Pipe assembly, frame and spinning mechanism

Abstract

The utility model belongs to the technical field of electric bicycles, and discloses a pipe assembly, a bicycle frame and a spinning mechanism. The front tube and the lower tube which are integrally formed are cut to form a tube assembly, and the battery cover in the tube assembly is obtained through cutting. The frame includes a motor seat and the tube assembly. The spinning mechanism is used for conducting spinning on the plate in the integrated forming process. The front pipe and the lower pipe can be integrally formed through the pipe assembly, the frame and the spinning mechanism, the overall strength of a product is improved, surfacing marks generated by welding are avoided, the product quality is guaranteed, and the productivity is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electric bicycles, in particular to a pipe assembly, a frame and a spinning mechanism. Background Art

[0002] The frame is an important part of an electric bicycle. Its manufacturing process includes molding, welding, and subsequent machining. The welding process is complex and requires more welding and correction jigs. It is easy to deform after welding, the structure is unstable, and the strength is low. In addition, both manpower and material resources require high costs. Especially for electric bicycles, the wall thickness of the product is thicker than that of conventional bicycles, making it more difficult to make the product appearance smooth. After welding, the surfacing marks of the weld are particularly obvious. At the same time, due to the inconsistent welding level of each technician, the quality is unstable and the production capacity is low. Among them, the overlap of the front tube and the lower tube is particularly complicated, and it is difficult to guarantee the welding and appearance quality. In addition, the battery usually needs to be installed at the position of the lower tube, and the battery cover needs to be manufactured separately, wasting raw materials.

[0003] Therefore, it is urgent to design a pipe assembly, a frame and a spinning mechanism to solve the above problems. Utility Model Content

[0004] The first object of the utility model is to provide a pipe assembly, which is an integrally formed structure, has higher strength, beautifies the appearance, and can save the use of materials.

[0005] The second object of the utility model is to provide a frame with improved overall strength, reduced welding positions and more beautiful appearance.

[0006] The third purpose of the utility model is to provide a spinning mechanism that can spin the sheet material into a first intermediate, and cooperate with other molds to achieve one-piece forming of the front tube and the lower tube, thereby improving the overall strength of the product, avoiding surfacing marks caused by welding, and ensuring product quality.

[0007] To achieve this purpose, the utility model adopts the following technical solutions:

[0008] A tube assembly, the tube assembly comprising a battery and an integrally formed front tube and a down tube, the front tube being located at one end of the down tube, and the down tube comprising:

[0009] A main body, wherein a receiving cavity is formed inside the main body, and a placement opening is provided on one side of the main body;

[0010] A battery cover, separated from the main body by cutting, the battery cover can open or close the placement opening;

[0011] The battery can be placed into the accommodating cavity from the placement opening.

[0012] As an optional solution, the battery and the battery cover are fixed by gluing or screwing.

[0013] As an optional solution, the tube assembly further comprises a retaining spring, and both ends of the battery cover are provided with the retaining springs, and each of the retaining springs can be engaged with the body at the placement opening.

[0014] Frame, including:

[0015] The above-mentioned pipe assembly;

[0016] The motor seat is connected to one end of the lower tube away from the front tube.

[0017] A spinning mechanism is used to form the above-mentioned pipe assembly, and the above-mentioned spinning mechanism comprises:

[0018] A main mold and a tail top, wherein the main mold and the tail top are configured to be able to approach each other to clamp the sheet material and drive the sheet material to rotate;

[0019] The rotating wheel can abut against the plate material and feed along the main mold in a direction away from the tail top, so that the first intermediate body fits the outer shape of the main mold.

[0020] As an optional solution, the above main model includes:

[0021] Die base;

[0022] A mounting member connected to one end of the mold base;

[0023] A plurality of sliders are arranged in a ring shape along the circumference of the above-mentioned mounting member, one of the above-mentioned sliders and the above-mentioned mounting member is provided with a slide groove, and the other of the above-mentioned sliders and the above-mentioned slide rails are provided, the above-mentioned slide grooves and the above-mentioned slide rails are arranged in a one-to-one correspondence and both extend along the axial direction of the above-mentioned mounting member, and the above-mentioned slide grooves and the corresponding above-mentioned slide rails are slidably matched.

