JP3026402B2 - Air valve seal structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal structure for an air valve used in a sewage pipe or the like.

[0002]

2. Description of the Related Art Conventionally, air valves disposed in sewage pipes and the like are:
For example, the structure is as shown in FIGS. 3 and 4, the valve box 1 communicates with a pipe to be mounted at the bottom, and an air hole cover 3 forming a large air hole 2 for discharging air is provided at the top of the valve box 1. An exhaust port 4 is provided at a rising portion of the hole cover 3.

A valve body 5 for opening and closing the large air hole 2 is disposed inside the valve box 1, and a shaft 6 of the valve body 5 is connected to the air hole cover 3.
And is supported by a diaphragm 7 arranged above. The diaphragm 7 is provided between the spring box 8 provided above the air hole cover 3 and the pressure chamber cover 9. A spring 10 for urging the diaphragm 7 upward is disposed inside the spring box 8.
Forms a pressure chamber 9a with the diaphragm 7.
The pressure chamber cover 9 is provided with a pressure adjusting plug 9b. A small air hole 11 is formed in the lower part of the valve body 5,
Reference numeral 1 communicates with the pressure chamber 9a through a through hole 12 provided in the shaft portion 6 of the valve body 5.

[0004] The float 13 disposed inside the valve box 1 has a float shaft 13a, and the float shaft 13a penetrates through a splash removing portion 14 disposed in the upper space of the valve box 1. The float shaft 13a has a slot 13b at the upper end, and the slot 13b
The float shaft 13a is connected to the valve body 5 through the pin 15 inserted through the valve body 5.
It is connected to the lower part. For this reason, the float 13 moves up and down with respect to the valve element 5 within a range allowed in the long hole 13b, and closes the small air hole 11 at the upper point. The splash guard 14 has a ventilation hole 16, and a strainer 17 is arranged in the ventilation hole 16.

According to this configuration, in the closed state, the valve element 5 closes the large air hole 2 and the float shaft 13a closes the small air hole 11. In this closed state, when air accumulates in the internal space of the valve box 1 and the water level in the valve box 1 decreases, the internal pressure of the valve box 1 causes the valve body 5 to close the large air hole 2 and the water level decreases. Accordingly, the float 13 descends within a range allowed in the long hole 13b, and opens the small air hole 11.

In this state, the air inside the valve box 1 is
1 to the pressure chamber 9a through the through hole 12 and flows out through the pressure adjusting plug 9b. On the other hand, the difference between the inflow amount and the outflow amount of air in the pressure chamber 9a acts on the diaphragm 7 as residual pressure, and this force pushes down the valve body 5 via the shaft 6 to open the large air hole 2.

In the open state where the large air hole 2 is opened,
A large amount of air in the valve box 1 is the strainer 1
7, from the large air hole 2 to the inside of the air hole cover 13,
The air is exhausted to the outside through the exhaust port 4.

When the water level in the valve box 1 rises with the exhaust of air, the float 13 rises due to buoyancy, and the float shaft 13a closes the small air hole 11. When the small air hole 11 is closed, the supply of air to the pressure chamber 9a is stopped, the pushing force of the diaphragm 9 is lost, and the pushing force of the spring 10 and the buoyancy of the float 13 push up the valve body 5, and the valve body 5
Returns to the closed state in which the large air hole 2 is closed.

[0009]

However, in the above-described conventional structure, foreign matter in the fluid is removed by the strainer 17 at the time of exhaust, but minute foreign matter passes through the strainer 17 and passes through the small air hole 11. The pressure chamber 9a may reach the pressure chamber 9a through the through hole 12. When the minute foreign matter is clogged in the pressure adjusting plug 9b, it is difficult or impossible to eliminate the pressure in the pressure chamber 9a. When the valve body 5 is pushed up by the rise of the float when closing, the pressure chamber 9a
The pressure remaining in the valve body 5 hinders the closing movement of the valve element 5. For this reason,
The closing operation of the valve body 5 with respect to the large air hole 2 is delayed,
There is a problem that the fluid flows out from the outside.

[0010] The present invention solves the above-mentioned problems, and it is difficult or impossible to eliminate the pressure in the pressure chamber due to clogging of the pressure adjusting plug, and even if the closing operation of the valve body is delayed, the fluid is not removed. It is an object of the present invention to provide a seal structure of an air valve in which no air flows out.

[0011]

In order to solve the above-mentioned problems, a seal structure for an air valve according to the present invention comprises a valve body for opening and closing a large air hole inside a valve box having a large air hole in an upper part. Arranged freely, the valve body is supported by a diaphragm provided above the valve box, and the float shaft of the float placed inside the valve box is connected to the lower part of the valve body so that it can move up and down over a certain distance, and the float is attached to the valve body. An air valve that forms a small air hole that opens and closes with the float shaft by the up and down movement of the float shaft, connects the small air hole to the pressure chamber formed on the back of the diaphragm, and connects the pressure chamber to the atmosphere through the pressure adjustment plug A splash-repelling part for vertically partitioning the internal space of the valve box in the valve box is provided by loosely fitting to the float shaft, and a vent hole is formed in the splash-repelling part to open around the float shaft, and a lower surface side of the splash-repellent part is provided. Place the bellows body The bellows body is loosely fitted and fixed to the float shaft at the lower end, and a sealing means is provided at the upper end side of the bellows body to open and close the vent hole around the opening of the bellows body. It has a configuration in which holes are formed.

