JP2004135890A - Endoscope conduit switching device - Google Patents

Abstract

An annular seal member for sealing between an outer peripheral portion of a piston-like member and an inner peripheral surface of a cylinder-like member can always be assembled at a set value according to a set value, and stable sealing performance and operation without variation. Provided is an endoscope conduit switching device capable of ensuring the performance.
A compression member is provided for compressing an annular seal member by pressing the annular seal member in an axial direction, and the compression member is fixed to a piston-like member in a state where the annular seal member is compressed to an appropriate outer diameter. I did it.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a conduit switching device for an endoscope.
[0002]
[Prior art]
In general, a pipe line switching device for an endoscope is configured such that a piston-like member is inserted in a cylinder-like member connected in the middle of a fluid pipe for suction or air supply, water supply, etc. so as to be able to advance and retreat in an axial direction, and a cylinder is provided. The connection state of the fluid conduit is switched by moving the piston-like member forward and backward within the member.
[0003]
FIG. 6 shows an example of such a conventional suction pipe line switching device for an endoscope, in which a piston-like member is provided between an inner peripheral surface of a cylindrical member 91 and an outer peripheral portion of an end of a piston-like member 92. Sealed by an O-ring 93 made of a resilient rubber material and mounted on the outer peripheral surface of the member 92, the O-ring 93 is fitted into a circumferential groove 94 formed in the piston-like member 92 ( For example, Patent Document 1).
[0004]
[Patent Document 1]
JP-A-8-252216 [0005]
[Problems to be solved by the invention]
In the above-described device, the amount of crushing of the O-ring 93 caused by the O-ring 93 being sandwiched between the inner peripheral surface of the cylindrical member 91 and elastic deformation is determined by the size of the circumferential groove 94 and the size of the cylindrical member 91. It is determined by the relationship with the inner diameter of the O-ring 91 and the diameter of the O-ring 93 itself.
[0006]
However, there is a processing error to be allowed for each of such dimensions, and if the integration of the processing errors is a combination biased in a direction to increase or decrease the crushing amount of the O-ring 93, the O-ring 93 In some cases, the crushing amount becomes significantly larger than the original set value and the operation of the piston-like member 92 becomes extremely heavy, and conversely, the crushing amount becomes significantly smaller than the set value and fluid leakage occurs due to insufficient sealing. is there.
[0007]
Therefore, the present invention can always assemble the crushing amount of the annular seal member for sealing between the outer peripheral portion of the piston-like member and the inner peripheral surface of the cylinder-like member according to the set value, and achieves a stable sealing property without variation. It is an object of the present invention to provide an endoscope conduit switching device capable of ensuring operability.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a pipe line switching device for an endoscope according to the present invention includes a piston-shaped member in an axial direction inside a cylinder-shaped member connected in the middle of a fluid pipe piped to the endoscope. An annular seal member made of a resilient material for being inserted and retractable and sealing the inner peripheral surface of the cylindrical member is attached to the outer peripheral portion of the piston member. In a pipeline switching device for an endoscope configured to switch a connection state of a fluid pipeline by moving a tubular member in an axial direction, a compression member that presses and compresses an annular seal member in an axial direction is provided. The compression member is fixed to the piston-like member while the annular seal member is compressed to an appropriate outer diameter.
[0009]
In addition, the annular seal member is mounted in a compressed state by being sandwiched between a flange portion of a flanged tubular member screwed to an end portion of the piston-like member and an end surface of the piston-like member. The amount of compression of the annular seal member may be changed by changing the screwing state of the annular seal member and the cylindrical member.
[0010]
Also, the cross-sectional shape of the outer peripheral portion of the annular seal member that comes into contact with the inner peripheral surface of the cylindrical member may be formed in a shape protruding outward in a substantially “eight” shape.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
FIG. 3 shows an overall configuration of a suction path of the endoscope. An operation section 2 is connected to a base end of an insertion section 1 covered with a flexible tube, and an upper half of the suction section switching device. 3 are arranged.
[0012]
The cylindrical member 31 of the suction pipe line switching device 3 is connected in the middle of the suction pipes 4 and 5, and the end of the suction pipe 4 which goes backward is connected to an external suction device (not shown) and goes downward. The suction tube 5 communicates with a treatment instrument insertion channel 6 that opens at the distal end of the insertion section 1. Reference numeral 7 denotes a forceps stopper attached to the forceps insertion port.
