JPH11210909A - Emergency valve for water tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an emergency valve for a water storage tank preventing the water polluted by foreign matters mixed when a broken position is repaired from entering the water storage tank by mistake even if an abnormal situation such as breakage occurs on the upstream side than the installation position of the emergency valve for the water storage tank on a distributing water main pipe. SOLUTION: When a valve main element 14 is closed, the coupling pin 32B of a coupling means 32 is protruded by the excitation of a spring and is automatically coupled with the hook section 31 of a valve casing outer protrusion section 14d in a valve rod section 14D, and the valve main element 14 is held at the fully closed state. After the repair of the broken position of a distributing water main pipe 1 is completed, the water pressure of the distributing water main pipe 1 is recovered to exceed a set value, and the valve main element 14 is prevented from being opened even if this water pressure is introduced into a pressure chamber 16 from a pilot port P5 as a pilot pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water storage tank which is installed in a pipeline between a water distribution main pipe of a water supply facility and an earthquake-resistant water storage tank, and is operated when an abnormal situation such as breakage of the water distribution main pipe occurs. The present invention relates to an emergency valve for a water storage tank that prevents inflow of sewage into a water tank and ensures water flow through a water distribution main pipe.

[0002]

2. Description of the Related Art Conventionally, an inflow which connects an upstream main pipe 1A of a water distribution main pipe 1 and an inlet 2A of an earthquake-resistant water storage tank 2 (hereinafter simply referred to as a water storage tank 2) in a water supply facility as shown in FIG. An inflow valve 4 interposed in the pipe 3, an outflow valve 6 interposed in an outflow pipe 5 for communicating the outlet 2 </ b> B of the water storage tank 2 with the downstream main pipe 1 </ b> B of the water distribution main pipe 1, and an inflow valve 4 in the inflow pipe 3. Upstream position and downstream position of the outflow valve 6 in the outflow pipe 5,
That is, the bypass valve 8 is connected to the bypass pipe 7 that connects the primary side 3A of the inflow pipe 3 and the secondary side 5B of the outflow pipe 5.
An emergency valve for a water tank using a plurality of valves 4, 6, 8 is known. In the drawings, V1, V2, and V3 indicate water control valves.

In the conventional emergency valve for a water storage tank having the above-described structure, the bypass valve 8 and the water control valve V are normally used as shown in FIG.
1 is closed, the inflow valve 4 and the outflow valve 6 and the water control valve V2,
V3 is opened. For this reason, the water is
Main pipe 1A upstream of water distribution main pipe 1 → primary side 3A of inflow pipe 3 →
Inflow valve 4 → flows into water storage tank 2 along the path of secondary side 3B of inflow pipe 3 to be stored. Further, the water that has flowed out of the water storage tank 2 is discharged from the primary side 5A of the outflow pipe 5 → the outflow valve 6 → the secondary side 5B of the outflow pipe 5 →
It flows down the route of the main pipe 1B downstream of the water distribution main pipe 1. In this state, the water storage tank 2 functions as a part of the water pipe.

[0004] For example, when an abnormal situation such as breakage of the water distribution main 1 occurs due to an earthquake or the like and the water pressure of the water distribution main 1 drops below a set value, the water pressure is detected and as shown in FIG. The inflow valve 4 and the outflow valve 6 are closed, and the bypass valve 8 is opened. Therefore, as shown by the arrow, the water flows upstream as shown by the arrow 1A of the main distribution pipe 1 → primary 3A of the inflow pipe 3 → bypass pipe 7 → secondary side 5B of the discharge pipe 5 → downstream of the distribution main pipe 1. It flows down along the path of the main pipe 1B. Thereby, the inflow of sewage into the water storage tank 2 is prevented, drinking water for emergency water supply is secured in the water storage tank 2, and the water supply main pipe 1 is connected to the water distribution main pipe 1 by securing water flow. A usable state such as a fire hydrant (not shown) can be obtained.

