Vehicle floor support structure

Abstract

Provided is a vehicle floor support structure in which a bellows-like floor panel 3, in which recessed sections and projecting sections extending in the longitudinal direction of a vehicle are alternately formed in the vehicle width direction, is supported by a floor cross member 21 extending in the vehicle width direction. A floor reinforcing plate 50 having a bead extending in the vehicle width direction along the longitudinal direction of the floor cross member 21 is provided between the floor cross member 21 and the floor panel 3. The floor cross member 21 and the floor panel 3 are fixed to each other with the floor reinforcing plate 50 therebetween.

Description

Vehicle floor support structure

[0001] The present invention relates to a floor support structure for a vehicle.

[0002] Many vehicles with a cargo bed or cargo box, such as pickup trucks, are equipped with a pair of side members spaced apart in the vehicle width direction and extending in the fore-and-aft direction of the vehicle, and a cross member extending in the vehicle width direction and connecting the pair of side members, as in Patent Document 1, for example. The floor of the cargo bed or the like is placed on a part of the cross member or side member and fixed with bolts or the like. In addition, the floor is often formed by bending a thin plate in a bellows-like cross section.

[0003] JP 2016-30573 A

[0004] In the vehicle described in Patent Document 1, the cross section of the floor (floor panel) in the vehicle width direction is formed in an accordion shape. Therefore, even if the floor strength can be ensured against deformation in the front-rear direction of the vehicle, it may not be strong enough to withstand deformation in the left-right direction of the vehicle.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a floor support structure for a vehicle that improves the strength of the floor support portion.

[0006] In order to achieve the above-mentioned object, the vehicle floor support structure of the present invention is characterized by comprising a bellows-shaped floor panel having concave and convex portions extending in the fore-and-aft direction of the vehicle and alternately formed in the vehicle width direction, a floor cross member extending in the vehicle width direction along the underside of the floor panel to support the floor panel, and a first reinforcing member having a bead extending in the vehicle width direction along the longitudinal direction of the floor cross member and interposed between the floor cross member and the floor panel.

[0007] This allows the floor cross member and the first reinforcing member having the bead to improve the strength of the floor panel against deformation in the vehicle width direction.

[0008] Preferably, the floor cross member has a downwardly convex hat-shaped longitudinal cross section in the vehicle longitudinal direction with flanges at the front and rear, the first reinforcing member is formed so that the bead protrudes downward and has plate surface portions extending along the bead at the front and rear of the bead, the bead is positioned within the concave cross section of the floor cross member, and the plate surface portions are joined in a state where they are sandwiched between the floor panel and the flange portions of the floor cross member. This allows the bead to be positioned so that it is stored within the floor cross member, making the structure of the floor support section compact and allowing the first reinforcing member to be firmly fixed between the floor cross member and the floor panel.

[0009] Preferably, the plate surface portion of the first reinforcing member is curved to match the bellows shape of the floor panel and is joined to the top surface of the convex portion of the floor panel and to the bottom surface of the concave portion together with the flange portion of the floor cross member. This allows the first reinforcing member to be installed on the underside of the bellows-shaped floor panel, effectively improving the strength of the floor panel.

[0010] Preferably, the first reinforcing member has a higher rigidity than the floor panel but a lower rigidity than the floor cross member, thereby suppressing the difference in rigidity at the fixed portion between the floor panel and the floor cross member and reducing stress concentration.

[0011] Preferably, the floor panel is a floor panel for a vehicle whose body is supported on a chassis frame, the floor cross member is fixed to a side member of the chassis frame extending in the vehicle longitudinal direction, and the first reinforcing member is arranged to overlap a fixing position between the floor cross member and the side member in a top view. This brings the fixing position between the floor cross member and the side member closer to the fixing position between the floor panel and the floor cross member, thereby reducing the load acting near the floor support portion.

[0012] Preferably, the floor cross member has a second reinforcing member that reinforces the fixed position between the floor cross member and the side member, and the first member is arranged to overlap the second member in a top view, thereby enabling the second reinforcing member to further improve the strength of the vehicle structure in the vicinity of the floor support portion.

[0013] Preferably, the floor cross member is disposed near a support position of the side member for a suspension device of the vehicle, thereby reducing the distance between the support position of the suspension device and the floor support portion and improving the strength of the vehicle structure near the floor support portion, including the side member.

[0014] According to the present invention, the floor cross member and the first reinforcing member can improve the strength of the floor panel against deformation in the vehicle width direction.

