Passive bending pipe and imbedding device
By alternating the arrangement of restrictive structures on the passively bent tube segment, the flexibility and adaptability of the bent tube are increased, solving the problem of insufficient bending flexibility of the bent tube, and achieving better adaptation to human body cavities and reducing the risk of tissue damage.
Patent Information
- Application Number
- CN202423159757.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2026-02-06
- Estimated Expiration
- 2034-12-20
AI Technical Summary
Existing passive bending tubes have poor bending flexibility, making it difficult to accurately reach the target tissue and potentially causing tissue damage.
By alternately arranging the first and second limiting structures on the passively bent pipe section, a staggered arrangement is formed, increasing the flexibility and adaptability of the bent pipe. The cooperation of the snap-fit protrusion and snap-fit groove provides an active gap to achieve better bending capability.
It improves the bending flexibility and adaptability of the passive bending tube, reduces the risk of damage when in contact with human tissue, and ensures that the implantation device can reach the target tissue more smoothly.
Smart Images
Figure CN223873926U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of medical devices, in particular to a passive bending tube and a delivery device. BACKGROUND
[0002] The delivery device is a commonly used medical device, which has an external control and an insertion tube. The external control is used for in-vitro operation to control the insertion of the insertion tube, so that the insertion tube can be inserted into the human body through the body cavity or surgical incision. The insertion tube includes a passive bending tube, and the passive bending tube has a self-adaptive bending function. The current passive bending tube has poor bending flexibility, which makes it difficult for the delivery device to reach the target tissue, and may also cause damage to the tissue when contacting the human tissue. CONTENT OF THE UTILITY MODEL
[0003] The present application provides a passive bending tube and a delivery device, which can solve the problem of poor bending flexibility of the passive bending tube.
[0004] According to an aspect of the present application, a passive bending tube is provided in an embodiment, which includes: a passive bending tube segment, the passive bending tube segment includes a first body and a second body which are arranged adjacent to each other around a tube segment axis; the first side of the first body has a first limiting structure for limiting the change amount of the distance between the first side of the first body and the second side of the second body, and the second side of the first body has a second limiting structure for limiting the change amount of the distance between the second side of the first body and the first side of the second body; the first side is close to one end of the passive bending tube segment, and the second side is close to the other end of the passive bending tube segment; the first limiting structure and the second limiting structure are alternately arranged along the spiral path of the first body, and the first limiting structure and the second limiting structure each include a clamping protrusion and a clamping groove, and the clamping protrusion is matched in the clamping groove to form a limit.
[0005] In one embodiment, the clamping protrusion includes an arm body and a lateral protrusion protruding from the side surface of one side of the arm body, the clamping groove includes a main body groove matched with the arm body and a side wall groove recessed from the groove wall of the main body groove, and the lateral protrusion is matched in the side wall groove; the width difference between the width of the lateral protrusion and the width of the side wall groove forms a movable gap, the movable gap is used for the lateral protrusion to move in the width direction of the first body to meet the bending of the passive bending tube segment, and the width direction of the lateral protrusion and the width direction of the side wall groove are consistent with the width direction of the first body.
[0006] In one embodiment, the protruding directions of the clamping protrusions of the first limiting structure and the clamping protrusions of the second limiting structure are consistent.
[0007] In one embodiment, the lateral protruding direction of the clamping protrusion of the first limiting structure is a first direction, and the lateral protruding direction of the clamping protrusion of the second limiting structure is a second direction, the first direction being consistent with or opposite to the second direction.
[0008] In one embodiment, the clamping protrusion of the first limiting structure protrudes from the side surface of the first side of the first body to the first side, and the clamping protrusion of the second limiting structure protrudes from the side surface of the first side of the second body to the first side.
[0009] In one embodiment, the first limiting structure and the second limiting structure each include a first clamping protrusion, a first clamping groove, a second clamping protrusion, and a second clamping groove, the first clamping protrusion being fitted in the first clamping groove, the second clamping protrusion being fitted in the second clamping groove, the first clamping protrusion and the second clamping protrusion being arranged adjacent to each other and protruding in opposite directions, the protruding direction of the first clamping protrusion of the first limiting structure being opposite to the protruding direction of the first clamping protrusion of the second limiting structure.