[0005] However, the conventional emergency valve for a water storage tank requires three valves of the inflow valve 4, the outflow valve 6, and the bypass valve 8, and the number of used valves increases, and the probability of malfunctioning increases accordingly. For this reason, if at least one of the three valves malfunctions at the time of occurrence of an abnormal situation, even if the inflow of sewage into the water storage tank 2 can be prevented, the inflow of the water distribution main pipe 1 is not ensured, or Even if the water distribution of the water distribution main pipe 1 can be ensured, inconvenience that the inflow of sewage into the water storage tank 2 cannot be prevented occurs. In addition, a large installation space is required.

Therefore, there has been provided an emergency valve for a water tank in which the above-mentioned drawbacks have been solved by reducing the number of valves used and reducing the probability of malfunction of the valve. As shown in FIGS. 7 and 8, this type of emergency valve for a water tank includes one emergency shutoff type butterfly valve 9. Butterfly valve 9
Are the distribution pipe 10A on the water distribution main side and the distribution pipe 1 on the water storage tank side.
0B. The distribution pipe 10A on the water distribution main side is connected to the primary side 3A of the inflow pipe 3 and the secondary side 5B of the outflow pipe 5 through the T-shaped pipe 11, and the distribution pipe 10B on the water storage tank side is connected via the T-shaped pipe 12. To the secondary side 3B of the inflow pipe 3 and the primary side 5A of the outflow pipe 5. In addition, the distribution pipe 10A on the water distribution main pipe side
Is divided into an upper passage 5B1 and a lower passage 3A1, and the water distribution tank side branch pipe 10B is divided into an upper passage 5A1 and a lower passage 3B1. And T-tube 1
1 includes a primary side 3A of the inflow pipe 3 and a branch pipe 1 on the side of the water distribution main pipe.
A partition wall 11A is provided for communicating the lower passage 3A1 at 0A and communicating the secondary side 5B of the outflow pipe 5 with the upper passage 5B1 of the distribution pipe 10A on the water distribution main pipe side. Communicates the secondary side 3B of the inflow pipe 3 with the lower passage 3B1 of the water distribution tank 10B, and the primary side 5A of the outflow pipe 5 and the distribution pipe 1 on the water distribution main side.
Partition 11 for communicating with upper passage 5A1 at 0B
A is provided. In the figure, V1 indicates a water control valve.

With such a configuration, in normal times, the butterfly valve 9 is opened and the water control valve V1 is closed as shown in FIGS. Therefore, as shown by the arrow, the water flows from the upstream main pipe 1A of the water distribution main pipe 1 to the primary side 3 of the inflow pipe 3.
A → T-shaped pipe 11A → Lower passage 3A1 on distribution pipe 10A on water distribution main side → Butterfly valve 9 → Distribution pipe 10B on water storage tank side
Flows into the water storage tank 2 via the lower passage 3B1 → the secondary side 3B of the inflow pipe 3 and is stored therein. Further, the water that has flowed out of the water storage tank 2 is supplied to the primary side 5A of the outflow pipe 5 → the T-shaped pipe 12A → the upper passage 5A1 of the water distribution pipe 10B → the butterfly valve 9 →
The water flows down the passage 5B1 on the upper side of the distribution pipe 10A on the water distribution main pipe side → the T-shaped pipe 11A → the secondary side 5B of the outflow pipe 5 → the downstream main pipe 1B of the water distribution main pipe 1. In this state, the water storage tank 2 functions as a part of the water pipe.

