Pre-bending sheathing canal and conveyor

Abstract

The invention provides a pre-bent sheathing canal and a conveyor. The pre-bent sheathing canal comprises an outer-layer tube with an axial length and a reinforcing tube, wherein the reinforcing tube is embedded in the outer-layer tube; the reinforcing tube comprises a plurality of supporting pieces and axial connecting pieces which are arranged in the axial direction, and the supporting pieces and the axial connecting pieces are connected to form an arc-shaped tube with a bending angle, so that the reinforcing tube has the bending angle in the natural state, and force for keeping the bending state is provided for the bending position of the pre-bending sheath tube. Therefore, the sheathing canal is prevented from returning in the transportation and long-term storage process, and excessive operation of medical staff on the sheathing canal before an operation is effectively avoided; meanwhile, the reinforcing tube enables the pre-bent sheathing canal to have higher bending resistance, and the situation that the sheathing canal seriously deforms when large bending occurs, and passing and releasing of the covered stent are affected can be effectively avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly to a pre-bent sheath tube and a delivery device. Background Art

[0002] The pathophysiology of aortic dissection is the rupture of the aortic intima, and the blood flow rushes into the middle layer of the aorta, resulting in the splitting of the middle layer of the aorta to form true and false lumens. In conventional medical techniques, for Stanford type A aortic dissection patients with lesions in the entire aorta (including the ascending aorta, aortic arch, descending aorta, and abdominal aorta), median sternotomy is generally used for treatment. An artificial blood vessel is used to replace the aortic arch of the ascending aorta, and a section of artificial blood vessel is inserted into the true lumen of the descending aorta to prepare for secondary surgery or secondary interventional treatment (covered stent implantation). The interventional stent delivery devices on the market are generally straight sheaths, which often do not match the actual blood vessel morphology well, affecting the pushing of the device to the lesion site. The human blood vessel morphology has a certain bending angle. Especially in the iliac artery / abdominal aorta / aortic arch, etc., the surgical difficulty is often increased due to the large bending angle of the blood vessel, posing a great challenge to the device. Many surgeons will bend the delivery sheath tube by hand in advance to conform to the blood vessel morphology. This method better increases the passing ability, but at the same time, it cannot ensure that the bending angle is in the correct position, and the hand contact with the delivery sheath tube is likely to cause the peeling of the surface hydrophilic coating, resulting in a decrease in the pushing performance and an increased risk of thrombus formation. Summary of the Invention

[0003] Based on this, it is necessary to provide a pre-bent sheath tube and a delivery device, which have a pre-bent structure and do not require manual bending of the sheath tube during the operation. While avoiding the peeling of the surface hydrophilic coating caused by hand contact with the delivery sheath tube, it can always maintain a good original pre-bent angle during long-term storage and transportation, and avoid the straightening of the sheath tube.

[0004] A pre-bent sheath tube includes an outer tube and a reinforcing tube having an axial length, and the reinforcing tube is embedded in the outer tube; the reinforcing tube includes a support unit arranged along the length direction, the support unit includes two support members and at least one axial connecting member, and the axial connecting member connects two adjacent support members; the axial connecting member has elasticity; the axial connecting member makes the reinforcing tube have a bending angle at least in the natural state.

[0005] In one embodiment, the axial connecting member includes a first connecting end at the proximal end and a second connecting end at the distal end, and there is an included angle between the connecting end face of the first connecting end and the connecting end face of the second connecting end.

[0006] In one embodiment, the support member includes a proximal connecting surface and a distal connecting surface, and there is an included angle between the proximal connecting surface and the distal connecting surface.

[0007] In one embodiment, the support unit includes a first support member and a second support member, and there is an included angle between the proximal connection surface and / or the distal connection surface of the first support member and the distal connection surface and / or the proximal connection surface of the second support member.

[0008] In one embodiment, the support member can expand or contract radially, and the support member has a circular radial cross-section in both the natural state and the stressed state.

[0009] In one embodiment, the support member includes a plurality of support sheets arranged circumferentially and a circumferential connecting member. Adjacent support sheets are connected by the circumferential connecting member, and the axial connecting member is connected to the support sheet. The circumferential connecting member has elasticity.

[0010] In one embodiment, in the natural state, the reinforcing tube includes a large bend side and a small bend side, and there are two side positions between the large bend side and the small bend side; at least two support sheets are provided, which are respectively arranged at the side positions and partially extend to the large bend side and the small bend side.

[0011] In one embodiment, the support member includes four support sheets, and the four support sheets are respectively arranged on the large bend side, the small bend side and the two side positions.

