CN109771088B

CN109771088B - Filter device

Info

Publication number: CN109771088B
Application number: CN201811573377.0A
Authority: CN
Inventors: 贾小乐; 张贵
Original assignee: Lifetech Scientific Shenzhen Co Ltd
Current assignee: Lifetech Scientific Shenzhen Co Ltd
Priority date: 2018-12-21
Filing date: 2018-12-21
Publication date: 2021-12-03
Anticipated expiration: 2038-12-21
Also published as: CN109771088A

Abstract

The invention discloses a filter, which comprises a connecting rod assembly, and a first filter screen and a second filter screen which are arranged at intervals along the axial direction of the connecting rod assembly, wherein the first filter screen and the second filter screen are fixed on the connecting rod assembly and respectively extend in a radiation mode towards the direction far away from the connecting rod assembly, the first filter screen comprises a plurality of support rods used for supporting the inner wall of a blood vessel, the second filter screen comprises a first support rod, and the first support rod and the support rods are connected in a separable mode. The invention has the beneficial effects that: this application is connected with separable mode through making first branch and bracing piece, not only can improve the stability of filter when using, has still prolonged the recovery time window of filter, has effectively satisfied clinical demand.

Description

Filter device

Technical Field

The invention relates to the technical field of interventional medical instruments, in particular to a filter.

Background

This section provides background information related to the present disclosure only and is not necessarily prior art.

Pulmonary Embolism (PE) is a common disease, has high fatality rate, and can be caused by various emboli falling off in the systemic circulation. The vena cava filter (hereinafter referred to as filter) is clinically proved to be a safe and effective means for preventing pulmonary embolism, and the filter is placed in the inferior vena cava to filter thrombus falling off from the inferior vena cava, so that the fallen thrombus is prevented from reaching the lung along the blood flow, and the incidence rate of the pulmonary embolism is reduced.

At present, filters on the market are mainly permanent filters and temporary filters. Wherein, once the permanent filter is used, the patient must take medicine for life, and the filter is implanted into the body for a long time, and the filter has the danger of deformation, inclination, displacement, fracture, even penetrating the blood vessel, etc. Therefore, it is clinically recommended to use a temporary filter, which is inserted during the acute phase of deep venous thrombosis and removed when the risk of thrombus detachment is reduced after the acute phase.

The temporary filter is mainly divided into a single umbrella open filter and a closed frame type filter, wherein the single umbrella open filter comprises a plurality of support rods, one ends of the support rods are open ends, the other ends of the support rods are gathered together to form a closed end, and the support rods at the open ends are in contact with blood vessels to play a role in fixing the filter. Because the supporting rod at the open end is like a nail embedded in the vessel wall, even if the supporting rod is attached and wrapped by endothelial cells, the supporting rod can be easily pulled out by external force at any time according to needs, so that the recovery period of the single umbrella open filter is longer. However, since one end of the single umbrella open type filter has an open structure, the supporting rod at the open end of the filter has weak supporting force on the blood vessel, and the filter is easy to incline and shift under the influence of blood flow and external force, and even causes complications such as perforation of the blood vessel wall. The closed frame type filter comprises a plurality of support rods, the two ends of the support rods are respectively gathered together to form a closed end, the support rods are in contact with blood vessels to play a role in fixing the filter, the stability of the closed frame type filter is good, the filter is not prone to inclination and displacement, however, because the two ends of the filter are closed, if the support rods of the filter are covered and wrapped by endothelial cells, the implanted filter is difficult to take out, and therefore, in order to avoid the support rods from being attached by the endothelial cells, the recovery time window of the closed frame type filter is short.

Therefore, how to prolong the recovery time window of the filter and ensure the stability of the filter in vivo is a difficult problem to be solved urgently.

