CN212637688U

CN212637688U - Lower vehicle body frame structure

Info

Publication number: CN212637688U
Application number: CN202020538858.4U
Authority: CN
Inventors: 杨宏; 林佳武; 邱志勇
Original assignee: Guangzhou Automobile Group Co Ltd
Current assignee: Guangzhou Automobile Group Co Ltd
Priority date: 2020-04-13
Filing date: 2020-04-13
Publication date: 2021-03-02
Anticipated expiration: 2030-04-13

Abstract

The utility model relates to the technical field of vehicle body frames, and discloses a lower vehicle body frame structure, which comprises an engine compartment frame, a front floor frame and a rear floor frame which are connected in sequence; the engine compartment frame comprises front longitudinal beams and front longitudinal beam joints, the front floor frame comprises threshold beams, the rear floor frame comprises rear longitudinal beams and rear longitudinal beam joints, and transverse beam bodies and/or longitudinal beam bodies are arranged between the two front longitudinal beams, between the two front longitudinal beam joints, between the two threshold beams, between the two rear longitudinal beam joints and between the two rear longitudinal beams; each beam body is an extrusion part with a cross section of a closed structure, when the frame structure of the lower vehicle body needs to be expanded, the size of each beam body is changed according to the proportion, the length and the width of each corresponding frame are changed, the overall size of the frame of the lower vehicle body is changed, the components of the vehicle body of the lower vehicle body do not need to be redesigned, the structural strength requirement is met, and the research and development investment cost and the development period can be greatly reduced.

Description

Lower vehicle body frame structure

Technical Field

The utility model relates to a body frame technical field especially relates to a body frame construction down.

Background

The lower automobile body of the existing electric automobile is generally formed by stamping steel plates, and all stamping parts are welded and assembled to form the lower automobile body according to a certain process sequence, but the existing steel plate stamping technology is complex in forming process and high in cost, the manufactured lower automobile body is large in size and not beneficial to the whole light weight of the automobile, the stamping parts are high in manufacturing, assembling and maintaining cost and not beneficial to reducing cost, and when the size of a frame structure of the lower automobile body needs to be expanded, the structural design needs to be carried out again, and a die is developed again to adapt to the lower automobile body with a new size, so that the research and development investment cost and the development period are increased.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is: how to realize the quick expansion of the lower vehicle body frame structure with different sizes and meet the structural strength requirement.

In order to solve the technical problem, the utility model provides a lower vehicle body frame structure, which comprises an engine compartment frame, a front floor frame and a rear floor frame which are connected in sequence from front to back;

the engine compartment frame comprises two front longitudinal beam assemblies extending along the longitudinal direction, each front longitudinal beam assembly comprises a front longitudinal beam and a front longitudinal beam joint, the front end of each front longitudinal beam joint is arranged at the rear end of the corresponding front longitudinal beam,

the front floor frame comprises two threshold beams extending along the longitudinal direction, the front ends of the threshold beams are correspondingly connected with the rear ends of the front longitudinal beam joints,

the rear floor frame comprises two rear longitudinal beam assemblies extending along the longitudinal direction, each rear longitudinal beam assembly comprises a rear longitudinal beam and a rear longitudinal beam joint, the rear end of each rear longitudinal beam joint is connected with the front end of the rear longitudinal beam, the front end of each rear longitudinal beam joint is connected with the rear end of each threshold beam in a one-to-one correspondence manner,

transverse beam bodies and/or longitudinal beam bodies are arranged between the two front longitudinal beams, between the two front longitudinal beam joints, between the two threshold beams, between the two rear longitudinal beam joints and between the two rear longitudinal beams;

the front longitudinal beam, the threshold beam, the rear longitudinal beam, the transverse beam body and the longitudinal beam body are extrusion parts with cross sections in a closed structure.

Preferably, the front longitudinal beam, the threshold beam, the rear longitudinal beam, each of the transverse beam bodies and each of the longitudinal beam bodies are aluminum alloy pieces.

Preferably, the front longitudinal beam joint and the rear longitudinal beam joint are both cast parts.

Preferably, the cross section of the front longitudinal beam is integrally vertical in a shape like a Chinese character ri.

As a preferred scheme, two transverse beam bodies are arranged between the two front longitudinal beams, and are respectively a front anti-collision beam and a front cross beam, two ends of the front anti-collision beam are respectively connected to the front end of one front longitudinal beam, and two ends of the front cross beam are respectively connected to the rear end of one front longitudinal beam;

and the transverse beam body is connected between the two front longitudinal beam joints and is a front wall lower cross beam.

