CN220640006U - Sub vehicle frame assembly and vehicle - Google Patents

Abstract

The utility model discloses a subframe assembly and a vehicle, wherein the subframe assembly comprises a subframe body and a reinforcing bracket, and the subframe body is provided with a plurality of first connecting parts for connecting with a vehicle body; the reinforcing support is fixedly arranged on the auxiliary frame body and is provided with a second connecting part used for being connected with the vehicle body. According to the auxiliary frame assembly, the technical effect that welding spots between the vehicle body bottom plate and the foot pit floor are not easy to tear during vehicle collision can be achieved.

Description

Sub vehicle frame assembly and vehicle

Technical Field

The utility model relates to the technical field of vehicles, in particular to a subframe assembly and a vehicle.

Background

In the prior art, the auxiliary frame assembly is in eight-point rigid connection with the vehicle body, the front end of the auxiliary frame assembly is in two-point rigid connection with the vehicle body, the middle end of the auxiliary frame assembly is in two-point rigid connection with the vehicle body, the rear end of the auxiliary frame assembly is in four-point rigid connection with the vehicle body, when the vehicle collides with the existing auxiliary frame assembly structure, the rear end of the auxiliary frame assembly is less in connection point with the vehicle body, the force transmitted to the auxiliary frame assembly after the vehicle body is stressed is smaller, the strength of the vehicle body is insufficient, the risk of welding spot tearing exists between the floor of the vehicle body and the foot pit floor of the vehicle body, safety penalty is generated, and the safety performance requirement is not met.

Therefore, the prior art subframe assembly has the problem that the welding point between the vehicle body bottom plate and the foot pit floor is easy to tear during vehicle collision.

Disclosure of Invention

The utility model aims to at least solve one of the technical problems that welding spots between a vehicle body bottom plate and a foot pit floor are easy to tear during vehicle collision in the prior art, and provides a subframe assembly and a vehicle.

In order to solve the technical problem, the utility model provides a subframe assembly, which comprises a subframe body and a reinforcing bracket, wherein the subframe body is provided with a plurality of first connecting parts for connecting with a vehicle body; the reinforcing support is fixedly arranged on the auxiliary frame body and is provided with a second connecting part used for being connected with the vehicle body.

Further, the auxiliary frame assembly further comprises a fixing piece, the fixing piece penetrates through the second connecting portion to be connected with the vehicle body, and gaps are respectively formed between the reinforcing support and the vehicle body and between the reinforcing support and the fixing piece.

Further, the subframe body comprises a front section, a middle section and a rear section which are sequentially connected, wherein the front section, the middle section and the rear section are connected with the vehicle body through first connecting parts respectively, and the rear section is connected with the reinforcing support.

Further, the reinforcing support comprises two connecting plates, the two connecting plates are arranged up and down and are connected with each other, the two connecting plates are connected with the auxiliary frame body, and the fixing piece sequentially penetrates through the two connecting plates and is connected with the vehicle body.

Further, the connecting plates are provided with through holes corresponding to the fixing pieces, and the fixing pieces sequentially penetrate through the through holes of the two connecting plates.

Further, the reinforcing bracket further comprises a connecting sleeve, at least one part of the connecting sleeve is arranged between the two connecting plates, at least one end of the connecting sleeve stretches into the through hole of the connecting plate, and the fixing piece penetrates through the connecting sleeve to be connected with the vehicle body.

Further, the diameter of the connecting sleeve is larger than that of the fixing piece, and a first gap is formed between the circumferential inner side wall of the connecting sleeve and the circumferential outer side wall of the fixing piece.

Further, the mounting includes connecting section and spacing section of connecting in order, and the connecting section passes two connecting plates and is connected with the automobile body, and spacing section sets up the one end of keeping away from the automobile body at the connecting section, and has the second clearance between the connecting plate of keeping away from the automobile body relatively in spacing section and the two connecting plates.

Another aspect of the utility model provides a vehicle comprising the subframe assembly described above.

