Passive bending part of endoscope and endoscope

Abstract

The invention provides a passive bending part of an endoscope and the endoscope. The passive bending part of the endoscope is arranged on an insertion part of the endoscope, the insertion part is inserted into a detected body from the front end side in the length axis direction, the passive bending part comprises a snake bone assembly, and the snake bone assembly comprises a plurality of snake bone joints which are hinged in sequence; the passive bending part further comprises a woven mesh, the woven mesh is arranged on the peripheral face of the snake bone assembly in a sleeving mode, and the woven mesh comprises a plurality of woven mesh units connected in sequence; and when each woven mesh unit is bent to the maximum bending angle, the passive bending part reaches the maximum bending angle. A woven mesh is arranged on the peripheral face of a snake bone assembly in a sleeving mode and comprises a plurality of woven mesh units connected in sequence, when each woven mesh unit is bent to the maximum bending angle, a passive bending part reaches the maximum bending angle, and a gap is kept between every two adjacent snake bone joints; the woven mesh has elasticity and cannot be meshed between the adjacent snake joints at the maximum bending angle, the performance of the woven mesh is improved, and the service life of the woven mesh is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of endoscopes, and in particular to a passive bending part of an endoscope and an endoscope. Background Art

[0002] Medical endoscopes, especially flexible endoscopes, are important instruments that can be inserted into the human body cavity for direct examination and surgical treatment, and are a common method for peeping into the internal cavity of the human body. Among them, a flexible endoscope usually adds a section of passive bending part between the active bending part and the flexible part, so that the bending angle range of the endoscope is larger, eliminating the visual field blind area and making the endoscope examination and treatment easier.

[0003] The passive bending part is mainly used to adapt to the shape of the cavity and reduce the discomfort of the patient when inserted into the human body cavity. The passive bending part is bent passively by receiving an external force. When the endoscope is inserted into the human body cavity, the passive bending part will naturally bend according to the shape of the cavity to adapt to the bending path of the cavity. The passive bending part includes a plurality of serially connected snake bone joints, and the snake bone joints are movably connected by processes such as clamping and riveting to form a snake bone assembly. When the existing passive bending part is bent, the adjacent snake bone joints achieve the maximum bending of the passive bending part in a mutually abutting manner. When the adjacent snake bone joints abut, a smooth transition cannot be achieved between the adjacent snake bone joints, and the overall passive bending part is not smooth enough when bending in the body cavity, making it difficult to observe some lesions, increasing the pain of the patient and prolonging the operation time; at the same time, the metal mesh belt braid layer and the snake bone assembly will interfere with each other, resulting in damage to the metal mesh belt braid layer. Summary of the Invention

[0004] The present invention provides a passive bending part of an endoscope to solve the problems that when the existing passive bending part achieves the maximum bending angle, the abutting contact between the snake bone joints is likely to damage the metal mesh belt braid layer and the metal mesh braid layer does not have elasticity and it is difficult to rely on it to achieve the maximum bending angle, etc.

[0005] The present invention provides a passive bending part of an endoscope, which is arranged in the insertion part of the endoscope. The insertion part is inserted into the subject from the front end side along the length axis direction. The passive bending part includes a snake bone assembly, and the snake bone assembly includes a plurality of serially hinged snake bone joints; The passive bending part further includes a braided net, the braided net is sleeved on the outer peripheral surface of the snake bone assembly, and the braided net includes a plurality of serially connected braided net units; When each braided net unit is bent to the maximum bending angle, the passive bending part reaches the maximum bending angle, and there is a gap between adjacent snake bone joints.

[0006] According to a passive bending part of an endoscope provided by the present invention, the braided net is formed by braiding a plurality of metal thin plates into a cylindrical metal tube, and the metal thin plates are formed by arranging a plurality of metal wires in parallel.

[0007] When the passive bending part reaches the maximum bending angle, the outer edges of the thin metal plates in the braided mesh units on the inner side along the bending direction of the braided mesh abut against each other.

[0008] An endoscope passive bending part provided by the present invention, the stiffness of each of the braided mesh units is equal, and the braided mesh is in transitional fit with the snake bone assembly.

