JP5371706B2 - Endoscopic flexible tube and method for manufacturing the endoscopic flexible tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope flexible tube having excellent flexibility and repulsion properties without damaging durability. <P>SOLUTION: A flexible tube part 5 includes: braids 61 formed by braiding a plurality of wires 61s; and a resin skin 60 covered with the braids 61. The wires 61s are positioned so as to be movable with respect to the resin skin 60. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a flexible tube for an endoscope comprising a reticulated tube formed by braiding a plurality of strands, and a sheath resin coated on the reticulated tube, and the manufacture of the flexible tube for an endoscope Regarding the method.

  As is well known, an endoscope flexible tube (hereinafter simply referred to as a flexible tube) is a spiral tube (hereinafter referred to as a flex) made of a steel plate serving as a core material, and a metal mesh tube (hereinafter referred to as a flex tube). The outer cover resin made of a thermoplastic resin such as polyurethane, for example, is coated on the coated serpentine tube formed by coating a blade).

  In addition, since the shrinkage rate of the outer shell resin is large after molding, the outer shell resin is fixed to the coated snake tube, specifically, the blade and the flex by tightening the blade with the outer shell resin after molding. However, normally, in order to improve the durability of the flexible tube, the outer resin is firmly fixed to the coated snake tube via an adhesive or the like. This is because if the outer resin is peeled from the coated snake tube, the flexible tube is easily broken at the peeled portion.

  Further, as a configuration for firmly fixing the outer resin to the coated snake tube, for example, Patent Document 1 discloses that the braid density of the wire bundle for braiding the blade is 0.78 in order to improve the binding force of the blade to the outer resin. A configuration in which the blade is braided in a range of 0.90 or less is disclosed.

  Further, in Patent Document 2, in order to prevent the outer resin from peeling off from the blade, a part of the strand bundle that braids the blade is coated with a resin that is highly compatible with the outer resin, so that the blade is coated. A configuration is disclosed in which the coated resin is melted and bonded to the outer resin.

  Further, in Patent Document 3, in order to improve the welding power of the outer skin resin to the blade, a resin having high compatibility with the outer skin resin is applied to the blade, so that the resin applied to the blade is melted and bonded to the outer skin resin. A configuration is disclosed.

  In addition, a configuration in which the outer resin is firmly fixed to the blade by allowing the outer resin to penetrate between the strands braiding the blade is also well known.

JP-A-9-51870 Japanese Patent Laid-Open No. 10-127572 Japanese Patent Laid-Open No. 8-171059

  However, if the outer sheath resin is firmly fixed to the coated snake tube, there is an advantage that the outer sheath resin is difficult to peel off, but the movement of the blade strands is restricted. There is a problem that the flexibility cannot be sufficiently obtained, the flexible tube becomes hard, and the elasticity (rebound resilience) of the flexible tube cannot be obtained sufficiently.

  Further, in addition to these problems, as described above, there is a problem that the flexibility of the flexible tube is further lowered when the blade is tightened by the molded outer resin.

  The present invention has been made in view of the above-described problems, and is a flexible tube for an endoscope excellent in flexibility and elasticity without impairing durability, and manufacturing the flexible tube for an endoscope. It aims to provide a method.

In order to achieve the above object, an endoscope flexible tube according to an aspect of the present invention includes a mesh tube formed by braiding a plurality of strands, and an inner resin coated with the mesh tube. A flexible tube for an endoscope, wherein a gap is formed between the element wire and the outer resin, and the element wire is positioned so as to be movable with respect to the outer resin by the gap. The

In addition, a method of manufacturing a flexible tube for an endoscope according to an aspect of the present invention includes a mesh tube forming step of forming a mesh tube by braiding a plurality of strands, and a core material after the mesh tube forming step. A mesh tube coating step for coating the mesh tube, and a sheath resin coating step for coating the sheath resin while applying heat to the mesh tube so that the mesh tube is movable with respect to the sheath resin, And the outer resin is fixed only to the core material in the outer resin coating step.

  According to the present invention, it is possible to provide an endoscope flexible tube excellent in flexibility and elasticity without impairing durability, and a method for manufacturing the endoscope flexible tube.