[0024] As an optional scheme, the plurality of the above-mentioned sliders are divided into first sliders and second sliders, and the above-mentioned first sliders and the above-mentioned second sliders are alternately arranged in sequence. The above-mentioned first slider can be radially moved out from between two adjacent second sliders, and the projections of the above-mentioned first slider and the above-mentioned second slider after translation can fall within the axial projection range of the above-mentioned mold base.

[0025] As an optional solution, the angle between two adjacent outer surfaces of the first sliding block and the second sliding block is 8°-12°.

[0026] As an optional solution, the size of the slide rail gradually decreases from its free end to the connecting end.

[0027] As an optional solution, the main mold is provided with a through hole along its axial direction, and the through hole is connected to the high-pressure gas generating device.

[0028] The beneficial effects of the utility model are:

[0029] The utility model also provides a tube assembly, which is an integrally formed structure with higher strength, and the battery cover is formed by cutting, which can save the use of materials.

[0030] The utility model also provides a vehicle frame, the overall strength of which is improved, the welding positions are reduced, and the appearance is more beautiful.

[0031] The utility model also provides a spinning mechanism, in which the sheet material is first placed between the main mold and the tail top and clamped by the two, and as the main mold and the tail top rotate, the sheet material is driven to rotate, and at the same time, the rotating wheel is fed toward the main mold, the sheet material undergoes plastic deformation, and the first intermediate after spinning is consistent with the appearance of the main mold. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of various states of the pipe fitting provided by the embodiment of the utility model during the molding process;

[0033] Figure 2 It is a flow chart of the steps of forming the front tube and the down tube provided by an embodiment of the utility model;

[0034] Figure 3 It is a structural schematic diagram of the spinning mechanism provided by the embodiment of the utility model before and after spinning;

[0035] Figure 4 It is a schematic structural diagram of a mounting member and a plurality of sliding blocks provided in an embodiment of the utility model in an axial perspective;

[0036] Figure 5 It is a detailed flow chart of step S30 provided in an embodiment of the utility model;

[0037] Figure 6 is an exploded view of a pipe assembly provided by an embodiment of the utility model;

[0038] Figure 7 It is a structural schematic diagram of a vehicle frame provided by an embodiment of the utility model.

[0039] In the figure:

[0040] 11. sheet material; 12. first intermediate; 13. second intermediate; 131. first preformed intermediate; 132. second preformed intermediate; 133. third preformed intermediate; 14. third intermediate;

[0041] 20. tube assembly; 21. front tube; 22. lower tube; 221. body; 2211. placement port; 222. battery cover; 23. battery; 24. retaining spring;

[0042] 30. Motor seat; 40. Middle tube; 50. Upper fork; 60. Lower fork; 70. Spinning mechanism; 71. Main mold; 711. Through hole; 712. Mold seat; 713. Mounting part; 7131. Slide rail; 714. Slider; 7141. Slide groove; 7142. First slider; 7143. Second slider; 72. Tail top; 73. Rotating wheel. DETAILED DESCRIPTION

[0043] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0044] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0046] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0047] This embodiment provides a pipe assembly 20, such as Figure 6As shown, the tube assembly 20 includes a battery 23 and an integrally formed front tube 21 and a lower tube 22. The front tube 21 is located at one end of the lower tube 22. The lower tube 22 includes a body 221 and a battery cover 222. A receiving cavity is formed inside the body 221, and a placement opening 2211 is provided on one side of the body 221. The battery cover 222 is separated from the body by cutting, and the placement opening 2211 can be opened or closed. The battery 23 can be placed in the receiving cavity from the placement opening 2211. Through the above arrangement, the integrally formed front tube 21 and lower tube 22 reduce the steps of connecting the two by welding, and make the appearance more beautiful. The lower tube 22 is directly cut along the shape of the placement opening 2211 to form the body 221 and the battery cover 222. That is, the battery cover 222 does not need to be manufactured separately, but is directly produced by the cutting process, saving the use of materials.

