JPH11257508A - Manual return device for emergency valve for water storage tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent water soiled by foreign matters entrapped into a pipe when a damaged part is repaired from being erroneously entered into a water storage tank even though an abnormal state such as failure happens on a side further upstream from the arrangement position of an emergency valve for the water storage tank in a distributing water main pipe. SOLUTION: Even though the water pressure of a distributing water main pipe 1 is recovered after the repair of the damaged part of the distributing water main pipe 1 is completed, a selector valve 51, a return valve 53 and a sluice valve 55 are closed and an emergency valve V for a water storage tank is retained in a valve closing condition, thereby inflow of soil water into the water storage tank is prevented, and also drinking water is ensured in the water storage tank, and water passing through the distributing water main pipe 1 is ensured. After lapse of a predetermined time after the repair of the damaged part is completed, the return valve 53 is opened by direct or indirect manual operation. Hereby, the sluice valve 55 is opened, the selector valve 51 is opened in association with the opening of the sluice valve 55, and the valve main body of the emergency valve V for the water storage tank can be returned to a normal state that it is opened.

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 a manual return device for 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. And the downstream position of the outflow valve 6 in the outflow pipe 5, that is, the primary side 3A of the inflow pipe 3 and the secondary side 5 of the outflow pipe 5.
A bypass valve 8 interposed in a bypass pipe 7 for communicating with B
An emergency valve for a water tank using three valves 4, 6, 8 is known. In the drawings, V1, V2, and V3 indicate water control valves.

In the emergency valve for a water tank having the above-mentioned construction, the bypass valve 8 and the water control valve V1 are normally closed as shown in FIG. 12, and the inflow valve 4, the outflow valve 6, and the water control valves V2 and V3 are normally closed as shown in FIG. Is opened. For this reason, as shown by the arrow, water flows into the water storage tank 2 through the route of the main pipe 1A on the upstream side of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the inflow valve 4 → the secondary side 3B of the inflow pipe 3. And stored. Further, the water that has flowed out of the water storage tank 2 flows down along the route of the primary side 5A of the outflow pipe 5 → the outflow valve 6 → 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.

[0004] For example, when an abnormal situation such as breakage occurs in the water distribution main 1 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
Opens. 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, this kind of emergency valve for a water tank is
The three valves of the inflow valve 4, the outflow valve 6, and the bypass valve 8 are required, and the number of used valves increases, and the probability of malfunctioning increases accordingly. Therefore, at the time of occurrence of an abnormal situation, if a malfunction occurs in at least one of the three valves,
Even if the inflow of sewage into the water storage tank 2 can be prevented, the inflow of water from the water distribution main pipe 1 cannot be secured, or the inflow of sewage into the water storage tank 2 cannot be prevented even if the water flow through the water distribution main pipe 1 can be secured. Inconvenience 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. 14 and 15, this type of water tank emergency valve includes one emergency shutoff type butterfly valve 9. The butterfly valve 9 is interposed between the distribution pipe 10A on the water distribution main pipe side and the distribution pipe 10B on the water storage tank side. Distribution pipe 10A on the water distribution main side
Is the primary side 3A of the inflow pipe 3 and the outflow pipe 5 through the T-shaped pipe 11.
Is connected to the secondary side 5B, and the diverter 10B on the water tank side is
It is connected to the secondary side 3B of the inflow pipe 3 and the primary side 5A of the outflow pipe 5 through the pipe 12. In addition, the distribution pipe 10 on the water distribution main pipe side.
A is divided into an upper passage 5B1 and a lower passage 3A1, and the water distribution tank side branch pipe 10B is connected to the upper passage 5A1.
And a lower passage 3B1. The T-tube 11 communicates the primary side 3A of the inflow pipe 3 with the lower passage 3A1 of the distribution pipe 10A on the water distribution main pipe side, and connects the secondary side 5B of the outflow pipe 5 to the water distribution main pipe side. A partition wall 11A is provided for communicating with the upper passage 5B1 of the distribution pipe 10A, and the T-tube 12 is provided with the secondary side 3B of the inflow pipe 3 and the lower passage 3B1 of the water distribution tank 10B. The primary pipe 5A is connected to the primary side 5A of the outflow pipe 5 and the distribution pipe 1 on the side of the water distribution main pipe.
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, the butterfly valve 9 is normally opened as shown in FIGS.
The water control valve V1 is closed. 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 T-shaped pipe 11A → the lower passage 3A1 of the distribution pipe 10A on the water distribution main pipe side → Butterfly valve 9 → Diversion pipe 10 on water tank side
B 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, 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 passage 5B1 on the upper side of the distribution pipe 10A on the side of the water distribution main pipe → 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 flows down. 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 occurs in the water distribution main 1 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 the water pressure is detected, as shown in FIGS. 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. 9-14 / 1997.
No. 6496, the number of valves used is reduced, the probability of the above-mentioned inconvenience occurring in the event of an abnormal situation is reduced, thereby increasing reliability and reducing the installation space,
There has already been provided an emergency valve for a water tank that can be easily manufactured by omitting the use of piping materials such as a diversion pipe and a T-shaped pipe having a complicated structure.

