A steel body for a pure electric vehicle

Abstract

The present invention relates to the technical field of electric vehicles, and provides a steel body for a pure electric vehicle. The front floor assembly includes a pair of front floor longitudinal beams; the front floor longitudinal beams have a bent section that is bent from the lapping edge towards the sill beam and a straight section that is arranged parallel to the sill beam; a pair of first fixing points fixedly connected to the power battery are provided on the front floor longitudinal beams, and the first fixing points are located on the bent section of the front floor longitudinal beams. The steel body for a pure electric vehicle provided by the present invention adopts a steel body, which reduces the manufacturing cost and processing difficulty; the front floor longitudinal beams in the front floor assembly are bent towards the sill beam, thereby avoiding the interference problem between the front floor longitudinal beams and the power battery. At the same time, a pair of first fixing points are arranged at the front end of the power battery, effectively utilizing the structural stiffness of the power battery to improve the anti-bending performance of the bent section of the front floor longitudinal beams and improving the vehicle collision safety performance.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicles, and particularly to a steel body for a pure electric vehicle. Background Art

[0002] With the continuous development of technology, electric vehicles, as a type of new energy vehicle, have also developed rapidly along with the trend of green environmental protection. Due to the significant differences in the powertrains between electric vehicles and traditional fuel vehicles, the body of an electric vehicle needs to make significant adaptive changes according to the different powertrains. Aluminum bodies have emerged as a result. However, the processing cost of aluminum bodies is too high and the processing technology is not yet mature enough, resulting in a standstill in the development of aluminum bodies for electric vehicles. Based on the disadvantages of pure aluminum bodies, steel-aluminum hybrid bodies have also become a current research and development hotspot. However, the manufacturing cost and connection technology of steel-aluminum hybrid bodies are also problems that need to be urgently solved.

[0003] When the steel body of a traditional fuel vehicle is applied to an electric vehicle, there are also some problems. One is the problem that a large power battery seriously interferes with the floor longitudinal beam and cannot be installed. The other is the problem that a small power battery results in insufficient battery range.

[0004] In the publicly disclosed patent CN107140026A, a structure of the longitudinal and transverse beams of the lower body of an electric vehicle is provided. For the layout of the power battery, the floor longitudinal beam structure is cancelled in this structure, thus reducing the main force transmission path in a frontal collision. In this application, in order to meet the collision performance in a high-speed collision, the lap strength of the transverse and longitudinal beams is increased and more and stronger cross beams are added to transmit the collision force. Although such a design solves the interference problem between the floor longitudinal beam and the power battery, it also greatly increases the design difficulty of the body structure, the weight of the body, and the processing cost. Summary of the Invention

[0005] The purpose of the present invention is to solve the disadvantages that the processing cost and difficulty of using an aluminum body in existing electric vehicles are relatively large, and when using a traditional steel body, the floor longitudinal beam seriously interferes with the power battery and a small power battery needs to be selected, resulting in insufficient battery range, and to provide a steel body for a pure electric vehicle.

[0006] The technical solution adopted by the present invention to solve its technical problems is as follows: A steel body for a pure electric vehicle, including a front body assembly, a front floor assembly, and a rear floor assembly arranged in sequence from front to rear. The front body assembly includes a pair of front longitudinal beams, a front bulkhead cross beam, and a pair of sill beams. The rear floor assembly includes a pair of rear floor longitudinal beams and a rear floor cross beam arranged between the pair of rear floor longitudinal beams. The front floor assembly includes a pair of front floor longitudinal beams. The front ends of the pair of front floor longitudinal beams overlap with the pair of front longitudinal beams on the front bulkhead cross beam and form two overlapping edges. The rear ends of the pair of front floor longitudinal beams overlap with the pair of rear floor longitudinal beams on the rear floor cross beam. The front floor longitudinal beam has a bent section bent from the overlapping edge towards the sill beam and a straight section arranged parallel to the sill beam. A space for placing a power battery is provided on the front floor assembly and the rear floor assembly. A pair of first fixing points fixedly connected to the power battery are provided on the front floor longitudinal beam, and the first fixing points are located on the bent section of the front floor longitudinal beam.

