Rotatable electric snare

Abstract

The invention relates to a rotatable electric snare, and belongs to the technical field of medical instruments. The snare comprises a snare, an outer sheath tube, an inhaul cable, a conductive electrode, a core rod and a sliding ring, the snare is fixedly connected with the front end of the inhaul cable, and the outer sheath tube is connected with the core rod; the conductive electrode comprises an electrode plug, an electrode base and a fastening screw, the electrode base is fixed on the slip ring, a longitudinal threaded hole and a transverse through hole are formed in the electrode base, and the longitudinal threaded hole is communicated with the transverse through hole; the boosting rod is located in the core rod and extends in the length direction of the core rod, the tail end of the inhaul cable is fixedly connected with the front end of the boosting rod, the tail end of the boosting rod is inserted into a transverse through hole of the electrode base, and a fastening screw used for fastening the boosting rod is arranged in a longitudinal threaded hole of the electrode base. And the electrode plug is inserted into the longitudinal threaded hole and is in threaded connection with the electrode base. According to the invention, the electrode plug and the slip ring can be firmly fixed, and the current conduction effect is ensured.

Description

Technical Field

[0001] The invention relates to a rotatable electric snare, belonging to the technical field of medical devices. Background Art

[0002] The electric snare can be used in conjunction with high-frequency surgical equipment to use high-frequency current to remove polyps or other excess tissues in the digestive tract. The electric snare usually includes a snare at the front end of the operation, a push handle and a handle at the rear end of the operation. The push handle is provided with an electric plug for connecting the power supply. The snare is connected to the push handle through a pull cable. The push handle is slidably connected on the handle. By pushing the push handle forward, the snare can be controlled to extend out of the outer sheath, and when the push handle is pulled back, the snare is synchronously retracted into the outer sheath. During endoscopic surgery, if the snare at the front end of the operation is not in the same operating plane as the lesion tissue to be removed, the electric snare needs to be rotated as a whole, that is, the direction of the snare is adjusted according to the location of the lesion to ensure that the snare can accurately trap the tissue to be removed. However, since the entire snare needs to be operated through the endoscope channel, it is very inconvenient to rotate the whole snare.

[0003] The applicant searched and found that the Chinese patent document with publication number CN217430160U (application number 202221173065.2) discloses a snare conductive connection structure of an electric snare, in which the electrode seat is fixedly connected to the rear end of the electrode connector, a through hole is provided in the electrode seat, a rigid conductive column passes through the through hole and contacts the inner wall of the through hole, the rigid conductive column can rotate relative to the electrode seat and remain relatively fixed with the electrode seat in the axial direction, and there is a limit surface on the outer wall of the rigid conductive column to prevent rotation. The rigid conductive column passes through the central hole of the snare knob, and when the knob is turned, the rigid conductive column and the knob rotate synchronously through the limit surface. In this patent, the rigid conductive column passes through the through hole of the electrode seat and contacts the inner wall of the through hole, and the rigid conductive column can rotate relative to the electrode seat, but the tolerance matching of the rigid conductive column and the through hole of the electrode seat is difficult to control. The rigid conductive column can rotate in the through hole of the electrode seat, and it cannot be guaranteed that the rigid conductive column can reliably contact with the inner wall of the through hole (the inner wall of the through hole of the electrode seat and the rigid conductive column can effectively conduct electricity only when they are effectively in contact), and there is a risk of poor conductivity.

[0004] The applicant further searched and found that the Chinese patent document with publication number CN216148183U (application number 202121619731.6) discloses a rotatable snare, with a positioning bolt on the push handle, a center hole and a power plug on the positioning bolt, and a pressure groove at the rear end of the cable. When the cable passes through the center hole, it forms a one-time match with the end of the power plug. The cable is fixed on the push handle, and the rear end of the handle can be rotated to adjust the angle of the snare by rotating the cable. In this patent, when the end of the electrode plug is against the cable pressure groove, the upper end of the electrode plug is also firmly fixed to the handle, but in actual production, due to part tolerances and assembly errors, it is difficult to ensure that when the electrode plug is against the cable pressure groove, the upper end of the electrode plug is also firmly fixed to the handle. There may be a gap between the upper end of the electrode plug and the handle, and the fixation is not firm. The cable is generally woven with 304 stainless steel wire and has poor rigidity. When the handle drives the cable out, the cable may bend in the long limit hole of the handle, affecting the snare from the outer sheath and affecting the efficiency of the operation. Summary of the invention

[0005] The technical problem to be solved by the present invention is: how to ensure that the snare is smoothly extended and recovered from the outer sheath tube, and how to firmly fix the electrode plug and the slip ring under the premise of ensuring the current conduction effect.