[0012] In one embodiment, the reinforcing tube is arranged between the distal end and the proximal end of the pre-bent sheath tube, and the distance between the distal end port of the reinforcing tube and the distal end port of the pre-bent sheath tube ranges from 100 mm to 200 mm.

[0013] A transporter includes the pre-bent sheath tube described above. The bending angle range of the pre-bent sheath tube is 25° to 65°, and the wall thickness of the pre-bent sheath tube on the large bend side is greater than or equal to the wall thickness on the small bend side.

[0014] The beneficial effects of the present invention are as follows: Compared with the prior art, the present invention provides a pre-bent sheath tube and a transporter, which include an outer layer tube and a reinforcing tube having an axial length. The reinforcing tube is embedded in the outer layer tube; the reinforcing tube includes a plurality of support members and axial connecting members arranged axially. After the support members are connected to the axial connecting members, an arc-shaped tube with a bending angle is formed, so that the reinforcing tube has a bending curvature in the natural state, providing a force to maintain the bending shape for the bending position of the pre-bent sheath tube, thereby avoiding straightening during transportation and long-term storage, and effectively avoiding excessive operations on the sheath tube by medical staff before surgery; at the same time, the reinforcing tube makes the pre-bent sheath tube have stronger anti-bending performance, and can effectively avoid serious deformation of the sheath tube when a large bend occurs, affecting the passage and release of the covered stent. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic structural diagram of the transporter in the first embodiment of the present invention.

[0016] Figure 1a This is a radial cross-sectional view of the pre-bent sheath tube in the first embodiment of the present invention.

[0017] Figure 2 This is a schematic structural diagram of the reinforcing tube in the first embodiment of the present invention.

[0018] Figure 2a This is a schematic structural diagram of the support unit in the first embodiment of the present invention.

[0019] Figure 3 This is a schematic structural diagram of the connection end faces at both ends of the axial connector in the first embodiment of the present invention, which are inclined connection end face structures.

[0020] Figure 4 For the present invention Figure 3 Partial enlarged view of position A.

[0021] Figure 5 This is a schematic structural diagram of the axial connector as a corrugated connector in the first embodiment of the present invention.

[0022] Figure 6 This is a schematic structural diagram of the angles of the wave crest and wave trough of the corrugated connector in the first embodiment of the present invention.

[0023] Figure 7 This is a schematic structural diagram of the reinforcing tube when the support member itself has a bending angle in the second embodiment of the present invention.

[0024] Figure 8 This is a schematic structural diagram of the support member itself having a bending angle in the second embodiment of the present invention.

[0025] Figure 9 This is a schematic structural diagram of the support member including support sheets and circumferential connectors in the third embodiment of the present invention.

[0026] Figure 10 This is a schematic diagram of the support member expanding or contracting along the radial direction in the third embodiment of the present invention.

[0027] Figure 11 This is an unfolded view of the circumferential connector of the support member as a Z-shaped wave in the third embodiment of the present invention.

[0028] Figure 12 This is an unfolded view of the circumferential connector of the support member as a semi-elliptical connector in the third embodiment of the present invention.

[0029] Figure 13 This is a top view of the support unit when the axial connector of the support member is an X-shaped connector in the third embodiment of the present invention.

[0030] Figure 14 This is a top view of the support unit when the axial connector of the support member is a diamond-shaped connector in the third embodiment of the present invention.

[0031] Figure 15 This is a schematic diagram of the bending angle of the diamond-shaped connecting piece in the third embodiment of the present invention.

[0032] Figure 16 This is a schematic diagram of the two transverse connecting surfaces of the diamond-shaped connecting piece in the third embodiment of the present invention being inclined connecting surfaces.

[0033] Figure 17 This is a schematic diagram of the structure in the fourth embodiment of the present invention where four support pieces are provided.

[0034] Figure 18 This is an unfolded schematic diagram of the circumferential connecting piece of the support member in the fourth embodiment of the present invention being a Z-shaped wave.

[0035] Figure 19 This is an unfolded schematic diagram of the circumferential connecting piece of the support member in the fourth embodiment of the present invention being a semi-elliptical connecting piece. Detailed implementation manners

[0036] To better understand the concept of the present application, the following specifically describes the implementation manners of the present application with reference to the accompanying drawings. The following specific embodiments are only partial embodiments of the present application and do not limit the present application.

[0037] For ease of description, spatial relative relationship terms can be used in the text to describe the relationship of one element or feature shown in the figure relative to another element or feature. These relative relationship terms are, for example, "inner", "outer", "inner side", "outer side", "below", "beneath", "above", "upper", etc. Such spatial relative relationship terms are intended to include different orientations of the device in use or operation other than the orientations depicted in the figure. For example, if the device in the figure is flipped, then an element described as "below other elements or features" or "beneath other elements or features" will subsequently be oriented as "above other elements or features" or "upper than other elements or features". Therefore, the exemplary term "below" can include both upper and lower orientations. The device can be oriented otherwise (rotated 90 degrees or in other directions) and the spatial relative relationship descriptors used in the text are accordingly interpreted.

