Structure for supporting cargo platform of vehicle

JPWO2025009166A5Pending Publication Date: 2026-03-04
View PDF 0 Cites 0 Cited by

Patent Information

Application Number
JP2025530944
Authority / Receiving Office
JP · JP
Patent Type
Applications
Filing Date
2025-04-25
Publication Date
2026-03-04

AI Technical Summary

Technical Problem

Conventional vehicle cargo bed support structures experience reduced durability due to inefficient load release and high stress concentrations at the chassis fixing parts, where the cross member is fixed to the chassis frame, leading to potential deformation and reduced product lifespan.

Method used

A vehicle loading platform support structure that divides the fixing member into a first and second portion, with the first portion fixed to the outer end of the cross member and the second portion fixed outside the first portion, allowing for efficient load release and stress reduction by facilitating deformation near the fixing positions, and further enhances durability by transmitting loads to more rigid side panels and wheelhouse areas.

Benefits of technology

The solution effectively improves the durability of the chassis fixing portion by efficiently releasing loads and reducing stress concentrations, thereby enhancing the structural integrity and longevity of the cargo bed support system.

✦ Generated by Eureka AI based on patent content.
Patent Text Reader

Abstract

A cargo-platform-supporting structure 20 includes a chassis frame 30, a cross member 40 fixed to both the chassis frame 30 and a bottom part 10a of a cargo platform 10, and side posts 60 (fixing members) respectively fixed to a vehicle-widthwise outer end part 401 of the cross member 40 and the bottom part 10a of the cargo platform 10. The cross member 40 and the chassis frame 30 are fixed to each other by a chassis-fixing part 100 provided to the vehicle-widthwise outer end part 401 of the cross member 40. The side posts 60 each include a first portion 70 fixed to the vehicle-widthwise outer end part 401 of the cross member 40, and a second portion 80 fixed to the first portion 70 farther outward in the vehicle width direction than the vehicle-widthwise outer end part 401.
Need to check novelty before this filing date? Find Prior Art

Description

Vehicle loading platform support structure

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

[0002] Conventionally, technologies for supporting a cargo bed in a vehicle with a cargo bed have been known. For example, Patent Document 1 (Patent Document 1) describes a floor structure in which a floor panel for the cargo bed is laid on a floor frame including a pair of left and right chassis frames, a pair of left and right side members, and multiple cross members. In this floor structure, cross members spanning the side members are placed on the chassis frame to form a cargo bed floor that supports the cargo bed. Outriggers are fastened to the sides of the chassis frame as fixing parts, and each cross member is fixed to the chassis frame by fastening the outriggers to mount brackets fastened to each cross member and protruding in the fore-and-aft direction of the vehicle.

[0003] Japanese Patent Application Publication No. 11-268668

[0004] In the structure described in Patent Document 1, the outer end of the cross member in the vehicle width direction is fixed to the side member, which is a main component of the body frame and has relatively high rigidity. As a result, the load input from the chassis frame to the cross member cannot be efficiently released via the side member, which increases stress near the fixed part between the chassis frame and the cross member, and there is a risk that durability near the fixed part will decrease.

[0005] The present invention was made in consideration of these problems, and its purpose is to provide a vehicle cargo bed support structure that can improve durability in the vicinity of the chassis fixing portion, which is the fixing portion between the chassis frame that supports the cargo bed and the cross member.

[0006] In order to achieve the above-mentioned object, the vehicle cargo bed support structure of the present invention comprises a chassis frame located below the vehicle cargo bed, a cross member extending in the vehicle width direction along the bottom of the cargo bed and fixed to the chassis frame and the bottom of the cargo bed, respectively, and fixing members extending in the vehicle width direction along the bottom of the cargo bed and fixed to the vehicle width outer end of the cross member and the bottom of the cargo bed, respectively, wherein the cross member and the chassis frame are fixed to each other by a chassis fixing portion provided at the vehicle width outer end of the cross member, and the fixing member includes a first portion fixed to the vehicle width outer end of the cross member and a second portion fixed to the first portion further outward in the vehicle width direction than the fixing portion between the cross member and the first portion.

[0007] With this configuration, because the fixing member is divided into the first and second portions, the fixing member is more likely to deform near the fixed position between the first and second portions. As a result, the load input from the chassis frame to the cross member and transmitted to the first portion can be efficiently released by deformation of the fixing member, reducing stress generated near the chassis fixed portion. Therefore, the vehicle cargo bed support structure of the present invention makes it possible to improve durability near the chassis fixed portion, which is the fixed portion between the chassis frame supporting the cargo bed and the cross member.