For example, when an abnormal situation such as breakage of the water distribution main pipe 1 occurs due to an earthquake or the like and the water pressure of the water distribution main pipe 1 falls below a set value, this water pressure is detected, and FIG. 9 and FIG. As shown, the butterfly valve 9 closes. For this reason, the water is supplied from the upstream main pipe 1 of the water distribution main pipe 1 as shown by the arrow.
A → Primary side 3A of the inflow pipe 3 → T-shaped pipe 11A → Passage 3A1 on the lower side of the water distribution main pipe 10A → Before the butterfly valve 9 → Passage 5B1 on the upper side of the water distribution main pipe 10A →
The water flows down the route of the T-shaped pipe 11A → the secondary side 5B of the outflow pipe 5 → the downstream main pipe 1B of the water distribution main pipe 1. Thereby, the water tank 2
To prevent the inflow of sewage into the reservoir, secure drinking water for emergency water supply in the water storage tank 2, and connect a fire hydrant (not shown) connected to the water distribution main pipe 1 by securing the water distribution of the water distribution main pipe 1. Can be used.

[0009] However, the above-mentioned emergency valve for a water tank devised to reduce the number of used valves is provided with a distribution pipe 10A on a water distribution main side divided into an upper passage 5B1 and a lower passage 3A1.
And the water dividing tank 10B on the water storage tank side divided into the upper passage 5A1 and the lower passage 3B1, and the lower passage 3A1 of the primary side 3A of the inflow pipe 3 and the distribution main pipe 10A on the water distribution main side. And a T-shaped pipe 11 provided with a partition wall 11A for communicating the secondary side 5B of the outflow pipe 5 and the upper passage 5B1 of the distribution pipe 10A on the water distribution main side, and the secondary side 3B of the inflow pipe 3 and the water storage tank. Lower passage 3B in the side branch pipe 10B
1 and a T-shaped pipe 12 provided with a partition wall 12A for communicating the primary side 5A of the outflow pipe 5 with the upper passage 5A1 of the water splitting pipe 10B on the water storage tank side. In addition, the distribution pipe 10A on the water distribution main pipe side, the distribution pipe 10B on the water storage tank side, the T-shaped pipe 11 and the T-shaped pipe 12 each have a complicated structure, so that it is difficult to manufacture them.

Therefore, the applicant of the present invention has filed Japanese Patent Application No. 9-11 / 1997.
In 372, the number of valves used was reduced, and the probability of the above-mentioned inconvenience occurring in the event of an abnormal situation was reduced, thereby increasing reliability, reducing installation space, and using a complicated structure such as a diversion pipe or T-shaped pipe. An emergency valve for a water tank has been provided which can be easily manufactured by omitting the use of piping materials such as pipes. However, with this water tank emergency valve, when an abnormal situation such as breakage of the water distribution mains due to an earthquake or the like occurs and the water pressure of the water distribution mains falls below the set value, the valve of the valve main body is closed to open the water storage tank. Although it is possible to prevent the inflow of sewage and to secure drinking water in the water storage tank, when the water pressure in the distribution mains is restored after repairing the damaged part of the distribution mains, the valve body opens automatically to store water. The tank will function as part of the water distribution pipeline. Therefore, if an abnormal situation such as breakage occurs upstream of the location of the water tank emergency valve in the water distribution main line, water contaminated by foreign matter mixed in when repairing the damaged part may accidentally enter the water tank. Can be

[0011]

That is, in a water tank emergency valve which has solved the drawbacks of the conventional water tank emergency valve, when the water pressure of the water distribution main pipe is restored after the repair of the damaged part of the water distribution main pipe, the valve is opened. Since the main body opens automatically and the water tank functions as part of the water distribution pipeline, an abnormal situation such as breakage occurs upstream of the location of the water tank emergency valve in the main water distribution line. Then, it is conceivable that water contaminated by foreign matter mixed in at the time of repairing the damaged portion may accidentally enter the water storage tank.

Accordingly, the present invention provides a water tank emergency valve which has solved the drawbacks of the conventional water tank emergency valve. It is an object of the present invention to provide an emergency valve for a water tank in which water contaminated by foreign matter mixed in repairing a damaged portion does not accidentally enter the water tank even if a situation occurs.

