Unlocking method and delivery system

Abstract

The application discloses an unlocking method for unlocking a loop shrink device of a delivery system, the loop shrink device comprising an anchor body (110) and a limiting part (132) arranged at the proximal end of the anchor body, wherein a limiting ring (121) is arranged at the proximal end of the anchor body; the unlocking method comprises the following steps: pushing a push rod in the distal direction, accommodating the limiting part into a cavity (310) of the push rod, and making the limiting ring (121) tightly contact with the side wall of the push rod; by pulling the limiting ring (121) or by pushing the limiting part (132), the limiting ring (121) is separated from the limiting part (132); and thus the unlocking at the proximal end of the loop shrink device is completed; by using the unlocking method, the loop shrink device can be unlocked at the proximal end of the loop shrink device, the loop shrink device is in a shrink state, and the repositioning and recycling of the loop shrink device are facilitated. The application further discloses a delivery system.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of interventional medical devices, and in particular to a method of unlocking, and a delivery system capable of applying the method of unlocking. BACKGROUND

[0002] This section provides background information only and can not necessarily be prior art.

[0003] The mitral valve is a part of the heart, between the left atrium and the left ventricle. Blood is pumped from the left atrium into the left ventricle, and when the left ventricle contracts to pump blood into the body, the mitral valve closes to prevent blood from being pumped back into the left atrium. In some patients, either due to genetic malformation, disease, or injury, the mitral valve does not close properly, resulting in a condition known as regurgitation, in which blood is pumped into the atrium with each contraction of the heart muscle. Regurgitation is a serious, often rapidly worsening condition that reduces the efficiency of circulation and must be corrected.

[0004] Mitral valve disease is the leading heart valve disease. Heart valves are divided into mitral valve, tricuspid valve, aortic valve and pulmonary valve according to their own morphology and location. Morphologically and functionally normal valves can act as "one-way valves" to ensure that blood flow in the heart can only flow in a fixed single direction without backflow. If the valve is abnormal in structure, function degeneration or other diseases, it will appear stenosis or insufficiency, which will affect the normal flow of blood in the heart, and will progressively lead to abnormal heart function, and eventually cause heart failure. Among all heart valve diseases, mitral valve disease is the disease type with the highest prevalence; according to Frost Sullivan data, the proportion of mitral valve disease patients in the world and China accounted for 53.0% and 45.2% of all valve diseases in 2019, respectively, much higher than the proportion of aortic valve patients in all valve diseases (25.1% in the world, 22.6% in China).

[0005] Two common methods to repair damaged mitral valve function are to replace the mitral valve with a mechanical valve through surgery, or to sew a flexible ring around the mitral valve to support the mitral valve. These surgeries are highly invasive, as they require access to the heart through an opening in the patient's chest. Mitral valve regurgitation patients are often relatively fragile, thus increasing the risk of surgery.

[0006] Now through minimally invasive surgery treatment, is most heart valve disease is more optimal choice, the main intervention treatment way artificial chordae tendineae implantation, mitral valve annuloplasty and mitral valve edge to edge repair, etc. Among them, annuloplasty has direct annuloplasty and indirect annuloplasty two. Indirect annuloplasty is mainly to tighten the blood vessel tissue around the mitral valve ring to achieve the purpose of shrinking the mitral valve ring, so that the mitral valve leaflet closes tightly. Coronary sinus-cardiac vein is mainly the blood vessel around the mitral valve ring, which also makes it the best implantation object of indirect annuloplasty.

[0007] However, for the implanted ring shrinkage device, there is no good method for repositioning and recycling the ring shrinkage device in the prior art, which adversely affects minimally invasive surgery. SUMMARY

[0008] Based on this, the application provides an unlocking method, which can unlock the proximal end of the ring shrinkage device, so that the ring shrinkage device is in a contracted state, which is beneficial to the repositioning and recycling of the ring shrinkage device. The application also provides a delivery system which can use the unlocking method to unlock the proximal end of the ring shrinkage device.

[0009] To achieve this purpose, the application adopts the following technical solutions:

[0010] The first aspect of the application provides an unlocking method, which is suitable for a delivery system to unlock a ring shrinkage device. The ring shrinkage device includes an anchor body and a limiting part at the proximal end of the anchor body, wherein a limiting ring is provided at the proximal end of the anchor body. The delivery system includes a push rod, a connecting tube, a first traction member and a third traction member. The connecting tube is provided in the cavity of the push rod, and the cavity of the push rod can accommodate the limiting part and the limiting ring. The first traction member is provided in the inner cavity of the connecting tube and is detachably connected with the limiting part. Under the action of the first traction member, the limiting part abuts against the pipe opening of the connecting tube, and the third traction member is connected with the limiting ring.

[0011] The unlocking method includes:

[0012] Push the push rod in the distal direction, accommodate the limiting part into the cavity of the push rod, and make the limiting ring tightly adhere to the side wall of the push rod; by pulling the limiting ring or by pushing the limiting part, the limiting ring is separated from the limiting part; the proximal end of the ring shrinkage device is unlocked.

[0013] The unlocking method can unlock the proximal end of the ring shrink device; in the unlocking method, the limiting ring is separated from the limiting part after the limiting part is accommodated into the cavity of the push rod, and the unlocking is completed; the limiting ring can be pulled, and the limiting ring is separated from the limiting part under the action of the continuous pulling force; the limiting part can also be pushed to the other side of the limiting ring, the limiting ring is separated from the limiting part, and the unlocking is completed.

[0014] In some embodiments of the unlocking method, the limiting part (132) is accommodated into the cavity (310) of the push rod (300) through the inner chamfer of the cavity (310).

[0015] In some embodiments of the unlocking method, the limiting ring (121) is separated from the limiting part (132) under the elastic force of the third traction member (430) on the limiting ring (121).

[0016] In some embodiments of the unlocking method, the push rod (300) and the third traction member (430) are simultaneously moved axially in the proximal direction, and the limiting ring (121) is separated from the limiting part (132) under the elastic force of the third traction member (430) on the limiting ring (121).

[0017] In some embodiments of the unlocking method, the connecting pipe (700) is moved in the distal direction until the limiting part (132) abutting against the connecting pipe (700) is pushed to the other side of the limiting ring (121), so that the limiting ring (121) is separated from the limiting part (132).

