A tissue cutting device

Abstract

This utility model discloses a tissue cutting device, including a cutting electrode and a sheath. The distal end of the sheath has an insulated end tube. The cutting electrode is axially movably inserted into the end tube. The device also includes a limiting component, disposed between the end tube and the sheath to limit axial displacement between them, and having an integrally or separately disposed fixing member and a snap-fit ​​member. The fixing member is used to fix the end tube and the sheath; the snap-fit ​​member is used to fix the fixing member and the end tube or the sheath and the end tube. The limiting component between the sheath and the end tube forms a fixed connection between them, limiting the axial displacement of the end tube relative to the sheath and enhancing the sealing effect on the electrode. With this configuration, the electrode, ceramic tube, and sheath remain stably connected during axial movement of the cutting electrode, preventing loosening and ensuring both the effectiveness and safety of the cutting.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically to a tissue cutting device. Background Technology

[0002] Under the endoscopic view of the digestive tract, the high-frequency electrosurgical unit, which serves as a tissue cutting device, outputs high-frequency electricity from the electrode to act on the mucosal tissue, causing the mucosal tissue cells to vaporize or lose water, marking or cutting the tissue. Liquid flows out from the distal end of the electrode of the high-frequency electrosurgical unit, causing the tissue to bulge, separating the tissue to be removed from the muscle layer, making it easier to cut.

[0003] However, the sheath material commonly used in digestive endoscopy instruments is Teflon. Due to its high lubricity and stable chemical properties, Teflon sheaths are difficult to connect with other parts and cannot be stably connected through conventional bonding, heat fusion, or other processes.

[0004] Therefore, during the use of a high-frequency electrosurgical unit, unstable connections between the sheath and other components can easily lead to loosening and detachment of the electrode, ceramic tube, and sheath during axial electrode movement, affecting the cutting effect and safety. Simultaneously, when the high-frequency electrosurgical unit has fluid injection and flushing functions, loosening of the sheath and other components can also affect the electrode's sealing, causing fluid to leak out from other channels. Utility Model Content

[0005] Therefore, this invention aims to solve the problem in the prior art where unstable connection between the sheath and other parts of the electrosurgical unit can cause the high-frequency electrosurgical unit to loosen during use, affecting the cutting effect and safety, thereby providing a tissue cutting device.

[0006] To solve the above-mentioned technical problems, the technical solution of this utility model is as follows:

[0007] This utility model provides a tissue cutting device, including a blade electrode and a sheath. The distal end of the sheath is provided with an insulating end tube. The blade electrode is axially movable and passes through the end tube. It also includes a limiting component, which is disposed between the end tube and the sheath to limit the axial displacement between the two, and has an integral or separate fixing component and a snap-fit ​​component.

[0008] The fastener is used to secure the end tube and the sheath; the snap-fit ​​is used to secure the fastener and the end tube or the sheath and the end tube. The fastener and snap-fit ​​form a fixed connection between the end tube and the sheath to limit the axial displacement of the end tube relative to the sheath.

[0009] Furthermore, the proximal end of the fastener is provided with a radially outwardly extending barb structure, which is embedded in the inner wall of the sheath to restrict the axial displacement of the fastener relative to the sheath; the distal end of the fastener is provided with an axially extending fixing tube. The fixing tube may be elastic or rigid.

[0010] Furthermore, the outer wall of the end tube is provided with a fastening part near the end, and the fastening part forms a fixing groove with the far end of the fixing tube;

[0011] The at least one snap-fit ​​element is accommodated in the fixing groove and snaps into the fastening portion to connect the end tube to the fixing element.

[0012] Furthermore, the snap-fit ​​component is a C-shaped ring, which is fixed to the distal end of the fixing tube and forms a boss; the boss is accommodated in the fixing groove and snaps into the fastening part.

[0013] Furthermore, the snap-fit ​​component is integrally connected to the fixing tube and located at the distal end of the fixing tube. The snap-fit ​​component includes at least one elastic buckle. The elastic buckle is at least partially accommodated in the fixing groove and snapped into the fastening part.

[0014] Furthermore, the snap-fit ​​component includes a radially inwardly extending barb structure disposed on the inner wall of the end tube, the barb structure being embedded in the outer wall of the sheath to restrict axial displacement of the end tube relative to the sheath.

