Medical catheter

Abstract

The present application relates to the technical field of medical catheter, in particular to a pull wire structure of a medical catheter. The pull wire and the anti-extraction block of the pull wire structure are welded and fixed, and the anti-extraction block is provided with a welding groove. The distal end of the pull wire is welded with the groove sidewall of the welding groove. Since at least a part of the distal end of the pull wire is in the welding groove, the welding area of the distal end of the pull wire with the groove sidewall of the welding groove is larger, and the tensile strength after welding is higher. The welding of the pull wire and the anti-extraction block ensures the tensile strength between the anti-extraction block and the pull wire. The anti-extraction block is limited from being extracted from the pipe body by the stop of the anti-extraction block and the pipe body, so the pull wire is also limited from being extracted from the pipe body. The stop mode has higher tensile strength, thereby improving the overall tensile strength of the pull wire. In addition, the side opening of the welding groove can expose the position of the distal end of the pull wire and the groove sidewall of the welding groove to be welded, so as to align the position to be welded during welding, thereby improving the welding efficiency.

Description

Technical Field

[0001] This invention relates to the field of medical catheter technology, and more specifically to the drawstring structure of medical catheters. Background Technology

[0002] As interventional medical devices, medical catheters often require bending control during use. Currently, bending control is generally achieved by tightening and loosening the pull cord located in the distal bending section of the corresponding catheter body. The pull cords can be installed in pairs, located on opposite sides of the distal bending section radially. Tightening one pull cord and loosening the other will cause the distal bending section to bend towards the tightened side. In existing catheters, the distal ends of the pull cords are usually fixed to the catheter body with adhesive, resulting in low bonding strength. Due to the low bonding strength at the distal end of the pull cord, the tensile strength of the pull cord is also low. Summary of the Invention

[0003] This invention provides a drawstring structure for medical catheters to improve the tensile strength of the drawstring.

[0004] In addition, the present invention aims to provide a medical catheter using the above-described draw wire structure.

[0005] In one embodiment, a pull cord structure for a medical catheter is provided, including a pull cord and an anti-dislodgement block; the pull cord is used to be introduced into the body of the medical catheter, and the pull cord has a distal end;

[0006] The anti-detachment block has a welding groove, and the distal end of the pull wire is inserted into the welding groove and welded to the side wall of the welding groove to form a side wall weld; the anti-detachment block has a blocking support surface, which is used to block the tube body in the extension direction of the pull wire to limit the pull wire from coming out of the tube body;

[0007] The welding groove has a through-hole and a side opening. The through-hole allows the pull wire to pass through in the direction of the pull wire's extension, and the side opening exposes the position where the distal end of the pull wire is welded to the side wall of the welding groove before welding.

[0008] In a further embodiment, the welding groove has a bottom wall opposite to the through-hole, the bottom wall of the groove is welded to the distal end of the pull wire to form a bottom wall weld, and the bottom wall weld intersects with the side wall weld.

[0009] Furthermore, in one embodiment, there are two sidewall welds, which are respectively connected to both ends of the bottom wall weld, so that the two sidewall welds and the bottom wall weld are arranged in a U-shape.

[0010] In another embodiment, a portion of the distal end of the pull wire extends out of the welding groove through the side opening.

[0011] Furthermore, the extension direction of the sidewall weld is consistent with the extension direction of the pull wire.

[0012] In another embodiment, the anti-detachment block is fixed to the pull wire by laser welding.

[0013] Furthermore, in one embodiment, the overlapping area of ​​the anti-detachment block and the adjacent weld point at the pull wire welding point is not less than 1 / 3 and not greater than 1 / 2 of the weld point area.

[0014] In a further embodiment, the pull cable includes a cable body and an adapter tube, the adapter tube being located at the distal end of the pull cable, the cable body having a distal end, the distal end of the cable body being inserted into the adapter tube and fixed thereto, and the pull cable being welded and fixed to the anti-detachment block through the adapter tube.

[0015] Furthermore, in one embodiment, the distal end of the line body and the adapter tube are welded together by at least two weld points spaced apart in the extension direction of the adapter tube.

[0016] Furthermore, in one embodiment, the length of the adapter pipe is L, and the distance between any of the solder joints and the end face of the adapter pipe is greater than or equal to L / 5.