[0015] FIG. 1 is a top view of the rear part of a vehicle that employs a floor support structure according to an embodiment of the present invention. FIG. 2 is a perspective view of the vicinity of a floor support part in the rear left part of the vehicle according to this embodiment, viewed from the lower left. FIG. 3 is a perspective view of the floor support part as viewed from above. FIG. 4 is a perspective view of the floor support part as viewed from the lower rear. FIG. 5 is a perspective view showing the structure of a floor cross member and a floor reinforcing plate in the floor support part. FIG. 6 is a perspective view showing the structure of a floor cross member and a cross member reinforcing plate in the floor support part. FIG. 7 is a longitudinal cross-sectional view of the floor support part in the vehicle fore-and-aft direction. FIG. 8 is a longitudinal cross-sectional view of the floor support part in the vehicle width direction.

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a top view of the rear of a vehicle 1 employing a floor support structure according to an embodiment of the present invention. Fig. 2 is a perspective view of the vicinity of a floor support portion in the rear left portion of the vehicle 1 according to this embodiment, viewed from the lower left. Note that in Fig. 2, tires and side bodies are not shown.

[0017] The vehicle floor support structure of the present invention is employed in a vehicle such as a pickup truck in which the bed or cargo box (body) is supported on a chassis frame such as side members 7, 8.

[0018] 1 and 2, a luggage box 2 is provided at the rear of a vehicle 1 according to this embodiment. The luggage box 2 has a floor panel 3, side gates 4 and 5 provided at the left and right ends in the vehicle width direction, respectively, and a tailgate 6 provided at the rear end of the vehicle.

[0019] The vehicle 1 is provided with a pair of side members 7, 8 that extend in the vehicle longitudinal direction and are spaced apart in the vehicle width direction. The vehicle 1 is also provided with a plurality of cross members 10 that extend in the vehicle width direction and connect the pair of side members 7, 8.

[0020] An axle 15 of the rear wheels of the vehicle 1 is suspended by a suspension device 17 using leaf springs 16. One of the multiple cross members 10 is disposed adjacent to the front side of a rear support portion 18 of the leaf spring 16.

[0021] A plurality of floor cross members 20, 21 extending in the vehicle width direction are provided on the underside of the floor panel 3 of the luggage box 2. Of the plurality of floor cross members, the rear end floor cross member 20 located at the rear end of the vehicle is located at the rear end of the floor, and the second floor cross member 21 from the rear is located adjacent to the front side of the rear support portion 18 of the leaf spring 16, i.e., above the cross member 10.

[0022] The floor cross member 21 extends in the vehicle width direction up to near the vehicle width end of the cargo box 2, and is connected to the lower ends of L-shaped side gate members 22, 23 arranged along the left and right side gates 4, 5 of the cargo box 2 near the vehicle width end.

[0023] The floor panel 3 of the cargo box 2 is divided in the vehicle width direction near the side members 7 and 8. That is, the floor panel 3 is configured as three separate parts: a center floor panel 25 located between the left and right side members 7 and 8, a right floor panel 26 located on the right side in the vehicle width direction near the right side member 8, and a left floor panel 27 located on the left side in the vehicle width direction near the left side member 7.

[0024] FIG. 3 is a perspective view of the connection between the floor cross member 21 and the floor panel 3 near the left side member 7 (hereinafter referred to as the floor support portion) from above. FIG. 4 is a perspective view of the floor support portion from below and rearward. FIG. 5 is a perspective view of the floor cross member 21 and floor reinforcement plate 50 at the floor support portion from above. FIG. 6 is a perspective view of the floor cross member 21 and floor cross member reinforcement plate 45 at the floor support portion. Note that FIG. 6 also shows the side gate member 22. FIG. 7 is a longitudinal cross-section of the floor support portion in the vehicle's fore-aft direction. FIG. 8 is a longitudinal cross-section of the floor cross support portion in the vehicle's width direction. Note that the black circles and black squares in FIGS. 3, 7, and 8 indicate spot weld locations, with the black circles indicating welds where two members are overlapped and the black squares indicating welds where three members are overlapped. Also, FIG. 7 is a cross-sectional view of the A-A portion shown in FIG. 3, and FIG. 8 is a cross-sectional view of the B-B portion.

[0025] As shown in Figures 1 and 3, the right end of the left floor panel 27 and the left end of the center floor panel 25 overlap, for example, by several centimeters, and are connected at this overlapping portion 30 by spot welding at multiple points aligned in the fore-and-aft direction of the vehicle.

