CN118124679A - Rear girder assembly and vehicle - Google Patents

Abstract

The invention discloses a rear girder assembly and a vehicle, wherein the rear girder assembly comprises a rear girder; the rear girder is provided with a first installation part which can be matched with the torsion beam type suspension and the independent suspension; the first mounting part is provided with a mounting surface; when the rear girder is used for being connected with the torsion beam type suspension, a closed boss is formed on the mounting surface; and the rear girder is used for forming an avoidance hole on the mounting surface when the rear girder is connected with the independent suspension. The invention can make the rear girder which is adapted to the torsion beam type suspension and the rear girder which is adapted to the independent suspension share the same set of mould.

Description

Rear girder assembly and vehicle

Technical Field

The invention relates to the technical field of automobiles, in particular to a rear girder assembly and a vehicle.

Background

As a conventional walking tool for daily travel of people, automobiles are required to be provided with various configurations for meeting the needs of different people. In order to achieve the purpose of vibration reduction, a vibration reduction device is required to be installed on the rear girder.

The rear suspension is an important shock absorber for automobiles, and plays an important role in shock absorption and impact reduction of automobile bodies. In the prior art, for different rear suspension arrangements, it is necessary to develop different structural rear longerons to match the rear suspension mounting points. At present, the suspension is mainly divided into two structures, namely independent suspension and dependent suspension (torsion beam type suspension). To meet the two suspension configuration requirements, it is often necessary that the rear girder be designed in a different configuration.

The prior art rear girder requires development of a rear girder of a different structure for different suspension structures to match rear suspension mounting points. Development of rear girders of different structures can further lead to various improvements of the die, development and production costs are increased, and development period is prolonged.

In view of the above, how to enable the rear girders adapted to different types of suspensions to share the same mold is one of the important problems to be solved in the art.

Disclosure of Invention

The invention aims to provide a rear girder assembly and a vehicle, which are used for solving the problems in the prior art and enabling a rear girder which is adapted to torsion beam type suspension and a rear girder which is adapted to independent suspension to share the same set of dies.

The invention provides a rear girder assembly, which comprises a rear girder;

The rear girder is provided with a first installation part which can be matched with the torsion beam type suspension and the independent suspension;

the first mounting part is provided with a mounting surface;

when the rear girder is used for being connected with the torsion beam type suspension, a closed boss is formed on the mounting surface;

And the rear girder is used for forming an avoidance hole on the mounting surface when the rear girder is connected with the independent suspension.

The rear girder assembly as described above, wherein optionally the closing boss is integrally formed with the rear girder;

the closing boss can be cut to form the relief hole.

The rear girder assembly as described above, wherein optionally, the first mounting portion is further provided with a plurality of first mounting holes, and the plurality of first mounting holes are circumferentially arranged around the closed boss or the avoidance hole; the first mounting hole is used for connecting the torsion beam type suspension or independent suspension.

A rear girder assembly as described above, wherein, optionally, the rear girder has a second mounting portion and a third mounting portion formed thereon; the second mounting part is used for mounting a torsion beam type suspended spring seat or an independent suspended spring seat; the third mounting part is used for connecting the auxiliary frame.

The rear girder assembly as described above, wherein optionally the spring seat has at least two positions on the second mounting portion along a length direction of the rear girder to accommodate torsion beam type suspension and independent suspension spring seats, respectively.

A rear girder assembly as described above, wherein optionally, a spacer is further included, the spacer being located at one side of the spring seat of the rear casing Liang Beili;

two baffle mounting structures are arranged on the rear girder; the two baffle mounting structures are used for mounting the baffles which are hung differently.

A rear girder assembly as described above, wherein optionally, the rear girder is formed with a bulkhead position section between the two bulkhead mounting structures;

The partition plate is in a straight section.

A rear girder assembly as described above, wherein optionally, a girder reinforcing plate adapted to be independently suspended is further included;

The girder reinforcing plate suitable for independent suspension sequentially comprises a first structure, a second structure and a third structure along the length direction of the girder reinforcing plate;

the first structure and the third structure can be cut to form a girder reinforcing plate adapted to a torsion beam type suspension.

A rear girder assembly as described above, wherein optionally the third mounting portion is for arranging a subframe front mounting point and a subframe rear mounting point;

The subframe front mounting point and the subframe rear mounting point are arranged on the front and rear sides of the second mounting portion.

