JP3778702B2 - Fire hydrant with air valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fire hydrant with an air valve, and more particularly to a fire hydrant with an air valve that can automatically discharge air accumulated in a water pipe.
[0002]
[Prior art]
Conventionally, when air accumulates in the water distribution pipe, the flow path is restricted, the water flow capacity is reduced, and the water discharge is poor. In addition, there is a problem that the portion of the pipe that is constantly in the air pool is accelerated in corrosion, leading to a water leak accident. In addition, a large air reservoir amplifies pressure fluctuations (so-called pulsation) in the pipe, and has a problem that it adversely affects the durability and operation of the connected device.
[0003]
In order to solve such a problem, as shown in FIG. 1, an air valve 4 is provided in the middle of a connection pipe 3 for branching from the water main pipe 1 and connecting to the fire hydrant 2. There has been proposed an apparatus in which the air in 3 is exhausted. Although not shown, the water main 1 is provided with an air valve.
[0004]
However, in the case where the air valve 4 is provided separately from the fire hydrant 2 as described above, a pipe or a joint for connecting the air valve 4 to the connecting pipe 3 is required, and thus there is a problem that the cost of piping equipment is high. . Further, the air accumulated in the connection pipe 3 is relatively less than the air accumulated in the water main pipe 1, and it is not reasonable to provide the air valve 4 individually for exhausting such a small amount of air.
[0005]
[Problems to be solved by the invention]
Therefore, a fire hydrant in which an air valve is integrally provided has been proposed. In the case of this fire hydrant, an air valve storage part is integrally formed in the valve box, and the air valve is stored in this storage part. The inside of the storage portion is connected to the upstream side of the inlet formed in the valve box via a bypass passage.
[0006]
However, when the air valve is integrally provided in the fire hydrant as described above, the valve box becomes large because of the air valve housing portion, the manufacturing cost increases, and a large space is required for arranging the fire hydrant. There is a problem. For this reason, there is a case where this fire hydrant cannot be arranged in an existing space. In addition, air has a property of collecting in the upper part of the pipe. However, since the air valve housing communicates with the upstream side of the inlet of the valve box via the bypass passage as described above, the air accumulated in the inlet is not necessarily There is a problem that the air is not always smoothly guided to the air valve housing portion, and air remains in the inlet.
[0007]
Therefore, an object of the present invention is to provide a small fire hydrant with an air valve that can automatically and reliably exhaust air in a pipe.
[0008]
[Means for Solving the Problems]
To achieve the above object, the present invention provides a valve box, an inlet formed in the valve box and connected to a water pipe, a valve body that opens and closes the inlet, and one end of the valve box is connected to the valve body. a spindle the other end protrudes outside the valve body, formed in the valve box, the fire hydrant with and a flow outlet water flows out flowing from the inlet port with the opening of the valve body, the valve body The valve seat formed on the side of the inlet facing the water pipe side is opened and closed, and the spindle presses the valve body to close the valve seat and lifts the valve body to lift the valve seat. It is intended to operate the valve body to open and the interior of the valve body is formed float chamber which float is accommodated communicates with the float chamber to the lower end of the valve body opposed to the inlet is communication port formed in said valve body, one end communicates with the float chamber, the other Features There communicated to the outside, the air entering the said float chamber is an exhaust passage for exhausting to the outside forming, on one end of the exhaust passage, that the air valve port closed by floating of the float is formed A fire hydrant with an air valve is provided.
[0009]
In the state in which the valve body closes the inflow port, when the air in the water pipe is accumulated in the inflow port, the air is introduced into the float chamber through the communication port. Since the float chamber contains a float, when air accumulates in the float chamber, the water level in the float chamber drops, the float loses buoyancy, moves downward, and opens the air valve port. Therefore, the air is exhausted to the outside through the exhaust passage, and the air pool is eliminated. When the air pool is eliminated, the float rises due to buoyancy, closes the air valve port, and prevents water from being discharged outside through the air valve port.
