CN220842299U - Seat is with pipe rotation prevention limit assembly - Google Patents

Abstract

The utility model provides an anti-rotation limiting assembly for a pipe for a seat, which comprises a pipe body for the seat and limiting structures, wherein a pair of limiting structures are symmetrically formed at two ends of the pipe body for the seat respectively, so that the two ends of the pipe body for the seat are fixedly spliced on two wall plates through the limiting structures respectively. The utility model relates to the technical field of automobile seats, and can solve the problems that a seat front pipe is inconvenient to install and is not environment-friendly and the seat front pipe moves and rotates relative to a wallboard in the prior art.

Description

Seat is with pipe rotation prevention limit assembly

Technical Field

The utility model relates to the technical field of automobile seats, in particular to a pipe anti-rotation limiting assembly for a seat.

Background

The front tube in the automobile seat is an important transmission part for cushion movement, and the installation mode of the front tube of the seat in the prior art is as follows: the square pieces are welded at two ends of the front tube of the seat, and then are connected to the wall plates of the left and right revolute pairs through bolts.

The installation mode of the front tube of the seat in the prior art is inconvenient and not environment-friendly; meanwhile, the seat front pipe can move relative to the wall plate in the transverse direction and the longitudinal direction after being stressed, and can rotate relative to the wall plate after being stressed due to the fact that the seat front pipe is a round pipe, so that the installation and use stability of the seat front pipe are affected. Therefore, it is desirable to provide a seat tube anti-rotation limiting assembly, which can solve the problems of inconvenient installation of the seat front tube, environmental protection, movement and rotation of the seat front tube relative to the wall plate in the prior art.

Disclosure of utility model

In view of the above, the utility model provides a seat tube anti-rotation limiting assembly, which can solve the problems of inconvenient installation of a seat front tube, environmental protection and movement and rotation of the seat front tube relative to a wallboard in the prior art.

In order to achieve the above purpose, the technical scheme adopted by the utility model is as follows: the utility model provides a seat is with pipe anti-rotation limit assembly, includes seat and uses pipe body and limit structure, limit structure forms in seat and uses the both ends of pipe body, makes seat use the both ends of pipe body to fix on the wallboard through limit structure respectively.

In the embodiment of the utility model, the seat tube body is a round tubular body or a non-round tubular body; the wall plate is provided with an assembly hole for the pipe body for the seat to pass through, so that the wall plate is sleeved on the pipe body for the seat through the assembly hole.

In the embodiment of the utility model, when the seat tube body is a circular tubular body, a flower-shaped hole is formed at the edge of the assembly hole, and the material of the seat tube body is extruded into the flower-shaped hole.

In the embodiment of the utility model, the limiting structure comprises: the seat tube comprises a seat tube body, a first limiting structure and a second limiting structure, wherein the edges of the two ends of the seat tube body are respectively formed along the circumferential direction, the second limiting structure is connected with one end of the first limiting structure, and meanwhile, the second limiting structure is connected with the seat tube body.

In the embodiment of the utility model, the section of the second limiting structure is in a shape like a Chinese character 'ji', so that one end of the second limiting structure is connected with the pipe wall of the seat pipe body, and the other end of the second limiting structure is connected with one end of the first limiting structure.

In the embodiment of the utility model, the cross section of the first limiting structure is in an L-shaped flanging structure, so that the axial section of the first limiting structure is connected with the other end of the second limiting structure, the radial section of the first limiting structure extends to the outer side of the second limiting structure, and the two surfaces of the wallboard are respectively attached to the radial section of the first limiting structure and the outer side surface of the second limiting structure.

In the embodiment of the utility model, when the seat tube body is a circular tubular body, the first limiting structure is a circular ring structure with an L-shaped section.

In the embodiment of the utility model, when the seat tube body is a first special tube of a non-circular tubular body, an anti-cracking groove is formed at the corner structure of the first special tube, so that the first limit structure of the first special tube is composed of a plurality of limit flanges with L-shaped sections.

