CN118266839A

CN118266839A - Insertion device and endoscope

Info

Publication number: CN118266839A
Application number: CN202410243943.0A
Authority: CN
Inventors: 许春辉; 李亚东; 王燕涛
Original assignee: Shanghai Aohua Endoscopy Co ltd
Current assignee: Shanghai Aohua Endoscopy Co ltd
Priority date: 2024-03-04
Filing date: 2024-03-04
Publication date: 2024-07-02

Abstract

The invention provides an insertion device and an endoscope. The insertion part of the insertion device comprises a first bending part, a second bending part and a flexible pipe part, wherein the first bending part, the second bending part and the flexible pipe part are connected towards the base end side along the front end side, the first bending part actively bends by traction of wires, the second bending part passively bends by external force, the second bending part is a hollow pipe formed by a plurality of bending joints, and the plurality of bending joints formed integrally comprise side wall notches and bearing parts; the free ends of the side wall notches are positioned on the same circumference of the side circumferential surface of the hollow tube, and the connecting line between the central points of at least two bearing parts on the same bending joint is approximately coincident with the symmetrical line of the cross section of the hollow tube; the second bending portion is formed so that the rigidity and the radius of curvature at the time of maximum bending are smaller than those of the flexible tube portion and larger than those of the first bending portion. The passive bending portion thus provided can maintain good insertability of the insertion portion while enabling stable endoscope view and accurate maneuvering ability when the endoscope is operated.

Description

Insertion device and endoscope

Technical Field

The invention relates to the technical field of endoscopes, in particular to an insertion device and an endoscope.

Background

Endoscopes are widely used for observation, treatment, etc. in vivo (in a body cavity), or for examination, repair, etc. in industrial machinery. In particular, medical endoscopes are widely used in which an elongated insertion portion is inserted into a body cavity, an examination target site in the body cavity can be observed without cutting, and if necessary, therapeutic treatment can be performed using a treatment instrument.

Regarding the endoscope in this medical field, in a state where the body cavity is sharply bent, resistance between the passive bending portion and the body cavity wall becomes large, and instead, the insertion portion is difficult to insert into the body cavity of the bending portion, and in order to improve the insertion property into the body cavity of the patient, the endoscope disclosed in the related art CN101115432a restricts the radius of curvature by the curvature restricting block, realizes that the radius of curvature of the passive bending portion is larger than the radius of curvature of the bending portion by the stopper, and the stopper manufacturing and assembling are complicated, and the radius of curvature of the passive bending portion and the bending rigidity adjusting range are limited.

Further, the passive bending portion using the curvature restricting block disclosed in the related art CN102858227a reduces the angle difference of bending time in different directions by using the angle of the rotation axis distribution, and although emphasis is given to the rotation axis distribution to avoid the incongruity of the bending operation, the bending rigidity is still achieved by adjusting the bending block, and the number of bending axes and the angle of rotation of adjacent bending axes along the central axis of the passive bending portion are restricted due to the limitations of the length of the passive bending portion and the number of the curvature restricting block structures, etc.

Disclosure of Invention

The invention provides an insertion device and an endoscope, aiming at solving the technical defects that the structure of a passive bending part of an insertion part is complex to assemble, the rigidity adjustability is poor, the bending deformation of the whole passive bending is inconsistent and the like in the prior art.

One possible embodiment of the present invention provides an insertion device having an insertion portion that is inserted from a distal end side into a subject in a longitudinal axis direction, the insertion portion including:

an I-th bending portion provided at a distal end side of the insertion portion and actively bending by pulling the wire;

A second bending portion provided on a base end side of the first bending portion, the second bending portion being passively bent by an external force;

the flexible pipe part and the first bending part are respectively connected with two opposite ends of the second bending part;

the second bending part comprises a hollow pipe formed by a plurality of bending joints, and the hollow pipe is integrally formed;

each bending joint comprises a side wall notch and a bearing part;

the free ends of the side wall notches are positioned on the same circumference of the side circumferential surface of the hollow tube;

The connecting line between the central points of at least two bearing parts on the same bending joint is approximately coincident with the symmetrical line of the cross section of the hollow tube;

The rigidity of the second bending part is smaller than that of the flexible pipe part and larger than that of the first bending part, and the radius of curvature of the maximum bending of the second bending part is smaller than that of the maximum bending of the flexible pipe part and larger than that of the maximum bending of the first bending part.

Optionally, the insertion device further comprises: and a flexible tube which is spirally provided on the outer periphery of the wire and is fixed to one end of the II-th bending portion on the side close to the I-th bending portion.

Alternatively, the bearing parts on two adjacent bending joints in the length axis direction are arranged in a relatively deflected manner. .

Optionally, a plurality of bending joints adjacently disposed along the length axis direction of the hollow tube are formed as one array unit, and a plurality of sidewall notches in each array unit are equally spaced around the circumference of the hollow tube.

Optionally, the side wall notches of the same array unit have equal notch widths, and the notch widths of different array units have a decreasing trend along the direction from the first bending portion to the flexible pipe portion.

Optionally, the predetermined arc lengths of the carrying parts of the same array unit are equal, and the predetermined arc lengths of the carrying parts of different array units have an increasing trend along the direction from the first bending part to the flexible pipe part.

Optionally, the gap width of the sidewall gap at the connecting part of the two ends of the hollow tube in the length axis direction is not smaller than the gap width of any other sidewall gap.

