JPH0372293B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an endoscope with an improved switching valve for gas supply.

Generally, an endoscope is provided with a gas passageway used for replacing intestinal gas with nonflammable gas, for example. Conventionally, a spool-type valve has been used as a switching valve for controlling the opening and closing of the passage (see the specification of Utility Model Application No. 1983-44091). By the way, in the case of an endoscope, air may be supplied until the intestinal pressure reaches a dangerous value. Therefore, it has been proposed to keep the intestinal pressure below a certain value by providing the switching valve for gas supply with the function of a pressure regulating valve (see the specification of Japanese Patent Application No. 146,521/1982). This is because the valve body and the operation button, which open when the pressure in the gas line exceeds a certain level, are integrally provided, so the line can be opened by just lightly touching the operation button of the switching valve.

Generally, even when the operator does not intend to operate the switching valve, it is normal for the operator to lightly rest his/her finger on the piston and rest it. (Generally, the pressure is higher than that of air supply.) Therefore, when using this switching valve, the operator must keep his or her fingers erect and extended so as not to touch the piston. Therefore, the problem is that the operator becomes extremely tired. of course,
It is possible to set the leak valve so that it does not open unless it is pushed with strong force. However, if it is set in this way, it will no longer function effectively as a pressure regulating valve, which is rather dangerous.

The present invention has been made focusing on the above circumstances,
The purpose is to provide an endoscope equipped with a switching valve for gas supply that is safe and easy to operate by providing an appropriate amount of pushing force during gas supply operation without impairing its function as a pressure regulating valve. It's about doing.

Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 show a first embodiment of the invention. In the figure, 1 is an endoscope consisting of an insertion section 2 and an operation section 3. As shown in FIG. The operating section 3 is provided with an eyepiece section 4 and is connected to a universal cord 6 having a connector 5 at its end. In addition, the operation unit 3 includes a switching valve 7 for air/liquid feeding and a switching valve 8 for gas feeding.
and is provided. The air/liquid feeding switching valve 7 is constructed as shown in FIG. 2. That is,
A first mounting hole 10 is provided in the wall 9 that forms the operating section 3.
A bottomed cylinder 11 with one end open is fixedly attached to the first mounting hole 10 with the opening facing the outside of the operating section 3 . This cylinder 11 has an upstream side 1 of the air supply passage 12 on the peripheral wall.
2a, an upstream side 13a and a downstream side 13b of the liquid feeding passage 13 are connected above the peripheral wall of the upstream side 12a, and the downstream side 12b of the air feeding passage 12 is connected to the bottom. Also, cylinder 1
1 has a piston 14 fitted therein. This piston 14 is provided with a leak hole 15 that penetrates in the axial direction, and a communication groove 16 is formed in the middle of the outer peripheral surface. Furthermore, the cylinder 11
A collar 13 is formed at the end protruding from the cylinder 11, and a spring 18 is provided between the collar 17 and the open end surface of the cylinder 11 to bias the piston 14 outward. In the state where the piston 14 is urged outward of the cylinder 11 by the spring 18, the air/liquid feeding switching valve 7 configured as described above is connected to the upstream side 12a and the downstream side of the air feeding passage 12. The upstream side 13a and the downstream side 13b of the liquid feeding passage 13 communicate with each other on the side 12b.
and are blocked. Also, the piston 14 is connected to the spring 1
8, the upstream side 12a and downstream side 12b of the air supply passage 12 are cut off, and the upstream side 13a and downstream side 13b of the liquid supply passage 13 are connected to the communication groove formed in the piston 14. 16. Upstream side 1 of the air supply passage 12 and liquid supply passage 13
2a and 13a are led to a connector 5 provided at the end of the universal cord 6, and via this connector 5, the upstream side 12a of the air supply passage 12 is connected to an air supply pump (not shown), and the upstream side 13a of the liquid supply passage 13 is connected to the upstream side 12a of the liquid supply passage 13. are connected to liquid containers (not shown). The liquid container is configured to be pressurized with pressurized air from the air pump when the switching valve 7 for air/liquid feeding is switched to liquid feeding. Further, the downstream side 12b of the air supply passage 12 and the downstream side 13 of the liquid supply passage 13
b is inserted into the insertion section 2 and communicates within the distal end of the insertion section 2, and this communication section is connected to a nozzle 19 provided on the distal end surface 2a of the insertion section 2.

