JPH11311343A - Emergency cutoff valve system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically and certainly change channels. SOLUTION: An emergency cutoff valve system to change channels is furnished with a main pipe upstream side connecting part 1a, a main pipe downstream side connecting port 1b, a tank inlet side connecting port 2a, a tank outlet side connecting port 2b and an intermediate channel in a value casing (c), the main pipe upstream side connecting port 1a and the tank inlet side connecting port 2a communicate to each other through a first opening and closing valve 4a, the main pipe downstream side connecting port 1b and the tank outlet side connecting port 2b communicate to each other through a second opening and closing valve 4b, the first opening and closing valve 4a and the second opening and closing valve 4b communicate the tank inlet side connecting port 2a and the tank outlet side connecting port 2b to each other at the normal time and communicate the intermediate channel at the time of emergency and block the tank inlet side connecting port 2a and the tank outlet side connecting port 2b. Additionally, it is possible to contract the intermediate channel by interposing a valve element of the opening and closing valve at the time of opening the tank inlet side connecting port 2a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emergency shut-off valve device mainly used for an emergency water storage facility for securing domestic water, fire-extinguishing water, and the like when an emergency such as an earthquake occurs. In the present specification, the term “water” generically represents a fluid.

[0002]

2. Description of the Related Art In the event of an earthquake or the like, a water storage tank adjacent to a main water pipe is installed for the purpose of preventing the outflow and loss of water due to the destruction of the water main pipe and securing water for domestic use and fire extinguishing. By connecting the two water pipes connected to the inlet and outlet of the tank to the main pipe, the tank is normally used as a water flow path to prevent decay due to stagnation of water in the tank, Emergency water storage equipment that sometimes shuts off the tank from the main pipe and retains water in the tank is known.

[0003]

As a conventional device for switching the water distribution path of an emergency water storage system, for example, FIG.
3 is illustrated. This means that two water distribution pipes branched from the main pipe are connected to the inlet and outlet connection ports 2a; 2 of the tank T.
b, and an emergency release valve 73 is provided in the main pipe between these water distribution pipes, and an emergency shutoff valve 71; 72 is provided in the water distribution pipe. The valves 71 and 72 are opened to allow water to flow downstream through the tank T. In the event of an earthquake, the emergency shutoff valves 71 and 72 are closed to secure water in the tank T and the emergency release valve 73 is opened to open the water downstream. It is designed to be able to continue the supply of fire and prepare for fire occurrence.

However, in the above-mentioned emergency water storage system, 1
It is necessary to provide two emergency release valves 73 and two emergency shut-off valves 71; 72, so that the cost is high, the maintenance is difficult, and a large installation space is required.
Since it is necessary to open and close the individual valves simultaneously or in a predetermined order, there is a problem that the operation is complicated.

On the other hand, a four-way butterfly valve 8 as shown in FIG.
1 has also been proposed. This is to rotate the valve body 82 with respect to two orthogonal circular valve seats 83 and 84 to perform the same function of switching the water distribution path as that of the three valves in FIG. is there.

However, in the case of the above-mentioned four-way butterfly valve 81, although the mechanism is compact, in actual production, it is possible to sufficiently seal both the two orthogonal valve seats 83 and 84. In order for the valve body 82 to be seated, high precision is inevitably required in machining and assembly, and there is a problem that the cost is also increased. Also, during the closing operation, the valve
There is strong sliding friction at the seal between the valve seats and the valve seats 83 and 84, and there is also a problem in the durability of the seal member.

[0007] In addition, various four-way valve mechanisms have been proposed, such as four-way switching by moving a plurality of coaxial lift valve bodies to and from a plurality of valve seats. Is based on the technical idea of seating a plurality of valve elements that are fixed to each other on a plurality of valve seats at the same time, so that the sealing performance when closing each valve is simultaneously achieved unless the manufacturing accuracy is significantly increased. The problem remains that it is difficult.

[0008] The present invention provides a simple and rational structure,
We solve these technical problems drastically and design, manufacture,
It is easy to maintain and inexpensive, has automatic and reliable switching of flow paths, has high sealing performance with easy sealing means, and does not cause a problem even if it is large in size. The purpose is to obtain a typical emergency shut-off valve device.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is directed to a method in which a main pipe is provided between a tank provided in parallel with the main pipe and the main pipe upstream of the main pipe. In order to flow the fluid to the downstream side of the main pipe via the tank, in an emergency, the fluid in the tank is shut off from the main pipe, and the fluid on the upstream side of the main pipe flows directly to the downstream side of the main pipe without passing through the tank.
In an emergency shut-off valve device for switching a flow path, a valve box includes a main pipe upstream connection port, a main pipe downstream connection port, a tank inlet side connection port, and a tank outlet side connection port. The port and the main pipe downstream connection port are communicated via an intermediate flow path, the main pipe upstream connection port and the tank inlet side connection port are communicated via a first on-off valve, and the main pipe downstream connection port is connected to the main pipe downstream connection port. The tank outlet side connection port is communicated via a second opening / closing valve, and the first opening / closing valve and the second opening / closing valve are normally operated together in a direction away from the tank to normally open the tank inlet side connection port and the tank outlet side. Each of the connection ports is opened, and in an emergency, both are operated in a direction toward the tank to close each of the tank inlet-side connection port and the tank outlet-side connection port, and the first on-off valve is connected to the tank inlet-side connection port. When the valve is opened, the valve element of the first on-off valve is interposed in the That is configured to narrow the road is a main feature.

In the present invention, the first on-off valve and the second
The on-off valve may be configured to be opened and closed by a drive device. Further, the first opening / closing valve may be driven to be opened / closed by a driving device, and the second opening / closing valve may be constantly urged in the valve closing direction. Further, the driving device includes an urging means for urging the on-off valve in one direction and an operating means for forcibly moving the on-off valve in a direction opposite to the urging direction of the urging means. It may be a configuration. Further, the drive device may be configured to open and close the on-off valve as the fluid pressure of the main pipe increases or decreases from a predetermined pressure value. The drive device may be configured to open and close the on-off valve in accordance with an increase or decrease in the main-line fluid flow rate at a predetermined flow rate value.

Further, the driving device includes a pressure receiving plate housed in a container so as to be able to move forward and backward in a sealed manner, and the main pipe fluid pressure acting before and after the pressure receiving plate and an opposing force between a predetermined pressure means and a predetermined pressure means. The on-off valve may be opened and closed by a balance. Further, a pilot valve device is attached to the driving device, and the pilot valve device is configured to introduce the main pipe fluid pressure into the driving device by a balance between the main pipe fluid pressure and the opposing force of a predetermined pressure means. May be configured to control opening and closing. Further, a pilot valve device is attached to the driving device, and the pilot valve device is provided to the driving device by a balance between a pressure difference between before and after the orifice provided in the main pipe and an opposing force of a predetermined pressure means. The main passage fluid pressure introduction passage may be configured to be opened and closed.

