JPH0143684Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rigid endoscope that has been improved so that an inner tube housing an observation optical system and a light guide fiber can be easily inserted into an outer tube.

In recent years, by inserting a long and thin insertion section into a body cavity, organs within the body cavity can be observed, and if necessary, in-vivo tissues can be collected using forceps inserted through the forceps channel to diagnose the affected area in detail. Medical endoscopes are widely used.
Furthermore, in the industrial field, endoscopes are also used for maintenance purposes, such as observing the condition inside pipes of boilers, chemical plants, etc., or collecting and inspecting deposits on the inner surfaces of pipes.

The above endoscope is a flexible endoscope with a flexible insertion part,
The insertion section is roughly divided into rigid endoscopes, which have a rigid insertion section.In the case of the latter, a relay optical system (relay lens system) with excellent resolution is used as an image transmission means inserted through the insertion section. It is used.

1 to 3 illustrate a conventional medical perspective rigid endoscope.

1 is a longitudinal sectional view of the rigid endoscope, FIG. 2 is a side view of the distal end of the inner tube in FIG. 1, and FIG. 3 is a view of FIG. 2 viewed from the direction of the arrow.

This type of rigid endoscope includes an insertion section 1 that is inserted into a body cavity, and this insertion section 1 has an operation section 2 on the proximal side.
It is designed to be installed in This operation section 2
An eyepiece section 3 is provided at the rear of the camera.

An outer tube 1a is disposed at the outermost side of the insertion portion 1, and an inner tube 1b is installed eccentrically inside the outer tube 1a, and a lens tube 1c is coaxially arranged inside the inner tube 1b. Decorated. An observation optical system 4 for visually checking the inside of the body cavity is housed inside this lens tube 1c.

On the other hand, a light guide fiber 5 is installed between the inner tube 1b and the outer tube 1a. The rear end of the light guide fiber 5 is connected to a light guide cable via a light guide cap 6 provided on the side of the operating section 2. The light guide cable is optically connected to an external light source, and illumination light from the external light source is supplied into the body cavity by the light guide cable and the light guide fiber 5 and passes through the body cavity. It is designed to illuminate.

The observation optical system 4 includes an objective lens system 4a that is housed in the distal end of the insertion section 1 and forms an image of an object in the body cavity, a relay lens system 4b that transmits this image to the operator side, and It is composed of an eyepiece system (not shown) that adjusts, such as enlarging, the image transmitted by the relay lens system 4b.

Thus, the outer tube 1a is fitted into the front part of the operating section main body 2a, while the rear part of the inner tube 1b is designed to fit into the inner tube provided midway in the axial direction of the operating section main body 2a. It is adapted to be tightly fitted and fixed into the opening 2b. On the other hand, the inner tube 1
As shown in FIG. 3, a pressing member 7 for pressing the light guide fiber 5 against the inner circumferential surface of the mantle tube 1a and regulating its arrangement position is attached to the tip of the light guide fiber 5b.

Therefore, even if an attempt is made to insert the inner tube 1b into the insertion section 1 from the rear of the endoscope itself, that is, from the eyepiece section 3 side through the inner tube opening 2b, the inner tube 1b
Since the pressing member 7 attached to the distal end of the inner tube hits the inner tube opening 2b, it is impossible to insert the inner tube 1b into the insertion section 1 from the eyepiece section 3 side. Ta.

For this reason, conventionally, the inner tube 1b has been inserted from the distal end side of the insertion section 1 with the inner tube 1b facing backward. However, in this case, in order to insert the light guide fiber 5 into the insertion section 1, the inner tube 1b is first pulled down to the rear as shown in FIG. The tip of the light guide fiber 5 is inserted into the insertion portion 1 by an appropriate length through the drilled opening 6a. Thereafter, the inner tube 1b is pushed into the insertion section 1 to the front side, and at the same time, the light guide fiber 5 is dragged by the distal end surface of the inner tube 1b and pushed into the insertion section 1.
Interior decoration required a lot of troublesome work.