In addition, water pipes may become negative pressure, such as when water is shut off. In this case, the float descends and opens the air valve port, so outside air is introduced through the exhaust passage and air valve port, and negative pressure is reduced. It can be resolved.
[0010]
In the fire hydrant of the present invention, when the valve body is opened, the high-pressure water in the water pipe is discharged to the outside through the inlet, the inside of the valve box, and the outlet. At this time, the water passing through the inlet flows at a high speed, and the float chamber faces the inlet through the communication port, so the float moves vigorously due to the dynamic pressure of the water and collides with the inner wall of the float chamber. Damage the air valve opening.
Therefore, as described in claim 2, it is desirable that the valve body is provided with a baffle plate that closes the communication port by the dynamic pressure of water that flows when the valve body opens the inflow port. In this case, since the dynamic pressure is shielded by the baffle plate, it does not act on the float, and there is no fear of breakage of the float or damage to the air valve port. The baffle plate need not be completely sealed at the communication port, but may be closed to such an extent that dynamic pressure does not act on the float.
[0011]
According to a third aspect of the present invention, a guide shaft may be fixed to the valve body, and a through hole may be formed in the float so that the guide shaft is inserted and guided in a direction to open and close the air valve port. In this case, even if the dynamic pressure acts on the float in the float chamber, the float is guided in the opening / closing direction by the guide shaft, so that the float can be prevented from colliding with the float chamber wall.
[0012]
It is necessary to discharge a large amount of air in the piping when new piping is installed or when water is passed after water is shut off. Therefore, as in claim 4, an opening having a larger opening area than the air valve port is provided in the ceiling of the float chamber, and is arranged to move up and down in the float chamber and above the float, and rises as the float floats Thus, it is desirable to provide a main valve for closing the opening and to form an air valve port in the main valve. In this case, when the main valve opens the opening, a bypass passage that exhausts the air that has entered the float chamber to the outside without passing through the air valve port is formed, and the main valve closes the opening, An exhaust passage for exhausting the air that has entered the float chamber to the outside through the air valve port is formed. That is, when the main valve opens the opening, the air in the pipe can be rapidly exhausted through the bypass passage.
[0013]
As in claim 5, the exhaust passage and the bypass passage may be communicated with the atmosphere via the inside of the spindle. In other words, one end of the exhaust passage and the bypass passage may be communicated with the valve box of the fire hydrant. However, when dirty water is accumulated in the valve box, the dirty water is discharged when the piping is under negative pressure. There is a risk of inhalation. On the other hand, according to the fifth aspect, since the atmosphere is sucked even when the piping is under negative pressure, there is no possibility that the dirty water in the valve box is sucked.
[0014]
According to a sixth aspect of the present invention, there is provided a threaded portion that is screwed onto the valve body and the spindle, and a guide portion that guides the valve body only in the vertical direction on the valve box, and the spindle is rotatably supported at a fixed position. It is desirable to provide a support portion. In this case, since the valve body can be raised and lowered while rotating the spindle at a fixed position, the overall height of the fire hydrant can be lowered.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
2 to 4 show a first embodiment of a fire hydrant with an air valve according to the present invention, and this embodiment shows an example of an underground fire hydrant.
This fire hydrant includes a valve box (main body) 10 connected to a water main through a connection pipe and a repair valve. A flange portion 11 connected and fixed to the flange portion of the repair valve is integrally formed at the lower end portion of the valve box 10. An inflow port 12 communicating with the water main pipe is formed at the inner center portion of the flange portion 11. Are integrally formed. An annular valve seat 13 is formed at the upper edge of the inlet 12.