Further, a locking mechanism for holding and releasing the open / close valve at a predetermined open / close position may be provided. Further, the locking mechanism increases or decreases the main pipe fluid pressure at a predetermined pressure value, increases or decreases the main pipe fluid flow at a predetermined flow rate value,
The configuration may be such that the operation of holding and releasing the predetermined position of the on-off valve is performed according to whether or not there is an emergency state detection signal from the detector.

With these configurations, in the emergency shut-off valve device of the present invention, both the first on-off valve and the second on-off valve normally operate in a direction away from the tank to normally connect the tank inlet side connection port and the tank outlet side connection port. Since each of the mouths is open, the water on the upstream side of the main pipe flows to the downstream side of the main pipe via the tank. Therefore, water spoilage due to stagnation in the tank is prevented.

Also, at this time, the valve element of the first on-off valve is interposed in such a state as to block most of the cross-sectional area of the intermediate flow passage between the main pipe upstream connection port and the main pipe downstream connection port. As a result, the flow in the intermediate flow path is restricted and its pressure is reduced, so that both the first and second on-off valves are pushed by the flow in the valve opening direction. The valve opening position is kept stable.

On the other hand, when an emergency occurs, such as when the main pipe is destroyed at the time of the occurrence of an earthquake or the like, the pressure in the main pipe drops abnormally or the flow rate abnormally increases. At this time, the driving device operates in response to the abnormal decrease in the pressure or the abnormal increase in the flow rate, and the first on-off valve and the second on-off valve are both operated in the direction toward the tank, and the tank inlet side connection port and the tank outlet side Close each connection. by this,
The tank and main pipe are shut off to allow the water in the tank to remain and secure domestic water, and the water on the upstream side of the main pipe flows directly to the downstream side of the main pipe without passing through the tank, and Supply can be continued to prepare for a fire or the like.

At this time, the internal pressure of the tank is cut off from the main pipe, which is the pressure source, so that the pressure is reduced. Therefore, both of the first and second on-off valves are There is a tendency for the flow of the main pipe through the intermediate flow path, that is, for both on-off valves, to remain pushed by the flow in the valve closing direction to stably maintain the closed position, and therefore, when both on-off valves are closed. Sealability can be easily achieved by adding a slight biasing force.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings showing embodiments. In the drawings, common portions are denoted by common reference numerals. FIGS. 1 and 2 show a first embodiment of the present invention.
Shows a normal state, and FIG. 2 shows an emergency state. The valve box C of the emergency shutoff valve device includes a main pipe upstream connection port 1a, a main pipe downstream connection port 1b, a tank inlet connection port 2a, and a tank outlet connection port 2b. Main pipe upstream connection port 1a
The main pipe downstream connection port 1b is communicated via an intermediate flow path g, the main pipe upstream connection port 1a and the tank inlet connection port 2a are communicated via a first on-off valve A, and the main pipe downstream connection is established. Mouth 1b
And the tank outlet side connection port 2b are communicated via a second on-off valve B.

In the first on-off valve A, the first valve body 4a pivotally supported by the first valve shaft 5a comes into contact with and separates from the first valve seat 3a provided on the tank inlet side connection port 2a. , The second on-off valve B is a second valve body 4 pivotally supported by a second valve shaft 5b.
b is a second valve seat 3 provided on the tank outlet side connection port 2b
b. In this embodiment, both on-off valves A;
For the valve type of B, the swing type is applied.
The two valve bodies 4a and 4b are both closer to the main pipe than both the valve seats 3a and 3b so that they both open when operated in a direction away from the tank T and close when operated in a direction toward the tank T. It is located in. Various well-known sealing means can be installed between the valve bodies 4a; 4b and the valve seats 3a; 3b.

When the first on-off valve A opens the tank inlet side connection port 2a, the valve body 4a is connected to the intermediate flow path g between the main pipe upstream connection port 1a and the main pipe downstream connection port 1b. The intermediate flow path g is configured to be narrowed by being interposed in such a manner as to block most of the cross-sectional area of the intermediate flow path g. The two valve elements 4a; 4b are provided on the back side, that is, on the receiving part 6 on the opposite side of the valve seats 3a;
a; 6b respectively connected to link arms 7a; 7b,
The other ends of the link arms 7a; 7b are collectively connected to the drive rod 8, and thus to the drive device D.

The driving device D includes an urging member 14 for urging the two valve bodies 4a; 4b in the valve closing direction, and forcing the two valve bodies 4a; 4b in a direction opposite to the urging direction of the urging member 14. Operation means for moving the object. That is, the drive rod 8 is
The connecting members 10; 1 which are always urged by the urging member 14 in the valve closing direction of the two valve bodies 4a; 4b and one end of which has a play-moving part (notch).
1 is connected to the handle shaft 12. The handle shaft 12 is connected to a handle 13 via a screw portion 12t after being prevented from rotating, and is configured to advance and retreat in the axial direction by rotating the handle 13.
2, the connecting member 11 wraps the connecting member 10 within a range inside the notch, and the connecting member 1
The movement range of the drive rod 8 on which the drive rod 8 is mounted is restricted, and the drive rod 8 is forcibly moved by an external operation. By this mechanism, both the valve bodies 4a; 4b can be forcibly opened regardless of the urging force of the urging member 14.

Further, a locking mechanism H for holding and releasing the two valve bodies 4a and 4b at the valve open position is provided. In this locking mechanism H, the locking portion 9 on the drive rod 8 is normally hooked on the locking pin 23, and the locking pin 23 is moved in accordance with the emergency state detection signal from the detector S as shown in FIG. When it is displaced to the right, it is released from the locked state, and the drive rod 8 can move in the valve closing direction. As a driving method of the locking pin 23 of the locking mechanism H, various well-known methods such as a pneumatic / hydraulic type using a cylinder and a piston, an electric type using a motor, and an electromagnetic type using a solenoid can be applied. Further, the detector S may be configured to detect that the pressure in the main pipe falls below a predetermined pressure value or the flow rate in the main pipe exceeds a predetermined flow rate value in response to the occurrence of an emergency condition. It may detect an environmental change in an emergency, for example, vibration due to an earthquake or temperature rise due to a fire, and the transmission method of the detection signal may be any of a variety of well-known methods such as a mechanical type and an electrical signal type. Applicable.