[0015] Furthermore, the tissue cutting device also includes a sealing structure, which includes a sealing element and a sealing groove; the sealing groove is disposed inside the end tube or inside the fixing element; the sealing element is accommodated in the sealing groove to achieve a seal on the outside of the cutting electrode.

[0016] Furthermore, the sealing groove is disposed within the fixing member, and the sealing member is disposed within the sealing groove and sleeved on the cutting electrode; wherein, the fixing member is sleeved outside the sealing member, the end tube and the fixing member confine the sealing member within the sealing groove inside the fixing member, and the sheath tube applies a force to the fixing member to compress the sealing member.

[0017] Furthermore, the sealing groove is disposed inside the end tube, and the sealing element is disposed inside the sealing groove and sleeved on the cutter electrode; wherein, the end tube is sleeved outside the sealing element, and the sealing element is restricted inside the end tube by the end tube and the fixing element, and the sheath tube applies a force to the end tube to compress the sealing element.

[0018] Furthermore, the end tube has a through groove extending along the length direction, and a groove is provided at the distal end of the through groove. A cutter disc is provided on the cutter electrode. When the cutter electrode is retracted to its maximum extent toward the proximal end of the sheath, the cutter disc is located in the groove, and the cutter electrode is at least partially exposed in the end tube.

[0019] Furthermore, the tissue cutting device also includes a connecting tube with a limiting boss. When the cutting electrode is fully extended, the limiting boss abuts against the proximal end of the fixing member to limit the maximum extension position of the cutting electrode.

[0020] Furthermore, the distal portion of the sheath has a variable diameter section, the outer diameter of which is larger than the rest of the sheath. The outer surface of the variable diameter section of the sheath is marked and located close to the end tube along the circumferential direction of the sheath; or / and, a marking ring is provided at the distal end of the variable diameter section of the sheath.

[0021] Furthermore, the tissue cutting device also includes an operating part, which includes an operating handle, an injection handle, a connector, and a finger ring, with the connector mounted on the finger ring; a protective tube is provided outside the sheath, and the proximal end of the sheath is connected to the distal end of the injection handle via barbs; a connecting tube and a torque wire are provided near the proximal end of the blade electrode, one end of the connecting tube is connected to the blade electrode, and the other end is electrically connected to the connector by welding to the torque wire; a push-pull rod is provided outside the torque wire, and the proximal end of the injection handle and the distal end of the handle are connected by a snap-fit; a sealing ring is provided between the handle and the injection handle, and a gasket is provided at the rear end of the sealing ring and abuts against the front end of the handle to apply a pressing force to the push-pull rod and the injection handle; one end of the push-pull rod passes through the gasket and the sealing ring, and the other end of the push-pull rod is fixed to the torque wire and the connector at the end face.

[0022] The technical solution of this utility model has the following advantages:

[0023] The tissue cutting device provided by this utility model has a limiting component between the sheath and the end tube, so that the end tube and the sheath are fixedly connected to limit the axial displacement of the end tube relative to the sheath and at the same time enhance the sealing effect on the electrode. With this setting, the connection strength between the electrode, ceramic tube and sheath is high during the axial movement of the cutting electrode, so as to achieve a stable connection and prevent loosening, thus ensuring the cutting effect and safety. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the distal portion of the tissue cutting device in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the retracted state of the blade electrode in the tissue cutting device in an embodiment of the present invention;

[0027] Figure 3 This is a cross-sectional view of the extended state of the blade electrode in the tissue cutting device of Embodiment 1 of this utility model;

[0028] Figure 4 This is a cross-sectional view of the retracted state of the blade electrode in the tissue cutting device of Embodiment 1 of this utility model;

[0029] Figure 5 This is a schematic diagram of the distal portion of the tissue cutting device in Embodiment 2 of this utility model;

[0030] Figure 6 This is a cross-sectional view of the retracted state of the blade electrode in the tissue cutting device of Embodiment 2 of this utility model;

[0031] Figure 7 This is a cross-sectional view of the retracted state of the blade electrode in the tissue cutting device of Embodiment 2 of this utility model;

[0032] Figure 8 This is a schematic diagram of the distal portion of the tissue cutting device in Embodiment 3 of this utility model;

[0033] Figure 9 This is a cross-sectional view of the tissue cutting device in Embodiment 3 of this utility model with the electrode of the cutting head extended.

[0034] Figure 10 This is a cross-sectional view of the tissue cutting device in Embodiment 3 of this utility model with the electrode of the cutting head extended.

