JPH1043130A - Endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endoscope with which a high frequency treatment can be efficiently performed without damaging the assembly or insertion property of the endoscope and without letting a leak current flow from a forceps channel to the internal metal of the endoscope. SOLUTION: At the terminal part of a hole 19 for channel formed at a top end part main body 15 on the side of an insulating cover 14, a projecting part 19a larger than an inner diameter dimension ϕd1 of a channel tube to be inserted to the hole 19 for channel and smaller than an outer diameter dimension ϕd2 of the channel tube 17 is provided while protruded toward the central axis direction of this hole 19 for channel. The top end face of the channel tube 17 arranged at the hole 19 for channel is abutted on the rising face of the projecting part 19a and an insulating adhesive agent 20 is applied between the insulation cover 14, where the inner peripheral side face of the projecting part 19a is positioned, and the top end face of the channel tube 17 so that the metal face of the projecting part 19a at the hole 19 for channel on the side of its inner peripheral surface can be insulated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope for treating a tissue in a patient's body cavity by inserting a high-frequency treatment instrument through a treatment instrument channel and protruding from a metal tip main body.

[0002]

2. Description of the Related Art Generally, an endoscope includes an insertion portion inserted into a body cavity, an operation portion located at a base end side of the insertion portion, which is grasped and operated by an operator, and a side portion of the operation portion. It is mainly constituted by a connector cord provided at an end with a connector extending and detachably connected to a light source device or an image processing device.

The distal end of the insertion section is formed of a metal member provided with an objective lens for observing the inside of the body cavity, an illumination guide for illuminating the inside of the body cavity, and a forceps channel for inserting a treatment tool such as forceps into the body cavity. A tip end body is provided.

When the distal end body is formed of a metal member, when a high-frequency treatment tool such as an electric scalpel is inserted into a body cavity through a forceps channel to perform high-frequency treatment, body fluid or the like comes into contact with an electrode of the high-frequency treatment tool. In such a case, the high-frequency current flowing in the high-frequency treatment instrument leaks to the endoscope, and a sufficient high-frequency current does not flow to the ablation site constituting the treatment section of the high-frequency treatment instrument, and the treatment cannot be performed. there were.

In order to prevent such leakage, it is necessary to cover the exposed portion of the metal of the distal end body with an insulating member. Japanese Patent Publication No. 3-26964 discloses that the distal end of the channel tube is covered with the distal end body. An endoscope joined to an insulating cover is disclosed.

In an endoscope capable of high-frequency treatment, an internal metal is electrically connected to a patient plate side of a high-frequency current, and a current leaking into the internal metal is returned to a high-frequency power supply.

[0007]

However, in the endoscope disclosed in Japanese Patent Publication No. 3-26964, it is necessary to provide an adhesive layer for joining the distal end of the channel tube to the insulating cover. There is a problem that the thickness of the cover is increased, the length of the distal end hard portion of the insertion portion is increased, and the insertability of the endoscope is reduced.

In addition, since the distal end of the channel tube is abutted against the insulating cover, there is a problem that the assembling property is poor due to the insulating cover coming off the distal end body during assembly.

Further, in a small-diameter endoscope, the distal end main body and the node ring are fixed with an adhesive, and the present applicant discloses the distal end main body and the joint disclosed in Japanese Patent Application No. 7-114935. In the structure of the endoscope for high-frequency treatment in which the ring is adhered and fixed, an adhesive layer made of an adhesive is interposed between the distal end body and the node ring, thereby ensuring reliable electrical conduction between the distal end body and the node ring. This is difficult, and the current leaking to the distal end body returns to the high-frequency power supply via the solid-state imaging device, which may cause damage to the solid-state imaging device and disturbance of an image.

The present invention has been made in view of the above circumstances, and does not impair the assemblability or insertability of an endoscope, does not cause leakage current to flow from a forceps channel to an internal metal of the endoscope, and efficiently performs high-frequency operation. An object of the present invention is to provide an endoscope capable of performing a treatment.