[0008] Furthermore, it is preferable that the fixing position between the first and second parts is located outboard of the outer end of the cross member in the vehicle width direction. With this configuration, the fixing position between the first and second parts does not overlap with the cross member, and the cross member does not suppress deformation of the fixing member, making the fixing member more likely to deform. As a result, the load can be more effectively released and stress near the chassis fixing portion can be further reduced.

[0009] Preferably, the fixing member extends along the bottom and side of the cargo bed, and the fixing position between the first and second parts is located below the bottom. With this configuration, the fixing position between the first and second parts can be located closer to the chassis fixing part than when the fixing position between the first and second parts is located on the side of the cargo bed, and the load input from the chassis frame to the cross member can be efficiently released at the fixing position.

[0010] Preferably, the first portion extends from a position more inward in the vehicle width direction than the chassis fixing portion to a position more inward in the vehicle width direction than the side of the cargo bed. With this configuration, the load input to the cross member at the chassis fixing portion can be received by the first portion extending on both sides in the vehicle width direction relative to the chassis fixing portion, and can then be efficiently released at the fixing position.

[0011] Preferably, the cross member, the first portion, and the second portion are arranged in this order from below: cross member, first portion, second portion. With this configuration, the load input to the cross member by the chassis fixing portion can be released while being transmitted to the first portion and then the second portion, thereby reducing the load transmitted directly from the cross member to the cargo bed and suppressing deformation of the bottom of the cargo bed.

[0012] Furthermore, it is preferable that the cargo bed includes a floor panel that defines a center portion of the bottom portion in the vehicle width direction, and side panels that are fixed to the floor panel and define outer ends and sides of the bottom portion in the vehicle width direction, and the chassis fixing portion is located below the side panels. With this configuration, the load transmitted to the chassis fixing portion is further transmitted to the side panels. In this way, by transmitting the load to the side panels, which have a relatively higher rigidity than the floor panel, deformation of the cargo bed can be suppressed.

[0013] The first portion is preferably located below the side panel. With this configuration, the load is transmitted from the first portion to the side panel, which has a relatively high rigidity, thereby suppressing deformation of the cargo bed.

[0014] Preferably, the cargo bed forms a wheel house in which wheels are placed, and the cross member and the fixing member are disposed adjacent to the wheel house on either side of the wheel house in the vehicle longitudinal direction. With this configuration, the load transmitted from the chassis frame to the cross member and fixing member is transmitted to the vicinity of the wheel house, which has a relatively high rigidity, thereby suppressing deformation of the cargo bed.

[0015] According to the vehicle cargo bed support structure of the present invention, it is possible to improve durability in the vicinity of the chassis fixing portion, which is the fixing portion between the chassis frame supporting the cargo bed and the cross member.

[0016] 1 is a perspective view showing a vehicle equipped with a cargo bed support structure according to an embodiment; FIG. 2 is a bottom view of the vehicle of FIG. 1; FIG. 3 is a perspective view showing the underside of the cargo bed; FIG. 4 is a cross-sectional view taken along line A-A of FIG. 2; FIG. 5 is an enlarged perspective view showing the area surrounded by the dashed line in FIG. 3; FIG. 6 is an exploded perspective view showing components of the support structure; FIG. 7 is a top view showing a cross member; FIG. 8 is a perspective view showing a reinforcement; FIG. 9 is a top view showing a first portion of a side post; FIG. 10 is a perspective view showing a second portion of a side post.

[0017] An embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a perspective view showing a vehicle equipped with a cargo bed support structure according to the embodiment. Fig. 2 is a bottom view of the vehicle shown in Fig. 1. Fig. 3 is a perspective view showing the bottom of the cargo bed. As shown in Fig. 1, the vehicle 1 is a so-called pickup truck including a cabin 2 provided at the front and a cargo bed 10 (cargo box) provided behind the cabin 2.

[0018] The cargo bed 10 includes a floor panel 11, a header board 12, a tailgate 13, and side panels 14. The floor panel 11 forms a central portion 10a1 (vehicle width central portion) of the bottom 10a of the cargo bed 10 in the vehicle width direction (the left-right direction of the coordinate axes in each figure). The header board 12 is attached to the front end of the floor panel 11 and forms the front wall of the cargo bed 10. The tailgate 13 is attached to the rear end of the floor panel 11 and forms the rear wall of the cargo bed 10. The side panels 14 are attached to both ends of the floor panel 11 in the vehicle width direction, respectively, and form the side portions 10b (side walls) of the cargo bed 10. The side panels 14 are also provided with arch-shaped wheel wells 14h that define a space in which wheels (not shown) of the vehicle 1 are arranged. The cargo bed 10 forms a storage space in which the space surrounded by the header board 12, tailgate 13, and side panels 14 is closed by the floor panel 11.