As shown in FIGS. 1 and 2, this type of emergency valve for a water tank has one cylindrical valve box 13 and this valve box 1.
3 and a valve body 14 which is movably mounted in the axial direction. The valve body 14 includes a valve stem 14D and a piston 14 attached to one axial end of the valve stem 14D.
A, the first valve body portion 14B and the piston portion 14F which are biased to the other end side in the axial direction of the valve shaft portion 14D, and the second valve which is mounted to a substantially central portion in the axial direction of the valve shaft portion 14D. Body part 14C, a piston part 14A, a first valve body part 14B,
The outer peripheral surface of the second valve body portion 14C, the piston portion 14A, and 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 the 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 through 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 water transmission pipe 20. In the figure, V1 indicates a water control valve.

On the other hand, outside the urging chamber 17, there is provided a valve body opening indicating device 30 extending to the other axial end. The opening degree indicating device 30 of the valve main body communicates with the inside of the biasing chamber 17 through a valve rod insertion hole 17 a penetrating through the outer end wall portion 17 </ b> A of the biasing chamber 17. A cylindrical valve stem cover 30 </ b> A extending outwardly and attached to the other axial end.
A valve stem outside projection 14d of the valve stem 14D inserted through the valve stem insertion hole 17a into the valve stem cover 30A;
A fan-shaped or disk-shaped valve opening indicating member 30B fixed to the valve box outer projection 14d (however, in this embodiment, the fan-shaped valve opening indicating member 30B is fixed) and a valve opening. A valve opening degree indicating member, which corresponds to the outer peripheral portion of the degree indicating member 30B and extends in the axial direction and penetrates the peripheral wall of the valve stem cover 30A. On the peripheral wall of the valve stem cover 30A near the viewing window 30C of the degree indicating member, the character "open" is displayed on the other end side (one side) of the viewing window 30C in the axial direction. Window 30C
The character "closed" is displayed on one side (the other side) in the axial direction.

Further, this type of water tank emergency valve V has an automatic return device 40. The automatic return device 40 is interposed in the water pipe 20 and takes in the water pressure of the water pipe 20 into the diaphragm chamber to open the valve as shown in FIG. 1 in the normal state, and as shown in FIG. 2 when the abnormal situation occurs. A water control valve 41 composed of a diaphragm valve that is closed, a drain pipe 42 branched from the water guide pipe 20 on the downstream side of the water control valve 41, The water pressure on the upstream side of the water control valve 41 is taken into the diaphragm chamber, and the drain valve 43 is constituted by a diaphragm valve which is normally closed as shown in FIG. 1 and which is opened as shown in FIG. And is constituted by.

