A displacement-resistant, self-adaptive, self-locking human endoscopic stent and its fabrication method

Abstract

This invention relates to an anti-displacement adaptive self-locking human endovascular stent and its manufacturing method, belonging to the field of medical devices. The invention includes a stent unit and a connecting unit, with adjacent stent units connected by the connecting unit. Its structural features are as follows: each stent unit includes a main frame arranged in a rhomboid structure, and connecting beams, transition beams, and tenon-and-mortise beams disposed within the main frame. The connecting beams, transition beams, and tenon-and-mortise beams are connected sequentially. Both the connecting beams and the tenon-and-mortise beams are connected to the main frame. Each of the two tenon-and-mortise beams has multiple tenons, with mortises formed between adjacent tenons. A tenon on one tenon-and-mortise beam connects to a mortise on another tenon-and-mortise beam, wherein the number of tenons is not less than three, and the number of mortises is not less than two.

Description

Technical Field

[0001] This invention relates to an anti-displacement adaptive self-locking human lumen stent and its manufacturing method, belonging to the field of medical devices. Background Technology

[0002] In the medical field, the development of human lumen stents has gone through a long process. Early human lumen stents were mainly rigid structures, mostly made of metal materials, such as stainless steel. Although these stents can support the lumen to a certain extent and alleviate the problem of stenosis, they have many limitations due to the characteristics of their materials. For example, rigid stents cannot adapt to the physiological activities of the human lumen and are prone to wear and tear on the inner wall of the lumen, causing inflammatory reactions.

[0003] With the advancement of medical technology, expandable stents have emerged. They can be expanded in the body through balloon dilation and other methods to better fit the shape of the lumen and improve the treatment effect. However, as clinical applications continue to deepen, problems with expandable stents have gradually emerged. At present, human lumen stents still face many challenges in terms of materials and structure.

[0004] From a materials perspective, most traditional stent materials are non-degradable. Patients need to carry the stent for a long time after implantation, which not only increases the burden on the body but may also cause complications. If the stent needs to be removed, a second surgery is required, which undoubtedly increases the patient's pain and medical costs.

[0005] In terms of structure, existing stents generally have insufficient support, resulting in poor stent stability. Some stents are prone to displacement within the body's lumen, leading to poor treatment results and potentially causing more serious health problems. In addition, many stents are too rigid after placement and cannot adapt to physiological changes in the body's lumen, making it difficult to meet the complex physiological needs of the human body.

[0006] Therefore, recognizing the above problems, a new stent structure combined with biodegradable materials is needed to treat luminal diseases. Furthermore, this structure can enable the stent to be further developed into a biodegradable stent with a certain degree of self-expansion, thereby treating luminal diseases in some special locations.

[0007] Taking invention patent number CN201611261833.9 as an example, this patent discloses a "biodegradable vascular stent and its preparation method". The stent structure includes a covered stent and a bare stent connected to the proximal end of the covered stent. The stent also includes an axially inextensible positioning device, which is fixed to the proximal starting end of the covered stent. Although it improves the support of the stent to a certain extent, it still has the following disadvantages: the three-dimensional structure design of the stent is relatively simple, and its support is obtained by the deformation of the stent crests and troughs. It mainly relies on the strain of the material at the crests and troughs, which has limited effect on preventing stent displacement. This makes the stent prone to displacement after implantation, affecting the treatment effect. It also lacks an adaptive adjustment mechanism for dynamic changes in the lumen. Summary of the Invention

[0008] The purpose of this invention is to overcome the above-mentioned deficiencies in the prior art and to provide a structurally reasonable anti-displacement adaptive self-locking human body lumen stent and its manufacturing method. The stent is used in human body lumens and is made of biodegradable materials.

[0009] The technical solution adopted by the present invention to solve the above problems is as follows: the anti-displacement adaptive self-locking human body cavity stent includes a stent unit and a connecting unit. Adjacent stent units are connected through the connecting unit. Its structural features are as follows: the stent unit includes a main frame arranged in a rhomboid structure, and a connecting beam, a transition beam and a tenon beam arranged inside the main frame. The connecting beam, the transition beam and the tenon beam are connected in sequence. The connecting beam and the tenon beam are both connected to the main frame. Multiple tenons are provided on each of the two tenon beams. A mortise is formed between adjacent tenons. The tenon on one tenon beam is connected to the mortise on the other tenon beam. The number of tenons is not less than 3 and the number of mortises is not less than 2.

