JPH0738840U - Exhaust valve - Google Patents

Abstract

(57) [Summary] [Purpose] To suppress the fluctuation of the liquid surface when exhausting under pressure, and to prevent the liquid from being discharged at the same time as air. [Composition] An exhaust valve includes a valve box having an inflow port provided at a lower end thereof, a float housed in the valve box so as to be vertically movable,
A pressure chamber formed in the upper part of the valve box, a sub-valve provided between the inside of the valve box and the pressure chamber, a sub-valve that closes the sub-valve as the float moves upward, and a valve box A main valve opening provided between the inside of the tank and an exhaust opening to the atmosphere, and a main valve that opens the main valve opening as the internal pressure of the pressure chamber rises. A variable throttle valve capable of adjusting the flow rate of exhaust gas from the inside of the valve box is provided between the main valve port and the exhaust port.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an exhaust valve capable of automatically exhausting air or gas in a pipeline such as a sewer pipe to the outside.

[0002]

[Prior art]

 Conventionally, as exhaust valves used in sewer pipes, etc., a valve box with an inflow port at the lower end, a float that is vertically movable inside the valve box, the inside of the valve box and the atmosphere Many are equipped with a valve port provided between the exhaust port communicating with the valve and a valve body that closes the valve port with the upward movement of the float. In this type of exhaust valve, the float is located downward and the valve port is open when water does not flow into the pipe. When liquid flows into the pipe, the water level in the valve box rises and the float also rises, closing the valve port. Therefore, it is possible to prevent the liquid in the pipe from being discharged. Such an exhaust valve is suitable for exhausting a large amount of air in the pipe when the liquid first flows into the pipe (during warm-up), but after the pipe is filled with liquid, However, there is a drawback that the air generated in the pipe cannot be exhausted efficiently. The reason is that when the pipe is filled with liquid, the internal pressure of the valve box constantly acts on the valve body, so the valve body does not open even if the water level in the valve box decreases.

In order to solve such a problem, a pressure chamber is formed in the upper portion of the valve box and the inside of the valve box is formed as disclosed in JP-A-2-138581 and JP-A-2-300755. A sub-valve is installed between the pressure chamber and the valve, which closes the sub-valve when the float moves upward, and opens the main valve when the internal pressure of the pressure chamber rises. Exhaust valves have been proposed. In this case, when air flows into the valve box under normal use (pressure is applied) and the water level in the valve box drops, the compressed air in the valve box flows into the pressure chamber, Internal pressure rises. Therefore, the main valve opens the main valve opening, and a large amount of compressed air in the valve box is exhausted from the main valve opening.

[0004]

[Problems to be solved by the device]

 However, a large-diameter valve is used as the main valve in order to achieve the exhaust capacity required to exhaust a large amount during warm-up. With an exhaust valve having such a large valve, when the valve is opened under pressure, the air inside the valve box is exhausted all at once, so the liquid level inside the valve box swings greatly and There was a risk that the liquid of the above was caught and discharged. This is a serious problem because it means that the wastewater in the sewer pipe is discharged from the exhaust valve to the outside. Therefore, an object of the present invention is to provide an exhaust valve capable of suppressing the fluctuation of the liquid surface when exhausting under pressure and preventing the liquid from being simultaneously exhausted.

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, the exhaust valve of the present invention has a valve box having an inflow port at a lower end thereof, a float accommodated in the valve box so as to be vertically movable, and an upper part of the valve box. A pressure chamber, a sub-valve provided between the inside of the valve box and the pressure chamber, a sub-valve that closes the sub-valve as the float moves upward, and an exhaust that opens to the inside of the valve box and the atmosphere. An exhaust valve having a main valve opening provided between the main valve opening and the exhaust port, and a main valve opening the main valve opening when the internal pressure of the pressure chamber rises. It is equipped with a variable throttle valve that can adjust the exhaust flow rate from the inside of the box.

[0006]

[Action]

 When air flows into the valve box and the water level in the valve box drops under normal use (pressure is applied), the compressed air in the valve box flows into the pressure chamber and the internal pressure of the pressure chamber rises. Therefore, the main valve opening is opened, and a large amount of compressed air in the valve box is exhausted from the main valve opening. At this time, since the variable throttle valve is provided between the main valve port and the exhaust port, the exhaust amount is throttled and the fluctuation of the liquid surface is suppressed. As a result, it is possible to prevent the liquid from being discharged together with the air. During warming up, it is desirable to open the throttle valve to the maximum extent to achieve maximum exhaust capacity, or to install the throttle valve after warming up. Then, when the warming up is completed, the opening of the throttle valve is adjusted to the opening according to the pressure of the pipe. Since the exhaust volume during normal use is much smaller than that during warm-up, reducing the flow rate with the throttle valve has no adverse effect.