[0026] As shown in Figures 3 and 4, the floor panels 3, i.e., the center floor panel 25, the right floor panel 26, and the left floor panel 27, are formed from thin steel plates, and their longitudinal cross sections in the vehicle width direction are uneven, for example, every few centimeters. In other words, when viewed from the underside, they have an accordion-like shape with concave and convex portions 3a and 3b extending in the fore-and-aft direction of the vehicle alternately formed in the vehicle width direction.

[0027] 3 to 5, the floor cross member 21 is made of steel plate, has a hat shape with an open top, and has a flange portion 21a at its upper end extending toward the front of the vehicle, and a flange portion 21b extending toward the rear of the vehicle. The floor panel 3 is placed on the upper surfaces of the flange portions 21a and 21b, and the flange portions 21a and 21b are spot-welded to the accordion-shaped bottom surface of the floor panel 3 to secure them to each other.

[0028] The left floor panel 27 and the center floor panel 25 overlap at their accordion-shaped undersides and are fixed by spot welding at the overlapping portion 30 (e.g., as shown by a in FIG. 3). In addition, where the overlapping portion 30 and the flange portions 21a and 21b overlap, three plates are overlapping and welded (e.g., as shown by d in FIG. 3).

[0029] The flanges 21a, 21b of the floor cross member 21 have widened portions 40 extending approximately several tens of centimeters (approximately the width of two bellows grooves) on both sides of the overlapping portion 30 between the center floor panel 25 and the left floor panel 27. At the widened portions 40 of the flanges 21a, 21b, the bottom surface of the floor panel 3 and the flanges 21a, 21b are fixed by spot welding at two locations aligned in the fore-aft direction of the vehicle (e.g., "b" in FIG. 3). At locations outside the widened portions 40 of the flanges 21a, 21b, the bottom surface of the floor panel 3 and the flanges 21a, 21b are fixed by spot welding at one location each (e.g., "c" in FIG. 3).

[0030] In addition, at the overlapping portion 31 between the right floor panel 26 and the center floor panel 25, the flange portions 21a, 21b of the floor cross member 21 are formed wide in the fore-and-aft direction of the vehicle and are fixed by spot welding at two points each in line in the fore-and-aft direction of the vehicle.

[0031] As shown in FIG. 2 , a bracket 41 is provided on the outer surface (left side surface) of the left side member 7 , and the floor cross member 21 and the bracket 41 are detachably fixed together by a bolt 42 .

[0032] As shown in Figure 6, a cross-member reinforcing plate 45 (second reinforcing member) is fixed by welding to the interior of the floor cross member 21, specifically to the inside of the hat-shaped wall surface. The cross-member reinforcing plate 45 is formed by bending a rectangular plate member into a U-shape along the inner wall surfaces of the bottom plate portion 21c and side plate portion 21d of the floor cross member 21. The cross-member reinforcing plate 45 has a hole that passes through together with the bottom plate portion 21c of the floor cross member 21, and is fixed by welding a nut 46. A bolt 42 that fixes the floor cross member 21 and the bracket 41 is fastened to this nut 46. In other words, the fixed portion of the floor cross member 21 to the left side member 7 is reinforced by the cross-member reinforcing plate 45.

[0033] Furthermore, as shown in FIGS. 3 to 8 , a rectangular floor reinforcing plate 50 (first reinforcing member) is provided on the underside of the floor panel 3. The floor reinforcing plate 50 extends in the vehicle longitudinal direction across the flange portions 21a and 21b. The floor reinforcing plate 50 is fixed by spot welding at its front and rear plate surface portions 52, respectively, while being sandwiched between the floor panel 3 or between the floor panel 3 and the floor cross member 21. In this embodiment, the floor reinforcing plate 50 and the floor panel 3 are fixed at six locations (welds f) at the front and rear of the floor cross member 21. Of these welds f, four locations in the vehicle width center secure the three components together: the floor panel 3, the floor reinforcing plate 50, and the flange portions 21a or 21b. The plate surface portion 52 of the floor reinforcement plate 50 is curved to match the accordion shape of the floor panel 3, and is joined to the top surface of the convex portion 3b of the floor panel 3, and is joined to the bottom surface of the concave portion 3a of the floor panel 3 together with the flange portions 21a, 21b of the floor cross member 21.

[0034] The floor reinforcement plate 50 is arranged so as to overlap, in a top view, with the bolts 42 and nuts 46 that are the fixing parts between the floor cross member 21 and the bracket 41. Therefore, the floor reinforcement plate 50 and the cross member reinforcement plate 45 are arranged so as to overlap at least partially, in a top view.

