Ferrule

Abstract

The utility model discloses a ferrule, which relates to the technical field of medical instruments and comprises a cutting wire and one or more sleeves, and the sleeves are used for fixing the cutting wire. In the process that the sleeve ring is used for excising the diseased tissue, the cutting wire needs to stretch out of and retract back from the outer sheath tube, and the action of extracting and excising the diseased tissue is achieved. The sleeve tube is used for fixing the cutting wire, the tube sleeve is contained in the outer sheath tube, and the sleeve tube can move in the length direction of the outer sheath tube; in the process, the sleeve can control the state of the cut shreds along with bending of the outer sheath tube, and therefore it is guaranteed that the cut shreds are consistent in the containing process and the releasing process in the process that the cut shreds stretch out or retract back from the outer sheath tube. The utility model aims to provide the ferrule which is high in consistency in the shred containing and releasing process, high in operation precision, high in cutting efficiency, good in effect and simple in structure.

Description

Technical Field

[0001] The utility model belongs to the technical field of medical devices, and particularly relates to a ferrule. Background Art

[0002] Endoscopic mucosal resection (EMR) is a minimally invasive surgery performed under an endoscope, mainly used for treating benign tumors and early malignant tumors in the gastrointestinal tract. This surgery usually requires the use of a high-frequency electrotome device, which cuts and coagulates the diseased tissue through the high-frequency current generated by the electrode, so as to achieve the purpose of removing the lesion.

[0003] The cutting ring is a surgical instrument used in tissue cutting operations. Its essence is to utilize the heat energy generated by the current combined with the mechanical contraction movement to drive the separation of the diseased tissue. Currently, the outer sheath of some bipolar snares is a double lumen tube. When the double lumen tube is in a straight state, the lengths of the two channels of the double lumen tube are the same. However, when it is bent, the lengths of the two channels of the double lumen tube are different. When the instrument enters the human body through the endoscopic forceps channel, usually due to the physiological curvature of the human body, the instrument will be bent passively, which will cause the double lumen of the outer sheath to form a long lumen and a short lumen. The cutting wire connected to the long lumen will have a longer forming stroke, resulting in a shorter cutting wire protruding from the outer sheath on this side; the cutting wire connected to the short lumen will have a shorter forming stroke, resulting in a longer cutting wire protruding from the outer sheath on this side. When tightening the snare to remove the diseased tissue, the shorter cutting wire will enter the outer sheath first, and the longer cutting wire will cause it to be unable to be completely retracted into the outer sheath, resulting in the inability to completely cut off the diseased tissue and causing the instrument to fail. Therefore, it is necessary to design a ferrule in which the cutting wires on both sides extend and retract synchronously in the outer sheath.

[0004] The prior art is an invention patent named bipolar dissector, and the publication number of this invention patent is US11141218B2. This invention discloses a bipolar dissector having a shaft with an insulating insert at its distal end. A working element can be installed in the shaft, and a cutting electrode can move longitudinally in the shaft. The insulating insert has an exposed conductive area of the neutral electrode. The area of the passive neutral electrode exposed transversely to the longitudinal axis forms the conductive top of the insulating insert. The inlet area of the insulating insert has an inner wall. The neutral electrode has two opposite conductive contact surfaces, and the conductive contact surfaces are parallel to the longitudinal axis and contact two parallel conductive contact tubes of the fork, and the cutting ring of the cutting electrode is opened. During the operation, it is difficult for the neutral electrode and the cutting ring of this patent to maintain simultaneous contact with the human tissue. The detachment of either the neutral electrode or the cutting ring from the human tissue will cause the instrument to fail.

[0005] The prior art is an invention patent named "Electrosurgical Instrument for Endoscope or Drain Tube", and the publication number of this invention patent is CN1805716A. This invention patent discloses an electrosurgical instrument for endoscope or drain tube, which can operate not only in contact electrosurgical operations under the action of high-frequency current but also in non-contact plasma coagulation in an ionizable gas. A fixed electrode is provided at the distal end of a catheter in an instrument channel that can introduce an endoscope tube. Its retracted position in the catheter enables an electrosurgical electrode for contact operation to be connected to the electrode through a contact member. The retracted position of the electrode can be but does not necessarily have to be ensured by a stop of a manipulation device or / and by setting and sizing a suitable contact member, without optical monitoring of the retracted position of the electrode. However, this invention uses a monopolar snare in cooperation with a negative electrode plate to excise diseased tissues. The negative electrode plate is attached to the patient's body and cooperates with a high-frequency electrotome device to form a current loop, thereby realizing the cutting and coagulation of diseased tissues. In this process, it is necessary to attach the negative electrode plate to the patient's body, which is not only cumbersome to operate but also may cause overheating and skin burns if the negative electrode plate is not firmly attached or falls off, increasing the risk to the patient. Secondly, the current will flow through the human body, which may pose additional risks to the patient. Summary of the Invention