Disclosure of Invention

The object of the present invention is to solve at least one of the problems of the prior art mentioned above, and the object is achieved by the following technical solutions:

the invention provides a filter, which comprises a connecting rod assembly, and a first filter screen and a second filter screen which are arranged at intervals along the axial direction of the connecting rod assembly, wherein the first filter screen and the second filter screen are fixed on the connecting rod assembly and respectively extend in a radiation mode in the direction far away from the connecting rod assembly, the first filter screen comprises a plurality of supporting rods, the second filter screen comprises a first supporting rod, and the first supporting rod and the supporting rods are connected in a separable mode.

In the filter of the present invention, the support rod is connected to the first support rod by a degradable connecting member.

In the colander of the present invention, the connecting rod assembly includes a first connecting rod and a second connecting rod slidably connected, the first filter net is fixed on the first connecting rod, and the second filter net is fixed on the second connecting rod.

In the filter of the present invention, a locking mechanism is disposed between the first link and the second link, and when the locking mechanism is unlocked, the first link and the second link can slide relatively.

In the strainer of the present invention, the support rods are fixed to the connecting rod assembly and extend radially away from the connecting rod assembly.

In the strainer of the present invention, the first strainer further includes a plurality of connecting rods, one end of each of the connecting rods is fixed to the connecting rod assembly, and the other end of each of the connecting rods is connected to the support rod.

In the filter of the present invention, the number of the first support rods is plural, the plural first support rods are distributed around the circumference of the connecting rod assembly, and the first support rods are fixed to the connecting rod assembly and extend radially away from the connecting rod assembly.

In the filter of the present invention, the second filter screen further includes a second support rod, one end of the second support rod is fixed to the connecting rod assembly, and the other end of the second support rod extends radially away from the connecting rod assembly and is used for supporting the inner wall of the blood vessel.

In the filter of the invention, one end of the support rod is bent and extended towards one side of the longitudinal central axis of the filter to form a lower bent section.

In the filter, the distance between two ends of the lower folding section is 5-20 mm, and the included angle between the connecting line of the two ends of the lower folding section and the longitudinal central axis of the filter is 20-60 degrees.

In summary, the filter embodying the present invention has the following beneficial effects: according to the blood vessel filter, the first supporting rod is connected with the supporting rod in a separable mode, when the filter is used, the supporting rod is connected with the first supporting rod, and the supporting rod can be tightly attached to the inner wall of a blood vessel under the auxiliary support of the first supporting rod, so that the overall stability of the filter is improved, and the filter is prevented from inclining and shifting under the influence of factors such as blood flow and the like; when the filter is required to be recovered, the connection between the support rod and the first support rod is released, after the support rod is separated from the first support rod, the support rod and the first support rod are both like nails embedded into the inner wall of a blood vessel, the support rod and the first support rod can be easily pulled out, the recovery time window of the filter is prolonged, and the clinical requirement is effectively met.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

FIG. 1 is a schematic view of a strainer according to a first embodiment of the present invention in a compressed state;

FIG. 2 is a schematic view of the filter of FIG. 1 returned to a predetermined configuration;

FIG. 3 is a schematic view of the linkage assembly of the colander of FIG. 2 including first and second links slidably connected;

FIG. 4 is a schematic view of the support rods of the strainer of FIG. 3 shown separated from the first support rods;

FIG. 5 is a schematic view of a first detachable connection of the support rod to the first branch of the strainer of FIG. 3;

FIG. 6 is a schematic view of a second detachable connection of the support rod to the first leg of the strainer of FIG. 3;

FIG. 7 is a schematic view of a first configuration of a connecting rod of a first screen of the strainer of FIG. 3;

FIG. 8 is a schematic view of a second configuration of a connecting rod of the first screen of the strainer of FIG. 3;

FIG. 9 is a schematic view of a second screen of the colander of FIG. 3;

FIG. 10 is a schematic view of a second screen of the strainer of FIG. 3 including second struts;

FIG. 11 is a schematic view of a first configuration of a locking mechanism of the colander of FIG. 3;

FIG. 12 is a schematic view of a second configuration of the locking mechanism of the colander of FIG. 3;

FIG. 13 is a schematic view of a support rod of a colander according to a second embodiment of the present invention when connected to a first support rod;

FIG. 14 is a schematic view of a strainer according to a third embodiment of the present invention;

FIG. 15 is a schematic view of a first configuration of a locking mechanism of the colander of FIG. 14;

figure 16 is a schematic view of a second configuration of the locking mechanism of the colander of figure 14.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather should be construed as broadly as the present invention is capable of modification in various respects, all without departing from the spirit and scope of the present invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the field of interventional medicine, it is generally defined that an implant (e.g., a luminal stent) is proximal at the end proximal to the heart and distal at the end distal to the heart after release.