As a preferred scheme, the cross section of the front anti-collision beam is in a vertical 'mu' shape, and the cross section of the front cross beam is in a 'square';

the cross section of the front wall lower cross beam is wholly trapezoidal, the front side wall of the front wall lower cross beam extends in the vertical direction and is limited to be one waist of the trapezoid, the lower side wall of the front wall lower cross beam extends in the transverse direction and is limited to be the other waist of the trapezoid, at least one first reinforcing plate extending in the transverse direction and at least one second reinforcing plate extending in the vertical direction are arranged in the inner cavity of the front wall lower cross beam, and therefore the inner cavity of the front wall lower cross beam is divided into a plurality of first reinforcing chambers.

Preferably, the cross section of the threshold beam is integrally rectangular, and an inner concave part is arranged at the joint of the lower side wall of the threshold beam and the outer side wall of the threshold beam;

at least one third reinforcing plate extending along the transverse direction and at least one fourth reinforcing plate extending along the vertical direction are arranged in the inner cavity of the threshold beam, so that the inner cavity of the threshold beam is divided into a plurality of second reinforcing chambers.

Preferably, two transverse beam bodies are arranged between the two threshold beams, the transverse beam bodies are seat cross beams, the two seat cross beams are distributed at intervals from front to back, two ends of each seat cross beam are respectively connected to the middle part of one threshold beam,

and the longitudinal beam body is arranged between the two threshold beams and is a middle channel, and the middle channel is sequentially connected with each seat cross beam.

Preferably, the cross section of the seat cross beam is in a transverse Chinese character 'ri' shape, the lower side wall of the seat cross beam extends to the front side and the rear side along the transverse direction respectively, and first extending portions are formed on the lower side wall and the front side and the rear side respectively;

the cross section of the middle channel is overall trapezoidal, the upper side wall and the lower side wall of the middle channel extend along the transverse direction and are respectively limited to be a bottom edge of the trapezoid, the lower side wall of the middle channel extends towards the left side and the right side along the transverse direction respectively and is provided with a second extending portion, at least one fifth reinforcing plate extending along the transverse direction and at least one sixth reinforcing plate extending along the vertical direction are arranged in the inner cavity of the middle channel, and therefore the inner cavity of the middle channel is divided into a plurality of third reinforcing chambers.

Preferably, the cross section of the rear longitudinal beam is integrally vertical in a shape like a Chinese character ri, the upper side wall of the rear longitudinal beam extends towards the left side and the right side along the transverse direction, and third extending portions are formed on the upper side wall and the right side wall.

As a preferred scheme, four transverse beam bodies are arranged between two rear longitudinal beam joints, which are respectively a first rear cross beam, a second rear cross beam, a third rear cross beam and a fourth rear cross beam, the first rear cross beam, the second rear cross beam, the third rear cross beam and the fourth rear cross beam are sequentially distributed at intervals from front to back, two ends of the first rear cross beam are respectively connected to the front end of one rear longitudinal beam joint, two ends of the fourth rear cross beam are respectively connected to the rear end of one rear longitudinal beam joint, two ends of the third rear cross beam and two ends of the fourth rear cross beam are respectively connected to the middle part of one rear longitudinal beam joint,

and a transverse beam body is arranged between the two rear longitudinal beams and is a rear anti-collision beam, and two ends of the rear anti-collision beam are respectively connected to the rear ends of the rear longitudinal beams.

As a preferred scheme, the cross section of the rear anti-collision beam is integrally vertical in a shape like a Chinese character ri;

the cross section of the first rear cross beam is integrally trapezoidal, the upper side wall and the lower side wall of the first rear cross beam extend along the transverse direction and are respectively limited to form two bottom edges of the trapezoid, and the lower side wall of the first rear cross beam extends towards the front side and the rear side along the transverse direction and is respectively provided with a fourth extending part;

the cross section of the second rear cross beam is integrally a parallelogram with the bottom inclined to the front side, the upper side wall and the lower side wall of the second rear cross beam extend transversely, the rear side of the upper side wall of the second rear cross beam extends backwards and upwards to form a fifth extension part, and the front side of the lower side wall of the second rear cross beam extends transversely and forwards to form a sixth extension part;

the cross section of the third rear cross beam is integrally in a shape like a Chinese character 'kou', a seventh extending portion is formed by extending the rear side of the upper side wall of the third rear cross beam backwards in the transverse direction, and an eighth extending portion is formed by extending the front side of the upper side wall of the third rear cross beam forwards and downwards.