[0019] The structure of the side panels 14 will now be described. As shown in FIG. 3 , each side panel 14 includes a side inner panel 15 and a side outer panel 16. Note that the left side outer panel 16 in the vehicle width direction is omitted in FIG. 3 . The side inner panel 15 is configured as an L-shaped member when viewed from the vehicle front-rear direction (the front-rear direction of the coordinate axes in each drawing). The side inner panel 15 forms the end 10a2 (the outer end in the vehicle width direction) of the bottom 10a of the cargo bed 10 in the vehicle width direction and also forms the inner wall of the side portion 10b. Because the side inner panel 15 includes a portion curved to form an L-shape, it is a member with higher rigidity than the floor panel 11. The side outer panel 16 is arranged to cover the side inner panel 15 from the outside and is connected to the side inner panel 15 to form the outer wall of the side portion 10b of the cargo bed 10. The side inner panel 15 and the side outer panel 16 are provided with arch-shaped recesses at positions corresponding to each other, and these recesses form the wheel house 14h.

[0020] As shown in FIG. 2 , the vehicle 1 also includes multiple body frames for supporting the cabin 2 and the cargo bed 10. The body frames include a chassis frame 30, multiple cross members 32, and multiple side posts 34. The chassis frames 30 are located below the vehicle 1, and are provided in pairs on the left and right sides with a gap between them in the vehicle width direction, extending along the vehicle longitudinal direction. The chassis frames 30 are connected to each of the vehicle 1's wheels (not shown) via suspension devices (not shown). The multiple cross members 32 are located below the vehicle 1 with a gap between them in the vehicle longitudinal direction, and extend along the vehicle width direction. Each cross member 32 is bridged between the chassis frames 30 via a vibration-damping mount member (e.g., see mount member 90 in FIG. 4 ). The multiple side posts 34 are provided in pairs on the left and right sides, and one side post 34 is fixed to each of the outer ends of each cross member 32 in the vehicle width direction. As shown in Figure 3, each side post 34 has an L-shaped cross section when viewed from the fore-and-aft direction of the vehicle, extends along the bottom 10a and side 10b of the cargo bed 10, and is fixed to the outer end of the cross member 32 in the vehicle width direction and to the bottom 10a and side 10b, respectively.

[0021] Next, the bed support structure 20 of the vehicle 1 according to the embodiment will be described. In this embodiment, as shown in FIG. 3 , of the cross members 32 and side posts 34 provided adjacent to the wheel housing 14h, those disposed on the front side in the vehicle longitudinal direction are included in the bed support structure 20. In the following description, the cross members 32 included in the bed support structure 20 will be referred to as the "cross members 40," and the side posts 34 included in the bed support structure 20 will be referred to as the "side posts 60." The bed support structure 20 includes the chassis frame 30, the cross members 40, reinforcements 50 ( FIGS. 4 to 6 , and 8 ), the side posts 60 (fixing members), and mount members 90 ( FIG. 4 ).

[0022] FIG. 4 is a cross-sectional view taken along line A-A in FIG. 2. FIG. 5 is an enlarged perspective view showing the area surrounded by the dashed line in FIG. 3. FIG. 6 is an exploded perspective view showing the components of the cargo bed support structure 20. FIG. 7 is a top view showing the cross member 40. FIG. 8 is a perspective view showing the reinforcement 50. FIG. 9 is a top view showing a first portion of the side post 60. FIG. 10 is a perspective view showing a second portion of the side post 60. The coordinate axes in each figure represent the directions when each component of the cargo bed support structure 20 is applied to the vehicle 1.

[0023] The cross member 40 extends in the vehicle width direction above the chassis frame 30 along the bottom 10a and is fixed to both the chassis frame and the bottom 10a. As shown in FIG. 5 , an outer end 401 (outer end in the vehicle width direction) of the cross member 40 in the vehicle width direction is located below the side inner panel 15 that constitutes the bottom 10a of the cargo bed 10. As shown in FIGS. 4 to 7 , the cross member 40 includes a U-shaped portion 41 having a U-shaped cross section when viewed in the vehicle width direction, and two flange portions 42 extending forward and rearward in the vehicle longitudinal direction from each side portion 412 of the U-shaped portion 41. The cross member 40 is positioned so that the bottom portion 411 of the U-shaped portion 41 is located downward, and each flange portion 42 is fixed to the bottom 10a of the cargo bed 10 by fastening.

