Recyclable filter

Abstract

The present invention provides a recyclable filter. The recyclable filter includes a filter body and a retrieval hook. The filter body includes at least one gathering portion. The retrieval hook includes a hook-shaped retrieval portion and a connecting portion integrally provided at one end of the retrieval portion. The connecting portion and the gathering portion intersect axially and are fixedly connected circumferentially. The fixed connection area between the connecting portion and the gathering portion is large, which ensures a firm connection between the connecting portion and the gathering portion, thereby ensuring the connection strength between the retrieval hook and the filter body and reducing stress concentration. The retrieval hook and the filter body can be manufactured separately and then fixedly connected, making processing more convenient.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a recyclable filter. Background Art

[0002] Pulmonary embolism (PE) is a leading cause of death in all age groups. Most PEs are caused by deep vein thrombosis (DVT) in the lower limbs or pelvis. Blood clots from DVT can migrate through the veins back to the heart and into the lungs, leading to pulmonary infarction due to the loss of blood and oxygen supply to a portion of the lung.

[0003] In cases where anticoagulation is contraindicated or ineffective, the use of a filter can prevent and reduce the occurrence of pulmonary embolism. The currently widely used recyclable filters generally include a filter body and a retrieval hook arranged at the proximal end or / and distal end of the filter body. When the filter needs to be recovered, a capture ring is usually used to cover the retrieval hook, and then the capture catheter connected to the capture ring is withdrawn to drive the capture ring and the recyclable filter into the recovery sheath. During the capture process, the connection strength between the retrieval hook and the filter body is required to be sufficiently large, and the stress concentration is required to be small enough to avoid the retrieval hook from being detached from the filter body and the retrieval hook from breaking.

[0004] The recovery hook of existing recyclable filters is generally formed from a single piece of metal wire and then spot-welded to the gathered portion of the filter body, or the recovery hook and the filter body are integrally cut and formed from a single piece of tubing. Spot welding the metal wire recovery hook to the gathered portion of the filter body is relatively easy to process. However, due to the small diameter of the metal wire, the connection strength is insufficient, which easily leads to stress concentration, resulting in a greater risk of the recovery hook becoming detached from the filter body and breaking. The recovery hook and the filter body are integrally cut and formed, which ensures the connection strength between the two bodies. However, the structure is relatively complex and inconvenient to process. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a recyclable filter in view of the defects of the prior art, which can ensure sufficient connection strength between the recovery hook and the filter body and is easy to process and manufacture.

[0006] The present invention provides a recyclable filter, which includes a filter body and a recovery hook. The filter body includes at least one gathering part. The recovery hook includes a hook-shaped recovery part and a connecting part that is arranged at one end of the recovery part and is integrated with the recovery part. The connecting part and the gathering part are interwoven with each other along the axial direction and fixedly connected around the circumference.

[0007] The recovery hook and the filter body of the recyclable filter provided by the present invention are manufactured separately and then fixedly connected, which makes processing more convenient; more importantly, the connecting part and the gathering part are interspersed with each other in the axial direction and fixedly connected around the circumference, and the fixed connection area between the connecting part and the gathering part is large, so that the connection between the connecting part and the gathering part is firm, which can ensure the connection strength between the recovery hook and the filter body and reduce stress concentration. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the implementation. Obviously, the drawings described below are some implementations of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0009] Figure 1 It is a schematic front view of a recyclable filter provided by the first embodiment of the present invention.

[0010] Figure 2 yes Figure 1 Schematic diagram of the three-dimensional structure of the recovery hook of the recyclable filter.

[0011] Figure 3 yes Figure 2 Schematic diagram of the side view structure of the recovery hook.

[0012] Figure 4 yes Figure 1 A partial cross-sectional view of the fixed connection between the recovery hook of the recyclable filter and the filter body.

[0013] Figure 5 yes Figure 2 Schematic diagram of the fixed connection between the recovery hook and another type of filter body.

[0014] Figure 6 yes Figure 5 Partial cross-sectional view of the fixed connection between the recovery hook and the filter body.

[0015] Figure 7 yes Figure 5 Schematic diagram of the usage status of the recyclable filter.

[0016] Figure 8 It is a schematic diagram of the three-dimensional structure of the recovery hook provided by the second embodiment of the present invention.

[0017] Figure 9 yes Figure 8 Schematic diagram of the side view structure of the recovery hook.