[0038] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0039] In order to more clearly describe the structure of the present application, the terms "proximal end" and "distal end" are defined here as commonly used terms in the field of interventional medicine. Specifically, "distal end" refers to the end away from the operator, and "proximal end" refers to the end close to the operator; "axial" refers to its length direction, and "radial" refers to the direction perpendicular to the "axial"; "large curvature side" refers to the side with a larger curvature radius when the tubular structure is in a curved state, and "small curvature side" refers to the side with a smaller curvature radius when the tubular structure is in a curved state.

[0040] See also Figure 1 In order to facilitate a comprehensive understanding of the membrane rupture system provided by the present application, the structure near the aortic arch is first described. The aorta includes the aortic arch, the ascending aorta and the descending aorta, and one side of the aortic arch is connected to multiple branch branches, one of which is the left subclavian artery. The blood flow flows through the ascending aorta, the aortic arch and the descending aorta in sequence, and when it flows to the aortic arch area, part of the blood flow is shunted into each branch branch. Usually, for aortic dissection or aneurysm involving the aortic arch, during surgical treatment, it is necessary to place a covered stent in the aorta, and place a branch vascular stent in the involved branch branches, such as the left subclavian artery, and extend the branch vascular stent to communicate with the covered stent placed in the aorta, so that the blood flow in the aorta can be shunted into the branch branches. The conveyor 1000 provided in the present application is used to safely convey the coated stent in the blood vessel when the coated stent is placed in the aorta. The pre-bent sheath 100 provided in the present application is usually connected to the handle assembly of the conveyor 1000, and its axial movement is controlled by the handle assembly to release the coated stent. The coated stent is compressed and accommodated in the inner cavity of the pre-bent sheath 100 and released when it reaches the release position; wherein the pre-bent sheath 100 includes at least four layers from the inside to the outside in the radial direction, namely, a PTFE liner tube 13, a spring / braided mesh tube 12, a reinforcement tube and a Pebax outer tube 11.

[0041] Embodiment 1:

[0042] See also Figure 1 and Figure 2, the pre-bent sheath tube 100 provided by the present application includes an outer layer tube 1 with an axial length and a reinforcing tube 2, and the reinforcing tube 2 is embedded in the outer layer tube 1; wherein the PTFE inner lining tube 13, the spring / braided net tube 12, and the Pebax outer tube 11 cover the reinforcing tube 2 to form the outer layer tube 1; the pre-bent sheath from the inside out is respectively the PTFE inner lining tube 13, the spring / braided net tube 12, the reinforcing tube 2, and the Pebax outer tube 11; the spring / braided net tube 12 layer plays a role in increasing the overall support of the pre-bent sheath tube 100, and the reinforcing tube 2 layer is at least provided at the bending position of the pre-bent sheath tube 100, which not only further plays a role in supporting the tube body, but also plays a role in maintaining the bending shape of the bending position of the pre-bent sheath tube 100. Among them, the reinforcing tube 2 includes a plurality of support members 211 arranged along the length direction and an axial connecting member 212. The plurality of support members 211 are arranged at intervals along the axis and are connected by the axial connecting member 212. The support member 211 can provide a radial support force for the pre-bent sheath tube 100, so that when the sheath tube is subjected to the force of stent expansion in the cavity or the force outside the sheath tube, a good radial support effect is provided to avoid deformation of the pre-bent sheath tube 100; the axial connecting member 212 connects the plurality of support members 211 to provide an axial support force, so that the plurality of support members 211 as a whole have a tubular structure; after connection, at least a single axial connecting member 212 connects two adjacent support members 211 to form a support unit 21. The reinforcing tube 2 of the present application can also be understood as being formed by continuously arranging a plurality of support units. Adjacent support units 21 are also connected by an axial connecting member 212 to form a support unit 21; the axial connecting member 212 has elasticity. The axially elastic axial connecting member 212 can provide flexibility while providing axial support force. Compared with the continuously spirally arranged spring tube, it has better flexibility at the position of the axial support member 211. Compared with the continuously spaced spring tube, the axial connecting member 212 can provide axial support force and a certain degree of radial support force at the spaced position; the axial connecting member 212 is configured to make the reinforcing tube 2 have a bending angle in the natural state; the natural state refers to the state after the reinforcing tube 2 is manufactured, before it is embedded in the outer layer tube 1 to form the pre-bent sheath tube 100 and without being subjected to any other force; in this state, the reinforcing tube 2 has a bending angle, so that when the reinforcing tube 2 is embedded in the outer layer tube 1 to form the pre-bent sheath tube 100, it can provide a support force for maintaining the bending of the pre-bent sheath tube 100, thereby ensuring that the pre-bent angle of the pre-bent sheath tube 100 is better maintained during long-term storage or transportation; the axial connecting member 212 itself has a bending angle in the axial direction, so that the two support members 211 connected thereto form a bending angle in the axial direction, that is, a support unit 21 has a bending angle. In the case of continuous arrangement, the reinforcing tube 2 forms a reinforcing tube 2 with a bending angle.