The gas supply switching valve 8 is constructed as shown in FIG. That is, a second mounting hole 31 is formed in the wall 9 of the operating portion 3, and a cylindrical valve seat mounting member 32 is tightly fitted into the second mounting hole 31. A collar 33 that contacts the inner surface of the wall 9 is formed on the inner outer periphery of the valve seat mounting member 32, and the outer portion of the valve seat mounting member 32 protrudes outward from the wall 9. ing. A male thread 34 is formed on the outer periphery of this protruding portion, and a mounting ring 35 is screwed onto this male thread 34. The valve seat mounting member 32 and the mounting ring 35 are fixedly attached to the wall 9 by sandwiching the wall 9 between the mounting ring 35 and the collar 33. Note that a ring-shaped elastic packing 36 is inserted between the second mounting hole 31 and the valve seat mounting member 32.

A cylindrical valve seat member 37 with a bottom is disposed inside the valve seat mounting member 32 . This valve seat member 3
7 has its bottom wall portion 38 airtightly attached and fixed to the inner end of the valve seat mounting member 32, and the portion other than the bottom wall portion 38 has an outer diameter smaller than the inner diameter of the valve seat mounting member 32. It is formed to have a diameter, and a passage 39 is formed on both circumferential surfaces thereof. Further, a valve seat 41 made of an annular member is screwed into the open end of the valve seat member 37. In other words,
This valve seat 41 protrudes inward from the inner wall of the valve seat member 37, and one end of the protruding portion on the bottom wall portion 38 side serves as a valve seat surface 43 against which a valve body 42, which will be described later, is abutted. The inside of this cylindrical valve seat member 37 is used as a valve chamber 44.

Further, a valve body 42 is disposed within the valve chamber 44 . That is, the valve body 42 has a valve shaft 4 concentrically disposed within the valve seat member 37 forming the valve chamber 44 thereof.
5, and a valve portion 46 made of an elastic material is attached and fixed to the inner end of this valve shaft 45. During standby, the elastic valve portion 46 hits the valve seat surface 43 and the valve chamber 44
and the passage 39.
Therefore, a disc-shaped flange 47 is integrally formed on the outwardly projecting end of the valve shaft 45, and is disposed in the passage 39 between the flange 47 and the valve seat member 37, and is arranged in the valve seat member 37. A coil spring 48 as a valve body biasing means is wound around the member 37.
is inserted. And this coil spring 48
As a result, the valve body 42 is energized, and the valve portion 46 comes into contact with the valve seat surface 43 and stands by.

Note that the flange 47 is attached to the valve seat mounting member 32.
Since the valve body 42 moves up and down using the inner peripheral surface as a guide, the valve body 42 can be moved without wobbling.

A communication hole 51 is formed in the flange 47 to communicate the inside and outside. Also, when the valve body 42 is pushed in, the flange 47 comes into contact with the valve seat 41.
A communication cutout hole 52 for communicating the passage 39 and the valve chamber 44 side is formed at the upper end of the valve chamber 44 .

A first tube 54 forming an upstream side 53a of the gas feeding passage 53 and a second tube 55 forming a downstream side 53b of the gas feeding passage 53 are connected to the bottom wall portion 38 of the valve seat member 37. has been done. The first tube 54 is connected to communicate with the bottom of the valve chamber 44, and the second tube 55 is connected to the passage 39.

The upstream side 53a of the gas supply passage 53 is led to the connector 5 through the universal cord 6, and is connected to a gas cylinder (not shown) storing nonflammable gas. The downstream side 53b of the gas supply passage 53 is connected to the middle of the downstream side 12b of the gas supply passage 12. Also,
On the downstream side 12b of the air supply passage 12, a check valve is provided between the connection point of the downstream side 53b of the gas supply passage 53 and the air/water supply switching valve 7 to block the flow toward the switching valve 7 side. 56 is inserted.