[0017] In a second aspect, one embodiment provides a pull cord structure for a medical catheter, including a pull cord and an anti-dislodgement block; the pull cord is used to be introduced into the body of the medical catheter, and the pull cord has a distal end; the anti-dislodgement block is fixed to the distal end of the pull cord, and the anti-dislodgement block has a blocking support surface, which is used to block the tube body in the extension direction of the pull cord to limit the pull cord from dislodging from the tube body;

[0018] The anti-detachment block has a welding hole with an opening for the pull wire to pass through in the extension direction of the pull wire. The sidewall of the welding hole includes a welding portion, at least a portion of which extends in the same direction as the extension direction of the welding hole. The welding portion is used to weld the sidewall of the welding hole to the distal end of the pull wire during welding.

[0019] In another embodiment, the anti-detachment block is fixed to the pull wire by laser welding.

[0020] Furthermore, in one embodiment, the overlapping area of ​​the anti-detachment block and the adjacent weld point at the pull wire welding point is not less than 1 / 3 and not greater than 1 / 2 of the weld point area.

[0021] In a further embodiment, the pull cable includes a cable body and an adapter tube, the adapter tube being located at the distal end of the pull cable, the cable body having a distal end, the distal end of the cable body being inserted into the adapter tube and fixed thereto, and the pull cable being welded and fixed to the anti-detachment block through the adapter tube.

[0022] Furthermore, in one embodiment, the distal end of the line body and the adapter tube are welded together by at least two weld points spaced apart in the extension direction of the adapter tube.

[0023] Furthermore, in one embodiment, the length of the adapter pipe is L, and the distance between any of the solder joints and the end face of the adapter pipe is greater than or equal to L / 5.

[0024] Thirdly, in one embodiment, a medical catheter is provided, including a tube body and a pull-wire structure. The tube body includes a distal bending section, and the pull-wire structure is the pull-wire structure of the medical catheter described in any of the above embodiments. The anti-dislodgement block is mounted on the tube body, and the pull-wire structure is used to drive the distal bending section to bend.

[0025] In a further embodiment, the pipe body has a pull wire through hole and an anti-detachment block mounting groove. The pull wire passes through the pull wire through hole, and the anti-detachment block mounting groove communicates with the pull wire through hole. The anti-detachment block mounting groove is filled with a filling medium for fixing the anti-detachment block, and the anti-detachment block is located in the filling medium.

[0026] According to the above embodiments of the medical catheter pull-wire structure, the pull-wire and the anti-detachment block of the pull-wire structure are welded and fixed, and the anti-detachment block is provided with a welding groove. The distal end of the pull-wire is welded to the side wall of the welding groove. Since at least a portion of the distal end of the pull-wire is in the welding groove, the welding area between the distal end of the pull-wire and the side wall of the welding groove is large, resulting in higher tensile strength after welding. The blocking support surface on the anti-detachment block can block the tube body in the pull-wire extension direction, restricting the separation of the anti-detachment block from the tube body, thus restricting the pull-wire from coming out of the tube body. Welding the pull-wire and the anti-detachment block results in higher tensile strength between the anti-detachment block and the pull-wire. The anti-detachment block and the tube body block and restrict the anti-detachment block from coming out of the tube body. Compared with the adhesive method, the blocking method used in this application allows the anti-detachment block to withstand greater tensile force, resulting in higher tensile strength, thereby improving the overall tensile strength of the pull-wire. In addition, the side opening of the welding groove can expose the position where the distal end of the pull-wire and the side wall of the welding groove are to be welded, making it easier to align the position to be welded during welding and improving welding efficiency.

[0027] Furthermore, in the medical catheter pull-wire structure according to some of the above embodiments, the pull-wire and the anti-detachment block of the pull-wire structure are welded and fixed, and the anti-detachment block is provided with a welding hole. The distal end of the pull-wire is welded to the sidewall of the welding hole. Since at least a portion of the distal end of the pull-wire is inside the welding hole, the welding area between the distal end of the pull-wire and the sidewall of the welding hole is large, resulting in higher tensile strength after welding. The blocking support surface on the anti-detachment block can block the tube body in the pull-wire extension direction, restricting the separation of the anti-detachment block from the tube body, thus restricting the pull-wire from detaching from the tube body. Welding the pull-wire and the anti-detachment block results in higher tensile strength between the anti-detachment block and the pull-wire. The anti-detachment block and the tube body block and restrict the anti-detachment block from detaching from the tube body. Compared with the adhesive method, the blocking method used in this application allows the anti-detachment block to withstand greater tensile force, resulting in higher tensile strength, thereby improving the overall tensile strength of the pull-wire. The welding portion in the sidewall of the welding hole can be easily welded outside the welding hole, improving welding efficiency. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of a medical catheter in one embodiment;

[0029] Figure 2 This is a schematic diagram of the installation structure of the wire-drawing structure and the pipe body in one embodiment;

[0030] Figure 3 This is a schematic diagram of a portion of the draw wire structure and another installation structure of the tube body in one embodiment;

[0031] Figure 4 This is a cross-sectional view of the wire-drawing structure after it has been installed onto the pipe body in one embodiment.