[0016]
A gasket 15 mounted on the lower end surface of a valve body 14 that is a lift valve is seated on the valve seat 13 to open and close the inlet 12. A float chamber 16 is formed in the valve body 14, and a float 17 is accommodated in the float chamber 16. A holder 18 serving both as fixing of the gasket 15 and preventing the float 17 from falling is screwed to the lower end of the valve body 14. A plurality of communication ports 18a are formed in a portion of the holder 18 facing the inlet 12 and the inlet 12 and the float chamber 16 are communicated with each other through the communication port 18a. A plurality of communication grooves 17a are formed on the lower surface of the float 17, so that the inlet 12 and the float chamber 16 communicate with each other through the communication grooves 17a even when the float 17 is seated on the holder 18. It is.
[0017]
As shown in FIG. 3, a bearing portion 18b is integrally formed at the center of the holder 18, and a pin 19 is mounted on the bearing portion 18b so as to be movable up and down. The pin 19 is always urged downward by a spring 20 having a weak spring force, and is prevented from coming down by an E-ring 21 attached to the pin 19. A baffle plate 22 that can freely open and close the communication port 18 a is fixed to the lower end of the pin 19. In addition, a screen 23 that prevents underwater scale and the like from entering the float chamber 16 is attached to the communication port 18a.
[0018]
An air valve port 24 is formed at an eccentric position of the ceiling portion of the float chamber 16, and the air valve 25 is configured by the air valve port 24, the float 17, and the float chamber 14. One or a plurality of height adjusting screws 26 are attached to the eccentric position opposite to the air valve port 24. Since the air valve port 24 contacts the eccentric position of the float 17 as described above, a lever amplification action is given to the float 17 and the float 17 can be reduced in weight. When the water level in the float chamber 16 reaches a certain level or more, the float 17 rises, and the upper surface of the float 17 comes into contact with the air valve port 24 and the adjusting screw 26 as shown by the solid line in FIG. 24 is closed. When air accumulates in the float chamber 16, the float 17 tilts with the air valve port 24 as a fulcrum as shown by a broken line in FIG. 3, and the air is discharged from the gap between the float 17 and the air valve port 24. Note that when the water level in the float chamber 16 suddenly drops, the float 17 descends and leaves the air valve port 24 to fully open the air valve port 24.
[0019]
A recess 17 b is formed on the lower surface of the float 17 facing the pin 19. When the baffle plate 22 rises and closes the communication port 18a, the pin 19 also rises. However, since the recess 17b is formed on the lower surface of the float 17, the rise of the pin 19 is not hindered. In the state where the baffle plate 22 closes the communication port 18a and the float 17 floats to the upper end position, a slight clearance is provided between the tip of the pin 19 and the recess 17b.
[0020]
A lower end flange portion 27 a of the spindle 27 is inserted into the upper portion of the valve body 14 and is prevented from coming off by a set screw ring 28. The lower end surface of the spindle 27 is formed as a spherical surface 27 b and is in contact with the center point of the upper end surface of the valve body 14 so as to be slightly swingable. Therefore, a gap 29 a (see FIG. 3) is provided between the lower end flange portion 27 a of the spindle 27 and the set screw ring 28. When the spindle 27 is rotated and advanced downward, the central portion of the valve body 14 is pushed by the spherical surface 27 b and is stably seated on the valve seat 13. At this time, the valve element 14 does not rotate with the spindle 27 due to the frictional force with the valve seat 13, and wear of the gasket 15 is prevented.
The air valve port 24 communicates with the inside of the valve box 10 through an exhaust hole 29b formed in the valve body 14 and the gap 29a. Therefore, an exhaust passage is formed by the air valve port 24, the exhaust hole 29b, and the gap 29a.
[0021]
A male screw 27 c is formed around the lower portion of the spindle 27, and a top 30 that is screwed into the male screw 27 c is held by a lid 31 attached to the upper surface of the valve box 10. A nut 32 for fixing the top 30 is screwed onto the lower surface of the lid 31. A boss portion 31 a that guides the spindle 27 is integrally provided on the upper surface of the lid body 31, and a packing 33 is interposed inside the boss portion 31 a so that the clearance between the spindle 27 and the lid body 31 is removed. Water leakage is prevented. A packing presser 34 for preventing the packing 33 from dropping off is attached to the opening of the boss portion 31a. The upper end of the spindle 27 protrudes to the outside, and a cap 35 that engages with a fire hydrant opening / closing key or the like is attached to the tip of the spindle 27.
