Vacuum suction sheath

Abstract

The present application belongs to the field of medical device technology, and specifically relates to a negative pressure suction sheath. The negative pressure suction sheath includes a sheath tube and a directional expansion structure. The sheath tube is arranged at the distal end of the negative pressure suction sheath. The distal end of the sheath tube has a passive bending section that can bend following the active bending section of the endoscope. The side wall of the passive bending section is provided with a through-hole, and the through-hole extends along the extension direction of the passive bending section. The directional expansion structure is connected to the sheath tube and seals the through-hole; when the passive bending section bends and squeezes the part of the directional expansion structure that seals the through-hole, the squeezed part of the directional expansion structure bulges toward the outside of the through-hole. The present application can solve the problem of unsmooth stone removal when the insertion part is used to drive the distal end of the sheath tube to bend to aspirate lateral stones.

Description

Technical Field

[0001] The present application belongs to the field of medical device technology, and specifically relates to a negative pressure suction sheath. Background Art

[0002] Negative pressure suction sheaths are often used in urological endoscopic examinations or surgeries. They can establish a surgical channel in the urinary system to assist the endoscope and surgical instruments in passing through the urethra, ureter and other cavities, thereby improving the effectiveness and safety of examinations and treatments.

[0003] When using a negative pressure suction sheath to remove kidney stones, the sheath of the negative pressure suction sheath can be placed into the kidney using a guide wire, and then the insertion portion of the endoscope can be inserted into the sheath to observe and break up the stones. When the stone is on the side of the sheath, the insertion portion can be used to drive the distal end of the sheath to bend, so that the sheath is directed toward the stone and the stone is sucked into the gap between the insertion portion and the sheath, thereby expelling the stone. However, in practice, when the insertion portion is used to drive the distal end of the sheath to bend to suck the lateral stone, the problem of unsmooth stone removal is prone to occur. Summary of the invention

[0004] The purpose of the present application is to provide a negative pressure suction sheath, which can solve the problem of unsmooth stone removal when the distal end of the sheath tube is bent by the insertion part to aspirate lateral stones.

[0005] In order to solve the above technical problems, this application is implemented as follows:

[0006] The present application provides a negative pressure suction sheath, comprising a sheath tube and a directional expansion structure, wherein the sheath tube is arranged at the distal end of the negative pressure suction sheath, the distal end of the sheath tube has a passive bending section that can bend following the active bending section of an endoscope, a through opening is arranged on the side wall of the passive bending section, the through opening extends along the extension direction of the passive bending section, and the directional expansion structure is connected to the sheath tube and seals the through opening;

[0007] When the passive bending section bends and presses the portion of the directional expansion structure that seals the through-opening, the pressed portion of the directional expansion structure bulges toward the outside of the through-opening.

[0008] The beneficial technical effects of this application are as follows:

[0009] In the present application, a through-hole is provided on the side wall of the passive bending section, and a directional expansion structure is connected to the sheath and seals the through-hole, thereby preventing the material to be sucked between the active bending section and the sheath from leaking from the through-hole to the outside of the sheath; when the negative pressure suction sheath of the present application is used, the insertion part of the endoscope can be inserted into the sheath, and when the active bending section drives the passive bending section to bend, the passive bending section will squeeze the part of the directional expansion structure that blocks the through-hole, so that the two ends of the part of the directional expansion structure are close to each other, so that the part of the directional expansion structure bulges toward the outside of the through-hole, which can increase the cross-sectional area of ​​the passive bending section at its own through-hole, thereby increasing the flow area at that place and increasing the minimum value of each maximum distance, so that the target object can smoothly pass through the gap between the curved active bending section and the curved passive bending section, thereby solving the problem of unsmooth discharge of stones waiting for suction.