In the embodiment of the utility model, the first special-shaped tube comprises a rectangular tube, a square tube and a D-shaped tube.

In the embodiment of the utility model, when the seat tube body is a second special tube of a non-circular tubular body, the first limit structure of the second special tube is an annular structure with an L-shaped section.

In the embodiment of the utility model, the second special-shaped tube comprises an elliptical tube and a waist-shaped tube.

In the embodiment of the utility model, an arc transition section is arranged between the axial section and the radial section of the first limiting structure, the included angle of the arc transition section is arranged at the joint of the axial section and the outer side surface of the second limiting structure, the included angle of the arc transition section is R, and the radius range of the R angle is 1-1.5mm.

In the embodiment of the utility model, the seat tube body, the second limiting structure and the first limiting structure are of an integrated structure and are coaxially arranged.

The utility model adopts the technical proposal, which has the following beneficial effects:

(1) The utility model is provided with the limiting structure, the second limiting structure and the first limiting structure form a bending gap, so that the wallboard with the assembly hole is convenient for the sleeving and assembly of the wallboard on the pipe body for the seat, the axial movement of the pipe body for the seat is limited by the joint of the second limiting structure and the first limiting structure and the two faces of the wallboard, and the radial movement of the pipe body for the seat is limited by the joint of the hole wall of the assembly hole and the surface of the pipe body for the seat, thereby achieving the aim of limiting and ensuring the reliable connection of the pipe body for the seat and the wallboard.

(2) The utility model has the advantages that the flower-shaped holes are formed, the material can be extruded into the flower-shaped holes when the seat tube body of the round tube is screwed and riveted, the contact area between the seat tube body and the wallboard is increased, the connection reliability is improved, meanwhile, the rotation of the seat tube body relative to the wallboard is limited by the jogging of the flower-shaped holes and the material, the anti-rotation aim is achieved, and the reliable connection between the seat tube body of the round tube and the wallboard is further ensured.

(3) According to the utility model, the seat tube body with the special-shaped structure is adopted, and the assembly holes on the wall plates are of the special-shaped structure matched with the section of the seat tube body, so that the rotation of the seat tube body relative to the wall plates is limited by the special-shaped structure, the anti-rotation purpose is achieved, and the reliable connection between the seat tube body of the special-shaped tube and the wall plates is further ensured; and meanwhile, the first limit structure is prevented from cracking in the process of overturning through the slotting design of the anti-cracking slot, so that the structural strength of the first limit structure is ensured.

(4) The utility model has the advantages that the wall plate can be reliably limited on the seat tube body without falling off due to the first limiting structure, the square sheet is not required to be welded, the square sheet and the wall plate are not required to be connected through bolts, the whole assembly process is more environment-friendly, the process is simpler, the parts are fewer, the weight is lighter, and the production beat and the production cost are favorably controlled.

Drawings

FIG. 1 is an assembled schematic view of a tube anti-rotation limit assembly for a seat in accordance with the present utility model;

FIG. 2 is a partial schematic view of the assembly of FIG. 1;

FIG. 3 is a partial cross-sectional block diagram of FIG. 2;

FIG. 4 is a schematic cross-sectional view of a limiting structure in the tube anti-rotation limiting assembly for a seat of the present utility model;

FIG. 5 is a front view of a wall plate (seat tube body for round tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 6 is a schematic view showing the assembly of a seat tube body (the seat tube body is a circular tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 7 is an assembled cross-sectional view of a seat tube body (the seat tube body is a round tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 8 is a view showing an assembly process of a seat tube body (the seat tube body is a circular tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 9 is a schematic structural view of a first limiting structure in the seat tube anti-rotation limiting assembly of the present utility model (the seat tube body is a square tube);

