CN118370919B - Balloon peripheral restraint device, balloon catheter and method for manufacturing the restraint device - Google Patents

Abstract

The application relates to the field of interventional medical instruments, and discloses a balloon peripheral restraint device, a balloon catheter and a method for manufacturing the restraint device, wherein the balloon peripheral restraint device is formed by weaving axial and circumferential weaving wires according to a preset mode, elasticity is given through heat setting, and the method can realize knitting to form the balloon periphery restraining device, and meanwhile, the formed balloon periphery restraining device is guaranteed to have good deformation characteristics so as to better restrain the deformation of the balloon.

Description

Balloon peripheral restraint device, balloon catheter and method for manufacturing the restraint device

Technical Field

The application relates to the field of interventional medical instruments, in particular to a balloon peripheral restraint device, a balloon catheter and a method for manufacturing the restraint device.

Background

Balloon catheters are a relatively common interventional instrument used in interventional hands. The basic structure is that a balloon which can be inflated is arranged on a catheter. In the interventional operation, the balloon is guided to the focus position along with the guide wire by the guide pipe, and an expansion medium is introduced into the balloon through a specific lumen in the guide pipe, so that the balloon is inflated to a preset degree, and the focus position of the blood vessel is fully expanded, so that the effect of improving the local stenosis of the blood vessel is achieved. The peripheral constraint type balloon dilation catheter technology is a novel interventional treatment technology in recent years, uniform and controllable vasodilation can be realized in the preparation and pre-dilation stages of the blood vessel, the elastic retraction of the blood vessel is effectively reduced, uncontrollable tearing and current limiting interlayer are avoided, and a vasodilation instrument with more clinical advantages is provided for doctors and patients.

The existing metal net is manufactured by taking nickel-titanium alloy pipes as blanks and performing multiple procedures such as cutting, grinding, heat setting, polishing and the like. Because the size of the metal net needs to be matched with the balloon, the metal net has the characteristics of small outer diameter and long length, and the problems of high processing difficulty, low yield and the like exist in actual production. Especially, when the metal net with long specification is subjected to electrochemical polishing, the defects of damage, uneven local thickness, notch, dirt generation and the like are more likely to occur.

Some of the related art, although proposing to form the above-mentioned metal mesh by wire braiding, for example CN216798465U suggests that the restraining means may be braided from resilient wire. However, such prior art often only proposes such a technical idea. However, how to form a mesh structure by weaving wires with extremely small diameters and meet the requirement of constraining the balloon at the same time is still a technical problem to be solved by those skilled in the art.

Disclosure of Invention

The application provides a balloon periphery restraint device, a balloon catheter and a method for manufacturing the restraint device, wherein the method can realize the weaving of the balloon periphery restraint device and ensure that the formed balloon periphery restraint device has better deformation characteristics so as to better restrain the deformation of the balloon.

To achieve the above object, a first aspect of the present application provides a balloon peripheral restraint device having at least an unstressed original state and a fully stretched state after stress, the balloon peripheral restraint device comprising one or more axial braided filaments, and a plurality of circumferential braided filaments, wherein in the original state: one or more axial braiding wires are bent around a plurality of fixed points to form a plurality of rows of axial elastic units, and the plurality of rows of axial elastic units are circumferentially distributed and connected through the circumferential braiding wires; each row of axial elastic units comprises a plurality of axially connected elastic subunits, and each elastic subunit comprises at least one bent first elastic part and connecting parts connected to two ends of the first elastic part; the circumferential braiding wires are correspondingly arranged at two end sides of each first elastic part, each circumferential braiding wire is continuously bent for one circle to form a plurality of bent second elastic parts, and the circumferential braiding wires are fixed to the axial braiding wires at each connecting part of the connecting parts and the first elastic parts;

In the fully extended state: the first elastic portion is stretched in an axial direction to a flat state, and the second elastic portion is stretched in a circumferential direction so that each circumferential braid wire is stretched to a circular ring shape.

According to some embodiments of the application, all the axial elastic units are formed by continuously bending one axial braided wire, and the head end and the tail end of the axial braided wire are fixedly connected with each other in a knotting manner.

According to some embodiments of the application, all of the connecting portions extend obliquely in the same direction, and/or,

The first elastic part is arranged to be of a structure formed by bending the axial braided wire around a certain point, and the second elastic part is arranged to be of a structure formed by bending the circumferential braided wire around a certain point.