[0010] In addition, when the passive bending section of the present application does not follow the active bending section to bend, the portion of the directional expansion structure located at the through-portion will not be squeezed, and thus the directional expansion structure will not bulge toward the outside of the through-portion. That is to say, when the passive bending section is in a straight state, the outer diameters of each portion of the passive bending section in its own extension direction are relatively small, which facilitates the insertion of the sheath into the human body. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the cooperation between the negative pressure suction sheath and the insertion part disclosed in the first embodiment of the present application;

[0012] Figure 2 An exploded view of the negative pressure suction sheath and the insertion part after being matched with each other according to the first embodiment of the present application;

[0013] Figure 3 A cross-sectional view of the negative pressure suction sheath and the insertion portion after being matched according to the first embodiment of the present application;

[0014] Figure 4 This is a schematic diagram of the cooperation between the negative pressure suction sheath and the insertion part disclosed in the second embodiment of the present application;

[0015] Figure 5 The explosion after the negative pressure suction sheath and the insertion part cooperate with each other is disclosed in the second embodiment of the present application. Figure 1 ;

[0016] Figure 6 An exploded view of the negative pressure suction sheath disclosed in the third embodiment of the present application;

[0017] Figure 7 The explosion of the negative pressure suction sheath disclosed in the second embodiment of the present application Figure 2 ;

[0018] Figure 8 An exploded view of the negative pressure suction sheath disclosed in the fourth embodiment of the present application;

[0019] Fig. 9 It is a schematic diagram of the cooperation between the curved sheath tube and the curved active bending section in the related art, and a schematic diagram of the cross section along the line a to the line g.

[0020] Description of reference numerals:

[0021] 100, sheath; 110, passive bending section; 111, through-port; 200, directional expansion structure; 210, occluding membrane; 300, insertion section; 310, active bending section. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0024] The negative pressure suction sheath provided in the embodiment of the present application is described in detail below through specific embodiments and their application scenarios in combination with the accompanying drawings.

[0025] In each embodiment of the present application, "proximal" and "distal" refer to the position of the negative pressure suction sheath and its components relative to the user in the use environment, wherein the end closer to the user is designated as the "proximal" and the end farther from the user is designated as the "distal".

[0026] like Fig. 9As shown, during the operation in which the insertion portion 300 and the sheath tube 100 are used together to remove stones and wait for the suction material, there is a suction gap between the endoscope insertion portion 300 and the inner wall of the sheath tube 100, so that the stones are discharged from the suction gap; of course, in order to facilitate the doctor to obtain the location of the stones, especially in the operation of kidney stone removal, the endoscope needs to be inserted into the renal calyx through the natural cavity or percutaneous kidney to remove stones in various areas of the renal calyx. Therefore, in order to avoid causing great trauma to the patient's kidneys, most endoscopes have a controllable bending function. Therefore, in order to adapt to the bending of the active bending section 310 of the endoscope insertion portion 300, the distal end of the sheath tube 100 adapted thereto in the prior art also has the ability of passive bending, that is, the active bending section 310 of the endoscope can drive the distal end of the sheath tube 100 to bend during the bending process.

[0027] The inventors discovered that, in actual surgical procedures, when the active bending section 310 drives the sheath tube 100 to be in a bent state, different parts of the active bending section 310 will press against specific positions of the sheath tube 100. Therefore, in the extension direction of the active bending section 310, the maximum distances between the various parts of the curved active bending section 310 in its own extension direction and the inner wall of the curved sheath tube 100 are unevenly distributed. In other words, the maximum distances between the various parts of the curved active bending section 310 in its own extension direction and the inner wall of the curved sheath tube 100 are constantly changing. Therefore, in the process of aspirating stones, stones whose size is equal to or slightly larger than the minimum value of the maximum distances may be blocked between the curved sheath tube 100 and the curved active bending section 310, resulting in poor stone removal.

[0028] Here, the maximum distance between each part of the curved active bending section 310 in its own extension direction and the inner wall of the curved sheath tube 100 is explained. Fig. 9 In views a to g, since the diameter of the active bending segment 310 is smaller than the diameter of the sheath tube 100, there must be a gap between the curved active bending segment 310 and the curved sheath tube 100, and the gap surrounds the curved active bending segment 310. Therefore, the distances between various circumferential regions of a part of the curved active bending segment 310 in its own extension direction and the inner wall of the sheath tube 100 are not equal, and the maximum value of the distances between various circumferential regions of this part of the curved active bending segment 310 and the sheath tube 100 is: the maximum distance between this part of the curved active bending segment 310 and the curved sheath tube 100.

