Water-submersion detection cutoff device

Abstract

To provide a submersion detection cutoff device that is designed to, when submerged due to flood damage or the like, make only a predetermined pressure associated with submersion act on a diaphragm to enable a smooth stroke, and thus exhibits a function of cutting off a gas pipe satisfactorily.SOLUTION: A housing 10 that constitutes a second chamber K2 comprises an orifice O that communicates with the outside and the second chamber K2, where an inner diameter of the orifice O is set to such a diameter that when a water level due to submersion is higher than a height position of the orifice O in a vertical direction, water can enter the second chamber K2 from the outside when a head pressure applied to the orifice O exceeds an internal pressure of the second chamber K2, and water is prohibited from entering the second chamber K2 from the outside when the water head pressure applied to the orifice O is equal to or lower than the internal pressure of the second chamber K2.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a submersion detection and shutoff device that can shut off a gas pipe through which gas flows when the gas pipe is submerged in water. [Background technology]

[0002] Conventionally, as shown in Patent Document 1, there has been known an emergency shutoff device capable of emergency shutoff of a fluid flow pipe through which a fluid flows. This emergency shutoff device divides the inside of a housing into a first chamber and a second chamber by a diaphragm, provides a pressure setting spring in the second chamber for pressing the diaphragm from the second chamber side to the first chamber side, and is configured to be able to introduce fluid flowing through the fluid flow pipe into the first chamber. The emergency shutoff device is configured to be able to perform emergency shutoff of the fluid flow pipe and release the emergency shutoff by triggering the diaphragm to move along the biasing direction of the pressure setting spring in response to the pressure of the fluid flowing into the first chamber (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 09-014492 Summary of the Invention [Problem to be solved by the invention]

[0004] An emergency shutoff device equipped with a diaphragm as described above may be installed with the pressure-receiving surface of the diaphragm aligned in a direction other than horizontal (for example, vertical) due to installation space, etc. In this case, a fluid such as water that has flowed into the first chamber is subjected to a higher pressure on the pressure-receiving surface of the diaphragm the lower it is in the depth direction, and pressure is not applied evenly to the entire pressure-receiving surface of the diaphragm, so that the diaphragm does not smoothly stroke in the biasing direction of the pressure setting spring, and there are cases in which the shutoff function cannot be satisfactorily performed.

[0005] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a submersion detection shut-off device which can be designed to allow a smooth stroke when submerged due to flooding or the like by applying only a specified pressure associated with submersion to the diaphragm, thereby enabling the device to perform a good shut-off function for gas piping. [Means for solving the problem]

[0006] In order to achieve the above object, the submersion detection and cutoff device comprises: A submersion detection and shutoff device that can shut off a gas pipe through which gas flows when the gas pipe is submerged in water, and its characteristic configuration is as follows: a valve body that opens and closes the gas piping, a diaphragm, a pressure setting spring that can bias the diaphragm from the first chamber side to the second chamber side with respect to a housing that is partitioned into a first chamber and a second chamber by the diaphragm, and a mechanism that shuts off the valve body by the stroke of the diaphragm, The housing constituting the second chamber includes an orifice that communicates between the outside and the second chamber, an inner diameter of the orifice is set to a diameter that allows water to enter the second chamber from the outside when the head pressure applied to the orifice exceeds the internal pressure of the second chamber in a case where the water level due to submersion is higher than the vertical height position of the orifice, and prohibits water from entering the second chamber from the outside when the head pressure applied to the orifice is equal to or lower than the internal pressure of the second chamber; an atmospheric pressure equalizing tube having one end connected to the communication hole provided in the housing constituting the first chamber and an atmospheric vent hole at the other end is connected, the atmospheric vent hole being located above the orifice; The atmospheric vent hole is provided at a position higher than the estimated flood water level set in a hazard map for the installation position of the housing.

[0007] According to the above characteristic configuration, when the submersion detection cutoff device according to the present invention is submerged due to flood damage, etc., even if the head pressure applied to the orifice becomes almost equal to the internal pressure of the second chamber, the surface tension of the water can be prevented from replacing the internal gas with water, making it possible to design the diaphragm to be subjected to only the head pressure of the orifice. If the diaphragm strokes, water will be allowed to enter, but by adopting a configuration in which a reservoir tank is provided in communication with the housing, for example, the invaded water will accumulate in the reservoir tank, thereby realizing a configuration that does not adversely affect the pressure acting on the diaphragm. Furthermore, according to the above characteristic configuration, even if flood damage occurs, if the flood water level is below the estimated flood water, water will not enter the first chamber, and the pressure inside the first chamber can be set to atmospheric pressure, so the water submersion detection and shutdown function can be performed well.

[0008] Further characteristic configurations of the water submersion detection cutoff device include: a discharge port that discharges the water that has flowed into the second chamber through the orifice from the second chamber, and a storage tank that stores the water discharged from the discharge port, The discharge port is provided vertically below the orifice.

