JPS64882Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an endoscope in which an optical fiber bundle is inserted into a curved insertion section.

[Technical background of the invention and its problems]

Generally, the insertion section of an endoscope is made of a flexible tube connected to a curved tube so that it can be curved. Various internal items such as an optical fiber bundle bound by an exterior tube, an air/water supply tube, a forceps insertion tube, etc. are inserted into the insertion portion. For this reason, for example, when the bending tube of the insertion section is bent, each internal component is forced to move relatively in the axial direction within the insertion section, and at that time, a force is applied to each internal component in the axial direction. Furthermore, as a result of the fact that the interior components come into contact with each other and press against each other, smooth displacement between the interior components is prevented, and the force that should be moving in the axial direction is converted into a force that causes the interior components to buckle. It ends up.

In particular, since the optical fiber bundle itself is soft and has low compression resistance and rigidity, it is relatively easy to cause fatal breakage.

[Purpose of invention]

This invention was made with attention to the above circumstances,
The purpose is to provide an endoscope that can prevent the optical fiber bundle inserted into the insertion section from breaking even if the curved tube of the insertion section is repeatedly bent.

[Summary of the idea]

In this invention, an outer tube is fitted over the optical fiber bundle inserted into the insertion section, and the inner diameter of the outer tube is made smaller in the part corresponding to the curved tube than in the part corresponding to the flexible tube, thereby increasing the durability of the optical fiber bundle. This is an endoscope with improved features.

[Example of idea]

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows an endoscope 1, which includes an operating section 2, an insertion section 3, and a light guide cord 4. The operating section 2 includes a bending operation knob 5, an eyepiece section 6, Forceps port 7, air/water supply button 8, and suction button 9
and is provided. The insertion section 3 is connected to the operating section 2, and includes a flexible tube 11 that curves relatively gently in response to external force, a curved tube 12 that is forcibly curved, and a tip component 13. are sequentially connected from the operating section 2 side.

As shown in FIGS. 2 and 3, the curved pipe 12 has a plurality of short tubular top members 14 arranged in the axial direction as its curved core, and each of the top members 14 is connected to a rivet. Naru pivot pin 15
They are sequentially connected by... The most distal tip member 14 is connected to the distal end component member 13 via a connecting tube 15, and the proximal tip member 14 is connected to the distal end of the flexible tube 11 through a connection cap 16. Further, wire guide rings 17 are attached and fixed to the inner surface of each top member 14 on the upper, lower, left and right sides, respectively, and the wire guide rings 17 on the upper, lower, left and right sides are attached and fixed.
Each of the upper, lower, left and right angle wires 18...
are inserted separately. Angle wire 18...
The tips of each of the angle wires 18 are attached and fixed to the connecting tube 15 on the distal side, and the proximal ends of the angle wires 18 are connected to the wire guide tubes 19 inserted into the flexible tube 11 of the insertion section 3. It is guided through and guided to the operating section 2, and connected to a bending operating mechanism (not shown). Then, the bending operation knob 5 of this operation section 2
By operating the bending operation mechanism, the bending tube 12 is bent by pushing and pulling the upper and lower or left and right angle wires 18. For example, by pulling the upper angle wire 18 and pushing out the lower angle wire 18 without pushing or pulling the left and right angle wires 18, 18, the wire can be bent upward as shown in FIG. Note that each tip of the wire guide tubes 19 is attached and fixed to the connection cap 16, respectively.

Furthermore, various internal items necessary for the endoscope are inserted into the insertion section 3. The internal components include an image guide optical fiber bundle 21, a light guide optical fiber bundle 22, 22, an air/water supply tube 23, a forceps insertion tube 24, a lifting operation wire guide tube 25, etc. There is.

On the other hand, each of the optical fiber bundles 21, 22, 22 is formed by fitting an outer tube 27 around the outer periphery of an optical fiber bundle 26 formed by bundling a large number of optical fibers, and the outer tube 27 is made of a flexible elastic material. It is formed as follows. Further, the exterior tube 27 consists of a portion 27a corresponding to the flexible tube 11 and a portion 27b corresponding to the curved tube 12, with a first tube member 28 forming the portion 27a and a second tube member 28 forming the portion 27b. As shown in FIG. 2, the second tube member 29 is connected and fixed to the first tube member 28 by placing the second tube member 29 over the outer periphery of the first tube member 28. Furthermore, the inner and outer diameters of the second tube member 29 are smaller than the inner and outer diameters of the first tube member 28. Both tube members 28, 29 have the same wall thickness. Furthermore, both tube members 28 and 29 are made of the same material. Therefore, the filling rate of the optical fiber bundle 26 is the portion 27b corresponding to the curved tube 12.
The optical fibers are larger and packed densely to the extent that the optical fibers do not wobble. For this reason, the curved pipe 1
Optical fiber bundle 2 in the portion 27b corresponding to 2
The compression resistance and rigidity of 1, 22, and 22 are increased. In addition,
The inner and outer diameters of each of the tube members 28 and 29 are in their natural state, and when the optical fiber bundle 26 is loaded, they become somewhat larger due to their elasticity. However, the portion 27b corresponding to the curved pipe 12 is still grouped into a smaller diameter. Further, to give a specific example, the sum of the cross-sectional area occupied by the total optical fibers of the optical fiber bundle 26 with respect to the inner hole cross-sectional area of the exterior tube 27 at the time of design (in the natural state) when the optical fiber bundle 26 is not filled. The ratio (filling rate) is 65% or less in the portion 27a corresponding to the flexible tube 11, and 70 to 80% in the portion 27b corresponding to the curved tube 12.
%. In addition, since a small amount of lubricant is actually sprinkled between each optical fiber of the optical fiber bundle 26,
The filling rate including the lubricant becomes higher.