[0011]

According to the present invention, there is provided an endoscope comprising: a metal distal end main body provided on a distal end side of an insertion portion; an insulating cover for covering an outer peripheral surface of the distal end main body; A through hole through which the electrically insulating channel tube having an opening on the outer surface of the insulating cover is inserted through the main body and the insulating cover, and is formed on the insulating cover side to protrude in the central axis direction of the through hole. An endoscope provided with a convex portion having a diameter larger than the diameter of the through hole of the channel tube and smaller than the outer diameter of the channel tube, wherein a distal end surface of the channel tube is brought into contact with the convex portion. The inner surface of the convex portion from the distal end surface of the channel tube to the insulating cover is covered with an insulating member.

According to this configuration, it is possible to prevent the high-frequency current flowing through the high-frequency treatment instrument from leaking to the endoscope without impairing the assemblability and insertability of the endoscope.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 7 relate to a first embodiment of the present invention, FIG. 1 is an explanatory view showing a schematic configuration of an endoscope, FIG. 2 is a perspective view for explaining a distal end portion of an insertion portion, and FIG. FIG. 4 is a cross-sectional view illustrating the configuration of the distal end portion, FIG. 4 is a cross-sectional view taken along line AA of FIG. 3, FIG. 5 is an explanatory diagram illustrating a schematic configuration of a bending mechanism of the endoscope, and FIG. FIG. 7 is a cross-sectional view illustrating a schematic configuration of the operation lever.

As shown in FIG. 1, an endoscope 1 includes an insertion section 2 inserted into a body cavity, an operation section 3 serving also as a grip section provided on the proximal end side of the insertion section 2, and an operation section And a connector cord 4 extending from the side of the part 3.

The insertion section 2 has a tip 5 having a tip body, which will be described later, formed of a metal member harder than the tip.
The bending section 6 includes a bending section 6 in which a plurality of bending pieces are connected to bend in the vertical and horizontal directions, for example, and a flexible tube section 7 having flexibility and flexibility.

The operating portion 3 is provided with an operating lever 3a for bending the bending portion 6 in a desired direction. By operating the operating lever 3a, the operating portion 3 is disposed at the tip of the bending portion 6. By pulling the operation wire connected to the first bending piece, the bending portion 6 is bent in the vertical and horizontal directions, so that the distal end surface of the distal end portion 5 can be directed in a desired direction. . In addition, a forceps insertion port 3b for inserting a treatment tool is provided on the distal end side of the operation unit 3.

At the proximal end of the connector cord 4, a light source connecting portion 8a detachably connectable to a light source device as an external device and an image processing detachable to an image processing device as an external device via an electric cable. A connector 8 having a device connection portion 8b is provided. The connector 8 is provided with a high-frequency terminal 9 that is electrically connected to a metal provided inside the endoscope 1, and a cord that returns to a high-frequency power supply is connected to the high-frequency terminal 9. It has become.

As shown in FIG. 2, the distal end 5 of the insertion portion 2
On the distal end surface 5a, an objective lens 11a constituting an observation optical system 11 for observing a part to be examined, a lens cover 12a constituting an illumination optical system 12 for illuminating the part to be examined, and a forceps channel 13 communicating with the forceps insertion opening 3b. Opening 13a is provided. Reference numeral 14 denotes a resin insulating cover that covers the distal end surface of the distal end body and the outer peripheral portion on the distal end surface side.

As shown in FIG. 3, a distal end portion 5 is provided with a distal end portion main body 15 formed of a metal columnar member. A lens frame 16 for holding a plurality of lenses constituting the observation optical system 11 and an illumination light guide (not shown) constituting the illumination optical system 12 are provided inside the distal end body 15.
Also, a plurality of through-holes for an optical system, a through-hole for a channel 19, and the like are provided as a plurality of through-holes respectively corresponding to a flexible channel tube 17 having flexibility, which constitutes the forceps channel 13. I have.

The front end face of the lens frame 16 is disposed so as to be recessed from the surface of the insulating cover 14, and an insulating adhesive is provided between the lens frame 16 and the insulating cover 14. 20, the front end surface of the lens frame 16 is insulated.

At the end of the through hole 19 for channel formed on the tip end body 15 on the insulating cover 14 side, it projects toward the center axis direction of the through hole 19 for channel and is inserted into the through hole 19 for channel. Channel tube 17
The projection 1 formed larger than the inner diameter φd1 of the inner hole and smaller than the outer diameter φd2 of the channel tube 17.
9a is provided.

