CN111375120A

CN111375120A - Adjustable bent catheter

Info

Publication number: CN111375120A
Application number: CN201811653891.5A
Authority: CN
Inventors: 张庭超; 蒋权杰; 黄桥
Original assignee: Hangzhou Weiqiang Medical Technology Co Ltd
Current assignee: Hangzhou Endonom Medtech Co Ltd
Priority date: 2018-12-29
Filing date: 2018-12-29
Publication date: 2020-07-07

Abstract

The invention provides an adjustable bending catheter, which comprises a catheter body and a traction piece, wherein the far end of the catheter body is provided with an adjustable bending section; the traction piece comprises a traction wire, a wire penetrating pipe, a protective sleeve and a crimping pipe, wherein the far end of the traction wire is connected with the adjustable bending section, the near end of the traction wire is wrapped and fixed in the crimping pipe, and the rest parts of the traction wire are sequentially and movably arranged in the wire penetrating pipe and the protective sleeve from far to near; the near end of the threading tube and the far end of the protective sleeve are relatively fixed, no gap exists between the near end of the threading tube and the far end of the protective sleeve in the axial direction of the threading tube and the far end of the protective sleeve, and the far end of the crimping tube movably penetrates through the protective sleeve; the crimping pipe moves in the protective sleeve to drive the traction wire to move in the protective sleeve and the wire penetrating pipe, so that the adjustable bending section is bent or returns to be straight. The inner cavity of the protective sleeve limits the bending deformation degree of the traction wire, so that the traction wire can be prevented from being seriously bent or broken near the near end of the wire feeding pipe, and the smooth realization of the bending adjusting function of the adjustable bent catheter is ensured.

Description

Adjustable bent catheter

Technical Field

The invention relates to the technical field of medical instruments, in particular to an adjustable bending catheter.

Background

The interventional operation has less damage to human body and short operation time, and the catheter is used as auxiliary instrument for interventional operation and is used mainly in establishing the passage between blood vessel and outside to convey diagnosis and/or treatment instrument.

In order to adapt to individual differences of human physiological anatomical structures, the adjustable bending catheter is widely applied. The adjustable bending catheter is characterized in that an adjustable bending section is arranged at the far end of a catheter body of the catheter, a handle of the catheter is controlled to drive a traction wire connected with the adjustable bending section to move axially, so that the far end of the catheter body is repeatedly bent at different angles until the bending angle accords with the specific physiological structural characteristics of a human lumen, then the bending angle is locked, the far end of the catheter body is aligned to the entrance of a target lumen (such as a certain blood vessel), and then diagnostic and/or therapeutic instruments are conveyed into the target lumen through the catheter body.

Referring to fig. 1, the conventional bendable catheter usually has a pull wire disposed inside a threading tube 320, the threading tube 320 is mostly embedded in the wall of the tubular body 1000, the proximal end of the pull wire 310 extends out of the threading tube 320 and is connected to a slide block 2210 in a handle, and the movement of the slide block 2210 drives the pull wire 310 to move axially, thereby bending the bendable section at the distal end of the tubular body 1000. Since the pull wire 310 is generally very thin, when the pull wire 310 is pushed by the slider 2210 toward the distal end of the catheter body 1000, if the pushing force is large and the pushing speed is too fast, the progress of the pull wire 310 entering the threading catheter 320 will lag behind the progress of the slider 2210, so that the pull wire 310 is easily severely bent or even broken near the proximal port of the threading catheter 320 (e.g., position a in fig. 1), which may hinder the bending function of the bendable catheter.

Disclosure of Invention

The invention aims to provide an adjustable bent catheter, which can prevent a traction wire from being seriously bent or broken near the proximal end of a wire feeding tube and ensure the smooth realization of the bending function of the adjustable bent catheter.