In addition, after use, endoscopes are generally subjected to high-pressure steam sterilization or dry heat sterilization, but if the endoscope is exposed to such high temperatures, Although it would be possible to expand at a uniform rate of expansion all the way to the top, there is a difference in thermal expansion between the surface side, which is directly affected by temperature, and the inside side, which is indirectly affected by temperature. Distortion is unavoidably generated between the inner side and the inner side. For this reason, there was a problem that such distortion occurred between the outer tube 1a and the inner tube 1b.

West German Utility Model Registration No. 7520162 has been disclosed as a solution to the problem caused by the difference in thermal expansion.

In this prior art, an insertion section inserted into a body cavity is attached to an operating section, and an eyepiece section is disposed behind the operating section. An inner tube housing an observation optical system is inserted and disposed within this insertion portion. This inner tube is slidably inserted into an inner tube insertion path provided in the direction of the central axis of the operating section main body with a gap provided therebetween. This inner tube extends from the distal end of the insertion section through the inner tube insertion path of the operating section to the eyepiece section, thereby allowing the operator to visually check the inside of the body cavity. However, in the case of this prior art, a stretchable bellows-like thin film is used to solve the problem caused by the above-mentioned difference in thermal expansion. This bellows-like thin film is
It is formed into a substantially funnel shape with a small diameter opening at one end and a large diameter opening at the other end, and the vertical cross section of the side surface is formed into a bellows shape. Then, the inner tube is inserted through this approximately funnel-shaped thin film with the small diameter opening end of the thin film facing forward and the large diameter opening end facing the rear, and then the small diameter opening end is placed around the outer periphery of the inner tube. The large diameter opening end is fixed to the rear opening end of the inner tube insertion path of the operating section. With this configuration, a thin film is stretched between the outer circumference of the inner tube and the opening end of the inner tube insertion path of the operation section main body. In this way, when distortion occurs between the inner tube and the operating section due to the difference in thermal expansion, and the inner tube relatively expands and contracts, this expansion and contraction is caused by the expansion and contraction of the bellows-like thin film. This structure absorbs the expansion and contraction movement of the inner tube, thereby creating a liquid-tight relationship between the inner tube and the main body of the operating section.

However, in the case of this prior art, since the seal between the inner tube and the main body of the operating section is achieved by a thin film, there is a problem that this thin film is easily damaged, or the thin film itself is broken into small pieces. There was a problem in that it was difficult to manufacture this thin film due to the barrier structure formed in the film. Furthermore, in this case, the thin film had to be attached to the inner tube and the main body in a liquid-tight manner, making the attachment work difficult.

The present invention was developed in view of the above circumstances, and it not only makes it extremely easy to insert and attach the inner tube and light guide fiber into the outer tube when assembling a rigid endoscope, but also enables high-pressure steam sterilization or drying. Rigidity that prevents damage to the endoscope by eliminating distortion caused by the difference in thermal expansion between the surface and the inside, even when exposed to high temperatures for purposes such as heat sterilization. It provides endoscopes.

In order to achieve the above object, the present invention includes an insertion section,
The insertion section is equipped with an operating section, an inner tube is inserted into the outer tube constituting the insertion section, and a light guide is provided between the inner circumferential surface of the outer tube and the outer circumferential surface of the inner tube in the axial direction of the insertion section. While the fiber is installed inside the inner tube, a pressing member is provided at the tip of the inner tube to regulate the position of the light guide fiber tip, and an opening for inserting the inner tube is formed in the axial direction of the operating section. In a rigid endoscope in which a liquid-tight seal is formed between the inner tube inserted into the tube insertion opening and the operating section, the insertion opening at the rear of the operating section is
A connecting member is removably attached to the rear of the operating part, which has an enlarged diameter opening so that the pressing member provided at the tip of the inner tube can be inserted therethrough, and has a through hole for inserting the inner tube through which the inner tube is inserted. , is characterized in that an O-ring is disposed between the connecting member and the rear outer periphery of the inner tube to ensure liquid tightness.

The present invention will be explained in detail below with reference to the drawings.

5 to 7 relate to the first embodiment, and FIG.
The figure shows a perspective type rigid endoscope of the first embodiment, FIG. 6 shows an exploded view of the configuration of FIG. 5, and FIG. 7 shows the objective and relay optical system which are the main parts of the first embodiment. Parts are shown enlarged.