[0035] Figure 11 This is a cross-sectional view of the tissue cutting device in Embodiment 4 of this utility model with the cutting electrode extended.

[0036] Figure 12 This is a cross-sectional view of the retracted electrode of the tissue cutting device in Embodiment 4 of this utility model;

[0037] Figure 13 This is a cross-sectional view of the tissue cutting device in Embodiment 5 of this utility model with the blade electrode extended.

[0038] Figure 14 This is a cross-sectional view of the retracted electrode of the tissue cutting device in Embodiment 5 of this utility model;

[0039] Figure 15 This is a schematic diagram and a partially enlarged schematic diagram of the handle of the tissue cutting device in this patent embodiment.

[0040] Explanation of reference numerals in the attached figures:

[0041] 1. Cutter head electrode; 1-1. Cutter head disc; 2. End tube; 2-3. Groove; 3. Sheath; 3-1. Marker; 3-2. Variable diameter section; 4. Fixing component; 4-1. Fixing tube; 4-2. Barbed structure; 5. Connecting tube; 5-1. Limiting boss; 6. Torque wire; 7. C-ring; 8. Seal; 8-1. Sealing groove; 9. Elastic buckle; 10. Fastening part; 10-1. Fixing groove; 11. Marking ring; 12. Barbed structure; 13. Limiting boss; 14. Protective tube; 15. Injection handle; 16. Push-pull rod; 17. Gasket; 18. Sealing ring; 19. Handle; 20. Finger ring; 21. Connector. Detailed Implementation

[0042] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0043] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0045] In the embodiments of this specification, "proximal" and "distal" can refer to directions, with the side facing the operator being the "proximal" and the side facing the insertion into the body for treatment being the "distal". "Proximal" and "distal" can also refer to the part of the structure and the end located in the corresponding direction.

[0046] In the embodiments of this specification, "axial" and "radial" can refer to directions. For example, the axial direction of the protective electrode refers to the direction along the center line or rotation axis of the protective electrode, and the "radial" direction is perpendicular to the "axial" direction.

[0047] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0048] This utility model provides a tissue cutting device, including a blade electrode 1 and a sheath 3; the distal end of the sheath 3 is provided with an insulating end tube 2, and the blade electrode 1 is axially movable and passes through the end tube 2.

[0049] The blade electrode 1 can be a needle knife, hook knife, IT knife, etc. The sheath is made of Teflon, and the end tube is made of insulating material, including but not limited to ceramic, zirconium oxide, alumina, etc., or metal tubes with insulating sleeves or insulating coatings.

[0050] The distal end of the sheath 3 is provided with an insulating end tube, including but not limited to: the end tube being disposed at the distal end of the outer wall of the sheath, with at least a portion of the proximal end of the end tube being contained within the sheath; or the sheath being sleeved over the end tube, with at least a portion of the distal end of the end tube protruding from the distal end of the sheath; or the end tube being sleeved over the sheath, with at least a portion of the sheath being contained within the end tube.

[0051] It also includes: a limiting component, which is disposed between the end tube and the sheath to limit the axial displacement between the two, and has an integral or separate fixing member and a snap-fit ​​member; the fixing member is used to fix the end tube and the sheath; the snap-fit ​​member is used to fix the fixing member and the end tube or the sheath and the end tube.

[0052] The fixing and snap-fit ​​components in the limiting component can be integrally formed or set separately; similarly, the limiting component can be integrally formed with the end tube or set separately.

[0053] The tissue cutting device provided by this utility model has a limiting component between the sheath and the end tube, so that the end tube and the sheath are fixedly connected to limit the axial displacement of the end tube relative to the sheath and at the same time enhance the sealing effect of the electrode. With this configuration, the electrode, ceramic tube and sheath are stably connected during the axial movement of the cutting electrode, and will not loosen, thus ensuring the cutting effect and safety.

[0054] Example 1:

[0055] like Figures 1-4 As shown, the end tube is located at the distal end of the outer wall of the sheath, and the proximal end of the end tube is at least partially contained within the sheath. The outer diameter of the proximal end of the end tube is smaller than the inner diameter of the distal diameter-changing section of the sheath.

[0056] In this embodiment, the fastener is an independent component and is located near the end of the end tube. The material of the fastener as a whole includes, but is not limited to, metal materials such as stainless steel.