[0009] An endoscope passive bending part provided by the present invention, the stiffness of multiple braided mesh units varies periodically. Among them, the stiffness of the braided mesh unit sleeved on the outer periphery of the snake bone segment is less than the stiffness of the braided mesh unit sleeved at the arc section between two adjacent snake bone segments.

[0010] An endoscope passive bending part provided by the present invention, the braided mesh unit includes at least two sequentially connected braided mesh components, and the stiffness of the braided mesh component with the largest stiffness gradually increases along the direction from the front end side to the base end side of the insertion part.

[0011] An endoscope passive bending part provided by the present invention, the braided mesh unit includes a first braided mesh component and a second braided mesh component connected to the first braided mesh component, and the stiffness of the first braided mesh component is less than the stiffness of the second braided mesh component.

[0012] An endoscope passive bending part provided by the present invention, the stiffness of the metal wires of the first braided mesh component is less than the stiffness of the metal wires of the second braided mesh component.

[0013] An endoscope passive bending part provided by the present invention, the braiding angle of the first braided mesh component is less than the braiding angle of the second braided mesh component.

[0014] An endoscope passive bending part provided by the present invention, the braided mesh unit includes a first braided mesh component, a second braided mesh component, a third braided mesh component, and a fourth braided mesh component connected in sequence. The stiffness of the first braided mesh component is less than the stiffness of the second braided mesh component, the stiffness of the second braided mesh component is less than the stiffness of the third braided mesh component, and the stiffness of the fourth braided mesh component is equal to the stiffness of the second braided mesh component.

[0015] The present invention also provides an endoscope, including: the endoscope passive bending part described in any one of the above; a flexible part, the flexible part is arranged on the base end side of the passive bending part; an active bending part, the active bending part is arranged on the front end side of the passive bending part; the bending radius of the passive bending part is greater than the bending radius of the active bending part.

[0016] The passive bending part of the endoscope provided by the present invention is formed by sleeving a braided net on the outer peripheral surface of the snake bone assembly. The braided net includes a plurality of sequentially connected braided net units. When each braided net unit is bent to the maximum bending angle, the passive bending part reaches the maximum bending angle, and there is a gap between adjacent snake bone segments; the way of keeping a gap between adjacent snake bone segments enables the bending of the entire passive bending part to achieve a smooth transition. The bending of the overall passive bending part in the body cavity is smooth enough to meet the clinical needs of observing lesions, and at the same time, it can better adapt to the bending path of the cavity, reducing the discomfort of clinical patients. Further, in this way, the braided net will not be bitten between adjacent snake bone segments, which damages the braided net and prolongs the service life of the braided net. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 is a schematic structural diagram of the endoscope provided by the present invention.

[0019] Figure 2 is a schematic side sectional structural diagram of the flexible part, the passive bending part and the active bending part provided by the present invention.

[0020] Figure 3 is a schematic structural diagram of the connection relationship between the passive bending part and the active bending part of the existing endoscope provided by the present invention.

[0021] Figure 4 is a schematic side sectional structural diagram of the passive bending part of the endoscope provided by the present invention.

[0022] Figure 5 is one of the schematic side structural diagrams of the braided net provided by an embodiment of the present invention.

[0023] Figure 6 is a schematic structural diagram of the braided net unit provided by the present invention.

[0024] Figure 7 is Figure 6 a partial enlarged structural diagram at A in

[0025] Figure 8 is another schematic side structural diagram of the braided net provided by an embodiment of the present invention.

[0026] Figure 9 is a third schematic side structural diagram of the braided net provided by another embodiment of the present invention.

[0027] Figure 10 It is the fourth schematic side view structure diagram of the braided net provided by another embodiment of the present invention.

[0028] Reference numerals: 100, braided net; 110, snake bone assembly; 120, braided net unit; 121, first braided net component; 122, second braided net component; 123, third braided net component; 124, fourth braided net component; 125, wire; 200, operation part; 300, insertion part; 400, flexible part; 500, passive bending part; 600, active bending part; 700, front hard part; 800, transition joint; 900, spring tube. Detailed implementation manners

[0029] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0030] In the description of the embodiments of the present invention, it should be noted that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the embodiments of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0031] In the description of the embodiments of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "connected" and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific situations.

[0032] In the embodiments of the present invention, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the horizontal height of the first feature is less than that of the second feature.