[0043] In this embodiment, please refer to Figure 2a and Figure 3, the support unit 21 includes a first support member 21101 and a second support member 21102 that are adjacently arranged. The axial connecting member 212 includes a first connection end 2121 at the proximal end and a second connection end 2122 at the distal end. The axial connecting member 212 can be arranged at the large bend side 14 and the small bend side 15 of the pipe body on the overall pipe body structure of the reinforcing pipe 2, or can be arranged at both side positions on the circumferential direction of the pipe body between the large bend side 14 and the small bend side 15, or can be arranged simultaneously; it can be understood that the bending structures of the axial support members 211 at the large bend side 14 and the small bend side 15 are different from the bending structures of the support members at both side positions between the large bend side 14 and the small bend side 15, and form bends in two mutually perpendicular planes respectively. Among them, since the support member 211 itself has a thickness, the support member 211 has a proximal end face and a distal end face in the axial direction. The first connection end 2121 is connected to the distal end face of the first support member 21101, and the second connection end 2122 is connected to the proximal end face of the second support member 21102; in this application, an included angle is formed between the two connection end faces where the axial connecting member 212 is connected to the support member 211, aiming to make an included angle also formed after the adjacent two support members 211 are connected to the axial connecting member 212, that is, a single support unit 21 is not in a straight pipe shape, but forms a certain bending angle β2, and then the reinforcing pipe 2 formed by multiple support units 21 also forms a tubular member with a bending angle; in this embodiment, the two connection end faces of the axial connecting member 212 have an included angle β1, which can be that the connection end faces at both ends of the axial connecting member 212 itself are inclined connection end faces; it can also be that the axial connecting member 212 itself is a connecting member with a bending angle, then due to its own bending angle, an included angle β1 will be formed between the two connection end faces at both ends of it; it can be understood that there is an included angle between any cross-sections obtained by radially cutting the arc-shaped pipe fitting. Therefore, in this application, the reinforcing pipe 2 is formed by connecting pipe segments formed by multiple support units 21. If a single support unit 21 has a bending angle, the overall reinforcing pipe 2 has a bending angle; connecting the proximal connection face 2111 and the distal connection face 2112 of the first support member 21101 and the second support member 21102 to the two connection end faces of the axial connecting member 212 with an included angle, then an included angle is formed between the proximal connection face 2111 of the first support member 21101 and the distal connection face 2112 of the second support member 21102 and between the distal connection face 2112 of the first support member 21101 and the proximal connection face 2111 of the second support member 21102. At this time, the support unit 21 has a bending angle,

[0044] In another embodiment, both the proximal connection face 2111 and the distal connection face 2112 of the first support member 21101 and the second support member 21102 are set as inclined connection faces, so that the first support member 21101 and the second support member 21102 are not on the same straight line after being connected to the axial connecting member 212 and have a bending angle.

[0045] In this embodiment, the width and / or thickness of the axial connecting member 212 is less than the width and / or thickness of the support member 211. Such a setting reduces the rigidity of the connecting member. While being able to provide a certain degree of axial support force, it has a certain degree of flexibility, enabling the reinforcement tube 2 to provide not only sufficient bending support force for the pre-bent sheath tube 100 but also a certain degree of flexibility, facilitating the smoother passage of the pre-bent sheath tube 100 through blood vessels. Preferably, both the thickness and width of the axial connecting member 212 can be set to be less than those of the support member 211, for example, connected by a silk thread structure. In another embodiment, only the thickness or width of the axial connecting member 212 can be set to be less than that of the support member 211, which can also make the rigidity of the axial connecting member 212 smaller, enabling the reinforcement tube 2 to be more easily deformed at least at the position of the axial connecting member 212 compared to the position of the support member 211, thereby providing a certain degree of flexibility.