[0013]
FIG. 4 shows a standby state of the suction line switching device 3, and FIG. 5 shows a suction state. The cylindrical member 31 is arranged in the operation unit 2 and is fixed to the operation unit 2 by a fixing nut 32 so as to open outward. 33 is an O-ring for sealing.
[0014]
The end of the suction tube 4 communicating with the external suction device is opened and connected to the side wall surface of the intermediate portion of the cylindrical member 31, and the end of the suction tube 5 communicating with the treatment instrument insertion channel 6 is connected to the cylindrical member 31. An opening is connected to the bottom end.
[0015]
The piston-like member 34 is inserted into the cylinder-like member 31 so as to be able to advance and retreat in the axial direction, and the head of the piston-like member 34 projecting outward from the operation unit 2 is operated via a connection ring 35. Button 36 is attached.
[0016]
At the center position of the operation button 36, an index member 37 made of, for example, red plastic is mounted between the connection ring 35 and the operation button 36 so that the protruding end surface can be seen from the outer surface.
[0017]
The piston-like member 34 and the operation button 36 are integrally urged outward by a compression coil spring 38, and the receiving cylinder 39 which receives the base end side of the spring 38 is in a predetermined state. As described above, the stopper serves to prevent the cylindrical member 31 from slipping out of the inside.
[0018]
An inner peripheral portion of a lower end portion of a fixed ring 40 made of an elastic plastic material or a rubber material lined integrally with the receiving cylinder 39 is hooked and engaged with a protruding end portion of the fixed nut 32, and is engaged with the piston-shaped member 34. A unit including the operation button 36 is fixed to the cylindrical member 31.
[0019]
If the fixed ring 40 is elastically deformed and disengaged from the fixed nut 32, the piston-like member 34 can be pulled out of the cylindrical member 31 together with the operation button 36 and the like.
[0020]
Reference numerals 42 and 43 denote pins protruding laterally from the piston-like member 34 for restricting the rotation of the piston-like member 34 with respect to the cylinder-like member 31, and rotation-preventing engagement of the pins. Is a straight groove.
[0021]
The piston-like member 34 is provided with a communication hole 44 which is opened at a side surface at a middle portion and an end at the back side, and has a resilient rubber material having a shape surrounding a periphery of the opening at the side surface. An opening seal member 50 is fitted into the piston-shaped member 34 and is in close contact with the inner peripheral surface of the cylindrical member 31.
[0022]
An annular seal member 48 made of a resilient rubber material or the like is provided with a flange 49a of a flanged tubular member 49 (compression member) that is screwed to a rear end of the piston-like member 34 and a piston-like member. 34, and is mounted in a compressed state by being sandwiched between the end surface 34 and the end surface of the head.
[0023]
The annular seal member 48 has a cross-sectional shape of an outer peripheral portion that is in contact with the inner peripheral surface of the cylindrical member 31 in a substantially “8” shape so that the sliding resistance against the inner peripheral surface of the cylindrical member 31 is reduced. It is formed in a shape protruding outward.
[0024]
FIG. 1 shows a state before the annular seal member 48 is attached to the piston-like member 34, and the tubular member 49 is formed to have an outer diameter dimension that is perfectly inserted inside the annular seal member 48, A flange portion 49a is formed on one end side, and a male screw 49b is formed on an outer peripheral portion on the other end side.
[0025]
On the other hand, a female screw 34a to be screwed with the male screw 49b of the tubular member 49 is formed at the far end of the piston-like member 34, and the male screw 49b of the tubular member 49 is screwed there. Accordingly, as shown in FIG. 2, the annular seal member 48 is mounted in a compressed state while being sandwiched between the flange 49 a of the tubular member 49 and the end surface of the piston-like member 34.
[0026]
Therefore, by changing the screwing state between the male screw 49b of the cylindrical member 49 and the female screw 34a of the piston-like member 34, the axial amount of compression ΔA of the annular sealing member 48 changes, and the annular sealing member 48 is accordingly changed. The outer diameter D of the annular seal member 48 changes due to the elastic deformation of the member 48.
[0027]
Therefore, by adjusting the outer diameter D of the annular seal member 48 to an optimal size and fixing the cylindrical member 49 to the piston member 34 by adhesion, the cylindrical member 49 is sandwiched between the inner peripheral surface of the cylindrical member 31 and the cylindrical member 49. The resulting crushing amount of the annular seal member 48 can be assembled so as to always be in the most appropriate state as set.
[0028]
4 and 5, the circumferential groove 45 formed on the outer peripheral portion of the piston-like member 34 has a ventilation cut-out portion 46 formed by partially cutting off the side surface of the piston-like member 34, It communicates with the outside air through a vent hole 47 formed near the head.