In these figures, the rigid endoscope 11 of the first embodiment has an elongated insertion section 12 inserted into a body cavity.
and an operating section 13 formed at the rear end of the insertion section 12.
and an eyepiece section 1 formed on the rear end side of the operation section 13.
Consists of 4.

The insertion portion 12 is covered with a hard pipe-shaped outer tube (mantle tube) 15, and the rear end of the outer tube 15 is provided with a light guide cap 16 on the side to which a light guide cable (not shown) is attached. It is fixed to the inner circumferential surface of the open front end of the portion 13 by brazing or the like.

An inner tube insertion opening 13a into which an inner tube 20 (to be described later) is inserted is formed in the central axis direction of the operation section 13, and a front end is formed on the inner peripheral surface of the rear end of the operation section 13. A connecting member 17 whose side outer peripheral surface can be attached and detached by screwing is connected, and a watertight O-ring 18 is disposed in a recess formed on the outer periphery of this connecting member 17, and a screw is attached to the rear end side outer periphery adjacent to this recess. It is covered with an outer cylinder 19 (eyepiece part) in which a groove is formed, the inner circumferential surface on the front end side contacts the O-ring 18, and a screw hole is formed to be screwed into the groove.

On the other hand, inside the outer tube 15, an inner tube 20 serving as an optical system storage tube is provided in contact with the upper inner circumferential surface of the outer tube 15.
is arranged, and the rear end side of this inner tube 20 is provided with an operating section 13
It extends further rearward and is fitted and fixed to the inner circumferential surface of a small-diameter through hole that fits into the outer diameter of the inner tube 20 of the connecting member 17 . A light guide fiber, which will be described later, is connected to the outer circumference of the outer tube 15 on the upper side of the outer circumference of the tip of the inner tube 20.
A pressing member 28 is attached to press against the inner circumferential surface of the light guide fiber to regulate the position of the distal end of the light guide fiber. In fixing using the connecting member 17, the diameter of the front end of the through hole that fits into the outer diameter of the inner tube 20 is expanded, an O-ring 21 is housed inside, and a retaining ring 22 having a thread formed on the outer periphery is used to secure the O-ring 21. The structure is such that not only liquid but also gas such as water vapor does not enter the rear side of the inner tube 20 (or the connecting member 17) at the portion that is in close contact with the outer periphery of the inner tube 20 by sandwiching the O-ring 21 therebetween. The outer circumference of the distal end of the inner tube 20 is fixed to the inner circumference of the distal end of the mantle tube 15, whereas the rear side of the inner tube 20 is not fixed to the inner circumference of the mantle tube 15, as described above. O-ring 2
1 only provides liquid tightness between the connecting member 17 and the inner tube 20. Therefore, when the endoscope is exposed to high temperature for the purpose of high-pressure steam sterilization or dry heat sterilization, for example, the above-mentioned jacket The difference in thermal expansion that occurs between the tube 15 and the inner tube 20 is due to the difference in thermal expansion between the inner tube 20 and the outer tube 1.
It is absorbed by freely expanding and contracting with respect to 5.

A hemisphere is obliquely cut out on the distal end side of the outer tube 15 to form a perspective opening for observation and illumination, and a cover glass mounting frame 23 is fixed to the distal end of the inner tube 20 facing the opening. The fixing frame 24 is press-fitted into this cover glass mounting frame 23 to attach the cover glass 2.
5 is clamped and installed so as to maintain airtightness and liquidtightness.

On the other hand, a light guide fiber 26 is inserted into a gap having a substantially crescent-shaped cross section between the eccentrically arranged outer circumference of the inner tube 20 and the inner circumference of the outer tube 15 so as to transmit the illumination light and emit it from the end surface. , this rear end side is curved at a substantially right angle in the operation part 13 and fixed with a light guide base 16, and the illumination light supplied from a light source device (not shown) via a light guide cable is attached to the tip of the inner tube 20. Light is emitted from the end face of the light guide fiber 26, which is curved along the outer periphery of the cover glass mounting frame 23 and the inner periphery of the hemispherical cutout of the tip of the outer tube 15, and illuminates the object in front in the oblique direction. It is configured as follows.