The operation of the emergency shut-off valve device of the present invention will be described with reference to FIGS. 1 and 2 showing the first embodiment. 1 and 2, since the structure inside the valve box C is symmetrical, the main pipe can be used in either the right or left direction in the figure. The description will be made on the assumption that the main pipe flow direction is the left direction in the figure.

In order to set the emergency shut-off valve device to the normal water-flowing state, first, the handle 13 is rotated to pull up the handle shaft 12 in the upward direction in the figure, and eventually, the play motion portion ( The play gap between the connecting members 11 and 10 having the cutout portions is eliminated and the driving rod 8 is pulled up by engagement, and the valve bodies 4a and 4b are forcibly opened while resisting the urging force of the urging member 14. Give a valve. Then, when the two valve bodies 4a; 4b reach the fully open position, the locking pin 23 of the locking mechanism H is advanced leftward in the figure to engage with the locking portion 9 on the drive rod 8, The two valve bodies 4a and 4b are held in an open state while retaining the urging force of the urging member 14 in the valve closing direction. After reaching this state, when the handle 13 is turned in the reverse direction to lower the handle shaft 12 downward in the figure, the connecting member 11;
10 can have a play gap therebetween, that is, a state in which the valve closing movements of the two valve elements 4a; 4b in an emergency are not hindered. As a result, in the normal state shown in FIG. 1, since the two valve bodies 4a and 4b open the valve seats 3a and 3b, respectively, the water on the upstream side of the main pipe is 1a → 2a → T → 2
On the route of b → 1b, it flows downstream of the main pipe via the tank T. Therefore, decay of water due to stagnation in the tank T is prevented.

At this time, the first valve body 4a is interposed in such a state as to block most of the cross-sectional area of the intermediate flow path g between the main pipe upstream connection port 1a and the main pipe downstream connection port 1b. Therefore, the flow from the main pipe upstream connection port 1a toward the inside of the intermediate flow passage g is restricted, and the pressure on the back side of the two valve bodies 4a; 4b, that is, the pressure on the intermediate flow passage g side is reduced. Both valve bodies 4a; 4b
Are kept pushed by the flow in the valve opening direction, and the valve opening position is stably maintained. At the same time, the small flow flowing in the path of 1a → g → 1b while being squeezed by the first valve body 4a also prevents stagnation in the intermediate flow path g.

On the other hand, when an emergency occurs, such as when the main pipe is destroyed at the time of occurrence of an earthquake or the like, the pressure in the main pipe drops abnormally or the flow rate abnormally increases. At this time, the detector S of the present apparatus detects an abnormal decrease in the pressure, an abnormal increase in the flow rate, and the like, and accordingly, the locking mechanism H is released, and the urging force of the urging member 14 moves both the drive rod 8. The valve bodies 4a and 4b are driven in the valve closing direction, that is, downward in the figure, and the first valve body 4a is connected to the first valve seat 3 as shown in FIG.
a, the second valve body 4b is seated on the second valve seat 3b, respectively, and closes the tank inlet side connection port 2a and the tank outlet side connection port 2b. As a result, the tank T and the main pipe are shut off, the water in the tank T remains, and water for daily living can be secured. In addition, the water on the upstream side of the main pipe does not pass through the tank T and 1a →
By flowing directly to the downstream side of the main pipe along the path of g → 1b, the supply of water to the downstream side can be continued to prepare for a fire or the like.

At this time, since the internal pressure of the tank T is cut off from the main pipe, which is the pressure source, the pressure is reduced, so that the two valve bodies 4a and 4b pass through the intermediate flow path g. 4b, that is, the two valve bodies 4a and 4b tend to be pushed by the flow in the valve closing direction to stably maintain the closed position, and therefore, when the two valve bodies 4a and 4b are closed. Sealability can be easily achieved. The fact that the two valve bodies 4a and 4b tend to stably maintain the closed position by the flow of the main pipe as described above means that the two valve bodies 4a and 4b tend to stably maintain the closed position.
a means that the force of the urging member 14 for urging the 4b in the valve closing direction may be small. For example, if the position of the tank T is not as high as the left side of the main pipe, it may be small enough to prevent natural overflow due to the weight of the residual water in the tank T in the event that the pressure of the main pipe is lost. However, in the case of a specification condition in which only the urging force due to the weight of the two valve bodies 4a; 4b is sufficient, the urging member 14 may even be omitted. Conversely, when the pressure of the residual water is high, such as when the tank T is located at a position higher than the main pipe,
It goes without saying that appropriate adjustments may be made according to the situation at the facility site, such as increasing the force of the urging member 14 accordingly.

After the repair on the downstream side of the main pipe has been completed, in order to return to the normal water flow state, the aforementioned valve opening operation may be performed again. That is, the handle 13 is rotated to operate the two valve bodies 4.
4a may be forcibly opened while resisting the urging force of the urging member 14, and may be engaged with the locking mechanism H at the valve-opening position to maintain the valve open state.

As described above, according to the present invention, the switching of the flow path can be performed automatically and reliably with a simple structure, and the degree of blockage of the intermediate flow path g when the first valve body 4a is opened is determined as follows. Leakage is tolerated, and it does not have to be hermetically sealed (of course, there is no problem if it is formed so as to be hermetically sealed), so the requirements for production accuracy are not strict, and design, production, maintenance and management are easy and costs are low. It is cheap. Also, in the present invention, both valve elements 4
a; When 4b is in either the valve-opening position or the valve-closing position,
Since it has a tendency to automatically maintain the position by using the flow force (dynamic pressure) at that time, it is necessary to close the valve and maintain the sealing with the valve seats 3a and 3b. The biasing means may be compact, and furthermore, the two valve bodies 4a;
Has a small pressure difference (static pressure difference) before and after, and a small force is required for driving the two valve bodies 4a; 4b.
The requirements for the strength of each operating member are not strict, and the driving device D has a remarkable feature that it can be formed compact.

The operating means for forcibly moving the two valve bodies 4a and 4b is not limited to the one illustrated in this drawing, and the screw portion 12t of the handle shaft 12 is simply attached to the screw portion on the valve box C side. Various well-known conventional techniques, such as screwing, rotating and moving up and down while moving up and down, and mounting and automation of an actuator instead of manually operating the handle 13 can be applied. In addition, it goes without saying that various well-known methods can be applied to the connection members 10 and 11 having the play motion parts, in addition to the connection method using the notch as illustrated in FIG.

