JP3030105B2 - Endoscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope in which a light guide connector at an end of a light guide fiber on an incident side is improved.

[0002]

2. Description of the Related Art In recent years, by inserting an elongated insertion portion into a small-diameter portion such as a blood vessel or a ureter, various treatments can be performed using a treatment tool inserted into a treatment tool channel for observation or as needed. Catheter-type endoscopes are widely used.

In a catheter type endoscope as disclosed in JP-A-2-43513, the light guide connector 1 on the light guide fiber incident end side is as shown in FIGS. I have. That is, the base pipe 2 fills the light guide fiber 3 at a high density, and further prevents heat transmitted to the light guide fiber 3 in order to prevent overheating of the end face of the light guide fiber due to illumination light from a light source device (not shown). A heat conducting member or a heat radiating member (adhesive) 4 is filled in the gap of the light guide fiber 3 so that the heat is released to the base pipe 2. At the other end of the base pipe 2, the boundary with the light guide fiber 3 is fixed with an adhesive 5. This is because the light guide fiber 3 is attached to the base pipe 2
This is to prevent falling off. The end of the base pipe 2 is coated and adhered to the distal end of the outer tube 6, and the distal end of the outer tube 6 is further covered with a buckling tube 7.

[0004]

However, in the conventional example, the light guide fiber in the outer tube is
It consists of a flexible part and a hard part hardened by an adhesive. For this reason, when the outer tube is bent with the operation of attaching and detaching the light guide connector to and from the light source device, bending stress concentrates on a hard portion of the light guide fiber, and the light guide fiber breaks. There was a problem of doing it.

SUMMARY OF THE INVENTION The present invention has been made in view of these circumstances, and has been made to prevent breakage of a light guide fiber in a light guide connector when the light guide connector is attached or detached while maintaining a simple structure as a connector. And then
It is an object of the present invention to provide an endoscope that can always send bright illumination light into the body.

[0006]

In order to achieve the above object, an endoscope according to the present invention is provided with a flexible light guide fiber bundle having a hard end, and an outer periphery of the hard end. The base pipe and the base end face of this base pipe
An adhesive for fixing the outer peripheral surface of the preparative guide fiber bundle, before
A connector pipe provided on the outer periphery of the mouthpiece pipe and having a base end extending to a flexible portion of the light guide fiber bundle;
Wherein coating the light guide fiber bundle, characterized in that a light guide cord having one end extending to the outer periphery of the connector pipe.

[0007]

In the endoscope having this structure, when the flexible tube is bent near the connector when the flexible tube is bent in the vicinity of the connector, no bending stress is applied to the hard portion of the light guide fiber. The guide fiber does not break.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6 relate to an embodiment of the present invention, FIG. 1 is a cross-sectional view of a light guide connector, FIG. 2 is an overall schematic view of a catheter endoscope, FIG.
4 is a sectional view of the first branch, FIG. 5 is a sectional view of the second branch, and FIG. 6 is a comparative sectional view of the light guide connector.

As shown in FIG. 2, the catheter endoscope 9
Is an elongated insertion portion 10 inserted into a living body lumen from the distal end side.
And a first branch portion 11 provided on the base side of the insertion portion 10.
A channel tube 12 and a universal cord 13 divided by the first branch portion 11, a second branch portion 14 provided on the base side of the universal cord 13, and an image guide connector 16 divided by the second branch portion 14. The light guide cord 17 includes an image guide cord 15 and a light guide connector 18.

The channel tube 12 has a channel opening 19 through which various treatment tools are inserted so that water supply, suction, treatment, and the like can be performed. An image guide connector 16 provided at the end of the image guide cord 15 is connected to a camera control unit (not shown) for the operator to view on a monitor, for example, while the end of the light guide cord 17 is connected. The light guide connector 18 provided in the section is connected to a light source device (not shown) for illuminating the front of the distal end portion of the insertion section.

The distal end of the insertion portion will be described with reference to FIG. The insertion portion 10 is made of, for example, a multi-lumen tube 20 made of a flexible resin, and is relatively large in an axial direction.
For example, the image guide fiber bundle 22 has a crescent-shaped mounting hole 21 and a channel hole 24, and an image guide fiber bundle 22 having an objective optical system 22 a on the distal end side in the central axis direction of the mounting hole 21. This image guide fiber bundle 2
Light guide fiber bundles 23, 23 for illuminating the inside of the living body lumen are arranged in the device holes 21 located on both sides of the device 2. The image guide fiber bundle 22 and the light guide fiber bundles 23 in the mounting hole 21 are held by filling with a flexible resin.

