JPH11262470A - Insertion part of endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insertion part of an endoscope where the outer skin of a flexible pipe is not varied in thickness and hardness but its flexibility is easily and smoothly varied from a midway part thereof. SOLUTION: A wire guide 24 made of a closely wound coil pipe for guiding a control wire 23 passed therethrough is inserted into a flexible pipe 2 fitted over an insertion part. In this case, of the part of the wire guide 24 located within the flexible pipe 2, the range from a proximal end position to a mid position of the flexible pipe 2 is covered with a flexibility-restraining coil pipe 25 formed by winding a metallic wire.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope insertion portion to be inserted into a body cavity or the like.

[0002]

2. Description of the Related Art The insertion portion of a so-called flexible endoscope is constructed by inserting and arranging a built-in member such as an optical fiber bundle in an outer flexible tube. It is necessary to be flexible so as to bend relatively freely along the way, and to make the hand-side portion stiff so that a delicate push-pull operation or the like performed by the operator is transmitted to the tip side.

[0003] Conventionally, the flexibility of the exterior flexible tube itself has been changed on the way by changing the thickness, hardness, and the like of the outermost layer of the synthetic resin outer sheath of the exterior flexible tube depending on the position.

[0004]

The outermost layer of the synthetic resin outer sheath of the outer flexible tube is generally formed by extrusion molding. However, in a manufacturing method in which the thickness and hardness are changed one by one, the outer flexible tube is manufactured. Requires significant time and cost. In addition, when the molding conditions are changed in the middle in such a way, there are not a few cases where the flexibility of each product is varied due to the fluctuation of the molding conditions.

Accordingly, an object of the present invention is to provide an endoscope insertion portion in which flexibility is easily and smoothly changed on the way without changing the thickness and hardness of the outer skin of a flexible tube. .

[0006]

In order to achieve the above object, an insertion portion of an endoscope according to the present invention is provided with a tight winding for inserting and guiding an operation wire into a flexible tube which covers the insertion portion. In the insertion portion of the endoscope in which the wire guide made of a coil pipe is inserted and arranged, of the portion of the wire guide located in the flexible tube, in a range from a base end position of the flexible tube to an intermediate position, It is characterized in that a coil pipe for suppressing flexibility formed by winding a metal wire is fitted.

[0007] The winding pitch of the flexibility suppressing coil pipe may be smaller in the portion near the distal end than in the portion on the base end side, or the winding pitch of the flexible suppressing coil pipe may be smaller. The wire diameter may be smaller in a portion near the distal end than in a portion on the proximal end side.

A plurality of the wire guides may be inserted and arranged in parallel in the flexible tube, and each of the wire guides may be fitted with the coil pipe for suppressing flexibility. The flexibility-suppressing coil pipes may be fitted to the respective wire guides with their tip positions shifted from each other.

Further, the above-mentioned coil pipe for suppressing flexibility is
It may be fixed directly to the wire guide,
Alternatively, the flexibility suppressing coil pipe may be sandwiched and fixed between a pair of stopper members fixed to the wire guide.

[0010]

Embodiments of the present invention will be described with reference to the drawings. FIG. 2 shows an endoscope, in which an insertion portion to be inserted into a body cavity or the like has a bending portion 3 which is bent by a remote operation from the operation portion 1 at a distal end of a flexible portion covered by a flexible tube 2. A distal end main body 4 containing an objective optical system and the like is connected to the distal end of the curved portion 3.

On the surface of the distal end body 4, an observation window 5 for introducing an observation image into the objective optical system, an illumination window 6 for emitting illumination light toward the observation field, a treatment instrument insertion channel outlet 7a, and illustration are omitted. The air supply and water supply nozzles are arranged.

A bending operation knob 8a for bending the bending portion 3 is provided on the operation portion 1 connected to the base end of the flexible tube 2.
8b is disposed, and one of the operation wires in the vertical direction is pulled by the bending operation knob 8a for the vertical direction, and the other operation wire in the left and right direction is pulled by the bending operation knob 8b for the right and left direction. The bending portion 3 can be bent in any direction.

The operation unit 1 also includes an air / water supply operation button 11, a suction operation button 12, and a treatment tool insertion port 7b.
Etc. are arranged. Reference numeral 14 denotes a light guide cable connected to a light source device (not shown).

