JP2011189089A - Endoscope flexible tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope flexible tube having such a constitution that an outer sheath is attached to an outer circumferential surface of a net-like tube formed by braiding a plurality of wire bundles in which metallic wires and nonmetallic wires are juxtaposed, the endoscope flexible tube having excellent durability hardly generating wrinkles and buckling after repeated use. <P>SOLUTION: The net-like tube 12 is formed by braiding the plurality of wire bundles 22. In each of the wire bundles 22, development lengths of non-metallic fiber wires 22b are formed longer than those of metallic wires 22a, consequently the non-metallic fiber wires 22b are in a loosened state with respect to the metallic wires 22a as a whole. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a flexible tube of an endoscope.

  A flexible tube of an endoscope is generally a flexible synthetic resin sheath, in which a mesh tube formed by braiding a plurality of strands in which a plurality of thin wires are juxtaposed is coated on the outer periphery of a spiral tube. Has a configuration in which the outer periphery of the mesh tube is covered by extrusion or the like.

  In such a flexible tube of an endoscope, if the outer skin is peeled off from the mesh tube by bending it with a small radius of curvature, it may become unusable due to wrinkles and buckling. Not a few. Therefore, there are many cases in which the outer skin is bonded and fixed to the mesh tube.

  However, if the outer skin is adhered and fixed to the reticulated tube, the flexibility of the flexible tube is too low (that is, it becomes too hard), and the tube cannot be bent into a hollow organ such as the large intestine. Insertability may deteriorate.

  Therefore, as illustrated in FIG. 6, the metal wire 51 a and the non-metallic fiber wire 51 b are juxtaposed in the strand bundle 51 constituting the mesh tube 50 so that preferable flexibility can be obtained. There is (for example, Patent Document 1).

JP 59-36

  The flexible tube of the endoscope is repeatedly bent irregularly with a small radius of curvature during use (ie, during endoscopy). Then, each time the mesh of the mesh tube is deformed to be expanded or narrowed, the wire forming the strand of the mesh tube is strongly pulled or loosened in various directions.

  Then, the non-metallic fiber wire, which is weaker than the metal wire and has a low shape restoring property, moves to the operation of loosening after being pulled strongly and stretched, so that the arrangement in the wire bundle is compared to the original state May be disturbed.

  7 and 8 are partial cross-sectional views of the flexible tube illustrating the state change of the mesh tube 50 as described above. 40 is a spiral tube, and 60 is an outer skin. The non-metallic fiber wire 51b that forms the strand bundle 51 with the plurality of metal wires 51a initially forms the strand bundle 51 in an orderly manner with the metal wires 51a as shown in FIG.

  However, as shown in FIG. 8, when the arrangement of the non-metallic fiber wires 51b is disturbed compared to the initial state, the outer skin 60 is likely to be deformed at the portion bonded to the non-metallic fiber wires 51b. It becomes a source of crunch and buckling.

  The present invention is an endoscope flexible tube having a structure in which an outer skin is bonded to an outer peripheral surface of a mesh tube formed by braiding a plurality of strands of wire in which metal wires and non-metal fiber wires are juxtaposed. An object of the present invention is to provide a flexible tube for an endoscope that is less likely to cause wrinkles and buckling after repeated use and has excellent durability.

  In order to achieve the above object, the flexible tube of the endoscope of the present invention is formed by braiding a plurality of strands in which at least one metal wire and at least one non-metallic fiber wire are juxtaposed. An endoscope flexible tube having a configuration in which a mesh tube is coated on the outer periphery of a spiral tube, and a flexible synthetic resin sheath is coated and adhered to the outer surface of the mesh tube. In the wire bundle, the unfolded length of the non-metallic fiber wire is formed longer than the unfolded length of the metal wire, and a net-like tube is formed by braiding a plurality of strands in which the non-metallic fiber wire is loosened relative to the metal wire as a whole. It is what.

  In addition, each non-metallic fiber wire may be in the state loosened partially with respect to the metal wire juxtaposed with it.