The utility model provides a pair of lower vehicle body frame construction compares with prior art, and its beneficial effect lies in:

the utility model divides the lower vehicle body frame structure into an engine compartment frame, a front floor frame and a rear floor frame, when the lower vehicle body frame structure is required to be expanded, the front longitudinal beam, the threshold beam, the rear longitudinal beam, the transverse beam and the longitudinal beam are changed according to the proportion, the length and the width of each corresponding frame are changed to change the overall size of the lower vehicle body frame, because each frame component is an extrusion piece, the production and assembly can be directly carried out after the size is changed, the redesign of each component of the lower vehicle body is not required, thereby achieving the purpose of expanding the overall size of the lower vehicle body frame structure, and the front longitudinal beam, the threshold beam, the rear longitudinal beam, the transverse beam and the longitudinal beam are extrusion pieces with cross sections in closed structures, ensuring that the lower vehicle body is expanded or shortened in size, the requirement of structural strength can be met, and the research and development investment cost and the development period can be greatly reduced.

Drawings

Fig. 1 is a schematic view of the overall structure of a lower body frame structure according to a preferred embodiment of the present invention.

FIG. 2 is a cross-sectional view of the front rail taken along line A-A of FIG. 1.

Fig. 3 is a cross-sectional view of the front impact beam B-B of fig. 1.

FIG. 4 is a cross-sectional view of the front cross member of FIG. 1 at C-C.

FIG. 5 is a cross-sectional view of the cowl bottom rail of D-D of FIG. 1.

Fig. 6 is a cross-sectional view of the threshold beam of E-E in fig. 1.

Fig. 7 is a cross-sectional view of the seat beam F-F of fig. 1.

Fig. 8 is a schematic cross-sectional view of the center channel of G-G in fig. 1.

FIG. 9 is a cross-sectional view of the rear side rail of H-H of FIG. 1.

FIG. 10 is a cross-sectional view of the first rear cross member of FIG. 1 at I-I.

FIG. 11 is a cross-sectional view of the second rear cross member of J-J of FIG. 1.

FIG. 12 is a cross-sectional view of the third rear cross member taken along line K-K in FIG. 1.

Fig. 13 is a cross-sectional view of the rear impact beam L-L of fig. 1.

In the figure:

100. an engine compartment frame; 110. a front longitudinal beam; 120. a front rail joint; 130. a front impact beam; 140. front cross member; 150. a front wall lower beam; 151. a first reinforcing plate; 152. a second reinforcing plate; 153. a first reinforcement chamber;

200. a front floor frame; 210. a threshold beam; 211. an inner concave portion; 212. a third reinforcing plate; 213. a fourth reinforcing plate; 214. a second reinforcement chamber; 220. a seat cross member; 221. a first extension portion; 230. a middle channel; 231. a second epitaxial portion; 232. the fifth strengthening board; 233. a sixth reinforcing plate; 234. a third reinforcement chamber;

300. a rear floor frame; 310. a rear stringer; 311. a third extension portion; 320. a rear stringer joint; a first rear cross member 330; 331. a fourth epitaxial portion; 340. a second rear cross member; 341. a fifth extension portion; 342. a sixth extension; 350. a third rear cross member; 351. a seventh extension portion; 352. an eighth extension portion; 360. a fourth rear cross member; 370. and a rear anti-collision beam.

Detailed Description

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the terms "connected," "connected," and "fixed" used in the present invention should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral body; the connection can be mechanical connection or welding connection; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

As shown in fig. 1 to 13, the present invention according to the preferred embodiment provides a lower body frame structure, which includes an engine compartment frame 100, a front floor frame 200, and a rear floor frame 300, which are sequentially connected from front to rear;

the engine compartment frame 100 includes two longitudinally extending front side member assemblies, each of which includes a front side member 110 and a front side member joint 120, the front end of the front side member joint 120 is mounted to the rear end of the front side member 110,

the front floor frame 200 includes two threshold beams 210 extending in a longitudinal direction, a front end of each threshold beam 210 is connected to a rear end of each front side rail joint 120 in a one-to-one correspondence,

the rear floor frame 300 includes two rear longitudinal beam assemblies extending in the longitudinal direction, the rear longitudinal beam assemblies include rear longitudinal beams 310 and rear longitudinal beam joints 320 whose rear ends are connected to the front ends of the rear longitudinal beams 310, the front ends of the rear longitudinal beam joints 320 are connected to the rear ends of the threshold beams 210 in a one-to-one correspondence,

transverse beam bodies and/or longitudinal beam bodies are arranged between the two front longitudinal beams 110, between the two front longitudinal beam joints 120, between the two threshold beams 210, between the two rear longitudinal beam joints 320 and between the two rear longitudinal beams 310;

the front longitudinal beam 110, the threshold beam 210, the rear longitudinal beam 310, the transverse beam body and the longitudinal beam body are extruded parts with closed cross sections.