[0010] In one embodiment, the lateral protruding direction of the first clamping protrusion is opposite to the lateral protruding direction of the second clamping protrusion, the lateral protruding direction of the first clamping protrusion of the first limiting structure being a third direction, and the lateral protruding direction of the first clamping protrusion of the second limiting structure being a fourth direction, the third direction being consistent with or opposite to the fourth direction.
[0011] In one embodiment, the first clamping protrusion of the first limiting structure protrudes from the side surface of the first side of the first body to the first side, and the second clamping protrusion of the first limiting structure protrudes from the side surface of the second side of the second body to the second side.
[0012] The first clamping protrusion of the second limiting structure protrudes from the side surface of the second side of the first body to the second side, and the second clamping protrusion of the second limiting structure protrudes from the side surface of the first side of the second body to the first side.
[0013] In one embodiment, the pitch of the helical arrangement of the first body and the second body around the axis of the passive curved tube section gradually decreases from the direction of extension of the axis of the passive curved tube section.
[0014] According to another aspect of the present application, in one embodiment, a delivery device is provided, including an external control for extracorporeal operation, and an insertion tube connected with the external control for implantation in the body, the insertion tube including a passive curved tube as described above.
[0015] According to the passive bending tube and the implantation device of the above embodiment, the first limiting structure and the second limiting structure on the passive bending tube segment are alternately arranged along the spiral path of the first main body, so that the first limiting structure and the second limiting structure can be arranged in a staggered manner in the circumferential direction of the passive bending tube segment, that is, the part between two adjacent first limiting structures also has a movable part of the second limiting structure, which improves the bending flexibility of the passive bending tube, and the passive bending tube has better adaptability, which is beneficial to the smooth reaching of the target tissue by the implantation device, and can reduce the possibility of tissue damage caused by the passive bending tube when contacting the human tissue. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 A structural schematic diagram of a passive bending tube of an embodiment;
[0017] Figure 2 An enlarged view of A in the structural schematic diagram of the passive bending tube of an embodiment; Figure 1
[0018] Figure 3 A structural schematic diagram of the spiral arrangement of the first main body and the second main body of an embodiment;
[0019] Figure 4 Another structural schematic diagram of a passive bending tube of an embodiment;
[0020] Figure 5 An enlarged view of B in the structural schematic diagram of the passive bending tube of an embodiment; Figure 4
[0021] A partial structural schematic diagram of an implantation device of an embodiment; Figure 6 BRIEF DESCRIPTION OF DRAWINGS
[0022] 1-first main body; 2-second main body; 3-first limiting structure; 4-second limiting structure; 5-movable gap; 6-lateral protrusion; 7-arm body; 8-lateral wall groove; 9-first clamping protrusion of the first limiting structure; 10-second clamping protrusion of the first limiting structure; 11-first clamping protrusion of the second limiting structure; 12-second clamping protrusion of the second limiting structure; 13-insertion tube; 14-external control.
[0023] DETAILED DESCRIPTION
[0024] The application will be described in further detail below with reference to the drawings. Like elements in different embodiments are denoted by like reference numerals. In the following description, numerous specific details are described to provide a thorough understanding of the application. However, it will be apparent to one skilled in the art that the application can be practiced without these specific details. In other instances, well-known methods have not been described in detail in order not to unnecessarily obscure the application. In addition, well-known structures have not been described in detail in order not to unnecessarily obscure the application.
[0025] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various embodiments. Meanwhile, the steps or actions in the method description can also be sequentially adjusted or changed in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment, and do not mean that the sequence is necessary, unless otherwise stated that a certain sequence must be followed.
[0026] The serial numbers of components in this paper, such as "first", "second", etc., are only used to distinguish the described objects, and do not have any sequence or technical meaning. The "connection" and "coupling" in this paper include direct and indirect connection (coupling) unless otherwise specified.
[0027] Please refer to Figures 1 to 5 The embodiment of the present application provides a passive bending pipe, which comprises a passive bending pipe segment and other functional components as needed, which will be described in detail below.
[0028] The passive bending pipe segment in the embodiment comprises a first body 1 and a second body 2 which are arranged spirally around a pipe segment axis and adjacent to each other; the first body 1 has a first limiting structure 3 on a first side thereof, the first limiting structure 3 being used to limit the variation of the distance between the first side of the first body 1 and a second side of the second body 2, and the first body 1 has a second limiting structure 4 on a second side thereof, the second limiting structure 4 being used to limit the variation of the distance between the second side of the first body 1 and the first side of the second body 2; the first side is close to one end of the passive bending pipe segment, and the second side is close to the other end of the passive bending pipe segment; the first limiting structure 3 and the second limiting structure 4 are arranged alternately along the spiral path of the first body 1, and each of the first limiting structure 3 and the second limiting structure 4 comprises a clamping protrusion and a clamping groove, and the clamping protrusion is matched in the clamping groove to form a limitation.
