Reinforced working channel tube

Abstract

A method of producing a wire coil reinforced working channel tube for an endoscope, comprising: providing a working channel tube reinforced with a wire coil, the wire coil being embedded between an inner surface and an outer surface of the working channel tube, a non-embedded wire portion extending out of the outer surface of the tube from an exit point; extending the non-embedded wire portion from the exit point to a rotational position located in the non-embedded space; bending the non-embedded wire portion in the rotational position to form a bend and a first non-embedded wire sub-portion extending from the exit point to the bend and a second non-embedded wire sub-portion extending after the bend; extending the second non-embedded wire sub-portion back across the tube to a clamped position in the embedded space; clamping the second non-embedded wire sub-portion at a clamping position in the clamp; the non-embedded wire sub-portions are rotated at a rotational position to twist the first non-embedded wire sub-portion and the second non-embedded wire sub-portion about each other until the wire breaks. A working channel tube, an endoscope, and a visualization system are also disclosed.

Description

Technical Field

[0001] The present disclosure relates to a method for providing a reinforced working channel tube for an endoscope, a working channel tube made by the method, an endoscope including the reinforced working channel tube, and a visualization system including the endoscope. Background Art

[0002] Endoscopes are known and are used for visual navigation into hollow organs and body cavities and for inspection and diagnosis, and optionally for assisting surgical procedures, such as for sampling target tissue. Endoscopes include surgical endoscopes, such as gastroscopes and colonoscopes. The endoscope may include a handle grasped by an operator at the proximal end, and a flexible, elongated insertion line extending distally from the handle. Alternatively, the endoscope may include an interface at the proximal end for cooperating with a drive device, such as for implementing robotic endoscopic examinations. The insertion line may include an insertion tube that terminates at a distal end portion at the end of a highly flexible (e.g., hinged) curved section that can be controlled by an operator. The end portion may include an observation optical system extending distally from the curved section.

[0003] The controllable bending section can be an articulated section at the distal end of the elongated insertion line. The bending section can be controlled by an operator via a control wheel arranged on the handle. The control wheel can be connected to the bending section by a control cable. Pulling the control cable can make the bending section bend in one direction. A plurality of control cables can be provided to bend the bending section in a given direction to guide the distal end in a specific direction, such as in two opposite directions or in four directions (for example, two opposite directions in a first plane and two opposite directions in a second plane at right angles to the first plane).

[0004] Thus, using the control wheel allows the operator to advance the distal tip of the endoscope to a desired position by means of a series of actions including, among others, bending the bending section in a desired direction, advancing the elongated insertion wire, and twisting the elongated insertion wire.

[0005] An endoscope typically includes an internal working channel extending from a working channel access port of an endoscope handle to a distal tip unit of an insertion line, thereby providing a multifunctional channel from the handle to the distal tip. The working channel can be used to guide surgical tools through the internal working channel into a patient's body cavity, i.e., distally relative to the tip of the endoscope. In addition, the internal working channel can typically also be used as a suction channel to extract, for example, body fluids from an operating area within a patient's body cavity and / or as a flushing channel to supply fluid to an operating area or a following area, from which a sample is collected by aspirating and collecting the supplied fluid, as is done, for example, in a bronchoalveolar lavage procedure.

[0006] The inner working channel is usually formed by a connector part, a so-called biopsy connector or Y-connector, a flexible working channel tube arranged inside the endoscope handle, an insertion tube and a bending section, and a tip housing of the distal tip unit.

[0007] In addition to the internal working channel, there are also known external working channels, which can be mounted externally to the insertion line of the endoscope and can be used as additional cavities for guiding instruments into the patient's body cavity, for withdrawing body fluids from the operating area, etc.

[0008] Both the inner and outer working channels typically include a flexible working channel tube having an elongated hollow tubular body typically made of a polymer material.

[0009] When the actively bendable bending section of the insertion line (for example, a wheel or lever provided at the endoscope handle by manual operation) is bent, there is a risk of kinking of the working channel tube due to insufficient stability. Kinking is usually accompanied by a change in the cross-sectional shape of the working channel tube. In particular, the cross-sectional shape of the working channel tube is no longer circular in some sections. This may affect the movement of the instrument inside the working channel tube and the suction performance, especially in the case where the kink causes the working channel tube to shrink.

[0010] It is therefore desirable to reduce or avoid the risk of kinking of the working channel tube during operation of the endoscope, particularly during bending of the actively bendable bending section. In view of this, it has been previously suggested to provide a reinforced working channel tube.

[0011] For example, US 6 315 715 B1 discloses a flexible endoscope with a working channel. The working channel is a flexible tube with a convoluted section in which the wall of the tube is folded to increase flexibility. External helical reinforcement coils can be added externally between the external convolutes.

[0012] Further, US 4 714 075 A discloses a working channel for a flexible endoscope, wherein the working channel is reinforced with a metal knitted or woven fabric.

[0013] In addition, US Pat. No. 4,676,229 A discloses an endoscope having a working channel, the working channel comprising a plastic tube and a metal wire helically wound around the plastic tube. The metal wire is bonded to the outer surface of the plastic tube using an adhesive.

[0014] Therefore, it is known from the prior art to provide a reinforced working channel tube. However, existing reinforced working channel tubes have, inter alia, the problem that their production methods involve high costs and complexity. In addition, existing reinforcement methods may not be suitable for reinforcing very small working channel tubes with very small wall thicknesses without increasing the outer diameter of the working channel tube, which goes against the general desire in the field of endoscopy to provide an endoscope in which the outer diameter of the insertable part is as small as possible in order to reduce the invasiveness of the surgical procedure using the endoscope. In addition to this, some of the reinforcement materials used (e.g. knitted or woven fabrics) may unacceptably reduce the flexibility of the curved section, in particular when used in very small working channel tubes with very small wall thicknesses. Summary of the invention

[0015] The object of the present disclosure is to provide a solution that at least improves upon the solutions of the prior art. In particular, the object of the present disclosure is to provide a method for producing a reinforced working channel tube, wherein the variation in the inner and outer dimensions of the working channel tube is minimal. Further provided is a method capable of reinforcing a longitudinal cross-section of a working channel tube to customize the properties of the tube. Accordingly, in a first aspect, a method for producing a wire coil reinforced working channel tube for an endoscope is disclosed. The method comprises:

[0016] a) providing a working channel tube reinforced with a wire coil embedded between an inner surface and an outer surface of the working channel tube, wherein a non-embedded wire portion of the wire coil extends out of the outer surface of the tube from an exit point, wherein an exit point tangent line tangent to the outer surface at the exit point defines two opposite directions extending away from the exit point:

[0017] i. a non-embedded direction extending away from the final embedded wire portion leading to the exit point; and

[0018] ii. an embedding direction opposite to the non-embedding direction;

[0019] wherein an outlet plane extends through the outlet point and the longitudinal axis of the tube, and spaces extending from the outlet plane along the non-embedded direction and the embedded direction are defined as non-embedded space and embedded space, respectively;

[0020] b) fixing the working channel tube;

[0021] c) extending the non-embedded wire portion from the exit point to a rotational position within the non-embedded space;

[0022] d) bending the non-embedded wire portion at the rotational position, thereby forming a bend and a first non-embedded wire sub-portion extending from the exit point to the bend and a second non-embedded wire sub-portion extending after the bend;

[0023] e) extending the second non-embedded wire sub-portion back across the tube to a clamping position within the embedment space;

[0024] f) clamping the second non-embedded wire sub-portion at the clamping location in a clamp; and

[0025] g) rotating the non-embedded wire sub-portion at the rotational position such that the first non-embedded wire sub-portion and the second non-embedded wire sub-portion twist around each other until the wire breaks.

[0026] The advantage of this method is that it provides a reinforced working channel tube with minimal wire protrusion in a simple, efficient, repeatable and low-cost manner. This further facilitates the breaking of the wires of the wire coil below the outer surface of the tube, which means that no wire protrudes from the outer surface of the tube. This can also eliminate the need for potential post-processing to reduce the impact of any wire protrusion (e.g., by cutting, grinding or covering the existing protrusion with an adhesive or another material, which is usually a labor-intensive process). As suggested in the background section, providing such a tube for an assembled endoscope can improve its mobility while having the kink resistance of a reinforced working channel tube.

[0027] As known to those skilled in the art, a wire coil reinforced working channel tube can be provided in a variety of appreciable ways. One example can include: providing a working channel tube made of a plastic material; softening the outer surface of the tube by heat; and winding a wire into the outer surface of the tube to form a wire coil embedded in the tube. The wire can be spirally wound into the outer surface. Softening the outer surface of the tube can involve melting the surface. In a variation of this embodiment, chemicals can be used to soften and / or melt the outer surface. Solidification of the plastic material of the tube can be used to anchor the wire coil in the tube.

[0028] The secured working channel tube helps ensure that the tube does not move when the first and second non-embedded wire subsections are rotated at the rotational position, which creates a pulling force on the tube through the first non-embedded wire subsection, thereby allowing tension to build up in the wires.

[0029] In a variation of the present embodiment, the working channel tube is fixed so as to prevent translational movement and rotational movement. For example, the working channel tube can be fixed by clamping the working channel tube in place and / or by pressing into a press-fit retainer. The press-fit retainer can be, for example, U-shaped, V-shaped, groove-shaped, etc. The working channel tube can be fixed at more than one fixed position, such as 2, 3, 4, 5, 6, 7 or more fixed positions. The working channel tube can be fixed at least at a position near the corresponding exit point and at a position far from the corresponding exit point. The near side can be understood as the direction of the handle toward the assembled endoscope, and the far side can be understood as the direction toward the distal end of the assembled endoscope. The working channel tube can be fixed so that there are fixed positions within 10 working channel tube outer diameters or less located at the near side of the corresponding exit point and fixed positions within 10 working channel tube outer diameters or less located at the far side of the corresponding exit point. This can facilitate the method by ensuring that the tube is optimally supported and fixed to prevent movement and bending of the tube during the rotation of the wire (which may have a negative impact on the results of the method).

[0030] The rotational position in the non-embedded space helps prevent pulling of the embedded wire from the first non-embedded wire sub-portion caused by rotation and twisting of the wire sub-portions in a direction that pulls out the embedded wire.

[0031] Rotation at the rotational position can be substantially around the longitudinal axis of the first non-embedded wire sub-portion extending between the exit point and the rotational position. Rotating the non-embedded wire sub-portions so that they twist around each other creates tension in the wire and further can be used in a simple and controllable manner to fatigue the wire, thereby causing the wire to break. The wire may break due to a torsional fracture, which may be below the outer surface of the tube or flush with the outer surface of the tube.

[0032] In another variation of this embodiment, the rotational position may include a fixture that clamps the first sub-wire portion and the second sub-wire portion in place. If such a fixture is provided, then in step g), the fixture may be rotated to rotate the wire at the rotational position until the wire breaks. As an alternative to such a fixture, the rotational position may include a geometric shape (such as a hook or loop), and in step d), the non-embedded wire portion may be bent around the geometric shape so that the bend is formed around the geometric shape, wherein, in step g), the geometric shape may be rotated to rotate the non-embedded wire sub-portion at the rotational position until the wire breaks. Rotation may be provided using a rotator (such as an electric motor).

[0033] Bend the non-embedded wire portion at the rotational position and extend the second non-embedded wire sub-portion back across the tube to a clamping position located in the embedded space to help ensure that the first non-embedded wire sub-portion and the second non-embedded wire sub-portion will twist around each other and form a winding portion from the rotational position to the exit point when the non-embedded wire portion is rotated at the rotational position. The winding portion of the non-embedded wire sub-portion formed from the rotational position to the exit point helps to ensure the complete breakage of the wire below the outer surface of the tube. Extending the second non-embedded wire sub-portion back across the tube can be understood as extending the second non-embedded sub-portion back to the portion where the exit point of the tube is located. The second non-embedded wire sub-portion can extend back across the tube through a space perpendicular to the exit point. The second non-embedded wire sub-portion can extend back across the tube so that at least a section of the second non-embedded wire sub-portion extends perpendicular to the exit point and the outer surface of the tube above the exit point. The second non-embedded wire sub-portion can extend back across the tube substantially in a straight line. In a variation of this embodiment, the second non-embedded wire subportion extends back across the tube substantially parallel to the first non-embedded wire subportion.