[0032] Figure 5 This is a schematic diagram of the draw wire structure in one embodiment;

[0033] Figure 6 for Figure 5 Top view;

[0034] Figure 7 for Figure 5 The left view;

[0035] Figure 8 An exploded view of the drawbar structure in one embodiment;

[0036] Figure 9 This is a schematic diagram of the structure of the transfer tube and the anti-detachment block in one embodiment;

[0037] Figure 10 This is a schematic diagram of the anti-detachment block in one embodiment;

[0038] Figure 11 This is a schematic diagram of the anti-detachment block and pull wire in another embodiment;

[0039] Figure 12 This is a top view of the drawbar structure in one embodiment;

[0040] Figure 13 This is a schematic diagram of the perforated anti-detachment block and pull wire in one embodiment;

[0041] Figure 14 This is an isometric view of a perforated anti-detachment block and a pull wire in one embodiment.

[0042] List of feature names corresponding to the attached figures: 1. Pipe body; 11. Pull wire perforation; 12. Distal bending section; 13. Distal end of pipe body; 14. Anti-detachment block mounting groove; 2. Pull wire control handle; 3. Pull wire; 31. Distal end of pull wire; 32. Wire body; 321. Distal end of wire body; 33. Adapter pipe; 34. Weld point; 4. Anti-detachment block; 41. Welding groove; 42. Through port; 43. Side opening; 44. Blocking support surface; 45. Welding hole; 46. Welding part; 51. Side wall weld; 52. Bottom wall weld.

[0043] Explanation of reference numerals in parentheses in the accompanying drawings: The feature referred to by the reference numerals in parentheses in the accompanying drawings is the feature represented by both the number inside the parentheses and the number outside the parentheses. Detailed Implementation

[0044] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of this application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to this application are not shown or described in the specification. This is to avoid obscuring the core parts of this application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0045] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0046] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0047] Currently, many types of medical catheters require bending control during use. However, the tensile strength of the pull cord in these catheters is relatively low. This application presents a novel pull cord structure, in which an anti-dislodgement block is welded to the distal end of the pull cord, effectively blocking the catheter body and achieving a breakthrough in tensile strength. The pull cord structure and the overall structure of the medical catheter are described in detail below with reference to the accompanying drawings.

[0048] In some embodiments, please refer to Figures 1 to 4 The medical catheter includes a tube body 1, a pull-wire structure and a pull-wire control handle 2. The pull-wire structure of the medical catheter includes a pull-wire 3 and an anti-dislodgement block 4.

[0049] The tube body 1 has a draw wire hole 11, and the draw wire 3 is used to be introduced into the draw wire hole 11 of the tube body 1. Here, the draw wire 3 being introduced into the tube body 1 includes all or part of the draw wire 3 being introduced into the draw wire hole 11 of the tube body 1.

[0050] The pull cable 3 has a distal end 31 and a proximal end (not shown in the figure). The distal end 31 is led into the tube body 1 through the pull cable perforation 11, while the proximal end is outside the tube body 1 and connected to the pull cable control handle 2. By operating the pull cable control handle 2, the pull cable 3 can be pulled. The tube body 1 includes a distal bending section 12, and the pull cable structure is used to bend the distal bending section 12. In one embodiment, the distal bending section 12 may be located on one side of the distal end 13 of the tube body; in other embodiments, the distal end 13 of the tube body may also form the distal end of the distal bending section 12. In some embodiments, the tube body 1 is a multi-lumen tube body.

[0051] It should be noted that, in this application, "proximal end" refers to the end closest to the pull cable control handle 2, and "distal end" refers to the end furthest from the pull cable control handle 2. The corresponding "end" refers to the region at the end point, which can be understood as a region of a certain length at the end point, and is not limited to the end face. Of course, "close to the pull cable control handle 2" also includes the case where it is connected to the pull cable control handle 2.

[0052] When there is only one distal bending section 12, the distal end 31 of the pull wire can be located either at the distal end of the distal bending section 12 or at the distal end 13 of the pipe body. This allows the distal bending section 12 to bend according to the designed arc after the pull wire 3 is pulled. Of course, the number of distal bending sections 12 is not limited to one; the pipe body 1 can include at least two distal bending sections 12, and the bending arc and direction of each distal bending section 12 can be the same or different. Typically, each distal bending section 12 requires a set of pull wires 3 for bending control. However, in some special cases, two distal bending sections 12 can share a set of pull wires 3.

