JP2960014B2 - Endoscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope, and more particularly, to a configuration of a distal end portion of the endoscope.

[0002]

2. Description of the Related Art Generally, an insertion portion of an endoscope has a distal end portion having an optical element incorporated at the distal end thereof. The distal end portion is made of a metal distal end frame (tip end metallic member). The distal end frame has a hole communicating with a forceps channel provided in the insertion portion, an image guide fiber bundle (or light guide fiber bundle), and an objective lens. A plurality of holes are formed, such as holes for incorporating optical elements such as (or illumination lenses).

[0003] The outer periphery of the end frame is covered with an insulating member made of resin or the like in order to ensure safety during high-frequency treatment. Also in this insulating member, holes are formed in portions corresponding to the holes formed in the end frame, respectively.

[0004]

However, in the case where the distance between the holes at the distal end where the optical element is to be incorporated becomes short, for example, by making the outer diameter of the distal end small, the insulating member is made of resin. It is difficult to manufacture such a device.

In other words, when a plurality of holes that are extremely close to each other are provided in an insulating member by cutting, a thin portion is cut off during the working to form a so-called burr, or when provided by injection molding, A very precise mold is required so that the wall between the holes is accurately formed, which is an obstacle in forming the holes.

In other words, in the past, when the distance between the holes at the tip where the optical element was incorporated was short, considerable difficulty and techniques were required for insulating the tip. The present invention has been made in view of the above circumstances, and an object thereof is to easily and reliably achieve insulation of the distal end even when the distance between the holes of the distal end where the optical element is incorporated is short. It is to provide an endoscope which can do it.

[0007]

According to the present invention, an insulating member is provided outside a tip metal member provided at a distal end of an insertion portion, and the tip metal member and the insulating member are connected to each other. In an endoscope in which an objective lens and an illumination lens are provided in the penetrated small holes, at least two small holes provided in the insulating member are communicated, and a gap is filled with an adhesive between the lenses to form a partition. It is formed .

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show one embodiment of the present invention. As shown in FIG. 2, the endoscope 1 of the present embodiment comprises an endoscope main body including an insertion section 3 and an operation section 2, and the operation section 2 includes an eyepiece 2a and an operation lever 2b. And forceps port 2 communicating with forceps channel 26
c etc. are provided. The insertion portion 3 includes a flexible portion 6, a curved portion 4, and a distal end portion 5, and a jacket tube 8 is fitted on the outer periphery thereof. The bending portion 4 has the same diameter as the bending portion of the existing endoscope, and is moved in two directions (hereinafter, referred to as opposite directions) by the operation lever 2b of the operation portion 2.
One of the two directions is called an UP direction, and the other is called a DOWN direction. ). The bending portion 4 is provided with each bending piece 1 on the UP direction side and the DOWN direction side.
By changing the gap 29 between zero (see FIG. 3 (b)) and restricting the pulling operation of the operation wire 14 connected to the bending piece 10, the maximum bending angle in the UP direction can be reduced. It has become larger than that of.

As shown in FIG. 3 (b), the bending portion 4
For example, the bending pieces 10 are arranged inside the rubber-like outer tube 8 in the longitudinal direction of the insertion portion 3. The bending pieces 10 can be bent freely by connecting their adjacent ends rotatably with rivets 12. Further, a pair of bending operation wires 14, 14, for example, which are arranged to be deviated vertically, are inserted through the insertion portion 3. Each of the bending operation wires 14 is fixed by being separately attached to a wire guide 18 provided at an upper end and a lower end of the bending piece 10 at the forefront. And the bending operation wire 1
4 and 14 are connected to the bending pieces 10 while being supported between the peripheral wall of the bending pieces 10 and the narrowed portion 20 and inserted through the bending portion 4, and disposed on the flexible portion 6. For example, the inside of the flexible portion 6 is guided by a guide pipe (not shown),
Its proximal end is connected to a wire operating mechanism (not shown) operated by the operating lever 2b. Therefore, by operating the operation lever 2b and pulling one of the bending operation wires 14, 14, the bending portion 4 can be bent in that direction. At this time, the other bending operation wire 14 is paid out.