[0012]

With the above construction, in the closed state, the valve plug closes the large air hole, the float shaft closes the small air hole, and the bellows shrinks, and the folds come into close contact with each other to close the small hole. At the same time, the bellows body presses the sealing means against the lower surface of the splash eliminator to close the ventilation hole.

In this closed state, when air accumulates in the internal space of the valve box and the water level in the valve box decreases, the float descends with the decrease in the water level, and the bellows body extends. At this time, the sealing means receives the air pressure in the valve box and the elastic force of the bellows body that cannot be completely extended, and presses against the lower surface of the splash-repellent portion to close the ventilation hole around the opening of the bellows body. When the bellows body is extended and the small hole of the fold is opened, the air in the valve box below the splashing portion flows from the small hole through the inside of the bellows body and the ventilation hole of the splashing portion to the bottom of the valve body. It flows into the space, and the valve body is maintained in a state of closing the large air hole by the air pressure in the valve box.

Further, when the water level in the valve box decreases and the float loses buoyancy, the float and the float shaft further descend within an allowable range to open a small air hole of the valve body, and seal with the extended bellows body. The means descends to open the vent. At this time, since the small holes of the bellows body have already been opened, the air pressures in the valve boxes on both sides bordering the sealing means have become equal, and the sealing means descends smoothly.

By opening the small air hole, the air in the valve box reaches the pressure chamber from the small air hole and flows out to the atmosphere through the pressure adjusting plug. On the other hand, the difference between the inflow and outflow of air in the pressure chamber acts on the diaphragm as residual pressure, and this force pushes down the valve body to open the large air hole. In the open state where the large air hole is opened, a large amount of air in the valve box is exhausted to the outside from the large air hole through the ventilation hole of the splashing portion.

When the water level in the valve box rises with the exhaust of air, the float and the float shaft rise due to buoyancy,
Sealing means located on the upper end side of the bellows body that has been fully extended closes the ventilation hole of the splashing portion.

Further, when the water level in the valve box rises, the float and the float shaft rise while contracting the bellows body,
The float shaft closes the small air hole and stops the supply of air to the pressure chamber, eliminating the pushing force of the diaphragm, the buoyancy of the float pushes up the valve body, and the valve body closes the large air hole. Return to.

Therefore, before the large air hole is closed by the valve element, the sealing means closes the air hole of the splashing portion, so that the pressure regulating plug is closed, and the pressure chamber is closed when the valve element is closed. Even when the pressure does not escape and the pressing force of the diaphragm hinders the closing movement of the valve body, the fluid in the valve box can be prevented from flowing out to the outside by the sealing means.

[0019]

An embodiment of the present invention will be described below with reference to the drawings. 1 and 2, the configuration of the diaphragm described above with reference to FIGS. 3 and 4 is omitted.
Further, members performing the same operation are denoted by the same reference numerals, and description thereof is omitted.

In FIG. 1 and FIG.
A splash protector 21 for partitioning the internal space of the valve box 1 up and down is provided so as to be loosely fitted on the float shaft 13a, and the splash protector 21 has a vent hole 22 opened around the float shaft 13a.
Is formed.

The float shaft 1 is provided on the lower surface of the
The bellows body 23 is arranged so as to be loosely fitted to the bellows body 3a.
The lower end of 3 is fixed to the float shaft 13a. The bellows body 23 has a plurality of folds 23a, and the corresponding folds 23a are provided with small holes 23b, respectively. Further, the bellows body 23 is made of a resin material or a rubber material, and is in an extended state as usual.

A large diaphragm 24 serving as a sealing means connected to the upper end side of the bellows body 23 is disposed. The large diaphragm 24 is located on the lower surface side of the splash-repellent portion 21 and is fixed to the valve box 1 at the peripheral edge. ing. The large diaphragm 24
An annular portion 24a located at a peripheral portion and having an arc-shaped cross section, a small ventilation hole 24b formed in the annular portion 24a, and an annular portion 24a
And a seal portion 24d having a diameter larger than that of the vent hole 22 of the splash-removal portion 21 and surrounding the opening of the bellows body 23, and having a ring shape. The large diaphragm 24 opens and closes the vent hole 22 around the opening of the bellows body 23 by contacting the lower surface of the splash protector 21.

The operation of the above configuration will be described below.
In the closed state, the valve element 5 closes the large air hole 2, the float shaft 13 a closes the small air hole 11 of the valve element 5, and the bellows 2
3 contracts and the folds 23a come into substantial contact with each other so that the small holes 2
3b is closed, the bellows 23 presses the large diaphragm 24 against the lower surface of the splashing portion 21, and the seal portion 24d
The air hole 22 is closed by abutting on the lower surface of the splash-repellent portion 21 around 2.