  According to the present invention, in each strand bundle constituting the reticular tube, the unfolded length of the nonmetallic fiber wire is formed longer than the unfolded length of the metal wire, and the nonmetallic fiber wire is loosened relative to the metal wire as a whole. Since the mesh tube is formed by braiding a plurality of wire bundles, the arrangement of the non-metallic fiber wires is less disturbed than the original state even when repeatedly bent irregularly with a small radius of curvature during use. It is difficult to generate wrinkles and buckling, and excellent durability can be obtained.

It is the elements on larger scale of the state which looked from the outer surface side in the state which developed the reticular tube of the flexible tube of the endoscope concerning the example of the present invention. It is a partial expanded side sectional view of the flexible tube of the endoscope concerning the example of the present invention. 1 is an external view showing an overall configuration of an endoscope according to an embodiment of the present invention. It is a side surface fragmentary sectional view of the flexible tube of the endoscope which concerns on the Example of this invention. It is side surface sectional drawing which shows an example of the manufacturing process of the mesh tube of the flexible tube of the endoscope which concerns on the Example of this invention. It is the elements on larger scale of the state which looked from the outer surface side in the state which developed the mesh tube of the flexible tube of the conventional endoscope. It is a partial expanded side sectional view of the flexible tube of the conventional endoscope. It is a partial expanded side sectional view of the state after repeated use in the flexible tube of the conventional endoscope.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 3 shows the overall configuration of the endoscope according to the embodiment of the present invention. A bending operation knob 3 provided in the operation unit 2 is provided at the distal end portion of the flexible tube 1 connected to the operation unit 2. A bending portion 4 that can be bent in an arbitrary direction by an arbitrary angle by rotating operation is connected.

  Further, a distal end body 5 incorporating an objective optical system, a solid-state imaging device and the like is connected to the distal end side of the bending portion 4. A connector (not shown) connected to a video processor that is an external device is attached to the end of the flexible connection cord 6 that extends from the operation unit 2.

  FIG. 4 shows the structure of the intermediate portion of the flexible tube 1 with the cross-sectional position being changed sequentially from the tip side. Note that various built-in objects such as signal cables, optical fiber bundles, tubes, and the like are inserted into the flexible tube 1, but the illustration thereof is omitted.

  The basic configuration of the flexible tube 1 is the same as the flexible tube of a general endoscope, and a mesh tube 12 is provided on the outer periphery of a double spiral tube 11 made of a metal strip having a different winding direction. A sheath 13 made of synthetic resin having flexibility is coated on the outer periphery of the mesh tube 12. The spiral tube 11 may be single or triple.

  The reticulated tube 12 is basically formed by braiding a plurality of strands 22 in which a plurality of thin wires are juxtaposed, as is well known. FIG. 2 shows an enlarged cross-sectional structure of the flexible tube 1, and FIG. 1 shows an enlarged view of only the mesh tube 12 of the flexible tube 1 as viewed from the outer surface side. ing.

  The strand bundle 22 constituting the mesh tube 12 is formed by juxtaposing a plurality of metal wires 22a and a plurality of non-metal fiber wires 22b. However, it is sufficient that at least one metal wire 22a and at least one non-metallic fiber wire 22b are juxtaposed. By selecting the number of the non-metallic fiber wires 22b, it is possible to obtain flexibility that is preferable as the flexible tube 1, and it is also possible to obtain soft flexibility suitable for insertion into the large intestine or the like.

  Each wire 22a, 22b has a diameter of, for example, about 0.1 mm, and a wire bundle 22 is formed by juxtaposing about 5 to 15 wires including the metal wire 22a and the non-metallic fiber wire 22b. For example, about 24 to 48 wire bundles 22 are braided to form one reticulated tube 12.

  The outer skin 13 is made of, for example, a flexible thermoplastic polyurethane resin, and is extruded on the outer peripheral surface of a material tube (that is, a tubular body in which the outer peripheral surface of the spiral tube 11 is covered with the mesh tube 12). Etc., and is coated and bonded to the entire outer periphery of the mesh tube 12. As the adhesive, a silicone-based or urethane-based adhesive that does not become hard even when cured is suitable.

  A stainless steel wire or the like is used as the metal wire 22a constituting each strand 22 and a non-metal fiber wire 22b is a material that has excellent chemical resistance and does not melt by heat in the process of covering the outer skin 13 ( For example, an aramid fiber is preferable.