[0010] Furthermore, the two sides of the tenon are respectively the front edge and the side edge of the tenon, the front edge of the tenon is convex, and the side edge of the tenon is convex or concave.

[0011] Furthermore, the tenon groove is provided with a groove bottom edge, and there is a gap between the groove bottom edge and the end of the tenon.

[0012] Furthermore, the tenon and mortise beam is configured with a slightly convex or slightly concave shape.

[0013] Furthermore, the tenon and the mortise are fitted with a clearance, meaning that the tenon can have a certain amount of sliding space within the mortise.

[0014] Furthermore, the connecting crossbeam is I-shaped, U-shaped, V-shaped, S-shaped, or M-shaped, the transition crossbeam is U-shaped or V-shaped, and the connecting unit is I-shaped, U-shaped, V-shaped, S-shaped, or M-shaped.

[0015] Furthermore, another technical objective of the present invention is to provide a method for manufacturing an anti-displacement adaptive self-locking human body lumen stent.

[0016] The above-mentioned technical objective of the present invention is achieved through the following technical solution.

[0017] A method for manufacturing an anti-displacement adaptive self-locking human body lumen stent, characterized in that: the manufacturing method employs a femtosecond laser integrated processing process as follows:

[0018] S1. Material pretreatment:

[0019] Biodegradable metal sheets (such as magnesium alloys and zinc alloys) or polymer sheets (such as PLGA) are used as the substrate, and the surface is coated with a photosensitive resist.

[0020] S2, femtosecond laser precision engraving:

[0021] The substrate is directly cut using an ultrashort pulse femtosecond laser (pulse width <500fs, wavelength 1030nm) to form a support unit, connecting unit, connecting beam, transition beam, mortise and tenon beam, tenon, and mortise groove in one step.

[0022] Key parameters:

[0023] Laser power: 10-50W (metals) / 5-20W (polymers)

[0024] Scanning speed: 100-500 mm / s (metals) / 200-1000 mm / s (polymers)

[0025] Focal point diameter: 10-30μm, ensuring no heat-affected zone (HAZ) at the cutting edge;

[0026] S3, In-situ forming mortise and tenon structure:

[0027] Through laser path programming, tenons and mortises are directly carved while the main frame is being cut, leaving a sliding space of 0.05-0.2mm, eliminating the need for secondary assembly;

[0028] S4. Deburring and surface finishing: using a low-power femtosecond laser (energy density 0.1-0.3 J / cm²). 2 Scan the cutting edge to remove micron-level burrs.

[0029] Furthermore, another technical objective of the present invention is to provide a method for manufacturing an anti-displacement adaptive self-locking human body lumen stent.

[0030] The above-mentioned technical objective of the present invention is achieved through the following technical solution.

[0031] A method for manufacturing an anti-displacement, self-adaptive, self-locking human endovascular stent, characterized in that the manufacturing method employs a micro-injection molding process as follows:

[0032] S1. Mold Design:

[0033] High-precision micro-injection molds (tolerance ±5μm) are used. The mold cavity contains a complete three-dimensional shape of support unit, connecting unit, connecting beam, transition beam, tenon beam, tenon, and mortise.

[0034] S2, Material Injection and Molding:

[0035] When the support is made of metal: a biodegradable metal melt (such as magnesium alloy, melting temperature 650-700℃) is injected into the mold under high pressure, and after holding the pressure and cooling, it is demolded to form a complex metal support in one go.

[0036] When the support is made of polymer: PLGA or other materials melt (temperature 180-220℃) is injected into the mold, and rapid curing is achieved by controlling the mold temperature (cooling rate 10-20℃ / s);

[0037] S3. Demolding and self-locking calibration:

[0038] After demolding, a complete bracket is obtained directly. The tenons and mortises are precisely fitted by the mold to achieve an interference fit, requiring no additional processing.

[0039] S4. Deburring and surface finishing: Eliminate injection flow marks and parting lines through plasma etching (Ar / O2 mixed gas) or supercritical CO2 cleaning.

[0040] Furthermore, another technical objective of the present invention is to provide a method for manufacturing an anti-displacement adaptive self-locking human body lumen stent.

[0041] The above-mentioned technical objective of the present invention is achieved through the following technical solution.

