JPS6349499B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an endoscope having an airtight structure in which a sliding portion is provided with an elastic sealing member.

Generally, an endoscope is equipped with a sliding part such as a diopter ring for adjusting the diopter of the eyepiece and an operation knob for bending the curved part of the tip of the insertion tube. . These sliding parts are provided with elastic sealing members pressed by a pressing member to keep the sliding parts, ie, the inside of the endoscope, airtight.

By the way, in order to enable the operator to operate the sliding portion with light force, measures such as reducing the amount of tightening of the sealing member by the pressing member or using a soft sealing member have been implemented. There is. Therefore, when such an endoscope is placed in a high-pressure steam sterilizer and sterilized, the sealing member is deformed due to the difference between the pressure inside the can of the high-pressure steam sterilizer and the pressure inside the endoscope. However, there was a problem in that the sliding part of the endoscope could not be kept airtight.

Therefore, conventionally, as in Japanese Utility Model Application Publication No. 54-57039, an opening communicating with the inside of the endoscope was provided in the endoscope jacket, and a bellows was connected to this opening. The internal pressure and the pressure inside the endoscope were kept equal to prevent the airtightness of the sliding portion from being impaired. However, with this structure, the bellows must be quite large in order to follow changes in the internal pressure of the high-pressure steam sterilizer, which changes in the range of -0.9 to 2.2 atmospheres. Accordingly, large autoclaving equipment must be used. Moreover, if a bellows is provided at the operating section or the insertion section of the endoscope, there are problems such as the bellows getting in the way and making it difficult to operate the endoscope.

This invention has been made based on the above circumstances, and its object is to increase the amount of pressure applied to the sealing member provided on the sliding part when the temperature is high and to reduce it when the temperature is low. It is an object of the present invention to provide an endoscope that can ensure the airtightness of the sliding part with a simple structure without impairing the operability of the sliding part.

An embodiment of the present invention will be described below with reference to the drawings. In the figure, 1 is the endoscope body. The endoscope main body 1 includes an insertion section 2, an operating section 3, and a light guide cable 4 connected to the operating section 3, and the inside of the endoscope main body 1 is sealed from the outside. The insertion section 2 is formed by connecting a distal end component 7 to the distal end of a flexible tube section 5 via a bending tube section 6, and the bending tube section 6 can be bent by an operation knob 8 provided on the operation section 3. It is becoming more and more common. The tip component 7 is provided with an observation window 9, an illumination window 10, and an opening 11 for the forceps channel. An image guide 12 made of an optical fiber bundle has one end facing the observation window 9, and this image guide 12 is led to the operating section 3 through the insertion section 2, and is guided to the operating section 3 provided in the operating section 3. The other end is opposed to the eyepiece lens 14 of the lens. Further, a light guide (not shown) has one end facing the illumination window 10, and this light guide is connected to the insertion section 2 and the operation section 3.
The light guide cable 4 is guided to a connector 15 provided at the tip thereof through the light guide cable 4. This connector 15 is designed to be connected to a light source device (not shown), and guides illumination light generated by the light source device from the illumination window 10 into the body cavity via the light guide.
The portion illuminated by this illumination light can be observed through an observation window 9 at an eyepiece 13. Further, the opening 11 of the forceps channel communicates with a forceps insertion port 16 provided in the operating section 3 via a forceps channel (not shown) passed through the insertion section 2 and the operating section 3.