[0029] like Figures 1 to 8As shown, the embodiment of the present application discloses a negative pressure suction sheath, including a sheath tube 100 and a directional expansion structure 200. The sheath tube 100 is arranged at the distal end of the negative pressure suction sheath, and the distal end of the sheath tube 100 has a passive bending section 110 that can bend following the active bending section 310 of the endoscope. Exemplarily, the endoscope here can be a bronchoscope, a pyeloscope, an esophagoscope, a gastroscope, an enteroscope, an otoscope, a rhinoscope, a stomatoscope, a laryngoscope, a colposcope, a laparoscope, an arthroscope, etc., and the embodiment of the present application does not specifically limit the type of the endoscope.

[0030] The side wall of the passive bending section 110 is provided with a through hole 111, wherein the through hole 111 here penetrates from the outer circumference of the passive bending section 110 to the inner circumference of the passive bending section 110, and the through hole 111 extends along the extension direction of the passive bending section 110, and the directional expansion structure 200 is connected to the sheath tube 100 and seals the through hole 111. Specifically, the directional expansion structure 200 here covers and seals the through hole 111, thereby preventing the material to be sucked between the active bending section 310 and the sheath tube 100 from leaking from the through hole 111 to the outside of the sheath tube 100.

[0031] When the passive bending section 110 bends and presses the portion of the directional expansion structure 200 that seals the through-hole 111, the pressed portion of the directional expansion structure 200 bulges toward the outside of the through-hole 111. Figure 1 When the passive bending section 110 bends following the active bending section 310, the portion of the through opening 111 located on the extrusion side of the passive bending section 110 will adapt to the bending of the passive bending section 110. Therefore, the distance between the two ends of the through opening 111 along the extension direction of the passive bending section 110 will decrease, which will cause the portion of the directional expansion structure 200 covering the through opening 111 to be squeezed, and the directional expansion structure 200 will deform when subjected to the squeezing force, thereby expanding and bulging outward. The outward here refers to the outer side of the portion of the directional expansion structure 200 covering the through opening 111 away from the through opening 111.

[0032] In the present application, the side wall of the passive bending section 110 is provided with a through hole 111, and the directional expansion structure 200 is connected to the sheath tube 100 and seals the through hole 111, so that the suction material between the active bending section 310 and the sheath tube 100 can be prevented from leaking from the through hole 111 to the outside of the sheath tube 100; when the negative pressure suction sheath of the present application is applied, the insertion part 300 of the endoscope can be inserted into the sheath tube 100, and when the active bending section 310 drives the passive bending section 110 to bend, the passive bending section 110 will squeeze the directional expansion structure 200 to block the through hole 111. Part, so that the two ends of the part of the directional expansion structure 200 are close to each other, so that the part of the directional expansion structure 200 bulges toward the outside of the through-opening 111, which can increase the cross-sectional area of ​​the passive bending section 110 at its own through-opening 111, thereby increasing the flow area there and increasing the minimum value of each maximum distance, so that the target object (the stone stuck in the related technology) can smoothly pass through the gap between the curved active bending section 310 and the curved passive bending section 110, thereby solving the problem of unsmooth discharge of stones while waiting for suction.

[0033] In addition, when the passive bending section 110 of the present application does not follow the active bending section 310 to bend, the portion of the directional expansion structure 200 located at the through-opening 111 will not be squeezed, and thus the directional expansion structure 200 will not bulge toward the outside of the through-opening 111. That is to say, when the passive bending section 110 is in a straight state, the outer diameters of various portions of the passive bending section 110 in its own extension direction are relatively small, which facilitates the insertion of the sheath 100 into the human body.