[0042] A method for manufacturing an anti-displacement, self-adaptive, self-locking human endoscopic stent, characterized in that the manufacturing method involves a multi-material 3D printing integrated molding process as follows:

[0043] S1. Printing Technology Selection:

[0044] When the support is made of metal: Selective laser melting (SLM) technology is used, with magnesium alloy powder as the raw material, to melt and form it layer by layer;

[0045] When the scaffold is made of polymer: Fused deposition modeling (FDM) or digital light processing (DLP) are used, and PLGA wires or photosensitive resin are employed;

[0046] When the support is made of composite material: metal (powder) and polymer (melt) are printed simultaneously through a multi-nozzle system to achieve integrated processing of heterogeneous materials;

[0047] S2, Synchronous Structure Construction:

[0048] In the 3D model, support units, connecting units, connecting beams, transition beams, mortise and tenon beams, tenons, and mortises are predefined. The entire process is completed in one printing step through path planning. The gap (sliding space) between the tenons and mortises is directly controlled by the printing accuracy (±0.02mm).

[0049] S3, In-situ Post-curing:

[0050] The metal support is annealed (300-400℃, argon atmosphere) to eliminate internal stress;

[0051] Polymer scaffolds enhance interlayer bonding through ultraviolet light (DLP) or thermosetting (FDM);

[0052] S4. Deburring and surface finishing: Chemical mechanical polishing (CMP) or ultrasonic microbead impaction (5μm particle size) is used to reduce surface roughness (Ra<0.1μm).

[0053] Furthermore, the tenon and mortise are aligned and aligned:

[0054] Use an optical measurement system (such as a laser confocal microscope) to check the fit tolerance of the tenon and mortise. If necessary, adjust the slip space to ±0.01mm by local laser ablation or micro-injection molding.

[0055] Compared with the prior art, the present invention has the following advantages:

[0056] 1. Processing flexibility: Femtosecond laser, micro-injection molding, and 3D printing can all be used to independently achieve the integrated molding of the stent, adapting to different materials (metal / polymer) and clinical scenarios.

[0057] 2. Precision and efficiency: Integrated molding reduces assembly steps, and combined with post-processing technology, the surface roughness (Ra<0.1μm) and tenon and mortise tolerance (±0.01mm) meet medical-grade standards.

[0058] 3. Functional compatibility: Regardless of the process used, it can retain the tenon and mortise self-locking, self-adjusting and biodegradable characteristics to meet the long-term implantation needs of dynamic lumens such as blood vessels and digestive tract.

[0059] 4. Excellent anti-displacement performance: Through the design of the mortise and tenon structure (tenon 6 and mortise 7), the bracket can achieve self-locking after expansion, effectively preventing the bracket from shifting in the cavity, especially in curved or dynamically changing cavities.

[0060] 5. Strong self-adjustment capability: The tenon and mortise structure of the stent allows for a certain amount of sliding space, enabling it to self-adjust according to the contraction or expansion of the lumen, ensuring that the stent is always in close contact with the lumen wall.

[0061] 6. High mechanical strength: The main frame of the stent adopts a rhomboid design, combined with mortise and tenon structure and connecting units, which significantly improves the overall mechanical strength of the stent and ensures its support performance in complex physiological environments.

[0062] 7. Controllable degradation rate: The stent is made of biodegradable materials. By precisely controlling the degradation rate of the materials, the stent is ensured to degrade safely after fulfilling its supporting function, avoiding long-term effects on patients.

[0063] 8. Wide range of applications: The stent has a flexible structural design, and the number and size of the tenon and mortise structure can be adjusted according to the shape requirements of different lumens, making it suitable for the treatment of various lumens such as blood vessels, esophagus, and bile duct. Attached Figure Description

[0064] Figure 1 This is a schematic diagram of the unfolded structure of the anti-displacement adaptive self-locking human body lumen stent according to an embodiment of the present invention.

[0065] Figure 2 This is a partial structural schematic diagram of the anti-displacement adaptive self-locking human body lumen stent according to an embodiment of the present invention.

[0066] Figure 3 This is a schematic diagram of the tubular structure of the anti-displacement adaptive self-locking human body lumen stent according to an embodiment of the present invention.

[0067] Figure 4 This is a schematic diagram of the tubular structure of the anti-displacement adaptive self-locking human body lumen stent according to an embodiment of the present invention.

[0068] In the diagram: Support unit 1, Connecting unit 2, Connecting beam 3, Transition beam 4, Mortise and tenon beam 5, Tenon 6, Mortise and tenon 7.

[0069] Falcon front edge 61, Falcon side edge 62

[0070] The bottom edge of the groove is 71. Detailed Implementation

[0071] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The following embodiments are explanations of the present invention, but the present invention is not limited to the following embodiments.