Further, the vehicle further comprises a plurality of torsion boxes, the torsion boxes are arranged on the vehicle body, each reinforcing bracket is respectively and correspondingly arranged with at least one torsion box on the vehicle body, and the fixing piece of the auxiliary frame assembly corresponding to the reinforcing bracket is connected with the vehicle body through the torsion box; the blind hole installation sleeves are equal to the fixing pieces in number and correspond to each other one by one, at least one part of the blind hole installation sleeves is embedded in the torsion box, and the fixing pieces are connected with the torsion box through the blind hole installation sleeves.

The auxiliary frame assembly comprises an auxiliary frame body and a reinforcing bracket, wherein the auxiliary frame body is provided with a plurality of first connecting parts for connecting with a vehicle body; the reinforcing support is fixedly arranged on the auxiliary frame body and is provided with a second connecting part used for being connected with the vehicle body.

Through add the reinforcing support on sub vehicle frame assembly in this application, the sub vehicle frame body passes through first connecting portion and is connected with the automobile body, and when the vehicle collides, the sub vehicle frame assembly takes place the dislocation and passes through the second connecting portion contact with the newly-increased reinforcing support, can carry out the power transmission between the two, decompose the power to automobile body longeron outside automobile body torsion box through this structure to reduce the atress on longeron inboard foot hole floor, avoid the solder joint tearing, solve the problem that the security performance is unsatisfied.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are necessary for the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the following description are only some of the embodiments described in the utility model, and that other drawings can be obtained from these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic structural view of a subframe assembly according to an embodiment of the present utility model;

FIG. 2 is a schematic top view of a subframe assembly according to an embodiment of the present utility model;

FIG. 3 is a schematic cross-sectional view of the subframe assembly of FIG. 2 at a rear section in accordance with an embodiment of the utility model;

FIG. 4 is a schematic diagram of the structure of FIG. 3 at position A in accordance with an embodiment of the present utility model;

FIG. 5 is a schematic view of the structure of the side member and torsion box of the vehicle body in an embodiment of the present utility model;

fig. 6 is a schematic cross-sectional view of the embodiment of the utility model of fig. 5 at a blind hole installation sleeve.

Reference numerals:

1. a subframe assembly; 10. an auxiliary frame body; 11. a front section; 111. a front mounting hole; 12. an intermediate section; 121. a middle mounting hole; 13. a rear section; 131. a rear mounting hole; 20. reinforcing the support; 21. a connecting plate; 22. a through hole; 23. a connecting sleeve; 30. a fixing member; 31. a connection section; 32. a limiting section; 40. a gap; 41. a first gap; 42. a second gap; 2. a vehicle body; 210. a longitudinal beam; 50. a torsion box; 51. a first torsion box; 52. a second torsion box; 60. and a sleeve is arranged in the blind hole.

Detailed Description

Various aspects and features of the present utility model are described herein with reference to the accompanying drawings.

It should be understood that various modifications may be made to the embodiments of the application herein. Therefore, the above description should not be taken as limiting, but merely as exemplification of the embodiments. Other modifications within the scope and spirit of the utility model will occur to persons of ordinary skill in the art.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and, together with a general description of the utility model given above, and the detailed description of the embodiments given below, serve to explain the principles of the utility model.

These and other characteristics of the utility model will become apparent from the following description of a preferred form of embodiment, given as a non-limiting example, with reference to the accompanying drawings.

It is also to be understood that, although the utility model has been described with reference to some specific examples, a person skilled in the art will certainly be able to achieve many other equivalent forms of the utility model, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.

The above and other aspects, features and advantages of the present utility model will become more apparent in light of the following detailed description when taken in conjunction with the accompanying drawings.

Specific embodiments of the present utility model will be described hereinafter with reference to the accompanying drawings; however, it is to be understood that the disclosed embodiments are merely exemplary of the utility model, which can be embodied in various forms. Well-known and/or repeated functions and constructions are not described in detail to avoid obscuring the utility model in unnecessary or unnecessary detail. Therefore, specific structural and functional details disclosed herein are not intended to be limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present utility model in virtually any appropriately detailed structure.