[0046] In this embodiment, please refer to Figure 5 and Figure 6 , the axial connecting member 212 is a corrugated connecting member with a bent waveform. The corrugated connecting member can have elasticity while providing support force. The first connecting end 2121 and the second connecting end 2122 are provided at the ends where the corrugated connecting member is connected to the support member 211. Preferably, the corrugated connecting member can be set to have a varying wave width such that the connecting end faces of the first connecting end 2121 and the second connecting end 2122 form an angle. For example, the wave width at both ends of the corrugated connecting member is larger, and the wave width near the middle position is smaller, so that the inclination angles of the wave rods at both ends are larger, and the connecting end faces of the first connecting end 2121 and the second connecting end 2122 form an angle. Specifically, the corrugated connecting member includes at least two wave crests 2123 and one wave trough 2124. Among them, the two wave crests 2123 face the large bend side 14 of the sheath tube, and the wave trough 2124 faces the small bend side 15 of the sheath tube. Moreover, the wave angles α2 of the two wave crests 2123 are equal and both are greater than the wave angle α3 of the wave trough 2124. In this way, while an angle is formed between the two support members 211 connected to the first connecting end 2121 and the second connecting end 2122 of the corrugated connecting member, due to the wave angle α2 of the two wave crests 2123 being greater than the wave angle α3 of the wave trough 2124, when the two support members 211 on both sides are subjected to a force opposite to the bending direction, when the two wave crests 2123 move to a position close to each other, the two wave crests 2123 abut against each other and cannot continue to deform, thereby ensuring that the reinforcement tube 2 is difficult to continue to deform in the direction opposite to the pre-bent direction, thus better maintaining the pre-bent bending angle.

[0047] In another embodiment, please further refer to Figure 3 and Figure 4, it is possible to set the waveform connecting member to have the same wave width, but the first connecting end 2121 and the second connecting end 2122 have inclined connecting end faces with an angle of α4, so that the connecting end faces of the first connecting end 2121 and the second connecting end 2122 form an included angle α1.

[0048] In this embodiment, the reinforcing tube 2 is provided at the bending position of the pre-bent sheath tube 100 to provide bending support. The bending position of the pre-bent sheath tube 100 is usually located between the distal end and the proximal end, and close to the distal end; preferably, the pipe orifice of the reinforcing tube 2 is provided at a distance of 100 mm to 200 mm from the distal end port of the pre-bent sheath tube 100. This distance is the pipe section set at the bending position of the pre-bent sheath tube 100 and is also the position where the covered stent is provided. Setting the reinforcing tube 2 at this position can first provide a supporting force to maintain the bent state for the bending at this position. Secondly, the setting of an additional layer of the reinforcing tube 2 can help the pre-bent sheath tube 100 have better supporting performance to resist the tension of the stent expanding outward in the sheath tube. Here, the purpose of setting the reinforcing tube at this position on the axis of the pre-bent sheath tube 100 is also that while being opposite to the whole covered stent, the axial position of a single support member 211 is the same as or substantially the same as the axial position of a single stent wave loop when the covered stent is arranged in the pre-bent sheath tube. Thus, since the supporting force and tension of the covered stent itself are provided by the stent wave loops, making the position of the support member 211 opposite to the stent wave loops can enable the support member 211 to directly restrict the expansion of the stent wave loops in the circumferential direction to better maintain the overall shape of the pre-bent sheath tube 100.

[0049] In this embodiment, the bending angle of the pre-bent sheath tube 100 is set to 25° to 65°. Setting this bending angle can ensure that after the pre-bent sheath tube 100 passes through a guide wire with a diameter of 0.035 inches, since the guide wire will exert a straightening force on the pre-bent sheath tube 100 inside the pre-bent sheath tube 100, even in this case of the set angle, it can still ensure that the bending angle of the pre-bent sheath tube 100 can be maintained between 25° and 45°. It can be understood that the bending angle of the reinforcing tube 2 is set to 25° to 65°, and the bending angle of the reinforcing tube 2 satisfies the relationship with the bending angle of a single support unit 21: the bending angle of a single support unit 21 * n = the bending angle of the reinforcing tube 2; where n is the number of the set support units 21.

[0050] In another embodiment, please refer to again Figure 1, in order to ensure that the pre-bent sheath 100 has good pre-bent structure retention ability, the wall thickness of the pre-bent sheath 100 at the large bend side 14 of the tube body is greater than the wall thickness at the small bend side 15; the larger wall thickness has greater rigidity and weaker deformability ability, so that the pre-bent sheath 100 is not easily deformed back to its original state during long-term storage; wherein, in one embodiment, the difference between the wall thickness at the large bend side 14 and the wall thickness at the small bend side 15 is 0.02 mm to 0.1 mm. Here, the difference in wall thickness between the large bend side 14 and the small bend side 15 should not be too large, which will cause the overall flexibility of the pre-bent sheath 100 to deteriorate and is not conducive to delivery within blood vessels.

