JPH09256951A - Fluid introducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a leak out of fluid after it is received in a vessel under pressure, by providing a fluid circulating path connecting a peripheral surface opening part of a fluid introducing device and a communication hole. SOLUTION: A gas introducing device has a plug unit 12. When this plug unit 12 is mounted in a large diametric part 13, a clearance is generated between an internal peripheral surface of the large diametric part 13 and an external peripheral surface of a small diametric part 30b. This clearance is a gas circulating path 37 which is a fluid circulating path. A gas introducing nozzle of a gas supply device is connected to an outer side opening part 32 of the plug unit 12, inert gas, for instance, nitrogen gas is press supplied into a cylinder main unit through a gas introducing path 34, gas circulating path 37 and a small diametric part 14. Here, a first O ring 35 is mounted in the plug unit 12, so as to prevent leaking out of nitrogen gas to the outside from a clearance between an internal peripheral surface of the large diametric part 13 and an external peripheral surface of the plug unit 12. After nitrogen gas is press fed into the cylinder main unit so as to lead to a prescribed pressure, the plug unit 12 is further screwed until its tip end face leads to a bottom part of the large diametric part 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid introducing device, and more particularly, a fluid capable of introducing a fluid into a container containing a fluid in an airtight or liquid-tight manner and effectively preventing leakage of the introduced fluid. Regarding the introduction device.

[0002]

2. Description of the Related Art Conventionally, a double seal connecting terminal device attached to a submerged motor pump has a structure as shown in FIG.

As shown in FIG. 9, a conventional double-seal connection terminal device 50 has a cylindrical intermediate pipe 52 having openings at both ends and flanges 51 at both ends, and a first conductor insertion through-hole. A pump-side base 54 having a hole 53, a tubular cable drawing nozzle 56 having a flange 55 having an opening, an atmosphere-side base 58 having a second conductor inserting through hole 57, and a first conductor 59. And a second conductor 60, and one flange 51 of the intermediate pipe 52 is overlapped with the flange 55 of the cable drawing nozzle 56 via the pump-side base 54 so as to be coupled and fixed, and the other flange of the intermediate pipe 52. Flange 51 and atmosphere side base 5
8 are overlapped and fixed together, the first conductor 59 is inserted through the first conductor insertion through hole 53 of the pump side base 54, and the second conductor insertion through hole 57 of the atmosphere side base 58 is inserted through the first conductor 59. The first conductor 59 and the second conductor 60 are mechanically coupled to each other in the intermediate pipe 52 so as to be electrically conductive so as to pass through the second conductor 60.

In the cable pull-in nozzle 56, the first
An end of the conductor 59 is electrically coupled to a conductor 61 for supplying power to a motor installed in the submerged motor pump, and the second conductor 6 protruding toward the atmosphere side of the atmosphere side base 58.
The end portion of 0 is electrically connected to the lead wire on the power source side.

In this double seal connection terminal device, an inert gas such as nitrogen gas is press-fitted therein. A gas introduction device 64 having a pressure gauge 62 and an opening / closing valve 63 is connected to the intermediate pipe 52 of the double seal connection terminal device for press-fitting nitrogen gas.

This double-seal connection terminal device requires a very high degree of airtightness against the inert gas press-fitted into the intermediate pipe thereof, but the on-off valve does not have so much airtightness. Therefore, in order to achieve the high degree of airtightness, after the inert gas is press-fitted into the intermediate pipe by the gas introducing device, the joining portions of the respective parts of the gas introducing device are welded.

[0007]

Therefore, the gas introducing device has a serious problem that it cannot maintain the airtightness as it is, and in order to solve the problem, each part of the gas introducing device is There is a new problem that the complicated work of welding is required.

The present invention has been completed based on the above circumstances. It is an object of the present invention to provide a fluid introduction device having a high degree of airtightness or liquidtightness and having a simple structure, which does not require welding or the like. An object of the present invention is to allow a fluid to be contained in a container that should contain the fluid under pressure, in the air-tight or liquid-tight state, and to store the fluid in the container under pressure. Another object of the present invention is to provide a fluid introduction device that does not cause backflow or leakage of fluid even afterward.