A rear girder assembly as described above, wherein optionally, the subframe front mounting point is provided with a front mounting point reinforcing plate;

and a rear mounting point reinforcing plate is arranged at the rear mounting point of the auxiliary frame.

A rear girder assembly as described above, wherein optionally, when adapted to a torsion beam type suspension, the girder reinforcing plate is located at the second mounting portion of the rear girder Liang Zhengdui;

When being adapted to independent suspension, the girder reinforcing plate extends from the second mounting portion to both sides to the sub-frame front mounting point and the sub-frame rear mounting point, respectively.

The invention also provides a vehicle, which comprises the rear girder assembly.

Compared with the prior art, the invention has at least the following beneficial effects:

The invention is provided with the first mounting part on the rear girder, and the closed boss is formed on the first mounting part to adapt to the torsion beam type suspension. That is, after molding by the mold, the first mounting portion of the rear girder is formed with a closed boss, which can be directly matched with the torsion beam type suspension. When the rear girder is used for being installed with independent suspension, the closed boss is required to be cut to form an avoidance hole, so that the rear girder is matched with the independent suspension. Meanwhile, a second installation part and a third installation part are arranged on the rear girder, and the second installation part can be independently adapted to torsion beam type suspension and independent suspension; the third installation part is used for connecting the auxiliary frame in order to meet the installation requirement of independent suspension. In this way, it is possible to make the rear girder adapted to the torsion beam type suspension and the rear girder adapted to the independent suspension share the same mold. The tooling investment cost can be reduced, and the new product research and development period can be shortened. The rear suspension system with two configurations is compatible through the rear girder, so that the number of parts can be reduced, and the serialization of the parts and the sharing rate of the parts are improved.

Drawings

Fig. 1 is a schematic structural view of a rear girder adapted to torsion beam suspension according to embodiment 1 of the present invention;

FIG. 2 is an enlarged partial schematic view of FIG. 1;

FIG. 3 is a schematic view of a rear girder adapted to be independently suspended according to embodiment 1 of the present invention;

FIG. 4 is an enlarged partial schematic view of FIG. 3;

fig. 5 is a schematic view showing the installation structure of a spring seat adapted to torsion beam suspension according to embodiment 1 of the present invention;

FIG. 6 is a perspective view of FIG. 5;

FIG. 7 is a schematic view showing a mounting structure of a spring seat adapted for independent suspension according to embodiment 1 of the present invention;

FIG. 8 is a perspective view of FIG. 7;

FIG. 9 is a schematic view of a spring seat adapted for torsion beam suspension according to embodiment 1 of the present invention;

FIG. 10 is a schematic view showing the installation of a spacer adapted to torsion beam type suspension according to embodiment 1 of the present invention;

FIG. 11 is a schematic view showing two mounting positions of a partition board according to embodiment 1 of the present invention;

FIG. 12 is a schematic view of a spring seat adapted for independent suspension according to embodiment 1 of the present invention;

FIG. 13 is a schematic view showing the installation of a separator adapted for independent suspension according to embodiment 1 of the present invention;

FIG. 14 is a schematic view showing the structure of a girder reinforcing plate adapted to a torsion beam type suspension according to embodiment 1 of the present invention;

FIG. 15 is a schematic view showing the installation structure of a girder reinforcing plate adapted to a torsion beam type suspension according to embodiment 1 of the present invention;

fig. 16 is a perspective view of fig. 15 at another view angle;

FIG. 17 is a schematic view of a girder reinforcing plate adapted to be independently suspended according to embodiment 1 of the present invention;

FIG. 18 is a schematic view showing the installation structure of a girder reinforcing plate adapted to be independently suspended according to embodiment 1 of the present invention;

fig. 19 is a perspective view of fig. 18 at another view angle;

FIG. 20 is a schematic view showing the overall structure of a rear girder adapted to torsion beam type suspension according to embodiment 1 of the present invention;

FIG. 21 is a schematic view showing the overall structure of a rear girder adapted for independent suspension according to embodiment 1 of the present invention;

fig. 22 is a schematic view showing a mounting structure of a rear girder and a spring seat adapted to be independently suspended according to embodiment 1 of the present invention.

Reference numerals illustrate:

1-a rear girder, wherein the rear girder is provided with a plurality of rear girders,

11-A first installation part, 12-a second installation part, 13-a third installation part, 14-a partition plate, 15-a partition plate position interval and 16-a girder reinforcing plate;

111-closing the boss, 112-avoiding the hole, 113-first mounting hole;

121-spring seats, 122-second mounting holes;

131-subframe front mounting point, 132-subframe rear mounting point, 133-front mounting point reinforcing plate, 134-rear mounting point reinforcing plate, 135-third mounting hole, 136-fourth mounting hole.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.