[0048] Optionally, the battery 23 is fixed to the battery cover 222 by gluing or screwing. Through the above arrangement, it is convenient to install the battery 23. That is, after the battery cover 222 is buckled, the battery 23 is installed in the accommodating cavity at the same time.

[0049] Alternatively, if Figure 6 As shown, the tube assembly 20 further includes a clamping spring 24, and the two ends of the battery cover 222 are both installed with a clamping spring 24, and each clamping spring 24 can be clamped with the body 221 at the placement opening 2211. Through the above arrangement, when installing the battery cover 222, the two clamping springs 24 are compressed, and the battery cover 222 is placed at the placement opening 2211, and then the clamping spring 24 is loosened to achieve the rapid installation of the battery cover 222.

[0050] This embodiment also provides a frame, such as Figure 7 As shown, the frame includes a motor seat 30 and the above-mentioned pipe assembly 20; the motor seat 30 is connected to the end of the lower tube 22 away from the front tube 21. By using the above-mentioned pipe assembly 20, the overall strength of the frame is improved, the welding position is reduced, and the appearance is more beautiful.

[0051] Alternatively, if Figure 7 As shown, the frame further includes a middle tube 40, a seat fork 50 and a chain fork 60, one end of the middle tube 40 is connected to the motor seat 30 and extends in a direction away from the motor seat 30, one end of the seat fork 50 is connected to the end of the middle tube 40 away from the motor seat 30, one end of the chain fork 60 is connected to the motor seat 30, and the other ends of the seat fork 50 and the chain fork 60 are connected. It can be understood that the middle tube 40, the seat fork 50, the chain fork 60 and the motor seat 30 form a similar triangular structure, making the rear of the frame more stable and firm.

[0052] The following describes the steps of forming the lower tube and the front tube, wherein the front tube 21 and the lower tube 22 are the front tube 21 and the lower tube 22 of the electric bicycle. This forming step can realize the integral forming of the front tube 21 and the lower tube 22, avoid the appearance problems caused by welding and improve the connection strength. Figure 1 and Figure 2 As shown, the steps of forming the front tube and the down tube include:

[0053] S10: unfolding the front tube 21 and the lower tube 22 to be formed into a blank according to the outer shape of the blank, and cutting the plate into the plate 11 according to the unfolded shape;

[0054] S20: Spinning, using the spinning mechanism 70 to apply pressure to the rotating sheet material 11, so that the sheet material 11 is formed into a first intermediate body 12, the first end of the first intermediate body 12 is open, and the diameter of the second end of the first intermediate body 12 is larger than the diameter of the first end;

[0055] S30: preforming, using a preforming mold to flatten the first intermediate 12 so that the first intermediate 12 is formed into a second intermediate 13;

[0056] S40: Thermoplastic molding, placing the second intermediate body 13 into a thermoplastic molding mold cavity, and injecting compressed high-pressure air into the first end to mold the second intermediate body 13 into a third intermediate body 14;

[0057] S50 : cutting the third intermediate body 14 to form the tube assembly 20 .

[0058] The above-mentioned forming step of the front tube and the down tube is achieved by spinning the sheet material 11. During the spinning process, the sheet material 11 undergoes continuous local plastic deformation to form the required hollow gourd shape with variable cross-section (outer diameter size at different positions) and variable wall thickness, one end closed and the other end open, so that the first intermediate body 12 has the prototype of the front tube 21 and the down tube 22. The first intermediate body 12 is pre-formed, thermoplastic formed and cut, so that the one-piece forming of the front tube 21 and the down tube 22 of the electric bicycle is achieved, avoiding the problem of insufficient structural strength caused by welding the front tube 21 and the down tube 22, or the obvious impact of weld marks on the appearance. At the same time, this forming step avoids the problem of poor product consistency caused by welding, does not require manual operation, improves production capacity, and avoids the situation where different operators process products with large differences.