[0053] Because the pull wire 3 needs to withstand significant tensile force, the connection method between the distal end 31 of the pull wire and the pipe body 1 must meet tensile strength requirements. To improve the tensile strength of the pull wire 3, a special welding structure is used between the pull wire 3 and the anti-detachment block 4. For some embodiments, please refer to... Figures 5 to 8 The anti-detachment block 4 has a welding groove 41. The distal end 31 of the pull wire is inserted into the welding groove 41 and welded to the sidewall of the welding groove 41, so that the weld between the distal end 31 of the pull wire and the anti-detachment block 4 includes at least a sidewall weld 51. This results in a larger welding area between the welding groove 41 and the distal end 31 of the pull wire, improving the welding strength between the distal end 31 of the pull wire and the anti-detachment block 4. The sidewall of the welding groove 41 is welded to the outer peripheral surface of the distal end 31 of the pull wire to form a sidewall weld 51. In one embodiment, the sidewall weld 51 is a continuous weld, and the extension direction of the sidewall weld 51 is consistent with the extension direction of the pull wire 3. It should be noted that the consistent extension direction described in this embodiment includes not only the same extension direction, but also the case where the extension direction has a small angular deviation, and the case where the side wall weld 51 extends along a curve, such as when the side wall weld 51 is wavy. In this case, the extension direction of the side wall weld 51 should be understood as the extension direction of the straight line where the beginning and end of the side wall weld 51 are located. For another example, if the extension direction of the side wall weld 51 has a small angular deviation from the extension direction of the pull wire 3, it should also be understood that the two extension directions are consistent. The small angle here is usually 0°-45° depending on the actual needs. For yet another example, if the side wall weld 51 is wedge-shaped, it should also be considered that the extension direction of the side wall weld 51 is consistent with the extension direction of the pull wire 3.

[0054] In some other embodiments, the sidewall weld 51 may also be a plurality of spot welds arranged at intervals.

[0055] Please refer to Figures 8 to 9 The welding groove 41 has a through port 42 and a side opening 43. The through port 42 allows the pull wire 3 to pass through in the extension direction of the pull wire 3. The side opening 43 can expose the position where the distal end 31 of the pull wire and the side wall of the welding groove 41 are welded before welding, so as to facilitate welding of the pull wire 3 and the anti-detachment block 4.

[0056] The welding groove 41 can take any feasible form, for example, please refer to Figure 11 One side opening 43 is provided for the welding groove 41; for example, please refer to Figures 5 to 8 The welding groove 41 has two side openings 43, which are arranged opposite to each other. In this case, the welding groove 41 is a U-shaped through groove. Alternatively, the welding groove 41 can also be a C-shaped through groove.

[0057] Please refer to Figure 4 and Figure 8 The anti-detachment block 4 has a blocking support surface 44, which blocks the tube body 1 in the extension direction of the pull wire 3 to prevent the pull wire 3 from detaching from the tube body 1. The anti-detachment block 4 can be implemented in various ways:

[0058] For example, a hole extending radially along the pipe body 1 can be opened on the pipe body 1. The anti-detachment block 4 is rod-shaped. The anti-detachment block 4 is inserted into the hole. The anti-detachment block 4 directly engages with the pipe body 1 in the extension direction of the pull wire 3. Of course, in order to facilitate the connection between the anti-detachment block 4 and the pull wire 3, the pull wire 3 should be inserted into the pipe body 1 and then welded to the anti-detachment block 4 after it comes out of the pipe body 1. Then the anti-detachment block 4 and the pull wire 3 are installed into the pipe body 1.

[0059] For example, please refer to Figures 2 to 4 The pipe body 1 is provided with an anti-detachment block mounting groove 14. The pull wire 3 is inserted into the pull wire through hole 11. The anti-detachment block mounting groove 14 is connected to the pull wire through hole 11. The anti-detachment block mounting groove 14 is filled with a filling medium (not shown in the figure), and the anti-detachment block 4 is placed in the filling medium. The specific fixing method between the anti-detachment block 4 and the filling medium is as follows: the anti-detachment block 4 is placed in the anti-detachment block mounting groove 14 and the position is confirmed. Then, the filling medium is injected. After the filling medium cures, the anti-detachment block 4 is fixed. The filling medium can be glue, which is squeezed into the anti-detachment block mounting groove; of course, the filling medium can also be other materials such as plastic, which can be injected into the anti-detachment block mounting groove 14 by injection molding. To facilitate assembly and improve assembly accuracy, the anti-detachment block 4 is spaced from the groove wall of the anti-detachment block mounting groove 14 on both sides of the extension direction of the tube body 1. This also facilitates the entry of the filling medium. When the pull wire 3 is pulled, the filling medium between the anti-detachment block 4 and the groove wall of the anti-detachment block mounting groove 14 can also prevent the anti-detachment block 4 from damaging the tube body 1.