[0006] The purpose of the present utility model is to provide a snare that can achieve high consistency, high operation accuracy, high cutting efficiency, good effect, and simple structure in the process of wire cutting accommodation and release.

[0007] The technical solution adopted by the present utility model to achieve the above purpose is as follows:

[0008] A snare, comprising a wire and a sleeve. The sleeve is used to fix the wire, and the sleeve is one or more.

[0009] In the process of using the snare to excise diseased tissues, the wire needs to extend out of and retract into the outer sheath tube to perform the actions of snaring and excising the diseased tissues. In this process, the consistency and synchronism of the wire's actions need to be maintained during the extension and retraction of the wire to achieve the complete excision of the diseased tissues. In this application, the sleeve is used to fix the wire. The sleeve is accommodated within the outer sheath tube and can move along the length direction of the outer sheath tube. In this process, the sleeve will control the state of the wire as the outer sheath tube bends, thereby ensuring the consistency of the wire accommodation and release process when the wire extends out of or retracts into the outer sheath tube.

[0010] It should be noted that the wire inside the sleeve is relatively insulated, that is, the wire inside the sleeve will not form a short circuit when powered on. Further, a passage through which the wire can pass can be provided inside the sleeve section.

[0011] Furthermore, the material of the sleeve section is an insulating material.

[0012] It should be noted that the outer sheath tube is made of a flexible material. The outer sheath tube can be inserted into an instrument channel of the endoscope and is at least non-conductive on its outer surface, enabling it to be bent and inserted into the human body. The distal end of the outer sheath tube is open, and the proximal end of the outer sheath tube can be connected to a snare.

[0013] Further, the wire cutting part is made of a conductive material.

[0014] Furthermore, the material of the wire cutting part is a conductive metal material.

[0015] According to an embodiment of the present invention, the sleeve is a tubular structure, and the wire cutting part is sleeved inside the sleeve.

[0016] It should be noted that the sleeve is made of an insulating material.

[0017] According to an embodiment of the present invention, the wire cutting part is a continuous linear structure. The middle section of the wire cutting part can be freely bent, and both ends of the wire cutting part pass through the inside of the sleeve at the same time and are insulated.

[0018] The free bending of the middle section of the wire cutting part realizes a receiving space adapted to the cutting target. It should be noted that the free bending is to correspond to the cutting target. Among them, the shape of the receiving space is adapted to the cutting target, and the shape of the receiving space includes but is not limited to an ellipse, a circle or a polygon.

[0019] According to an embodiment of the present invention, a plurality of sleeves are arranged in sequence along the extending direction of the wire cutting part.

[0020] By arranging the sleeves, the accuracy of attitude control during the movement of the snare outside the outer sheath tube can be improved, thereby improving the stability and smoothness of the movement of the snare and the operation accuracy during the operation.

[0021] According to an embodiment of the present invention, the wire cutting part has a receiving space adapted to the cutting target, and the shape of the receiving space is adapted to the cutting target.

[0022] The receiving space is used to adapt to the cutting target, and the shape of the receiving space includes but is not limited to an ellipse, a circle or a polygon. The cutting target is snared and cut through the receiving space.

[0023] According to an embodiment of the present invention, the wire cutting part is sequentially provided with an inlet section, a cutting section and an outlet section along the direction of the current flow. The receiving space is arranged in the cutting section; the inlet section and the outlet section are wrapped inside the sleeve.