[0018] Figure 10 yes Figure 8 Schematic diagram of the fixed connection between the recovery hook and the filter body.

[0019] Figure 11 yes Figure 10 Partial cross-sectional view of the fixed connection between the recovery hook and the filter body.

[0020] Figure 12 It is a schematic structural diagram of a recovery hook provided in the third embodiment of the present invention.

[0021] Figure 13 yes Figure 12 Partial cross-sectional view of the fixed connection between the recovery hook and the filter body.

[0022] Figure 14 It is a schematic diagram of the three-dimensional structure of the recovery hook provided by the fourth embodiment of the present invention.

[0023] Figure 15 yes Figure 14 Schematic diagram of the side view structure of the recovery hook.

[0024] Figure 16 It is a schematic diagram of the three-dimensional structure of the recovery hook provided by the fifth embodiment of the present invention.

[0025] Figure 17 yes Figure 16 Schematic diagram of the side view structure of the recovery hook.

[0026] Figure 18 It is a schematic diagram of the three-dimensional structure of the recovery hook provided by the sixth embodiment of the present invention.

[0027] Figure 19 yes Figure 18 Schematic diagram of the side view structure of the recovery hook.

[0028] Figure 20 yes Figure 18 A partial cross-sectional view of the fixed connection between the recovery hook and the filter body. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In addition, the following descriptions of the embodiments refer to the accompanying drawings to illustrate specific embodiments in which the present invention may be implemented. Directional terms mentioned in the present invention, such as "upper," "lower," "front," "back," "left," "right," "inner," "outer," and "side," are only used to refer to the directions in the accompanying drawings. Therefore, the use of directional terms is for better and clearer description and understanding of the present invention, and is not intended to indicate or imply that the device or component referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, it should not be understood as limiting the present invention.

[0031] Definition of orientation: For the sake of clarity, the end close to the grasper during surgery is referred to as the "proximal end", and the end away from the grasper is referred to as the "distal end". The axial direction refers to the direction of the central axis of the device, the radial direction is the direction perpendicular to the central axis, and the circumferential direction is the circumferential direction around the central axis. This definition is only for the convenience of expression and is not to be understood as a limitation on the present invention.

[0032] See also Figures 1 to 4 The present invention provides a recyclable filter 100, which includes a recovery hook 20 and a filter body 40. The recovery hook 20 is used to pull the filter body 40. The recovery hook 20 includes a hook-shaped recovery portion 22 and a connecting portion 24 that is arranged at one end of the recovery portion 22 and is integrated with the recovery portion 22; the filter body 40 includes at least one gathering portion 42, and the connecting portion 24 and the gathering portion 42 are interlaced with each other along the axial direction and fixedly connected around the circumference.

[0033] The filter body 40 refers to the main body of the filter that has the function of filtering and intercepting thrombus. The structure of the filter body 40 can adopt the existing umbrella structure, cage structure, spindle structure, etc., wherein the proximal end or distal end of the umbrella structure is set as a gathering part, and the connecting part 24 of the recovery hook 20 is fixedly connected to the gathering part around the circumference; the proximal end and distal end of the filter body 40 with a cage structure and the filter body 40 with a spindle structure are both gathering parts, and the connecting part 24 of the recovery hook 20 is fixedly connected to at least one gathering part around the circumference.

[0034] The recovery hook 20 and the filter body 40 of the recyclable filter 100 provided by the present invention are manufactured separately and then fixedly connected, which makes processing simpler; in addition, the connecting portion 24 and the gathering portion 42 are interspersed with each other along the axial direction and fixedly connected around the circumference. Compared with the existing technology, the fixed connection area of ​​the connecting portion 24 and the gathering portion 42 is increased, and the connection between the connecting portion 24 and the gathering portion 42 is firm, which can ensure the connection strength between the recovery hook 20 and the filter body 40 and reduce stress concentration, thereby preventing the recovery hook 20 from being detached from the filter body 40 and the recovery hook from breaking.

[0035] The filter body 40 includes a filter portion 44 formed of a plurality of support rods, and the gathering portion 42 includes a sleeve for converging one end of the filter portion 44, i.e., the ends of the plurality of support rods. The connecting portion 24 can be cylindrical or columnar, and the connecting portion 24 is inserted into the sleeve, or the sleeve is inserted into the connecting portion 24, with the outer circumferential wall of the connecting portion 24 fixedly connected to the inner circumferential wall of the sleeve, or the inner circumferential wall of the connecting portion 24 is fixedly connected to the outer circumferential wall of the sleeve. In this embodiment, the connecting portion 24 is cylindrical and inserted into the sleeve, with the outer circumferential wall of the connecting portion 24 fixedly connected to the inner circumferential wall of the sleeve.