The distal end surface of the channel tube 17 disposed in the channel through hole 19 is in contact with the rising surface of the convex portion 19a, and the insulating cover 14 on which the inner peripheral side surface of the convex portion 19a is located. An insulative adhesive 20 is applied to the recess between the end of the channel tube 17 and the metal surface on the inner peripheral surface side of the projection 19a of the channel through hole 19 is insulated.

A helical channel coil 2 made of a metal member is provided around the outer periphery of the channel tube 17 except for a part of the distal end side of the channel tube 17.
1 is fitted outside. At this time, the distal-end-side channel tube 2 in which the channel coil 21 is not externally fitted.
2 and the central axis 2 of the bending portion side channel tube 23 in which the channel coil 21 is fitted.
3a, the center axis 22a of the distal end side channel tube 22 is curved.
The distal end portion 5 is made thinner by displacing it so as to be closer to the center side of the endoscope by a distance d from the center axis 23a of the endoscope.
Note that the distal-end-side channel tube 22 and the curved-portion-side channel tube 23 are smoothly displaced.

A connecting member 24 formed of a pipe member is fitted on the distal end main body 15.
A first node ring 61 constituting the foremost portion of the curved portion 6 is fitted to the outside.

The bending portion 6 is provided with a first node ring 6 from the distal end side.
1, second node ring 62, third node ring 63. . . And the first node ring 61 and the second node ring 62
Are connected to the second node ring 63 by a rivet 25 so as to be rotatable, and the adjacent node rings behind the second node ring 62 are similarly rotated by the rivet 25 between the adjacent node rings. It is movably connected.

The connecting member 24 and the plurality of node rings 61, 6
2,63. . . Is covered with a mesh tube 26, and the outer periphery of the mesh tube 26 is further covered with an outer sheath tube 27 having an insulating property. The outer tube 27 is wound around the tip of the outer tube 27, and the outer tube 27 is fastened and fixed to the connecting member 24.

A plurality of ring-shaped wire receivers 30 are provided in the first node ring 61 so as to correspond to the operation wires 31, and tips of at least two operation wires 31 are fixed to the wire receiver 30. Have been. This operation wire 31
Is formed by twisting a plurality of thin metal wires.

Reference numeral 32 denotes an imaging unit main body, and a cover glass 33 provided behind the objective optical system 11 and a solid-state imaging device 34 provided at an image forming position of the objective optical system 11 are made of metal. And is disposed at a predetermined position. From the solid-state imaging device 34, a signal cable 36 formed of a coaxial line is connected to the image processing device connection portion 8b.
Extending toward.

As shown in FIG. 4, a plurality of node rings 61, 62, 63. . . Is formed in the first node ring 61 of the curved portion 6 formed by connecting the first and second connecting members 24, and the first node ring 61 is externally fitted to a predetermined position in the connection member 24. When fixed, the joint hole 6
A through hole 24a for a connection member communicating with 1a is formed.

When the connecting member 24 and the first node ring 61 are externally fixed to the distal end main body 15 in a predetermined state, the through-hole for the intermediate ring is formed in the distal end main body 15. A circular hole 15a communicating with the connection member 61a and the connecting member through hole 24a in a straight line is formed.

That is, the connecting member 24 is externally fitted at a predetermined position of the distal end body 15, and the first node ring 61 is externally fitted at a predetermined position of the connecting member 24, so that the through-hole for the node ring is provided. 61a, the through hole 24a for the connection member, and the circular hole 15a are coaxially arranged to form the concave portion 40. Then, by filling the recess 40 with a conductive adhesive 41 as an electric conduction means in which metal powder is mixed,
The tip body 15, the connection member 24, the first node ring 61,
The operation wires 31 are electrically connected. In the case where the insulating adhesive 20 or the like is attached in the recess 40, for example, the adhesive 20 is removed in advance, and then the conductive adhesive 41 is filled. Reference numeral 12b is an illumination light guide.

As shown in FIG. 5, one end of an operation wire 31 is fixed to a first node ring 61 which is one of a plurality of node rings forming the curved portion 6 of the endoscope 1. On the other hand, the other end of the operation wire 31 is axially symmetrically fixed to a pulley 41 provided in the operation section 3. The pulley 41 and the operation lever 3a are integrated with each other, and are connected rotatably about a rotation shaft 43 protruding from the frame 43.