The first embodiment:

referring to fig. 1 and 2, a first embodiment of the present invention provides a filter 100 that may be made of a superelastic shape memory alloy material, such as nitinol, such that the filter 100 may be contained within a delivery sheath in a compressed state and may automatically return to a predetermined configuration after release from the delivery sheath. Fig. 1 is a schematic view of filter 100 in a compressed state, and fig. 2 is a schematic view of filter 100 returning to a predetermined configuration in which filter 100 is in a closed frame configuration.

Referring to fig. 2, the strainer 100 includes a connecting rod assembly 3, and two first and

second strainers

1 and 2 arranged at intervals along an axial direction of the connecting rod assembly 3, wherein the first and

second strainers

1 and 2 are fixed on the connecting rod assembly 3 and respectively extend in a radial direction away from the connecting rod assembly 3. The first sieve 1 comprises a plurality of struts 11 for supporting on the inner wall of a blood vessel, and the second sieve 2 comprises first struts 21, the first struts 21 being detachably connected to the struts 11. The support rod 11 is connected to the first support rod 21 when the filter 100 is in the predetermined configuration.

When the filter 100 is in use, the filter 100 is in a predetermined shape, the support rod 11 is connected with the first support rod 21, and the support rod 11 can be tightly attached to the inner wall of the blood vessel under the auxiliary support of the first support rod 21, so that the stability of the whole filter is improved, and the filter 100 is prevented from inclining and shifting under the influence of factors such as blood flow. When the filter 100 needs to be recovered, the connection between the support rod 11 and the first support rod 21 is released, and after the support rod 11 is separated from the first support rod 21, the support rod 11 and the first support rod 21 can be easily pulled out like a nail embedded in the inner wall of a blood vessel. Therefore, the first support rod 21 and the support rod 11 are detachably connected, so that the filter 100 has good stability in use, is convenient to recover, prolongs the recovery time window of the filter, and effectively meets clinical requirements.

Further, the strainer 100 further includes a recovery hook 4, and the recovery hook 4 may be selectively provided at an end of the link assembly 3 adjacent to the first screen 1 or an end adjacent to the second screen 2. In the present embodiment, the recovery hook 4 is provided at an end of the link assembly 3 near the first screen 1. Filter 100 further includes a fixation anchor 5 disposed on support rod 11, which fixation anchor 5 penetrates the inner wall of the blood vessel when filter 100 is implanted, which acts to fix filter 100.

Referring to fig. 3 and 4, the connecting rod assembly 3 includes a first connecting rod 31 and a second connecting rod 32 slidably connected, the first filter 1 is connected to the first connecting rod 31, and the second filter 2 is connected to the second connecting rod 32. When the strainer 100 is recovered, the first link 31 and the second link 32 are relatively moved by an external force, so that the first screen 1 and the second screen 2 are relatively moved until the connection between the support bar 11 of the first screen 1 and the first support bar 21 of the second screen 2 is released.

Referring to fig. 5, the supporting rod 11 is provided with a sliding slot 110 extending to an end of the supporting member 11, and the end of the first supporting rod 21 is provided with a sliding member 210, and the sliding member 210 is slidably connected in the sliding slot 110. When the colander is in the predetermined configuration, the slide 210 is positioned within the chute 110. When the filter is recovered, the slider 210 moves in the chute 110 until the slider 210 is separated from the end of the support rod 11, releasing the connection between the support rod 11 and the first support rod 21.

