Two-seat up-and-down double closed loop body structure and vehicle

Abstract

The application relates to a two-seater upper and lower double-closed-loop vehicle body structure and a vehicle, and relates to the technical field of vehicle body structures. The vehicle body structure comprises a passenger cabin closed loop structure and a floor closed loop structure; the passenger cabin closed loop structure is sequentially and circularly connected in a head-to-tail mode by a roof rear cross beam, a left C column, a rear wall and a right C column to form an enclosure; the floor closed loop structure comprises a seat cross beam, a C ring cross beam, a rear cross beam, a left longitudinal beam and a right longitudinal beam, three cross beams are arranged at intervals from front to back and are connected with the two longitudinal beams to form a closed loop; and the two closed loop structures are rigidly connected to form a double-closed-loop bearing system. The application realizes the continuous transmission of loads in multiple paths, greatly improves the overall torsional and bending stiffness of the vehicle body, simultaneously replaces scattered reinforcement with a closed loop mechanical structure, significantly enhances the collision safety and structural durability under the premise of ensuring lightweight.

Description

Technical Field

[0001] This application relates to the field of vehicle body structure technology, specifically to a dual closed-loop body structure for a two-seat vehicle and the vehicle itself. Background Technology

[0002] With the increasing popularity of two-seater vehicles for short-distance commuting and micro-commuting, the requirements for four indicators of vehicle body lightweighting, structural rigidity, collision safety, and manufacturing cost have increased simultaneously. However, the short wheelbase, narrow lateral width of the cabin, and compact chassis layout of two-seater models severely limit the space available for the effective load-bearing frame of the vehicle body.

[0003] Currently, the mainstream body load-bearing structures for two-seater passenger vehicles in China are mainly divided into three categories: open floor frame structure, single closed-loop passenger compartment structure, and single closed-loop structure with local reinforcement. Among them, the single closed-loop structure with local reinforcement is the most widely used structure in the industry. However, existing technologies generally have the following common problems: 1. The load transfer of the single closed-loop body is discontinuous, with insufficient stiffness margin and weak resistance to deformation; 2. In order to improve stiffness, a large number of scattered reinforcing plates are often added, resulting in increased body weight and an inability to reconcile the contradiction between weight reduction and strength; 3. Collision load transfer is not smooth, and the passenger compartment is prone to large intrusion under side collision and roof crush conditions, which limits the passive safety protection level; 4. There are many scattered reinforcing parts, which are difficult to weld and process, resulting in high production costs and poor structural durability and reliability. Summary of the Invention

[0004] In view of this, the purpose of this application is to provide a two-seater vehicle with an upper and lower double closed-loop body structure and vehicle, so as to solve at least one of the above-mentioned technical problems.

[0005] In a first aspect, this application provides a dual closed-loop body structure for a two-seater vehicle, comprising: a passenger compartment closed-loop structure, which includes a roof rear crossbeam, a left C-pillar, a rear panel, and a right C-pillar, the roof rear crossbeam, the left C-pillar, the rear panel, and the right C-pillar being sequentially connected end-to-end to form the passenger compartment closed-loop structure; and a floor closed-loop structure, which includes a seat crossbeam, a C-ring crossbeam, a rear crossbeam, a left longitudinal beam, and a right longitudinal beam, the seat crossbeam, the C-ring crossbeam, and the rear crossbeam being sequentially spaced from front to back along the length of the vehicle body and connected to the left and right longitudinal beams to jointly form the floor closed-loop structure; wherein, the passenger compartment closed-loop structure and the floor closed-loop structure are rigidly connected to form a dual closed-loop load-bearing system.

[0006] In conjunction with the first aspect, in some optional embodiments, the rear end of the left longitudinal beam is provided with a left longitudinal beam connecting plate that closes its rear end face and is connected to the rear enclosure through the left longitudinal beam connecting plate, and the rear end of the right longitudinal beam is provided with a right longitudinal beam connecting plate that closes its rear end face and is connected to the rear enclosure through the right longitudinal beam connecting plate.

[0007] In conjunction with the first aspect, some optional embodiments also include a left rear wheel cover and a right rear wheel cover, with the left C-pillar, the left end of the C-ring beam, and the left longitudinal beam intersecting and connected through the left rear wheel cover, and the right C-pillar, the right end of the C-ring beam, and the right longitudinal beam intersecting and connected through the right rear wheel cover.