[0034] In a variation of this embodiment, the clamp in which the second non-embedded wire sub-portion is clamped is configured to allow the wire to slip, so that the length of the wire slides out of the clamp when it is pulled to help ensure that the winding of the first non-embedded wire sub-portion and the second non-embedded wire sub-portion around each other can be maintained from the rotation position until the exit point is formed. It should be understood that clamping the second non-embedded wire sub-portion so that it can slide means that when the two non-embedded wire sub-portions rotate and twist around each other and generate tension in the wire sub-portion, at the clamping position, the second non-embedded wire sub-portion is pulled through the clamp by tension. In other words, the second non-embedded wire sub-portion is clamped so that the second non-embedded wire sub-portion is allowed to be pulled through the clamp when the sub-wire portion is pulled. It has been found that this helps the wire below the outer surface of the tube at the exit point instead of the second non-embedded wire sub-portion to break when the wire is rotated. It is currently believed that the reason for this situation may be that the tension in the first non-embedded wire sub-portion will be higher than the tension in the second non-embedded wire sub-portion. The term "such that it can slide" may alternatively be referred to as "such that it is loosely held", ie, allowing the second non-embedded wire sub-portion to be pulled through the clamp when the second non-embedded wire sub-portion is pulled.

[0035] In an alternative variation of this embodiment, the second non-embedded wire sub-portion is clamped at a clamping position in a clamp that secures the second non-embedded wire sub-portion in the clamp. This can be understood as a clamp that does not allow and / or prevents wire slippage.

[0036] In another variation of this embodiment, the rotation position is located in a non-embedded space so that the rotation angle between a straight line extending from the exit point to the rotation position and a tangent line to the exit point in a direction perpendicular to the exit point and the outer surface of the tube is 45 degrees or less.

[0037] This may cause the more thorough fracture of wire, because the angle that the tension force and torsion force act on the wire of embedding from the rotation of non-embedded wire sub-portion and torsion reduces.Further, it can prevent that any embedded wire is pulled out from pipe along with tension force accumulation in wire during production.Alternatively, the rotation angle on the direction perpendicular to exit point and tube outer surface can be 40 degree, 35 degree, 30 degree, 25 degree, 20 degree, 15 degree, 10 degree, 9 degree, 8 degree, 7 degree, 6 degree, 5 degree, 4 degree, 3 degree, 2 degree or 1 degree or less between the straight line extending from exit point to rotational position and exit point tangent line.In another variant of the present embodiment, rotational position can be located on exit point tangent line. Typically, the angle of rotation between the exit point tangent and the straight line extending from the exit point to the rotation position can be 45 degrees, 40 degrees, 35 degrees, 30 degrees, 25 degrees, 20 degrees, 15 degrees, 10 degrees, 9 degrees, 8 degrees, 7 degrees, 6 degrees, 5 degrees, 4 degrees, 3 degrees, 2 degrees or 1 degree or less.Similarly, in the variant of the present embodiment, the angle of rotation and / or the clamping angle between the straight line extending to the rotation position or clamping position respectively and the lateral plane extending through the exit point perpendicular to the exit plane can be 45 degrees, 40 degrees, 35 degrees, 30 degrees, 25 degrees, 20 degrees, 15 degrees, 10 degrees, 9 degrees, 8 degrees, 7 degrees, 6 degrees, 5 degrees, 4 degrees, 3 degrees, 2 degrees or 1 degree or less.This can increase output and reduce the variation of the produced pipe.Alternatively, the angle of rotation can be the angle measured between the exit point tangent and the first non-embedded wire sub-portion extending from the exit point to the rotation position (potentially just before rotating the non-embedded wire sub-portion). The rotational position may be the point at which the first non-embedded wire sub-portion and / or the second non-embedded wire sub-portion is rotated. Alternatively, the rotation angle may be measured between the exit point tangent and a straight line extending from the exit point to the apex of the bend of the non-embedded wire portion after the bend is formed at the rotational position.

[0038] In another variation of this embodiment, the clamping position is located in the embedding space so that the clamping angle between the exit point tangent and a straight line extending from the exit point to the clamping position is 45 degrees or less.

[0039] In another variation of this embodiment, the rotation angle and the clamping angle are equal to or less than 10 degrees.

[0040] In another variation of this embodiment, the rotation location and the clamping location are located outside the working channel tube.

[0041] This can be understood as the rotational position and the clamping position being positioned so that there is a spacing between the tube and the rotational position and the clamping position. This can improve the ease with which the method can be performed, because there are fewer spatial restrictions on the rotational position and the clamping position when located outside the tube.

[0042] In an example of this variant, there is a distance of 0.5 or more but equal to or less than 10 working channel tube outer diameters, measured perpendicularly to the outlet plane, between the outlet plane and the rotation position and between the outlet plane and the clamping position, respectively.

[0043] The rotation position and the clamping position can be located outside the working channel tube, so that there is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more working channel tube outer diameters between the rotation position and the outlet plane of the working channel tube and / or between the clamping position and the outlet plane, that is, the rotation position and the clamping position can be positioned at different distances from the outer surface of the tube. There can be equal to or less than 100, 90, 80, 70, 60, 50, 40, 30, 20, 10 or 5 working channel tube outer diameters between the rotation position and the outlet plane and / or between the clamping position and the outlet plane. For example, there can be equal to or greater than 1 working channel tube outer diameter, but less than 30 working channel tube outer diameters, between the rotation position and the outlet plane and / or between the clamping position and the outlet plane. The distance between the outlet plane and the clamping position and / or the rotation position can be measured perpendicular to the outlet plane. The distance between the clamping position and the exit plane can be defined as the vertical distance between the exit plane and the portion of the clamp closest to the exit plane, and the second non-embedded wire sub-portion is clamped at the clamping position. The distance between the rotation position and the exit plane can be defined as the vertical distance between the exit plane and the point at which the first non-embedded wire sub-portion and the second non-embedded wire sub-portion are rotated. Alternatively, the distance can be defined as the vertical distance between the exit plane and the portion of the first non-embedded wire sub-portion and the second non-embedded wire sub-portion that is rotated at the rotation position that is closest to the exit plane. The distance between the rotation position and the exit plane can be defined as the vertical distance between the exit plane and the portion of the device (such as a clamp, hook or loop, etc.) for rotating the first non-embedded wire sub-portion and the second non-embedded wire sub-portion at the rotation position that is closest to the exit plane.

[0044] In another variation of this embodiment, a second non-embedded wire portion of the wire coil extends out of the outer surface of the tube from a different second exit point defining a respective non-embedded direction and an embedded direction, wherein steps C) to G) are performed separately for the second non-embedded wire portion.

[0045] In this way, if there are two non-embedded wire portions extending from the outer surface of the working channel tube (e.g., one at each end of the wire coil), then both wire portions can be broken in the same way to effectively provide a reinforced working channel tube according to the present disclosure.

