JPS62115116A - Method for preventing fogging of endoscope - Google Patents

Abstract

PURPOSE:To easily remove the fogging by water drops sticking to the surface of glass by heating objective glass cover by a heater such as direct heat fluid thereby eliminating the difference between the temp. of the glass and the temp. in the bodily cavity. CONSTITUTION:The surface of the objective cover glass 12 at a top end 4 is cleaned by cleaning water released form a nozzle 16. Air is blown from the nozzle 16 to blow off the washing water from the glass surface and thereafter the heat medium is returned to a reflux path 25. The water drops sticking to the surface of the cover glass 12 are thereby evaporated if the glass 12 is heated. The flogging generated on the surface is thus eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fog prevention device for an endoscope, and more particularly, to a dust prevention device for removing fog from an objective cover glass at the distal end of an endoscope insertion portion into a body cavity.

As we all know, inside? J! It is configured as shown in FIG. That is, the endoscope 1 includes an operating section 2 in which an eyepiece section 6, a copper 7 for air and water supply, an operating member 8, etc. are arranged, and a flexible tubular body that communicates with the operating section 2. The insertion section 3 and the light source connection section 5 constitute the main parts thereof.

Then, the objective lens 13 (see FIG. 2) disposed in the distal end 4 of the body cavity insertion section 3 guides the inside of the body cavity through the image guide optical fiber bundle 14 (see FIG. 2) to the operating section. It is designed to be viewed through an eyepiece 6 provided at 2. or,
The distal end portion 4 of the insertion portion 3 is configured as shown in FIG. 2.3. That is, a cylindrical tip fitting 11 is fixed to the distal end of the insertion portion 3 of the tubular body, and an objective lens 13 is attached to this fitting 11, and as shown in FIG. At the front, the metal fitting 11
An objective cover made of disk-shaped glass or a concave lens is attached to a lath 12 approximately at the center of the surface side, and further above the lath 12, at a symmetrical position, the tips of optical fiber bundles 18a and 18b for light guides are attached. They are fitted in a watertight manner. A cleaning nozzle 16 is disposed to protrude above the upper objective cover glass 12. This nozzle 16 is inserted into the insertion portion 3 of the tubular body, and sends air toward the surface of the cover glass 120 to the tip of the air/water pipe 15 whose tip is fitted onto the metal fitting 11 .

Configured to convey water. Note that the reference numeral 17 is a hood attached to the outer peripheral surface of the metal fitting 11.

When the body cavity insertion section 3 of the endoscope is inserted into the body cavity, the nozzle 16 allows the object to be observed to be clearly seen due to the contents of the body cavity, mucus, etc. that adhere to the surface of the objective cover glass 12. Since this is often not possible, cleaning water is sent from the nozzle 16 to wash away the deposits, and then air is sent from the nozzle 16 to blow off the washing water to clean the surface of the objective cover glass 12. Keep objective lens 13
It is used to see objects clearly.

By the way, while the temperature inside the body cavity is always constant, the temperature of the water and air sent from the nozzle 16 is as follows.
Generally lower than the temperature inside the body cavity, the surface temperature of the cover glass 12 often reaches a temperature at which the water vapor inside the body cavity becomes saturated and condenses. In this state, water droplets adhere to the surface of the cover glass 120, causing fogging. There was a drawback that the object to be observed could not be seen clearly. In addition, in order to eliminate this drawback, attempts have been made to repeatedly supply air or to make the water sent from the nozzle 16 hot water, but the Since the pipe 15 has a long distance and is thin, the temperature suddenly drops during the air or water supply, making it impossible to obtain the expected results and making it impossible to remove water droplets.

In view of the above points, an object of the present invention is to directly heat the objective cover glass using a heating means such as a thermal fluid to eliminate the humidity difference between the temperature of the objective cover glass and the temperature inside the body cavity. To provide an anti-fogging device which removes fogging caused by water droplets adhering to the surface of an objective cover glass.

According to the present invention, the structure is extremely simple, the operation is easy, and it can be automated, and it is possible to obtain the extremely remarkable effect that the above-mentioned fogging can be reliably prevented from occurring.