In order to achieve the above object, the present invention provides an adjustable bending catheter, which includes a catheter body and a traction member, wherein the distal end of the catheter body is provided with an adjustable bending section; the traction piece comprises a traction wire, a wire penetrating pipe, a protective sleeve and a crimping pipe, the far end of the traction wire is connected with the adjustable bending section, the near end of the traction wire is wrapped and fixed in the crimping pipe, and the rest parts of the traction wire are sequentially and movably arranged in the wire penetrating pipe and the protective sleeve from far to near; the near end of the threading tube and the far end of the protective sleeve are relatively fixed, no gap exists between the near end of the threading tube and the far end of the protective sleeve in the axial direction of the near end of the threading tube and the far end of the protective sleeve, the far end of the crimping tube movably penetrates through the protective sleeve, and the crimping tube moves in the protective sleeve to drive the traction wire to move in the protective sleeve and the threading tube, so that the adjustable bending section is bent or recovered to be straight.

The near end of the threading tube is butted with the far end of the protective sleeve or the near end of the threading tube penetrates into the far end of the protective sleeve.

The protective sleeve comprises an inclined section, a transition section and a straight section which are sequentially connected, the transition section is smoothly connected with the inclined section and the straight section, the inclined section is relatively fixed with the near end of the wire threading tube, and the near end of the crimping tube is movably arranged in the straight section in a penetrating mode.

The inner diameter of the protective sleeve is 0.1-0.3 mm larger than the outer diameter of the crimping pipe, and the inner diameter of the protective sleeve is 0.3-0.6 mm larger than the diameter of the traction wire.

The length of the protective sleeve is larger than the distance which the traction wire needs to move when the adjustable bending section is switched between the straight angle and the maximum bending angle.

The proximal end of the threading tube extends out of the tube body, and the rest part of the threading tube is embedded in the tube wall of the tube body.

The bending adjusting handle is connected to the near end of the tube body and connected with the near end of the crimping tube; the bending adjusting handle controls the crimping pipe to move in the protective sleeve.

The bending adjusting handle comprises a fixed base body, a driving mechanism and a driving control mechanism; the near end of the tube body penetrates through and is fixed in the fixed base body, the protective sleeve is fixed relative to the fixed base body, the crimping tube is connected with the driving mechanism, the driving control mechanism is connected with the driving mechanism and controls the driving mechanism to move relative to the fixed base body, and the driving mechanism moves to drive the crimping tube to move in the protective sleeve.

The driving mechanism comprises a sliding block and a fixed block fixed with the sliding block, the crimping pipe is fixed with the fixed block, a thread groove is formed in the surface of the sliding block, the driving control mechanism comprises a rotary cylinder, threads meshed with the thread groove are arranged in the rotary cylinder, and the rotary cylinder drives the sliding block to move relative to the fixed base body.

Wherein, the length of the protective sleeve is longer than the maximum stroke of the slide block.

The fixing base body is provided with an axial groove which is axially arranged along the fixing base body; the sliding block is movably arranged in the axial groove, and the rotary cylinder is rotated to drive the sliding block to move along the axial groove.

The near end of the tube body is embedded in the fixing base body, the central axis of the tube body coincides with the central axis of the fixing base body, an inclined groove is formed in the fixing base body, one end of the inclined groove extends to the tube body, the other end of the inclined groove extends to the axial groove, and the protection sleeve is fixed in the inclined groove.

The adjustable bending guide pipe provided by the invention is characterized in that the crimping pipe is arranged to wrap and fix the traction wire, the protective sleeve is arranged between the wire penetrating pipe and the crimping pipe, the near end of the wire penetrating pipe and the far end of the protective sleeve are seamless in the axial directions of the wire penetrating pipe and the crimping pipe, and the far end of the crimping pipe is movably arranged in the protective sleeve in a penetrating manner, so that the part of the traction wire between the wire penetrating pipe and the crimping pipe is arranged in the protective sleeve in a penetrating manner. In the process that the bending-adjustable section of the pipe body is bent or straightened, the crimping pipe drives the traction wire to move in the protective sleeve and the wire penetrating pipe, so that the part of the traction wire between the wire penetrating pipe and the crimping pipe is always positioned in the protective sleeve, the inner cavity of the protective sleeve limits the bending deformation degree of the traction wire, the traction wire can be prevented from being seriously bent or broken near the near end of the wire penetrating pipe, and the smooth realization of the bending-adjustable function of the bending-adjustable pipe is ensured.