FIG. 3 shows a second embodiment of the present invention and shows a normal state. In this embodiment, the second valve element 4b in the first embodiment is separated from the drive by the driving device D and made independent, and is always urged by the urging member 16 in the valve closing direction. In this case, the second
Normally, the valve body 4b is 1a → 2a → T →
The urging member 16 is pushed by the flow flowing in the path of 2b → 1b.
Keeps the valve open against the urging force of
It is switched by the first valve body 4a and is pushed by the flow flowing in the path of 1a → g → 1b, and the urging force of the urging member 16 is also added, so that the closed state can be stably maintained, and therefore, the closed state can be maintained. The same operation and effect as in the first embodiment can be obtained except that the flow direction of the main pipe is limited to the flow in the left direction in the figure. In addition, by distributing the mounting link position of the urging member 16, the urging force to the second valve body 4 b is reduced.
When the valve is opened, the loss resistance is reduced to a minimum value, and when the valve is closed, the loss resistance is maximized to further improve the sealing performance. Other configurations and operation modes are the same as those of the first embodiment, and thus detailed description is omitted.

FIG. 4 shows a third embodiment of the present invention, and shows a normal state. In this embodiment, the valve shafts 5a and 5b of the valve bodies 4a and 4b in the first embodiment are extended outside the valve box C while sealing them, and connected to the driving device D outside the valve box C. is there. Even in this case, the valve shafts 5a;
Since the members around b do not receive an abnormal torsional moment due to the static pressure difference between the valve elements 4a and 4b, the structure around the valve shafts 5a and 5b is compact. In addition,
By separately urging the valve bodies 4a; 4b in the valve closing direction, for example, by attaching a counterweight 17 to the valve shafts 5a; 5b, the valve bodies 4a;
This figure also shows that the seating sealing property of b can be further improved. This counter weight 1
Needless to say, a spring or the like may be applied in place of 7.
Regarding the valve closing urging force of the valve bodies 4a and 4b, the urging member 14 and the counterweight 17 may be used together as shown in this drawing, or only one of them may be used depending on the specification conditions. Other configurations and operation modes are the same as those of the first embodiment, and thus detailed description is omitted.

FIG. 5 shows a fourth embodiment of the present invention, and shows a normal state. In this embodiment, as an example of the locking mechanism H in the first embodiment, a cylinder / piston structure that drives the locking pin 23 to advance and retreat as the pressure in the main pipe increases and decreases at a predetermined pressure value is applied. It was done. That is, a pressure receiving plate 22 is hermetically housed in the cylinder portion 21 via a seal member so as to be able to advance and retreat.
The locking pin 23 is driven forward and backward by the balance between the main pipe pressure acting before and after the pressure receiving plate 22 and the opposing force of the predetermined pressure means. A pressure chamber i is formed on one side of the pressure receiving plate 22 (a side on which the locking pin 23 is pressed toward the locking portion 9), and a pressure chamber i is formed between the cylinder 21 and the other side. It is urged by an urging member 24 as a predetermined pressure means. The urging member 24 can adjust the operating pressure by the urging force adjusting unit 25. The pressure chamber i has an open / close valve 31 which is normally open.
While communicating with the main pipe through a communication passage 31t provided with
Normally, it is communicated with the atmosphere via an on-off valve 32 which is closed.

In the normal operation shown in FIG. 5, the main pipe pressure water reaches the pressure chamber i via the on-off valve 31 and the communication passage 31t, and the internal pressure of the pressure chamber i applied to the pressure receiving plate 22 is reduced. Overcoming the force of the urging member 24, the locking pin 23 is pushed to the left in the drawing. Therefore, the two on-off valves A and B are locked and held by the locking mechanism H in the open state. On the other hand, when an emergency occurs and the internal pressure of the pressure chamber i (that is, the main pipe internal pressure) drops abnormally, the force of the urging member 24 exceeds the internal pressure of the pressure chamber i, and the locking pin 23 is moved to the position shown in FIG. When driven in the right direction, the locking mechanism H is released, the on-off valves A and B are closed, and the tank T is shut off from the main pipe.

Next, when the main pipe is drained for repair work, the internal pressure of the pressure chamber i further decreases, and the locking pin 23 is still being pushed to the right in the figure. . In order to return to the normal flow path via the tank T after the main pipe repair is completed, the two open / close valves A and B are forcibly pulled up by rotating the handle 13, but at that time, the open / close valves that have been opened up to that time are used. 31 is closed, and the on-off valve 32 which has been closed is opened to open the pressure chamber i to the atmosphere, and the urging member 2 is opened.
4 keeps the locking pin 23 shifted rightward in the figure. Then, both the on-off valves A and B are pulled up to the fully opened state, and after the locking portion 9 has passed through the locking pin 23, the on-off valve 32 is closed again, the on-off valve 31 is opened, and the pressure in the main pipe is applied to the pressure chamber i. Then, the locking pin 23 is moved to the left in the drawing to engage with the locking portion 9. With this operation, the emergency cutoff valve device returns to the normal state. In addition, when a situation (for example, inspection) that wants to be shut down urgently occurs despite the normal water flow, the on-off valve 31 is closed,
Open the on-off valve 32, release the locking mechanism H and open both on-off valves A;
B can be forcibly closed. Other configurations and operation modes are the same as those of the first embodiment, and thus detailed description is omitted.

FIG. 6 shows a fifth embodiment of the present invention, and shows a normal state. In this embodiment, the driving device D in the first embodiment is provided with a pressure receiving plate hermetically and movably accommodated in a container, and the main pipe pressure acting before and after the pressure receiving plate and a predetermined pressure means are provided. The two on-off valves A and B are driven to open and close by the balance of the opposing acting forces. That is, the cylinder 41 of the container adjacent to the valve box C is provided with a pressure receiving plate 42 housed in a sealingly and movably movable manner via a sealing member, and the pressure rod 42 drives the drive rod 8 to move forward and backward. A pressure chamber j is formed between one side of the pressure receiving plate 42 (the side that pushes the drive rod 8 toward the valve opening direction) and the cylinder 41, and the other side is communicated with the atmosphere and has a predetermined pressure. It is urged by an urging member 44 as a means. The urging member 44 can adjust the operating pressure by the urging force adjusting unit 45.
The pressure chamber j is communicated with the main pipe through a communication passage 33t having an open / close valve 33 which is normally open, and is communicated with the atmosphere via an open / close valve 34 which is normally closed. The pressure receiving area of the pressure receiving plate 42 is desirably larger than the total pressure receiving area of the valve bodies of the two on-off valves A and B for reliable operation.

