Conveying assembly and conveying system

Abstract

The invention provides a conveying assembly and a conveying system. The conveying assembly comprises a conveying guide wire, a pushing element and a withdrawing element. The conveying guide wire is sleeved with the pushing element and the withdrawing element, the pushing element and the withdrawing element are arranged at intervals in the axial direction of the conveying guide wire, and the distance from the pushing element to the far end of the conveying guide wire is larger than the distance from the withdrawing element to the far end of the conveying guide wire; the withdrawing element is provided with a variable-diameter part, the variable-diameter part is arranged at the end of the withdrawing element, and the diameter of the variable-diameter part is gradually reduced in the direction away from the center of the withdrawing element. According to the configuration, the inclination of the reducing part enables the far-end port of the micro catheter to smoothly pass through the part between the pushing element and the withdrawing element when the conveying guide wire is recycled, so that the risk that the withdrawing element is clamped at the far-end port of the micro catheter and the conveying guide wire cannot be recycled is avoided; meanwhile, due to the inclination of the reducing part, the withdrawing element cannot hook the meshes of the stent body, and the risk that the stent body shifts in the withdrawing process of the conveying guide wire is avoided.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to a delivery component and a delivery system. Background Art

[0002] Vascular diseases, such as cerebrovascular diseases, are one of the major diseases that threaten human life and health today, and interventional treatment methods have become the standard method for treating the disease. Interventional treatments are usually designed to deliver stents (such as self-expanding stents) to the lesion site through a delivery system. Existing stent-guidewire combinations include a snap-fit ​​structure, a membrane structure, and a braided expansion structure. The snap-fit ​​structure locks the developing ring at one end of the stent through a push element and a retraction element on the delivery guide wire, thereby achieving the pushing and retraction of the stent in the microcatheter. However, there is a gap between the push element and the retraction element. After the stent is released, the guide wire is retracted, and the microcatheter port is easily stuck between the push element and the retraction element, resulting in the risk that the delivery guide wire cannot be recovered; in addition, the retraction element on the delivery guide wire will also hang on the stent mesh, causing the stent to shift when the delivery guide wire is retracted. Summary of the invention

[0003] The purpose of the present invention is to provide a delivery assembly and a delivery system to solve the problem that the microcatheter port and the elements on the delivery guidewire are stuck, resulting in the delivery guidewire being unable to be recovered, and the elements on the delivery guidewire being caught on the stent mesh, resulting in the stent being displaced.

[0004] In order to achieve the above-mentioned object, the present invention provides a delivery assembly, comprising: a delivery guide wire, a pushing element and a retracting element;

[0005] The pushing element and the retracting element are both sleeved outside the delivery guide wire, the pushing element and the retracting element are spaced apart along the axial direction of the delivery guide wire, and the distance from the pushing element to the distal end of the delivery guide wire is greater than the distance from the retracting element to the distal end of the delivery guide wire;

[0006] The pushing element is used to drive the stent body to move in a direction close to the distal end of the delivery guide wire, and the retracting element is used to drive the stent body to move in a direction away from the distal end of the delivery guide wire;

[0007] The retraction element has a diameter-reducing portion, which is arranged at an end of the retraction element, and a diameter of the diameter-reducing portion gradually decreases in the axial direction of the delivery guide wire in a direction away from the center of the retraction element.

[0008] Optionally, a developing member is provided at the end of the support body, and the pushing member and the retracting member respectively abut against the developing member to drive the support body to move along the axial direction of the conveying guide wire.

[0009] Optionally, the developing parts are provided at both ends of the support body along the axial direction of the conveying guide wire, and the retraction element is movable between or outside the developing parts at both ends.

[0010] Optionally, the length of the reducing portion along the axial direction of the delivery guide wire is L, the slope of the reducing portion is α, and the outer diameter of the retraction element is D, satisfying L=D / (2tanα).

[0011] Optionally, 20°≤α≤70°.

[0012] Optionally, an abutment platform is provided at the connection between the diameter reducing portion and the retracting element. The abutment platform is provided along the circumferential outer edge of the retracting element. The abutment platform is used to abut against the developing member when the retracting element drives the bracket body to move.

