JPH10225434A - Fluid duct changeover device of endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the changeover operating force quantity of a fluid duct and to relieve the fatigue of an operator by forming the inner diameter of a cylinder body in a part where a seal member passes through when a piston body is moved among a plurality of prescribed positions to be larger than that of the cylinder body in a part where the seal member is close. SOLUTION: In an air and water supply changeover operating valve 20, air supplied from a air supplying tube 6 passes through an air passable hole 31 in a stand-by state and discharged from a leak hole 32. When the leak hole 32 is clocked in this state, air inside the air passable hole 31 is supplied to an air and water supply channel tube 3 by way of a connecting tube 9 and an inhaling operation valve 40. When an operation button 22 is pushed-in after that, water from the water supplying tube 7 is supplied to the channel tube 3 through a water passable hole 33. In this case, the inner diameter of the part 38 where an O-ring 30 passes through when the piston body 26 is moved is formed to be larger than that of the part where the piston body 26 is in a prescribed position and also the O-ring 30 is close so that the operating force quantity of the piston body 26 is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope fluid line switching device for switching the communication state of a fluid line of an endoscope.

[0002]

2. Description of the Related Art Many endoscopes are provided with a fluid conduit such as an air supply / water supply conduit or a suction conduit. The operation unit of the endoscope is provided with a switching operation valve for switching the communication state of the fluid conduit.

[0003] Such a switching operation valve generally has a structure in which a piston body is inserted into a cylinder body to which a fluid conduit is connected so as to be able to advance and retreat in the axial direction. The connection state of the fluid conduit is switched by stopping the piston body at a plurality of predetermined positions by an operation with a fingertip.

In such a switching operation valve, it is necessary to prevent fluid leakage from a gap between the inner peripheral surface of the cylinder body and the outer peripheral surface of the piston body. Such a seal member is attached to the outer peripheral portion of the piston body.

[0005]

However, since such a sealing member is used in a crushed state to exert a sealing function, it acts as a resistance against sliding operation of the piston body in the cylinder body. I do. For this reason, the amount of operation force for switching the fluid pipeline is increased, which is one of the causes of the fatigue of the operator performing the endoscope operation.

Accordingly, the present invention provides a fluid line switching device for an endoscope which can reduce the amount of force required to switch the fluid line and reduce the fatigue of an operator who operates the endoscope. Aim.

[0007]

In order to achieve the above object, a fluid line switching device for an endoscope according to the present invention is connected to a fluid line of an endoscope so as to change the communication state of the fluid line. What is claimed is: 1. A fluid line switching device for an endoscope for performing a switching operation, comprising: a cylinder body to which said fluid pipeline is connected; And a piston body for switching the connection state of the fluid pipe, and a resilient annular member provided on the outer periphery of the piston body so as to prevent fluid leakage by being in close contact with the inner surface of the cylinder body. In the fluid line switching device for an endoscope having a sealed member, when the piston body moves between the plurality of predetermined positions, the inner diameter of the cylinder body of the portion through which the seal member passes, Piston body is characterized in that it is formed to a larger diameter than the inner diameter of the cylinder body portion where the sealing member comes into close contact when in the predetermined position.

In the portion where the inner diameter of the cylinder body is large, the seal member may be prevented from touching the inner peripheral surface of the cylinder body, and when the piston body is at the predetermined position. The amount of collapse of the seal member may be made smaller than that.

The fluid line switched by the piston body may be an air / water supply line or a suction line.

[0010]

Embodiments of the present invention will be described with reference to the drawings. FIG. 2 shows an endoscope, in which 1 is an insertion unit, and 2 is an operation unit connected to the base end of the insertion unit 1.

The distal end of the channel tube 3 inserted through the entire length of the insertion portion 1 is open at the distal end surface of the insertion portion 1, and serves as an air / water supply / suction port 4. The base end of the channel tube 3 is connected to the air / water switching operation valve 20 and the suction operation valve 40 arranged in the operation unit 2.

Reference numerals 21 and 22 denote a cylinder body and operation buttons of the air / water switching operation valve 20, respectively. Reference numerals 41 and 42 projecting to the outside are a cylinder body and operation buttons of the suction operation valve 40.