The frame 43 is fixed in the operation section 3. When the operation lever 3a is rotated, the pulley 41 integrated with the operation lever 3a is rotated, and the operation wire 31 is rotated. Tow. When the operation wire 31 is pulled, the bending portion 2 is bent from a linear state shown by a two-dot chain line in a desired direction. As shown in the drawing, one end of a lead wire 44 passing through the inside of the connector cord 4 is connected to a frame 43 fixed via a shaft 42 to a pulley 41 to which the operation wire 31 is fixed, The other end is electrically connected to the high frequency terminal 9. As a result, the tip body 1
5, connection member 24, first node ring 61, operation wire 31,
The pulley 41, the frame 43, the lead wire 44, the high-frequency terminal 9, and the high-frequency power supply (not shown) are electrically connected to form a feedback circuit having extremely low impedance.

As shown in FIG. 6, in the curved portion 2 before the outer tube 27 is covered, a sealing agent 46 is applied over the entire periphery of the rear side edge of the insulating cover 14. Therefore, the distal end of the outer tube 27 covering the outer circumference of the mesh tube 26 and the first node ring 61 is connected to the insulating cover 14.
When the endoscope is assembled in contact with the rear side edge of the endoscope, the watertightness of the contact portion between the insulating cover 14 and the outer tube 27 is ensured by the sealant 46.

As shown in FIG. 7, the knob portion 47 of the operation lever 3a comprises a knob body 47a made of resin and a metal lever frame 4 inserted inside the knob body 47a.
7b.

That is, the knob portion 47 is composed of a knob main body 47a made of resin and the lever frame 4 inserted into the resin member.
7b is integrally formed by insert molding.

Reference numeral 48 denotes a lever cover made of resin, and together with the knob portion 47, a lever frame 47 is provided.
b covers the outer surface except the back surface.

A projection 49 provided on the back surface of the lever cover 48 is fitted in a through hole 47c provided in the lever frame 47b, and the tip of the projection 49 is deformed by heat. By doing so, the lever cover 48 is fitted and fixed to the lever frame 47b.

Further, the lever frame 47b is fixed to the rotating shaft 42 by a metal fixing screw 51.
The fixing screw 51 is provided with a flange 51a.

The shaft hole 4 provided in the lever cover 48 is provided.
8a is located coaxially with the rotating shaft 42 and the fixing screw 51 in a state where the operating lever 3a is assembled to the rotating shaft 42, and has an inner diameter slightly larger than the outer diameter of the flange 51a of the fixing screw 51. The bottom surface of the resin cover 52 is in contact with the fixing screw 51, while the side surface of the cover 52 is fitted in the shaft hole 48a.

As described above, the inner peripheral surface of the through hole for the channel, which is a through hole formed in the tip end body, is larger than the inner diameter of the channel tube and smaller than the outer diameter of the channel tube. When the channel tube is inserted into and fixed to the rising surface of the projecting portion, the inner peripheral surface of the projecting portion is covered with an insulating adhesive. The inner circumferential surface of the forceps channel can be insulated without increasing the thickness and without reducing the adhesive strength between the insulating cover and the distal end body. In this way, the distal end rigid portion of the insertion section is insulated without lengthening, and the high-frequency current flowing through the high-frequency treatment instrument inserted into the forceps channel of the endoscope is prevented from leaking to the internal metal of the endoscope. To prevent.
In addition, since the insulating cover is prevented from being detached from the distal end body at the time of assembling, assemblability is greatly improved.

A connecting member that fits over the tip body;
By filling the concave portion formed when the first node ring externally fitted to the connection member is assembled in a predetermined state with a conductive adhesive, the distal end main body, the connection member, the first node ring, the operation A wire, pulley, frame, lead wire, high-frequency terminal, and high-frequency power supply can be electrically connected to form a feedback circuit with extremely low impedance. As a result, an excessive leakage current does not flow from the forceps channel to the internal metal of the endoscope, and high-frequency treatment can be performed efficiently. Further, even if a minute leak current flows into the internal metal of the endoscope, the leak current does not pass through the solid-state imaging device and returns to the high-frequency power supply, so that damage to the solid-state imaging device and image disturbance do not occur. .