According to some embodiments of the application, at each connection of the connection portion and the first elastic portion, the circumferential braid wires are wound around the axial braid wires at least one turn and knotted to be fixed to the axial braid wires.

According to some embodiments of the application, in the fully extended state, the first elastic portion has a length after being extended in the axial direction that is equal to a length after being extended in the circumferential direction of the second elastic portion.

According to some embodiments of the application, the axial braided wire and the circumferential braided wire are both provided as nitinol wires.

According to some embodiments of the application, the axial braided wires are formed with connection ends at both ends in the axial direction of the axial elastic units, the connection ends being disposed between two adjacent rows of the axial elastic units.

A second aspect of the present application provides a balloon catheter comprising the balloon peripheral constraining device of the above embodiments, and a balloon and catheter assembly, the balloon peripheral constraining device being arranged around the balloon and being capable of expanding from the original state to the fully extended state upon inflation of the balloon.

The third aspect of the present application also provides a method of manufacturing a balloon periphery constraint device, the method comprising the steps of:

S1, providing at least one axial braiding wire, a plurality of circumferential braiding wires and a braiding tool;

S2, weaving the axial weaving wires and the circumferential weaving wires through the weaving tool to form the structure of the balloon periphery constraint device;

S3, taking down the structure formed by braiding in the step S2 from the braiding tool after heat setting so as to obtain the balloon periphery constraint device.

According to some embodiments of the application, the step S2 comprises at least the steps of,

S21, winding the axial braiding wires onto pins at preset positions of the braiding tool according to a preset direction to form a plurality of rows of axial elastic units;

s22, winding the circumferential braiding wires onto pins at preset positions of the braiding tool so as to connect a plurality of rows of axial elastic units in the circumferential direction, and winding the circumferential braiding wires around the axial braiding wires and knotting and fixing the circumferential braiding wires at each connection position of the connection part and the first elastic part.

The technical scheme provided by the embodiment of the application can comprise the following beneficial effects:

Compared with a metal net manufactured by taking nickel-titanium alloy pipes as blanks and performing multiple processes such as cutting, grinding, heat setting, polishing and the like, the balloon periphery restraint device directly forms a net structure by weaving axial and circumferential weaving wires, the process that defective products are easy to produce in polishing and the like is omitted, and the qualification rate of finished products is obviously improved. In the balloon periphery constraint device, the first elastic part can be axially stretched to be in a basically straight state, so that the plurality of rows of axial elastic units can be axially stretched, meanwhile, the plurality of rows of circumferential elastic units are circumferentially connected to form a ring through the plurality of circumferential braided wires, and the second elastic part can be circumferentially stretched to finally enable each circumferential braided wire to be stretched to form a ring shape, and therefore, the circumferential spacing between the plurality of rows of axial elastic units can be changed accordingly, and the radial deformation requirement of the balloon is met. The circumferential braiding wires are fixed to the axial braiding wires at each connecting position of the connecting parts and the first elastic parts, so that the circumferential braiding wires and the axial braiding wires are mutually restrained at the positions fixedly connected in the process that the balloon peripheral restraining device stretches from an original state to a fully stretched state, the restraint device structure in the fully stretched state is ensured to be uniform, axial and circumferential restraint which is uniform and tends to be uniform can be provided for the inner balloon, and the balloon is prevented from being excessively deformed due to lack of restraint locally.

Drawings

FIG. 1 is a schematic view of the overall structure of a balloon peripheral constraint structure according to an embodiment of the present application;

FIG. 2 is an enlarged view of portion A of the balloon peripheral constraint structure shown in FIG. 1;

FIG. 3 is a schematic view of a partial structure of one axial spring unit in the balloon peripheral constraint structure shown in FIG. 1;

FIG. 4a is an enlarged view of a portion B of the balloon peripheral constraint structure shown in FIG. 1, showing the manner in which the axial braid wires are wrapped around the circumferential braid wires;

FIG. 4b is an embodiment of an end knotting attachment of axial/circumferential braided filaments;

FIG. 5 is a schematic view showing an unfolding structure of a knitting tool according to an embodiment of the present application;

FIG. 6 is a schematic view of the balloon peripheral constraint structure in a fully deployed state according to an embodiment of the present application.