Drawings

To more clearly illustrate the structural features and effects of the present invention, a detailed description is given below with reference to the accompanying drawings and specific embodiments.

Fig. 1 is a schematic view of a conventional bendable catheter in which a traction wire is severely bent;

FIG. 2 is a schematic perspective view of an adjustable bend catheter according to an embodiment of the present invention;

FIG. 3 is an exploded perspective view of an adjustable bend conduit according to an embodiment of the invention;

FIG. 4 is a schematic cross-sectional view of an adjustable bend conduit according to an embodiment of the invention;

FIG. 5 is an enlarged partial schematic view at II of FIG. 4;

FIG. 6 is a schematic view of the structure of the pulling member and the distal end of the catheter body in an embodiment of the invention;

FIG. 7 is a schematic view of the position of the pull wire, the threading tube, the protective sheath and the crimping tube at the maximum bending angle of the adjustable bending section of the adjustable bending catheter according to the embodiment of the invention;

FIG. 8 is a schematic view of the position of the pull wire, the threading tube, the protective sheath and the crimping tube when the adjustable bending section of the adjustable bending catheter of the embodiment of the invention returns to the flat state;

FIG. 9 is a schematic view of the structure of the pulling member and the proximal end of the catheter body in an embodiment of the invention;

fig. 10 is a schematic diagram of a protective sheath for an adjustable bending catheter, in accordance with an embodiment of the present invention.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. The drawings are for illustration purposes only and are merely schematic representations, not intended to limit the present invention.

To more clearly describe the structure of the steerable catheter, the terms "proximal" and "distal" are defined herein as terms commonly used in the interventional medical field. Specifically, "distal" refers to the end of the surgical procedure that is distal from the operator, and "proximal" refers to the end of the surgical procedure that is proximal to the operator.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Referring to fig. 2 to 5, the present invention provides an adjustable bending catheter 100. The adjustable bending catheter 100 comprises a catheter body 10, a bending handle 20 and a traction member 30. The bending handle 20 is connected to the proximal end of the tube 10. The far end of the pipe body 10 is provided with an adjustable bending section 11, and the bending angle of the adjustable bending section 11 can be adjusted according to actual needs. In this embodiment, the pipe body 10 is provided with an adjustable bending section 11. It will be appreciated that in other embodiments of the present application, the adjustable bending sections 11 may be provided on the tubular body 10.

Referring to fig. 2 and 6, the tube body 10 includes an inner film 10a, a reinforcing tube 10b sleeved on the inner film 10a, and an outer tube 10c sleeved on the reinforcing tube 10 b. In this embodiment, the inner membrane 10a is a flexible tube made of flexible material such as PTFE, and is easy to bend; the reinforcing pipe 10b is a metal woven mesh structure, has certain rigidity and can be bent in the axial direction, so that the pipe 10 is supported, the pipe 10 is prevented from being twisted and deformed in the radial direction, and the bending of the adjustable bending section 11 of the pipe 10 is not influenced; the outer tube 10c is made of a material having a certain hardness, such as PEBAX, to protect the pipe body 10. Moreover, the hardness of the outer tube 10c corresponding to the adjustable bending section 11 is less than that of other parts of the outer tube 10c, so that the influence on the bending of the adjustable bending section 11 is avoided while the protection of the tube body 10 is realized. Specifically, in the present embodiment, the hardness of the PEBAX material used for the portion of the outer tube 10c corresponding to the adjustable bending section 11 is lower than that of the other portion of the outer tube 10 c. Further, in this embodiment, the inner tube 10a, the reinforcing tube 10b and the outer tube 10c are formed by heat-melting and composite molding, so as to form at least one delivery lumen extending completely from the proximal end to the distal end. It is understood that in other embodiments of the present invention, the tubular body 10 may only include the inner tube 10a and/or the outer tube 10c, and the inner tube 10a, the reinforcing tube 10b and the outer tube 10c may be made of other materials than the present embodiment.

