JPH05307146A - Endoscope - Google Patents

Abstract

PURPOSE:To provide the endoscope which has the good repairable property of an objective optical system and has a degree of freedom in designing the objective optical system and with which the desired optical performance is sufficiently obtainable. CONSTITUTION:This endoscope 1 has an insertion part 3 constituted by inserting an optical pipe 6 in which the objective optical system 20 is built into an inside pipe 4 of the insertion part body consisting of an outside pipe 2 and the inside pipe 4. The sectional shape of the inside pipe 4 is formed into an irregular shape exclusive of a circular shape, in such a manner that at least a part of the objective optical system 20 can project from the lateral side of the optical pipe 6 and the optical pipe 6 projected with the objective optical system 20 can be freely retreatably inserted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope provided with an insertion portion formed by inserting an optical tube having an objective optical system into the inner tube of an insertion tube main body composed of an outer tube and an inner tube.

[0002]

2. Description of the Related Art Conventionally, endoscopes having various structures have been known. Of these, the actual application Sho 57-6465
The insertion portion of the endoscope shown in Japanese Patent Publication No. 3 or 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 section main body composed of an outer tube and an inner tube. ..

An illumination optical system is integrally fixed to the outer tube and the inner tube in the gap between the outer tube and the inner tube of the insertion portion of the triple tube structure. There is. Then, the optical tube is inserted and fixed from the proximal side into the inner tube.

Further, since the optical tube can be removed from the inner tube if necessary, for example, when the lens of the objective optical system in the optical tube is damaged, it is damaged by extracting the optical tube from the inner tube. The lens can be repaired.

[0005]

By the way, since the cross section of the inner tube has been circular (true circle) in the past, an optical tube inserted into the inner tube and an objective optical system arranged in the optical tube. Had to be designed for insertion into this circular shaped inner tube. In this case, there is a problem that the desired optical performance cannot be sufficiently obtained due to large restrictions on the design of the objective optical system. This problem was particularly serious for side-viewing and rear-viewing endoscopes in which the objective lens is arranged in a special state.

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

[0007]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides an insertion method in which an optical tube incorporating an objective optical system is inserted into the inner tube of an insertion section body composed of an outer tube and an inner tube. In an endoscope including a section, the cross-sectional shape of the inner tube,
At least a part of the objective optical system can be projected from the side of the optical tube, and the optical tube projecting from the objective optical system can be inserted into the optical tube so that the optical tube has a different shape other than a circular shape.

[0008]

Since at least a part of the objective optical system can be projected 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 circular shape into which the optical tube from which the objective optical system projects can be inserted so as to be able to advance and retreat, the objective portion can be formed without increasing the outer diameter of 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 according to the present embodiment.
Is composed of an insertion portion 3 and a main body portion 9. The main body portion 9 is provided with an eyepiece portion 42 through which the insertion portion 3 is inserted, for example, the state of the inside of the body can be observed, and a light guide 40 connected to a light source device (not shown) is connected.

As shown in FIG. 1A, the insertion portion 3 is
An outer tube 2 having a perfect circular cross section and an inner tube 4 having an elliptical cross section constitute an insertion portion main body, and an optical tube 6 incorporating an objective optical system 20 is inserted into the inner tube 4. It is fixed. The optical tube 6 can be moved back and forth 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 front end opening of the outer tube 2 is fixed to the front end of the outer tube 2 by a method such as soldering, silver brazing, welding or bonding. In addition, the tip end of the outer tube 2 is a notch portion 5 which is notched so as to open laterally
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 on a stepped portion having an opening surface parallel to the axial direction of the outer tube 2.

On the outer peripheral surface of the tip of the inner tube 4 inserted through the outer tube 2, a second closed member 14 having a cylindrical shape with a bottom for closing the tip opening of the inner tube 4 is fitted by soldering or the like. ing. The second closing member 14 is arranged at a constant distance from the first closing member 8 in the distal end portion of the outer tube 2 where the cutout portion 5 is located, and the outer surface of the base end portion of the second closing member 14 of the outer tube 2 is disposed. Notch 5
By fixing to the inner surface on the side, the fixing means for the outer tube 2 and the inner tube 4 on the tip side of the insertion portion 3 is formed.