FIG. 10 is a cross-sectional view of a seat tube body (the seat tube body is an oval tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 11 is a cross-sectional view of a seat tube body (the seat tube body is a lumbar tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 12 is a cross-sectional view of a seat tube body (the seat tube body is a rectangular tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 13 is a cross-sectional view of a seat tube body (the seat tube body is a square tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 14 is a cross-sectional view of a seat tube body (the seat tube body is a D-tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 15 is a schematic view of a split groove of a seat tube body (the seat tube body is a rectangular tube) in a seat tube anti-rotation limit assembly of the present utility model;

FIG. 16 is a view showing an assembly process of a seat tube body (the seat tube body is a square tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 17 is a schematic view of the structure of the wall plate in the seat tube anti-rotation limiting assembly of the present utility model (seat tube body for square tube);

FIG. 18 is a schematic view of the seat tube body (the seat tube body is a waist tube) in the seat tube anti-rotation limit assembly of the present utility model;

FIG. 19 is a schematic view showing the turning of the seat tube body (the seat tube body is a D-tube) in the seat tube anti-rotation limit assembly of the present utility model;

Fig. 20 is a schematic view showing the turning over of the seat tube body (the seat tube body is an oval tube) in the seat tube anti-rotation limiting assembly of the present utility model.

The correspondence of the reference numerals with the components is as follows:

A seat tube body 1; a first limit structure 101; limit flanges 1011; an anti-cracking groove 1012; an axial section 1013; radial segment 1014; a second limit structure 102; an outer side 1021; a U-shaped structure 103; a wall plate 2; a fitting hole 201; flower shaped aperture 202.

Detailed Description

In order to facilitate the understanding of the present utility model, the following description is provided with reference to the drawings and examples.

Referring to fig. 1 and fig. 2, a seat tube anti-rotation limiting assembly includes a seat tube body 1 and a limiting structure, wherein a pair of limiting structures are symmetrically formed at two ends of the seat tube body 1, so that two ends of the seat tube body 1 are respectively fixed on two wall plates 2 through the limiting structures.

The pipe body 1 and the wallboard 2 for the seat are provided with a simple and quick connection mode through the limiting structure, a traditional square sheet welding and screwing mode is not needed, the assembly process is more environment-friendly, the structure is simpler, the number of parts is reduced, the quality is reduced, the production cost is reduced, and the production beat is improved. Meanwhile, the pipe body 1 for the seat is provided with an axial limiting function through the limiting structure, and an anti-rotation function is provided between the pipe body 1 for the seat and the wall plate 2, so that the connection reliability between the pipe body 1 for the seat and the wall plate 2 is ensured.

Referring to fig. 7, 9 and 17, the seat tube body 1 is a circular tubular body (as shown in fig. 7) or a non-circular tubular body (as shown in fig. 10-14); the wall plate 2 is formed with an attachment hole 201 through which the seat tube body 1 passes, and the wall plate 2 is fitted to the seat tube body 1 through the attachment hole 201.

Through the setting of mounting hole 201, be convenient for with on wallboard 2 suit seat is with pipe body 1, the shape adjustment of pipe body 1 cross-section is used to accessible mounting hole 201 and seat, adopts the seat of non-circular tubular body promptly with pipe body 1 and the corresponding mounting hole 201 of matching the shape, makes between wallboard 2 and the seat with pipe body 1 match the chucking, avoids relative rotation, reaches anti-rotation's purpose. Meanwhile, after the wallboard 2 is sleeved, the wallboard 2 is prevented from moving along the radial direction of the seat tube body 1 through a limiting structure, so that the purpose of radial limiting is achieved. The shape and size of the fitting hole 201 are determined according to the sectional shape and size of the seat tube body 1.

Referring to fig. 5 to 7, when the seat tube body 1 is a circular tubular body, i.e., a circular tube, a flower-shaped hole 202 is formed at the edge of the fitting hole 201, and the material of the seat tube body 1 is extruded into the flower-shaped hole 202.