[0035] The floor reinforcement plate 50 also has a bead portion 51 (bead) that is bent downward and protrudes from the center portion in the vehicle's longitudinal direction. The bead portion 51 is provided so as to fit into a recess 21e in the center portion in the vehicle's longitudinal direction of the floor cross member 21. The bead portion 51 preferably extends substantially the full width of the floor reinforcement plate 50 in the lateral direction and is provided so as to contact the inner wall surface of the floor cross member 21. Furthermore, plate surface portions 52 extend along the bead portion 51 in front of and behind the bead portion 51 of the floor reinforcement plate 50.

[0036] The rigidity of the floor reinforcement plate 50 is set to be lower than that of the floor cross member 21 and higher than that of the floor panel 3 (left floor panel 27). Note that the structure of the right portion of the floor cross member 21 near the connection between the floor cross member 21 and the side member 8 is also configured symmetrically to the structure of the left portion of the floor cross member 21 described above.

[0037] As described above, in this embodiment, the cargo box 2 of the vehicle 1 is provided with the floor cross member 21 that extends in the vehicle width direction and supports the floor panel 3 from below. The floor cross member 21 extends to the vicinity of the vehicle width end of the cargo box 2 and is placed on the upper surfaces of a pair of left and right side members 7, 8 of the vehicle 1, and brackets 41 provided on the side members 7, 8 and the floor cross member 21 are fixed with bolts 42.

[0038] The floor panel 3 has an accordion-like shape with concave and convex portions extending in the vehicle's fore-and-aft direction alternately formed in the vehicle's width direction, and the floor panel 3 itself has high strength against deformation in the vehicle's fore-and-aft direction, but low strength against deformation in the vehicle's width direction. In contrast, this embodiment includes a floor cross member 21 and a floor reinforcing plate 50 that is interposed between the floor cross member 21 and the floor panel 3 and extends in the vehicle's width direction. As a result, the floor cross member 21 and floor reinforcing plate 50 extending in the vehicle width direction can improve the strength of the floor panel 3 against deformation in the vehicle's width direction.

[0039] Furthermore, the floor reinforcement plate 50 is provided with a bead portion 51 that protrudes downward along the longitudinal direction of the floor cross member 21 and extends in the vehicle width direction, thereby further improving the strength of the floor panel 3 against deformation in the vehicle width direction.

[0040] The floor cross member 21 has a hat-shaped cross section in the vehicle longitudinal direction that is open at the top and has a recess 21e on the upper surface. The bead portion 51 of the floor reinforcing plate 50 is positioned to fit into the recess 21e of the floor cross member 21. This allows the bead portion 51 to be installed so that it is housed within the floor cross member 21, making it possible to compact the structure of the floor support section. In addition, the plate surface portion 52 of the floor reinforcing plate 50 is joined in a sandwiched state between the floor panel 3 and the flange portions 21a, 21b of the floor cross member 21, allowing the floor reinforcing plate 50 to be firmly fixed.

[0041] The plate surface portion 52 of the floor reinforcement plate 50 is curved to match the accordion-like shape of the floor panel 3, and is joined to the top surface of the convex portion 3b of the floor panel 3, and is joined to the bottom surface of the concave portion 3a of the floor panel 3 together with the flange portions 21a, 21b of the floor cross member 21. This allows the floor reinforcement plate 50 to be installed to match the shape of the underside of the accordion-like floor panel 3, effectively improving the strength of the floor panel 3.

[0042] Furthermore, the floor reinforcement plate 50 has higher rigidity than the floor panel 3 but lower rigidity than the floor cross member 21. In this way, the floor reinforcement plate 50 is interposed at the connection between the thin floor panel 3 and the floor cross member 21, which is a strength member, to reduce the difference in rigidity at each connection. Therefore, stress concentration at the connection between the floor panel 3 and the floor cross member 21 can be suppressed, and the strength of the floor support portion can be improved.

[0043] Additionally, the floor reinforcement plate 50 is positioned so that the bolts 42, which are the fixing positions between the floor cross member 21 and the side members 7 and 8, overlap in a top view. This reduces the distance between the fixing positions (bolts 42) between the side members 7 and 8 and the floor cross member 21 and the fixing positions between the floor panel 3 including the floor reinforcement plate 50 and the floor cross member 21, thereby reducing the load acting on the floor support portion.

