Filter system

Abstract

The present application relates to a filter system, comprising a filter, a distal end of the filter is gathered to a distal end piece, a proximal end of the filter is gathered to a connecting piece, interiors of the connecting piece and the distal end piece are penetrated along an axial direction, a delivery device, the delivery device comprises a sheath and a delivery piece capable of moving along an interior of the sheath, the delivery piece comprises a deformation zone and a connecting zone arranged in sequence from a distal end to a proximal end, wherein the connecting zone is detachably connected to the connecting piece, the deformation zone comprises at least two support rods, distal ends of the support rods can pass through the connecting piece and then pass through the distal end piece. By arranging a deformation zone, the filter can leave the sheath in advance, which can facilitate an operator to monitor whether a to-be-released position is accurate, in addition, a stable supporting force is formed on a distal end side of the filter in a releasing stage, and a possibility of displacement and deviation of the filter is reduced.

Description

Technical Field

[0001] This invention relates to the field of interventional medical device technology, and more particularly to a filter system. Background Technology

[0002] Interventional therapy is a minimally invasive treatment technique that uses catheters and other instruments under the guidance of medical imaging equipment to treat diseases. The delivery of the medical device is a crucial step in interventional therapy. In existing technologies, for filters, the filter itself is generally used as a imaging marker to indicate its position. To accurately determine if it has reached the correct position, it usually needs to be removed from the sheath before imaging. However, the filter itself is a high-strength structure formed by cutting; if its position is inaccurate after removal from the sheath, it is difficult to retract the sheath and re-release it. Furthermore, unnecessary retrieval operations can significantly affect its lifespan and introduce unpredictable risks. Summary of the Invention

[0003] Therefore, it is necessary to provide an improved filter system to address the problems existing in the current filter system, as follows:

[0004] A filter system is provided, including

[0005] A filter, wherein the distal end of the filter converges to a distal member, and the proximal end of the filter converges to a connecting member, wherein the interior of both the connecting member and the distal member extends axially through the filter.

[0006] A conveying device includes a sheath and a conveying member that can move along the inside of the sheath. The conveying member includes a deformable region and a connecting region arranged sequentially from the distal end to the proximal end. The connecting region is detachably connected to the connecting member. The deformable region includes at least two support rods. The distal end of the support rod can pass through the connecting member and then through the distal member and through the connecting member.

[0007] In one embodiment, the deformable region includes a first support rod and a second support rod, which extend from the distal end of the connecting region. In their natural state, the first support rod and the second support rod extend at an angle to the distal end, respectively.

[0008] In one embodiment, the first support rod and the second support rod extend outward at an angle to the far end, then bend and extend towards the near end, thereby forming a backbend structure.

[0009] In one embodiment, the deformable region and the connecting region are rotatably connected.

[0010] In one embodiment, the sum of the diameters of the first support rod and the second support rod is less than the smallest of the inner diameters of the distal end member and the connector.

[0011] In one embodiment, the end of the first support rod and / or the end of the second support rod is provided with a ball head.

[0012] In one embodiment, the sum of the diameters of the ball heads of the first support rod and the second support rod is less than the smallest of the inner diameters of the distal end member and the connector.

[0013] In one embodiment, the actual length of the first support rod is greater than the actual length of the second support rod.

[0014] In one embodiment, the diameter of the ball end of the first support rod and the diameter of the ball end of the second support rod are both smaller than the inner diameter of the distal end member.

[0015] In one embodiment, the deformable region and the connecting region are detachably connected.

[0016] Compared with the prior art, the present invention provides a filter system including a filter, the distal end of which converges to a distal member, and the proximal end of which converges to a connecting member. Both the connecting member and the distal member are axially penetrating the interior. A conveying device includes a sheath and a conveying component that can move along the interior of the sheath. The conveying component includes a deformation zone and a connecting zone arranged sequentially from the distal to the proximal end. The connecting zone is detachably connected to the connecting member. The deformation zone includes at least two support rods, the distal ends of which can pass through the connecting member, the distal member, and then through the connecting member. By providing a deformation zone that exits the sheath before the filter, the operator can easily monitor the accuracy of the release position. Furthermore, during the release phase, a stable supporting force is formed on the distal side of the filter, reducing the possibility of filter displacement or offset. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the filter system in the natural state of the filter in Embodiment 1 of the present invention;