Further, in some embodiments of the present application, the end of the tubular body 10 is an arc-shaped end with a smooth surface, i.e. a Tip head, and a radiopaque developing ring (not shown) such as a tantalum ring is disposed near the Tip head, so that whether the distal end of the tubular body 10 reaches a designated position can be accurately known under a developing device.

Referring to fig. 3 to 9, the pulling member 30 includes a pulling wire 31, a wire feeding tube 32, a protecting sleeve 33 and a pressing tube 34. The far end of the traction wire 31 is connected with the adjustable bending section 11, the near end is wrapped and fixed in the crimping pipe 34, and the rest parts are movably arranged in the wire passing pipe 32 and the protective sleeve 33 from far to near in sequence.

The traction wire 31 is used for drawing the adjustable bending section 11 to bend or restore to be straight, and has certain strength. In this embodiment, the drawing wire 31 is a single structure, and may also be a multi-strand structure. The cross-sectional shape of the traction wire 31 may be various shapes such as a circle, and is not particularly limited. The radial section of the traction wire 31 should be as small as possible on the basis of a certain strength to achieve the traction function, so the diameter of the traction wire 31 is preferably in the range of 0.05 mm to 0.25 mm. The traction wire 31 may be made of a metal material, such as stainless steel, tungsten alloy, cobalt-chromium alloy, or nickel-titanium alloy, or may be made of a polymer having a certain strength, and the material thereof is not particularly limited. In this embodiment, the pull wire 31 is preferably a stainless steel wire having a diameter of 0.25 mm.

The pull wire 31 with the one end that adjustable curved section 11 is connected is equipped with anchor ring 35, anchor ring 35 is the cyclic annular piece, and the cover is located on adjustable curved section 11, promptly the distal end of pull wire 31 passes through anchor ring 35 with adjustable curved section 11 is connected. In this embodiment, the anchoring ring 35 is sleeved on the inner membrane 10a at a position corresponding to the adjustable bending section 11. The contact area of the pulling element 30 with the adjustable bending section 11 of the pipe body 10 is increased by the anchoring ring 35, so that the bending of the adjustable bending section 11 can be better pulled. The anchoring ring 35 may be made of a metal material or a polymer material, and in this embodiment, the anchoring ring 35 is made of a metal, such as SUS304 stainless steel. The attachment of the traction wire 31 to the anchoring ring 35 may be by means including, but not limited to, adhesive, welding, heat staking, knotting, and the like.

The drawing wire 31 is mostly movably arranged in the threading tube 32, so that the drawing direction of the drawing wire 31 is limited by the threading tube 32, and the drawing wire 31 is protected by the threading tube 32. Most of the threading tube 32 is embedded in the tube wall of the tube body 10 and extends along the axial direction of the tube body 10, so that when the traction wire 31 threaded in the threading tube 32 moves in the threading tube 32, the traction wire 31 moves along the axial direction of the tube body 10. The proximal end of the threading tube 32 extends from the wall of the tubular body 10 at a specific angle so that the pull wire 31 threaded therein can pass out of the threading tube 32 at a specific angle. In this embodiment, the threading tube 32 is embedded between the inner membrane 10a and the reinforcing tube 10 b. By embedding the threading tube 32 in the tube body 10, the diameter of the tube body 10 can be reduced to ensure that the tube body 10 is easily moved in a target lumen of a human body. The threading tube 32 may be made of various materials suitable for medical devices, such as metal or polymer. There is a suitable clearance between the inner diameter of the threading tube 32 and the diameter of the pull wire 31 to allow for smooth movement of the pull wire 31 within the threading tube 32. In this embodiment, the difference between the inner diameter of the threading tube 32 and the diameter of the pull wire 31 is greater than 0 and less than 0.1 mm.

