Lower vehicle body floor structure and vehicle

Abstract

The lower vehicle body floor structure comprises a front wall plate, a front floor, a middle floor, a rear floor and a rear wall plate which are integrally formed, a front wall cross beam is integrally formed on the front side of the front wall plate, a seat cross beam is integrally formed above the front floor, and a rear floor cross beam is integrally formed below the rear floor. The front wall cross beam, the seat cross beam and the rear floor cross beam extend in the left-right direction of the vehicle body and are each provided with a left-right through cavity. According to the lower vehicle body floor structure, the dash panel, the front floor, the middle floor, the rear floor and the rear panel are integrally formed, the integration degree is high, the manufacturing precision of products can be guaranteed conveniently, the manufacturing efficiency of the products is improved, the structural strength of corresponding parts is enhanced through the arrangement of the front wall cross beam, the seat cross beam and the rear floor cross beam, and the service life of the lower vehicle body floor structure is prolonged. According to the structure, the overall strength, rigidity and durability of the floor structure are guaranteed, and the overall NVH performance of a vehicle is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of floor structures, and more specifically relates to a lower vehicle body floor structure and a vehicle. Background Art

[0002] The lower body floor is an important part of the vehicle body, generally including the front floor, middle floor and rear floor. Usually, there is a seat crossbeam on the front floor and a rear floor crossbeam on the rear floor. The seat crossbeam on the front floor is used to install the seats. The seat crossbeam can also strengthen the structure of the front floor area. The rear floor crossbeam is used to strengthen the structure of the rear floor, thereby improving the structural strength of the entire floor structure.

[0003] In the prior art, in order to improve the integrity of the floor structure, the front floor, middle floor and rear floor of some vehicles are processed in an integrated manner, and then the seat crossbeam, rear floor crossbeam, front panel and rear panel and other components are installed. When assembling the above components, multiple positioning and connection are required, and the processing accuracy of the components is high. The assembly takes a long time and is not conducive to the lightweight design of the vehicle. Utility Model Content

[0004] The utility model aims to provide an underbody floor structure and a vehicle, which can improve the integration degree of the floor structure, facilitate reducing the processing cost and realize lightweight design.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: to provide a lower vehicle body floor structure, including an integrally formed front panel, front floor, middle floor, rear floor and rear panel, the front side of the front panel is integrally formed with a front panel cross beam, the upper part of the front floor is integrally formed with a seat cross beam, and the lower part of the rear floor is integrally formed with a rear floor cross beam, the front panel cross beam, the seat cross beam and the rear floor cross beam extend in the left and right directions of the vehicle body respectively, and all have a through cavity that passes through from left to right.

[0006] In a possible implementation, a spare tire support plate is further provided between the rear floor and the rear panel, the rear floor protrudes upward from the spare tire support plate and the middle floor, and the middle floor protrudes upward from the front floor.

[0007] In some embodiments, the rear edge of the front floor is connected to the middle floor via an upper extension plate extending upward, the rear edge of the middle floor is connected to the rear floor via a connecting inclined plate extending obliquely rearward and upward, and the rear edge of the rear floor is connected to the spare tire tray via a lower extension plate extending downward.

[0008] In a possible implementation, the rear floor cross beam includes a rear floor middle cross beam connected under the rear floor and a rear floor rear cross beam, the rear floor middle cross beam is integrally formed on the rear side of the connecting inclined plate, and the rear floor rear cross beam is integrally formed on the front side of the lower extension plate.

[0009] In some embodiments, a middle floor front cross beam extending in the left-right direction is provided below the middle floor, and the middle floor front cross beam is also provided with a through cavity penetrating left and right, and the middle floor front cross beam is integrally formed on the rear side of the upper extension plate.

[0010] In some embodiments, reinforcing oblique ribs are respectively provided in the through cavities of the front cross beam of the middle floor, the middle cross beam of the rear floor, and the rear cross beam of the rear floor. The reinforcing oblique ribs are arranged to be inclined from bottom to top toward the front side or the rear side.

[0011] In a possible implementation, the front floor, the middle floor and the rear floor are all provided with reinforcement strips protruding upward and downward, the reinforcement strips extend left and right, and each reinforcement strip has a first weight-reducing cavity penetrating left and right.

[0012] In a possible implementation, the front panel is provided with a plurality of second weight-reducing cavities extending from left to right, and each second weight-reducing cavity is provided with a reinforcing rib.