Reference numerals: 100. axially braiding wires; 11. an axial elastic unit; 110. an elastic subunit; 1101. a first elastic portion; 1102. a connection part; 12. a connection end;

200. Circumferentially braiding wires; 21. a second elastic part; 22. knotting the fixing part;

300. Braiding a tool; 31. a support; 32. and (5) inserting pins.

Detailed Description

Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The manner described in the following exemplary embodiments does not represent all the manners consistent with the present application, but merely preferred embodiments of the present application, and those skilled in the art will appreciate that any simple modification, equivalent variation and modification of the above embodiments according to the technical matter of the present application falls within the scope of the present application, while making a few changes or modifications equivalent to the equivalent embodiments using the technical matter disclosed above without departing from the technical matter of the present application.

Further, in the description of the present application, the axial direction and the circumferential direction are the length direction and the diameter direction of the balloon, respectively; the flat condition is not necessarily required to have the two sections of the folded elastic portion stretched to a collinear condition in the geometric concept, so long as the stretched condition is substantially in a nearly flat or relatively smooth arcuate condition.

As shown in fig. 1-3, a balloon peripheral restraint device according to an embodiment of the present application includes one or more axial braided filaments 100, and a plurality of circumferential braided filaments 200. The axial braid wires 100 and the circumferential braid wires 200 are braided into a ring-net structure by a braiding tool 300 shown in fig. 5 and are used to be sleeved to the outer circumference of the balloon. In the process of balloon inflation, the ring-net-shaped balloon periphery constraint structure can restrain the deformation of the balloon, so that the inflation and expansion performance of the balloon is improved.

Before the balloon is inflated with the inflation medium, the balloon is in a folded state, and at the moment, the balloon periphery restraint device sleeved on the periphery of the balloon is in an original state before being unstressed; the balloon is gradually expanded along with inflation medium filled into the balloon through the catheter assembly, and at the moment, the balloon periphery restraint device sleeved on the periphery of the balloon periphery is gradually stretched to a fully-expanded state. As shown in fig. 6, when the balloon periphery constraint device is in a fully deployed state, the structure formed by the axial braided wire 100 and the circumferential braided wire 200 is spread in an approximately rectangular grid shape surrounding the circumference of the balloon, and the balloon body of the balloon can slightly protrude outward from the grid to form pillow-shaped protrusions.

In the original state, as shown in fig. 2 and 3, one or more axial braided wires 100 are bent around a plurality of points to form a plurality of rows of axial elastic units 11, and the structure of a single axial elastic unit 11 is shown in fig. 3. The plurality of rows of axial elastic elements 11 are circumferentially arranged and connected by circumferential braiding wires 200.

With continued reference to FIG. 3, each row of axially resilient units 11 in turn includes a plurality of axially connected resilient subunits 110. As shown in fig. 2 in combination with fig. 3, each elastic subunit 110 includes at least one bent first elastic portion 1101, and connection portions 1102 connected to both ends of the first elastic portion 1101. The circles labeled a-i in fig. 2 may be pins 32 at appropriate locations on the knitting tool 300, hereinafter. The axial braided wire 100 bypasses the point e obliquely upwards along the solid arrow direction in the figure after bypassing the lower circular arc of the point f, so that a connecting part 1102 is formed between the point f and the point e; the axial braided wire 100 continues to obliquely upward bypass the arc on the upper side of the h point and then obliquely downward, and a first bending elastic part 1101 is formed on both sides of the h point; after the axial braid wire 100 bypasses the point i, another connection 1102 is formed between the point h and the point i, and an elastic subunit 110 shown in fig. 3 is formed according to the braiding and winding method described above.

The circumferential knitting yarn 200 is provided on both end sides of each first elastic portion 1101. In other words, the entire balloon peripheral restraint has a plurality of circumferential braided filaments 200 depending on how many elastic subunits 110 are within each axial elastic element 11.

Each circumferential knitting yarn 200 is continuously folded one round to form a plurality of folded second elastic portions 21. Also, at each connection of the first elastic portion 1101 and the both end connection portions 1102, the circumferential knitting yarn 200 is fixed to the axial knitting yarn 100 in an appropriate manner.

With continued reference to fig. 2, the circumferential knitting yarn 200 sequentially passes around points a, b, c, d, e, f, and g in the direction of the open arrow in the drawing, thereby forming four second elastic portions 21.