[0033] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0034] Before introducing the passive bending section 500 of the endoscope, the structure of the endoscope will be introduced first. Figure 1 The schematic structural diagram of the endoscope provided by the present invention is illustrated. Figure 2 The schematic side-sectional structural diagram of the flexible section 400, the passive bending section 500, and the active bending section 600 provided by the present invention is illustrated, as Figure 1 and Figure 2 shown, the endoscope includes an operation section 200, an insertion section 300, and a flexible section 400, a passive bending section 500, an active bending section 600, and a front-end rigid section 700 are sequentially arranged along the proximal end side to the front end side of the insertion section 300. Figure 3 The schematic structural diagram of the connection relationship between the passive bending section 500 and the active bending section 600 of the existing endoscope provided by the present invention is illustrated, as Figure 3 shown, in the prior art, the passive bending section 500 is connected to the rear end portion of the active bending section 600 through a transition joint 800, and the passive bending section 500 is bent passively under the action of an external force. Two or four spring tubes 900 are arranged inside the passive bending section 500, and the spring tubes 900 are welded to the transition joint 800. In one embodiment of the present invention, the structure of the braided mesh can omit this spring tube 900 and be realized through the self-return action of the braided mesh.

[0035] Next, in combination with Figures 4 - 10Describe the specific structure of the passive bending part 500 of the present invention.

[0036] Figure 4 Fig. shows a schematic side cross-sectional structure of the passive bending part 500 of the endoscope provided by the present invention. Figure 5 Fig. shows one of the schematic side structures of the braided net provided by an embodiment of the present invention. As Figure 4 and Figure 5 shown, the passive bending part 500 of the endoscope is arranged in the insertion part 300 of the endoscope. The insertion part 300 is inserted into the subject from the front end side along the length axis direction. The passive bending part 500 includes a snake bone assembly 110, and the snake bone assembly 110 includes a plurality of snake bone segments hinged in sequence; the passive bending part 500 further includes a braided net 100, and the braided net 100 is sleeved on the outer peripheral surface of the snake bone assembly 110. The braided net 100 includes a plurality of braided net units 120 connected in sequence; when each braided net unit 120 is bent to the maximum bending angle, the passive bending part 500 reaches the maximum bending angle, and there is a gap between adjacent snake bone segments.

[0037] For the passive bending part 500 of the endoscope provided by the present invention, by sleeving a braided net on the outer peripheral surface of the snake bone assembly, the braided net includes a plurality of braided net units 120 connected in sequence. When each braided net unit 120 is bent to the maximum bending angle, the passive bending part 500 reaches the maximum bending angle, and there is a gap between adjacent snake bone segments; in this way, the braided net will not be bitten between adjacent snake bone segments, which causes damage to the braided net and prolongs the service life of the braided net. In an embodiment of the present invention, the braiding angle of the braided net 100 of the passive bending part 500 is different from the braiding angle of the braided net 100 of the active bending part 600, so that the bending radius of the passive bending part 500 is different from the bending radius of the active bending part 600. In an embodiment of the present invention, the stiffness of the plurality of braided net units 120 changes periodically. Among them, the stiffness of the braided net unit 120 sleeved on the outer periphery of the snake bone segment is less than the stiffness of the braided net unit 120 sleeved on the arc section between adjacent two snake bone segments. In the case where the stiffness of the plurality of braided net units 120 changes periodically, the stiffness of the braided net unit 120 sleeved on the outer periphery of the snake bone segment is made less than the stiffness of the braided net unit 120 sleeved on the connection part between adjacent two snake bone segments; after the braided net 100 and the snake bone assembly 110 are assembled, the outer surface of the passive bending part 500 is uniform and has no obvious protrusions; and the arc sections of the snake bone segments opposite to each other in the snake bone assembly 110 will not directly contact the braided net 100 when bent after being covered by the part with stronger stiffness of the braided net 100, avoiding biting the braided net 100 and causing damage to the braided net 100, and prolonging the service life of the braided net 100.

[0038] It should be noted here that the periodic change in the stiffness of multiple braided mesh units 120 refers to the step - by - step change in the stiffness of multiple braided mesh units 120, that is, the stiffness change law of each braided mesh unit 120 is the same, so that the stiffness of multiple braided mesh units 120 changes periodically along the length direction of the braided mesh 100.

