portion 46 can be formed by cutting off the folded-back portions on both sides in a part of the connecting member 44, for example.

Note that the present invention is not limited to the above configuration, and may be configured to be coupled to the coupling portion 36 and the cab mount bracket 34 via the brackets 50 and 52 like the coupling member 48 shown in FIG. The connecting member 48 has a U-shaped cross section, the open portion faces the vehicle rear side, and the fragile portion 39 similar to that in the first embodiment is provided.

Next, the operation and effects of the vehicle body frame structure S2 according to this embodiment will be described.
In the vehicle body skeleton structure S2, when a compressive load is applied to the connecting member 44 during a frontal collision, the connecting member 44 is deformed (bends) starting from the fragile portion 46. In this way, the deformation of the connecting member 44 suppresses an increase in deceleration during a head-on collision.

Further, in the vehicle body frame structure S2, when a compressive load acts on the connecting member 44 located on the collision side during a minute lap collision, the connecting member 44 deforms (bends) from the fragile portion 46 as a starting point. On the other hand, since a tensile load acts on the connecting member 44 located on the anti-collision side, the connecting member 44 is unlikely to be deformed starting from the weakened portion 46, and deformation on the anti-collision side can be suppressed. That is, the anti-collision side is supported by the connecting member 44 located on the anti-collision side, and deformation of the anti-collision side is suppressed (see FIG. 11 ).

From the above, according to the vehicle body skeleton structure S2, it is possible to suppress an increase in deceleration at the time of a head-on collision, and it is possible to suppress deformation on the side opposite to the collision side at the time of a minute lap collision.

Further, in the vehicle body skeleton structure S2, the connecting member 44 is arranged outside the side rail 14 in the vehicle width direction, so that the connecting member 44 is arranged inside the side rail 14 in the vehicle width direction (between the pair of side rails 14), for example. As compared with the configuration described above, the deformation on the anti-collision side can be further suppressed.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above, and various modifications other than the above can be carried out without departing from the gist of the invention. Of course.

S1, S2 Body frame structure 12 Vehicle front part 14 Side rail 18 Bending part 24 Cross member (first cross member)
26 Cross Member (2nd Cross Member)
34 cab mount bracket 36 connecting part 38 connecting member 39 weak part 44 connecting member 46 weak part 48 connecting member

Claims (1)

A pair of side rails that extend along the vehicle front-rear direction on the vehicle width direction outer side of the vehicle front portion and that include a bent portion that bends toward the vehicle width direction outer side from the vehicle front side toward the vehicle rear side,
A first cross member connecting the pair of side rails on the vehicle front side of the bent portion;
A second cross member connecting the pair of side rails on the vehicle rear side of the bent portion;
A cab mount bracket projecting outward from the bent portion in the vehicle width direction,
The connecting portion between the side rail and the first cross member or the vicinity of the connecting portion extends toward the vehicle rear side and the vehicle width direction inner side from the connecting portion or the vicinity of the connecting portion and the second cross member. Of the cab mount bracket, or connecting to the vicinity of the center of the cab mount bracket, or extending from the coupling portion or the vicinity of the coupling portion toward the vehicle rear and outward in the vehicle width direction. A connecting member for connecting the outer end,
A fragile portion provided on the connecting member and vulnerable to a compressive load,
Car body skeletal structure having.