JP6819554B2 - Vehicle frame structure - Google Patents

Description

The present invention relates to a vehicle frame structure.

In a vehicle having a frame structure in which the body is mounted on a frame which is a skeleton member, a kick-up frame described in Patent Document 1 or the like may be used as a pair of left and right frame members extending in the front-rear direction of the vehicle. In the kick-up frame, in order to secure a space for the axle to pass under the frame while lowering the floor of the passenger compartment, the frame is curved (kick-up) upward from the front and rear at the passage point of the axle.

A cross member is attached to the curved portion of the kick-up frame, which has an upward slope along the rear of the vehicle. For example, a cross member is attached to an inclined portion (rear inclined portion) formed for passing the rear axle downward. The cross member extends in the vehicle width direction and is provided between the inclined portions of the pair of kick-up frames to connect the inclined portions.

The cross member has, for example, a closed cross-sectional structure having a rectangular side view, and the inside is hollow. Further, both ends of the cross member in the vehicle width direction are expanded in the front-rear and vertical directions of the vehicle (up, down, left and right in the side view) according to the dimensions of the kick-up frame. A welding allowance to be welded to the kick-up frame is formed at the end of the enlarged diameter portion.

Japanese Unexamined Patent Publication No. 2007-053500

By the way, the cross member is formed with a reference hole as a reference at the time of assembly, a gap due to a tolerance (play) when assembling the members, and the like. While the vehicle is traveling in a puddle or a shallow river, water (muddy water) invades the inside of the cross member through the above holes and gaps. If this water stays inside the cross member, there is a risk of corrosion (rust).

Therefore, it is conceivable to provide a drain hole at the lowest point of the internal space of the cross member. For example, when the cross member is welded to the inclined portion of the kick-up frame, as illustrated in FIG. 5, the lower diameter-expanded portion 104 of the cross member 100 whose diameter is expanded downward along the outer side in the vehicle width direction is relative to each other. The lowest point 106 in the internal space 102 of the cross member 100 is provided in front of the vehicle, which is in a relatively low position.

For example, it is conceivable to punch out the lowest point 106 by press working to form a drain hole 108. However, the provision of the drain hole 108 causes another problem that the rigidity around the hole is reduced. That is, when a load is input to the lower diameter expanding portion 104, a response deformation such that the drain hole 108 is distorted occurs. That is, the periphery of the drain hole 108 is deformed with respect to the load input, and it becomes difficult to maintain the rigidity of the cross member 100. Therefore, an object of the present invention is to provide a vehicle frame structure capable of both securing a drain hole in a cross member and suppressing a decrease in rigidity.

The present invention relates to a vehicle frame structure. The structure includes a kick-up frame and a cross member. A pair of kick-up frames are provided on the left and right so as to extend in the front-rear direction of the vehicle. The cross member extends in the width direction of the vehicle and connects the inclined portions of the pair of kick-up frames that have an upward slope along the rear of the vehicle. The cross member has a substantially rectangular closed cross-sectional structure in a side view, and diameter-expanded portions that are expanded in the front-rear and vertical directions of the vehicle are formed at both ends in the vehicle width direction along the outside in the vehicle width direction. A welding allowance to be welded to the inclined portion of the kick-up frame is formed at the end of the enlarged diameter portion in the vehicle width direction in the front-rear and up-down directions of the vehicle. Of the welding allowance, the lower diameter-expanded portion connected to the lower welding allowance along the inclined portion of the kick-up frame is in front of the vehicle, which is relatively low along the inclined portion, and is inside the enlarged diameter portion. A burring hole is formed at the lowest point in the space.

According to the above configuration, a burring hole is provided at a position that is the lowest point in the internal space of the enlarged diameter portion. By forming a hole at the lowest point, water retention in the cross member is eliminated. Further, since the burring hole is formed with a reinforcing flange around the hole, deformation of the hole shape at the time of load input is suppressed.

According to the present invention, it is possible to provide a vehicle frame structure capable of both securing a drain hole in the cross member and suppressing a decrease in rigidity.

It is a side view which illustrates the whole image of a kick-up frame. It is an enlarged perspective view which illustrates the vicinity of the inclined portion of the kick-up frame in the frame structure for a vehicle which concerns on this embodiment. FIG. 2 is a sectional view taken along the line AA of FIG. 2 is a cross-sectional view taken along the line BB of FIGS. 2 and 3. It is sectional drawing explaining the drain hole provided in the cross member which concerns on the prior art.