[0039] In one embodiment of the present invention, as Figure 4 shown, the snake bone assembly 110 includes multiple snake bone segments. The edges of the snake bone segments have chamfered arc surfaces with different sizes. The passive bending part 500 realizes its own bending function through the engagement between the opposite arc surfaces of the snake bone segments. The structure of each snake bone segment can be the same or different structures can be set according to the different bending positions of the passive bending part 500. The snake bone segment is usually in a ring - like or similar structure and can bend in multiple directions around the central axis. Adjacent snake bone segments are connected by connecting parts (such as rivets, pivot parts, etc.) to form a continuous bending structure.

[0040] In one embodiment of the present invention, the braided mesh 100 is formed by braiding multiple metal thin plates into a cylindrical metal tube. The metal thin plates are formed by arranging multiple metal wires in parallel. The metal wires 125 are made of high - strength and corrosion - resistant metal materials such as stainless steel and nickel - titanium alloy. These materials can improve the strength and durability of the metal braided mesh. In this embodiment, the metal wires 125 of adjacent two braided mesh components are of the same type of metal wire 125.

[0041] Specifically, Figure 6 illustrates the structural schematic diagram of the braided mesh unit provided by the present invention. Figure 7 is Figure 6 the partial enlarged structural schematic diagram at A in Figure 6 and Figure 7 shown. The widths of adjacent two metal wires 125 are equal. Multiple metal wires 125 are arranged side by side to form a metal thin plate with a larger width. Multiple metal thin plates are braided to form a braided mesh component. In this embodiment, the braiding direction of the braided mesh is from the front end of the passive bending part 500 to the direction of the concentric axis of the rear end. Of course, it can also be braided in the opposite direction to the above, as long as the stiffness of the braided mesh unit 120 meets the above requirements.

[0042] In one embodiment of the present invention, for the passive bending part 500 of the endoscope provided by the present invention, when the passive bending part 500 reaches the maximum bending angle, at the maximum bending angle, the outer edges of the metal thin plates in the braided mesh unit 120 along the inner side of the bending direction of the braided mesh 100 abut against each other, restricting the maximum bending angle of the passive bending part 500.

[0043] Specifically, since the braided mesh 100 has a cylindrical structure, when the metal thin plates used for braiding are subjected to bending forces, the inner metal thin plates will undergo tensile deformation, while the outer metal thin plates will be compressed. On the inner side in the bending direction, the metal thin plates are forced to approach each other due to compression, forming a physical abutment. When the braided mesh 100 is bent, the metal thin plates within the braided mesh unit 120 interact with each other. At the maximum bending angle, the outer edge metal thin plates of the braided mesh unit 120 on the bending direction side will abut against the inner edge metal thin plates of adjacent units. Thus, the limitation of the bending angle of the braided mesh 100 is achieved through the direct contact and mutual abutment of the metal thin plates on this side, ensuring that at the maximum bending angle, the structure of the braided mesh remains stable and a predetermined interval is maintained between adjacent snake bone joints.

[0044] In an embodiment of the present invention, the braided mesh unit 120 includes at least two sequentially connected braided mesh components. The stiffness of the braided mesh component with the greatest stiffness gradually increases in the direction from the front end side to the base end side of the insertion portion 300. Adopting such a stiffness change rule can enhance the resilience of the passive bending portion 500 and enhance the uniformity of the bending state of the passive bending portion 500.

[0045] It should be noted here that the front end of the present invention refers to the end far from the operator when the operator operates the endoscope, and the end close to the operator is the rear end. Specifically, as Figure 5 shown, the left end of the braided mesh 100 is the front end, and the right end of the braided mesh 100 is the rear end.

[0046] In an embodiment of the present invention, as Figure 5 shown, the braided mesh unit 120 includes a first braided mesh component 121 and a second braided mesh component 122 connected to the first braided mesh component 121. The first braided mesh component 121 is located at the front end of the braided mesh unit 120, and the second braided mesh component 122 is located at the rear end of the braided mesh unit 120. The stiffness of the first braided mesh component 121 is less than the stiffness of the second braided mesh component 122. Among them, the first braided mesh component 121 is sleeved on the outer periphery of the snake bone joint and fits with the outer peripheral surface of the snake bone joint, and the second braided mesh component 122 is sleeved on the connection portion between adjacent two snake bone joints and fits with the chamfered arc surface of the snake bone joint. Since the second braided mesh component 122 has a greater stiffness and fits with the connection portion between adjacent two snake bone joints, after the second braided mesh component 122 is assembled with the snake bone component 110, the outer surface of the passive bending portion 500 is uniform and has no obvious protrusions; and the arc-shaped cross-section of the snake bone joint opposite to the snake bone component 110 will not directly contact the second braided mesh component 122 when bent, avoiding biting the second braided mesh component 122 and causing damage to the second braided mesh component 122, thus extending the service life of the braided mesh 100.