By the way, inside the inner tube 20, as shown in FIG. 6 or 7, there is a cylindrical objective relay (optical system).
It is configured to be inserted by fitting the storage tube 27 therethrough.

A front objective lens frame 29 is fixed to the front end of the objective relay housing tube 27 by adhesive or the like, and a front objective lens 30 is fixed to the peripheral edge that contacts the front objective lens frame 29 by adhesive or the like. There is. This objective front lens 3
The front end surface of an objective prism 31 is in contact with and fixed to the rear end surface of the objective front lens frame 29, which is fixed to the front end side. fixed so that they touch each other.

Behind the objective lens 32 is the objective lens 3.
A rear objective lens 34 is fixed to the objective relay storage tube 27 via an objective middle frame 33 to which the objective relay housing tube 27 is fixed. A spacer 35 having a predetermined length is mounted on the rear surface of the rear objective lens.

A relay rod lens serving as an image transmission means is arranged such that the front peripheral edge is in contact with the spacer ring 35, and a spacer ring (hereinafter the same reference numeral 36) having each predetermined length is also in contact with the rear face. 37, a relay cemented lens 38 and the like are fixed at predetermined intervals, and in the illustration, a relay rod lens 37' is partially protruded from the rear end of the objective relay housing tube 27.
is fixed with adhesive, etc.

Relay rod lens 3 behind the objective optical system above.
7. The objective relay housing tube 27 housing the relay optical system such as the relay cemented lens 38 is inserted into the inner tube 20 and fixed at a predetermined position, and the relay rod disposed at the rear of this relay optical system is inserted into the inner tube 20 and fixed at a predetermined position. lens 37'
At the rear, the front end side is fitted into the rear end side of an eyepiece adjustment tube 40 which is fixed with a screw 39 to the inner periphery of the enlarged diameter rear end of the connecting member 17, and an eyepiece lens system 41 is attached to the rear end thereof. An eyepiece frame 42 is fixed with a screw 43, and a recess is formed at the front end side of the eyepiece frame 42 to accommodate a field stop 44.

Further, the eyepiece system 41 is fitted and accommodated in an open end with a slightly enlarged diameter at the rear end of the eyepiece frame 42, and a fixed frame 45 has a protruding edge that abuts against the peripheral edge of the rear end of the eyepiece frame 41. The eyepiece lens system 41 is fixed by screwing it onto the outer periphery of the eyepiece frame 42.

A (eyepiece) cover glass 4 is provided in the opening at the rear end of the outer tube 19 of the eyepiece section 14 that houses these eyepiece optical systems.
6 connects the front end side of the cover glass fixing frame 47 to the outer cylinder 1.
By press-fitting into the outer periphery of the narrowed rear end of the cover glass 45, the tapered portion of the rear end periphery of the cover glass 45 is pressed forward and fixed. An eyepiece 48 is screwed from the rear end side of the outer periphery of the outer cylinder 19 to which a cover glass fixing frame 47 is attached.

In the first embodiment configured in this way,
As shown in FIG. 8, the distal end of the inner tube 20 is slightly inserted into the operating section 13 through the enlarged-diameter inner tube insertion opening 13a that is largely opened at the rear end of the operating section 13. . Further, from the opening provided in the operation section 13 to which the light guide cap 16 is attached,
Insert the tip of the light guide fiber 26 slightly. Thereafter, while pushing the inner tube 20 into the insertion section 12, the light guide fiber 26 is inserted into the insertion section 12 with the lower surface of the distal end of the inner tube 20.
Insert it by dragging it inward. At this time, the inner tube insertion opening 13a of the operating section 13
Since the rear end is formed with a large enlarged diameter, the inner tube 20 can be freely vibrated up and down, left and right, and while vibrating the inner tube 20, the light guide fiber 26 can be damaged. It can be pushed into the insertion section 12 smoothly and without strain.