Looking at the operation, in the normal state shown in FIG. 6, the main pipe pressure water reaches the pressure chamber j via the on-off valve 33 and the communication passage 33t, and the internal pressure of the pressure chamber j applied to the pressure receiving plate 42 is reduced. By overcoming the force of the urging member 44, the drive rod 8 is driven in the upward direction in the figure, and the two on-off valves A and B are pulled up to the fully opened state. On the other hand, when an emergency occurs and the internal pressure of the pressure chamber j (that is, the main pipe internal pressure) drops abnormally, the force of the urging member 44 exceeds the internal pressure of the pressure chamber j, and the drive rod 8 is moved downward as shown in the figure. And the two valves A and B are closed and the tank T is shut off from the main pipe. Next, when the main pipe is drained for repair work, the internal pressure of the pressure chamber j further decreases, the drive rod 8 is pushed downward in the figure, and the tank T is kept shut off from the main pipe. is there.

If it is desired that the two on-off valves A and B automatically return to the normal open state when water is supplied again after the main pipe repair is completed, the on-off valve 33 is kept open.
The on-off valve 34 may be kept closed, and the internal pressure of the pressure chamber j increases due to the return of the internal pressure of the main pipe due to the resumption of water flow,
Both on-off valves A and B are automatically opened. However, in actual use, there is a case where it is desired to maintain the tank T in an emergency state in which the tank T is disconnected from the main pipe even after the main pipe repair is completed until the safety of the surroundings is confirmed (for example, the tank T is in a closed state). To prevent the mains from being contaminated by dirty mains water immediately after resumption of water supply). The configuration shown in the figure can also respond to such a request. That is, during the repair work of the main pipe, the on-off valve 33 which has been open is closed, the on-off valve 34 which has been closed is opened, the pressure chamber j is opened to the atmosphere, and the urging force of the urging member 44 is used. Both valves A and B are closed and the tank T is kept shut off from the main pipe.
Next, even when the repair is completed and the water supply is resumed, if the on-off valves 33 and 34 are left as they are, the tank T remains shut off from the main pipe. Then, when it is determined that the normal state can be restored, the on-off valve 34 is closed again, the on-off valve 33 is opened, the main pipe pressure is introduced into the pressure chamber j, and both on-off valves A and B are fully opened. To raise. Only when this operation is performed, the emergency shut-off valve device returns to the normal state, which is extremely effective for protection of cleanliness in the tank T and the like.

On the other hand, when there is a situation (for example, an inspection) that the emergency shutoff should be performed in spite of normal water flow,
The on-off valve 33 is closed, the on-off valve 34 is opened, and the pressure chamber j
Can be opened to the atmosphere, and both on-off valves A and B can be forcibly closed. It should be noted that the communication passage 35t with the on-off valve 35 in the figure is provided with the tank T when the on-off valves A and B become difficult to open due to a large differential pressure between the tank T side and the main pipe side.
And a bypass passage provided to facilitate opening of both on-off valves A and B by communicating with the main pipe flow path. The on-off valve 35 is normally closed. The communication passage 3 with the on-off valve 35
5t may be omitted if the specification is not required. Other configurations and operation modes are the same as those of the first embodiment, and thus detailed description is omitted.

FIG. 7 shows a sixth embodiment of the present invention, and shows a normal state. In this embodiment, in the driving device D of the fifth embodiment, the pressure chamber j is integrated into the valve box C so as to be always in communication with the main pipe flow path, and the two on-off valves A; As a mechanism for maintaining the closed state, a locking mechanism H is employed instead of operating the open / close valves 33; That is, when both the on-off valves A and B are closed, the locking pin 23 of the locking mechanism H and the locking portion 9 are engaged to mechanically hold the on-off valves A and B in the closed state. After the repair of the main pipe is completed and the flow of water is resumed, if the locking pin 23 is pulled rightward in the drawing to release the engagement, the two open / close valves A and B are automatically operated by the action of the pressure chamber j. Open the valve. It is needless to say that the release of the engagement may be manually performed as in the illustrated example, or may be remotely controlled by attaching an actuator. Other configurations and operation modes are the same as those of the fifth embodiment, and thus detailed description is omitted.

FIG. 8 shows a seventh embodiment of the present invention, and shows a normal state. This embodiment differs from the fifth embodiment in that the valve types of the two on-off valves A and B are changed to valve shafts 5a and 5b.
From a swing type provided with a valve body 4a; 4b pivotally supported by the valve body 4 to advance and retreat in the axial direction of the valve shafts 5a; 5b.
a; 4b is replaced with a lift type. In this embodiment as well, the first valve element 4a is configured so as to narrow the intermediate flow path g with the first valve body 4a interposed so as to close most of the cross-sectional area of the intermediate flow path g. Other configurations and operation modes are the same as those of the fifth embodiment, and thus detailed description is omitted.

FIG. 9 shows an eighth embodiment of the present invention, and shows a normal state. In this embodiment, the second valve body 4b in the seventh embodiment is separated from the drive by the driving device D and made independent, and is always urged by the urging member 16 in the valve closing direction. In this case, the second
Normally, the valve body 4b is 1a → 2a → T →
The urging member 16 is pushed by the flow flowing in the path of 2b → 1b.
Keeps the valve open against the urging force of
It is switched by the first valve body 4a and pushed by the flow flowing through the path of 1a → g → 1b, and the urging force of the urging member 16 is also added, so that the closed state can be stably maintained. The first valve element 4a needs to be formed so as to cover most of the cross-sectional area of the intermediate flow path g during normal operation, whereas the second valve element 4b has a cross-sectional area of the intermediate flow path g during normal operation. It is also shown that it is not necessary to form a large part of the element (although such a part can be formed).

Further, in this embodiment, in the driving device D of the seventh embodiment, the pressure chamber j is integrated into the valve box C so as to be always in communication with the main passage, and the first after the emergency occurs. As a mechanism for maintaining the closed state of the on-off valve A, a locking mechanism H is employed instead of operating the on-off valves 33; Other configurations and operation modes are the same as those of the seventh embodiment, and thus detailed description is omitted.

FIG. 10 shows a ninth embodiment of the present invention, showing a normal state. In this embodiment, the flow path structure is changed so that the valve shafts 5a and 5b of the on-off valves A and B in the seventh embodiment are aligned on the same line (the arrangement of the pressure chamber j is also changed accordingly). At the same time, as in the eighth embodiment, the second valve body 4b is separated from and independent of the drive by the drive device D and is always urged by the urging member 16 in the valve closing direction. In the driving device D of this embodiment, as a mechanism for maintaining the closed state of the two on-off valves A and B after the occurrence of an emergency,
Although an example in which the operation of the opening / closing valves 33 and 34 and the locking mechanism H are used together is shown, it is needless to say that only one of the methods may be used. Other configurations and operation modes are the same as those of the above-described embodiments, and thus detailed description is omitted.