[0024] At the outer end 401 of the cross member 40, a mounting bolt insertion hole 40a, a first insertion hole 40b, and a second insertion hole 40c are formed in the bottom surface 411 of the U-shaped portion 41. As shown in FIG. 5 , the mounting bolt insertion hole 40a, the first insertion hole 40b, and the second insertion hole 40c are aligned in a straight line along the vehicle width direction and overlap in the vehicle front-rear direction. The first insertion hole 40b is positioned more inward in the vehicle width direction than the mounting bolt insertion hole 40a, and the second insertion hole 40c is positioned more outward in the vehicle width direction than the mounting bolt insertion hole 40a. A first distance L1 from the mounting bolt insertion hole 40a to the first insertion hole 40b is shorter than a second distance L2 from the mounting bolt insertion hole 40a to the second insertion hole 40c.

[0025] The reinforcements 50 are provided in a pair on the left and right sides, extend in the vehicle width direction along the bottom portion 10a above the cross member 40, and are fixed one to each of the outer end portions 401 of the cross member 40. As shown in Figures 4 to 6 and 8, the reinforcements 50 have a U-shaped cross section when viewed from the vehicle width direction, and are housed within the U-shaped portion 41 of the cross member 40 so that their bottom surface portion 511 abuts against the bottom surface portion 411 of the cross member 40. The outer end portion 501 of each reinforcement 50 in the vehicle width direction is positioned so as not to protrude outward in the vehicle width direction beyond the cross member 40.

[0026] 6 and 8, a mounting bolt insertion hole 50a, a first insertion hole 50b, and a second insertion hole 50c are formed in the bottom surface portion 511 of each reinforcement 50, corresponding to the mounting bolt insertion hole 40a, the first insertion hole 40b, and the second insertion hole 40c. The mounting bolt insertion holes 50a, the first insertion hole 50b, and the second insertion hole 50c are aligned in a straight line along the vehicle width direction at overlapping positions in the vehicle front-rear direction, and are arranged coaxially in the up-down direction with the corresponding mounting bolt insertion holes 40a, the first insertion hole 40b, and the second insertion hole 40c. A circular recessed mounting portion 52 is formed around the position where the mounting bolt insertion hole 50a is formed in the bottom surface portion 511.

[0027] The side posts 60 are provided in a pair, one on the left and one on the right, and are fixed to both outer ends 401 of the cross member 40. Each side post 60 includes a first portion 70 and a second portion 80, as shown in Figures 5 and 6 .

[0028] The first portion 70 extends in the vehicle width direction along the bottom 10a of the cargo bed 10 above the cross member 40 and the reinforcement 50. Specifically, the first portion 70 is located below the side inner panel 15 that constitutes the bottom 10a. As shown in FIG. 5 , the first portion 70 extends outward in the vehicle width direction from a position that is more inward in the vehicle width direction than the mounting bolt insertion hole 40a of the cross member 40, and extends to a position more inward in the vehicle width direction than the side end of the cargo bed 10 (the outer surface of the side inner panel 15). An outer end 701 in the vehicle width direction of the first portion 70 protrudes outward in the vehicle width direction further than the outer end 401 of the cross member 40 and the outer end 501 of the reinforcement 50.

[0029] As shown in Figures 4 to 6 and 9, the first part 70 includes a U-shaped portion 71 having a U-shaped cross section when viewed from the vehicle width direction, and two flange portions 72 extending from each side portion 712 of the U-shaped portion 71 to the front and rear in the vehicle longitudinal direction. The first part 70 has two abutment portions 711t protruding from a bottom surface 711 of the U-shaped portion 71. As shown in Figures 5 and 6, the U-shaped portion 71 of the first part 70 is housed within the reinforcement 50 so that the two abutment portions 711t abut against the bottom surface 511 of the reinforcement 50. Furthermore, the first part 70 is fixed to the bottom 10a of the cargo bed 10 by fastening together with the flange portion 42 of the cross member 40 at the two flange portions 72.

[0030] Furthermore, a mount insertion hole 70a, a first insertion hole 70b, and a second insertion hole 70c are formed in the bottom surface 711 of the U-shaped portion 71 of the first part 70, corresponding to the mount bolt insertion hole 40a, the first insertion hole 40b, and the second insertion hole 40c of the cross member 40. The mount insertion hole 70a, the first insertion hole 70b, and the second insertion hole 70c are aligned in a straight line along the vehicle width direction at overlapping positions in the vehicle front-rear direction, and are arranged coaxially in the up-down direction with the corresponding mount bolt insertion hole 40a, the first insertion hole 40b, and the second insertion hole 40c. The mount insertion hole 70a is a hole portion for inserting the first vibration damping member 91 of the mount member 90, and is formed with a larger diameter than the mount bolt insertion hole 40a.