[0009] According to the above characteristic configuration, for example, when the submersion detection shutoff device of the present invention is submerged, the head pressure applied to the orifice can be applied to the second chamber, the increase in pressure in the second chamber displaces the diaphragm, and the displacement of the diaphragm brings the valve body into a closed state, thereby achieving good submersion shutoff. At this time, water flows into the second chamber from the orifice located vertically above, and the water is discharged from an outlet located vertically below the orifice and stored in the storage tank, so water does not remain in the second chamber. This makes it possible to prevent different water pressures from being applied to the diaphragm in the vertical direction. This makes it possible to apply the internal pressure of the second chamber evenly to the entire pressure-receiving surface of the diaphragm even when submerged in water. This effect is well exhibited regardless of the angle of the pressure-receiving surface of the diaphragm relative to the horizontal direction.

[0010] In order to achieve the above-mentioned effects, for example, it is preferable that the inner diameter of the orifice is set to be equal to or greater than 3 mm and equal to or less than 7 mm.

[0011] Further characteristic configurations of the water submersion detection cutoff device include: The diaphragm is disposed such that the pressure receiving surface is aligned along a direction intersecting the horizontal direction.

[0012] In the submersion detection and blocking device having the characteristic configuration described so far, even if the pressure-receiving surface of the diaphragm is installed along a cross direction (e.g., including the vertical direction) that intersects the horizontal direction, the submersion blocking function can be performed well, so various installation conditions can be tolerated and the degree of freedom in installation can be improved.

[0013] Further characteristic configurations of the water submersion detection cutoff device include: The set pressure used to bias the diaphragm by the pressure setting spring is set to be smaller than the head pressure derived from the difference between the expected flooding water level set in a hazard map at the installation position of the housing and the vertical height position of the orifice.

[0014] As in the above characteristic configuration, by setting the set pressure used by the pressure setting spring to bias the diaphragm to a value smaller than the head pressure derived from the difference between the expected flooding water level set in the hazard map at the installation position of the housing and the vertical height position of the orifice, when the expected flooding water level expected in the event of a flood is reached, the diaphragm is displaced by increasing the pressure in the second chamber, the valve body is transitioned to a closed state, and the gas piping is successfully shut off by submersion. [Brief description of the drawings]

[0015] [Figure 1] 1 is a schematic diagram of a water submersion detection and interruption device according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The submersion detection shutoff device 100 according to an embodiment of the present invention is designed to allow a smooth stroke when submerged due to flooding or the like by applying only a specified pressure associated with submersion to the diaphragm, thereby enabling the device to perform a good gas piping shutoff function. Hereinafter, a water submersion detection and interruption device 100 according to an embodiment will be described with reference to the drawings.

[0017] 1, the submersion detection cutoff device 100 according to this embodiment is configured by modifying a normally open direct acting governor, and includes a valve body Va that can be seated on a valve seat Vb formed inside a gas pipe L1 through which gas (e.g., city gas 13A) flows, a valve shaft Vc that is provided along the opening / closing movement direction of the valve body Va, and a diaphragm A that is connected to the valve shaft Vc. The valve shaft Vc is provided with a seal member 12 between it and the gas pipe L1, and is disposed so as to be slidable relative to the gas pipe L1. Incidentally, the diaphragm A is disposed so that the pressure-receiving surface is aligned along a direction intersecting the horizontal direction (in this embodiment, the vertical direction along the arrow Z). Also, the valve axis Vc is disposed along the horizontal direction.

[0018] The diaphragm A divides the interior of the housing 10 into a first chamber K1 and a second chamber K2. The first chamber K1 is provided with a pressure setting spring S which urges the diaphragm A from the first chamber K1 to the second chamber K2 with one end abutting against the diaphragm A and the other end abutting against a saucer Sa provided in the first chamber K1. The saucer Sa is configured to be movable in a displacement direction (arrow Y direction in FIG. 1) by rotating while screwing into a female screw portion 10a formed on the inner wall of the first chamber K1, and the urging force of the pressure setting spring S on the diaphragm A is adjusted by moving the saucer Sa in the displacement direction. The housing 10 constituting the first chamber K1 is provided with a communication hole 20b, and an atmospheric pressure equalizing tube 20 having one end connected to the communication hole 20b and an atmospheric vent hole 20a located above the communication hole 20b is connected to the communication hole 20b. With this configuration, the first chamber K1 is maintained at atmospheric pressure. Here, the atmospheric vent hole 20a of the atmospheric equalization pipe 20 is located above the orifice O and is provided at a position (X3 in Figure 1) higher than the expected flood water level (X2 in Figure 1) set in the hazard map at the installation position of the housing 10 (the cut-off position where the gas piping L1 is cut off).

[0019] Furthermore, the housing 10 constituting the second chamber K2 has an orifice O that connects the second chamber K2 to the outside, an outlet C1 that discharges water that has flowed into the second chamber K2 via the orifice O from the second chamber K2, and a storage tank C that stores the water discharged from the outlet C1. The outlet C1 is provided vertically below the orifice O. More preferably, the outlet C1 is provided at the lowest position in the vertical direction of the housing 10 constituting the second chamber K2.

[0020] In the above configuration, when the orifice O is in a natural state where it is not submerged, the position of the receiving tray Sa is adjusted in the displacement direction and the biasing force of the pressure setting spring S is set so that the valve body Va is in an open state (preferably, a fully open state).