[0057] The proximal end of the fastener 4 is provided with a radially outwardly extending barb structure 4-2, which is embedded in the inner wall of the sheath tube 3 to limit the axial displacement of the fastener 4 relative to the sheath tube 3; the distal end of the fastener 4 is provided with an axially extending fixing tube 4-1. In this embodiment, the fixing tube 4-1 is made of rigid material, and the barb structure in this embodiment is made of metal.

[0058] The end tube 2 has a fastening part 10 near the outer wall. The fastening part 10 and the inner wall of the far end of the fixing tube 4-1 form a fixing groove 10-1. At least one snap-fit ​​member is accommodated in the fixing groove 10-1 and snaps into the fastening part 10 so that the end tube 2 is connected to the fixing member 4.

[0059] In this embodiment, the snap-fit ​​component can be set as an independent C-ring, the material of which includes, but is not limited to, metal. The C-ring 7 can be welded and fixed to the distal inner wall of the fixing tube 4-1, forming a boss; the boss is accommodated in the fixing groove 10-1 and snapped onto the fastening part 10, that is, the C-ring is welded to the fixing tube, and the boss formed by the C-ring and the fixing tube is hooked onto the fastening part near the end of the end tube. The end tube is connected to the fixing tube through the C-ring, and at the same time, the barb structure at the distal end of the fixing component is embedded in the inner wall of the sheath, realizing the fixed connection between the end tube and the sheath. Since the fixing component is made of metal, the connection force of the barb structure embedded in the inner wall is greater. The combination of the C-ring and the barb structure makes the connection force between the sheath and the end tube greater, avoiding the loosening of instrument parts during the axial movement of the blade electrode, which would affect the cutting effect and safety.

[0060] Example 2:

[0061] like Figures 5 to 7 As shown, the end tube is located at the distal end of the outer wall of the sheath, and the proximal end of the end tube is at least partially accommodated within the sheath. The outer diameter of the proximal end of the end tube is smaller than the inner diameter of the diameter-changing section at the distal end of the sheath. In this embodiment, the fixing member is an independent component and is located at the proximal end of the end tube.

[0062] The snap-fit ​​component is integrally connected to the fixing tube and located at the far end of the fixing tube 4-1. The snap-fit ​​component includes at least one elastic buckle 9. The elastic buckle 9 is at least partially accommodated in the fixing groove 10-1 and snapped into the fastening part 10.

[0063] The proximal end of the fastener 4 is provided with a radially outwardly extending barb structure 4-2, which is embedded in the inner wall of the sheath tube 3 to limit the axial displacement of the fastener 4 relative to the sheath tube 3; the distal end of the fastener 4 is provided with an axially extending fixing tube 4-1.

[0064] The fixing tube in this embodiment is elastic and can be designed as an elastic structure with gaps. The fixing tube 4-1 of the fixing member is provided with an elastic buckle 9 to form an internal boss. The buckle 9 is elastic. During the assembly process, after the outer wall of the far end of the end tube is squeezed to make the inner diameter of the fixing tube larger, the buckle 9 is snapped into the fixing groove 10-1 to fix the fixing member 4 and the end tube 2.

[0065] The elastic buckle engages with the latching part at the proximal end of the end tube, which in turn connects to the fixing tube via the elastic buckle. Simultaneously, the barbed structure at the distal end of the fixing component embeds into the inner wall of the sheath, achieving a secure connection between the end tube and the sheath. This combination of the elastic buckle and barbed structure increases the connection force between the sheath and the end tube, preventing the instrument parts from loosening during the axial movement of the cutting electrode, thus ensuring the cutting effect and safety.

[0066] Example 3:

[0067] like Figures 8-10 As shown, in this embodiment, the end tube is located at the distal end of the outer wall of the sheath, and the end tube is sleeved outside the sheath, with at least a portion of the sheath housed within the end tube. In this embodiment, the fixing component is an independent part. The material of the fixing component as a whole includes, but is not limited to, metal materials such as stainless steel.

[0068] The snap-fit ​​component has a radially inwardly extending barb structure 12 disposed on the inner wall of the end tube, the barb structure 2-1 being embedded in the outer wall of the sheath tube 3 to limit the axial displacement of the end tube 2 relative to the sheath tube 3.

[0069] The proximal end of the fastener 4 is provided with a radially outwardly extending barb structure 4-2, which is embedded in the inner wall of the sheath tube 3 to limit the axial displacement of the fastener 4 relative to the sheath tube 3; the distal end of the fastener 4 is provided with an axially extending fixing tube 4-1.