The specification may use the word "in one embodiment," "in another embodiment," "in yet another embodiment," or "in other embodiments," which may each refer to one or more of the same or different embodiments in accordance with the utility model.

The utility model provides a subframe assembly and a vehicle, which aim to solve the problem that welding spots between a vehicle body bottom plate and a foot pit floor are easy to tear when the vehicle collides in the subframe assembly in the prior art.

The utility model provides a vehicle, which comprises a subframe assembly 1 and a vehicle body 2, wherein the subframe assembly 1 is connected with the vehicle body 2.

As shown in fig. 1 to 6, the subframe assembly 1 includes a subframe body 10, a reinforcing bracket 20, and a fixing member 30, wherein the subframe body 10 has a plurality of first connection portions for connection with the vehicle body 2; the reinforcing bracket 20 is fixedly provided on the sub-frame body 10, and the reinforcing bracket 20 has a second connection portion for connection with the vehicle body 2.

Through add the reinforcing bracket 20 on sub vehicle frame assembly 1 in this application, reinforcing bracket 20 symmetry sets up in the both sides of sub vehicle frame body 10, mounting 30 passes reinforcing bracket 20 and is connected with automobile body 2, when the vehicle bumps, sub vehicle frame assembly 1 takes place the dislocation and with newly-increased mounting 30 contact, decompose the force to the longeron 210 outside automobile body torsion box 50 of automobile body 2 through this structure to reduce the atress on longeron 210 inboard foot hole floor, avoid the solder joint tearing, solve the problem that the security performance is unsatisfied.

Preferably, in the present embodiment, there are two reinforcing brackets 20, and two fixing members 30, and two reinforcing brackets 20 are respectively connected to opposite ends of the subframe body 10, and each reinforcing bracket 20 is used for passing through one fixing member 30. Of course, the number of reinforcing brackets 20 and fasteners 30 may vary depending on the actual needs.

In the present embodiment, the vehicle body 2 includes two side members 210, a vehicle underbody, and a pit floor, wherein the two side members 210 are connected to the vehicle underbody, and the pit floor is welded to the vehicle underbody.

As shown in fig. 3 and 4, the fixing member 30 is connected to the vehicle body 2 through the second connecting portion. Gaps 40 are provided between the reinforcing brackets 20 and the vehicle body 2 and between the reinforcing brackets 20 and the fixing members 30, respectively. In this way, the reinforcing support 20 is not contacted with the vehicle body 2, the reinforcing support 20 is not contacted with the fixing piece 30, and when the vehicle collides, the reinforcing support 20 is directly contacted with the vehicle body 2, or the reinforcing support 20 is contacted with the vehicle body 2 through the fixing piece 30, so that the force transmission between the reinforcing support 20 and the vehicle body 2 is realized, and the problem of tearing of welding spots inside the vehicle body 2 is avoided.

As shown in fig. 2, the sub-frame body 10 includes a front section 11, a middle section 12, and a rear section 13 connected in sequence, the front section 11, the middle section 12, and the rear section 13 are connected to the vehicle body 2 by first connecting portions, respectively, and the reinforcing brackets 20 are connected to the rear section 13. In this way, the front section 11, the intermediate section 12, and the rear section 13 of the sub-frame body 10 are connected to the vehicle body 2 through a plurality of positions, increasing the reliability of the connection between the sub-frame body 10 and the vehicle body 2.

In this embodiment, the longitudinal beam 210 shown in fig. 5 is only a lower half portion of the longitudinal beam 210, the upper half portion of the longitudinal beam 210 is connected to the front section 11 and the middle section 12, the front section 11 includes at least two front mounting holes 111 symmetrically disposed, the front section 11 is rigidly connected to the longitudinal beam 210 of the vehicle body 2 through the at least two front mounting holes 111, the rear section 13 includes at least two rear mounting holes 131 symmetrically disposed, the rear section 13 is connected to the vehicle body 2 through the at least two rear mounting holes 131, the middle section 12 includes at least two middle mounting holes 121 symmetrically disposed, and the middle section 12 is rigidly connected to the longitudinal beam 210 of the vehicle body 2 through the at least two middle mounting holes 121, however, the middle section 12 may be provided without middle mounting holes according to actual needs, and the subframe body 10 is connected to the vehicle body 2 through the front mounting holes 111 and the rear mounting holes 131 only.