[0007] Further, at least two pairs of second fixing points fixedly connected to the power battery are further provided on the front floor longitudinal beam, and the second fixing points are located on the straight section of the front floor longitudinal beam.

[0008] Further, the front floor longitudinal beam includes a front floor longitudinal beam body having a bent section and a straight section, a cover plate arranged on the front floor longitudinal beam body, and a reinforcing member located inside the front floor longitudinal beam body.

[0009] Specifically, the cover plate is located on the bent section, and the reinforcing member is located on the bent section and extends to the middle of the straight section.

[0010] Further, the front floor assembly further includes a front floor cross beam fixedly connected between the bent sections of the two front floor longitudinal beams.

[0011] Specifically, the front body assembly further includes a pair of A-pillars located on both sides of the front bulkhead cross beam and used to connect the front bulkhead cross beam with the pair of sill beams. The front floor assembly further includes a pair of front floor cross beam reinforcing members, and the front floor cross beam reinforcing members are located on the bent sections of the front floor longitudinal beams to fixedly connect the front floor cross beam with the A-pillars.

[0012] Specifically, the front floor assembly further includes two front seat mounting cross beams spanning between the pair of front floor longitudinal beams, and both ends of the two front seat mounting cross beams are fixed to the straight sections of the front floor longitudinal beams.

[0013] Specifically, the front floor assembly further includes a front floor body and a middle channel fixed above the front floor body. The middle channel includes a first connection section fixedly connected to the front bulkhead crossbeam, a second connection section fixedly connected to the front floor crossbeam, a third connection section fixedly connected to two front seat mounting crossbeams, and a fourth connection section fixedly connected to the rear floor crossbeam, which are arranged in sequence.

[0014] Specifically, the height of the middle channel gradually decreases from the first connection section to the fourth connection section, and the fourth connection section is arranged in a flat plate shape above the front floor body.

[0015] Furthermore, the front floor assembly further includes a side reinforcement fixed between the front floor longitudinal beam and the sill beam.

[0016] The beneficial effects of the steel body of the pure electric vehicle provided by the present invention are as follows: The whole vehicle adopts a steel body. On the premise of meeting the collision performance, the manufacturing cost and processing difficulty are greatly reduced compared with the aluminum body. The front floor longitudinal beam in the front floor assembly bends towards the sill beam, thus avoiding the interference problem between the front floor longitudinal beam and the power battery. At the same time, a pair of first fixing points are arranged at the front end of the power battery, and the first fixing points are located on the bending section of the front floor longitudinal beam. By connecting the first fixing points with the front power assembly, the power battery is incorporated into the longitudinal force transmission channel of the vehicle body. In this way, the structural stiffness of the power battery can be effectively utilized to improve the anti-bending performance of the bending section of the front floor longitudinal beam, thereby solving the problem of insufficient collision force conduction in the bending section of the front floor longitudinal beam and improving the collision safety performance of the whole vehicle. Description of the Drawings

[0017] Figure 1 is a three-dimensional structural schematic diagram of a steel body of a pure electric vehicle provided by the present invention (excluding the front floor body);

[0018] Figure 2 is a top view of a steel body of a pure electric vehicle provided by the present invention;

[0019] Figure 3 is Figure 2 a cross-sectional view taken along line A-A in

[0020] Figure 4 is a bottom view of a steel body of a pure electric vehicle provided by the present invention;

[0021] Figure 5 is Figure 4 a cross-sectional view taken along line B-B in

[0022] Figure 6 is a side view of the front floor longitudinal beam of a steel body of a pure electric vehicle provided by the present invention;

[0023] Figure 7 is Figure 6 A cross-sectional view at the C-C position;