[0031] As shown in Figures 5, 6, and 10, the second portion 80 is a member having an L-shaped cross section when viewed from the vehicle longitudinal direction. The second portion 80 extends above the first portion 70 along the bottom portion 10a and along the side portion 10b (the outer surface of the side inner panel 15) of the cargo bed 10. The second portion 80 includes a U-shaped portion 81 having a U-shaped cross section and two flange portions 82 extending forward and rearward in the vehicle longitudinal direction from each side portion 812 of the U-shaped portion 81. The U-shaped portion 81 and the two flange portions 82 are formed over the entire length of the second portion 80.

[0032] The second part 80 is fastened to the first part 70 by fastening the U-shaped part 81, which is housed within the outer end 501 of the first part 70 so that the bottom surface 811 of the U-shaped part 81 abuts against the bottom surface 711 of the first part 70. The first part 70 and the second part 80 are joined (fixed) together at spot welds 70d ( FIG. 5 ).

[0033] The fixing position 150 (i.e., the spot weld 70d) between the first portion 70 and the second portion 80 is located outboard of the outer end 401 of the cross member 40 in the vehicle width direction, and is located below the side inner panel 15 that constitutes the bottom portion 10a. The second portion 80 is also fixed to the bottom portion 10a and the side portion 10b of the cargo bed 10 by fastening at two flange portions 82. As described above, the cross member 40, the reinforcement 50, the first portion 70, and the second portion 80 (side post 60) are arranged in this order from the bottom: cross member 40, reinforcement 50, first portion 70 (side post 60), second portion 80 (side post 60).

[0034] As shown in FIG. 4 , the mount member 90 includes a first vibration-damping member 91 and a second vibration-damping member 92. The first vibration-damping member 91 and the second vibration-damping member 92 are cylindrically formed from an elastic material such as rubber. The first vibration-damping member 91 and the second vibration-damping member 92 have an insertion hole in their center through which a bolt 93 is inserted. The first vibration-damping member 91 is placed on the mounting portion 52 of the reinforcement 50 and is inserted into the bottom surface 711 of the first portion 70 of the side post 60 through a mount insertion hole 70 a formed in the first portion 70. Meanwhile, the second vibration-damping member 92 is placed on the upper surface of the chassis frame 30 so as to be aligned coaxially with the first vibration-damping member 91.

[0035] Bolts 93 are inserted into the first vibration-damping member and the second vibration-damping member 92 from the bottom 10a side of the cargo bed 10, and the bolts 93 are fastened to nuts 94 arranged on the underside of the chassis frame 30. The bolts 93 are inserted into the cross member 40, the reinforcement 50, and the first portion 70 of the side post 60 through the mount bolt insertion holes 40a, 50a and the mount insertion hole 70a. This fastens the chassis frame 30, the cross member 40, and the reinforcement 50 to one another via the mount member 90. Therefore, the locations where the mount bolt insertion holes 40a, 50a and the mount insertion hole 70a are formed become chassis fixing portions 100 to which the chassis frame 30, the cross member 40, and the reinforcement 50 are fixed, as shown in FIG. 5 .

[0036] The cross member 40, the reinforcement 50, and the first portion 70 of the side post 60 are fixed together by inserting bolts (not shown) into the first insertion holes 40b, 50b, and 70b and fastening the bolts to nuts (not shown). Therefore, the locations where the first insertion holes 40b, 50b, and 70b are formed form first fixing portions 110 where the cross member 40, the reinforcement 50, and the first portion 70 of the side post 60 are fixed together by fastening bolts (not shown). Furthermore, the cross member 40, the reinforcement 50, and the first portion 70 of the side post 60 are fixed together by inserting bolts (not shown) into the second insertion holes 40c, 50c, and 70c and fastening the bolts to nuts (not shown). Therefore, the locations where the second insertion holes 40c, 50c, and 70c are formed form second fixing portions 120 where the cross member 40, the reinforcement 50, and the first portion 70 are fixed together. It should be noted that the cross member 40, the reinforcement 50 and the first portion 70 may be connected by other methods such as welding.

[0037] The first fixing portion 110 is located more inward in the vehicle width direction than the chassis fixing portion 100, and the second fixing portion 120 is located more outward in the vehicle width direction than the chassis fixing portion 100. In other words, the first fixing portion 110 and the second fixing portion 120 are provided on both sides of the chassis fixing portion 100 in the vehicle width direction. Also, as described above, the mount bolt insertion holes 40a, 50a and the mount insertion hole 70a, the first insertion holes 40b, 50b, 70b and the second insertion holes 40c, 50c, 70c are aligned in a straight line along the vehicle width direction at overlapping positions in the vehicle fore-and-aft direction, and therefore the chassis fixing portion 100, the first fixing portion 110 and the second fixing portion 120 are also positioned at overlapping positions in the vehicle fore-and-aft direction. Furthermore, the distance from the chassis fixing part 100 to the first fixing part 110 corresponds to the first distance L1, and the distance from the chassis fixing part 100 to the second fixing part 120 corresponds to the second distance L2, with the first distance L1 being smaller than the second distance L2.