[0024] When a single-pole ferrule is adopted, the cutting wire is provided with an inlet section, a cutting section, and an outlet section arranged in sequence along the current flow direction. The ends of the inlet section and the outlet section are connected to one pole of a current generator, and the other pole of the current generator is arranged on the patient electrode plate. With such an arrangement, the current will be connected through the high-frequency current generator, the cutting wire, the diseased tissue, the patient, the patient electrode plate, and the high-frequency current generator to form a circuit. It should be noted that the inlet section and the outlet section are wrapped inside the sleeve, and through the fixation of the sleeve, during the operation of the single-pole ferrule, the control of the sleeve realizes the stability and accuracy of the movement of the cutting wire along the length of the outer sheath tube.

[0025] Furthermore, the inlet section or the outlet section is wrapped with an insulating material.

[0026] Even further, both the inlet section and the outlet section are wrapped with insulating materials.

[0027] According to an embodiment of the present utility model, the cutting wire includes a first cutting wire monomer and a second cutting wire monomer. The fixed ends of the first cutting wire monomer and the second cutting wire monomer pass through the sleeve and are respectively connected to the positive electrode and the negative electrode of the power supply;

[0028] The free ends of the first cutting wire monomer and the second cutting wire monomer are connected by a structural member. The first cutting wire monomer is wrapped with an insulating tube, and the first cutting wire monomer has an exposed section.

[0029] It should be noted that when the first cutting wire monomer is wrapped with an insulating tube, the sleeve can directly wrap the first cutting wire monomer and the second cutting wire monomer to achieve the mutual insulation of the first cutting wire monomer and the second cutting wire monomer inside the sleeve, that is, there is no need to provide passages in the sleeve section to respectively accommodate the first cutting wire monomer and the second cutting wire monomer, which can reduce the diameter of the sleeve section to adapt to a smaller outer sheath tube and improve the adaptability to different surgical environments.

[0030] When a bipolar ferrule is adopted, the first cutting wire monomer and the second cutting wire monomer are respectively connected to the two poles of the high-frequency current generator. And when the structural member is made of an insulating material, the two electrodes are arranged on the first cutting wire monomer and the second cutting wire monomer. When the ferrule is used on the diseased tissue, a current path can be formed as the first cutting wire, the diseased component, and the second cutting wire to form a loop, thereby realizing the cutting of the diseased tissue. It can not only form a loop for the high-frequency current but also avoid the short circuit of the instrument. It should be noted that the first cutting wire and the second cutting wire are combined together in the sleeve section by bonding or heat shrinking. Even when the outer sheath tube is bent, the first cutting wire and the second cutting wire on both sides can be extended and retracted synchronously in the outer sheath tube, thereby ensuring that the diseased tissue can be completely excised.

[0031] The electrodes of the first cutting wire monomer and the second cutting wire monomer connected to the current generator can be exchanged, that is, the positive electrode and the negative electrode connected by the first cutting wire monomer and the second cutting wire monomer can be mutually converted. This improves the convenience of the ferrule.

[0032] It can be extended that when a monopolar loop is adopted, the structural member can be made of a conductive material. At this time, the first cutting wire monomer and the second cutting wire monomer can conduct current under the action of the structural member. Furthermore, the first cutting wire monomer and the second cutting wire monomer are connected to one pole of a high-frequency current generator, and the other pole of the high-frequency current generator is arranged on the patient plate. Such a setting enables the current to form a closed circuit along the high-frequency current generator, the first cutting wire and the second cutting wire, the diseased tissue, the patient, the patient plate, and the high-frequency current generator. It should be noted that when a monopolar loop is adopted, the structural member can also be made of an insulating material. At this time, it is necessary for the first cutting wire monomer and the second cutting wire monomer to form a path within the structural member.

[0033] Furthermore, the first cutting wire monomer and the second cutting wire monomer are shaped at the end of the structural member to form a receiving space whose shape is adapted to the cutting target. It should be noted that the shape of the receiving space includes, but is not limited to, an oval, a circle, or a polygon.

[0034] Among them, the free ends of the first cutting wire monomer and the second cutting wire monomer are connected by the structural member, and the structural member also has a limiting effect, that is, when the first cutting wire and the second cutting wire are retracted into the outer sheath tube, the structural member prevents the situation where the retraction distance cannot be controlled.

[0035] Furthermore, the distal end of the structural member is provided with an arc-shaped head, which improves the convenience of the movement of the loop during the operation as the loop needs to enter the human body.

[0036] According to an embodiment of the present invention, there is a non-contact spacing distance between the first cutting wire monomer and the second cutting wire monomer within the structural member.