[0051] Embodiment 2:

[0052] In this embodiment, please refer to Figures 7 - 8 , the structure of the pre-bent sheath 100 is basically the same as that in Embodiment 1. The difference is that the support member 211 includes a proximal connection surface 2111 and a distal connection surface 2112, and there is an included angle between the proximal connection surface 2111 and the distal connection surface 2112. The support member 211 itself has a bending angle, that is, the support member 211 has a bending angle β3 at the large bend side 14 and the small bend side 15; the support member 211 itself is a bent member with a bending angle, which causes an included angle to be formed between the proximal connection surface 2111 and the distal connection surface 2112 of the support member 211. At this time, after the first support member 21101 and the second support member 21102 in a single support unit 21 are connected by the axial connecting member 212, the single support unit 21 has a bending angle. Here, the bending angle of the support member 211 with a bending angle is set according to the bending angle of the pre-bent sheath 100. Assuming that the bending angle of the pre-bent sheath 100 is β0, the included angle between the two connection end faces of the axial connecting member 212 is α1, the set number is X, and the set number of the support members 211 is Y, then the bending angle β3 of a single support member 211 satisfies: β3 = β0 - (α1 * X) / Y; in other embodiments, when the included angle α1 between the two connection end faces of the axial connecting member 212 is 0°, then the bending angle β3 of a single support member 211 satisfies: C° = β0 / Y.

[0053] In this embodiment, the support member 211 itself has a bending angle, so the two connecting end faces of the axial connecting member 212 may not form an included angle. The bending structure of the reinforcing tube 2 is formed by the bending angles of a plurality of support members 211, and the axial connecting member 212 provides elastic deformation ability; preferably, while the support member 211 itself has a bending angle, the two connecting end faces of the axial connecting member 212 also have an included angle at the same time. Then, the axial connecting member 212 can provide a supporting force for maintaining the bending of the pre-bent sheath tube 100 while having elastic deformation ability, and at the same time cooperate with the bending angle of the support member 211 itself, making it easier for the reinforcing tube 2 to form a bending arc structure; further, due to the relatively large rigidity of the bending angle of the support member 211 itself, when the axial connecting member 212 is subjected to a relatively large straightening force, even if the axial connecting member 212 is straightened to a straight state, the bending angle of the support member 211 itself can provide a minimum bending angle to ensure that the pre-bent sheath tube 100 will not straighten back.

[0054] Embodiment Three:

[0055] In this embodiment, please refer to Figures 9 - 10 , the structure of the pre-bent sheath tube 100 is basically the same as that in Embodiment One and Embodiment Two. The difference is that the support member 211 is set to be elastic in the circumferential direction. The support member 211 can expand or contract along the radial direction, and the support member 211 has a circular radial cross-section in both the natural state and the stressed state; thus arranged, the purpose is to make the elastic deformation trend of the support member 211 with a circular cross-section enable the deformation of the pre-bent sheath tube 100 to be controllable and uniformly deformed when the pre-bent sheath tube 100 is subjected to uneven tension or extrusion force; here, when the tubular main body is subjected to a large-angle bending deformation, the bending position will deform and become a flat ellipse. Similarly, when the pre-bent sheath tube 100 passes through a blood vessel with a large bending angle in the human body, a large degree of deformation will also occur at the bending position, becoming a tube body with an elliptical cross-section. At this time, the passing performance of the covered stent provided at the bending position becomes poor, which is not conducive to the passing of the covered stent; and through the elastic setting of the support member 211 with a circular cross-section, in the stressed state, the support member 211 first undergoes a deformation tending to be circular, providing a small amount of buffering, and then ensuring that the tube body still has a circular radial cross-section, so as to ensure that when the pre-bent sheath tube 100 is subjected to a large bending force at the bending position, it is difficult to form an elliptical tube body, thereby enhancing the passing performance of the pre-bent sheath tube 100 at the bending position.