[0029]
Therefore, in the standby state shown in FIG. 4, the outside air is sucked into the suction pipe 4 communicating with the external suction device through them, and the space between the two suction pipes 4 and 5 is the rear end of the piston member 34. Sealed by the annular seal member 48 and the opening seal member 50 mounted on the portion, suction from the suction tube 5 communicating with the treatment instrument insertion channel 6 is prevented.
[0030]
From this state, as shown in FIG. 5, when the operation button 36 is pressed with a fingertip to push the piston-like member 34 into the cylindrical member 31, the side opening of the communication hole 44 formed in the piston-like member 34 When the two suction tubes 4 and 5 come to a position facing the opening of the suction tube 4 communicating with the suction device and communicate with each other through the communication hole 44, suction is performed through the treatment instrument insertion channel 6.
[0031]
At this time, the periphery of the side opening of the communication hole 44 is sealed by the opening seal member 50, and the periphery of the opening on the back side of the communication hole 44 is sealed by the annular seal member 48, so that the circumferential groove 45 and the ventilation cut External air is prevented from being sucked into the suction pipe 4 through the portion 46 or the like.
[0032]
In such an operation, since the crushing amount of the annular seal member 48 arranged at the far end of the piston-like member 34 is assembled according to the set value, the state in which the sealability and the operability coexist is obtained. It can be secured stably.
[0033]
Note that the present invention is not limited to the above embodiment, and for example, the present invention can be applied to an air / water switching operation device of an endoscope or the like.
[0034]
【The invention's effect】
According to the present invention, a compression member that presses and compresses the annular seal member in the axial direction is provided, and the compression member is fixed to the piston-like member while the annular seal member is compressed to an appropriate outer diameter. By doing so, the amount of crushing of the annular seal member that seals between the outer peripheral portion of the piston-like member and the inner peripheral surface of the cylinder-like member can always be assembled according to the set value, and stable sealing performance without variation and operation can be achieved. Property can be ensured.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a state before an annular seal member is attached to a piston-like member according to an embodiment of the present invention.
FIG. 2 is a side sectional view showing a state in which an annular seal member is attached to a piston-like member according to the embodiment of the present invention.
FIG. 3 is a schematic diagram showing an entire configuration of a suction path of the endoscope according to the embodiment of the present invention.
FIG. 4 is a side half-sectional view of a standby state of the conduit switching device of the endoscope according to the embodiment of the present invention;
FIG. 5 is a side sectional view showing a suction state of the conduit switching device of the endoscope according to the embodiment of the present invention.
FIG. 6 is a side sectional view showing a part of a conventional endoscope conduit switching device, with the part omitted.
[Explanation of symbols]
3 Suction line switching device 31 Cylinder member 34 Piston member 34a Female screw 48 Annular seal member 49 Cylindrical member (compression member)
49a collar 49b male screw

Claims (3)

A piston-like member is inserted into a cylinder-like member connected in the middle of a fluid conduit piped to the endoscope so as to be able to advance and retreat in the axial direction, and seals the gap between the cylinder-like member and the inner peripheral surface. An annular seal member made of a resilient material is attached to the outer peripheral portion of the piston-like member, and the fluid-line connection state is formed by moving the piston-like member in the cylinder-like member in the axial direction. In an endoscope conduit switching device configured to be switched,
A compression member for pressing the annular seal member in the axial direction to compress the annular seal member is provided, and the compression member is fixed to the piston-like member in a state where the annular seal member is compressed to an appropriate outer diameter. An endoscope conduit switching device. The annular seal member is mounted in a compressed state by being sandwiched between a flange portion of a flanged tubular member screwed to an end portion of the piston-like member and an end surface of the piston-like member, and the piston 2. The conduit switching device for an endoscope according to claim 1, wherein the amount of compression of the annular seal member changes by changing a threaded state between the tubular member and the tubular member. The endoscope according to claim 1 or 2, wherein a cross-sectional shape of an outer peripheral portion of the annular seal member that is in contact with an inner peripheral surface of the cylindrical member is a shape protruding outward in a substantially "eight" shape. Pipe line switching device.

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