[0036] Specifically, if Figures 1 to 4 As shown, in this embodiment, the sleeve and the filter portion 44 are separate structures, and the sleeve is fixedly mounted on one end of the filter portion 44 where the filter portion 44 converges, that is, the ends of the multiple support rods to form the gathering portion 42.

[0037] In this embodiment, the filter portion 44 adopts an umbrella-like structure, including a plurality of support rods 442. The distal ends of the plurality of support rods 442 extend divergently, and the proximal ends of the plurality of support rods 442 converge at the gathering portion 42. Specifically, the proximal ends of the plurality of support rods 442 are fixedly inserted into the sleeve.

[0038] Preferably, the connecting portion 24 is fixedly connected to the sleeve by laser welding around the circumference. Figure 4 As shown, the proximal ends of several of the support rods 442 are fixedly inserted into the sleeve, and after the connecting portion 24 is axially inserted into the sleeve, the outer circumferential wall of the sleeve is continuously welded by laser around the circumference to form at least one circle of welding portions 50, and the welding portions 50 fuse the sleeve and the connecting portion 24 together; or the outer circumferential wall of the sleeve is intermittently welded by laser around the circumference to form several spaced welding portions 50, and several of the welding portions 50 form at least one circle, and each welding portion 50 fuses the sleeve and the connecting portion 24 together.

[0039] Because the laser welding area is located on the outer wall of the connecting portion 24, and the diameter of the connecting portion 24 is larger than that of the recovery portion 22, the weld area is increased, significantly improving the connection strength between the recovery hook 20 and the filter body 40 and significantly reducing stress concentration, thereby preventing the recovery hook 20 from breaking. Furthermore, the recovery hook 20 and the filter body 40 are designed as separate parts. They are manufactured separately and then fixed together by laser welding. This makes the manufacturing process much simpler than existing filters in which the recovery hook and filter body are integrally manufactured.

[0040] like Figure 2 and Figure 3As shown, the recovery portion 22 includes a hook rod 222 and an extension rod 224 connected between the hook rod 222 and the connecting portion 24. The extension rod 224 and the connecting portion 24 both extend axially, and the cross-sectional area of ​​the connecting portion 24 in the direction perpendicular to the axial direction is larger than the cross-sectional area of ​​the extension rod 224 in the direction perpendicular to the axial direction.

[0041] In this embodiment, the hook rod 222, the extension rod 224, and the connecting portion 24 are all cylindrical round rods, i.e., the cross-sections of the hook rod 222, the extension rod 224, and the connecting portion 24 are all circular, and the diameter of the connecting portion 24 is larger than the diameter of the extension rod 224. Preferably, the diameter of the connecting portion 24 is 1.5 times the diameter of the extension rod 224. The hook rod 222 and the extension rod 224 are bent from the same round rod. The extension rod 224 and the connecting portion 24 are coaxially arranged, and the recovery portion 22 and the connecting portion 24 are integrally formed.

[0042] like Figure 3 As shown, the recovery portion 22 includes at least one arcuate segment, the center of which and the central axis of the connecting portion 24 lie on the same weight line. In this embodiment, the hook rod 222 corresponds to the arcuate segment of the recovery portion 22, and the central angle of the arcuate segment ranges from 90° to 270°. That is, the central angle ϴ of the hook rod 222 ranges from 90° to 270°. Preferably, the central angle ϴ of the hook rod 222 is 120 degrees.

[0043] Furthermore, the center of the arc segment, i.e., the center of the hook rod 222, the central axis of the extension rod 224, and the central axis of the connecting portion 24, are located on the same weight line L, so that the hanging point 2220 of the hook rod 222 and the center of gravity of the filter body 40 are on the same weight line L. The hanging point 2220 refers to the contact point between the catch ring of the catcher and the hook rod 222 when the catcher is used to recover the filter. Because the hanging point 2220 is located on the weight line where the center of gravity of the recyclable filter 100 is located, the recyclable filter 100 will not swing or become unhooked during the process of the recovery hook 20 pulling the recyclable filter 100, thereby allowing the catch ring to smoothly pull the recovery hook 20 and the filter body 40 into the recovery sheath.