[0038] In the cargo bed support structure 20 configured as described above, the load transmitted from the wheels (not shown) to the chassis frame 30 is input to the cross member 40 and the reinforcement 50 via the mount member 90 at the chassis fixing portion 100. The load input to the cross member 40 and the reinforcement 50 is then transmitted from the first fixing portion 110 and the second fixing portion 120 to the first portion 70 of the side post 60, and is further transmitted from the first portion 70 to the second portion 80 at the fixing position 150.

[0039] As described above, in the cargo bed support structure 20 of the vehicle 1, the cross member 40 and the chassis frame 30 are fixed to each other by a chassis fixing portion 100 provided at the outer end 401 (outer end in the vehicle width direction) of the cross member 40, and the cross member 40 and the side post 60 (fixing member) are fixed to each other by a first fixing portion 110 located more inward in the vehicle width direction than the chassis fixing portion 100 and a second fixing portion 120 located more outward in the vehicle width direction than the chassis fixing portion 100.

[0040] With this configuration, the load input from the chassis frame 30 to the cross member 40 can be received by the first fixing portion 110 and the second fixing portion 120 provided on both sides of the chassis fixing portion 100 in the vehicle width direction. Therefore, compared to a case where the fixing position between the first portion 70 of the side post 60 and the cross member 40 is only on the outer side of the chassis fixing portion 100 in the vehicle width direction, the load can be efficiently released to the first portion 70 of the side post 60, making it possible to reduce stress generated near the chassis fixing portion 100. Therefore, with the cargo bed support structure 20 for the vehicle 1, it is possible to improve durability near the chassis fixing portion 100.

[0041] Furthermore, the side posts 60 extend along the bottom 10a and side 10b of the cargo bed 10, and the first fixing portion 110 and the second fixing portion 120 are located below the bottom 10a. This configuration increases the rigidity of the chassis fixing portion 100 on the outer side in the vehicle width direction, thereby improving durability, compared to, for example, a case in which the second fixing portion 120 is provided on the side 10b of the cargo bed 10. Note that, as long as the cross member 40 can extend to the side 10b of the cargo bed 10, the first fixing portion 110 and the second fixing portion 120 may be located laterally of the side 10b.

[0042] Additionally, the cross member 40 and the side post 60 are fastened to each other by bolts at the first fixing portion 110 and the second fixing portion 120. This configuration allows the cross member 40 and the side post 60 to be firmly fixed together. As mentioned above, the cross member 40 and the side post 60 may also be fixed together by other methods, such as welding.

[0043] Furthermore, the chassis fixing portion 100, the first fixing portion 110, and the second fixing portion 120 are also arranged in overlapping positions in the vehicle longitudinal direction. This configuration prevents the load input from the chassis frame 30 to the cross member 40 from being transmitted to a position offset in the vehicle longitudinal direction relative to the first portion 70 of the side post 60, thereby suppressing twisting of the cross member 40 and the side post 60. In other words, it is possible to improve the rigidity of the entire cross member 40 and the side post 60. Note that the chassis fixing portion 100, the first fixing portion 110, and the second fixing portion 120 may be arranged in offset positions in the vehicle longitudinal direction.

[0044] Furthermore, the first distance L1 from the chassis fixing portion 100 to the first fixing portion 110 and the second distance L2 from the chassis fixing portion 100 to the second fixing portion 120 are such that the first distance L1 (either one) is shorter than the second distance L2 (either one). This configuration allows the length of the side post 60 (first portion 70) on the first fixing portion 110 side (one side) located closer to the chassis fixing portion 100 to be relatively shorter. As a result, the rigidity of the side post 60 on the first fixing portion 110 side is increased, stably supporting the center side of the cargo bed 10 while also achieving weight reduction and improved yield. Note that the second distance L2 may be shorter than the first distance L1. This allows for stable support of the cargo bed 10 on the outer side in the vehicle width direction. The first distance L1 and the second distance L2 may be the same.

[0045] Furthermore, the reinforcement 50 is fixed to the cross member 40 by the chassis fixing portion 100, and is fixed to the first portion 70 by the first fixing portion 110 and the second fixing portion 120. In other words, the reinforcement 50 is provided within a range including the chassis fixing portion 100, the first fixing portion 110, and the second fixing portion 120 in the vehicle width direction, and is overlapped in the vertical direction with the cross member 40 and the first portion 70 of the side post 60. This configuration can further improve the durability of each member in the vicinity of the chassis fixing portion 100 and within a range including the first fixing portion 110 and the second fixing portion 120. Note that the reinforcement 50 may be provided only within a range including the chassis fixing portion 100. Alternatively, the reinforcement 50 may be omitted.