Example 1

Referring to fig. 1 to 22, the present embodiment provides a rear girder assembly, which includes a rear girder 1. The rear girder is used to support the entire rear suspension system.

The rear girder 1 is formed with a first installation part 11 capable of adapting to torsion beam type suspension and independent suspension; that is, the first mounting portion 11 can be adapted to both torsion beam suspension and independent suspension.

In order to realize the capability of respectively adapting to torsion beam type suspension and independent suspension, the first mounting part 11 is provided with a mounting surface; when the rear girder 1 is connected with the torsion beam type suspension, a closed boss 111 is formed on the mounting surface; when the rear girder 1 is connected with the independent suspension, the installation surface is cut to form an avoidance hole 112. In this way, the rear girder 1 suitable for torsion beam suspension and the rear girder 1 suitable for independent suspension can share the same set of mold, which is beneficial to reducing production cost.

In particular, the closing boss 111 may be directly formed integrally with the rear girder 1 in order to further reduce the production process, particularly the process when producing the rear girder adapted to the torsion beam type suspension. That is, the closing boss 111 can be cut to form the escape hole 112. When the rear girder 1 is used for independent suspension, the closed bosses 111 are cut to form the escape holes 112.

In one implementation, referring to fig. 1 to 5, the rear girder 1 is formed with a first mounting portion 11 capable of being connected to a trailing arm of a torsion beam type suspension; the first mounting portion 11 is formed with a closing boss 111 adapted to the torsion beam type suspension. Specifically, the first mounting portion 11 is further provided with a plurality of first mounting holes 113, and the plurality of first mounting holes 113 are arranged around the circumference of the closing boss 111. The plurality of first mounting holes 113 can be connected to both the trailing arms of the torsion beam type suspension and the trailing arms of the independent suspension. In the specific implementation, the trailing arms of the torsion beam type suspension may be connected to all the first mounting holes 113, or may be connected to part of the first mounting holes 113; the independently suspended trailing arms may be connected to all of the first mounting holes 113, or may be connected to a part of the first mounting holes 113.

Referring to fig. 1 to 4, when the rear girder 1 is connected to the independent suspension, the independent suspension trailing arm needs to be avoided, and the avoiding position corresponds to the position of the closed boss 111, so as to adapt to the connection mode in practical implementation. The closing boss 111 can be cut to form the relief hole 112; after the closing boss 111 is cut, the first mounting portion 11 can be fitted with an independently suspended trailing arm. In a specific implementation, after the rear girder 1 is formed, the closing boss 111 may be cut by means of laser cutting holes. It should be noted that the escape holes 112 formed by means of laser cutting holes should have a shape adapted to the independent suspension, and the escape holes 112 do not affect the arrangement of the first mounting holes 113, i.e., the plurality of first mounting holes 113 are located at the circumferential side of the escape holes 112. In a preferred implementation, the number of first mounting holes 113 is four. Through the mode, the rear girder which is hung by the adaptive torsion beam and the rear girder which is independently hung by the adaptive torsion beam can share the die, the number and the types of structural reinforcement parts are reduced while the strength requirements of different rear hanging installation points are met, the structure is light, and the die investment cost is reduced.

In order to realize the connection between the first mounting portion 11 and the torsion beam type suspension or independent suspension, the first mounting portion 11 is further provided with a plurality of first mounting holes 113, and the plurality of first mounting holes 113 are circumferentially arranged around the closed boss 111 or the avoidance hole 112; the first mounting hole 113 is used to connect the torsion beam type suspension or independent suspension. The torsion beam suspension and the independent suspension may share all or part of the first mounting hole 113 for a particular application.

Referring to fig. 5 to 9, in the embodiment, the torsion beam type suspension needs to be installed with a spring seat in addition to the trailing arm; independent suspension requires installation of a subframe in addition to the trailing arm and spring seat. In order to adapt the installation of the spring seat 121 and the subframe, the rear girder 1 is formed with a second installation portion 12 and a third installation portion 13; the second mounting part 12 is used for mounting a torsion beam type suspended spring seat or an independent suspended spring seat; the third mounting portion 13 is used for connecting with a subframe. Through the mode, the requirements of different hard point arrangements and chassis performance of the independent suspension and torsion beams are met, and a new design concept and design thought are provided for the design of the suspension mounting points after the subsequent vehicle type. By the mode, repeated design of the rear girder can be avoided, development period can be shortened, and market demands for updating and iterating of various vehicle types can be met. Specifically, referring to fig. 5 and 7, for the torsion beam type suspension, the distance between the second mounting portion 12 and the first mounting portion 11 is a1, and for the independent suspension, the distance between the second mounting portion 12 and the first mounting portion 11 is a2; the difference between the two distances is the distance between the spring seats suitable for two suspensions.