[0024] Figure 8 is a partial top view of the front floor longitudinal beam of a steel body of a pure electric vehicle provided by the present invention;

[0025] Figure 9 is a side view of the middle channel of a steel body of a pure electric vehicle provided by the present invention;

[0026] Figure 10 is a three-dimensional structural schematic diagram of the front floor cross beam and the front floor cross beam reinforcement of a steel body of a pure electric vehicle provided by the present invention;

[0027] Figure 11 is a three-dimensional structural schematic diagram of the side reinforcement of a steel body of a pure electric vehicle provided by the present invention;

[0028] Figure 12 is a bottom view of a steel body of a pure electric vehicle with a power battery installed provided by the present invention.

[0029] In the figure: 100 - steel body structure of a pure electric vehicle;

[0030] 10 - front body assembly, 11 - front longitudinal beam, 12 - front bulkhead cross beam, 13 - A-pillar, 14 - sill beam;

[0031] 20 - front floor assembly, 21 - front floor longitudinal beam, 211 - overlapping edge, 212 - bending section, 213 - straight section, 214 - front floor longitudinal beam body, 215 - cover plate, 216 - reinforcement, 22 - front floor body, 23 - middle channel, 231 - first connection section, 232 - second connection section, 233 - third connection section, 234 - fourth connection section, 24 - front floor cross beam, 25 - front floor cross beam reinforcement, 26 - front seat mounting cross beam, 27 - side reinforcement;

[0032] 30 - rear floor assembly, 31 - rear floor longitudinal beam, 32 - rear floor cross beam;

[0033] 40 - power battery, 41 - first fixing point, 42 - second fixing point. Detailed implementation manners

[0034] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to 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.

[0035] See Figures 1-12, a steel body 100 for a pure electric vehicle provided by the present invention, includes a front body assembly 10, a front floor assembly 20, and a rear floor assembly 30 arranged in sequence from front to rear. In the entire vehicle body, the front body assembly 10, the front floor assembly 20, and the rear floor assembly 30 are all made of steel structures. Creative improvements are made to the installation of the power assembly on the traditional steel vehicle body, enabling it to accommodate power batteries of larger sizes. The steel body 100 for a pure electric vehicle provided by the present invention greatly reduces the processing cost compared with the existing pure electric aluminum body, and tries to use the original components that can be used in traditional fuel vehicles as much as possible, reducing the input cost of new products in vehicle body development. Compared with the current steel-aluminum hybrid body, it also reduces the processing difficulty. Moreover, the steel body 100 can greatly improve the collision performance of the whole vehicle and enhance the safety performance of pure electric vehicles.

[0036] Specifically, as Figure 1 shown, the front body assembly 10 in the pure electric steel body 100 includes a pair of front longitudinal beams 11, a front bulkhead cross beam 12, a pair of A-pillars 13, and a pair of sill beams 14. A pair of A-pillars 13 are located on both sides of the front bulkhead cross beam 12 and are used to connect the front bulkhead cross beam 12 with a pair of sill beams 14. The rear floor assembly 30 includes a pair of rear floor longitudinal beams 31 and a rear floor cross beam 32 arranged between the pair of rear floor longitudinal beams 31. The front floor assembly 20 is connected between the front body assembly 10 and the rear floor assembly 30, and solves the problem that the front floor assembly 20 of a traditional fuel vehicle interferes with the power battery 40, resulting in the inability to place a large power battery pack.

