JP2007252560A - Insertion portion for endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an insertion portion for endoscopes for smoothly coupling an insertion portion flexible tube and a bending portion without making a length of a rigid part of a connecting part between the insertion portion flexible tube and the bending portion long and having a thin part locally in a flexible outer sheath formed by extrusion molding in the insertion portion for endoscopes which uses flexible tube frame bodies formed by rotatably coupling a plurality of short cylindrical joint rings, instead of a helical tube, by a coupling axis and has the flexible outer sheath formed by extrusion molding. <P>SOLUTION: Inner and outer diameters of a front half portion 12Aa of the joint ring 12A at the furthermost distal end of the flexible tube frame bodies 12, 13 constituting the insertion portion flexible tube 10 are made larger than the inner and outer diameters of a rear half portion 12Ab. A reticulated tube 14 is fixed on the peripheral surface of the rear half portion 12Ab, and the outer periphery of the reticulated tube 14 is coated with the flexible outer sheath 15. A connection cap 21 at the proximal end of the bending portion 2 is inserted in the inner peripheral side of the front half portion 12Aa to connect them. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an insertion portion of an endoscope.

The insertion tube of an endoscope generally has a flexible tube frame made of a metal spiral tube covered with a mesh tube braided with fine metal wires, and a flexible sheath is extruded on the outer periphery. Although it is configured to be covered by molding, shrinkage may occur in the metal spiral tube when high-temperature and high-pressure steam sterilization (autoclave) is performed after using the endoscope. Therefore, in order to obtain durability against the autoclave, it is preferable to use a flexible tubular frame structure in which a plurality of short cylindrical joint rings are rotatably connected by a connecting shaft instead of a helical tube (for example, Patent Document 1). .
JP-A-9-24020

  In an endoscope insertion portion, generally, a bending portion that can be bent at an arbitrary angle in an arbitrary direction by a remote operation is connected to the distal end of the insertion portion flexible tube, and is described in FIG. In the invention, the front half of the joint ring at the tip of the insertion portion flexible tube is inserted into and connected to the connection base provided at the rear end of the curved portion, and the mesh tube is applied to the rear end surface of the connection base. In this state, it is fixed to the outer peripheral surface of the rear half of the most advanced joint ring by soldering or the like, and the outer periphery thereof is covered with a flexible outer skin.

  In the manufacturing process of the insertion part of the endoscope having such a configuration, the step of soldering the tip of the mesh tube to the outer peripheral surface of the rear half of the most advanced joint ring is performed before the flexible skin is coated. Therefore, it is performed before the connection with the connection base at the rear end of the curved portion, which is performed after the covering of the flexible outer skin.

  Therefore, the soldering operation to fix the tip of the mesh tube to the rear half of the most advanced joint ring must be done carefully so that the solder does not flow out to the front half of the most advanced joint ring. There is.

  When solder (or a reticulated tube that has been hardened with solder) hits the front half of the most advanced joint ring and the outer diameter of the front half of the most advanced joint ring increases, This is because the front half of the joint ring cannot be inserted into the connection base at the rear end of the curved portion.

  However, when soldering the rear half of the outer peripheral surface of the most advanced joint ring, it is not easy to work so that the solder does not flow to the front half. On the contrary, it flows out between the meshes of the rear mesh tube, the length of the hard part of the connecting part of the insertion part flexible tube and the bending part becomes long, and only that part is difficult to bend in the body when using the endoscope, and the insertion performance May fall.

  However, like the insertion part of the conventional endoscope illustrated in FIG. 6, when the structure in which the distal end portion of the mesh tube 92 is inserted into the inner peripheral side of the distal end cap 91 of the insertion part flexible tube is adopted. Since the outer diameter of the tip cap 91 becomes large at the portion A, when the flexible outer skin 93 is extruded, the thickness of the flexible outer skin 93 is locally reduced only in that portion A for manufacturing and durability. A big problem arises.