[0060] Of course, in some other embodiments, when the materials of the anti-detachment block 4 and the pipe body 1 change, the anti-detachment block 4 can also be made to contact the pipe body 1. In this case, the anti-detachment block mounting groove 14 can be fixed without filling with a medium. In some other embodiments, in order to prevent the anti-detachment block 4 from moving, the anti-detachment block 4 can also be welded to the pipe body 1. In some other embodiments, in order to prevent the anti-detachment block 4 from falling off the anti-detachment block mounting groove 14 after the pull wire 3 breaks, a safety rope connecting the anti-detachment block 4 is provided inside the pipe body 1. The safety rope extends to the far end 13 of the pipe body and is fixed thereon. In this way, even if the pull wire 3 breaks, the anti-detachment block 4 is kept in the anti-detachment block mounting groove 14 under the action of the filling medium and the safety rope.

[0061] Please refer to Figure 4 When the pull wire 3 extends into the pull wire through hole 11, the anti-detachment block 4 blocks the tube body 1. In fact, it blocks the opening of the pull wire through hole 11 on the groove wall of the anti-detachment block mounting groove 14. The maximum cross-sectional dimension of the anti-detachment block 4 is larger than the cross-sectional dimension of the pull wire through hole 11, so the anti-detachment block 4 cannot enter the pull wire through hole 11, thus achieving the blocking of the tube body 1 by the anti-detachment block 4.

[0062] It should be noted that the blocking in this application includes both mutual blocking after contact and indirect blocking without direct contact. For example, in the above embodiment, there is a filling medium between the anti-detachment block 4 and the tube body 1. In this case, the anti-detachment block 4 and the tube body 1 block each other in the extension direction of the pull wire 3. However, in the extension direction of the pull wire 3, the blocking support surface 44 on the anti-detachment block 4 does not directly contact the tube body 1 for blocking. As another example, in the other embodiments mentioned above, the anti-detachment block 4 can also contact the tube body 1 for blocking. In this case, the blocking support surface 44 contacts the groove wall surface of the anti-detachment block mounting groove 14 on the tube body 1. The groove wall surface of the anti-detachment block mounting groove 14 blocks and cooperates with the blocking support surface 44 in the extension direction of the pull wire 3. That is to say, the blocking mentioned in this application, unless otherwise specified, is not limited to the blocking of the anti-detachment block 4 in contact with the tube body 1, nor is it limited to the form of non-contact blocking. It can be understood as including both the blocking support surface 44 directly contacting the tube body 1 for blocking and the blocking support surface 44 and the tube body 1 achieving non-contact blocking through other contact. In addition to filling with a medium, non-contact blocking can also be achieved by adding a gasket between the anti-detachment block 4 and the tube body 1 to prevent the tube body 1 from being damaged by the anti-detachment block 4.

[0063] In the medical catheter of this application, the pull wire 3 of the pull wire structure can be adopted in any feasible manner. However, since the pull wire 3 needs to be welded and fixed to the anti-dislodgement block 4, the material of the pull wire 3 is suitable to be a weldable material. The pull wire 3 and the anti-dislodgement block 4 can be made of the same material or different materials. For example, the pull wire 3 and the anti-dislodgement block 4 can both be stainless steel, or both are nickel-titanium, or both are carbon steel. For another example, the pull wire 3 and the anti-dislodgement block 4 can be welded from pearlitic steel and austenitic steel respectively, or copper and steel respectively, or aluminum and steel respectively. In one embodiment, the anti-dislodgement block 4 is a stainless steel metal block.

[0064] In some embodiments, the medical catheter can be either a catheter or a sheath. Regarding the shape of the anti-detachment block 4, it can be a cylinder, rectangle, ellipse, ellipsoid, or plate, or an irregular block. In one embodiment, please refer to... Figure 2 The anti-detachment block 45 is made of plate-shaped blocks.

[0065] In the pull wire structure of this application, the pull wire 3 and the anti-detachment block 4 are fixed by welding, and at least a portion of the distal end 31 of the pull wire is located in the welding groove 41. The extension direction of the side wall weld 51 is consistent with the extension direction of the pull wire 3, ensuring that the pull wire 3 and the anti-detachment block 4 have a sufficiently large welding area, improving the welding strength of the pull wire 3 and the anti-detachment block 4, making it difficult for the pull wire 3 and the anti-detachment block 4 to separate, and thus increasing the tensile strength. Regarding the installation method of the anti-detachment block 4, the anti-detachment block 4 blocks the tube body 1 in the extension direction of the pull wire 3 by blocking the support surface 44, restricting the separation of the anti-detachment block 4 from the tube body 1, thereby restricting the pull wire 3 from coming out of the tube body 1. Since the way the anti-detachment block 4 blocks the tube body 1 can withstand greater tensile force, this improves the tensile strength of the distal end 31 of the pull wire, and thus improves the overall tensile strength of the pull wire 3.