[0007]

【Example】

 FIG. 1 shows an example of an exhaust valve according to the present invention, which is specifically attached to the upper portion of sewer pipe via a ball valve (not shown). The exhaust valve is roughly composed of a valve box 1, a housing top 2 and a cover 3, a holder 4 and a float 5.

The valve box 1 is formed in a substantially oval shape, and an inflow port 10 connected to a sewer pipe is formed at a lower end portion thereof. The float 5 is housed inside the valve box 1, and is guided so as to be movable up and down by inserting a shaft center hole 5a of the float 5 into a float guide shaft 11 vertically provided from the holder 4. A baffle 12 facing the inflow port 10 is integrally formed at the lower end portion of the float guide shaft 11, and the baffle 12 prevents the float 5 from being lifted by an air flow or a water flow flowing from the inflow port 10. . A stepped stopper surface 13 is formed on the upper end of the float guide shaft 11, and the upper surface of the float 5 is brought into contact with the stopper surface 13 to regulate the upper limit position of the float 5. A cylindrical receiving metal fitting 25 that slides on the float guide shaft 11 is fixed to the inner surface of the shaft center hole 5a of the float 5.

As shown in FIG. 2, a flange portion 14 is formed on the upper end portion of the holder 4, and the flange portion 14 is fixed to the lower surface of the housing top 2 with a diaphragm 15 interposed therebetween. A pressure chamber 16 is formed below the diaphragm 15, and the pressure chamber 16 and the inside of the valve box 1 communicate with each other through a lateral hole 17 and a sub valve port 18 formed in the holder 4. A valve seat 19 made of a rubber-like elastic material is attached to the lower end of the sub valve opening 18. The outer periphery of the lateral hole 17 is covered with a strainer 20 to prevent foreign matter from entering the sub valve opening 18. A sub-valve 21 for opening and closing the sub-valve port 18 is housed in the axial center of the holder 4 so as to be vertically movable. A pin 21 is formed in a vertical long hole 21a formed at the lower end of the sub-valve 21 from the horizontal direction. 22 is slidably inserted. A spring receiver 23 is inserted through the center of the pin 22, and a spring 24 is interposed between the spring receiver 23 and the sub valve 21. Both ends of the pin 22 are vertically movably inserted into a long hole 25a formed in the upper end of the receiving fitting 25. A cylindrical liquid blocking plate 26 covering the outer periphery of the lateral hole 17 and the pin 22 is fixed to the lower surface of the flange portion 14, and even when the liquid level inside the valve box 1 rises to the vicinity of the lateral hole 17, The blocking plate 26 can prevent the liquid from flowing into the inside thereof.

A valve rod 27 is fixed to the center of the diaphragm 15, and the upper end of the valve rod 27 is fitted into the lower end of the main valve 28. A through hole 27 a that connects the pressure chamber 16 and the exhaust hole 29 is formed in the axial center of the valve rod 27. An orifice 27b that restricts the amount of air leaking from the pressure chamber 16 to the atmosphere is formed in the middle of the through hole 27a, and this orifice 27b has an opening area smaller than that of the auxiliary valve port 18. The upper chamber 30 of the diaphragm 15 communicates with the exhaust hole 29 through a gap between the housing top 2 and the outer peripheral surface of the valve rod 27, and the internal pressure of the upper chamber 30 is maintained at atmospheric pressure.

A valve chamber 31 accommodating the main valve 28 is formed between the housing top 2 and the cover 3, and the valve chamber 31 communicates with the inside of the valve box 1 through a ventilation hole 32. There is. A strainer 34 that prevents foreign matter from adhering to the main valve opening 33 is provided around the valve chamber 31. A valve-closing spring 35 that urges the main valve 28 downward (in the valve-closing direction) is interposed between the cover 3 and the main valve 28. The main valve opening 33 communicates with the outside air through the exhaust hole 29. When the main valve 28 opens the main valve opening 33, the air and gas in the valve box 1 are ventilated 32, the valve chamber 31, the main valve opening. It is exhausted to the atmosphere through 33 and the exhaust hole 29.