[0013] Optionally, the thickness of the abutment platform along the radial direction of the delivery guide wire is N, and the outer diameter of the retraction element is D, satisfying 0<N≤0.5D.

[0014] Optionally, the developing member is a spherical member, the radius of the developing member is M, the inner diameter of the bracket body after compression is C, and 0.5C≤M≤C is satisfied.

[0015] Optionally, the retraction element has two diameter-reducing portions, and the two diameter-reducing portions are respectively arranged at two ends of the retraction element along the axial direction of the delivery guide wire.

[0016] Optionally, the material of the retractable element includes metal material, polymer material, and ceramic material.

[0017] In order to achieve the above object, the present invention also provides a delivery system, comprising: a microcatheter, a stent body and the delivery assembly as described above;

[0018] The stent body is sleeved on the delivery guide wire and covers the withdrawal element;

[0019] The micro-catheter has an inner cavity which penetrates along its own axial direction, and the inner cavity is used for the delivery component to be movably arranged therein.

[0020] In summary, in the delivery assembly and delivery system proposed in the present invention, the delivery assembly includes: a delivery guidewire, a pushing element and a retraction element; the pushing element and the retraction element are both sleeved on the delivery guidewire, the pushing element and the retraction element are spaced apart along the axial direction of the delivery guidewire, and the distance from the pushing element to the distal end of the delivery guidewire is greater than the distance from the retraction element to the distal end of the delivery guidewire; the pushing element is used to drive the stent body to move in a direction close to the distal end of the delivery guidewire, and the retraction element is used to drive the stent body to move in a direction away from the distal end of the delivery guidewire; wherein the retraction element has a reducing portion, the reducing portion is arranged at the end of the retraction element, and the diameter of the reducing portion gradually decreases in the axial direction of the delivery guidewire along a direction away from the center of the retraction element. Compared with the existing delivery assemblies, the present application has the following advantages:

[0021] (1) The retraction element has a reducing portion disposed at the end thereof, and the diameter of the reducing portion gradually decreases in the direction away from the center of the retraction element in the axial direction of the delivery guidewire. The inclination of the reducing portion enables the distal end port of the microcatheter to smoothly pass through the portion between the pushing element and the retraction element when the delivery guidewire is retracted, thereby avoiding the risk of the retraction element being stuck at the distal end port of the microcatheter, resulting in the inability to retract the delivery guidewire. At the same time, the inclination of the reducing portion prevents the retraction element from getting caught on the mesh of the stent body, thereby avoiding the risk of the stent body shifting during the retraction of the delivery guidewire.

[0022] (2) A stopper is provided at the connection between the reducing portion and the retracting element, and the stopper is used to abut against the developing element when the retracting element drives the stent body to move, thereby ensuring that the stent body will not be unloaded from the conveying guide wire during the retracting process; at the same time, the developing element abuts against the stopper, so that the developing element will not exert a radially outward expansion force during the retracting process, thereby increasing the retracting resistance;

[0023] (3) The two reducing portions are respectively arranged at the two ends of the retraction element along the axial direction of the delivery guide wire, thereby ensuring that the retraction element will not puncture the blood vessel and cause unnecessary damage during the process of releasing the stent body or retrieving the delivery guide wire. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of a conveying assembly in the prior art;

[0025] Figure 2 It is a schematic diagram of a withdrawal element in the prior art being stuck in the distal end port of a microcatheter;

[0026] Figure 3 A schematic diagram and a cross-sectional diagram of a first retractable element proposed in an embodiment of the present invention;

[0027] Figure 4A schematic diagram of a case where the slope of the reducing portion of the first retractable element proposed in an embodiment of the present invention is too large;

[0028] Figure 5 A schematic diagram of a first type of retractable element when the slope of the reducing portion is too small, according to an embodiment of the present invention;

[0029] Figure 6 A schematic diagram and a cross-sectional diagram of a second retractable element provided by an embodiment of the present invention;

[0030] Figure 7 A structural cross-sectional view of a developing ring proposed in an embodiment of the present invention.

[0031] The description of each reference numeral is as follows:

[0032] 1- retracting element; 11- reducing portion; 12- abutting platform; 13- through hole;

[0033] 2- pushing element; 3- delivery guide wire; 4- stent body; 5- developing part; 6- microcatheter. DETAILED DESCRIPTION

[0034] In order to make the purpose, advantages and features of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis of each drawing is different, and sometimes different scales are used.