The present invention will be explained in detail below based on illustrated embodiments. FIG. 4 is an enlarged sectional view of the distal end portion of an endoscope incorporating the anti-fogging device of the present invention. The same parts as in the conventional example and FIG. 2 are given the same reference numerals, and details are omitted.

In the fogging prevention device of this embodiment, the objective cover is provided with a reflux path 25 for circulating a hot fluid on the outer peripheral surface of the lath 12, and a hot fluid such as hot water or hot air is flowed through the reflux path 25 to heat the cover glass 12. It was designed to keep you warm.

The reflux path 25 is connected to the cover glass 12 inside the tip fitting 11.
A fluid feed path 2 provided in the metal fitting 11 is provided in the metal fitting 11 along the outer circumferential surface of the reflux path 25.
Thermal fluid is sent from 5a, and is discharged from a fluid discharge path 25tl, which is also provided in the metal fitting 11. The fluid feed path 25a and the fluid discharge path 25b
are respectively connected to reflux pipes 26a, 26b and a fluid reflux device (not shown), which are means for supplying thermal energy.

The anti-fogging device of this embodiment configured as described above operates as follows. That is, as in the conventional method described above, the surface of the objective cover glass 12 is washed with the washing water discharged from the nozzle 16, and then air is blown through the nozzle 16 to wash the glass surface with the washing water. After blowing it away,
The cover glass 12 is heated by refluxing the hot fluid through the reflux path 25.
When heated, the water droplets adhering to the surface of the cover glass 120 described above evaporate. Therefore, cloudiness occurring on the same surface is removed.

By heating the cover glass 12 to an appropriate temperature in this manner, the water droplets are reliably evaporated, so that the cloudiness generated on the surface of the cover glass 12 can be reliably removed.

Further, the reflux path 25 may be formed by winding a pipe for refluxing the thermal fluid around the outer peripheral surface of the cover glass 12, or may be formed along the inner outer periphery of the cover glass 12. good. In addition, the temperature of the thermal fluid does not need to be high enough to damage the inner wall of the body cavity; it is sufficient to have the same temperature as the temperature inside the body cavity, and since the thermal fluid refluxes, the temperature may not drop. do not have.

Incidentally, the heating device consisting of the above-mentioned hot fluid reflux path 25 and the like may be automatically controlled by a temperature sensing member disposed near the cover glass.

The temperature sensing member is composed of a well-known temperature-voltage conversion element, and is disposed near the surface of the cover glass,
Measure the temperature when the glass becomes foggy. The sensing member is then connected to a control circuit that compares the voltage with a constant voltage and automatically opens and closes a switch of a fluid circulation device that circulates the thermal fluid.

With this configuration, when the distal end of the endoscope is inserted into a body cavity and a desired part of the body cavity is to be observed, the temperature sensing member detects that the cover glass and its vicinity have not reached a certain temperature. When this is detected, the switch is immediately closed via the control circuit, so that the hot fluid is refluxed from the fluid reflux device and the cover glass is heated. Then, when the temperature within the body cavity is reached, the switch is opened and heating automatically stops. Therefore, the cloudiness that forms on the surface of the cover glass prior to use of the endoscope is removed, and there is no risk of overheating and damaging the inside of the body cavity.

As explained above, the present invention has a simple structure that requires adding only a few parts to a conventional endoscope, and its operation is extremely simple and can be automated. It is possible to provide an extremely effective anti-fogging device that eliminates the problem.

[Brief explanation of drawings]

Is Figure 1 a typical figure? ! The schematic plan view of the mirror, Figure 2, is
The enlarged sectional view of the distal end of the endoscope shown in Fig. 1 above, and Fig. 3 shown in Fig. 2 above? J! A front view of the tip of the mirror, and FIG. 4 is an enlarged sectional view of an anti-fogging device showing an embodiment of the present invention. 1... Endoscope 4... Endoscope tip 12... Objective cover glass, 25... Thermal fluid reflux path 26a126b... Reflux pipe Fig. 1, Fig. 2

Claims (1)

[Scope of Claims] An objective cover glass provided at the tip of the endoscope, a reflux path for circulating a thermal fluid provided outside the optical path range of the effective visual field of the objective cover glass, and a reflux path for circulating a thermal fluid. What is claimed is: 1. A fog prevention device for an endoscope, comprising a means for supplying thermal fluid for supplying energy.