[0022]
An outlet 10a that opens upward is formed at the side of the valve box 10, and a connecting pipe 36 is connected to the outlet 10a. A base washer 37, a push ring 38, a base 39, and the like are connected to the upper end of the connecting pipe 36. The base 39 is closed by a base lid 40. A gap is provided between the base lid 40 and the base 39 so that air can communicate therewith. Therefore, the air valve port 24 communicates with the inside of the valve box 10 through the exhaust hole 29b and the gap 29a, and then communicates with the atmosphere through the connection pipe 36 and the base 39.
[0023]
Next, the operation of the fire hydrant having the above configuration will be described.
In the closed state, the gasket 15 of the valve body 14 is in close contact with the valve seat 13 and closes the inlet 12. The water sent from the water main through the connection pipe and the repair valve is closed by the valve body 14, but the air contained in the water accumulates in the vicinity of the inlet 12 which is the uppermost part. At this time, the baffle plate 22 opens the communication port 18 a, and the air accumulated in the inlet 12 is smoothly guided to the float chamber 16 through the communication port 18 a that opens above the inlet 12.
[0024]
When air accumulates in the float chamber 16, the water level in the float chamber 16 falls, and the float 17 loses buoyancy and tilts downward to open the air valve port 24. Therefore, air is exhausted to the outside through the air valve port 24, the exhaust hole 29b, the gap 29a, and the inside of the valve box 10, and the air pool is eliminated. When the air pool is eliminated, the float 17 closes the air valve port 24 again by buoyancy, and prevents water from being discharged to the outside through the air valve port 24.
[0025]
Further, when the water pipe becomes negative pressure such as when water is shut off, the float 17 descends and opens the air valve port 24, so that the outside air passes through the exhaust hole 29 b, the air valve port 24, the float chamber 16, and the inlet 12. To the water pipe. Therefore, the negative pressure can be easily eliminated.
[0026]
Now, when the spindle 27 is turned in the direction of opening with the fire hose connected to the base 39, the inlet 12 is opened by the valve body 14, and high-pressure water is supplied from the main water pipe through the connection pipe and the repair valve. It is sent into the box 10 and water is supplied from the base 39 to the hose. At this time, the baffle plate 22 is pushed upward by the dynamic pressure of the water flowing through the inlet 12, and the communication port 18a is closed (see FIG. 4). Therefore, the dynamic pressure does not directly act on the float 17, and the float 17 does not collide with the inner wall of the float chamber 16 and is damaged, and the air valve port 24 is not damaged.
[0027]
Since the air valve 25 is provided inside the valve body 14 as described above, the valve box 10 does not need to be large, and the fire hydrant can be easily arranged in the existing space. In addition, the casing such as the valve box 10 can be shared with the existing fire hydrant valve box simply by replacing the valve body 14, which can greatly reduce the cost.
[0028]
FIG. 5 shows a second embodiment of the present invention. The same parts as those in FIG.
In this embodiment, a guide shaft 41 is fixed between the valve body 14 and the holder 18, and a through hole 17 c into which the guide shaft 41 can be inserted is formed at the center of the float 17. A clearance is provided between the through hole 17 c and the guide shaft 41 so that the upper end surface of the float 17 can be tilted by a predetermined angle (for example, 5 °) in a state where the float 17 is in contact with the air valve port 24. A lower portion of the guide shaft 41 is inserted into a bearing portion 18 b formed at the center of the holder 18 and is prevented from being detached by a flange 41 a formed on the guide shaft 41. The flange 41a also has a function as a screen presser that prevents the screen 23 disposed above the communication hole 18a from being lifted.