[0008] In conjunction with the first aspect, in some optional embodiments, the left C-pillar includes a connected left C-pillar inner panel and a left C-pillar outer panel, the left C-pillar inner panel being connected to the left end of the C-ring crossbeam and the left longitudinal beam via the left rear wheel arch; the right C-pillar includes a connected right C-pillar inner panel and a right C-pillar outer panel, the right C-pillar inner panel being connected to the right end of the C-ring crossbeam and the right longitudinal beam via the right rear wheel arch.

[0009] In conjunction with the first aspect, some alternative embodiments also include a rear floor, the edges of which are connected to the rear bulkhead, seat crossbeam, left longitudinal beam and right longitudinal beam respectively, and the surface of the rear floor is connected to the C-ring crossbeam and the rear crossbeam.

[0010] In conjunction with the first aspect, in some alternative embodiments, the C-ring crossbeam is connected to the upper surface of the left longitudinal beam, the upper surface of the rear floor, and the upper surface of the right longitudinal beam, respectively.

[0011] In conjunction with the first aspect, in some optional embodiments, the rear crossbeam includes an upper rear crossbeam plate and a lower rear crossbeam plate, the upper rear crossbeam plate and the lower rear crossbeam plate are arranged opposite each other along the vehicle height direction, the upper rear crossbeam plate is connected to the upper surface of the rear floor, the lower rear crossbeam plate is connected to the lower surface of the rear floor, and both ends of the upper rear crossbeam plate and the lower rear crossbeam plate are respectively connected to the left longitudinal beam and the right longitudinal beam.

[0012] In conjunction with the first aspect, in some optional embodiments, the left longitudinal beam includes a left longitudinal beam upper plate and a left longitudinal beam lower plate connected together, the front ends of the left longitudinal beam upper plate and the front ends of the left longitudinal beam lower plate being connected to the upper surface and the lower surface of the seat crossbeam, respectively; the right longitudinal beam includes a right longitudinal beam upper plate and a right longitudinal beam lower plate connected together, the front ends of the right longitudinal beam upper plate and the front ends of the right longitudinal beam lower plate being connected to the upper surface and the lower surface of the seat crossbeam, respectively.

[0013] In conjunction with the first aspect, in some alternative embodiments, the floor closing ring structure further includes a left sill rear connecting plate and a right sill rear connecting plate, the left sill rear connecting plate being connected to the front end side of the left longitudinal beam and the left end of the seat crossbeam, respectively, and the right sill rear connecting plate being connected to the front end side of the right longitudinal beam and the right end of the seat crossbeam, respectively.

[0014] Secondly, this application provides a vehicle including a two-seat vehicle with an upper and lower double closed-loop body structure in any of the embodiments of the first aspect described above.

[0015] Based on the above technical solution, the two-seater vehicle body structure and vehicle provided in this application form a double-layered, interconnected force transmission channel by constructing a double-closed-loop load-bearing system that rigidly connects the passenger compartment closed loop and the floor closed loop. Torsional, bending, and impact loads can be simultaneously and rapidly distributed and transmitted within the double closed loop, eliminating stress discontinuities and significantly improving the torsional and bending stiffness of the entire vehicle from the structural root, reducing driving deformation, and improving NVH (Noise, Vibration, Harshness) and handling. Simultaneously, relying on the high load-bearing efficiency of the double-closed-loop topology, the mechanical advantages of the closed loop itself replace scattered reinforcements, reducing material volume and sheet thickness while ensuring stiffness, breaking through the bottleneck that increased stiffness inevitably leads to increased weight, and achieving lightweighting. Furthermore, the double closed loop can disperse impact energy through multiple paths, avoiding localized stress accumulation and significantly improving the passenger compartment's intrusion resistance and collision safety. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the upper and lower double closed-loop body structure of a two-seater vehicle provided in an embodiment of this application, viewed from the front side.

[0018] Figure 2 This is a schematic diagram of the upper and lower double closed-loop body structure of a two-seater vehicle provided in an embodiment of this application, viewed from the rear side.

[0019] Figure 3 This is a schematic diagram of a crew cabin closed loop structure provided in an embodiment of this application.