[0006] In order to solve the above technical problems, the present invention provides a rotatable electric snare, comprising a snare, an outer sheath, a cable, a conductive electrode, a core rod and a slip ring, wherein the snare and the front end of the cable are fixedly connected, the outer sheath is connected to the front end of the core rod, and the slip ring can slide along the length direction of the core rod to form a moving pair with the core rod; the conductive electrode comprises an electrode plug, an electrode base and a set screw, the electrode base is fixed on the slip ring, a longitudinal threaded hole and a transverse through hole are provided on the electrode base, and the longitudinal threaded hole and the transverse through hole penetrate each other; the booster rod is located in the core rod and extends along the length direction of the core rod, the tail end of the cable is fixedly connected to the front end of the booster rod, the tail end of the booster rod is inserted into the transverse through hole, and a set screw for fastening the booster rod is provided in the longitudinal threaded hole of the electrode base; the electrode plug is inserted into the longitudinal threaded hole and is screwed with the electrode base, the conductive electrode and the snare are electrically connected through the electrode base, the booster rod and the cable, and a preset gap is provided between the electrode plug and the set screw.

[0007] The present invention arranges a rigid booster rod between the tail end of the cable and the conductive electrode so that the booster rod supports the cable, thereby overcoming the defect in the prior art that the cable bends inside the core rod due to poor rigidity of the cable, affecting the snare from being pushed out of the outer sheath tube, thereby ensuring that the snare is smoothly extended and recovered from the outer sheath tube, improving the efficiency of the operation, and the connection method is reliable and low in cost.

[0008] The present invention inserts the booster rod into the transverse through hole of the electrode base and presses the booster rod by a set screw, so that the booster rod is firmly connected to the electrode base, and the electrode plug is screwed to the electrode base. Therefore, the electrode plug and the core rod are firmly fixed, stable and reliable, and easy to install. Moreover, the electrode plug is electrically connected to the snare through the electrode base, the booster rod and the cable, which effectively avoids the defect of poor conductivity risk in the prior art and ensures the current conduction effect.

[0009] In the present invention, the electrode base and the electrode plug are fixed to the slip ring by threads, and a set screw is used instead of a push rod to fix the electrode plug, so that a tight fit between the electrode plug and the slip ring can be ensured, thereby eliminating the risk of loose fixation caused by a gap between the upper end of the electrode plug and the slip ring when the lower end of the electrode plug abuts against the push rod in the prior art.

[0010] It should be noted that, in the present invention, the front end refers to the end close to the snare, and the tail end refers to the end close to the conductive electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The present invention will be further described below in conjunction with the accompanying drawings.

[0012] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0013] Figure 2 It is a schematic diagram of the installation of conductive electrodes.

[0014] Figure 3 It is a schematic diagram of the structure of the electrode base.

[0015] Figure 4 yes Figure 3 Schematic cross-section diagram of .

[0016] Figure numerals: 1, snare; 2, outer sheath; 3, pull cable; 4, booster rod; 5, conductive electrode; 6, core rod; 7, slip ring; 51, electrode plug; 52, electrode base; 53, set screw; 521, longitudinal threaded hole; 522, transverse through hole; 71, electrode fixing hole. DETAILED DESCRIPTION

[0017] This embodiment relates to a rotatable electric snare, such as Figure 1-Figure 3 As shown, it includes a snare 1, an outer sheath tube 2, a cable 3, a conductive electrode 5, a core rod 6 and a slip ring 7. The front ends of the snare 1 and the cable 3 are fixedly connected, the outer sheath tube 2 is connected to the front end of the core rod 6 (the front end of the core rod 6 is provided with a rotating cap, and the outer sheath tube 2 is installed on the rotating cap), the conductive electrode 5 is fixed on the slip ring 7, and the slip ring 7 can slide along the length direction of the core rod 6 to form a moving pair with the core rod 6. The above is the prior art, and the two patent documents cited in the background technology part can be referred to, which will not be repeated here.

[0018] In this embodiment, the conductive electrode 5 is as follows Figure 2-Figure 4 As shown, it includes an electrode plug 51, an electrode base 52 and a set screw 53. The electrode base 52 is fixed on the slip ring 7. The electrode base 52 is provided with a longitudinal threaded hole 521 and a transverse through hole 522. The longitudinal threaded hole 521 and the transverse through hole 522 penetrate each other. The booster rod 4 is located in the core rod 6 and extends along the length direction of the core rod 6. The tail end of the cable 3 is fixedly connected to the front end of the booster rod 4, and the tail end of the booster rod 4 is inserted into the transverse through hole 522. Preferably, the front end of the cable 3 is connected to the snare 1 by riveting, and the tail end of the cable 3 is fixed to the booster rod 4 by riveting.

[0019] A set screw 53 for fastening the booster rod 4 is provided in the longitudinal threaded hole 521 of the electrode base 52, so as to achieve the effect of fixing and conducting the conductive electrode 5 and the booster rod 4, that is, the electrode plug 51 is inserted into the longitudinal threaded hole 521 and screwed to the electrode base 52, and the conductive electrode 5 and the snare 1 are electrically connected through the electrode base 52, the booster rod 4 and the cable 3.