[0035] As used in this specification, the singular forms "one", "an" and "the" include plural objects, the term "or" is generally used to include the meaning of "and / or", the term "several" is generally used to include the meaning of "at least one", and the term "at least two" is generally used to include the meaning of "two or more". In addition, the terms "first", "second" and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second" and "third" may explicitly or implicitly include one or at least two of the features, "one end" and "the other end" and "proximal end" and "distal end" generally refer to two corresponding parts, which not only include the endpoints, wherein the "proximal end" generally represents the direction close to the doctor during the operation, and the "distal end" generally represents the direction close to the lesion during the operation. The terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral body; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. In addition, as used in this specification, an element disposed on another element generally only indicates that there is a connection, coupling, cooperation or transmission relationship between the two elements, and the connection, coupling, cooperation or transmission between the two elements may be direct or indirect through an intermediate element, and it cannot be understood as indicating or implying the spatial position relationship between the two elements, that is, one element may be in any orientation such as inside, outside, above, below or on one side of another element, unless the content clearly indicates otherwise. The terms "upper", "lower", "top" and "bottom" are generally relative position relationships arranged in the direction of gravity; the terms "vertical, vertical direction" generally refer to the direction of gravity, which is generally perpendicular to the ground, and "horizontal, horizontal plane direction" generally refers to the direction parallel to the ground; for ordinary technicians in this field, the specific meanings of the above terms in this specification can be understood according to specific circumstances.

[0036] The purpose of the present invention is to provide a delivery assembly and a delivery system to solve the problem that the microcatheter port and the elements on the delivery guidewire are stuck, resulting in the delivery guidewire being unable to be recovered, and the elements on the delivery guidewire being caught on the stent mesh, resulting in the stent being displaced.

[0037] Please refer to Figure 1 to Figure 2 Currently, the delivery method of the self-expanding stent body 4 is mostly a snap-fit ​​structure, such as Figure 1As shown, it mainly places the developing member 5 located at the proximal end of the stent body 4 between the retraction member 1 and the pushing member 2 on the conveying guide wire 3. When the stent body 4 is retracted toward the proximal end, the retraction member 1 located inside the stent body 4 clamps the inner side of the developing member 5 and moves toward the proximal end of the conveying guide wire 3; when the stent body 4 is pushed toward the distal end, the pushing member 2 on the conveying guide wire 3 clamps the outer side of the developing member 5 and moves toward the distal end of the conveying guide wire 3. Since the retraction element 1 is located inside the stent body 4, when the stent body 4 is released, when the delivery guide wire 3 is retracted, there is a certain probability that the retraction element 1 will be stuck in the mesh of the stent body 4 or the wave rod of the open-loop stent body 4, thereby causing the stent body 4 to be dragged, causing the stent body 4 to shift and affect the treatment effect; in addition, when the stent body 4 is released, the delivery guide wire 3 will be fixed, and the microcatheter 6 will be pushed toward the distal end along the delivery guide wire 3 until the entire delivery guide wire 3 is withdrawn into the microcatheter 6; or, affected by the blood vessel structure, when the microcatheter 6 cannot continue to move toward the distal end of the delivery guide wire 3, it can also be driven to move toward the proximal end until the delivery guide wire 3 is completely withdrawn into the microcatheter 6, such as Figure 2 As shown, since the withdrawal element 1 and the pushing element have a certain distance along the axial direction of the delivery guidewire 3, the distal port of the microcatheter 6 is often stuck at the proximal end of the withdrawal element 1, resulting in the inability to completely withdraw the delivery guidewire 3 into the microcatheter 6. Based on this, the delivery assembly provided by the present invention, by providing a reducing portion 11 with an inclination at the end of the withdrawal element 1, will not get stuck in the mesh of the stent body 4 or the distal port of the microcatheter 6 during the withdrawal of the delivery guidewire 3, thereby avoiding the risk of displacement of the stent body 4 or inability to recover the delivery guidewire 3. It should be noted that this application only takes the delivery stent body 4 as an example for explanation, and its structure can also be applied to other components that need to be coated in the delivery assembly and transported, such as prostheses, etc. As long as it needs to be coated in the delivery assembly for transportation, the structure of this application can be adopted.