[0046] In another variation of this embodiment, the working channel tube is secured such that there is a fixed position within 10 working channel tube outer diameters or less proximal to the respective exit points and a fixed position within 10 working channel tube outer diameters or less distal to the respective exit points.

[0047] In a variation of this embodiment, the rod is inserted into the working channel tube before the working channel tube is secured in place.

[0048] This may be done to prevent the tube from being damaged or collapsed when being clamped. The rod may further provide rigidity to the working channel tube when the wire is rotated, which may aid in the wire breaking process and prevent damage to the working channel tube. The rod may be made of a rigid material (e.g., plastic or metal). In an example of this variation, a metal rod is inserted into the working channel tube before it is press-fitted into seven U-shaped press-fit retainers at seven different locations along the working channel tube.

[0049] In the example of this variant, the rod is inserted at least to a certain length so that it extends inside the working channel tube at each location where the working channel tube is fixed and / or at each exit point.

[0050] In another variation on this embodiment, the embedded wire coil extends equal to or less than three quarters of the length of the working channel tube.

[0051] In this way, a working channel tube can be provided, which is strengthened in a specific part of the tube that may be expected to be strengthened. Further, this can reduce the cost of the strengthened working channel tube, because less wire coils need to be used compared to the greater length or the entire length of the strengthening tube, and equally importantly, a more sustainable product can be provided using less material. In a variant of this embodiment, the wire coil can extend 7 / 10, 3 / 5, 1 / 2, 2 / 5, 3 / 10, 1 / 5 or 1 / 10 of the length of the working channel tube that is equal to or less than. In an alternative embodiment, the wire coil can extend over three quarters of the length of the working channel tube, up to and equal to the entire length of the working channel tube that can potentially be strengthened. It should be understood that the working channel tube strengthened by the method can be a working channel tube that is fully strengthened, i.e. strengthened over its entire length, or the working channel tube is strengthened only in one or more sections, strengthened only on a portion of its entire length, i.e. only partially strengthened. A section can be a portion of the full length of the tube, such as extending substantially only along the length of the curved section of the assembled endoscope. For example, when assembled in an endoscope, the working channel tube may be reinforced, for example, only along the length of the curved section. In other words, the wire coil may be arranged only along the curved section of the working channel tube that is located in the assembled endoscope.

[0052] In another variation of this embodiment, at least an outer layer of the working channel wall is made of a plastic material.

[0053] In another variation of the present embodiment, the wall of the working channel tube can be a single layer material or can include two or more layers of material, such as an inner layer and an outer layer. The working channel tube can include an outer layer and an inner layer, the outer layer including an outer surface, and the inner layer having an inner surface. The material of the outer layer can be different from the material of the inner layer. When the two layers, i.e., the outer layer and the inner layer are made of different materials, each layer can be optimized for its specific purpose. The outer layer can be made of a fusible plastic material, which is configured to melt or soften when it is heated, so that, for example, the hot wire of the reinforcing wire coil heated when the working channel tube is produced and strengthened melts or softens the outer layer when it is wound on the working channel tube and cuts into the outer layer, thereby allowing the working channel tube to be strengthened. The inner layer can be made of a fusible plastic material, but it is not necessarily made of a fusible plastic material, because the inner layer is not intended to be melted or softened. The inner layer and therefore its material can be optimized for other purposes, such as enabling the instrument to slide smoothly inside the working channel tube. The outer layer may be made of TPU (thermoplastic polyurethane), for example. The inner layer may be made of HDPE (high density polyethylene). The reinforcing wire coil may be embedded in only one of the layers or in more than one of the layers or in all of the layers. The working channel tube may also be an integral part made of only one meltable plastic material, thus not including an outer layer and an inner layer made of different materials.

[0054] Optionally, a primer may be provided between the inner layer and the outer layer to ensure and increase adhesion between the two layers. For example, advantageously, the outer layer is made of TPU (thermoplastic polyurethane) and the inner layer is made of HDPE (high density polyethylene). The working channel tube may be coextruded so that the inner layer, the tie or primer and the outer layer are extruded simultaneously.

[0055] In another variation of this embodiment, the outer diameter of the working channel tube can be equal to or less than 15mm, 14mm, 13mm, 12mm, 11mm, 10mm, 9mm, 8mm, 7mm, 6mm, 5.5mm, 5mm, 4.5mm, 4mm, 3.5mm or 3mm. The outer diameter of the working channel tube can be, for example, in the range of 1.5mm to 10mm. The wall thickness of the working channel tube, i.e., the radial thickness of the material between the outer surface and the inner surface of the working channel tube, can be equal to or less than 1.5mm, 1.4mm, 1.3mm, 1.2mm, 1.1mm, 1mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm or 0.5mm. The wall thickness can be, for example, in the range of 0.1mm to 0.7mm. This can provide the best compromise between the working channel diameter (i.e., the diameter of the hollow channel extending through the working channel tube), the outer diameter of the working channel tube, the bending performance and durability.

[0056] The inner layer can be thinner than the outer layer, or in other words, the wall thickness of the inner layer can be less than the wall thickness of the outer layer. For example, the inner layer can have a thickness between 0.050 mm and 0.080 mm, while the outer layer can have a thickness between 0.32 mm and 0.35 mm. However, other layer thicknesses are contemplated, and it is also contemplated that the thickness of the inner layer is greater than the thickness of the outer layer. The working channel wall can have a wall thickness of less than 0.5 mm, or less than 0.4 mm.

[0057] In another variation of this embodiment, the diameter of the wire reinforcing the wire coil can be equal to or less than 0.5mm, 0.45mm, 0.4mm, 0.35mm, 0.3mm, 0.25mm, 0.2mm, 0.153mm, 0.15mm, 0.128mm, 0.102mm, 0.10mm, 0.08mm or 0.05mm. The diameter of the wire can be, for example, in the range of 0.01mm to 0.25mm or 0.05mm to 0.15mm. The diameter of the wire can be between 0.08mm and 0.15mm. In the example of this variation, the outer diameter of the working channel tube is 5.4mm, the wall thickness is 0.5mm and the diameter of the wire is 0.15mm. The diameter of the wire can alternatively be the thickness of the wire.

