JPH04258915A - Endoscope for high temperature environment - Google Patents

Abstract

PURPOSE:To use the endoscope even under an inferior high temperature environment by covering doubly the endoscope with an inner tube and an outer tube, cooling it doubly by allowing cooling gas and a cooling liquid to flow to the inner tube, and between the inner tube and the outer tube, respectively, and attaching a quartz plate to a photodetecting window. CONSTITUTION:A protective tube main body is a multiple tube structure consisting of an inner tube 2 and an outer tube 3, an endoscope 1 is contained in the inner tube 2 and cooling gas 4 of N2, Ar and air, etc., is allowed to flow, and also, a cooling liquid 5 of water, etc., is allowed to flow between the inner tube 2 and the outer tube 3. The tip part of this protective tube is constituted of a stop plug 8 of the inner tube, a stop cover 9 of the outer tube 3 and a partition wall 43 for forming a return passage 6 of the cooling liquid 5 so that the cooling liquid 5 dows not flow into the inner tube 2, although the endoscope 1 is covered with the cooling gas 4 and the cooling liquid 5. Also, in the inner tube 2 and the outer tube 1, a window through which the endoscope 1 photodetects is provided, this window 10 is covered with a transparent quartz plate 11 through a receiving frame 13 and fixed by a holding frame 12, and in this receiving frame 13, an outflow port 14 of the cooling gas 4 is provided.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is suitable for direct visual observation and observation, such as in high-temperature locations where flames and molten metal are scattered, in high-temperature locations where water vapor and smoke dust are dense, and in low-pressure and high-temperature locations such as vacuum furnaces. It concerns an endoscope for viewing areas that cannot be monitored.

0002

2. Description of the Related Art An endoscope to which the present invention is directed refers to a light-receiving sensor such as a fiberscope (also called a borescope) or a rigid scope with a lens structure. Conventionally, protective tubes for endoscopes have a structure in which the endoscope is housed in a cylindrical tube and a protective gas is passed through, as in Japanese Utility Model Application No. 61-20537 and No. 62-198232. protection tubes are known.

Furthermore, as disclosed in Japanese Utility Model Application Publication No. 62-198232, in order to protect the lens of an endoscope from flying objects, the tip of the protective tube is bent into an L-shape, and a reflecting mirror is attached to the bent portion. A protective tube is known in which a protective tube is installed and a cleaning inert gas is blown into the protective tube. However, with such conventional methods that only flow protective gas around the endoscope in the protective tube or protect only the tip of the protective tube from flying debris, it is difficult to avoid flames or atmospheres with temperatures exceeding several 100 degrees There is a problem in that it is not possible to monitor or observe areas where droplets of molten metal are scattered, areas where water vapor or smoke dust is concentrated and high temperatures, or areas with reduced pressure and high temperatures such as vacuum furnaces.

0004

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to propose an endoscope for high-temperature environments that can be used even in harsh high-temperature environments.

[0005]

[Means for Solving the Problems] The present invention covers the periphery of an endoscope with a double tube consisting of an inner tube and an outer tube with one end closed, and a light receiving window of the endoscope is opened near the one end. At the same time, the openings of the inner tube and the outer tube are closely connected by a cylindrical partition wall, and the opening of the light receiving window is covered with a transparent quartz plate via a receiving frame, and the receiving frame is provided with an outlet for cooling gas. On the other hand, it is an endoscope for use in high-temperature environments, in which the other end of the inner tube is provided with an inlet for the cooling gas, and the other end of the outer tube is provided with an inlet and an outlet for the coolant, respectively.
Preferably, a nozzle for spraying cooling or cleaning gas onto the outer surface of the transparent quartz plate is provided around the light-receiving window, and the tip including the light-receiving window is covered with a vacuum seal cap whose light-receiving portion is made of a transparent quartz plate. This is an endoscope for use in high temperature environments. This endoscope is usually used by being mounted on a position moving device.