Partial plan view of an endoscope having a flexible tube for an endoscope according to the present embodiment Partial sectional view of the insertion portion of the endoscope of FIG. The fragmentary sectional view which expands and shows the structure of the flexible tube part of FIG. Partial sectional view of the flexible tube taken along line IV-IV in FIG. The fragmentary sectional view of the flexible tube part which shows the state before cooling after coat | covering the outer periphery resin of the braid | blade of FIG. Partial sectional view of the flexible tube part of the second embodiment The fragmentary sectional view of the flexible tube part which shows the state before cooling after coat | covering the outer periphery resin on the outer periphery of the braid | blade of 2nd Embodiment Partial sectional view of the flexible tube portion of the third embodiment The fragmentary sectional view of the flexible tube part which shows the state before cooling after coat | covering outer skin resin on the outer periphery of the braid | blade of 3rd Embodiment, and coating this outer shell resin

Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1 is a partial plan view of an endoscope provided with a flexible tube for an endoscope according to the present embodiment, and FIG. 2 is a partial cross-sectional view of an insertion portion of the endoscope of FIG.

  As shown in FIG. 1, an endoscope 1 includes an elongated insertion portion 2 to be inserted into a test site, and a proximal end side (hereinafter referred to simply as an insertion direction) of the insertion portion 2 (hereinafter referred to simply as an insertion direction). The main part is composed of an operation unit 6 connected to the base end side) and a universal cord 7 extending from the operation unit 6 and connected to a main body (not shown) for controlling the endoscope 1. It is configured.

  The insertion portion 2 is curved in four directions, for example, up and down, left and right, which are located in the proximal end side relative to the distal end portion 3 in order from the distal end side in the insertion direction (hereinafter simply referred to as the distal end side). The main part is composed of a flexible bending portion 4 and a flexible tube portion 5 that is a flexible tube for an endoscope that is located on the proximal end side with respect to the bending portion 4.

  As shown in FIG. 2, the distal end portion 3 is provided with a distal end hard portion 30 made of metal and having a substantially columnar shape. An insulative tip cover 31 is placed so as to cover a part and the outer periphery of the cover.

  The distal end of the bending piece 33 constituting the bending portion 4 is fixed to the outer peripheral surface of the proximal end of the distal end hard portion 30 by brazing or the like, and the outer periphery of the bending piece 33 is bent through the net tube 38 to the bent rubber tube 32. It is covered with. The distal end of the curved rubber tube 32 is fixed to the outer peripheral surface of the distal end hard portion 30 by pincushion bonding or the like.

  A hole penetrating along the insertion direction of the insertion portion 2 is formed in, for example, the approximate center of the distal end hard portion 30, and the imaging unit 200 is provided in the hole.

  The imaging unit 200 includes a plurality of objective lenses 11, and the objective lenses 11 are fixed in a lens frame 10 provided in the hole by an adhesive or the like. A lens frame 12 is fitted and fixed to the inner peripheral surface of the base end side of the lens frame 10, and a plurality of objective lenses 13 are also fixed in the lens frame 12 by an adhesive or the like.

  Further, the inner periphery on the distal end side of the element frame 14 is fitted to the outer periphery on the proximal end side of the lens frame 10, and the cover glass 15 is fixed to the inner periphery on the proximal end side of the element frame 14. . Note that the cover glass 15 protects the imaging surface by being attached to the imaging surface of a solid-state imaging device (hereinafter simply referred to as an imaging device) 17 with an adhesive or the like.

  In addition, an electrical board 18 on which a plurality of electronic components are mounted is electrically connected to the imaging element 17, and each lead wire 20 of the signal cable 19 is electrically connected to the electrical board 18. . The signal cable 19 transmits and receives electrical signals from the apparatus main body described above to the image sensor 17 and is inserted into the insertion unit 2, the operation unit 6, and the universal cord 7.

  Note that a suction hole that sucks fluid near the test site, a hole that illuminates the test site, or a lighting unit that is not shown in the drawing is provided in the distal end hard portion 30 substantially parallel to the hole in which the imaging unit 200 is disposed. An air supply / water supply hole for supplying gas or liquid to the region to be examined is formed, but since it is well known, detailed description thereof is omitted.

  Returning to FIG. 2, the base 16 is fixedly inserted into the suction hole, and the base 16 protrudes rearward in the insertion direction from the proximal end side of the suction hole (hereinafter simply referred to as the rear). The tip of the suction tube 22 is fixed by thread winding bonding or the like.

  Note that the inside of the suction tube 22 constitutes a passage through which fluid flows, and is inserted into the insertion portion 2, the operation portion 6, and the universal cord 7 and is connected to the above-described apparatus main body.