A manual operation rod 36 is fixed to the upper surface of the main valve 28, and the operation rod 36 penetrates the cover 3 and projects to the upper surface. When the operating rod 36 is pulled up against the spring 35, the internal pressure of the valve box 1 is rapidly discharged through the main valve opening 33, and the dust and the like adhering to the main valve 28 and the main valve opening 33 can be cleaned. .

One end of an exhaust pipe 40 is connected to the exhaust hole 29, and the other end (exhaust port 40a) of the exhaust pipe 40 hangs downward. A variable throttle valve 41 is attached midway in the exhaust pipe 40 that is hung downward. As shown in FIG. 3, the throttle valve 41 maintains a constant flow rate Q ₁ up to a constant opening θ ₁ by the rotation of the handle 42, and when it exceeds the opening θ ₁ , the flow rate increases in proportion to the opening. It is set to Therefore, no matter how the handle 42 is operated, the throttle valve 41 will not be fully closed, and the pressure on the downstream side of the main valve port 33 (exhaust hole 29, exhaust pipe 40) will be lower than the internal pressure of the valve box 1. Can be kept low. The opening degree of the throttle valve 41 is made variable because the pressure in the pipe in which the exhaust valve is installed varies, and it is necessary to adjust the opening degree according to the pressure. Since the flow rate is throttled by the throttle valve 41 provided in the exhaust pipe 40 in this way, the exhaust flow rate can be freely controlled without changing the valve stroke of the main valve 28, and the inside of the valve box 1 when the main valve 28 is opened. The fluctuation of the liquid surface can be reduced.

Next, the operation of the exhaust valve having the above structure will be described. In the initial state (the state where the liquid does not flow in the pipe), the opening degree of the throttle valve 41 is fully opened. The main valve 28 closes the main valve opening 33 by the repulsive force of the valve closing spring 35. Further, since the liquid does not flow into the valve box 1, the float 5 is at the lower limit position. Therefore, the pin 22 and the sub valve 21 are pulled down by the weight of the float 5 and the sub valve port 18 is opened (see the right half of FIG. 2). Now, when the air or gas inside the sewer pipe flows into the valve box 1 through the inflow port 10, a part thereof flows into the pressure chamber 16 through the lateral hole 17 and the auxiliary valve port 18. The air flowing into the pressure chamber 16 acts as an upward force on the diaphragm 15, that is, as a valve opening force on the main valve 28. At this time, the internal pressure of the valve box 1 and the repulsive force of the valve closing spring 35 act as the valve closing force on the main valve 28, but the pressure receiving area of the diaphragm 15 is much larger than the pressure receiving area of the main valve 28. Immediately, the main valve 28 opens the main valve opening 33. Therefore, the air inside the valve box 1 is exhausted at once through the exhaust hole 29 and the exhaust pipe 40. When the warming up is completed in this way, the handle 42 is turned to adjust the opening degree of the throttle valve 41 to an opening degree according to the pressure of the sewer pipe. When the exhaust ends and the liquid flows into the valve box 1, the float 5 floats to raise the sub valve 21 and close the sub valve port 18 (see the left half of FIG. 2). Therefore, air does not flow into the pressure chamber 16, and the internal pressure of the pressure chamber 16 gradually escapes to the atmosphere via the through hole 27 a of the valve rod 27. As a result, the air pressure acting on the diaphragm 15 decreases, and the main valve 28 eventually closes the main valve opening 33 by the internal pressure of the valve chamber 31 and the valve closing spring 35. When gas flows into the valve box 1 in a normal use state, that is, in a state where the liquid has flowed into the valve box 1, the liquid level drops and the float 5 also starts to drop. Then, the sub valve opening 18 is opened, air flows into the pressure chamber 16, and the diaphragm 15 opens the main valve 28. As a result, the air in the valve box 1 is discharged through the main valve port 33, the exhaust hole 29, and the exhaust pipe 40, but flows through the exhaust pipe 40 because the opening of the throttle valve 41 has been throttled in advance. The displacement is limited and the air is slowly discharged. Therefore, it is possible to prevent the liquid inside the valve box 1 from swaying due to rapid exhaustion, and to prevent the liquid from being discharged together with the air.