[0029] The first limiting structure 3 and the second limiting structure 4 on the passive bending pipe segment in the embodiment are alternately arranged along the spiral path of the first body 1, so that the staggered arrangement of the first limiting structure 3 and the second limiting structure 4 in the circumferential direction of the passive bending pipe segment can be formed, that is, the part between two adjacent first limiting structures 3 also has a movable part of the second limiting structure 4, so that the bending flexibility of the passive bending pipe is improved.
[0030] It can be understood that the first body and the second body of the passive bending pipe segment have a spacing change amount, and the bending function of the passive bending pipe segment can be realized through the spacing change amount. The first limiting structure 3 and the second limiting structure 4 in the embodiment can provide a movable space for the bending of the passive bending pipe. The more the distribution of the movable space on the passive bending pipe, the better the bending flexibility of the passive bending pipe. The passive bending pipe segment in the embodiment has the first body 1 and the second body 2 arranged in a spiral around the pipe segment axis. The first body 1 and the second body 2 can be formed by integral cutting. When cutting, two different spiral lines can be used to cut to form the first body 1 and the second body 2 arranged in a spiral. The two different spiral lines arranged adjacent to each other can form adjacent first body 1 and second body 2. The first limiting structure 3 and the second limiting structure 4 in the embodiment are respectively located on the first side and the second side of the first body 1 opposite to each other. The first side and the second side in the embodiment are only used as an example of orientation and do not limit the specific position of the side of the first body 1 or the side of the second body 2. For example, the first limiting structure 3 or the second limiting structure 4 can be all or partially arranged inside the body or all or partially arranged outside the body. The inside of the body in the embodiment refers to the area between the two sides of the body, and the outside of the body refers to the area outside the two sides of the body. The first limiting structure 3 and the second limiting structure 4 are alternately arranged along the spiral path of the first body 1, that is, the center of the first limiting structure 3 and the center of the second limiting structure 4 are alternately arranged along the spiral path of the first body 1. At this time, along the spiral extension path of the first body 1, the first limiting structure 3 on the first side of the first body 1, the second limiting structure 4 on the second side of the first body 1, the first limiting structure 3 on the first side of the first body 1, the second limiting structure 4 on the second side of the first body 1, and so on can be sequentially arranged.
[0031] The first limiting structure 3 and the second limiting structure 4 in the embodiment are alternately arranged along the spiral path of the first body 1, so that there is the second limiting structure 4 between adjacent first limiting structures 3, that is, there is a movable part between adjacent first limiting structures 3, the passive bending pipe has higher movability when bending, and the bending shape of the passive bending pipe is better. Meanwhile, the spacing of the adjacent first limiting structures 3 on the spiral path can be set to a larger value. The limiting structure is formed by cutting, so that the cutting path can be simplified and the machining is more favorable. The number of the clamping protrusions and the clamping grooves in the first limiting structure 3 and the second limiting structure 4 in the embodiment is not limited, and can be one, two or more. The number of the clamping protrusions and the clamping grooves of each limiting structure in the embodiment can be the same or different.
[0032] In an embodiment, as shown in FIG. 6, the clamping protrusion includes an arm body 7 and a lateral protrusion 6 protruding from the side of the arm body 7, and the clamping groove includes a main groove matched with the arm body 7 and a side wall groove 8 recessed from the groove wall of the main groove, and the lateral protrusion 6 is matched in the side wall groove 8. The width difference between the width of the lateral protrusion 6 and the width of the side wall groove 8 forms a movable gap 5, and the movable gap 5 is used for the lateral protrusion 6 to move in the width direction of the first body 1 to meet the bending of the passive bending pipe segment. The width direction of the lateral protrusion 6 and the width direction of the side wall groove 8 are consistent with the width direction of the first body 1. Figure 2 In the embodiment, the first limiting structure 3 and the second limiting structure 4 are alternately arranged along the spiral path of the first body 1, so that the movable gap 5 is more intensive on the spiral path, that is, there is the movable gap 5 corresponding to the second limiting structure 4 between the two movable gaps 5 corresponding to the two adjacent first limiting structures 3 on the spiral path. The passive bending pipe has higher movability when bending, and the bending shape of the passive bending pipe is better. In the embodiment, the width direction of the first body 1 is perpendicular to the extension direction of the spiral path of the body. When the lateral protrusion 6 in the embodiment moves in the width direction of the first body 1, the passive bending pipe segment changes in shape. The larger the movable gap 5 is, the better the deformation ability of the passive bending pipe segment is. However, the movable gap 5 should not be too large, otherwise the controllability of the passive bending pipe segment and the flatness of the outer side surface will be affected. In some embodiments, the clamping protrusion can have an “L” shape structure, and the straight arm of the “L” is the arm body 7, and the other straight arm is the lateral protrusion 6. The clamping groove can also have an “L” shape structure, and the straight arm of the “L” is the main groove, and the other straight arm is the side wall groove 8. However, it is not limited to this. The clamping protrusion and the clamping groove in the embodiment can also be other clamping structures, and the spacing change amount between adjacent ring bodies can be limited.