Because the seat tube body 1 is a circular tube, there may be relative rotation between the seat tube body 1 and the wall plate 2, and therefore, by the arrangement in the flower-shaped hole 202, the seat tube body 1 can squeeze the material of the seat tube body 1 into the flower-shaped hole 202 in the spin riveting process, thereby increasing the contact area between the seat tube body 1 and the wall plate 2, improving the connection reliability of the seat tube body 1 and the wall plate 2, and simultaneously, utilizing the mutual jogging between the flower-shaped hole 202 and the squeezed material, the relative rotation between the seat tube body 1 and the wall plate 2 can be limited, and the anti-rotation function is achieved.

Referring to fig. 3 and fig. 4, the limiting structure includes a first limiting structure 101 and a second limiting structure 102; the two ends of the seat tube body 1 are respectively provided with a first limit structure 101 along the circumferential direction, the two ends of the seat tube body 1 are respectively provided with a second limit structure 102 along the circumferential direction, the second limit structure 102 is connected with one end of the first limit structure 101 and is connected with the seat tube body 1, and the two ends of the seat tube body 1 are provided with limit structures.

The second limiting structure 102 can be directly formed at the end part of the seat tube body 1 by adopting processes such as tube expansion and the like, the first limiting structure 101 can be directly formed at the end part of the seat tube body 1 by adopting processes such as spin riveting, punching riveting, flanging and the like, the processing process is simple, extra parts such as square sheets and bolts are not required, the environment is protected, the number of parts is reduced, and the assembly process is simplified.

The limit structures at the two ends of the seat tube body 1 are symmetrically arranged and have the same structure, and only the limit structure at one end of the seat tube body 1 is shown in the drawing.

Referring to fig. 3 and fig. 4, the cross section of the second limiting structure 102 is in a shape like a Chinese character 'ji', so that one end of the second limiting structure 102 is connected with the wall of the seat tube body 1, and the other end of the second limiting structure 102 is connected with one end of the first limiting structure 101.

The second limiting structure 102 is formed by a tube expanding process in the prior art, and the height and thickness of the second limiting structure 102 can be adaptively adjusted according to actual installation requirements, so that a limiting function along the axial direction of the seat tube body 1 can be provided for the wall plate 2.

Referring to fig. 3 and fig. 4, the cross section of the first limiting structure 101 is in an L-shaped flange structure, so that an axial section 1013 of the first limiting structure 101 (an end of the first limiting structure 101 axially disposed along the seat tube body 1 is an axial section, an end of the first limiting structure 101 radially disposed along the seat tube body 1 is a radial section) is connected to the other end of the second limiting structure 102, the radial section 1014 of the first limiting structure 101 extends to the outside of the second limiting structure 102 (an outer side of the second limiting structure 102 away from the center of the seat tube body 1 is an outer side, and an inner side of the second limiting structure 102 near the center of the seat tube body 1 is an inner side), so that the radial sections 1014 of the first limiting structure 101 and the outer side 1021 of the second limiting structure 102 are respectively attached to two surfaces of the wall plate 2.

The first limiting structure 101 can be formed by adopting processes of turning, spin riveting, flanging and the like in the prior art according to the sectional shapes of different seat tube bodies 1, and after the wall plate 2 is assembled on the seat tube body 1, the seat tube body 1 is turned over to form the first limiting structure 101, and the wall plate 2 is wrapped in the U-shaped structure 103 between the radial section 1014 of the first limiting structure 101 and the outer side 1021 of the second limiting structure 102. The width of the U-shaped structure 103 formed by the radial sections 1014 and the outer side 1021 corresponds to the thickness of the wall plate 2, so that the U-shaped structure 103 formed by the outer side 1021 and the radial sections 1014 provides an effective stop for the wall plate 2 in the axial direction of the seat tube body 1.

The height of the first stopper 101 is substantially equal to the height of the second stopper 102, and the stopper function in the axial direction of the seat tube body 1 can be provided to the wall plate 2.