[0044] In other embodiments, the hook rod 222 may have a positioning groove at the hanging point 2220 for positioning the catch ring. The width of the positioning groove is equal to or slightly larger than the diameter of the catch ring. When the catch ring slides to the hanging point 2220, the catch ring is locked in the positioning groove to prevent the catch ring from falling out.

[0045] like Figure 2 and Figure 3As shown, in this embodiment, the outer shapes of the hook rod 222 and the extension rod 224 form a hook shape. The axial distance between the free end of the hook rod 222 and the proximal end of the connecting portion 24 is the axial opening dimension b of the hook shape, and the distance between the two ends of the arc-shaped segment, i.e., the hook rod 222, is the minimum opening dimension a of the hook shape. The size of the minimum opening dimension a of the hook shape determines whether the capture ring can smoothly enter the hook rod 222 and whether the capture ring can remain stable after entry. If a is too small, the capture ring will have difficulty entering the hook rod 222; if a is too large, the capture ring will easily slip out of the hook rod 222 after entry. To ensure that the capture ring can easily enter and hook the hook rod 222 while not easily slipping out of the hook rod 222, the minimum opening dimension a of the hook shape is preferably set to 0.5-1 mm. This value can be adjusted based on the diameter of the cable used to make the capture ring.

[0046] The size of the hook's axial opening dimension b determines whether the capture ring can smoothly enter the hook's minimum opening along the extension rod 224. If b is too small, the capture ring will not easily enter the hook's minimum opening along the extension rod 224; if b is too large, the longer the recovery portion 22, the greater the impact on other tissues or blood vessels in the human body. To ensure that the capture ring of the capture device can smoothly enter the hook's minimum opening along the extension rod 224 during recovery, the hook's axial opening dimension b is preferably at least twice the hook's minimum opening dimension a. At the same time, to avoid the adverse effects caused by the recovery portion 22 being too long, the hook's axial opening dimension b is set to be less than or equal to 4 times the hook's minimum opening dimension a, that is, the hook's axial opening dimension b is 2 to 4 times the hook's minimum opening dimension a. Therefore, if a is 0.5 to 1 mm, then b is 1 to 4 mm.

[0047] Furthermore, a smooth introduction section 2224 is provided between the hook rod 222 and the extension rod 224. The introduction section 2224 extends obliquely from the proximal end of the extension rod 224 toward the hook rod 222. The provision of the introduction section 2224 facilitates guiding the capture ring along the introduction section 2224 through the smallest hook-shaped opening into the hook rod 222.

[0048] Figure 5 and Figure 6The figure is a schematic diagram of the fixed connection between the recovery hook 20 in the first embodiment and another type of filter body 40a. The filter body 40a is an umbrella-shaped filter body that is cut and formed as a whole. The filter body 40a includes a plurality of support rods 442 and a gathering portion 42a. The gathering portion 42a is a sleeve, and the plurality of support rods 442 extend and diverge from the distal end surface of the sleeve. When fixing the recovery hook 20 to the filter body 40a, the connecting portion 24 is inserted into the gathering portion 42a, and a laser is used to continuously weld at least one circle around the outer peripheral wall of the gathering portion 42a to form a welding portion 50, thereby fusing the gathering portion 42a and the connecting portion 24 together. Alternatively, a laser is used to intermittently weld the outer peripheral wall of the gathering portion 42a around the circumference to form a plurality of spaced welding portions 50, and the plurality of welding portions 50 are arranged to form at least one circle, and each welding portion 50 fuses the gathering portion 42a and the connecting portion 24 together. The welding affected area is on the gathering portion 42 a and the connecting portion 24 , and has little impact on the recovery portion 22 .

[0049] like Figure 7 As shown, when retrieving the filter through the catch ring 201 of the catcher 200, the catch ring 201 is passed along the extension rod 224 and the introduction section 2224 through the smallest opening of the hook into the curved hook rod 222. When capturing and retrieving the filter, since the hanging point 2220 where the catch ring 201 contacts the recovery part 22, that is, the point of force applied for capture, is located on the same weight line L as the central axis of the extension rod 224 and the central axis of the connecting part 24, it is ensured that the center of gravity of the hanging point 2220 and the filter body 40a are on the same weight line. The filter body 40a will not be swung off the recovery hook 20 due to the deviation of the center of gravity, and the recovery jamming caused by the tilt of the filter is also avoided.