[0020] Figure 4 This is a schematic diagram of a floor closed-loop structure provided in an embodiment of this application from a top-down perspective.

[0021] Figure 5 This is a schematic diagram of a floor closed loop structure provided in an embodiment of this application from an upward viewing angle.

[0022] Attached reference numerals: 100, Upper and lower double closed-loop body structure; 10, Passenger compartment closed-loop structure; 11, Rear crossbeam of roof; 12, Left C-pillar; 121, Left C-pillar outer panel; 13, Rear bulkhead; 14, Right C-pillar; 141, Right C-pillar inner panel; 142, Right C-pillar outer panel; 20, Floor closed-loop structure; 21, Seat crossbeam; 22, C-ring crossbeam; 23, Rear crossbeam; 231, Rear crossbeam upper section. 232. Lower plate of rear crossbeam; 24. Left longitudinal beam; 241. Upper plate of left longitudinal beam; 242. Lower plate of left longitudinal beam; 243. Connecting plate of left longitudinal beam; 25. Right longitudinal beam; 251. Upper plate of right longitudinal beam; 252. Lower plate of right longitudinal beam; 253. Connecting plate of right longitudinal beam; 26. Rear connecting plate of left sill; 27. Rear connecting plate of right sill; 30. Left rear wheel cover; 40. Right rear wheel cover; 50. Rear floor. Detailed Implementation

[0023] The specific embodiments of this application will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely a part of the embodiments of this application, and not all of them. Based on the description of this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0024] In the description of this application, unless otherwise expressly specified and limited, the terms "connection," "setup," "installation," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0025] The terms “upper,” “lower,” “left,” “right,” “front,” “back,” “center,” “top,” “bottom,” “inner,” “outer,” “vertical,” “horizontal,” “clockwise,” “counterclockwise,” “axial,” “radial,” and “circumferential” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of description and simplification, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0026] The terms “first,” “second,” “third,” etc., are used only to distinguish elements with similar properties, and do not indicate or imply relative importance or a specific order, unless otherwise explicitly stated or limited.

[0027] The terms “comprising,” “including,” “having,” or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0028] The term "multiple" means two or more (including two).

[0029] The term "and / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three cases: A exists alone, A and B exist simultaneously, and B exists alone.

[0030] The terms "an embodiment," "as an example," and "in one implementation" refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which may be included in at least one embodiment or example of this application. These illustrative expressions do not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Where there is no conflict, the embodiments and features described in these embodiments can be combined in a suitable manner.

[0031] like Figures 1 to 5 As shown, this application embodiment provides a two-seat vehicle with an upper and lower double closed-loop body structure 100, including a passenger compartment closed-loop structure 10 and a floor closed-loop structure 20.

[0032] like Figure 3 As shown, the passenger compartment closed-loop structure 10 includes a rear crossbeam 11, a left C-pillar 12, a rear bulkhead 13, and a right C-pillar 14. The rear crossbeam 11, left C-pillar 12, rear bulkhead 13, and right C-pillar 14 are connected end-to-end to form the passenger compartment closed-loop structure 10. The passenger compartment closed-loop structure 10 mainly bears static pressure on the top of the vehicle body, torsion loads on the vehicle body, and impact loads from the rear of the vehicle, achieving overall pressure bearing and deformation constraint of the upper space.

[0033] like Figure 4 and Figure 5As shown, the floor closed-loop structure 20 includes a seat crossbeam 21, a C-ring crossbeam 22, a rear crossbeam 23, a left longitudinal beam 24, and a right longitudinal beam 25. The seat crossbeam 21, C-ring crossbeam 22, and rear crossbeam 23 are arranged sequentially from front to back along the length of the vehicle body, and connect with the left longitudinal beam 24 and the right longitudinal beam 25 to form the floor closed-loop structure 20. The left longitudinal beam 24 and right longitudinal beam 25 run through the front and rear sections of the vehicle body along its length and are symmetrically arranged in the width direction, serving as the longitudinal core load-bearing structure of the entire vehicle. The seat crossbeam 21, C-ring crossbeam 22, and rear crossbeam 23, as three crossbeams, are rigidly fixed to the left and right longitudinal beams at both ends, forming a regular grid-shaped basic framework. The floor closed-loop structure 20 mainly bears the loads from side impacts, vehicle body bending, and chassis bumps, achieving full-area distribution of the lower load.

