JPH0434500Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an endoscope in which the structure of the optical system section in the distal end component is improved.

[Conventional technology]

Generally, an objective optical system is provided at the tip of an endoscope insertion section. (See, for example, Japanese Utility Model Application Publication No. 121844/1983).
That is, the first objective lens of this objective optical system is mounted liquid-tightly to the outside. Also,
On the other hand, an objective lens group consisting of a plurality of lenses is held in a cylindrical lens frame, but this lens frame is simply fitted into the main body of the tip component. Therefore, there is no airtightness to the inside of the endoscope insertion section.

[Problem that the invention attempts to solve]

By the way, when the insertion section of the endoscope or its entirety is repeatedly cleaned or disinfected, water vapor gradually enters from the resin outer cover of the insertion section and the curved rubber of the curved section, causing the lens of the objective optical system to deteriorate. Highly humid air fills the space. Further, the resin coating on the inner and outer surfaces of the lens frame for the purpose of blocking light becomes hydrated.

When this endoscope is inserted into a body cavity, the tip of the insertion part is rapidly warmed to a temperature close to body temperature, and the water contained in the resin coating evaporates, causing the objective object to evaporate. The area between the lenses of the optical system becomes even more humid.

However, during this endoscopy, the first objective
Since the outer surface of the lens is exposed to the body cavity,
Mucus such as gastric juice adheres, making observation difficult. To remove this dirt, water is sent through a nozzle near the observation window to wash it off.The water used for this purpose is tap water or sterilized water, but this water is generally at a temperature lower than body temperature. By this water supply operation, the temperature of the first objective lens is rapidly lowered from close to body temperature to the temperature of the supplied water, and the hot and humid air inside is also cooled. For this reason, water droplets condensed on the inner surface of the first objective lens, and the field of view seen from the eyepiece appeared to be hazy, which hindered inspection.

On the other hand, since only the first objective lens is airtightly attached to the outside, if the endoscope is used or cleaned and disinfected while the airtightness is broken due to damage or other reasons, the inside of the endoscope may become soaked with water. Repairs were costly and time consuming.

The present invention was developed in view of the above problems, and its purpose is to prevent moisture from entering from inside and outside the endoscope into the optical system of the distal end component, and to prevent moisture from entering the optical system of the distal end component, and to To provide an endoscope which can prevent dew condensation on the interior of the endoscope and prevent water, mucus, etc. from entering the entire interior of the endoscope even if the airtightness of optical members exposed to the outside is lost.

[Means and actions for solving problems]

In order to solve the above problems, the present invention provides a mounting hole for incorporating a plurality of optical members in the tip component,
In this endoscope, an optical member constituting the observation window attached to the attachment hole and an optical member located inside the attachment hole are each airtightly attached to airtightly close the space between the two optical members.

Since the above-mentioned space is airtight from the inside and outside of the endoscope, moisture does not enter this space and humidity does not increase, so that no dew condensation occurs even if the temperature drops. Furthermore, even if water or mucus enters when the airtightness of the optical member at the tip is compromised, it is blocked by the optical member at the rear and no longer enters the endoscope.

〔Example〕

1 and 2 show a first embodiment of the present invention.

FIG. 2 shows the entire endoscope 1, which includes an insertion section 2, an operation section 3, and a light guide cable 4. As shown in FIG. The insertion section 2 consists of a flexible tube 5, a curved tube 6, and a tip component 7, which are located sequentially from the operation section 3 side. It is designed to be curved. The operation unit 3 is provided with an air/water supply button 9 and a suction button 10 side by side.
Further, an eyepiece section 11 is provided at the proximal end.

Furthermore, an observation window 12, a pair of illumination windows 13, 13, a nozzle 14, and a suction port 15 are provided at the distal end of the distal end component 7, respectively. As shown in FIG. 1, the distal end component 7 includes a main body 15 and a distal end cover 16 attached thereto, and a through hole 17 that extends through the main body 15 and the distal cover 16 along the axial direction of the insertion section 2 is formed. It is perforated. This through hole 17
A cylindrical lens frame 18 is fitted into the tip of the lens frame 18,
It is airtightly fixed by adhesive. This lens frame 18 is provided with a circumferential protrusion 19 on its outer periphery, and a large diameter cylindrical part 21 on the tip side of the protrusion 19;
The rear end side of this protrusion 19 is a small diameter cylindrical portion 22 . A stepped portion 23 is formed on the inner peripheral surface between each of the cylindrical portions 21 and 22. A diaphragm 24 that abuts against the stepped portion 23 is fitted into the large-diameter cylindrical portion 21 of the lens frame 18, and a first objective, which is an optical member exposed to the outside, is attached to the tip side of the diaphragm 24. A lens 25 is fitted. Further, a second objective lens 26, which is an optical member, is fitted into the small diameter cylindrical portion 22 on the rear end side of the aperture 24. That is, the inside of the lens frame 18 constitutes a mounting hole 27 in which a plurality of optical members are arranged.