FIGS. 8 and 9 relate to a second embodiment of the present invention. FIG. 8 is a cross-sectional view illustrating another configuration of the distal end portion. FIG. It is explanatory drawing which shows the process which sequentially fits outside. The members having the same configuration as the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In this embodiment, as shown in FIG. 8, the channel opening 55 provided on the insulating cover 14 and the convex portion 19a provided on the tip end body 15 are coaxial, and the inner diameter of the channel opening 55 The size and the inner diameter of the projection 19a are formed to be substantially the same. A tubular insulating tube 56 made of resin is fitted into the channel opening 55. At this time, the inner peripheral surface of the convex portion 19a is insulated by arranging the proximal end surface of the insulating tube 56 to be in contact with the distal end surface of the channel tube 17. The outer diameter of the insulating tube 56 substantially matches the inner diameter of the projection 19a, and the inner diameter of the insulating tube 56 substantially matches the inner diameter of the channel tube 17.

As shown in FIG. 9, in this embodiment, the distal end body 15, the connecting member 24, the first node ring 61
Are provided with projections 57, 58 and 59, respectively, which serve as electrical conduction means.

That is, the distal end main body 15 is provided with a first projection 57 projecting from the outer peripheral surface of the distal end main body 15 and having an integral or thin pin inserted into the distal end main body 15. In addition, the connecting member 24
Is provided with a second projection 58 which is formed by notching an edge portion of the second projection and slightly bending it in the central axis direction. Furthermore, the first
Cut off the edge of this first node ring 61 in the node ring 61,
Third projection 5 slightly bent in the direction of the central axis
9 are provided.

As described above, the protrusions 57, 58, and 5 are provided on the distal end body 15, the connection member 24, and the first node ring 61, respectively.
9, the base end of the distal end body 15 to which the insulating cover 14 is externally fitted and adhered so that the connecting member 24 and the first node ring 61 are externally fitted to the distal end body 15. When the first connecting ring 24 is externally fitted to the base portion of the connecting member 24 and adhesively fixed by externally fitting the connecting member 24 to the portion, the first 1
The protrusion 57, the second protrusion 58 provided on the connection member 24, and the third protrusion 59 provided on the first node ring 61 allow the surface of the distal end body 15, the connection member 24, and the first node ring 61 to be formed. The applied adhesive layer is scraped off, and the tip end body 15
And the connection member 24 and the first node ring 61 are electrically connected.

As described above, by inserting the insulating tube into the channel opening of the insulating cover and arranging the proximal end of the insulating tube in contact with the distal end surface of the channel tube, the thickness of the insulating cover is reduced. The inner circumferential surface of the forceps channel can be reliably insulated without increasing the thickness and without reducing the adhesive strength between the insulating cover and the distal end body. With this, the inner peripheral surface of the forceps channel can be insulated simply by performing the relatively easy operation of inserting the insulating tube into the insulating cover, thereby greatly improving the workability.

Further, since the distal end main body, the connecting member and the first node ring are provided with projections, respectively, when the connecting member is externally fitted to the distal end main body and the first node ring is externally fitted to the connecting member. At this time, each projection is the tip body, connection member,
By scraping off the adhesive layer of the first node ring,
The distal end body, the connecting member, and the first node ring can be electrically connected without performing the operation of removing the adhesive layer.
Thereby, the work of removing the adhesive becomes unnecessary, and the workability is improved. Other functions and effects are the same as those of the first embodiment.

The first projection 57 and the second projection 58
As for the above, at least one of the protrusions may be provided, and an adhesive layer is provided on a surface corresponding to the provided protrusion.

FIGS. 10 and 11 relate to a third embodiment of the present invention. FIG. 10 is a sectional view of a curved portion at a first node ring portion.
FIG. 11 is an explanatory view showing another method of conducting the tip body, the connecting member, and the first node ring. Note that members having the same configuration as the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In this embodiment, as shown in FIG. 10, the connecting member 24 externally fitted to the distal end body 15 and the first node ring 61 externally fitted to the connecting member 24 are arranged at predetermined positions. Instead of filling the recess 40 formed by coaxially disposing the through-hole 61a for the node ring, the through-hole 24a for the connecting member, and the circular hole 15a with a conductive adhesive, FIG.
A metal pin 60 serving as an electric conduction means indicated by reference numeral 1 is press-fitted. The pin 60 has a polygonal column shape, and the diameter of the circumscribed circle of the pin 60 is slightly larger than the inner diameter of the recess 40.