In this manner, after the inner tube 20 and light guide fiber 26 have been pushed into the insertion section 12, the connecting member 17 is screwed onto the operating section 13 from the rear side to support the rear portion of the inner tube 20. First, an O-ring 21 is attached to the front of the connecting member 17 in the recess of the connecting member 17, and the O-ring 21 is attached to the front of the connecting member 17. Attach a presser ring 22 that clamps and presses against. Due to the presence of this O-ring 21, liquid tightness between the inner tube 20 and the connecting member 17 is maintained.

Further, according to the first embodiment, the objective optical system and the relay optical system are installed, and after sufficient adjustment, the inner tube 20
can be inserted into the body and secured in place. Further, in the case of a perspective view type, setting the viewing direction to a predetermined direction can be easily done by rotating the objective relay housing tube 27 at the hand side.

As described above, according to the first embodiment, it is possible to easily assemble and adjust the inner tube 20 and the light guide fiber 26, which are attached to the tip end of the pressing member 28 that regulates the arrangement position of the light guide fiber. Furthermore, there is no risk of damaging the inner tube, the light guide fiber, and surrounding members during these operations.

9 to 11 relate to the second embodiment, and FIG. 9 shows a perspective type rigid endoscope of the second embodiment,
FIG. 10 shows an exploded view of the second embodiment, and FIG. 11 shows an observation optical system according to the second embodiment.

In these figures, the rigid endoscope 51 of the second embodiment is configured such that an eyepiece optical system can be further integrated with the rear end of the objective relay storage tube 27 in the first embodiment by screwing.

That is, in the second embodiment, like the first embodiment, a connecting member 17' is attached to the rear end of the inner tube 20' so that the O-ring 21 is kept liquid-tight by a retaining ring 22. Similar to the first embodiment, this connecting member 17' accommodates the O-ring 18 inside the eyepiece portion 1.
It is configured to be covered with four outer cylinders 19.

In this embodiment, the eyepiece adjusting barrel 40' to which the front end side of the eyepiece frame 42 is fixed is not attached to the rear end side of the connecting member 17' as in the first embodiment, but is attached to the objective through an intermediate barrel 52. Relay storage pipe 27
It is attached to the rear end.

The intermediate cylindrical body 52 has an inner diameter that fits on the outer periphery of the objective relay housing tube 27, and has a diameter enlarged at the rear end side and a threaded portion formed on the inner circumferential surface, into which it is screwed. Ring-shaped fixed frame 53 with screws formed on the outer periphery
is accommodated. A projecting edge portion projecting inward is formed on the rear end side of the fixed frame 53, and the relay rod lens 37' is fixed by this projecting edge portion so as to be pressed forward.

Furthermore, a threaded portion is formed on the outer periphery of the rear end side of the intermediate cylinder 52, and the threaded portion is screwed into a screw hole formed on the inner periphery of the eyepiece adjustment cylinder 40'.
0' is attached.

In this way, the objective optical system is housed on the front end side of the objective relay housing tube 27 as in the first embodiment, and furthermore, in this embodiment, the objective relay housing tube 27
An eyepiece frame 42 can be integrally attached to the rear end side via an intervening member. This integrated observation optical system 54 is inserted into the inner tube 20' after adjustment,
Connecting member 1
7'. The other parts are the same as those in the first embodiment, and the same elements are given the same reference numerals.

In the second embodiment, after the objective relay housing tube 27 in which the objective optical system and relay optics are housed in the first embodiment is inserted into the integrated insertion section 12 and operation section 13 as shown in FIG. The first eyepiece optical system is
As shown in FIG. 0, the eyepiece optical system is also integrated before assembly to form the observation optical system 54 shown in FIG. 11, making adjustment easier.

In the first and second embodiments, strabismus-type rigid endoscopes 11 and 51 are shown, but the present invention is of course not limited to this, and can be similarly applied to direct-viewing and side-viewing types. It can be applied to

The above-mentioned means for integrating the optical system may be made removable by mechanical connection means such as press-fitting or screwing, or may be connected and fixed by adhesive, soldering, brazing, etc.