In this closed state, when air accumulates in the internal space of the valve box 1 and the water level in the valve box 1 decreases, the float 13 descends with the decrease in the water level, and the bellows body 23 extends. At this time, the large diaphragm 24 receives the air pressure in the valve box 1 and the elastic force of the bellows body 23 that does not completely expand, and presses against the lower surface of the splash elimination part 21 to close the ventilation hole 22 around the opening of the bellows body 23. In state. When the bellows body 23 is extended and the folds 23a are separated from each other and the small holes 23b are opened, the air in the valve box 1 below the splash preventing portion 21 is removed from the small holes 2a.
3b flows into the lower space of the valve body 5 through the inside of the bellows body 23 and the ventilation hole 22 of the splash elimination part 21, and the valve body 5 is maintained in a state where the large air hole 2 is closed by the air pressure in the valve box 1. Is done.

Further, when the water level in the valve box 1 decreases and the float 13 loses buoyancy, the float 13 and the float shaft 1
3a further descends within the permissible range in the long hole 13b to open the small air hole 11 of the valve body 5, and the flat portion 24c of the large diaphragm 24 descends together with the bellows 23 which has been fully extended. The lowering of the flat plate portion 24c is permitted by the extension of the annular portion 24a, and the vent hole 22 is opened by the lowering of the flat plate portion 24c. At this time, since the small holes 23b of the bellows body 23 have already been opened, the air pressures in the valve boxes 1 on both sides bordering the large diaphragm 24 have become equal, and the large diaphragm 24
Descends smoothly.

When the small air hole 11 is opened, the air in the valve box 1 passes from the small air hole 11 through the through hole 12 to the pressure chamber 9a.
And flows out to the atmosphere through the pressure adjusting plug 9b. On the other hand, the difference between the inflow and outflow of air in the pressure chamber 9a acts on the diaphragm 9 as residual pressure, and this force pushes down the valve body 5 to open the large air hole 2. In the open state in which the large air hole 2 is opened, the air in the valve box 1 flows through the plurality of small air holes 24 b of the large diaphragm 24 and the splashing portion 21.
And a large amount of air is exhausted from the large air hole 2 to the outside through the ventilation hole 22.

When the water level in the valve box 1 rises as the air is exhausted, the float 13 and the float shaft 13 receive buoyancy.
The large diaphragm 24 located on the upper end side of the bellows body 23 which has risen and has been fully extended has the sealing portion 24d to prevent the splashing portion 2
The air hole 22 is closed by abutting on the lower surface of the first.

Further, when the water level in the valve box 1 rises, the float 13 and the float shaft 13a rise while contracting the bellows body 23, and the float shaft 13a closes the small air hole 11 and air to the pressure chamber 9a. Is stopped, the pushing force of the diaphragm 9 is eliminated. For this reason, the buoyancy of the float 13 and the elastic force of the spring 10 push up the valve element 5, and the valve element 5 returns to the closed state in which the large air hole 2 is closed.

As described above, before the large air hole 2 is closed by the valve element 5, the large diaphragm 24 is
The pressure regulating plug 9b is closed by foreign matter or the like, the pressure in the pressure chamber 9a does not escape when the valve body 5 is closed, and the pushing force of the diaphragm 9 causes the pressure drop of the valve body 5 to close. Even in the case where the closing movement is inhibited, the large diaphragm 24 can prevent the fluid in the valve box 1 from flowing out.

[0030]

As described above, according to the present invention, before closing the valve body, the ventilation hole of the splash elimination part is closed by the sealing means, so that the closing of the valve body due to malfunction of the pressure regulating plug. Does not flow out of the valve box to the outside.

[Brief description of the drawings]

FIG. 1 is a sectional view of an air valve showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing expansion and contraction of a bellows body in the embodiment.

FIG. 3 is a cross-sectional view showing a main part of a conventional air valve.

FIG. 4 is an overall sectional view of the air valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve box 2 Large air hole 5 Valve body 11 Small air hole 13 Float 13a Float shaft 21 Splash prevention part 22 Vent hole 23 Bellows body 23a Folding part 23b Small hole 24 Large diaphragm

Claims (1)

(57) [Claims] 1. Inside a valve box having a large air hole in the upper part,
The valve body that opens and closes the large air hole is arranged to be able to move up and down, the valve body is supported by the diaphragm provided above the valve box, and the float axis of the float placed in the valve box is moved up and down a fixed distance below the valve body. It is movably connected, a small air hole is formed in the valve body that opens and closes with the float shaft by the vertical movement of the float, and the small air hole communicates with the pressure chamber formed on the back of the diaphragm. In the air valve which is communicated with the atmosphere through the air filter, a splash guard portion is provided in the valve housing for partitioning the internal space of the valve housing up and down, which is loosely fitted to the float shaft, and a vent hole opened around the float shaft in the splash guard portion. The bellows body arranged on the lower surface side of the splash elimination part is loosely fitted to the float shaft, and is fixed to the float shaft at the lower end, and a ventilation hole is formed around the opening of the bellows body at the upper end side of the bellows body. Open and close Le means is provided, the sealing structure of the air valve, characterized in that the formation of the small holes in the corresponding contact fold portion of the bellows body.