CN211032741U

CN211032741U - Tank type transport semi-trailer and supporting device thereof

Info

Publication number: CN211032741U
Application number: CN201921969786.2U
Authority: CN
Inventors: 房坤; 吴标; 瞿绘军
Original assignee: Yangzhou CIMC Tonghua Special Vehicles Co Ltd
Current assignee: Yangzhou CIMC Tonghua Special Vehicles Co Ltd
Priority date: 2019-11-14
Filing date: 2019-11-14
Publication date: 2020-07-17
Anticipated expiration: 2029-11-14

Abstract

The utility model provides a tank-type transportation semitrailer and strutting arrangement thereof. The supporting device comprises a supporting frame and two supporting legs. The supporting frame comprises two left and right opposite supporting leg connecting supports, two supporting top plates which are respectively fixed at the upper ends of the two supporting leg connecting supports in a flat manner, and a connecting cross beam fixedly connected between the two supporting leg connecting supports; the connecting beam is positioned at the middle-lower part of the two leg connecting brackets, so that a space is formed between the connecting beam and the supporting top plate; the two legs are detachably connected to the outer sides of the two leg connecting supports respectively. Through the position decline that will connect the crossbeam, it is nearer to make the crossbeam of connecting from the liftoff focus of landing leg, the better atress condition that satisfies the landing leg has strengthened strutting arrangement's overall stability. And the position of the connecting beam is lowered to enable the connecting beam and the supporting top plate to have intervals, so that the pipeline of the tank body is conveniently accommodated, the problem of interference between the pipeline at the lower part of the tank body and the supporting device is effectively solved, and the pipeline arrangement is convenient.

Description

Tank type transport semi-trailer and supporting device thereof

Technical Field

The utility model relates to the technical field of vehicles, in particular to tank type transportation semitrailer and strutting arrangement thereof.

Background

The tank type transport semi-trailer is a road transport semi-trailer which is used for transporting liquid, gas and other substances and is provided with a tank body permanently installed on an unpowered semi-trailer travelling mechanism. When the semi-trailer needs to be unhooked or hung, the semi-trailer needs to be fixed by using the support legs arranged at the front part of the frame.

The supporting structure in the prior art comprises supporting legs and a supporting bracket, wherein the supporting legs are in the form of overhead supporting legs, the supporting bracket is welded on a lateral web plate of the semitrailer, and the overall stability of the supporting structure is poor.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a strutting arrangement that stability is good and have this strutting arrangement's pot-type transportation semitrailer to solve the problem among the prior art.

In order to solve the technical problem, the utility model provides a supporting device of tank-type transportation semitrailer, include: the supporting frame comprises two left and right opposite supporting leg connecting supports, two supporting top plates which are respectively fixed at the upper ends of the two supporting leg connecting supports in a flat manner, and a connecting cross beam which is fixedly connected between the two supporting leg connecting supports; the connecting cross beam is positioned at the middle lower part of the two supporting leg connecting brackets, so that a space is reserved between the connecting cross beam and the supporting top plate; the two support legs are detachably connected to the outer sides of the two support leg connecting supports respectively.

In one embodiment, a reinforcing plate is disposed between each supporting top plate and the connecting cross beam, the reinforcing plates are fixed to the connecting cross beam, the supporting top plates and the leg connecting bracket, and the two reinforcing plates are spaced from each other to form an accommodating space therebetween.

In one embodiment, the reinforcing plate includes a right trapezoid reinforcing main plate and a reinforcing flange formed by bending an oblique side of the reinforcing main plate, the reinforcing flange is bent in a direction away from the connecting beam, the reinforcing flanges of the two reinforcing plates are arranged oppositely, the top of the reinforcing body is fixed to the supporting top plate, and the other end of the reinforcing body, opposite to the reinforcing flange, is fixed to the supporting leg connecting bracket.

In one embodiment, the connecting beam comprises a zigzag beam main body and an extending edge integrally and upwardly extending from the top of the beam main body, and the extending edge is attached and bonded to one side of the bottom of the main board of the reinforcing board.

In one embodiment, the leg connecting bracket includes: the reinforcing body inclines relative to the support top plate to enable the connecting bracket main body to form a structure with a narrow bottom.