The distal end portion 5 includes a metallic distal end frame (tip metallic member) 24 and an insulating member 22 for high-frequency insulation fitted to the distal end of the distal end frame 24. The distal end frame 24 communicates with the forceps channel 26 so that the forceps and the like can be inserted therethrough, and the observation optical system light such as the distal ends of the image guide fiber bundle 44 and the light guide fiber bundles 42a and 42b and the objective lens 48. Three holes 34,3 to incorporate
6, 37. The three holes 34, 36, 3
7, a third hole 37 described later is located on the DOWN direction side where the maximum bending angle is small, and the third hole 37
The light guide fiber bundle 42b, the tip of which is incorporated therein, is also located on the DOWN direction side where the maximum bending angle is small over the entire length of the insertion portion 3. That is, when the bending portion 4 is bent in the UP direction where the maximum bending angle is large, the light guide fiber bundle 42b is located on the outer circumference side of the bending portion, and at the time of bending, the forceps and the like are connected to the forceps channel 26.
When it is inserted into the inside, it is located at a position where it is pressed by a pushing force of the forceps or the like that resists the insertion resistance.

The foremost bending piece 10 of the bending pieces 10 arranged in the bending portion 4 is fixed to the end frame 24. In order to accommodate the wire guides 18 provided at the upper and lower ends of the foremost bending piece 10, a first notch 74 is provided in the end frame 24 (FIGS. 3B and 3E). reference).

The forceps channel 26 with which the forceps insertion hole 32 communicates includes an outer tube 28 and the outer tube 2.
8 is formed over the entire length of the insertion section 3 by a buckling prevention channel protection coil 30 wound around the outer periphery of the insertion section 8 along the axial direction. Then, a base 58 fitted to the inner peripheral surface at the distal end of the jacket tube 28 is fitted into the forceps insertion hole 32 and is adhesively fixed.

A large-diameter portion 34 b and a small-diameter portion 34 a are formed by a step 35 inside the first hole 34 among the three holes 34, 36, and 37. Objective lens 4 at tip and inside
8 are incorporated. The image guide fiber bundle 44 is formed by bundling a plurality of fibers, and an outer tube 46 is fitted around the outer periphery other than the exposed distal end. The image guide fiber bundle 44 has a base 60 fitted on the exposed outer periphery of the distal end portion. The base 60 is fitted on the inner peripheral surface of the small-diameter portion 34 a of the first hole 34 so as to form a distal end frame. 2
4 is attached. The proximal end side of the image guide fiber bundle 44 is inserted into the flexible portion 6 through the inside of the bending pieces 10 of the bending portion 4, guided into the operation portion 2, and connected to the eyepiece portion 2a. ing.

In the first hole 34 extending forward from the tip of the image guide fiber bundle 44, a cylindrical lens frame 56 and an objective lens 48 held in the lens frame 56 are provided. . The lens frame 56 has the first hole 3
4 while being adhesively fixed to the inner peripheral surface of the large diameter portion 34b.
The distal end of the distal end serves as an extension 56a having a small outer diameter of the frame and protrudes from the first hole 34.

As shown in FIG. 3C, the second hole 36
And a step portion 39 inside each of the third holes 37.
Thus, a large diameter portion 41 and a small diameter portion 43 are formed, and the distal ends of light guide fiber bundles 42a and 42b formed by bundling a plurality of fibers are incorporated. The light guide fiber bundles 42a and 42b have outer sheaths 40a and 40b fitted on the outer circumference, and the exposed distal ends are fitted and fixed to the distal ends of the small diameter portions 43 in the holes 36 and 37, respectively. ((C) of FIG. 3 shows the third hole 3
7 shows a cross section near 7. In addition, the thickness of the outer sheath tube 40b on the outer periphery of the light guide fiber bundle 42b, the tip of which is incorporated in the third hole 37 located on the DOWN direction side where the maximum bending angle is small, is reduced by the pressure from the forceps channel 26 described above. The thickness of the outer tube 40a on the outer periphery of the light guide fiber bundle 42a having its tip incorporated in the second hole 36 is made large enough to withstand a force or the like. The light guide fiber bundle is formed to be slightly thin so that a sufficient quantity of light guide fiber bundles can be inserted into the curved portion 4 so as to satisfy a sufficient light amount for performing endoscope observation.