With the above configuration, the polygonal pin 6 is inserted into the recess 40 formed by arranging the distal end main body 15, the connecting member 24 and the first node ring 61 at predetermined positions.
0, the ridge line 60 of the pin 60 is
Due to “a”, the adhesive layer adhered to the inner peripheral surface in the concave portion 40 is scraped off to conduct electricity.

As described above, when the polygonal pillar-shaped pin is pressed into the concave portion, the ridge line of the pin removes the adhesive adhering to the inner peripheral surface in the concave portion, and the distal end main body, the connecting member, and the first member are removed. 1
Can be electrically connected to the node ring. Thereby, the work of removing the adhesive becomes unnecessary, and the workability is improved. Other functions and effects are the same as those of the above-described embodiment.

It should be noted that the present invention is not limited to only the above-described embodiments, and various modifications can be made without departing from the spirit of the invention.

By the way, conventionally, a cleaning brush has been used for cleaning the inside of a conduit such as an endoscope. For example,
In the cleaning brush disclosed in Japanese Patent Publication No. 2-29853, a flexible core material is inserted into a base end of a brush portion formed by holding a bristle member on a brush forming wire. The coil is formed by connecting and fixing the loosely wound end portion of the coil sheath.

FIG. 12 shows an example of the endoscope cleaning brush formed as described above. As shown in FIG.
Is composed of, for example, a brush forming wire 72 formed by twisting a soft wire, and a bristle member 73 screwed between the brush forming wires 72. In the case of the brush part 71, a substantially spherical tip 74 is fixed to the tip of the brush forming wire 72 by soldering or the like in order to prevent fraying and improve the insertability of the tip. The hand-side end of the brush portion 71 is connected to a coil sheath 75 formed of a coil.

The coil sheath 75 is formed by a loosely wound portion 75a on the front end side and a densely wound portion 75b on the rear end side, and the tightly wound portion 75b is formed as shown in FIG. A coil shaft 76 is inserted. The coil shaft 76 includes a wire-shaped core material 76a and the core material 76a.
and a close-wound coil 76b formed of an elastic wire wound around the outer periphery of a. A loop portion 77 is formed by projecting a proximal portion of the coil shaft 76 from a rear end of the coil sheath 75.

The loop 77 of the coil shaft 76
Is inserted together with the coil sheath 75 into an inner hole 78a formed in the operation section 78, and is integrally fixed by an adhesive or the like.

The base end 72 of the brush forming wire 72
a is inserted into the distal end portion of the loosely wound portion 75a of the coil sheath 75 and is integrally fixed by a fixing member such as solder 79. The distal end of the coil shaft 76 inserted into the tightly wound portion 75b of the coil sheath 75 is integrally fixed to the rear end of the loosely wound portion 75a of the coil sheath 75 by solder 79 or the like.

The cleaning brush 70 constructed as described above
Is inserted into the conduit of the endoscope, and the inside of the conduit can be cleaned by moving the brush part 71 forward and backward. Since the cleaning brush 70 is fixed to the rear end of the loosely wound portion 75a with solder 79, when the cleaning brush 70 is inserted into the conduit of the endoscope and cleaned by moving forward and backward, a tensile force is applied to the coil shaft 76. Or compressive force or bending stress is repeatedly applied.

In particular, at the rear end of the loosely wound portion 75a fixing the coil sheath 75 and the coil shaft 76, when a portion where the flexibility of the coil sheath 75 changes passes through a curved conduit, , The bending stress generated by the large bending of the loosely wound portion 75a is intensively applied, and there is a risk of breaking. For this reason, a stress is unlikely to concentrate on the fixed portion between the coil sheath 75 and the coil shaft 76 during use, and a sheath structure having excellent durability of the coil sheath 75 has been desired.

As shown in FIGS. 13 (a) and 13 (b), the coil shaft 76 of the cleaning brush 70A of the present embodiment has a coil 76 made of an elastic member on the outer periphery of a wire core 76a.
b is wound tightly.
“a” is provided in order to give the entire coil shaft 76 an appropriate waist strength. Therefore, as compared with the case where the coil shaft 76 is constituted by only the coil 76b which is closely wound in a coil shape without providing the core material 76a, the compressive force, the tensile force, the bending stress, etc., which are received when the cleaning brush 70A is operated. The waist strength suitable for the external force can be imparted to the coil sheath 75.