[0066] To further increase the tensile strength of draw wire 3, please refer to... Figure 5 and Figure 8 The welding groove 41 has a bottom wall opposite to the through-hole 42. The bottom wall is welded to the distal end 31 of the pull wire, so that the weld between the distal end 31 of the pull wire and the anti-detachment block 4 includes a bottom wall weld 52, which intersects with the side wall weld 51. The bottom wall weld 52 further increases the welding area between the pull wire 3 and the anti-detachment block 4. In some other embodiments, the side opening 43 of the welding groove 41 may be provided only once. In this case, the bottom wall of the groove is opposite to the side opening 43, and the welding groove 41 has a through-hole opposite to the through-hole 42 in the extension direction of the pull wire 3. In this case, the welding groove 41 is welded to the pull wire 3 through two side walls that form the side opening 43, and there are two side wall welds 51.

[0067] Furthermore, in one embodiment, please refer to Figure 5There are two sidewall welds 51, which connect to both ends of the bottom wall weld 52, forming a U-shape. The two sidewall welds 51 and one bottom wall weld 52 create a U-shape, and the circumferential welding increases the welding area, further improving the welding strength between the pull wire 3 and the anti-detachment block 4. In some other embodiments, only one sidewall weld 51 may be provided.

[0068] In one embodiment, please refer to Figures 6 to 9 A portion of the distal end 31 of the pull wire extends out of the welding groove 41 through the side opening 43. Specifically, in one embodiment, the orientation of the side opening 43 is perpendicular to the orientation of the through opening 42, and the side opening 43 communicates with the through opening 42. In one embodiment, there are two side openings 43 facing each other. In this case, the outer diameter of the pull wire 3 is larger than the groove width of the welding groove 41. A portion of the distal end 31 of the pull wire extends out of one side opening 43, and another portion extends out of the other side opening 43. When welding the pull wire 3 and the anti-detachment block 4, the pull wire 3 and the anti-detachment block 4 can be welded from one side opening 43, or the pull wire 3 can be welded from one side opening 43 and then welded from the other side opening 43. In some other embodiments, there is only one side opening 43. In some other embodiments, the distal end 31 of the pull wire may not extend out of the side opening 43. In this case, the wire diameter of the distal end 31 of the pull wire is smaller than the groove width of the welding groove 43 (the groove width is the distance between the two side openings).

[0069] For further details, please refer to... Figure 3 and Figure 4 Because the pull wire 3 is easily melted during welding with the anti-detachment block 4, to improve welding quality, the pull wire 3 includes a wire body 32 and an adapter pipe 33. The adapter pipe 33 is located at the distal end 31 of the pull wire, and the wire body 32 has a distal end 321. The distal end 321 is inserted into and fixed to the adapter pipe 33. The pull wire 3 is welded to the anti-detachment block 4 through the adapter pipe 33. By welding the adapter pipe 33 to the anti-detachment block 4, the wire body 32 is less likely to melt, reducing the welding process requirements and improving the welding strength. For some other embodiments, please refer to... Figure 12 The pull wire 3 may also consist only of the wire body 32, which is directly welded to the anti-detachment block 4. In one embodiment, after the wire body 32 is welded and fixed to the adapter pipe 33, the pull wire 3 is then threaded into the pipe body, and the distal end 31 of the pull wire is then welded and fixed to the anti-detachment block 4. Alternatively, after welding the distal end 31 of the pull wire to the anti-detachment block 4, the pull wire 3 is threaded into the pipe body 1 from the anti-detachment block mounting groove 14, so that the proximal end of the pull wire exits from the proximal end of the pipe body 1.

[0070] Specifically, the wire body 32 is made of round steel wire, and the connecting pipe 33 is made of round steel pipe. In some other embodiments, the wire body 32 may be made of flat wire, and the steel pipe may be made of flat pipe.