[0058] The working channel tube may have a wall thickness of less than 0.4 mm and may include an inner layer having a thickness between 0.050 mm and 0.080 mm, an outer layer having a thickness between 0.32 mm and 0.35 mm, and a coil having a coil pitch between 0.5 mm and 1.5 mm, or between 0.8 mm and 1.2 mm, or about 1.0 mm. The wall thickness of the working channel tube may be at least twice the diameter or thickness of the wire.

[0059] In another variation of this embodiment, the wire reinforcing the wire coil may be a single strand wire. The wire may be made of a ductile material. The wire may be a metal wire, for example, the wire may be made of SUS 304. In an example of this variation, the wall of the working channel tube includes two layers in the form of an inner layer and an outer layer, and the working channel tube has an outer diameter of 3.65 mm and a wall thickness of 0.39 mm, the wire has a diameter of 0.10 mm SUS 304, and it is embedded in the outer layer of the tube wall.

[0060] In another variation of this embodiment, a reinforced working channel tube may be provided with several sections having embedded wire coils, and b) to g) may be repeated for each section of embedded wire coils to provide a reinforced working channel tube comprising several reinforced sections.

[0061] In a second aspect, a working channel tube produced according to the method of the first aspect is disclosed.

[0062] In a third aspect, an endoscope comprising a reinforced working channel tube according to the second aspect is disclosed.

[0063] In a fourth aspect, a system is provided comprising a video processing apparatus and an endoscope according to the third aspect, wherein it is disclosed that the video processing apparatus (VPA) is connectable to the endoscope and is capable of processing images recorded by the endoscope and outputting the images on a display.

[0064] In a variation of this embodiment of the fourth aspect, the video processing device may include a built-in display for displaying images output by the VPA.The VPA may be connectable to the endoscope wirelessly or via a wired connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The disclosure will now be made in more detail based on non-limiting exemplary embodiments and with reference to the accompanying drawings, in which:

[0066] Figure 1 A schematic diagram of a visualization system including an endoscope and a video processing device according to the present disclosure is shown.

[0067] Figure 2 is a side view of a curved section showing the working channel tube.

[0068] Figure 3 yes Figure 2 Section AA of the curved segment.

[0069] Figure 4 A flow chart of a method for producing a reinforced working channel tube according to the present disclosure is shown.

[0070] Figure 5 Shown is a side view of a working channel tube in a wire breaking machine during production according to the method of the present disclosure.

[0071] Figure 6 Shows Figure 5 Close-up of BB with details in it.

[0072] Figure 7 Shown is a schematic illustration of a working channel tube viewed parallel to the longitudinal axis of the tube during production according to another variation of the method of the present disclosure.

[0073] Figure 8 The non-embedded wire sub-portion is shown in a state where it has been rotated a certain amount. Figure 7 Schematic illustration of the same view.

[0074] Fig. 9 From Figure 7 and Figure 8 Another variation of the method according to the present disclosure is shown from the same advantageous position in FIG.

[0075] Fig.10 A schematically illustrated top view of a working channel tube during production according to another variant of the method according to the present disclosure is shown.

[0076] Fig.11 A cross section of a working channel tube according to an embodiment of the present disclosure is shown.

[0077] Fig.12 A longitudinal cross-sectional view of a working channel tube according to the present disclosure is shown.

[0078] The drawings are schematic in nature and are only useful for understanding the present disclosure. Features of different embodiments may be interchanged with each other. DETAILED DESCRIPTION

[0079] Figure 1 1 is a schematic side view of a visualization system 100, which includes an endoscope 2 having a cable connector 106 that can be connected to an endoscope connection port (not shown) of a video processing apparatus (VPA) 102. The VPA can include a display screen 104, or as shown, can be connected to a "detachable" display screen. As known in the art, the VPA can be communicatively connected to the detachable display screen 104 via Ethernet, wireless, AVI, HDMI or other data interface. When the endoscope is connected, the VPA presents an image or video stream through the display screen, as known in the art. The endoscope 2 has a proximal endoscope handle 4 and an insertion line 6 extending distally from the endoscope handle 4. The insertion line 6 is configured to be inserted into a body cavity of a patient and includes an insertion tube 8, an actively bendable bending section 10, and a distal tip unit 12. The endoscope 2 further includes a working channel 14 that extends from a working channel access port 16 disposed at the endoscope handle 4 to the distal tip unit 12. The working channel 14 includes a working channel tube 18, which is arranged inside the endoscope handle 4, the insertion tube 8 and the bending section 10. The endoscope handle 4 includes two operating units 20, 22, which are formed as wheels for manipulating the bending section 10 of the insertion line 6. In particular, the user can apply a rotational force to both the first operating unit 20 and the second operating unit 22 to bend the bending section 10 in two bending planes, i.e. in four directions. The endoscope 2 can alternatively be formed as a single-plane bending endoscope, which can only bend in two, preferably opposite directions and has only one operating unit 20, 22. In addition to the wheel, the operating unit may include a lever well known in the art. The endoscope may be a disposable endoscope.

[0080] Figure 2An embodiment of a curved section 10 is shown, showing the working channel tube 18 (reinforcement members not shown). Figure 3 yes Figure 2 AA of the curved section of the embodiment of the present invention, showing the gap 70 in which the working channel tube 18 is positioned. The curved section 10 may include a single-piece polymer structure including a plurality of segments 60 interconnected by polymer strips 62 or hinges, the plurality of segments forming part of the one-piece structure and bending when the control cable 64 is tensioned by operation of the operating unit 20. The working channel 14 may be configured to introduce surgical tools therethrough. Figure 3 6, the wall of the segment 60 defines a space 70 and a plurality of cutout lobes 72 extending from the periphery of the inner surface of the segment 60, through which the control cable guide tube 66 and the control cable 64 pass. A sleeve (not shown) may be provided on the curved segment 10 to fluidically seal the space between adjacent segments 60. The wire 68 passes through one of the cutout lobes 72 and connects the camera positioned in the distal end of the insertion wire 6 to the handle 4. The cable having the cable connector 106 connects the wire 68 to the handle 4. Figure 1 VPA 102 shown. As can be imagined, the space in the curved section is limited and becomes even more limited as the diameter of the insertion wire 6 is reduced to minimize the invasiveness of the surgical procedure using the endoscope 2. These reductions require a smaller working channel tube with a smaller wall thickness, and the working channel tube with a reduced wall thickness benefits from the disclosed reinforcement. Any protrusions from the outer surface of the working channel tube (such as the wire from the reinforcing wire coil) will reduce the benefits obtained by using a working channel tube with a smaller wall thickness, because the protrusions will occupy some or all of the space saved by using a working channel tube with a smaller wall thickness. In addition, such protrusions can generate additional friction and resistance to bending and manipulating the endoscope, especially if they contact the inner surface of the insertion tube 8 and get stuck on it. If other fluid tubes are set inside the insertion tube, especially if they are made of plastic, as is usually possible, such protrusions may get stuck on these fluid tubes, damage or even pierce these fluid tubes. Therefore, any such protrusions should preferably be avoided.