FIG. 11 shows a tenth embodiment of the present invention, and shows a normal state. This embodiment is similar to the ninth embodiment.
The driving device D in the embodiment is replaced with a driving device which detects a change in the pressure in the main pipe and operates by detecting a change in the flow rate in the main pipe. Is further provided with a pilot valve device P. The pilot valve device P is connected to the drive device D by the balance between the pressure difference between the front and rear of the orifice 58 provided in the main pipe and the opposing force of the predetermined pressure means. It has a mechanism to control the opening and closing of the pipe pressure water introduction passage.

The pilot valve device P is provided with valve seats 53a and 53b in a valve box 51, and a valve body 54 advances and retreats and the valve seat 5
By opening and closing the opening of 3a; 53b, the supply of the pressurized water to the pressure chamber j of the driving device D is controlled. 52 is a pressure receiving plate, 52s is a sealing member, and 55 is a valve
2 shows a valve shaft to be integrally combined with 2. A pressure chamber m is provided on one side of the pressure receiving plate 52 (side on which the valve shaft 55 is pushed leftward in the drawing).
And a pressure chamber n is formed on the other side, and an urging member 56 for urging the valve shaft 55 rightward in FIG. The acting force can be adjusted by the urging force adjusting section 57, whereby the operating flow rate of the pilot valve device P can be adjusted. The pressure chamber m is communicated with a flow path on the front surface (upstream side) of the orifice 58 by a communication path 61t, and the pressure chamber n is communicated with a flow path on the rear surface (downstream side) of the orifice 58 by a communication path 62t. Both valve seats 53a;
The middle chamber of 53b is a normally open on-off valve 64.
Is communicated with the pressure chamber j by a communication passage 64t provided with The chamber on the opposite side of the valve seat 53b is a communication passage 63t.
And the other chamber across the valve seat 53a is communicated with the atmosphere by a communication passage 65t and is communicated with the pressure chamber j via an on-off valve 65 which is normally closed. I have.

Looking at the operation, normally, the force of the urging member 56 of the pilot valve device P exceeds the pressure difference between the pressure chambers m and n around the pressure receiving plate 52, that is, the pressure difference before and after the orifice 58. , The valve shaft 55 is pushed rightward in FIG.
Closes the opening of the valve seat 53a and opens the opening of the valve seat 53b. For this reason, the main pipe pressure water is supplied to the communication passage 63.
t → the opening of the valve seat 53b → the pressure chamber j in the path of the communication passage 64t
Therefore, in the driving device D, the internal pressure of the pressure chamber j applied to the pressure receiving plate 42 exceeds the force of the urging member 44, and pushes the driving rod 8 to the left in the drawing to open the first on-off valve A. I'm letting it go. Then, the flow of the main pipe passing through the tank T also pushes the second on-off valve B accordingly.

On the other hand, when an emergency situation occurs and the flow rate in the main pipe abnormally increases, the pressure receiving plate 5 of the pilot valve device P
The pressure difference between the two pressure chambers m; n, that is, the pressure difference between the front and rear of the orifice 58, overcomes the force of the urging member 56, so that the valve shaft 55 is pushed leftward in FIG. The part is closed and the opening of the valve seat 53a is opened. As a result, the communication passage 63
t → the main pipe pressure water is prevented from flowing into the pressure chamber j through the path of the opening of the valve seat 53b, while the residual water of the pressure chamber j passes through the communication path 64t → the opening of the valve seat 53a → the communication path 65t. To the atmosphere, and the internal pressure of the pressure chamber j decreases. Therefore, in the driving device D, the force of the urging member 44 overcomes the internal pressure of the pressure chamber j, drives the driving rod 8 rightward in the drawing, closes the first opening / closing valve A, and accordingly the second opening / closing valve. B is also closed, tank T
Is isolated from the mains.

Next, even when the main pipe is drained for repair work and the water pressure itself of the main pipe pressure water disappears, the force of the urging member 44 exceeds the internal pressure of the pressure chamber j, and the driving rod 8 is pushed rightward in the figure, and the tank T remains shut off from the main pipe. At this time, the differential pressure across the orifice 58 disappears, so that only the pilot valve device P returns to the normal state.

During the repair work of the main pipe, the open / close valve 64 which has been open is closed, the open / close valve 65 which has been closed is opened, the pressure chamber j is opened to the atmosphere, and the urging force of the urging member 44 is released. To close the first on-off valve A and keep the tank T shut off from the main pipe. Then, in order to return to the normal state after completion of the repair, the on-off valve 65 is closed again, the on-off valve 64 is opened, the main pipe pressure water is introduced into the pressure chamber j, and the driving rod 8
Is driven to the left in the figure to open the first on-off valve A and, accordingly, the second on-off valve B. With this operation, the emergency cutoff valve device returns to the normal state. In this figure, as a mechanism for holding the closed state of the first on-off valve A after the occurrence of an emergency, on-off valves 64 and 65 are shown.
It is also shown that a locking mechanism H may be used in place of the above operation. Other configurations and operation modes are the same as those in the ninth embodiment, and thus detailed description is omitted.

FIG. 12 shows an eleventh embodiment of the present invention, showing a normal state. This embodiment is based on the first
The driving device D in the zeroth embodiment is replaced with a driving device that detects a change in the flow rate in the main pipe and operates by detecting a change in the pressure in the main pipe. The apparatus P is configured to control the opening and closing of the main pipe pressurized water introduction passage to the driving device D by the balance between the main pipe internal pressure and the opposing force of the predetermined pressure means. That is, the difference from the tenth embodiment is that in the pilot valve device P, one side of the pressure receiving plate 52 (the side that pushes the valve shaft 55 rightward in the drawing) is provided with a main passage 62t by a communication passage 62t. Is formed, and the other side is opened to the atmosphere and the acting force (operating pressure of the pilot valve device P) by the urging force adjusting unit 57 as a predetermined pressure means.
In the driving device D, the urging member 56 capable of adjusting the pressure is adjusted, and the chamber on the opposite side of the pressure chamber j with the pressure receiving plate 42 interposed therebetween is cut off from the atmosphere to be connected to the tank inlet side connection port 2a. The point is that they are always in communication. The pressure receiving area of the pressure receiving plate 42 of the driving device D is equal to the valve body 4 of the first on-off valve A.
It is assumed that the pressure receiving area is set to be larger than the pressure receiving area a.