[0037] When a bipolar loop is adopted, there is a non-contact spacing distance between the first cutting wire monomer and the second cutting wire monomer within the structural member, preventing the short-circuit situation between the first cutting wire monomer and the second cutting wire monomer.

[0038] According to an embodiment of the present invention, the lengths of the first cutting wire monomer and the second cutting wire monomer located between the structural member and the closest sleeve are the same and can be freely bent.

[0039] Through the above design, during the process of excising the diseased component, the stability and accuracy of cutting the diseased tissue can be achieved when the first cutting wire monomer and the second cutting wire monomer extend or retract from the outer sheath tube.

[0040] According to an embodiment of the present invention, the first cutting wire has an exposed section on the side of the structural member that is not wrapped with an insulating tube.

[0041] Furthermore, the length of the exposed section is not less than 6 mm. Description of the Drawings

[0042] Figure 1 Schematic diagram of the cooperation between the wire cutter and the sleeve

[0043] Figure 2 Schematic diagram of a ferrule

[0044] Figure 3 Schematic diagram of the current flow direction of a ferrule

[0045] Reference numerals in the drawings: sleeve 1, accommodation space 2, first wire-cutting monomer 3, second wire-cutting monomer 4, structural member 5, insulating tube 6, exposed section 7, outer sheath tube 8 Detailed implementation manners

[0046] The technical solution of the present utility model will be further described in detail below in conjunction with the detailed implementation manners and the drawings:

[0047] Embodiment 1:

[0048] As shown in Figure 1 and Figure 2 , a ferrule includes a wire cutter and a sleeve 1. The sleeve 1 is used to fix the wire cutter, and the sleeve 1 is one or more

[0049] During the process of using the ferrule to excise diseased tissue, the wire cutter needs to extend out of and retract into the outer sheath tube 8 to achieve the actions of snaring and excising the diseased tissue. During this process, the wire cutter needs to maintain the consistency and synchronism of the wire-cutting actions during the extension and retraction processes to achieve the complete excision of the diseased tissue. In this application, the sleeve 1 is used to fix the wire cutter. The sleeve is housed in the outer sheath tube 8, and the sleeve 1 can move along the length direction of the outer sheath tube 8. During this process, the sleeve 1 will control the state of the wire cutter as the outer sheath tube 8 bends, thereby ensuring the consistency of the wire cutter's accommodation and release processes during the extension or retraction of the wire cutter from the outer sheath tube 8

[0050] It should be noted that the wire cutter inside the sleeve 1 is relatively insulated, that is, the wire cutter inside the sleeve 1 will not form a short circuit when powered on. Further, a passage through which the wire cutter can pass can be provided inside the sleeve 1

[0051] Furthermore, the material of the sleeve 1 is a flexible insulating material

[0052] It should be noted that the outer sheath tube 8 is made of a flexible material. The outer sheath tube 8 can be introduced into an instrument channel of an endoscope and is at least non-conductive on its outer surface to enable it to bend and enter the human body. The distal end of the outer sheath tube 8 is open, and the proximal end of the outer sheath tube 8 can be connected to a snare

[0053] Further, the wire cutter is made of a conductive material

[0054] Furthermore, the material of the wire cutter is a conductive metal material

[0055] The sleeve 1 is a tubular structure, and the cutting wire is sleeved inside the sleeve 1.

[0056] It should be noted that the sleeve 1 is made of insulating material.

[0057] The cutting wire is a continuous linear structure. The middle section of the cutting wire can be freely bent, and both ends of the cutting wire pass through the inside of the sleeve 1 at the same time and are insulated.

[0058] The free bending of the middle section of the cutting wire realizes the accommodating space 2 adapted to the cutting target. It should be noted that the free bending is to correspond to the cutting target. Among them, the shape of the accommodating space 2 is adapted to the cutting target, and the shape of the accommodating space 2 includes but is not limited to oval, circular or polygonal.

[0059] A plurality of sleeves 1 are arranged in sequence along the extending direction of the cutting wire.

[0060] By setting the sleeve 1, the accuracy of attitude control of the ferrule during the movement of the outer sheath tube 8 can be improved, thereby improving the stability and smoothness of the movement of the ferrule, and improving the operation accuracy during the operation.