[0059] Preferably, the spinning method is divided into heating spinning and ordinary spinning, and heating spinning is divided into high-frequency heating and flame heating, wherein heating spinning can increase the ductility of the sheet 11, making the sheet 11 easier to deform. Specifically, when heating spinning is adopted, the heating temperature is T1, 260℃≤T1≤300℃, and adding high temperature resistant lubricating oil is equivalent to surface lubrication annealing: eliminating or reducing the increase in internal stress of the pipe caused by spinning, and improving the subsequent elongation of the pipe fittings for easy molding.

[0060] Preferably, after spinning, the first intermediate 12 is removed and placed in an annealing furnace for annealing at 420°C for 3 hours, then cooled to 260°C at a rate of 50°C / hour, and then air-cooled. This can further release the internal stress concentration of the pipe caused by spinning, which is beneficial to subsequent deformation operations.

[0061] Preferably, an operation can be performed between S20 and S30: performing hemp wheel polishing on the first intermediate body 12. Through the above arrangement, the finish of the exterior of the semi-finished product can be increased.

[0062] This embodiment also provides a spinning mechanism 70, which is used to integrally form the front tube 21 and the lower tube 22. Figure 3 and Figure 4 As shown, the spinning mechanism 70 includes a main mold 71, a tail top 72 and a rotating wheel 73. The main mold 71 and the tail top 72 are configured to be close to each other to clamp the sheet 11 and drive the sheet 11 to rotate; the rotating wheel 73 can abut against the sheet 11 and feed in the direction of the main mold 71 away from the tail top 72, so that the first intermediate 12 fits the shape of the main mold 71. Through the above arrangement, the sheet 11 is first placed between the main mold 71 and the tail top 72 and clamped by the two. As the main mold 71 and the tail top 72 rotate, the sheet 11 is driven to rotate. At the same time, the rotating wheel 73 is fed in the direction of the main mold 71, and the sheet 11 is plastically deformed. The first intermediate 12 after spinning is consistent with the shape of the main mold 71.

[0063] Optionally, the main mold 71 has a "gourd-shaped" shape, with the large end serving as the prototype of the front tube 21, which is conducive to the later molding of the front tube 21, and the small end extending in a straight line direction and serving as the prototype of the lower tube 22. Adaptively, the rotating wheel 73 will also change its radial position when spinning the large end while feeding axially, so as to adapt to the change of the radius of the cross section of each part of the main mold 71.

[0064] In this embodiment, the plate 11 is circular. In other embodiments, the plate 11 can also be unfolded into other suitable shapes by means of software simulation, etc., which is not limited here.

[0065] Preferably, in order to realize demoulding of the first intermediate body 12 from the main mold 71, see Figure 3 and Figure 4The main mold 71 includes a mold base 712, a mounting member 713 and a plurality of sliders 714. The mounting member 713 is connected to one end of the mold base 712. The plurality of sliders 714 are arranged in an annular shape along the circumference of the mounting member 713. One of the sliders 714 and the mounting member 713 is provided with a slide groove 7141, and the other of the sliders 714 and the mounting member 713 is provided with a slide rail 7131. The slide grooves 7141 and the slide rails 7131 are arranged one by one and both extend along the axial direction of the mounting member 713. The slide grooves 7141 and the corresponding slide rails 7131 are slidably matched. Through the above arrangement, after the spinning is completed, the first intermediate 12 is moved in a direction away from the mold base 712. Due to the existence of the negative angle, the plurality of sliders 714 will move simultaneously with the first intermediate 12 and gradually separate from the mounting member 713. After the first intermediate 12 is removed, the plurality of sliders 714 can be taken out from the open end of the first intermediate 12, and then the plurality of sliders 714 can be slid and installed back on the mounting member 713 for the next spinning.