In the above configuration, the water pressure of the water distribution main pipe 1 and the water conveyance pipe 20 in a normal state exceeds the set value. Since the high water pressure exceeding the set value is taken into the diaphragm chamber of the water control valve 41 from the water pipe 20, the valve is opened, and the high water pressure exceeding the set value from the water pipe 20 is also supplied to the diaphragm chamber of the drain valve 43. The valve is closed as it is taken in. For this reason, the high water pressure exceeding the set value is used as the pilot pressure as the pilot pressure, and the pressure chamber
And load the piston portion 14A of the valve body 14. When a high pilot pressure is applied to the piston portion 14A of the valve body 14, the valve body 14 is moved to the other axial end of the valve box 13 against the urging of the urging means 15, and the emergency for the water storage tank is started. The valve V is opened. Thereby, the first inflow port P1 and the second outflow port P3 communicate with each other via the inflow chamber 18, and the first outflow port P2 and the second inflow port P4 communicate with each other via the outflow chamber 19. For this reason, as shown by the arrow, the water flows in the main pipe 1A on the upstream side of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the first inflow port P1 → the inflow chamber 18 →
→ The second outflow port P3 → flows into the water storage tank 2 on the secondary side 3B of the inflow pipe 3 and is stored. The water that has flowed out of the water storage tank 2 is discharged from the primary side 5A of the outflow pipe 5 to the second inflow port P4.
Outflow chamber 19 → first outflow port P2 → secondary side 5 of outflow pipe 5
B → Flows down the route of the main pipe 1B on the downstream side of the water distribution main pipe 1. In this state, the water storage tank 2 functions as a part of the water pipe.

In this case, the protrusion 1 outside the valve box of the valve stem 14D 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 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, the diaphragm chamber of the water control valve 41 is connected to the water pipe 20 from the water transmission pipe 20. The valve is closed because a low water pressure equal to or less than the set value is taken in, and the valve chamber is opened because a low water pressure equal to or less than the set value is taken from the water guide pipe 20 into the diaphragm chamber of the drain valve 43.
For this reason, the pressure chamber 16 includes a part of the water pipe 20 and the drain pipe 42.
Open to the atmosphere via. As a result, as shown in FIG. 2, the urging of the urging means 15 causes the second valve
The valve body 14 is moved to one axial end of the valve box 13 to a position where it comes into contact with the valve box sheet 13A and the first valve body portion 14B comes into contact with the third valve box sheet 13C. 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 in the main pipe 1A on the upstream side of the water distribution main pipe 1 → the primary side 3A of the inflow pipe 3 → the first inflow port P1 → the inflow chamber 18 → the outflow chamber 19 → the first outflow port P2 → It flows down from the secondary side 5B of the outflow pipe 5 to the downstream main pipe 1B of the 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.

However, in the automatic return device 40 described above,
After the occurrence of an abnormal situation, the damaged part of the water distribution main pipe 1 is repaired, so that the water pressure of the water distribution main pipe 1 is restored to a value exceeding the set value, and at the same time, the water pressure is automatically reset, and the emergency valve V for the water storage tank is reset. FIG.
Will be returned to the normal state shown in FIG. For this reason, muddy water containing earth and sand taken into the main pipe 1 at the time of repair of the water distribution main pipe 1 flows into the water storage tank 2, and the water in the water storage tank 2 cannot be supplied as emergency drinking water. There is a fear.

[0021]

In other words, in the automatic reset device for the water tank emergency valve which has solved the drawbacks of the conventional water tank emergency valve, the water pressure of the water main pipe after the repair of the damaged part of the water main pipe is completed. At the same time as the recovery, the valve automatically opens and the valve body opens, and the water tank functions as a part of the water distribution pipeline. When an abnormal situation such as breakage occurs, water contaminated by foreign matter taken into the water distribution main line when repairing the damaged part may accidentally enter the water storage tank, and the water in the water storage tank may be supplied as drinking water for emergency water supply. There is a possibility that the situation will disappear.

Accordingly, the present invention is directed to a water tank emergency valve which has solved the drawbacks of the conventional water tank emergency valve, and is provided with an abnormality such as breakage at a location upstream of the water tank emergency valve in the distribution main pipe. Provided is a manual recovery device for a water tank emergency valve that can reliably prevent water contaminated by foreign matter from accidentally entering a water tank even when a situation occurs and foreign matter is taken into the pipe when repairing a damaged portion. It is intended for that purpose.