Based on the technical characteristics of the lower vehicle body frame structure, the lower vehicle body frame structure is divided into an engine compartment frame 100, a front floor frame 200 and a rear floor frame 300, when the lower vehicle body frame structure needs to be expanded, the length and width of each corresponding frame are changed by changing the size of the front longitudinal beam 110, the threshold beam 210, the rear longitudinal beam 310, each transverse beam and each longitudinal beam in the length direction in proportion, so that the overall size of the lower vehicle body frame is changed, because the components of each frame are extrusion parts, the production and assembly can be directly carried out after the size is changed, the components of the lower vehicle body are not required to be redesigned, so that the purpose of expanding the overall size of the lower vehicle body frame structure is achieved, and the front longitudinal beam 110, the threshold beam 210, the rear longitudinal beam 310, the transverse beam and the longitudinal beam are extrusion parts with cross sections in a closed structure, the automobile body of the lower automobile body can meet the structural strength requirement after being prolonged or shortened in size, and the research and development investment cost and the development period can be greatly reduced.

In this embodiment, the front longitudinal beam 110, the threshold beam 210, the rear longitudinal beam 310, the transverse beam bodies and the longitudinal beam bodies are all aluminum alloy members, so that the weight of the whole vehicle can be reduced, the corrosion resistance of the vehicle can be improved, and the cross section of the aluminum member is a closed cross section, so that the rigidity of the vehicle body can be effectively improved.

In this embodiment, the front side member joint 120 and the rear side member joint 320 are both cast members, and the front side member joint 120 and the rear side member joint 320 are used to be transitionally connected between frames to further reinforce, and the front side member joint 120 and the rear side member joint 320 are connected by riveting, FDS connection and structural adhesive to form a rigid connection structure, and are verified by CAE to meet the requirements of the overall rigidity, strength, collision and durability of the vehicle body.

In this embodiment, two transverse beam bodies are arranged between the two front longitudinal beams 110, the two transverse beam bodies are a front anti-collision beam 130 and a front cross beam 140, two ends of the front anti-collision beam 130 are connected to the front end of one front longitudinal beam 110 respectively, two ends of the front cross beam 140 are connected to the rear end of one front longitudinal beam 110 respectively, the profile of the combination of the front anti-collision beam 130 and the two front longitudinal beams 110 is U-shaped, so as to achieve an anti-collision effect, and the front cross beam 140 further reinforces the front longitudinal beams 110 on two sides; the transverse beam body is connected between the two front longitudinal beam joints 120 and is a front wall lower cross beam 150, and the front wall lower cross beam 150 further reinforces the front longitudinal beam joints 120 on two sides.

Wherein, as shown in fig. 2, the cross section of the front longitudinal beam 110 is generally vertical "ri" shape, as shown in fig. 3, the cross section of the front impact beam 130 is vertical "mu" shape, as shown in fig. 4, the cross section of the front cross beam 140 is "kou" shape, as shown in fig. 5, the cross section of the front lower cross beam 150 is generally trapezoidal, the front side wall of the front lower cross beam 150 extends vertically and defines a waist of the trapezoid, the lower side wall of the front lower cross beam 150 extends laterally and defines another waist of the trapezoid to achieve the fixed installation of the corresponding components, at least one first reinforcing plate 151 extending laterally and at least one second reinforcing plate 152 extending vertically are arranged in the inner cavity of the front lower cross beam 150 to divide the inner cavity of the front lower cross beam 150 into a plurality of first reinforcing chambers 153, so as to meet the requirements of the front longitudinal beam 110, the front impact beam 130, and the front impact beam 140, The front impact beam 130, the front cross member 140, and the front lower cross member 150 have internal strength requirements, which facilitate extension or reduction in size.