  Accordingly, the present invention provides an endoscope in which a flexible tube frame is used in which a plurality of short cylindrical joint rings are rotatably connected by a connecting shaft instead of a spiral tube, and a flexible skin is formed by extrusion molding. In the insertion portion of the insertion portion, there is no occurrence of a thin portion locally in the flexible outer shell formed by extrusion molding or the length of the hard portion of the connection portion between the insertion portion flexible tube and the bending portion is increased. An object of the present invention is to provide an insertion portion of an endoscope that can smoothly connect a flexible tube and a bending portion.

  In order to achieve the above object, the insertion portion of the endoscope of the present invention has an outer periphery of a flexible tube frame in which a plurality of insertion portion flexible tubes are connected to a plurality of short cylindrical joint rings by a connecting shaft. In addition, it is constructed by covering a mesh tube braided with fine metal wires and covering the outer periphery with a flexible outer shell by extrusion molding, and inserting it into a connection base provided at the rear end of a curved portion bent by remote operation The inner and outer diameters of the front half of the most advanced joint ring are the inner and outer diameters of the rear half of the endoscope joint in which the most advanced joint rings of the plurality of flexible tubes are connected and connected. It is formed to a larger diameter, a mesh tube is fixed to the outer peripheral surface of the rear half, and the outer periphery thereof is covered with a flexible outer shell, and the connection base at the rear end of the curved portion is provided on the inner peripheral side of the front half. It is connected and connected.

  In addition, the outer peripheral surface of the rear half of the joint ring is preferably formed in a circular shape with no change in diameter, and the mesh tube is fixed to the outer peripheral surface of the rear half of the most advanced joint ring by soldering. May be.

  According to the present invention, the inner and outer diameters of the front half of the most advanced joint ring are formed to be larger than the inner and outer diameters of the rear half, and the reticulated pipe is fixed to the outer peripheral surface of the rear half. By covering the outer periphery with a flexible outer shell and inserting and connecting the connecting base at the rear end of the curved portion to the inner peripheral side of the front half, the short cylindrical joint ring is replaced with a connecting shaft instead of the helical tube. In the insertion part of an endoscope in which a flexible tube frame that is pivotally connected and a flexible outer skin is formed by extrusion molding, the length of the hard part of the connection part between the insertion part flexible tube and the bending part The insertion portion flexible tube and the bending portion can be smoothly connected without causing a thin portion to be locally generated in the flexible outer shell formed by extrusion or extrusion molding.

  The insertion section flexible tube covers the outer periphery of a flexible tube frame in which a plurality of short cylindrical joint rings are rotatably connected by a connecting shaft, and the outer periphery of the flexible tube is covered with a mesh tube braided with fine metal wires. The most advanced joint ring in the multiple joint rings of the insertion part flexible tube is connected to the connection base provided at the rear end of the curved part that is formed by covering the flexible skin by extrusion molding and bending by remote control In the insertion part of the endoscope, the inner and outer diameters of the front half of the most advanced joint ring are formed larger than the inner and outer diameters of the rear half, and a mesh tube is fixed to the outer peripheral surface of the rear half Further, the outer periphery is covered with a flexible outer skin, and the connection base at the rear end of the curved portion is inserted and connected to the inner peripheral side of the front half, and the outer peripheral surface of the rear half of the joint ring Is formed in the shape of a circumferential surface having no diameter change.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 2 shows the overall configuration of the endoscope. The bending portion 2 that can be bent by remote operation is connected to the distal end of the insertion portion flexible tube 10 to be inserted into the body, and an observation window and the like are arranged. The distal end body 3 is connected to the distal end of the bending portion 2. Reference numeral 5 denotes an operation unit in which an operation knob 6 and the like for performing a bending operation and the like of the bending unit 2 are arranged.