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

Further, in the gap between the outer pipe 2 and the inner pipe 4,
The light guide fiber 10 connected to the light source device via the light guide 40 is loaded. The light guide fiber 10 is provided in the gap between the outer tube 2 and the second closing member 14 and the 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 illumination light can be emitted to the outside through the opening of the cutout 5. The light guide fiber 10 is integrally fixed to the outer tube and the inner tube.

Further, an optical tube 6 inserted through the inner tube 4 is arranged.
As shown in FIG. 2, the objective optical system 20 incorporated therein is composed of a lens 26, a prism 24, and a front lens 22. The lens 26 at the rear end is fitted to the inner surface of the front end portion 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 projects laterally of the optical tube 6 with its entrance surface facing rearward 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 the object light incident on the front lens 22 through the cover lens is reflected once by the reflecting surface 23 of the prism 24, and the objective optical system 20 is provided behind the objective optical system 20. It is transmitted to the relay system and the eyepiece system placed at. 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 for observation.

By the way, the optical tube 6 in which a part of the objective optical system 20 (the front lens 22 in the case of this embodiment) is projected from the side should be inserted into the inner tube 4 having a circular cross section. I can't. However, 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 for reducing the diameter of the insertion portion 3.

However, in the case of the endoscope 1 of this embodiment, the inner tube 4 is capable of advancing and retracting the optical tube 6 from which the objective optical system 20 projects from the side while maintaining the thinning of the endoscope 1. Its cross-sectional shape is elliptical over its entire length so that it can be inserted (see FIG. 1B). That is, by making the inner tube 4 an elliptical shape that is long in the radial direction in which the front lens 22 projects, the optical tube 6 moves back and forth within the inner tube 4 without increasing the outer diameter of the insertion portion 3, that is, the outer tube 2. It is possible to secure free movement.

As described above, the endoscope 1 of this embodiment
Is a cross-sectional shape of the inner tube 4 other than a circular shape in which at least a part of the objective optical system 20 can project from the side of the optical tube 6 and the optical tube 6 from which the objective optical system 20 projects can be inserted in a retractable manner. Due to the different shape, 1. The degree of freedom in designing the objective optical system 20 is increased, and the optimum design for obtaining desired optical performance is possible.

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

The cross-sectional shape of the inner tube 4 is not limited to an elliptical shape, but may be any shape other than a perfect circle, such as a rice ball shape, a triangle, or a quadrangle.
It may be appropriately selected according to the aspect of the objective optical system 20 protruding from the optical tube 6. Further, the objective optical system 20 is not limited to the lens system, and may be an image fiber, CCD or the like.

By the way, as is the case with this embodiment, the 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 rear-viewing objective optical system 50 shown in FIG. 3 is also an example. The objective optical system 50 is composed of a lens 56, a prism 54, and a front lens 52, and the object light incident on the front lens 52 is reflected by the reflecting surfaces 51 and 53 of the prism 54 and the reflecting surface 55 of the lens 56.
Is reflected three times in total. In the endoscope 50 shown in FIG. 4, the outer surface of the insertion portion 66 is finished in a satin finish. That is, although the outer surface of the insertion portion 66 is enlarged in FIG. 4B, as shown in the figure, the concave portion 66a and the convex portion 66b are continuously formed in a satin-like shape on the outer surface of the insertion portion 66. Has been formed. The insertion portion 66 may be a nickel-white pipe plated with chrome, an unplated pipe, or a gold-plated stainless pipe.

As described above, by making the surface of the insertion portion 66 satin, the lubricant 68 is applied when the surface of the insertion portion 66 is coated with the lubricant 68 (see (1) of FIG. 4).
Is uniformly inserted regardless of the unevenness of the surface of the insertion portion 66.
When the insertion part 66 is inserted into the patient's body while covering the surface of the insertion part 6 (see FIG. 5), even if the internal tissue 70 is in close contact with the surface of the insertion part 66, the lubricant 68 is at least a concave part on the surface of the insertion part 66. The lubricant 68 remaining in the body 66a and remaining in the recess 66a along with the insertion of the insertion portion 66 into the body gradually flows out between the projection 66b and the tissue 70, so that the tissue 70 and the surface of the insertion portion 66 are separated from each other. The frictional resistance between them decreases continuously.