In this embodiment, two be equipped with two between threshold roof beam 210 the horizontal roof beam body, two the horizontal roof beam body is seat crossbeam 220, two seat crossbeam 220 is interval distribution from the past to the back, seat crossbeam 220's both ends are connected respectively in one the middle part of threshold roof beam 210, two still be equipped with one between threshold roof beam 210 vertical roof beam body, vertical roof beam body is well passageway 230, well passageway 230 connects gradually in each seat crossbeam 220, well passageway 230 with threshold roof beam 210 parallels, well passageway 230 is right seat crossbeam 220 plays further supporting role, the dispersion acts on pressure on seat crossbeam 220, further improves front floor frame 200's stability.

As shown in fig. 6, the cross-section of the threshold beam 210 is generally rectangular, an inner recess 211 is formed at a connection portion between a lower side wall of the threshold beam 210 and an outer side wall thereof, at least one third reinforcing plate 212 extending in a transverse direction and at least one fourth reinforcing plate 213 extending in a vertical direction are disposed in an inner cavity of the threshold beam 210, so as to divide the inner cavity of the threshold beam 210 into a plurality of second reinforcing chambers 214; as shown in fig. 7, the cross section of the seat cross member 220 is a transverse "japanese" shape, and the lower side wall of the seat cross member 220 extends to the front and rear sides along the transverse direction, and is formed with a first outer extension 221, so as to implement fixed installation of corresponding components; as shown in fig. 8, the cross section of the middle channel 230 is generally trapezoidal, the upper side wall and the lower side wall of the middle channel 230 extend in the transverse direction and respectively define a bottom side of the trapezoid, the lower side wall of the middle channel 230 extends in the transverse direction towards the left side and the right side, and both second extending portions 231 are formed to achieve fixed installation of corresponding components, at least one fifth reinforcing plate 232 extending in the transverse direction and at least one sixth reinforcing plate 233 extending in the vertical direction are arranged in the inner cavity of the middle channel 230 to divide the inner cavity of the middle channel 230 into a plurality of third reinforcing chambers 234, so as to meet the requirement of internal strength of the threshold beam 210, the seat cross beam 220 and the middle channel 230, and facilitate size extension or size reduction.

In this embodiment, four transverse beams are disposed between the two rear longitudinal beam joints 320, which are a first rear cross beam 330, a second rear cross beam 340, a third rear cross beam 350, and a fourth rear cross beam 360, the first rear cross member 330, the second rear cross member 340, the third rear cross member 350 and the fourth rear cross member 360 are sequentially distributed at intervals from front to back, both ends of the first rear cross member 330 are respectively connected to the front end of the rear longitudinal beam joint 320, both ends of the fourth rear cross member 360 are respectively connected to the rear end of one of the rear longitudinal beam joints 320, both ends of the third rear cross member 350 and both ends of the fourth rear cross member 360 are respectively connected to the middle of one of the rear longitudinal beam joints 320, the first rear cross member 330, the second rear cross member 340, the third rear cross member 350, and the fourth rear cross member 360 further reinforce the rear longitudinal beam joints 320 on both sides. The transverse beam body is arranged between the two rear longitudinal beams 310 and is a rear anti-collision beam 370, two ends of the rear anti-collision beam 370 are respectively connected to the rear ends of the rear longitudinal beams 310, and the combined outline of the rear anti-collision beam 370 and the rear longitudinal beams 310 is U-shaped and plays a role in anti-collision.

As shown in fig. 9, the cross section of the rear longitudinal beam 310 is generally vertical in a shape like a Chinese character 'ri', and the upper side wall of the rear longitudinal beam 310 extends to the left and right along the transverse direction, and is respectively provided with a third outer extension portion 311, so as to realize the fixed installation of corresponding components, as shown in fig. 13, the cross section of the rear anti-collision beam 370 is generally vertical in a shape like a Chinese character 'ri'; as shown in fig. 10, the cross section of the first rear cross member 330 is overall trapezoidal, the upper side wall and the lower side wall of the first rear cross member 330 both extend along the transverse direction and are respectively defined as two bottom edges of the trapezoid, and the lower side wall of the first rear cross member 330 extends along the transverse direction respectively to the front side and the rear side and is respectively formed with a fourth outward extending portion 331; as shown in fig. 11, the cross section of the second rear cross member 340 is a parallelogram with a bottom inclined to the front side, the upper side wall and the lower side wall of the second rear cross member 340 both extend in the transverse direction, the rear side of the upper side wall of the second rear cross member 340 extends to the rear and upward to form a fifth extended portion 341, and the front side of the lower side wall of the second rear cross member 340 extends to the front in the transverse direction to form a sixth extended portion 342; as shown in fig. 12, the cross section of the third rear cross member 350 is generally in a shape of a square, a seventh extending portion 351 is formed by extending the rear side of the upper side wall of the third rear cross member 350 rearward in the transverse direction, and an eighth extending portion 352 is formed by extending the front side of the upper side wall of the third rear cross member 350 downward and forward, so as to meet the internal strength requirements of the rear longitudinal member 310, the first rear cross member 330, the second rear cross member 340, the third rear cross member 350, the fourth rear cross member 360 and the rear impact beam 370, so as to facilitate extension or reduction of the size, and to fix and mount the corresponding components through the plurality of extending portions.