On the other hand, in the gas supply switching valve 8, the valve seat mounting member 32 has an operation button 5 for operating the valve body 42.
7 is detachably attached. The operation button 57 is formed by integrally molding a biasing member 59 made of a cylindrical wall body on the periphery of a finger rest main body 58 to urge the finger rest main body 58 outward. These are integrally formed of an elastic material such as rubber. moreover,
An engaging protrusion 61 that fits and engages the valve seat mounting member 32 is provided on the inner circumferential surface of the open end of the biasing member 59.
and an engagement groove portion 62 located inwardly from this. That is, the engaging protrusion 61 tightly fits into the fitting annular groove 63 formed on the outer peripheral side surface of the valve seat mounting member 32 along the circumferential direction thereof.
Further, a flange portion 64 formed from the periphery of the protruding outer end of the valve seat mounting member 32 is tightly fitted into the engagement groove portion 62 . Furthermore, the upper end surface 65 of the flange portion 64 is obliquely inclined, and the annular fitting groove 65 corresponds to this.
The upper side walls 66 of 3 are also inclined obliquely so that they come into close contact with each other. Further, the front end side wall 67 of the engagement protrusion 61 is formed in a tapered shape, and when the biasing member 59 is fitted into the valve seat mounting member 32, the engagement protrusion 61 touches the upper end surface 65 of the flange 64. The flange portion 64 can be easily climbed over. In addition, by tightly fitting the biasing member 59 to the valve seat mounting member 32 in this way, the valve seat mounting member 32 is airtightly sealed by its contact surface. However, if the internal pressure increases to a relatively high pressure, it is also possible to cause a leak.

A base portion 68 facing the flange 47 of the valve body 42 is formed on the inner surface of the finger rest main body 58 of the operation button 57, and there is a certain distance between the base portion 68 and the flange 47 during standby. It is configured such that a distance l intervenes.

Next, the operation of the gas supply switching valve 8 having the above configuration will be explained. First, in the standby state shown in FIG. 3, the valve body 4 is
2 is pushed up, and the valve portion 46 hits the valve seat surface 43 of the valve seat 41 and is in a closed state. Valve chamber 44 and passage 39
Since the gas supply passage 53 is cut off from the
No gas is sent through the pipe.

On the other hand, when performing air and water supply, the gas cylinder is separated from the gas supply passage 53. At this time, the pressurized air from the air pump is flowing into the cylinder 11 of the air/liquid feeding switching valve 7 through the upstream side 12a of the air feeding passage 12. Therefore, as shown in FIG. 2, when in the standby state, the cylinder 11
The pressurized air that has flowed into the downstream side 1 of the air supply passage 12
Piston 14 with significantly lower flow path resistance than Piston 2b
is released into the atmosphere through the leak hole 15. In other words, air is not supplied to the nozzle 19.

Furthermore, when supplying air into the body cavity, the leak hole 15 of the piston 14 may be closed with fingers. As a result, the pressurized air escaping from the leak hole 15 pushes open the check valve 56 and opens the downstream side 12b of the air supply passage 12.
It is supplied from the nozzle 19 into the body cavity through the nozzle 19.

Next, when performing liquid feeding, push in the piston 14 while blocking the leak hole 15 of the piston 14 of the air/liquid feeding switching valve 7 with your fingers, and
The upstream side 12a and downstream side 12b of piston 1
4 and the upstream side 1 of the liquid feeding passage 13.
3a and the downstream side 13b through the communication groove 1 of the piston 14.
6. As a result, the liquid container is pressurized by the pressurized air from the air pump, so
The liquid contained in this liquid container is transferred to the liquid sending passage 13.
It is sent through the nozzle 19 and flows out from there.

Furthermore, when it is desired to supply nonflammable gas into the body cavity, a gas cylinder is connected to the gas supply passage 53, and the operation button 57 of the gas supply switching valve 8, which has been in the standby state as described above, is pressed. As shown in FIG. 4, when the biasing member 59 is bent and the pushing force increases, the base portion 68 hits the flange 47 of the valve body 42, and by further pushing the valve body 42, the biasing force of the coil spring 48 applies. Push down against it. As a result, the valve seat 41 and the valve portion 46, which have been joined up to now, are separated, and the passage 39 and the valve chamber 44 are brought into communication. As a result, the gas supply passage 53 is opened to supply nonflammable gas to the nozzle 19 side. In addition,
At this time, due to the action of the check valve 56, the air does not flow into the air/liquid feeding switching valve 7. Moreover, if the push-in to the operation button 57 is loosened, the operation button 57 will be pressed against the biasing member 5
9 returns to its original position and separates from the valve body 42 (FIG. 3).