[0047] In one embodiment of the present invention, there are various ways to achieve that the stiffness of the first woven mesh component 121 is less than that of the second woven mesh component 122. In this embodiment, the stiffness of the wire of the first woven mesh component 121 is less than that of the second woven mesh component 122. When the first woven mesh component 121 and the second woven mesh component 122 adopt the same weaving angle, to make the stiffness of the first woven mesh component 121 less than that of the second woven mesh component 122, the outer diameter of the wire of the first woven mesh component 121 is less than that of the second woven mesh component 122. Of course, other methods can also be used to change the stiffness of the wire 125.

[0048] It should be noted here that to achieve that the stiffness of the first woven mesh component 121 is less than that of the second woven mesh component 122, in addition to making the stiffness of the wire of the first woven mesh component 121 less than that of the second woven mesh component 122, it can also be achieved by changing the weaving form of the woven mesh component.

[0049] In one embodiment of the present invention, the weaving angle of the first woven mesh component 121 is less than that of the second woven mesh component 122. In this embodiment, the weaving angle of the first woven mesh component 121 is 100°, and the weaving angle of the second woven mesh component 122 is 120°. Of course, the weaving angles of the woven mesh components are not limited to this, and are specifically determined according to actual needs. Since the smaller the weaving angle, the lower the weaving density and the smaller the stiffness, the stiffness of the first woven mesh component 121 is less than that of the second woven mesh component 122. By controlling the change of the weaving angle of the mesh along the insertion direction, different maximum bending angles can be achieved.

[0050] In one embodiment of the present invention, the length of the first woven mesh component 121 is greater than that of the second woven mesh component 122. It should be noted here that the length of the woven mesh component refers to the dimension in the axial direction of the woven mesh 100, that is Figure 5 the dimension in the left - right direction in. Of course, the length relationship between the first woven mesh component 121 and the second woven mesh component 122 is not limited to this, and is specifically determined according to the length of the corresponding snake bone section and the length of the connection between two adjacent snake bone sections.

[0051] In a preferred embodiment of the present invention, the stiffness of the second woven mesh component 122 gradually increases in the direction from the front end side to the base end side of the insertion portion 300, that is, the stiffness of the second woven mesh component 122 gradually increases in Figure 5 the direction from left to right in. By adopting such a setting method, the resilience of the passive bending portion 500 can be enhanced, and the bending state uniformity of the passive bending portion 500 can be enhanced.

[0052] Figure 8 Schematically shows a second side view structure of the woven mesh provided by an embodiment of the present invention, asFigure 8 As shown, in order to better understand the relationship between the stiffness of the braided mesh unit 120 and the stiffness of the first braided mesh component 121 and the second braided mesh component 122, the stiffness of the braided mesh 100 is denoted as K here, and the stiffness of the first braided mesh component 121 is denoted as k 1 , and the stiffness of the second braided mesh component 122 is denoted as k 2 , k 2 > k 1 , k 2 and k 1 satisfy the following relationship: . By changing the stiffness of the first braided mesh component 121 and the second braided mesh component 122, or by separately changing the stiffness of the first braided mesh component 121 or the second braided mesh component 122, the change of the overall stiffness of the braided mesh 100 can be achieved. The greater the overall stiffness of the braided mesh 100, the smaller the angle of occlusion between adjacent snake bone joints and the smaller the bending angle of the bending component.