As shown in fig. 4, the reinforcing bracket 20 includes two connection plates 21, the two connection plates 21 are symmetrically disposed and connected to each other, the two connection plates 21 are connected to the sub-frame body 10, and the fixing member 30 sequentially passes through the two connection plates 21 and is connected to the vehicle body 2. In this way, the two connection plates 21 are connected to form the reinforcing bracket 20, facilitating the manufacture of the reinforcing bracket 20.

Preferably, in the present embodiment, two connection plates 21 symmetrically disposed are welded to form a reinforcing bracket 20, and the two reinforcing brackets 20 are welded to opposite sides of the sub-frame body 10.

As shown in fig. 4, the connection plates 21 are provided with the passing holes 22 corresponding to the fixing pieces 30, and the fixing pieces 30 sequentially pass through the passing holes 22 of the two connection plates 21. Thus, the passage holes 22 are provided for receiving the fixing members 30 to connect the fixing members 30 to the vehicle body 2 through the passage holes 22.

In this embodiment, the second connection portion includes a through hole 22.

Preferably, the aperture through the bore 22 is larger than the diameter of the mount 30.

As shown in fig. 4, the reinforcing bracket 20 further includes a connection sleeve 23, at least a portion of the connection sleeve 23 is disposed between the two connection plates 21, at least one end of the connection sleeve 23 extends into the passage hole 22 of the connection plate 21, and the fixing member 30 is connected to the vehicle body 2 through the connection sleeve 23. In this way, when the vehicle collides, the contact surface between the connecting sleeve 23 and the fixing piece 30 can be ensured to be larger by the arrangement of the connecting sleeve 23, and the larger the load which can be transmitted between the connecting sleeve 23 and the fixing piece 30 is, more force is decomposed to the torsion box 50 of the vehicle body outside the longitudinal beam 210 of the vehicle body 2, so that the stress of the foot pit floor inside the longitudinal beam 210 is reduced, and the tearing of welding spots is avoided.

In the present embodiment, the connection sleeve 23 is welded to the at least one connection plate 21 at the position of the through hole 22.

As shown in fig. 4, the diameter of the connection sleeve 23 is larger than the diameter of the fixing member 30, and a first gap 41 is provided between the circumferential inner side wall of the connection sleeve 23 and the circumferential outer side wall of the fixing member 30. Thus, when the vehicle is running normally, the circumferential outer side wall of the fixing member 30 is not in contact with the connecting sleeve 23, so that the problems of excessive local mounting points of the vehicle body 2 and the subframe body 10 in the region and over-constraint are prevented, and the process feasibility is satisfied; only when the vehicle collides, the circumferential inner side wall of the connecting sleeve 23 contacts the fixing member 30 and breaks down the load.

As shown in fig. 4, the fixing member 30 includes a connecting section 31 and a limiting section 32 connected in sequence, the connecting section 31 passes through the two connecting plates 21 and is connected with the vehicle body 2, the limiting section 32 is disposed at one end of the connecting section 31 away from the vehicle body 2, and a second gap 42 is provided between the limiting section 32 and one of the two connecting plates 21 which is relatively far from the vehicle body 2. Thus, the limiting section 32 can limit the reinforcing bracket 20 to prevent the subframe assembly 1 and the vehicle body 2 from being separated, and when the vehicle runs normally, the limiting section 32 is not in contact with the reinforcing bracket 20 to prevent over-constraint, and only when the vehicle collides, the limiting section 32 is in contact with the reinforcing bracket 20 to decompose the load.

In this embodiment, the diameter of the limiting section 32 is larger than the diameter of the connecting section 31.