[0038] Please refer to Figure 1 and Figure 3 The present invention provides a delivery assembly, including: a delivery guide wire 3, a pushing element 2 and a retraction element 1; the pushing element 2 and the retraction element 1 are both sleeved outside the delivery guide wire 3, the pushing element 2 and the retraction element 1 are spaced apart along the axial direction of the delivery guide wire 3, and the distance from the pushing element 2 to the distal end of the delivery guide wire 3 is greater than the distance from the retraction element 1 to the distal end of the delivery guide wire 3; the pushing element 2 is used to drive the stent body 4 to move in the direction close to the distal end of the delivery guide wire 3, and the retraction element 1 is used to drive the stent body 4 to move in the direction close to the proximal end of the delivery guide wire 3; wherein the retraction element 1 has a reducing portion 11, the reducing portion 11 is arranged at the end of the retraction element 1, and the diameter of the reducing portion 11 gradually decreases in the axial direction of the delivery guide wire 3 along the direction away from the center of the retraction element 1. It should be noted that the axial direction of the delivery guide wire 3 is Figure 3The left and right directions are shown in the middle, and the radial direction of the conveying guide wire 3 is Figure 3 The retraction element 1 has a through hole 13 extending along its own axial direction, and the through hole 13 is used for passing the guide wire 3 through the conveying guide wire 3. Figure 3 In the illustrated example, the outer diameter of the reducing portion 11 is gradually reduced from the outer diameter of the withdrawal element 1 to the diameter of the through hole 13, and forms a slope; the reducing portion 11 and the withdrawal element 1 can be integrally arranged, or cylindrical, and the reducing portion 11 is formed by soldering, dispensing, etc.; in some other embodiments, the reducing portion 11 can also be in the shape of an arc surface, and the arc surface is convex in the direction away from the withdrawal element 1, the maximum outer diameter of the reducing portion 11 can also be smaller than the outer diameter of the withdrawal element 1, and the minimum outer diameter of the reducing portion 11 can also be greater than the diameter of the through hole 13, as long as the diameter of the reducing portion 11 is gradually reduced in the axial direction of the delivery guide wire 3 in the direction away from the center of the withdrawal element 1. In this configuration, the reducing portion 11 with an inclination makes it possible that during the process of retrieving the delivery guide wire 3, the end of the withdrawal element 1 will not hang on the mesh of the stent body 4, and will not be stuck at the distal port of the microcatheter 6, reducing the jamming during the process of retrieving the delivery guide wire 3, improving the practical performance of the delivery assembly, and also improving the safety of the entire surgical process.

[0039] Furthermore, a developing member 5 is provided at the end of the stent body 4, and the pushing member 2 and the retracting member 1 can respectively abut against the developing member 5 to drive the stent body 4 to move along the axial direction of the delivery guide wire 3. It should be noted that the developing member 5 is provided at the end of the stent body 4, which can help the operator to monitor the position of the stent body 4 in real time; at the same time, when the delivery guide wire 3 is recovered, it is also possible to monitor in real time whether the stent body 4 is displaced, and then timely handle it to ensure the success of the operation.

[0040] Furthermore, both ends of the stent body 4 along the axial direction of the delivery guide wire 3 are provided with developing parts 5, and the retraction element 1 is movable between or outside the developing parts 5 at both ends. Those skilled in the art can understand that the positions of the pushing element 2 and the retraction element 1 relative to the delivery guide wire 3 are fixed, and when it is necessary to push the stent body 4 toward the distal end of the delivery guide wire 3, the operator drives the delivery guide wire 3 to move toward the distal end so that the pushing element 2 abuts against the developing part 5 at the proximal end of the stent, thereby driving the stent body 4 to be pushed toward the distal end; when it is necessary to retract the stent body 4 toward the proximal end of the delivery guide wire 3, the operator drives the delivery guide wire 3 to move toward the proximal end so that the retraction element 1 abuts against the developing part 5 at the proximal end of the stent (such as Figure 1As shown), the stent body 4 is driven to withdraw toward the proximal end. Of course, in other embodiments, the developing member 5 may also be disposed only at the proximal end of the stent body 4; the withdrawing element 1 may also be placed on the outside of the developing member 5 at the distal end. At this time, when it is necessary to withdraw the stent body 4 toward the proximal end of the delivery guide wire 3, the operator drives the delivery guide wire 3 to move toward the proximal end so that the withdrawing element 1 abuts against the developing member 5 at the distal end of the stent, thereby realizing the withdrawal of the stent body 4. Those skilled in the art may configure this according to actual conditions.