In particular, the rear girder 1 is manufactured by a thermoforming process in order to secure structural strength of the rear girder 1.

Referring to fig. 5 to 7, in order to accommodate different rear suspensions, a spring seat 121 is provided on the second mounting portion 12. The spring seat 121 has at least two positions along the length direction of the rear girder 1 on the second mounting portion 12 to accommodate torsion beam type suspension and independent suspension spring seats, respectively. In a specific implementation, in order to ensure that the spring seat 121 can be used for torsion beam suspension and independent suspension, the position of the rear girder 1 corresponding to the second mounting portion 12 is preferably in a flat structure, that is, the spring seat 121 can be attached to the rear girder 1 at two positions. In particular, at least two matching surfaces are provided between the spring seat 121 and the rear girder 1. For example, top and side surfaces; in specific implementation, the spring seat 121 keeps the fit state with the Z-direction matching surface of the rear girder 1, the Z-direction matching surface moves horizontally to a required position according to the coordinate axis X, the Y-direction matching surface is changed according to the rear large Liang Xingmian, the serial design of the rear spring seat is completed, and the mounting point of the auxiliary frame is newly added for the independent suspension structure, so that the strength requirement of the whole vehicle after the a1 value is lengthened is met, the requirements of different hard points of independent suspension and torsion girders for arrangement and chassis performance are met, and a new design concept and design thought are provided for the design of the rear suspension mounting point of a subsequent vehicle type. In specific implementation, the spring seat 121 is connected with the rear girder 1 by welding or bolting. In a specific implementation, the spring seat 121 is provided with a second mounting hole 122, and the second mounting hole 122 is used for mounting a torsion beam type suspended mounting plate or an independent suspended mounting plate.

Referring to fig. 9 to 12, in the embodiment, the spring seat 121 is mainly subjected to the Z-direction force F of the rear suspension spring, and in order to improve the dynamic stiffness and the overall strength of the spring seat mounting point, the embodiment further includes a partition 14, where the partition 14 is located at a side of the rear girder 1 facing away from the spring seat 121. The diaphragm 14 has two positions on the rear girder 1 to reinforce two positions corresponding to the spring seat 121, respectively. Specifically, two partition plate mounting structures are arranged on the rear girder 1; two of the diaphragm mounting structures are used to mount the diaphragm 14 for different suspensions. A partition plate position interval 15 is formed between the two partition plate mounting structures of the rear girder 1; the partition plate location area 15 is a flat section. Referring to fig. 11, in the present invention, two sets of partition board positions are connected to each other to obtain a partition board position section 15, denoted by w, and in the embodiment, the length of the partition board position section 15 in the front-rear direction is 180 to 220 mm, preferably 200 mm, and the relative distance t between the two sets of partition boards is 80 to 84 mm, preferably 82 mm. That is, a bulkhead position section 15 is formed in the rear girder 1, and the bulkhead 14 is positioned in the bulkhead position section 15 at two positions on the rear large scale; the flat design is adopted on the lap joint surface of the rear girder 1 corresponding to the partition plate 14, so that the partition plate 14 is shared, and the die investment cost is saved; during specific production, the fixture locating pin is designed to be of a sliding structure, the sliding stroke is set to be not smaller than the relative distance between two groups of partition boards, the clamping and locating requirements of the same fixture on different partition board positions are met, and the development cost and period of the fixture are saved; through above-mentioned baffle position adjustable design, realize a back girder construction to the strengthening of different suspension spring holder mounting points to satisfy the whole car performance demand of two kinds of suspension configurations simultaneously. Compared with the case where the separator 14 is directly provided to cover the separator position section 15, the present embodiment has a smaller weight, which is advantageous for weight saving. In the concrete implementation, in the partition plate position interval 15, the lap joint surfaces of the rear girder 1 and the partition plate 14 are all in a flat design, so that the partition plate 14 and the tool clamp can be shared by the torsion beam type suspension and the independent suspension. By this arrangement, the same bulkhead 14 can be fitted to the rear girder at any position of the bulkhead position section 15.