In the present embodiment, a third gap is provided between the torsion box 50 and the connecting plate 21 that is relatively close to the vehicle body 2, of the two connecting plates 21.

In the present embodiment, the gap 40 includes a first gap 41, a second gap 42, and a third gap.

As shown in fig. 5 and 6, the vehicle further includes a plurality of torsion boxes 50, each reinforcing bracket 20 is disposed corresponding to at least one torsion box 50, and the corresponding fixing member 30 of the reinforcing bracket 20 is connected to the vehicle body 2 through the torsion box 50; in this way, the torsion box 50 can better transmit the load between the reinforcing bracket 20 and the vehicle body 2.

It should be noted that, in the present embodiment, the torsion box 50 includes at least two first torsion boxes 51 and at least two second torsion boxes 52, the first torsion boxes 51 and the second torsion boxes 52 are disposed on opposite sides of the longitudinal beam 210, and the first torsion boxes 51 and the second torsion boxes 52 are welded with the longitudinal beam 210, the first torsion boxes 51 connect the fixing member 30 and the vehicle body 2, and the second torsion boxes 52 connect the rear section 13 of the subframe body 10 and the vehicle body 2.

In this embodiment, two first torsion boxes 51 are provided, two second torsion boxes 52 are provided, wherein the two first torsion boxes 51, the two second torsion boxes 52 and the two stringers 210 are in one-to-one correspondence, the two second torsion boxes 52 are located between the two stringers 210, the two first torsion boxes 51 are located outside the two stringers 210, and of course, the first torsion boxes 51 and the second torsion boxes 52 may be provided with a plurality of torsion boxes according to the need.

Preferably, in the present embodiment, the front section 11 includes two front mounting holes 111, the two front mounting holes 111 are respectively connected with upper end positions of the two stringers 210 by bolts, the middle section 12 includes two middle mounting holes 121, the two middle mounting holes 121 are respectively connected with middle positions of the two stringers 210 by bolts, and the rear section 13 includes four rear mounting holes 131, wherein the two rear mounting holes 131 and the other two rear mounting holes 131 are symmetrically arranged, the two rear mounting holes 131 are connected with one second torsion box 52 by bolts, and the other two rear mounting holes 131 are connected with the other second torsion box 52 by bolts; of course, four second torsion boxes 52 may be provided, and four rear mounting holes 131 are connected with the four second torsion boxes 52 by bolts, respectively.

In this application, the first connection portion includes a front mounting hole 111, a middle mounting hole 121, and a rear mounting hole 131.

As shown in fig. 4 and 6, the vehicle further includes a plurality of blind hole mounting bushings 60, the blind hole mounting bushings 60 are equal in number and correspond to the fixing elements 30 one by one, at least a portion of the blind hole mounting bushings 60 are embedded inside the torsion box 50, and the fixing elements 30 are connected to the torsion box 50 through the blind hole mounting bushings 60. Thus, the fastener 30 is connected with the blind mounting sleeve 60 to meet the torque requirements of the fastener 30.

In this embodiment, the blind hole mounting sleeve 60 is internally provided with an internal thread, one end of the connecting section 31, which is far away from the limiting section 32, is provided with an external thread, and the connecting section 31 of the fixing member 30 is in threaded connection with the blind hole mounting sleeve 60.

According to the embodiment of the utility model, at least two reinforcing brackets 20 can be additionally arranged on the auxiliary frame assembly 1, the at least two reinforcing brackets 20 are symmetrically arranged on two sides of the auxiliary frame body 10, the fixing piece 30 passes through the reinforcing brackets 20 to be connected with the automobile body 2, when a vehicle collides, the additionally arranged two reinforcing brackets 20 are contacted with the automobile body 2 through the fixing piece 30, force transmission can be carried out between the two reinforcing brackets, when the vehicle collides, the auxiliary frame assembly 1 is staggered and contacted with the newly-added fixing piece 30, and the force is decomposed to the first torsion box 51 outside the longitudinal beam 210 of the automobile body 2 through the structure, so that the stress of the foot pit floor at the inner side of the longitudinal beam 210 is reduced, the tearing of welding spots is avoided, and the problem of unsatisfactory safety performance is solved.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present utility model.