Light guide fiber bundles 42a and 42b
Is inserted into the flexible portion 6 through the inside of the bending pieces 10 of the bending portion 4, guided into the operation portion 2, and connected to a light source device (not shown). Further, the rear end of the illumination lens 50 is fitted to the inner peripheral surface of the large diameter portion 41 of each of the holes 36 and 37. Therefore, the light guide fiber bundle 42
Reference numerals a and b denote illumination light from the light source device as an illumination lens 5.
0 can be radiated into the body.

According to the optical observation system described above, light from a light source device (not shown)
The light is emitted from the distal end of the insertion portion 3 via the 2a and 42b and is irradiated on the irradiation target, and the reflected light from the irradiation target passes through the objective lens 48 and forms an image on the distal end surface of the image guide fiber bundle 44, The image is transmitted to the eyepiece 2a by the image guide fiber bundle 44, and this eyepiece 2a
The state of the irradiation target can be observed through a.

The insulating member 22 is made of plastic or ceramic or the like, and has a first hole 54 at a position corresponding to the forceps insertion hole 32 of the end frame 24.
The insulating member 22 has the first, second and third holes 34, 36, and 37 formed in portions corresponding to the first, second, and third holes 34, 36, and 37 of the end frame 24. It has a second hole 52 having a continuous shape. On the inner peripheral portion of the second hole 52 at a portion corresponding to the first hole 34,
The extended distal end portion 56a of the lens frame 56 is fitted. The front-end objective lens 48 is fitted in the distal end portion 56a of the lens frame 56. Also, the second
An illumination lens 50 is fitted to the inner peripheral portion of the hole 52 corresponding to the second and third holes 36 and 37 with an adhesive or the like, and the rear end of the illumination lens 50 is The second and third holes 36 and 37 are located in the large-diameter portion 41 and are in contact with the rear end (step 39) of the large-diameter portion 41.

As shown in FIG. 3A, a space between the illumination lens 50 and the objective lens frame 56 is filled with a black adhesive 64 to form a partition wall 61. This prevents direct light from the illumination lens 50 from entering the objective lens 48, and
And the objective lens frame 56 is fixed by the adhesive 64.

Although the insulating member 22 is fixed to the end frame 24 with an adhesive or the like as described above, in order to further ensure safety, a detachment preventing member such as a knock pin as shown in FIG. 66 is mechanically prevented from falling off by being inserted from the insulating member 22 to the front end frame 24. In addition, side holes 70 and 79 are provided at portions where the insulating member 22 and the end prevention member 66 of the end frame 24 are inserted. A portion of the insulating member 22 where the side hole 70 is provided is a thick portion 22a formed to be thick, and a portion corresponding to the thick portion 22a of the end frame 24 is provided with a second notch. 71 are provided. The side hole 70 is filled with a CE agent or the like after inserting the slip-off preventing member 66. As shown in FIGS. 3D and 3E, the relative positions along the axial direction of the first notch 74 and the second notch 71 of the end frame 24 are set to be substantially the same. .

As described above, the endoscope 1 according to the present embodiment uses the insulating member 22 as a means for fixing the distal ends of the illumination lens 50 and the objective lens frame 56 to the insulating member 22.
A second hole 52 having a shape connecting the first, second and third holes 34, 36, 37 is formed in the second hole 52. The second hole 52 is provided with the tip of the illumination lens 50 and the tip of the objective lens frame 56. At the same time, the space between the illumination lens 50 and the objective lens frame 56 is filled with an adhesive 64 to form the partition wall 61, so that the distance between the first and second holes is extremely short. Forming the second and third holes 34, 36, 37 separately,
It is easier than fixing the illumination lens 50 and the objective lens frame 56 here. That is, conventionally, when a plurality of holes having a very short distance between the holes are formed in the insulating member 22 by cutting, a thin portion is cut during the processing to form a so-called burr, or provided by injection molding. In this case, since a highly accurate mold was required so that the wall between the plurality of holes was accurately formed, this was an obstacle in forming the plurality of holes. It is extremely easy to form the second hole 52 at the same time, and at the same time, the filled adhesive 64 is hardened so that the partition wall 61 between the illumination lens 50 and the objective lens frame 56 can be formed.
As a result, the first, second and third holes 3
4, 36, 37 are separately formed, and the same as when the illumination lens 50 and the objective lens frame 56 are fixed here.