In the case of the above embodiment, when the sub valve 21 closes the sub valve port 18, first, while the pin 22 moves through the long hole 25a of the receiving member 25, the float 5 rises alone and the long hole 25a When the lower edge hits the pin 22, the pin 22 is pushed up together. Then, the pin 22 pushes up the sub valve 21 via the spring 24 to close the sub valve port 18. The float 5 rises slightly even after the sub valve 21 closes the sub valve opening 18, but the float 5 eventually hits the stopper surface 13 and stops rising. In this state, the pin 22 is not in contact with the upper edge of the elongated hole 21a of the sub-valve 21 and leaves a slight margin, so that the sub-valve 21 is affected by the internal pressure of the valve box 1 and the spring force of the spring 24. The sub-valve 18 will be closed. That is, no matter how fast the float 5 floats, the sub-valve 21 always closes the sub-valve port 18 with a predetermined force, so that the valve seat 19 is not worn or damaged.

When the sub-valve 21 closes the sub-valve port 18 and the liquid level inside the valve box 1 fluctuates, the float 5 also rocks up and down. The sub-valve 21 also swings in conjunction with the swinging of the float 5, causing so-called chattering in which the sub-valve opening 18 is frequently opened and closed, which may make the operation of the main valve 28 unstable. However, since the long hole 21a is provided between the pin 22 and the sub valve 21, even if the float 5 slightly swings, the sub valve 21 cannot follow because of the long hole 21a. , Chattering is prevented in advance. Further, when the float 5 is lowered, if the liquid level inside the valve box 1 is greatly shaken, or if an airflow or a water flow is introduced from the inlet 10, the float 5 may be largely shaken up and down. Therefore, there is a fear that the sub valve 21 may chatter. However, since the play is provided between the sub valve 21 and the float 5 by the elongated hole 25 a of the receiving fitting 25, chattering due to the swing of the float 5 can be prevented in advance.

The present invention is not limited to the above embodiment. For example, although the float 5 is slidably inserted into the float guide shaft 11, the shaft may be projected upward on the upper surface of the float and a guide surface for slidably guiding the shaft may be provided in the valve box. Good. In this case, a sub valve may be attached to the upper part of the shaft via a spring. Further, in the above embodiment, since the main valve 28 is arranged at the top of the exhaust valve, there is an advantage that the main valve 28 can be easily maintained by simply removing the cover 3. The exhaust valve of the present invention is not limited to the structure as in the embodiment, but is provided with a tandem type valve as disclosed in Japanese Patent Laid-Open No. 2-138581 and a diaphragm as disclosed in Japanese Laid-Open Patent Publication No. 2-35005. It is possible to employ various structures such as those equipped with a floating valve. Further, the throttle valve of the present invention is not limited to the one provided in the exhaust pipe 40 as in the embodiment, but may be provided in the exhaust hole 29. In this case, the exhaust pipe 40 is not always necessary.

[0018]

As is apparent from the above description, according to the present invention, the variable throttle valve capable of adjusting the exhaust flow rate from the inside of the valve box is provided between the main valve port and the exhaust port. When exhausting the air inside the valve box under normal use, that is, under pressure, the exhaust flow rate can be reduced and the fluctuation of the liquid surface can be suppressed. Therefore, it is possible to prevent the liquid from being discharged from the exhaust port at the same time as the air. Also, since the exhaust volume during normal use is much smaller than during warm-up, there is no problem even if the throttle valve reduces the exhaust volume.

[Brief description of drawings]

FIG. 1 is an overall sectional view of an example of an exhaust valve according to the present invention.

FIG. 2 is an enlarged cross-sectional view of a part of FIG.

FIG. 3 is a diagram showing a relationship between an opening degree of a variable throttle valve and a flow rate.

[Explanation of symbols]

 1 Valve Box 5 Float 10 Inlet 16 Pressure Chamber 18 Sub-Valve 21 Sub-Valve 28 Main Valve 33 Main Valve Port 40 Exhaust Pipe 40a Exhaust Port 41 Variable Throttle Valve

Claims (1)

[Scope of utility model registration request] 1. A valve box having an inflow port at a lower end, a float accommodated in the valve box so as to be vertically movable, a pressure chamber formed in an upper part of the valve box, and an inside of the valve box. A sub-valve provided between the pressure chamber, a sub-valve that closes the sub-valve with the upward movement of the float, and a main provided between the inside of the valve box and the exhaust port that opens to the atmosphere. In an exhaust valve equipped with a valve opening and a main valve that opens the main valve opening when the internal pressure of the pressure chamber rises, the exhaust flow rate from the inside of the valve box can be adjusted between the main valve opening and the exhaust opening. Exhaust valve with a variable throttle valve.