  A plurality of bending pieces 33 constituting the bending portion 4 are arranged in the bending rubber tube 32 of the bending portion 4 along the insertion direction, and each bending piece 33 is made of an adjacent piece and a metal piece. They are connected to each other by rivets or the like so as to be rotatable.

  Of the plurality of bending pieces 33, the bending piece 33 located on the most proximal side is fixed to a connecting member 50 disposed at a boundary position between the bending portion 4 and the flexible tube portion 5. In addition, the base end side of the curved rubber tube 32 is fixed to the outer periphery of the connecting member 50 by thread winding adhesion or the like.

  Also, four bending operation wires 40 (only two are shown in FIG. 2) for bending the bending portion 4 in, for example, four directions, up, down, left and right, are inserted into the insertion portion 2, and the bending operation wires are inserted. The distal end of 40 is fixed to the top / bottom / left / right of the distal end hard portion 30 or the bending piece 33 located on the most distal side, and the rear end of the bending operation wire 40 is provided in the operation portion 6 such as a pulley (not shown). Connected to the traction device.

  The main portion of the flexible tube portion 5 is composed of a flex 62 that is a core material, a blade 61 that is a mesh tube coated on the outer periphery of the flex 62, and a skin resin 60 that is coated on the outer periphery of the blade 61. The inner periphery of the connecting member 50 is fixed to the outer periphery on the tip end side of the blade 61. Further, the outer end of the blade 61 is fixed to the outer periphery of the blade 61 behind the connecting member 50 by pincushion bonding or the like.

  Hereinafter, the detailed structure of the flexible tube part 5 is shown using FIG. 3, FIG. 3 is an enlarged partial cross-sectional view showing the configuration of the flexible tube portion of FIG. 2, and FIG. 4 is a partial cross-sectional view of the flexible tube portion taken along line IV-IV in FIG.

  As shown in FIG. 3, the flexible tube portion 5 has a flex 62 formed by winding an elastic strip-like thin plate material in a spiral shape from the inner peripheral surface side, and a strand 61s covering the flex 62 is knitted. A main part is constituted by a blade 61 formed in a tubular shape and a tubular outer resin 60 formed of a flexible resin member covering the blade 61, for example, a thermoplastic resin such as polyurethane.

  Further, as shown in FIG. 4, each of the plurality of strands 61s constituting the blade 61 is coated with a resin 71 different from the outer resin 60 on the outer periphery of a core wire 70 formed of, for example, stainless steel. Is formed.

  The resin 71 is a material that expands in the radial direction by heat when the outer resin 60 is coated, and contracts in the radial direction after cooling, and has a higher shrinkage rate after the coating than the outer resin 60. A material having low compatibility with the outer resin 60, specifically, a fluororesin such as PTFE, ETFE, PFA, FEP, or the like is used.

  The resin 71 may not be coated on the outer periphery of all the core wires 70, and may be coated only on the outer periphery of some of the core wires 70.

  Therefore, the wire 61s has a function of expanding the diameter by heat when the outer resin 60 is coated with the resin 71 and reducing the diameter after the outer resin 60 is coated. As a result, as shown in FIG. 4, a gap K is formed between the strand 61 s and the outer resin 60, specifically, between the resin 71 and the outer resin 60.

  That is, the outer resin 60 is not bonded to the blade 61. Therefore, the strands 61 s of the blade 61 are movable in the circumferential direction and the axial direction of the strands 61 s by the gap K with respect to the skin resin 60.

  Since the outer resin 60 is bonded to the flex 62, it is prevented from being peeled off from the flexible tube portion 5.

  Next, a method for manufacturing the flexible tube portion 5 having such a configuration will be described with reference to FIGS. FIG. 5 is a partial cross-sectional view of the flexible tube portion showing a state before cooling after coating the outer periphery resin of the blade of FIG.

  First, the operator performs a blade forming process, which is a mesh tube forming process for forming the blade 61 by braiding the strands 61 s in which the resin 71 is coated on at least a part of the plurality of core wires 70.

  Next, the operator performs a blade coating process, which is a mesh tube coating process for coating the blade 61 on the outer periphery of the flex 62, and then, as shown in FIG. A skin resin coating step of coating the skin resin 60 while applying heat is performed by molding. At this time, by applying an adhesive only to the outer periphery of the flex 62, the outer resin 60 is bonded only to the outer periphery of the flex 62.