  FIG. 3 shows an insertion portion flexible tube 10. In this embodiment, the insertion portion flexible tube 10 has a short cylindrical joint ring 12 that can be rotated by a connecting shaft 13 formed in a rivet shape, for example. A plurality of (for example, several tens to several hundreds) connected flexible bendable flexible tube frames are formed, and a mesh tube 14 formed by braiding metal thin wires is formed on the outer periphery of the flexible tube frame. Further, the outer periphery is covered with a flexible outer skin 15 by extrusion molding.

  A rear end cap 16 is provided at the rear end portion of the insertion portion flexible tube 10 so as to be connected to the operation portion 5. Note that various built-in objects such as an optical fiber bundle and a flexible tube are inserted and arranged in the insertion portion flexible tube 10, but the illustration thereof is omitted in each drawing.

  For example, as shown in FIG. 4, each joint ring 12 formed in a short cylindrical shape has a pair of tongue pieces 121 protruding at a 180 ° symmetrical position on one end side, and 90 ° with one end side on the other end side. A pair of tongue pieces 122 are formed to project at 180 ° symmetrical positions in different directions.

  Then, when the plurality of joint rings 12 are arranged with their axes aligned, the one tongue piece 121 is brought inward by the thickness thereof so that the tongue pieces 121 and 122 of the adjacent joint rings 12 overlap each other. The tongues 121 and 122 are formed with holes 123 and 124 through which the connecting shaft 13 is passed.

  Accordingly, each joint ring 12 is connected to the adjacent joint ring 12 by the connecting shaft 13 at a 180 ° symmetrical position on one end side, and at a 180 ° symmetrical position in a direction changed from the one end side by 90 ° on the other end side. The adjacent joint ring 12 is connected to the connecting shaft 13. Note that the difference in direction between the one end side and the other end side may be other than 90 ° (for example, 45 ° or 60 °).

  However, since only the most advanced joint ring 12A needs to be connected / coupled to the bending portion 2 side, the configuration is different from the other joint rings 12, and the shape thereof is shown as a single unit in FIG. A cross section is shown in FIG.

  The state-of-the-art joint ring 12A is formed in a stepped cylindrical shape in which the inner diameter and outer diameter of the front half 12Aa are larger than the inner diameter and outer diameter of the rear half 12Ab. In this case, the “half part” of the front half part 12Aa and the rear half part 12Ab does not mean a part that is about half the length, This means that it is distinguished from “a portion with a small diameter”.

  At the rear end of the rear half 12Ab of such a state-of-the-art joint ring 12A (the right side in FIG. 5 and the upper side in FIG. 1), as shown in FIG. The tongue piece 122 is formed so as to protrude, and a hole 124 for passing the connecting shaft 13 is formed therethrough. The front half 12Aa is connected to the connection base 21 provided at the rear end of the bending portion 2. A countersunk hole 120 through which the screw 17 for connecting and fixing is passed is formed.

  As shown in FIG. 1, in the manufacturing process, before the flexible skin 15 is covered, the distal end portion of the mesh tube 14 is formed on the outer peripheral surface of the rear half 12 </ b> Ab of the most advanced joint ring 12 </ b> A. It is covered and fixed by soldering, and the outer periphery is covered with a flexible outer skin 15 by extrusion molding. In the manufacturing process, the connection cap 21 of the bending portion 2 is not connected and connected at that time.

  The connection base 21 at the rear end of the bending portion 2 is inserted into the inner peripheral part of the front half 12Aa of the most advanced joint ring 12A, and the screw 17 formed in the connection base 21 through the countersunk hole 120 is formed. The state-of-the-art joint ring 12 </ b> A and the connection base 21 are connected to each other by being tightened in the hole.

  In such a process, the outer diameter of the rear half 12Ab of the most advanced joint ring 12A where the mesh tube 14 is soldered is smaller than the outer diameter of the front half 12Aa, and the rear half 12Ab Since there is a step at the boundary with the side half 12Aa, it is unlikely that soldering will flow from the rear half 12Ab to the front half 12Aa.