[0044] The floor reinforcement plate 50 also extends in the fore-and-aft direction of the vehicle and is fixed to each of the flange portion 21a located on the front side of the floor cross member 21 and the flange portion 21b located on the rear side of the floor cross member 21. In other words, the floor reinforcement plate 50 is fixed to the floor cross member 21 at multiple points at positions spaced apart from each other in the fore-and-aft direction of the vehicle, so that the floor reinforcement plate 50 and the floor panel 3 can be firmly fixed together.

[0045] Additionally, the floor cross member 21 is provided with a cross member reinforcing plate 45 at the position where it is fixed to the side members 7, 8. This improves the strength of the fixing portion between the floor cross member 21 and the side members 7, 8, and further improves the strength of the vehicle structure near the floor support portion.

[0046] Furthermore, the cross member reinforcement plate 45 and the floor reinforcement plate 50 are arranged so that they partially overlap when viewed from above. This brings the fixing position between the floor cross member 21 and the side members 7, 8 closer to the fixing position between the floor cross member 21 and the floor panel 3, thereby reducing the load acting near the floor support portion.

[0047] The floor cross member 21 and the side members 7, 8 are arranged to be fixed to each other near the support positions of the side members 7, 8 for the rear ends of the leaf springs 16 that form the suspension devices 17 of the vehicle 1.

[0048] This brings the support portion 18 of the leaf spring 16 on the side members 7, 8 closer to the fixed positions between the side members 7, 8 and the floor cross member 21, and the fixed positions between the side members 7, 8 and the floor cross member 21, thereby shortening the distance between the support portion 18 of the leaf spring 16 and the floor support portion, and further reducing the load acting near the floor support portion including the side members 7, 8.

[0049] The present invention is not limited to the above embodiment. For example, in the above embodiment, the present invention is applied to one of the floor cross members 21 of the luggage box 2, which is located near the rear support portion 18 of the leaf spring 16 that supports the rear axle. However, the present invention may be applied to other floor cross members.

[0050] The present invention can be widely applied to vehicle floor support structures in which the floor is supported by a floor cross member.

[0051] REFERENCE SIGNS LIST 1 vehicle 3 floor panel 3a concave portion 3b convex portion 7, 8 side member 17 suspension device 18 support portion 21 floor cross member 21a flange portion 21b flange portion 21e recess 45 cross member reinforcing plate (second reinforcing member) 50 floor reinforcing plate (first reinforcing member) 51 bead portion (bead) 52 plate surface portion

Claims

1. a bellows-shaped floor panel in which concave portions and convex portions extending in the vehicle longitudinal direction are alternately formed in the vehicle width direction; a floor cross member that is convex downward and extends in the vehicle width direction along the lower surface of the floor panel to support the floor panel; a first reinforcing member having a bead extending in the vehicle width direction along the longitudinal direction of the floor cross member and interposed between the floor cross member and the floor panel; The bead is formed to protrude downward and is provided with a space between it and the bottom surface of the floor cross member. A vehicle floor support structure comprising:

2. The floor cross member has a hat-shaped longitudinal cross section in the vehicle front-rear direction with flange portions at the front and rear, the first reinforcing member has plate surface portions extending along the bead on both sides of the bead, The bead is arranged so as to be positioned within the concave cross section of the floor cross member, and the plate surface portion is joined in a state where it is sandwiched between the floor panel and the flange portion of the floor cross member.

2. The vehicle floor support structure according to claim 1.

3. The plate surface portion of the first reinforcing member is curved to match the bellows shape of the floor panel, and is joined to the top surface of the convex portion of the floor panel, and is joined to the bottom surface of the concave portion together with the flange portion of the floor cross member.

3. The vehicle floor support structure according to claim 2.

4. The first reinforcing member has a higher rigidity than the floor panel and a lower rigidity than the floor cross member.

4. The vehicle floor support structure according to claim 1, wherein the floor support structure is a support structure for a vehicle.

5. The floor panel is a floor panel of a vehicle whose body is supported on a chassis frame, The floor cross member is fixed to a side member of the chassis frame extending in the vehicle front-rear direction, The first reinforcing member is disposed so as to overlap a fixed position between the floor cross member and the side member in a top view.

2. The vehicle floor support structure according to claim 1.

6. a second reinforcing member provided on the floor cross member to reinforce the fixed position between the floor cross member and the side member; The first reinforcing member is disposed so as to overlap the second reinforcing member in a top view.

6. The vehicle floor support structure according to claim 5.

7. The floor cross member is disposed in the vicinity of a support position of a suspension device of the vehicle on the side member.

6. The vehicle floor support structure according to claim 5.