[0050] Please also refer to Figures 8-11 The structure of the recyclable filter provided in the second embodiment of the present invention is similar to that of the first embodiment, except that the structure of the recyclable filter retrieving hook 20a in the second embodiment is slightly different from that in the first embodiment, as follows:

[0051] In the second embodiment, the retrieval hook 20a also includes a hook-shaped retrieval portion 22 and a connecting portion 24 integrally formed with the retrieval portion 22 at one end. The retrieval portion 22 includes a curved hook rod 222 and an extension rod 224 connected between the curved hook rod 222 and the connecting portion 24. A guide platform 25 is provided at the junction of the extension rod 224 and the connecting portion 24. The cross-sectional area of ​​the guide platform 25, perpendicular to the axial direction, gradually increases from the end closest to the extension rod 224 toward the end closest to the connecting portion 24. The guide platform 25 effectively guides the capture ring 201 of the capture device 200 through the smallest hook-shaped opening and into the curved hook rod 222.

[0052] The guide platform can be a frustum, a prism, etc. Figure 9As shown, in this embodiment, the guide platform 25 is a frustum, comprising a distal platform 251 connected to the proximal end of the connecting portion 24 and a proximal platform 253 connected to the extension rod 224. Preferably, the frustum has a cone angle ranging from 30° to 90°, and more preferably, a cone angle of 60° for optimal guidance. When the recovery hook 20a is secured to the filter body, the distal platform 251 of the frustum abuts against the proximal end surface of the converging portion 42a, i.e., the sleeve. The diameter of the distal platform 251 is equal to or slightly smaller than the outer diameter of the converging portion 42a, while the diameter of the proximal platform 253 is equal to the diameter of the extension rod 224.

[0053] In this second embodiment, the outer shapes of the hook rod 222, the extension rod 224 and the guide platform 25 constitute the hook shape, the axial distance between the free end of the hook rod 222 and the proximal end of the connecting portion 24 is the axial opening size b of the hook shape, and the distance between the two ends of the arc segment, i.e., the hook rod 222, is the minimum opening size a of the hook shape. Similarly, in order to ensure that the capturing ring of the capture device can smoothly enter the minimum opening of the hook shape along the guide platform 25 and the extension rod 224 while avoiding the adverse effects caused by the excessive length of the recovery portion 22, the axial opening size b of the hook shape is set to 2 to 4 times the minimum opening size a of the hook shape.

[0054] like Figure 11 As shown, when the retrieval hook 20a is fixedly connected to the filter body 40a, the connecting portion 24 is inserted into the inner cavity of the gathering portion 42a, i.e., the sleeve. The distal surface 251 of the guide platform 25 abuts the proximal surface of the gathering portion 42a. Laser welding is performed around the outer circumference of the gathering portion 42a to form at least one continuous weld 50, or laser welding is performed around the outer circumference of the gathering portion 42a to form a plurality of intermittent welds 50 at intervals. This secures the outer circumference of the connecting portion 24 to the inner circumference of the gathering portion 42a, resulting in a larger weld area between the connecting portion 24 and the gathering portion 42a. Furthermore, the guide platform 25 creates a smooth transition between the retrieval portion 22 and the filter body 40a. This not only guides the capture ring into the curved hook rod 222, facilitating quick and smooth entry of the capture ring into the curved hook rod 222, but also reduces damage to the blood vessel caused by the proximal surface of the gathering portion 42a when the filter body 40a moves within the blood vessel.

[0055] Please also refer to Figure 12-13 The structure of the recyclable filter provided in the third embodiment of the present invention is similar to that of the first embodiment, except that the structure of the recyclable filter hook 20b of the third embodiment is slightly different from that of the first embodiment, as follows:

[0056] In this third embodiment, the recovery hook 20b also includes a recovery portion 22 with a hook shape and a connecting portion 24b that is arranged at one end of the recovery portion 22 and is integrated with the recovery portion 22. The recovery portion 22 includes a bent hook rod 222 and an extension rod 224 connected between the bent hook rod 222 and the connecting portion 24b. The outer diameter of the connecting portion 24b is greater than the diameter of the extension rod 224, and the outer diameter of the connecting portion 24b is greater than the outer diameter of the gathering portion 42 of the filter body, that is, the sleeve.