[0013] In a possible implementation, a reinforcing transverse rib is provided in the through cavity of the front panel cross beam, and the plate surface of the reinforcing transverse rib is arranged in the horizontal direction; a reinforcing vertical rib is provided in the through cavity of the seat cross beam, and the plate surface of the reinforcing vertical rib is arranged in the vertical direction.

[0014] Compared with the prior art, the solution shown in the embodiment of the present application provides a lower vehicle body floor structure in which the front panel, front floor, middle floor, rear floor and rear panel are integrally formed as a single piece, with a high degree of integration, which is convenient for ensuring the manufacturing accuracy of the product and improving the manufacturing efficiency of the product. The arrangement of the front panel cross beam, seat cross beam and rear floor cross beam enhances the structural strength of the corresponding parts, meets the requirements of seat installation and structural reinforcement, eliminates the tediousness caused by subsequent separate installation, and improves the assembly efficiency. The above structure ensures the overall strength, rigidity and durability of the floor structure, improves the overall NVH performance of the vehicle, and improves the riding comfort of passengers.

[0015] The utility model also provides a vehicle, the vehicle comprising a lower vehicle floor structure. The floor structure of the vehicle is formed in an integrated manner, which improves the degree of integration. The integrated forming of components such as the front wall cross beam, the seat cross beam and the rear floor cross beam saves the tediousness of subsequent assembly, improves the NVH performance of the floor, and meets the comfort requirements of passengers. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 A schematic diagram of the structure of the lower vehicle body floor structure provided by an embodiment of the utility model;

[0018] Figure 2 For the utility model embodiment Figure 1 The partially enlarged structural diagram of middle Ⅰ;

[0019] Figure 3 For the utility model embodiment Figure 1 The schematic diagram of the partial enlarged structure of middle Ⅱ;

[0020] Figure 4 For the utility model embodiment Figure 1 A schematic diagram of the partially enlarged structure of middle III;

[0021] Figure 5 A schematic diagram of the front view of the lower vehicle body floor structure provided by an embodiment of the utility model;

[0022] Figure 6 For the utility model embodiment Figure 5 Schematic diagram of the partial enlarged structure of middle Ⅳ;

[0023] Among them, the reference numerals in the figure are:

[0024] 1. Front panel; 11. Front panel cross beam; 12. Second weight-reducing cavity; 13. Strengthening ribs; 2. Front floor; 21. Seat cross beam; 22. Upper extension plate; 3. Middle floor; 31. Connecting inclined plate; 32. Middle floor front cross beam; 4. Rear floor; 41. Lower extension plate; 42. Rear floor middle cross beam; 43. Rear floor rear cross beam; 5. Rear panel; 6. Spare tire support plate; 71. Strengthening oblique ribs; 72. Through cavity; 73. Strengthening strip; 74. First weight-reducing cavity; 75. Strengthening transverse ribs; 76. Strengthening vertical ribs. DETAILED DESCRIPTION

[0025] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0026] In the claims, specification and the above-mentioned drawings of the present utility model, the terms "front" and "rear" are the same as the front-to-back direction of the vehicle body, "left" and "right" are the same as the left-to-right direction of the vehicle body, and "up" and "down" are the same as the up-down direction of the vehicle body; the term "inside" refers to the direction toward the central axis of the vehicle body, and the term "outside" refers to the direction away from the central axis of the vehicle body, wherein the central axis of the vehicle body is parallel to the front-to-back direction of the vehicle body. The remaining directional words, unless otherwise clearly defined, such as the use of the terms "center", "lateral", "longitudinal", "horizontal", "vertical", "top", "bottom", "clockwise", "counterclockwise", "high", "low" and the like to indicate the direction or position relationship are based on the direction and position relationship shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, so they cannot be understood as limiting the specific protection scope of the present utility model.

[0027] Please also read Figures 1 to 6 The lower vehicle floor structure and the vehicle provided by the utility model are now described. The lower vehicle floor structure includes an integrally formed front panel 1, a front floor 2, a middle floor 3, a rear floor 4 and a rear panel 5. A front panel cross beam 11 is integrally formed at the front side of the front panel 1, a seat cross beam 21 is integrally formed above the front floor 2, and a rear floor cross beam is integrally formed below the rear floor 4. The front panel cross beam 11, the seat cross beam 21 and the rear floor cross beam extend in the left-right direction of the vehicle body respectively, and each has a through cavity 72 that passes through from left to right.