[0072] Example

[0073] See Figures 1 to 4As shown in the accompanying drawings, the structures, proportions, sizes, etc., depicted are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness or purpose of the invention, should still fall within the scope of the disclosed technical content. Furthermore, the use of terms such as "upper," "lower," "left," "right," "middle," and "one" in this specification is merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0074] Example 1: The anti-displacement adaptive self-locking human body cavity stent in this example includes a stent unit 1 and a connecting unit 2. Adjacent stent units 1 are connected through the connecting unit 2. The stent unit 1 includes a main frame with a rhomboid structure, and a connecting beam 3, a transition beam 4, and a tenon beam 5 disposed inside the main frame. The connecting beam 3, the transition beam 4, and the tenon beam 5 are connected in sequence. Both the connecting beam 3 and the tenon beam 5 are connected to the main frame. Both tenon beams 5 are provided with multiple tenons 6. A mortise 7 is formed between adjacent tenons 6. The tenon 6 on one tenon beam 5 is connected to the mortise 7 on the other tenon beam 5. The number of tenons 6 is not less than 3, and the number of mortise 7 is not less than 2.

[0075] In this embodiment, the tenon 6 has a tenon front edge 61 and a tenon side edge 62 on both sides. The tenon front edge 61 is convex, and the tenon side edge 62 is convex or concave. The tenon groove 7 has a groove bottom edge 71, and there is a gap between the groove bottom edge 71 and the end of the tenon 6.

[0076] In this embodiment, the tenon beam 5 is designed with a slightly convex or slightly concave shape. The tenon 6 and the mortise 7 are fitted with a clearance, meaning that the tenon 6 can have a certain sliding space in the mortise 7, thereby achieving self-locking during the expansion of the stent. The connecting beam 3 is I-shaped, U-shaped, V-shaped, S-shaped, or M-shaped. The transition beam 4 is U-shaped or V-shaped and is used to connect the main frame between different stent units to ensure the continuity and stability of the overall stent structure. The connecting unit 2 is I-shaped, U-shaped, V-shaped, S-shaped, or M-shaped to ensure that the stent can adapt to the bending and dynamic changes of the lumen after implantation.

[0077] The working principle of this anti-displacement adaptive self-locking human body lumen stent is as follows:

[0078] Stent Expansion and Self-Locking: During stent implantation, the stent is expanded by a balloon, and the main frame of stent unit 1 deforms. Points A and B move away from each other, while points C and D move closer to each other, pushing the tenon 6 into the mortise 7 to form a self-locking structure. By adjusting the size of the mortise 7 along the circumference (i.e., the length of the bottom edge 71 of the groove), the range of motion of the stent in the self-locking state can be controlled to adapt to the contraction and relaxation of the lumen.

[0079] Adaptive adjustment: The tenon and mortise structure of the support (tenon 6 and mortise 7) adopts a clearance fit design, which allows for a certain amount of sliding space. When the lumen contracts or expands, the tenon 6 can slide in the mortise 7 to achieve adaptive adjustment of the support and ensure that the support is always in close contact with the lumen wall.

[0080] Degradation and absorption: The stent is made of biodegradable materials. After fulfilling its support function, the material gradually degrades and is absorbed by the body, avoiding the risk of removal by a second surgery.

[0081] In other words, during stent expansion, stent unit 1 deforms, points A and B move away from each other, and points C and D move closer to each other, causing tenon 6 to enter mortise 7, forming a self-locking structure. By adjusting the size of mortise 7 along the circumference, i.e. the length of the bottom edge 71 of the groove, the range of motion of the stent along the circumference under self-locking conditions can be adjusted to adapt to the contraction and dilation of lumens in certain locations, such as blood vessels. The number and size of tenons 6 and mortise 7 are determined according to the location being treated, with no less than 3 tenons 6 and no less than 2 mortise 7.

[0082] Figure 1 The diagram shows the unfolded shape of a human luminal stent. Figure 1 Bending in the direction shown by the middle arrow will bend the human body stent into... Figure 3 Medium-sized tubular structure.

[0083] The fabrication method for the anti-displacement adaptive self-locking human body lumen stent is to use femtosecond laser integrated processing, and the process is as follows:

[0084] S1. Material pretreatment:

[0085] Biodegradable metal sheets (such as magnesium alloys and zinc alloys) or polymer sheets (such as PLGA) are used as the substrate, and the surface is coated with a photosensitive resist.

