JP2524632Y2 - Main intake air valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an air valve mainly for intake air.

[Conventional technology]

For example, a dam constructed in a mountainous remote place or the like is provided with facilities as shown in FIG. That is, a main gate 32 is provided at the end of the discharge pipe 31, a sub-gate 33 is provided upstream of the terminal, and switches 34, 35 for operating the respective gates 32, 33 are provided in the upper valve chamber 36. ing. In the valve chamber 36, an air valve connected to a pipe between the main gate 32 and the sub-gate 33 is provided.
37 are provided. The air valve 37 performs an exhaust (air) action when filling a small volume between the sub-gate 33 and the main gate 32 with the main gate 32 closed, and discharges air with the main gate 32 opened. It performs an intake (air) action for preventing cavitation due to negative pressure or the like on the terminal side of the pipe 31.

In a conventionally used air valve, a ring-shaped valve seat plate is mounted on an upper portion of a valve box, and a float type valve body is provided in the valve box corresponding to the valve seat plate. This float type valve body is connected to a lower end of a valve stem, and the valve stem is suspended by a spring. Normally, air flows in and out of the gap between the valve seat plate and the float-type valve body, and when the water pressure in the valve box increases, the float-type valve body rises and the gap is closed. I have. Therefore, if the water storage level does not rise at once and gradually rises at the beginning of flooding, the water leaks for a long time with the gap between the float valve body and the valve seat plate kept open. In some cases, the valve chamber 36 is flooded.

Therefore, as a valve mechanism that has improved this point,
A microfilm of 199979 (Japanese Utility Model Application Laid-Open No. 62-110334) was disclosed. As shown in FIG. 2 in an enlarged manner with reference to FIG. 3, the air valve 37A has a valve box 20 having upper and lower ends opened and arranged in a valve chamber (operation chamber) 36, and has an upper end opening. The lower end opening is connected to the air pipe 24 connected to the discharge pipe 31 located between the main gate 32 and the sub-gate 33, and the lower end opening is connected to the air pipe 24 connected to the outside of the valve chamber. A ring-shaped valve seat plate 21 is arranged at the upper end opening, and an air hole 22a is provided at the upper part and a passage 2 is provided at the lower part.
2b, the float valve body 22 having a hollow structure provided with the valve seat plate.
A cage 28 for accommodating a spherical float 27 for opening and closing the passage 22b is attached to a lower portion of the float valve body 22 and disposed in the valve box 20 in correspondence with 21. The lower end of the valve stem 21b urged by 26 is connected to the upper part of the float valve body 22, and when water from the discharge pipe 31 side enters the valve box 20 and its water level rises, the spherical float 27 is formed. Float and close the passage 22b of the float valve body 22,
When the air passage is shut off and the pressure in the discharge pipe 31 becomes negative,
The spherical float 27 inside 28 descends, and the air outside the valve chamber 36 flows into the discharge pipe 31 side through the air hole 22a and the passage 22b of the float valve body 22, and when the negative pressure is further large, the float valve body 22 Moves away from the valve seat plate 21 against the tension of the spring 25 and descends from the position indicated by the solid line in FIG. 2 to the position indicated by the phantom line, and air flows in between the float valve body 22 and the valve seat plate 21. It is something to do.

[Problems to be solved by the invention]

However, also in the improved air valve shown in FIG. 2, the valve body has a double float valve structure of the float valve body 22 and the spherical float 27, and the spherical float 27 is formed of an appropriate mesh. Because it is stored in basket 28,
The following problems remain. That is, since the valve body has a double float valve structure of the float valve body 22 closely contacting the valve seat plate 21 and the spherical float 27 closing the passage 22b of the float valve body 22, the float valve body 22 has Is easily inclined and displaced with respect to the valve seat plate 21, and the float valve body is attached to the valve seat plate 21.
There is a risk that the 22 cannot be completely sealed. Also,
Since the basket 28 that accommodates the spherical float 27 so as to be vertically movable has a structure in which a large number of holes are formed on the entire surface, water is discharged into the valve box 20 via the discharge pipe 31 and the air pipe 23 at the start of flooding of the dam. When the water level in the valve box 20 rises gradually due to intrusion, the spherical float 27
This causes a time lag between the close closure of the passage 22b of the float valve body 22 and the rise of the water, so that the so-called water upflow cannot be prevented. For this reason, those disposed in a cold region such as a mountain region are frozen, and in a state where the main gate 32 is opened, it is not possible to perform an intake (air) operation on the discharge pipe 31, and a negative pressure Pipes and gates could be damaged by cavitation caused by the

Furthermore, since the float valve element 22 has a hollow structure with a cone-shaped lower part, it is difficult to adjust the balance between the buoyancy and the spring force by the spring 26, and the internal structure becomes large, which causes a problem that the apparatus becomes large. there were.