[0041] In an optional embodiment, the length of the reducing portion 11 along the axial direction of the delivery guide wire 3 is L, the slope of the reducing portion 11 is α, and the outer diameter of the retracting element 1 is D, satisfying L=D / (2tanα). Figure 3 For example, the retraction element 1 can be considered to be composed of a cylinder plus a reducing portion 11, the outer diameter D of the retraction element 1 is the diameter of the cylinder, the slope α of the reducing portion 11 is the angle between the outer wall of the reducing portion 11 and the axial direction of the delivery guidewire 3, and the length L of the reducing portion 11 along the axial direction of the delivery guidewire 3 is the projected length of the outer wall of the reducing portion 11 along the axial direction of the delivery guidewire 3. Further, 20°≤α≤70°, preferably 35°≤α≤60°. When the push element 1 is completely exposed to the outside of the microcatheter 6, if the retraction element 1 is retracted into the microcatheter 6, the slope of the reducing portion 11 at 35° to 60° can ensure that the distal port of the microcatheter 6 passes smoothly along the reducing portion 11 at the distal end of the retraction element 1, and will not be stuck between the retraction element 1 and the push element 2. In addition, when the stent body 4 is in the process of being transported, the developing member 5 is located between the retracting member 1 and the pushing member 2, and the outer periphery of the stent body 4 is restricted by the inner wall of the microcatheter 6; when the stent body 4 is pushed or retracted when the inclination of the reducing portion 11 is between 35° and 60°, the developing member 5 is subjected to the axial force along the transport guide wire 3, so that the developing member 5 will not be unloaded from between the retracting member 1 and the pushing member 2.

[0042] Please refer to Figures 4 to 5 When α is between 70° and 90°, during the process of withdrawing the delivery guide wire 3, the distal end of the microcatheter 6 will still be stuck at the proximal end of the withdrawable element 1 (e.g. Figure 4 When α is between 0° and 20°, during the process of withdrawing the delivery guide wire 3, the distal end of the microcatheter 6 will not be stuck at the proximal end of the withdrawal element 1, but the diameter reducing portion 11 with a smaller slope will exert a driving force on the developing member 5 to a large extent, so that the developing member 5 is subjected to a large outward radial force (such as Figure 5 As shown), the developing member 5 and the retracting member 1 are unloaded.

[0043] In another optional embodiment, please refer to Figure 6A contact platform 12 is provided at the connection between the diameter reducing portion 11 and the retracting element 1. The contact platform 12 is provided along the circumferential outer edge of the retracting element 1. The contact platform 12 is used to contact the developing element 5 when the retracting element 1 drives the bracket body 4 to move. Figure 6 For example, the abutment platform 12 is a plane arranged along the radial direction of the conveying guide wire 3. It can abut against the developing part 5 during the process of withdrawing the bracket body 4, thereby ensuring that the bracket body 4 is not unloaded and no radial outward force is applied to the developing part 5, thereby reducing the pushing resistance.

[0044] Furthermore, the thickness of the abutment platform 12 along the radial direction of the delivery guide wire 3 is N, and the outer diameter of the retracting element 1 is D, which satisfies 0<N≤0.5D, preferably 0.1D≤N≤0.3D. It can be understood by those skilled in the art that the developing member 5 is distributed along the inner wall of the microcatheter 6, and the space between two adjacent developing members 5 is hollow, and the developing member 5 is only in contact with the outer edge portion of the retracting element 1 (at Figure 6 When N is between 0.1D and 0.3D, the stent body 4 will not be unloaded, and the retraction element 1 will not be stuck at the distal end port of the microcatheter 6.

