JP2002085327A - Endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endoscope capable of facilitating the work when assembled, reducing in assembly cost, and preventing burning of a tip cover due to electric discharge even when used together with a high frequency treatment device and having excellent durability. SOLUTION: A size of a cover glass 20 arranged at a tip of an objective lens 17 fixed in a metallic lens frame member 19 is set to such size that covers the whole front face of the lens frame member 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an endoscope used in combination with a high-frequency treatment instrument.

[0002]

2. Description of the Related Art In general, there are techniques disclosed in Japanese Patent Application Laid-Open Nos. 11-32985 and 9-26548 as endoscope technologies for safely using a high-frequency treatment instrument. In this method, an insulating resin material is provided on the outermost part of an elongated flexible tube constituting an insertion portion of an endoscope to be inserted into a lumen, and is provided on a distal end side of the flexible tube. By disposing an insulating rubber member on the exterior part of the curved part and providing an insulating distal cover member on the distal end component disposed on the distal end of the insertion part, the entire insertion part of the endoscope can be used. It is configured to be covered with an insulating member.

FIG. 4 shows the internal structure of a distal end component a disposed at the distal end of an insertion portion in a conventional endoscope. The tip component a is provided with a tip component b made of metal. The distal end member b has at least three holes, ie, a hole c for mounting an observation optical system, a hole for mounting an illumination optical system (not shown), and a hole d for forming a forceps insertion channel.

Further, an observation optical system is mounted in a hole c for mounting the observation optical system in the distal end member b. This observation optical system is provided with an objective lens e and an image transmission fiber f. Here, the objective lens e is disposed at the distal end of the hole c for mounting the observation optical system, and is fixed to the proximal end side of the hole c with the distal end of the image transmission fiber f inserted. . Note that a lens g, which is arranged to be spaced apart from the objective lens e, is adhered and fixed to the tip of the image transmission fiber f.

Usually, the objective lens e of the endoscope has a parallel flat glass, a so-called cover glass h, on the distal end side, and the cover glass h and other lens groups are formed by a metal lens frame member i. To fix it to the metal tip component b.

Here, the front end surface of the cover glass h is disposed substantially on the same plane as the front end surface of the insulating front cover member j covering the outer surface of the metal front constituent member b, or at a position slightly protruding therefrom. ing. For this reason, the distal end side of the metal lens frame member i is also arranged on substantially the same plane as the distal end surface of the insulating distal cover member j. Conventionally, by applying an insulating adhesive k or the like on the end surface on the distal end side of the metal lens frame member i, the metal lens frame member i It is designed to prevent the tip from being exposed.

[0007]

In the above-mentioned conventional construction, when the endoscope is assembled, an insulative adhesive k is placed on the front end surface of the metal lens frame member i having a small external dimension. Since it is necessary to perform a fine work of applying the like, it is troublesome, and the work at the time of assembly is very troublesome.

Furthermore, the portion of the metallic lens frame member i on which the insulating adhesive k or the like is applied on the distal end surface is relatively most insulated in the entire distal end surface of the insertion portion of the endoscope. It is a part with low sex. When such an endoscope is used together with a high-frequency treatment instrument in a state in which water is accumulated on the distal end surface or in water, the high-frequency current flowing when the high-frequency treatment instrument is driven causes the insertion portion of the endoscope to flow due to the moisture. Lens frame member i, which is the least insulating part of the tip surface of
, And may flow intensively around the area, causing a discharge phenomenon. In such a case, the adhesive applied around the lens frame member i is lost due to the discharge, and the insulative tip cover member j itself is also burned by the discharge, so that the insulative tip cover member j is burned. j may need to be replaced and repaired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to facilitate the work of assembling, reduce the assembling cost, and to insulate even when used together with a high-frequency treatment instrument. An object of the present invention is to provide a highly durable endoscope, which can prevent the end cover of the battery from burning due to electric discharge.

[0010]

According to the first aspect of the present invention, a metal tip member is disposed at a tip of an insertion portion inserted into a lumen, and the tip member is an insulating tip cover member. In addition to the end glass, the objective lens is fixed in a metal lens frame member, and the end glass is attached to the distal end component with a cover glass disposed at the distal end. An endoscope having a size set to cover the entire front surface of a lens frame member. According to the first aspect of the present invention, by covering the entire front surface of the lens frame member of the objective lens with the cover glass disposed at the distal end of the objective lens, the metal lens frame member is provided on the distal end surface of the endoscope. It was not exposed. Thus, the fine work of applying an insulating adhesive or the like on the end surface of the metal lens frame member on the front end side is omitted, so that the work at the time of assembly is easy and the assembly cost can be reduced. In addition, even when used in combination with a high-frequency treatment instrument, the insulating end cover is prevented from burning due to electric discharge.