Further, by providing a thick portion 22a in the insulating member 22, a side hole 70 is formed in the thick portion 22a to insert the slip-out preventing member 66, and the slip-out preventing member 66 is connected to the outside of the insulating member 22. Since the insulating member 22 is mechanically fixed to the front end frame 24 without being protruded inside the endoscope, the fixing strength can be advantageously increased even in a small-diameter endoscope.

Furthermore, since the relative positions of the first cutout 74 and the second cutout 71 of the end frame 24 along the axial direction are substantially the same, the length of the pull-out preventing member 66 is reduced by the length of the insertion portion built-in member. Can be made as large as possible without affecting the image quality.

Further, the endoscope 1 of the present embodiment operates the operation lever 2b to move the wire 1 on the UP direction side.
When the bending portion 4 is pulled to bend in the UP direction where the maximum bending angle is large, the light guide fiber bundle 42b located on the outer circumference of the bending portion is pulled toward the distal end of the insertion portion 3 and is moved toward the inner circumference of the bending portion. For example, the located light guide fiber bundle 42a is pushed out toward the operation unit 2 by receiving a compressive force. Further, when the bending portion 4 is bent in the DOWN direction where the maximum bending angle is small by pulling the wire 14 on the DOWN direction side, the light guide fiber bundle 42 a located on the outer circumferential side of the bending portion is pulled toward the distal end side of the insertion portion 3. At the same time, the light guide fiber bundle 42b located on the inner peripheral side of the curve receives a compressive force and is pushed out to the operation unit 2 side. As described above, the light guide fiber bundles 42a, 42
b and the like are repeatedly bent in two different directions, and repeatedly receive the opposing forces of the tensile force and the compressive force to move largely in the axial direction of the insertion portion 3. DO with small bending angle
Light guide fiber bundle 42b located on the WN direction side
Intensely in Also, when bending the light guide fiber bundle 42b in the UP direction, when the forceps or the like is inserted into the forceps channel 26, the light guide fiber bundle 42b is strongly pressed by the pushing force of the forceps or the like against the insertion resistance.

However, in the endoscope 1 having the above configuration, the outer tube 40b on the outer periphery of the light guide fiber bundle 42b located on the DOWN direction side where the maximum bending angle is small.
Is thick enough to withstand the compressing force from the forceps channel 26, so that it is repeatedly bent in different directions and breaks even when strongly pressed by the pushing force of the forceps or the like. There is no.

Further, the endoscope 1 of the present embodiment does not increase the thickness of the jacket tube for all the optical fiber bundles in the bending portion 4 as in the prior art, but provides the most resistance. Receiving DOWN direction side light guide fiber bundle 42
b, only the thickness of the outer tube 40b on the outer circumference is increased, and the thickness of the outer tube 40a on the outer circumference of the light guide fiber bundle 42a on the UP direction side is formed slightly thinner. Since the wall thickness is adjusted so that a sufficient amount of light guide fiber bundles can be inserted to satisfy a sufficient amount of light for observation, the outer diameter of the curved portion 4 does not increase.

In the present embodiment, breakage of the light guide fiber bundle 42b is prevented by forming the outer tube 40b on the outer periphery of the light guide fiber bundle 42b on the DOWN direction side having a small maximum bending angle to have a large thickness. However, the outer tube 40b on the outer periphery of the light guide fiber bundle 42b may be doubled to increase its thickness.
Another means for preventing breakage of the optical fiber bundle in the insertion section is shown in FIG.

The endoscope 80 shown in FIG. 4 (a) is configured such that the diameter of the outer tube 40b on the outer periphery of the light guide fiber bundle 42b on the DOWN direction side having a small maximum bending angle is the light on the UP direction side having a large maximum bending angle. It is formed to be larger than the diameter of the outer tube 40a on the outer periphery of the guide fiber bundle 42a, and to reduce the filling rate of the light guide fiber bundle 42b in the outer tube 40b, so that the endoscope observation can be performed in the curved portion 4. A sufficient amount of light guide fiber bundles that can satisfy a sufficient amount of light can be inserted.