[0046] Furthermore, the cross member 40, the reinforcement 50, and the side post 60 are arranged in this order from below: cross member 40, reinforcement 50, side post 60. With this configuration, the reinforcement 50 is arranged adjacent to the cross member 40 to which the load is input from the chassis frame 30, thereby further improving the durability of the cross member 40. Note that the cross member 40, the reinforcement 50, and the side post 60 may be arranged in a different order.

[0047] The cargo bed 10 also includes a floor panel 11 that forms a central portion 10a1 (vehicle widthwise central portion) of the bottom portion 10a, and side inner panels 15 (side panels 14) that are fixed to the floor panel 11 and form end portions 10a2 (vehicle widthwise outer end portions) and side portions 10b of the bottom portion 10a. The chassis fixing portion 100, the first fixing portion 110, and the second fixing portion 120 are located below the side inner panels 15. With this configuration, the load transmitted to the chassis fixing portion 100, the first fixing portion 110, and the second fixing portion 120 is further transmitted to the side inner panels 15. In this way, by transmitting the load to the side inner panels 15, which have relatively higher rigidity than the floor panel 11, deformation of the cargo bed 10 can be suppressed. Note that the chassis fixing portion 100, the first fixing portion 110, and the second fixing portion 120 may be located below the floor panel 11.

[0048] The cargo bed 10 also defines wheel wells 14h in which the wheels are arranged, and the cross members 40 and side posts 60 are disposed adjacent to the wheel wells 14h, forward of the wheel wells 14h in the vehicle's fore-and-aft direction. With this configuration, the load transmitted from the chassis frame 30 to the cross members 40 and side posts 60 is transmitted to the vicinity of the wheel wells 14h, which have relatively high rigidity. This prevents deformation of the cargo bed 10. The cross members 40 and side posts 60 may be disposed adjacent to the wheel wells 14h, rearward of the wheel wells 14h in the vehicle's fore-and-aft direction, or may not be disposed adjacent to the wheel wells 14h.

[0049] Furthermore, in the cargo bed support structure 20 of the vehicle 1, the side post 60 includes a first part 70 fixed to the outer end 401 of the cross member 40, and a second part 80 fixed to the first part 70 outside the outer end 401 in the vehicle width direction.

[0050] With this configuration, because the side post 60 is divided into the first portion 70 and the second portion 80, the side post 60 is more likely to deform near the fixing position 150 between the first portion 70 and the second portion 80. As a result, the load input from the chassis fixing portion 100 to the cross member 40 and transmitted to the first portion 70 is efficiently released by the deformation of the side post 60, reducing stress generated near the chassis fixing portion 100. Furthermore, because the fixing position 150 between the first portion 70 and the second portion 80 does not overlap with the cross member 40, the cross member 40 does not suppress deformation of the side post 60, making the side post 60 more likely to deform. As a result, the load can be more effectively released, further reducing stress near the chassis fixing portion 100. Therefore, the cargo bed support structure 20 for the vehicle 1 can improve durability near the chassis fixing portion 100.

[0051] Furthermore, the side posts 60 extend along the bottom 10a and side 10b of the cargo bed 10, and the fixing positions 150 between the first and second portions 70 and 80 are located below the bottom 10a. With this configuration, the fixing positions 150 between the first and second portions 70 and 80 can be located closer to the chassis fixing parts 100 than when the fixing positions 150 are located on the side 10b of the cargo bed, and the load input from the chassis frame 30 to the cross member 40 can be efficiently released at the fixing positions 150. Note that the first portion 70 may be formed as an L-shaped member extending to the side 10b, and the fixing positions 150 between the first and second portions 70 and 80 may be located to the side of the side 10b.

[0052] Furthermore, the first portion 70 extends from a position more inward in the vehicle width direction than the chassis fixing portion 100 to a position more inward in the vehicle width direction than the side end of the cargo bed 10. With this configuration, the load input to the cross member 40 by the chassis fixing portion 100 is received by the first portion 70 extending on both sides of the chassis fixing portion 100 in the vehicle width direction, and can then be efficiently released at the fixing position 150. Note that the first portion 70 may be provided at a position more outward in the vehicle width direction than the chassis fixing portion 100.