[0013]

In order to achieve the above object, an emergency valve for a water storage tank according to the present invention comprises a first inlet connected to a peripheral wall of a cylindrical valve box and connected to an upstream main pipe of a water distribution main pipe. Port and
A first outflow port communicating with the downstream main pipe of the water distribution main pipe, a second outflow port communicating with the inlet of the water storage tank, and a second inflow port communicating with the outlet of the water storage tank are provided, and an axial direction is provided inside the valve box. The valve body is provided with a valve rod portion so as to be freely movable. In normal times, the valve body is moved to one side in the axial direction of the valve box, and the first inflow port and the second outflow port are moved. And, in a valve open state in which the first outflow port and the second inflow port are communicated with each other, the water storage tank functions as a part of a water distribution pipe, and when an abnormal situation occurs, the valve body is moved in the axial direction of the valve box. Moved to the other side, preventing the inflow of sewage into the water storage tank in a valve closed state that communicates the first inflow port and the first outflow port, to secure drinking water in the water storage tank, And an emergency valve for a water storage tank configured to secure water flow through the water distribution main pipe. A locking portion is formed at least at one end in the axial direction of the valve rod portion, and automatically engages with the locking portion so as to be disengageable when the movement of the valve body to the other axial side is completed. And an engagement means for holding the valve body in a closed state.

According to the present invention, when an abnormal situation such as breakage occurs in the water distribution main pipe, the valve body is closed to prevent inflow of sewage into the water storage tank and to secure drinking water in the water storage tank. . This state is maintained by the engagement means automatically engaging with the locking portion of the valve stem. Therefore, even if the water pressure of the water distribution main pipe recovers after the repair of the damaged portion of the water distribution main pipe is completed, the valve opening of the valve main body is prevented. On the other hand, water flow through the water distribution main pipe is ensured while preventing inflow of sewage into the water storage tank. As a result, water contaminated by foreign matter mixed in at the time of repairing the damaged portion can flow down, so that when it is determined that the contaminated water does not accidentally enter the water storage tank, the engagement means and the valve rod portion are removed. By releasing the engagement with the locking portion, the valve body can be opened and the water storage tank can function as a part of the water distribution pipeline.

[0015]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing a partial cross section of one embodiment of the present invention in a normal state. The same or corresponding parts as those of the conventional example are denoted by the same reference numerals and described. In FIG. 1, the emergency valve V for a water tank is
There is provided one cylindrical valve box 13, and a valve body 14 movably mounted in the valve box 13 in the axial direction. The valve body 14 includes a valve stem 14D, a piston 14A attached to one axial end of the valve stem 14D, and a valve stem 14D.
The first valve body portion 1 eccentrically attached to the other end side in the axial direction of D
4B, a piston portion 14F, and a second valve body portion 14C attached to a substantially central portion of the valve stem portion 14D in the axial direction, and includes a piston portion 14A, a first valve body portion 14B, and a second valve body portion 14.
C, the outer peripheral surface of the piston portion 14A and the outer peripheral surface of the piston portion 14F and the inner peripheral surface of the valve box 13 can be water-sealed.

Inside the valve box 13, an annular first valve box sheet 13A, an annular second valve box sheet 13B and an annular third valve box sheet 13C are provided, and a piston portion 14A is provided with an annular first valve. Pressure chamber 16 at one axial end of box sheet 13A
, The piston portion 14F is located in the biasing chamber 17 at the other end in the axial direction, and the first valve body portion 14B is located in the biasing chamber 17.
Located near. The second valve body portion 14C includes an annular first valve box sheet 13A and an annular second valve box sheet 13B.
The outlet chamber 19 is formed between the annular second valve box sheet 13B and the annular third valve box sheet 13C.