Therefore, the endoscope 80 having the above-described configuration can reduce the filling rate of the light guide fiber bundle 42b on the DOWN direction side where the maximum bending angle is small, thereby reducing the axial direction of the light guide fiber bundle 42b during the bending operation. Since the movement is facilitated, the light guide fiber bundle 42b
Can be prevented from buckling and breaking during the operation as much as possible.

Further, the second hole 36 and the third hole 36 are inserted into the curved portion 4 so that a sufficient amount of light guide fiber bundles that can satisfy a sufficient amount of light for performing endoscopic observation can be inserted. Since the diameters of the two tubes 40a and 40b are adjusted, the outer diameter of the curved portion 82 does not increase.

The endoscope 90 shown in FIG.
By increasing the degree of narrowing of the narrowing portion 20 of the bending piece 10 in the bending portion 92, the light guide fiber bundle 42b on the DOWN direction side having a small maximum bending angle is pushed out toward the operation portion 2 and meandered during bending. At this time, the light guide fiber bundle 42b is prevented from climbing over the narrowed portion 20.

Therefore, according to the endoscope 90 having the above-described structure, since the aperture section 20 guides the light guide fiber bundle 42b, the light guide fiber bundle 42b is pushed out toward the operation section 2 and meanders during bending. Even
The light guide fiber bundle 42b does not buckle over the narrowed portion 20 and does not break.

The endoscope 100 shown in FIG.
In this example, every other throttle section 20 is provided on the UP side of the bending piece 10 and the throttle sections 20 are provided on all the pieces on the DOWN side. According to this, the same operation and effect as the endoscope 90 shown in FIG. 4B can be obtained.

The endoscope 110 shown in FIG.
In this example, every other throttle portion 20 is provided on the UP side of the bending piece 10 and every two throttle portions 20 are provided on the DOWN side. In the case where the aperture unit 20 is provided at every other bending piece 10, the light guide fiber bundle 42 in the bending piece 10 which is pushed out toward the operation unit 2 and meanders.
While the meandering of a and 42b becomes tight,
If the aperture unit 20 is provided at every other one of the bending pieces 10, this will be solved.
Is provided on the DOWN side of the bending piece 10 by alternately providing two aperture portions 20, so that when the DOWN side light guide fiber bundle 42b is pushed toward the operation unit 2 during bending, it forms a small arc and meanders. The light guide fiber bundle 42b is not buckled and broken.

When the end frame 24 and the insulating member 22 are miniaturized as the diameter of the endoscope is reduced, it is very difficult to use a pin as the detachment preventing member 66 for preventing the insulating member 22 from falling off. Endoscope 12 shown in FIG.
In the case of 0, this problem can be sufficiently solved.

FIG. 7A shows the vicinity of the distal end of the endoscope 120. 1 to 3 are denoted by the same reference numerals, and detailed description thereof will be omitted. Reference numeral 121 denotes a columnar end frame made of a metal material. Inside the end frame 121, as shown in FIG. 7B, a forceps insertion hole 32 through which the forceps and the like can be inserted in communication with the forceps channel 26. And a first hole 34 in which the objective lens 48, the laser guide fiber bundle 44, and the like are incorporated, and second and third holes 3 in which a light guide fiber bundle (not shown) is incorporated.
6, 37, and a through hole 126 as an air / water supply hole. The through-hole 126 as an air supply / water supply hole communicates with the air supply / water supply pipe 126a, so that air supply / water supply can be performed from the air supply / water supply nozzle 126b.

The insulating member 123 is provided in each of the holes 3 of the end frame 121.
Holes are provided at portions corresponding to 2, 34, 36, 37, and 126, respectively. The rear end of the insulating member 123 is in close contact with the front end of the jacket tube 8. Also,
As shown in FIG. 7D, a claw-like portion 130 is formed at the rear end of the insulating member 123 so as to be loosely fitted into a groove 132 formed in an extra space on the outer peripheral surface of the end frame 121. Then, in order to fix the insulating member 123 to the end frame 121,
The claw-shaped portion 130 is loosely fitted into the groove 132, and the distal end portion of the jacket tube 8 is fitted thereon and adhered and fixed.
May be fastened and fixed to the outer periphery with the grease 124.