[0023]

In order to achieve the above object, a manual return device for an emergency valve for a water storage tank according to the present invention is provided on a peripheral wall portion of a cylindrical valve box at an upstream main pipe of a water distribution main pipe. The first that leads
An inflow port, 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. A valve body having a valve stem movably in the axial direction is inserted therein, and first biasing means for constantly biasing the valve body toward one side in the axial direction; A pressure chamber for urging the valve body to the other side in the axial direction against the force, and a water guide pipe for communicating the pressure chamber with the water distribution main pipe side, wherein the water pressure on the water distribution main pipe side is set to an operation set value. During normal times that exceed
The valve body is moved to one axial side of the valve box against the urging of the first urging means by the water pressure of the pressure chamber, and the first inflow port, the second outflow port, and the first In a valve-open state in which the outflow port and the second inflow port are communicated with each other, the water storage tank functions as a part of a water distribution pipeline,
When an abnormal situation occurs in which the water pressure on the water distribution main pipe side falls below the operation set value, the valve body is moved in the axial direction of the valve box against the water pressure in the pressure chamber by the urging of the first urging means. 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 a manual return device for a water tank emergency valve configured to secure water flow through the water distribution main pipe, wherein the manual return device includes a switching valve interposed in the water pipe, and at least the switching valve. A bypass passage for bypassing the primary side water conduit on the upstream side to communicate with the secondary water conduit on the downstream side, a return valve provided in the bypass passage, and a secondary valve branched from the secondary water conduit and A pilot pipe for communicating the side water pipe with the pilot pressure chamber of the switching valve; A water control valve interposed in the water conveyance pipe upstream of the branch point between the water pipe and the secondary water conveyance pipe, the valve being normally opened and closed when the abnormal situation occurs, and the water control valve and the branch point A drain pipe branched from the secondary-side water supply between the drain pipe and the drain pipe, and the valve closes when the pressure on the water distribution main pipe side recovers during the normal time and after the occurrence of the abnormal situation, and A drain valve that opens when a situation occurs, wherein the switching valve includes a valve body and a second biasing unit that constantly biases the valve body in a valve closing direction, and a pilot valve of the pilot pressure chamber in the normal state. The valve body is opened by moving the valve body against the bias of the second biasing means by pressure, and the valve body is opposed to the pilot pressure by the biasing of the second biasing means when the abnormal situation occurs. And the valve is closed by moving the switching valve. The water in the pressure chamber of the storage tank emergency valve, the pilot pressure chamber of the switching valve, and the secondary side water pipe is drained, and the return valve is closed after the drain valve is closed due to the pressure recovery on the water distribution main side. After the pilot pressure is generated by opening the manual valve to open the switching valve, the emergency valve for the water storage tank is returned to a normal state by closing the return valve manually.

According to the present invention, when an abnormal situation such as breakage occurs in the water distribution main pipe, the switching valve, the return valve and the water control valve are closed, and the drain valve is opened. For this reason, the water in the pressure chamber of the water storage tank emergency valve, the pilot pressure chamber of the switching valve, and the secondary water pipe is drained through the drain pipe, and the emergency valve for the water storage tank is closed. In addition to preventing inflow, secure drinking water in the water storage tank and secure water flow through the distribution mains. Even if the water pressure in the distribution mains is restored after the repair of the damaged part of the distribution mains is completed, the switching valve, the return valve and the water control valve are closed, so the emergency valve for the water storage tank is closed. Can hold. Therefore, it is possible to prevent the inflow of sewage into the water storage tank, secure drinking water in the water storage tank, and secure water flow through the water distribution main pipe. In addition, drainage from the primary water pipe is prevented by closing the drain valve. Even if foreign matter is taken into the distribution main pipe at the time of repairing the damaged portion, water contaminated by the taken-in foreign substance flows down the distribution main pipe, so that the dirty water does not accidentally enter the water storage tank. .
After a lapse of a predetermined time from completion of repair of the damaged portion, that is, when it is determined that the contaminated water has completely flowed to the downstream main pipe,
By opening the return valve by direct or indirect manual operation, the water control valve is opened, the switching valve is opened with the opening of the water control valve, and the valve body of the water storage tank emergency valve is opened. It can be returned to the opened normal state.

