JPS5843417A - Heat resistant endoscope - Google Patents

Abstract

PURPOSE:To provide a device which can function normally in high-temp. environment by providing cooling medium guides through which a cooling medium is circulated and flexible heat insulating layers contg. heat resistant plastics, enclosing the guides on the circumference of a head part and a connecting part. CONSTITUTION:An endoscope consists of a head part 10 wherein a solid-state image sensing element is used for a pick up system for endoscope images and an operating part which operates said part, both of which are connected by a connecting part 12 having flexibility. An objective lens 16 and an illuminating window 18 of the image pickup system are provided to the end face 14 of the part 10 to constitute a direct viewing type endoscope. The part 10 and the part 12 have a light guide 20 for feeding the illuminating light from a light source to the window 18, a cable 22 for feeding the driving signal and image signal of the solid-state image sensing element, and a flexible sleeve 26. A pair of flexible tubes 28A, 28B are wound spirally on the outer side of the sleeve 26, and the pipes 28A, 28B are formed of heat resistant plastics in such a way that a cooling medium is fed in their inside. The tubes are covered with a sheath 32 of heat resistant plastics.

Description

DETAILED DESCRIPTION OF THE INVENTION - The present invention relates to an endoscope, particularly a heat-resistant endoscope used in a high temperature environment.

Conventionally, heat-resistant endoscopes have been rigid endoscopes made of heat-resistant metal. This is because the head section, which has the imaging system and illumination system, and the operation section that visually displays the internal vision image when these are manually operated, are connected by an original connection part, so for example, a complicated system such as a din or engine. It was not possible to insert it into an internal structure. It was often used for internal observation of straight parts such as welded parts of sheet twill.

So-called flexible endoscopes with flexible connecting parts include artificial rubber coated with polyurethane, which can be used in environments with relatively moderate temperatures; is below 150°C, so it cannot be used in many high-temperature industrial applications.

On the other hand, in industrial endoscopes, for example, complex devices such as the inside of an M-Ira, the inside of a jet engine, and blades are kept in a high-temperature state immediately after the operation is stopped, that is, in a state close to that of an operating state. There is a request to observe the inside. This is because for equipment maintenance purposes, it is preferable to grasp the state as close to the operating state as possible. Therefore, the purpose of the present invention is to meet these demands and prevent the inside of a complicated equipment from being exposed to the inside of a complex equipment in a high-temperature environment. It is desired to provide a flexible heat-resistant endoscope that can be inserted and function normally.According to the present invention, this object is achieved by the following heat-resistant endoscope. That is, this internal view i consists of a head part, a flexible connecting part and an operating part, and a cooling medium conduit for circulating a cooling medium around at least a part of the head part and the connecting part. The heat-resistant glass surrounding the 01 flexibility 0 insulation layer and! According to one aspect of the invention, the coolant conduit includes a tube made of heat resistant Zola plastic wrapped around at least a portion of the head portion and the coupling portion.

According to another aspect of the invention, the cooling medium conduit and the heat insulating layer are integrally formed in a bellows-like shape that surrounds at least a portion of the head portion and the connecting portion and allows the entire cooling medium to flow therethrough. Contains a flexible tube made of heat-resistant glass.

Next, embodiments of the heat-resistant endoscope according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a partially cutaway sectional view showing an embodiment of a heat-resistant endoscope according to the present invention. This endoscope includes a head section 10 that uses a solid-state imaging device (not shown) such as a charge-coupled device (COD) as an imaging system for internal images;
The operating section ′(
(not shown) and a flexible connecting part 12 that connects the head part 10, and the connecting part 12 is actually several meters long, but it is shortened by omitting illustration in the middle. ′( is shown.

An objective lens 16 of an imaging system is mounted on the end surface 14 of the head section 10.
and an illumination window 18, constituting a direct-viewing endoscope. The head portion 1o and the connecting portion 12 are connected to a light guide 201 that sends illumination light from a light source (not shown) to the illumination window 18.
'A flexible sheath 26 that accommodates a cable 22 for transmitting a drive signal and an image signal for the collective image sensor, a wire 24 for controlling the orientation of the head portion 1o, and the like is provided.

A pair of flexible tubes 28A and 28B are spirally wound and wound on the outside of the portion 26, and both tubes 28A and 28B are connected near the tip of the head portion 1O (3).
o). The tubes 28A and 28B are made of heat-resistant glass,
For example, it is made of aromatic nylon, polyimide, polyamide, etc., and has a hollow mother plate inside to allow a liquid or gaseous cooling medium to pass through.

The whole is further covered with the same heat-resistant glass sheath 32. These heat-resistant glass tubes 28A and 28B1 and sheath 32 are
For example, aromatic nylon has a melting point of 410 to 490.
Polyimide decomposes at 480°C, so it can withstand temperatures of at least 400°C. In the illustrated embodiment, tubes 28A and 28B are constructed separately from sheath 32, which allows tubes 28A and 28B to be molded separately from sheath 32.
8A and 28B function to maintain the same state even when the direction of the head portion 1G is changed by the wire 24. However, these do not necessarily have to be constructed separately, and the pipes 28A and 28B may be integrally molded with the sheath 32. Further, the sheath 26 may be omitted at least in the connecting portion 12.