[0028] Compared with the prior art, the lower vehicle body floor structure provided in the present embodiment has a front panel 1, a front floor 2, a middle floor 3, a rear floor 4 and a rear panel 5, which are multiple components formed in one piece, and have a high degree of integration, which is convenient for ensuring the manufacturing accuracy of the product and improving the manufacturing efficiency of the product. The arrangement of the front panel cross beam 11, the seat cross beam 21 and the rear floor cross beam enhances the structural strength of the corresponding parts, meets the requirements of seat installation and structural reinforcement, eliminates the tediousness caused by subsequent separate installation, and improves the assembly efficiency. The above structure ensures the overall strength, rigidity and durability of the floor structure, improves the overall NVH performance of the vehicle, and improves the riding comfort of passengers.

[0029] In this embodiment, the front panel 1, the front floor 2, the middle floor 3, the rear floor 4 and the rear panel 5 are arranged in sequence from front to rear and formed in one piece, which improves the integrity of the floor structure. The front panel cross beam 11 strengthens the structure of the front panel 1, and the seat cross beam 21 not only meets the requirements for installing the front seats, but also strengthens the structure of the front floor 2. The design of the rear floor cross beam strengthens the structure of the rear floor 4, further improves the strength and rigidity of the floor structure, and improves the supporting performance of the floor structure.

[0030] When forming the above-mentioned body floor structure, an aluminum extrusion process should be used. The aluminum extrusion process is to first heat the aluminum alloy material and the aluminum bar blank with a circular or rectangular cross-sectional shape to 450℃ to 550℃ to improve its plasticity and fluidity, and then send the heated aluminum bar into the preheated mold cavity. Under the action of huge pressure, the aluminum bar blank continues to flow along the direction of the mold hole and passes through the mold hole, thereby realizing plastic deformation of the material, so that the aluminum bar blank is formed into a continuous long strip of aluminum profile with a predetermined cross-sectional shape and size. The above-mentioned forming method does not require the design of the draft angle, which effectively increases the layout space of the structure, optimizes space utilization, and realizes the reasonable layout of the structure.

[0031] Compared with the traditional stamping or die-casting molding method, the aluminum extrusion process can meet the different thickness requirements of different parts, and the cost of aluminum extrusion equipment is much lower than that of stamping or die-casting equipment. In addition, stamping or die-casting molding requires setting a draft angle, and it is difficult to obtain a cavity structure that passes through the cavity 72, so the use of aluminum extrusion technology can effectively reduce the cost of component molding.

[0032] The provision of the through cavity 72 on the front surround cross beam 11, the seat cross beam 21 and the rear floor cross beam facilitates structural weight reduction of the above components. The through cavity 72 penetrates in the left-right direction and can be synchronously formed through the aluminum extrusion process, which greatly reduces the material consumption of the components and effectively reduces the vehicle cost.

[0033] In one possible implementation, see Figure 1 and Figure 4 A spare tire support plate 6 is also provided between the rear floor 4 and the rear panel 5. The rear floor 4 protrudes upward from the spare tire support plate 6 and the middle floor 3, and the middle floor 3 protrudes upward from the front floor 2.

[0034] In this embodiment, in order to meet the need to install a spare tire in the trunk, a spare tire support plate 6 is integrally formed between the rear floor 4 and the rear panel 5. The spare tire support plate 6 is recessed downward to effectively avoid the upper space, thereby ensuring sufficient space in the trunk to meet subsequent storage needs.

[0035] The middle floor 3 is arranged to protrude upward from the front floor 2, and the rear floor 4 is arranged to protrude upward from the middle floor 3, so that the floor structure has a tendency to become higher from the front to the rear, meeting the layout requirements of the interior space. The spare tire support plate 6 is arranged below the front floor 2, so that the spare tire is in a sunken state when stored, so as to make full use of the space above the spare tire.

[0036] The front side edge of the spare tire support plate 6 is connected to the rear side edge of the rear floor 4, and the rear side edge of the spare tire support plate 6 is connected to the lower side edge of the rear panel 5. The spare tire support plate 6 is used to support the spare tire and has a high supporting strength.

[0037] In some embodiments, the above-mentioned front floor 2 is adopted as follows Figure 1 , Figures 4 to 5 See the structure shown. Figure 1 , Figures 4 to 5 The rear side edge of the front floor 2 is connected to the middle floor 3 through an upper extension plate 22 extending upward, the rear side edge of the middle floor 3 is connected to the rear floor 4 through a connecting inclined plate 31 extending obliquely upward and rearward, and the rear side edge of the rear floor 4 is connected to the spare tire support plate 6 through a lower extension plate 41 extending downward.

