JPS5927587Y2 - quick exhaust valve - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement in an exhaust valve for automatically removing air from a water pipe.

Generally, air bubbles (hereinafter referred to as air) are present in water pipes when air mixed in from a water source or air dissolved in water is separated.

On the other hand, since water pipes are laid undulating up and down due to the topography, structures, etc., the above-mentioned air tends to stay in the sloped convex parts of the water pipes, reducing the water flow cross section of the water pipes. This causes problems such as the air lock phenomenon that occurs when air is compressed and expanded by water pressure, and the air hammer phenomenon that occurs when air is compressed and expanded by water pressure.

These phenomena also occur during water supply, and are particularly noticeable when submerged in water.

In order to avoid such a phenomenon, conventionally, an exhaust valve for removing air has been provided at the convex part of the gradient in the water supply pipe.

As shown in Fig. 1, a conventional exhaust valve houses a float valve 3 inside a valve body 1 having an exhaust hole 2 at its upper end, and the exhaust hole is opened by vertical movement of the float valve 3 as the water level rises and falls inside the valve body. 2
Due to its structure, the cross section of the exhaust hole 2 cannot be made large, and therefore the exhaust speed is extremely low.

That is, in the conventional exhaust valve, the cross-sectional area of the exhaust hole 2 is A, the weight of the float is W, and the buoyancy of the float due to water is F.
, when the pipe internal pressure is P, when air accumulates in the valve body 1, in order for the float valve 3 to fall and the exhaust hole 2 to open, W>PA... (1) In order for the float valve 3 to close the exhaust hole 2 when the air escapes and water rises into the valve body 1, it is necessary to ...(2) It is necessary to do so.

Combining equations 1 and 2, we get F＞W＞PA・・・・・・・・・(3) The following relationship is obtained.

From Equation 3, it can be seen that if the cross-sectional area A of the exhaust hole is increased in order to increase the exhaust speed, a float valve with larger weight and volume will be required.

Such exhaust valves are not practical, and in reality, only small exhaust valves with a diameter of about 100 myin are used, and the float valve has a mathematical diameter of about 100 myin.

However, unlike urban water supply and sewage systems, water transmission pipes for agricultural water such as field irrigation facilities have many ups and downs due to the highly undulating terrain, and are not used continuously, but intermittently, and have periods of idleness. Because water escapes inside the case,
Each time it is used, it must be submerged in water, which imposes harsh conditions both geographically and operationally.

Particularly in cases of flooding, even if exhaust valves are installed at various locations, if water is supplied in excess of the exhaust capacity of the exhaust valves, air locks and air hammer phenomena may occur. In addition, there is an inconvenience in that it is difficult to entrust the operation of the facility to agricultural workers, who are the users of the water pipes, because it requires specialized knowledge and skill in hydraulic technology.

Therefore, it has been desired to develop a rapid exhaust valve that can completely remove the air in the water pipe in a short period of time.

This invention improves the above-mentioned drawbacks of conventional exhaust valves, and is applicable to agricultural water pipes, and is a rapid exhaust valve that can completely remove air in a short period of time during water weiring and water supply. This is what we intend to provide.

However, the gist of the present invention is that it has a main valve that opens and closes an exhaust hole in a valve body, and a float valve that opens and closes a pilot hole provided in the main valve, and that the main valve is located at the top of a chamber that is fixed in the body. The rapid exhaust valve is supported by a diaphragm that receives pressure from both the inner and outer surfaces of the chamber, and the float valve is housed in the chamber and has a water passage hole at the bottom of the chamber. .

The present invention will be explained below with reference to figures.

Fig. 2 is a longitudinal sectional view showing one embodiment of the present invention, Fig. 3 is a sectional view taken along line AA' in Fig. 2, and Fig. 4 is a partial longitudinal sectional view showing the state in which the rapid exhaust valve of the present invention is attached to a water pipe. A top view and FIG. 5 are longitudinal sectional views showing the main valve of FIG. 2 in an open state.

An exhaust hole 5 having a relatively large cross section is provided at the top of the valve body 4.
is provided, and the lower end is open so as to communicate with the water pipe 113.

A chamber 6 is housed inside the valve body 4 and is fixed to the valve body 4 by a support 7.