According to a second aspect of the present invention, the cover glass is set to be larger than the diameter of the objective lens and to have the same diameter as the outer diameter of the lens frame member. Is an endoscope. According to the second aspect of the present invention, the cover glass is set to have the same diameter as the outer diameter of the lens frame member, so that the entire front surface of the lens frame member is covered by the cover glass.

According to a third aspect of the present invention, the cover glass has a tapered reduced diameter portion whose outer diameter is reduced from a distal end side toward a base end side, and a frame inner periphery of the lens frame member. The endoscope according to claim 1, further comprising a tapered engagement portion that engages with the reduced diameter portion on a surface. According to the third aspect of the present invention, when connecting the cover glass and the lens frame member, the tapered reduced diameter portion of the cover glass and the tapered engagement portion of the lens frame member are connected. The engagement allows the outer diameter of the cover glass and the lens frame member to be easily adjusted.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a schematic configuration of the entire endoscope 1 of the present embodiment. The endoscope 1 is provided with an elongated insertion portion 2 to be inserted into a lumen, and a hand-side operation portion 3 connected to a base end of the insertion portion 2.

An eyepiece 4 is provided at the rear end of the operation unit 3. Further, a detachable forceps insertion port / perfusion base 5 and an operation lever 6 are provided on the outer peripheral surface of the operation section 3, and a light guide cable 7 is connected to the operation section 3.

The insertion portion 2 has a flexible portion 8 formed of an elongated flexible tube, and a curved portion 9 connected to the distal end of the flexible portion 8.
And a distal end component 10 provided at the distal end of the curved portion 9. Further, as shown in FIG. 2, an image transmission fiber 11, a forceps insertion tube 12, and an illumination fiber (not shown) are provided inside the insertion portion 2 as shown in FIG.
Is inserted.

FIG. 2 shows the internal structure of the distal end component 10. As shown in FIG. The tip component 10 is provided with a tip component 13 made of metal. This tip constituent member 13
Are formed with at least three holes, that is, a hole 14a for mounting an observation optical system, a hole 14b (not shown) for mounting an illumination optical system, and a hole 14c for forming a forceps insertion channel. The observation optical system 16 is provided in the hole 14a for mounting the observation optical system, the tip of an illumination fiber (not shown) is provided in the hole 14b for mounting the illumination optical system, and the forceps insertion conduit is provided in the hole 14c for forming the forceps insertion channel. The tubes 12 are fixed in a state where the distal ends thereof are inserted.

Further, a cylindrical member 15 is connected to the distal end of the tube 12 for inserting a forceps. On the base end side of the cylindrical member 15, a tube connecting portion 15a to which the distal end of the forceps insertion tube 12 is fitted is formed. The tube connecting portion 15a of the cylindrical member 15
With the distal end of the forceps insertion conduit tube 12 fitted outside, the tube connecting portion 15a of the cylindrical member 15 and the distal end of the forceps insertion conduit tube 12 are fixed by bonding or the like. Note that the distal end side of the cylindrical member 15 is the distal end component 1
3 and is fixed by bonding or the like.

The observation optical system 16 includes an objective lens 17.
And an image transmission fiber 11 are provided. Here, the objective lens 17 is disposed at the distal end of the hole 14a for mounting the observation optical system, and is fixed to the proximal end side of the hole 14a in a state where the distal end of the image transmission fiber 11 is inserted. . In addition, a lens 18 that is arranged to be spaced apart from the objective lens 17 is adhered and fixed to the tip of the image transmission fiber 11.

The objective lens 17 is bonded and fixed in a metal lens frame member 19. Then, while being held by the lens frame member 19, it is adhesively fixed to the distal end side of the observation optical system mounting hole 14a. Here, the inner diameter of the frame member 19 is set to be substantially equal to the outer diameter of the objective lens 17.