[0038] In this embodiment, the rear edge of the front floor 2 is connected to the front edge of the middle floor 3 through the upper extension plate 22. The plate surface of the upper extension plate 22 is perpendicular to the front and rear directions and extends upward to connect with the front edge of the middle floor 3, thereby lifting the height of the middle floor 3.

[0039] Similarly, the rear edge of the middle floor 3 is provided with a connecting inclined plate 31 connected to the rear floor 4, and the upper part of the connecting inclined plate 31 gradually extends backward and tilts to achieve effective connection with the rear floor 4. The rear edge of the rear floor 4 is provided with a lower extension plate 41 connected to the front edge of the spare tire support plate 6, and the plate surface of the lower extension plate 41 is perpendicular to the front-to-back direction, leaving sufficient placement space above the spare tire support plate 6, which is convenient for placing the spare tire. The above structure can be conveniently formed by aluminum extrusion process, with a high degree of integration, which helps to improve the forming efficiency of the floor structure.

[0040] In a possible implementation, the above-mentioned rear floor crossbeam adopts Figure 1 and Figure 4 See the structure shown. Figure 1 and Figure 4 The rear floor cross beam includes a rear floor middle cross beam 42 and a rear floor rear cross beam 43 connected to the bottom of the rear floor 4. The rear floor middle cross beam 42 is integrally formed on the rear side of the connecting inclined plate 31, and the rear floor rear cross beam 43 is integrally formed on the front side of the lower extension plate 41.

[0041] In this embodiment, by arranging a rear floor middle cross beam 42 and a rear floor rear cross beam 43 under the rear floor 4, the structures of different front and rear parts of the rear floor 4 can be strengthened respectively, thereby effectively improving the rigidity, strength and durability of the rear floor 4, improving the overall supporting performance of the rear floor 4, facilitating the extension of the component life, and meeting the durability requirements.

[0042] In some embodiments, the floor 3 in the above features is Figure 1 , Figures 5 and 6 See the structure shown. Figure 1 , Figures 5 and 6 A middle floor front cross beam 32 extending in the left-right direction is provided below the middle floor 3 . The middle floor front cross beam 32 is also provided with a through cavity 72 passing through the left and right directions. The middle floor front cross beam 32 is integrally formed at the rear side of the upper extension plate 22 .

[0043] In this embodiment, a middle floor front cross beam 32 is provided at the front of the middle floor 3. Since a rear floor middle cross beam 42 is provided at the position where the rear side of the middle floor 3 and the rear floor 4 meet, structural reinforcement can be performed only at the position where the front side of the middle floor 3 and the front floor 2 meet. The middle floor front cross beam 32 is raised to the rear side of the upper extension plate 22, so that the space under the middle floor 3 can be fully utilized to avoid extra space occupation.

[0044] In some embodiments, the front floor beam 32, the middle floor beam 42 and the rear floor beam 43 in the above-mentioned features are formed as follows: Figures 1 to 6 See the structure shown. Figures 1 to 6 Reinforcing oblique ribs 71 are respectively provided in the through cavities 72 of the middle floor front cross beam 32, the rear floor middle cross beam 42 and the rear floor rear cross beam 43. The reinforcing oblique ribs 71 are arranged to be inclined from bottom to top toward the front side or the rear side.

[0045] In this embodiment, the middle floor front cross beam 32 below the middle floor 3 and the rear floor middle cross beam 42 and rear floor rear cross beam 43 below the rear floor 4 are all provided with left and right through-holes. By arranging reinforcing diagonal ribs 71 in the above-mentioned through holes, the structural strength of the components can be effectively enhanced, and reliable support for the middle floor 3 and the rear floor 4 can be achieved. Under the premise of basically not increasing the weight of the components, the overall strength of the entire floor structure is increased and its bearing capacity is improved.

[0046] In a possible implementation, the front floor 2, the middle floor 3 and the rear floor 4 are configured as follows: Figure 1 , Figure 3 , Figure 4 and Figure 6 See the structure shown. Figure 1 , Figure 3 , Figure 4 and Figure 6 The front floor 2, the middle floor 3 and the rear floor 4 are all provided with reinforcement strips 73 protruding upward and downward. The reinforcement strips 73 extend left and right, and each reinforcement strip 73 has a first weight-reducing cavity 74 that runs through left and right.