[0056] In this embodiment, the support member 211 is provided with a plurality of support pieces 213 and a circumferential connecting member 214 along the circumferential direction. The support pieces 213 are arranged at intervals along the circumferential direction, and adjacent support pieces 213 are connected by the circumferential connecting member 214. The circumferential connecting member 214 is connected to the support piece 213 to form an annular support member 211. The support pieces 213 are separately arranged to have a deformable gap, and are connected by the circumferential connecting member 214 to keep a circular cross-section; preferably, the circumferential connecting member 214 is an elastic connecting member, so that the support member 211 formed by connecting it with the support piece 213 has elasticity in the circumferential direction, and thus can expand or contract along the radial direction. Specifically, it can be a corrugated connecting member that connects the support pieces 213 respectively. The corrugated connecting member has elasticity due to its own corrugated structure. Therefore, when the support member 211 is stressed, the plurality of support pieces 213 move closer to the center of the circle, and at this time, the circumferential connecting member 214 is stressed and contracts and is extruded. Here, the elastic setting of the circumferential connecting member 214 enables the support member 211 to provide a resilience force when entering a blood vessel segment with a relatively gentle bending degree even after the pre-bent sheath 100 is subjected to a large deformation force when passing through a large-bending blood vessel pipeline, so that the sheath can be restored to the shape before being extruded as much as possible, thereby ensuring better passability for the subsequent release of the covered stent.

[0057] In this embodiment, please continue to refer to Figure 9 , there are at least two support pieces 213, which are respectively arranged at the side positions between the major curvature side 14 and the minor curvature side 15, and partially extend to the major curvature side 14 and the minor curvature side 15. The two support pieces 213 are connected by the circumferential connecting member 214 at the top of the major curvature side 14 and the bottom of the minor curvature side 15; with such a setting, when the pre-bent sheath 100 undergoes a large bend and the tube body is extruded, deformation usually first occurs at the sides of the major curvature side 14 and the minor curvature side 15. Due to the rigidity of the support piece 213 itself and the fact that the support piece 213 is arranged at the sides of the major curvature side 14 and the minor curvature side 15, it can provide good support on both sides to prevent deformation; among them, the circumferential connecting member 214 is arranged at the top of the major curvature side 14 and the bottom of the minor curvature side 15. When the support piece 213 is extruded, the circumferential connecting member 214 retracts, which can provide a certain deformation buffer and resist the force generated by partial bending, and can effectively prevent the bent position of the pre-bent sheath 100 from being flattened to form an elliptical cross-section.

[0058] Specifically, please refer to Figure 11 and 12, the corrugated connecting member may have a continuous Z-shaped wave 2141, which is meanderingly arranged along the circumference of the support member 211, so as to provide support and elasticity between the support sheets 213 in the circumferential direction; in some embodiments, the corrugated connecting member may be only a semi-elliptical connecting member 2142. After the semi-elliptical connecting member 2142 is respectively connected to the support sheets 213 on both sides, the arc portion extends away from the support member 211, so as to be able to cover the gap between adjacent support members 211 and thus provide some supporting force to prevent the pipe body from expanding or collapsing at this part.

[0059] In other embodiments, please refer to Figure 13 , the support sheets 213 are arranged in two separate parts, and only the axial connecting member 212 may be provided without providing the circumferential connecting member 214, wherein the axial connecting member 212 adopts the structure of an X-shaped connecting member 21201; both the first connecting end 2121 and the second connecting end 2122 in the axial direction of the X-shaped connecting member 21201 are each provided with two connecting end faces, and each connecting end face is connected to the proximal connecting surface 2111 or the distal connecting surface 2112 of each support sheet 213. After connection, a gap is formed between the two support sheets 213 of a single support member 211 at the large bend side 14 and the small bend side 15 positions; it can be understood that the X-shaped connecting member 21201 has elasticity in the axial and circumferential directions, and can provide axial supporting force and axial supporting force. Thus, while achieving the effect of simultaneously setting the axial connecting member 212 and the circumferential connecting member 214, the number of connecting members provided is reduced, and the production complexity is reduced, thereby reducing the cost.

[0060] In another embodiment, please refer to Figures 14 - 16 , the support sheets 213 are arranged in two separate parts, and only the circumferential connecting member 214 may be provided without providing the axial connecting member 212, wherein the circumferential connecting member 214 adopts the structure of a rhombic connecting member 21202; the structure of the rhombic connecting member 21202 includes connecting surfaces 212021 located at four corner positions, and the width of the rhombic connecting member 21202 in the transverse direction is greater than the width in the longitudinal direction, and the width D2 in the transverse direction is greater than the width D1 in the circumferential direction of the support sheet 213, so that after the rhombic connecting member 21202 is connected to the support sheet 213, it extends beyond the support sheet 213 in the transverse direction, and the extended part forms a part for axial connection, which is equivalent to the axial connecting member 212 and is used to connect to the rhombic connecting member 21202 provided on the adjacent support member 211; when connecting, the two connecting surfaces 212021 in the longitudinal direction of the rhombic connecting member 21202 are respectively connected to the support sheet 213 in the circumferential direction, and the two connecting surfaces 212021 in the transverse direction are connected to the rhombic connecting member 21202 provided on the adjacent support member 211; thus arranged, the two connecting surfaces 212021 of the rhombic connecting member 21202 in the transverse direction have an included angle, which may be that the rhombic connecting member 21202 has a bending angle or the two transverse connecting surfaces 212021 are inclined connecting surfaces themselves.