Further, a cover glass 20 is provided on the tip side of the objective lens 17. This cover glass 20
Is adhered and fixed to the front surface of the lens frame member 19 of the objective lens 17. The outer diameter of the cover glass 20 is substantially equal to the outer diameter of the frame member 19, and is set to a size that can be inserted into the hole 14a for mounting the observation optical system.
Then, when assembling the endoscope 1, the objective lens 17 and
After the objective lens unit 17A in which the lens frame member 19 and the cover glass 20 are assembled is assembled in advance, the objective lens unit 17A is integrally bonded to the distal end side of the observation optical system mounting hole 14a. It is fixed.

A tip cover member 21 made of an insulating resin or the like is adhered and fixed to the outer surface of the tip component member 13. The distal end cover member 21 has three holes of the distal end component member 13, that is, a hole 14a for mounting an observation optical system,
Holes 21a are provided at positions corresponding to a hole for mounting an illumination optical system (not shown) and a hole 14c for forming a forceps insertion channel, respectively.
To 21c (the holes 21b are not shown). Here, the hole 21a at a position corresponding to the hole 14a for mounting the observation optical system is set to a hole diameter substantially equal to or slightly larger than the outer diameter of the cover glass 20. The distal end cover member 21 of the present embodiment is set to have a thickness such that the distal end surface of the cover glass 20 projects on the same plane as the distal end surface of the distal end cover member 21 or about 0.1 mm.

A distal end portion of a bending tube 22 constituting the bending portion 9 is fixed to the base end side of the distal end member 13 by bonding. An insulating rubber member 23 is provided on the outer peripheral surface of the curved tube 22. The distal end side of the rubber member 23 is fixedly wound around the distal end constituent member 13 by a thread member 24, and is adhesively fixed by applying an adhesive 25. In this embodiment, an example in which the optical fiber 11 is used as the image transmission means has been described. However, the present invention is not limited to this, and an electronic endoscope using a CCD may be used.

Next, the operation of the above configuration will be described.
At the time of assembling the observation optical system 16 in the distal end component 10 of the endoscope 1 of the present embodiment, first, the objective lens 17 is inserted and adhered to the inside of the frame member 19, and at the same time, the distal end side of the objective lens 17 The cover glass 20 is bonded and fixed. At this time, an operation of bonding and fixing the cover glass 20 to the lens frame member 19 is performed in a state where the outer peripheral surface of the cover glass 20 is positioned so as to match the outer peripheral surface of the lens frame member 19 of the objective lens 17. Thereby, the objective lens 17
Then, the objective lens unit 17A in which the three parts of the lens frame member 19 and the cover glass 20 are assembled is assembled in advance.

Further, after the respective adhesive portions of the objective lens unit 17A in which the three components of the objective lens 17, the lens frame member 19, and the cover glass 20 are assembled are dried, the tip optical member 13 is mounted on the observation optical system. The objective lens unit 17A in which these three components are assembled is inserted into the hole 14a, and is fixed by bonding.

After that, the tip cover member 21 is bonded and fixed to the outer surface of the tip component member 13 at last. At this time, the entire front end side of the metal frame member 19 is completely covered by the cover glass 20 and the front end cover member 21, so that the metal frame member 19 is placed on the outer surface of the front end component 10 of the endoscope 1. Will not be exposed. Therefore, there is no portion on the outer surface of the distal end portion 10 of the endoscope 1 where the insulation property is reduced.

Therefore, the above configuration has the following effects. That is, in the present embodiment, the cover glass 20 disposed at the distal end of the objective lens 17 fixed in the metallic lens frame member 19 of the distal end component 10 of the insertion section 2 of the endoscope 1 is attached to the lens frame member. Since the size is set to cover the entire front surface of the front surface 19, the metal lens frame member 19 is not exposed on the front end surface of the front end component 10. for that reason,
Since the work of applying a fine adhesive for applying the adhesive so as to hide the lens frame member 19 at the time of assembling the endoscope 1 can be omitted, the work at the time of assembling the endoscope 1 is simplified and the assembly cost is reduced. Can be lowered.

Furthermore, since the entire front surface of the lens frame member 19 is covered by the cover glass 20, it is possible to prevent high-frequency current from being concentrated near the lens frame member 19 when using the high-frequency treatment instrument. Therefore, even when used together with the high-frequency treatment instrument, the insulating end cover 2
1 can be prevented from burning due to electric discharge, and the durability can be improved.