In one embodiment, the reinforcing bodies of the two leg connecting brackets extend oppositely and are respectively perpendicular to the respective bracket main bodies, the bracket main bodies form a mounting part above the reinforcing bodies, and the mounting part and the top of the reinforcing bodies form a supporting structure; the two connecting bracket main bodies respectively extend oppositely on the opposite sides of the reinforcing body to form side folding edges.

In one embodiment, the supporting top plate is provided with a plurality of assembling holes; a plurality of assembling holes are formed in the opposite positions, close to the tops, of the two supporting leg connecting supports; each landing leg connecting support is provided with a group of mounting holes on two sides of the connecting beam, and each group of mounting holes are used for connecting the landing legs.

In one embodiment, a plurality of the assembly holes are distributed into at least one group, and each group of the assembly holes are distributed at intervals along the longitudinal direction; the assembling holes are perpendicular to the installing holes of each group.

The utility model also provides a tank-type transportation semitrailer, include: the tank body, the traction module, the frame main body and the support device are arranged on the frame main body; the supporting device is characterized in that a supporting top plate of the supporting device is detachably connected with the tank body, a supporting leg connecting support of the supporting device is detachably connected with the frame main body, and a gap is reserved between the traction module and the supporting device.

In one embodiment, the support device is the support device as described above, the frame body includes two longitudinal beams disposed in parallel and opposite, the front end of each longitudinal beam is provided with at least one row of connecting holes distributed at intervals along the longitudinal direction, and the longitudinal beams and the support device are movably fitted and assembled in the longitudinal direction through the respective connecting holes and the respective assembly holes.

According to the above technical scheme, the utility model discloses an advantage lies in with positive effect:

the utility model discloses a strutting arrangement includes support frame and two landing legs. The support frame comprises two left and right opposite leg connecting supports, two supporting top plates which are respectively fixed at the upper ends of the two leg connecting supports in a flat mode and a connecting cross beam which is fixedly connected between the two leg connecting supports, wherein the connecting cross beam is located at the middle lower part of the two leg connecting supports, the position of the connecting cross beam is lowered, the connecting cross beam is close to the ground center of gravity of the legs, the stress condition of the legs is better met, and the overall stability of the support device is enhanced. And the position of the connecting beam is lowered to enable the connecting beam and the supporting top plate to have intervals, so that the pipeline of the tank body is conveniently accommodated, the problem of interference between the pipeline at the lower part of the tank body and the supporting device is effectively solved, and the pipeline arrangement is convenient. And the support frame and the two support legs are three independent modules, so that the support device has the advantages of small part number, simple structure, convenience in installation and high standardization degree.

The utility model discloses a tank-type transportation semitrailer includes the mutually independent jar body, pulls module, frame main part and strutting arrangement for this tank-type transportation semitrailer can separately make and separately transport, has reduced the degree of difficulty of making and commodity circulation transportation, has promoted economic benefits.

Drawings

FIG. 1 is a front view of one embodiment of the middle tank type transport semitrailer of the present invention;

FIG. 2 is a side view of one embodiment of the tank-type transportation semitrailer of the present invention;

FIG. 3 is a schematic view of the support device of FIG. 1 connected to the tank and the frame body according to the present invention;

FIG. 4 is a schematic structural view of the support frame of the present invention;

fig. 5 is a front view of the leg connecting bracket of the present invention;

FIG. 6 is a schematic structural view of a cross beam for connecting the support legs according to the present invention;

fig. 7 is a schematic structural view of the middle reinforcing plate of the present invention.

Wherein the reference numerals are as follows: 100. a tank transport semitrailer; 1. a tank body; 11. a tank body; 12. a support; 2. a traction module; 3. a frame main body; 31. a stringer; 4. a support device; 41. a support frame; 411. the supporting legs are connected with the bracket; 4111. connecting the bracket main body; 4112. a reinforcement body; 4113. folding the edges laterally; 4115. a main body portion; 4116. an assembling portion; 4117. an extension portion; 4118. an assembly hole; 4119. mounting holes; 412. supporting a top plate; 4121. assembling holes; 413. connecting the cross beam; 4131. a beam main body; 4132. an extension edge; 4136. a web; 4137. an upper flange plate; 4138. a lower flange plate; 414. a reinforcing plate; 4141. reinforcing the main board; 4142. reinforcing and folding edges; 42. and (7) supporting legs.