[0018] Figure 2 This is a schematic diagram of the conveying device of the filter system in its natural state in Embodiment 1 of the present invention;

[0019] Figure 3 This is a schematic diagram of the filter and conveying device of the filter system in Embodiment 1 of the present invention in the released state;

[0020] Figure 4 This is a schematic diagram of the filter and conveying device of the filter system in the conveying state in Embodiment 1 of the present invention;

[0021] Figure 5 This is a schematic cross-sectional view of the conveying device of the filter system in its natural state in Embodiment 2 of the present invention;

[0022] Figure 6 This is a cross-sectional schematic diagram of the conveying device of the filter system in the natural state in Embodiment 3 of the present invention;

[0023] Figure 7 This is a cross-sectional schematic diagram of the conveying device of the filter system in Embodiment 3 of the present invention under the first state. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] It should be noted that in the field of interventional medical devices, the end of a medical device implanted in the human or animal body that is closer to the operator is generally called the "proximal end," and the end that is farther from the operator is called the "distal end." Based on this principle, the "proximal end" and "distal end" of any component of a medical device are defined. "Axial direction" generally refers to the length direction of the medical device during delivery, and "radial direction" generally refers to the direction of the medical device perpendicular to its "axial direction." Based on this principle, the "axial direction" and "radial direction" of any component of a medical device are defined. The "connection" mentioned in the embodiments includes both direct connection between two components and indirect connection via other components.

[0026] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0027] Example 1

[0028] Refer to the instruction manual appendix Figure 1-4 , Figure 1 This is a schematic diagram of the filter 100 of the filter system in Embodiment 1 of the present invention in its natural state. Figure 2 This is a schematic diagram of the conveying device 200 of the filter system in its natural state in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the filter 100 and conveying device 200 of the filter system in Embodiment 1 of the present invention in the released state; Figure 4This is a schematic diagram of the filter 100 and conveying device 200 of the filter system in the conveying state in Embodiment 1 of the present invention. This embodiment provides a filter system including a filter 100 and a corresponding conveying device 200. For the filter 100, the filter 100 includes a main body 110, a proximal end 120 and a distal end 130. The proximal end 120 and the distal end 130 are respectively disposed on the proximal side and the distal side of the main body 110. The main body 110 includes a plurality of axially extending and circumferentially distributed support members. The proximal end 120 extends from the main body 110 and its proximal end gradually converges to a connector 121. The distal end 130 extends from the main body 110 and its distal end gradually converges to a distal end member 131. In this embodiment, the connector 121 is preferably a steel sleeve with internal threads, and the connector 121 is axially penetrating inside. The distal end member 131 is preferably a steel sleeve, and the distal end member 131 is axially penetrating inside.

[0029] For the filter 100, the prior art generally uses a steel cable for delivery. The distal end of the steel cable is detachably fixed to the proximal end 120 of the filter 100. After the filter is removed from the sheath by the steel cable, the filter expands under its own tendency to restore its shape and then forms an implant. Then the steel cable is manipulated to detach it from the filter, and then the steel cable is withdrawn.

[0030] The conveying device 200 provided in this embodiment includes a conveying component 210 and a sheath 220. The conveying component 210 is an axially extending long straight cylinder. The conveying component 210 can move along the inside of the sheath 220 to complete the conveying. The conveying component 210 includes a deformation area 211, a connecting area 212, and a main body area 213 arranged sequentially from the distal end to the proximal end. The connecting area 212 includes an axially extending external thread structure. The thread of the connecting area 212 is provided to correspond to the internal thread of the connector 121 of the proximal end 120 of the filter 100. Therefore, the connecting area 212 and the connector 121 are detachably connected.

[0031] In this embodiment, the connecting area 212 can be rotated to completely pass through the position of the connector 121.

[0032] The main body 213 includes an externally covered spring tube structure. The spring tube can increase the strength of the conveyor 210 without affecting its bending performance, and can assist in transmitting the rotational torque from the proximal end, avoiding excessive lag for the operator when operating the conveyor 200 due to the excessive length of the main body 213.

[0033] In this embodiment, the connector 121 and the distal part 131 of the filter 100 are internally axially penetrating, and the conveying part 210 connected to the connector 121 can pass through the connector 121. Specifically, the deformation zone 211 can pass through the connector 121 and the distal part 131.