On the other hand, the valve box 13 has a first inflow port P1 penetrating the peripheral wall thereof and leading to the inflow chamber 18;
A first outflow port P2 is formed, which penetrates the peripheral wall at a position 180 ° in the circumferential direction from the position where these ports P1 and P2 are formed, and flows into the inflow chamber via the first valve box sheet 13A. Second outflow port P3 leading to 18
And a second inflow port P4 communicating with the outflow chamber 19 via the third valve box sheet 13C. Further, a pilot port P5 is formed through one end of the valve box 13 and communicates with the pressure chamber 16. A biasing means 15 made of a spring is inserted in the biasing chamber 17, and a valve body 14 is provided. Is constantly biased toward one end in the axial direction.

The water tank emergency valve V is provided between the water distribution main pipe 1 and the water tank 2 in the water supply facility. That is, the upstream main pipe 1A of the water distribution main pipe 1 is connected to the first inflow port P1 via the primary side 3A of the inflow pipe 3, and the downstream main pipe 1B of the water distribution main pipe 1 is connected to the secondary side of the outflow pipe 5. 5B, the inlet 2A of the water storage tank 2 is connected to the second outlet port P3 via the secondary side 3B of the inflow pipe 3, and the outlet 2B of the water storage tank 2 is connected to the outlet 2B. The pipe 5 is connected to the second inflow port P4 via the primary side 5A. An upstream main pipe 1A of the water distribution main pipe 1 is connected to a pilot port P5 via a pilot pipe 20. In the figure, V1 indicates a water control valve.

As shown in FIGS. 1 and 2, an opening indicating device 30 for the valve body extending to the other end in the axial direction is provided outside the urging chamber 17. This valve body opening indicating device 3
0 is communicated with the inside of the biasing chamber 17 through a valve rod insertion hole 17a penetrating through the outer end wall portion 17A of the biasing chamber 17 to the outside of the biasing chamber 17 at the other axial end. A cylindrical valve stem cover 30A extending and attached, a valve box outer projection 14d of a valve stem portion 14D inserted into the valve stem cover 30A through the valve stem insertion hole 17a, and a valve stem outside. A fan-shaped or disc-shaped valve opening indicating member 30B fixed to the protruding portion 14d (however, in the present embodiment, the fan-shaped valve opening indicating member 30B is fixed) and a valve opening indicating member 30B. And a viewing window 30C of a valve opening indicating member which extends in the axial direction and extends through the peripheral wall of the valve stem cover 30A. On the peripheral wall portion of the valve stem cover 30A near the viewing window 30C, the other end in the axial direction of the viewing window 30C (one side). ) The biased character is displayed "open", biased in one axial end side of the viewing window portion 30C (the other side) character "closed" is displayed.

On the other hand, a locking portion 31 formed by a step surface is formed on the outside protrusion 14d of the valve rod portion 14D, and the locking portion 31 automatically engages with the locking portion 31 so as to be disengaged. The means 32 penetrates the cylindrical valve stem cover 30A and is mounted orthogonal to the valve box outer projection 14d. The engaging means 32 penetrates through the valve stem cover 30A, and
A, and a cylindrical body 32A having both ends opened and fixed to
A is movably inserted in the axial direction into the cylindrical body A,
An engagement pin 32B protruding from the front end opening of 2A, a spring 32C constantly pressing and biasing this engagement pin 32B toward the front end side, and a plug 32D screwed into the rear end opening of the cylindrical body 32A are provided. An elongated hole 32E is provided on one side of the cylindrical body 32A, and an operation knob 32F attached to the engaging pin 32B is projected outside the cylindrical body 32A through the elongated hole 32E.
Also, in the normal state of FIG. 1, the distal end of the engaging pin 32 </ b> B is in contact with the outer surface of the large-diameter portion on the valve box 13 side with respect to the locking portion 31 formed by the stepped surface of the valve box outer protrusion 14 d. The mounting position of the cylindrical body 32A with respect to the valve stem cover 30A is set.