[0037] Furthermore, as Figure 2 and Figure 3 shown, the front floor assembly 20 includes a pair of front floor longitudinal beams 21, a front floor body 22, and a middle channel 23 fixed above the front floor body 22; the front ends of the pair of front floor longitudinal beams 21 overlap with the pair of front longitudinal beams 11 on the front bulkhead cross beam 12 and form two overlapping edges 211, and the rear ends of the pair of front floor longitudinal beams 21 overlap with the pair of rear floor longitudinal beams 31 on the rear floor cross beam 32. As Figure 6As shown in the figure, the front floor longitudinal beam 21 provided by the present invention has a bending section 212 bent from the overlapping edge 211 towards the sill beam 14 and a straight section 213 arranged parallel to the sill beam 14. The front floor longitudinal beam 21 on the front floor assembly 20 starts to bend towards both sides and the bottom of the vehicle body at one end close to the front body assembly 10, that is, at the overlapping edge 211 of the front bulkhead cross beam 12, and the straight section 213 of the front floor longitudinal beam 21 directly extends to the inner side of the sill beam 14, maximizing the relative position between a pair of front floor longitudinal beams 21, thereby increasing the placement space for the battery pack, so that the steel vehicle body 100 can accommodate a large power battery 40. In the pure electric steel vehicle body 100 provided in this embodiment, a power battery 40 with a length of 1900 mm and a width of 1060 mm can be arranged, enabling the pure electric vehicle to have a cruising range of more than 500 KM.

[0038] As Figure 4 and Figure 12 shown, in the bottom space of the front floor assembly 20 and the rear floor assembly 30, there is a space for placing the power battery 40. Since the front floor longitudinal beam 21 in the front floor assembly 20 bends towards both sides, the internal width of the front floor assembly 20 is increased, thus solving the problem of interference between the front floor longitudinal beam 21 and the power battery 40. At the same time, a pair of first fixing points 41 fixedly connected to the power battery 40 are provided on the front floor longitudinal beam 21, and the first fixing points 41 are located at the bending section 212 of the front floor longitudinal beam 21. Since the front floor longitudinal beam 21 has a large-angle offset in the direction from its overlapping edge 211 towards the sill beam 14, the larger the offset angle, the more likely it is to cause the problem of poor longitudinal force transmission in the bending section 212 of the front floor longitudinal beam 21. Therefore, in the present invention, a pair of first fixing points 41 for connecting with the power battery 40 are provided on the bending section 212 of the front floor longitudinal beam 21, and the collision force is effectively transmitted and dispersed through the first fixing points 41. Moreover, the first fixing points 41 make full use of the structural stiffness of the power battery 40 to make up for the problem of poor force transmission in the bending section 212 area of the front floor longitudinal beam 21, indirectly increasing the overall stiffness of the front floor longitudinal beam 21. Even when subjected to a violent impact, the bending section 212 will not bend and deform.

[0039] Furthermore, as Figure 4 and Figure 12As shown, at least two pairs of second fixing points 42 for fixedly connecting with the power battery 40 are further provided on the front floor longitudinal beam 21, and the second fixing points 42 are located on the straight section 213 of the front floor longitudinal beam 21. In this embodiment, eight second fixing points 42 are evenly distributed on the pair of front floor longitudinal beams 21, and the eight second fixing points 42 are used to stably fix the power battery 40 inside the front floor assembly 20 and the rear floor assembly 30, ensuring the connection stability between the power battery 40 and the front floor assembly 20 and the rear floor assembly 30.

[0040] Further, in this embodiment, as Figure 7 shown, in order to ensure the overall stiffness and strength of the front floor longitudinal beam 21 in the front floor assembly 20, the front floor longitudinal beam 21 includes a front floor longitudinal beam body 214 having a bending section 212 and a straight section 213, a cover plate 215 provided on the front floor longitudinal beam body 214, and a reinforcing member 216 located inside the front floor longitudinal beam body 214. Both the cover plate 215 and the reinforcing member 216 are provided to improve the overall strength of the front floor longitudinal beam body 214. The front floor longitudinal beam body 214 is a bent member with a U-shaped opening facing upward, the cover plate 215 is provided above the front floor longitudinal beam body 214 and at the opening, and the cover plate 215 is connected to the front floor longitudinal beam body 214 by curved surface matching welding. The reinforcing member 216 in the front floor longitudinal beam 21 is fixed inside the U-shaped bent member of the front floor longitudinal beam body 214 by welding.