By the way, if air is accidentally supplied excessively into the body cavity during the above-mentioned air supply operation, and the pressure inside the body cavity increases abnormally or more than necessary, the following actions will be taken. That is, the pressure within the body cavity reaches the passage 39 of the gas supply switching valve 8 through the downstream side 12b of the gas supply passage 12 and the second tube 55, and is further applied to the valve portion 46 of the valve body 42. and,
When a high pressure above a certain level is applied under the above circumstances, the valve body 42 is pushed open against the urging force of the coil spring 48 and the elasticity of the valve portion 46, and excess air, etc. is released from there. Therefore, the pressure inside the body cavity does not exceed a certain level and danger can be prevented. This relief pressure can be set to an appropriate value by calculating the force of the coil spring 48 from the pressure receiving area of the valve portion 46 and the weight of the valve body 42 assembly. In addition, when the pressure becomes higher than the above pressure, for example, the gas supply passage 5
When the gas cylinder is connected to the gas cylinder 3 and there is no leakage through the passage 53, the space between the attachment ring 35 and the biasing member 59 is pushed wide and the gas leaks directly to the outside.

In addition, when cleaning the gas supply switching valve 8 and the passages 12, 53 communicating therewith, as shown in FIG.
Remove the cleaning opening 7 from the outer periphery of the mounting ring 35.
1 is fitted in a watertight manner to form an injector 72 such as a syringe.
A cleaning liquid is injected through the mouth body 71 from the mouth body 71. Note that the opening body 71 is formed in the same manner as the end of the biasing member 59 on the fitting side. However, the push-in portion 73 is formed so that the valve body 42 is pushed in and opened when the valve body 42 is fitted. As a result, the switching valve 8 is brought into an open state simply by attaching the mouth body 71.

The operation feel of the operation button 57 can be selected according to the operator's preference by changing its shape, wall thickness, hardness, etc. For example, if hard rubber is used as the material, the pushing force will be heavy, and if the distance l is increased as shown in FIG. 6, the pushing stroke can be increased. Further, the operation button 57 can also be made larger.

FIG. 7 shows yet another embodiment. This is because the operation button 81 is made of plastic with good high-frequency insulation and is slidably inserted in an airtight manner into a cylindrical member 82 screwed into the mounting ring 35, and further between the mounting ring 35 and the operation button 81. A coil spring 83 is interposed therebetween as a biasing means.

As explained above, the present invention creates a space between the valve body and the operation button in the gas supply switching valve that functions as a pressure regulating valve, and increases the pressing force of the operation button appropriately until the gas supply operation. Even if the operator waits with his or her finger on the operation button, gas will not be delivered inadvertently. In other words, you can rest your fingers on the control buttons, so you don't get tired physically or mentally. Furthermore, since the above-mentioned intervals and the like can be arbitrarily selected, it is possible to set the force and pushing stroke that are easy to operate. On the other hand, when the inside of the body cavity reaches a certain level, the valve body opens and air leaks, which is not affected by the operation button, so the pressure regulation effect can be ensured and it is safe.

[Brief explanation of drawings]

FIG. 1 is a schematic structural explanatory diagram of an endoscope showing an embodiment of the present invention, FIG. 2 is a sectional view of the switching valve for air and water supply, and FIG. 3 is a sectional view of the switching valve for gas supply. Figure 4 is a cross-sectional view when the gas supply switching valve is pressed in, and Figure 5 is a cross-sectional view when it is on standby.
The figure is a cross-sectional view of the switching valve for gas feeding with a cleaning spout fitted, and FIGS. 6 and 7 are cross-sectional views of the switching valve for gas feeding showing other different embodiments. . 1... Endoscope, 8... Gas supply switching valve, 42
... Valve body, 53 ... Gas supply passage, 57 ... Operation button, 59 ... Biasing member, l ... Distance.

Claims (1)

[Claims] 1. In an endoscope in which the operating section is provided with a switching valve that controls the opening and closing of a gas passageway that supplies gas into the body cavity, the gas passageway is connected to the air passageway downstream of the air supply switching valve. Along with connecting to the middle part,
The switching valve has a valve body that automatically opens when the pressure on the downstream side of the gas supply passage reaches a certain level or more, and a valve body that is provided apart from the valve body during standby and is pushed in to close the valve body. An endoscope comprising: an operation button for opening.