Optionally, the wall thickness of the hollow tube tends to increase in the direction of the I-th bend to the direction of the flexible tube portion.

Optionally, the II bending portion is formed integrally with the fixing portion of the flexible tube.

Optionally, the second bending part further comprises a protective layer covering the periphery of the second bending part, and the protective layer is fixedly connected with two ends of the second bending part.

In another possible implementation of the invention, an endoscope is provided that includes the insertion device of any of the previous implementations.

According to the invention, the plurality of side wall notches and the bearing parts are arranged on the hollow tube, so that the radial elasticity of the passive bending part can be attached to the shape of the intestinal tract or the airway, and friction and stimulation to the intestinal tract or the airway are reduced, so that pain and discomfort of a patient are relieved, the lens at the end part of the endoscope lens cannot be displaced in the length axis direction during bending, and a doctor can obtain a clearer and more stable visual field during operation or examination. And meanwhile, the risks of passive bending failure or hollow pipe fracture and the like caused by sudden displacement or distortion in the length axis direction or stretching deformation in the bending process are prevented.

The bending rigidity of the passive bending part can be accurately regulated in a larger range through the design of the side wall notch and the bearing part, the bending flexibility and the circumferential bending uniformity of the hollow pipe are improved, and the design of the side wall notch and the bearing parts on the integrally formed hollow pipe formed by a plurality of bending joints ensures that the II bending part cannot be deformed in compression or stretching when the mirror is in or out of the mirror when external force is applied; meanwhile, the bearing part and the side wall notch are matched according to bending requirements, so that bending of the passive bending part of the endoscope in all directions is more flexible, the II bending part is not easy to deform when being stretched or compressed in the length axis direction when being subjected to external force, meanwhile, good insertability of the inserting part in a body cavity is kept, a doctor can bend and turn in the operation process conveniently, and bending compliance of the passive bending part in the body cavity is improved.

Drawings

In order to more clearly illustrate the invention or the technical solutions of the prior art, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are embodiments of the invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of an endoscope structure;

FIG. 2 is a schematic view of the structure of the insertion device;

FIG. 3 is a schematic view of a securing structure for a flexible tube;

FIG. 4 is another schematic illustration of a securing structure for a flexible tube;

FIG. 5 is a schematic illustration of a hollow tube force;

FIG. 6 is a schematic view of a hollow tube;

FIG. 7 is a schematic view of a hollow tube;

FIG. 8 is a schematic plan view of the hollow tube of FIG. 7 extending in the longitudinal direction;

FIG. 9 is a schematic view of the structure of section A-A of FIG. 8;

FIG. 10 is a schematic view of the structure of section B-B of FIG. 8;

FIG. 11 is a schematic view of another hollow tube;

FIG. 12 is a schematic plan view of the hollow tube of FIG. 11 extending in the longitudinal direction;

FIG. 13 is a schematic view of the structure of section C-C of FIG. 12;

FIG. 14 is a schematic view of the structure of section D-D of FIG. 12;

FIG. 15 is a schematic cross-sectional view of a gradual change in radius of curvature for maximum bending of a hollow tube;

FIG. 16 is a schematic view showing the gradual change of the radius of curvature at the maximum bend of the insertion portion;

FIG. 17 is a schematic cross-sectional view of a hollow tube with graded stiffness;

FIG. 18 is a schematic illustration of a gradual change in the length of a predetermined arc segment of a hollow tube carrier;

FIG. 19 is a schematic illustration of a gradual change in insert stiffness;

FIG. 20 is a schematic view of another hollow tube;

FIG. 21 is a schematic plan view of the hollow tube of FIG. 20 extending in the longitudinal direction;

FIG. 22 is a schematic view of another hollow tube;

fig. 23 is a schematic view of another insertion device.

Description of the reference numerals

10-Endoscope, 20-insertion part, 30-operation part, 21-I bending part, 22-II bending part, 23-flexible tube part, 211-section wheel, 24-hollow tube, 241-side wall notch, 2411, 2412-free end, 242-bearing part, 25-protection layer, 26-line, 27-flexible tube, 28-fixing part.

Detailed Description

In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the embodiments of the present invention. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In embodiments of the invention, unless expressly specified and limited otherwise, a first feature "up" or "down" on a second feature may be that the first and second features are in direct contact, or that the first and second features are in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

In the description of the present specification, a description referring to the terms "one embodiment," "an example," "a particular example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the embodiments of the invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

Related embodiments of the present invention will be described with reference to the detailed description of fig. 1 to 23.

In some of the drawings, some of the components are omitted or simplified for clarity of illustration.

As shown in fig. 1, the endoscope 10 includes a hollow elongated insertion portion 20 that is inserted into a lumen such as a body cavity, and an operation portion 30 that is coupled to a proximal end side of the insertion portion 20 and operates the endoscope 10.

The insertion portion 20 includes an I-th bending portion 21, an II-th bending portion 22, and a flexible tube portion 23 in this order from the distal end side of the insertion portion 20 toward the proximal end side of the insertion portion 20. The first bending portion 21 is provided on the distal end side of the insertion portion 20, and the insertion portion 20 is actively bent in a desired direction by the operation portion 30, and the base end side of the second bending portion 22 is continuously connected to the distal end side of the flexible tube portion 23 in bending, and the second bending portion 22 has rigidity and flexibility, and is passively bent when an external force is applied thereto. The structure of the second bending portion 22 will be described later.