[0018] In some embodiments of the unlocking method, the relative position of the limiting ring (121) and the push rod (300) does not change under the action of the third traction member (430).

[0019] In some embodiments of the unlocking method, the axial movement of the push rod (300) is controlled by rotating the push rod controller in the conveying system.

[0020] In some embodiments of the unlocking method, the axial movement of the third traction member (430) is controlled by pulling the pull rod (541) in the conveying system.

[0021] In some embodiments of the unlocking method of the present application, the pull rod (541) in the delivery system is moved to the first position (551) of the pull rod guide (543), and the third traction member (430) connected to the pull rod (541) provides an elastic force to the limiting ring (121).

[0022] In some embodiments of the unlocking method of the present application, the pull rod (541) in the delivery system is moved to the first position (551) of the pull rod guide (543), and under the action of the third traction member (430) connected to the pull rod (541), the relative position of the limiting ring (121) and the push rod (300) remains unchanged.

[0023] The unlocking method provided by the present application can also solve the technical problems that the direction of the traction force of the third traction member 430 on the limiting ring 121 is inconsistent with the direction of the limiting ring 121 disengaging from the limiting portion 132, causing unlocking failure, and the arching between the connecting tube and the push rod when unlocking the ring shrinkage device. The unlocking method provided by the present application can smoothly unlock the ring shrinkage device in the body and achieve good technical effects.

[0024] The second aspect of the present application provides a delivery system capable of unlocking the ring shrinkage device by using the unlocking method described above. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 A schematic view of the limiting ring failing to disengage from the limiting portion when unlocking the ring shrinkage device;

[0026] Figure 2 A schematic view of the arching between the connecting tube and the push rod when unlocking the ring shrinkage device;

[0027] Figure 3 A schematic view of the limiting ring 121 closely adhering to the side wall of the push rod 300 in the unlocking method of the present application;

[0028] Figure 4 A schematic view of the limiting portion 132 being accommodated into the cavity 310 of the push rod 300 in the unlocking method of the present application;

[0029] Figure 5 An operation schematic view of the unlocking method of the present application;

[0030] Figure 6 An operation schematic view of the pull rod in the unlocking method of the present application;

[0031] Figure 7 A state diagram of the delivery system of the present application delivering the ring shrinkage device into the coronary sinus-cardinal vein;

[0032] Figure 8 A structural diagram of the ring shrinker in the delivery system of the present application is shown schematically;

[0033] Figure 9 An expanded state of the ring shrinker in the delivery system of the present application in the coronary sinus- great cardiac vein is shown schematically;

[0034] Figure 10 A connection relationship of the delivery system of the present application at the distal end of the ring shrinker is shown schematically;

[0035] Figure 11 A connection relationship of the delivery sheath and the loader in the delivery system of the present application is shown schematically;

[0036] Figure 12 A cross-sectional view of the loader preloaded with the ring shrinker in the delivery system of the present application is shown schematically;

[0037] Figure 13 A push rod and a push rod fixing member in the delivery system of the present application are shown schematically;

[0038] Figure 14 A cross-sectional view of the push rod 300 and the push rod fixing member 511 in the delivery system of the present application is shown schematically, wherein the inner diameter of the push rod fixing member 511 matches the outer diameter of the push rod 300;

[0039] Figure 15 A partial enlarged view of Figure 13 is shown schematically;

[0040] Figure 16 A connection relationship of the delivery system of the present application at the proximal end of the ring shrinker is shown schematically;

[0041] Figure 17 A connection relationship of the delivery system of the present application at the proximal end of the ring shrinker is shown schematically, wherein the proximal end limiting portion 132 is arrow-shaped;

[0042] Figure 18 The connection relationship of the delivery system of the present application at the proximal end of the ring shrinker is shown from another perspective;

[0043] Figure 19 A connection relationship of the connection tube and the ring shrinker in the delivery system of the present application is shown schematically;

[0044] Figure 20 A connection tube and a connection tube fixing member in the delivery system of the present application are shown schematically;

[0045] Figure 21 A partial enlarged view of Figure 20 is shown schematically;

[0046] Figure 22 The internal structure of the shell composed of the upper cover of the delivery handle and the lower cover of the delivery handle of the delivery system of the application is schematically shown;

[0047] Figure 23 The state that the superior vena cava is expanded after the distal end anchor is locked is schematically shown;

[0048] Figure 24 The first pull rod and the second pull rod of the delivery system of the application are schematically shown;

[0049] Figure 25 The connection relationship of the first pull rod, the second pull rod and the second guide of the delivery system of the application is schematically shown;

[0050] Figure 26 The connection relationship of the first pull rod, the second pull rod and the second guide of the delivery system of the application is schematically shown;

[0051] Figure 27 The operation state of the proximal end anchor pull rod and the distal end anchor pull rod in the delivery system of the application is schematically shown;

[0052] Figure 28 The cross-sectional view of the operation control assembly in the delivery system of the application is schematically shown;

[0053] Figure 29 The split type connecting tube fixing part 521 and the tail end screw 524 in the delivery system of the application are schematically shown;

[0054] Figure 30 And Figure 31 The exploded view of the operation control assembly in the delivery system of the application is schematically shown.

[0055] The reference signs are as follows:

[0056] 100 ring shrinking device; 110 anchor body; 111 proximal end anchor; 112 distal end anchor; 121 proximal end anchor limiting ring (limiting ring); 122 distal end anchor limiting ring (limiting ring); 131 distal end limiting part (limiting part); 132 proximal end limiting part (limiting part); 150 sleeve; 160 connecting rod;

[0057] 200 delivery sheath; 300 push rod; 310 cavity of the push rod; 311 cavity (for passing the connecting tube 700); 312 cavity (for passing the core wire 450); 313 cavity (for passing the proximal end pull rope 430 / distal end pull rope 440); 314 cavity (for passing the proximal end pull rope 430 / distal end pull rope 440);

[0058] 400 traction assembly; 410 first traction member (connecting wire); 420 second traction member (liner wire); 430 third traction member (proximal pull cord); 440 fourth traction member (distal pull cord); 450 first guide member (core wire); 451 third guide member (core wire guide);