In the present embodiment, the connection between the support lever 11 and the first lever 21 is released by relatively moving the first link 31 and the second link 32, but the present invention is not limited to a specific manner of releasing the connection between the support lever 11 and the first lever 21. For example, in the embodiment shown in fig. 6, the support rod 11 and the first strut 21 are connected by the degradable connecting element 6, and the degradation period of the degradable connecting element 6 is about the same as the time window of the filter 100 implanted in the body, that is, when the filter 100 reaches the time of extraction, the degradable connecting element 6 is completely degraded or the mechanical property of the material thereof is lost, so that the restriction between the support rod 11 and the first strut 21 is released, and the first link 31 and the second link 32 can not move relatively.

Referring to fig. 7, the first filter screen 1 further includes a plurality of connecting rods 12 located between the supporting rods 11 and the first connecting rods 31, and the plurality of connecting rods 12 are spaced around the circumference of the first connecting rods 31. One end of the connecting rod 12 is fixed on the first connecting rod 31, the other end of the connecting rod 12 extends towards the direction far away from the first connecting rod 31 and the direction radiation near the second filter screen 2, the supporting rod 11 is connected at the other end of the connecting rod 12, and the connecting rod 12 can assist the supporting rod 11 to make the supporting rod 11 tightly fit with the inner wall of the blood vessel. In this embodiment, the number of the support rods 11 is the same as that of the connecting rods 12, each connecting rod 12 is correspondingly connected to one support rod 11, the plurality of support rods 11 are circumferentially spaced around the first connecting rod 31, the support rods 11 and the connecting rods 12 are straight rods, and the support rods 11 are substantially parallel to the axial direction of the first connecting rod 31.

It should be understood that the present embodiment is not limited to the specific structure of the first filter screen 1, and in other embodiments, the first filter screen 1 may only include a plurality of support rods 11, where one end of each support rod 11 is fixed on the first connecting rod 31, and the other end of each support rod 11 extends radially away from the first connecting rod 31 and is used for abutting against the inner wall of the blood vessel. Alternatively, in other embodiments, the connecting rod 12 is a supporting rod of other shapes, for example, in the embodiment shown in fig. 8, the connecting rod 12 is a Y-shaped rod including a main branch section 12a and two branch sections 12b branched from one end of the main branch section 12a, the other end of the main branch section 12a is connected to the first connecting rod 31, and each branch section 12b is connected to one supporting rod 11. Alternatively, in other embodiments, the first filter 1 further includes other rod-like or net-like structures between the support rods 11 and the first connecting rods 31, as long as the other rod-like or net-like structures do not contact with the inner wall of the blood vessel, so as to ensure that only the support rods 11 of the first filter 1 contact with the inner wall of the blood vessel, and at this time, the first filter 1 can be easily pulled out like nails embedded in the inner wall of the blood vessel.

It should also be understood that the present embodiment is not limited to the specific structure of the support rod 11 or the connecting rod 12, and in other embodiments, the support rod 11 or the connecting rod 12 may also be a bent rod or a combined rod of a bent rod and a straight rod. For example, when the support rod 11 is a curved rod, the support rod 11 extends toward the side away from the second filter screen 2 and gradually turns reversely to be curled, so that the support rod 11 is supported on the inner wall of the blood vessel. It will also be appreciated that the present embodiment does not limit the extending direction of the first screen 1, and the first screen 1 may extend towards a side away from or close to the second screen 2.

Referring to fig. 9, the second filter screen 2 includes a plurality of first supporting rods 21 distributed around the circumference of the second connecting rod 32, one end of each first supporting rod 21 is connected to the second connecting rod 32, and the other end of each first supporting rod 21 extends radially away from the second connecting rod 32 and is detachably connected to the supporting rod 11. In the present embodiment, the first strut 21 extends toward the side away from the first screen 1, but the present embodiment does not limit the structure of the first strut 21, and in other embodiments, the first strut 21 may also extend toward the side close to the first screen 1, or the first strut 21 may be turned upside down after extending toward the side close to the first screen 1.