[0009]

The invention according to claim 1 for solving the above-mentioned problems can be attached to a mounting hole provided in a container into which a fluid is introduced and having a communication hole communicating with the inside of the container. The formed plug body, a fluid introduction path that connects the outer opening portion that opens to the outside of the plug body and the peripheral surface opening portion that opens to the peripheral surface of the plug body, the inner peripheral surface of the communication hole, and the plug body. 3. The fluid introduction device according to claim 2, wherein the fluid introduction device is formed by the outer peripheral surface of the, and has a fluid flow passage that connects the peripheral surface opening portion and the communication hole.
A plug body that can be mounted in a mounting hole having a small diameter portion that communicates with the inside of a container body that contains a fluid and a large diameter portion that communicates from the small diameter portion to the outside, the plug body, and the outer surface of the plug body from the outside. A first seal member that is provided on the peripheral surface of the plug body so as to communicate with each other, and that seals the outer circumference and the large diameter portion of the plug body in an airtight or liquid-tight manner, and an outer peripheral surface of the plug body A fluid flow passage formed by the outer peripheral surface of the plug body and the inner peripheral surface of the large diameter portion so as to communicate with the opening of the fluid introduction path that is open to the small diameter portion, and provided at the bottom of the plug body, A fluid introduction device comprising a small diameter portion closing means for airtightly closing the small diameter portion and the fluid flow passage.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The fluid introducing device of the present invention serves as a gas introducing device when introducing gas as a fluid, and serves as a liquid introducing device when introducing liquid as a fluid.
Below, the example which applied the gas introduction apparatus to the double seal connection terminal device attached to a submerged motor pump is demonstrated. As shown in FIG. 1, the double seal connection terminal device 1 has a tubular body 2, a first conductor 3, a second conductor 4, and a gas introduction device 5.

The cylindrical body 2 has a cylindrical body 6 having both ends opened.
And a pump side flange portion 7 joined by welding to one end opening portion of the tubular body 6, and an atmosphere side flange portion 8 joined by welding to the other end opening portion of the tubular body 6.

The pump-side flange portion 7 is a thick-walled pump-side disc body 9 having a larger outer diameter than the outer diameter of the cylindrical body 6 so as to close the opening at one end of the cylindrical body 6. A pump-side cylindrical body 10 formed so as to project from one surface of the pump-side disk body 9 and joined by welding to an opening at one end of the cylinder body 6, and is provided so as to penetrate the pump-side disk body 9. The first conductor insertion hole 11 has a diameter into which the one conductor 3 can be inserted. Since the motor in the submerged motor pump is driven by three-phase alternating current, the number of the first conductor insertion holes 11 provided in the pump-side disc body 9 is three.

The pump-side flange portion 7 is further provided on the inner peripheral surface of the pump-side disk body 9 so that the plug body 12 which is a part of the gas introducing device 5 can be screwed onto the outer peripheral surface. Large-diameter portion 1 which is a substantially cylindrical space provided with a female screw
3 is opened, and at the bottom of the large diameter portion 13, the small diameter portion 1 that is a communication hole that communicates with the large diameter portion 13 and the inside of the cylindrical body 2.
The opening 4 is open.

The atmosphere-side flange portion 8 has an outer diameter larger than the outer diameter of the cylindrical body 6 so as to close the opening at the other end of the cylindrical body 6, and is on the atmosphere side (the cylindrical body 6 and the cylindrical body 6). A thick atmosphere-side disk body 16 having a disk-shaped recess 15 formed on the surface (on the opposite side), and the first conductor insertion hole 11 provided so as to penetrate the atmosphere-side disk body 16. A first opening which is opened so that the axes thereof coincide with each other and into which the second conductor 4 can be inserted.
The through hole 17, the atmosphere side cylindrical body 18 formed so as to project from one surface of the atmosphere side disk body 16 and joined to the other end opening of the cylinder body 6 by welding, and the recessed portion 15 can be mounted. And a disk body 20 having a second through hole 19 into which the second conductor 4 can be mounted. The diameter of the first through hole 17 is larger than that of the second through hole 19, and the second through hole 19 is designed to have a diameter into which the second conductor 4 can be fitted. The first through hole 17 and the second through hole 19 form the second conductor insertion hole in the present invention.
The number of the second conductor insertion holes is three, which is the same as the number of the first conductor insertion holes 11.

The first conductor 3 is formed by having a round rod-shaped body 21 made of copper and a cylindrical cylindrical ceramic body 22 formed on the outer peripheral surface thereof. The outer peripheral surface of the round rod-shaped body 21 and the inner peripheral surface of the ceramic cylindrical body 22 are integrally and closely formed.