In the fully extended state, the first elastic portion 1101 can be extended in the axial direction to a flat state, while the second elastic portion 21 is extended in the circumferential direction, eventually forming each circumferential braid wire 200 into a circular ring shape.

In the embodiment shown in fig. 1, the first elastic portion 1101 is configured such that the axial braid 100 is bent around a certain point, and the first elastic portion 1101 has an approximately inverted V-shape in the illustrated orientation. Similarly, the second elastic portion 21 is configured such that the circumferential knitting yarn 200 is folded around a certain point, and in the illustrated orientation, the second elastic portion 21 is approximately V-shaped after being rotated by 90 °. It can be appreciated that the first elastic portion 1101 and the second elastic portion 21 may be formed by bending around a plurality of points for a plurality of times, and a single bending can facilitate the knitting process.

In the prior art of forming a metal net structure by cutting a pipe, the pipe wall of the pipe is cut to form spaced hollow structures, so that the stretched structure can be ensured to be in a stable net shape. In the present application, however, the balloon periphery restraining means is formed by weaving the axial and circumferential woven wires, and if the axial woven wires 100 and the circumferential woven wires 200 relatively slip when they are stretched in response to the inflation of the balloon, the mesh structure formed in the fully stretched state may be uneven, thereby making it difficult to achieve the purpose of uniformly restraining the balloon.

For this reason, in the above embodiment, at each connection of the first elastic portion 1101 and the two end connection portions 1102, the circumferential knitting yarn 200 is fixed to the axial knitting yarn 100 in a proper manner, so that mutual constraint of the circumferential knitting yarn 200 and the axial knitting yarn 100 at the fixed connection during the stretching process is ensured, relative sliding is not generated between them, and finally the structure of the constraint device in the fully stretched state tends to be uniform, so that axial and circumferential constraint which tends to be uniform and uniform can be provided for the inner balloon, and excessive deformation of the balloon due to lack of constraint is avoided.

As shown in fig. 2, circumferential braid wires 200 are secured to axial braid wires 100 at points a, b, c, d, e, f and g, respectively. Since the circumferential knitting yarn 200 is fixed to each of the junctions between the first elastic portion 1101 and the both end connection portions 1102, the circumferential knitting yarn 200 on one side overlaps with one of the junctions 1102 and the circumferential knitting yarn 200 on the other side exists alone on each of the second elastic portions 21 at a boundary between the folds in the circumferential direction. Taking two sides of the point e in fig. 2 as an example: the circumferential braid wire 200 between the point d and the point e exists alone, and the circumferential braid wire 200 and one connection 1102 exist between the point e and the point f. In this way, the connection 1102 of the axial braided wire 100 can also assist the circumferential braided wire 200 in the circumferential direction to act as a constraining balloon when the balloon outer circumference constraining device changes from the original state to the fully extended state.

In particular, after the circumferential knitting yarn 200 is continuously folded for one turn, the ends of the end portion and the end portion need to be fixed by a suitable means, such as knotting, and the fixed position has a risk of breaking, and the connection portion 1102 overlaps a part of the circumferential knitting yarn 200, so that the breaking process of the circumferential knitting yarn 200 is limited by the axial knitting yarn 100, and the risk of breaking the fixed position is reduced.

In one embodiment, all the axial elastic units 11 are formed by continuously bending one axial braided wire 100, and the head and tail ends of the one axial braided wire 100 are fixedly connected to each other in a knotting manner. The continuous bending of the single axial braided wire 100 can save the connection process between a plurality of axial braided wires 100, the braiding process is more convenient, and meanwhile, the diameter of the braided wire is only about 25 microns due to the small size of the balloon, so that no matter what fixing mode is adopted, the positions where two sections of braided wires are connected with each other always have the risk of fracture and disconnection, and the fracture and disconnection risk is greatly reduced by adopting one continuous axial braided wire 100, and the strength of the structure is ensured by the strength of the braided wire.

As shown in fig. 2, all the connection portions 1102 extend obliquely toward the same direction (the connection portions 1102 extend obliquely upward in the drawing). Thus, when the balloon peripheral restraint device is unfolded and deformed, the inclined connecting portions 1102 are gradually deformed to an axially extending direction, the elasticity of the device in the axial direction is increased, and the connecting portions 1102 extend obliquely in the same direction, so that the deformation of the whole device tends to be uniform.