With such a configuration, in normal times, the water pressure of the water distribution main pipe 1 exceeds the set value, and this water pressure is introduced into the pressure chamber 16 from the pilot port P5 as the pilot pressure. A load is applied to the piston portion 14A, and the valve body 14 is moved to the other axial end of the valve box 13 to open the valve against the urging of the urging means 15. As a result, the first inflow port P1 and the second outflow port P
3 communicate with each other, and the first outflow port P2 and the second inflow port P4 communicate through the outflow chamber 19. For this reason, the water is supplied from the upstream main pipe 1 of the water distribution main pipe 1 as shown by the arrow.
A → primary side 3A of inflow pipe 3 → first inflow port P1 → inflow chamber 18 →→ second outflow port P3 → secondary side 3B of inflow pipe 3
The water flows into the water storage tank 2 through the path shown in FIG. Further, the water that has flowed out of the water storage tank 2 is discharged from the primary side 5A of the outflow pipe 5 → second inflow port P4 → outflow chamber 19 → first outflow port P2 → secondary side 5B of the outflow pipe 5 → downstream of the water distribution main pipe 1. It flows down along the route of the side main pipe 1B. In this state, the water storage tank 2 functions as a part of the water pipe.

In this case, the protruding portion 1 of the valve stem portion 14D outside the valve box is provided.
The valve opening degree indicating member 30B fixed to 4d is located at a full opening instruction position deviated to one side in the axial direction of the cylindrical valve stem cover 30A, that is, at a position corresponding to the display character "open". The fully opened state of the valve main body 14 can be confirmed by visually recognizing the valve opening degree indicating member 30B at the position from the visual window 30C.

For example, when an abnormal situation such as breakage occurs in the water distribution main pipe 1 due to an earthquake or the like, the water pressure in the water distribution main pipe 1 falls below a set value, and the pilot pressure in the pressure chamber 16 becomes low, the urging means 15 is turned on. As shown in FIG. 3, the valve body is brought into contact with the second valve body portion 14C in contact with the first valve box sheet 13A and the first valve body portion 14B in contact with the third valve box sheet 13C as shown in FIG. 14 is moved to one axial end of the valve box 13. Thereby, the first inflow port P1 and the first outflow port P2 communicate with each other via the inflow chamber 18 and the outflow chamber 19. For this reason, as shown by the arrow, the water flows from the upstream main pipe 1A of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the first inflow port P1 →
The water flows down along the route of the inflow chamber 18 → outflow chamber 19 → first outflow port P2 → secondary side 5B of outflow pipe 5 → downstream main pipe 1B of water distribution main pipe 1. Therefore, the inflow of sewage into the water storage tank 2 is prevented, drinking water for emergency water supply is secured in the water storage tank 2, and the fire hydrant connected to the water distribution main pipe 1 by securing the water distribution of the water distribution main pipe 1. A usable state such as (not shown) can be obtained.

In this case, the protruding portion 1 of the valve stem 14D outside the valve box is provided.
The valve opening indicating member 30B fixed to 4d is at a fully closed indicating position biased to the other side in the axial direction of the cylindrical valve stem cover 30A, that is, at a position corresponding to the display character "closed". The fully closed state of the valve body 14 can be confirmed by visually recognizing the valve opening degree indicating member 30B located at the closing instruction position from the visual window 30C.

On the other hand, the engaging pin 32B of the engaging means 32 projects by the bias of the spring 32C and automatically engages with the locking portion 31 of the valve box outside projection 14d of the valve rod portion 14D, and the valve body 14 The fully closed state is maintained. Therefore, even after the repair of the damaged portion of the distribution main pipe 1 is completed, the water pressure of the distribution main pipe 1 recovers and exceeds the set value, and even if this hydraulic pressure is introduced from the pilot port P5 into the pressure chamber 16 as the pilot pressure,
The opening of the valve body 14 is prevented. Therefore, even if an abnormal situation such as breakage occurs upstream of the installation position of the water storage tank emergency valve V in the water distribution main pipe 1, water contaminated by foreign matter mixed in at the time of repairing the damaged portion is erroneously stored. It does not enter the tank 2.