[0033] In some embodiments, the activity gap 5 can gradually increase from the direction of the axis of the passive bending pipe section. In this way, the bending angle of one end of the passive bending pipe section can be large, and the deformation ability of this end is better, while the bending angle of the other end of the passive bending pipe section is relatively small, which can ensure that the bending pipe has a certain strength and is more conducive to control. In the present embodiment, the end of the passive bending pipe section with a relatively small bending angle can be the end close to the external control 14 of the insertion device. In some application scenarios, the activity gap 5 can also be set to the same size, and when the sizes are the same, the bending pipe is easier to manufacture, or the activity gap 5 can also be partially set to the same size and partially set to different sizes, which can be set according to the required bending shape.
[0034] In one embodiment, as shown in Figures 1-3 , the protruding directions of the clamping protrusions of the first limiting structure 3 and the clamping protrusions of the second limiting structure 4 are consistent. In the present embodiment, the protruding directions of the clamping protrusions of the first limiting structure 3 and the clamping protrusions of the second limiting structure 4 are both parallel to the width direction of the first main body 1, and the substantially same protruding directions in the present embodiment are equivalent to the consistent protruding directions.
[0035] In one embodiment, the protruding directions of the lateral protrusions 6 of the clamping protrusions of the first limiting structure 3 are in a first direction, and the protruding directions of the lateral protrusions 6 of the clamping protrusions of the second limiting structure 4 are in a second direction, and the first direction is opposite to the second direction. At this time, the first limiting structure 3 and the second limiting structure 4 jointly form a better limiting effect. In the present embodiment, the protruding directions of the lateral protrusions 6 are perpendicular to the side surface of the arm body 7. In some application scenarios, the first direction and the second direction can also be consistent.
[0036] In one embodiment, the clamping protrusions of the first limiting structure 3 protrude from the side surface of the first side of the first main body 1 to the first side, and the clamping protrusions of the second limiting structure 4 protrude from the side surface of the first side of the second main body 2 to the first side. At this time, the protruding directions of the clamping protrusions of the first limiting structure 3 and the clamping protrusions of the second limiting structure 4 are consistent. In some embodiments, the clamping protrusions of the first limiting structure 3 can also protrude from the side surface of the second side of the second main body 2 to the second side, and the clamping protrusions of the second limiting structure 4 can protrude from the side surface of the second side of the first main body 1 to the second side.
[0037] In one embodiment, as shown in Figure 4 , Figure 5As shown, the first limiting structure 3 and the second limiting structure 4 each include a first clamping protrusion, a first clamping groove, a second clamping protrusion, and a second clamping groove. The first clamping protrusion is fitted in the first clamping groove, and the second clamping protrusion is fitted in the second clamping groove. The first clamping protrusion and the second clamping protrusion are arranged adjacently and protrude in opposite directions. The protruding direction of the first clamping protrusion 9 of the first limiting structure is opposite to that of the first clamping protrusion 11 of the second limiting structure. Each limiting structure in the embodiment includes two clamping protrusions and two clamping grooves. When the first clamping protrusion and the second clamping protrusion are arranged adjacently and protrude in opposite directions, the movable gaps 5 can be staggered in the width direction, i.e., the distance between the movable gap 5 corresponding to the first clamping protrusion and the first main body 1 is different from the distance between the movable gap 5 corresponding to the second clamping protrusion and the first main body 1. For example, the distance between the movable gap 5 corresponding to the first clamping protrusion and the first main body 1 can be greater than the distance between the movable gap 5 corresponding to the second clamping protrusion and the first main body 1. After the movable gaps 5 are staggered in the width direction, the distribution of the movable gaps 5 in the width direction is also more dense, and the passive bending pipe has a higher degree of flexibility in the width direction. In some embodiments, the protruding directions of the first clamping protrusion 9 of the first limiting structure and the first clamping protrusion 11 of the second limiting structure can also be consistent.