FIG. 1 shows the flexible tube 2 of the insertion portion. The flexible tube 2 has an outer diameter of about 5 to 15 mm and a length of 50 to
Although it is about 150 cm, it is thicker and shorter than the actual figure for easy understanding.

The flexible tube 2 is constituted by covering a helical tube made of, for example, a metal strip with a mesh tube and covering the outer surface thereof with a sheath of a polyurethane resin or the like. I have. Also, illustration of optical fiber bundles, tubes, and the like inserted and arranged inside is omitted.

The outer shell portion covering the flexible tube 2 may have any structure, but the thickness and hardness of the outer shell may be changed in the middle to change the flexibility of the flexible tube 2 itself. No need.

At the base end of the flexible tube 2, a base connection base 21 for connecting to the operating section 1 is attached.
A distal end connecting tube 22 for connecting the curved portion 3 is attached to a distal end portion of the connecting portion.

The distal end connecting tube 22 is formed of, for example, a stainless steel tube, and has a distal end of a wire guide 24 for loosely inserting and guiding the four operation wires 23 as shown in FIG. The parts are fixed to the inner peripheral surface at intervals of 90 ° by spot welding or silver brazing.

FIG. 1 shows two sets of four sets of operation wires 23 and wire guides 24. The wire guide 24 is formed of a coil pipe in which a stainless steel wire is closely wound with a constant diameter, and each operating wire 23
Is connected to a distal end portion of the bending portion 3.

The proximal end of the wire guide 24 is
Is fixed to a bending operation mechanism frame (not shown) inside, and portions other than both end portions are inserted through the flexible tube 2 in a free state.

Each of the wire guides 24 arranged as described above
In contrast, a coil pipe 25 for suppressing flexibility, which is formed by winding a thin metal wire such as a stainless steel wire into a coil with a constant diameter in a range from the base end position of the flexible tube 2 to the middle position. It is fitted.

The flexibility suppressing coil pipe 25 is fitted to each of the four wire guides 24, and is fixed to each of the wire guides 24 by soldering or the like at the outlet portion A of the base connection base 21, for example. ing. This fixing work is performed before the operation wire 23 is passed through the wire guide 24.

As described above, in the portion near the base end of the flexible tube 2 in which the flexibility suppressing coil pipe 25 is fitted to each wire guide 24, the flexible tube 2 is flexible when bent. The suppression coil pipe 25 acts as a resistor to suppress flexibility, and the push-pull operation of the flexible tube 2 and the like are easily transmitted to the distal end side.

The portion of the flexible tube 2 near the distal end where the flexibility suppressing coil pipe 25 is not fitted to the wire guide 24 is connected to the flexible suppressing coil 2 against the bending operation of the flexible tube 2. Since the pipe 25 has no effect, the pipe 25 has high flexibility (that is, rich in flexibility) and smoothly deforms along the organ shape in the body cavity.

However, if such a structure is simply employed, the flexibility may suddenly change at the middle portion of the flexible tube 2 to make it difficult to use, or the portion may be sharply bent and easily broken.

Therefore, the tip positions of the four flexibility suppressing coil pipes 25 are sequentially displaced, and the flexibility of the insertion portion is gradually changed in the range. Furthermore, the winding pitch of the portion 25a on the distal end side of the flexibility suppressing coil pipe 25 is formed gradually and sparsely toward the front side as shown in an enlarged view in FIG.
Has a very smooth change in the middle.

FIG. 5 shows a flexible tube 2 according to a second embodiment of the present invention.
Are not directly fixed to the wire guide 24, but are fixed to the wire guide 24 by soldering metal annular stoppers 26 which are in contact with both end surfaces of the coil pipe 25 for suppressing flexibility.

With such a configuration, the flexibility suppressing coil pipe 25 is fixed to the wire guide 24 by being sandwiched between the two annular stoppers 26. Other configurations are the same as those of the first embodiment.

FIG. 6 shows a flexible tube 2 according to a third embodiment of the present invention.
The tip 25a of the wire is not changed in pitch interval, but is made thinner in wire diameter to reduce the resistance to bending.
This is the same as the first embodiment, including the structure for fixing the coil pipe 25 for suppressing flexibility with respect to the first embodiment.