[0034] The operation methods of using the negative pressure suction sheath of the present application to solve the problem of unsmooth discharge of stones while waiting for the suctioned material include the following two methods:

[0035] 1. After the insertion portion 300 of the endoscope is inserted into the sheath tube 100 and the active bending section 310 drives the sheath tube 100 to bend, the raised directional expansion structure 200 corresponds to the minimum value of each maximum distance of the sheath tube 100 in the prior art. That is to say, after the active bending section 310 is inserted into the sheath tube 100 and drives the sheath tube 100 to bend, the minimum value of each maximum distance is greater than the size of the target object, so that the target object can smoothly pass through the gap between the bent active bending section 310 and the inner wall of the tube section of the sheath tube 100 bent by the active bending section 310, thereby solving the problem of unsmooth discharge of stones while waiting for suction.

[0036] 2. After the insertion portion 300 of the endoscope is inserted into the sheath 100 and the active bending section 310 drives the sheath 100 to bend, the raised directional expansion structure 200 does not correspond to the minimum value of each maximum distance of the sheath 100 in the prior art. For example, the raised directional expansion structure 200 is located proximal to the minimum value of each maximum distance of the sheath 100. At this time, it is only necessary to pull the active bending section 310 to move the active bending section 310 toward the proximal end until a part of the bent active bending section 310 enters the raised directional expansion structure 200, so that the minimum value of each maximum distance is greater than the size of the target object by utilizing the raised directional expansion structure 200, thereby introducing the target object stuck between the bent sheath 100 and the bent active bending section 310 into the raised directional expansion structure 200, so as to solve the problem of the target object being stuck between the bent sheath 100 and the bent active bending section 310.

[0037] In order to prevent the directional expansion structure 200 from collapsing toward the inside of the passive bending section 110 when being squeezed, and the directional expansion structure 200 cannot bulge toward the outside of the through-opening 111 when collapsing inward, so that the stones waiting to be sucked may not be able to pass smoothly through the gap between the curved active bending section 310 and the curved passive bending section 110, in an optional embodiment, the directional expansion structure 200 includes a sealing membrane 210 and a braided layer (not shown in the figure), and the sealing membrane 210 is connected to the braided layer. When the passive bending section 110 bends and squeezes the part of the directional expansion structure 200 that seals the through-opening 111, the squeezed part of the braided layer bulges toward the outside of the through-opening 111.

[0038] In this embodiment, the directional expansion structure 200 includes a blocking film 210 and a braided layer, which can make the directional expansion structure 200 have a certain rigidity and toughness, so that the directional expansion structure 200 is not easy to collapse toward the inside of the passive bending section 110 when subjected to extrusion force, but is more likely to bulge toward the outside of the through-hole 111, that is, after adopting the structure of this embodiment, the directional expansion structure 200 can stably bulge toward the outside of the through-hole 111, which is more conducive to solving the problem of unsmooth discharge of stones and waiting for suction. Of course, the directional expansion structure 200 here can also only include the blocking film 210, and this application is not limited to this.

[0039] In an optional embodiment, the braided layer includes a first part and a second part, the first part covers the middle part of the through-opening 111 along the extension direction of the passive bending section 110, the second part covers the other parts of the through-opening 111, and the stiffness of the first part is greater than the stiffness of the second part. Specifically, the second part may include a first sub-part and a second sub-part, the first sub-part and the second sub-part are respectively located on both sides of the first part and are respectively connected to the first part, and the stiffness of the first sub-part and the second sub-part are both less than the stiffness of the first part.

[0040] In this embodiment, since the stiffness of the second part is smaller and the stiffness of the first part is larger, when the passive bending section 110 is bent, this stiffness difference will cause the stress to be unevenly distributed in the contact area between the braided layer and the passive bending section 110, so that the stress is concentrated in the middle of the braided layer, while the stress is relatively dispersed on both sides of the braided layer. This uneven stress distribution will push the middle part of the braided layer outward when the braided layer is bent, making it easier for the braided layer to bulge. Of course, the stiffness of the first part can also be less than or equal to the stiffness of the second part, and this application does not limit this.