By performing bending operation on the i-th bending portion 21, for example, in a desired direction up, down, left, and right. The object to be observed can be captured in the observation field by illuminating the object to be observed with the illumination light. The observation target is, for example, a site to be observed in a subject (for example, a body cavity).

As shown in fig. 2, the i-th bending portion 21 may have a rope threading hole, and the i-th bending portion 21 is provided on the distal end side of the insertion portion 20, and has a plurality of, for example, substantially cylindrical (ring-shaped) knuckle wheels 211, and actively bends by pulling a wire. The adjacent ones of the plurality of joint wheels 211 are rotatably coupled to each other, whereby the I-th bending portion 21 is configured to be bendable (rotatable), and the rigidity of the I-th bending portion 21 may be rigidity in a state in which the wire is not subjected to force. Adjacent joint wheels 211 are rotatably connected to each other by a connecting member such as a pin, and the second bending portion 22 is provided on the base end side of the first bending portion 21, and is passively bent when an external force is applied thereto, so that the first bending portion 21 and the second bending portion 22 are connected, and the flexible tube portion 23 and the second bending portion 22 are connected.

The second bending portion 22 may be a hollow tube made of stainless steel, the hollow tube 24 directly forming the second bending portion 22 is provided with a plurality of bending joints by adopting a laser cutting method or the like, the second bending portion 22 is formed by integrally forming the plurality of bending joints, each bending joint is provided with a side wall notch 241 and a bearing portion 242, the bearing portion 242 is formed by a part of the wall of the hollow tube, and the side wall notch 241 cut by adopting the laser cutting method or the like and the bearing portion 242 remained after cutting cooperate, so that the second bending portion 22 is passively bent under the action of external force, the second bending portion 22 formed by the hollow tube 24 is not provided with a wire, and is not subjected to traction force of the wire, and a certain degree of bending can occur under the action of the transmission force of the first bending portion 21 or body cavity tissues or the like.

The cut on any of the bending sections has two free ends in the circumferential direction of the hollow tube 24 at the side wall notch 241, and the two free ends are located on the same circumference of the side circumferential surface of the hollow tube 24. It will be appreciated that when the side wall notch 241 and the carrying portion 242 are formed in a cutting manner, the corresponding cutting surface of the side wall notch 241 is formed by cutting in parallel to the bottom surface of the cylindrical hollow tube 24, the direction of the free end of the formed side wall notch 241 is along the tangential direction of the side surface of the hollow tube 24, and the formed side wall notch 241 and the carrying portion 242 are parallel to the bottom surface of the hollow tube 24 and perpendicular to the length axis HH of the hollow tube 24. The bearing parts 242 are formed by partial pipe walls of the hollow pipe 24 with a predetermined arc length, and the connecting line between the central points of at least two bearing parts 242 on the same bending joint on the hollow pipe 24 is approximately coincident with the symmetrical line of the cross section of the hollow pipe 24 or the diameter of the cross section of the cylindrical hollow pipe, so that the hollow pipe 24 is prevented from being stretched, compressed or deformed in torsion when being passively bent by external force.

As shown in fig. 3 to 4, the active bending section at the distal end of the insertion portion 20 is actively bent by a bending operation of pulling the wire 26, and is actively bent in any one of 4 directions, i.e., up, down, left, and right, or any one of a combination of 2 directions, i.e., up, down, left, and right, the flexible tube 27 is provided on the outer periphery of the wire 26, and is fixed to the end of the II-th bending portion 22 on the side of the I-th bending portion 21, the flexible tube 27 penetrates the outer periphery of the wire 26 to form a protection channel, and a plurality of flexible tubes 27 corresponding to the plurality of wires 26 are fixed at one end of the II-th bending portion 22 at intervals in the circumferential direction, and the specific fixing method may be fixed by a fixing method such as welding or a fixing ring, without limitation.

In one embodiment, the flexible tube 27 may be a spiral spring tube, a flexible plastic tube, a thin-walled plastic or metal tube with spiral cutting grooves, etc. which can provide a receiving cavity for the wire 26 and can be bent, but is not limited thereto.

In an embodiment, the II bending portion 22 and the fixing portion 28 of the flexible tube 27 may be integrally formed, the fixing portion 28 may be a fixing ring formed by cutting the hollow tube 24 along its circumferential direction, etc., and the integrally formed manner may further reduce additional fixing fittings, and may also reduce the length of the connecting portion including the non-bendable section, so that the overall bending of the passive bending is more coordinated.

As shown in fig. 5, when the two free ends 2411, 2422 of the sidewall notch 241 are located on the same circumference of the side circumferential surface, the direction of the free ends coincides with the tangential direction of the side circumferential surface of the hollow tube 24, and when the connecting line of the two bearing portions 242 coincides with or substantially coincides with the symmetry line of the cross section of the hollow tube 24, the hollow tube 24 includes two side circumferential surfaces formed by the two sidewall notches 241, respectively, the hollow tube 24 is formed into three sections a, B, C, and on the first side circumferential surface, bearing portions 242a,242B are formed, and during the mirror withdrawal process, when the hollow tube 24 receives a tensile force, a tensile force F _1-1 and a reaction force F _1-1' are generated in the bearing portion 242a, a tensile force F _2-1 and a reaction force F _2-1' are generated in the bearing portion 242B, and these two groups of forces are equal and opposite, and when the connecting line of the bearing portions 242a and 242B coincides with or substantially coincides with the symmetry line of the cross section of the hollow tube 24, the bearing portion itself is not subject to a force of a side offset force; on the second side peripheral surface, the carrying portions 242c,242d are formed, which will not be described here. Similarly, during the mirror insertion, the II-th bending portion 22 receives the same reaction force at each portion when compressed by an external force, and keeps the longitudinal axis direction less deformable. Therefore, the side wall notch 241 and the bearing portion 242 formed by the cutting process can keep the length of the passive bending portion fixed when the II bending portion 22 receives an external force, and the passive bending portion is only bent and deformed, so that the occurrence of tensile deformation in the longitudinal axis direction can be avoided. Therefore, fatigue resistance of the II-th bending portion 22 can be enhanced, and at the same time, the passive bending performance degradation caused by elongation along the length axis direction in the bending process of the passive bending portion can be prevented, risks such as breakage and dislocation of the II-th bending portion can be greatly reduced, and performance and reliability of the passive bending portion can be further improved.