Cylinder body 21 of air / water switching operation valve 20
Is connected to an air supply tube 6 for supplying air and a water supply tube 7 for supplying water. In addition, a suction tube 8 communicating with a suction device disposed outside is connected to the cylinder body 41 of the suction operation valve 40. Reference numeral 9 denotes a connection pipe arranged to connect the side portions of the two cylinder bodies 21 and 41 to each other.

FIG. 1 is an enlarged view of the air / water switching operation valve 20 and the suction operation valve 40. However, the suction operation valve 40 side is shown in a state where a mechanism arranged in the cylinder body 41 is removed.

Air / water switching operation valve 20 and suction operation valve 40
Are fixed nuts 23, 43, respectively.
And is arranged so as to open to the outer surface of the operation unit 2. 24 and 44 are O-rings for sealing.

The air supply tube 6 and the water supply tube 7 are spaced apart from each other,
1 side. The suction tube 8 is connected to a side surface of the cylinder body 41 of the suction operation valve 40.

The bottoms of the two cylinders 21 and 41 are connected to each other by communication pipes 10 and 11, and one end of the communication pipe 10 is connected to the base end of the channel tube 3.

Cylinder 21 of air / water switching operation valve 20
Inside, a piston body 26 is slidably fitted in the axial direction. The outer end of the piston body 26 projects outside from the opening of the cylinder body 21, and the operation button 22 is attached thereto.

34, the piston body 26 is
The stopper is a stopper for preventing slipping out of the fixing nut 23 and is detachably locked to the fixing nut 23 by an integrally molded plastic cover 35.

A compression coil spring 36 is interposed between the operation button 22 and the stopper 34, whereby the piston 26 is urged in a direction to protrude from the cylinder 21.

In FIG. 1, the right half of the air / water switching operation valve 20 is located at a first predetermined position where the piston body 26 is fully pushed outward by a compression coil spring 36 until the piston body 26 hits a stopper 34. The left half shows a state in which the piston body 26 is at a second predetermined position where the piston body 26 is fully pushed into the cylinder body 21.

A vent hole 31 formed at the axial position of the piston body 26 is open to the outside at a leak hole 32 formed at the center of the protruding end of the operation button 22. Vent 31
A communication hole 27 communicating with the connection pipe 9 and a communication hole 25 communicating with the air supply tube 6 in a standby state shown in the right half are formed.

A check valve 28 made of a resilient rubber material is arranged in a recess formed in the communication hole 27 communicating with the connection pipe 9. Blocks fluid flow into the interior.

On the bottom side of the piston body 26, a water passage hole 33 is formed at an axial position, and is opened on the bottom surface of the piston body 26. Then, as shown in the left half, a communication hole 29 that communicates with the water supply tube 7 when the piston body 26 is fully pushed into the cylinder body 21.
Are drilled.

In the air / water switching operation valve 20 configured as described above, in a standby state in which nothing is operated, the air fed from the air supply tube 6 passes through the ventilation hole 31 and is discharged from the leak hole 32 to the atmosphere. Is done.

When the leak hole 32 is closed with a fingertip, the air sent from the air supply tube 6 into the vent hole 31
The gas is sent out to the channel tube 3 through the cylinder 41 of the suction operation valve 40 through the connection pipe 9, and air is supplied from the air supply / water supply suction port 4.

Then, as shown in the left half, when the operation button 22 is fully pushed while the leak hole 32 is closed with a fingertip, water sent from the water supply tube 7 passes through the water passage hole 33. The water is sent out to the channel tube 3 and water is supplied from the air / water supply / suction port 4.

However, in the mechanism for switching the fluid conduit by sliding the piston body 26 in the cylinder body 21 in this manner, the mechanism between the inner peripheral surface of the cylinder body 21 and the outer peripheral surface of the piston body 26 is not provided. It is necessary to prevent the fluid from leaking from the gap.