The inner diameter of the large-diameter cylindrical portion 21 into which the first objective lens 25 is fitted is formed to be slightly larger than the outer diameter of the first objective lens 25, and a cylindrical groove is formed therebetween and bonded to this groove. Airtightness with the outside is ensured by filling the agent 28 without any gaps. Furthermore, the inner diameter of the small-diameter cylindrical portion 22 into which the second objective lens 26 is fitted is also formed slightly larger than the outer diameter of the second objective lens 26, and a cylindrical groove is formed between the two and bonded to this groove. By filling the agent 29 without any gaps, airtightness is ensured between the inside and outside of the endoscope 1. Furthermore, a space 30 between the first objective lens 25 and the second objective lens 26
Since it is surrounded by the lens frame 18, it is airtightly closed. In other words, this space 30 is airtight from both the inside and outside of the endoscope 1.

On the other hand, a support tube 3 is provided at the base end portion of the through hole 17.
1 is inserted. A rear group lens 33 incorporated into the second lens frame 32 is attached within the tip of the support tube 31. In addition, the support tube 3
An image guide fiber 34 is located within the rear end of 1.
A tip cap 35 is fitted and fixed, and a lens 36 is attached to the tip surface of the image guide fiber 34 in close contact. Thus, the visual field image seen through the observation window 12 is reflected by each lens 25, 26, 3
3 and 36 to form an image on the distal end surface of the image guide fiber 34, and this formed image is transmitted to the eyepiece 11 through the image guide fiber 34,
It is designed to be observed through this eyepiece section 11.

Further, a fitting hole 37 into which the nozzle 14 is inserted is bored in the main body 15 of the tip forming portion 7. The nozzle 14 is adhesively fixed to the insertion hole 37. Furthermore, a pipe 38 is fitted into the fitting hole 37 of the main body 15 and fixed with adhesive.
is installed. Further, an air/water supply tube 39 is connected to this pipe 38. This air/water supply tube 39 is guided through the insertion section 2 to the operating section 3, where the air/water supply button 9 is connected.
By operating the nozzle 14, air and water can be selectively supplied to the nozzle 14.

Therefore, the first objective lens 25 is connected to the endoscope 1.
The second objective lens 26 is airtight to the outside of the endoscope 1, and the second objective lens 26 is airtight to the inside of the endoscope 1. In other words, the space 3 between each lens 25 and 26
0 is airtight with respect to the inside and outside of the endoscope 1. Therefore, it is possible to prevent water vapor from entering into this space 30. Therefore, even if water vapor gradually infiltrates into the endoscope 1 from the outer skin of the insertion section 2, etc., it does not reach the space 30. Therefore, even if the water supply operation is performed, the inner surface of the first objective lens 25 will not become cloudy. Therefore, inspection work can be continued safely.

In addition, the first objective lens 25 is exposed to a strong impact.
If the space 30 were to crack or lose its airtightness, even if water or the like would enter the space 30, it would not enter further inside than the second objective lens 26. Therefore, even in this case, internal components such as the image guide fiber 34 are not damaged, so repairs can be made easily and in a short time.

Further, since the first objective lens 25 and the second objective lens 26 in this embodiment are bonded on their respective side peripheral surfaces to the lens frame 18, airtightness and durability thereof can be greatly improved.

Note that similar effects can be obtained even if the space 30 in the above configuration is filled with an optically transparent liquid such as water or alcohol, or _N2 gas.

FIG. 3 shows a second embodiment of the present invention.

In this embodiment, not only the first objective lens 25 and the second objective lens 26 but also the rear group lenses 33 and 33 are attached to the same lens frame 41. The first objective lens 25 is attached airtightly in the same manner as above, while the rear group lenses 33, 33
The rearmost lens 42 is attached to its lens frame 41.
It was attached airtightly in the same manner as above. Note that 43 is a spacer tube.