Further, the flow of water through the water distribution main pipe 1 is ensured in a state where the inflow of sewage into the water storage tank 2 is prevented. For this reason, the water contaminated by the foreign matter mixed in at the time of repairing the damaged portion can flow down. Therefore, when it is determined that the contaminated water does not accidentally enter the water storage tank 2, the operation knob of the engaging means 32 is operated. 32F, the engaging pin 32B is retracted against the bias of the spring 32C, and the engaging pin 32B
By releasing the engagement with the valve 1, the valve body 14 can be opened by the pilot pressure, and the water storage tank 2 can function as a part of the water distribution pipeline.

In the above embodiment, the engagement means 32
Is provided on the biasing chamber 17 side, but a configuration in which an engaging means 32 is provided on the pressure chamber 16 side as shown in FIG.

[0028]

As described above, according to the present invention, the state in which the valve is closed when an abnormal situation occurs is maintained by the engagement means automatically engaging with the locking portion of the valve stem. Therefore, even if the water pressure of the water distribution mains recovers after the repair of the damaged part of the water distribution mains is completed, the valve opening of the valve body is prevented. For this reason,
Even if an abnormal situation such as breakage occurs upstream of the installation position of the water tank emergency valve in the water distribution main line, water contaminated by foreign matter mixed in at the time of repairing the damaged part can accidentally enter the water tank. Absent.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a normal state of the present invention.

FIG. 2 is an enlarged sectional view of a main part.

FIG. 3 is a configuration diagram showing one embodiment of the present invention when an abnormal situation occurs.

FIG. 4 is a configuration diagram showing another embodiment of the present invention.

FIG. 5 is a configuration diagram showing a form in a normal state of a conventional example.

FIG. 6 is a configuration diagram illustrating a conventional example when an abnormal situation occurs.

FIG. 7 is a configuration diagram illustrating a form of another conventional example in a normal state.

FIG. 8 is an enlarged sectional view taken along line BB of FIG. 7;

FIG. 9 is a configuration diagram showing another conventional example when an abnormal situation occurs.

FIG. 10 is an enlarged sectional view taken along line CC of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water distribution main pipe 1A Upstream main pipe 1B Downstream main pipe 2 Seismic-resistant water storage tank (water storage tank) 2A Inlet 2B Outlet 13 Cylindrical valve box 14 Valve main body 14D Valve rod part 14d Valve rod outside projection of valve rod part 31 Locking part 32 Engaging means P1 First inflow port P2 First outflow port P3 Second outflow port P4 Second inflow port P5 Pilot port V Emergency valve for water storage tank

Claims (1)

[Claims] 1. A first inflow port communicating with an upstream main pipe of a water distribution main pipe, a first outflow port communicating with a downstream main pipe of a water distribution main pipe, and an inlet of a water storage tank in a peripheral wall portion of a cylindrical valve box. The second leading to
An outflow port and a second inflow port communicating with an outlet of the water storage tank are provided. A valve body having an axially movable valve rod is inserted into the valve box. The main body is moved to one side in the axial direction of the valve box, and the water storage tank is arranged in a valve open state in which the first inflow port and the second outflow port and the first outflow port and the second inflow port are communicated. A valve closed state in which the valve body is moved to the other side in the axial direction of the valve box when an abnormal situation occurs, so that the first inflow port and the first outflow port are communicated with each other. A water tank emergency valve configured to prevent inflow of sewage into the water tank, secure drinking water in the water tank, and secure water flow through the water distribution main pipe, A locking portion is formed at least at one axial end of the valve stem portion. An engagement means for automatically engaging the locking portion so as to be disengageable when the movement of the valve body to the other side in the axial direction is completed and holding the valve body closed is provided. Characteristic emergency valve for water tank.