By the way, a cooling medium is caused to flow through the pair of tubes 28A and 28B by an external driving source as shown by the corresponding arrows. Therefore, the refrigerant is supplied from the starting end 34A of the tube 28A, spirals around the sheath 26, travels inside the tube 28A in the direction of the arrow, turns back at the joint 30, and returns to the tube 28B.
Proceed through the endoscope and return to the end of 4BK.For example, when this endoscope is inserted into a jet engine that has just stopped operating, the heat that enters from the outside through the sheath 32 is transferred to the tube 28.
Absorbed by the refrigerant medium running in A and 28B, sheath 2
Protect the inside of 6 from high heat. The cooling medium may be a liquid such as water or a gas such as chilled air.
The warmed refrigerant discharged from 4B may be recooled by a cooling device (not shown) and then returned to the starting end 84A for recirculation. Also, there are cooling media that use the heat of vaporization, such as Freon and liquefied nitrogen.

May be used.

Although the embodiment shown in FIG. 1 is designed so that the cooling medium flowing through one pipe 28A is turned around at the joint 30 and returns to the other pipe 28B, it is not necessary to perform the KW in this way. Good too. For example, only the pipe 28A connected to the pipe 28B may be provided, and the refrigerant may be supplied from the starting end 34A and discharged to the outside at the joint portion 3o. In addition, the temperature conditions of the environment in which the endoscope is used,...
The temperature inside the sheath 26 is maintained at an appropriate value by selecting a flow rate suitable for the characteristics of the cooling medium used (its cross-sectional shape is rectangular rather than circular) and selecting a flow rate suitable for the characteristics of the cooling medium used. As described above, the endoscope according to the present invention can prevent the temperature rise inside the sheath 26 under high-temperature environmental conditions. In the case of endoscopes, this is effective in maintaining normal operation and preventing thermal damage, thereby improving reliability. Note that the present invention relates to a fiber optics using an optical fiber image bundle.

It goes without saying that this also applies to -zo.

FIG. 2 shows another embodiment of the heat-resistant endoscope according to the present invention. In the figure, components and elements similar to those in the embodiment of FIG. 1 are designated by the same reference numerals. In this implementation example, the endoscope sheath 266
The total length of the hip, that is, the height.

, □. , 1ゎ, □1 belly, δ envelope 1. As shown in cross section in the figure, the inside of the bellows 50 forms a space 52, which is filled with a cooling medium. The ends 54 and 56 of the bellows 50 are sealed to the sheath 26 to prevent leakage of this cooling medium.

Tubes 58 and 60 are attached near these ends 54 and 56, respectively, and the hollow interiors of the tubes 58 and 60 communicate with the interior space 52 of the bellows 50. Cooling medium can therefore be supplied to space 52 as indicated by arrow A from one of these tubes, for example tube 58, and discharged from the other tube, for example 60, as illustrated by arrow B. This discharged refrigerant may be cooled by a cooling device and returned to the pipe 58.

The cooling medium may be the same as in the embodiment of FIG. 1, and therefore may be liquid or gas. The bellows 50 and the tubes 58 and 60 are made of the heat-resistant, heat-resistant plastic material described in connection with the embodiment of FIG. 1 above. Therefore, even if this endoscope is used in a high-temperature environment, the refrigerant in the space 62, which is constantly replaced, absorbs the heat that enters from the outside, so it is possible to prevent the temperature inside the sheath 26 from rising.
Also, since the bellows 50 is flexible, the entire continuous portion 12 can be bent into a container.
0, which is particularly effectively used for observing the inside of devices connected to endoscopes.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway sectional view showing an embodiment of the heat-resistant endoscope according to the present invention, and FIG. 2 is a partially cutaway sectional view showing another embodiment of the heat-resistant endoscope according to the present invention. io "...Head part 12...-Connecting part"26' -... Sheath 28A, 28B... Tube 8'2, -... Sheath 50 1..., Bellows 58J60... Tube 7

Claims (1)

[Scope of Claims] 1. An endoscope comprising a head portion, a flexible connecting portion, and an operating portion, including a cooling medium conduit for circulating a cooling medium around at least a portion of the head portion and the connecting portion. and a flexible heat-insulating layer comprising a heat-resistant plastic surrounding the conduit. 2. The endoscope according to claim 1, wherein the cooling medium guide path includes a tube made of heat-resistant glass wound around at least a portion of the head portion and the connecting portion. Tokoru-resistant, heat-resistant endoscope. 3. In the endoscope according to claim 1, the cooling medium guide path and the heat insulating layer are integrally formed to surround at least a portion of the head portion and the connecting portion, and contain a cooling medium therein.
A heat-resistant endoscope comprising a bellows-shaped flexible tube made of heat-resistant plastic through which water flows.