[0066] Among them, Figure 4 As shown, the plurality of sliders 714 are divided into a first slider 7142 and a second slider 7143, and the first slider 7142 and the second slider 7143 are alternately arranged in sequence, and the first slider 7142 can be moved out radially from between two adjacent second sliders 7143, and the projections of the first slider 7142 and the second slider 7143 after translation can both fall into the axial projection range of the mold base 712. That is, after the first intermediate body 12 is removed, the order of taking out the plurality of sliders 714 from the first intermediate body 12 is to first take out a plurality of first sliders 7142 in sequence, at this time, the plurality of second sliders 7143 are arranged at intervals, and then take out a plurality of second sliders 7143 in sequence, and at the same time, the projections of the first slider 7142 and the second slider 7143 after translation fall into the axial projection range of the mold base 712, so that the plurality of sliders 714 can be smoothly taken out from the opening end of the first intermediate body 12.

[0067] Alternatively, if Figure 4 As shown, the angle between the two adjacent outer surfaces of the first slider 7142 and the second slider 7143 is α, 8°≤α≤12°, preferably 10°. Through the above setting, it can be ensured that the first slider 7142 can be removed from between the two adjacent second sliders 7143.

[0068] Preferably, the size of the slide rail 7131 gradually decreases from its free end to the connection end. Through the above arrangement, the slide rail 7131 plays a role of radial limiting the slider 714, which can prevent the slider 714 from being separated from the mounting member 713, and ensure the installation stability of the slider 714. Figure 4As shown, the slide rail 7131 is arranged on the mounting member 713, and the slide groove 7141 is opened on the slider 714. In other embodiments, the slide rail 7131 can also be arranged on the slider 714, and the slide groove 7141 can be opened on the mounting member 713, which is not limited here.

[0069] In order to increase the demoulding speed of the first intermediate 12, preferably, as Figure 3 and Figure 4 As shown, the main mold 71 has a through hole 711 along its axial direction, and the through hole 711 is connected to the high-pressure gas generating device. Through the above arrangement, after the spinning is completed, high-pressure gas is introduced into the through hole 711, and the high-pressure gas acts on the first intermediate 12, making the demoulding action more labor-saving. Specifically, the through hole 711 is formed on the mold base 712 and the mounting member 713 to achieve the penetration of the through hole 711.

[0070] It should be noted that the mold base 712 is installed on an auxiliary device (not shown in the figure), and the auxiliary device can drive the mold base 712 to rotate. The high-pressure gas generating device can be installed on the auxiliary device, which will not be described in detail here.

[0071] The thickness of the sheet material 11 is T2, 4.5 mm < T2 ≤ 10 mm, and the wall thickness of the first intermediate body 12 is T3, 3.5 mm ≤ T3 ≤ 4.5 mm. The thickness of the sheet material 11 is adaptively changed according to the shape of the front tube 21 and the lower tube 22. The thickness of the opening end of the first intermediate body 12 is the thinnest, about 3.5 mm, the wall thickness of the large diameter end is about 4 mm, and the wall thickness of the part supported by the tail top 72 is about 4.5 mm.

[0072] Optionally, see again Figure 1 , Figure 2 and Figure 5 As shown, S30 includes:

[0073] S31: Flatten the first intermediate body 12 as a whole to form a first preformed intermediate body 131 ; in this step, the large end of the first intermediate body 12 is flattened to be closer to the final shape of the front tube 21 .

[0074] S32: The closed end of the first preformed intermediate body 131 is preformed to form a second preformed intermediate body 132 so that the shape of the closed end is closer to the front tube 21; in this step, the closed end is molded again to be closer to the shape of the front tube 21.

[0075] S33: bending the closed end of the second preformed intermediate body 132 to form a third preformed intermediate body 133, so that the closed end of the third preformed intermediate body 133 and the straight line segment of the third preformed intermediate body 133 form a preset angle;

[0076] Through the above arrangement, the first intermediate body 12 can be deformed gradually, thereby preventing the pipe from being cracked during the deformation process due to excessive deformation.