Referring to fig. 12 and 19, in order to adapt the independent suspension, the third mounting portion 13 is used for disposing a front sub-frame mounting point 131 and a rear sub-frame mounting point 132; the subframe front mounting point 131 and the subframe rear mounting point 132 are arranged on the front and rear sides of the second mounting portion 12.

Referring to fig. 19, 21 and 22, the independent suspension structure is often more stressed than torsion beam suspension, and in order to meet the requirements of bearing performance and comfort, the independent suspension is usually provided with a group of auxiliary frame mounting points and reinforcing plates than the torsion beam suspension to improve the structural strength of the independent suspension structure. For rear suspension mounting points, it is difficult to meet the strength requirement only by the rear girder 1, and the front mounting point reinforcing plate 133, the rear mounting point reinforcing plate 134 and the girder reinforcing plate 16 are newly added to promote the mounting point strength. Specifically, a front mounting point reinforcing plate 133 is provided at the subframe front mounting point 131. A rear mounting point reinforcing plate 134 is provided at the sub-frame rear mounting point 132.

The front mounting point reinforcing plate 133 is welded with the rear girder 1, and a third mounting hole 135 is formed in the front mounting point reinforcing plate 133. The rear mounting point reinforcing plate 134 is welded to the rear girder 1, and a fourth mounting hole 136 is formed in the rear mounting point reinforcing plate 134.

Referring to fig. 22, in order to further improve the structural strength of the rear girder 1 in the embodiment, the girder reinforcing plate 16 is further included in the present embodiment; the girder reinforcing plate 16 serves to reinforce a position between the subframe front mounting point 131 to the subframe rear mounting point 132.

When adapted to torsion beam suspension, the girder reinforcing plate 16 is located at a position where the rear girder 1 is opposite to the second mounting portion 12; when adapted for independent suspension, the girder reinforcing plate 16 extends from the second mounting portion 12 to both sides to the sub-frame front mounting point 131 and the sub-frame rear mounting point 132, respectively. The girder reinforcing plates 16 adapted for torsion beam type suspension are part of girder reinforcing plates 16 adapted for independent suspension; so that the girder reinforcing plates 16 adapted to the torsion beam type suspension share the mold with the girder reinforcing plates 16 adapted to the independent suspension.

Referring to fig. 14 and 17, the conventional vehicle model is generally designed to have a rear suspension mounting point and a corresponding rear girder reinforcing plate according to a single suspension structure, and the torsion beam structure directly uses the single suspension rear girder reinforcing plate or a new torsion beam reinforcing plate special member.

In this embodiment, in practical use, the required length of the girder erection reinforcing plate 16 is different due to the different suspension types. In one implementation, the independently suspended girder reinforcing plates 16 include a first structure, a second structure, and a third structure in order along their length directions. In a specific implementation, the first structure, the second structure and the third structure may be formed by an integral molding manner.

The first and third structures can be cut to form a girder reinforcing plate 16 adapted to a torsion beam type suspension. Wherein the second structure may act as a beam stiffener 16 for accommodating torsion beam suspensions.

In practical application, the first structure and the third structure can be cut off from the second structure, and the obtained second structure is the girder reinforcing plate 16 of the torsion beam type suspension vehicle type; referring to fig. 17, taking the length of the first structure as S1, the length of the second structure as u, and the length of the third structure as S2 as an example, by adding a first-order blanking die and blanking and forming according to the torsion mark line on the part number die, the sheared length is s1+s2, that is, the length of the girder reinforcing plate 16 of the torsion beam type suspension vehicle is u, the girder reinforcing plates 16 with two lengths are produced by the same set of die, the serialization design of the girder reinforcing plates 16 is completed, and the reinforcing effect and performance requirements of the torsion beam type suspension and independent suspension mounting points are met. The girder reinforcing plate series design reduces the weight of the torsion beam suspended vehicle body parts on the premise of not increasing the die cost, meets the light weight design requirement of the parts, and saves the die investment cost; and the joint surfaces and the relative positions of the two girder reinforcing plates 16 and the rear girder 1 are completely the same, so that one set of fixture can clamp and position two suspended rear girder welded parts, and the investment cost of the fixture is saved.