  Further, since the connection base 21 is connected and connected in a state of being inserted into the inner peripheral side of the front half 12Aa of the most advanced joint ring 12A, the solder is temporarily connected from the rear half 12Ab side to the front half 12Aa. Even if it flows out to the outer surface on the side, there will be no trouble in connection and connection with the connection base 21.

  Therefore, the soldering operation of the mesh tube 14 can be performed with the attention force directed to the solder so that the solder does not flow out to the mesh of the rear mesh tube 14, and the connection between the insertion portion flexible tube 10 and the bending portion 2 can be performed. An excellent insertability can be obtained by preventing the hard length of the portion from becoming long.

  Further, since the outer peripheral surface of the rear half 12Ab of the most advanced joint ring 12A is formed in the shape of a circumferential surface that does not change in diameter, the flexible outer skin 15 covered by the mesh tube 14 covered therewith. The thickness of the film becomes constant, and there is no problem in manufacturing and durability.

  The distal end portion of the flexible outer skin 15 is overlapped with the rear end portion of the elastic outer skin 22 of the bending portion 2 on the outer periphery thereof, and is fastened and fixed by a binding thread 18, and an adhesive 19 is further applied to the periphery thereof. Reference numeral 23 denotes a guide coil for guiding the bending operation wire 24 in the insertion portion flexible tube 10, and the most distal end portion thereof is fixed to the inner peripheral surface of the connection base 21 by brazing or the like.

  The present invention is not limited to the above-described embodiment. For example, the mesh tube 14 may be fixed to the state-of-the-art joint ring 12A by brazing or adhesive other than soldering. .

It is side surface sectional drawing of the connection connection part of the insertion part flexible tube and bending part of the endoscope of the Example of this invention. 1 is a side view showing an overall configuration of an endoscope according to an embodiment of the present invention. It is side surface sectional drawing of the insertion part flexible tube of the endoscope of the Example of this invention. FIG. 3 is a perspective view of a single joint ring used in the insertion tube flexible tube of the endoscope according to the embodiment of the present invention. It is a perspective view of the single-piece | unit of the most advanced joint ring used for the insertion part flexible tube of the endoscope of the Example of this invention. It is side surface sectional drawing of the connection connection part of the insertion part flexible tube and bending part of the conventional endoscope.

Explanation of symbols

2 bending portion 10 insertion portion flexible tube 12 articulated ring (flexible tube frame)
12A State-of-the-art joint ring 12Aa Front half 12Ab Rear half 13 Connecting shaft (flexible tube frame)
14 Reticulated tube 15 Flexible outer skin 21 Connection base

Claims (3)

The insertion section flexible tube covers the outer periphery of a flexible tube frame in which a plurality of short cylindrical joint rings are rotatably connected by a connecting shaft, and the outer periphery of the flexible tube is covered with a mesh tube braided with fine metal wires. The most advanced joint ring in the plurality of joint rings of the insertion section flexible tube is connected to the connection base provided at the rear end of the curved section that is configured by covering the flexible outer skin by extrusion molding and bending by remote control In the insertion part of the connected endoscope,
The inner and outer diameters of the front half of the state-of-the-art joint ring are formed to be larger than the inner and outer diameters of the rear half, and the mesh tube is fixed to the outer peripheral surface of the rear half, and further the An insertion portion of an endoscope, which covers a flexible outer skin and is connected and connected by inserting a connection base at the rear end of the bending portion on the inner peripheral side of the front half.   The endoscope insertion portion according to claim 1, wherein an outer peripheral surface of a rear half portion of the joint ring is formed in a circumferential surface shape having no diameter change.   The insertion portion of the endoscope according to claim 1 or 2, wherein the mesh tube is fixed to an outer peripheral surface of a rear half portion of the most advanced joint ring by soldering.

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