It should be understood that the plurality of first supporting rods 21 and the plurality of supporting rods 11 may be all detachably connected, or a part of the supporting rods 11 and the corresponding first supporting rods 21 may be detachably connected. When a plurality of first branch 21 and a plurality of bracing piece 11 are all connected with separable mode, the quantity of first branch 21 is the same with the quantity of bracing piece 11, and each first branch 21 forms the support to each bracing piece 11 respectively for each bracing piece 11 supports respectively and leans on the vascular wall, thereby effectively improves the whole radial strength of filter, makes the stability of filter 100 obtain further improvement, avoids appearing complications such as filter slope, aversion, improves the safety that the patient used.

It is understood that the present embodiment does not limit the specific structure of the second screen 2, for example, in the embodiment shown in fig. 10, the second screen 2 further includes a plurality of second struts 22 distributed around the circumference of the second link 32, one end of the second struts 22 is fixed on the second link 32, and the other end of the second struts 22 extends radially away from the second link 32 and is used for supporting the inner wall of the blood vessel. Due to the complicated structure in the blood vessel, the inner wall of the blood vessel is supported by the second support rod 22 and the support rod 11, so that the filter 100 can be supported and fixed in different planes of the blood vessel, the stability and the like of the filter 100 are further enhanced, and the use safety is ensured. In order to prevent the second struts 22 from piercing the inner wall of the blood vessel, the portions of the second struts 22 that contact the inner wall of the blood vessel are arc-shaped segments that contact the inner wall of the blood vessel at points. Alternatively, in other embodiments, the second screen 2 may also include other rod-like or net-like structures between the first struts 21 and the second links 32, as long as the other rod-like or net-like structures do not contact the inner wall of the blood vessel.

In order to increase the safety factor of clinical use and avoid the random relative movement of the first link 31 and the second link 32 under the impact of blood flow or the radial pressure of the inner wall of the blood vessel after the filter 100 is implanted into the blood vessel, a locking mechanism 33 is disposed between the first link 31 and the second link 32. When the locking mechanism 33 is in the locked state, the first link 31 and the second link 32 are not movable relative to each other; when the locking mechanism 33 is unlocked, the first link 31 and the second link 32 can slide relatively.

In the embodiment shown in fig. 11, a sliding groove 311 is provided in the first link 31 and penetrates in the axial direction, and one end of the second link 32 is slidably coupled in the sliding groove 311.

The locking mechanism 33 includes a plurality of limiting grooves 331 axially disposed on an inner wall of the sliding groove 311, and a limiting member 332 disposed on an end or an outer wall of the second link 32, wherein the limiting member 332 can slide from one limiting groove 331 to another limiting groove 331 under the action of an external force. In particular, the limiting member 332 is made of a flexible material, which is elastically deformable by a force. The side wall surface of the stopper groove 331 away from the recovery hook 4 is an inclined surface, and the side wall surface of the stopper groove 331 close to the recovery hook 4 is a substantially vertical surface. The side wall surface of the stopper 332 that is away from the recovery hook 4 is also an inclined surface, the inclined surface of the stopper 332 is substantially the same as the inclined surface of the stopper groove 331 in inclination angle, and the side wall surface of the stopper 332 that is close to the recovery hook 4 is also substantially a vertical surface. Because the side wall surfaces of the limiting groove 331 and the limiting member 332 far away from the recovery hook 4 are inclined surfaces, the two inclined surfaces can be matched to play a driving role, and the limiting member 332 can conveniently slide into the other limiting groove 331 from one limiting groove 331. In addition, since the side wall surfaces of the limit groove 331 and the limit member 332 close to the recovery hook 4 are both vertical surfaces, the two vertical surfaces can be engaged to play a role in stopping, so that the limit member 332 cannot move toward one side of the recovery hook 4. Therefore, the locking mechanism 33 of the present embodiment can ensure that the first link 31 and the second link 32 can move relatively only under the action of a large external force, and the first link 31 can move only in one direction, thereby ensuring the stability of the filter 100 in the blood vessel. In order to prevent the limiting member 332 from sliding off the end of the sliding slot 311 and separating the first link 31 from the second link 32, the limiting slot 331 is located at a position other than the end of the sliding slot 311 in the embodiment.