Further, when the bearing portion 241 on the bending section corresponding to the first side circumferential surface is deflected relative to the bearing portion 242 on the bending section corresponding to the second side circumferential surface, the axes of the bearing portions 242a and 242b and the axes of the bearing portions 242c and 242d are symmetrically arranged, and the passive bending portion only performs bending deformation and simultaneously can avoid stretching deformation in the length axis direction.

When the insertion portion 2 is inserted into the body cavity, the second bending portion 22 is passively bent by an external force, and the plurality of sidewall notches 241 and the bearing portion 242 are designed so that the hollow tube 24 is not easily deformed by expansion and contraction when receiving a tensile force or a compressive force. The number, width, length, etc. of the sidewall notches 241 and the supporting portions 242 are set so that the maximum bending angle, bending direction, bending rigidity are controllable and adjustable, as will be described in detail below.

As shown in fig. 6, the sidewall notch 241 may also be zigzag in shape.

In other related embodiments, the shape of the sidewall notch 241 may be a regular shape or an irregular shape, such as a wavy shape, a triangular shape, a D-shape, a crescent shape, etc., without limitation.

Further, two adjacent bearing parts 242 are arranged in a deflection manner along the longitudinal axis direction of the hollow tube 24, the bearing parts 242 extending and distributed along the longitudinal axis direction of the hollow tube 24 are arranged in a staggered manner as a whole, the bearing parts 242 staggered and adjacent along the longitudinal axis direction of the hollow tube 24 are regularly changed in a circle around the hollow tube 24, the circumferential deflection angle alpha of the two bearing parts 242 relative to the hollow tube 24 is determined by the number of the bearing parts 242 and the length of the hollow tube 24, and under the condition that the length of the hollow tube 24 is fixed, the more the number of the bending joints is, namely the more the number of the bearing parts 242 is, the smaller the deflection angle alpha of the two bearing parts 242 adjacent along the longitudinal axis direction of the hollow tube 24 is, and the smaller deflection angle alpha can maintain the good bending coordination of the passive bending part in the circumferential direction.

As shown in fig. 7 to 22, the passive bending portion has a plurality of side wall notches 241 and a plurality of bearing portions 242, and the bearing portions 242 are the remaining portions of the side wall notches 241 cut on the side circumferential surface of the hollow tube 24, that is, are formed by a portion of the tube wall having a predetermined arc length along the side circumferential surface of the hollow tube 24, and the plurality of side wall notches 241 sequentially have a setting of a certain deflection angle in the length axis direction of the hollow tube, so that the side wall notches 241 are arranged in a spiral or approximately spiral shape along the length axis direction of the hollow tube 24. Other arrangements are not limited as long as the overall flexibility of the passive bending portion is made more uniform.

In one embodiment, the hollow tube 24 including the plurality of sidewall notches 241 and the plurality of bearing portions 242 may be formed as an integrally formed hollow tubular structure with two ends open.

In an embodiment, the same circumference corresponding to the same bending section along the side circumferential surface of the hollow tube 24 may include a plurality of side wall notches 241, the plurality of side wall notches 241 along the same circumference of the hollow tube 24 are arranged in a staggered manner along the length axis direction of the hollow tube 24 at a certain angle, the plurality of side wall notches 241 make the bending of the hollow tube 24 in all directions under the action of external force unrestricted, so that the bending freedom degree of 360 ° in the circumferential direction can be improved, and the number of the side wall notches 241 or the bearing parts 242 can be 2,3 or more on the same circumference of the hollow tube 24 by the side wall notches 241 without limitation.

In an embodiment, the notch section formed by the sidewall notch 241 is perpendicular to the length axis direction of the hollow tube 24, so that high precision machining in the micrometer scale can be realized, the hollow tube of the second bending portion 22 is not affected by mechanical stress or deformation, and the risk of workpiece damage is reduced.

As shown in fig. 7 to 10, the side wall notches 241 of the hollow tube 24 arranged in the longitudinal axis direction of the hollow tube 24 in the hollow tube circumferential direction are arranged in a spiral shape along the I-th bending portion 21 toward the flexible tube portion 23. The same circumference of the hollow tube 24 includes a plurality of sidewall notches 241 and a plurality of bearing portions 242, the number of sidewall notches 241 and the bearing portions 242 on the same circumference along the side circumferential surface on the same bending joint may be the same, the deflection angle α between two bearing portions 242 that are offset adjacent in the longitudinal axis direction of the hollow tube 24 in two adjacent bending joints may be any suitable angle smaller than 90 °, and when an external force is applied, the edges of two sidewall notches 241 that are adjacent to the hollow tube 24 in the longitudinal axis direction are pressed and abutted, the ii-th bending portion 22 has a maximum bending angle that is independent of the bending direction.