[0025]

An embodiment of the present invention will be described below with reference to the drawings. The structure and operation of the water storage tank emergency valve are the same as those of the water storage tank emergency valve of the comparative example in FIGS. 1 and 2. Therefore, the same or corresponding parts as those of the comparative example are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 3, a manual return device 50 includes a switching valve 51 provided in the water pipe 20, a primary water pipe 20A on the upstream side bypassing the switching valve 51, and a secondary water pipe on the downstream side. A bypass passage 52 that communicates with the air passage 20B, a return valve 53 provided in the bypass passage 52, a pilot pipe 54, a water control valve 55, a drain pipe 56, and a drain valve 57 are provided.

The switching valve 51 is, as shown in FIG.
1A, and a valve body 51B that is movably mounted in the axial direction inside the valve box 51A. The valve body 51B has a valve stem 51C, a piston 51D attached to one axial end of the valve stem 51C, and a valve body 51E attached to the other axial end of the valve stem 51C. And the piston part 5
1D is accommodated in the pilot pressure chamber 51F, and is configured so that water can be sealed between the outer peripheral surface of the piston portion 51D and the inner peripheral surface of the pilot pressure chamber 51F. The valve body 51E is accommodated in the valve chamber 51G. It is constantly urged toward one end in the axial direction by a spring 51H. Also, the valve box 51A
The annular valve box sheet 51I is provided at one end of the valve chamber 51G.
Are provided, and a pilot port 51J communicating with the pressure chamber 51F is provided therethrough.

On the other hand, the valve box 51A has an inflow port 51K and an outflow port 5 which penetrate the peripheral wall and communicate with the valve chamber 51G.
1L is formed, the outlet of the primary water conduit 20A on the upstream side of the water conduit 20 is connected to the inlet port 51K, and the inlet of the secondary water conduit 20B on the downstream side is connected to the outlet port 5K.
1L.

3 and 4, the pilot pipe 54 is branched from the secondary water pipe 20B, and the leading end thereof is connected to the pilot port 51J of the switching valve 51, thereby connecting the secondary water pipe 20B and the switching valve. 51 and a pilot pressure chamber 51F. The water control valve 55 is constituted by a diaphragm valve, and is provided upstream of the branch point of the pilot pipe 54 in the secondary-side water conduit 20B. The water pressure of the secondary-side water conduit 20B is taken into the diaphragm chamber, and the valve is normally opened. The valve closes when an abnormal situation occurs. The drain pipe 56 is branched from a branch point of the pilot pipe 54 in the secondary water conduit 20 </ b> B and between the water control valve 55. The drainage pipe 56 is provided with a drainage valve 57 that takes in the water pressure of the primary side water guide pipe 20A into the diaphragm chamber, closes the valve at normal times, and opens the valve when an abnormal situation occurs. As the return valve 53, a valve having a structure that can be directly opened and closed by manual operation of a handle or a lever, a solenoid valve or an electric valve that can be indirectly opened and closed by remote manual operation of a power supply, or the like is used.

In the above configuration, immediately after the water tank emergency valve V and the manual return device 50 are installed, at normal times when the water pressure of the water distribution main pipe 1 exceeds the set value, first, the return valve 5 in FIG.
3 is preliminarily opened by direct or indirect manual operation. As a result, the water control valve 55 is opened because high water pressure is taken into the diaphragm chamber from the secondary water conduit 20B. The diaphragm chamber of the drain valve 57 is closed because a high water pressure has already been taken in from the primary water pipe 20A. For this reason, a high water pressure is applied to the piston portion 51D in the pilot pressure chamber 51F of the switching valve 51 of FIG. 4 via the secondary water conduit 20B and the pilot pipe 54, and the valve body 51B is subjected to the spring force of the spring 51H. The switching valve 51 is pressed and moved toward the other end in the axial direction to open the switching valve 51 that communicates the inflow port 51K and the outflow port 51L via the valve chamber 51G. Here, the return valve 53 is manually closed.

As described above, the switching valve 51 and the water control valve 55 are opened, and the drain valve 57 is closed, so that the high water pressure exceeding the set value is used as the pilot pressure as the pilot pressure from the water pipe 20 to the pilot port P5. The valve body 14 is introduced into the pressure chamber 16 through the passage.
The water in the water distribution main pipe 1 is stored in the water storage tank 2 and the water storage tank 2 is made to function as a part of the water supply pipe by opening the water storage tank emergency valve V by applying a load to the piston portion 14A. Can be.