[0081] The working channel tube 18 disposed inside the endoscope handle 4, the insertion tube 8, and the bending section 10 is a specific reinforced working channel tube 18 according to the present disclosure, and is particularly reinforced in the portion of the working channel tube 18 disposed inside the bending section 10, so as to prevent kinking of the working channel tube 18 when the bending section 10 is bent. It should be understood that it is also conceivable to reinforce the entire working channel tube 18, that is, to reinforce not only the portion of the working channel tube 18 disposed inside the bending section 10 of the insertion line 6 but also other portions of the working channel tube 18. Further, it should be understood that the working channel tube 18 does not need to be disposed inside the insertion line 6, but may also be alternatively attached to the insertion line 6 from the outside.

[0082] refer to Figures 4 to 10 , a method for producing a wire coil reinforced working channel tube 18 for an endoscope according to the present disclosure will be described. Figure 4 A flow chart of a method for producing a reinforced working channel tube 18 is shown. In a first step S1, a working channel tube 18 reinforced with a wire coil 33 is provided, the wire coil being embedded between the inner surface 26 and the outer surface 28 of the working channel tube. A non-embedded wire portion 30 of the wire coil 33 extends out of the outer surface 28 of the tube 18 from an exit point 29, and an exit point tangent line 34 tangential to the outer surface 28 at the exit point 29 defines two opposite directions extending away from the exit point 29, namely a non-embedded direction UD extending away from a final embedded wire portion 35 leading to the exit point 29, and an embedded direction ED opposite to the non-embedded direction UD, as for example Figure 7 Further, the outlet plane 36 extends through the outlet point 29 and the longitudinal axis L of the tube 18, and the space extending from the outlet plane in the non-embedded direction and the embedded direction is defined as the non-embedded space and the embedded space, respectively.

[0083] In step S2, the working channel tube 18 is fixed. Then, in step S3, the non-embedded wire portion 30 is extended from the exit point 29 to a rotational position 40 in the non-embedded space. In a further step S4, the non-embedded wire portion 30 is bent at the rotational position 40, thereby forming a bend 41 and a first non-embedded wire sub-portion 31 extending from the exit point 29 to the bend 41 and a second non-embedded wire sub-portion 32 extending after the bend 41. In step S5, the second non-embedded wire sub-portion 32 is extended back across the working channel tube 18 to a clamping position 42 located in the embedded space. In step S6, the second non-embedded wire sub-portion 32 is clamped at the clamping position 42 in a clamp that is configured to allow the wire 32 to slide so that a length of the wire slides out of the clamp when pulled. In step S7, non-embedded wire sub-portions 31, 32 are rotated at rotational position 40 such that first non-embedded wire sub-portion 31 and second non-embedded wire sub-portion 32 are twisted around each other until the wire breaks (eg, Figure 8 ). The order of the steps described herein is merely one example within the scope of the present disclosure. In other variations of this embodiment, the order may be different, for example, the non-embedded wire portion 30 may be bent before it is extended to the rotational position 40, the second non-embedded wire sub-portion 32 may be extended across the tube 18 to the clamping position 42 and potentially clamped at the clamping position, after which the non-embedded wire portion 30 is extended to the rotational position 40, and the working channel tube 18 may be fixed after the non-embedded wire portion 30 has been bent at the rotational position 40 and / or after the second non-embedded wire sub-portion 32 has been clamped at the clamping position 42.

[0084] As also mentioned in the Summary of the Invention section, the wire coil reinforced working channel tube 18 can be provided in a variety of sensible ways known to those skilled in the art. In this example, it is provided by providing a working channel tube made of a plastic material, softening the outer surface 28 of the tube 18 by heat, and spirally winding a wire 38 into the outer surface of the tube to form a wire coil 33 embedded in the tube 18 and the working channel tube.

[0085] Figure 5 and Figure 6 A wire coil reinforced working channel tube 18 in a wire breaking machine during production is shown. Before fixing the tube 18, a rigid metal rod 80 has been inserted into the tube 18. Then, the working channel tube 18 has been fixed so that translational and rotational movement is prevented by press-fitting it into 7 U-shaped press-fit retainers 81 at 7 different fixed positions 81 along the working channel tube 18. The metal rod 80 extends inside the working channel tube at each position 81 where the working channel tube 18 is fixed and at each exit point 29. There are fixed positions 81 within 5 working channel tube outer diameters D proximal and distal to each respective exit point 29. Two non-embedded wire portions 30 (one at each end of the wire coil 33) have been extended from their respective exit points 29 to respective rotational positions 40 located in the non-embedded space and including hooks 51, around which they have been bent to form bends 41 and respective first non-embedded wire sub-portions 31 and second non-embedded wire sub-portions 32. Instead of hook 51, any other suitable geometry may be used, for example the rotational position may include a loop (not shown) through which the non-embedded wire portion 30 may be passed and bent around the loop, thereby forming the bend 41, similar to Figure 5 and Figure 6 The non-embedded wire is bent around the hook 51. Alternatively, instead of a hook or loop, the rotation position may include a clamp 52 (such as Figures 7 to 10), wherein the non-embedded wire portion 30 is bent inside a clamp 52, which then clamps the first non-embedded wire sub-portion 31 and the second non-embedded wire sub-portion 32 in place, after which they are rotated with the help of the attached electric motor 44.