[0034] The passenger compartment closed-loop structure 10 and the floor closed-loop structure 20 are rigidly connected through connecting nodes, forming an upper and lower double closed-loop load-bearing system. Based on the principle of double-layer closed-loop synergistic force bearing, when the vehicle is subjected to external forces in any direction, the load can be simultaneously incorporated into the double closed-loop load-bearing system, uniformly transmitted and gradually dissipated along the circumference of the closed loop, without being concentrated in a single member or single point. The two closed-loop structures support and constrain each other, canceling out deformation trends and maximizing the suppression of body torsion and bending deformation, achieving a high-rigidity load-bearing effect. Furthermore, relying on the high load-bearing efficiency of the double closed-loop topology, the large number of scattered reinforcing plates in traditional solutions can be eliminated. The mechanical load-bearing advantages of the closed-loop structure itself can replace superimposed reinforcement. High-strength steel is used in the main load-bearing members of the closed loop, and the cross-sectional materials in non-critical areas are simplified, eliminating the need to rely on thicker plates for strength and achieving lightweight design.

[0035] Regarding the connection nodes of the upper and lower closed loop structures: (e.g.) Figures 1 to 3 As shown, the upper and lower double closed-loop body structure 100 also includes a left rear wheel arch 30 and a right rear wheel arch 40. The left C-pillar 12, the left end of the C-ring crossbeam 22, and the left longitudinal beam 24 are connected by the left rear wheel arch 30, specifically through the inner panel of the left rear wheel arch 30; the right C-pillar 14, the right end of the C-ring crossbeam 22, and the right longitudinal beam 25 are connected by the right rear wheel arch 40, specifically through the inner panel of the right rear wheel arch 40. The left rear wheel arch 30 and the right rear wheel arch 40 serve as a transfer hub structure connecting the two closed-loop structures, allowing side collision energy to be quickly transferred from the upper C-pillar to the longitudinal beams and C-ring crossbeams of the lower floor closed loop, achieving rapid load unloading.

[0036] The left C-pillar 12 comprises a connected inner plate (obscured in the figure) and an outer plate 121. The inner plate is connected to the left end of the C-ring beam 22 and the left longitudinal beam 24 via the left rear wheel arch 30. The right C-pillar 14 comprises a connected inner plate 141 and an outer plate 142. The inner plate 141 is connected to the right end of the C-ring beam 22 and the right longitudinal beam 25 via the right rear wheel arch 40. The closed section formed by the inner and outer plates of the C-pillars intersects with the rear wheel arch through the inner plate, ensuring direct force transmission of the core load-bearing frame and improving fatigue crack resistance.

[0037] Regarding the overlap relationship between the floor closed loop structure 20 and the rear floor 50: (e.g.) Figure 4 and Figure 5 As shown, the upper and lower double closed-loop body structure 100 also includes a rear floor 50. The edges of the rear floor 50 are connected to the rear bulkhead 13, seat crossbeam 21, left longitudinal beam 24, and right longitudinal beam 25, respectively. The surface of the rear floor 50 is connected to the C-ring crossbeam 22 and the rear crossbeam 23. The rear floor 50, as a large-area skin, is fully fitted and connected to the left and right longitudinal beams and the three crossbeam frames to form the floor structure. The mechanical load-bearing advantage of the closed-loop structure itself replaces the need for superimposed reinforcement.

[0038] The C-ring crossbeam 22 is connected to the upper surface of the left longitudinal beam 24, the upper surface of the rear floor 50, and the upper surface of the right longitudinal beam 25. The C-ring crossbeam 22 straddles the longitudinal beams and the rear floor, forming a stable support surface and ensuring balanced force distribution on both sides.

[0039] The rear crossbeam 23 includes an upper rear crossbeam plate 231 and a lower rear crossbeam plate 232. The upper and lower rear crossbeam plates 231 and 232 are arranged opposite each other along the vehicle height direction. The upper rear crossbeam plate 231 is connected to the upper surface of the rear floor 50, and the lower rear crossbeam plate 232 is connected to the lower surface of the rear floor 50. Both ends of the upper and lower rear crossbeam plates 231 and 232 are connected to the left longitudinal beam 24 and the right longitudinal beam 25, respectively. This structure, in which the upper and lower plates sandwich the rear floor, greatly enhances the torsional stiffness of the rear crossbeam area, effectively reducing the material volume and plate thickness under the same strength requirements, thus achieving structural weight reduction.