The top of the chamber 7 is sealed by a diaphragm 8 with a main valve 9 mounted in the center.

A suitable material for the flexible diaphragm is normally a fiber-reinforced rubber sheet, and in order to ensure that the valve can be opened and closed, it is desirable that its cross-sectional area be sufficiently large.

The main valve 9 is usually made of a material with some weight, such as gunmetal.
It has a pilot hole 10 with a small cross section in the center, and is supported by a flexible diaphragm 8 so that it can move up and down, thereby opening and closing the exhaust hole 5.

Since the pilot hole 10 is for removing a small amount of air from the chamber 6, it may be as small as a conventional exhaust hole.

Further, a water hole 12 is provided at the bottom of the chamber 6, through which water enters and exits the chamber 6, giving rise and fall to the float valve 3 as the water level rises and falls. The pilot hole 10 is opened and closed.

In the embodiment shown in FIG. 2, the float valve 3 is guided by four float guides 11 so as to properly abut the valve seat 20 of the pilot hole 10.

The quick exhaust valve 15 of the present invention thus constructed is normally connected to the upper end of a branch pipe 14 provided in the water pipe 13, as shown in FIG.

The exhaust action of the quick exhaust valve of the present invention will be explained below.

Figure 2 shows water entering the exhaust valve of the present invention and the float valve 3.
The figure shows a state in which the main valve 9 is pushed up by the buoyant force and the exhaust hole 5 is closed.

When air 16 enters the water pipe 13, the air 16 is light, so it enters the valve body 4 of the rapid exhaust valve 15 through the diameter of the branch pipe 14, floats up, collects at the top of the valve body, and increases its volume. The water level 17 in the valve body decreases by that amount.

As the amount of air entering the valve body 4 increases, the water level 17 in the valve body further decreases, and finally reaches the water passage hole 12 as shown in FIG.
Down below, the water passage hole 12 communicates with the air 19 within the valve body, so that the water within the chamber 6 drains and is replaced by the air 19 within the valve body.

When the water in the chamber 6 is discharged from the water passage hole 12, the water level 18 in the chamber falls, and when the buoyancy is lost, it falls by the force of the float valve 3, so the pilot hole 10 opens and the chamber 6 opens to the atmosphere, reducing the internal pressure. However, due to the pressure difference between the inside and outside of the diaphragm 8, the main valve 9 is pushed down and the exhaust hole 5 is opened.

The opening and closing action of the valve will be explained in more detail below.

Now P: Pressure inside the valve body (atmospheric pressure standard) Pl: Pressure inside the chamber (atmospheric pressure standard) A: Exhaust hole 5
Horizontal cross-sectional area B: Effective area of diaphragm 8 C: Horizontal cross-sectional area of pilot hole 10 divided by double water hole 1
2 horizontal cross-sectional area W: weight of float valve 3 F: buoyancy of float valve 3, in order for float valve 3 to open and close, it must be designed so that F>W>CP. is similar to a conventional exhaust valve.

Next, when the float valve 3 is lowered and the pilot hole 10 is opened, if the pressure P1 inside the chamber 6 drops to atmospheric pressure, the force FD applied to the flexible diaphragm 8 at this time is FD = (B-A) P・・・・・・・・・(4),
It works downward to open the exhaust hole 5.

On the other hand, if the pressure inside the chamber falls to atmospheric pressure and at the same time air flows in from the water passage hole 12, the pressure P1 inside the chamber increases, and P>PI>0.

At this time, the pressure applied to the diaphragm 8 is the downward force f
d, and if the pushing force is fu, then f d=(B A
) (P Pt )fu-(AC)Pl Therefore, the resultant force FD of both is FD = f d fu (B-A) (P-P□)-(A-C)PI(B
A) P (B-C) PI (5).

In order for the flexible diaphragm 8 to move downward, it is sufficient to satisfy FD>0 - (B A) P (B C) Pt>0.

By the way, if B is set sufficiently large, B-C=1 and B-A' can be obtained even if there is a considerable difference between C and A, and if D is set appropriately small, water flow from the water hole 12 to the chamber can be achieved. The air or water flowing into 6 is depressurized by the throttling effect and becomes >1, so Equation 6 can be satisfied.