[0086] S2, femtosecond laser precision engraving:

[0087] The substrate is directly cut using an ultrashort pulse femtosecond laser (pulse width <500fs, wavelength 1030nm) to form the support unit 1, connecting unit 2, connecting beam 3, transition beam 4, tenon beam 5, tenon 6, and mortise 7 in one piece.

[0088] Key parameters:

[0089] Laser power: 10-50W (metals) / 5-20W (polymers)

[0090] Scanning speed: 100-500 mm / s (metals) / 200-1000 mm / s (polymers)

[0091] Focal point diameter: 10-30μm, ensuring no heat-affected zone (HAZ) at the cutting edge;

[0092] S3, In-situ forming mortise and tenon structure:

[0093] Through laser path programming, tenons 6 and mortises 7 are directly carved while the main frame is being cut, leaving a sliding space of 0.05-0.2mm, eliminating the need for secondary assembly;

[0094] S4. Deburring and surface finishing: using a low-power femtosecond laser (energy density 0.1-0.3 J / cm²). 2 Scan the cutting edge to remove micron-level burrs.

[0095] S5. Tenon 6 and mortise 7 fit calibration: Use an optical measurement system (such as a laser confocal microscope) to check the fit tolerance of tenon 6 and mortise 7. If necessary, adjust the slip space to ±0.01mm by local laser ablation or micro-injection molding.

[0096] Example 2: The anti-displacement adaptive self-locking human body cavity stent in this example includes a stent unit 1 and a connecting unit 2. Adjacent stent units 1 are connected through the connecting unit 2. The stent unit 1 includes a main frame with a rhomboid structure, and a connecting beam 3, a transition beam 4, and a tenon beam 5 disposed inside the main frame. The connecting beam 3, the transition beam 4, and the tenon beam 5 are connected in sequence. Both the connecting beam 3 and the tenon beam 5 are connected to the main frame. Each of the two tenon beams 5 is provided with multiple tenons 6. A mortise 7 is formed between adjacent tenons 6. The tenon 6 on one tenon beam 5 is connected to the mortise 7 on the other tenon beam 5. The number of tenons 6 is not less than 3, and the number of mortise 7 is not less than 2.

[0097] In this embodiment, the tenon 6 has a tenon front edge 61 and a tenon side edge 62 on both sides. The tenon front edge 61 is convex, and the tenon side edge 62 is convex or concave. The tenon groove 7 has a groove bottom edge 71, and there is a gap between the groove bottom edge 71 and the end of the tenon 6.

[0098] In this embodiment, the tenon beam 5 is designed with a slightly convex or slightly concave shape. The tenon 6 and the mortise 7 are fitted with a clearance, meaning that the tenon 6 can have a certain sliding space in the mortise 7, thereby achieving self-locking during the expansion of the stent. The connecting beam 3 is I-shaped, U-shaped, V-shaped, S-shaped, or M-shaped. The transition beam 4 is U-shaped or V-shaped and is used to connect the main frame between different stent units to ensure the continuity and stability of the overall stent structure. The connecting unit 2 is I-shaped, U-shaped, V-shaped, S-shaped, or M-shaped to ensure that the stent can adapt to the bending and dynamic changes of the lumen after implantation.

[0099] The working principle of this anti-displacement adaptive self-locking human body lumen stent is as follows:

[0100] Stent Expansion and Self-Locking: During stent implantation, the stent is expanded by a balloon, and the main frame of stent unit 1 deforms. Points A and B move away from each other, while points C and D move closer to each other, pushing the tenon 6 into the mortise 7 to form a self-locking structure. By adjusting the size of the mortise 7 along the circumference (i.e., the length of the bottom edge 71 of the groove), the range of motion of the stent in the self-locking state can be controlled to adapt to the contraction and relaxation of the lumen.

[0101] Adaptive adjustment: The tenon and mortise structure of the support (tenon 6 and mortise 7) adopts a clearance fit design, which allows for a certain amount of sliding space. When the lumen contracts or expands, the tenon 6 can slide in the mortise 7 to achieve adaptive adjustment of the support and ensure that the support is always in close contact with the lumen wall.

[0102] Degradation and absorption: The stent is made of biodegradable materials. After fulfilling its support function, the material gradually degrades and is absorbed by the body, avoiding the risk of removal by a second surgery.