When the lubricant 68 is not used (see FIG. 6)
However, since the surface of the insertion portion 66 is uneven, the internal tissue 70 only contacts the projection 66b on the surface of the insertion portion 66. Therefore, as compared with the case where the surface of the insertion portion 66 is smooth, the contact area between the insertion portion 66, the surface, and the tissue 70 is smaller. Therefore, the frictional resistance when the insertion section 66 is inserted into the body of the patient becomes small, and it becomes easy to insert the insertion section 66 into the body.

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

Conventionally, the distal end portion 82a of the mandolin 82 protruding from the distal end 84a of the insertion portion 86 is formed into a cannonball shape as shown in FIG. 8, so that the distal end portion 82a can be inserted into a flexible living body duct such as the urethra. I didn't like it. That is, the distal end portion 82a of the mandolin 82 was caught at the bent portion of the living body conduit and could not be successfully inserted into the living body conduit.

In order to solve such a problem, the reject sheath 80 shown in FIG. 7 has an oblique cut shape having an outward bulge in a state in which the distal end portion 82a of the mandolin is substantially along the oblique shape of the opening edge of the distal end 84a of the insertion portion 86. It was formed in. With this, when the retract sheath 80 is inserted into, for example, the urethra, the tapered portion 85 of the distal end portion 82a of the mandolin 82 passes through the bent portion of the urethra along the bent surface, so that the distal end portion 82a of the mandolin 82 is inserted into the urethra. It is possible to avoid a situation in which the bent portion of the item is caught.

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

As shown in FIG. 9B, an outer peripheral surface 95 of the switching valve 94 is formed in a tapered shape, and the switching valve 94 is operated by operating the lever 102.
When it is rotated within 2, the communication hole 101 provided on the outer peripheral surface 95 of the valve 94 becomes the water supply mouthpiece 93 or the drainage mouthpiece 10.
It corresponds to any one of the 0 inner holes.

Conventionally, as shown in FIG. 10, the tip of the mouthpiece member 97 is pressed against the rear end of the valve 94 while the mouthpiece member 97 is fastened to the main body portion 92 by the tightening member 96, and the tapered valve outer peripheral surface 95 is formed. The pressure is applied to the corresponding tapered portion 103 on the inner surface of the main body portion 92, and O is provided between the mouthpiece member 97 and the rear end of the valve 94 which is pressed against this.
Although water tightness was secured between the valve 94 and the main body 92 by interposing the ring 98, sufficient water tightness could not be maintained only by this.

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. As a result, the watertightness between the valve 94 and the main body 92 is improved, and the valve 94 rotates smoothly.

[0032]

As described above, according to 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 project from the side of the optical tube and the objective optical system projects. By making the optical tube to be inserted into a different shape other than the circular shape so that the optical tube can be inserted and removed freely, the degree of freedom in the design of the objective optical system is increased, and the optimum design for obtaining the desired optical performance becomes possible. In addition, since the optical tube incorporating the objective optical system can be inserted into or removed from the inner tube, the objective optical system can be easily repaired due to damage or the like. In particular,
It is very easy to design an objective optical system for side-viewing or rear-viewing.

[Brief description of drawings]

1A is a side sectional view of a distal end portion of an endoscope showing an 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.

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

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

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

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

FIG. 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 detect sheath, and FIG. 7B is a cross-sectional view of a tip portion of the detect sheath of FIG.

FIG. 8 is a cross-sectional view of a tip portion of a conventional detect 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 ... Insert part, 4 ... Inner tube, 6 ... Optical tube, 20 ... Objective optical system.

Claims (1)

[Claims] 1. An endoscope having an insertion portion formed by inserting an optical tube having an objective optical system into the inner tube of an insertion section main body composed of an outer tube and an inner tube, wherein a cross-sectional shape of the inner tube is ,
At least a part of the objective optical system can be projected from the side of the optical tube, and the optical tube from which the objective optical system projects is formed into a different shape other than a circular shape so that the optical tube can be inserted in a retractable manner. Endoscope.