JP3142949B2 - 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 having an insertion portion formed by inserting an optical tube incorporating an objective optical system into the inner tube of an insertion portion main body comprising an outer tube and an inner tube.

[0002]

2. Description of the Related Art Various types of endoscope insertion sections have been known. Of these, the actual application was 57-6465
The insertion portion of the endoscope disclosed in Japanese Patent Publication No. 3 and the like has a triple tube structure in which an optical tube incorporating an objective optical system is inserted into the inner tube of the insertion portion main body including an outer tube and an inner tube. .

An illumination optical system is provided in a gap between the outer tube and the inner tube of the insertion portion of the triple tube structure by being integrally fixed to the outer tube and the inner tube. I have. An optical tube is inserted into the inner tube from the near side and fixed.

Further, the optical tube can be removed from the inner tube when necessary. For example, when the lens of the objective optical system in the optical tube is damaged, the optical tube is damaged by extracting the optical tube from the inner tube. Lens can be repaired.

[0005]

Since the cross-section of the inner tube has conventionally been circular (true circle), an optical tube inserted into the inner tube and an objective optical system arranged in the optical tube have been known. Had to be designed so that it could be inserted into this circular inner tube. In this case, in particular, there is a problem in that the design of the objective optical system is largely restricted, and desired optical performance cannot be sufficiently obtained. In particular, this problem is serious for a side-view or rear-view endoscope in which an objective lens is arranged in a special state.

The present invention has been made in view of the above circumstances. It is an object of the present invention to improve the repairability of an objective optical system and to provide a high degree of freedom in designing the objective optical system. An object of the present invention is to provide an endoscope capable of sufficiently obtaining the optical performance of the endoscope.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to an insertion unit comprising an outer tube and an inner tube. In an endoscope provided with a portion, the cross-sectional shape of the inner tube,
At least a part of the objective optical system can be projected from a side of the optical tube, and the objective optical system has a different shape other than a circle into which the projected optical tube can be inserted and retracted.

[0008]

Since at least a part of the objective optical system can protrude from the side of the optical tube, the degree of freedom in designing the objective optical system is increased. Further, by forming the cross-sectional shape of the inner tube into a different shape other than a circle into which the optical tube from which the objective optical system projects can be freely inserted and retracted, the objective tube can be inserted without increasing the outer diameter of the insertion portion, that is, the outer tube. An optical tube incorporating an optical system can be inserted into or removed from the inner tube.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show an embodiment of the present invention. As shown in FIG. 1C, the endoscope 1 of the present embodiment
Is composed of an insertion section 3 and a main body section 9. The main body 9 is provided with an eyepiece 42 into which the insertion section 3 can be inserted, for example, for observing a state inside the body, and is connected to a light guide 40 connected to a light source device (not shown).

As shown in FIG. 1A, the insertion portion 3
The insertion tube main body is composed of the outer tube 2 having a perfectly circular cross section and the inner tube 4 having an elliptical cross section. The optical tube 6 incorporating the objective optical system 20 is inserted into the inner tube 4. Fixed. The optical tube 6 can be moved freely in the inner tube 4 by releasing a fixing means (not shown), and can be removed from the inner tube 4.

A first closing member 8 for closing the opening of the distal end of the outer tube 2 is fixed to the distal end of the outer tube 2 by a method such as soldering, silver brazing, welding, or bonding. Further, the outer tube 2 has a notch 5 which is notched in a state of being opened to the side.
have. The notch 5 reaches the first closing member 8 provided at the tip of the outer tube 2, and is formed as a whole as a step having an opening surface parallel to the axial direction of the outer tube 2.

A bottomed cylindrical second closing member 14 for closing the opening of the distal end of the inner tube 4 is fitted to the outer peripheral surface of the distal end of the inner tube 4 inserted into the outer tube 2 by soldering or the like. ing. The second closing member 14 is arranged at a fixed distance from the first closing member 8 in the distal end of the outer tube 2 where the cutout 5 is located, and the outer surface of the proximal end of the second closing member 14 is Notch 5
By fixing the outer tube 2 and the inner tube 4 on the distal end side of the insertion portion 3 by fixing to the inner surface on the side.