The proximal end of the crimping pipe 34 is connected with the bending adjusting handle 20, so that the proximal end of the pull wire 31 is connected with the bending adjusting handle 20 through the crimping pipe 34, the risk that the pull wire 31 is easily broken when being directly connected with the bending adjusting handle 20 due to the fact that the pull wire 31 is thin is avoided, and the connection strength between the pull wire 31 and the bending adjusting handle 20 is improved. Moreover, the distal end of the crimping tube 34 is movably inserted into the protective sleeve 33, that is, when the bending adjusting handle 20 drives the crimping tube 34 and the traction wire 31 to move to adjust the bending state of the bending adjustable section 11, the distal end of the crimping tube 34 is always located in the protective sleeve 33. Notably, the proximal end of the threading tube 32 is fixed opposite the distal end of the protective sheath 33, and the proximal end of the threading tube 32 and the distal end of the protective sheath 33 are free of gaps in the axial direction therebetween. The term "relatively fixed" refers to that the proximal end of the threading tube 32 and the distal end of the protective sheath 33 are fixed by welding, bonding, or the like, or fixed by a fixing member, and the threading tube 32 and the protective sheath 33 may also be fixed separately, so as to keep the proximal end of the threading tube 32 and the distal end of the protective sheath 33 from moving relatively.

In this embodiment, the proximal ends of the threading tubes 32 are covered by the distal ends of the protective sheath 33 and fixed to each other. It will be appreciated that the proximal end of the threading tube 32 may also be abutted against the distal end of the protective sheath 33, i.e., the distal end of the protective sheath 33 abuts against and is secured to the proximal end of the threading tube 31; alternatively, the protective sheath 33 may be arranged to extend from the proximal end of the threading tube 32, i.e. the protective sheath 33 is integral with the threading tube 32.

Because the far end of the crimping pipe 34 is movably arranged in the protective sleeve 33, the inner diameter of the protective sleeve 33 can not prevent the crimping pipe from smoothly moving in the protective sleeve 33, and a small gap is required between the protective sleeve 33 and the traction wire 31, so that the radial moving space of the traction wire 31 is reduced, the bending degree of the traction wire 31 is limited, and the traction wire is prevented from being excessively bent. Preferably, the inner diameter of the protective sleeve 33 is 0.1mm to 0.3mm larger than the outer diameter of the crimping pipe 34, and the inner diameter of the protective sleeve 33 is 0.3mm to 0.6mm larger than the diameter of the traction wire 31.

Referring to fig. 7 and 8, the length of the protective sleeve 33 is greater than the moving length of the traction wire 31 during the bending process of the adjustable bending section 11 on the tube body 10 from the initial flat state to the maximum bending angle, so that the proximal end of the crimping tube 34 is always located in the protective sleeve 33, and thus the section of the traction wire 31 exposed between the threading tube 32 and the crimping tube 34 is always wrapped by the protective sleeve 33, the inner cavity of the protective sleeve 33 always limits the bending deformation degree of the section of the traction wire 31, and once the section of the traction wire 31 contacts the inner cavity of the protective sleeve 33 due to bending, the inner cavity of the protective sleeve 33 immediately generates a pushing force on the bent traction wire 31 to force the traction wire 31 to enter the threading tube 32, so that the section of the traction wire 31 is restored to a relatively flat state, and thus the risk of the traction wire 31 being severely bent or broken near the proximal end of the threading tube 32 can be reduced or even avoided, the bending adjustable section 11 of the pipe body 10 can be smoothly bent or straightened. In this embodiment, the cross-sectional shape of the protective sheath 33 is identical to the cross-sectional shape of the traction wire 31, and the protective sheath 33 is preferably made of metal, such as stainless steel, red copper, aluminum alloy, or the like. It is understood that in other embodiments, the protective sleeve 33 may be made of a polymer having a certain strength. Preferably, in this embodiment, the protection casing 33 is a stainless steel pipe with an inner diameter of 0.7mm and an outer diameter of 1.0 mm.