The present invention solves these problems, and when the water level in the valve box rises at the start of flooding of the dam, the spherical float immediately closes the passage of the main valve body and drains water to the bonnet side. It is another object of the present invention to provide a main intake air valve in which the main valve body does not tilt with respect to the valve seat plate.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a valve box having upper and lower ends opened in a valve chamber, an upper end opening in an air pipe communicating with the outside of the valve chamber, and a lower end opening in a main gate and a sub gate. The air pipe connected to the discharge pipe located between the gate and the air pipe is connected to each other, a vent hole is provided at a lower portion, a through hole communicating with the vent hole is provided at a central shaft portion, and an upper portion is provided at a lower end of a valve stem. The main valve body connected to the valve body is disposed in the valve box by being urged by a spring so as to be tightly closed to a ring-shaped valve seat plate arranged at the upper end opening of the valve box, and provided at a lower portion of the main valve body. A main intake body air valve configured to house a spherical float valve body that opens and closes the vent hole in the guide chamber, wherein the main valve body is formed of a plate-shaped valve body, An indoor rod is suspended from the lower end, and this guide rod is slidably fitted into a guide fixed to the lower part of the valve box, And, a water inlet at the bottom of the guide chamber on the upper side thereof is to provide an intake main form air valve, characterized by comprising an air vent.

[Action]

By means of the above, when the water level in the valve box rises at the start of flooding of the dam, the spherical float valve immediately closes the passage of the main valve and closes the exhaust passage. At this time, the main valve body can be prevented from freezing, and the guide rod prevents the guide chamber and the main valve body from tilting from the lower end of the guide chamber.

〔Example〕

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a front sectional view of the main intake air valve 37B of the present invention. Referring to FIG. 1, the configuration of the main intake air valve 37B will be described. On the cylindrical valve box 1 having a narrow lower portion, openings 4, 3, ( A bonnet 4 having openings 3, 3 in the orthogonal direction (not shown) is attached. A valve stem 5 is provided at the center of the bonnet 4 so as to penetrate through the bonnet 4, a valve element 6 is provided at a lower end of the valve stem 5, and a spring receiver 7 ′ which is fixed to the valve stem 5 by a nut is provided above. And a spring 7 supported on the upper part of the bonnet 4, and the spring 7 urges the valve body 6 to close and close the valve seat plate 2.

The valve element 6 includes a main valve element 6b which opens and closes an intake / exhaust hole 2a having a large opening area formed in the valve seat plate 2, and a small opening area ventilation hole formed below the main valve element 6b. In the example, it has a double structure with a spherical float valve element 6a that opens and closes a vent hole 8a formed in the center of the support plate 8 attached to the lower part of the main valve element 6b. It constitutes a plate-like body without buoyancy. The spherical float valve element 6a is provided in a guide chamber 9 which is integral with the support plate 8. The periphery of the ventilation hole 8a of the support plate 8 of the support plate 8 forms a valve seat 10 of the spherical float valve body 6a. The lower portion of the valve stem 5 has a cylindrical shape having a through hole 11 communicating with the ventilation hole 8 a of the support plate 8, and the lower end thereof is fixed to the support plate 8. The guide chamber 9 is provided with water inlets 9a, 9a at its lower part for raising the spherical float valve body 6a at the time of exhaust.
Are provided, and air holes 9b, 9b, 9b are provided in the upper part. The air at the time of exhaust is supplied to the air holes 9b, 9b,
9b enters through hole 11 and passes through openings 3 and 3 of bonnet 4 via through hole 5a.

As described above, since the main valve body 6b forms a plate-like body, the height of the valve box is smaller than that of a conventional float valve body having a hollow structure (H _S <H in FIGS. 1 and 2). _M ) Yes. Further, unlike the conventional float valve body, it is not necessary to adjust the balance between the buoyancy and the spring force by the spring, and the spring force of the spring 7 can be reduced. Therefore, the distance from the bonnet to the upper end of the valve stem cover body is conventionally reduced. It can be made smaller (K _S > K _M ). Therefore, the internal structure is reduced, and the overall height can be reduced as compared with the conventional structure (L _S > L _M ), so that the size of the device can be reduced.

The spring 7 opens the bonnet 4 at the time of intake,
In order to allow air to flow in from 3, the spring constant is set to release the close contact between the plate-shaped main valve element 6 b and the valve seat plate 2 by opening the plate-shaped main valve element 6 b by the negative pressure in the valve box 1. ing. Reference numeral 14 denotes a connection plate for a duct that communicates with the outside so as to suck and discharge air outside the valve chamber.

On the other hand, a guide rod 12 is suspended from a lower end of the guide chamber 9 and is fixed to a lower portion of the valve box 1 via a rib.
It is configured to slide inside 13 according to the movement of the main valve element 6b.

When the main intake air 37B configured as described above is skirted as the air valve 37 shown in FIG. 3, it operates as follows.

When there is no water in the valve box 1, the spherical float valve body 6a falls to the bottom of the guide chamber 9 while the main valve body 6b is in contact with the valve seat plate 2 by the tension of the spring 7, and the valve is closed. The air hole 8a of the support plate 8 is open away from the seat 10.