[0034] In this embodiment, the deformation zone 211 includes at least two support rods, referred to as the first support rod 2111 and the second support rod 2112. The first support rod 2111 and the second support rod 2112 extend from the far end of the connecting zone 212, and then the first support rod 2111 and the second support rod 2112 extend obliquely to the far end, and after bending, extend to the proximal end, thereby forming a back-bending structure. In this embodiment, the first support rod 2111 and the second support rod 2112 are preferably made of shape memory metals such as nickel-titanium.

[0035] In another embodiment, in order to enhance the developing effect of the first support rod 2111 and the second support rod 2112, additional developing material can be added to the ends of the first support rod 2111 and the second support rod 2112.

[0036] In this embodiment, the ends of the first support rod 2111 and the second support rod 2112 are provided with ball heads.

[0037] During transport, please refer to the instruction manual again. Figure 4 , attached Figure 4 The simplified state of the filter 100 and the conveying device 200 in the conveying state is shown. The filter 100 is in the sheath of the conveying device 200 and is compressed and elongated. The connecting part 121 of the filter 100 is connected to the connecting area 212 of the conveying member 210 of the conveying device 200. The conveying member 210 passes through the connecting part 121 and the distal member 130 of the filter 100. Specifically, the connecting area 212 of the conveying member 210 is threadedly connected to the connecting part 121 of the filter 100. The deformable area 211 of the conveying member 210 passes through the distal member 131 of the filter 100. The first support rod 2111 and the second support rod 2112 are also compressed and elongated. The ball ends of the first support rod 2111 and the second support rod 2112 are located on the distal side of the distal member 131.

[0038] During the release phase, please refer to the instruction manual again. Figure 3 During release, the ball heads at the ends of the first support rod 2111 and the second support rod 2112 first leave the sheath 220 of the delivery device 200. The first support rod 2111 and the second support rod 2112 begin to deform and return to their original shape without being subjected to external force. The first support rod 2111 and the second support rod 2112 gradually expand and press against the inner wall of the blood vessel, thereby achieving the following effects:

[0039] (1) When the first support rod 2111 and the second support rod 2112 are released, their ends reach the inner wall of the blood vessel. It can be monitored whether they have reached the predetermined position. If the position is incorrect, they can be pulled back directly. The first support rod 2111 and the second support rod 2112 are retracted into the sheath 220 and then released again. During this process, the filter 100 is still inside the sheath 220 and there is no deformation after release. That is, there is no need to perform the action of retraction and adjustment, which is conducive to maintaining the integrity of the filter 100's lifespan.

[0040] (2) When the predetermined position is reached, the first support rod 2111 and the second support rod 2112 are released. The first support rod 2111 and the second support rod 2112 also abut against the inner wall of the blood vessel and play a certain limiting role. Thus, during the release process, the filter 100 is limited from the proximal end by the delivery member 210, and is also limited from the distal end by the first support rod 2111 and the second support rod 2112, thereby ensuring the stability of the delivery state.

[0041] (3) When the filter 100 is released, the distal end 131 is supported by the first support rod 2111 and the second support rod 2112 against the inner wall of the blood vessel, and the proximal end connector 121 is also fixed with the delivery member 210. Thus, both the proximal and distal ends of the filter 100 are supported, which makes the filter 100 well centered and has a low possibility of displacement when released.

[0042] (4) In addition to the above effects, it should also be noted that since the filter 100 is shaped like a spindle, when the proximal end 120 of the filter 100 is detached from the sheath 220, the proximal end 120 moves toward the distal end and expands at the same time. There is pressure and corresponding reaction force on the edge of the sheath 220. If the delivery component 210 fails to provide sufficient tension (i.e., the operator does not tighten it), the expansion of the proximal end 120 is unrestricted. Part of the resultant force of the reaction force given to the proximal end 120 by the sheath 220 is directed toward the distal end, which will cause the proximal end 120 to push the filter 100 out a short distance toward the distal end. On the one hand, this may cause impact and damage to the blood vessel wall, and on the other hand, it may also cause the filter 100 to shift. In this embodiment, after the filter 100 reaches the predetermined position, it is resisted by the first support rod 2111 and the second support rod 2112 when it moves toward the far end. The resistance is applied to the edge of the far end member 131 of the filter 100 through the first support rod 2111 and the second support rod 2112, so that the force of the resistance is in the center position and will not cause the filter to deviate.