[0053] In another embodiment of the present invention, Figure 9 Fig. 3 shows a schematic side view structure of a braided mesh provided by another embodiment of the present invention. As Figure 9 shown, the braided mesh unit 120 includes a first braided mesh component 121, a second braided mesh component 122, a third braided mesh component 123, and a fourth braided mesh component 124 connected in sequence. The first braided mesh component 121 is located at the front end of the braided mesh unit 120, and the fourth braided mesh component 124 is located at the rear end of the braided mesh unit 120. The stiffness of the first braided mesh component 121 is less than the stiffness of the second braided mesh component 122, the stiffness of the second braided mesh component 122 is less than the stiffness of the third braided mesh component 123, and the stiffness of the fourth braided mesh component 124 is equal to the stiffness of the second braided mesh component 122. This makes the stiffness of the braided mesh unit 120 show a four-stage change rule from weak to medium-strong, strong and then to medium-strong to meet the bending angle setting requirements of the passive bending part 500. By arranging a fourth braided mesh component 124 with medium-strong stiffness between the third braided mesh component 123 of the previous braided mesh unit 120 and the first braided mesh component 121 of the next braided mesh unit 120, the change of the stiffness of the braided mesh 100 can be made more gentle during the change from strong to weak, so as to enhance the bending state uniformity of the passive bending part 500.

[0054] It should be noted here that in this embodiment, the braided mesh unit 120 includes four braided mesh components. Of course, the number of braided mesh components is not limited to four, and can also be three, five or more.

[0055] In one embodiment of the present invention, the wire stiffness of the first braided mesh assembly 121 is less than that of the second braided mesh assembly 122, the wire stiffness of the second braided mesh assembly 122 is less than that of the third braided mesh assembly 123, and the wire stiffness of the fourth braided mesh assembly 124 is equal to that of the second braided mesh assembly 122.

[0056] It should be noted here that to achieve different stiffnesses of the four braided mesh assemblies, in addition to making the wire stiffnesses of the four braided mesh assemblies different, it can also be achieved by changing the braiding form of the braided mesh assemblies.

[0057] In one embodiment of the present invention, the length of the first braided mesh assembly 121 is greater than that of the second braided mesh assembly 122, the length of the second braided mesh assembly 122 is greater than that of the third braided mesh assembly 123, and the length of the fourth braided mesh assembly 124 is equal to that of the second braided mesh assembly 122. Of course, the length relationship of the above four braided mesh assemblies is not limited to this, and is specifically determined according to the length of the corresponding snake bone section and the length of the connection between two adjacent snake bone sections.

[0058] In a preferred embodiment of the present invention, the stiffness of the third braided mesh assembly 123 gradually increases in the direction from the front end side to the base end side of the insertion portion 300, that is, the stiffness of the third braided mesh assembly 123 gradually increases in the Figure 8 direction from left to right in the figure. By adopting such a setting method, the resilience of the passive bending portion 500 can be enhanced, and the bending state uniformity of the passive bending portion 500 can be enhanced.

[0059] Figure 10 Fig. 4 shows a schematic side view structure of a braided mesh provided by another embodiment of the present invention. As Figure 10 shown, in order to better understand the relationship between the stiffness of the braided mesh unit 120 and the stiffnesses of the four braided mesh assemblies, the stiffness of the braided mesh 100 is denoted as K here, and the stiffness of the first braided mesh assembly 121 is denoted as k 1 , the stiffnesses of the second braided mesh assembly 122 and the fourth braided mesh assembly 124 are denoted as k 2 , the stiffness of the third braided mesh assembly 123 is denoted as k 3 , k 3 >k 2 >k 1 , k 1、 k 2 and k 3 satisfy the following relationship: , ; By changing the stiffness of the first braided mesh component 121, the second braided mesh component 122, the third braided mesh component 123, and the fourth braided mesh component 124, or by changing the stiffness of the first braided mesh component 121, the second braided mesh component 122, the third braided mesh component 123, or the fourth braided mesh component 124 alone, the overall stiffness of the braided mesh 100 can be changed. The greater the overall stiffness of the braided mesh 100, the smaller the angle of engagement between adjacent snake bone joints, and the smaller the bending angle of the bending component.

[0060] In another embodiment of the present invention, the braided mesh 100 includes a plurality of sequentially connected braided mesh units 120, and the stiffness of each braided mesh unit 120 is equal, that is, the braided mesh 100 has a uniform stiffness, and the braided mesh 100 is in transitional fit with the snake bone assembly 110. Due to the transitional fit between the braided mesh 100 and the snake bone assembly 110, expansion deformation will occur between the braided mesh 100 and the snake bone assembly 110 due to the presence of the interference amount. The expansion deformation will cause the braided mesh 100 to form an elastic force, and the elastic force can make the braided mesh 100 have stronger rigidity.