[0070] The barbed structure at the distal end of the fixing component is embedded in the inner wall of the sheath, while the barbed structure at the end tube is embedded in the outer wall of the sheath, thus achieving a fixed connection between the end tube and the sheath. The combination of the double barbed structure makes the connection force between the sheath and the end tube greater, preventing the instrument parts from loosening during the axial movement of the cutter electrode, which would affect the cutting effect and safety.

[0071] Excessive electrode protrusion from the instrument head can lead to unclear markings on the cutting blade during use. In Examples 1-3, the end tube has a through groove extending along its length, with a recess 2-3 at the distal end of the through groove. A blade disc 1-1 is mounted on the blade electrode 1. When the blade electrode 1 is fully retracted towards the proximal end of the sheath 3, the blade disc 1-1 is confined within the recess 2-3, and the blade electrode 1 is at least partially exposed above the end tube 2. The height of the blade electrode 1 protruding above the end tube 2 is 0.20±0.10 mm. This reduces the exposed area of ​​the blade, concentrating the current and achieving hemostasis and electrocoagulation. The blade electrode can also be a column or a hook protruding radially from the outer wall of the electrode rod, etc.

[0072] To limit the length of the blade tip when it extends out of the end tube, the tissue cutting device also includes a connecting tube 5. The connecting tube 5 is provided with a limiting boss 5-1. When the blade tip electrode 1 is fully extended, the limiting boss 5-1 abuts against the proximal end of the fixing member 4 to limit the maximum extension position of the blade tip electrode 1.

[0073] In Examples 1 and 2, the distal portion of the sheath has a variable diameter section, the outer diameter of which is larger than the rest of the sheath 3. A mark 3-1 is provided on the outer surface of the variable diameter section 3-2, positioned close to the end tube 2 along the circumferential direction of the sheath. In Example 1, the mark 3-1 is made of colored ink and adhered to the outer surface of the sheath 3. In Example 2, a mark ring 11 is used, made of stainless steel, with a colored oxide or pigment attached to its surface. In Example 3, the end tube is fitted outside the sheath, and the sheath does not have a variable diameter section; however, the sheath in this example could also have a variable diameter section design.

[0074] With this setup, marker 3-1 and identification ring 11 are used to determine the length of the instrument extending under endoscopic view, preventing excessive extension that could cause perforation.

[0075] The diameter of the sheath tube 3 is changed, and the length and diameter of the variable diameter section 3-2 are controlled to improve the stability of the instrument in the clamp channel. The height of the electrode 1 exposed at the end tube 2 is controlled to improve the marking effect.

[0076] When liquid flows from the distal end of the electrode of the high-frequency electrosurgical unit, it can cause the tissue mucosa to bulge, separating the tissue to be removed from the muscle layer, making it easier to cut. Therefore, a fluid outlet hole is opened on the electrode 1, and / or the distal end of the end tube 2 can also be provided with a fluid outlet hole, and / or the sheath tube 3 can also be provided with a fluid outlet hole.

[0077] The blade electrode 1 can be welded to the connecting tube 5 inside the tissue cutting device, and the connecting tube 5 is further welded to the torque wire inside the tissue cutting device to achieve electrical connection. The flow path of the liquid from the tissue cutting device is as follows: the sheath channel enters the connecting tube channel, then enters the electrode channel, and finally flows out from the distal end of the blade electrode 1.

[0078] To ensure sealing performance, a sealing structure is required to prevent liquid leakage into non-target channels, thus achieving a seal on the outside of the electrode. The sealing structure includes a sealing element 8 and a sealing groove 8-1. The material of the sealing element 8 includes, but is not limited to, elastomers such as silicone and rubber.

[0079] The sealing element 8 is sleeved on the cutter electrode 1 and located in the sealing groove 8-1. The position of the sealing element 8 is constrained by the adjacent components to achieve a seal on the outside of the cutter electrode 1.

[0080] The sealing structure can be set inside the end tube 2, or inside the fixing member 4, or partially inside the end tube 2 and partially inside the fixing member 4.

[0081] In Examples 1 and 2: Since the fixing member is an independent component, the sealing groove 8-1 is located inside the fixing member 4, and the sealing member 8 is located inside the sealing groove 8-1 and sleeved on the cutting electrode 1. The fixing member 4 is sleeved outside the sealing member 8, and the distal ends of both the fixing member 4 and the sealing member 8 abut against the proximal end face of the end tube; the end tube 2 and the fixing member 4 confine the sealing member 8 in the sealing groove 8-1 inside the fixing member 4; the sheath tube 3 is sleeved outside the fixing member 4, and the sheath tube 3 applies a radial force to the fixing member 4 to press the sealing member 8, thereby achieving a seal on the outside of the electrode. Simultaneously, the sealing member 8 applies a reverse pressing force to the cutting electrode 1 and the fixing member 4, thereby further increasing the connection force between the sheath tube and the end tube.