[0057] In this embodiment, the connecting portion 24b is a cylindrical connecting tube. The recovery portion 22 and the connecting portion 24b are integrally formed. The proximal end of the connecting portion 24b is closed and connected to the recovery portion 22. The inner diameter of the connecting portion 24b is equal to or slightly larger than the outer diameter of the gathering portion 42. The gathering portion 42, i.e., the sleeve, is inserted into the connecting portion 24b. The outer peripheral wall of the connecting portion 24b is continuously welded around the circumference to form at least one circle of welded portions 50, or the outer peripheral wall of the connecting portion 24b is intermittently welded around the circumference to form a plurality of spaced welded portions 50. This ensures that the inner peripheral wall of the connecting portion 24b is fixedly connected to the outer peripheral wall of the gathering portion 42 around the circumference, and the weld area between the connecting portion 24b and the gathering portion 42 is relatively large.

[0058] In other embodiments, the edge of the proximal end surface of the connecting portion 24b may be rounded to reduce damage to the blood vessel caused by the proximal end surface of the connecting portion 24b when the filter moves in the blood vessel.

[0059] Please also refer to Figure 14-15 The structure of the recyclable filter provided in the fourth embodiment of the present invention is similar to that of the first embodiment, except that the structure of the recyclable portion 22c of the recyclable filter recyclable hook 20c of the fourth embodiment is different from that of the first embodiment, as follows:

[0060] In the fourth embodiment, the retrieval portion 22c is a cylindrical or cylindrical structure, coaxially disposed with the connecting portion 24. The diameter of the retrieval portion 22c is greater than or equal to the diameter of the connecting portion 24 (when the connecting portion 24 is cylindrical and inserted into the gathering portion 42, the diameter of the retrieval portion 22c is greater than the diameter of the connecting portion 24; when the connecting portion is cylindrical and the gathering portion is inserted into the connecting portion, the diameter of the retrieval portion 22c is equal to the diameter of the connecting portion). The retrieval portion 22c is provided with a hook groove 26 to form the hook shape. To retrieve the filter, the capture ring enters the hook groove 26, and the capture catheter connected to the capture ring is withdrawn, driving the capture ring and the retrievable filter into the retrieval sheath.

[0061] Preferably, the diameter of the recovery portion 22 c is equal to the outer diameter of the gathering portion 42 , ie, the sleeve, that is, when the connecting portion 24 is fixedly connected to the gathering portion 42 , the outer peripheral surface of the recovery portion 22 c is flush with the outer peripheral surface of the gathering portion 42 .

[0062] In this embodiment, the hook groove 26 is opened in the middle of the recovery portion 22c, and the hook groove 26 extends obliquely toward the proximal end of the recovery portion 22c. Both opposite sides of the hook groove 26 pass through the outer peripheral surface of the recovery portion 22c.

[0063] Specifically, the hook groove 26 includes an arcuate inner surface 262 and a guide surface 264 extending from the outer circumference of the recovery portion 22c toward the arcuate inner surface 262. The arcuate inner surface 262 corresponds to the arc segment, and the guide surface 264 is tangent to the arcuate inner surface 262, thereby providing a smooth transition between the guide surface 264 and the arcuate inner surface 262. The arcuate inner surface 262 is away from the opening 260 of the hook groove 26, and the guide surface 264 is located on the side of the arcuate inner surface 262 that is closer to the connecting portion 24.

[0064] The center of the arc-shaped inner surface 262 and the center axis of the connecting portion 24 are located on the same weight line, so that when the catch ring pulls the recyclable filter, the recyclable filter will not swing or become unhooked.

[0065] When the recyclable filter is recovered, the catching ring slides into the hook groove 26 along the guide surface 264. To ensure that the guide surface 264 has good guiding properties, preferably, the angle α between the guide surface 264 and the central axis of the recovery portion 22c is 20° to 45°.

[0066] The edge of the proximal surface of the recovery portion 22c and the edge of the hook groove 26 can be rounded to reduce damage to the blood vessel caused by the proximal surface of the recovery portion 22c and the edge of the hook groove 26 when the filter moves in the blood vessel.