According to the above configuration, the insulating member 123 is fastened and fixed to the front end frame 121 by fitting the claw portion 130 into the groove 132 of the front end frame 121. The fixing holding force is larger than in the case where the fixing is performed only by bonding, and it can be prevented from falling off. Further, even if the end frame and the insulating member are miniaturized as the diameter of the endoscope is reduced, the detachment of the insulating member 123 can be easily and reliably prevented without using pins. Further, since the groove 132 is formed in an extra space after the observation optical system such as the objective lens 48 and the fiber 44 is arranged, there is no adverse effect on the observation optical system.

FIG. 8 shows the insulating member 12 shown in FIG.
3 is a modified example of the loose fitting portion between the claw-shaped portion 130 and the groove 132 of the end frame 121. The claw-shaped portion 130 is provided with a projection 140,
When the claw 130 is loosely fitted into the groove 132, the protrusion 14
Numeral 0 designates a business trip from the outer peripheral surface of the end frame 121. According to this configuration, the adhesion between the claw-shaped portion 130 and the jacket tube 8 is improved, and the fastening with the tex 124 can be performed reliably and firmly. FIG.
When the groove 132 of the front end frame 121 is formed as a tapered groove 133 which is gradually inclined toward the inside of the front end frame 121 toward the rear end side, as shown in FIG.
2, the claw-shaped portion 130 is moved toward the front end frame 121.
As a result, the fixing and holding force of the insulating member 123 can be made stronger.

[0040]

As described above, according to the present invention,
Even if the distance between the holes at the tip where the optical element is incorporated is short, insulation of the tip can be achieved easily and reliably.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a bending portion of an endoscope showing one embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of the endoscope of FIG. 1;

3A is a front view of the distal end of the endoscope of FIG. 1, the left half of FIG. 3B is a sectional side view taken along line AOA of FIG. 3A, and FIG.
The right half of (a) is a side sectional view along the line AOB of FIG.
(C) is a cross-sectional view taken along the line CC of (a), (d) is a cross-sectional view taken along the line DD of (b), (e) is an E-line of (b).
It is sectional drawing which follows the E line.

4A and 4B show another means for preventing breakage of an optical fiber bundle in an insertion portion, and FIG. 4A is a cross-sectional view of a bending portion of an endoscope in which a filling rate of a light guide fiber is changed;
FIG. 2B is a cross-sectional view of the bending portion of the endoscope in which the aperture portion of the bending portion is changed.

FIG. 5 is a side sectional view of the endoscope.

FIG. 6 is a side sectional view of the endoscope.

7A is a side cross-sectional view of the endoscope, FIG. 7B is a front view of the distal end frame when no built-in observation optical system is provided,
(C) is a cross-sectional view along the line FF of (a), and (d) is a schematic view showing a state in which the insulating member is mounted on the front end frame.

FIG. 8 is a cross-sectional view showing a state in which an insulating member according to a modification of FIG. 7 is mounted on a front end frame.

FIG. 9 is a side sectional view showing a state in which an insulating member according to a modified example of FIG. 7 is mounted on a front end frame.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Endoscope 3 ... Insert part 4 22 ... Insulating member 24 ... Tip frame (tip metal member) 34, 36, 37 ... Hole 48 ... Objective lens 50 ... Illumination lens 52 ... Hole

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yasuhito Kura 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd. (56) References JP-A-56-145834 (JP, A) ( 58) Fields surveyed (Int.Cl. ⁶ , DB name) G02B 23/26 A61B 1/00 300 G02B 23/24

Claims (1)

(57) [Claims] An insulating member is provided outside a tip metal member provided at a distal end of an insertion portion, and an objective lens and an illumination lens are provided in a small hole penetrating the tip metal member and the insulating member. In the endoscope, at least two small holes provided in the insulating member are communicated, and a gap is filled with an adhesive between the lenses to form a partition.
An endoscope characterized by comprising the.