[0020] The set screw 53 is preferably a concave end set screw 53 , such as a hexagon socket set screw 53 , so that the axial length of the longitudinal threaded hole 521 can be fully utilized and the size of the longitudinal threaded hole 521 can be reduced.

[0021] There is a preset gap between the electrode plug 51 and the set screw 53, and the gap is used to prevent the lower end of the electrode plug 51 from hitting the upper end of the set screw 53, so the length of the electrode plug 51 should be controlled.

[0022] Preferably, in order to improve the fastening effect, a pit is provided at the riveting position between the tail end of the cable 3 and the booster rod 4 (for example, it can be formed during riveting), and the set screw 53 abuts against the pit.

[0023] In this embodiment, the booster rod 4 supports the cable 3, which is not only reliable and low-cost, but also prevents the cable 3 from bending in the core rod 6 and affecting the release of the snare 1. The length of the booster rod 4 can be set as needed, generally speaking, as long as it does not affect the release and retraction of the snare 1.

[0024] In addition, in this embodiment, the set screw 53 replaces the electrode plug fixing push rod in the prior art, which can ensure a tight fit between the electrode plug 51 and the slip ring 7, eliminating the risk of loose fixation caused by a gap between the upper end of the electrode plug and the slip ring when the lower end of the electrode plug in the prior art abuts against the push rod.

[0025] When this embodiment is implemented, Figure 1 and Figure 2 As shown, an electrode fixing hole 71 may be provided on the slip ring 7, the electrode plug 51 and the electrode base 52 are respectively located at the upper end and the lower end of the electrode fixing hole 71, and the electrode base 52 is fixed to the slip ring 7 by threaded connection, that is, the electrode base 52 is inserted into the electrode fixing hole 71 and is threadedly connected to the slip ring 7. The electrode fixing hole 71 serves to protect the electrode plug 51 and the electrode base 52.

[0026] The assembly method of this embodiment is as follows: first, the tail end of the cable 3 with the snare 1 is fixed to the booster rod 4 by riveting, and there should be a pit at the riveting position; then, the tail end of the booster rod 4 is inserted into the transverse through hole 522 of the electrode base 52, and the concave end fixing screw 53 is tightened in the longitudinal threaded hole 521 so that the lower end of the concave end fixing screw 53 is stuck in the riveting pit of the booster rod 4, and then the electrode plug 51 is installed on the electrode base 52, and then the electrode base 52 and the slip ring 7 are fixed by threads, and finally the slip ring 7 is sleeved on the outer wall of the core rod 6.

[0027] When in use, the slip ring 7 cooperates with the core rod 6, and the slip ring 7 slides along the core rod 6, driving the cable 3 to extend and retract the snare 1. When the handle formed by the slip ring 7 and the core rod 6 rotates, the rotation of the slip ring 7 and the core rod 6 causes the conductive electrode 5 to drive the booster rod 4 and the cable 3 to rotate, thereby realizing the rotation of the snare 1 at an angle.

[0028] This embodiment can firmly fix the electrode plug 51 and the handle, and firmly connect the electrode plug 51 and the booster rod 4. When the handle is rotated, the booster rod 4 and the cable 3 can be driven to rotate, while ensuring the current conduction effect.

Claims

1. A rotatable electric snare, comprising a snare, an outer sheath, a cable, a conductive electrode, a core rod and a slip ring, wherein the snare is fixedly connected to the front end of the cable, the outer sheath is connected to the front end of the core rod, and the slip ring can slide along the length direction of the core rod to form a moving pair with the core rod; characterized in that: The conductive electrode comprises an electrode plug, an electrode base and a set screw, wherein the electrode base is fixed on the slip ring, and a longitudinal threaded hole and a transverse through hole are provided on the electrode base, wherein the longitudinal threaded hole and the transverse through hole penetrate each other; The booster rod is located inside the core rod and extends along the length direction of the core rod, the tail end of the cable is fixedly connected to the front end of the booster rod, the tail end of the booster rod is inserted into the transverse through hole, and a set screw for fastening the booster rod is provided in the longitudinal threaded hole of the electrode base; The electrode plug is inserted into the longitudinal threaded hole and screwed to the electrode base. The conductive electrode and the snare are electrically connected through the electrode base, the booster rod and the cable. There is a preset gap between the electrode plug and the set screw.

2. The rotatable electric snare according to claim 1, characterized in that: The slip ring is provided with an electrode fixing hole, and the electrode base is inserted into the electrode fixing hole and is screwed to the slip ring.

3. The rotatable electric snare according to claim 1, characterized in that: The set screw is a concave end set screw.

4. The rotatable electric snare according to claim 1 or 2, characterized in that: The front end of the cable is connected to the loop by riveting, and the rear end of the cable is fixed to the booster rod by riveting.

5. The rotatable electric snare according to claim 4, characterized in that: A pit is provided at the riveting position between the tail end of the cable and the booster rod, and the set screw abuts against the pit.

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