[0041] In an optional embodiment, the braiding density of the first part is greater than the braiding density of the second part. This embodiment achieves the purpose of making the stiffness of the first part greater than the stiffness of the second part by setting different braiding densities, which is more conducive to processing the braided layer. Of course, the purpose of making the stiffness of the first part greater than the stiffness of the second part can also be achieved by setting different braiding diameters or different braiding materials.

[0042] See also Figure 8 In an optional embodiment, when the passive bending section 110 is in a straight state, the portion of the directional expansion structure 200 that seals the through-opening 111 pre-bulges toward the outside of the through-opening 111; when the passive bending section 110 bends and squeezes the pre-bulged portion of the directional expansion structure 200, the pre-bulged portion of the directional expansion structure 200 bulges toward the outside of the through-opening 111.

[0043] In the present embodiment, the directional expansion structure 200 is initially pre-bulged outward, that is, the directional expansion structure 200 has a certain tendency to expand outward when not subject to external force, which makes the outer side of the directional expansion structure 200 have a higher initial curvature. In this way, when the directional expansion structure 200 is subjected to an extrusion force, the pre-bulged structure can better adapt to the bending deformation of the passive bending section 110, thereby making it easier for the directional expansion structure 200 to expand and bulge outward.

[0044] See also Figure 2 In an optional embodiment, along the extension direction of the passive bending section 110 , the depth of the through opening 111 first gradually increases and then gradually decreases, and the portion with the largest depth of the through opening 111 is located in the middle of the through opening 111 along the extension direction of the passive bending section 110 .

[0045] In this embodiment, the depth of the middle part of the through-opening 111 along the extension direction of the passive bending section 110 is larger, and the depth of the two sides is smaller, which can make the part of the passive bending section 110 opposite to the middle part of the through-opening 111 have less solid material remaining, and the part of the passive bending section 110 opposite to the two sides of the through-opening 111 have more solid material remaining, that is, the cross-sectional area and rigidity of the part of the passive bending section 110 opposite to the middle part of the through-opening 111 are smaller, so that when the passive bending section 110 is subjected to the bending moment applied by the active bending section 310, the part of the passive bending section 110 opposite to the middle part of the through-opening 111 is more likely to deform, and the degree of deformation is greater, which can make the two ends of the passive bending section 110 and the parts opposite to the two sides of the through-opening 111 closer together, thereby increasing the squeezing force on the directional expansion structure 200, so as to increase the bulge of the directional expansion structure 200, thereby further improving the smoothness of the discharge of stones waiting to be sucked.

[0046] And / or, in an optional embodiment, the directional expansion structure 200 is an annular structure, and the directional expansion structure 200 is sleeved outside the passive bending section 110. In this embodiment, the directional expansion structure 200 is annular, which can increase the connection area between the directional expansion structure 200 and the passive bending section 110, thereby improving the connection stability between the directional expansion structure 200 and the passive bending section 110. Of course, the directional expansion structure 200 may not be annular, but may be sheet-shaped, and this application is not limited to this.

[0047] Please continue reading Figure 2 In an optional embodiment, the number of the through opening 111 is one, and the maximum depth of the through opening 111 is greater than half of the outer diameter of the passive bending section 110 .

[0048] In this embodiment, the maximum depth of the through-opening 111 is greater than half of the outer diameter of the passive bending section 110, which can make the remaining solid material of the passive bending section 110 and the part opposite to the middle part of the through-opening 111 less and the rigidity smaller. In this way, when the passive bending section 110 is subjected to the bending moment applied by the active bending section 310, the deformation degree of the passive bending section 110 and the part opposite to the middle part of the through-opening 111 will be further increased, which can further reduce the distance between the two ends of the passive bending section 110 and the parts opposite to each other on both sides of the through-opening 111, thereby further increasing the squeezing force on the directional expansion structure 200, so as to further increase the bulge of the directional expansion structure 200, thereby further improving the smoothness of the discharge of stones and the material waiting to be aspirated.