The tip 7 of the coil shaft 76
6c protrudes to the middle of the loosely wound portion 75a of the coil sheath 75, and the core material 76a and the tightly wound coil 76
The tip is fixed with solder 79 or the like in order to reduce the fray with b.

Further, the coil shaft 76 is integrally fixed to the coil sheath 75 by solder 79 at the rear end of the loosely wound portion 75a.

As described above, the distal end portion 76c of the coil shaft 76 is projected to the middle of the loosely wound portion 75a of the coil sheath 75, and the coil shaft 7 at the rear end of the loosely wound portion 75a.
6 and the coil sheath 75 are fixed and the cleaning brush 70A is fixed.
The bending stress generated when the cleaning brush 70A is inserted into the curved conduit of the endoscope and the loosely wound portion 75a bends greatly following the curved conduit is generated by:
It is dispersed to the rear end of the loosely wound portion 75a that fixes the coil sheath 75 and the coil shaft 76, and to the boundary where the flexibility of the coil sheath 75 changes depending on whether or not the coil shaft 76 is inserted. Other configurations are the same as those of the embodiment shown in FIG. 12, and the same members are denoted by the same reference numerals and description thereof will be omitted.

As described above, since the fixed portion between the coil sheath and the coil shaft is displaced from the boundary portion of the coil sheath whose flexibility changes depending on whether or not the coil shaft is inserted, the loosely wound portion is formed. It is possible to prevent a bending stress generated when a large bend follows a bent conduit from being concentrated on a fixed portion between the coil sheath and the coil shaft. As a result, the durability of the coil sheath is greatly improved, and it is possible to provide a sheath structure in which the stress is less likely to concentrate on the fixed portion between the coil sheath and the core material during use, and the durability of the coil sheath is improved.

Incidentally, the core material 76a is replaced with the one shown in FIG.
As shown in (b), a stranded wire 80 may be used. That is, the tip 80 of the stranded wire 80
a protrudes to the middle of the loosely wound portion 75a of the coil sheath 75, and the tip portion 80a is fixed with solder 79 so that the stranded wire 80 is not frayed during use. On the other hand, the stranded wire 80 is integrally fixed to the coil sheath 75 by solder 79 at the rear end of the loosely wound portion 75a. Other configurations are the same as those of the embodiment shown in FIG. 13, and the same members are denoted by the same reference numerals and description thereof will be omitted.

As described above, when the cleaning brush composed of the stranded wire as the core material is inserted into the bent pipe of the endoscope, the loosely wound portion is generated when the bend follows the bent pipe and largely bends. The bending stress is different between the rear end of the loosely wound portion fixing the coil sheath and the stranded wire and the boundary where the flexibility of the coil sheath changes depending on the presence or absence of the stranded wire. Bending stress does not concentrate on the fixing portion with the wire, and the durability of the coil sheath is greatly improved.

The present invention is not limited to the cleaning brush, but includes various treatment tools for endoscopes having a sheath structure composed of a coil sheath in which a flexible core material is inserted. Needless to say, the present invention is also applied to a cleaning brush in a pipe other than for medical use.

The fixing between the core member and the coil sheath is not limited to fixing by soldering, but may be fixing by brazing, fixing with an adhesive, or fixing members such as welding.

Further, the core material may be a closely wound coil other than a stranded wire, a multi-layer coil, or other materials.

[Appendix] According to the embodiment of the present invention described in detail above, the following configuration can be obtained.

(1) A metal tip body provided on the tip side of the insertion portion, an insulating cover covering the outer peripheral surface of the tip body, and a metal penetrating through the tip body and the insulating cover. A through hole into which an electrically insulating channel tube having an opening on the outer surface of the insulating cover is inserted, and a diameter larger than the diameter of the through hole of the channel tube formed on the insulating cover side, protruding in the center axis direction of the through hole. In an endoscope provided with a convex portion having a diameter smaller than the outer diameter of the channel tube, the distal end surface of the channel tube is fixed by contacting the convex portion with the distal end surface. An endoscope in which the inner peripheral surface of the convex portion up to the insulating cover is covered with an insulating member.