FIG. 3 shows a second embodiment of the present invention. In this embodiment, the objective lens unit 1 of the endoscope 1 according to the first embodiment (see FIGS. 1 and 2) is used.
7A is modified as follows. The other parts have the same configuration as the endoscope 1 of the first embodiment, and the same parts as those of the endoscope 1 of the first embodiment are denoted by the same reference numerals. Then, the description is omitted.

That is, in the present embodiment, the tapered reduced diameter portion 31 whose outer diameter decreases toward the objective lens 17 is provided on the outer peripheral surface on the base end side of the cover glass 20 of the objective lens unit 17A. It is provided.

Further, the lens frame member 1 of the objective lens 17
9 is set to be longer than the axial length of the outer peripheral surface of the objective lens 17. And this lens frame member 19
A tapered engagement portion 32 that engages with the reduced-diameter portion 31 of the cover glass 20 is formed on the inner peripheral surface on the distal end side of the cover glass 20.

When assembling the objective lens unit 17A of the observation optical system 16 in the distal end component 10 of the endoscope 1 according to the present embodiment, the tapered reduced diameter portion 31 of the cover glass 20 and the frame member 19 are assembled. Tapered engaging part 3
The two are bonded together.

Therefore, in the present embodiment, a tapered diameter-reduced portion 31 is provided on the outer peripheral surface on the base end side of the cover glass 20 of the objective lens unit 17A, and the distal end of the lens frame member 19 of the objective lens 17 is provided. Tapered engaging portion 3 that engages with the reduced diameter portion 31 of the cover glass 20 on the side inner peripheral surface
2, the cover glass 20 and the lens frame member 1
9, the cover glass 20 and the lens are engaged by engaging between the tapered reduced diameter portion 31 of the cover glass 20 and the tapered engagement portion 32 of the lens frame member 19. The outer diameter of the frame member 19 can be easily adjusted. Therefore, there is an effect that the assembling work time of the objective lens unit 17A of the observation optical system 16 can be further reduced, and the assembly cost of the objective lens unit 17A can be reduced.

Further, the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention. Next, other characteristic technical matters of the present application will be additionally described as follows. (Additional Item 1) A cover glass, a plurality of lenses, and a metal lens frame member are fixed to a metal tip body member at the tip of the endoscope insertion section, and the metal body member is insulated by an insulating tip cover member. In the coated endoscope, the diameter of the cover glass is larger than the diameters of the other lenses, and is equal to the outer diameter of the lens frame member.

(Additional Item 2) The cover glass has a tapered portion whose outer diameter decreases from the distal end to the proximal end.
The endoscope according to claim 1, wherein the lens frame member has a tapered portion at the inner diameter portion on the distal end side opposite to the tapered portion.

(Additional Item 3) An objective lens provided at the distal end of the insertion portion for observing the observation object, a metal lens frame member holding the objective lens, and a distal end of the lens frame member coaxially with the objective lens A cover glass disposed on the side of the insertion section is fixed to a distal end main body member provided at the distal end of the insertion portion, and the end body member is covered with a distal end cover member. An endoscope having a diameter larger than the diameter of the lens frame member.

(Prior Art of Supplementary Items 1 to 3) As a technique of an endoscope which can safely use a high-frequency treatment instrument, Japanese Patent Laid-Open No.
There has been a technique disclosed in U.S. Pat. That is, a method in which the outermost sheath of the flexible tube is made of an insulating resin material, the outer sheath of the curved portion is made of an insulating rubber member, an insulating tip cover member is provided at the tip of the insertion portion, and the entire insertion portion is covered with the insulating member. It is.

Normally, the objective lens of the endoscope has a parallel plate glass, so-called cover glass, on the distal end side, and the cover glass and other lens groups are metallized at the distal end of the endoscope by a metal lens frame member. It is fixed to a component. Since the front end surface of the cover glass is substantially flush with the front end surface of the insulating front cover member or at a position slightly protruding, the front end side of the metal lens frame member is also at the front end of the insulating front cover member. It will be located on substantially the same plane as the surface.

(Problems to be Solved by Additional Items 1 to 3)
In the conventional configuration, it is necessary to apply an insulating adhesive or the like to the metal lens frame member so that the metal lens frame member is not exposed to the end surface of the endoscope, and the work at the time of assembly is very troublesome.