As previously described in connection with the illustrations of fig. 2 and 4 a. At each connection of the connection portion 1102 and the first elastic portion 1101, the circumferential knitting yarn 200 is fixed to the axial knitting yarn 100 in such a manner that the circumferential knitting yarn 200 is wound around the axial knitting yarn 100 at least one turn in the arrow direction marked in the drawing as shown in fig. 4a, and then knotted, so that the circumferential knitting yarn 200 can be reliably fixed to the axial knitting yarn 100. It will be appreciated that the securing location may also assist in other suitable means, such as increasing the number of turns of circumferential braid 200, dispensing glue at the junction, etc.

As shown in fig. 6, in the illustrated fully extended state, the length of the first elastic portion 1101 after being extended in the axial direction is equal to the length of the second elastic portion 21 after being extended in the circumferential direction. Thus, the deployment structure of the balloon periphery restraining device is similar to a net structure comprising a plurality of square grids, and the stress condition of the metal net structure tends to be uniform.

In one embodiment, both axial braid wires 100 and circumferential braid wires 200 are provided as nitinol wires. As described above, the conventional metal mesh structure is usually formed by cutting a nickel-titanium alloy tube, and mainly considers that the nickel-titanium alloy is a metal with shape memory function, has the characteristics of super elasticity, good compatibility with human body, no toxicity and the like, and is particularly suitable for being used in interventional medical instruments. Thus, nitinol wires are also employed in embodiments of the present application.

As shown in fig. 1 and 6, the axial braid wires 100 are formed with connection ends 12 at both axial ends of the axial elastic units 11, the connection ends 12 being disposed between adjacent two rows of the axial elastic units 11. The balloon peripheral restraint device of the present application ultimately needs to be attached to the exterior of the balloon in the balloon catheter, and the attachment end 12 can be used for later welding with the distal and proximal ends of the balloon.

The embodiment of the application also provides a balloon catheter, which comprises the balloon peripheral restraint device in any embodiment, and a balloon and catheter assembly, wherein the balloon peripheral restraint device is sleeved outside the balloon and can be unfolded from an original state to a fully-extended state along with the inflation of the balloon. In the embodiment in which the axial braid wires 100 are formed with the connection ends 12, the connection ends 12 are welded to the distal and proximal ends of the balloon.

The embodiment of the application also provides a manufacturing method of the balloon periphery constraint device, which comprises the following steps:

s1, providing at least one axial braiding wire 100, a plurality of circumferential braiding wires 200 and a braiding tool 300;

S2, weaving the axial weaving wires 100 and the circumferential weaving wires 200 through a weaving tool 300 to form the structure of the balloon periphery constraint device described in the embodiment;

s3, taking down the structure formed by braiding in the step S2 from the braiding tool 300 after heat setting so as to obtain the balloon periphery constraint device.

As shown in fig. 5, the knitting tool 300 of one embodiment includes a support 31 and a plurality of pins 32 detachably connected to the support 31. In the above step S2, the axial knitting yarn 100 and the circumferential knitting yarn 200 are bent around the pins 32 at different positions on the support 31 to form the first elastic portion 1101 and the second elastic portion 21. In the unfolded configuration of the support 31 shown in fig. 5, the support 31 is formed as a body of revolution, for example a cylindrical or polygonal column, on the outer circumference of which the pins 32 are inserted during braiding.

The contact pin 32 is detachably connected with the supporting member 31, and when the knitted structure needs to be removed, the fixed relation between the knitted structure and the knitting tool 300 can be directly released by pulling out the contact pin 32, so that the knitted structure needs to be kept in shape and obtain elasticity through heat setting, and the structure formed by moving knitting needs to be avoided as much as possible before heat setting. In addition, during braiding, one or more axial braiding wires 100 may be used to complete braiding of all axial elastic units 11, and then circumferential braiding wires 200 may be wound around the braiding tool 300.

In one embodiment, the step S2 further includes at least the following steps,

S21, winding the axial braiding wires 100 onto the pins 32 at the preset position of the braiding tool 300 according to the preset direction to form a plurality of rows of axial elastic units 11;

s22, winding the circumferential knitting yarn 200 around the pins 32 at the preset position of the knitting tool 300 to connect the plurality of rows of axial elastic units 11 in the circumferential direction, and winding the circumferential knitting yarn 200 around the axial knitting yarn 100 for one turn and knotting and fixing at each connection of the connection portion 1102 and the first elastic portion 1101.

