JPS6330404Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to the internal structure of a flexible and curved tube of an endoscope insertion section, and is particularly concerned with preventing the optical fiber bundle from being compressed by other internal objects built into the flexible tube. The present invention provides an effective means for preventing the optical fiber bundle from being caught and being pressed by the protrusion of the guide portion that guides the bending operation wire as it approaches the tip bendable portion.

When inserting a medical endoscope into a body cavity, it is important to reduce the outer diameter of the flexible and curved tube at the insertion part, even by 0.1 mm, to reduce patient pain. Flexible curved tubes are required to be extremely thin. Therefore, it is necessary to make the outer sheath of the optical fiber bundle housed in the flexible and curved tube as thin as possible, so the outer sheath is made of a thin silicon tube or a thin wall plastic tube with a wall thickness of about 0.1 to 0.2 mm. However, in order to observe the inner wall of the body cavity without blind spots,
In response to usage demands for increasing the curvature angle of the tip to, for example, 180° in each vertical direction, conventional methods for wrapping optical fiber bundles lacked durability.

Inside the flexible tube of the endoscope, in addition to the optical fiber bundles for the image guide and light guide, there are channels for forceps insertion, air and water tubes, wires for bending the tip, etc. As mentioned above, the outer diameter of the flexible and curved tube is kept to an extremely small size in order to reduce patient pain, so each built-in component is built in a dense state, so the tip can be curved. Each time the flexible tube is moved, internal components such as optical fiber bundles rub or press against each other within the flexible tube. As shown in Figure 2, the structure of a normal curved part uses a connecting ring 5 connected in the diametrical direction with rivets 6, etc., and its neutral axis is located at the center of the axis of the curved part with respect to the curved surface. Therefore, when a bending operation is performed, the built-in objects located on the inner diameter side of the curve become shorter and are compressed or moved in the direction of being pushed out toward the operating section, and the built-in objects located on the outer diameter side become shorter. This is because each built-in component moves in the same direction or in opposite directions with respect to the axial direction, causing friction as it is pulled and pushed toward the inner diameter side or moved in the direction of being drawn into the flexible tube from the operating section side. , optical fiber bundles sheathed in conventional thin-walled tubes are compressed and tensioned. In addition, an exterior made of a thin-walled tube such as a silicone tube is weak and may be compressed and crushed during the above-mentioned bending operation, or the flexible tube may not have the force to push toward the operating section, resulting in buckling and bending at the tip. Alternatively, the optical fiber bundle may be bent and damaged due to meandering within the flexible tube. Furthermore, when the curved portion of a hard plastic tube 9 such as a forceps channel is bent, it tends to become as straight as possible within the curved portion, as shown in Fig. 3, so each optical fiber bundle 7 is inevitably pressed in the direction of the arrow. I felt a hatred for him. In addition, as shown in Fig. 2, there is a protrusion 13 protruding from the edge of the operating wire insertion groove for bending the curved portion, and this protrusion locally presses the optical fiber bundle and creates a gap between it and other internal components. There was a drawback that the optical fiber bundle could be bent due to being pressed by the fibers. Further, as shown in FIG. 4, the inserted built-in object is tightly inserted into the inner diameter of the flexible tube, and there is an insertion resistance of about 50 g to 200 g when inserting the built-in object into the flexible tube. There is a method of wrapping a thin spiral tube around the outer periphery of the exterior silicon tube of the optical fiber bundle, but since the spiral tube is free to expand and contract,
The lower back does not become strong, and the optical fiber bundle cannot move against the insertion resistance of the built-in object during the bending operation, and if the bending operation is repeated many times, the optical fiber bundle will not be able to move as much as it was once pulled. Since there was no force to push the optical fiber toward the operating section, the optical fiber gradually gathered into the curved portion of the tip and was compressed into an S-shape, which tended to increase the number of folds in the optical fiber.

In view of the above-mentioned conventional drawbacks, the present invention has a thin wall that prevents collapse due to pressure on other built-in objects, prevents pressure on the protruding part of the wire groove edge of the bendable part, and further improves flexibility. It is designed to increase the strength of the waist while transmitting the movement of the optical fiber bundle to the operating section side during bending operations, thereby preventing the optical fiber bundle from buckling, thereby increasing the durability of the optical fiber bundle. The purpose is to provide a thin exterior structure.

The present invention will be explained below with reference to illustrated embodiments.

FIG. 1 is an external view of the endoscope, in which an operating section 1 and a distal end component 2 are connected by a flexible tube 3. A curved portion is provided at the connection portion between the tip component 2 and the flexible tube 3. Figure 2 shows the structure of the curved part.
A short tube 5 with a curved side edge cut out is connected by a caulking pin 6, and as shown in FIG. 10, a water supply channel 11, and an operating wire 12 for bending the curved portion are inserted.