[0103] In other words, during stent expansion, stent unit 1 deforms, points A and B move away from each other, and points C and D move closer to each other, causing tenon 6 to enter mortise 7, forming a self-locking structure. By adjusting the size of mortise 7 along the circumference, i.e. the length of the bottom edge 71 of the groove, the range of motion of the stent along the circumference under self-locking conditions can be adjusted to adapt to the contraction and dilation of lumens in certain locations, such as blood vessels. The number and size of tenons 6 and mortise 7 are determined according to the location being treated, with no less than 3 tenons 6 and no less than 2 mortise 7.

[0104] Figure 1 The diagram shows the unfolded shape of a human luminal stent. Figure 1 By bending in the direction indicated by the middle arrow, the human body lumen stent can be bent into a cylindrical structure.

[0105] The anti-displacement, self-adaptive, self-locking human endovascular stent is manufactured using micro-injection molding, and the process is as follows:

[0106] S1. Mold Design:

[0107] High-precision micro-injection mold (tolerance ±5μm) is used. The mold cavity contains a complete three-dimensional shape of support unit 1, connecting unit 2, connecting crossbeam 3, transition crossbeam 4, tenon crossbeam 5, tenon 6, and mortise 7.

[0108] S2, Material Injection and Molding:

[0109] When the support is made of metal: a biodegradable metal melt (such as magnesium alloy, melting temperature 650-700℃) is injected into the mold under high pressure, and after holding the pressure and cooling, it is demolded to form a complex metal support in one go.

[0110] When the support is made of polymer: PLGA or other materials melt (temperature 180-220℃) is injected into the mold, and rapid curing is achieved by controlling the mold temperature (cooling rate 10-20℃ / s);

[0111] S3. Demolding and self-locking calibration:

[0112] After demolding, a complete bracket is obtained directly. The tenon 6 and mortise 7 are precisely fitted by the mold to achieve an interference fit, requiring no additional processing.

[0113] S4. Deburring and surface finishing: Eliminate injection flow marks and parting lines through plasma etching (Ar / O2 mixed gas) or supercritical CO2 cleaning.

[0114] S5. Tenon 6 and mortise 7 fit calibration: Use an optical measurement system (such as a laser confocal microscope) to check the fit tolerance of tenon 6 and mortise 7. If necessary, adjust the slip space to ±0.01mm by local laser ablation or micro-injection molding.

[0115] Example 3: The anti-displacement adaptive self-locking human body cavity stent in this example includes a stent unit 1 and a connecting unit 2. Adjacent stent units 1 are connected through the connecting unit 2. The stent unit 1 includes a main frame with a rhomboid structure, and a connecting beam 3, a transition beam 4, and a tenon beam 5 disposed inside the main frame. The connecting beam 3, the transition beam 4, and the tenon beam 5 are connected in sequence. Both the connecting beam 3 and the tenon beam 5 are connected to the main frame. Each of the two tenon beams 5 is provided with multiple tenons 6. A mortise 7 is formed between adjacent tenons 6. The tenon 6 on one tenon beam 5 is connected to the mortise 7 on the other tenon beam 5. The number of tenons 6 is not less than 3, and the number of mortise 7 is not less than 2.

[0116] In this embodiment, the tenon 6 has a tenon front edge 61 and a tenon side edge 62 on both sides. The tenon front edge 61 is convex, and the tenon side edge 62 is convex or concave. The tenon groove 7 has a groove bottom edge 71, and there is a gap between the groove bottom edge 71 and the end of the tenon 6.

[0117] In this embodiment, the tenon beam 5 is designed with a slightly convex or slightly concave shape. The tenon 6 and the mortise 7 are fitted with a clearance, meaning that the tenon 6 can have a certain sliding space in the mortise 7, thereby achieving self-locking during the expansion of the stent. The connecting beam 3 is I-shaped, U-shaped, V-shaped, S-shaped, or M-shaped. The transition beam 4 is U-shaped or V-shaped and is used to connect the main frame between different stent units to ensure the continuity and stability of the overall stent structure. The connecting unit 2 is I-shaped, U-shaped, V-shaped, S-shaped, or M-shaped to ensure that the stent can adapt to the bending and dynamic changes of the lumen after implantation.

[0118] The working principle of this anti-displacement adaptive self-locking human body lumen stent is as follows:

[0119] Stent Expansion and Self-Locking: During stent implantation, the stent is expanded by a balloon, and the main frame of stent unit 1 deforms. Points A and B move away from each other, while points C and D move closer to each other, pushing the tenon 6 into the mortise 7 to form a self-locking structure. By adjusting the size of the mortise 7 along the circumference (i.e., the length of the bottom edge 71 of the groove), the range of motion of the stent in the self-locking state can be controlled to adapt to the contraction and relaxation of the lumen.