On the other hand, the eyepiece section 13 is constructed as shown in FIG. That is, the eyepiece portion 13 is provided with a cylindrical portion 17, and a holding frame 18 holding the eyepiece lens 14 is slidably provided on this cylindrical portion 17. A connecting pin 19 is provided protruding from the outer peripheral surface of the holding frame 18, and this connecting pin 19 protrudes from a through hole 20 formed in the cylindrical portion 17.
A recess 22 from which flanges 21, 21 protrude from the upper and lower ends is formed on the outer circumferential surface of the cylindrical portion 17, and a diopter ring 23 is rotatably fitted into this recess 22. A connecting pin 19 protruding from a through hole 20 of the cylindrical portion 17 is engaged with an inclined groove 24 formed on the inner circumferential surface of the dowel ring 23 . Therefore, when the diopter ring 23 is rotated, the holding frame 18 moves up and down, so that the focal position of the eyepiece lens 14 can be adjusted. Attachment grooves 25, 25 are formed in the upper and lower ends of the outer peripheral surface of the diopter ring 23, that is, in the portions facing the flanges 21, 21 of the cylindrical portion 17, respectively. Resilient sealing members, such as O-rings 26, 26, are provided. That is, the O-rings 26, 26 are pressed against the flanges 21, 21 of the cylindrical portion 17 by the diopter ring 23, and keep the sliding portion between the diopter ring 23 and the cylindrical portion 17 airtight. The diopter ring 23 is made of a shape memory alloy. That is, the diopter ring 23 is formed to exhibit a shape memory effect at a predetermined temperature, for example, around 70° C., and is in slight pressure contact with the O-rings 26, 26 at around room temperature, as shown in FIG. When heated to around 70°C, the O-rings 26, 2 expand in the radial direction as shown in Figure 3.
6 is strongly crushed to improve the airtightness of the sliding portion between the diopter ring 23 and the cylindrical portion 17.

Further, the operation knob 8 is provided on the operation section 3 as shown in FIG. 4. That is, a bearing part 28 is opened in the outer wall 27 of the operating part 3, and a drum 30 around which the operating wire 29 is wound is attached to the bearing part 28.
A rotating body 32 having a large diameter portion 31 that rotatably fits into the bearing portion 28 is connected to an inner wall 33 of the operating portion 3.
The rotating body 32 is rotatably supported by a fixed shaft 34 projecting from the rotating body 32, and the operating knob 8 is connected to an end projecting from the outer wall 27 of the operating section 3 of the rotating body 32. A mounting groove 35 is provided in the large diameter portion 31 of the rotating body 32.
is engraved along the entire circumferential length. In this mounting groove 35, an annular sealing member 38 is provided, which is made by pasting a sheet packing 37 of Teflon, rubber, etc. as an elastic sealing member on the outer surface of a spring member 36 having a substantially U-shaped cross section. Seal member 3
8 keeps the sliding portion between the bearing portion 28 and the large diameter portion 31 of the rotating body 32 airtight. The spring member 36 constituting the seal member 38 is made of a bimetal such as brass and amber or mone metal and nickel copper, and at around room temperature the sheet packing 37 is attached to the bearing portion 28 as shown in FIG.
The inner peripheral surface of the mounting groove 35 is in slight pressure contact with the outer peripheral surface of the mounting groove 35, but when the operating section 3 is heated to around 70 degrees Celsius, the spring member 36 made of bimetal expands and becomes a sheet as shown in FIG. Packing 37 to bearing part 28
and the mounting groove 35 to improve airtightness between them.

In addition, in FIG. 1, 39 is a push button for air supply, and 40 is a push button for water supply.