By the way, since each of the top members 14 in the curved tube 12 of the insertion portion 3 is rotatable by the pivot pins 15, they are normally tilted apart as shown in FIG. Moreover, on the inner surface of this top member 14..., the pivot pin 15... and the wire guide ring 17...
protrudes, so that the soft optical fiber bundles 21, 22, 22 often bend and fall when touched. If the angle wires 18 are pushed and pulled in this state to forcibly bend the bending tube 12 to a large extent, the optical fiber bundles 21, 22, 22 located inside the central axis of the insertion portion 3
is compressed as a whole. At this time, each optical fiber bundle 21, 22, 22 is placed on the proximal side (the operating section 2
If the optical fiber does not move smoothly to the side), it will cause severe bending locally, buckling due to the compressive force, and causing the optical fiber to break.

However, as in the above configuration, the filling rate of the portion 27b is increased to make it relatively hard, so the optical fiber can be smoothly moved toward the proximal side without buckling due to compression, and breakage of the optical fiber can be prevented.

On the other hand, as shown in FIG. 4, the wire guide rings 17 are fixed inside the curved pipe 12, so that the internal components are usually less likely to be disturbed. However,
Since the wire guide tubes 19 are not fixed within the flexible tube 11, the internal components can move relatively freely. Therefore, when each interior item moves in the direction of the arrow in FIG. 5, the result is an arrangement as shown in FIG. 6. During this transition, the optical fiber bundles 21, 22, 22 are pinched by other internal components, making it difficult to move in the axial direction. In addition, even if they are not pinched, the flexible tube 11
The packing density inside becomes high, making it difficult to move as well.

However, the optical fiber bundle 2 corresponding to the flexible tube 11
The filling ratio of the optical fiber bundle 26 in the portions 1, 22, and 22 is lower and softer than on the curved tube 12 side. Therefore, the force of the optical fiber bundles 21, 22, 22 pushed in the axial direction by the bending of the curved tube 12 is absorbed by the optical fiber bundles 21, 22, 22 meandering smoothly and gently, and the movement is prevented by other interior components. There is no breakage due to buckling even if the Incidentally, if the part corresponding to the flexible tube 11 is configured with the same filling rate as the part corresponding to the curved tube 12, the movement in the axial direction that occurs in the curved tube 12 can be absorbed quickly at the point where it enters the flexible tube 11. Instead, it gets blocked by other interior components, becomes immobile, and breaks.

In the above embodiment, the exterior tube is constructed by the first and second tube members having different inner and outer diameters, but each part thereof may be formed integrally.

[Effect of idea]

As explained above, in the present invention, the inner diameter of the outer tube in the portion corresponding to the curved tube is smaller than that in the portion corresponding to the flexible tube, thereby increasing the filling rate of the optical fiber bundle and making it harder. When the optical fiber bundle is bent, even if an axial force is applied to the optical fiber bundle, it will not easily move in the axial direction and will not buckle. Since the portion corresponding to the flexible tube is soft, the axial movement transmitted from the curved tube side is gradually absorbed without difficulty, and is not significantly transmitted to the portion that is strongly pressed by other interior items. Therefore, buckling and bending can be prevented even within the flexible tube.

Further, the above configuration can be achieved by simply changing the inner diameter of the outer tube, and the diameter does not need to be increased, so that an endoscope with a thinner insertion section can be provided at a low cost.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a perspective view of the endoscope, FIGS. 2 and 3 are side sectional views of the insertion section of the endoscope, and FIG. 4 is a side sectional view of the insertion section of the endoscope. FIGS. 5 and 6 are longitudinal sectional views of the flexible tube portion. DESCRIPTION OF SYMBOLS 1... Endoscope, 3... Insertion part, 11... Flexible tube, 12... Curved tube, 21, 22... Optical fiber bundle, 26... Optical fiber bundle, 27... Exterior tube.

Claims (1)

[Scope of utility model registration request] In an endoscope in which an optical fiber bundle in which an optical fiber bundle is covered with a flexible exterior tube is inserted into an insertion section formed by connecting a flexible tube and a curved tube, a portion of the exterior tube corresponding to the curved tube. The inner diameter of the outer tube is smaller than the inner diameter of the portion of the exterior tube corresponding to the flexible tube, and the filling rate of the optical fiber bundle in the portion corresponding to the curved tube is increased and the endoscope is configured to be relatively hard. mirror.