[0061] Embodiment 4:

[0062] In this embodiment, please refer to Figures 17 - 19 , the structure of the support member 211 is substantially the same as that in Embodiment 3. The difference is that there are at least four support sheets 213, which are respectively arranged on the major curvature side 14, the minor curvature side 15, and the two side positions between the major curvature side 14 and the minor curvature side 15; with such an arrangement, support sheets 213 are provided at at least four positions of the pre-bent sheath 100, which can provide a certain rigidity to increase the supporting force, and the adjacent support sheets 213 are connected by a circumferential connecting member 214 to provide elasticity in the circumferential direction, so that the support member 211 has the ability to expand or contract axially; compared with the structure of two support sheets 213, the arrangement of four support sheets 213 enables the tube body to preferentially undergo a smaller diameter reduction in multiple different directions to buffer the pressure when the tube body is pressed, and moreover, the simultaneous diameter reduction of the four support sheets 213 can ensure that the compressed support member 211 has a better roundness, so that the pre-bent sheath 100 maintains a better circular cross-section after bending.

[0063] In this embodiment, the axial connecting member 212 can be connected to all four support sheets 213, or can be only connected to the support sheets 213 at the two side positions between the major curvature side 14 and the minor curvature side 15. Avoiding the setting of the axial connecting member 212 at the positions of the major curvature side 14 and the minor curvature side 15 can reduce the stiffness of the pre-bent sheath 100 at this position to a certain extent, thereby reducing the supporting force and providing better bending flexibility.

[0064] The above specific embodiments are only partial embodiments of the present invention and do not limit the present invention. This specification cannot enumerate all embodiments of the inventive concept of the present invention, and some features of the above different embodiments can be mutually replaced or combined. Those skilled in the art can also make simple replacements according to actual needs. The inventive concept of the present invention shall be subject to the claimed protection scope.

Claims

1. A pre-bent sheath tube, characterized in that, It includes an outer layer tube with an axial length and a reinforcing tube, and the reinforcing tube is embedded in the outer layer tube; the reinforcing tube includes a support unit arranged along the length direction, the support unit includes two support members and at least one axial connecting member, and the axial connecting member connects two adjacent support members; the axial connecting member has elasticity; the axial connecting member makes the reinforcing tube have a bending angle at least in the natural state.

2. The pre-bent sheath tube according to claim 1, wherein The axial connecting member includes a first connecting end at the proximal end and a second connecting end at the distal end, and there is an included angle between the connecting end faces of the first connecting end and the second connecting end.

3. The pre-bent sheath tube according to claim 1, wherein The support member includes a proximal connecting face and a distal connecting face, and there is an included angle between the proximal connecting face and the distal connecting face.

4. The pre-bent sheath tube according to claim 3, wherein The support unit includes a first support member and a second support member, and there is an included angle between the proximal connecting face and / or the distal connecting face of the first support member and the distal connecting face and / or the proximal connecting face of the second support member.

5. The pre-bent sheath tube according to any one of claims 1-4, characterized in that, The support member can expand or contract radially, and the support member has a circular radial cross-section in both the natural state and the stressed state.

6. The pre-bent sheath tube according to claim 5, characterized in that, The support member includes a plurality of support sheets arranged circumferentially and a circumferential connecting member, adjacent support sheets are connected by the circumferential connecting member, and the axial connecting member is connected to the support sheet, and the circumferential connecting member has elasticity.

7. The pre-bent sheath tube according to claim 6, characterized in that, In the natural state, the reinforcing tube includes a large bending side and a small bending side, and there are two side positions between the large bending side and the small bending side; at least two support sheets are provided, which are respectively arranged at the side positions and partially extend to the large bending side and the small bending side.

8. The pre-bent sheath tube according to claim 6, wherein, The support member includes four support sheets, and the four support sheets are respectively arranged at the large bending side, the small bending side and the two side positions.

9. The pre-bent sheath tube according to claim 1, wherein The reinforcing tube is arranged between the distal end and the proximal end of the pre-bent sheath tube, and the distance range from the distal end port of the reinforcing tube to the distal end port of the pre-bent sheath tube is 100mm to 200mm.

10. A conveyor, characterized in that, It includes the pre-bent sheath tube according to any one of claims 1-9, the bending angle range of the pre-bent sheath tube is 25° to 65°, and the wall thickness of the pre-bent sheath tube on the large bending side is greater than or equal to the wall thickness on the small bending side.

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