Several spaces other than the space 30 are formed between the first objective lens 25 and the rearmost lens 42, but these spaces are also hermetically sealed.

FIG. 4 shows a third embodiment of the present invention.

In this embodiment, a ring-shaped protrusion 43 that abuts against the first objective lens 25 and a second objective lens 26 are formed on both inner peripheral edges of the aperture 24 fitted inside the lens frame 18 in the first embodiment. By forming a ring-shaped protrusion 44 that abuts against the lens frame 1.
A ring-shaped gap is formed between the inner surface of the lens 8, the aperture 24, and each lens 25, 26, and each gap is filled with adhesives 45, 46. Since the ring-shaped gap is thus formed and filled with the adhesives 45 and 46, the adhesive fixation can be ensured, and the airtightness can be further improved.

FIG. 5 shows a fourth embodiment of the present invention.

This embodiment is characterized by the method of attaching and fixing the first objective lens 25 and the image guide fiber 34.

That is, the first objective lens 25
It is directly and airtightly attached and fixed by adhesive to the inner surface of the tip of a through hole 17 formed in the main body 15 of. A lens frame 52 is fitted behind the first objective lens 25 via a flange portion 51, and furthermore, a tip end cap 35 of the image guide fiber 34 is fitted behind the lens frame 52.
The outer diameter of the tip cap 35 is slightly smaller than the inner diameter of the through hole 17 into which it is fitted, and a cylindrical gap is formed between the two.
This cylindrical gap is filled with an adhesive 53 to airtightly close the interior of the endoscope 1.

Further, the lens frame 52 includes rear group lenses 33, 33.
is included. image guide fiber 3
A lens 54 is attached to the distal end surface of the lens 4.

Therefore, the first objective lens 25 and the rear group lens 33
The space between the first objective lens 25 and the tip cap 35, including the space 30 between the first objective lens 25 and the leading edge of the lens, is airtightly closed.

FIG. 6 shows a fifth embodiment of the present invention.

This embodiment differs from the first embodiment in that the endoscope 1 is of a side viewing type and that an optical path changing prism 61 is disposed inside the first objective lens 25. And the above prism 6
1 is inserted into the groove 63 provided in the main body 15 of the tip structure part 7 while being fitted into the prism frame 62 . Further, the top surface of the prism 61 is in contact with the bottom surface of the first objective lens 25, and is fixed with adhesive in an airtight manner. That is, the space formed between the first objective lens 25 and the prism 61 is hermetically sealed from the inside and outside of the endoscope 1.

[Effect of idea]

As explained above, in the present invention, the space between the optical member constituting the observation window and the optical member located inside the observation window is configured to be airtight from the inside and outside of the endoscope. Therefore, even if the temperature drops, no condensation occurs on the optical member. In other words, it is possible to prevent the optical member, especially the inner surface of the observation window, from becoming cloudy. Furthermore, even if the airtightness of the optical member constituting the observation window were to be compromised, liquid would not penetrate into the entire interior of the endoscope, preventing serious damage, causing only minor damage, and making repairs easy.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of the distal end component of the endoscope in the first embodiment, FIG. 2 is a perspective view of the endoscope in the same embodiment, and FIG. 3 is the objective optical system in the second embodiment. The side cross-sectional views of the vicinity of the system and FIGS. 4 to 6 are side cross-sectional views of the tip components in the second to fifth embodiments, respectively. DESCRIPTION OF SYMBOLS 1... Endoscope, 2... Insertion part, 7... Tip component, 18... Lens frame, 25... First objective lens, 26... Second objective lens, 27... Mounting hole, 28, 29,53...adhesive, 30...space.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In an endoscope that incorporates an objective optical system consisting of a plurality of optical members in the distal end component and has a nozzle that opens toward an observation window of the objective optical system that is exposed to the outside. , a mounting hole for arranging a plurality of optical members is provided in the tip component, and an optical member constituting the observation window and a rear optical member located inside the observation window are each airtightly mounted to the mounting hole. An endoscope characterized in that the space between the two optical members in the attachment hole is hermetically closed. (2) The endoscope according to claim 1, wherein the space between the optical member serving as the observation window and the optical member behind the optical member is airtightly closed.