Next, the first branch portion 11 will be described with reference to FIG. The first branch portion 11 is provided with a channel hole 24 in the multi-lumen tube 20 forming the insertion portion 10.
The rear side of the tube extends in a tubular shape, and the channel tube 12 is connected to an end of the tubular portion via a connection pipe 25 connected in a watertight manner. Further, the mounting hole 21 of the multi-lumen tube 20 is
4 is opened at the front part of the tubular portion, and the image guide fiber bundle 22 and the light guide fiber bundle 23 are formed by the tubes around the channel hole which are expanded by press-fitting the connection pipe 25 into the multi-lumen tube 20.
Is not under pressure. The image guide fiber bundle 22 and the light guide fiber bundle 23 inserted through the mounting holes 21 are inserted through the universal cord 13.

The connection pipe 25 is connected to the channel hole 24 of the multi-lumen tube 20 and the channel tube 1.
2 are press-fitted, so that both tubes around the connection pipe 25 are expanded by press-fitting. The exposed end 26 of the distal end of the universal cord 13 is connected to the multi-lumen tube 20 which is expanded by press-fitting the connection pipe so that the exposed portion of the image guide fiber bundle 22 and the light guide fiber bundle 23 is not directly pressed by the expansion by the tube. It is located closer to the insertion section 10 than the side end 27. Therefore, breakage of the fiber caused by expansion of the tube due to press fitting of the connection pipe 25 is prevented.

In order to prevent the exposed portions of the image guide fiber bundle 22 and the light guide fiber bundle 23 from being directly pressed by the expansion of the tube, the distal end 26 of the universal cord 13 is multi-lumen expanded by press-fitting the connection pipe 25. By being located closer to the insertion portion 10 than the end portion 27 on the tube 20 side, the first branch portion 1
Even if the connecting pipe 25 is bent by applying a bending stress to 1, the bending of the connecting pipe 25 is suppressed by the universal cord 13, so that the image guide fiber bundle 22 and the light guide fiber bundle 23 in the universal cord 13 The connection pipe 25 is not broken by being pressed by bending.

The first branch portion 11 extends beyond the fiber exposed portion end 28 of the multi-lumen tube 20 and the expanded portion end 29 of the channel tube 12 expanded by press-fitting the connection pipe 25, respectively.
0, and this protective tube 30 is
The multi-lumen tube 20, the channel tube 12, and the universal cord 13 are covered and adhered over both ends of the protective tube 30 by a heat-shrinkable tube 31 having an inner peripheral surface provided with a heat-welding adhesive. Therefore, the multi-lumen tube 2 is formed by the heat-shrinkable tube 31.
0 and the channel tube 12 and between the multi-lumen tube 20 and the universal cord 13 are coated and adhered, the protective tube 30 entangles the heat-welding adhesive with the internal organs, or heat-shrinks the tube 31. Does not squeeze the internal organs. The protective tube 30
Is made of a material with a high softening point such as PTFE,
The heat-shrinkable tube 31 is made of a material such as polyolefin that shrinks at a temperature whose softening point is sufficiently lower than that of the protective tube 30.

Further, the heat-shrinkable tube 31 covers the multi-lumen tube 20, the channel tube 12, and the universal cord 13 beyond both ends of the heat-shrinkable tube 31 by a heat-shrinkable tube 32 made of silicon or the like having high flexibility. ing. Therefore, the heat-shrinkable tube 32 prevents buckling against bending stress from the heat-shrinkable tube 31 to the multi-lumen tube 20 and from the heat-shrinkable tube 31 to the universal cord 13 and the channel tube 12.

Next, the second branch portion 14 will be described with reference to FIG. The second branch 14 branches the universal cord 13 extending from the first branch 11 into an image guide code 15 and a light guide code 17. When inserting the image guide fiber 22 and the light guide fiber 23 in the universal cord 13 into the image guide cord 15 and the light guide cord 17, the second branch part 14 exposes each fiber bundle similarly to the first branch part 11. ing. The protection tube 33 is provided at a position where the fibers between the image guide cord 15 and the light guide cord 17 from the universal cord 13 are exposed,
The image guide cord 15 and the light guide cord 17 are covered in a cantilever manner while covering each of the cords beyond the exposed fiber portion of the cord.
The universal cord 13, the image guide cord 15, and the light guide cord 17 are covered and adhered over both ends of the protective tube 33 by a heat-shrinkable tube 34 having an inner peripheral surface coated with a heat-welding adhesive. Therefore, when the heat shrink tube 34 covers and bonds the universal cord 13 and the image guide cord 15 and the universal cord 13 and the light guide cord 17 with the heat shrinkable tube 34, the protective tube 33 is bonded by heat welding. The agent is prevented from entangled with the internal organs, and the heat-shrinkable tube 34 does not compress the internal organs. As in the case of the first branch portion 11, the protective tube 33 is made of a material having a high softening point such as PTFE, and the heat shrinkable tube 34 has a softening point sufficiently higher than that of the protective tube 33 such as polyolefin. Use a material that shrinks at a low temperature.