[0041] Specifically, as Figure 8 shown, the cover plate 215 in the front floor longitudinal beam 21 is located at the bending section 212, and the reinforcing member 216 is located at the bending section 212 and extends to the middle of the straight section 213. The cover plate 215 is provided in the area of the bending section 212 between the front panel cross beam 12 and the sill beam 14, mainly to ensure the stiffness and strength of the front floor longitudinal beam 21 at its large bending offset. And the reinforcing member 216 also extends from the front panel cross beam 12 to the middle of the straight section 213. The setting of the reinforcing member 216 can not only improve the strength and stiffness of the bending section 212 of the front floor longitudinal beam 21, but also improve the rigidity of the straight section 212 of the front floor longitudinal beam 21, thereby improving the collision performance of the front floor longitudinal beam 21 during a column collision.

[0042] Further, as Figure 1 and Figure 10 shown, the front floor assembly 20 further includes a front floor cross beam 24 fixedly connected between the bending sections 212 of the two front floor longitudinal beams 21. The front floor cross beam 24 is used to improve the force transmission and dispersion of the pair of front floor longitudinal beams 21, and can laterally transmit the longitudinal collision force through the front floor cross beam 24. The front floor cross beam 24 has an intermediate section 241 and connecting sections 242 respectively connected to the pair of front floor longitudinal beams 21 on both sides.

[0043] Specifically, Figure 5 As shown, the front floor assembly 20 further includes a pair of front floor cross beam reinforcements 25, which are located at the curved section 212 of the front floor longitudinal beam 21 to fixedly connect the front floor cross beam 24 with the A-pillar 13. On the one hand, the front floor cross beam reinforcement 25 connects the front floor longitudinal beam 21 with the A-pillar 13. In the process of a frontal collision of the vehicle, the front floor longitudinal beam 21 bears most of the collision force from the front longitudinal beam 11 and the collision force from the subframe, and is the main channel for longitudinal force transmission. The front floor longitudinal beam 21 disperses the collision force to the A-pillar 13 and the door sill beam 14 through the front floor cross beam reinforcement 25, effectively transmitting and dispersing the collision force. On the other hand, the front floor cross beam reinforcement 25 can connect the front floor cross beam 24 with the A-pillar 13, thereby dispersing the longitudinal collision force to the middle channel 23 through the front floor cross beam 24, further dispersing and transmitting the collision force.

[0044] Furthermore, if Figure 2 As shown, the front floor assembly 20 provided by the present invention further includes two front seat mounting cross beams 26 spanning between a pair of front floor longitudinal beams 21, and both ends of the two front seat mounting cross beams 26 are fixed to the straight section 213 of the front floor longitudinal beams 21. The front seat mounting cross beams 26 are arranged above the front floor body 22, and the middle channel 23 is vertically arranged on the two front seat mounting cross beams 26.

[0045] like Figure 1 , Figure 2 as well as Figure 9 Therefore, the front floor assembly 20 provided by the present invention also includes a front floor body 22 and a middle channel 23 fixed above the front floor body 22, and the middle channel 23 includes a first connecting section 231 fixedly connected to the front dash panel cross beam 12, a second connecting section 232 fixedly connected to the front floor cross beam 24, a third connecting section 233 fixedly connected to the two front seat mounting cross beams 26, and a fourth connecting section 234 fixedly connected to the rear floor cross beam 32, which are arranged in sequence. The middle channel 23 is formed above the front floor body 22 and is located on the longitudinal center axis of the front floor body 22. The front end of the middle channel 23 is tilted and fixed to the front dash panel cross beam 12, and the rear end is fixed to the rear floor cross beam 32 in a flat plate shape, and the middle part from the front floor cross beam 24 to the two front seat mounting cross beams 26 is tightly attached to the front floor body 22. Figure 3 and Figure 5 It can be clearly seen from the comparison that the height of the middle channel 23 is gradually reduced, thereby increasing the space inside the passenger compartment.