Each of the optical fiber bundles of the image guide 7 and light guide 8, which are made up of a large number of optical fiber strands, are fixed at both ends with annular fittings 14, as shown in FIG. tube 1
5, and both ends of the tube are fixed to the annular metal fitting 14 by adhesive or thread winding. The outer periphery of the silicone tube 15 is further covered with a knitted tube 16 made of a material 17 (FIG. 6) with a flat cross section. The material 17 having a flat cross section is produced by slitting or rolling a wire material with a round cross section.

For example, if a 0.08 mm wire is rolled to a thickness of 0.03 mm, the material 17 with a flat cross section has a width of approximately 0.17 mm.
However, if this rolled material of 0.03 thickness x 0.17 width is used, the wall thickness of the flat knitted wire tube is 0.06 mm, which is equivalent to the overlap of two wires, as shown in Figure 7, and the diameter of the four wires is 0.06 mm. The thickness is 0.12 mm, compared to the thickness of 0.08 mm diameter wire, which is 0.32 mm for 4 wires.
mm can also be reduced. Moreover, when comparing the strength of a 0.03 mm diameter round cross-section wire and a 0.03 mm thick x 0.17 width flat cross-section material, the cross-sectional area related to tensile strength is approximately 6.8 times larger, and the cross-sectional area related to buckling bending and torsion is about 6.8 times larger. The moment of inertia of area is approximately 9 times higher, so even though a knitted pipe with a round cross section and a diameter of 0.03 mm is weak and difficult to use, a knitted pipe made of a material with a flat cross section of 0.03 mm thick x 0.17 mm wide has high strength. is sufficient for above use.
In addition, if the outer diameter of the flexible tube at the insertion part of the endoscope becomes thicker, as in the case of a colon fiberscope, the optical fiber bundle and forceps insertion channel will also become thicker. Since the force, etc. becomes large, if the portion of the optical fiber bundle corresponding to the curved tube portion is double coated with a flat ribbon spiral tube and a flat ribbon knitted tube, it is highly effective in preventing bending damage to the optical fiber bundle even if the thickness is thin.

Moreover, the flat ribbon spiral tube or the thin-walled silicon tube can be placed over the flat ribbon knitted tube to prevent the knitting from loosening, which is highly effective in preventing bending and damage to the optical fiber bundle.

For bronchial fiberscopes and the like, it is necessary to make the outer diameter of the flexible tube as thin as possible. In this case, it is effective to directly cover the built-in optical fiber bundle with a flat ribbon knitted tube.

As described above, the present invention prevents collapse of the flexible tube due to pressure from other internal objects by overturning the knitted tube made of a material with a flat cross section as the exterior of the optical fiber bundle built into the endoscope. The outer structure of the optical fiber bundle prevents pressure on the protruding parts of the wire groove edges.
While it can be made thinner, it has a great effect of increasing the strength of the waist and transmitting the movement of the optical fiber bundle to the operating section during bending operations, preventing buckling of the optical fiber bundle, so it has high practical value. .

[Brief explanation of the drawing]

FIG. 1 is an external view of an endoscope as an embodiment of the present invention.
Figure 2 is an example of the structure of the bendable part, Figure 3 is a diagram showing the mutual relationship between the built-in plastic tube and the optical fiber bundle when the bendable part is curved, and Figure 4 is the arrangement of the built-in parts of the bendable part. 5 is a structural example of a single optical fiber bundle built into an endoscope, FIG. 6 is an enlarged cross-sectional view of an example of the material of the optical fiber bundle coated knitted tube according to the present invention, and FIG. 7 is a sectional view showing an example. FIG. 2 is a partially cutaway partial external view of the knitted pipe according to the present invention. 1: Hand operation section, 2: Tip structure section, 3: Flexible tube, 4: Curved section, 7: Image guide, 8: Light guide, 9: Biopsy tool insertion channel, 10.
11: Water supply/water channel, 12: Operation wire, 13: Operation wire guide section, 14: End ring for binding optical fiber bundles, 15: Thin silicon tube, 16: Knitted tube made of flat material.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. An endoscope in which an optical fiber bundle covered with a knitted tube made of a flat material is inserted into a flexible and curved insertion part extending from a hand operation part having an eyepiece part. 2. An endoscope having a thin-walled tube or a thin-walled spiral tube as a lower coating of a knitted tube coating of an optical fiber bundle according to claim 1 of the utility model registration claim. 3. An endoscope in which the braided tube coating of the optical fiber bundle according to claim 1 of claim 1 of the utility model registration is localized at the bendable portion of the insertion section.