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, as shown in FIG. The valve is closed because a low water pressure is taken in from the secondary water pipe 20B, and the diaphragm chamber of the drain valve 57 is opened because a low water pressure is taken from the primary water pipe 20A. Therefore, the pilot pressure chamber 5 in the switching valve 51
1F and the pressure chamber 16 of the water storage tank emergency valve V are opened to the atmosphere via a part of the secondary water conduit 20B and the drain pipe 56.
The valve element 51B of the switching valve 51 is provided with a spring 5 as shown in FIG.
Due to the spring force of 1H, the valve body 51E moves toward one end in the axial direction, and the valve body 51E comes into close contact with the valve box sheet 51I and the inflow port 51E.
The valve is in a closed state in which K and the outflow port 51L are shut off. In addition, since the emergency valve V for the water tank is also closed, the inflow of sewage into the water tank 2 is prevented, the drinking water is secured in the water tank 2, and the water distribution of the water distribution main pipe 1 is secured. Thus, a usable state such as a fire hydrant (not shown) connected to the water distribution main pipe 1 can be obtained.

When the water pressure of the water distribution main pipe 1 is restored by the flow of water after the repair of the damaged part of the water distribution main pipe 1 is completed, the primary side water pipe 20 is inserted into the diaphragm chamber of the drain valve 57 as shown in FIG.
The valve is closed because high water pressure is taken in from A. However, since the switching valve 51, the normally-closed manual valve 53, and the water control valve 55 are closed, the water storage tank emergency valve V can be kept in the valve closed state. For this reason, even if an abnormal situation such as breakage occurs in the upstream main pipe 1A upstream of the installation position of the water storage tank emergency valve V in the water distribution main pipe 1, foreign matter is taken into the pipe at the time of repairing the damaged portion. However, it is possible to reliably prevent water contaminated by the foreign matter from entering the water tank 2 by mistake.
In addition to securing drinking water inside, the water distribution through the water distribution main pipe 1 can be secured to obtain a usable state of the fire hydrant and the like.

After a lapse of a predetermined time from the completion of the repair of the damaged portion, that is, when it is determined that the contaminated water has completely flowed to the downstream main pipe 1B, the return valve 53 is directly or indirectly manually operated as shown in FIG. The valve opens. As a result, the water control valve 55 is opened because high water pressure is taken into the diaphragm chamber from the secondary water conduit 20B. The diaphragm chamber of the drain valve 57 is closed because a high water pressure has already been taken in from the primary water pipe 20A. For this reason, the switching valve 51 opens as shown in FIG. 4 for the above-described reason.

As described above, the switching valve 51 and the water control valve 55 are opened, and the drain valve 57 is closed, so that the water tank emergency valve V
Since the valve is opened, the water in the water distribution main pipe 1 can be stored in the water storage tank 2 and the water storage tank 2 can function as a part of the water pipe. Here, by returning the return valve 53 by manual operation, it is possible to return to the normal state of FIG.

In the above embodiment, the water control valve 55 is interposed in the secondary water conduit 20B. However, as shown in FIG. 9, the water control valve 55 is connected to the bypass passage 5 in the primary water conduit 20A.
A configuration may be provided at a position upstream of the second inlet. As shown in FIG. 10, the water control valve 55 is connected to the inlet of the bypass passage 52 in the primary water pipe 20A and the switching valve 5.
1 may be provided. Further, FIG.
As shown in (5), the water control valve 55 may be provided between the outlet of the bypass passage 52 and the switching valve 51 in the secondary water conduit 20B.

[0037]

As described above, according to the present invention, the switching valve, the normally-closed manual valve, and the water control valve are closed even if the water pressure of the distribution main is restored after the repair of the damaged portion of the distribution main is completed. As a result, the water storage tank emergency valve can be kept in a closed state. For this reason, even 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 is mistakenly injected into the water tank. It does not enter.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a normal state of a comparative example.

FIG. 2 is a configuration diagram illustrating a state when an abnormal situation occurs in a comparative example.

FIG. 3 is a configuration diagram showing one embodiment of the present invention in a normal state.

FIG. 4 is an enlarged sectional view showing a valve open state of a switching valve.