Further, referring to fig. 9 and 10, in the present embodiment, the protecting sleeve 33 includes a straight section 331 axially parallel to the tube body 10, an inclined section 332 having the same inclination angle as that of the portion of the threading tube 31 penetrating through the wall of the tube body 10, and a transition section 333 connected between the straight section 331 and the inclined section 332. The transition section 333 is arc-shaped and smoothly connects the inclined section 332 and the straight section 331, so as to ensure that the traction wire 31 smoothly moves in the protective sleeve 33. The inclined section 332 and the proximal end of the part of the threading tube 31 penetrating through the tube wall of the tube body 10 are relatively fixed and have the same inclination angle, so as to avoid blocking the movement of the traction wire 31 in the protective sleeve 33; the crimping tube 34 is movably inserted into the straight section 331, and the length of the straight section 331 is longer than the moving length of the pulling wire 31 in the process of bending the adjustable bending section 11 from the initial straight state to the maximum bending angle, so that the proximal end of the crimping tube 34 is always located in the protective sleeve 33.

Referring back to fig. 2 to 5, the bending adjustment handle 20 includes a fixing base 21, a driving mechanism 22 and a driving control mechanism 23. The proximal end of the tube 10 is fixed to the fixing base 21, the protecting sleeve 33 is preferably fixed to the fixing base 21, the crimping tube 34 is connected to the driving mechanism 22, the driving control mechanism 23 is connected to the driving mechanism 22 to control the driving mechanism 22 to move relative to the fixing base 21, and the driving mechanism 22 moves to drive the crimping tube 34 to move in the protecting sleeve 33, so as to drive the traction wire 31 to move to adjust the bending state of the adjustable bending section 11. The fixing base 21 is substantially cylindrical, and the pipe 10 is inserted into the center of the fixing base 21 and fixed to the fixing base 21. In this embodiment, the fixing base 21 is divided into a first portion 211 and a second portion 212 that are fastened to each other, corresponding grooves are disposed on the first portion 211 and the second portion 212, and a central hole for passing through the pipe 10 is formed by the grooves on the first portion 211 and the second portion 212, so that the pipe 10 is conveniently passed through the fixing base 21 and fixed to the fixing base 21. Further, the fixing base 21 is provided with an axial groove 213 provided along the axial direction of the fixing base 21, and an inclined groove 214 extending from the pipe 10 to the axial groove 213. Specifically, the inclined groove 214 comprises an inclined section and a straight section connected with the inclined section, one end of the inclined section is connected with the straight section, and the other end of the inclined section extends to the pipe body 10, so that the wire penetrating pipe 32 extending from the pipe wall of the pipe body 10 extends into the inclined section; the straight section has one end connected to the inclined section and the other end extending to the axial slot 213. In this embodiment, the inclined section has the same inclination angle as the inclined section 332 of the protective sheath 33, the inclined section 332 and the portion of the threading tube 32 extending out of the tube wall of the tube body 10 are preferably fixed in the inclined section by gluing, and the straight section 331 of the protective sheath 33 is preferably fixed in the straight section by gluing, so that the protective sheath 33 can be stably fixed in the bendable catheter 100.