[0120] Adaptive adjustment: The tenon and mortise structure of the support (tenon 6 and mortise 7) adopts a clearance fit design, which allows for a certain amount of sliding space. When the lumen contracts or expands, the tenon 6 can slide in the mortise 7 to achieve adaptive adjustment of the support and ensure that the support is always in close contact with the lumen wall.

[0121] Degradation and absorption: The stent is made of biodegradable materials. After fulfilling its support function, the material gradually degrades and is absorbed by the body, avoiding the risk of removal by a second surgery.

[0122] In other words, during stent expansion, stent unit 1 deforms, points A and B move away from each other, and points C and D move closer to each other, causing tenon 6 to enter mortise 7, forming a self-locking structure. By adjusting the size of mortise 7 along the circumference, i.e. the length of the bottom edge 71 of the groove, the range of motion of the stent along the circumference under self-locking conditions can be adjusted to adapt to the contraction and dilation of lumens in certain locations, such as blood vessels. The number and size of tenons 6 and mortise 7 are determined according to the location being treated, with no less than 3 tenons 6 and no less than 2 mortise 7.

[0123] Figure 1 The diagram shows the unfolded shape of a human luminal stent. Figure 1 By bending in the direction indicated by the middle arrow, the human body lumen stent can be bent into a cylindrical structure.

[0124] The anti-displacement, self-adaptive, self-locking human endoscopic stent is manufactured using multi-material 3D printing in a single piece, and the process is as follows:

[0125] S1. Printing Technology Selection:

[0126] When the support is made of metal: Selective laser melting (SLM) technology is used, with magnesium alloy powder as the raw material, to melt and form it layer by layer;

[0127] When the scaffold is made of polymer: Fused deposition modeling (FDM) or digital light processing (DLP) are used, and PLGA wires or photosensitive resin are employed;

[0128] When the support is made of composite material: metal (powder) and polymer (melt) are printed simultaneously through a multi-nozzle system to achieve integrated processing of heterogeneous materials;

[0129] S2, Synchronous Structure Construction:

[0130] In the 3D model, support unit 1, connection unit 2, connecting beam 3, transition beam 4, tenon beam 5, tenon 6, and mortise 7 are predefined. The model is printed in one go through path planning. The gap (sliding space) between tenon 6 and mortise 7 is directly controlled by the printing accuracy (±0.02mm).

[0131] S3, In-situ Post-curing:

[0132] The metal support is annealed (300-400℃, argon atmosphere) to eliminate internal stress;

[0133] Polymer scaffolds enhance interlayer bonding through ultraviolet light (DLP) or thermosetting (FDM);

[0134] S4. Deburring and surface finishing: Chemical mechanical polishing (CMP) or ultrasonic microbead impaction (5μm particle size) is used to reduce surface roughness (Ra<0.1μm).

[0135] S5. Tenon 6 and mortise 7 fit calibration: Use an optical measurement system (such as a laser confocal microscope) to check the fit tolerance of tenon 6 and mortise 7. If necessary, adjust the slip space to ±0.01mm by local laser ablation or micro-injection molding.

[0136] Furthermore, it should be noted that the specific embodiments described in this specification may differ in the shape and name of their components, etc. The above description is merely illustrative of the structure of the present invention. All equivalent or simple variations made based on the structure, features, and principles described in this patent concept are included within the protection scope of this patent. Those skilled in the art can make various modifications or additions to the described specific embodiments or use similar methods to substitute them, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, all of which should fall within the protection scope of this invention.

Claims

1. A displacement-resistant, self-adaptive, self-locking human body lumen stent, comprising a stent unit (1) and a connecting unit (2), wherein adjacent stent units (1) are connected via the connecting unit (2), characterized in that: The support unit (1) includes a main frame arranged in a rhomboid structure, and a connecting beam (3), a transition beam (4) and a tenon beam (5) arranged inside the main frame. The connecting beam (3), the transition beam (4) and the tenon beam (5) are connected in sequence. The connecting beam (3) and the tenon beam (5) are both connected to the main frame. Multiple tenons (6) are provided on each of the two tenon beams (5). A mortise (7) is formed between adjacent tenons (6). The tenon (6) on one tenon beam (5) is connected to the mortise (7) on the other tenon beam (5). The tenon (6) and the mortise (7) are fitted with a clearance, that is, the tenon (6) has a certain sliding space in the mortise (7).