[0040] Regarding the reinforcement of the front closing node of the floor closed loop structure 20: (e.g.) Figure 4 and Figure 5As shown, the left longitudinal beam 24 includes a connected upper left longitudinal beam plate 241 and a lower left longitudinal beam plate 242. The front ends of the upper left longitudinal beam plate 241 and the lower left longitudinal beam plate 242 are connected to the upper and lower surfaces of the seat crossbeam 21, respectively. The right longitudinal beam 25 includes a connected upper right longitudinal beam plate 251 and a lower right longitudinal beam plate 252. The front ends of the upper right longitudinal beam plate 251 and the lower right longitudinal beam plate 252 are connected to the upper and lower surfaces of the seat crossbeam 21, respectively. The docking connection structure of the left longitudinal beam 24, the right longitudinal beam 25, and the seat crossbeam 21 constitutes the core force-bearing node at the front of the floor closed loop structure 20. Bending and bump loads are distributed between the left and right sides of the vehicle body here, ensuring balanced force distribution between the left and right sides.

[0041] Furthermore, the floor closed-loop structure 20 also includes a left sill rear connecting plate 26 and a right sill rear connecting plate 27. The left sill rear connecting plate 26 is connected to the front side of the left longitudinal beam 24 and the left end of the seat crossbeam 21, respectively. The right sill rear connecting plate 27 is connected to the front side of the right longitudinal beam 25 and the right end of the seat crossbeam 21, respectively. The sill rear connecting plates further strengthen the joint strength between the front end of the longitudinal beam and the seat crossbeam 21, simplify the assembly and welding process, and reduce the difficulty of production and manufacturing costs.

[0042] Regarding the reinforcement of the rear closure node of the floor closed loop structure 20: such as Figure 4 and Figure 5 As shown, the rear end of the left longitudinal beam 24 is provided with a left longitudinal beam connecting plate 243 that closes its rear end face, and is connected to the rear bulkhead 13 through the left longitudinal beam connecting plate 243. The rear end of the right longitudinal beam 25 is provided with a right longitudinal beam connecting plate 253 that closes its rear end face, and is connected to the rear bulkhead 13 through the right longitudinal beam connecting plate 253. The connection structure of the left longitudinal beam 24, the right longitudinal beam 25 and the rear bulkhead 13 constitutes the rear closed node of the floor closed loop structure 20, which constrains the deformation of the rear of the vehicle body, improves the vehicle's resistance to compression and rear-end collision deformation, and at the same time realizes the smooth transfer of load from the longitudinal beams to the rear bulkhead.

[0043] This application also provides a vehicle comprising a dual-closed-loop body structure 100 for a two-seater vehicle as described in any of the above embodiments. This vehicle is a two-seater and possesses all the advantages of the aforementioned body structure, including high rigidity, lightweight, high collision safety, and excellent manufacturability.

[0044] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in this application, and these should all be included within the scope of protection of this application.

Claims

1. A double-closed-loop body structure (100) for a two-seat vehicle, characterized in that, include: The passenger compartment closed loop structure (10) includes a rear crossbeam (11), a left C-pillar (12), a rear enclosure (13), and a right C-pillar (14). The rear crossbeam (11), the left C-pillar (12), the rear enclosure (13), and the right C-pillar (14) are connected end to end in sequence to form the passenger compartment closed loop structure (10). Floor closed ring structure (20), the floor closed ring structure (20) includes seat crossbeam (21), C-ring crossbeam (22), rear crossbeam (23), left longitudinal beam (24) and right longitudinal beam (25). The seat crossbeam (21), the C-ring crossbeam (22) and the rear crossbeam (23) are arranged sequentially from front to back in the length direction of the vehicle body and are connected to the left longitudinal beam (24) and the right longitudinal beam (25) to form the floor closed ring structure (20). The crew cabin closed loop structure (10) and the floor closed loop structure (20) are rigidly connected to form a double closed loop load-bearing system.