[0086] After bending around hook 51, second non-embedded wire sub-portion 32 has extended back across tube 18 on the same portion of tube 18 where corresponding exit point 29 is located, and through the space perpendicular to corresponding exit point 29 to reach corresponding clamping position 42 in the embedding space. Second non-embedded wire sub-portion 32 has been clamped at corresponding clamping position 42 in clamps 43, which are configured to allow wire 32 to slip, so that when first non-embedded wire sub-portion 31 and second non-embedded wire sub-portion 32 are rotated, the length of second non-embedded wire sub-portion 32 can slide out of clamps 43 due to the pulling force on wire 32 generated by the rotation and twisting of first non-embedded wire sub-portion 31 and second non-embedded wire sub-portion 32. In other words, second non-embedded wire sub-portion 32 can be said to be loosely clamped. This can be achieved by low clamping force and / or low friction or a combination thereof. After clamping the second non-embedded wire sub-portion 32, the corresponding first non-embedded wire sub-portion 31 and the second non-embedded wire sub-portion 32 are then rotated at the rotational position by rotating the hook 51 driven by the electric motor 44, whereby the wires 31, 32 are twisted around each other until the wires break. That is, steps S3 to S8 are repeated for the two non-embedded wire portions, respectively. Figure 8 The twisting of the first non-embedded wire sub-portion 31 and the second non-embedded wire sub-portion 32 about each other after several rotations is schematically shown. In the illustrated embodiment, there is a distance R, C of 0.5 or more but equal to or less than 10 working channel tube outer diameters D between the exit plane 36 and the rotation position 40 and between the exit plane 36 and the clamping position 42, respectively, the distance being measured perpendicular to the exit plane 36. This Figure 7 It can be best seen in that the distance R between the outlet plane 36 and the portion of the clamp 52 closest to the outlet plane 36 is greater than 0.5 but less than one working channel tube outer diameter D, and the distance C between the outlet plane 36 and the portion of the clamp 43 closest to the outlet plane is close to one working channel tube outer diameter D.

[0087] As in Figure 5 As can be seen in detail BB, the non-embedded wire portion toward the proximal end of the working channel tube 18 extends substantially tangentially to the outer surface of the working channel tube 18, of which only the second non-embedded portion 32 is visible. As can also be seen, this is not the case for the first non-embedded wire sub-portion 31 toward the distal end of the working channel tube 18 in detail BB. Figure 6 yes Figure 58 is an enlarged view of detail BB in which some of the press fit retainer 81 has been hidden for clarity. It can be seen here that the rotational position 40 is positioned at an angle Ar with the exit point tangent 34, and similarly, the clamping position 42 is positioned at a clamping angle Ac with the exit point tangent 34. The rotational angle Ar and the clamping angle Ac are both less than 25 degrees. In addition, the bend 41, the exit point 29 and the clamping position 42 can be seen.

[0088] exist Figure 7 and Figure 8 In the embodiment of the present invention, the rotation position 40 and the clamping position 42 are substantially located on the exit point tangent line 34. However, this does not necessarily mean that the reference Fig. 9 and Fig.10 As explained. Fig. 9 As shown, the rotation position 40 can be positioned so that the rotation angle Ar between the exit point tangent line 34 and the straight line 53 extending from the exit point 29 to the rotation position 40 at right angles to the tube outer surface 28 is 45 degrees or less, in this case about 30 degrees or less. The rotation angle Ar is generally preferably 45 degrees or less. The same is true for the clamping angle Ac between the exit point tangent line 34 and the straight line 54 extending between the exit point 29 and the clamping position 42, which is about 30 degrees or less. Fig. 9 30 degrees or less, but in the opposite direction of the exit point tangent line 34 compared to the rotation angle Ar. However, in other embodiments, the rotation angle Ar may also be in the direction of the exit point tangent line 34. Fig. 9 In fact, both the rotation angle Ar and the clamping angle Ac can extend in any direction from the exit point tangent line 34, such as in a lateral direction away from the lateral plane 55, which extends perpendicular to the exit plane 36 through the exit point 29, as shown in FIG. Fig.10 Preferably, the rotation angle Ar and the clamping angle Ac are equal to or less than 45 degrees, such as shown in the figure.

[0089] Fig.11A cross section of a working channel tube 18 according to an embodiment of the present disclosure is shown. The working channel tube 18 has a circular cross section and includes two layers, an outer layer 46 and an inner layer 48. The outer layer 46 and the inner layer 48 are both substantially hollow elongated tube bodies and are preferably made of different materials. The outer layer 46 is directly arranged around the inner layer 48, or in other words, the inner layer 48 is inserted into the outer layer 46. A primer 50 can be provided between the outer layer 46 and the inner layer 48 to ensure adhesion between the outer layer 46 and the inner layer 48. For example, the outer layer 46 can be made of thermoplastic polyurethane (TPU), and the inner layer 48 can be made of high-density polyethylene (HDPE). These layers can be co-extruded. T1 represents the wall thickness. T2 represents the inner layer thickness. T3 represents the outer layer thickness. The outer surface 28 is smooth, without protrusions, etc.

[0090] Fig.11 The embodiment shown in is only an example, and it is obvious that it may also be advantageous that the working channel tube 18 is not made of two parts (outer layer 46 and inner layer 48), but is made of an integral elongated working channel tube part, which has an outer surface 28 and an inner surface 26 and is made of a meltable plastic material.

[0091] Fig.12 2 shows an embodiment according to which the working channel tube 18 is made from one integral part. Fig.12 A longitudinal cross-sectional view of a working channel tube 18 is shown having a coil 33 embedded in the working channel tube 18. The wire 38 forming the coil 33 is covered by the material of the working channel tube 18 and is therefore not exposed to the outside (not visible from the outside).

[0092] According to another embodiment, the working channel tube 18 may have an outer diameter of 5.4±0.076 mm, an inner diameter of 4.4±0.076 mm, and a wall thickness of 0.5 mm. The total length of the working channel tube 18 may be 1,500. The working channel tube 18 may include an outer layer 46, an inner layer 48, and a primer 50, which may also be referred to as a bonding layer, disposed between the outer layer 46 and the inner layer 48, such as Fig.11 According to a particularly preferred embodiment, the material of the outer layer 46 may be a thermoplastic polyurethane with additives, such as 2363-90AE. For example, the outer layer 46 may contain 70% 2363-90AE and 30% additives. Among the additives, it may be preferred that the outer layer 46 includes an antimicrobial additive (such as BaSo4) and a friction reducing additive (such as ). The material of the inner layer 48 can be high-density polyethylene, such as Borealis HE9621-PH. The material of the primer 50 or the bonding layer may be a linear low-density polyethylene-based bonding resin, such as 18300M.

[0093] In the present embodiment, the wire of the wire coil has an outer diameter of 0.15 mm and is made of stainless steel SUS304 including a Br—Ni—Co coating.

[0094] The pitch of the coil 33 formed by winding the wire of the wire coil is 1 mm, and the length of the section of the working channel tube 18 reinforced by the coil 33 is 115±5 mm. The section reinforced by the coil 32 has an inner diameter greater than 4.2 mm and an outer diameter less than 5.4 mm.