Further, the heat-shrinkable tube 34 is extended over both ends of the heat-shrinkable tube 34 by a highly flexible heat-shrinkable tube 35 made of silicon or the like.
Is coated. Accordingly, the heat-shrinkable tube 35 is connected from the heat-shrinkable tube 34 to the universal cord 13 and from the heat-shrinkable tube 34 to the image guide cord 15.
In addition, buckling against bending stress applied to the light guide cord 17 is prevented.

Next, the light guide connector 18 will be described with reference to FIG. The light guide connector 18 extends the light guide fiber bundle 23 from the rear end of the flexible light guide cord 17 and connects the end portion of the extended light guide fiber bundle 23 to a light source device (not shown). In order to prevent overheating of the end surface of the light guide fiber due to illumination light from the light guide fiber 23), a heat conducting member or a heat radiating member (not shown) is filled in the gap of the light guide fiber 23 to form a hard portion, while The base pipe 36 is fitted and covered from the rear end to the front halfway. At the other end of the base pipe 36, the boundary with the light guide fiber bundle 23 is fixed with an adhesive 40. This is to prevent the light guide fiber bundle 23 from falling off from the base pipe 36 at the time of assembly. The base pipe 36 is covered by a connector pipe 37 at least to a position beyond the hard portion of the light guide fiber bundle 23, and the distal end side of the connector pipe 37 is covered with the inner circumference of the light guide cord 17 and the light guide fiber bundle 23. It is loosely fitted between the outer circumference. Then, the connector, the pipe 33 and the light guide cord 1
The connection portion with 7 is covered and adhered and fixed by a heat-shrinkable tube 38 having an inner peripheral surface provided with a heat-welding adhesive.
Symbols β and γ in the figure are required lengths as an adhesion allowance provided for adhesive fixing. Further, the heat-shrinkable tube 38 is covered with a highly heat-shrinkable tube 39 made of silicon or the like from the connector pipe 37 to the light guide cord 17, and the light guide cord 1 near the connector is provided.
7 is prevented from buckling. Further, a portion from the end of the connector pipe 37 to the end of the heat-shrinkable tube 39 is formed as a control unit insertion portion. Symbol α in the figure
Is the length of the control unit insertion section.

When assembling the endoscope as described above, the length of the image guide fiber bundle 22 and the light guide fiber bundle 23, which are built-in components, is set so as to always fit in the endoscope. Since the length of the multi-lumen tube 20, the universal cord 13, the image guide cord 15, and the light guide cord 17 vary from member to member, conventionally, the control unit insertion portion length α differs from product to product. However, in this embodiment, the connector insertion portion length α can be set to an arbitrary length by moving the position of the heat-shrinkable tube 39. FIG. 6 shows an example in which the insertion portion length α is changed with respect to FIG.
It is.

The light guide connector 18
The light guide cord 17 is bent with the attachment / detachment operation with the light source device. At this time, since only the flexible portion of the light guide fiber bundle 23 is located inside the light guide cord 17, the light guide fiber bundle 23 bends and follows the bending of the light guide cord 17, so that it is not broken. It should be noted that, besides being a soft portion, the inside diameter of the connector pipe 37 is larger than the inside diameter of the base pipe 36, so that the filling rate of the light guide fiber 23 is reduced, so that the flexibility is further increased.

FIGS. 7 to 9 show examples of the configuration of the distal end of the image guide in the catheter endoscope. FIG.
3 is an enlarged cross-sectional view of the objective optical system at the tip of the image guide of the insertion unit 10. The image guide fiber bundle 22
A conduit-type image fiber formed by bundling thousands to tens of thousands of strands each having a cladding disposed around a core, and sequentially layering a jacket glass 50 and a resin primary coat 51 on an effective pixel portion for performing image transmission. It is. The tip of the image guide fiber bundle 22 is polished, and the primary coat 51 at the tip is peeled off and bonded to an objective lens (heterogeneous medium lens) 52. Since the primary coat 51 is a resin, the primary coat 51 can be easily peeled off with a blade such as a cutter, or can be easily peeled off by wiping off with a solvent which does not affect the jacket glass 50 and the like.

The objective lens 52 and a part of the distal end side of the image guide fiber bundle 22 are inserted into a lens frame 53 and fixed with an adhesive 54.

The peeled portion of the primary coat 51 of the image guide fiber bundle 22 is set to be located closer to the base end than the base end of the lens frame 53. The adhesive 54 is filled up to the tip of the coat 51. That is, the exposed portion of the jacket glass 50 is filled with the adhesive 54.