  In each such strand bundle 22, the unfolded length of the non-metallic fiber wire 22b is formed longer than the unfolded length of the metal wire 22a, and a plurality of strand bundles with the non-metallic fiber wire 22b loosened relative to the metal wire 22a as a whole. 22 is braided to form a mesh tube 12.

  As a result, each non-metallic fiber wire 22b may be partially loosened as illustrated in FIG. 1 with respect to the metal wire 22a juxtaposed with the non-metallic fiber wire 22b. As shown in FIG. 2, the outer skin 13 is coated.

  Even when the flexible tube 1 having such a configuration is repeatedly and irregularly bent with a small radius of curvature while being used for endoscopy or the like, the non-metallic fiber wire 22b may be pulled strongly. It is hard to be in a state where it is fully extended.

  Therefore, even if it moves to the operation | movement which next loosens the nonmetallic fiber wire 22b, it is a thing which was in the loosened state originally, Therefore Compared with the original state, the arrangement | sequence of the nonmetallic fiber wire 22b is hard to be disturbed. As a result, the cross-sectional shape of the outer skin 13 is not easily deformed, and even when the flexible tube 1 is repeatedly bent irregularly with a small curvature radius, wrinkles and buckling are unlikely to occur.

  In order to form the unfolded length of the nonmetallic fiber wire 22b longer than the unfolded length of the metal wire 22a in the mesh tube 12 formed by the strand bundle 22 in which the metal wire 22a and the nonmetallic fiber wire 22b are juxtaposed, for example In the step before the outer skin 13 is coated by extrusion molding or the like, a method of squeezing the surface of the mesh tube 12 with the elastic ring 30 or the like can be used as schematically shown in FIG.

  In the state shown in FIG. 5, the mesh tube 12 is covered with the spiral tube 11, and a flexible core material is placed in the spiral tube 11 so that the spiral tube 11 can maintain a stable shape. Has been passed.

  Before the mesh tube 12 is covered with the spiral tube 11, the mesh tube 12 is left in a state of being bent to a predetermined curvature radius (for example, about the allowable minimum curvature radius of the flexible tube 1), and the metal wire 22 a of each strand bundle 22 is left. And the non-metallic fiber wire 22b are in a state of being bent.

  The elastic ring 30 is an annular member made of an elastic rubber material or the like, and is attached to the inside of a holding ring 31 made of a rigid body. The inner diameter size of the elastic ring 30 is slightly smaller than the outer diameter size of the mesh tube 12.

  Therefore, as shown in FIG. 5, when the elastic ring 30 that is engaged with the outer surface of the mesh tube 12 and is elastically expanded is slid in the axial direction, the outer surface of the mesh tube 12 becomes elastic ring. The non-metallic fiber wire 22b, which is squeezed at 30 and has poor straightness, is partially removed from the gap between the metal wires 22a and extended.

  In addition, when it is necessary to further improve the durability against wrinkles and buckling, when the outer skin 13 is extruded, the melted outer shell resin is formed between the mesh portion of the mesh tube 12 and the gap between the spiral tubes 11. You may make it protrude to the side etc. Further, even when a method other than extrusion molding is employed as a method of covering the outer skin 13 on the outer periphery of the mesh tube 12, it is included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Flexible tube 11 Spiral tube 12 Reticulated tube 13 Outer skin 22 Strand bundle 22a Metal wire 22b Non-metallic fiber wire

Claims (2)

A mesh-like tube formed by braiding a plurality of strands in which at least one metal wire and at least one non-metallic fiber wire are juxtaposed is covered on the outer periphery of the spiral tube, and is made of a flexible synthetic resin. A flexible tube of an endoscope having a configuration in which the outer skin is coated and bonded to the outer peripheral surface of the mesh tube,
In each of the above-mentioned strand bundles, the unfolded length of the non-metallic fiber wire is formed longer than the unfolded length of the metal wire, and as a whole, a plurality of strand bundles in which the non-metallic fiber wire is loosened with respect to the metal wire are braided A flexible tube for an endoscope, wherein the mesh tube is formed.   The flexible tube for an endoscope according to claim 1, wherein each of the non-metallic fiber wires is partially slackened with respect to the metal wires juxtaposed with the non-metallic fiber wires.

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