The second conductor 4 has a structure similar to that of the first conductor 3, and has a copper round bar 21 and a ceramic cylindrical body 22.

One end of the first conductor 3 and one end of the second conductor 4 are formed so as to be electrically connectable to each other. In the embodiment shown in FIG. 1, the end portion of the round bar body in the second conductor 4 is formed. And the end portion of the first conductor 3 are coupled by screwing.

The first conductor 3 has a flange 7 on the pump side.
And are integrally connected as follows. That is, as shown in FIG. 2, an annular ring-shaped notch 24 provided around the first conductor insertion hole 11 provided on the pump-side surface of the pump-side disc body 9, that is, the surface facing the cable drawing nozzle 23. The outer peripheral surface of the ceramic tubular body 22 of the first conductor 3 fitted with the annular seal ring 27 having the annular inner wall surface 25 and the annular outer wall surface 26 and fitted into the first conductor insertion hole 11 and The inner wall surface 25 is brazed with silver (the silver brazing portion is shown by 28 in FIG. 2), and the outer wall surface 26 and the pump side surface of the pump side disc body 9 are silver brazed (silver in FIG. 2). The brazing portion is indicated by 29.), so that the first conductor 3 and the pump side flange portion 7 are provided.
And are combined and attached together. The silver brazing is performed on the outer circumference of the ceramic cylindrical body 22 of the first conductor 3 and the inner wall surface 2
5 is formed in an annular shape so as not to create a gap between the outer wall surface 26 and the pump-side disc body 9 and formed in an annular shape.

The second conductor 4 is integrally connected to the disk body 20 as follows. That is, the first through hole 1
The ring-shaped seal ring 27 having the ring-shaped inner wall surface 25 and the ring-shaped outer wall surface 26 is fitted into the ring-shaped recessed portion 15 provided around the opening of the ring member 7 on the side of the tubular body 6 to form the first through hole. The outer peripheral surface of the ceramic cylindrical body 22 of the second conductor 4 fitted in 17 and the inner wall surface 25 are silver brazed, and the outer wall surface 26 and the surface of the disc body on the cylinder body 6 side are silver brazed. As a result, the second conductor 4 and the disk body 20 are integrally connected,
Be attached. The silver brazing is formed in an annular shape so as not to create a gap between the outer periphery of the ceramic cylindrical body 22 of the second conductor 4 and the inner wall surface 25, and the outer wall surface 26 and the pump-side disc body 9 are connected to each other. It is formed in an annular shape so as not to create a gap in. The mounting state of the second conductor 4 on the disk body 20 is the same as that shown in FIG. 2, and can be understood by analogy with reference to FIG.

The gas introducing device 5 has a plug body 12. As shown in FIG. 3, the plug body 12 has a tip outer peripheral surface portion 30 which is a mere cylindrical outer peripheral surface without a male screw.
And a screw forming outer peripheral surface 31 having a male screw formed so as to be screwed with the female screw of the large-diameter portion 13, and a peripheral opening opening from the outer opening 32 opening to the rear end surface to the tip outer peripheral surface part 30. The gas introduction passage 34 formed to communicate with the portion 33, the peripheral surface opening 33 and the screw forming outer peripheral surface 31.
A first O-ring 35, which is a first seal ring, and a second O-ring 36, which is a small-diameter portion closing means, which is provided on the tip end surface of the plug body 12. To have. Further, the tip outer peripheral surface 30 has a large diameter portion 30a having an outer diameter that can be inserted into the large diameter portion 13, and a diameter from the peripheral surface opening 33 to the tip portion of the plug body 12 is larger than the large diameter portion 30a. With a small diameter portion 30b. Therefore, when the plug 12 is attached to the large diameter portion 13, the large diameter portion 1
A gap is formed between the inner peripheral surface of No. 3 and the outer peripheral surface of the small diameter portion 30b. This gap is the gas flow passage 37 which is the fluid flow passage in the present invention.