Detailed Description

Exemplary embodiments that embody features and advantages of the present invention will be described in detail in the following description. It is to be understood that the invention is capable of other and different embodiments and its several details are capable of modification without departing from the scope of the invention, and that the description and drawings are to be regarded as illustrative in nature and not as restrictive.

For further explanation of the principles and construction of the present invention, reference will now be made in detail to the preferred embodiments of the present invention, which are illustrated in the accompanying drawings.

Referring to fig. 1 and 2, the utility model provides a tank type transport semi-trailer 100, mainly includes a jar body 1, traction module 2, frame main part 3 and strutting arrangement 4. Wherein, strutting arrangement 4 can be dismantled with jar body 1 and be connected, strutting arrangement 4 can be dismantled with frame main part 3 and be connected, has the interval between traction module 2 and the strutting arrangement 4, and above-mentioned four parts are separable structure promptly for can-type transportation semitrailer 100 can separately make and separately transport, has reduced the degree of difficulty of making and commodity circulation transportation, has promoted economic benefits.

For the convenience of describing the position, the utility model discloses use the width direction of can-type transportation semitrailer 100 to be horizontal, use the length direction of can-type transportation semitrailer 100 to be vertical.

The can body 1 includes a can body 11 and a support 12. The tank body 11 is used for bearing materials, and the support 12 is used for connecting the tank body 11 with the traction module 2, the frame main body 3 and the support device 4. In the present embodiment, a plurality of holders 12 are provided at intervals in the longitudinal direction. Bolt holes are formed in each support 12 and used for detachably connecting the traction module 2, the frame main body 3 and the supporting device 4 with the tank body 11 respectively.

The traction module 2 comprises a traction base plate and a traction pin. The towing pin is used for matching with the saddle of the towing vehicle, is fixed on the towing bottom plate and extends downwards to the towing bottom plate, and when the semitrailer is in butt joint with the towing vehicle, the towing pin extends into the saddle of the towing vehicle.

The support means 4 are spaced from the traction module 2. Specifically, the supporting device 4 and the traction module 2 are respectively designed into independent modules, the two modules are disconnected without a connecting structure, and the design meets the requirement of the bearing strength of the frame through stress analysis and special arrangement of the position of the support 12, and the purpose of weight reduction is achieved.

The frame body 3 mainly includes two longitudinal members 31 extending in the longitudinal direction. Specifically, the longitudinal beam 31 includes an upper wing plate and a lower wing plate arranged in parallel at an interval, and a web connected between the upper wing plate and the lower wing plate. The front end of the web of each longitudinal beam 31 is provided with at least one row of connecting holes distributed at intervals along the longitudinal direction. In this embodiment, the connection hole is a kidney-shaped hole.

Referring to fig. 3, the top of the support unit 4 is connected to the seat 12 of the can 1, and the support unit 4 is connected to the frame body 3 in the longitudinal direction. And the supporting device 4 is detachably connected with the tank body 1 and the frame main body 3 respectively, so that the tank body 1, the traction module 2, the supporting device 4 and the frame main body 3 of the tank type transport semi-trailer 100 can be manufactured separately and transported separately, the difficulty of manufacturing and logistics transportation is reduced, the tank type transport semi-trailer 100 meets the requirements of road transportation and the requirements of light weight of customers, and the economic benefit is greatly improved.

In particular, the support device 4 comprises a support frame 41 and two legs 42.

Referring to fig. 4, the supporting frame 41 includes two leg connecting brackets 411, two supporting top plates 412, two connecting beams 413 fixedly connected between the two leg connecting brackets 411, and two reinforcing plates 414.

The two leg connecting brackets 411 have a symmetrical structure and are arranged symmetrically left and right.

Referring to fig. 5, each leg connecting bracket 411 includes a connecting bracket main body 4111, a reinforcing body 4112, and side flanges 4113.

The connecting bracket main body 4111 is an integrally formed structure, and mainly includes a main body portion 4115, an extending portion 4117 extending downward from the main body portion 4115, a mounting portion 4116 extending rearward from the main body portion 4115, and a connecting portion connecting between the extending portion 4117 and the mounting portion 4116. The extending portion 4117 and the fitting portion 4116 are perpendicular to each other, and the rear end of the fitting portion 4116 extends rearward beyond the extending portion 4117 to provide the connecting portion with a slanted side. The connecting portion is triangular, and the stability is better, and then increases the overall rigidity of linking bridge main part 4111.