Referring to fig. 1 to 3, when the seat tube body 1 is a circular tube body, i.e. a round tube, the first limiting structure 101 is a circular ring structure with an L-shaped cross section.

When the seat tube body 1 of the round tube is turned into the first limit structure 101, the turning and riveting process can be adopted for turning and forming, and the first limit structure 101 is formed into a circular ring structure and can be used for limiting the axial and radial displacement of the wall plate 2 along the seat tube body 1.

Referring to fig. 9 and 19, when the seat tube body 1 is a first shaped tube of a non-circular tubular body, an anti-cracking groove 1012 is formed at a corner of the first shaped tube, so that the first limiting structure 101 of the first shaped tube is formed by a plurality of limiting flanges 1011 with L-shaped cross sections.

When the first special pipe is turned, if a corner structure (comprising a corner structure with a smooth transition section) between the straight edge and between the straight edge and the arc edge exists in the first special pipe, the corner structure has a smaller angle (usually not more than 90 degrees), and the corner structure is easy to crack in the turning process, so that an anti-cracking groove 1012 is formed at the corner, and the depth of the anti-cracking groove 1012 can be determined according to the turning size of the limit turning 1011 and is used for preventing the turning from cracking. For the first special-shaped pipes with different shapes, the shapes, angles and the number of the corner structures are correspondingly different, the cracking risks of the corner structures possibly existing in the processes of spin riveting, punching turning and the like can be met, and the anti-cracking grooves 1012 are arranged at the corresponding corner structures in an adaptive manner so as to ensure the structural strength and durability of the formed first limiting structure 101.

Due to the arrangement of the anti-cracking grooves 1012, the annular first limiting structure 101 is broken at the notch to form a plurality of limiting flanges 1011, and the number of the limiting flanges 1011 is determined according to the number of the anti-cracking grooves 1012, namely a square pipe seat pipe body 1 shown in fig. 9 and a D-pipe seat pipe body 1 shown in fig. 19.

The first special-shaped tube comprises a rectangular tube (shown in figure 12), a square tube (shown in figure 13), a D-shaped tube (shown in figure 14), a regular hexagon tube and the like. There are four straight flange and 90 corner structures of straight flange in rectangular pipe and the square pipe, regular hexagon pipe has two straight flange contained angle 120 corner structures, exists straight flange and arc limit corner structure in the D type pipe, probably has the fracture risk in the turn-ups process, can set up anti-cracking groove 1012 at four corners of rectangular pipe and square pipe and two corners of D type pipe.

Fig. 12-14 only show the cross-sectional forms of three first special-shaped tubes commonly used in actual production, and the first special-shaped tubes can be set into other special-shaped cross-sectional structures according to actual requirements, and are not repeated here.

Referring to fig. 18 and 20, when the seat tube body 1 is a second shaped tube of a non-circular tubular body, the first limiting structure 101 of the second shaped tube is an annular structure with an L-shaped cross section.

The second special-shaped tube comprises an elliptical tube (shown in figure 10), a waist-shaped tube (shown in figure 11) and the like.

The oval tube does not contain a corner structure, the angle of the corner structure between the middle straight edge and the arc edge of the waist-shaped tube is larger (usually larger than 90 degrees), the second special-shaped tube does not crack in the flanging process, an anti-cracking groove 1012 is not arranged, and the end part of the tube body 1 for the seat can be directly subjected to flanging forming by adopting processes such as spin riveting, punching riveting and overturning, so that a first limiting structure 101 is formed.

Fig. 10 and 11 only show the cross-sectional forms of two second special-shaped tubes commonly used in actual production, and the second special-shaped tubes can be set into other special-shaped cross-sectional structures according to actual requirements, and are not repeated here.