The double seal connection terminal device 1 is assembled, for example, as follows. The second conductor 4 is inserted into each of the three second through holes 19 of the disk body 20. An annular seal ring 27 is attached to the annular cutout portion 24 of the disc body 20. The disk body 20 and the outer wall surface 26 of the annular seal ring 27 are brazed with silver, and the inner wall surface 25 and the ceramic cylindrical body 22 are brazed with silver, so that each second through hole 1
The second conductor 4 is integrally and air-tightly coupled to 9. Then
The disk body 20 in which the three second conductors 4 are integrally connected is fitted into the recess 15. At this time, the second conductor 4 is inserted into each of the three first through holes 17 provided in the atmosphere-side disk body 16. The fitted disc body 20 is the disc body 16 on the atmosphere side.
Then, they are integrally connected by bolts from the side where the atmosphere side cylindrical body 18 is provided. Further, the annular joint portion 20A between the disc body 20 and the concave portion 15 is integrally joined by welding and hermetically sealed. Then, the annular end of the cylinder is abutted against the annular end of the atmosphere-side cylindrical body 18, and the abutting portion is welded so as to go around the outer circumference of the tubular body 6 to hermetically seal the abutting portion, Moreover, the cylinder body 6 and the atmosphere side cylinder body 18 are integrally connected.

Next, the end of the first conductor 3 is screwed into the end of the second conductor 4 existing in the tubular body 6 to mechanically and electrically connect the first conductor 3 and the second conductor 4. Unify. At this time, the three first conductors 3 are in a state of protruding from the one end opening of the cylindrical body 6.

The tips of the three first conductors 3 are inserted into the first conductor insertion holes 11 in the pump side flange portion 7. After insertion, the pump side cylindrical body 1 in the pump side flange portion 7
The annular end portion of 0 and the annular end portion of the tubular body 6 are abutted, and the abutting portion is welded so as to go around the outer circumference of the tubular body 6 to hermetically seal the abutting portion, and the tubular body 6 And the pump-side cylindrical body 10 are integrally connected.

Annular notch 2 in the disc 20 on the pump side
The annular seal ring 27 is attached to the No. 4. The pump-side disc body 20 and the outer wall surface 26 of the annular seal ring 27 are brazed with silver, and the inner wall surface 25 and the ceramic tubular body 22 are brazed with silver, whereby the second conductor is inserted into the insertion hole 11 for the first conductor. 4 are joined together and airtightly.

The plug 12 is screwed into the large diameter portion 13. However, the tip end surface of the plug body 12 should not be in close contact with the bottom surface of the large diameter portion 13. As a result, as shown in FIG. 3, the gap between the outer peripheral surface of the small-diameter portion 30b of the plug body 12 and the inner peripheral surface of the large-diameter portion 13 and the tip surface of the plug body 12 and the bottom surface of the large-diameter portion 13 are formed. A gas flow passage 37 is formed by the gap.

Therefore, a gas introduction nozzle of a gas supply device (not shown) is connected to the outer opening 32 of the plug 12, and an inert gas such as nitrogen gas is passed through the gas introduction passage 34, the gas flow passage 37 and the small diameter portion 14. , Press-fit into the cylindrical body 2. At this time, since the first O-ring 35 is attached to the plug body 12, the nitrogen gas does not leak to the outside from the gap between the inner peripheral surface of the large diameter portion 13 and the outer peripheral surface of the plug body 12. After nitrogen gas is press-fitted into the cylindrical body 2 to reach a predetermined pressure, the plug 12 is further screwed until the tip surface of the plug 12 reaches the bottom of the large diameter portion 13. As shown in FIG. 4, in the state in which the screwing is completed, the second O-ring 36 is in close contact with the bottom of the large-diameter portion 13, and therefore the first O-ring 35 and the second O-ring 35 are attached. With 36, the nitrogen gas press-fitted into the cylindrical body 2 does not leak outside. Therefore, the gas introduction nozzle is connected to the outer opening 3 of the plug body 12.
Remove from 2. Then, the mating portion of the plug body 12 and the large diameter portion 13 is sealed by welding.

Thus, the double seal connection terminal device 1 is completed.

The dull seal connecting terminal device 1 according to this aspect has a structure that does not include a gasket itself. Moreover, when the double seal connection terminal device 1 is connected to the cable drawing nozzle 23, as shown in FIG. 1, the flange 23A and the pump side flange 7 of the cable drawing nozzle 23 are connected to the gasket 23B.
And the flange portion 23A of the cable drawing nozzle 23 and the pump-side flange portion 7 are integrally connected with each other by bolts. Therefore, when the double seal connection terminal 1 in this mode is connected to the cable drawing nozzle 23 of the submerged motor pump, the possibility that high-pressure gas on the submerged motor pump side leaks becomes extremely small.