[0061] The cutting wire has an accommodating space 2 adapted to the cutting target, and the shape of the accommodating space 2 is adapted to the cutting target.

[0062] The accommodating space 2 is used to adapt to the cutting target, and the shape of the accommodating space 2 includes but is not limited to oval, circular or polygonal. The cutting target is sleeved and cut through the accommodating space 2.

[0063] The cutting wire is sequentially provided with an inlet section, a cutting section and an outlet section along the current flow direction. The accommodating space 2 is arranged in the cutting section; the inlet section and the outlet section are wrapped inside the sleeve 1.

[0064] When a monopolar ferrule is adopted, the cutting wire is sequentially provided with an inlet section, a cutting section and an outlet section along the current flow direction. Among them, the ends of the inlet section and the outlet section are connected to one pole of a current generator, and the other pole of the current generator is arranged on the patient plate. Such a setting realizes that the current will be connected through the high-frequency current generator, the cutting wire, the diseased tissue, the patient, the patient plate, and the high-frequency current generator. It should be noted that the inlet section and the outlet section are wrapped inside the sleeve 1, and through the fixation of the sleeve 1, during the operation of the monopolar ferrule, the control of the sleeve 1 realizes the stability and accuracy of the cutting wire moving along the length of the outer sheath tube 8.

[0065] Furthermore, the inlet section or the outlet section is wrapped with insulating material.

[0066] Even further, both the inlet section and the outlet section are wrapped with insulating material.

[0067] The wire cutting includes a first wire cutting monomer 3 and a second wire cutting monomer 4. The fixed ends of the first wire cutting monomer 3 and the second wire cutting monomer 4 pass through the sleeve 1 and are respectively connected to the positive and negative poles of the power supply;

[0068] The free ends of the first wire cutting monomer 3 and the second wire cutting monomer 4 are connected by a structural member 5. The first wire cutting monomer 3 is wrapped with an insulating tube 6, and the first wire cutting monomer 3 has an exposed section 7.

[0069] It should be noted that when the first wire cutting monomer is wrapped with the insulating tube 6, the sleeve 1 can directly wrap the first wire cutting monomer 3 and the second wire cutting monomer 4 to achieve mutual insulation between the first wire cutting monomer 3 and the second wire cutting monomer 4 inside the sleeve 1. That is, there is no need to provide passages in the sleeve 1 section to respectively accommodate the first wire cutting monomer 3 and the second wire cutting monomer 4, and the diameter of the sleeve 1 section can be reduced to adapt to an outer sheath tube 8 with a smaller diameter, so as to improve the adaptability to different surgical environments.

[0070] When a bipolar loop is used, the first wire cutting monomer 3 and the second wire cutting monomer 4 are respectively connected to the two poles of a high-frequency current generator, and when the structural member 5 is made of an insulating material, the two electrodes are arranged on the first wire cutting monomer 3 and the second wire cutting monomer 4. When the loop is used to treat diseased tissues, the current path can be formed as the first wire cutting, the diseased component, and the second wire cutting to form a loop, thereby realizing the cutting of the diseased tissues. It can not only form a loop for high-frequency current but also avoid short-circuiting of the instrument. It should be noted that the first wire cutting and the second wire cutting are combined together in the sleeve 1 section by bonding or heat shrinkage. Even when the outer sheath tube 8 is bent, the first wire cutting and the second wire cutting on both sides can be extended and retracted synchronously in the outer sheath tube 8, thereby ensuring that the diseased tissues can be completely removed.

[0071] The electrodes of the first wire cutting monomer 3 and the second wire cutting monomer 4 connected to the current generator can be exchanged, that is, the positive and negative poles connected by the first wire cutting monomer 3 and the second wire cutting monomer 4 can be mutually converted. This improves the convenience of the loop.

[0072] It can be extended that when a monopolar loop is used, the structural member 5 can be made of a conductive material. At this time, the first wire cutting monomer 3 and the second wire cutting monomer 4 can conduct current under the action of the structural member 5. Then, the first wire cutting monomer 3 and the second wire cutting monomer 4 are connected to one pole of a high-frequency current generator, and the other pole of the high-frequency current generator is arranged on the patient's electrode plate. Such a setting realizes that the current will be connected through the high-frequency current generator, the first wire cutting and the second wire cutting, the diseased tissue, the patient, the patient's electrode plate, and the high-frequency current generator. It should be noted that when a monopolar loop is used, the structural member 5 can also be made of an insulating material. At this time, it is necessary for the first wire cutting monomer 3 and the second wire cutting monomer 4 to form a path inside the structural member 5.