[0049] See also Figure 5 and Figure 7 In an optional embodiment, the number of the through openings 111 is two, and the two through openings 111 are respectively located on opposite sides of the passive bending section 110 , and the directional expansion structure 200 seals each through opening 111 .

[0050] Generally speaking, the active bending section 310 of the endoscope has a bidirectional bending function. If only one through-hole 111 is provided, and when the passive bending section 110 bends following the active bending section 310, if the through-hole 111 is located just on the stretching side of the passive bending section 110, the directional expansion structure 200 will not bulge toward the outside of the through-hole 111. In order to enable the negative pressure suction sheath of the present application to adapt to the bidirectional bending of the active bending section 310, the present embodiment provides through-holes 111 on opposite sides of the passive bending section 110, and the directional expansion structure 200 seals each through-hole 111. In this way, no matter which direction the active bending section 310 bends in, there is always a through-hole 111 located on the extrusion side of the passive bending section 110, so that the portion of the directional expansion structure 200 that blocks the corresponding through-hole 111 expands and bulges in a direction away from the through-hole 111. It can be seen that after adopting the structure of this embodiment, no matter in which direction the active bending section 310 bends, the directional expansion structure 200 can expand and bulge in that direction. In other words, no matter in which direction the active bending section 310 bends, when the negative pressure suction sheath is used to aspirate the stones, the stones will not be stuck between the active bending section 310 and the passive bending section 110.

[0051] Please continue reading Figure 5 In an optional embodiment, along the extension direction of the passive bending section 110 , the depth of each through opening 111 first gradually increases and then gradually decreases, and the deepest part of each through opening 111 is located in the middle of the corresponding through opening 111 along the extension direction of the passive bending section 110 .

[0052] In the present embodiment, the depth of the middle part of each through-hole 111 along the extension direction of the passive bending section 110 is larger, and the depth on both sides is smaller, which can make the part of the passive bending section 110 opposite to the middle part of the through-hole 111 have less solid material remaining, that is, the cross-sectional area and stiffness of the part of the passive bending section 110 opposite to the middle part of the through-hole 111 are smaller, so that when the passive bending section 110 is subjected to the bending moment applied by the active bending section 310, the part of the passive bending section 110 opposite to the middle part of the through-hole 111 is more likely to deform, and the degree of deformation is greater, which can make the two ends of the passive bending section 110 and the parts opposite to the two sides of the through-hole 111 closer to each other, thereby increasing the squeezing force on the directional expansion structure 200, so as to increase the degree of bulging of the directional expansion structure 200, thereby further improving the smoothness of the discharge of stones waiting to be aspirated.

[0053] In a further embodiment, the maximum depth of each through hole 111 is less than half of the outer diameter of the passive bending section 110, and the sum of the maximum depths of the two through holes 111 is greater than half of the outer diameter of the passive bending section 110, which can make the remaining solid material of the passive bending section 110 and the part opposite to the middle part of the through hole 111 less and the rigidity smaller. In this way, when the passive bending section 110 is subjected to the bending moment applied by the active bending section 310, the degree of deformation of the passive bending section 110 and the part opposite to the middle part of the through hole 111 will be further increased, which can further reduce the distance between the two ends of the passive bending section 110 and the parts opposite to each other on both sides of the through hole 111, thereby further increasing the squeezing force on the directional expansion structure 200, so as to further increase the bulge of the directional expansion structure 200, thereby further improving the smoothness of the discharge of stones waiting to be aspirated.

[0054] See also Figure 6 In an optional embodiment, the number of through-holes 111 includes at least three, and at least three through-holes 111 are evenly spaced along the circumference of the passive bending section 110, and the directional expansion structure 200 seals each through-hole 111. In this embodiment, at least three through-holes 111 are evenly spaced along the circumference of the passive bending section 110, so that even if the active bending section 310 has more than two bending directions, after adopting the structure of this embodiment, no matter which direction the active bending section 310 bends, the directional expansion structure 200 can expand and bulge, that is, no matter which direction the active bending section 310 bends, when the negative pressure suction sheath is used to aspirate the stone, the stone will not be stuck between the active bending section 310 and the passive bending section 110.