[0038] In an embodiment, the protruding directions of the lateral protrusions 6 of the first clamping protrusion and the second clamping protrusion are opposite. The protruding direction of the lateral protrusion 6 of the first clamping protrusion 9 of the first limiting structure is a third direction, the protruding direction of the lateral protrusion 6 of the first clamping protrusion 11 of the second limiting structure is a fourth direction, and the third direction is consistent with the fourth direction. In some embodiments, the third direction and the fourth direction can also be opposite.
[0039] In an embodiment, the first clamping protrusion 9 of the first limiting structure protrudes from the side surface of the first side of the first main body 1 toward the first side, and the second clamping protrusion 10 of the first limiting structure protrudes from the side surface of the second side of the second main body 2 toward the second side. At this time, the protruding directions of the first clamping protrusion 9 of the first limiting structure and the second clamping protrusion 10 of the first limiting structure are opposite. The first clamping protrusion 11 of the second limiting structure protrudes from the side surface of the second side of the first main body 1 toward the second side, and the second clamping protrusion 12 of the second limiting structure protrudes from the side surface of the first side of the second main body 2 toward the first side. At this time, the protruding directions of the first clamping protrusion 11 of the second limiting structure and the second clamping protrusion 12 of the second limiting structure are opposite, and the protruding directions of the first clamping protrusion 9 of the first limiting structure and the first clamping protrusion 11 of the second limiting structure are also opposite.
[0040] In one embodiment, the pitch of the helical arrangement of the first body 1 and the second body 2 around the passive curved tube segment axis gradually decreases from the direction of extension of the passive curved tube segment axis. The curved deformation of the tube segment with smaller pitch is more active, and when the tube segment with smaller pitch corresponds to the distal end of the passive curved tube, the distal end of the curved tube can adapt to more complex human body cavities. In this embodiment, the distal end is the end away from the external control 14, and the proximal end is the end close to the external control 14. In some application scenarios, the pitch of the helical arrangement of the first body 1 and the second body 2 around the passive curved tube segment axis can also be the same.
[0041] The passive curved tube in this embodiment can also include other structures, such as connecting tube segments at the opposite two ends, which will not be described here.
[0042] In the passive curved tube of the above embodiment, the first limiting structure 3 and the second limiting structure 4 on the passive curved tube segment are alternately arranged along the helical path of the first body 1, so that the first limiting structure 3 and the second limiting structure 4 can be arranged in a staggered manner in the circumferential direction of the passive curved tube segment, that is, the part between the two adjacent first limiting structures 3 also has a movable part of the second limiting structure 4, which improves the bending flexibility of the passive curved tube, and the passive curved tube has better adaptability. The bending shape of the passive curved tube can better adapt to complex human body cavities, which is beneficial to the smooth arrival of the insertion device to the target tissue, and can also reduce the possibility of tissue damage caused by the passive curved tube when contacting the human body tissue. In addition, the spacing between the adjacent first limiting structures 3 in the helical path can be set to a larger value, and the limiting structure is formed by cutting, so that the cutting path can be simplified, which is more conducive to processing.
[0043] Please refer to Figure 6 The present application also provides an insertion device, which includes an external control 14 for external operation, and an insertion tube 13 connected with the external control 14 for placement in the body, and the insertion tube 13 includes the passive curved tube as described above.
[0044] It can be understood that the passive curved tube in this embodiment is the same as the above embodiment, which will not be described here. The insertion device in this embodiment can be, but is not limited to, an endoscope or a sheath device. When it is an endoscope, the insertion device can also include an imaging assembly installed at the distal end of the insertion tube 13, and the passive curved tube is arranged at the distal end of the insertion tube 13. The external control 14 can include a handle. When it is a sheath device, the insertion tube 13 in the insertion device can only include the passive curved tube described above, which is inserted into the human body through the passive curved tube, or the insertion tube 13 can also include other tube segments in addition to the passive curved tube. The external control 14 of the sheath device can include a joint or a handle, etc.