Referring to fig. 4, an arc transition section is disposed between the axial section 1013 and the radial section 1014 of the first limiting structure 101, an included angle of the arc transition section is R, an arc transition section is disposed at a connection portion between the axial section 1013 of the first limiting structure 101 and the outer side 1021 of the second limiting structure 102, the included angle of the arc transition section is R, and a radius range of the R angle is 1-1.5mm.

The smaller the radius of the R angle is, the higher the fitting degree between the hole wall of the fitting hole 201 and the axial section 1013 of the first limit structure 101 is, thereby ensuring the fitting reliability between the wall plate 2 and the seat tube body 1.

Because the process is limited, a certain radian is unavoidable in the corner position during flanging, and the corner position cannot be completely attached to the hole wall at the position of the assembly hole 201 of the wall plate 2, so that the radius of the R angle is as small as possible to improve the connection strength.

The seat tube body 1, the second limiting structure 102 and the first limiting structure 101 are integrally and coaxially arranged.

Referring to fig. 1 to 20, the manufacturing process of the present utility model includes:

The second limiting structure 102 is formed at the position, close to the end part, of the seat tube body 1 through a tube expanding process, the second limiting structure 102 and the seat tube body 1 are coaxially arranged, and the section of the second limiting structure 102 is shaped like a Chinese character 'ji'. A certain distance is reserved between the second limiting structure 102 and the end edge of the seat tube body 1, and the second limiting structure is used for processing the first limiting structure 101.

Referring to fig. 8, if the seat tube body 1 is a circular tube body, i.e., a round tube, the wall plate 2 with the circular assembly hole 201 and the flower hole 202 is sleeved on the seat tube body 1, and one surface of the wall plate 2 is attached to the outer side 1021 of the second limiting structure 102. The end part of the seat tube body 1 is turned up to form a circular ring-shaped structure with an L-shaped section, namely a first limit structure 101 through a spin riveting process, and the first limit structure 101 is attached to the other surface of the wall plate 2. When the end of the seat tube body 1 is turned by spin riveting, the material of the seat tube body 1 is pushed into the flower hole 202.

The second limiting structure 102 and the first limiting structure 101 provide axial limiting for the seat tube body 1, and meanwhile, the seat tube body 1 is provided with a rotation preventing function through materials filled in the flower-shaped holes 202, so that fixed plug-in connection between the seat tube body 1 and the wall plate 2 is ensured.

Referring to fig. 16, if the seat tube body 1 is a first special tube of a non-circular tubular body, i.e. a rectangular tube, a square tube or a D-shaped tube, the wall plate 2 with the fitting hole 201 of the matched special-shaped structure is sleeved on the seat tube body 1, and one surface of the wall plate 2 is attached to the outer side 1021 of the second limiting structure 102. An anti-cracking groove 1012 is formed in the corner structure of the first special pipe, the corner structure which does not exceed 90 degrees is prevented from cracking when the pipe is turned over, the end of the seat pipe body 1 is turned over through the turning over process to form a plurality of limit turned-over edges 1011 with L-shaped sections, and the limit turned-over edges 1011 are attached to the other surface of the wall plate 2.

The second limiting structure 102 and the limiting flange 1011 provide axial limiting for the pipe body 1 for the seat, and the pipe body 1 for the seat provides a rotation preventing function through the matching sleeve joint of the assembly hole 201 of the special-shaped structure and the first special-shaped pipe, thereby ensuring the fixed plug-in connection between the pipe body 1 for the seat and the wallboard 2.

If the seat tube body 1 is the second special tube of the non-circular tubular body, i.e. the oval tube or the waist tube, the wall plate 2 with the matched special-shaped structure assembly holes 201 is sleeved on the seat tube body 1, and one surface of the wall plate 2 is attached to the outer side surface 1021 of the second limiting structure 102. The end of the seat tube body 1 is turned over by an over-turning process to form an annular structure with an L-shaped section, namely a first limit structure 101, and the first limit structure 101 is attached to the other surface of the wall plate 2.