[0073] Furthermore, the first wire cutting monomer 3 and the second wire cutting monomer 4 form a receiving space 2 with a shape adapted to the cutting target at the end of the structural member 5 through shaping. It should be noted that the shape of the receiving space 2 includes, but is not limited to, an oval, a circle or a polygon.

[0074] Among them, the free ends of the first wire cutting monomer 3 and the second wire cutting monomer 4 are connected by the structural member 5, and the structural member 5 also has a limiting effect, that is, when the first wire and the second wire are retracted into the outer sheath tube 8, the structural member 5 prevents the situation where the retraction distance cannot be controlled.

[0075] Furthermore, the distal end of the structural member 5 is provided with an arc-shaped head, which improves the convenience of the movement of the ferrule during the operation because the ferrule needs to enter the human body.

[0076] There is a non-contact spacing distance between the parts of the first wire cutting monomer 3 and the second wire cutting monomer 4 inside the structural member 5.

[0077] When a bipolar ferrule is adopted, there is a non-contact spacing distance between the parts of the first wire cutting monomer 3 and the second wire cutting monomer 4 inside the structural member 5 to prevent the short circuit of the first wire cutting monomer 3 and the second wire cutting monomer 4.

[0078] The lengths of the first wire cutting monomer 3 and the second wire cutting monomer 4 located between the structural member 5 and the closest sleeve 1 are the same and can be freely bent.

[0079] Through the above design, during the process of excising the diseased component, when the first wire cutting monomer 3 and the second wire cutting monomer 4 extend or retract from the outer sheath tube 8, the stability and accuracy of cutting the diseased tissue can be achieved.

[0080] The first wire has an exposed section 7 on the side of the structural member 5 that is not wrapped with the insulating tube 6.

[0081] Further, the length of the exposed section 7 is not less than 6 mm.

[0082] The above-described embodiments have detailed the technical solutions of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modification, supplement or substitution in a similar way within the principle scope of the present invention should be included within the protection scope of the present invention.

Claims

1. A ferrule, comprising a cut wire and a sleeve (1), wherein the sleeve (1) is used to fix the cut wire, characterized in that: The sleeve (1) is one or more; The shredder has a receiving space (2) adapted to the cutting target, and the shape of the receiving space (2) is adapted to the cutting target; The wire cutter is provided with an inlet section, a cutting section and an outlet section in sequence along the current flow direction, and the accommodating space (2) is provided in the cutting section; the inlet section and the outlet section are wrapped inside the sleeve (1).

2. A ferrule according to claim 1, characterized in that: The sleeve (1) is a tubular structure, and the shredder sleeve is arranged inside the sleeve (1).

3. A ferrule according to claim 1, characterized in that: The plurality of sleeves (1) are arranged in sequence along the extension direction of the cut wire.

4. A ferrule according to claim 1, characterized in that: The cut wire is a continuous linear structure, the middle section of the cut wire can be bent freely, and the two ends of the cut wire simultaneously pass through the interior of the sleeve (1) and are insulated.

5. The ferrule according to claim 1, characterized in that: The shredder comprises a first shredder unit (3) and a second shredder unit (4), wherein the fixed ends of the first shredder unit (3) and the second shredder unit (4) pass through the sleeve (1) and are respectively connected to the positive electrode and the negative electrode of the power source; The free ends of the first cutting wire unit (3) and the second cutting wire unit (4) are connected via a structural member (5), the first cutting wire unit (3) is wrapped with an insulating tube (6), and the first cutting wire has an exposed section (7).

6. A ferrule according to claim 5, characterized in that: The first shredded monomer (3) and the second shredded monomer (4) in the structural member (5) have a non-contact spacing distance.

7. A ferrule according to claim 5, characterized in that: The first shredded unit (3) and the second shredded unit (4) located between the structural member (5) and the closest sleeve (1) have the same length and are freely bendable.

8. A ferrule according to claim 5, characterized in that: The first cut wire unit (3) has an exposed section (7) on the structural member (5) side that is not wrapped with the insulating tube (6).

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