In the present embodiment, the specific structure of the locking mechanism 33 is not limited, and the first link 31 and the second link 32 may be prevented from moving relative to each other. For example, in the embodiment shown in fig. 12, a slide groove 311 is provided in the first link 31 so as to penetrate in the axial direction, and one end of the second link 32 is slidably connected to the slide groove 311.

The locking mechanism 33 includes a fixing groove 333 provided on an outer wall of the first link 31 in communication with the sliding groove 311, and a fixing member 334 projected on an outer wall of the second link 32, the fixing member 334 being slidably coupled in the fixing groove 333. Specifically, the fixing groove 333 includes a fixing section 3331, a connecting section 3332, and a sliding section 3333, which are sequentially connected. The sliding section 3333 extends in the axial direction of the first link 31, and one end of the connecting section 3332 is connected to one end of the sliding section 3333 near the recovery hook 4 and extends in the circumferential direction of the first link 31. The fixing section 3331 is connected to the other end of the connecting section 3332 and extends in the axial direction of the first connecting rod 31 toward the side away from the recovery hook 4. When the colander is in the predetermined configuration, the mount 334 is located within the fixed section 3331; when the strainer is recovered, the fixing member 334 is moved from the fixing section 3331 into the connecting section 3332 by an external force, and then the second link 32 is rotated to move the fixing member 334 from the connecting section 3332 into the sliding section 3333, thereby relatively moving the first link 31 and the second link 32.

In order to increase the stability of the fixing member 334 sliding in the fixing groove 333, the widths of the fixing section 3331, the connecting section 3332, and the sliding section 3333 are the same as the outer diameter of the fixing member 334. In order to reduce the time of application of external force, it is convenient for an operator to move the fixing member 334 from the fixing section 3331 to the sliding section 3333 as soon as possible, and the length of the fixing section 3331 is smaller than that of the sliding section 3333. In order to prevent the first link 31 from being separated from the second link 32, the fixing groove 333 is located at a position other than the end of the first link 31 in the present embodiment.

Referring to fig. 13, a second embodiment of the present invention provides a colander which is substantially the same as the first embodiment except for the detachable connection between the support rods 11 and the first support rods 21.

Referring to fig. 13, the end of the first support bar 21 is provided with a connection ring 211, and the support bar 11 is movably fitted in the connection ring 211. The support rod 11 is inserted through the connection ring 211 when the strainer is in a predetermined configuration. When the filter is collected, the support rod 11 and the connection ring 211 are relatively moved until the support rod 11 is separated from the connection ring 211, thereby releasing the connection between the support rod 11 and the first rod 21.

One end of the support rod 11 far away from the recovery hook 4 is bent and extended towards one side of the longitudinal central axis of the filter to form a lower bent section 111. The lower bent section 111 may facilitate the separation of the support rod 11 from the connection ring 211 during the withdrawal, and the lower bent section 111 may prevent the end of the support rod 11 from stabbing the inner wall of the blood vessel.

If the distance between the two ends of the lower bent section 111 is too large, the support rod 11 is not easily separated from the connection ring 211 when the filter is recovered; if the distance between the two ends of the lower bent section 111 is too small, the support rod 11 is easily separated from the connection ring 211 during the use of the filter, which may affect the supporting function of the first support rod 21 on the support rod 11. Moreover, if the included angle between the connecting line of the two ends of the lower folding section 111 and the longitudinal central axis of the filter is too large, the bending part of the lower folding section 111 is easy to stab the vascular wall; if the angle between the connecting line of the two ends of the lower folding section 111 and the longitudinal central axis of the filter 100 is smaller, the effect of disposing the lower folding section 111 is not significant. Therefore, in this embodiment, the distance between the two ends of the lower folded section 111 is 5mm to 20mm, and the angle between the line connecting the two ends of the lower folded section 111 and the longitudinal central axis of the filter is 20 ° to 60 °. This application is through the distance at 111 both ends of adjustment turn down section simultaneously, and the line at 111 both ends of turn down and the contained angle of the vertical center pin of filter, can be convenient for bracing piece 11 break away from in the go-between 211 when retrieving, and avoid the tip of bracing piece 11 to stab the intravascular wall.