[0029]
In this embodiment, when the inlet 12 is opened by the valve body 14, the dynamic pressure of the water flowing through the inlet 12 also acts on the float 17, but the float 17 is always guided only in the vertical direction by the guide shaft 41. Therefore, there is no possibility that the float 17 collides with the inner wall of the float chamber 16 and is damaged.
[0030]
In the case of the first embodiment (see FIGS. 2 to 4), the baffle plate 22 and the float 17 are formed separately from each other, but they may be integrally connected. In this case, it is necessary to configure the baffle plate 22 to close the communication port 18a at the upper limit position of the float 17 (the position where the air valve port is closed).
Moreover, it is also possible to apply the baffle plate 22 of the first embodiment to the second embodiment. For example, a baffle plate may be inserted through the guide shaft 41 so as to be movable up and down.
[0031]
6 to 8 show a third embodiment of the present invention, and this embodiment also shows an example of an underground fire hydrant. The same parts as those in FIG. 2 and FIG.
In this embodiment, an opening 50 having a larger diameter than the air valve port 24 is formed in the ceiling portion of the float chamber 16 by attaching a ring-shaped packing, and the main valve 51 is formed in the float chamber 16 and above the float 17. Is arranged to be movable up and down. A guide peripheral wall 51a extending downward is formed on the outer peripheral portion of the main valve 51, and the inclination of the main valve 51 is restricted. As the float 17 rises, the main valve 51 rises, and an annular convex portion 51 b is formed on the upper surface of the main valve 51 so that the opening 50 can be closed. The main valve 51 is formed of a lightweight material, preferably a material having a specific gravity slightly larger than 1, so that it can be easily pushed up by the buoyancy of the float 17. A small-diameter air valve port 24 is formed on the lower surface side of the main valve 51, and an exhaust hole 52 is formed from the air valve port 24 to the upper surface of the main valve 51 and to the inner diameter side of the annular convex portion 51b. A cylindrical boss portion 53 projects from the center of the lower surface of the main valve 51, and a bypass hole 54 is formed from the boss portion 53 to the outer peripheral surface of the main valve 51.
[0032]
The float 17 disposed below the main valve 51 is formed in a ring shape, and an inner peripheral surface 17a thereof is guided by the boss portion 53 so as to be movable up and down. The upper surface of the float 17 can freely open and close the air valve port 24 formed on the lower surface of the main valve 51. In this embodiment, a boss portion 53 is provided at the lower portion of the main valve 51, and the ring-shaped float 17 is fitted to the boss portion 53 so as to be movable up and down, but the boss portion 53 is omitted and the main valve 51 is omitted. A disk-shaped float 17 may be arranged on the lower side. In this case, the peripheral wall 51 a of the main valve 51 can guide the outer peripheral surface of the float 17.
[0033]
A cylindrical portion 55 that communicates with the opening 50 protrudes from the center of the upper surface of the valve body 14, and this cylindrical portion 55 is in a first hole (communication hole) 56 formed in the axis of the spindle 27. It is slidably inserted. The first hole 56 communicates with the outside through a second hole (communication hole) 57 formed in the diameter direction. A one-way valve 58 is provided at the upper end of the first hole 56 to allow the air in the float chamber 16 to be exhausted to the outside and prevent external water and the like from being sucked into the float chamber 16. Yes. An exhaust passage is formed by the air valve port 24, the exhaust hole 52, the cylindrical portion 55, the first hole 56 and the second hole 57. A bypass passage is formed by the bypass hole 54, the opening 50, the cylindrical portion 55, the first hole 56, and the second hole 57.
[0034]
The one-way valve 58 prevents the mud from being sucked into the water pipe when the water pipe becomes negative with muddy water or the like around the fire hydrant. . On the other hand, when the valve 58 is not provided, it is possible to remove the negative pressure in the water pipe by rapidly sucking outside air.