[0082] In embodiment 3, the fixing member 4 is sleeved outside the sealing member 8. The distal ends of both the fixing member 4 and the sealing member 8 abut against the distal end face of the end tube. The sheath tube 3 and the end tube apply a force to the fixing member 4 to press the sealing member 8, thereby achieving a seal on the outside of the electrode. Simultaneously, the sealing member 8 applies a reverse pressing force to the cutter electrode 1 and the fixing member 4. In actual production, a certain gap is provided in the sealing groove of the sealing member.

[0083] When liquid enters the sheath channel, the fluid pressure acts on the seal 8, causing the seal 8 to undergo elastic deformation under compression. The liquid pressure is converted into seal pressure, further enhancing the sealing performance. With this configuration, the seal 8 applies sealing pressure to the tip electrode 1 and the fixing element, while the sheath 3 applies pressure to the tip electrode 1, the fixing element, and the end tube 2. This achieves a seal on the outside of the electrode 1 and seals other channels through which the liquid flows out. The liquid is strictly confined within the electrode channel and flows out through the outlet orifice at the distal end of the tip electrode 1. This concentrated liquid energy more efficiently penetrates the submucosa, forming a mucosal tissue bulge and improving surgical efficiency.

[0084] In the above embodiments, the fixing member is provided independently of the end tube. It should be noted that the end tube and the fixing member can also be integrally formed (e.g., Figures 11-14(As shown). This integrated design eliminates snap-fit ​​components, effectively reducing the number of parts and significantly simplifying the assembly process of the high-frequency electrosurgical unit.

[0085] However, when using a one-piece molding method, both the end tube and the fastener must be made of ceramic or other insulating materials. Due to the processing characteristics of such materials, the barb structure on the fastener can only be designed as an arc shape. Compared to a split structure (independent fastener), the connection strength between the sheath and the end tube in this solution is relatively low.

[0086] Example 4:

[0087] like Figure 11 and Figure 12 As shown, in this embodiment, the end tube and the fixing member adopt an integral molding structure. The fixing member is located at the proximal end of the end tube. The proximal end of the fixing member is provided with a barb structure extending radially outward. The barb structure is embedded in the inner wall of the sheath tube to form a fixed connection between the end tube and the sheath tube, so as to limit the axial displacement of the end tube relative to the sheath tube.

[0088] It also includes a sealing structure, which includes a sealing element 8 and a sealing groove 8-1; the end tube 2 is sleeved outside the sealing structure, and the material of the sealing element 8 includes, but is not limited to, silicone, rubber and other elastomers.

[0089] The sealing groove 8-1 is provided inside the end tube 2. The end tube has a sealing groove extending axially towards the near end of the fixing member, and the opening of the sealing groove is set towards the near end of the fixing member. The sealing member 8 is set inside the sealing groove 8-1 and sleeved on the cutter electrode 1.

[0090] The end tube is sleeved outside the seal 8. The seal can move under force within the sealing groove. When the seal is subjected to axial force, the far end of the seal 8 abuts against the far end of the end tube. Alternatively, the seal can be made immovable, with its far end abutting against the far end of the end tube.

[0091] It also includes a connecting tube 5, which is at least partially housed within the fixing member 4. The sheath tube 3 is sleeved outside the fixing member 4. The end tube 2, the fixing member 4, and the connecting tube 5 confine the seal within the sealing groove 8-1 of the end tube. The sheath tube applies a clamping force to the cutter electrode 1, while the seal 8 applies a reverse clamping force to the electrode 1 and the end tube 2, further enhancing the connection between the sheath tube and the end tube.

[0092] When liquid enters the sheath channel, the fluid pressure acts on the seal 8, causing the seal 8 to undergo elastic deformation under compression. The liquid pressure is converted into seal pressure, further enhancing the sealing performance. With this configuration, the seal 8 applies sealing pressure to the tip electrode 1 and the end tube, while the sheath 3 applies pressure to the tip electrode 1, the fixing element, and the end tube 2, achieving a seal on the outside of the electrode 1. This seals other channels through which the liquid flows out, strictly confining the liquid within the electrode channel and allowing it to flow out only through the fluid outlet at the distal end of the tip electrode 1. This concentrated liquid energy more efficiently penetrates the submucosa, forming a mucosal tissue bulge and improving surgical efficiency.