In the description of the utility model, a "first feature" or "second feature" may include one or more of such features.

In the description of the present utility model, "plurality" means two or more.

In the description of the utility model, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, and may also include the first and second features not being in direct contact but being in contact with each other by another feature therebetween.

In the description of the utility model, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present utility model have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the utility model, the scope of which is defined by the claims and their equivalents.

Claims (9)

1. A subframe assembly, comprising:

a sub-frame body (10), the sub-frame body (10) having a plurality of first connection portions for connection with a vehicle body (2);

a reinforcing bracket (20), wherein the reinforcing bracket (20) is fixedly arranged on the auxiliary frame body (10), and the reinforcing bracket (20) is provided with a second connecting part for connecting with the vehicle body (2);

the auxiliary frame assembly further comprises a fixing piece (30), the fixing piece (30) penetrates through the second connecting portion to be connected with the vehicle body (2), and gaps (40) are respectively formed between the reinforcing support (20) and the vehicle body (2) and between the reinforcing support (20) and the fixing piece (30).

2. The subframe assembly according to claim 1, wherein the subframe body (10) comprises a front section (11), a middle section (12) and a rear section (13) connected in sequence, the front section (11), the middle section (12) and the rear section (13) being connected with the vehicle body (2) by the first connection, respectively, and the rear section (13) being connected with the reinforcing bracket (20).

3. The subframe assembly according to claim 1, wherein the reinforcing bracket (20) comprises:

the auxiliary frame comprises two connecting plates (21), wherein the two connecting plates (21) are arranged up and down and are connected with each other, the two connecting plates (21) are connected with the auxiliary frame body (10), and the fixing piece (30) sequentially penetrates through the two connecting plates (21) and is connected with the vehicle body (2).

4. A subframe assembly according to claim 3, wherein the connection plates (21) are provided with passage holes (22) corresponding to the fixing members (30), the fixing members (30) passing through the passage holes (22) of two connection plates (21) in sequence.

5. The subframe assembly according to claim 4, wherein the reinforcing bracket (20) further comprises a connection sleeve (23), at least a portion of the connection sleeve (23) is disposed between the two connection plates (21), at least one end of the connection sleeve (23) protrudes into the passage hole (22) of the connection plate (21), and the fixing member (30) is connected to the vehicle body (2) through the connection sleeve (23).

6. The subframe assembly according to claim 5, wherein the diameter of the connecting sleeve (23) is larger than the diameter of the fixing member (30), and wherein a first gap (41) is provided between a circumferential inner side wall of the connecting sleeve (23) and a circumferential outer side wall of the fixing member (30).

7. A subframe assembly according to claim 3, wherein the fixing member (30) comprises a connecting section (31) and a limiting section (32) which are sequentially connected, the connecting section (31) penetrates through two connecting plates (21) and is connected with the vehicle body (2), the limiting section (32) is arranged at one end, far away from the vehicle body (2), of the connecting section (31), and a second gap (42) is formed between the limiting section (32) and one of the two connecting plates (21), which is relatively far away from the vehicle body (2).

8. A vehicle, characterized by comprising a subframe assembly (1) according to any one of claims 1 to 7.

9. The vehicle of claim 8, characterized in that the vehicle further comprises:

the torsion boxes (50) are arranged on the vehicle body (2), each reinforcing bracket (20) is arranged corresponding to at least one torsion box (50) on the vehicle body (2), and the fixing piece (30) of the auxiliary frame assembly (1) corresponding to the reinforcing bracket (20) is connected with the vehicle body (2) through the torsion box (50);

the blind hole mounting sleeves (60) are equal in number and in one-to-one correspondence with the fixing pieces (30), at least one part of the blind hole mounting sleeves (60) is embedded in the torsion box (50), and the fixing pieces (30) are connected with the torsion box (50) through the blind hole mounting sleeves (60).