2. The upper and lower double closed-loop body structure (100) of a two-seat vehicle according to claim 1, characterized in that, The rear end of the left longitudinal beam (24) is provided with a left longitudinal beam connecting plate (243) that closes its rear end face, and is connected to the rear enclosure (13) through the left longitudinal beam connecting plate (243). The rear end of the right longitudinal beam (25) is provided with a right longitudinal beam connecting plate (253) that closes its rear end face, and is connected to the rear enclosure (13) through the right longitudinal beam connecting plate (253).

3. The upper and lower double closed-loop body structure (100) of a two-seat vehicle according to claim 1, characterized in that, It also includes a left rear wheel cover (30) and a right rear wheel cover (40). The left C-pillar (12), the left end of the C-ring beam (22) and the left longitudinal beam (24) are connected by the left rear wheel cover (30). The right C-pillar (14), the right end of the C-ring beam (22) and the right longitudinal beam (25) are connected by the right rear wheel cover (40).

4. The upper and lower double closed-loop body structure (100) of a two-seat vehicle according to claim 3, characterized in that, The left C-pillar (12) includes a left C-pillar inner plate and a left C-pillar outer plate (121) connected together. The left C-pillar inner plate is connected to the left end of the C-ring crossbeam (22) and the left longitudinal beam (24) through the left rear wheel cover (30). The right C-pillar (14) includes a right C-pillar inner plate (141) and a right C-pillar outer plate (142) connected together. The right C-pillar inner plate (141) is connected to the right end of the C-ring crossbeam (22) and the right longitudinal beam (25) through the right rear wheel cover (40).

5. The upper and lower double closed-loop body structure (100) of a two-seat vehicle according to claim 1, characterized in that, It also includes a rear floor (50), the edges of which are connected to the rear surround (13), the seat crossbeam (21), the left longitudinal beam (24) and the right longitudinal beam (25), respectively, and the surface of the rear floor (50) is connected to the C-ring crossbeam (22) and the rear crossbeam (23).

6. The upper and lower double closed-loop body structure (100) of a two-seat vehicle according to claim 5, characterized in that, The C-ring beam (22) is connected to the upper surface of the left longitudinal beam (24), the upper surface of the rear floor (50), and the upper surface of the right longitudinal beam (25), respectively.

7. The upper and lower double closed-loop body structure (100) of a two-seat vehicle according to claim 5, characterized in that, The rear crossbeam (23) includes an upper rear crossbeam plate (231) and a lower rear crossbeam plate (232). The upper rear crossbeam plate (231) and the lower rear crossbeam plate (232) are arranged opposite each other along the vehicle height direction. The upper rear crossbeam plate (231) is connected to the upper surface of the rear floor (50), and the lower rear crossbeam plate (232) is connected to the lower surface of the rear floor (50). Both ends of the upper rear crossbeam plate (231) and the lower rear crossbeam plate (232) are respectively connected to the left longitudinal beam (24) and the right longitudinal beam (25).

8. The upper and lower double closed-loop body structure (100) of a two-seat vehicle according to claim 1, characterized in that, The left longitudinal beam (24) includes a left longitudinal beam upper plate (241) and a left longitudinal beam lower plate (242) connected together. The front end of the left longitudinal beam upper plate (241) and the front end of the left longitudinal beam lower plate (242) are respectively connected to the upper surface and the lower surface of the seat crossbeam (21); the right longitudinal beam (25) includes a right longitudinal beam upper plate (251) and a right longitudinal beam lower plate (252) connected together. The front end of the right longitudinal beam upper plate (251) and the front end of the right longitudinal beam lower plate (252) are respectively connected to the upper surface and the lower surface of the seat crossbeam (21).

9. The upper and lower double closed-loop body structure (100) of a two-seat vehicle according to claim 1, characterized in that, The floor closed loop structure (20) also includes a left sill rear connecting plate (26) and a right sill rear connecting plate (27). The left sill rear connecting plate (26) is connected to the front side of the left longitudinal beam (24) and the left end of the seat crossbeam (21), respectively. The right sill rear connecting plate (27) is connected to the front side of the right longitudinal beam (25) and the right end of the seat crossbeam (21), respectively.

10. A vehicle, characterized in that, Includes the upper and lower double closed-loop body structure (100) of a two-seat vehicle as described in any one of claims 1-9.

Images