Further, FIG. 12 shows a third embodiment of the present invention. In the above embodiment, the diameter of the through hole for inserting the inner tube of the connecting member 17 is set to the outer diameter of the inner tube 20, that is, the diameter of the O-ring 2.
Since the O-ring 21 is formed to match the inner diameter of the connecting member 17, when screwing the connecting member 17 onto the operating section 13, the O-ring 21 must first be attached to the front part of the connecting member 17. In the case of the embodiment, the inner tube insertion through hole 61 formed in the connecting member 61
The inner diameter of a is slightly larger than the outer diameter of the O-ring 62, and a separate retainer ring 63 is installed behind the O-ring 62, so that The connecting member 61 is screwed onto the rear part of the operating section, and then this connecting member 6
1, the O-ring 62 is pushed in from the rear of the insertion section, and the outer circumferential surface of the inner tube that has already been inserted into the insertion section is slid over and advanced to the desired position. At the time of screwing, the O-ring 62 is not yet attached to the connecting member 61, which has the advantage that the operation of attaching the connecting member 61 is easy to perform.

As explained above, according to the present invention, the inner tube insertion opening formed in the operating section is opened to an enlarged diameter at the rear of the operating section, and at the rear of the operating section,
A connecting member having a through hole for inserting the inner tube through which the inner tube is inserted is removably attached, and an O-ring is placed between this connecting member and the rear part of the inner tube to ensure liquid tightness. When assembling the endoscope, the enlarged-diameter inner tube insertion opening formed at the rear of the operating section can be exposed, making it extremely easy to insert the inner tube and the light guide fiber, which have a pressing member at their tip. It can be inserted into the outer tube and installed internally.

In addition, in this invention, the inner tube is configured to be able to expand and contract in the axial direction, so even when the endoscope is exposed to high temperatures for the purpose of high-pressure steam sterilization or dry heat sterilization, the inner tube remains It is possible to sufficiently absorb the distortion caused by the difference in thermal expansion between the two.

[Brief explanation of the drawing]

1 to 4 show a conventional endoscope, and FIG. 1 is a vertical sectional view of the conventional endoscope, and
The figure is a side view of the tip of the inner tube, Figure 3 is a front view of Figure 2, Figure 4 is a longitudinal sectional view when inserting the inner tube and light guide fiber into the outer tube, and Figures 5 to 7. The figures show the first embodiment of the present invention, and FIG. 5 is a longitudinal cross-sectional view of a perspective type rigid endoscope, and FIGS.
The figure is a schematic side view for explaining the exploded configuration of FIG. 5, FIG. 8 is a longitudinal sectional view when inserting the inner tube and light guide fiber into the outer tube, and FIGS. 9 to 11 are the main body tubes. A second embodiment of the invention is shown, and FIG. 9 is a longitudinal cross-sectional view of the rigid endoscope, and FIGS.
The figure is a schematic side view for explaining the exploded structure of FIG. 9, and FIG. 12 is a longitudinal cross-sectional view of the vicinity of the connecting member showing a third embodiment of the present invention. 12...insertion section, 13...operation section, 13a...
Inner tube insertion opening, 15... outer tube, 17... connecting member, 20... inner tube, 21... O-ring, 26...
...Light guide fiber, 28...Press member.

Claims (1)

[Scope of utility model registration request] It comprises an insertion section and an operating section to which the insertion section is attached, an inner tube is inserted into the outer tube constituting the insertion section, and an insertion section axis is inserted between the inner circumferential surface of the outer tube and the outer circumferential surface of the inner tube. A light guide fiber is installed inside the light guide fiber in the direction, while a pressing member is provided at the tip of the inner tube to regulate the arrangement position of the tip of the light guide fiber, and an opening for inserting the inner tube is formed in the axial direction of the operating part. At the same time, in a rigid endoscope in which a liquid-tight seal is formed between the inner tube inserted into the inner tube insertion opening and the operating section, a pressing member presses the insertion opening at the rear of the operating section. A connecting member is removably attached to the rear of the operation part, the opening is enlarged in diameter so that the distal end of the provided inner tube can be inserted therethrough, and the through hole for inserting the inner tube through which the inner tube is inserted. A rigid endoscope characterized in that an O-ring is disposed between the member and the rear outer periphery of the inner tube to ensure liquid tightness.