[0045] In some other embodiments, the developing member 5 is a spherical member, the radius of the developing member 5 is M, the inner diameter of the bracket body 4 after compression is C, and 0.5C≤M≤C is satisfied, preferably 0.7C≤M≤0.9C. Figure 1 and Figure 5 In the illustrated example, the developing member 5 is a rectangular parallelepiped or cylindrical member. In some other examples, the developing member 5 may also be a spherical member (eg, Figure 7 As shown), the inner diameter C of the stent body 4 after compression is the radius of the annular cross-section formed by the inner surface of the stent body 4 after compression. Of course, in other embodiments, the radius of the developing member 5 may also be within other reasonable numerical ranges. Those skilled in the art may configure the size of the developing member 5 according to the diameter of the microcatheter 6 and the structure of the blood vessel.

[0046] As a preferred embodiment, the retraction element 1 has two reducing portions 11, which are respectively arranged at the two ends of the retraction element 1 along the axial direction of the delivery guide wire 3. In this configuration, both ends of the retraction element 1 along the axial direction of the delivery guide wire 3 are provided with reducing portions 11, so that the delivery component will not puncture the blood vessel during the process of delivering the stent body 4 to the distal end or retrieving the delivery guide wire 3 to the proximal end, thereby avoiding unnecessary damage.

[0047] In an alternative embodiment, the material of the retracting element 1 includes metal materials, polymer materials, and ceramic materials. It should be noted that the retracting element 1 can be one or more of titanium, nickel-titanium alloy, stainless steel, platinum-tungsten alloy, platinum, platinum-iridium alloy, and cobalt-chromium alloy; it can also be platinum, iridium, tantalum, precious metal alloy, and other materials with developability; it can also be polymer materials, ceramic materials, etc. Those skilled in the art can configure the material of the retracting element 1 according to actual conditions.

[0048] The present invention also provides a delivery system, comprising: a microcatheter 6, a stent body 4 and the above delivery assembly; the stent body 4 is sleeved on the delivery guide wire 3 and covers the withdrawal element 1; the microcatheter 6 has an inner cavity that penetrates along its own axis, and the inner cavity is used for the delivery assembly to be movably installed. Figure 1 and Figure 5 When the delivery system is in the delivery process, the delivery component and the stent body 4 are both in the inner cavity of the microcatheter 6; when the delivery system delivers the stent body 4 to the target position, the operator can drive the delivery guide wire 3 to move distally, so that the pushing element 2 abuts against the developing element 5 at the proximal end of the stent body 4, thereby driving the stent body 4 to move distally until it is completely disengaged from the distal end port of the microcatheter 6 and the release is completed; during the process of releasing the stent body 4, if it is found that there is an error in the position of the stent body 4, the operator can drive the delivery guide wire 3 to move proximally, The retraction element 1 is made to abut against the developing element 5 at the proximal end of the stent body 4, thereby driving the stent body 4 to move proximally until it completely penetrates from the distal port of the microcatheter 6 to complete the retraction; after the stent body 4 is released, the operator can drive the microcatheter 6 to move distally until the delivery guide wire 3 completely penetrates from the distal port of the microcatheter 6; in the process of recovering the delivery guide wire 3, if the microcatheter 6 cannot continue to move distally due to the influence of the blood vessel structure, the operator can also directly drive the delivery guide wire 3 to move proximally until the recovery of the delivery guide wire 3 is completed.

[0049] In summary, in the delivery component and delivery system provided in the embodiments of the present invention, the delivery component includes: a delivery guide wire, a pushing element and a retraction element; the pushing element and the retraction element are both sleeved on the delivery guide wire, the pushing element and the retraction element are spaced apart along the axial direction of the delivery guide wire, and the distance from the pushing element to the distal end of the delivery guide wire is greater than the distance from the retraction element to the distal end of the delivery guide wire; the pushing element is used to drive the stent body to move in a direction close to the distal end of the delivery guide wire, and the retraction element is used to drive the stent body to move in a direction away from the distal end of the delivery guide wire; wherein the retraction element has a reducing portion, the reducing portion is arranged at the end of the retraction element, and the diameter of the reducing portion gradually decreases in the axial direction of the delivery guide wire along the direction away from the center of the retraction element.