The main body 4115 has a long hole.

The mounting portion 4116 has a plurality of mounting holes 4118, the plurality of mounting holes 4118 are arranged in at least one group, each group of mounting holes 4118 is longitudinally spaced apart, in this embodiment, the mounting holes 4118 are arranged in an array of 2 rows × 5 columns, that is, two groups of mounting holes 4118 are included, each group of mounting holes 4118 includes five mounting holes 4118 longitudinally spaced apart, two groups of mounting holes 4119 are disposed on the extending portion 4117, two groups of mounting holes 4119 are longitudinally spaced apart and are respectively disposed on two sides of the elongated hole, each group of mounting holes 4119 includes a plurality of mounting holes 4119 spaced apart in the height direction, the extending portion 4117 is perpendicular to the mounting portion 4116, such that the groups of mounting holes 4119 are perpendicular to the mounting holes 4121, and the mounting holes 4121 are disposed at the rear end of the mounting holes 4119 in the longitudinal direction.

The connecting portion is provided with a triangular lightening hole to lighten the weight of the connecting support main body 4111.

The reinforcement 4112 is formed at the inclined edge of the connection part. The reinforcing bodies 4112 of the two leg connecting brackets 411 extend oppositely and perpendicularly to the respective connecting bracket main bodies 4111, and a supporting structure is formed between the top of the reinforcing body 4112 and the mounting portion 4116.

The side folds 4113 extend from one side of the connecting bracket body 4111 opposite to the reinforcing body 4112, and the side folds 4113 of the two connecting bracket bodies 4111 are disposed opposite to each other. The arrangement of the side folds 4113 enhances the structural stability of the connecting bracket body 4111.

Two top support plates 412 are flatly fixed to the upper ends of the two leg connecting brackets 411 respectively. Specifically, the support plate is provided with a plurality of assembly holes 4121. The fastener passes through the assembling hole 4121 and the bolt hole on the support 12 to realize the detachable connection of the support device 4 and the tank body 1.

In the lateral direction, both sides of the top support plate 412 extend beyond the connection bracket main body 4111. The supporting top plate 412 extends in the longitudinal direction with its rear end not exceeding the rear end of the fitting portion 4116. Preferably, the rear end of the top support plate 412 extends to the forward mounting hole 4118 on the mounting portion 4116.

The connection beam 413 is positioned at a middle-lower portion of the leg connection bracket 411 such that the connection beam 413 is spaced apart from the support top plate 412. That is, the connecting cross member 413 is fixedly connected to the lower portion of the main body portion 4115 of the connecting bracket main body 4111 and the middle-upper portion of the extending portion 4117, so as to increase the overall rigidity of the supporting bracket 41. The connection beam 413 is close to the gravity center of the supporting leg 42 from the ground by descending of the connection beam 413, so that the stress condition of the supporting leg 42 is better met, and the overall stability of the supporting device 4 is enhanced.

In the longitudinal direction, the connecting beam 413 is located between two sets of mounting holes 4119 on the extending portion 4117. Specifically, two sets of mounting holes 4119 are symmetrically disposed about the connection beam 413.

Referring to fig. 6, the connection beam 413 includes a beam body 4131 having a zigzag shape and an extension edge 4132 integrally extending upward from the top of the beam body 4131. Specifically, the beam body 4131 includes a web 4136, and upper and

lower flange plates

4137 and 4138 bent and extended from upper and lower ends of the web 4136, respectively, and the upper and

lower flange plates

4137 and 4138 are arranged on both sides of the web 4136. The web 4136 is also provided with a plurality of lightening holes.

The extending edge 4132 is formed by extending upward from the top of the upper flange plate 4137, and the extending edge 4132 is parallel to the web 4136. The provision of the extending edge 4132 increases the rigidity of the connecting beam 413.

The top of the extending edge 4132 is spaced from the top support plate 412 so that the connecting beam 413 is spaced from the top support plate 412. Specifically, the top of the extending edge 4132 does not exceed the bottom of the elongated hole in the height direction.