[0077] Preferably, surface treatment is performed after spinning. Specifically, the surface treatment steps include alkali stripping, pickling, film, saponification and water washing, wherein the role of alkali stripping is to remove grease and dirt on key surfaces to achieve the effect of purifying the surface. Pickling is based on sulfuric acid and hydrofluoric acid as the main components, which react with aluminum alloy to generate tiny bubbles to achieve the purpose of peeling off fine impurity particles on the surface. At the same time, under the action of surfactants, it also has a certain degreasing ability. The specific operation of the film is to soak the pipe fittings in the agent at a temperature of 70-80°C for 3-5 minutes, so that the inner and outer walls of the pipe fittings can achieve a coating lubrication effect, reduce the friction between the pipe fittings and the mold during the molding process, and avoid pulling or surface scratches on the pipe fittings. Among them, the temperature of the lubricant during the saponification process is 75°C-85°C, the pipe fittings are immersed for 5-7 minutes, and the pH is 8-10. The temperature of water washing is 70-90°C and the immersion time is 1-2 minutes.

[0078] Optionally, the cutting step includes cutting the appearance of the product and cutting the lower tube 22 .

[0079] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A pipe assembly, characterized in that The tube assembly comprises a battery (23) and an integrally formed front tube (21) and a down tube (22), wherein the front tube (21) is located at one end of the down tube (22), and the down tube (22) comprises: A body (221), wherein a receiving cavity is formed inside the body (221), and a placement opening (2211) is provided on one side of the body (221); A battery cover (222) is separated from the body (221) by cutting, and the battery cover (222) can open or close the placement opening (2211); The battery (23) can be placed into the accommodating cavity through the placement opening (2211).

2. The pipe assembly according to claim 1, characterized in that The battery (23) and the battery cover (222) are fixed by gluing or screwing.

3. The pipe assembly according to claim 1, characterized in that The tube assembly also includes a clamping spring (24), and the two ends of the battery cover (222) are both equipped with the clamping spring (24), and each of the clamping springs (24) can be clamped with the body (221) at the placement opening (2211).

4. A frame, characterized in that: include: The pipe assembly according to any one of claims 1 to 3; The motor seat (30) is connected to an end of the lower tube (22) away from the front tube (21).

5. Spinning mechanism, characterized in that: For forming the pipe assembly according to any one of claims 1 to 3, the spinning mechanism comprises: A main mold (71) and a tail top (72), wherein the main mold (71) and the tail top (72) are configured to be able to approach each other to clamp the sheet material (11) and drive the sheet material (11) to rotate; The rotating wheel (73) can abut against the plate material (11) and feed along the main mold (71) in a direction away from the tail top (72), so that the plate material (11) is deformed and fits the shape of the main mold (71).

6. The spinning mechanism according to claim 5, characterized in that: The main mold (71) comprises: Die base (712); A mounting member (713) connected to one end of the mold base (712); A plurality of sliders (714) are arranged in a ring shape along the circumference of the mounting member (713); a slide groove (7141) is provided in one of the sliders (714) and the mounting member (713); a slide rail (7131) is provided in the other of the sliders (714). The slide grooves (7141) and the slide rails (7131) are arranged in a one-to-one correspondence and both extend along the axial direction of the mounting member (713); the slide grooves (7141) and the corresponding slide rails (7131) are slidably matched.

7. The spinning mechanism according to claim 6, characterized in that: The plurality of sliders (714) are divided into a first slider (7142) and a second slider (7143), the first slider (7142) and the second slider (7143) are arranged alternately in sequence, the first slider (7142) can be moved radially out from between two adjacent second sliders (7143), and the projections of the first slider (7142) and the second slider (7143) after translation can fall within the axial projection range of the mold base (712).

8. The spinning mechanism according to claim 7, characterized in that: The included angle between the two adjacent outer surfaces of the first sliding block (7142) and the second sliding block (7143) is 8°-12°.

9. The spinning mechanism according to claim 6, characterized in that: The size of the slide rail (7131) gradually decreases from its free end to its connection end.

10. The spinning mechanism according to claim 6, characterized in that: The main mold (71) is provided with a through hole (711) along its axial direction, and the through hole (711) is connected to the high-pressure gas generating device.

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