[0045] The first limiting structure 3 and the second limiting structure 4 are alternately arranged along the spiral path of the first main body 1, so that the first limiting structure 3 and the second limiting structure 4 are arranged in a staggered manner in the circumferential direction of the passive bending pipe segment, that is, the part between two adjacent first limiting structures 3 also has a movable part of the second limiting structure 4, which improves the bending flexibility of the passive bending pipe, the adaptability of the passive bending pipe is better, and the bending mode of the passive bending pipe can better adapt to the complex human body cavity, which is beneficial to the smooth arrival of the implanting device to the target tissue, and can also reduce the possibility of tissue damage caused by the passive bending pipe when contacting with the human body tissue.
[0046] The above application uses specific examples to illustrate the present application, which is only used to help understand the present application and does not limit the present application. For those skilled in the art to which the present application belongs, according to the idea of the present application, a number of simple deductions, deformations or substitutions can be made.
Claims
1. A passive bend pipe, characterized in that The application relates to a passive curved pipe section comprising a first body and a second body spirally arranged along a pipe section axis and adjacent to each other; the first body has a first side with a first limiting structure for limiting the distance variation between the first side of the first body and the second side of the second body, and a second side with a second limiting structure for limiting the distance variation between the second side of the first body and the first side of the second body; the first side is close to one end of the passive curved pipe section, and the second side is close to the other end of the passive curved pipe section; the first limiting structure and the second limiting structure are alternately arranged along the spiral path of the first body, and each of the first limiting structure and the second limiting structure comprises a clamping protrusion and a clamping groove. The clamping protrusion comprises an arm body and a lateral protrusion protruding from the side surface of the arm body, the clamping groove comprises a main groove matched with the arm body and a side wall groove recessed from the groove wall of the main groove, and the lateral protrusion is matched in the side wall groove; the width difference between the width of the lateral protrusion and the width of the side wall groove forms a movable gap, the movable gap is used for the lateral protrusion to move in the width direction of the first body to meet the bending of the passive curved pipe section, and the width direction of the lateral protrusion and the width direction of the side wall groove are consistent with the width direction of the first body.
2. The passive elbow tube of claim 1, wherein, The protruding directions of the clamping protrusions of the first limiting structure and the second limiting structure are consistent.
3. The passive elbow tube of claim 2, wherein, The protruding directions of the lateral protrusions of the clamping protrusions of the first limiting structure and the second limiting structure are consistent or opposite.
4. The passive elbow tube of claim 3, wherein, The clamping protrusions of the first limiting structure protrude from the side surface of the first side of the first body to the first side, and the clamping protrusions of the second limiting structure protrude from the side surface of the first side of the second body to the first side.
5. The passive elbow tube of claim 3, wherein, The first limiting structure and the second limiting structure each comprise a first clamping protrusion, a first clamping groove, a second clamping protrusion and a second clamping groove, the first clamping protrusion is matched in the first clamping groove, the second clamping protrusion is matched in the second clamping groove, the first clamping protrusion and the second clamping protrusion are arranged adjacent to each other and have opposite protruding directions, and the protruding directions of the first clamping protrusions of the first limiting structure and the second limiting structure are opposite.
6. The passive elbow tube of claim 2, wherein, The protruding directions of the lateral protrusions of the first clamping protrusion and the second clamping protrusion are opposite, the protruding directions of the lateral protrusions of the first clamping protrusions of the first limiting structure and the second limiting structure are consistent or opposite.
7. The passive elbow tube of claim 6, wherein, 8. The passive elbow tube of claim 6, wherein, The first clamping protrusion of the first limiting structure protrudes from the side surface of the first side of the first body to the first side, and the second clamping protrusion of the first limiting structure protrudes from the side surface of the second side of the second body to the second side; The first clamping protrusion of the second limiting structure protrudes from the side surface of the second side of the first body to the second side, and the second clamping protrusion of the second limiting structure protrudes from the side surface of the first side of the second body to the first side.
9. Passive bend according to any of claims 1-8, characterized in that The pitch of the helical arrangement of the first body and the second body around the passive curved tube segment axis gradually decreases from the direction of extension of the axis of the passive curved tube segment.
10. An implant device, characterized by An insertion tube for in-vivo placement is connected to the external control for ex-vivo operation, the insertion tube comprising a passive curved tube as claimed in any of claims 1-9.