[0047] In this embodiment, a plurality of reinforcing strips 73 are evenly distributed on the front floor 2, the middle floor 3 and the rear floor 4. The plurality of reinforcing strips 73 extend in the left-right direction and are arranged at intervals in the front-back direction. The intervals between two adjacent reinforcing strips 73 are equal. In the area of ​​the front floor 2 provided with the seat cross beam 21, the area of ​​the middle floor 3 provided with the middle floor front cross beam 32, and the area of ​​the rear floor 4 provided with the rear floor middle cross beam 42 and the rear floor rear cross beam 43, it is not necessary to provide the reinforcing strips 73. The reinforcing strips 73 and the seat cross beam 21, the middle floor front cross beam 32, the rear floor middle cross beam 42 and the rear floor rear cross beam 43 can all play a role in reinforcing the floor structure.

[0048] The first weight-reducing cavity 74 provided inside the reinforcing strip 73 is convenient for reducing the material consumption of the reinforcing strip 73, reducing its structural weight, and realizing a lightweight design. The cross-sections of the reinforcing strip 73 and the first weight-reducing cavity 74 can be respectively set to different structures such as rectangle, trapezoid, circle or triangle, and the cross-sections of the reinforcing strip 73 and the first weight-reducing cavity 74 can also be set to different cross-sectional shapes, which can realize a structural reinforcement effect.

[0049] As a specific embodiment, the cross-section of the reinforcement strip 73 is circular, the cross-section of the first weight reduction cavity 74 is also circular, the radius of the first weight reduction cavity 74 is 5 mm, the wall thickness of the first weight reduction cavity 74 is 1 mm or 2 mm, and the spacing between two adjacent reinforcement strips 73 is 30 mm, which can effectively improve the rigidity of the floor structure, while improving the sound absorption performance and seismic resistance of the floor structure.

[0050] It can be seen that the provision of the reinforcing strip 73 can improve the NVH performance of the floor structure, eliminate the provision of the damping rubber plate, and improve the comfort of passengers. On this basis, the spare tire support plate 6 is also provided with a reinforcing strip 73, which can also improve the structural strength of the spare tire support plate 6 and ensure that the spare tire support plate 6 effectively supports the spare tire.

[0051] In a possible implementation, the above-mentioned characteristic front panel 1 adopts Figure 1 to Figure 2 See the structure shown. Figure 1 to Figure 2 The front panel 1 is provided with a plurality of second weight-reducing cavities 12 which pass through the left and right sides, and each second weight-reducing cavity 12 is provided with a reinforcing rib 13 .

[0052] In this embodiment, the front panel 1 has a relatively large thickness. By providing a second weight-reducing cavity 12 that runs through the front panel 1 from left to right, the material consumption of the front panel 1 is reduced while satisfying the structural strength of the front panel 1. Since the front panel 1 has a certain height in the vertical direction, a plurality of second weight-reducing cavities 12 are provided at intervals in the vertical direction to avoid delamination of the front panel 1 caused by the second weight-reducing cavity 12 being too large.

[0053] The second weight-reducing cavity 12 has a rectangular cross section, and the reinforcing ribs 13 are connected between two diagonal corners of the second weight-reducing cavity 12, which helps to improve the noise isolation effect in the cabin and enhance the rigidity of the front panel 1. The front panel 1 is formed by extrusion of aluminum profiles. Based on the high damping characteristics of aluminum, it is easy to reduce the vibration transmitted by the engine and the road surface, thereby improving the NVH performance of the vehicle.

[0054] In a possible implementation, the above-mentioned characteristic front wall cross beam 11 adopts Figures 1 to 3 See the structure shown. Figures 1 to 3 A reinforcing transverse rib 75 is provided in the through cavity 72 of the front enclosure cross beam 11, and the plate surface of the reinforcing transverse rib 75 is arranged in the horizontal direction. A reinforcing vertical rib 76 is provided in the through cavity 72 of the seat cross beam 21, and the plate surface of the reinforcing vertical rib 76 is arranged in the vertical direction.

[0055] In this embodiment, the reinforcing transverse ribs 75 of the front panel cross beam 11 and the reinforcing vertical ribs 76 of the seat cross beam 21 can support the interior of the through cavity 72 in corresponding directions, which is convenient for structural forming through an aluminum extrusion process. It can have a structural reinforcement effect on the front panel cross beam 11 or the seat cross beam 21, thereby ensuring the seat installation requirements and the structural strength requirements of the front panel 1.