Further, when both ends of the axial braided wire 100 and the circumferential braided wire 200 are fixed to each other, the fixation of the knot may be performed in the manner shown in fig. 4b, that is, the thread ends x and y in the drawing are respectively pulled in the general direction indicated by the arrows in the drawing to form a fixed knot.

Claims (10)

1. A balloon peripheral restraint device having at least an unstressed, original state and a stressed, fully extended state, the balloon peripheral restraint device comprising one or more axial braided filaments (100), and a plurality of circumferential braided filaments (200), wherein in the original state:

One or more axial braiding wires (100) are bent around a plurality of fixed points to form a plurality of rows of axial elastic units (11), and the plurality of rows of axial elastic units (11) are circumferentially distributed and connected through the circumferential braiding wires (200);

Each row of axial elastic units (11) further comprises a plurality of elastic sub-units (110) which are connected in the axial direction, each elastic sub-unit (110) comprises at least one bent first elastic part (1101), and connecting parts (1102) connected to two ends of the first elastic part (1101);

the circumferential braiding wires (200) are correspondingly arranged at two end sides of each first elastic part (1101), each circumferential braiding wire (200) is continuously bent for one circle to form a plurality of bent second elastic parts (21), and the circumferential braiding wires (200) are fixed to the axial braiding wires (100) at each connecting position of the connecting parts (1102) and the first elastic parts (1101);

In the fully extended state: the first elastic portion (1101) is stretched in an axially straight state, and the second elastic portion (21) is stretched in a circumferential direction so that each circumferential braid wire (200) is stretched in a circular shape.

2. Balloon peripheral constraint device according to claim 1, characterized in that all the axial elastic units (11) are formed by continuously bending one axial braided wire (100), and the head and tail ends of the axial braided wire (100) are fixedly connected to each other in a knotted manner.

3. The balloon peripheral restraint device according to claim 1, wherein all the connection portions (1102) extend obliquely in the same direction and/or,

The first elastic part (1101) is formed by bending the axial braided wire (100) around a certain point, and the second elastic part (21) is formed by bending the circumferential braided wire (200) around a certain point.

4. The balloon peripheral constraint device of claim 1, wherein at each connection of the connection portion (1102) and the first elastic portion (1101), the circumferential braided wire (200) is wound around the axial braided wire (100) at least one revolution and knotted to be fixed to the axial braided wire (100).

5. The balloon peripheral constraint device of claim 1, wherein in the fully extended state, the first elastic portion (1101) has an axially extended length equal to the second elastic portion (21) has a circumferentially extended length.

6. The balloon peripheral constraint device of any of claims 1-5, wherein the axial braided wire (100) and the circumferential braided wire (200) are both provided as nitinol wires.

7. Balloon peripheral constraint device according to claim 1, wherein said axial braided wires (100) are formed with connection ends (12) at both axial ends of said axial elastic units (11), said connection ends (12) being arranged between two adjacent rows of said axial elastic units (11).

8. A balloon catheter comprising the balloon peripheral restraint device of any one of claims 1-5, and a balloon and catheter assembly, the balloon peripheral restraint device being disposed over the balloon and being capable of expanding from the original state to the fully extended state upon inflation of the balloon.

9. A method of manufacturing a balloon peripheral restraint device, the method comprising the steps of:

s1, providing at least one axial braiding wire (100), a plurality of circumferential braiding wires (200) and a braiding tool (300);

S2, braiding the axial braiding wires (100) and the circumferential braiding wires (200) through the braiding tool (300) to form the structure of the balloon periphery constraint device according to any one of claims 1-7;

S3, taking down the structure formed by braiding in the step S2 from the braiding tool (300) after heat setting so as to obtain the balloon periphery constraint device.

10. The method of manufacturing a balloon peripheral restraint device of claim 9 wherein step S2 comprises at least the steps of,

S21, winding the axial braiding wires (100) onto pins (32) at preset positions of the braiding tool (300) according to a preset direction to form a plurality of rows of axial elastic units (11);

S22, winding the circumferential braiding wires (200) onto pins (32) at preset positions of the braiding tool (300) so as to connect a plurality of rows of axial elastic units (11) in the circumferential direction, wherein the circumferential braiding wires (200) are wound around the axial braiding wires (100) for one circle and knotted and fixed at each connection position of the connection part (1102) and the first elastic part (1101).