JPS5941905Y2 - Automotive floor frame members - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a floor frame member of an automobile.

Generally, a floor frame member in the front-rear direction is attached to the lower surface of the floor panel of an automobile in order to ensure rigidity.

For example, in a tilt cabin vehicle, as shown in FIGS. 1 and 2, a floor frame member 2° with a U-shaped cross section extending in the longitudinal direction of the vehicle body is provided on the lower surface of the cabin floor 1 in which the engine service hole 1a is bored. 2 are provided symmetrically, and front cab mount members 3, 3 at the front of the cabin 5 and rear cab mount members 4, 4 at the rear of the cabin 5 are connected by these floor frame members 2, 2.

However, the above front cab mount member 3
, 3 are different from the intervals between the cab mount members 4, 4, and the floor panel 1 has undulations, so the floor frame member 2 is curved both in the vehicle width direction and in the vertical direction. This resulted in a complicated shape, which made it extremely difficult to carve the floor frame member 2.

This invention forms the above-mentioned floor frame member by connecting two members, a first frame member extending substantially linearly when viewed from above the vehicle body in the longitudinal direction of the vehicle body, and a curved second frame member. In addition, the joining end portion of the first frame member is curved and formed symmetrically with respect to the longitudinal center line along the curved shape of the second frame member, and the first frame member and the second frame member are bonded together. By adopting a structure in which the overlapping area with the connecting portion gradually decreases, stress concentration at the connecting portion is alleviated.

A first embodiment of this invention will be described below with reference to FIGS. 3 and 4.

The first frame member 6 has the shape of the linearly extending front portion A of the floor frame member 2 shown in FIGS. The first part B and the rear part C each have a continuous shape.
The floor frame member 8 is formed by connecting the rear end of the frame member 6 and the front end of the second frame member 1.

To explain the above-mentioned joint, the first frame member 6 having a U-shaped cross section is formed to have a slightly narrower width than the second frame member 7 which also has a U-shaped cross section, and the rear end of the first frame member 6 are drawn symmetrically with respect to the longitudinal center line, and the side edges 6 have a U-shaped cross section on the center side of the vehicle body.
The outer surface of a is the cross section U of the second frame member 7 on the vehicle body center side.
The first frame member 6 is curved to follow the inner surface of the side edge 7a, and the rear end of the first frame member 6 is overlapped with the inner surface of the front end of the second frame member 7 and connected by welding.

Note that 6b and 7b are the sides of the first frame member 6 and the second frame member T closer to the outside of the vehicle body, and 6ct6d, 7c, and 7d are the above-mentioned sides 5a and 5b.

These are flanges formed at the upper ends of each of 7a and 7b and fixed to the lower surface of the cabin floor 1.

In the above structure, the floor frame member 8 is formed by joining two members, the first frame member 6 and the second frame member γ, so that the entire length of the second frame member, which has a complicated curved shape, is longer than that of the conventional floor frame member. The first frame member is shorter than the second frame member, and the shape of each frame member is simpler, making it easier to process.
The total weight of the floor frame member 8 can be reduced by increasing the thickness of the frame member 6 and decreasing the thickness of the second frame member 7, which receives a small load.

In addition, since the rear end portions of the first frame members 6 are drawn symmetrically, the left and right first frame members 6 have the same shape, making it possible to share parts.
The overlapping area of the connection portion between the frame member 6 and the second frame member 7 gradually decreases toward the rear, and stress concentration at the connection portion is alleviated.

Note that in the first embodiment, the first frame member 6 is thick and the second frame member 7 is thin, but if both frame members have the same thickness, the fifth As shown in the figure or FIG. 6, the overlapping area of the connecting portion may be formed so as to gradually decrease toward the front.

In the second embodiment shown in FIG. 5, side sides 7a and 7b of the second frame member T having a U-shaped cross section are extended forward to form a triangular portion γ.
e and γf, and the cross-sectional area of the connecting portion with the first frame member 6 is gradually decreased toward the front, so that stress concentration at the front end of the connecting portion is alleviated.

Note that the first frame member 6 is formed in the same shape as the first embodiment.

The third embodiment shown in FIG.
In this embodiment, the stress concentration at the front end of the connecting portion is alleviated in the same way as in the second embodiment.

In the first to third embodiments described above, the first frame member has the shape of the rear part C of the conventional floor frame member 2,
Further, the second frame member can be formed in a continuous shape of the front portion A and the middle portion B of the conventional floor frame member 2, respectively.

Alternatively, a floor frame member may be formed by connecting three members: a first frame member shaped like the front part A, a second frame member shaped like the middle part B, and a third frame member shaped like the rear part C. In this case, even if the distance between the left and right side cab mount members 4, 4 changes when installing cabins with different widths on the same chassis, it is only necessary to change the curved second frame member, and the straight There is no need to change the shapes of the first frame member and the third frame member, and parts can be shared.

Note that each of the above embodiments has a structure in which the first frame member 6 is overlapped inside the second frame member 7,
The ends of the first frame member 6 are drawn symmetrically, but the first frame member 6 is formed on the outside of the second frame member 7.
In the case of a structure in which the frame members 6 are overlapped, the first frame member 6 may have a structure in which the end portions are symmetrically curved into a shape that gradually expands toward the end portions.

As explained above, this invention is a floor frame member that is arranged symmetrically on the lower surface of the floor panel of the vehicle body and has a U-shaped cross section that curves in the vehicle width direction.
The above-mentioned floor frame member is formed by overlappingly connecting a first frame member extending in a substantially straight line in the longitudinal direction of the vehicle body and a curved second frame member at their ends, and Both sides of the U-shaped cross section of the connection end of the first frame member that overlaps with the curved end of the second frame member are curved along the curved shape of the second frame member symmetrically with respect to the longitudinal center line. Since the overlapping area of both frame members is gradually reduced, workability is improved, parts can be shared, and stress concentration associated with overlapping connections is reduced.

[Brief explanation of the drawing]

Figure 1 is a plan view of the cabin floor of a tilt cabin vehicle.
Figure 2 is a side view of Figure 1, Figure 3 is a plan view of the main parts of the first embodiment of this invention, Figure 4 is a perspective view of Figure 3, and Figure 5 is a perspective view of the second embodiment. FIG. 6 is a perspective view of the third embodiment. 1: cabin floor (floor panel), 2, 8: floor frame member, 6: first frame member, 7: second frame member.

Claims (1)

[Scope of utility model registration request] The floor frame member is arranged symmetrically on the lower surface of the floor panel of the vehicle body and has a U-shaped cross section that curves in the vehicle width direction. It is formed by overlappingly connecting a first frame member extending in a shape and a second frame member having a curved shape at their ends, and
Both sides of the U-shaped cross section of the connection end of the first frame member that overlaps with the curved end of the frame member extend left and right along the curved shape of the second frame member with respect to the longitudinal center line of the first frame member. An automobile floor frame member characterized by being symmetrically curved.