The objective optical system having the above-described structure is used together with the light guide fiber bundle and the adhesive 5 at the tip of the insertion section 10.
It is fixed at 5. At this time, the portion is fixed with the adhesive 55 from the portion supplemented with the adhesive 54 to a portion on the base end side.

In the case of a multi-component glass, the light guide fiber (not shown) can have a "stiffness" that can be easily pushed into a multi-lumen tube if the fiber is about 50 to 100 μm. Further, when the built-in component is inserted into the multi-lumen tube, the material of the multi-lumen tube is suitably a fluororesin or PVC because the sliding property of the multi-lumen tube with respect to the built-in component greatly affects the assembling workability.

The maximum outer diameter of the objective optical system according to the prior art as shown in FIG. 8 is determined by the conduit part outer diameter + the thickness of the primary coat + the thickness of the lens frame. This is because at least the inner diameter of the lens frame 53 must be set to a diameter that can be accommodated by the primary coat 51 of the image guide fiber bundle 22. In this configuration example, at least the jacket glass 50 can be inserted into the lens frame 53. As a result, the thickness of the primary coat 51 can be omitted from the factor for determining the maximum outer diameter.

If a bending stress is applied to a portion of the image guide fiber bundle 22 where the primary coat 51 is not covered and the jacket glass 50 is exposed, a small crack may be generated in the jacket glass 50 and the jacket glass 50 may be broken at a stroke. . However, in this configuration example, since the objective optical system is hardly covered with the adhesive 54 and the adhesive 55, the jacket glass 50 can be prevented from being damaged.

Further, before the distal end of the light guide fiber bundle is inserted into the multi-lumen tube, the distal end of the bundle is formed into a rod-like shape having a hard portion, and the length of the hard portion is adjusted from the objective optical system to the tip of the primary coat. When the length is longer than the length, the light guide fiber bundle is in a state of supporting the image guide fiber bundle, and the bending strength of the image guide fiber is improved.

FIG. 9 shows another example of the state of adhesion between the image guide fiber and the objective lens 52. As shown in the figure, the adhesive strength is increased by spreading the adhesive 56 over the entire periphery of the joint.

By the way, since the outer diameter of the lens frame, which is the outermost diameter of the objective optical system, can be reduced, the diameter of the insertion portion can be reduced, and the endoscope can be further deepened or narrowed in the living body. Can be inserted.

Further, in this configuration, the primary coat 51 at the tip of the image guide fiber bundle 22 is peeled off and the image guide fiber bundle 22 is bonded and fixed to the lens frame 53, so that the primary coat 51 has poor adhesion like silicone resin. The image guide fiber bundle 22 can be reliably fixed to the lens frame 53 even if it is a material.

[0033]

As described above, according to the present invention, the light guide fiber in the light guide connector is prevented from being broken when the light guide connector is attached / detached while maintaining the simple structure as the connector. This has the effect of always sending bright illumination light into the body.

[Brief description of the drawings]

FIG. 1 to FIG. 6 relate to an embodiment of the present invention,
FIG. 1 is a sectional view of a light guide connector.

FIG. 2 is an overall schematic view of a catheter endoscope.

FIG. 3 is a perspective view of a distal end portion of an insertion portion.

FIG. 4 is a sectional view of a first branch.

FIG. 5 is a sectional view of a second branch.

FIG. 6 is a comparative sectional view of the light guide connector.

FIG. 7 is an enlarged cross-sectional view of the objective optical system showing a tip portion of an image guide in the catheter endoscope.

FIG. 8 is a cross-sectional view showing a conventional example of a distal end portion of an image guide in a catheter endoscope.

FIG. 9 is a partially enlarged cross-sectional view showing another example showing the state of adhesion between the image guide fiber and the objective lens.

10 and FIG. 11 relate to a conventional example, and FIG.
0 is a sectional view of the light guide connector.

11 is an arrow view of the tip of FIG. 10;

[Explanation of symbols]

17 ... Light guide cord 18 ... Light guide connector 23 ... Light guide fiber 36 ... Base pipe 37 ... Connector pipe 38 ... Heat shrink tube 39 ... Heat shrink tube

Claims (1)

(57) [Claims] 1. A flexible light guide fiber bundle having a hard end portion, a base pipe provided on the outer periphery of the hard part, a base end face of the base pipe and an outer portion of the light guide fiber bundle.
An adhesive for fixing the circumferential surface, wherein provided on the outer circumference of the base pipe, a connector pipe having a base end portion extends to the flexible portion of the light guide fiber bundle, covering the light guide fiber bundle, one end of the An endoscope comprising: a light guide cord extending to an outer periphery of the connector pipe;