The second limiting structure 102 and the first limiting structure 101 provide axial limiting for the pipe body 1 for the seat, and the pipe body 1 for the seat is provided with a rotation preventing function through matching and sleeving of the assembly holes 201 of the special-shaped structures and the second special-shaped pipes, so that fixed splicing between the pipe body 1 for the seat and the wall plate 2 is ensured.

The present utility model has been described in detail with reference to the drawings and embodiments, and one skilled in the art can make various modifications to the utility model based on the above description. Accordingly, certain details of the illustrated embodiments are not to be taken as limiting the utility model, which is defined by the appended claims.

Claims (12)

1. The seat tube anti-rotation limiting assembly is characterized by comprising a seat tube body and limiting structures, wherein the limiting structures are formed at two ends of the seat tube body, so that the two ends of the seat tube body are respectively fixed on a wallboard through the limiting structures; the limit structure comprises: the two ends of the seat tube body are respectively provided with a first limiting structure formed along the circumferential direction at the edges of the two ends of the seat tube body and a second limiting structure formed along the circumferential direction at the two ends of the seat tube body; the second limit structure is connected with one end of the first limit structure and is connected with the seat tube body.

2. The seat tube anti-rotation limit assembly according to claim 1, wherein the seat tube body is a circular tubular body or a non-circular tubular body; the wall plate is provided with an assembly hole for the pipe body for the seat to pass through, so that the wall plate is sleeved on the pipe body for the seat through the assembly hole.

3. The seat tube rotation preventing limit assembly according to claim 2, wherein when the seat tube body is a circular tubular body, a flower-shaped hole is formed at the edge of the assembly hole, and the material of the seat tube body is extruded into the flower-shaped hole.

4. The seat tube anti-rotation limiting assembly according to claim 1, wherein the section of the second limiting structure is in a shape like a Chinese character 'ji', so that one end of the second limiting structure is connected with the tube wall of the seat tube body, and the other end of the second limiting structure is connected with one end of the first limiting structure.

5. The seat tube anti-rotation limiting assembly according to claim 1, wherein the cross section of the first limiting structure is in an L-shaped flanging structure, so that the axial section of the first limiting structure is connected with the other end of the second limiting structure, the radial section of the first limiting structure extends to the outer side of the second limiting structure, and two surfaces of the wall plate are respectively attached to the radial section of the first limiting structure and the outer side surface of the second limiting structure.

6. The seat tube anti-rotation limit assembly according to claim 1 or 5, wherein when the seat tube body is a circular tubular body, the first limit structure is an annular structure with an L-shaped cross section.

7. The seat tube rotation-preventing and limiting assembly according to claim 1 or 5, wherein when the seat tube body is a first special tube of a non-circular tubular body, an anti-cracking groove is formed at a corner structure of the first special tube, so that the first limiting structure of the first special tube is formed by a plurality of limiting flanges with L-shaped cross sections.

8. The seat tube anti-rotation limiting assembly according to claim 7, wherein the first special tube comprises a rectangular tube, an orthosquare tube, an orthohexagonal tube, and a D-shaped tube.

9. The seat tube rotation preventing and limiting assembly according to claim 1 or 5, wherein when the seat tube body is a second special tube of a non-circular tubular body, the first limiting structure of the second special tube is an annular structure with an L-shaped section.

10. The seat tube anti-rotation limiting assembly of claim 9, wherein the second shaped tube comprises an oval tube or a waist tube.

11. The seat tube anti-rotation limiting assembly according to claim 5, wherein an arc transition section is arranged between the axial section and the radial section of the first limiting structure, an included angle of the arc transition section is R, an arc transition section is arranged at the joint of the axial section of the first limiting structure and the outer side surface of the second limiting structure, the included angle of the arc transition section is R, and the radius range of the R angle is 1-1.5mm.

12. The seat tube anti-rotation limit assembly according to claim 1 or 5, wherein the seat tube body, the second limit structure and the first limit structure are integrally formed and coaxially arranged.