[0061] The present invention also provides an endoscope, which includes a flexible portion 400, an active bending portion 600, and the endoscope passive bending portion 500 described in any one of the above. The flexible portion 400 is disposed on the proximal end side of the passive bending portion 500, the active bending portion 600 is disposed on the distal end side of the passive bending portion 500, and the bending radius of the passive bending portion 500 is greater than the bending radius of the active bending portion 600.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A passive bending portion of an endoscope, arranged at an insertion portion (300) of the endoscope, wherein the insertion portion (300) is inserted into a subject from a front end side along a longitudinal axis direction, characterized in that: The passive bending portion (500) comprises a snake bone component (110), and the snake bone component (110) comprises a plurality of snake bone segments hinged in sequence; The passive bending portion (500) further comprises a braided mesh (100), wherein the braided mesh (100) is sleeved on the outer peripheral surface of the snake bone component (110), and the braided mesh (100) comprises a plurality of braided mesh units (120) connected in sequence; When each of the braided mesh units (120) is bent to a maximum bending angle, the passive bending portion (500) reaches a maximum bending angle, and adjacent snake bone nodes are spaced apart.

2. The passive bending portion of the endoscope according to claim 1, characterized in that: The braided mesh (100) is formed by braiding a plurality of metal thin plates into a cylindrical metal tube, wherein the metal thin plates are formed by a plurality of metal wires (125) arranged in parallel.

3. The passive bending portion of the endoscope according to claim 2, characterized in that: When the passive bending portion (500) reaches the maximum bending angle, the outer edges of the metal sheets in the woven mesh unit (120) on the inner side along the bending direction of the woven mesh (100) abut against each other.

4. The passive bending portion of the endoscope according to claim 1, characterized in that: The rigidity of each braided mesh unit (120) is equal, and the braided mesh (100) and the snake bone component (110) are transitionally matched.

5. The passive bending portion of an endoscope according to any one of claims 1 to 3, characterized in that: The stiffness of the plurality of woven mesh units (120) varies periodically, wherein the stiffness of the woven mesh unit (120) sleeved on the periphery of the serpentine segment is smaller than the stiffness of the woven mesh unit (120) sleeved on the arc sections of two adjacent serpentine segments; the woven mesh unit (120) comprises at least two woven mesh components connected in sequence, and the stiffness of the woven mesh component with the largest stiffness gradually increases along the direction from the front end side to the base end side of the insertion portion (300).

6. The passive bending portion of the endoscope according to claim 5, characterized in that: The woven mesh unit (120) comprises a first woven mesh component (121) and a second woven mesh component (122) connected to the first woven mesh component (121), and the rigidity of the first woven mesh component (121) is smaller than the rigidity of the second woven mesh component (122).

7. The passive bending portion of the endoscope according to claim 6, characterized in that: The metal wire stiffness of the first woven mesh component (121) is smaller than the metal wire stiffness of the second woven mesh component (122).

8. The passive bending portion of the endoscope according to claim 6, characterized in that: The braiding angle of the first braided mesh component (121) is smaller than the braiding angle of the second braided mesh component (122).

9. The passive bending portion of the endoscope according to claim 5, characterized in that: The woven mesh unit (120) comprises a first woven mesh component (121), a second woven mesh component (122), a third woven mesh component (123), and a fourth woven mesh component (124) which are connected in sequence, the stiffness of the first woven mesh component (121) being smaller than the stiffness of the second woven mesh component (122), the stiffness of the second woven mesh component (122) being smaller than the stiffness of the third woven mesh component (123), and the stiffness of the fourth woven mesh component (124) being equal to the stiffness of the second woven mesh component (122).

10. An endoscope, characterized in that: include: The passive bending portion of an endoscope according to any one of claims 1 to 9; A flexible portion (400), the flexible portion (400) being arranged on the base end side of the passive bending portion (500); An active bending portion (600), the active bending portion (600) being arranged on the front end side of the passive bending portion (500); The bending radius of the passive bending portion (500) is greater than the bending radius of the active bending portion (600).

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