[0059] 500 operation control assembly; 600 loader; 700 connecting tube;

[0060] 511 push rod fixing member; 512 limiting structure; 513 push rod controller; 521 connecting tube fixing member; 522 first traction member fixing portion (connecting wire fixing portion); 523 second traction member fixing portion (liner wire fixing portion); 524 tail end screw; 525 tail end knob;

[0061] 531 first guide member fixing portion (core wire fixing portion); 532 tail end fixing end; 533 groove structure; 534 stopper;

[0062] 541 first pull rod (proximal anchor pull rod); 542 second pull rod (distal anchor pull rod); 543 second guide member (pull rod guide); 544 second guide member (pull rod guide); 545 guide member pressing block;

[0063] 551 first position; 552 second position; 553 fixing boss; 554 fixing groove;

[0064] 560 loader control portion; 571 conveying handle upper cover; 572 conveying handle lower cover;

[0065] 800 heart; 810 great cardiac vein; 820 coronary sinus; 830 coronary circumflex artery; 840 mitral valve; 850 mitral valve annulus; 860 tricuspid valve; 870 aortic valve. DETAILED DESCRIPTION

[0066] In order to make the objectives, technical solutions, and advantages of the present application clearer, the exemplary embodiments of the present disclosure will be described in more detail below with reference to the drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Instead, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be accurately conveyed to those skilled in the art.

[0067] It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", "includes", "including" and "has" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order in which they are described, unless specifically identified as an order dependent step. It is also to be understood that additional or alternative steps can be employed.

[0068] Although the terms first, second, third, etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first", "second", and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0069] Spatially relative terms, such as "inner", "outer", "inward", "outward", "lower", "bottom", "top", "upper", and the like, can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Such spatially relative terms can encompass different orientations of the device in use or operation, depending on the particular context in which it is used. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0070] In addition, it should be noted that in the field of interventional medical devices, the end of a medical device or a delivery system for delivering the medical device that is closer to an operator is generally referred to as a "proximal end", and the end that is farther away from the operator is generally referred to as a "distal end", and the "proximal end" and the "distal end" of any component of the medical device or the delivery system are defined according to this principle. The "axial direction" generally refers to the length direction of the medical device when it is being delivered, and the "radial direction" generally refers to the direction perpendicular to the "axial direction" of the medical device, and the "axial direction" and the "radial direction" of any component of the medical device are defined according to this principle.

[0071] The unlocking method of the present application will be described below through specific embodiments.

[0072] Embodiment 1

[0073] As Figure 1 , Figure 3 and Figure 4 , the unlocking method provided by the present application is suitable for unlocking a delivery system for a shrinkable device 100, the shrinkable device 100 comprising an anchor body 110 and a limiting part 132, wherein a limiting ring 121 is arranged on one side of the anchor body 110; the delivery system comprises a push rod 300, a connecting tube 700, and a first traction member 410 and a third traction member 430; wherein the connecting tube 700 is arranged in the cavity 310 of the push rod 300, and the cavity 310 of the push rod 300 can accommodate the limiting part 132 and the limiting ring 121; the first traction member 410 is arranged in the inner cavity of the connecting tube 700 and is detachably connected with the limiting part 132; under the action of the first traction member 410, the limiting part 132 abuts against the pipe opening of the connecting tube 700, and the third traction member 430 is connected with the limiting ring 121.

[0074] The unlocking method comprises: pushing the push rod 300 in the distal direction to accommodate the limiting part 132 into the cavity 310 of the push rod 300; continuing to push the push rod 300 in the distal direction to accommodate the limiting ring 121 into the cavity 310 of the push rod 300, and the outer side of the limiting ring 121 is tightly attached to the inner wall of the cavity 310; under the elastic force of the third traction member 430 on the limiting ring 121, the limiting ring 121 is separated from the limiting part 132; thereby the delivery system completes unlocking of the proximal end of the shrinkable device 100.

[0075] In this embodiment, the third traction member 430 can be made of a metal wire with relatively large elasticity, such as a nickel-titanium wire. In this embodiment, the large cavity of the push rod 300 for accommodating the connecting tube can be designed with an inner chamfer to facilitate the entry of the limiting part 132 into the cavity 310 of the push rod 300.

[0076] The unlocking method in the embodiment can also solve the technical problem that the direction of the traction force of the third traction member 430 on the limiting ring 121 is inconsistent with the direction in which the limiting ring 121 is separated from the limiting portion 132, causing unlocking failure. Figure 1 As shown in the figure, the limiting ring cannot be separated from the limiting portion when the ring shrinkage device is unlocked, resulting in failure of the proximal end of the ring shrinkage device to be unlocked; because the ring shrinkage device is released in the coronary sinus-heart great vein after the jugular vein-superior vena cava, the angle generated when the delivery catheter enters the coronary sinus from the superior vena cava is relatively large, causing the direction of the traction force of the third traction member 430 on the limiting ring 121 to be inconsistent with the direction in which the limiting ring 121 is separated from the limiting portion 132.

[0077] Embodiment 2

[0078] In the embodiment, the difference from Embodiment 1 is that the push rod 300 and the third traction member 430 are simultaneously moved axially in the proximal direction, and the limiting ring 121 is separated from the limiting portion 132 under the elastic force of the third traction member 430 on the limiting ring 121.

[0079] For Embodiments 1 and 2, the proximal end of the ring shrinkage device is unlocked by the delivery system, and the operation method is as follows:

[0080] When the proximal end of the ring shrinkage device is unlocked, the push rod knob of the handle is counterclockwise rotated, the push rod is moved forward, and the limiting portion is received into the cavity of the push rod until the limiting portion is further contracted because the limiting portion enters the cavity of the push rod.

[0081] The proximal end of the handle is pulled, the fixed boss of the proximal end of the pull rod is rotated into the fixed groove of the pull rod guide, and the pull rod is in the first position of the pull rod guide, at which time the proximal end of the anchor limiting ring is tightly attached to the side wall of the push rod, and because the proximal end of the pull rope is elastic, the side wall of the push rod has an unlocking force of being pulled backward.

[0082] The push rod knob of the handle is clockwise rotated, the proximal end of the anchor limiting ring is retreated with the push rod, the push rod exits the limiting portion, and the proximal end of the anchor limiting ring is separated from the limiting portion in the state of the limiting portion being contracted, achieving the unlocking of the proximal end of the ring shrinkage device.