The structure of the conventional double seal connecting terminal device shown in FIG. 9 is compared with the structure of the double seal connecting terminal device which is an example of the present invention. Since there is no atmosphere side base, the number of parts is reduced by that much, and a gasket for connecting the flange of the intermediate pipe and the flange of the pump side base and a gasket for connecting the flange of the intermediate pipe and the flange of the atmosphere side base. Since it is unnecessary, the number of parts also decreases in this respect, and since such a gasket is not used,
The double-seal connection terminal device as an example of the present invention has a very low possibility of leakage of high-pressure gas, and is a highly reliable double-seal connection terminal device.

Moreover, the double seal connection terminal device as an example of the present invention has a simple structure with a small number of parts, and is therefore easy to manufacture and easy to disassemble for maintenance and inspection.

Since the double seal connection terminal device 1 according to one embodiment of the present invention has the gas introducing device 5 having the plug 12 as shown in FIG. In comparison, the inert gas can be press-fitted into the cylindrical body 2 in an airtight manner, and the inert gas can be prevented from leaking outside after the press-fitting.

Although one aspect of the present invention has been described above, the double seal connection terminal device of the present invention is not limited to the above aspect.

The cylindrical body in the present invention is not limited to the cylindrical body 6 interposed between the pump side flange portion 7 and the atmosphere side flange portion 8 as shown in FIG. The pump side cylindrical body 10 in the portion 7 is extended to a predetermined length, and the atmosphere side cylindrical body 18 in the atmosphere side flange portion 8 is extended to a predetermined length.
It may be configured by a cylinder body formed by abutting 0 and the atmosphere side cylinder body 18.

The cylindrical body 2, the pump-side flange portion 7 and the atmosphere-side flange portion 8 in the present invention can hermetically seal an inert gas inside, and the first conductor 3 and the second conductor 4 respectively. Has a function as a case that can be airtightly attached. The pump side flange 7 is the first
It has a function of air-tightly and integrally connecting the conductors 3 to support them. The atmosphere-side flange portion 8 has a function of airtightly and integrally connecting the second conductor 4 and supporting the same. The cylindrical body 2, the pump-side flange portion 7 and the atmosphere-side flange portion 8 may have any configuration as long as they have such a function.

The gas introduction device 5 is not limited to the embodiment shown in FIG. The gas introduction device 5 includes a gas flow passage 37 that allows the gas introduction passage 34 to communicate with the small diameter portion 14,
A plug that can hermetically seal the outer peripheral surface of the plug 12 and the inner peripheral surface of the large-diameter portion 13, and can hermetically seal the outer opening 32 of the small-diameter portion 14 that opens to the large-diameter portion 13. Body 1
As long as it has 2, it can have various structures.

For example, the gas introducing device 5 according to the present invention may be the gas introducing device 5 provided with the plug 12 having the following structure. The plug body 12 shown in FIGS. 5 and 6 includes a tip outer peripheral surface portion 38 which is a simple outer peripheral surface of a cylinder without a male screw, and a male screw formed so as to be screwed with the female screw of the large diameter portion 13. Screw forming outer peripheral surface portion 3 having
9, a gas introduction passage 34 formed so as to communicate from the outer opening 32 opening to the rear end surface to the peripheral surface opening 33 opening to the tip outer peripheral surface portion 38, and the peripheral surface outer opening 3
And a first O-ring 35, which is a first seal ring, provided on the outer peripheral surface between the screw forming outer peripheral surface portion 39 and the screw forming outer peripheral surface portion 39.
It has a second O-ring 36, which is a small-diameter portion closing means provided on the tip end surface of the plug body 12. Further, the large-diameter portion 13 has an enlarged large-diameter portion 40 provided on the inner peripheral surface of the large-diameter portion 13 within the range in which the outer peripheral surface of the tip of the plug 12 moves. The gap formed between the peripheral surface and the outer peripheral surface of the tip of the plug 12 is the gas flow passage 37 in the present invention. In this plug body 12, as shown in FIG. 3, it is not necessary to process the portion having the outer peripheral surface of the tip of the plug body 12 into a diameter smaller than the diameter of the plug body 12.