[0035]
A flange portion 59 is integrally formed on the outer periphery of the central portion of the spindle 27, and the flange portion 59 is rotatably supported via a washer 61 by a nut 60 screwed to the lower surface side of the lid 31. A guide surface 60a having a substantially square cross section is formed on the inner peripheral surface of the nut 60, and an outer peripheral surface 62a having a substantially square cross section of a guide portion 62 projecting from the upper surface of the valve body 14 is engaged with the guide surface 60a. By doing so, the valve body 14 is guided so as to be movable only in the vertical direction. On the inner peripheral surface of the guide portion 62, a screw portion 62 b that is screwed with a screw portion 63 formed on the outer periphery of the lower end portion of the spindle 27 is formed. Therefore, the spindle 27 is rotatably attached at a fixed position. By rotating the spindle 27, the valve body 14 can be moved up and down and the valve seat 13 can be opened and closed. Since the spindle 27 rotates at a fixed position in this manner, the spindle 27 does not protrude upward from the valve boxes 10 and 31 and the overall height of the fire hydrant can be reduced.
[0036]
In the case of the fire hydrant of the above embodiment, when air is collected in the float chamber 16 in the closed state, the water level in the float chamber 16 is slightly lowered, and the float 17 loses buoyancy and tilts downward. However, since the main valve 51 is in a state in which the opening 50 is closed, the float 17 opens the air valve port 24. Therefore, the air is gradually exhausted to the outside through the exhaust passage, that is, the air valve port 24, the exhaust hole 52, the inside of the cylindrical portion 55, the first hole 56 and the second hole 57 of the spindle 27, and the air pool is eliminated. The When the air pool is eliminated, the float 17 closes the air valve port 24 again by buoyancy, and prevents water from being discharged to the outside through the air valve port 24.
[0037]
When the pipe is newly installed or when water is passed after the water is cut off, the float chamber 16 contains almost no water. Therefore, both the main valve 51 and the float 17 are lowered by gravity, and the main valve 51 opens the opening 50. Therefore, the air that has entered the float chamber 16 does not pass through the air valve port 24, but is bypassed, that is, the bypass hole 54 of the main valve 51, the gap between the main valve 51 and the float chamber 16, the opening 50, and the cylindrical portion 55. And the outside through the first hole 56 and the second hole 57 of the spindle 27. Since the bypass passage has an opening area larger than that of the exhaust passage, the air in the pipe can be exhausted rapidly.
[0038]
In the third embodiment, since the exhaust passage is communicated with the outside air through the inside of the spindle 27, even if water is accumulated in the valve box 10, it is possible to prevent this water from being sucked into the main pipe by mistake. .
Further, in the third embodiment, the bypass hole 54 is formed in the main valve 51, but instead, a predetermined gap is provided between the outer periphery of the main valve 51 and the inner periphery of the float chamber 16, and this The air gap may be used as a bypass passage. However, in the case of the embodiment, since the bypass hole 54 is opened at the center of the lower surface of the main valve 51, the communication port 18a and the bypass hole 54 are provided even when the main valve 51 and the float 17 are lowered to the lower end position. Can be easily communicated with each other, and exhaust can be performed smoothly.
[0039]
In the present invention, the first to third embodiments can be appropriately combined. For example, the float and the main valve as in the third embodiment may be arranged in the float chamber of the valve body of the first embodiment. In this case, an opening communicating with the outside may be provided in the ceiling of the float chamber. Conversely, a float as in the first embodiment may be disposed in the float chamber of the valve body of the third embodiment. In this case, the opening of the main valve and the ceiling of the float chamber can be omitted.
[0040]
In the above embodiment, the fire hydrant in which the spindle and the connection pipe are provided in parallel has been described. However, the present invention can also be applied to a fire hydrant in which the spindle and the connection pipe are connected in series, that is, the spindle is inserted into the connection pipe. In this case, the spindle may be composed of a plurality of members.
Further, the shape of the float is not limited to the substantially disk shape and the ring shape as in the embodiment, and various changes can be made. For example, a spherical float may be used.