The driving mechanism 22 includes a slider 221 and a fixing block 222 fixed to the slider 221. In this embodiment, the sliding block 221 is provided with a groove, and the fixing block 222 is embedded and fixed in the groove. The proximal end of the crimp tube 34 is secured to the anchor block 222. In this embodiment, the crimping tube 34 and the fixing block 222 are preferably fixed by welding. It is understood that in other embodiments of the present application, the crimp tube 34 and the fixing block 222 may be fixed by bonding or the like. The sliding block 221 is movably disposed in the axial groove 213. The surface of the sliding block 221 is provided with a spiral groove 2211. The driving control mechanism 23 includes a rotary cylinder 231, a thread 2311 engaged with the thread groove 2211 is arranged in the rotary cylinder 231, and the rotary cylinder 231 can drive the slide block 221 to move in the axial direction of the fixed base 21 in the axial groove 213 by the engagement of the thread 2311 and the thread groove 2211. In this application, the crimping pipe 34 with the fixed block 222 is fixed, the slider 221 moves in the axial groove 213 and can drive the crimping pipe 34 to move in the protective sleeve 33, and the traction wire 31 fixed to the crimping pipe 34 pulls the adjustable bending section 11 to bend or return to straight. Further, the driving control mechanism 23 further includes a rotary grip 232 provided on the outer peripheral surface of the proximal end of the rotary cylinder 231, and an outer surface of the rotary grip 232 is provided with an anti-slip structure, so that the rotary cylinder 231 can be more easily rotated by rotating the rotary grip 232.

Further, a luer connector 40 is fixed at the proximal end of the rotary cylinder 231, and the tube 10 passes through the fixing base 21 and is connected to the luer connector 40, so that the diagnosis and/or treatment instrument can reach the target lumen of the human body through the luer connector 40 and the tube 10 in sequence.

Further, the bend adjustment handle 20 further includes a housing 50, and the structure disposed inside the housing 50 is protected by the housing 50. The fixed base 21 and the driving mechanism 22 are accommodated in the housing 50, the distal end of the rotary cylinder 231 is accommodated in the housing 50 and rotatably connected with the housing 50, and the rotary grip 232 is disposed outside the housing 50 for performing a rotary operation. Specifically, a snap ring 51 is disposed on an inner wall of the proximal end of the housing 50, a snap groove 2312 is annularly disposed on an outer circumferential surface of the rotary cylinder 231, and the snap ring 51 is clamped in the snap groove 2312 to realize the rotary connection between the rotary cylinder 231 and the housing 50. Further, in the present embodiment, the housing 50 includes two parts detachably connected to each other, so that the fixing base 21, the driving mechanism 22, and the like can be more easily fixed in the housing 50.

Further, in the present application, the bend adjustment handle 20 further includes an end cap 60 fixed to the distal end of the housing 50, and the tube 10 penetrates into the fixing base 21 through the end cap 60.

The adjustable bending catheter 100 of the present invention is configured such that the crimping tube 34 is disposed to surround and fix the traction wire 31, the protective sleeve 33 is disposed between the threading tube 32 and the crimping tube 34, and the proximal end of the threading tube 32 and the distal end of the protective sleeve 33 have no gap therebetween in the axial direction, and the distal end of the crimping tube 34 is movably inserted into the protective sleeve 33, so that the portion of the traction wire 31 located between the threading tube 32 and the crimping tube 34 is inserted into the protective sleeve 33. In the process that the adjustable bending section 11 of the tube body 10 is bent or restored to be straight, the crimping tube 34 drives the traction wire 31 to move in the protective sleeve 33 and the threading tube 32, so that the part of the traction wire 31 located between the threading tube 32 and the crimping tube 34 is always located in the protective sleeve 33, the inner cavity of the protective sleeve 33 limits the degree of bending deformation of the traction wire 31, the traction wire 31 can be prevented from being seriously bent or broken near the proximal end of the threading tube 32, and the smooth realization of the bending adjusting function of the adjustable bending guide tube 100 is ensured.

The foregoing is directed to the preferred embodiment of the present invention, and it is understood that various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention.