Looking at the operation, normally, since the internal pressure of the pressure chamber n of the pilot valve device P, that is, the internal pressure of the main pipe exceeds the force of the urging member 56, the valve shaft 55 is pushed rightward in the drawing. The valve element 54 closes the opening of the valve seat 53a and opens the opening of the valve seat 53b. Therefore, the main pipe pressure water flows into the communication passage 63t → the opening of the valve seat 53b → the communication passage 64t.
(The opening / closing valve 64 is normally opened and the opening / closing valve 65 is closed.) Therefore, in the drive device D, the pressure receiving area difference between the pressure receiving plate 42 and the first valve body 4a is reached. The drive rod 8 is pushed to the left in the figure by the front-rear pressure difference accompanying the opening and closing of the first on-off valve A. Then, the flow of the main pipe passing through the tank T also pushes the second on-off valve B accordingly.

On the other hand, if the pressure in the main pipe drops abnormally due to an emergency, the force of the urging member 56 of the pilot valve device P exceeds the internal pressure of the pressure chamber n. Pushed to the left, the valve element 54 closes the opening of the valve seat 53b and opens the opening of the valve seat 53a. As a result, the communication passage 63
t → the main pipe pressure water is prevented from flowing into the pressure chamber j through the path of the opening of the valve seat 53b, while the residual water of the pressure chamber j passes through the communication path 64t → the opening of the valve seat 53a → the communication path 65t. To the atmosphere, and the internal pressure of the pressure chamber j decreases. Therefore, in the driving device D, the force of the urging member 44 overcomes the pressure difference between the pressure receiving plate 42 and the first valve body 4a, and drives the driving rod 8 to the right in the figure, thereby causing the first on-off valve A to move. The tank is closed and the second on-off valve B is also closed, so that the tank T is shut off from the main pipe.

Next, even when the main pipe is drained for repair work and the water pressure of the main pipe pressure water is lost, the urging member 4
Due to the force of 4, the drive rod 8 is pushed rightward in the figure, and the tank T remains disconnected from the main pipe. At this time, in the pilot valve device P, the valve shaft 55 remains pressed to the left in the drawing.

During the repair work of the main pipe, the on-off valve 64 which has been open is closed, the on-off valve 65 which has been closed is opened, the pressure chamber j is opened to the atmosphere, and the urging force of the urging member 44 is released. To close the first on-off valve A and keep the tank T shut off from the main pipe. Then, in order to return to the normal state after completion of the repair, the on-off valve 65 is closed again, the on-off valve 64 is opened, the main pipe pressure water is introduced into the pressure chamber j, and the driving rod 8
Is driven to the left in the figure to open the first on-off valve A and, accordingly, the second on-off valve B. With this operation, the emergency cutoff valve device returns to the normal state. Other configurations and operation modes are the same as those of the tenth embodiment, and thus detailed description is omitted.

As described above, the emergency shut-off valve device of the present invention produces an epoch-making operation and effect, but furthermore, within the scope of the present invention, various structural changes are made or the prior art is used. It is possible to meet implementation requirements.

For example, as the driving device D, FIGS. 6 to 12 particularly show the driving device utilizing the water pressure in the main pipe, but the present invention is not limited to this. For example, an electric type, a pneumatic type, a hydraulic type, or the like may be appropriately selected. If it is desired to drive slowly, a braking device such as a damper or a dashpot may be appropriately provided. As for the detector S, an electrical sensor, a mechanical sensor, or the like may be appropriately selected, and the installation location of the detector S may be on the upstream side or the downstream side of the main pipe. Regarding the locking mechanism H, a conventional technique such as an electric or mechanical locking device for releasing the first on-off valve A and the second on-off valve B at a predetermined position, and a means for releasing the lock are used. You may use together.

The method of sealing each seal portion may be appropriately selected according to the specification, such as using an O-ring, packing, a seal ring, a diaphragm, a bellows, or the like, or leaving a metal touch. Regarding each biasing member, a coil spring is illustrated in each drawing, but other shapes of springs, other elastic members, or using gravity, or applying a pressure, a hydraulic device, etc. Good.

The valve types of the first on-off valve A and the second on-off valve B are exemplified by a swing type and a lift type.
Needless to say, the technical concept of the present invention can be applied to other valve types (for example, a ball valve and a butterfly valve). In addition, the shape of the contact surface between the valve body and the valve seat may be cone-shaped or curved, or a comb-shaped projection may be provided on the valve body or the valve seat to prevent hunting when the amount of water is small immediately before closing the valve. Conventional technology may be used. With respect to the swing type on-off valves A and B shown in FIGS. 1 to 7, the valve bodies 4a and 4b are divided and connected to two sections of a valve section and an arm section, and the connection section allows a slight movement. As a result, it is possible to further improve the adhesion to the valve seats 3a;

Open / close valves 31; 32 provided in each communication passage;
33; 34; 35; 64; 65 can be appropriately selected, for example, a gate valve, a ball valve, a ball valve, a lift valve, a cock, etc., as long as they have an opening / closing function. is there. Also, for example, the on-off valves 33 and 34 in FIG. 10 and the on-off valves 6 in FIGS.
4, 65, etc. may be integrated into a three-way valve type, and an actuator may be appropriately provided for remote control or automation.

The main body of the emergency shut-off valve device of each embodiment, and the valve body, valve seat,
The arrangement order (positional relationship) of the components such as the pressure receiving plate, the pressure chamber, and the communication passage piping is an example, and is not limited to this arrangement order. In addition, various design changes can be made within the scope of the present invention, and the present invention is not limited to the above embodiments.

[0061]

As described above, the present invention can drastically solve the technical problems of the conventional emergency shut-off valve device by a simple and rational structure, and automatically and reliably switch the flow path. And the on-off valve part for switching the flow path,
The open / close valve has a tendency to automatically maintain the position by skillfully utilizing the flow force at that time, regardless of the open / close position, and requires only a small driving force. The valve closing biasing means and the driving device can be formed compactly, easy to design, manufacture and maintain, the cost is low, and furthermore, it has high sealing performance by easy sealing means, and even if it is large, A high-performance and economical emergency shut-off valve device which does not cause a problem is obtained, and the remarkable effect of the implementation is extremely large as compared with the prior art.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a first embodiment of an emergency shutoff valve device according to the present invention, showing a normal state.

FIG. 2 is a longitudinal sectional view of the first embodiment of the emergency cutoff valve device of the present invention, showing an emergency state.

FIG. 3 is a longitudinal sectional view of a second embodiment of the emergency cutoff valve device of the present invention, showing a normal state.

FIG. 4 is a side view (partial longitudinal sectional view) of a third embodiment of the emergency cutoff valve device of the present invention, showing a normal state.

FIG. 5 is a vertical sectional view of a fourth embodiment of the emergency cutoff valve device of the present invention, showing a normal state.

FIG. 6 is a vertical sectional view of a fifth embodiment of the emergency cutoff valve device of the present invention, showing a normal state.