[0055] The above embodiments of the present application focus on the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, they will not be repeated here. The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present application, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present application and the claims, all of which are within the protection of the present application.

Claims

1. A negative pressure suction sheath, characterized in that: The invention comprises a sheath tube (100) and a directional expansion structure (200), wherein the sheath tube (100) is arranged at the distal end of the negative pressure suction sheath, the distal end of the sheath tube (100) has a passive bending section (110) capable of bending following the active bending section (310) of the endoscope, the side wall of the passive bending section (110) is provided with a through opening (111), the through opening (111) extends along the extension direction of the passive bending section (110), and the directional expansion structure (200) is connected to the sheath tube (100) and seals the through opening (111); When the passive bending section (110) bends and squeezes the portion of the directional expansion structure (200) that seals the through-opening (111), the squeezed portion of the directional expansion structure (200) bulges toward the outside of the through-opening (111).

2. The negative pressure suction sheath according to claim 1, characterized in that: The directional expansion structure (200) comprises a blocking membrane (210) and a braided layer, wherein the blocking membrane (210) is connected to the braided layer, and when the passive bending section (110) bends and squeezes the portion of the directional expansion structure (200) that seals the through-opening (111), the squeezed portion of the braided layer bulges toward the outside of the through-opening (111).

3. The negative pressure suction sheath according to claim 2, characterized in that: The braided layer comprises a first part and a second part, the first part covers the middle part of the through opening (111) in the extension direction of the passive bending section (110), and the second part covers the other parts of the through opening (111), and the stiffness of the first part is greater than that of the second part.

4. The negative pressure suction sheath according to claim 3, characterized in that: The braiding density of the first portion is greater than the braiding density of the second portion.

5. The negative pressure suction sheath according to claim 1, characterized in that: When the passive bending section (110) is in a straightened state, the portion of the directional expansion structure (200) that seals the through-opening (111) pre-bulges toward the outside of the through-opening (111); When the passive bending section (110) bends and presses the pre-bulged portion of the directional expansion structure (200), the pre-bulged portion of the directional expansion structure (200) bulges toward the outside of the through opening (111).

6. The negative pressure suction sheath according to claim 1, characterized in that: Along the extension direction of the passive bending section (110), the depth of the through opening (111) first gradually increases and then gradually decreases, and the portion of the through opening (111) with the largest depth is located in the middle of the through opening (111) along the extension direction of the passive bending section (110); And / or, the directional expansion structure (200) is an annular structure, and the directional expansion structure (200) is sleeved outside the passive bending section (110).

7. The negative pressure suction sheath according to claim 6, characterized in that: The number of the through opening (111) is one, and the maximum depth of the through opening (111) is greater than half of the outer diameter of the passive bending section (110).

8. The negative pressure suction sheath according to claim 1, characterized in that: The number of the through openings (111) is two, and the two through openings (111) are respectively located on opposite sides of the passive bending section (110), and the directional expansion structure (200) seals each of the through openings (111).

9. The negative pressure suction sheath according to claim 8, characterized in that: Along the extension direction of the passive bending section (110), the depth of each through opening (111) first gradually increases and then gradually decreases, and the portion with the largest depth of each through opening (111) is located in the middle of the corresponding through opening (111) along the extension direction of the passive bending section (110); The maximum depth of each through opening (111) is less than half of the outer diameter of the passive bending section (110), and the sum of the maximum depths of the two through openings (111) is greater than half of the outer diameter of the passive bending section (110).

10. The negative pressure suction sheath according to claim 1, characterized in that: The number of the through openings (111) includes at least three, and the at least three through openings (111) are evenly spaced and distributed along the circumference of the passive bending section (110), and the directional expansion structure (200) seals each of the through openings (111).

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