To sum up, the lower body frame structure provided by the embodiment of the present invention can be rapidly expanded to different sizes of vehicle models by extending or shortening the length of the front longitudinal beam 110, the threshold beam 210, the rear longitudinal beam 310, the front impact beam 130, the front cross beam 140, the front lower wall beam 150, the seat cross beam 220, the middle channel 230, the first rear cross beam 330, the second rear cross beam 340, the third rear cross beam 350, the fourth rear cross beam 360, and the rear impact beam 370 according to a certain proportion, and each of the above-mentioned beam bodies is an aluminum extruded part with a closed cross section, and can be directly produced and assembled after changing the size, without redesign and development of a mold, and ensure that the structural strength requirement can be satisfied after extending or shortening the size, and the front longitudinal beam joint 120 is connected between the engine compartment frame 100 and the front floor frame 200, and the rear longitudinal beam joint 320 is connected between the front floor frame 200 and the rear floor frame 300 to form a stable rigid connection structure, thereby greatly improving the development efficiency, shortening the development period and saving the production investment cost.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and replacements can be made without departing from the technical principle of the present invention, and these modifications and replacements should also be regarded as the protection scope of the present invention.

Claims

1. The lower vehicle body frame structure is characterized by comprising an engine compartment frame, a front floor frame and a rear floor frame which are sequentially connected from front to back;

2. The lower body frame structure according to claim 1, wherein the front side member, the rocker beam, the rear side member, each of the lateral beam bodies, and each of the longitudinal beam bodies are aluminum alloy members.

3. The lower body frame structure of claim 1, wherein the front rail joint and the rear rail joint are both cast parts.

4. The lower body frame structure according to claim 1, wherein the front side member is generally vertical in cross section in a "y" shape.

5. The lower body frame structure according to claim 1, wherein two of said lateral beam bodies, which are a front impact beam and a front cross beam, are provided between two of said front side members, both ends of said front impact beam are connected to a front end of one of said front side members, respectively, and both ends of said front cross beam are connected to a rear end of one of said front side members, respectively;

6. The lower body frame structure according to claim 5, wherein the cross section of the front impact beam is in a vertical shape like a Chinese character 'mu', and the cross section of the front cross beam is in a shape like a 'kou';

7. The lower body frame structure according to claim 1, wherein the threshold beam has a generally rectangular cross-section and an inner recess is provided at a junction of a lower side wall of the threshold beam and an outer side wall thereof;

8. The lower body frame structure according to claim 1, wherein two of said cross members are provided between two of said threshold beams, and are each a seat cross member, said seat cross members being spaced apart from each other from the front to the rear, both ends of said seat cross member being connected to a middle portion of one of said threshold beams,

9. The lower body frame structure according to claim 8, wherein the seat cross member has a transverse "herringbone" shape in cross section as a whole, and the lower side wall of the seat cross member extends in the transverse direction to the front and rear sides, respectively, and is formed with a first outward extending portion;

10. The lower body frame structure according to claim 1, wherein the rear side member has a vertical cross section in the shape of a letter "ri", and upper side walls of the rear side member extend in the lateral direction to the left and right sides, respectively, and are formed with third outward extending portions.

11. The lower body frame structure according to claim 1, wherein four of said transverse beams are disposed between two of said rear longitudinal beam joints, which are respectively a first rear cross beam, a second rear cross beam, a third rear cross beam and a fourth rear cross beam, said first rear cross beam, said second rear cross beam, said third rear cross beam and said fourth rear cross beam are sequentially spaced from front to rear, both ends of said first rear cross beam are respectively connected to a front end of one of said rear longitudinal beam joints, both ends of said fourth rear cross beam are respectively connected to a rear end of one of said rear longitudinal beam joints, both ends of said third rear cross beam and both ends of said fourth rear cross beam are respectively connected to a middle portion of one of said rear longitudinal beam joints,

12. The lower body frame structure according to claim 11, wherein the rear impact beam is generally vertical in cross section in a "y" shape;