[0050] With such configuration, the retraction element has a reducing portion arranged at the end, and the diameter of the reducing portion gradually decreases in the axial direction of the delivery guidewire in the direction away from the center of the retraction element. The inclination of the reducing portion enables the distal end port of the microcatheter to smoothly pass through the portion between the pushing element and the retraction element when the delivery guidewire is retracted, thereby avoiding the risk of the retraction element being stuck at the distal end port of the microcatheter, resulting in the inability to retract the delivery guidewire. At the same time, the inclination of the reducing portion prevents the retraction element from hanging on the mesh of the stent body, thereby avoiding the risk of the stent body shifting during the retraction of the delivery guidewire.

[0051] Furthermore, a stopper is provided at the connection between the reducing portion and the retracting element, and the stopper is used to abut against the developing element when the retracting element drives the stent body to move, thereby ensuring that the stent body will not be unloaded from the conveying guide wire during the retracting process; at the same time, the developing element abuts against the stopper, so that the developing element will not exert a force that expands radially outward during the retracting process, thereby increasing the retracting resistance;

[0052] Furthermore, the two diameter reducing parts are respectively arranged at the two ends of the withdrawal element along the axial direction of the delivery guide wire, ensuring that the withdrawal element will not puncture the blood vessel and cause unnecessary damage during the process of releasing the stent body or retrieving the delivery guide wire.

[0053] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A conveying assembly, characterized in that: include: Delivery guidewire, push element, and retrieval element; The pushing element and the retracting element are both sleeved outside the delivery guide wire, the pushing element and the retracting element are spaced apart along the axial direction of the delivery guide wire, and the distance from the pushing element to the distal end of the delivery guide wire is greater than the distance from the retracting element to the distal end of the delivery guide wire; The pushing element is used to drive the stent body to move in a direction close to the distal end of the delivery guide wire, and the retracting element is used to drive the stent body to move in a direction away from the distal end of the delivery guide wire; The retracting element has a diameter-changing portion, which is arranged at the end of the retracting element, and the diameter of the diameter-changing portion gradually decreases in the axial direction of the conveying wire in a direction away from the center of the retracting element.

2. The conveying assembly according to claim 1, characterized in that A developing member is disposed at the end of the support body, and the pushing member and the retracting member respectively abut against the developing member to drive the support body to move along the axial direction of the conveying guide wire.

3. The conveying assembly according to claim 2, characterized in that The developing parts are arranged at both ends of the support body along the axial direction of the conveying guide wire, and the retracting element is movable between or outside the developing parts at the two ends.

4. The conveying assembly according to claim 2, characterized in that The length of the diameter-changing portion along the axial direction of the delivery guide wire is L, the slope of the diameter-changing portion is α, and the outer diameter of the retraction element is D, satisfying L=D / (2tanα).

5. The conveying assembly according to claim 4, characterized in that 20°≤α≤70°。 6. The conveying assembly according to claim 2, characterized in that A contact platform is provided at the connection between the diameter reducing portion and the retracting element. The contact platform is provided along the circumferential outer edge of the retracting element. The contact platform is used to contact the developing member when the retracting element drives the bracket body to move.

7. The conveying assembly according to claim 6, characterized in that The thickness of the abutment platform along the radial direction of the delivery guide wire is N, and the outer diameter of the retraction element is D, satisfying 0<N≤0.5D.

8. The conveying assembly according to claim 2, characterized in that The developing member is a spherical member, the radius of the developing member is M, the inner diameter of the bracket body after compression is C, and 0.5C≤M≤C is satisfied.

9. The conveying assembly according to claim 1, characterized in that The retractable element has two diameter-reducing portions, and the two diameter-reducing portions are respectively arranged at two ends of the retractable element along the axial direction of the delivery guide wire.

10. The conveying assembly according to claim 1, characterized in that The material of the retractable element includes metal material, polymer material and ceramic material.

11. A conveying system, characterized in that: include: A microcatheter, a stent body, and a delivery assembly as claimed in any one of claims 1 to 10; The stent body is sleeved on the delivery guide wire and covers the withdrawal element; The micro-catheter has an inner cavity which penetrates along its own axial direction, and the inner cavity is used for the delivery component to be movably arranged therein.

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