[0067] Please also refer to Figure 16-17 The structure of the recyclable filter provided in the fifth embodiment of the present invention is similar to that of the fourth embodiment, except that the structure of the recyclable portion 22d of the recyclable hook 20d of the fifth embodiment is different from that of the fourth embodiment, as follows:

[0068] The retrieval hook 20d also includes a connecting portion 24 and a retrieval portion 22d integrally connected to the proximal end of the connecting portion 24. The retrieval portion 22d includes a cylindrical extension rod 271 and a curved hook rod 273 disposed at the end of the extension rod 271 distal from the connecting portion 24. The cross-sectional shape of the retrieval portion 22d perpendicular to the axial direction gradually transitions from a square to a circular shape from the proximal end to the distal end. The extension rod 271 is coaxially disposed with the connecting portion 24. The diameter of the extension rod 271 is larger than that of the connecting portion 24 and is equal to the outer diameter of the gathering portion 42, i.e., the sleeve.

[0069] A first guide surface 2731 is provided in the hook rod of the recovery portion 22 d , and the first guide surface 2731 is an inwardly concave arc surface; second guide surfaces 2734 are provided on both sides of the first guide surface 2731 .

[0070] like Figure 16 As shown, the hook rod 273 includes an axial connecting section 2737 connected to the proximal end of the extension rod 271, a radial connecting section 2733 disposed proximal to the axial connecting section 2737, and a folded section 2735 disposed at the distal end of the radial connecting section 2733 and extending axially toward the extension rod 271. The extension rod 271, the axial connecting section 2737, the radial connecting section 2733, and the folded section 2735 form a hook groove 274 with an opening, forming the hook shape. A first guide surface 2731 is disposed within the opening. Second guide surfaces 2734 are disposed on opposite sides of the opening where the axial connecting section 2737 and the extension rod 271 meet. Each second guide surface 2734 extends obliquely toward the proximal end. The first and second guide surfaces 2731 and 2734 provide guidance, directing the capture ring of the capture device smoothly into the hook groove 274.

[0071] Preferably, to ensure that the first guide surface 2731 has excellent guiding performance, the angle β between the tangent of the first guide surface 2731 at the intersection with the central axis of the extension rod 271 and the central axis of the extension rod 271 is 20° to 45°.

[0072] The inner surface of the radial connecting section 2733 corresponds to the arc section, and the center of the arc section, the central axis of the extension rod 217 and the central axis of the connecting part 24 are located on the same hammer line, so that the hanging point of the recovery hook 20d and the center of gravity of the filter body are on the same hammer line, preventing the filter from swinging and unhooking during the recovery process.

[0073] In the fifth embodiment, the axial distance between the free end of the folded section 2735 and the free end of the first guide surface 2731 is the axial opening size b of the hook, and the distance between the two ends of the inner surface of the radial connecting section 2733 is the minimum opening size a of the hook. In order to ensure that the capturing ring of the capturer can smoothly enter the minimum opening of the hook along the first guide surface 2731 and avoid the adverse effects caused by the excessive length of the recovery part 22d, the axial opening size b of the hook is set to 2 to 4 times the minimum opening size a of the hook.

[0074] Please also refer to Figures 18-20 The structure of the recyclable filter provided in the sixth embodiment of the present invention is similar to that of the fourth embodiment, except that the structure of the recyclable hook 20e in the sixth embodiment is different from that in the fourth embodiment, as follows:

[0075] The retrieval hook 20e in the sixth embodiment is a cylindrical structure. The distal end of the retrieval portion 22e of the cylindrical structure serves as a connecting portion 24e. A hook groove 26e is defined in the middle of the cylindrical structure to form the hook shape. To retrieve the filter, the capture ring enters the hook groove 26e, and the capture catheter connected to the capture ring is withdrawn, pulling the capture ring and filter into the retrieval sheath.

[0076] like Figure 20 As shown, the converging portion 42 of the filter body is a sleeve for converging the ends of the filter portion 44, namely the multiple support rods 442. The inner diameter of the connecting portion 24e is equal to or slightly larger than the outer diameter of the sleeve, and the converging portion 42 is inserted into the connecting portion 24e. Laser welding is performed on the outer circumferential wall of the connecting portion 24e to form at least one continuous weld 50, or laser welding is performed on the outer circumferential wall of the connecting portion 24e to form a plurality of intermittent welds 50 at intervals. This ensures that the inner circumferential wall of the connecting portion 24e is fixedly connected to the outer circumferential wall of the converging portion 42, resulting in a larger weld area between the connecting portion 24e and the converging portion 42.