[0006]

[Operation] Generally, the light receiving part and the light transmitting part of an endoscope are made of quartz fiber, glass lens, plastic lens, etc.
It is made of rubber or plastic tubes, and its heat resistance temperature is 80°C, and at most 150°C. Therefore, the present invention covers the endoscope with a double tube consisting of an inner tube and an outer tube, allows cooling gas to flow through the inner tube housing the endoscope, and further provides cooling liquid between the inner tube and the outer tube. This makes it possible to provide double thermal insulation cooling by flowing heat to the endoscope, so that endoscopes installed in locations where high-temperature flames or atmospheres exceeding several 100 degrees Celsius, molten metal droplets, high-temperature smoke, or dust can be temperature can be maintained below.

Further, in the present invention, since the light-receiving portion of the endoscope is covered with a transparent quartz plate, the endoscope itself does not come into direct contact with radiant heat or high-temperature flying objects. Further, if necessary, a nozzle for spraying cooling or cleaning gas onto the quartz plate can be provided, so that the quartz plate can be prevented from softening, deterioration, or staining.

Furthermore, according to the present invention, since the distal end of the endoscope including the light receiving window can be covered with a vacuum seal cap if necessary, it is also possible to observe and monitor a place with reduced pressure and high temperature. Furthermore, in the present invention, since the endoscope can be mounted on the position moving device, it is possible to quickly adjust the position of the observation section and quickly evacuate in case of an emergency.

[0009] As described above, according to the present invention, since heat is doubly blocked, heat transfer (conduction, convection, radiation) to the endoscope can be completely prevented. Even in flames, the endoscope can be maintained semi-permanently below its heat-resistant temperature. Furthermore, transparent quartz can block high-temperature flying objects. In addition, when the tip of the endoscope is completely covered with a vacuum seal cap whose light-receiving part is made of a transparent quartz plate, it is necessary to
It can be inserted into a reduced pressure section of about -3 torr for monitoring and observation.

Next, the present invention will be explained based on examples.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a cross-sectional view of a protective tube body of the present invention housing an endoscope. FIG. 2 is a sectional view of the tip of the protective tube of the present invention, which is provided with a nozzle for spraying cooling and cleaning gas onto the outer surface of the transparent quartz plate of the light receiving window of the endoscope. Figure 3 shows the protection of the present invention in which a vacuum seal cap whose light receiving portion is made of transparent quartz is provided at the tip of the protective tube, which consists of the light receiving window of the endoscope, the stopper of the endoscope, and the lid that forms the passage for the cooling liquid. FIG. 3 is a cross-sectional view of the tip of the tube.

FIG. 4 is a layout diagram when the protective tube of the present invention housing an endoscope and its position moving device are incorporated into a water atomizing device to monitor and observe the flow of molten metal. FIG. 5 is a plan layout diagram of the endoscope housing protection tube of FIG. 4 and its position moving device. The protection tube main body shown in Figure 1 is
It has a multi-tube structure consisting of an inner tube 2 and an outer tube 3, and the endoscope 1 is housed in the inner tube 2, and a cooling gas 4 such as N2, Ar, or air is supplied.
At the same time, a cooling liquid 5 such as water is caused to flow between the inner tube 2 and the outer tube. The tip of this protective tube is provided with a passageway through which the cooling gas 4 and the cooling liquid 5 pass over the endoscope 1, but the cooling liquid 5 enters and returns so that the cooling liquid 5 does not flow into the inner tube 2. 6 is formed by a through hole 7, a stopper 8 of the inner tube 2, a stopper cap 9 of the outer tube 3, and a cylindrical partition wall 43 that tightly connects the inner tube and the outer tube.

A window 10 through which the endoscope 1 receives light is provided in the inner tube 2 and outer tube 3, and the window 10 is covered with a transparent quartz plate 11 via a receiving frame 13 and fixed with a holding frame 12. 13
An outlet 14 for the cooling gas 4 is provided at the outlet 14 . By doing so, the endoscope can perform double thermal isolation of the cooling gas 4 and the cooling liquid 5. Furthermore, by jetting out the cooling gas 4 from the transparent quartz plate 11 and the cooling gas outlet 14 at a speed greater than the moving speed of outside air, the endoscope 1 can be shielded from flying objects and dirt can be prevented. Furthermore, by tightening the stopper 15, the endoscope 1 prevents the inner tube 2 from shifting.