[0043] After release, the delivery member 210 is detached from the filter 100, and the first support rod 2111 and the second support rod 2112 pass through the distal member 131 of the filter 100 and are pulled back into the sheath 220.

[0044] In another embodiment, the first support rod 2111 and the second support rod 2112 extend from the far end of the connecting area 212. Then, the first support rod 2111 and the second support rod 2112 extend outward at an angle and no longer bend, that is, they directly expand radially. Compared with this embodiment, the resistance generated after expansion is greater and the stability is better. However, the thrust required for the pusher 210 to continue pushing and releasing towards the far end will also increase.

[0045] Since the conveyor 210 needs to rotate when it is detached from the filter 100, in this embodiment, preferably, the deformation zone 211 and the connecting zone 212 are rotatably connected for the conveyor 210. Specifically, the proximal end of the deformation zone 211 is fixed to a bearing, and the bearing is fixed to the distal end of the connecting zone 212. Thus, the rotation of the connecting zone 212 does not affect the deformation zone 211.

[0046] In essence, since the filter 100 has already been implanted when it is released, the rotation of the deformation zone 211 will not affect the filter 100. Since the deformation zone 211 itself does not pierce the blood vessel wall, its rotation itself will not cause damage. The bearing design is only to minimize other possible effects.

[0047] In this embodiment, the total length of the first support rod 2111 and the second support rod 2112 is greater than the total length of the filter 100 in its natural state (that is, the distance from the proximal end to the distal end of the filter 100 in its natural state). This results in the proximal end of the first support rod 2111 and the second support rod 2112 entering the sheath 220 and being restricted by the sheath 220 before the distal end of the first support rod 2111 and the second support rod 2112 have passed through the distal end member 131 when the conveying member 210 is withdrawn.

[0048] In another embodiment, the ends of the first support rod 2111 and the second support rod 2112 are not provided with ball heads, and the ends of the first support rod 2111 and the second support rod 2112 are bent back in their extension direction to avoid the ends directly contacting the blood vessel wall. In this embodiment, since the ends of the first support rod 2111 and the second support rod 2112 are not provided with ball heads, they will not interfere with or squeeze each other in the sheath 220.

[0049] In this embodiment, in order to ensure that the deformation zone 211 of the conveying component 210 works normally, the sum of the diameters of the first support rod 2111 and the second support rod 2112 is less than the smaller inner diameter of the inner diameter of the distal end component 131 of the filter 100 and the inner diameter of the connector 121, thereby ensuring that the first support rod 2111 and the second support rod 2112 can freely pass through the distal end component 131.

[0050] In this embodiment, the ends of the first support rod 2111 and the second support rod 2112 are provided with ball heads. Therefore, the sum of the diameter of the ball head at the end of the first support rod 2111 and the diameter of the ball head at the end of the second support rod 2112 is less than the smallest inner diameter among the inner diameter of the distal end member 131 of the filter 100 and the inner diameter of the connector 121, thereby ensuring that the first support rod 2111 and the second support rod 2112 can freely pass through the distal end member 131.

[0051] In another embodiment, to avoid the ball ends of the first support rod 2111 and the second support rod 2112 squeezing each other during transport, the actual length of the first support rod 2111 is greater than the actual length of the second support rod 2112, so that the ball ends of the first support rod 2111 and the second support rod 2112 are at different axial positions. At the same time, for the recycling process, only one ball end passes through the distal end 131 at any given time. Therefore, in this embodiment, the diameter of the ball end of the first support rod 2111 and the diameter of the ball end of the second support rod 2112 are both smaller than the inner diameter of the distal end 131 of the filter 100.

[0052] In another embodiment, the inner diameter of the distal member 131 is greater than or equal to the inner diameter of the connector 121. Therefore, to ensure the normal operation of the deformation zone 211 of the conveyor 210, the sum of the diameters of the first support rod 2111 and the second support rod 2112 is less than the diameter of the connector 121 of the filter 100, thereby ensuring that the first support rod 2111 and the second support rod 2112 can freely pass through the distal member 131. If the ends of the first support rod 2111 and the second support rod 2112 are provided with ball heads, then the first support rod... The sum of the diameter of the end ball of the first support rod 2111 and the diameter of the end ball of the second support rod 2112 is less than the inner diameter of the connector 121 of the filter 100. If the actual length of the first support rod 2111 is greater than the actual length of the second support rod 2112, only one ball can pass through the distal part 131 at any given time. Therefore, in this embodiment, the diameter of the end ball of the first support rod 2111 and the diameter of the end ball of the second support rod 2112 are both less than the inner diameter of the connector 121 of the filter 100.