  After the coating of the outer covering resin 60, the outer covering resin 60 and the resin 71 expand in the radial direction due to heat during the covering. After that, when the skin resin 60 and the resin 71 are cooled by natural cooling or forced cooling, the resin 71 has low compatibility with the skin resin 60 and has a higher shrinkage than the skin resin 60. It hardly shrinks with respect to 60 and contracts more in the radial direction than the outer resin 60. In addition, due to the shrinkage of the outer skin resin 60, the outer skin resin 60 is fastened and fixed to the flex 62 together with the adhesive in the radial direction.

  As a result, as shown in FIG. 4, a gap K is generated between the strand 61s and the outer resin 60, and the flexible tube portion 5 is formed.

  Thus, in the present embodiment, in the flexible tube portion 5, the strand 61 s expands in the radial direction due to heat generated when the core wire 70 and the outer resin 60 are covered, and after cooling, the radial direction The outer periphery of the core wire 70 is coated with a resin 71 that is made of a material that shrinks more than the outer resin 60 and has a higher shrinkage ratio after coating than the outer resin 60 and has a low compatibility with the outer resin 60. Indicated.

  In addition, after covering with the outer resin 60, a gap K is formed between the outer resin 61 coated on the outer periphery of the core wire 70 of the element 61 s and the outer resin 60. Showed that it was movable.

  Furthermore, it has been shown that the skin resin 60 is adhered to the outer periphery of the flex 62.

  According to this, even after the covering resin 60 is coated, the strand 61s is movable with respect to the covering resin 60 by the gap K. Flexibility is not impaired.

  Further, since the outer resin 60 is fixed to the flex 62, it does not peel off.

  As described above, it is possible to provide an endoscope flexible tube 5 excellent in flexibility and elasticity without impairing durability, and a method for manufacturing the endoscope flexible tube 5.

(Second Embodiment)
FIG. 6 is a partial cross-sectional view of the flexible tube portion of the present embodiment.
The configuration of the flexible tube portion of the second embodiment is such that the blade wire itself is made of a sheath resin as compared with the flexible tube portion of the first embodiment shown in FIGS. Constructed from a material that expands in the radial direction due to heat at the time of coating, and contracts in the radial direction after cooling, and has a higher shrinkage ratio after coating than the outer resin and lower compatibility with the outer resin. Is different. Therefore, only this difference will be described, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted.

  As shown in FIG. 6, in the present embodiment, the flexible tube portion 105 includes a flex 62, a blade 161 that covers the flex 62 and is formed into a tubular shape by knitting a wire 161 s, and the blade The main part is constituted by the outer covering resin 60 covering 161.

  Each of the plurality of strands 161 s constituting the blade 161 is made of a resin 71 different from the outer skin resin 60.

  As in the first embodiment, the resin 71 is a material that expands in the radial direction due to heat when the outer resin 60 is coated and contracts in the radial direction after cooling. Further, it is made of a material having a higher shrinkage ratio after coating and lower compatibility with the outer resin 60, specifically, a fluororesin such as PTFE, ETFE, PFA, FEP, or the like.

  Further, not all of the strands 161s may be made of the resin 71, and only a part of the wire 161s may be made of the resin 71. That is, other than the strand 161s made of the resin 71, it may be made of, for example, stainless steel.

  Therefore, the wire 161s has a function of expanding the diameter by heat when the outer resin 60 is coated with the resin 71 and reducing the diameter after the outer resin 60 is coated. As a result, as shown in FIG. 6, a gap K is formed between the wire 161 s and the outer resin 60, specifically, between the resin 71 and the outer resin 60.

  That is, the outer resin 60 is not bonded to the blade 161. Therefore, the strands 161 s of the blade 161 are movable in the circumferential direction and the axial direction of the strands 161 s by the gap K with respect to the skin resin 60.

  Also in this embodiment, since the outer resin 60 is adhered to the flex 62, it is prevented from being peeled off from the flexible tube portion 5.

  Next, a method for manufacturing the flexible tube portion 5 having such a configuration will be described with reference to FIGS. FIG. 7 is a partial cross-sectional view of the flexible tube portion showing a state before cooling after coating the outer periphery resin on the outer periphery of the blade of the present embodiment.

  First, the operator braids the strand 161s made of the resin 71, and performs a blade forming process, which is a mesh tube forming process for forming the blade 161.

  Next, the worker performs a blade coating process, which is a mesh tube coating process for coating the blade 161 on the outer periphery of the flex 62, and then, as shown in FIG. A skin resin coating step of coating the skin resin 60 while applying heat is performed by molding. At this time, by applying an adhesive only to the outer periphery of the flex 62, the outer resin 60 is bonded only to the outer periphery of the flex 62.