[0041]
【The invention's effect】
As is apparent from the above description, according to the present invention, since the air valve is built in the valve body that opens and closes the inlet, the valve box itself does not need to be large, and a small fire hydrant with an air valve can be realized. . In addition, by simply replacing the valve body, a casing such as a valve box can be shared with that of an existing fire hydrant, so that significant cost reduction can be achieved. In addition, since the communication port communicating with the float chamber is formed at the lower end of the valve body facing the inlet, the air accumulated at the inlet can be smoothly introduced into the float chamber via the communication port and exhausted to the outside. it can. Therefore, it is possible to prevent air from remaining at the inlet.
[Brief description of the drawings]
FIG. 1 is a piping diagram of a conventional fire hydrant and an air valve.
FIG. 2 is an overall cross-sectional view of a first embodiment of a fire hydrant with an air valve according to the present invention.
FIG. 3 is a partially enlarged view of FIG. 2;
FIG. 4 is a partially enlarged view when the cap is opened in FIG. 2;
FIG. 5 is an enlarged view of a main part of a second embodiment of the present invention.
FIG. 6 is an overall sectional view of a third embodiment of the present invention.
7 is an enlarged cross-sectional view of a main valve used in the fire hydrant of FIG.
FIG. 8 is a plan view of the main valve shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Valve box 12 Inlet 14 Valve body 16 Float chamber 17 Float 22 Baffle plate 24 Air valve port 25 Air valve 27 Spindle 39 Base 41 Guide shaft

Claims (6)

A valve box, an inlet formed in the valve box and connected to a water pipe, a valve body for opening and closing the inlet, a spindle having one end connected to the valve body and the other end protruding outside the valve box And a fire hydrant that is formed in the valve box, and has an outlet from which water that flows in from the inlet as the valve body opens,
The valve body opens and closes a valve seat formed on the side of the inlet facing the water pipe side,
The spindle presses the valve body to close the valve seat, operates the valve body to lift the valve body and open the valve seat,
A float chamber in which a float is accommodated is formed inside the valve body,
Communication port to the float chamber communicating with the lower end of the inlet opposed to the valve body is formed,
One end of the valve body communicates with the float chamber , the other end communicates with the outside, and an exhaust passage for exhausting the air that has entered the float chamber to the outside is formed.
Said one end of the exhaust passage, with the air valve, characterized in that the air valve port closed by floating of the float is formed hydrant. In the fire hydrant with an air valve according to claim 1,
The aforementioned valve body, with the air valve and further comprising a baffle plate to close the communication port by the dynamic pressure of the water flows when the valve body opens the inlet fire hydrant. In the fire hydrant with an air valve according to claim 1 or 2,
The above valve body guide shaft is fixed to the float is inserted guide shaft, and with an air valve, characterized in that a through hole is guided in the direction to open and close the air valve port is formed hydrant. In the fire hydrant with an air valve according to claim 1 or 2,
The ceiling of the float chamber is provided with an opening having a larger opening area than the air valve port,
Is vertically movable disposed over the float chamber a and the float, the opening closed main valve is provided increases with floating of the float,
The air valve port is formed in the main valve,
The main valve by opening the opening, the bypass passage for exhausting air entering the said float chamber to the outside without passing through the air valve port is formed,
By the main valve closes the opening, with the air valve, characterized by the exhaust passage for exhausting the air entering the said float chamber to the outside via the air valve port is formed hydrant. In the fire hydrant with an air valve according to claim 4,
The exhaust passage and the bypass passage, with air valve, characterized in that it communicates with the atmosphere via a communication hole provided in the interior of the spindle hydrant. In the fire hydrant with an air valve according to any one of claims 1 to 5,
The valve body and the spindle are provided with threaded portions that are screwed together,
The aforementioned valve body, and a guide portion for guiding the valve body only in the vertical direction, the supporting portion and an air valve with hydrants, characterized in that provided for rotatably supporting the spindle in a fixed position.

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