The two reinforcing plates 414 are respectively disposed between the top supporting plates 412 and the connecting beam 413, that is, the reinforcing plates 414 are disposed at two ends of the connecting beam 413, and the two reinforcing plates 414 are spaced apart from each other and form an accommodating space therebetween. This accommodation space conveniently holds the pipeline of jar body 1, the effectual problem of interfering between the pipeline of 1 lower part of jar body and strutting arrangement 4 of having solved makes things convenient for the pipeline to arrange.

Referring to fig. 7, the reinforcing plate 414 includes a right-angled trapezoidal reinforcing main plate 4141 and a reinforcing flange 4142 formed by bending the hypotenuse of the reinforcing main plate 4141.

The width of the main reinforcement plate 4141 gradually increases from top to bottom, so that the main reinforcement plate 4141 has an inclined edge. And a triangular lightening hole is arranged on the reinforced main plate 4141 to lighten the weight of the supporting frame 41.

The reinforcing flanges 4142 are located at the inclined edges of the main reinforcing plate 4141, and the reinforcing flanges are bent away from the connecting beam 413, and the reinforcing flanges 4142 of the two reinforcing plates 414 are oppositely disposed, so that the accommodating space between the two reinforcing plates 414 is gradually reduced from the top to the bottom.

The top of the reinforcement main plate 4141 is fixed to the support top plate 412 by bonding, one side of the bottom of the reinforcement main plate 4141 is attached to the extension edge 4132 of the cross member by bonding, and the right-angle edge of the reinforcement main plate 4141 is fixed to the leg connecting bracket 411 by bonding. In this embodiment, the reinforced main plate 4141 is fixed to the top supporting plate 412, the extending edge 4132 and the leg connecting bracket 411 by welding. In other embodiments, the fixing can be realized by various kinds of gluing, and the connection strength after the fixing meets the requirements.

In this embodiment, the support frame 41 is made of an aluminum alloy material, and compared with a conventional carbon steel material, the support frame 41 reduces the weight of the support device 4 by more than 60%. Experimental demonstration, finite element analysis demonstrate that this strutting arrangement 4's structure and material cooperation can satisfy the strength requirement, and feedback, this strutting arrangement 4's stable in structure satisfies the operation requirement simultaneously through the user uses.

The two legs 42 are detachably connected to the outer sides of the two leg connecting brackets 411, respectively. Specifically, the leg 42 includes a leg body and a leg mounting plate. The supporting leg mounting plate is provided with a connecting hole matched with the mounting hole 4119. When the supporting legs 42 are assembled with the supporting frame 41, the connecting holes are opposite to the mounting holes 4119, and the fasteners penetrate through the connecting holes and the mounting holes 4119.

When the supporting device 4 and the frame body 3 are assembled, the two longitudinal beams 31 are accommodated inside the leg connecting bracket 411, a web plate of the longitudinal beam 31 is attached to the inner side surface of the assembling portion 4116, and the adaptive fasteners are arranged in the assembling holes 4118 and the connecting holes in the longitudinal beam 31 in a penetrating manner, the frame body 3 moves back and forth relative to the leg connecting bracket 411 through the connecting holes in the longitudinal beam 31 so as to adjust the longitudinal overlapping length of the longitudinal beam 31 and the assembling portion 4116, namely, the longitudinal beam is movably adaptive assembled in the longitudinal direction, thereby realizing the length adjustment of the frame body 3 within a certain range, meeting different axle distances L, namely, the central distance between the traction module 2 and a first axle of the tank type transportation semi-trailer 100, the connecting holes in the longitudinal beam 31 provide a larger moving space for the fasteners for designing the waist-shaped holes, realizing the fine adjustment of the front and back of the installation.

In the assembling process of the supporting device 4 with the frame body 3, the supporting structure formed between the top portion of the reinforcing body 4112 and the mounting portion 4116 supports the longitudinal beam 31, so that the supporting device 4 can support the frame body 3 more, and the load of the frame body 3 can be dispersed.

And the front end of the side member 31 abuts against the rear end of the support top plate 412, and the upper end surface of the ceiling wall of the side member 31 is flush with the upper end surface of the support top plate 412. In this way, the top support plate 412 abuts against the side member 31, and the top support plate 412 distributes the load in the longitudinal direction of the frame body 3, which is advantageous for maintaining the connection stability between the support device 4 and the frame body 3.