Therefore, it is preferable that the cross section of the water passage hole 12 be as small as possible to the extent that the water in the chamber 6 can be discharged while replacing it with air when the pilot hole 10 is closed.

In addition, the cross section of the water passage hole 12 is further reduced to provide a pinhole-sized hole in the upper part of the chamber 6 or the part where the outer surface of the diaphragm 8 is in contact with the air, and air is allowed to flow in through this small hole. You may drain the water inside.

As described above, even if air flows into the chamber 6 from the water passage hole 12, the exhaust hole 5 can be opened as shown in FIG.

When the exhaust hole 5 opens, the air 19 inside the valve body flows out, so
The air P2 directly above the diaphragm 8 is depressurized, and P1>P2>0 holds true.

Therefore, for the flexible diaphragm 8, f u = (B - C)
Although an upward force (PI P2 ) acts, a large amount of air is discharged at the same time as the exhaust hole 5 is opened, so the water level 17 in the valve body quickly rises above the water passage hole 12, and the water level 17 in the valve body quickly rises above the water passage hole 12. , the flow of air into the chamber 6 is stopped, and only water with high resistance can flow in, so Pl becomes P
Although it is slightly larger than 2, it becomes a value very close to P2, and Pl-P2f:O,'',fu book O holds true.

Due to this relationship and the effect of the weight of the main valve 9 made of gun metal or the like, the main valve 9 is safely maintained in the open state.

Further, the main valve 9 may be stabilized using a spring.

Furthermore, air continues to be discharged from the exhaust valve 5, and the water level of the valve body decreases to 1.
7 rises and exceeds the water level 18 in the chamber, the water level 18 in the chamber also rises, and the float 3 rises to block the pilot hole 10 and further pushes up the main valve 9 to block the discharge hole 5. This will stop air exhaust.

When air enters the valve body 4 again, the rapid exhaust valve repeats the above operation.

As described above, the present invention uses the action of a float valve to open a pilot hole with a small cross section, depressurizes the air in the chamber, and uses the differential pressure between the inside and outside of a diaphragm with a large area to open an exhaust hole with a large cross section. , even if the valve body is the same as a conventional exhaust valve, the cross section of the exhaust hole is about 1
Since the pumping speed can be increased to 2ca or more, which is 00 times higher, the pumping speed is significantly increased, so it can be used even in agricultural water pipes with many undulations, and the phenomenon of air lock and air hammer can be eliminated.

Example Examples of the quick exhaust valve of the present invention are as follows.

Pipe internal pressure 10.0 Kg/crrt
The following is the cross-sectional area of the exhaust hole: 2.0 crA diaphragm area: 115.0C = pilot hole cross-sectional area: 0.04 crA water passage hole cross-sectional area
0.08cm Diameter of float valve 100m Weight of float valve 0.3 to 9 Weight of main valve
0.15 garlic

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view showing a conventional exhaust valve, Fig. 2 is a longitudinal cross-sectional view showing an embodiment of the present invention, Fig. 3 is a cross-sectional view along line AA' in Fig. 2, and Fig. 4 is a longitudinal cross-sectional view showing an embodiment of the present invention. FIG. 5 is a partial vertical sectional view showing a state in which the quick exhaust valve is attached to a water pipe, and FIG. 5 is a sectional view showing another operating state of FIG. 2. In the figure, 1, 4... Valve body, 2, 5... Exhaust hole, 3... Float valve, 6... Chamber 7...
Support, 8...Diaphragm, 9...Main valve, 10...
・Pilot hole, 11... Float guide, 12...
・Water hole, 13... Water pipe, 14... Branch pipe,
15...Rapid exhaust valve, 16.19...-Air, 17.
...Water level in the valve body, 18...Water level in the chamber, 20
···valve seat.

Claims (1)

[Scope of utility model registration request] It has a main valve that opens and closes the exhaust port of the valve body, and a float valve that opens and closes a pilot hole provided in the main valve, and the main valve is supported by a diaphragm at the top of a chamber provided in the main body. 1. A quick exhaust valve, characterized in that the float valve is housed in the chamber and has a water passage hole at the bottom of the chamber.