Furthermore, the end of the support rod 11 far from the recovery hook 4 is provided with a spherical part 112 with a smooth outer contour to avoid the end of the support rod 11 from stabbing the inner wall of the blood vessel.

When the support rod 11 is inserted into the connection ring 211, that is, when the first strut 21 is connected to the support rod 11, the end of the first strut 21 remote from the second link 32 can be inserted into the inner wall of the blood vessel to improve the stability of the filter 100 as a whole. Specifically, when the filter 100 is in the predetermined configuration, the end of the first strut 21 remote from the second link 32 passes over the support bar 11, and the difference in height between the end of the first strut 21 remote from the second link 32 and the support bar 11 in the radial direction of the filter is not greater than 5mm to avoid the first strut 21 from puncturing the vessel wall.

Referring to fig. 14, a third embodiment of the present invention provides a strainer, which is substantially the same as the strainer of the first embodiment, the strainer 100 includes a connecting rod assembly 3, and a first strainer 1 and a second strainer 2 respectively fixed to the connecting rod assembly 3, the first strainer 1 includes a plurality of support rods 11 for supporting on the inner wall of a blood vessel, the second strainer 2 includes a first support rod 21, and the first support rod 21 is detachably connected to the support rods 11. The support rod 11 is connected to the first support rod 21 when the filter 100 is in the predetermined configuration.

The third embodiment differs from the first embodiment in that the link assembly 3 includes a first link 31 and a second link 32 which are detachably connected, the first screen 1 is fixed to the first link 31 and extends radially away from the first link 31, and the second screen 2 is fixed to the second link 32 and extends radially away from the second link 32.

Because first connecting rod 31 and second connecting rod 32 separable connection, then can be with first filter screen 1 and the split of second filter screen 2 become two independent filter screen units, can retrieve first filter screen 1 and second filter screen 2 respectively in the time quantum of difference. For example, when the filter 100 is implanted for a period of time, the first sieve 1 intercepts a large amount of thrombus, and the second sieve 2 does not intercept a large amount of thrombus, the first sieve 1 loaded with thrombus may be taken out first, and the second sieve 2 may be taken out after the second sieve 2 intercepts a large amount of thrombus.

Referring to fig. 14, the first connecting rod 31 and the second connecting rod 32 are respectively connected with a recovery hook 4, the recovery hook 4 on the first connecting rod 31 is located at an end of the first connecting rod 31 far away from the second filter screen 2, and the recovery hook 4 on the second connecting rod 32 is located at an end of the second connecting rod 32 near the first filter screen 1.

In the embodiment shown in fig. 15, the first link 31 is provided with a sliding groove 311 extending therethrough in the axial direction, and one end of the second link 32 is slidably coupled in the sliding groove 311. The locking mechanism 33 includes a plurality of limiting grooves 331 axially disposed on an inner wall of the sliding groove 311, and a limiting member 332 disposed on an end portion or an outer wall of the second link 32, the plurality of limiting grooves 331 extending to an end portion of the sliding groove 311. Under the action of external force, the limiting member 332 can slide from one limiting groove 331 to the other limiting groove 331 until the second link 32 is separated from the first link 31. In particular, the limiting member 332 is made of a flexible material, which is elastically deformable by a force. The side wall surface of the stopper groove 331 away from the recovery hook 4 is an inclined surface, and the side wall surface of the stopper groove 331 close to the recovery hook 4 is a substantially vertical surface. The side wall surface of the stopper 332 that is away from the recovery hook 4 is also an inclined surface, the inclined surface of the stopper 332 is substantially the same as the inclined surface of the stopper groove 331 in inclination angle, and the side wall surface of the stopper 332 that is close to the recovery hook 4 is also substantially a vertical surface. Because the side wall surfaces of the limiting groove 331 and the limiting member 332 far away from the recovery hook 4 are inclined surfaces, the two inclined surfaces can be matched to play a driving role, and the limiting member 332 can conveniently slide into the other limiting groove 331 from one limiting groove 331. In addition, since the side wall surfaces of the limit groove 331 and the limit member 332 close to the recovery hook 4 are both vertical surfaces, the two vertical surfaces can be engaged to play a role in stopping, so that the limit member 332 cannot move toward one side of the recovery hook 4. Therefore, the locking mechanism 33 of the present embodiment can ensure that the first link 31 and the second link 32 can move relatively only under the action of a large external force, and the first link 31 can move only in one direction, thereby ensuring the stability of the filter 100 in the blood vessel.

