JP4648583B2 - Flexible endoscope - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flexible endoscope in which an optical fiber bundle is inserted and disposed in a flexible insertion tube.
[0002]
[Prior art]
If the optical fiber bundle of the endoscope is inserted and arranged in the flexible insertion tube while the optical fibers are simply bundled, the optical fibers will be caught by various parts and bend, so other than the cap part at the end. The part is coated with a flexible coated tube.
[0003]
However, the optical fiber bundle is frequently bent in an irregular direction with a small radius of curvature in the bending portion that is arbitrarily bent by remote operation, and the optical fiber breaks due to pressure applied by the treatment instrument insertion channel or the like. There are many cases where this happens.
[0004]
Therefore, conventionally, the optical fiber bundle is covered with a flexible covering tube over the entire length, and at the portion located in the curved portion, the periphery of the covering tube is surrounded by a spiral tube made of a metal band material and reinforced.
[0005]
[Problems to be solved by the invention]
However, when the coated tube whose outward spread is controlled by the spiral tube is bent with a small radius of curvature, the optical fiber bundle is compressed by the coated tube formed into an accordion shape in the spiral tube, and the movement becomes worse. As a result, optical fiber breakage occurred.
[0006]
Accordingly, an object of the present invention is to provide a highly durable flexible endoscope that does not break the optical fibers of the optical fiber bundle inserted and disposed therein even if the bending portion is repeatedly bent with a small curvature radius. And
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the flexible endoscope of the present invention is an optical fiber in which a large number of optical fibers are bundled in a flexible insertion tube in which a bending portion that can be bent by remote operation is provided near the tip. In the flexible endoscope in which the bundle is inserted and disposed, a portion other than the curved portion of the optical fiber bundle is covered with a flexible coated tube, and the optical fiber bundle is covered with the coated tube in the curved portion. Without being covered with a metal spiral tube.
[0008]
If the spiral tube is covered with a loose gap with respect to the optical fiber bundle, the free movement of the optical fiber is not restricted, and it is effective for preventing breakage.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 2 schematically shows a flexible endoscope, in which a proximal end of a flexible insertion portion flexible tube 1 is connected to an operation portion 4.
[0010]
At the distal end of the insertion portion flexible tube 1, a bending portion 2 that is bent at an arbitrary angle in an arbitrary direction as illustrated by a two-dot chain line by rotating an operation knob 5 provided on the operation portion 4. Are connected, and a flexible insertion tube is formed by the insertion portion flexible tube 1 and the bending portion 2.
[0011]
A distal end body 3 containing an objective optical system (not shown) and the like is connected to the distal end of the bending portion 2, and is used for image transmission inserted into the bending portion 2 and the insertion portion flexible tube 1. The distal end portions of the optical fiber bundle 20, the illumination optical fiber bundle 30, the treatment instrument insertion channel 10, and the like are fixed to the distal end portion body 3.
[0012]
The other end (image exit end) of the image transmission optical fiber bundle 20 is located in the eyepiece 6 projecting from the upper end of the operation unit 4, and the other end (illumination light) of the illumination optical fiber bundle 30. The incident end is located in a connector (not shown) that is connected to the tip of the flexible tube 7 that extends from the operation unit 4.
[0013]
FIG. 1 shows a portion near the tip of the optical fiber bundle 20 for image transmission. The ends of a large number of bundled optical fibers 21 are inserted into a metal pipe-shaped base 22 and bonded with an adhesive. Affixed there, the tip surface is polished. The base 22 is inserted into the tip end body 3 from behind and is fixed.
[0014]
Reference numeral 23 denotes a flexible covering tube made of, for example, a silicon rubber tube or the like that covers the bundle of optical fibers 21 and is covered over almost the entire length except for a portion located in the bending portion 2.
[0015]
In the portion located in the bending portion 2, the bundle of optical fibers 21 is surrounded by the spiral tube 24. The spiral tube 24 is formed, for example, by winding a stainless steel strip spirally with a constant diameter with a slight gap between adjacent strips.
[0016]
The spiral tube 24 is formed in such a diameter that loosely surrounds the periphery of the bundle of optical fibers 21 and has a small gap between the outer surface of the bundle of optical fibers 21 and the rear end portion of the spiral tube 24 is curved. It is in a position slightly inserted from the portion 2 into the insertion portion flexible tube 1.
[0017]
A short spacer tube 25 is fixed to the outer peripheral surface of the covering tube 23 located inside the distal end portion of the insertion portion flexible tube 1 so that the spiral tube 24 does not play in the radial direction on the outer peripheral surface of the spacer tube 25. It is covered with.
[0018]
In the flexible endoscope configured as described above, even if the bending portion 2 is bent with a small radius of curvature, the portion located in the bending portion 2 of the optical fiber bundle 20 for image transmission is the helical tube 24. Is covered with the treatment instrument insertion channel 10 or the like, so that no compression occurs.
[0019]
In the bending portion 2, the bundle of optical fibers 21 is not covered with the covering tube 23 and only the spiral tube 24 is loosely covered. Therefore, the optical fiber 21 is not compressed by the covering tube 23, No breakage occurs in the optical fiber 21.
[0020]
In addition, this invention is not limited to the said Example, For example, you may apply this invention to the optical fiber bundle 30 for illumination.
[0021]
【The invention's effect】
According to the present invention, a portion other than the curved portion of the optical fiber bundle is covered with a flexible coated tube, and in the curved portion, the metal spiral tube is not covered with the optical fiber bundle. Because it is coated, even if the bending part is repeatedly bent with a small radius of curvature, not only is the optical fiber bundle inserted and disposed inside the bending part pressed by the treatment instrument insertion channel, but also the compression by the covering tube. Therefore, the optical fiber does not break and has excellent durability.
[Brief description of the drawings]
FIG. 1 is a side half sectional view of a portion near a tip of an optical fiber bundle for image transmission of a flexible endoscope according to an embodiment of the present invention.
FIG. 2 is a schematic external view of a flexible endoscope according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Insertion part flexible tube 2 Bending part 20 Image transmission optical fiber bundle 21 Optical fiber 23 Cover tube 24 Spiral tube 30 Optical fiber bundle for illumination

Claims (2)

In a flexible endoscope in which an optical fiber bundle in which a large number of optical fibers are bundled is inserted and arranged in a flexible insertion tube in which a bending portion that can be bent by remote operation is provided near the tip,
A portion of the optical fiber bundle other than the curved portion is covered with a flexible coating tube, and the optical fiber bundle is covered with a metal spiral tube without being covered with the optical fiber bundle. A flexible endoscope. The flexible endoscope according to claim 1, wherein the spiral tube is covered with a gap with respect to the optical fiber bundle.

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