Claims

1. The adjustable bending catheter is characterized by comprising a catheter body and a traction piece, wherein an adjustable bending section is arranged at the far end of the catheter body; the traction piece comprises a traction wire, a wire penetrating pipe, a protective sleeve and a crimping pipe, the far end of the traction wire is connected with the adjustable bending section, the near end of the traction wire is wrapped and fixed in the crimping pipe, and the rest parts of the traction wire are sequentially and movably arranged in the wire penetrating pipe and the protective sleeve from far to near; the near end of the threading tube and the far end of the protective sleeve are relatively fixed, no gap exists between the near end of the threading tube and the far end of the protective sleeve in the axial direction of the threading tube and the far end of the protective sleeve, and the far end of the crimping tube is movably arranged in the protective sleeve in a penetrating mode; the crimping pipe moves in the protective sleeve to drive the traction wire to move in the protective sleeve and the wire penetrating pipe, so that the adjustable bending section is bent or returns to be straight.

2. The adjustable bend catheter of claim 1, wherein the proximal end of the threading tube abuts the distal end of the protective sheath or the proximal end of the threading tube passes into the distal end of the protective sheath.

3. The adjustable bending catheter according to claim 1 or 2, wherein the protecting sheath comprises an inclined section, a transition section and a straight section which are connected in sequence, the transition section is smoothly connected with the inclined section and the straight section, the inclined section is fixed relative to the proximal end of the threading catheter, and the proximal end of the crimping catheter is movably arranged in the straight section.

4. The adjustable bend catheter of claim 1, wherein the inner diameter of the protective sheath is 0.1mm to 0.3mm larger than the outer diameter of the crimping tube, and the inner diameter of the protective sheath is 0.3mm to 0.6mm larger than the diameter of the pull wire.

5. The adjustable bend catheter of claim 1, wherein the length of the protective sheath is greater than the distance the pull wire must travel when the adjustable bend section is switched between straight and maximum bend angles.

6. The adjustable bend catheter of claim 1, wherein the proximal end of the threading tube extends out of the tubular body and the remaining portion is embedded in the wall of the tubular body.

7. The adjustable bend catheter of claim 1, further comprising a bend adjustment handle connected to the proximal end of the catheter body and to the proximal end of the crimp tube; the bending adjusting handle controls the crimping pipe to move in the protective sleeve.

8. The adjustable bend catheter of claim 7, wherein said bend adjustment handle comprises a stationary base, a drive mechanism, and a drive control mechanism; the near end of the tube body penetrates through and is fixed in the fixed base body, the protective sleeve is fixed relative to the fixed base body, the crimping tube is connected with the driving mechanism, the driving control mechanism is connected with the driving mechanism and controls the driving mechanism to move relative to the fixed base body, and the driving mechanism moves to drive the crimping tube to move in the protective sleeve.

9. The adjustable bending catheter according to claim 8, wherein the driving mechanism comprises a slider and a fixed block fixed to the slider, the crimping tube is fixed to the fixed block, a groove is formed on a surface of the slider, the driving control mechanism comprises a rotary cylinder, a thread engaged with the groove is formed in the rotary cylinder, and the rotary cylinder is rotated to drive the slider to move relative to the fixed base.

10. The adjustable bend catheter of claim 9, wherein the length of the protective sheath is greater than the maximum travel of the slider.

11. The adjustable bend catheter according to claim 9, wherein the fixing base is provided with an axial groove disposed axially along the fixing base; the sliding block is movably arranged in the axial groove, and the rotary cylinder is rotated to drive the sliding block to move along the axial groove.

12. The adjustable bend catheter of claim 11, wherein said proximal end of said tube is embedded in said stationary base and said central axis of said tube is coincident with said central axis of said stationary base, said stationary base having an angled groove extending into said tube at one end and into said axial groove at the other end, said protective tubing being secured in said angled groove.

13. The adjustable bend catheter of claim 9, wherein said bend adjustment handle further comprises a housing, said drive mechanism being received in said housing, and a distal end of said turn cylinder being received in said housing and rotatably coupled thereto.