[0071] Furthermore, to further prevent the fusion wire 32 from breaking during welding, please refer to... Figure 4 and Figure 5 In some embodiments, the distal end 321 of the wire body and the adapter pipe 33 are welded together by at least two weld points 34 spaced apart along the extension direction of the adapter pipe 33. Welding the wire body 32 and the adapter pipe 33 by at least two weld points 34 avoids continuous welding of the wire body 32, prevents the wire body 32 from melting, maintains the continuity of the wire body 32, and improves the tensile strength of the draw wire 3. In addition, spot welding has higher production efficiency. In some other embodiments, if the welding process meets the requirements, a continuous weld can also be used to weld the wire body 32 and the adapter pipe 33 together. In some other embodiments, in addition to welding, the adapter pipe 33 and the draw wire 3 can also be fixed by crimping, riveting, or adhesive bonding. In some other embodiments, the adapter pipe 33 can be either a round tube or a flat tube.

[0072] To further reduce the impact of welding on line 32, in some embodiments, please refer to Figure 5 The length of the adapter pipe 33 is L, and the distance between any solder point 34 and the end face of the adapter pipe 33 is greater than or equal to L / 5. This spacing between the solder point 34 and the end face of the adapter pipe 33 meets certain requirements, preventing the solder point 34 from being too close to the end face of the adapter pipe 33 and damaging the pull wire 3. Of course, in some other embodiments, depending on actual needs and welding parameters, the distance between the solder point 34 and the end face of the adapter pipe 33 can also be less than L / 5.

[0073] Furthermore, in one embodiment, please refer to Figure 5 The spacing between any two adjacent solder joints 34 is greater than or equal to L / 3. Based on the length of the adapter pipe 33, this arrangement of solder joints 34 results in a more uniform distribution, avoiding both excessive density and sparseness. Of course, in some other embodiments, the spacing between two adjacent solder joints 34 can be less than L / 3 as needed. In one embodiment, the diameter of the solder joint 34 is greater than or equal to the outer diameter of the adapter pipe 33, so that the solder joint 34 can cover the adapter pipe 33 radially, improving welding strength. In some other embodiments, the diameter of the solder joint 34 can be less than the outer diameter of the adapter pipe 33.

[0074] Specifically, in one embodiment, the anti-detachment block 4 and the pull wire 3 are fixed by laser welding. For details, please refer to... Figure 10 The length of the welding groove 41 and the dimensions of the anti-detachment block 4 in the extension direction of the pull wire 3 are L1 and L2, respectively, where L1≥L2 / 3. This ensures the length of the side wall weld 51 and improves the welding strength.

[0075] Specifically, in one embodiment, when the anti-detachment block 4 is welded to the pull wire 3, the overlapping area of ​​the weld is not less than 1 / 3 and not more than 1 / 2 of the weld area, which can improve the welding strength. In some other embodiments, the overlapping area can be less than 1 / 3 of the weld area, or there can be no overlapping weld, with a certain gap between adjacent welds. It should be noted that, depending on the welding requirements, the welds 34 and 35 of the anti-detachment block 4 and the pull wire 3 can be the same or different in size.

[0076] In one embodiment, please refer to Figure 13 and Figure 14 The pull-wire structure includes a pull-wire 3 and an anti-dislodgement block 4. The pull-wire 3 is used to be introduced into the tube body 1 of the medical catheter, and the pull-wire 3 has a distal end 31. The anti-dislodgement block 4 is fixed to the distal end 31 of the pull-wire and has a blocking support surface 44. The blocking support surface 44 is used to block the tube body 1 in the extension direction of the pull-wire 3 to limit the pull-wire 3 from dislodging from the tube body 1.

[0077] The anti-detachment block 4 has a welding hole 45, which has a through-hole 42 for the pull wire 3 to pass through in the extension direction of the pull wire 3. The sidewall of the welding hole 45 includes a welding portion 46, at least a portion of which extends in the same direction as the extension direction of the welding hole 45. The welding portion 46 is used for welding outside the welding hole 45 to weld the sidewall of the welding hole 45 to the distal end 31 of the pull wire. The weld formed after welding the welding portion 46 to the distal end 31 of the pull wire extends along the extension direction of the welding hole. It should be noted that the anti-detachment block 4 and the pull wire 3 are laser welded. Since laser welding has requirements on material thickness, the wall thickness of the welding portion 46 should meet the process requirements of laser welding.

[0078] In this embodiment, the pull wire 3 can be the pull wire 3 described in any of the above embodiments, and the anti-detachment block 4 can also be the anti-detachment block 4 described in any of the above embodiments, which will not be described again.

[0079] In some other embodiments, the welding hole 45 may also be a blind hole, with the bottom of the welding hole 45 opposite to the through port 42.

[0080] In some embodiments, due to the small diameter of the draw wire 3, laser welding is used for the welding involved in the above embodiments. Of course, other welding methods besides laser welding can also be used when conditions permit or welding requirements are met, such as electron beam welding, resistance welding, ultrasonic welding, etc.