[0046] Specifically, Figure 1As shown in the figure, a pure electric steel body 100 provided by the present invention is applicable to pure electric vehicles. Therefore, there is no need to set up an exhaust system for traditional fuel vehicles in the middle channel 23. Therefore, on the premise of ensuring the connection stiffness and strength, the overall height of the middle channel 23 can be reduced as much as possible. The height of the middle channel 23 gradually decreases from the first connection section 231 to the fourth connection section 234. The fourth connection section 234 is arranged in a flat plate shape above the front floor body 22. The height of the fourth connection section 234 is reduced to the minimum to the greatest extent, thereby increasing the space at the rear seat aisle in the passenger compartment and improving the comfort at the middle position of the rear seat in the passenger compartment.

[0047] Furthermore, as Figure 4 shown, the front floor assembly 20 provided by the present invention further includes a side reinforcement 27 fixed between the front floor longitudinal beam 21 and the sill beam 14. The side reinforcement 27 is arranged in the straight section 213 area of the front floor longitudinal beam 21 and has a plurality of side reinforcements 27 for improving the stability between the front floor longitudinal beam 21 and the sill beam 14 and enhancing the collision performance of column collision. As Figure 11 shown, the side reinforcement 27 has a reinforcement body 271 arranged between the sill beam 14 and the front floor longitudinal beam 21, a first welding end 272 connected to the sill beam 14, and a second welding end 273 connected to the front floor longitudinal beam 21. The first welding end 272 and the second welding end 273 are both fixed by spot welding.

[0048] Furthermore, as Figure 1 and Figure 2 shown, when a pure electric vehicle steel body 100 provided by the present invention undergoes a frontal collision, the force is transmitted and dispersed through the following paths. Specifically, the force transmission channels are as follows:

[0049] The first longitudinal force transmission channel: front longitudinal beam 11 - front floor longitudinal beam 21 - first fixing point 41 - power battery 40 - second fixing point 42;

[0050] The second longitudinal force transmission channel: front longitudinal beam 11 - front floor longitudinal beam 21 - front floor cross beam reinforcement 25 - A-pillar 13 - sill beam 14;

[0051] The third longitudinal force transmission channel: front longitudinal beam 11 - front panel cross beam 12 - middle channel 23; front longitudinal beam 11 - front panel cross beam 12 - A-pillar 13 - sill beam 14;

[0052] The fourth longitudinal force transmission channel: front longitudinal beam 11 - front floor longitudinal beam 21 - front floor cross beam 24 - middle channel 23;

[0053] The first transverse force transmission channel: front longitudinal beam 11 - front panel cross beam 12 - A-pillar 13;

[0054] The second transverse force transmission channel: front longitudinal beam 11 - front floor longitudinal beam 21 - front floor cross beam 24 - front floor cross beam reinforcement 25 - A-pillar 13;

[0055] The third transverse force transmission channel: front longitudinal beam 11 - front floor longitudinal beam 21 - side reinforcement 27 - sill beam 14.

[0056] Through the above longitudinal force transmission channels and transverse force transmission channels, the frontal collision force can be transmitted to various components at the rear of the vehicle body. In particular, for the first longitudinal force transmission channel, the second longitudinal force transmission channel, and the fourth longitudinal force transmission channel, the front floor longitudinal beam 21 is required for force transmission. Therefore, the strength and stiffness of the front floor longitudinal beam 21 will directly affect the safety performance of the vehicle. In the front floor assembly 20 provided by the present invention, a bending section 212 is provided on the front floor longitudinal beam 21 for placing the power battery 40. The setting of the bending section 212 expands the width between the front floor longitudinal beams 21, and a larger-capacity power battery 40 can be arranged. At the same time, the bending section 212 is connected to the power battery 40 through a first fixing point 41, and the structural stiffness of the power battery 40 is fully utilized to make up for the problem of poor force transmission in the bending area. At the same time, the front floor cross beam 24 and the front floor cross beam reinforcement 25 provided on the bending section 212 can both transmit the force received on the front floor longitudinal beam 21 laterally to the side A-pillar 13 and sill beam 14, improving the overall vehicle collision safety performance. Moreover, the height of the middle channel 23 in the front floor assembly 20 is reduced, greatly improving the space in the passenger compartment and the comfort of the occupants.