For example, when the predetermined arc length l of the bearing portion 242 along the hollow tube 24 is equal, it corresponds to that the first angles β of 360 ° along the circumferential direction of the hollow tube 24 are equal, the second angles θ of 360 ° along the circumferential direction of the hollow tube of the plurality of sidewall notches 241 are also equal, the first angles β may be any value of 20 °, 15 °,10 °,5 °, etc., and the second angles θ of each sidewall notch 241 along the circumferential direction of the hollow tube correspond to one of 160 °, 165 °, 170 °, 175 °, i.e., the sidewall notches 241 are symmetrically disposed along the length axis direction and the circumferential direction of the hollow tube 24. The rigidity of the hollow tube 24 is adjusted by the carrier 242 along a predetermined arc length l (first angle β) in the circumferential direction of the hollow tube.

When the bearing portion 242 is adjusted at the first angle β with respect to the hollow tube circumferential direction, it is achieved that the II-th bending portion 22 is formed to be less rigid than the flexible tube portion 23 and greater than the i-th bending portion 21, maintaining good insertability of the insertion portion 20.

For example, the first angles β of the two bearing portions 242 on the same circumference in the direction near the first bending portion 21 with respect to the hollow tube circumferential direction of the hollow tube 24 are respectively 10 °, 170 °, and the second angles θ of the two side wall notches 241 with respect to the second angle θ in the direction near the hollow tube circumferential direction of the flexible tube portion 23 are respectively 40 °, 140 °, and 140 °, respectively, the first angles β exhibit an increasing or gradually increasing tendency in the direction from the first bending portion 21 to the flexible tube portion 23, so that the predetermined arc length l of the bearing portion 242 exhibits an increasing or gradually increasing tendency, so that the rigidity on the base end side near the flexible tube portion 23 is greater than the rigidity on the front end side near the direction of the first bending portion 21, and the rigidity of the insertion portion 20 is more compliant with the change in rigidity of the insertion portion 20.

As shown in fig. 11 to 14, by further adjusting the first angle β of the bearing portion 242 with respect to the circumferential direction of the hollow tube 24, the rigidity of the II-th bending portion 22 is adjusted to a proper value or a proper gradual trend so as to satisfy the requirement of passive bending. When the deflection angle α between the two bearing portions 242 adjacent to each other in the longitudinal axis direction misalignment of the hollow tube 24 is 60 ° or less, the bending degree of freedom in the circumferential direction of the passive bending portion is further improved. The hollow tube 24 may include more than two sidewall notches 241 and bearing portions 242 on the same circumference, and the first angle β corresponding to any two adjacent bearing portions 242 on the same circumference of the hollow tube 24 may be any suitable value smaller than 60 ° corresponding to 10 °, 20 °, 30 °, 40 °, etc., which is merely exemplary, but not exhaustive.

For example, when three side wall notches 241 and three bearing portions 242 are included on the same circumferential line in the hollow pipe circumferential direction in the direction approaching the i-th bending portion 21, the first angles β of the bearing portions 242 with respect to the circumferential direction of the hollow pipe 24 are 10 °, respectively, the second angles θ of the side wall notches 241 with respect to the hollow pipe 24 are 110 °, respectively, at one end of the hollow pipe 24 near the flexible pipe portion side, the first angles β are 30 °, and the second angles θ are 90 °, respectively, the first angles β exhibit a tendency to increase or gradually increase in a direction along the i-th bending portion 21 to the flexible tube portion 23, and rigidity thereof increases with an increase in the first angles β, so that rigidity of the passive bending portion gradually increases toward the flexible tube portion 23.

Also, the number of the bearing parts 242 may be defined according to the number of the sidewall notches 241 on the same circumference of the hollow tube 24, and the first angles β of the plurality of bearing parts 242 along the same circumference of the hollow tube 24 may not be identical, and may be set to a proper angle of not more than 60 °. The first angle beta and the second angle theta described above are merely examples and are not exhaustive.

As shown in fig. 15 to 18, a plurality of bending sections adjacently arranged along the length axis direction of the hollow tube 24 are formed into one array unit, a plurality of side wall notches 241 in each array unit are distributed at equal intervals around the circumference of the hollow tube 24, the side wall notches 241 in each array unit are relatively deflected to 360 degrees between the initial bending section of the array unit and the final bending section of the current array unit, that is, the bearing part 242 in each array unit presents a periodical change along the length axis direction of the hollow tube 24, and by adjusting one or more values of the notch width d of the side wall notch 241 in the array unit and the predetermined arc length l of the bearing part 242, the passive bending part formed by the hollow tube 24 achieves multistage gradient of the radius of curvature and/or rigidity at the time of maximum bending along the direction of the I-th bending part 221 to the direction of the flexible tube part 23, so that the passive bending achieves transition in a more uniform manner, reduces the incongruity at the time of 360 ° bending of the circumference of the bending part to the maximum extent, and is more convenient for the progress of patients.