The second closing member 14 has a notch so that an outer surface portion facing the notch portion 5 is flush with an opening surface of the notch portion 5. Part 7
Are formed. A cover glass 18 as an observation window is attached to the opening 7 via an attachment member 16.

In the gap between the outer tube 2 and the inner tube 4,
The light guide fiber 10 connected to the light source device via the light guide 40 is loaded. The light guide fiber 10 has a gap between the outer tube 2 and the second closing member 14 and a gap between the first closing member 8 and the second closing member 14 on the distal end side of the insertion portion 3. It is loaded so that the illumination light can be radiated to the outside through the opening of the notch 5. The light guide fiber 10 is integrally fixed to the outer tube and the inner tube.

An optical tube 6 inserted through the inner tube 4.
The objective optical system 20 incorporated therein includes, as shown in FIG. 2, a lens 26, a prism 24, and a front lens 22. The rear lens 26 is fitted on the inner surface of the front end of the optical tube 6, and the prism 24 and the front lens 22 project from the front end of the optical tube 6. Further, the front lens 22 protrudes to the side of the optical tube 6 with its incident surface facing backward so that desired optical performance can be sufficiently obtained.

As can be seen from the arrangement of the front lens 22,
The objective optical system 20 is for realizing a rear view, and reflects the object light incident on the front lens 22 through the cover lens once by the reflecting surface 23 of the prism 24, To the relay system and eyepiece system. The object light transmitted to the relay system and the eyepiece system is transmitted to the eyepiece section 42 of the endoscope 1 as an observation image and observed.

The optical tube 6 in which a part of the objective optical system 20 (the front lens 22 in this embodiment) projects from the side, is inserted into the inner tube 4 having a circular cross section. Can not. Although the optical tube 6 can be inserted into the inner tube 4 by increasing the diameter of the inner tube 4, increasing the diameter of the inner tube 4 necessarily increases the outer diameter of the outer tube 2. This is not preferable in reducing the diameter of the insertion portion 3.

However, in the case of the endoscope 1 of the present embodiment, the inner tube 4 can move the optical tube 6 from which the objective optical system 20 projects from the side freely, while maintaining the diameter of the endoscope 1 small. Its cross-sectional shape is elliptical over the entire length so that it can be inserted (see FIG. 1B). That is, by making the inner tube 4 into an elliptical shape that is long in the radial direction in which the front lens 22 protrudes, the optical tube 6 moves forward and backward within the inner tube 4 without increasing the outer diameter of the insertion portion 3, that is, the outer tube 2. Free movement can be secured.

As described above, the endoscope 1 of the present embodiment.
The cross-sectional shape of the inner tube 4 is different from a circular shape in which at least a part of the objective optical system 20 can protrude from the side of the optical tube 6 and can penetrate the optical tube 6 from which the objective optical system 20 protrudes freely. Due to the different shape, The degree of freedom in designing the objective optical system 20 is increased, and an optimal design for obtaining desired optical performance becomes possible.

2. Optical tube 6 incorporating objective optical system 20
Can be inserted into the inner tube 2 from the main body 9 side of the endoscope 1 or the optical tube 6 can be removed from the inner tube 2. Therefore, repair due to breakage of the objective optical system or the like can be easily performed. 3. In particular, it becomes very easy to design an objective optical system for side or rear view. 4. Since the objective lens can be brought close to the cover glass 18,
Even if the angle is widened, the field of view due to the cover glass 18 is not lost.