The vehicle frame structure according to the present embodiment will be described with reference to FIGS. 1 to 4. In the following, for convenience of illustration, only the right side or the left side of the vehicle may be shown, but due to the symmetry of the vehicle structure, the side not shown has the same structure.

Further, in FIGS. 1 to 4, the vehicle front-rear direction is indicated by the axis represented by the symbol FR, and the vehicle width direction (hereinafter, appropriately simply referred to as the width direction) is indicated by the axis represented by the symbol RW, and is the vertical direction. Is indicated by the axis represented by the symbol UP. The symbol FR is an abbreviation for Front, and the front-rear axis FR has the front of the vehicle in the positive direction. The symbol RW is an abbreviation for Right Right, and the width direction axis RW has the right width direction as the positive direction. Further, the height axis UP has an upward direction as a positive direction.

As shown in FIG. 1, these FR axes, RW axes, and UP axes are orthogonal to each other. Hereinafter, when the vehicle side structure according to the present embodiment is described, it will be appropriately described with reference to these three axes. For example, the "front end" refers to the end of any member on the positive direction of the FR axis, and the "rear end" refers to the end of any member on the negative direction of the FR axis. "Inside the width" refers to the inside of the vehicle in the width direction relative to the RW axis, and "outside the width" refers to the outside of the vehicle in the width direction relative to the RW axis. Further, "upper side" relatively refers to the positive direction side of the UP axis, and "lower side" relatively refers to the negative direction side of the UP axis.

The vehicle frame structure according to the present embodiment includes a kick-up frame 10 and a cross member 20.

FIG. 1 illustrates a side view of the kick-up frame 10. The kick-up frame 10 is a skeleton member extending in the front-rear direction of the vehicle. The kick-up frame 10 has a substantially rectangular closed cross-sectional structure when viewed from the front, as illustrated in the cross-sectional view of FIG. 4, for example. For example, the kick-up frame 10 is formed by joining divided bodies having a U-shaped cross section divided in the vehicle width direction. The chevron pattern (jagged pattern) in FIG. 4 represents the welded portion.

Further, since the axles of the front wheels 12 (not shown) and the axles of the rear wheels 14 (not shown) shown in FIG. 1 are passed under the frame, the passing positions of the front wheel axles and the rear wheel axles of the kickup frame 10 are the same. The frame is curved upward compared to the front and back. Among the curved portions, an inclined portion 16 having an upward slope toward the rear of the vehicle is provided around the passing position of the rear wheel axle.

As illustrated in FIG. 2, the inclined portions 16 and 16 of the pair of left and right kick-up frames 10 and 10 are connected by the cross member 20. The cross member 20 is a skeleton member extending in the vehicle width direction, and is provided between the inclined portions 16 and 16 of the pair of left and right kick-up frames 10 and 10.

The cross member 20 has a substantially rectangular closed cross-sectional structure in a side view as illustrated in FIG. For example, the cross member 20 is formed by joining divided bodies having a U-shaped cross section divided in the vertical direction of the vehicle.

With reference to FIGS. 2 and 3, diameter-expanded portions 22 and 22 are provided at both ends of the cross member 20 in the vehicle width direction. In the diameter-expanded portion 22, the wall plate members in the vehicle front-rear and vertical directions constituting the cross member 20 are expanded in the vehicle front-rear and vertical directions toward the outside in the vehicle width direction. For example, as the lower wall plate 24 of the cross member 20 advances outward in the vehicle width direction, the lower wall plate 24 expands downward in the vehicle to form the lower diameter enlarged portion 22B.

With reference to FIG. 3, among the diameter-expanded portions 22, the upper diameter-expanded portion 22A and the lower diameter-expanded portion 22B are formed along the shape of the inclined portion 16 of the kick-up frame 10 which is the joint destination thereof. That is, the upper diameter-expanded portion 22A and the lower diameter-expanded portion 22B have a relatively low position in the front of the vehicle and a relatively high position in the rear of the vehicle. Therefore, as will be described later, the water that has entered the cross member 20 flows through the lower diameter-expanded portion 22B and flows outward and forward in the vehicle width direction along the gradient.

A welding allowance 30 (yosetsushiro) to be welded to the inclined portion 16 of the kick-up frame 10 is formed at the end of the enlarged diameter portion 22 in the vehicle width direction. The welding allowance 30 is formed at each end of the diameter-expanded portion 22 that extends in the front-rear and vertical directions of the vehicle, and extends in the front-rear and vertical direction of the vehicle, similarly to the diameter-expanded portion 22.