[0083] Embodiment 3

[0084] As shown in the figure, the limiting ring cannot be separated from the limiting portion when the ring shrinkage device is unlocked, resulting in failure of the proximal end of the ring shrinkage device to be unlocked; because the ring shrinkage device is released in the coronary sinus-heart great vein after the jugular vein-superior vena cava, the angle generated when the delivery catheter enters the coronary sinus from the superior vena cava is relatively large, causing the direction of the traction force of the third traction member 430 on the limiting ring 121 to be inconsistent with the direction in which the limiting ring 121 is separated from the limiting portion 132. Figure 2 , Figure 3 and Figure 4The unlocking method provided by the application is suitable for unlocking the shrinkage device 100, and the shrinkage device 100 comprises an anchor body 110 and a limiting part 132, wherein a limiting ring 121 is arranged on one side of the anchor body 110; the delivery system comprises a push rod 300, a connecting pipe 700 and a first traction member 410 and a third traction member 430; the connecting pipe 700 is arranged in the cavity 310 of the push rod 300, and the cavity 310 of the push rod 300 can accommodate the limiting part 132 and the limiting ring 121; the first traction member 410 is arranged in the inner cavity of the connecting pipe 700 and is detachably connected with the limiting part 132; under the action of the first traction member 410, the limiting part 132 abuts against the pipe opening of the connecting pipe 700, and the third traction member 430 is connected with the limiting ring 121.

[0085] The unlocking method comprises the following steps: pushing the push rod 300 to the distal end direction, so as to accommodate the limiting part 132 into the cavity 310 of the push rod 300; continuing to push the push rod 300 to the distal end direction, so as to accommodate the limiting ring 121 into the cavity 310 of the push rod 300, and the outer side of the limiting ring 121 is tightly attached to the inner wall of the cavity 310; moving the connecting pipe 700 to the distal end direction until the limiting part 132 abutting against the connecting pipe 700 is pushed to the other side of the limiting ring 121, and the limiting ring 121 is separated from the limiting part 132; thereby, the delivery system completes the unlocking of the proximal end of the shrinkage device 100.

[0086] The unlocking method in the embodiment can also solve the technical problem of arching between the connecting pipe and the push rod when the shrinkage device is unlocked, and the like. Figure 2 The arching between the connecting pipe and the push rod when the shrinkage device is unlocked is shown in the figure, and finally the proximal end of the shrinkage device fails to be unlocked; the reason is that when the first traction member 410 used for providing traction force is too small in elasticity or has no elasticity (for example, a plurality of stainless steel wires), in order to ensure that the proximal end locking ring can retreat when the push rod retreats, the proximal end pulling rope must be excessively tensioned. Since the tensioning force maintained by the proximal end pulling rope is relatively large, the flexibility of the head end of the connecting pipe is relatively strong, the push rod is a high polymer material, and the rigidity of the material is relatively weak, the connecting pipe and the push rod will arch, and sometimes the unlocking fails.

[0087] In the embodiment, the delivery system unlocks the proximal end of the shrinkage device, and the operation method is as follows:

[0088] When the proximal end of the shrinkage device is unlocked, the push rod knob of the handle is counterclockwise rotated, the push rod moves forward, until the limiting part enters the cavity of the push rod, and the limiting part is further contracted under the limitation of the cavity of the push rod;

[0089] Pull the proximal end of the handle rod, so that the proximal end of the limiting ring just sticks to the side wall of the push rod, but does not maintain tension, then the proximal end of the rod is fixed The boss is rotated into the fixed slot of the rod guide, that is, the rod is in the first position of the rod guide, which ensures that the position of the proximal end of the limiting ring is fixed.

[0090] Counter-clockwise rotation of the tail end knob, the tail end screw advances, pushing the connecting pipe forward, the reduced limiting part is ejected from the proximal end of the limiting ring, and the proximal end of the ring shrinking device is unlocked.

[0091] In this embodiment, in order to reduce the number of parts and reduce the cost, the connecting pipe fixing member and the tail end screw can be designed as an integrated type. In this embodiment, in order to facilitate assembly, the connecting pipe fixing member and the tail end screw can also be designed separately, and the quick release structure is used to connect the connecting pipe fixing member and the tail end screw together. The tail end of the connecting pipe fixing member is designed as a groove structure, and the front end of the tail end screw is designed as a boss structure, which can be quickly assembled into the groove structure.

[0092] Figure 5 The operation schematic diagram of the unlocking method of the present application is shown in Figure 5 The axial movement of the push rod 300 is controlled by the push rod controller in the conveying system, and the third traction member 430 connected with the pull rod 541 in the conveying system is controlled.

[0093] As shown in Figure 5 The pull rod 541 in the conveying system is moved to the first position 551 of the rod guide 543, and the third traction member 430 connected with the pull rod 541 provides elastic force to the limiting ring 121.

[0094] As shown in Figure 5 The pull rod 541 in the conveying system is moved to the first position 551 of the rod guide 543, and the third traction member 430 connected with the pull rod 541 provides elastic force to the limiting ring 121.

[0095] Figure 6 The operation schematic diagram of the pull rod in the unlocking method of the present application is shown in Figure 6 The fixed boss 553 is arranged in the pull rod 541, the fixed groove 554 is arranged in the rod guide 543, the fixed boss 553 can be stably fixed in the fixed groove 554, and the first position 551 is arranged in the rod guide 543, so that when the pull rod 541 is connected with the proximal end of the pull rope, the pull rod 541 pulls the proximal end of the pull rope to move axially, and can be stably fixed in the first position 551 in the axial direction.

[0096] The present application also provides a conveying system which can use the unlocking method as described above to unlock the ring shrinking device. The conveying system of the present application will be described in detail below with reference to the accompanying drawings.