FIG. 7 is a longitudinal sectional view of a sixth embodiment of the emergency cutoff valve device of the present invention, showing a normal state.

FIG. 8 is a vertical sectional view of a seventh embodiment of the emergency cutoff valve device of the present invention, showing a normal state.

FIG. 9 is a vertical sectional view of an emergency shut-off valve device according to an eighth embodiment of the present invention, showing a normal state.

FIG. 10 is a longitudinal sectional view of a ninth embodiment of the emergency cutoff valve device of the present invention, showing a normal state.

FIG. 11 is a longitudinal sectional view of a tenth embodiment of the emergency cutoff valve device of the present invention, showing a normal state.

FIG. 12 is a vertical sectional view of an emergency shut-off valve device according to an eleventh embodiment of the present invention, showing a normal state.

FIG. 13 is a side view showing an example of a conventional emergency shutoff valve device.

FIG. 14 is a longitudinal sectional view showing an example of a conventional emergency shutoff valve device.

[Explanation of symbols]

A: First on-off valve B: Second on-off valve C: Valve box D
... Drive device H ... Locking mechanism P ... Pilot valve device S ... Detector T ... Tank g ... Intermediate flow path i ... Pressure chamber j ... Pressure chamber m ... Pressure chamber n ... Pressure chamber 1a ... Main pipe upstream connection port 1b ... Main pipe downstream connection port 2a ... Tank inlet connection port 2b ... Tank outlet connection port 3a ... First valve seat 3b ... Second valve seat 4a ... First valve body 4b ... Second valve body 5a ... First valve Shaft 5b: second valve shaft 6a: receiving part
6b ... receiving part 7a ... link arm 7b ... link arm 8 ... drive rod 9 ... locking part 10 ... connecting member 11
... Connecting member 12 ... Handle shaft 12t ... Screw part 13 ... Handle 14 ... Biasing member 15 ... Bearing 16 ... Biasing member 17 ... Counter weight 21 ... Cylinder part 22 ... Pressure receiving plate 23 ... Locking pin 24 ... Biasing member 25 ... biasing force adjusting section 31 ... on-off valve 31t ... communication passage 32 ... on-off valve
33 ... On-off valve 33t ... Communication passage 34 ... On-off valve 35 ... On-off valve
35t communication path 41 cylinder part 42 pressure receiving plate 44 urging member 45 urging force adjusting part 51 pilot valve box 52 pilot pressure receiving plate
52s: Seal member 53a: Pilot valve seat 53b: Pilot valve seat
54 pilot valve element 55 pilot valve shaft 56 urging member 57 urging force adjuster 58 orifice 61 t communication path 62 t communication path 63 t communication path 64 opening / closing valve 64 t opening / closing valve 65 opening / closing valve
65t communication path 71 emergency stop valve 72 emergency stop valve 73 emergency release valve 81 four-way butterfly valve 82 valve element 83 valve seat 84 valve seat

Claims (11)

[Claims] An intervening tank is provided between a tank provided in parallel with the main pipe and the main pipe, and normally, the fluid on the upstream side of the main pipe flows to the downstream side of the main pipe via the tank to provide an emergency. Sometimes, the fluid in the tank is cut off from the main pipe and the fluid on the upstream side of the main pipe flows directly to the downstream side of the main pipe without passing through the tank.
In an emergency shut-off valve device for switching a flow path, a valve box includes a main pipe upstream connection port, a main pipe downstream connection port, a tank inlet side connection port, and a tank outlet side connection port. The port and the main pipe downstream connection port are communicated via an intermediate flow path, the main pipe upstream connection port and the tank inlet side connection port are communicated via a first on-off valve, and the main pipe downstream connection port is connected to the main pipe downstream connection port. The tank outlet side connection port is communicated via a second opening / closing valve, and the first opening / closing valve and the second opening / closing valve are normally operated together in a direction away from the tank to normally open the tank inlet side connection port and the tank outlet side. Each of the connection ports is opened, and in an emergency, both are operated in a direction toward the tank to close each of the tank inlet-side connection port and the tank outlet-side connection port, and the first on-off valve is connected to the tank inlet-side connection port. When the valve is opened, the valve element of the first on-off valve is interposed in the Emergency shutoff valve apparatus characterized in that it is configured to narrow the road. 2. The emergency shut-off valve device according to claim 1, wherein both the first on-off valve and the second on-off valve are opened and closed by a driving device. 3. The emergency shut-off according to claim 1, wherein the first on-off valve is driven to be opened and closed by a driving device, and the second on-off valve is always urged in a valve closing direction. Valve device. 4. An urging means for urging the on-off valve in one direction, and an operating means for forcibly moving the on-off valve in a direction opposite to the urging direction of the urging means. The emergency shutoff valve device according to claim 2 or 3, further comprising: 5. The apparatus according to claim 2, wherein the drive device opens and closes the on-off valve in accordance with an increase or decrease in the main line fluid pressure at a predetermined pressure value. The emergency shut-off valve device according to claim 1. 6. The open / close valve according to claim 2, wherein the drive device opens and closes the on-off valve in accordance with an increase or decrease in the flow rate of the main pipe fluid at a predetermined flow rate value. The emergency shut-off valve device according to claim 1. 7. The driving device includes a pressure receiving plate hermetically and movably accommodated in a container, wherein the main pipe fluid pressure acting before and after the pressure receiving plate and an opposing force between a predetermined pressure means and a predetermined pressure means. The emergency shutoff valve device according to any one of claims 2 to 6, wherein the on / off valve is driven to open and close by balance. 8. The pilot valve device is attached to the driving device, and the pilot valve device applies the main pipe fluid pressure to the driving device by balancing the opposing force of the main pipe fluid pressure and a predetermined pressure means. The emergency shutoff valve device according to claim 7, wherein opening and closing control of the introduction passage is performed. 9. A pilot valve device is attached to the driving device, and the pilot valve device is driven by a balance between a front-rear differential pressure of an orifice provided in the main pipe and an opposing force of a predetermined pressure means. The emergency shutoff valve device according to claim 7, wherein an opening / closing control of the main fluid pressure introduction passage to the device is performed. 10. The emergency shutoff valve device according to claim 1, further comprising a locking mechanism for holding and releasing said open / close valve at a predetermined open / close position. 11. The main body fluid pressure increasing and decreasing at a predetermined pressure value, the main fluid flow increasing and decreasing at a predetermined flow rate value, and presence or absence of an emergency state detection signal by a detector. The emergency shut-off valve device according to claim 10, wherein a holding / release operation of the predetermined position of the on-off valve is performed in accordance with any of the above.