[0053] Furthermore, the cross member 40, first portion 70, and second portion 80 are arranged in this order from the bottom up: cross member 40, first portion 70, second portion 80. With this configuration, the load input to the cross member 40 by the chassis fixing portion 100 can be released while being transmitted to the first portion 70 and then the second portion 80, thereby reducing the load transmitted directly from the cross member 40 to the cargo bed 10 and suppressing deformation of the cargo bed 10. Note that the cross member 40, first portion 70, and second portion 80 may be arranged in a different order.

[0054] Furthermore, the first portion 70 is located below the side inner panel 15 (side panel 14). With this configuration, the load is transmitted from the first portion 70 to the side inner panel 15, which has a relatively high rigidity, thereby suppressing deformation of the cargo bed 10. The chassis fixing portion 100 and the first portion 70 may also be located below the floor panel 11.

[0055] Although the description of the embodiment has been completed, aspects of the present invention are not limited to this embodiment. For example, the side posts 60 do not have to extend along the side portions 10b as long as they extend along the bottom portion 10a of the cargo bed 10. Also, the mounting members 90 may be omitted, and the chassis frame 30 and the cross member 40 may be fixed to each other by bolts or the like.

[0056] Furthermore, the fixing position 150 between the first portion 70 and the second portion 80 may be located outward in the vehicle width direction from the fixing portion between the cross member 40 and the first portion 70 (i.e., the second fixing portion 120) and inward in the vehicle width direction from the outermost end of the cross member 40 on the vehicle width direction. Even with this configuration, if the portion of the cross member 40 located outward in the vehicle width direction from the fixing position 150 is not fixed to any of the floor panel 11, the first portion 70, and the second portion 80, the deformation of the side post 60 can be utilized to reduce stress generated near the chassis fixing portion 100.

[0057] DESCRIPTION OF SYMBOLS 1 Vehicle 2 Cabin 10 Luggage bed 10a Bottom 10a1 Central portion (central portion in vehicle width direction) 10a2 End portion (outer end portion in vehicle width direction) 10b Side portion 11 Floor panel 14 Side panel 14h Wheelhouse 15 Side inner panel 20 Luggage bed support structure 30 Chassis frame 32, 40 Cross member 34, 60 Side post (fixing member) 40a, 50a Mount bolt insertion hole 40b, 50b, 70b First insertion hole 40c, 50c, 70c Second insertion hole 41, 71, 81 U-shaped portion 401, 501, 701 Outer end portion (outer end portion in vehicle width direction) 42, 72, 82 Flange portion 50 Reinforcement 52 Placement portion 70 First portion 70a Mount insertion hole 80 Second part 90 Mounting member 100 Chassis fixing part 110 First fixing part 120 Second fixing part 150 Fixing position L1 First distance L2 Second distance

Claims

1. a chassis frame located below the vehicle bed; a cross member extending in the vehicle width direction along the bottom of the loading platform and fixed to the chassis frame and the bottom of the loading platform; a fixing member extending in a vehicle width direction along the bottom of the loading platform and fixed to an outer end of the cross member in the vehicle width direction and to the bottom of the loading platform, The cross member and the chassis frame are fixed to each other with the chassis frame positioned below the cross member by a mount portion provided at the outer end of the cross member in the vehicle width direction, The vehicle cargo bed support structure includes a first portion fixed to the vehicle widthwise outer end of the cross member, and a second portion fixed to the first portion on the vehicle widthwise outer side of the fixing portion between the cross member and the first portion.

2. 2. The vehicle cargo bed support structure according to claim 1, wherein the fixing position of the first portion and the second portion is located outward in the vehicle width direction from the outer end of the cross member in the vehicle width direction.

3. the securing member extends along the bottom and sides of the cargo bed; The fixing position of the first part and the second part is located below the bottom part.

3. The vehicle loading platform support structure according to claim 1 or 2.

4. The vehicle loading platform support structure according to claim 1 , wherein the first portion extends from a position more inward in the vehicle width direction than the mount portion to a position more inward in the vehicle width direction than a side end of the loading platform.

5. 5. A vehicle cargo bed support structure as described in any one of claims 1 to 4, wherein the cross member, the first portion, and the second portion are arranged in the order of the cross member, the first portion, and the second portion from the bottom.

6. the loading platform includes a floor panel that defines a central portion of the bottom portion in the vehicle width direction, and side panels that are fixed to the floor panel and define outer ends and side portions of the bottom portion in the vehicle width direction, The mount portion is located below the side panel. The vehicle loading platform support structure according to any one of claims 1 to 5.

7. 7. The vehicle loading platform support structure according to claim 6, wherein the first portion is located below the side panel.

8. the loading platform forms a wheelhouse in which wheels are arranged, The cross member and the fixing member are disposed adjacent to the wheel house on either side of the wheel house in the vehicle front-rear direction. The vehicle loading platform support structure according to any one of claims 1 to 7.