[0053] In this embodiment, when pre-assembling the filter 100 and the conveyor 210, the first support rod 2111 and the second support rod 2112 are first passed through the connector 121 and the distal part 131 of the filter 100, and then the connection area 212 of the conveyor 210 is tightened with the connector 121 of the filter 100.

[0054] In another embodiment, the deformation area 211 and the connecting area 212 are detachably connected, so that they can be assembled separately during pre-assembly. The specific connection method can be a snap-fit ​​or a threaded connection. However, in the threaded structure, the direction of the thread must be opposite to the direction of the thread in the connecting area 212. This is because the deformation area 211 is separated from the connecting area 212 only for the convenience of assembly, and after pre-assembly, the deformation area 211 does not need to be separated from the connecting area 212.

[0055] Example 2

[0056] The improvement of Example 2 compared to Example 1 focuses on the conveying device itself, specifically, referring to... Figure 5 , Figure 5 This is a schematic cross-sectional view of the conveying device of the filter system in its natural state according to Embodiment 2 of the present invention. In this embodiment, the conveying component 210 includes an inner tube 230 and an outer tube 240 sleeved outside the inner tube 230. A deformation zone 211 is located at the distal end of the inner tube 230, and a connecting zone 212 and a main body zone 213 are sequentially located at the distal end of the outer tube 240. The inner tube 230 and the outer tube 240 are relatively independent and can move freely. In this embodiment, the first support rod 2111 and the second support rod 2112 of the deformation zone 211 extend from the distal end of the inner tube 230.

[0057] The functions of the deformation zone 211, the connecting zone 212, and the main body zone 213 are the same as in Embodiment 1. The inner tube 230 can drive the first support rod 2111 and the second support rod 2112 of the deformation zone 211 to move freely. Thus, the rotation of the outer tube 240 does not affect the inner tube 230. In addition, during preloading, the inner tube 230 can be used to pass through the distal end member 131 and the connecting member 121 of the filter 100 from the distal end to the proximal end. Then, the outer tube 240 can be screwed onto the filter 100 from the proximal end to the distal end.

[0058] In this embodiment, the total length of the first support rod 2111 and the second support rod 2112 is greater than the total length of the filter 100 in its natural state (that is, the distance from the proximal end to the distal end of the filter 100 in its natural state). This ensures that when the conveying member 210 is withdrawn, the proximal end of the first support rod 2111 and the second support rod 2112 has entered the inner tube 230 and is restricted by the inner tube 230 before the distal end of the first support rod 2111 and the second support rod 2112 has passed through the distal end member 131. Since the inner diameter of the inner tube 230 is smaller than that of the sheath 200, this setting is more effective in this embodiment.

[0059] In another embodiment, the maximum diameter of the first support rod 2111 and the maximum diameter of the second support rod 2112 are both smaller than the inner diameter of the outer tube 240. That is, the maximum diameter of the deformation zone 211 is smaller than the diameter of the outer tube 240. Thus, when the deformation zone 211 does not need to function, the deformation zone 211 can be completely retracted into the outer tube 240 under the action of the inner tube 230, and the outer tube 240 can be used for operation. However, in the corresponding release process, the distal end of the inner tube 230 needs to be extended axially through the distal end member 131 first. Otherwise, the first support rod 2111 and the second support rod 2112 cannot pass through the distal end member 131 to function.

[0060] In this embodiment, it is also important to note that the relative position of the inner tube 230 and the outer tube 240 determines the amount of extension of the deformation zone 211 relative to the distal member 131, that is, the amount of unfolding deformation of the deformation zone 211. Therefore, if the relative position of the inner tube 230 and the outer tube 240 is shortened and fixed, the portion of the deformation zone 211 extending beyond the distal member 131 will also limit the filter 100. At this time, the filter 100 is essentially clamped between the distal side of the deformation zone 211 and the connecting area 212, and the clamping force is adjustable. In this case, there is no need to wait for the deformation zone 211 to contact the blood vessel wall to limit the filter 100, thereby minimizing the impact on the human body. Therefore, a limiting pin can be added. When the limiting pin is inserted, it penetrates the inner tube 230 and the outer tube 240, and the relative axial position of the inner tube 230 and the outer tube 240 is locked.