  After the coating of the outer covering resin 60, the outer covering resin 60 and the resin 71 expand in the radial direction due to heat during the covering. After that, when the skin resin 60 and the resin 71 are cooled by natural cooling or forced cooling, the resin 71 has low compatibility with the skin resin 60 and has a higher shrinkage than the skin resin 60. It hardly shrinks with respect to 60 and contracts more in the radial direction than the outer resin 60. In addition, due to the shrinkage of the outer skin resin 60, the outer skin resin 60 is fastened and fixed to the flex 62 together with the adhesive in the radial direction.

  As a result, as shown in FIG. 6, a gap K is generated between the strand 161s and the outer skin resin 60, and the flexible tube portion 105 is formed.

  As described above, in the present embodiment, in the flexible tube portion 105, the wire 161s expands in the radial direction due to heat generated when the outer resin 60 is coated, and contracts in the radial direction after cooling. A material having a higher shrinkage ratio after coating than the outer resin 60 and having a low compatibility with the outer resin 60, specifically, a resin composed of a fluororesin such as PTFE, ETFE, PFA, FEP, etc. 71.

  Further, it is shown that a gap K is formed between the strand 161s and the sheath resin 60 after the coating of the sheath resin 60, and the strand 161s is movable with respect to the sheath resin 60 by the gap K.

  According to this, even after the covering resin 60 is coated, the strand 161s is movable with respect to the covering resin 60 by the gap K. Flexibility is not impaired.

  Therefore, the same effect as that of the first embodiment can be obtained. Other effects are the same as those of the first embodiment described above.

(Third embodiment)
FIG. 8 is a partial cross-sectional view of the flexible tube portion of the present embodiment.
The configuration of the flexible tube portion of the third embodiment is coated on the outer periphery of the blade strand as compared with the flexible tube portion of the first embodiment shown in FIGS. 1 to 5 described above. The difference is that a coating with a lower friction coefficient is applied to the outer periphery of the resin. Therefore, only this difference will be described, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted.

  As shown in FIG. 8, in the present embodiment, the flexible tube portion 205 includes a flex 62 and a blade formed into a tubular shape by knitting a strand 261 s covering the flex 62 from the inner peripheral surface side. 261 and the outer resin 60 that covers the blade 261 constitute a main part.

  Each of the plurality of strands 261s constituting the blade 261 is coated with a resin 71 different from the outer resin 60 on the outer periphery of the core wire 70 formed of, for example, stainless steel. It is formed by applying a coating 76 having a low coefficient, for example, DLC or paraxylylene.

  The resin 71 is a material that expands in the radial direction due to heat when the outer shell resin 60 is coated as in the first embodiment, and contracts in the radial direction after cooling. Is also made of a material having a large shrinkage ratio after coating.

  In addition, the resin 71 and the coating 76 may not be coated on the outer periphery of all the core wires 70, and may be coated only on the outer periphery of a part of the core wires 70.

  Therefore, the strand 261s has a function of expanding the diameter by heat when the outer resin 60 is coated with the resin 71 and reducing the diameter after the outer resin 60 is coated. As a result, as shown in FIG. 8, a gap K is formed between the wire 261 s and the outer resin 60, specifically, between the coating 76 and the outer resin 60.

  That is, the outer resin 60 is not bonded to the blade 261. Therefore, each strand 261 s of the blade 261 is movable in the circumferential direction of each strand 261 s with respect to the outer resin 60 by the gap K.

  Also in this embodiment, since the outer resin 60 is adhered to the flex 62, it is prevented from being peeled off from the flexible tube portion 5.

  Next, a method for manufacturing the flexible tube portion 205 having such a configuration will be described with reference to FIGS. FIG. 9 is a partial cross-sectional view of the flexible tube portion showing a state before cooling after coating the outer periphery resin of the blade of the present embodiment with the outer resin and coating the outer resin.

  First, the operator is a mesh tube forming process in which the resin 71 is coated on at least a part of the plurality of core wires 70, and the strands 261 s coated with the coating 76 are braided to form the blade 261. A blade forming process is performed.

  Next, the worker performs a blade coating process, which is a mesh tube coating process for coating the blade 261 on the outer periphery of the flex 62, and then, as shown in FIG. A skin resin coating step of coating the skin resin 60 while applying heat is performed by molding. At this time, by applying an adhesive only to the outer periphery of the flex 62, the outer resin 60 is bonded only to the outer periphery of the flex 62.