[0077] In this embodiment, the hook groove 26e extends obliquely toward the proximal end of the retrieval portion 22e, with opposite sides of the hook groove 26e penetrating the outer circumference of the retrieval portion 22e. Specifically, the hook groove 26e includes a curved inner surface 262e and a guide surface 264e extending from the outer circumference of the retrieval portion 22e toward the curved inner surface 262e. The curved inner surface 262e corresponds to the curved segment, and the guide surface 264e is tangential to the curved inner surface 262e, thereby providing a smooth transition between the guide surface 264e and the curved inner surface 262e. The curved inner surface 262e is distal to the opening 260e of the hook groove 26e, and the guide surface 264e is located on the side of the curved inner surface 262e closest to the connecting portion 24e. When retrieving the recyclable filter, the catch ring slides along the guide surface 264e into the hook groove 26e. The center of the circle corresponding to the arc-shaped inner surface 262e and the central axis of the connecting portion 24e are located on the same weight line, so that when the catch ring pulls the recyclable filter, the recyclable filter will not swing or become unhooked.

[0078] In other embodiments, the outer and inner edges of the proximal surface of the cylindrical recovery portion 22e are chamfered to reduce damage to the blood vessel caused by the proximal surface of the recovery portion 22e when the filter moves in the blood vessel.

[0079] The above is an implementation of the embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the embodiment of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A recyclable filter, comprising a filter body and a recyclable hook, wherein the recyclable hook is used to pull the filter body, the filter body comprising at least one gathering portion, characterized in that: The recovery hook includes a hook-shaped recovery portion and a connecting portion integrally provided at one end of the recovery portion, wherein the connecting portion and the gathering portion are interpenetrated with each other in the axial direction and are fixedly connected in the circumferential direction; The connecting portion is cylindrical or tubular, the filter body includes a filtering portion composed of a plurality of support rods, and the gathering portion includes a sleeve for gathering the ends of the plurality of support rods; when the connecting portion is cylindrical, the connecting portion is axially inserted into the sleeve, and the outer peripheral wall of the connecting portion is circumferentially fixedly connected to the inner peripheral wall of the sleeve; when the connecting portion is tubular, the sleeve is axially inserted into the connecting portion, and the inner peripheral wall of the connecting portion is circumferentially fixedly connected to the outer peripheral wall of the sleeve; The recovery part includes at least one arc-shaped segment; the recovery part includes a hook rod and an extension rod connected between the hook rod and the connecting part, the hook rod corresponds to the arc-shaped segment of the recovery part, the center of the arc-shaped segment, the central axis of the extension rod and the central axis of the connecting part are located on the same weight line, so that the hanging point of the hook rod and the center of gravity of the filter body are on the same weight line, and the hook rod is provided with a positioning groove for positioning the capture ring at the hanging point.

2. The recyclable filter according to claim 1, characterized in that The sleeve and the filter portion are of a separate structure or an integrated structure, and the sleeve is fixedly sleeved on one end where the plurality of support rods converge.

3. The recyclable filter according to claim 1, characterized in that The central angle corresponding to the arc segment ranges from 90° to 270°.

4. The recyclable filter according to claim 1, characterized in that A cross-sectional area of ​​the connecting portion perpendicular to the axial direction is greater than a cross-sectional area of ​​the extension rod perpendicular to the axial direction.

5. The recyclable filter according to claim 4, characterized in that A smooth introduction section is provided between the hook rod and the extension rod, and the introduction section extends obliquely from the proximal end of the extension rod toward the hook rod.

6. The recyclable filter according to claim 4, characterized in that A guide platform is provided at the connection between the extension rod and the connection portion, and a cross-sectional area of ​​the guide platform perpendicular to the axial direction gradually increases from one end close to the extension rod to one end close to the connection portion.

7. The recyclable filter according to claim 6, characterized in that The guide platform is a frustum, comprising a distal surface connected to the connecting portion and a proximal surface connected to the extension rod, and the distal surface is attached to the proximal end surface of the sleeve.

8. The recyclable filter according to claim 1, characterized in that The cross-sectional shape of the recovery portion perpendicular to the axial direction gradually transitions from a square to a circle from the proximal end to the distal end.

9. The recyclable filter according to claim 8, characterized in that A first guide surface is provided in the hook shape, and the first guide surface is an inwardly concave arc surface; and second guide surfaces are respectively provided on both sides of the first guide surface.

10. The recyclable filter according to claim 1, characterized in that The axial opening size of the hook is 2 to 4 times the minimum opening size of the hook.

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