2. The anti-displacement adaptive self-locking human body lumen stent according to claim 1, characterized in that: The tenon (6) has a tenon front edge (61) and a tenon side edge (62) on both sides. The tenon front edge (61) is convex, and the tenon side edge (62) is convex or concave.

3. The anti-displacement adaptive self-locking human body lumen stent according to claim 1, characterized in that: The tenon (7) has a groove bottom edge (71) inside, and there is a gap between the groove bottom edge (71) and the end of the tenon (6).

4. The anti-displacement adaptive self-locking human body lumen stent according to claim 1, characterized in that: The tenon and mortise beam (5) is set in a convex or concave structure.

5. The anti-displacement adaptive self-locking human body lumen stent according to claim 1, characterized in that: The connecting beam (3) is of type I, U, V, S or M, the transition beam (4) is of type U or V, and the connecting unit (2) is of type I, U, V, S or M.

6. A method for manufacturing a displacement-resistant, self-adaptive, self-locking human endoscopic stent as described in any one of claims 1-5, characterized in that: The manufacturing method, which employs femtosecond laser integrated processing, is as follows: S1. Material pretreatment: Biodegradable metal sheets or polymer sheets are used as the substrate, and the surface is coated with a photosensitive resist. S2, femtosecond laser precision engraving: The substrate is directly cut by ultra-short pulse femtosecond laser to form a bracket unit (1), a connecting unit (2), a connecting beam (3), a transition beam (4), a tenon beam (5), a tenon (6), and a mortise (7) in one go; S3, In-situ forming mortise and tenon structure: Through laser path programming, tenons (6) and mortises (7) are directly carved while the main frame is being cut, leaving room for sliding and eliminating the need for secondary assembly; S4. Deburring and surface finishing: Low-power femtosecond laser scanning is used to cut the edges and remove micron-level burrs.

7. A method for manufacturing a displacement-resistant, self-adaptive, self-locking human endoscopic stent as described in any one of claims 1-5, characterized in that: The manufacturing method, which employs micro-injection molding, is as follows: S1. Mold Design: High-precision micro-injection molds are used. The mold cavity contains a complete three-dimensional shape of a support unit (1), a connecting unit (2), a connecting beam (3), a transition beam (4), a tenon beam (5), a tenon (6), and a mortise (7). S2, Material Injection and Molding: When the support is made of metal: biodegradable molten metal is injected into the mold under high pressure, and after holding the pressure and cooling, it is demolded to form a complex metal support in one go; When the support is made of polymer: PLGA material melt is injected into the mold, and rapid curing is achieved by controlling the mold temperature; S3. Demolding and self-locking calibration: After demolding, a complete bracket is obtained directly. The tenon (6) and mortise (7) are precisely fitted by the mold to achieve interference fit, without the need for additional processing. S4. Deburring and surface finishing: Eliminate injection flow marks and parting lines through plasma etching or supercritical CO2 cleaning.

8. A method for manufacturing a displacement-resistant, self-locking, self-adaptive human endoscopic stent as described in any one of claims 1-5, characterized in that: The manufacturing method, which involves multi-material 3D printing in a single integrated molding process, is as follows: S1. Printing Technology Selection: When the support structure is made of metal: selective laser melting technology is used, with magnesium alloy powder as the raw material, to melt and form layer by layer; when the support structure is made of polymer: fused deposition modeling or digital light processing is used, with PLGA wire or photosensitive resin; when the support structure is made of composite material: metal and polymer are printed simultaneously through a multi-nozzle system to achieve integrated integration of heterogeneous materials. S2, Synchronous Structure Construction: In the 3D model, predefine the support unit (1), connection unit (2), connection beam (3), transition beam (4), tenon beam (5), tenon (6), and mortise (7), and print them in one go through path planning. The gap between the tenon (6) and mortise (7) is directly controlled by the printing accuracy. S3, In-situ Post-curing: The metal support structure is annealed to eliminate internal stress; Polymer scaffolds are enhanced through ultraviolet light or thermosetting to improve interlayer bonding; S4. Deburring and surface finishing: Chemical mechanical polishing or ultrasonic microbead impaction is used to reduce surface roughness.

9. The method for manufacturing the anti-displacement adaptive self-locking human body lumen stent according to claims 6-8, characterized in that: The tenon (6) and mortise (7) are aligned and aligned: The fit tolerance between the tenon (6) and the mortise (7) was tested using an optical measurement system.

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