Here, the cooling gas 4 is passed through a cooling gas inlet pipe 16 so as to pass through a gap with the inner pipe 2 into which the endoscope 1 is inserted.
The ends of the endoscope 1 and the inner tube 2 are sealed with a seal packing 19. The cooling liquid 5 is introduced from a cooling liquid inlet pipe 17 at the base of the protection tube and discharged from an outlet pipe 18 connected to a return passage 6 and a through hole 7 for the cooling liquid 5 at the tip of the protection tube. Of course, the outlet pipe 18 for the cooling liquid 5 can also be connected to the return passage 6 or the through hole 7 for the cooling liquid 5 from the outside of the outer tube 3 .

[0015] The protective tube of the present invention is made of copper, steel,
Made of metal materials such as aluminum. Furthermore,
In addition to the side viewing type endoscope shown in FIG.
A direct viewing type endoscope can also be used by installing the endoscope in the direction of . FIG. 2 shows an installation diagram of a gas spray nozzle for cooling and cleaning on the outer surface of a transparent quartz plate. Transparent quartz plate 11 attached to the light receiving window 10 of the endoscope 1 at the tip of the protection tube
In order to more reliably cool the outer surface of the window and keep it clean, a gas blowing nozzle 20 is provided around the light receiving window 10, and a gas such as N2, Ar, or air is supplied from the blowing gas inlet pipe 21 at a speed higher than that of the outside air. It is sprayed onto the entire outer surface of the transparent quartz plate 11 at a high speed.

FIG. 3 shows a protective tube of the present invention in which a vacuum seal cap whose light-receiving portion is made of transparent quartz is attached to the tip of the protective tube. It consists of a light receiving window 10 provided in the inner tube 2 and outer tube 3 of the endoscope 1, a stopper 15 of the endoscope 1, a stopper lid 9 of the outer tube 3 forming a cooling liquid passage 6, and a packing 27. A vacuum seal cap 24 with a vacuum-sealed transparent quartz plate 22 is attached to the tip of the protection tube with an O-ring 2.
3 and tighten with the fitting screw 25. The cooling gas 4 is led out of the protection tube from the cooling gas outlet pipe 26. With this vacuum-resistant protection tube, it is possible to monitor and observe the inside of a vacuum with a temperature of several hundred degrees Celsius or more and a vacuum of about 10-3 torr.

FIG. 4 shows a side view of the case where the protective tube of the present invention shown in FIG. 1 housing an endoscope and its position moving device are incorporated into a water atomization device to monitor and observe the injection flow of molten metal. A layout diagram is shown. Further, FIG. 5 is a plan layout diagram of FIG. 4. Molten metal injection stream 29 from tundish 28
(for example, molten steel) is sprayed by a high-speed water jet 32 sprayed from a water nozzle 31, and metal powder 30 (for example, steel powder) is sprayed.
When manufacturing molten steel, blockage of molten steel in the water nozzle 31 hinders production the most. Therefore, in order to monitor and observe the injection flow of molten metal in a high-temperature atmosphere of several hundred degrees Celsius, a device that can be moved freely is required.

For example, the protective tube of the present invention shown in FIG.
3. Fix with the tightening metal fittings. This imaging optical equipment storage box 33
is connected by a cable 35 connected to a pneumatically and hydraulically operated cylinder 34. In addition, the cooling gas inlet pipe 16,
The cooling liquid inlet pipe 17, the cooling liquid outlet pipe 18, and the imaging signal cable 40 can be housed in a cable carrier 39 and moved. In addition, the imaging signal cable 40
to a picture receiver, such as a VCR or television. This position moving device allows the endoscope 1 stored in the protective tube to
The position of the light receiving window 10 of the protection tube can be freely set while the light receiving window 10 remains fixed in the protection tube.