The cross-sectional shape of the inner tube 4 is not limited to an ellipse, but may be a shape other than a perfect circle, such as a diaper, a triangle, and a rectangle.
What is necessary is just to select suitably according to the aspect of the objective optical system 20 which protrudes from the optical tube 6. Further, the objective optical system 20 is not limited to a lens system, and may be an image fiber, a CCD, or the like.

By the way, as in the present embodiment, an image in which the object light is reflected an odd number of times becomes a mirror image (back image) and is observed at the eyepiece 42. The objective optical system 50 for rear view shown in FIG. 3 is also an example. The objective optical system 50 includes a lens 56, a prism 54, and a front lens 52, and converts the object light incident on the front lens 52 to the reflection surfaces 51, 53 of the prism 54 and the reflection surface 55 of the lens 56.
Are reflected three times in total. In the endoscope 50 shown in FIG. 4, the outer surface of the insertion section 66 is finished in a satin finish. That is, FIG. 4B is an enlarged view of the outer surface of the insertion portion 66. As shown in the drawing, the outer surface of the insertion portion 66 has a matte concave portion 66a and a convex portion 66b continuously. Is formed. The insertion portion 66 may be a chrome-plated nickel-white pipe, a non-plated one, or a gold-plated stainless steel pipe.

As described above, when the surface of the insertion portion 66 is matted so that the surface of the insertion portion 66 is coated with the lubricant 68 (see (1) of FIG. 4), the lubricant 68 is used.
Is uniformly inserted into the insertion portion 6 irrespective of the unevenness of the surface of the insertion portion 66.
When the insertion portion 66 is inserted into a patient's body (see FIG. 5) while the body tissue 70 is in close contact with the surface of the insertion portion 66, the lubricant 68 is at least indented on the surface of the insertion portion 66. The lubricant 68 remaining in the recess 66a flows into the space between the protrusion 66b and the tissue 70 little by little when the insertion portion 66 is inserted into the body. The frictional resistance between them is continuously reduced.

When the lubricant 68 is not used (FIG. 6)
However, since the surface of the insertion portion 66 is uneven, the in-vivo tissue 70 comes into contact only with the projection 66b on the surface of the insertion portion 66. Therefore, the contact area between the insertion portion 66, the surface, and the tissue 70 is smaller than when the surface of the insertion portion 66 is smooth. For this reason, the frictional resistance when inserting the insertion portion 66 into the patient's body is reduced, and it becomes easy to insert the insertion portion 66 into the body.

FIG. 7 shows the receive sheath 80.
The reject sheath 80 is configured by inserting a mandolin 82 into a sheath including an insertion portion 86 and a main body 84. Further, the distal end 84a of the insertion portion 86 is cut obliquely.

Conventionally, the distal end portion 82a of the mandolin 82 projecting from the distal end 84a of the insertion portion 86 is formed in a shell shape as shown in FIG. 8, so that the distal end portion 82a can be inserted into a bent biological conduit such as the urethra. Sex was bad. That is, the distal end portion 82a of the mandolin 82 was caught at the bent portion of the living body duct, and the mandolin 82 could not be properly inserted through the living body duct.

In order to solve such a problem, the resect sheath 80 shown in FIG. 7 has an oblique cut shape in which the distal end portion 82a of the mandolin is bulged outward in a state substantially in line with the oblique shape of the opening edge of the distal end 84a of the insertion portion 86. It is formed in. Accordingly, when the resect sheath 80 is inserted into, for example, the urethra, the distal end portion 82a of the mandolin 82 passes through the bent portion of the urethra along the bent portion of the urethra, so that the distal end portion 82a of the mandolin 82 is Can be avoided.

FIG. 9 shows the intermittent sheath 90. The intermittent sheath 90 has an insertion portion 91.
And a main body 92. The main body 92 is provided with a water supply mouthpiece 93 and a drainage mouthpiece 100 communicating with the inside of the insertion portion 91. The communication between the water supply base 93 and the inside of the insertion section 91 and the communication between the drainage base 100 and the inside of the insertion section 91 are controlled by a switching valve 94 mounted on the main body 92.