[0097] In one embodiment, as shown in Figure 7 The delivery system of the present application delivers the ring constriction device to the state chart in the coronary sinus - great cardiac vein, enters the body through the jugular vein, implants the ring constriction device 100 in the coronary sinus - great cardiac vein, the ring constriction device 100 has two anchors, the distal anchor 112 is anchored at the great cardiac vein 810, the proximal anchor 111 is anchored at the coronary sinus 820, and the middle is connected by the connecting rod 160. By tightening the ring constriction device 100, inward pressure is applied to the mitral valve ring 850, the mitral valve ring 850 is constricted, and the normal geometric shape is basically restored, so that the mitral valve leaflet is tightly closed, and the mitral valve 840 regurgitation is improved.

[0098] The distal anchor 112 of the ring constriction device 100 is provided with a limiting ring 121, and the proximal anchor 111 is provided with a limiting ring 122. During the process of delivering the implant to the target position, the limiting rings 121 and 122 are not locked into the limiting portions 131 and 132, and the distal anchor 112 and the proximal anchor 111 are in a non-stable state, facilitating pushing. When the implant is delivered to the target position, the distal anchor 112 and the proximal anchor 111 are released, and the limiting ring 121 and the limiting ring 122 are controlled to be locked into the limiting portion 131 and the limiting portion 132 (the distal anchor limiting ring 122 is locked into the distal limiting portion 131, and the proximal anchor limiting ring 121 is locked into the proximal limiting portion 132), and the distal anchor 112 and the proximal anchor 111 are in a stable state, and are stably anchored in the blood vessel. When the operation is not smooth and the implant needs to be recovered, the distal anchor limiting ring 122 and the proximal anchor limiting ring 121 are controlled to be separated from the limiting portion 131 and the limiting portion 132 through the distal pull rope and the proximal pull rope, so that the distal anchor 112 and the proximal anchor 111 are returned to the non-stable state again, facilitating recovery.

[0099] In one embodiment, as shown in Figure 8 The delivery system of the present application delivers the ring constriction device to the state chart in the coronary sinus - great cardiac vein, enters the body through the jugular vein, implants the ring constriction device 100 in the coronary sinus - great cardiac vein, the ring constriction device 100 has two anchors, the distal anchor 112 is anchored at the great cardiac vein 810, the proximal anchor 111 is anchored at the coronary sinus 820, and the middle is connected by the connecting rod 160. By tightening the ring constriction device 100, inward pressure is applied to the mitral valve ring 850, the mitral valve ring 850 is constricted, and the normal geometric shape is basically restored, so that the mitral valve leaflet is tightly closed, and the mitral valve 840 regurgitation is improved.

[0100] The delivery system can also unlock the ring constriction device. The distal pull rope 440 is connected to the distal anchor limiting ring 122 along the core wire 450, and the proximal pull rope 430 is connected to the proximal anchor limiting ring 121 along the core wire 450. The core wire 450 is inserted into and clamped into the sleeve 150 in the distal direction.

[0101] In one embodiment, as shown in Figure 9As shown, the ring shrink device in the delivery system of the present application is in the inflated state in the coronary sinus-cardiac great vein, under the delivery and pushing of the push rod 300 and the delivery sheath 200, the ring shrink device is placed in the target position, and the distal end anchor 112 and the proximal end anchor 111 are in the inflated state in the coronary sinus-cardiac great vein.

[0102] In an embodiment, as shown in the figure, a connection relationship of the delivery sheath and the loader in the delivery system of the present application, the delivery sheath 200 is composed of three parts, an inner layer, a middle layer and an outer layer, the inner layer can be a 10F sheath with an inner diameter of about 2.5 mm, the inner layer uses a high polymer material with a very small friction coefficient, such as PTFE film, the middle layer can be a medical interventional grade metal woven mesh tube, such as 304V stainless steel, and the outer layer can be a high polymer material with good folding resistance, such as pebax material, the tail end of the delivery sheath 200 is connected with a Y valve, and the two outlets of the Y valve are both male luer connectors. Figure 10 As shown, a connection relationship of the delivery sheath and the loader in the delivery system of the present application, the delivery sheath 200 is composed of three parts, an inner layer, a middle layer and an outer layer, the inner layer can be a 10F sheath with an inner diameter of about 2.5 mm, the inner layer uses a high polymer material with a very small friction coefficient, such as PTFE film, the middle layer can be a medical interventional grade metal woven mesh tube, such as 304V stainless steel, and the outer layer can be a high polymer material with good folding resistance, such as pebax material, the tail end of the delivery sheath 200 is connected with a Y valve, and the two outlets of the Y valve are both male luer connectors.

[0103] In an embodiment, as shown in the figure, a connection relationship of the delivery sheath and the loader in the delivery system of the present application, the delivery sheath 200 is composed of three parts, an inner layer, a middle layer and an outer layer, the inner layer can be a 10F sheath with an inner diameter of about 2.5 mm, the inner layer uses a high polymer material with a very small friction coefficient, such as PTFE film, the middle layer can be a medical interventional grade metal woven mesh tube, such as 304V stainless steel, and the outer layer can be a high polymer material with good folding resistance, such as pebax material, the tail end of the delivery sheath 200 is connected with a Y valve, and the two outlets of the Y valve are both male luer connectors. Figure 11 As shown, a connection relationship of the delivery sheath and the loader in the delivery system of the present application, the delivery sheath 200 is composed of three parts, an inner layer, a middle layer and an outer layer, the inner layer can be a 10F sheath with an inner diameter of about 2.5 mm, the inner layer uses a high polymer material with a very small friction coefficient, such as PTFE film, the middle layer can be a medical interventional grade metal woven mesh tube, such as 304V stainless steel, and the outer layer can be a high polymer material with good folding resistance, such as pebax material, the tail end of the delivery sheath 200 is connected with a Y valve, and the two outlets of the Y valve are both male luer connectors.

[0104] The loader 600 is used to load the implant, the inner diameter of the loader 600 is the same as that of the delivery sheath 200, and the outer thread of the loader 600 is connected with the inner thread of the delivery handle loader knob; the distal end of the loader 600 is a female luer connector, which can be connected with the male luer connector of the Y valve of the delivery sheath 200.