[0081] An embodiment of a pull-wire structure for a medical catheter, wherein the pull-wire structure of the medical catheter is the pull-wire structure described in any of the above specific embodiments, and will not be repeated.

[0082] The above examples illustrate the present invention only to aid in understanding it and are not intended to limit the scope of the invention. Those skilled in the art can make various simple deductions, modifications, or substitutions based on the principles of this invention.

Claims

1. A medical catheter, characterized in that, The device includes a tube body and a pull-wire structure. The tube body includes a distal bending section, and the pull-wire structure is used to bend the distal bending section. The pull-wire structure includes a pull wire and an anti-dislodgement block. The pull wire is used to be introduced into the tube body of a medical catheter, and the pull wire has a distal end. The anti-detachment block has a welding groove, and the distal end of the pull wire is inserted into the welding groove and welded to the side wall of the welding groove to form a side wall weld; the anti-detachment block is installed on the pipe body, and the anti-detachment block has a blocking support surface, which is used to block the pipe body in the extension direction of the pull wire to limit the pull wire from coming out of the pipe body; The welding groove has a through-hole and a side opening. The through-hole allows the pull wire to pass through in the direction of the pull wire's extension. The side opening exposes the position where the distal end of the pull wire is welded to the side wall of the welding groove before welding. The tube body has a pull wire through hole and an anti-detachment block mounting groove. The pull wire passes through the pull wire through hole, and the anti-detachment block mounting groove is in communication with the pull wire through hole. The anti-detachment block mounting groove is used to install the anti-detachment block from the outside of the tube body.

2. The medical catheter as described in claim 1, characterized in that, The welding groove has a bottom wall opposite to the through-hole. The bottom wall is welded to the far end of the pull wire to form a bottom wall weld. The bottom wall weld intersects with the side wall weld.

3. The medical catheter as described in claim 2, characterized in that, There are two sidewall welds, and the two sidewall welds are respectively connected to the two ends of the bottom wall weld, so that the two sidewall welds and the bottom wall weld are arranged in a U-shape.

4. The medical catheter as described in claim 1, characterized in that, A portion of the distal end of the pull wire extends out of the welding groove through the side opening.

5. The medical catheter as described in claim 1, characterized in that, The extension direction of the sidewall weld is consistent with the extension direction of the pull wire.

6. A medical catheter, characterized in that, The device includes a tube body and a pull-wire structure. The tube body includes a distal bending section, and the pull-wire structure is used to bend the distal bending section. The pull-wire structure includes a pull wire and an anti-dislodgement block. The pull wire is used to be inserted into the tube body of a medical catheter and has a distal end. The anti-dislodgement block is fixed to the distal end of the pull wire and is mounted on the tube body. The anti-dislodgement block has a blocking support surface, which is used to block the tube body in the extension direction of the pull wire to prevent the pull wire from dislodging from the tube body. The anti-detachment block has a welding hole, which has an opening for the pull wire to pass through in the extension direction of the pull wire. The sidewall of the welding hole includes a welding portion, at least a portion of which extends in the same direction as the extension direction of the welding hole. The welding portion is used to weld the sidewall of the welding hole to the distal end of the pull wire during welding. The tube body has a pull wire through hole and an anti-detachment block mounting groove. The pull wire passes through the pull wire through hole, and the anti-detachment block mounting groove is in communication with the pull wire through hole. The anti-detachment block mounting groove is used to install the anti-detachment block from the outside of the tube body.

7. The medical catheter as described in any one of claims 1-6, characterized in that, The anti-detachment block is fixed to the pull wire by laser welding.

8. The medical catheter as described in claim 7, characterized in that, The overlap area between the anti-detachment block and the adjacent weld point at the wire welding point is not less than 1 / 3 and not greater than 1 / 2 of the weld point area.

9. The medical catheter as described in any one of claims 1-6, characterized in that, The pull cable includes a cable body and an adapter tube. The adapter tube is located at the distal end of the pull cable. The cable body has a distal end, which is inserted into the adapter tube and fixed thereto. The pull cable is welded to the anti-detachment block through the adapter tube.

10. The medical catheter as described in claim 9, characterized in that, The distal end of the line body is welded to the adapter by at least two weld points spaced apart in the extension direction of the adapter.

11. The medical catheter as described in claim 10, characterized in that, The length of the adapter pipe is L, and the distance between any of the solder joints and the end face of the adapter pipe is greater than or equal to L / 5.

12. The medical catheter as described in any one of claims 1-6, characterized in that, The mounting groove for the anti-detachment block is filled with a filling medium that fixes the anti-detachment block, and the anti-detachment block is located in the filling medium.

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