In the present embodiment, the specific structure of the locking mechanism 33 is not limited, and the first link 31 and the second link 32 may be prevented from moving relative to each other. For example, in the embodiment shown in fig. 16, a slide groove 311 is provided in the first link 31 so as to penetrate in the axial direction, and one end of the second link 32 is slidably connected to the slide groove 311. The locking mechanism 33 includes a fixing groove 333 provided on an outer wall of the first link 31 in communication with the sliding groove 311, and a fixing member 334 protrudingly provided on an outer wall of the second link 32, the fixing member 334 being slidably coupled in the fixing groove 333, the fixing groove 333 extending to an end of the first link 31 so that the fixing member 334 can be disengaged from the fixing groove 333. Specifically, the fixing groove 333 includes a fixing section 3331, a connecting section 3332, and a sliding section 3333, which are sequentially connected. The sliding section 3333 extends to an end of the first link 31 in the axial direction, and one end of the connection section 3332 is connected to an end of the sliding section 3333 near the recovery hook 4 and extends in the circumferential direction of the first link 31. The fixing section 3331 is connected to the other end of the connecting section 3332 and extends in the axial direction of the first connecting rod 31 toward the side away from the recovery hook 4. When the colander is in the predetermined configuration, the fixture 334 is positioned within the fixed section 3331. When the strainer is recovered, the fixing member 334 is moved from the fixing section 3331 into the connecting section 3332 by an external force, and then the fixing member 334 is moved from the connecting section 3332 into the sliding section 3333 by rotating the second link 32.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The utility model provides a filter, includes link assembly, and two edges first filter screen and the second filter screen that link assembly's axial interval was arranged, first filter screen is fixed with the second filter screen link assembly is last and respectively towards keeping away from link assembly's direction radiation extends, its characterized in that, first filter screen includes a plurality of bracing pieces, the second filter screen includes a plurality of first branches, first branch with the bracing piece is connected with separable mode.

2. The strainer of claim 1 wherein the support rods are connected to the first support rods by degradable connectors.

3. The colander of claim 1, wherein the linkage assembly comprises a first linkage and a second linkage slidably connected, the first screen being secured to the first linkage and the second screen being secured to the second linkage.

4. The colander of claim 3, wherein a locking mechanism is disposed between the first and second links, the first and second links being slidable relative to each other when the locking mechanism is unlocked.

5. The colander of claim 1, wherein the support rods are secured to the linkage assembly and extend radially away from the linkage assembly.

6. The colander of claim 1, further comprising a plurality of connecting rods, one end of the connecting rods being secured to the connecting rod assembly and the other end of the connecting rods being connected to the support rod.

7. The colander of claim 1, wherein the first struts are a plurality of and are distributed around the circumference of the connecting rod assembly, the first struts being secured to the connecting rod assembly and each extending radially away from the connecting rod assembly.

8. The strainer of claim 1 further comprising a second strut, one end of the second strut being secured to the connecting rod assembly and the other end of the second strut extending radially away from the connecting rod assembly and adapted to support an inner wall of a blood vessel.

9. The filter of claim 1, wherein one end of the support rod is bent toward one side of the longitudinal central axis of the filter to form a lower bent section.

10. The filter of claim 9, wherein the distance between the two ends of the lower folded section is 5mm to 20mm, and the included angle between the connecting line of the two ends of the lower folded section and the longitudinal central axis of the filter is 20 ° to 60 °.