When the bottom of the large-diameter portion 13 is formed in a conical shape as shown in FIGS. 7 and 8, for example, instead of the plug 12 as shown in FIG. Instead of using the O-ring 36, the gas introduction device 5 having the plug body 12 having a conical tip portion may be used.

The small-diameter portion closing means for closing the opening portion of the small-diameter portion between the bottom portion of the large-diameter portion and the bottom portion of the plug body may be a packing provided at the tip of the plug body. The small-diameter portion closing means can employ various configurations as long as it has a function of effectively closing the opening portion of the small-diameter portion. The liquid introducing device can also be configured with the same structure as this gas introducing device.

[0039]

According to the present invention, it is possible to provide a fluid introduction device (gas introduction device, liquid introduction device) having a high degree of air-tightness or liquid-tightness and having a simple structure without requiring welding or the like. it can. According to the present invention, a fluid that can be stored under pressure can be stored in the container in a gas-tight or liquid-tight state, and after the fluid is stored under pressure in the container. Also in the above, it is possible to provide a fluid introduction device that does not cause backflow or leakage of fluid.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a double seal connection terminal device including a gas introduction device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which a first conductor is coupled to a pump-side disc body.

FIG. 3 is a cross-sectional view showing a plug body in the gas introduction device 5.

FIG. 4 is a sectional view showing an operation of the plug body.

FIG. 5 is a cross-sectional view showing a plug body which is another mode of the gas introduction device 5.

FIG. 6 is a cross-sectional view showing the operation of the plug body shown in FIG.

FIG. 7 is a cross-sectional view showing a plug body which is another mode of the gas introduction device 5.

FIG. 8 is a cross-sectional view showing the operation of the plug body shown in FIG.

FIG. 9 is a cross-sectional view showing a conventional double seal connection terminal device having an opening / closing valve.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Double seal connection terminal device, 2 ... Cylindrical body, 3 ... 1st conductor, 4 ... 2nd conductor, 5 ... Gas introduction device 5, 6 ... Cylindrical body, 7 ... Pump-side flange portion, 8 ... Atmosphere-side flange portion, 9 ... Pump-side disk body, 10 ... Pump-side cylindrical body, 11 ... First conductor insertion hole, 12 ...・ Stoppers, 13 ... Large diameter part, 14 ・
..Small diameter part, 15 ... Recessed part, 16 ... Atmosphere side disk body, 17 ... First through hole, 18 ... Atmosphere side cylinder body,
19 ... second through hole, 20 ... disk body, 21 ...
Round bar, 22 ... Ceramic tube, 23 ...
Cable drawing nozzle, 24 ... Annular notch, 25
... Inner wall surface, 26 ... Outer wall surface, 27 ... Annular seal ring, 28 ... Silver brazing portion, 29 ... Silver brazing portion, 30 ... Tip outer peripheral surface portion, 30a ...・ Large diameter part, 30b ... Small diameter part, 31 ... Screw forming outer peripheral surface, 32 ... Opening part, 33 ... Peripheral surface opening part, 34 ...
..Gas introduction path, 35 ... First O-ring, 36 ...
-Second O-ring, 37 ... Gas flow passage.

Claims (2)

[Claims] 1. A plug body which is provided in a container into which a fluid is introduced and is formed so as to be attachable to a mounting hole having a communication hole communicating with the inside of the container, and an outer opening and a plug which are open to the outside of the plug body. A fluid introduction path that connects the peripheral surface opening that opens to the peripheral surface of the body, an inner peripheral surface of the communication hole, and an outer peripheral surface of the plug, and connects the peripheral surface opening and the communication hole. And a fluid flow passage that operates. 2. A plug body mountable in a mounting hole having a small diameter portion communicating with the inside of a container body for containing a fluid and a large diameter portion communicating with the outside from the small diameter portion, and the plug body, which is externally plugged. A fluid introduction path provided so as to communicate with the peripheral surface of the body,
A first seal member provided on the peripheral surface of the plug body for airtightly or liquid-tightly closing the outer periphery and the large diameter portion of the plug body, an opening of a fluid introduction passage opening to the outer peripheral surface of the plug body, and the small diameter portion. Fluid passage formed by the outer peripheral surface of the stopper and the inner peripheral surface of the large diameter portion so as to communicate with, and provided in the lower portion of the stopper to hermetically close the small diameter portion and the fluid passage. A fluid introduction device having a small diameter portion closing means.