Next, a case will be described in which the endoscope having the above configuration is placed in a high-pressure steam sterilizer and sterilized. First, as shown by A in FIG. 6, the endoscope body 1 is placed in a can of a high-pressure steam sterilizer at atmospheric pressure and around 80°C. Then, the diopter ring 23 of the eyepiece 13 exhibits a shape memory effect and the O-rings 26, 2 as shown in FIG.
6 is crushed to improve the airtightness between the diopter ring 23 and the cylindrical portion 17, and to form a seal member 38 provided in the mounting groove 35 of the large diameter portion 31 of the rotating body 32 to which the operating knob 8 is connected. The spring member 36 deforms as shown in FIG. 5 and strongly presses the seat packing 37 against the inner circumferential surface of the bearing portion 28 and the outer circumferential surface of the mounting groove 35. Next, as shown by B in Figure 6, the inside of the can is depressurized to a nearly vacuum state of -50 to -60 cmHg to eliminate the air inside the can, and then high-temperature steam is injected into the can. The internal pressure is increased to 2 as shown by C.
The pressure is set to ~2.2 atm and the temperature is set to around 130℃. At this time, a pressure difference occurs between the inside and outside of the endoscope body 1, and there is a possibility that steam may enter the inside through the sliding portion provided on the endoscope body 1. However, in the eyepiece part 13, which is a sliding part, the diopter ring 23, which is a shape memory alloy, exhibits a shape memory effect and strongly crushes the O rings 26, 26, and the large diameter part 31 to which the operation knob 8 is connected cannot be mounted. The spring member 36 made of bimetal provided in the groove 35 deforms into a state in which its U-shape expands and strongly presses the seat packing 37 against the bearing portion 28 and the mounting groove 35, so that it is not connected to the outside of the endoscope body 1. Even if a pressure difference occurs between the inside and the inside, steam will not enter the inside through the sliding part. Then, the inside of the can was placed in the state shown by C in Figure 6 for about 10 minutes.
After the endoscope main body 1 is sterilized and disinfected by leaving it for about a minute, the steam inside the can is exhausted and the pressure inside the can is
As shown by D in the figure, the vacuum is applied to about -70 cmHg to evaporate all the water inside the can and dry the endoscope body 1. Finally, air is injected into the can to return the pressure inside the can to atmospheric pressure as shown by E in FIG. 6, thereby completing sterilization.

Once the sterilization and disinfection are completed in this manner, the endoscope body 1 is taken out of the can and returned to room temperature, and the diopter ring 23 and spring member 36 return to their original shapes before being heated. In other words, the diopter ring 23 is in slight pressure contact with the O-rings 26, 26, and the sheet packing 37 attached to the spring member 36 is also in slight pressure contact with the bearing portion 28 and the mounting groove 35. The diopter ring 23 and the operating knob 8 can be rotated with light operating force.

Note that this invention is not limited to the above embodiment,
For example, the diopter ring 23 is made of bimetal,
The spring member 36 of the seal member 38 may be formed of a shape memory alloy, and the shape of these members and the shape of the seal member pressed by these members are not limited at all.

Furthermore, the sliding part according to the present invention is the eyepiece part 13.
The present invention can be applied not only to the operation knob 8 but also to other sliding parts provided on the endoscope body 1, such as the sliding parts of the air supply push button 39 and the water supply push button 40. It is clear that this can be done.

As described above, the present invention provides an endoscope having an airtight structure in which the sliding portion is sealed by a sealing member and a member that presses the sealing member. It is made of a metal whose shape changes according to temperature changes so that the amount of pressure applied to the sealing member is large and becomes smaller when the temperature is low. Therefore, in normal endoscopy, the sliding part can be operated with light force, and when sterilizing at high pressure and high temperature with an autoclave, the airtightness of the sliding part can be maintained. This can prevent steam from entering the endoscope body. Moreover, since the member that presses the sealing member, that is, the essential member that constitutes the sliding part, is made of metal that changes the amount of pressure on the sealing member depending on temperature deformation, the structure becomes complicated and the endoscope It does not cause enlargement.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a perspective view of the entire endoscope, Fig. 2 is a sectional view of the eyepiece, and Fig. 3 is a deformed state of the diopter ring when heated. FIG. 4 is a cross-sectional view of a portion of the operating section where the operating knob is provided, FIG. 5 is a cross-sectional view showing the deformed state of the sealing member when heated, and FIG.
The figure is an explanatory diagram showing changes in the internal pressure of the high-pressure steam sterilizer. 8... Operation knob (sliding part), 13... Eyepiece part (sliding part), 23... Diopter ring, 26... O ring (sealing member), 36... Spring member, 37... Seat Packing (sealing member).

Claims (1)

[Scope of Claims] 1. An endoscope having an airtight structure that has a sliding portion, and the sliding portion is sealed by an elastic sealing member and a member that presses the sealing member. An endoscope characterized in that the pressing member is formed of a metal whose shape changes according to temperature changes so that the amount of pressing against the sealing member is large when the temperature is high and becomes small when the temperature is low. 2. The endoscope according to claim 1, wherein the member that presses the sealing member is made of a shape memory alloy. 3. The endoscope according to claim 1, wherein the member that presses the sealing member is made of bimetal.