For example, the front welding allowance 30A and the rear welding allowance 30B provided in the front-rear direction of the vehicle are welded to the inner side surface 10A in the width direction of the kick-up frame 10. Further, the upper welding allowance 30C provided in the upward direction of the vehicle is formed along the shape of the inclined portion 16. That is, it is formed so as to have an upward slope along the rear of the vehicle, and is welded from the inner side surface 10A in the width direction of the kickup frame 10 to the upper surface 10B as illustrated in FIG. Further, the lower welding allowance 30D provided in the downward direction of the vehicle is also formed so as to have an upward slope along the shape of the inclined portion 16, that is, along the rear of the vehicle. The lower welding allowance 30D is welded to the lower surface 10C of the kickup frame 10.

In this way, the end opening in the vehicle width direction of the enlarged diameter portion 22 of the cross member 20 having a closed cross-sectional structure is closed by the kick-up frame 10. As described above, water enters the internal space 32 of the closed diameter-expanded portion 22 through a reference hole, a gap, or the like provided in the cross member 20. In order to quickly discharge the water from the internal space 32 to the outside, a burring hole 34 is formed as a drain hole in the enlarged diameter portion 22 of the cross member 20.

The burring hole 34 is provided at the lowest point of the internal space 32. As described above, the lower diameter enlarged portion 22B extends downward toward the outside in the vehicle width direction. Further, since the lower diameter expanding portion 22B is formed along the inclined portion 16 of the kickup frame 10, the lower diameter portion 22B is relatively lower toward the front of the vehicle. Therefore, the front end of the lower diameter enlarged portion 22B and the outer end in the vehicle width direction are the lowest points. A burring hole 34 is formed as a drain hole at the lowest point.

The outer end of the lower diameter expansion portion 22B in the vehicle width direction is connected to the lower welding allowance 30D. In order to prevent water from staying in the welded portion, the lower diameter enlarged portion 22B may be formed so that the lowest point of the internal space 32 is lower than the lower welding allowance 30D.

As described above, the burring hole 34 according to the present embodiment is provided in the front and lower corners of the enlarged diameter portion 22 of the vehicle. Qualitatively, when a load is input to the substantially rectangular enlarged diameter portion 22, a relatively large load is input to the corner portion thereof. In the present embodiment, when the drainage hole is provided in such a high load input region, the hole is made into a burring hole 34 to suppress a decrease in rigidity. In other words, in the present embodiment, since the drain hole at the joint portion between the cross member 20 and the kick-up frame 10 becomes a high stress portion, the drain hole has a burring structure to prevent a decrease in strength and drainage property. Is secured.

The burring hole 34 refers to a hole formed by so-called burring processing, and a flange 36 is provided (erected) around the through hole. That is, the rigidity around the hole is strengthened by erecting the flange 36 on the edge of the hole.

For example, when a load is input around the burring hole 34, the stress of the flange 36 prevents the hole shape from being deformed. As a result, deformation around the burring hole 34 is suppressed, and it is possible to secure a drain hole in the cross member 20 and suppress a decrease in rigidity at the same time.

10 Kick-up frame, 10A inner side surface, 10B upper surface, 10C lower surface, 16 kick-up frame inclined part, 20 cross member, 22 cross member diameter expansion part, 22A upper diameter expansion part, 22B lower diameter expansion part, 30 welding allowance , 30D Lower welding allowance, 32 Internal space of enlarged diameter part, 34 burring hole, 36 burring hole flange.

Claims (1)

A pair of left and right kick-up frames extending in the front-rear direction of the vehicle,
A cross member that extends in the vehicle width direction and connects the inclined portions of the pair of kick-up frames that form an upward slope along the rear of the vehicle.
It is a frame structure for vehicles equipped with
The cross member has a substantially rectangular closed cross-sectional structure in a side view, and both ends in the vehicle width direction are formed with diameter-expanded portions that are expanded in the front-rear and vertical directions of the vehicle along the outside in the vehicle width direction.
A welding allowance to be welded to the inclined portion of the kick-up frame is formed at the end of the enlarged diameter portion in the vehicle width direction in the front-rear and vertical directions of the vehicle.
Of the welding allowance, the lower diameter-expanded portion connected to the lower welding allowance along the inclined portion of the kick-up frame is the front of the vehicle which is relatively low along the inclined portion and is described above. A burring hole is formed at the lowest point in the internal space of the enlarged diameter portion.
Vehicle frame structure.

Images