[0105] In an embodiment, as shown in the figure, a connection relationship of the delivery sheath and the loader in the delivery system of the present application, the delivery sheath 200 is composed of three parts, an inner layer, a middle layer and an outer layer, the inner layer can be a 10F sheath with an inner diameter of about 2.5 mm, the inner layer uses a high polymer material with a very small friction coefficient, such as PTFE film, the middle layer can be a medical interventional grade metal woven mesh tube, such as 304V stainless steel, and the outer layer can be a high polymer material with good folding resistance, such as pebax material, the tail end of the delivery sheath 200 is connected with a Y valve, and the two outlets of the Y valve are both male luer connectors. Figure 12 As shown, a cross-sectional view of the loader preloading the ring shrink device in the delivery system of the present application, the ring shrink device in the contracted state is preloaded into the inner cavity of the loader, the push rod 300 and the connecting tube 700 are inserted into the proximal end of the loader, the ring shrink device in the contracted state is pushed in the distal direction, passes through the delivery sheath, and finally is pushed to the target position.

[0106] In an embodiment, as shown in Figure 13 The inner diameter of the push rod fixing member 511 matches the outer diameter of the push rod 300, and the proximal end of the push rod 300 penetrates and is fixed in the push rod fixing member 511. One end of the push rod fixing member 511 is provided with a limiting structure which slides in the matching groove of the shell but cannot rotate, so that the push rod 300 can only move in the axial direction under the action of the limiting structure of the push rod fixing member 511.

[0107] The outer diameter of the push rod fixing member 511 is provided with a thread which matches the inner thread of the push rod control knob device.

[0108] In an embodiment, as shown in Figure 14 The inner diameter of the push rod fixing member 511 matches the outer diameter of the push rod 300, and the push rod penetrates the inner hole of the push rod fixing member and can be connected together by using glue, Figure 8 The cross-sectional view is as shown in Figure 7 The cross-sectional view is as shown in

[0109] In an embodiment, as shown in Figure 15 The push rod can be a multi-cavity tube made of medical intervention high polymer material, such as polyethylene PE; wherein the middle large cavity 311 of the push rod matches the connecting tube, and the diameter of the large cavity 311 is about 0.5 mm larger than the outer diameter of the connecting tube, so as to ensure that the connecting tube can move in the push rod; there are three small cavities in the push rod, two small cavities 313 and 314 are used for passing the proximal pull rope and the distal pull rope, and the other small cavity 312 is used for passing the core wire, and the push rod is provided with multiple cavities, so as to avoid that the distal pull rope, the proximal pull rope and the core wire are wound together during the pushing process and the recovery process of the implant, Figure 9 The partial enlarged view is as shown in Figure 7 The partial enlarged view is as shown in

[0110] The large cavity 311 in the push rod through the connecting tube can be provided with an inner chamfer, so as to facilitate the proximal limiting part to enter the large cavity 311.

[0111] In an embodiment, as shown in Figure 16 The connecting wire 410 crosses from the inner side of the proximal limiting part 132, the lining wire 420 passes between the connecting wire 410 and the proximal limiting part 132, so as to ensure that the connecting wire 410 and the proximal limiting part 132 are connected together. The connecting wire 410 and the lining wire 420 pass through the middle of the connecting tube 700, the connecting wire 410 is pulled tight, the proximal limiting part 132 is tightly attached to the connecting tube 700, and the stability of the connection between the implant device and the delivery system is ensured.

[0112] The liner wire 420 passes through the connecting wire 410 and the proximal end limiting part 132, one end of the liner wire 420 is inserted into the proximal end anchor sleeve, the other end of the liner wire 420 is connected to the liner wire fixing part after passing through the push rod 300, the liner wire fixing part is rotationally fixed on the distal end screw, the liner wire fixing part controls the liner wire to retreat, and the connecting wire 410 and the proximal end limiting part 132 will be disconnected.

[0113] The front end of the connecting pipe 700 can use a processed metal pipe with good flexibility, such as a spring pipe or a snake pipe, and the rear end of the connecting pipe 700 uses a metal pipe without special processing and with good pushability, such as a stainless steel pipe or a hypotube.

[0114] In an embodiment, as shown in Figure 17 , the proximal end limiting part 132 is arrow-shaped, wherein the "arrow-shaped" of the proximal end limiting part 132 points to the connecting pipe, the proximal end limiting part 132 can abut against the connecting pipe to ensure that the ring shrinkage device is stably connected with the delivery system; when the ring shrinkage device is recovered and repositioned, the proximal end limiting part 132 can smoothly enter the push rod, and the proximal end of the ring shrinkage device can be unlocked smoothly, wherein Figure 11 is Figure 10 a partial enlarged view.

[0115] In an embodiment, as shown in Figure 18 , the connection relationship of the delivery system of the present application at the proximal end of the ring shrinkage device is shown from another perspective, the proximal end limiting part 132 can also be provided with other structures that are conducive to stable abutment with the connecting pipe or other structures that are conducive to the smooth entry of the proximal end limiting part 132 into the push rod cavity, such as

[0116] Figure 18 It is also shown that at the proximal end of the ring shrinkage device, the proximal end pull rope 430 is connected with the proximal end anchor limiting ring 121 along the core wire 450, when the ring shrinkage device is recovered or repositioned, at the proximal end of the ring shrinkage device, under the traction of the proximal end pull rope 430, the proximal end anchor limiting ring 121 can be separated from the proximal end limiting part 132, and the proximal end of the ring shrinkage device is unlocked.

[0117] In an embodiment, as shown in Figure 19 , the connection relationship of the connecting pipe of the delivery system of the present application and the ring shrinkage device is shown, the proximal end limiting part 132 is provided with a structure that is conducive to stable abutment with the connecting pipe or a structure that is conducive to the smooth entry of the proximal end limiting part 132 into the push rod cavity, such as an oval or an olive type.

[0118] In an embodiment, as shown in Figure 20As shown, the connecting tube 700 and the connecting tube fixing part 521 in the delivery system of the present application, the connecting wire 410 and the lining wire 420 are threaded in the connecting tube 700, the connecting tube 700 is fixed in the connecting tube fixing part 521, the connecting wire fixing part is further provided on the connecting tube fixing part 521, after the connecting wire is fixed, under the traction of the connecting wire, the proximal end limiting part 132 is close to the connecting tube 700, which ensures the stable connection of the implant device and the delivery system; the lining wire 420 is connected to the lining wire fixing part at the proximal end after passing through the connecting tube 700.