From this state, when the small volume between the width gate 33 and the main gate 32 is filled and the air is exhausted, it is required not to discharge the water to the bonnet 4 side, but the spherical float valve body 6a
The valve seat 10 has a small opening area, water flows in from the inlets 9a, 9a at the lower part of the guide chamber 9, and air flows through the through holes 11 from the air holes 9b, 9b, 9b at the upper part of the guide chamber 9. Through the hood 4
Escape to the opening 3,3. At this time, the water flowing from the inlets 9a, 9a is faster than reaching the vent 8a of the support plate 8, and the air pushes up the spherical float valve body 6a to close the vent 8a tightly. It is possible to prevent the water from rising, and water is not simultaneously discharged from the air holes 8a. In addition, since only a small volume of air is allowed to escape, a small opening area is sufficient for the exhaust capacity.

Next, when the main gate 32 is opened and the water is discharged, a negative pressure is generated at the end side of the discharge pipe 31. However, the negative pressure in the valve box 1 immediately opposes the urging force of the spring 7 to cause the main air valve 37B of the main intake air to be discharged. Since the plate-shaped main valve element 6b having a large opening area is opened and air is taken in from the openings 3 and 3 of the bonnet 4, cavitation and the like can be prevented from occurring, and there is no damage to the piping and the gate. .

Further, when the spherical float valve body is closed by the exhaust action, the opening area is small, so that the impact of a water hammer or the like is also small.

On the other hand, the guide rod 12 is attached to the lower part of the guide chamber 9, and the guide rod 12 is slidably fitted to the guide 13 fixed to the lower part of the valve box 1. The body 6b is moved up and down by the valve stem 5 and the guide chamber 12 without tilting in the axial direction, so that the main valve body 6b is not inclined and displaced with respect to the valve seat plate 2, and the valve is moved by the main valve body 6b. The intake and exhaust holes 2a of the seat plate 2 can be completely sealed.

[Effect of the invention]

As described above, according to the main intake air valve of the present invention, the valve body opens and closes the intake and exhaust holes formed in the valve seat plate, and opens and closes the passage formed in the main valve body. A spherical float valve body has a double structure, and the main valve body is formed of a plate-like valve body, and a guide rod is suspended from a lower end portion of a guide chamber accommodating the spherical float valve body. Is slidably fitted into a guide fixed to the lower part of the valve box, so that the main valve body does not tilt and shift with respect to the valve seat plate,
The main valve body can completely seal the intake and exhaust holes of the valve seat plate. Further, since the water inlet is provided at the lower portion of the guide chamber and the air hole is provided at the upper side, the water flowing from the water inlet at the time of exhaust is faster than reaching the ventilation hole of the support plate, so that the air flows into the spherical float valve body. To close the ventilation hole of the support plate, preventing the so-called water squirting, preventing water from being discharged from the ventilation hole of the support plate to the bonnet side, and freezing the main valve body during intake. Can be prevented. Therefore, there is no fear of damaging the pipes and gates due to cavitation due to negative pressure or the like. Further, by using the plate-shaped main valve body, the internal structure can be reduced, and the size of the apparatus can be reduced. Also, the spring does not become large against the buoyancy unlike the conventional structure.

[Brief description of the drawings]

FIG. 1 is a front sectional view of the present invention, FIG. 2 is a front sectional view of a conventional air valve, and FIG. 3 is an explanatory view of a dam suitably used in the present invention. 37B: main intake air valve, 1: valve box, 2: valve seat plate, 4: bonnet, 5: valve stem, 6: valve element, 6a: spherical float valve element, 6b: plate-shaped main valve element, 7 ... spring, 9 ... guide room,
10: Valve seat, 11: Through hole, 12: Guide rod, 13: Guide.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-54-9919 (JP, A) JP-A-56-105175 (JP, A) Fully open 62-110334 (JP, U) Really open 1962 114928 (JP, U) Jiko 37-22379 (JP, Y1) Jiko 58-15716 (JP, Y2)

Claims (1)

(57) [Scope of request for utility model registration] 1. A valve box having upper and lower ends opened is disposed in a valve chamber, an upper end opening is located in an air pipe communicating with the outside of the valve chamber, and a lower end opening is located between a main gate and a sub-gate. Connected to the air pipes connected to the discharge pipe, respectively, and the vent hole at the bottom,
The main valve body, which is provided with a through hole communicating with the ventilation hole in the central shaft portion and whose upper part is connected to the lower end of the valve stem, is tightly closed to a ring-shaped valve seat plate arranged in the upper end opening of the valve box. The main intake air is constituted by accommodating a spherical float valve element which opens and closes the vent hole in a guide chamber provided below the main valve element while being urged by a spring so as to be disposed in the valve box. A valve, wherein the main valve body is formed of a plate-shaped valve body, and an indoor rod is vertically suspended from a lower end of the guide chamber, and the guide rod slides on a guide fixed to a lower portion of the valve box. A main intake air valve, wherein a water inlet is provided at a lower portion of the guide chamber and an air hole is provided at an upper portion of the guide chamber.