[0019]

Effects of the Invention The present invention provides a protective tube for housing an endoscope with a multi-tube structure consisting of an inner tube and an outer tube. The endoscope was surrounded by a double layer of water to cool it, making it possible to monitor and observe areas with high-temperature atmospheres of several 100 degrees Celsius.

Furthermore, since the transparent quartz plate attached to the light receiving window and the cooling gas can be ejected from the outlet provided in the receiving frame of the transparent quartz plate at a speed higher than the moving speed of the atmosphere,
It can shield the endoscope from heat and prevent the adhesion and contamination of flying foreign objects. In addition, a vacuum seal cap was attached to the tip of the protection tube, making it possible to monitor and observe vacuum locations with temperatures of several hundred degrees Celsius.

Furthermore, since a position moving device is attached to the protection tube, the position of the light receiving window can be set freely.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the main body of a protective tube of the present invention that houses an endoscope.

FIG. 2 is an installation diagram of a gas spray nozzle that sprays cooling and cleaning gas onto the outer surface of the transparent quartz plate of the light receiving window of the protection tube of the present invention that houses an endoscope.

FIG. 3 is a diagram showing how the vacuum seal cap is attached to the protection tube of the present invention.

[Fig. 4] A position moving device equipped with the endoscope of the present invention is incorporated into a water atomization device to monitor the injection flow of molten metal.
This is an example to be observed, and its side layout is shown.

FIG. 5 is a plan layout diagram of FIG. 4;

[Explanation of symbols]

1 Endoscope 2 Inner pipe 3 Outer tube 4 Cooling gas 5 Cooling liquid 6 Cooling liquid passage 7 Cooling liquid passage hole 8 Inner pipe stopper 9. Outer tube stopper lid 10 Endoscope light receiving window 11 Transparent quartz plate 12 Presser frame 13 Transparent quartz plate receiving frame 14 Cooling gas outflow hole 15 Endoscope stopper 16 Cooling gas inlet pipe 17 Cooling liquid inlet pipe 18 Cooling liquid outlet pipe 19 Seal packing 20 Gas spray nozzle 21　Blow gas inlet pipe 22 Vacuum sealed transparent quartz plate 23 O-ring 24 Vacuum seal cap 25 Vacuum seal cap fitting screw 26 Cooling gas outlet pipe 27 Packing 28 Tundish 29 Molten metal injection flow 30 Metal powder 31 Water nozzle 32 Water jet 33 Storage box for imaging optical equipment 34 Cylinder 35 Cable 36 Track rail 37 V-groove guide wheel 38 Reversing shaft and bearing 39 Cable bear 40 Imaging signal cable 41 Lens 42 Glass fiber 43 Partition wall

Claims (4)

[Claims] Claim 1: The endoscope is surrounded by a double tube consisting of an inner tube and an outer tube that are closed at one end, and a light receiving window of the endoscope is opened near one end, and the inner tube and the outer tube are opened. The parts are closely connected with a cylindrical partition wall, and the opening of the light receiving window is covered with a transparent quartz plate through a receiving frame, and the receiving frame is provided with an outlet for cooling gas, while the other end of the inner tube is provided with an outlet for the cooling gas. is the inlet of the cooling gas,
An endoscope for use in high-temperature environments, characterized in that the other end of the outer tube is provided with an inlet and an outlet for cooling fluid. 2. The endoscope for use in a high temperature environment according to claim 1, further comprising a nozzle provided around the light receiving window for spraying cooling or cleaning gas onto the outer surface of the transparent quartz plate. 3. The endoscope for use in a high temperature environment according to claim 1, wherein the distal end portion including the light receiving window is covered with a vacuum seal cap whose light receiving portion is made of a transparent quartz plate. 4. The endoscope for high temperature environments according to claim 1, wherein the endoscope for high temperature environments is mounted on the position moving device.