JP2001333882A - Sheathing structure for image-transmitting material for endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheathing structure for an image-transmitting material for an endoscope which prevents breakages of an image-transmitting material at the bending portion without affecting any functions of the endoscope. SOLUTION: At least the bending portion 2 of an image-transmitting material 21, which is inserted all over the inserting part 1 to transmit observed images obtained by the distal end 3 of the inserting part 1, is sheathed with a pipe 214 made of a superelastic alloy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an exterior structure of an image transmission member of an endoscope.

[0002]

2. Description of the Related Art In general, an endoscope is provided with a curved portion which is bent by remote operation from an operation portion at a distal end portion of a flexible tubular insertion portion, and various built-in components such as a treatment tool insertion channel have a full length inside the insertion portion. And is arranged to pass through.

However, when the bending portion is repeatedly bent,
An image transmission element in an image transmission member (an image guide fiber bundle in the case of an optical endoscope, a signal cable in the case of an electronic endoscope) which is inserted and arranged in parallel with the treatment instrument insertion channel has another image transmission element in the bending portion. A phenomenon of being broken by being squeezed by the built-in object occurs.

[0004] This is a phenomenon that has been known for a long time,
As a countermeasure, for example, Japanese Patent Publication No. 49-26674 to 26676 discloses a technique for preventing the breakage of the image guide fiber bundle by moving the treatment tool insertion channel in the axial direction in conjunction with the bending operation. Has been described.

[0005] However, the treatment instrument insertion channel is the thickest and hardest internal part of the endoscope, and if it is moved in conjunction with the bending operation, the bending operation becomes extremely heavy. The operability becomes extremely poor.

Therefore, conventionally, generally, the arrangement position of the treatment tool insertion channel is fixed in the curved portion so as not to interfere with the image guide fiber bundle, or various reinforcing coatings are applied to the image guide fiber bundle in the curved portion. I was taking measures.

[0007]

However, when the arrangement position of the treatment tool insertion channels is fixed in the bending portion, the treatment tool insertion channels have a large resistance to the bending operation of the bending portion, and the bending operation becomes heavy. There is a drawback that the treatment tool insertion channel is easily broken at the array fixing portion.

Further, if an image transmission member such as an image guide fiber bundle is provided with a reinforcing coating, the insertion portion becomes thicker as a result, so that the pain given to the patient into which the endoscope is inserted increases, and the insertion property increases. The basic performance of the endoscope is reduced.

Accordingly, an object of the present invention is to provide an exterior structure of an image transmission member of an endoscope which can prevent breakage of the image transmission member in a curved portion without affecting various functions of the endoscope. And

[0010]

In order to achieve the above-mentioned object, an exterior structure of an image transmission member of an endoscope according to the present invention is provided by a remote control from an operation unit connected to a base end of a flexible tubular insertion unit. An endoscope in which a bending portion bent by the operation is provided at the distal end portion of the insertion portion, at least an image transmission member inserted through the entire length in the insertion portion to transmit an observation image obtained at the distal end of the insertion portion, A portion located inside the curved portion is covered with a superelastic alloy pipe.

The superelastic alloy may be a nickel-titanium superelastic alloy. Further, the image transmission member may be an image guide fiber bundle or a signal cable.

The image transmission member may be covered with a superelastic alloy pipe over its entire length, or may be covered with a superelastic alloy pipe only in the insertion portion or only in the curved portion.

[0013]

Embodiments of the present invention will be described with reference to the drawings. FIG. 2 shows an endoscope, and a bending portion 2 that is bent by remote control is formed at a distal end portion of a flexible tubular insertion portion 1. The bending portion 2 has a known configuration, and is configured by, for example, rotatably connecting a plurality of node rings with rivets.

A distal end body 3 containing an objective optical system and the like (not shown) is connected and fixed to the distal end of the bending section 2, and the base end of the insertion section 1 is connected and fixed to an operation section 4. The operation section 4 includes a bending operation knob 5 for bending the bending section 2.
Etc. are arranged.

In the insertion section 1 including the bending section 2, an image guide for transmitting an observation image formed by the objective optical system in the distal end main body 3 to the eyepiece section 6 protruding from the operation section 4. The fiber bundle 21 is inserted and arranged over the entire length.

Also, a treatment tool insertion channel 10 made of, for example, a tetrafluoroethylene resin tube for inserting a treatment tool, a light guide fiber bundle 22 for transmitting illumination light, and the like are arranged in line with the image guide fiber bundle 21. And is inserted and arranged in the insertion portion 1 over the entire length.

Reference numerals 10a and 10b denote inlets and outlets of the treatment instrument insertion channel 10, and reference numeral 7 denotes a flexible connection pipe having a connector connected to a light source device (not shown) attached to a tip thereof. In addition, as shown in FIG. 3 showing a cross section perpendicular to the axis of the bending portion 2, air / water tubes 23, 24, etc. are inserted through the insertion portion 1.

FIG. 1 shows a first embodiment of an image guide fiber bundle 21 inserted through an endoscope as described above. Thousands to tens of thousands of optical fibers 211 are provided at both end surfaces. They are arranged in an array.

Each optical fiber 211 is fixed by an adhesive in both end caps 212 and 213, but in the other intermediate portion, each optical fiber 211 is formed to bend independently and flexibly. , Exterior pipe 21
4.

The exterior pipe 214 is formed of, for example, a nickel-titanium superelastic alloy pipe.
The two end caps 212 and 213 are mechanically connected and fixed by caulking. 215 is the caulking part.