As shown in FIG. 9B, the switching valve 94 has an outer peripheral surface 95 formed in a tapered shape.
2, the communication hole 101 provided in the outer peripheral surface 95 of the valve 94
It matches with any of the 0 inner holes.

Conventionally, as shown in FIG. 10, the tip of the base member 97 is pressed against the rear end of the valve 94 while the base member 97 is being fastened to the main body 92 by the fastening member 96, thereby forming a tapered valve outer peripheral surface 95. While being pressed against the corresponding tapered portion 103 on the inner surface of the main body 92, the gap between the base member 97 and the rear end of the valve 94 pressed against the base member 97.
Although the watertightness between the valve 94 and the main body 92 was secured by interposing the ring 98, sufficient watertightness could not be maintained by this alone.

Therefore, in the intermittent sheath 90 shown in FIG. 9, an O-ring 99 is provided on the outer peripheral surface 95 of the valve 94 pressed against the tapered portion 103 on the inner surface of the main body 92. Thereby, the water tightness between the valve 94 and the main body 92 is improved, and the rotation of the valve 94 is smooth.

[0032]

As described above, in the endoscope of the present invention, the cross-sectional shape of the inner tube is such that at least a part of the objective optical system can protrude from the side of the optical tube and the objective optical system protrudes. Since the optical tube to be formed has a different shape other than a circular shape through which the optical tube can be freely moved, the degree of freedom in the design of the objective optical system is increased, and an optimal design for obtaining desired optical performance becomes possible. In addition, since the optical tube incorporating the objective optical system can be inserted into the inner tube or removed from the inner tube, repair due to breakage of the objective optical system can be easily performed. In particular,
It becomes very easy to design the objective optical system for the side view or the back view.

[Brief description of the drawings]

1A is a side sectional view of a distal end portion of an endoscope showing one embodiment of the present invention, FIG. 1B is a sectional view taken along line AA of FIG. 1A, and FIG. It is an overall view of a mirror.

FIG. 2 is a configuration diagram of an objective optical system incorporated in an optical tube of the endoscope in FIG. 1;

FIG. 3 is a configuration diagram showing another example of a rear-view objective optical system.

FIG. 4A is an overall view of an endoscope in which an insertion portion is formed on a satin finish, and FIG. 4B is an enlarged view of the surface of the insertion portion in FIG.

5 is an enlarged view of the vicinity of the surface of the endoscope insertion portion of FIG. 4 inserted into a living body with a lubricant applied.

6 is an enlarged view of the vicinity of the surface of the endoscope insertion portion of FIG. 4 inserted into a living body without applying a lubricant.

FIG. 7A is a perspective view of a resect sheath, and FIG. 7B is a cross-sectional view of the distal end of the resect sheath of FIG.

FIG. 8 is a sectional view of a distal end portion of a conventional resect sheath.

9A is a side sectional view of an intermittent sheath, and FIG. 9B is a perspective view of a switching valve.

FIG. 10 is a side sectional view of a conventional intermittent sheath.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Endoscope, 2 ... Outer tube, 3 ... Insertion part, 4 ... Inner tube, 6 ... Optical tube, 20 ... Objective optical system.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-58-190914 (JP, A) JP-A-58-190915 (JP, A) JP-A-3-276115 (JP, A) JP-A-3-190 273207 (JP, A) Japanese Utility Model 1983-166614 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02B 23/26 A61B 1/00 300

Claims (1)

(57) [Claims] 1. An endoscope having an insertion section through which an optical tube incorporating an objective optical system is inserted into the inner tube of an insertion section main body consisting of an outer tube and an inner tube, wherein the inner tube has a cross-sectional shape. ,
At least a part of the objective optical system can be projected from a side of the optical tube, and the objective optical system has a different shape other than a circular shape into which the projected optical tube can be inserted and retracted. Endoscope.