[0093] To limit the length of the cutter tip extending from the end tube, this embodiment also includes a connecting tube 5. The connecting tube 5 is provided with a limiting boss 5-1, which limits the position of the cutter tip electrode 1 extending from the end tube. When the cutter tip electrode 1 is fully extended, the limiting boss 5-1 is limited to the near end of the fixing member 4. The sealing member 8 is limited by the connecting tube 5 inside the sealing groove of the end tube 2, and the extension of the cutter tip electrode 1 is limited by the end face of the limiting boss 5-1.

[0094] Example 5:

[0095] like Figure 13 and Figure 14 As shown, in this embodiment, the end tube and the fixing member adopt an integral molding structure. The end tube is located at the far end of the outer wall of the sheath tube, and the proximal end of the end tube is at least partially accommodated in the sheath tube. The outer diameter of the proximal end of the end tube is smaller than the inner diameter of the diameter-changing part at the far end of the sheath tube.

[0096] In this embodiment, a sealing groove is provided near the end of the end tube, and the opening of the sealing groove faces the far end of the end tube. The sealing groove 8-1 is located inside the fixing member 4, and the sealing member 8 is located inside the sealing groove 8-1 and sleeved on the cutter electrode. The fixing member 4 is sleeved outside the sealing member 8, and the sealing member can move within the sealing groove. When the sealing member is subjected to axial force, the near end of the sealing member 8 abuts against the inner wall of the near end of the fixing member 4; the sealing member can also be set to be immovable, with its near end abutting against the near end of the fixing member.

[0097] A limiting boss 13 is provided on the cutting electrode 1. The limiting boss 13 restricts the extension position of the cutting electrode 1. When the cutting electrode 1 is fully extended, the limiting boss is flush with the far end of the end tube. When the cutting electrode 1 is retracted, the limiting boss abuts against the far end face of the sealing member 8, thereby limiting the length of the cutting electrode 1 exposed from the end tube 2 and confining the sealing member in the sealing groove.

[0098] like Figure 15 As shown, it also includes an operating unit, which includes a handle 19, an injection handle 15, a connector 21, and a ring 20, with the connector 21 disposed on the ring 20.

[0099] like Figure 15As shown in the enlarged schematic diagram I, a protective tube 14 is provided outside the sheath 3, and the proximal end of the sheath 3 is connected to the distal end of the injection handle 15 by barbs; the barb structure is inserted into the sheath, and the barbs will interlock with the sheath 3 to achieve a fixed connection.

[0100] The cutter electrode 1 is provided with a connecting tube 5 and a torque wire 6 near its end. One end of the connecting tube 5 is connected to the cutter electrode 1, and the other end is electrically connected to the connector 21 by welding to the torque wire 6. A push-pull rod 16 is provided outside the torque wire 6.

[0101] The proximal end of the injection handle 15 is connected to the distal end of the handle 19 by a snap-fit. A sealing ring 18 is provided between the handle 19 and the injection handle 15. A gasket 17 is provided at the rear end of the sealing ring 18 and abuts against the front end of the handle 19 to apply a pressing force to the push-pull rod 16 and the injection handle 15.

[0102] One end of the push-pull rod 16 passes through the gasket 17 and the sealing ring 18, and the other end of the push-pull rod 16 is fixed to the torque wire 6 and the connector 21 at the end face. The fixing method can include, but is not limited to, welding.

[0103] The injection handle 15 and the handle 19 are fixed together by a snap fastener; at the same time, the sealing ring and the gasket are confined inside the injection handle; the sealing ring applies pressure to the push-pull rod and the injection handle respectively to achieve a seal; a gasket is provided at the rear end of the sealing ring to maintain the stability of the sealing ring shape.

[0104] This utility model is applicable not only to monopolar high-frequency electrosurgical units, but also to bipolar electrosurgical units.

[0105] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A tissue cutting device, comprising a cutting electrode and a sheath, wherein the distal end of the sheath is provided with an insulating end tube, and the cutting electrode is axially movable within the end tube, characterized in that, Also includes: A limiting component is provided between the end tube and the sheath tube to limit the axial displacement between them, and has an integral or separate fixing component and a snap-fit ​​component; The fastener is used to secure the end tube and the sheath tube; The snap-fit ​​component is used to fix the fixing component and the end tube or the sheath and the end tube.