Through the sharing and serialization design of 4 parts such as the rear girder 1, the rear spring seat 121, the partition plate 14, the girder reinforcing plate 16 and the like, and only two independent suspension special parts such as the front mounting point reinforcing plate 133 and the rear mounting point reinforcing plate 133 are added, the structural difference of the welded parts of the left rear girder and the right rear girder is reduced to a great extent, other sub-level parts are shared parts except for 6 parts, the structures of the torsion beam type hanging and the independent hanging configured rear girder welded parts are basically consistent, the structural lightweight design requirement is met, and the same set of tool fixture is ensured to be compatible with the two hanging configured rear girder welded parts simultaneously.

Example 2

This embodiment is a further improvement on the basis of embodiment 1, and the same points are not described in detail, and only the differences are described below.

This embodiment proposes a vehicle including the rear girder assembly of embodiment 1 having at least two welding modes to respectively adapt torsion beam suspension and independent suspension.

It is to be noted that, in the above embodiments 1 and 2, the references to "front", "rear", "left", "right" coincide with the references to "front", "rear", "left", "right" of the corresponding vehicle body. The X direction refers to the front-rear direction of the vehicle body, the Y direction refers to the left-right direction of the vehicle body, and the Z direction is the vertical direction.

While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims (12)

1. A rear girder assembly, characterized by comprising a rear girder (1);

A first installation part (11) which can be matched with the torsion beam type suspension and the independent suspension is formed on the rear girder (1);

The first mounting part (11) is provided with a mounting surface;

when the rear girder (1) is used for being connected with the torsion beam type suspension, a closed boss (111) is formed on the mounting surface;

The rear girder (1) is used for forming an avoidance hole (112) on the installation surface when the rear girder is connected with the independent suspension.

2. The rear girder assembly according to claim 1, wherein the closing boss (111) is integrally formed with the rear girder;

The closing boss (111) can be cut to form the relief hole (112).

3. The rear girder assembly according to claim 1, wherein the first mounting portion (11) is further provided with a plurality of first mounting holes (113), and a plurality of the first mounting holes (113) are circumferentially arranged around the closing boss (111) or the escape hole (112); the first mounting hole (113) is used for connecting the torsion beam type suspension or independent suspension.

4. The rear girder assembly according to claim 1, wherein the rear girder (1) is formed with a second mounting portion (12) and a third mounting portion (13); the second mounting part (12) is used for mounting a torsion beam type suspended spring seat (121) or an independent suspended spring seat (121); the third mounting part (13) is used for connecting the auxiliary frame.

5. The rear girder assembly according to claim 4, characterized in that the spring seat (121) has at least two positions on the second mounting portion (12) along the length direction of the rear girder (1) to accommodate torsion beam suspension and independently suspended spring seats (121), respectively.

6. The rear girder assembly according to claim 4, further comprising a spacer (14), the spacer (14) being located on a side of the rear girder (1) facing away from the spring seat (121);

two partition plate mounting structures are arranged on the rear girder (1); two of the diaphragm mounting structures are used to mount the diaphragms (14) for different suspensions.

7. The rear girder assembly according to claim 6, wherein the rear girder (1) is formed with a bulkhead position section (15) between two of the bulkhead mounting structures;

The partition plate position section (15) is a straight section.

8. The rear girder assembly according to any of claims 4-7, further comprising a girder reinforcement plate (16) adapted to be suspended independently;

the girder reinforcing plate (16) which is suitable for independent suspension sequentially comprises a first structure, a second structure and a third structure along the length direction;

the first and third structures can be cut to form a girder reinforcing plate (16) adapted to a torsion beam suspension.

9. The rear girder assembly according to claim 8, wherein the third mounting portion (13) is for arranging a subframe front mounting point (131) and a subframe rear mounting point (132);

The subframe front mounting point (131) and the subframe rear mounting point (132) are arranged on both front and rear sides of the second mounting portion (12).

10. The rear girder assembly according to claim 9, wherein a front mounting point reinforcing plate (133) is provided at the subframe front mounting point (131);

A rear mounting point reinforcing plate (134) is arranged at the rear mounting point (132) of the auxiliary frame.

11. The rear girder assembly according to claim 9, characterized in that the girder reinforcement plate (16) is located at a position where the rear girder (1) is opposite to the second mounting portion (12) when adapted to torsion beam suspension;

When adapted for independent suspension, the girder reinforcing plate (16) extends from the second mounting portion (12) to both sides to the sub-frame front mounting point (131) and the sub-frame rear mounting point (132), respectively.

12. A vehicle comprising a rear girder assembly according to any one of claims 1 to 11.