As shown in an enlarged view in FIG. 7, a portion 25a on the distal end side of the flexibility suppressing coil pipe 25 is made of a coil pipe material having a small element wire diameter via a connecting pipe 27. It is configured to be connected to the tip of the pipe 25, and may be connected by changing the wire diameter in three or more stages. With such a configuration, the flexibility at the intermediate portion of the flexible tube 2 changes very smoothly.

FIG. 8 shows a portion of a flexible tube 2 according to a fourth embodiment of the present invention. Like the third embodiment, a portion 25a on the distal end side of a flexibility suppressing coil pipe 25 is shown in FIG. As in the second embodiment, the flexibility suppressing coil pipe 25 (the distal end portion 25a is connected between a pair of annular stoppers 26 fixed to the wire guide 24) as in the second embodiment. (Including).

[0032]

According to the present invention, of the portion of the wire guide located within the flexible tube, the flexible portion formed by winding a metal wire around the range from the base end position to the intermediate position of the flexible tube. By fitting the suppression coil pipe, the flexibility of the portion covered with the flexible tube can be easily changed without variation among products without changing the thickness and hardness of the outer skin of the flexible tube. be able to.

The winding pitch of the coil pipe for suppressing flexibility in the portion closer to the distal end than in the portion on the proximal end side is reduced, or the wire diameter of the portion near the distal end in comparison with the portion on the proximal end side is reduced. By making it thin, the change in flexibility can be made smooth, and by fitting the coil pipe for suppressing flexibility by shifting the tip positions of each other with respect to a plurality of provided wire guides. In addition, the change of the flexible tube can be made smooth.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a plane including an axis of an insertion portion flexible tube portion of an endoscope according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing the appearance of an endoscope.

FIG. 3 is a diagram showing a first embodiment of the present invention;
It is a III sectional view.

FIG. 4 is an enlarged cross-sectional view of a distal end portion of the flexibility suppressing coil pipe according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view of a plane including an axis of a flexible tube portion of an insertion section of an endoscope according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view of a plane including an axis of a flexible tube portion of an insertion section of an endoscope according to a third embodiment of the present invention.

FIG. 7 is an enlarged sectional view of a distal end portion of a flexibility suppressing coil pipe according to a third embodiment of the present invention.

FIG. 8 is a sectional view of a plane including an axis of a flexible tube portion of an insertion section of an endoscope according to a fourth embodiment of the present invention.

[Explanation of symbols]

 2 Flexible tube 23 Operation wire 24 Wire guide 25 Flexibility suppressing coil pipe 25a Tip side portion

Claims (7)

[Claims] 1. An endoscope insertion section in which a wire guide formed of a tightly wound coil pipe for inserting and guiding an operation wire is inserted into a flexible tube for covering an insertion section. Of the portion located in the flexible tube, in a range from a base end position of the flexible tube to an intermediate position,
An insertion part for an endoscope, wherein a coil pipe for suppressing flexibility formed by winding a metal wire is fitted. 2. The endoscope insertion section according to claim 1, wherein the winding pitch of the flexibility suppressing coil pipe is smaller at a portion near the distal end than at a portion on the proximal end side. 3. The insertion part for an endoscope according to claim 1, wherein a wire diameter of the flexibility suppressing coil pipe is smaller at a portion near a distal end than at a portion on a proximal end side. 4. The flexible pipe according to claim 1, wherein a plurality of said wire guides are inserted and arranged in parallel in said flexible tube, and said wire guides are fitted with said flexibility suppressing coil pipes.
Or the insertion part of the endoscope of 3. 5. The method according to claim 1, wherein the plurality of flexibility suppressing coil pipes comprises:
The insertion section of an endoscope according to claim 4, wherein the insertion positions of the endoscope are shifted from each other and fitted to each wire guide. 6. The insertion part for an endoscope according to claim 1, wherein the flexibility suppressing coil pipe is directly fixed to the wire guide. 7. The inner pipe according to claim 1, wherein the flexibility suppressing coil pipe is sandwiched and fixed between a pair of stopper members fixed to the wire guide. Endoscope insertion section.