2. The tissue incision device of claim 1, wherein, The proximal end of the fastener is provided with a radially outwardly extending barb structure, which is embedded in the inner wall of the sheath to limit the axial displacement of the fastener relative to the sheath; the distal end of the fastener is provided with an axially extending fixing tube.

3. The tissue incision device of claim 2, wherein, The proximal end of the end tube is provided with a fastening part, and the fastening part forms a fixing groove with the distal end of the fixing tube; The at least one snap-fit ​​element is accommodated in the fixing groove and snaps into the fastening portion to connect the end tube to the fixing element.

4. A tissue incision device according to claim 3, wherein The snap-fit ​​component is a C-shaped ring, which is fixed to the far end of the fixing tube and forms a boss; the boss is accommodated in the fixing groove and snaps into the fastening part.

5. A tissue cutting device according to claim 3, characterized in that, The snap-fit ​​component is integrally connected to the fixing tube and located at the far end of the fixing tube, and the snap-fit ​​component includes at least one elastic buckle; The elastic buckle is at least partially accommodated in the fixing groove and engaged with the fastening part.

6. A tissue incision device according to claim 2, wherein The snap-fit ​​component has a radially inwardly extending barb structure disposed on the inner wall of the end tube, the barb structure being embedded in the outer wall of the sheath to restrict axial displacement of the end tube relative to the sheath.

7. A tissue cutting device according to claim 1, characterized in that, It also includes a sealing structure, which comprises a sealing element and a sealing groove; The sealing groove is disposed inside the end tube or inside the fixing member; The seal is housed within the sealing groove to achieve a seal on the exterior of the cutter electrode.

8. A tissue cutting device according to claim 7, characterized in that, The sealing groove is provided inside the fixing member, and the sealing member is provided inside the sealing groove and sleeved on the cutting electrode. The fixing member is sleeved outside the sealing member, the end tube and the fixing member confine the sealing member in the sealing groove inside the fixing member, and the sheath tube applies a force to the fixing member to compress the sealing member.

9. A tissue cutting device according to claim 7, characterized in that, The sealing groove is located inside the end tube, and the sealing element is located inside the sealing groove and sleeved on the cutter electrode; The end tube is sleeved outside the seal, and the seal is confined inside the end tube by the end tube and the fixing member. The sheath tube applies a force to the end tube to compress the seal.

10. A tissue cutting device according to claim 1, characterized in that, The end tube has a through groove extending along the length direction, and a groove is provided at the distal end of the through groove. A cutter disc is provided on the cutter electrode. When the cutter electrode is retracted to its maximum extent toward the proximal end of the sheath tube, the cutter disc is located in the groove, and the cutter electrode is at least partially exposed in the end tube.

11. The tissue incision device of claim 1, wherein, It also includes a connecting tube, which has a limiting boss. When the cutter electrode is fully extended, the limiting boss abuts against the proximal end of the fixing member to limit the maximum extension position of the cutter electrode.

12. The tissue incision device of claim 1, wherein, The distal portion of the sheath has a variable diameter section, the outer diameter of which is larger than the rest of the sheath. The outer surface of the variable diameter section of the sheath is marked and is located close to the end tube along the circumferential direction of the sheath. or / and, An identification ring is provided at the distal end of the variable diameter section of the sheath.

13. A tissue cutting device according to any one of claims 1-12, characterized in that, It also includes an operating unit, which includes a handle, an injection handle, a connector, and a ring, with the connector disposed on the ring; A protective tube is provided outside the sheath, and the proximal end of the sheath is connected to the distal end of the injection handle by a barb. The cutter electrode is provided with a connecting tube and a torque wire near its proximal end. One end of the connecting tube is connected to the cutter electrode, and the other end is electrically connected to the connector by welding to the torque wire. A push-pull rod is provided outside the torque wire. The proximal end of the injection handle and the distal end of the handle are connected by a snap-fit. A sealing ring is provided between the handle and the injection handle, and a gasket is provided at the rear end of the sealing ring and abuts against the front end of the handle to apply a pressing force to the push-pull rod and the injection handle; One end of the push-pull rod passes through the gasket and the sealing ring, and the other end of the push-pull rod is fixed to the torque wire and the connector on the end face.

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