Therefore, as shown in FIG. 1, circumferential grooves are formed on both sides of the outer periphery of the piston body 26 with the communicating holes 25, 27, 29, etc. therebetween, and the circumferential grooves are formed in the circumferential grooves. Is provided with an O-ring 30 for sealing.

Each of the O-rings 30 is formed of a resilient material such as rubber or the like.
Is in close contact with the inner peripheral surface of the cylinder body 21 when it is at a first predetermined position where it is fully pushed outward and when it is at a second predetermined position where it is fully pushed into the cylinder body 21. It is in a crushed state.

As a result, when the piston body 26 is at the first and second predetermined positions, leakage of fluid from the gap between the inner peripheral surface of the cylinder body 21 and the outer peripheral surface of the piston body 26 is completely prevented. Will be blocked.

However, the cylinder body 21 is formed of the piston body 2
The inside diameter of the portion 38 through which the O-ring 30 passes when the piston 6 moves between the first and second predetermined positions is such that the O-ring 30 is in close contact when the piston body 26 is at the first or second predetermined position. It is formed to be larger than the inner diameter of the portion to be formed.

As a result, when the O-ring 30 passes through the large diameter portion 38, the O-ring 30
Are not touched at all, so that there is no resistance to the movement of the piston body 26.

However, the O-ring 30 may be in contact with the inner peripheral surface of the large-diameter portion 38. At that portion, the amount of collapse of the O-ring 30 is reduced. The adhesion force is reduced, and the resistance to the movement of the piston body 26 is reduced.

Therefore, as shown in the right half and the left half of FIG. 1, when the piston body 26 is at the first and second predetermined positions, the cylinder body 21 and the piston body 26 Is completely performed to prevent leakage of fluid, and when the piston body 26 moves between the first and second predetermined positions, the amount of collapse of the O-ring 30 is reduced. The pressing operation of the operation button 22 can be easily performed with a light force.

In the above embodiment, an example is shown in which the present invention is applied to the air / water switching operation valve 20, but the invention may be applied to the suction operation valve 40 and the like.

[0037]

According to the present invention, when the piston moves between predetermined positions, the inner diameter of the cylinder through which the sealing member passes is brought into close contact with the sealing member when the piston is at the predetermined position. By forming the diameter larger than the inner diameter of the cylinder body of the part, the amount of collapse of the seal material during the operation of moving the piston body is reduced, so the amount of operation force for switching the fluid pipeline is reduced, and the endoscope It is possible to reduce fatigue of the operating operator.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a fluid line switching device according to an embodiment of the present invention.

FIG. 2 is an overall schematic diagram of the endoscope according to the embodiment of the present invention.

[Explanation of symbols]

 21 Cylinder body 26 Piston body 30 O-ring 38 Large diameter part

Claims (5)

[Claims] 1. A fluid line switching device for an endoscope, which is connected to a fluid line of an endoscope to switch a communication state of the fluid line, wherein the fluid line is connected. A cylinder body, a piston body which is inserted into the cylinder body so as to be able to advance and retreat in the axial direction and stops at a plurality of predetermined positions to switch a connection state of the fluid pipeline, and a resilient annular member; A fluid passage switching device for an endoscope having a seal member provided on an outer peripheral portion of the piston body so as to prevent fluid leakage by being in close contact with an inner surface of the body; The inner diameter of the cylinder body where the seal member passes when moving between the positions, the cylinder inside the part where the seal member is in close contact when the piston body is at the predetermined position. A fluid line switching device for an endoscope, wherein the device is formed to have a diameter larger than an inner diameter of a body. 2. The fluid line switching device for an endoscope according to claim 1, wherein the seal member does not touch the inner peripheral surface of the cylinder body at a portion where the inner diameter of the cylinder body is large. 3. The endoscope according to claim 1, wherein the crush amount of the seal member is smaller at a portion where the inner diameter of the cylinder body is formed larger than when the piston body is at the predetermined position. Fluid line switching device. 4. A fluid line switching device for an endoscope according to claim 1, wherein the fluid line switched by the piston body is an air / water supply line. 5. A fluid line switching device for an endoscope according to claim 1, wherein the fluid line switched by the piston body is a suction line.