[0056] As a specific embodiment, the thickness of the front floor 2, the middle floor 3, the rear floor 4 and the spare tire tray 6 are all 1 mm, the wall thickness of the seat cross beam 21, the middle floor 3 cross beam, the rear floor middle cross beam 42 and the rear floor rear cross beam 43 are respectively 2 mm, the thickness of the reinforcing diagonal ribs 71, the reinforcing vertical ribs 76 and the reinforcing transverse ribs 75 are all 1 mm, and the above parameters can meet the strength requirements of the floor structure.

[0057] Based on the same inventive concept, the embodiment of the present application further provides a vehicle, the vehicle comprising a lower vehicle floor structure. The floor structure of the vehicle is formed in one piece, which improves the degree of integration. The one-piece forming of the front wall cross beam 11, the seat cross beam 21 and the rear floor cross beam saves the tediousness of subsequent assembly, improves the NVH performance of the floor, and meets the comfort requirements of passengers.

[0058] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. The lower vehicle body floor structure is characterized by: The invention comprises an integrally formed front panel (1), a front floor (2), a middle floor (3), a rear floor (4) and a rear panel (5); a front panel cross beam (11) is integrally formed on the front side of the front panel (1); a seat cross beam (21) is integrally formed above the front floor (2); a rear floor cross beam is integrally formed below the rear floor (4); the front panel cross beam (11), the seat cross beam (21) and the rear floor cross beam respectively extend in the left-right direction of the vehicle body and each has a through cavity (72) that penetrates from left to right.

2. The lower vehicle body floor structure according to claim 1, characterized in that: A spare tire support plate (6) is also provided between the rear floor (4) and the rear panel (5); the rear floor (4) protrudes upward from the spare tire support plate (6) and the middle floor (3); and the middle floor (3) protrudes upward from the front floor (2).

3. The lower vehicle body floor structure according to claim 2, characterized in that: The rear side edge of the front floor (2) is connected to the middle floor (3) via an upwardly extending upper extension plate (22), the rear side edge of the middle floor (3) is connected to the rear floor (4) via a connecting inclined plate (31) extending obliquely rearward and upward, and the rear side edge of the rear floor (4) is connected to the spare tire support plate (6) via a downwardly extending lower extension plate (41).

4. The lower vehicle body floor structure according to claim 3, characterized in that: The rear floor cross beam comprises a rear floor middle cross beam (42) and a rear floor rear cross beam (43) connected below the rear floor (4); the rear floor middle cross beam (42) is integrally formed on the rear side of the connecting inclined plate (31); and the rear floor rear cross beam (43) is integrally formed on the front side of the lower extension plate (41).

5. The lower vehicle body floor structure according to claim 4, characterized in that: A middle floor front cross beam (32) extending in the left-right direction is provided below the middle floor (3), and the middle floor front cross beam (32) is also provided with a through cavity (72) penetrating the left and right sides. The middle floor front cross beam (32) is integrally formed on the rear side of the upper extension plate (22).

6. The lower vehicle body floor structure according to claim 5, characterized in that: Reinforcing oblique ribs (71) are respectively provided in the through cavities (72) of the front cross beam (32) of the middle floor, the middle cross beam (42) of the rear floor and the rear cross beam (43) of the rear floor. The reinforcing oblique ribs (71) are arranged to be inclined from bottom to top toward the front side or the rear side.

7. The lower vehicle body floor structure according to any one of claims 1 to 6, characterized in that: The front floor (2), the middle floor (3) and the rear floor (4) are all provided with reinforcement strips (73) protruding upward and downward. The reinforcement strips (73) extend left and right, and each reinforcement strip (73) has a first weight-reducing cavity (74) penetrating left and right.

8. The lower vehicle body floor structure according to any one of claims 1 to 6, characterized in that: The front panel (1) is provided with a plurality of second weight-reducing cavities (12) which pass through the left and right sides, and each of the second weight-reducing cavities (12) is provided with a reinforcing rib (13).

9. The lower vehicle body floor structure according to any one of claims 1 to 6, characterized in that: A reinforcing transverse rib (75) is provided in the through cavity (72) of the front enclosure cross beam (11), and the plate surface of the reinforcing transverse rib (75) is arranged in the horizontal direction; a reinforcing vertical rib (76) is provided in the through cavity (72) of the seat cross beam (21), and the plate surface of the reinforcing vertical rib (76) is arranged in the vertical direction.

10. A vehicle, characterized in that: The invention comprises the lower vehicle body floor structure according to any one of claims 1 to 9.

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