FIG. 5 is a configuration diagram showing an embodiment of the present invention when an abnormal situation occurs.

FIG. 6 is an enlarged cross-sectional view illustrating a switching valve in a closed state.

FIG. 7 is a configuration diagram showing an embodiment of the present invention at the time of pressure recovery.

FIG. 8 is a configuration diagram showing an embodiment at the time of a manual return operation of the present invention.

FIG. 9 is a configuration diagram showing another embodiment of the present invention.

FIG. 10 is a configuration diagram showing another embodiment of the present invention.

FIG. 11 is a configuration diagram showing another embodiment of the present invention.

FIG. 12 is a configuration diagram illustrating a form in a normal state of a conventional example.

FIG. 13 is a configuration diagram illustrating a conventional example when an abnormal situation occurs.

FIG. 14 is a configuration diagram showing a form of another conventional example in a normal state.

FIG. 15 is an enlarged sectional view taken along line AA of FIG. 14;

FIG. 16 is a configuration diagram showing a form when an abnormal situation occurs in another conventional example.

FIG. 17 is an enlarged sectional view taken along line BB of FIG. 16;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 water distribution main pipe 1A upstream main pipe 1B downstream main pipe 2 seismic storage tank (water storage tank) 2A inlet 2B outlet 13 cylindrical valve box 14 valve body 14D valve rod 15 spring (first biasing means) 16 pressure Chamber 20 Water conduit 20A Primary water conduit 20B Secondary water conduit 50 Manual return device 51 Switching valve 51F Pilot pressure chamber of switching valve 51H Spring (second biasing means) 52 Bypass passage 53 Return valve 54 Pilot piping 55 Water control Valve 56 Drain pipe 57 Drain valve 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, and a valve body having a valve rod portion movably in the axial direction is inserted into the valve box. First urging means for urging the valve body to one side thereof, a pressure chamber for urging the valve body to the other axial side against the urging of the first urging means, and the pressure chamber and the water distribution main pipe. A water guide pipe communicating with the water supply side, and in normal times when the water pressure on the water distribution main line side exceeds an operation set value, the valve is opposed to the urging of the first urging means by the water pressure in the pressure chamber. 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. An abnormal condition in which the water pressure on the water distribution main side drops below the operation set value while functioning as a part of the water pipeline. When a situation occurs, the valve body is moved to the other axial side of the valve box against the water pressure of the pressure chamber by the urging of the first urging means, and the first inflow port and the first outflow port are moved. A water reservoir configured to prevent inflow of sewage into the water storage tank, secure drinking water in the water storage tank, and secure water flow through the water distribution main pipe in a valve closed state with the port connected. A manual return device for the tank emergency valve, comprising: a switching valve interposed in the water pipe, an upstream primary water pipe at least bypassing the switching valve, and a secondary water pipe downstream. A bypass passage communicating with the side water conduit, a return valve provided in the bypass passage, and a pilot pipe branched from the secondary water conduit and communicating the secondary water conduit with the pilot pressure chamber of the switching valve. And the water pipe upstream of the branch point between the pilot pipe and the secondary water pipe A water control valve which is interposed at the normal time and which is opened at the normal time and closed at the time of occurrence of the abnormal situation; a drain pipe branched from the secondary water supply between the water control valve and the branch point; A drain valve interposed in a pipe to close the valve at the time of pressure recovery on the water distribution main pipe side during the normal and after the occurrence of the abnormal situation, and to open the valve when the abnormal situation occurs, the switching valve includes: A valve body and second biasing means for constantly biasing the valve body in the valve closing direction, wherein the valve body is normally pressed against the biasing force of the second biasing means by the pilot pressure of the pilot pressure chamber in the normal state. When the abnormal situation occurs, the second urging means moves the valve body against the pilot pressure and closes the valve when the abnormal situation occurs. A pressure chamber of the water storage tank emergency valve and a pilot of the switching valve through the drain pipe Drain the water in the pressure chamber and the secondary water pipe, generate the pilot pressure by manually opening the return valve after closing the drain valve following the pressure recovery on the water distribution main side, and switch the switching valve. A manual reset device for a water tank emergency valve, wherein the water tank emergency valve is returned to a normal state by opening the return valve manually after opening.