For example, as shown in fig. 15 to 16, the plurality of bending sections of the hollow tube 24 form 4 array units AB, BC, CD, DE, the dimension of the side wall notch 242 along the length axis direction of the hollow tube 24 is a notch width d, the notch widths d of the side wall notches 242 of the same array unit are equal, the notch widths d1, d2, d3, d4 of different array units AB, BC, CD, DE are in a decreasing trend along the direction from the first bending section to the flexible tube section, and the notch widths d1 > d2 > d 3> d4 of the side wall notch 241 are shown; the 4 array units can realize the bending radius R1< R2< R3< R4 when 4 different maximum bending, and can realize multistage gradual change for the passive bending part, so that the passive bending is more uniform in bending transition when receiving external force, and the operation of entering, exiting, and the like is more convenient.

Specifically, the sidewall notches 241 in the 4 array units may be presented in a graded manner of 1.2mm, 1.0mm, 0.8mm, and 0.6mm according to the notch width d ₁、d₂、d₃、d₄ and extend to two ends of the hollow tube 24, so that the transition of the bending radius change of the passive bending portion when the passive bending portion is subjected to an external force is more uniform and gentle, the entrance is more convenient, and the discomfort of the patient is reduced.

For example, as shown in fig. 17 to 19, the carrying portion 242 rotates in the length axis direction in one array unit, each 8 carrying portions 242 forms a cycle, the plurality of bending joints of the hollow tube 24 form 4 array units AB, BC, CD, DE, the predetermined arc length l of the carrying portion 242 in each array unit is equal, the carrying portions 242 of different array units have a size in the length axis direction of the hollow tube 24 that is the increasing trend of the predetermined arc length l of the carrying portion 242 along the i-th bending portion 21 to the flexible tube portion direction 23, so that the first angle of the 4 array units satisfies the predetermined arc length l1< l2< l3< l4 of the carrying portion 242 of β1< β2< β3< β4, when the hollow tube 24 is bent in different directions, the 4 array units can realize 4 different bending rigidities S1, S2, S3, S4, and S4 > S3 > S2 > S1, the relative rotation angle of the carrying portion 242 in each array unit is smaller, and the hollow tube 24 is subjected to a small degree of external force 360 ° when being bent in the circumferential direction.

Further, one or more values of the gap width d of the sidewall gap 241, the predetermined arc length l of the bearing portion 242, etc. in the array unit may be adjusted at the same time, so as to further improve the bending performance of the passive bending. For example, the predetermined arc length l and the notch width d of the carrying portion 242 in each array unit may be adjusted to be non-gradually changed in different array units, so that the bending performance of the passive bending is not limited.

Therefore, the second bending portion 22 is formed to have a rigidity smaller than the flexible tube portion 23 and larger than the first bending portion 21, and the second bending portion 22 is formed to have a radius of curvature smaller than the flexible tube portion 23 and larger than the first bending portion 21 when being maximally bent, and the rigidity and the radius of curvature of the passive bending portion are changed stepwise in multiple stages, so that the insertion portion makes a more gentle transition when being inserted into the body cavity. Further, for the hollow tube with a fixed length, by increasing the number of bending joints and the number of array units, the bending radius and the gradual change of rigidity change of the second bending part 22 when the second bending part is subjected to external force are more gentle, the incompatibility of bending is reduced to a greater extent, and the multistage gradual change of the bending radius during the maximum bending is realized.

As shown in fig. 20 to 21, in the case where the length of the tube body member 24 is unchanged, the number of bending joints is further increased so that the number of the bearing portions 242 is correspondingly increased, the bearing portions 242 which are offset adjacent in the length axis direction of the hollow tube 24 exhibit a regular change throughout the hollow tube 24 in a circle around the hollow tube 24, so that the deflection angle α of the bearing portions 242 which are offset adjacent in the length axis direction of the hollow tube 24 in the hollow tube circumferential direction is reduced, and the bearing portions 242 are evenly offset arranged in 360 ° in the circumferential direction. Under the condition that the length of the second bending part 22 is kept unchanged, the deflection angle alpha of two adjacent bearing parts along the length axis direction of the hollow pipe is reduced, so that the reduction of the deflection angle alpha can improve the integral bending coordination when the second bending part 22 is bent by 360 degrees along the circumferential direction, the pipe is favorable for dispersing stress when bearing external load and pressure, and the stability and the reliability of the passive bending part are enhanced.

Specifically, in an embodiment, when the length of the hollow tube 24 is fixed, the number of the bearing portions 242 is increased by a multiple when the number of the bending joints is doubled, and the deflection angle α of two bearing portions 242 offset from each other along the length axis direction of the hollow tube 24 is correspondingly reduced to one half. For example, when the number of bent sections of the hollow tube 24 of the same length is increased and the number of the bearing portions 242 is increased from N to 3N (N is a positive integer), the corresponding deflection angle α may be reduced from 60 ° to 15 °. The deflection angle α may be smaller than a certain suitable deflection angle of 90 ° for the bearing portions, and the deflection angles α corresponding to the relative deflection setting of two bearing portions 242 that are randomly staggered and adjacent may be equal, where the bearing portions 242 are spirally arranged along the length axis direction of the hollow tube 24, so that the I-th bending portion 22 has stronger deformation resistance and damage resistance when bearing the effects of pressure, tensile force, and the like on the circumferential direction 360 °. The values of the deflection angle alpha described above are merely exemplary and not exhaustive.