[0095] The present disclosure has been described with reference to exemplary embodiments. However, the scope of the present invention is not limited to the illustrated embodiments, and variations and modifications may be implemented without departing from the scope of the present invention.

[0096] Throughout the description, the use of the terms "first," "second," etc. does not imply any particular order or importance, but is included to identify a single element. Furthermore, reference to a first element does not imply the presence of a second element and vice versa.

[0097] List of Reference Numerals

[0098] 2 Endoscope

[0099] 4 Endoscope handle

[0100] 6 Insert line

[0101] 8 Insertion tube

[0102] 10 Bending section

[0103] 12 Distal terminal unit

[0104] 14 Working channels

[0105] 16 Working channel access port

[0106] 18 Working channel tube

[0107] 20 First operating unit

[0108] 22 Second operating unit

[0109] 25 Working channel wall

[0110] 26 Inner surface

[0111] 28 External surface

[0112] 29 Exit Point

[0113] 30 Non-embedded wire part

[0114] 31 first non-embedded wire sub-portion

[0115] 32 Second non-embedded wire sub-portion

[0116] 33 Wire Coil

[0117] 34 Exit point tangent

[0118] 35 Final embedding of wire part

[0119] 36 Exit plane

[0120] 38 Wire Coil Wire

[0121] 40 Rotational positions

[0122] 41 Bend

[0123] 42 Clamping position

[0124] 43 Fixture

[0125] 44 Rotator

[0126] 46 Outer layer

[0127] 48 Inner layer

[0128] 50 Primer

[0129] 51 Hook

[0130] 52 Clamp

[0131] 53 Straight line between exit point and rotation position

[0132] 54 Straight line between exit point and clamping position

[0133] 55 Lateral plane

[0134] 60 segments

[0135] 62 Hinge

[0136] 64 Control Cable

[0137] 66 Control cable guide

[0138] 68 Wire

[0139] 70 Interval

[0140] 72 Notch convex corner

[0141] 80 shots

[0142] 81 Press-fit retainer

[0143] 100 Visualization System

[0144] 102 Video processing device

[0145] 104 Display

[0146] 106 Cable Connector

[0147] T1 Wall thickness

[0148] T2 inner layer thickness

[0149] T3 outer layer thickness

[0150] L Longitudinal axis

[0151] Ar rotation angle

[0152] Ac Clamping Angle

[0153] UD Non-embedded direction

[0154] ED embedding direction

[0155] D Working channel outer diameter

[0156] R Distance between the exit plane and the rotation position

[0157] C Distance between the exit plane and the clamping position.

Claims

1. A method for producing a wire coil reinforced working channel tube for an endoscope, the method comprising: a) providing a working channel tube reinforced with a wire coil embedded between an inner surface and an outer surface of the working channel tube, wherein a non-embedded wire portion of the wire coil extends out of the outer surface of the tube from an exit point, wherein an exit point tangent line tangent to the outer surface at the exit point defines two opposite directions extending away from the exit point: i. a non-embedded direction extending away from the final embedded wire portion leading to the exit point; and ii. an embedding direction opposite to the non-embedding direction; wherein an outlet plane extends through the outlet point and the longitudinal axis of the tube, and spaces extending from the outlet plane along the non-embedded direction and the embedded direction are defined as non-embedded space and embedded space, respectively; b) fixing the working channel tube; c) extending the non-embedded wire portion from the exit point to a rotational position within the non-embedded space; d) bending the non-embedded wire portion at the rotational position, thereby forming a bend and a first non-embedded wire sub-portion extending from the exit point to the bend and a second non-embedded wire sub-portion extending after the bend; e) extending the second non-embedded wire sub-portion back across the tube to a clamping position within the embedment space; f) clamping the second non-embedded wire sub-portion at the clamping location in a clamp; and g) rotating the non-embedded wire sub-portion at the rotational position such that the first non-embedded wire sub-portion and the second non-embedded wire sub-portion twist around each other until the wire breaks.

2. The method according to claim 1, wherein: The clamp in which the second non-embedded wire sub-portion is clamped is configured to allow sliding of the wire such that a length of the wire slides out of the clamp when pulled.

3. A method according to any one of the preceding claims, wherein: The rotation position is located in the non-embedded space so that a rotation angle between a straight line extending from the exit point to the rotation position and a tangent line to the exit point in a direction perpendicular to the exit point and the outer surface of the tube is 45 degrees or less.

4. The method according to claim 1 or 2, wherein: The clamping position is located in the embedding space so that a clamping angle between a tangent line to the exit point and a straight line extending from the exit point to the clamping position is 45 degrees or less.

5. The method according to claim 4, wherein: The rotation angle and the clamping angle are equal to or less than 10 degrees.

6. The method according to claim 1 or 2, wherein: There is a distance of 0.5 or more but equal to or less than 10 working channel tube outer diameters between the outlet plane and the rotational position and between the outlet plane and the clamping position, respectively, the distance being measured perpendicular to the outlet plane.

7. The method according to claim 1 or 2, wherein: A second non-embedded wire portion of the wire coil extends out of the outer surface of the tube from a second different exit point defining a respective non-embedded direction and an embedded direction, wherein steps C) to G) are respectively performed for the second non-embedded wire portion.

8. The method according to claim 1 or 2, wherein: The working channel tube is secured so that there is a fixed position within 10 working channel tube outer diameters or less proximal to each respective exit point and a fixed position within 10 working channel tube outer diameters or less distal to each respective exit point.

9. The method according to claim 1 or 2, wherein: Prior to securing the working channel tube in place, a rod is inserted into the working channel tube.

10. The method according to claim 9, wherein: The rod is inserted at least to a certain length so that the rod extends inside the working channel tube at each position where the working channel tube is fixed and / or at each exit point.

11. The method according to any one of claims 1 or 2, wherein: The embedded wire coil extends equal to or less than three quarters of the length of the working channel tube.

12. The method according to claim 1 or 2, wherein: At least the outer layer of the working channel tube is made of plastic material.

13. A reinforced working channel tube produced according to the method of any one of claims 1 to 12.

14. An endoscope comprising the reinforced working channel tube according to claim 13.

15. A visualization system comprising a video processing device and an endoscope according to claim 14, wherein: The video processing apparatus (VPA) can be coupled to the endoscope and can process images recorded by the endoscope and output the images on a display.

Images