  After the coating of the outer covering resin 60, the outer covering resin 60 and the resin 71 expand in the radial direction due to heat during the covering. After that, when the skin resin 60 and the resin 71 are cooled by natural cooling or forced cooling, the resin 71 has low compatibility with the skin resin 60 and has a higher shrinkage than the skin resin 60. It hardly shrinks with respect to 60 and contracts more in the radial direction than the outer resin 60. In addition, due to the shrinkage of the outer skin resin 60, the outer skin resin 60 is fastened and fixed to the flex 62 together with the adhesive in the radial direction.

  As a result, as shown in FIG. 6, a gap K is generated between the wire 261 s and the outer resin 60, and the flexible tube portion 5 is formed.

  As described above, in the present embodiment, the strand 261s of the blade 261 is configured by coating the outer periphery of the core wire 70 with the resin 71 and further applying the coating 76 with a low friction coefficient on the outer periphery of the resin 71. It has been shown.

  According to this, in addition to the effect of the first embodiment described above, the wire 261s is more slippery with respect to the outer resin 60 due to the coating 76, and therefore, the electric wire 261s with respect to the outer resin 60 becomes more sensible. Makes it easier to move. Other effects are the same as those of the first embodiment described above.

5. Flexible tube (flexible tube for endoscope)
60 ... Outer resin 61 ... Blade (Reticulated tube)
61s ... Wire 62 ... Flex (core material)
71 ... Resin different from outer resin 105 ... Flexible tube (flexible tube for endoscope)
161 ... Blade (mesh tube)
161s ... strand 205 ... flexible tube (flexible tube for endoscope)
261 ... Blade (mesh tube)
261s ... strand K ... gap

Claims (10)

A flexible tube for an endoscope, comprising: a mesh tube formed by braiding a plurality of strands; and a sheath resin coated on the mesh tube,
A gap is formed between the element wire and the outer resin, and the element wire is positioned so as to be movable with respect to the outer resin by the gap . Flexible tube. The mesh tube is coated on the core material,
The flexible tube for an endoscope according to claim 1, wherein the outer resin is fixed to the core member. The wire is expanded by heat when the outer resin is coated and reduced in diameter after the outer resin is coated,
The flexible tube for an endoscope according to claim 1 , wherein the gap is formed between the strand after diameter reduction and the outer resin. At least a part of the strand is coated with a resin different from the outer resin,
The resin different from the outer resin is composed of a material that expands in the radial direction due to heat when the outer resin is coated on the element wire and contracts in the radial direction when cooled. The flexible tube for an endoscope according to claim 3.   The flexible tube for an endoscope according to claim 4, wherein the resin coated on at least a part of the strand is made of a material having low compatibility with the outer resin. At least a part of the strand is made of a resin different from the outer resin,
The resin different from the outer resin is composed of a material that expands in the radial direction due to heat when the outer resin is coated on the element wire and contracts in the radial direction when cooled. The flexible tube for an endoscope according to claim 3.   The flexible tube for an endoscope according to claim 6, wherein a resin constituting at least a part of the strand is made of a material having low compatibility with the outer resin. A mesh tube forming step of braiding a plurality of strands to form a mesh tube;
After the mesh tube forming step, a mesh tube coating step for coating the mesh tube on the core material;
A sheath resin coating step of coating the sheath resin while applying heat to the mesh tube so that the mesh tube is movable with respect to the sheath resin;
Equipped with,
The method for manufacturing a flexible tube for an endoscope , wherein, in the outer resin coating step, the outer resin is fixed only to the core material . The mesh tube forming step is different from the outer resin and compatible with the outer resin that expands in the radial direction by heat when the outer resin is coated on the strands and contracts in the radial direction when cooled. Low resin is performed by braiding a plurality of strands coated at least in part,
After the outer sheath resin coating step, by different resin shrinks in the radial direction and the outer sheath resin, between the outer sheath resin and the wire, according to claim 8, characterized in that a gap is formed Manufacturing method for flexible tube for endoscope. The mesh tube forming step is different from the outer resin and compatible with the outer resin that expands in the radial direction by heat when the outer resin is coated on the strands and contracts in the radial direction when cooled. Is performed by braiding a plurality of strands at least partly composed of a low resin,
After the outer sheath resin coating step, by different resin shrinks in the radial direction and the outer sheath resin, between the outer sheath resin and the wire, according to claim 8, characterized in that a gap is formed Manufacturing method for flexible tube for endoscope.

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