The support frame 41 and the two support legs 42 of the support device 4 are independent three modules, so that the support device 4 has the advantages of small number of parts, simple structure, convenience in installation and high standardization degree.

While the present invention has been described with reference to several exemplary embodiments, it is understood that the terminology used is intended to be in the nature of words of description and illustration, rather than of limitation. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.

Claims

1. A supporting device of a tank type transport semi-trailer is characterized by comprising:

the supporting frame comprises two left and right opposite supporting leg connecting supports, two supporting top plates which are respectively fixed at the upper ends of the two supporting leg connecting supports in a flat manner, and a connecting cross beam which is fixedly connected between the two supporting leg connecting supports; the connecting cross beam is positioned at the middle lower part of the two supporting leg connecting brackets, so that a space is reserved between the connecting cross beam and the supporting top plate;

the two support legs are detachably connected to the outer sides of the two support leg connecting supports respectively.

2. The support device for the tank type transport semi-trailer as claimed in claim 1, wherein a reinforcing plate is respectively arranged between each support top plate and the connecting cross beam, the reinforcing plates are respectively fixed with the connecting cross beam, the support top plates and the leg connecting bracket, and the reinforcing plates are spaced from each other and form a containing space therebetween.

3. The supporting device for tank type transportation semitrailer of claim 2, wherein the reinforcing plate comprises a right trapezoid reinforcing main plate and a reinforcing flange formed by bending the bevel edge of the reinforcing main plate, the reinforcing flange is bent away from the connecting cross beam, the reinforcing flanges of the two reinforcing plates are oppositely arranged, the top of the reinforcing main plate is fixed with the supporting top plate, and the other end of the reinforcing main plate opposite to the reinforcing flange is fixed with the leg connecting bracket.

4. The support device for tank type transport semi-trailer as claimed in claim 3, wherein said connection beam comprises a beam main body in a zigzag shape and an extension side integrally extended upward from the top of said beam main body, said extension side being attached and bonded to one side of the bottom of said reinforcing plate main plate.

5. The support device of the tank type transport semi-trailer as claimed in claim 1, wherein the leg connection bracket comprises: the reinforcing body inclines relative to the support top plate to enable the connecting bracket main body to form a structure with a narrow bottom.

6. The support device for tank type transport semi-trailers of claim 5, wherein the reinforcing bodies of the two leg connecting brackets extend oppositely and are perpendicular to the respective bracket bodies, the bracket bodies form a mounting part above the reinforcing bodies, and the mounting part and the top of the reinforcing bodies form a bearing structure;

the two connecting bracket main bodies respectively extend oppositely on the opposite sides of the reinforcing body to form side folding edges.

7. The support device of the tank type transport semi-trailer as claimed in claim 1, wherein a plurality of assembly holes are provided on the support top plate;

a plurality of assembling holes are formed in the opposite positions, close to the tops, of the two supporting leg connecting supports;

each landing leg connecting support is provided with a group of mounting holes on two sides of the connecting beam, and each group of mounting holes are used for connecting the landing legs.

8. The support device of a tank type transport semi-trailer as claimed in claim 7, wherein a plurality of the fitting holes are distributed in at least one group, each group being spaced apart in a longitudinal direction;

the assembling holes are perpendicular to the installing holes of each group.

9. A tank-type transport semitrailer, comprising: a tank, a traction module, a frame body and a support arrangement according to any one of claims 1 to 7; the supporting device is characterized in that a supporting top plate of the supporting device is detachably connected with the tank body, a supporting leg connecting support of the supporting device is detachably connected with the frame main body, and a gap is reserved between the traction module and the supporting device.

10. A tank-type transport semitrailer, comprising: a tank, a traction module, a frame body, and the support device of claim 8; the support top plate of the support device is detachably connected with the tank body, the frame main body comprises two longitudinal beams which are arranged in parallel and oppositely, at least one row of connecting holes which are distributed at intervals along the longitudinal direction are formed in the front end of each longitudinal beam, the longitudinal beams and the support device are movably matched and assembled in the longitudinal direction through the respective connecting holes and assembling holes, and a gap is formed between the traction module and the support device.