It will be appreciated that where the number of sidewall indentations 241 located on the same or approximately the same circumference along the side circumferential surface of the curved section of the hollow tube 24 is determined, the rigidity and radius of curvature of the hollow tube 24 may be determined by changing one or more of the adjustable structural parameters of the first angle β (predetermined arc length l) of the bearing portion 242, the second angle θ of the sidewall indentations 241 along the circumferential direction of the hollow tube 24, the gap width d of the sidewall indentations 241, the deflection angle α of adjacent sidewall indentations 241 along the longitudinal axis of the hollow tube, etc., such that the ii-th curved portion 22 may compromise the bending rigidity, the bending radius of curvature, and the coordination of the bending of the ii-th curved portion 22 while ensuring good insertion compliance of the insertion portion 20.

As shown in fig. 22, by changing the wall thickness of the hollow tube of the second bending portion 22 such that the thickness t of the hollow tube 24 in the direction approaching the flexible tube portion 23 or the average thickness is not smaller than the thickness or the average thickness in the direction of the first bending portion 21 or the thickness of the hollow tube in the direction 21 of the first bending portion along the flexible tube portion 23 gradually decreases, the rigidity of the second bending portion 22 in the base end side approaching the flexible tube portion 23 is made larger than the rigidity in the front end side approaching the first bending portion 21.

Further, the wall thickness t of the hollow tube 24 gradually decreases along the flexible tube portion 23 toward the first bending portion direction 21, which means that the inner diameter of the hollow tube 24 may be regularly tapered, and that the rigidity and the curvature radius of the hollow tube 24 may be reduced accordingly, so that the second bending portion 22 satisfies the bending requirement of the passive bending portion.

Moreover, by adjusting the gap width d of the second bending portion 22, such as the sidewall gap 241, the predetermined arc length l (the first angle β) of the bearing portion 242, the deflection angle α between two adjacent bearing portions of the hollow tube 24, the number of sidewall gaps 241, the gap shape, the wall thickness t of the hollow tube 24, and other one or more adjustable structural parameters, the second bending portion 22 can be made to have the bending rigidity of the second bending portion 22, the radius of curvature at the time of maximum bending, and the coordination of the bending portions, so as to maintain the good insertion compliance of the insertion portion 20.

In an embodiment, the gap width of the sidewall gap 241 of the connecting portion at two ends of the hollow tube 24 in the length axis direction is not smaller than the width value of the sidewall gap at any other position of the hollow tube 24, and the limitation of the gap width d reduces the incongruity of the radius of curvature transition caused by the connecting portion between the first bending portion 21 and the second bending portion 22 and the non-bendable section of the connecting portion between the flexible tube portion 23 and the second bending portion 22, so that the bending transition of the second bending portion 22 at two ends of the length axis direction is smoother.

Further, the notch width of the side wall notch 241 of the hollow tube 24 of the second bending 22 in the direction approaching the first bending portion 21 and to which the connecting portion of the first bending portion 21 is connected and the hollow tube 24 of the second bending portion 22 in the direction approaching the first bending portion 21 and to which the connecting portion of the first bending portion is connected may each correspond to the maximum (maximum) value of the notch width, or one of them corresponds to the maximum value of the notch width.

Therefore, the design that a plurality of bending joints on the hollow tube are realized through the side wall notch and the design of a plurality of bearing parts, and meanwhile, the design that the flexible tube penetrates through the passive bending part is realized, so that the passive bending part and the lens of the endoscope are always kept in close contact with the surface of the intestinal tract or the airway, the compliance of the natural cavity bending when the endoscope is acted can be improved, the definition and the visibility of the visual field are improved, a doctor can observe the lesion part in a patient better, and the efficiency and the precision of the operation of the endoscope are improved.

In an embodiment, the hollow tube 24 of the second bending portion 22 is adjacent to and connected to the first bending portion 21, and the outer diameter of the hollow tube 24 is equal to the inner diameter of the connecting portion of the first bending portion 21, and the second bending portion 22 can be connected to the first bending portion 21 by sleeving, so that when the first bending portion 21 and the second bending portion 22 are relatively bent, the bending transition portion is smoother than the screw fixing connection, and meanwhile, the sleeving manner can shorten the length of the connecting portion, so that the different curvature radii between the first bending portion 21 of the active bending portion and the second bending portion 22 of the passive bending portion are changed or gradually changed to be smoother and smoother.

In an embodiment, the hollow tube 24 is formed in a section adjacent to and connected to the first bending portion 21, and the outer diameter of the hollow tube 24 in the section may be smaller than the inner diameter of the connecting section of the first bending portion 21, and the connection of the second bending portion 22 and the first bending portion 21 may be achieved by punching.

In an embodiment, the hollow tube 24 of the second bending portion 22 is connected to the first bending portion 21 and the flexible tube portion 23 respectively, and the connection may be achieved by punching, sleeving, fastening with a screw, or the like, which is not limited herein.

As shown in fig. 23, a protective layer 25 covering the outer periphery of the hollow tube 24 may be formed of a rubber material. The two ends of the protection layer 25 and the II bending part 22 are fixed to prevent the side wall notch of the hollow tube 24 from contacting the outer skin to clamp the outer skin, and the protection layer 25 separates the II bending part 22 from the outer skin, so that the outer skin is protected from being damaged.

The protective layer 25 is formed by, for example, forming a thin stainless steel wire into a plurality of bundles and braiding them into a lattice shape to be tubular, forming a stainless steel wire or a stainless steel coil into one or more spiral shapes to be tubular, forming one or more coils into a tubular shape by alternately winding the one or more coils into a plurality of layers with different winding directions, or forming the protective layer 25 including a predetermined shape such as a lattice shape by laser cutting.