[0119] In an embodiment, as shown in Figure 21 , the connecting wire 410 is rotated and bent at the distal end, the lining wire 420 passes through the rotating and bending part of the connecting wire 410, Figure 15 , which is a partial enlarged view. Figure 14

[0120] In an embodiment, as shown in Figure 22 , the operation control assembly 500 in the delivery system of the present application, in the shell composed of the upper cover 571 and the lower cover 572 of the delivery handle, the loader control part 560 and the push rod controller 513 are provided, wherein the loader control part 560 is threadedly connected with the loader, the loader control part 560 controls the loader, and then controls the release of the distal end anchor of the ring shrink device in the delivery sheath, which is in the unlocked state, and the distal end anchor limiting ring is clamped into the distal end limiting part through the delivery sheath, and the superior vena cava is expanded after the distal end anchor is locked, as shown in Figure 23 .

[0121] In an embodiment, the loader control part 560 controls the release of the proximal end anchor of the ring shrink device in the delivery sheath through the control of the loader.

[0122] In an embodiment, the push rod controller 513 pushes the proximal end anchor limiting ring in the distal end direction through the control of the push rod, until the proximal end anchor limiting ring is clamped into the proximal end limiting part, and the anchoring of the proximal end anchor in the blood vessel is completed, as shown in Figure 9 .

[0123] In an embodiment, as shown in Figure 22 ​As shown, in the shell formed by the upper cover 571 and the lower cover 572 of the delivery handle, a first pull rod / near-end anchor pull rod 541, a second pull rod / far-end anchor pull rod 542 and a second guide / pull rod guide 543, a second guide / pull rod guide 544 are further arranged, wherein the first pull rod / near-end anchor pull rod 541 is connected with the near-end pull rope, the second pull rod / far-end anchor pull rod 542 is connected with the far-end pull rope, the first pull rod / near-end anchor pull rod 541 slides in the second guide / pull rod guide 543, so as to pull the near-end pull rope to move axially, and provide pulling force for unlocking the near-end anchor of the ring shrink device; the second pull rod / far-end anchor pull rod 542 slides in the second guide / pull rod guide 544, so as to pull the far-end pull rope to move axially, and similarly, provide pulling force for unlocking the far-end anchor of the ring shrink device.

[0124] In an embodiment, as shown in Figure 24 A fixing boss 553 is arranged in the first pull rod / near-end anchor pull rod 541 and the second pull rod / far-end anchor pull rod 542 respectively, and a fixing groove 554 is arranged in the first pull rod / pull rod guide 543 and the second pull rod / pull rod guide 544 respectively, wherein the fixing boss 553 can be stably fixed in the fixing groove 554, so that when the first pull rod / near-end anchor pull rod 541 is connected with the near-end pull rope, the first pull rod / near-end anchor pull rod 541 pulls the near-end pull rope to move axially, and can be stably fixed in a position axially; when the second pull rod / far-end anchor pull rod 542 is connected with the far-end pull rope, the second pull rod / far-end anchor pull rod 542 pulls the far-end pull rope to move axially, and can also be stably fixed in a position axially.

[0125] In an embodiment, as shown in Figure 25 A first position 551 and a second position 552 are arranged in the second guide / pull rod guide 543, and similarly, a first position 551 and a second position 552 are arranged in the second guide / pull rod guide 544. Figure 19 The state that the first pull rod / near-end anchor pull rod 541 is in the first position 551 and the state that the second pull rod / far-end anchor pull rod 542 is in the first position 551 are shown.

[0126] It is easy to understand that the near-end anchor pull rod 541 and the far-end anchor pull rod 542 in the delivery system of the present application are in the first position 551 of the pull rod guide 543 and the pull rod guide 544, at this time, the far-end anchor and the near-end anchor of the ring shrink device are both in the unlocking state.

[0127] In an embodiment, as shown in Figure 26As shown, the first position 551 and the second position 552 are arranged in the second guide member / rod guide member 543, and the first position 551 and the second position 552 are arranged in the second guide member / rod guide member 544 as well. Figure 20 As shown, the first position 551 and the second position 552 are arranged in the second guide member / rod guide member 543, and the first position 551 and the second position 552 are arranged in the second guide member / rod guide member 544 as well.

[0128] It is easy to understand that the proximal anchor rod 541 and the distal anchor rod 542 in the delivery system of the present application are in the second position 552 of the rod guide member 543 and the rod guide member 544, at this time, the distal anchor and the proximal anchor of the ring shrink device are both in the locked state.

[0129] In an embodiment, as shown in Figure 27 , a state of operation of the proximal anchor rod 541 and the distal anchor rod 542 in the delivery system of the present application is shown, at the proximal end of the shell formed by the upper cover of the delivery handle and the lower cover of the delivery handle, the proximal anchor rod 541 is in the first position in the second guide member, the proximal anchor limiting ring is separated from the proximal limiting part, the proximal anchor of the ring shrink device is in the unlocked state; the distal anchor rod 542 is in the second position in the second guide member, the distal anchor limiting ring is clamped into the proximal limiting part, the distal anchor of the ring shrink device is in the locked state.

[0130] In an embodiment, as shown in Figure 28 , a cross-sectional view of the operation control assembly in the delivery system of the present application is shown, at the proximal end of the shell formed by the upper cover of the delivery handle and the lower cover of the delivery handle, the first guide member / mandrel is led out from the proximal end of the cavity of the push rod, passes through the third guide member / mandrel guide member 451, and is connected with the first guide member fixing part / mandrel fixing part 531, the stopper 534 can prevent the relative movement between the first guide member fixing part / mandrel fixing part 531 and the tail end screw; the first traction member / connection wire is led out from the proximal end of the inner cavity of the connecting tube 700, and is connected with the first traction member fixing part / connection wire fixing part arranged on the connecting tube fixing member 521; the second traction member / liner wire is led out from the proximal end of the inner cavity of the connecting tube 700, and is connected with the second traction member fixing part / liner wire fixing part 523, the second traction member fixing part / liner wire fixing part 523 is provided with a stopper 534 for preventing the relative movement between the second traction member fixing part / liner wire fixing part 523 and the tail end screw.

[0131] It is easy to understand that in the operation control assembly provided by the present application, the first guide member / mandrel, the first traction member / connection wire and the second traction member / liner wire can be fixed and controlled respectively, so that the unlocking and recovery of the distal ring shrink device can be operated through the operation control assembly.