The periphery of the metal lens frame member, which is not exposed only by applying an adhesive or the like, is a portion having the lowest insulation property on the distal end surface of the endoscope. When such an endoscope is used together with a high-frequency treatment device in a state where water is accumulated on the distal end surface or in water, high-frequency current flows intensively to the lowest insulating part due to the water, causing a discharge phenomenon. Or As a result, the adhesive applied around the frame member is lost by the discharge, and furthermore, the insulating tip cover itself is burned by the discharge,
In some cases, the insulating tip cover was replaced and repaired.

(Function of Supplementary Items 1 to 3) The cover glass, the plurality of lenses, and the metal frame member are fixed to the metal tip body member at the tip of the endoscope insertion portion, and the metal body member is insulated. In the endoscope covered with the transparent tip cover member, the diameter of the cover glass is larger than the diameter of the other lens and the same diameter as the outer diameter of the frame member. The frame member was not exposed.

(Effects of Additional Items 1 to 3) A cover glass, a plurality of lenses, and a metal lens frame member are fixed to a metal distal end main body member at the distal end of the endoscope insertion portion, and the metal main body member is fixed. In an endoscope covered with an insulating tip cover member, the diameter of the cover glass is larger than the diameter of the other lenses, and the same diameter as the outer diameter of the lens frame member.
Since the lens frame member made of metal is not exposed on the distal end surface of the endoscope, it is not necessary to apply an adhesive to cover the lens frame member during assembly, so that assembly costs can be reduced. Further, when the high-frequency treatment tool is used, the high-frequency current is prevented from being concentrated near the lens frame member, so that it is possible to prevent breakdown due to electric discharge.

[0042]

According to the first aspect of the present invention, the cover glass disposed at the tip of the objective lens fixed in the metal lens frame member is set to a size that covers the entire front surface of the lens frame member. Therefore, the metal lens frame member is not exposed on the distal end surface of the insertion portion. Therefore, it is not necessary to apply a fine adhesive for applying the adhesive so as to cover the lens frame member when assembling the endoscope, and the assembling operation can be simplified and the assembling cost can be reduced.

Further, since the entire front surface of the lens frame member is covered with the cover glass, it is possible to prevent high-frequency current from being concentrated near the lens frame member when using the high-frequency treatment instrument. Therefore, even when used in combination with the high-frequency treatment instrument, it is possible to prevent the insulating end cover from burning due to electric discharge, and to enhance the durability.

According to the second aspect of the present invention, since the cover glass is set to have the same diameter as the outer diameter of the lens frame member, the cover glass covers the entire front surface of the lens frame member. Even when used in combination, it is possible to prevent the insulating end cover from burning due to electric discharge, and to enhance durability.

According to the third aspect of the present invention, at the time of connecting between the cover glass and the lens frame member, the tapered reduced diameter portion of the cover glass and the tapered engagement portion of the lens frame member are connected. By engaging the gap, the outer diameter of the cover glass and the lens frame member can be easily adjusted, so that the assembling work is easy and the assembling cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view showing a schematic configuration of an entire endoscope according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a main part showing an internal configuration of a distal end portion of an insertion section in the endoscope according to the first embodiment.

FIG. 3 is a longitudinal sectional view of a main part showing an internal configuration of a distal end portion of an insertion section in an endoscope according to a second embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of a main part showing an internal configuration of a distal end portion of an insertion section in a conventional endoscope.

[Explanation of symbols]

 2 Insertion part 13 Tip constituent member 17 Objective lens 19 Lens frame member 20 Cover glass 21 Tip cover member

Claims (3)

[Claims] 1. A metal tip component is disposed at a tip of an insertion portion inserted into a lumen, and the tip component is covered with an insulating tip cover member, and a metal lens frame is provided. In an endoscope in which an objective lens is fixed in a member and a cover glass is provided at a distal end thereof, the endoscope is attached to the distal end component member, wherein the cover glass has a size to cover the entire front surface of the lens frame member. An endoscope characterized by having been set. 2. The endoscope according to claim 1, wherein the cover glass is set to have a diameter larger than the diameter of the objective lens and the same diameter as an outer diameter of the lens frame member. 3. The cover glass has a tapered reduced diameter portion whose outer diameter is reduced from a distal end toward a proximal end, and the reduced diameter is provided on a frame inner peripheral surface of the lens frame member. The endoscope according to claim 1, further comprising a tapered engagement portion that engages with the portion.