In the present invention, the outer skins covering the I-th bending portion 21, the ii-th bending portion 22 and the flexible tube portion 23 are adjusted to have different thicknesses or different materials, so that the ii-th bending portion 22 is formed to have rigidity lower than the flexible tube portion 23 and higher than the I-th bending portion 21, and the radius of curvature of the ii-th bending portion 22 at the time of maximum bending is smaller than the flexible tube portion 23 and larger than the radius of curvature of the I-th bending portion 21 at the time of maximum bending.

In the present invention, the I-th bending portion 21, the ii-th bending portion 22, and the flexible tube portion 23 may be covered with protective layers having different thicknesses, different knitting densities, different materials, etc., and the ii-th bending portion 22 may be formed to have a rigidity lower than the flexible tube portion 23 and higher than the I-th bending portion 21 by adjusting the knitting density, knitting material, etc., and the ii-th bending portion 22 may be formed to have a radius of curvature smaller than the flexible tube portion 23 and larger than the radius of curvature of the I-th bending portion 21 when the bending portion is maximally bent.

The difference of hardness (rigidity) of the first bending part, the second bending part and the flexible tube part is realized through the difference of one or more hardness (rigidity) of the first bending part 21, the second bending part 22 and the flexible tube part 23, the hollow tube outer cladding protective layer, the sheath and the like, so that the rigidity of the second bending part 22 and the radius of curvature in the maximum bending are both larger than those of the first bending part and smaller than those of the second bending part, simultaneously, the good insertion property of the second bending part is maintained, the gap design shape, the gap width, the gap number on the hollow tube, the structural shape of the bearing part, the design of the preset arc section length of the bearing part and the like can be used for adjusting the bending rigidity of the passive bending part of the insertion part in a large range and accurately, the bending flexibility is improved, a doctor can bend and turn in the operation process conveniently, the operation efficiency and accuracy are improved, and meanwhile, the endoscope is smoother and stable in the bending process, thereby the doctor can observe the lesion part in the patient better, the passive bending part has better compliance, and discomfort of the patient can be relieved.

As described above, the i-th bending portion 21 is set to be very soft, and the flexible tube portion 23 is set to have a hardness that is harder than the II-th bending portion 22 and that allows the flexible tube portion 23 to have a predetermined flexibility required for insertion into the body cavity, so that the II-th bending portion 22 can achieve a bending transition more favorably.

The present disclosure is, therefore, to be considered as illustrative and not restrictive. The description and illustrations of the embodiments described herein are intended to provide a general understanding of the structure of various embodiments. The description and examples are not intended to serve as an exhaustive and comprehensive description of all of the elements and features of apparatus and systems that use the structures or methods described herein. Individual embodiments may also be provided in combination in a single embodiment, conversely, individual features that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any subcombination. Furthermore, references to values stated in ranges include each value in the range. Many other embodiments will be apparent to those of skill in the art upon reading this specification only. Other embodiments may be utilized and derived from the disclosure, such that structural, logical substitutions, or any changes may be made without departing from the scope of the disclosure.

Claims

1. An insertion device having an insertion portion that is inserted from a distal end side into a subject in a longitudinal axis direction, the insertion portion comprising:

an I-th bending part provided at a front end side of the insertion part and actively bending by pulling the wire;

the II bending part comprises a hollow pipe formed by a plurality of bending joints, and the hollow pipe is integrally formed;

each bending joint comprises a side wall notch and a bearing part;

a connecting line between the central points of at least two bearing parts on the same bending joint is approximately coincident with a symmetrical line of the cross section of the hollow tube;

The rigidity of the second bending part is smaller than that of the flexible pipe part and larger than that of the first bending part, and the radius of curvature of the second bending part in the maximum bending is smaller than that of the flexible pipe part in the maximum bending and larger than that of the first bending part in the maximum bending.

2. The insertion device of claim 1, further comprising: and a flexible tube which is provided on the outer periphery of the wire and is fixed to one end of the second bending portion on the side close to the first bending portion.

3. The insertion device of claim 1, wherein the bearing portions on two of the flexure sections adjacent in a longitudinal axis direction are provided with relative deflection.

4. The insertion device of claim 1, wherein a plurality of the curved sections disposed adjacently along a length axis direction of the hollow tube are formed as one array unit, and a plurality of the sidewall indentations in each of the array units are equally spaced around a circumference of the hollow tube.

5. The insertion device of claim 4, wherein the sidewall indentations of the same array element have equal indentation widths, the indentation widths of different array elements having a decreasing trend along the i-th bend to the flexible tube portion direction.

6. The insertion device of claim 4, wherein the predetermined arc lengths of the carrying portions of the same array unit are equal, the predetermined arc lengths of the carrying portions of different array units having an increasing trend along the i-th bending portion to the flexible tube portion direction.

7. The insertion device according to claim 1, wherein a gap width of the side wall gap at the connecting portion of both ends in the longitudinal axis direction of the hollow tube is not smaller than a gap width of any of the other side wall gaps.

8. The insertion device of claim 1, further comprising a protective layer covering an outer periphery of the II-th bending portion, and the protective layer is fixedly connected to both ends of the II-th bending portion.

9. The insertion device of claim 1, wherein a wall thickness of the hollow tube increases in a direction from the ith bend to the flexible tube portion.

10. An endoscope comprising the insertion device of any one of claims 1 to 9.