[0061] In this embodiment, the inner tube 230 and the outer tube 240 can also be connected by threads. When passing through the threaded area, the two can only rotate relative to each other and cannot slide, thereby maintaining the sealing of the inner tube 230 and the outer tube 240. In order to prevent the inner tube 230 from rotating and causing the deformation zone 211 to rotate, the proximal side of the deformation zone 211 is fixed on the bearing, and the bearing is fixed to the distal end of the inner tube 230.

[0062] Example 3

[0063] The improvement of Example 3 compared to Example 1 or Example 2 focuses on the conveying device, specifically, referring to... Figure 6-7 , Figure 6 This is a cross-sectional schematic diagram of the conveying device of the filter system in the natural state in Embodiment 3 of the present invention; Figure 7 This is a cross-sectional schematic diagram of the conveying device of the filter system in the first state according to Embodiment 3 of the present invention.

[0064] The conveying component 210 includes a restraining component 250, which is slidably disposed outside the deformation zone 211. The position of the restraining component is controlled by a rod passing through the inside of the conveying component 210. When the restraining component 250 slides axially, the distance between the first support rod 2111 and the second support rod 2112 can be controlled within the inner diameter of the restraining component 250. The position of the restraining component 250 can also adjust the shape of the first support rod 2111 and the second support rod 2112 after release, so that they can obtain greater or less support force. In addition, when preloading, moving the restraining component 250 to the far end of the deformation zone 211 can make the far ends of the first support rod 2111 and the second support rod 2112 generally form a straight line, which is conducive to loading. Furthermore, when transporting within the sheath, the restraining component remaining at the far end of the deformation zone 211 can also significantly reduce the resistance of the conveying.

[0065] In this embodiment, the outer diameter of the restraint member 250 is smaller than the inner diameter of the connector 121, thereby ensuring that the restraint member 250 can be freely removed.

[0066] It should be noted that the technical features of the above embodiments can be combined arbitrarily and can also be applied to various types of filters and filters with similar structures as described above. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; however, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification.

[0067] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A filter system, characterized in that, include A filter, wherein the distal end of the filter converges to a distal member, and the proximal end of the filter converges to a connecting member, wherein the interior of both the connecting member and the distal member extends axially through the filter. A conveying device, comprising a sheath and a conveying member capable of moving along the interior of the sheath, the conveying member comprising a deformable region and a connecting region arranged sequentially from distal to proximal end, wherein the connecting region is detachably connected to the connecting member, the deformable region comprising at least two support rods, the distal ends of the at least two support rods being able to pass through the connecting member and then through the distal member; The at least two support rods include a first support rod and a second support rod, which extend from the distal end of the connecting area. In their natural state, the first support rod and the second support rod extend distally to abut against the inner wall of the blood vessel. It also includes a restraint member, which is slidably disposed outside the deformation zone. The position of the restraint member can be used to adjust the shape of the first support rod and the second support rod after release, so that they can obtain greater or less support force.

2. The filter system according to claim 1, characterized in that, The first support rod and the second support rod extend outward at an angle to the far end, then bend and extend towards the near end, thus forming a back-bend structure.

3. The filter system according to claim 1, characterized in that, The deformation zone and the connection zone are rotatably connected.

4. The filter system according to claim 1, characterized in that, The sum of the diameters of the first support rod and the second support rod is less than the smallest inner diameter among the inner diameters of the distal end piece and the connecting piece.

5. The filter system according to claim 1, characterized in that, The end of the first support rod and / or the end of the second support rod is provided with a ball head.

6. The filter system according to claim 5, characterized in that, The sum of the diameters of the ball heads of the first support rod and the second support rod is less than the smallest of the inner diameters of the distal end member and the connecting member.

7. The filter system according to claim 5, characterized in that, The actual length of the first support rod is greater than the actual length of the second support rod.

8. The filter system according to claim 7, characterized in that, The diameter of the ball head at the end of the first support rod and the diameter of the ball head at the end of the second support rod are both smaller than the inner diameter of the distal end piece.

9. The filter system according to claim 1, characterized in that, The deformation zone and the connection zone are detachably connected.

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