(2) The endoscope according to appendix 1, wherein the insulating member is an insulating adhesive.

(3) The endoscope according to appendix 1, wherein the insulating member is a tubular member made of resin.

(4) A metal tip main body provided at the distal end of the insertion portion, and a metal node ring which is fitted to the proximal end of the distal end main body and adhered and fixed to the distal end main body. An endoscope comprising: an endoscope provided with an electric conduction unit that electrically connects the distal end main body to the node ring.

(5) The endoscope according to appendix 4, wherein the electric conduction means is a conductive adhesive.

(6) The endoscope according to appendix 4, wherein the electric conduction means is a projection provided on at least one of the distal end body and the node ring.

(7) The endoscope according to appendix 4, wherein the electric conduction means is a metal pin.

(8) In a sheath structure in which a coil shaft having a flexible core material inserted therein is connected to a coil sheath, a loosely wound portion is provided at the tip of the coil sheath, and the coil shaft is provided in the loosely wound portion. And a sheath structure for fixing the coil shaft at the rear end of the loosely wound portion.

(9) The sheath structure according to attachment 8, wherein the core material is a stranded wire.

(10) The sheath structure according to attachment 8, wherein the core material is a close-wound coil.

(11) The sheath structure according to attachment 8, wherein the core material is a multi-strip coil.

(12) The sheath structure according to attachment 8, wherein the fixing between the core material and the coil sheath is performed by soldering.

(13) The sheath structure according to attachment 8, wherein the core material and the coil sheath are fixed by brazing.

(14) The sheath structure according to attachment 8, wherein the core material and the coil sheath are fixed by welding.

(15) The sheath structure according to attachment 8, wherein the core material and the coil sheath are fixed with an adhesive.

[0090]

As described above, according to the present invention, high-frequency treatment can be efficiently performed without leaking current from the forceps channel to the internal metal of the endoscope without impairing the assemblability and insertability of the endoscope. Can be provided.

[Brief description of the drawings]

FIGS. 1 to 7 relate to a first embodiment of the present invention, and FIG. 1 is an explanatory diagram showing a schematic configuration of an endoscope.

FIG. 2 is a perspective view illustrating a distal end portion of an insertion portion.

FIG. 3 is a cross-sectional view illustrating a configuration of a distal end portion.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is an explanatory diagram showing a schematic configuration of a bending mechanism of the endoscope.

FIG. 6 is an explanatory view showing a configuration of a bending portion before covering the outer tube.

FIG. 7 is a cross-sectional view illustrating a schematic configuration of an operation lever.

8 and 9 relate to a second embodiment of the present invention,
FIG. 8 is a cross-sectional view illustrating another configuration of the distal end portion.

FIG. 9 is an explanatory view showing a process of sequentially fitting the connecting member and the first node ring to the distal end main body.

10 and 11 relate to a third embodiment of the present invention, and FIG. 10 is a cross-sectional view of a bending portion at a first node ring portion.

FIG. 11 is an explanatory view showing another method of conducting the tip end body, the connecting member, and the first node ring;

FIG. 12 is a diagram illustrating a conventional configuration of a cleaning brush.

FIG. 13 is an explanatory view showing a configuration of a cleaning brush.

FIG. 14 is an explanatory view showing another configuration of the cleaning brush.

[Explanation of symbols]

 15: Tip body 17: Channel tube 19a: Protrusion 20: Insulating adhesive

Claims (1)

[Claims] 1. A metal tip body provided on the tip side of an insertion portion, an insulating cover covering an outer peripheral surface of the tip body, and an insulating cover penetrating through the tip body and the insulating cover. A through hole into which an electrically insulating channel tube having an opening on the outer surface of the cover is inserted, and a diameter larger than the diameter of the through hole of the channel tube formed on the insulating cover side, protruding in the central axis direction of the through hole. In an endoscope provided with a convex portion having a diameter smaller than the outer diameter of the channel tube, the distal end surface of the channel tube is fixed by abutting the convex portion, and is insulated from the distal end surface of the channel tube. An endoscope, wherein an inner peripheral surface of a convex portion up to a cover is covered with an insulating member.