[0057] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A steel body for a pure electric vehicle, comprising a front body assembly, a front floor assembly, and a rear floor assembly arranged in sequence from front to rear. The front body assembly includes a pair of front longitudinal beams, a front bulkhead cross beam, and a pair of sill beams. The front floor assembly includes a pair of front floor longitudinal beams. The rear floor assembly includes a pair of rear floor longitudinal beams and a rear floor cross beam disposed between the pair of rear floor longitudinal beams. Characterized in that: The front ends of a pair of the front floor longitudinal beams overlap with a pair of the front longitudinal beams on the front bulkhead cross beam and form two overlapping edges. The rear ends of a pair of the front floor longitudinal beams overlap with a pair of the rear floor longitudinal beams on the rear floor cross beam. The front floor longitudinal beam has a bent section bent from the overlapping edge towards the sill beam and a straight section arranged parallel to the sill beam. Spaces for placing power batteries are provided on the front floor assembly and the rear floor assembly. A pair of first fixing points fixedly connected to the power battery are provided on the front floor longitudinal beam, and the first fixing points are located at the bent section of the front floor longitudinal beam. At least two pairs of second fixing points fixedly connected to the power battery are further provided on the front floor longitudinal beam, and the second fixing points are located at the straight section of the front floor longitudinal beam. The front floor assembly further includes a front floor cross beam fixedly connected between the bent sections of the two front floor longitudinal beams.

2. A steel body for a pure electric vehicle according to claim 1, Characterized in that, The front floor longitudinal beam includes a front floor longitudinal beam body having a bent section and a straight section, a cover plate disposed on the front floor longitudinal beam body, and a reinforcing member located inside the front floor longitudinal beam body.

3. A steel body for a pure electric vehicle according to claim 2, Characterized in that, The cover plate is located at the bent section, and the reinforcing member is located at the bent section and extends to the middle of the straight section.

4. A steel body for a pure electric vehicle according to claim 1, Characterized in that, The front body assembly further includes a pair of A-pillars located on both sides of the front bulkhead cross beam and used for connecting the front bulkhead cross beam with a pair of sill beams. The front floor assembly further includes a pair of front floor cross beam reinforcing members, and the front floor cross beam reinforcing members are located at the bent section of the front floor longitudinal beam to fixedly connect the front floor cross beam with the A-pillar.

5. A steel body for a pure electric vehicle according to claim 1, Characterized in that, The front floor assembly further includes two front seat mounting cross beams spanning between a pair of the front floor longitudinal beams, and both ends of the two front seat mounting cross beams are fixed to the straight section of the front floor longitudinal beam.

6. A steel body for a pure electric vehicle according to claim 5, Characterized in that, The front floor assembly further includes a front floor body and a middle channel fixed above the front floor body. The middle channel includes a first connection section fixedly connected to the front bulkhead cross beam, a second connection section fixedly connected to the front floor cross beam, a third connection section fixedly connected to the two front seat mounting cross beams, and a fourth connection section fixedly connected to the rear floor cross beam arranged in sequence.

7. A steel body for a pure electric vehicle according to claim 6, Characterized in that, The height of the middle channel gradually decreases from the first connecting section to the fourth connecting section, and the fourth connecting section is arranged in a flat plate shape above the front floor body.

8. A steel body for a pure electric vehicle according to any one of claims 1-7, characterized in that the front floor assembly further includes a side reinforcing member fixed between the front floor longitudinal beam and the sill beam.

Images