The inner cross-sectional area of the outer pipe 214 is preferably about 1.25 to 1.4 times the inner cross-sectional area of the end caps 212 and 213 in order to secure the movement of the optical fiber 211 and to effectively use the space. And the thickness may be about 0.1 to 0.15 mm.

A pipe made of a superelastic alloy such as a nickel-titanium alloy has a very large elastic limit (for example, the strain rate is about 8%, which is eight times that of stainless steel), and a small radius of curvature without crushing when an external force is applied. It easily bends to its original shape when the external force is removed.

The endoscope is used for bronchial examination, for example.
Is small and the radius of curvature of the curved portion 2 is small (approximately 8 to 10 mm), assuming that the inner diameters of both end caps 212 and 213 are 1 mm, the inner diameter of the outer pipe 214 is 1.25 to 1.4 mm. , Can be easily bent to a radius of curvature of 8 to 9 mm without plastic deformation.

Further, the endoscope is used, for example, for gastrointestinal examination, and the insertion portion 1 is thick and the radius of curvature of the curved portion 2 is large (15 to 30).
If the diameter of the inner diameter of both ends 212 and 213 is 2 mm, the diameter of the outer diameter of the outer pipe 214 is 2.5 to 2.8 mm, and it is easy without plastic deformation to a radius of curvature of 16 to 18 mm. You can turn to

Therefore, even when the bending portion 2 and the insertion portion 1 are bent repeatedly and irregularly during the endoscopic examination, the outer pipe 214 can be set to be bent correspondingly without being crushed. The optical fiber 211 of the image guide fiber bundle 21 does not receive any pressure and does not break at all.

The present invention is not limited to the above-described embodiment. For example, as shown in FIG. 4, only the outer pipe 214 at the forward portion of the image guide fiber bundle 21 is made of a superelastic alloy pipe. It may be formed and the rear portion may be covered with a flexible tube 217 such as a silicone rubber tube or a polyethylene tube.

In this case, it is preferable to cover and protect the image guide fiber bundle 21 with an outer pipe 214 made of a superelastic alloy at least at a portion located inside the curved portion 2. If the inside portion is entirely covered with a superelastic alloy pipe 214, the protection of the optical fiber 211 in the insertion portion 1 is completed.

The image guide fiber bundle 2
By using a superelastic alloy pipe for the exterior of the light guide fiber bundle 22 as well as the light guide fiber bundle 22, it is possible to prevent breakage of the optical fiber for lighting. However, at least a portion located inside the curved portion 2 may be covered and protected with a superelastic alloy pipe.

FIG. 5 shows an example in which the present invention is applied to an electronic endoscope. An observation image formed by the objective optical system 200 is picked up by the solid-state image sensor 27, and the observation image pick-up signal is The signal is transmitted by a signal cable 271 that is inserted through the entire length of the insertion section 1 including the inside of the bending section 2.

At least a portion of the signal cable 271 located inside the curved portion 2 is covered and protected by a covering pipe 274 made of a superelastic metal pipe, as in the case of the image guide fiber bundle 21.

The light guide fiber bundle 22
The optical fiber 221 is also exteriorly protected by an exterior pipe 224 made of a superelastic metal pipe.

[0032]

According to the present invention, the image transmission member for transmitting the observation image is provided at least at the portion located inside the curved portion with the superelastic alloy pipe,
Even if the bending portion is repeatedly bent with a small radius of curvature, the exterior of the image transmission member is easily bent without being crushed, so that the image transmission member is prevented from being broken in the bending portion without affecting various functions of the endoscope. Can be.

[Brief description of the drawings]

FIG. 1 is a side sectional view of an image transmission member (image guide fiber bundle) according to a first embodiment of the present invention.

FIG. 2 is a side view of the endoscope according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of a plane perpendicular to an axis in a bending portion of the endoscope according to the first embodiment of the present invention.

FIG. 4 is a side sectional view of an image transmission member (image guide fiber bundle) according to a second embodiment of the present invention.

FIG. 5 is a side sectional view of a distal end portion of an insertion portion of an electronic endoscope according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Insertion part 2 Bending part 21 Image guide fiber bundle (image transmission member) 22 Light guide fiber bundle 211 Optical fiber 212,213 Both ends cap 214 Outer pipe (super-elastic alloy pipe) 217 Flexible tube 271 Signal cable (Image transmission) 274) Exterior pipe (super-elastic alloy pipe)

Claims (7)

[Claims] 1. A distal end of the insertion portion of an endoscope provided with a curved portion which is bent at a distal end of the insertion portion by a remote operation from an operation portion connected to a base end of the flexible tubular insertion portion. An endoscope, characterized in that an image transmission member inserted through the entire length in the insertion portion to transmit the observation image obtained in the above is externally covered with a superelastic alloy pipe at least in a portion located in the curved portion. Exterior structure of the image transmission member. 2. The exterior structure for an image transmission member of an endoscope according to claim 1, wherein said superelastic alloy is a nickel-titanium superelastic alloy. 3. The exterior structure of an endoscope image transmission member according to claim 1, wherein said image transmission member is an image guide fiber bundle. 4. The exterior structure of an image transmitting member of an endoscope according to claim 1, wherein said image transmitting member is a signal cable. 5. The exterior structure of an image transmission member of an endoscope according to claim 1, wherein said image transmission member is exteriorly covered by said superelastic alloy pipe over its entire length. 6. The exterior structure of an image transmission member of an endoscope according to claim 1, wherein said image transmission member is externally enclosed by said superelastic alloy pipe only in said insertion portion. 7. The exterior structure of an image transmission member of an endoscope according to claim 1, wherein said image transmission member is externally enclosed by said superelastic alloy pipe only inside said curved portion.