[0132] In an embodiment, as shown in Figure 29Figure 21 shows the split connecting pipe fixing member 521 and the tail end screw 524 in the delivery system of the present application; wherein the connecting pipe fixing member 521 is connected to the tail end screw 524 in a quick connection manner.

[0133] In an embodiment, as shown in Figure 30 and Figure 31 Figure 21 shows the split connecting pipe fixing member 521 and the tail end screw 524 in the delivery system of the present application; wherein the connecting pipe fixing member 521 is connected to the tail end screw 524 in a quick connection manner. Figure 24 and Figure 25 As shown in Figure 21, the second traction member fixing portion / liner wire fixing portion 523 and the first guide member fixing portion / core wire fixing portion 531 are both provided with a groove structure 533, which cooperates with a stopper 534 to prevent the second traction member fixing portion / liner wire fixing portion 523 and the first guide member fixing portion / core wire fixing portion 531 from rotating relative to the tail end screw.

[0134] The above embodiments only express several embodiments of the present application, which are described in a more specific and detailed manner, but should not be understood as a limitation to the scope of the patent. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, which are all within the scope of protection of the present application. Therefore, the scope of protection of the present application should be subject to the appended claims.

Claims

1. An unlocking method, characterized by, The unlocking method is suitable for unlocking a delivery system which is a loop shrink device (100), the loop shrink device (100) comprising an anchor body (110) and a limiting part (132) arranged at the proximal end of the anchor body, wherein a limiting ring (121) is arranged at the proximal end of the anchor body (110); the delivery system comprising a push rod (300), a connecting tube (700) and a first traction member (410) and a third traction member (430); wherein the connecting tube (700) is arranged in the cavity (310) of the push rod (300), the cavity (310) of the push rod (300) can accommodate the limiting part (132) and the limiting ring (121); the first traction member (410) is arranged in the inner cavity of the connecting tube (700) and is detachably connected with the limiting part (132); under the action of the first traction member (410), the limiting part (132) abuts against the tube opening of the connecting tube (700), and the third traction member (430) is connected with the limiting ring (121); The unlocking method comprises: Pushing the push rod (300) in the distal direction, accommodating the limiting part (132) into the cavity (310) of the push rod (300), and making the limiting ring (121) tightly adhere to the side wall of the push rod (300); By pulling the limiting ring (121), the limiting ring (121) is separated from the limiting part (132); Completing the proximal unlocking of the loop shrink device (100); At the same time, axially moving the push rod (300) and the third traction member (430) in the proximal direction, and under the elastic force of the third traction member (430) on the limiting ring (121), separating the limiting ring (121) from the limiting part (132).

2. The unlocking method according to claim 1, wherein, The limiting part (132) is accommodated into the cavity (310) through the inner chamfer of the cavity (310) of the push rod (300).

3. The unlocking method of claim 1, wherein, The axial movement of the push rod (300) is controlled by rotating the push rod controller in the delivery system.

4. The unlocking method according to claim 3, wherein, The axial movement of the third traction member (430) is controlled by pulling the pull rod (541) in the delivery system.

5. The unlocking method according to claim 4, wherein Moving the pull rod (541) in the delivery system to the first position (551) of the pull rod guide (543), so that the third traction member (430) connected with the pull rod (541) provides an elastic force to the limiting ring (121).

6. The method of claim 4, wherein, Moving the pull rod (541) in the delivery system to the first position (551) of the pull rod guide (543), under the action of the third traction member (430) connected with the pull rod (541), the relative position between the limiting ring (121) and the push rod (300) is unchanged.

7. An unlocking method characterized by, The unlocking method is suitable for unlocking a delivery system for a ring shrink device (100), the ring shrink device (100) comprising an anchor body (110) and a limiting part (132) arranged at the proximal end of the anchor body, wherein a limiting ring (121) is arranged at the proximal end of the anchor body (110); the delivery system comprising a push rod (300), a connecting tube (700) and a first traction member (410) and a third traction member (430); wherein the connecting tube (700) is arranged in the cavity (310) of the push rod (300), the cavity (310) of the push rod (300) being capable of accommodating the limiting part (132) and the limiting ring (121); the first traction member (410) is arranged in the inner cavity of the connecting tube (700) and is detachably connected with the limiting part (132); under the action of the first traction member (410), the limiting part (132) abuts against the tube opening of the connecting tube (700), and the third traction member (430) is connected with the limiting ring (121); The unlocking method comprises: Pushing the push rod (300) in the distal direction, accommodating the limiting part (132) into the cavity (310) of the push rod (300), and making the limiting ring (121) tightly abut against the side wall of the push rod (300); Disengaging the limiting ring (121) from the limiting part (132) by pushing the limiting part (132); Completing the proximal unlocking of the ring shrink device (100); Moving the connecting tube (700) in the distal direction until the limiting part (132) abutting against the connecting tube (700) is pushed to the other side of the limiting ring (121), so that the limiting ring (121) is disengaged from the limiting part (132).

8. The unlocking method according to claim 7, wherein, The limiting part (132) is accommodated into the cavity (310) through the inner chamfer of the cavity (310) of the push rod (300).

9. The method of claim 7, wherein, Under the action of the third traction member (430), the relative position of the limiting ring (121) and the push rod (300) is unchanged.

10. A delivery system characterized by, The delivery system can be unlocked according to the unlocking method of any one of claims 1-9 for a ring shrink device (100), the ring shrink device (100) comprising an anchor body (110) and a limiting part (132) arranged at the proximal end of the anchor body, wherein a limiting ring (121) is arranged at the proximal end of the anchor body (110); The conveying system comprises a push rod (300), a connecting pipe (700) and a first traction member (410) and a third traction member (430); the connecting pipe (700) is arranged in the cavity (310) of the push rod (300), and the cavity (310) of the push rod (300) can accommodate the limiting part (132) and the limiting ring (121); the first traction member (410) is arranged in the inner cavity of the connecting pipe (700) and is detachably connected with the limiting part (132); under the action of the first traction member (410), the limiting part (132) abuts against the pipe opening of the connecting pipe (700), and the third traction member (430) is connected with the limiting ring (121).

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