[0021] Furthermore, the inner diameter X4 of the orifice O is set to a diameter that allows water to enter the second chamber K2 from the outside when the head pressure on the orifice O exceeds the internal pressure of the second chamber K2 in a case where the submerged water level (height from the ground G to the water surface: X2) is higher than the vertical height position of the orifice O (height position from the ground G: X1) and prohibits water from entering the second chamber K2 from the outside when the head pressure on the orifice O is equal to or lower than the internal pressure of the second chamber K2. Specifically, the inner diameter X4 of the orifice O is set to 3 mm or more and 7 mm or less. Here, the head pressure means the water pressure acting on the orifice O when the orifice O is submerged in water. In particular, even if the head pressure applied to the orifice O becomes almost equal to the internal pressure of the second chamber K2, the surface tension of the water can be prevented from replacing the internal gas (air) with water, making it possible to design the diaphragm A to be subjected to only the head pressure of the orifice O. If the diaphragm A strokes, water will be allowed to enter, but the invading water will accumulate in the reservoir C and will not adversely affect the pressure acting on the diaphragm A.

[0022] Incidentally, it is preferable that the inner diameter X4 of the orifice O allows water to enter the second chamber K2 from the outside and prevents gas (air in this embodiment) in the second chamber K2 from flowing out to the outside when the water level due to submersion (height from the ground G to the water surface: X2) is higher than the vertical height position of the orifice O (height position from the ground G: X1) and the head pressure applied to the orifice O exceeds the internal pressure of the second chamber K2. As a result, when water enters the second chamber K2 and the gas in the second chamber K2 does not flow out to the outside, the pressure in the second chamber K2 increases by the volume of the water that has flowed into the second chamber K2, so that the diaphragm A is pressed from the second chamber K2 side to the first chamber K1 side, and the valve body Va transitions from the open state to the closed state.

[0023] In this embodiment, the set pressure used to bias the diaphragm A by the pressure setting spring S is set to be smaller than (preferably the same as) the head pressure derived from the difference between the expected flooding water level (X2 in Figure 1) set in the hazard map at the installation position of the housing 10 and the vertical height position of the orifice O (X1 in Figure 1). As a result, in the event of a flood exceeding at least the anticipated flood water level, water will enter the second chamber K2, causing the diaphragm A to displace against the biasing force of the pressure setting spring S, and the valve body Va will transition to a closed state. Incidentally, the internal volume of the storage tank C is determined based on the head pressure and the pressure of the second chamber K2 before the second chamber K2 is flooded with water. More specifically, the internal volume of the storage tank C is set to a volume that is sufficiently larger than the total volume of water that will flood in when water floods the second chamber K2, the internal pressure after the pressure of the second chamber K2 is increased becomes equal to the head pressure, and the flooding of water stops.

[0024] [Another embodiment] (1) In the above embodiment, the diaphragm A has a configuration example in which the pressure-receiving surface is provided along the vertical direction. However, the pressure-receiving surface may be provided along a direction intersecting the horizontal direction. In other words, the pressure receiving surface of the diaphragm A may be provided at any angle as long as the water that has flowed from the orifice O into the second chamber K2 has an inclination that leads to the storage tank C.

[0025] (2) In the above embodiment, the inner diameter X4 of the orifice O is set to 3 mm or more and 7 mm or less. However, the present invention is not limited to this value. For example, a configuration may be adopted in which the inner diameter X4 of the orifice O is set to be greater than 5 mm, and a filter having a predetermined mesh size is disposed in the orifice O.

[0026] (3) In the above embodiment, the height position of the atmospheric vent hole 20a of the atmospheric equalizing pipe 20 from the ground G and the set pressure of the pressure setting spring S were set based on the expected water level of flooding at the installation position of the submersion detection and blocking device 100 on the hazard map. As another configuration example, the height position of the atmospheric vent hole 20a of the atmospheric equalization pipe 20 from the ground G and the set pressure by the pressure setting spring S may be set based on the water level obtained by multiplying the expected flood water level according to the hazard map by a predetermined setting adjustment rate.

[0027] (4) In the above embodiment, the submersion detection and shutoff device 100 may be configured to include a valve body Va that can seat on a valve seat Vb formed inside a gas pipe L1 through which a gas (e.g., city gas 13A) flows, a diaphragm A, a pressure setting spring S that can urge the diaphragm A from the first chamber K1 side to the second chamber K2 side with respect to a housing 10 partitioned by the diaphragm A into a first chamber K1 and a second chamber K2, and a mechanism (not shown) that shuts off the valve body Va by stroking the diaphragm A. That is, the valve closing function may be performed by a spring (not shown) dedicated to the valve closing function, and the stroke of the diaphragm A may be the operation trigger (for example, to release the latch).

[0028] (5) In the above embodiment, the atmospheric pressure equalizing tube 20 has the atmospheric vent hole 20a located above the communication hole 20b. However, the present invention is not limited to this configuration.

[0029] Furthermore, the configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, provided that no contradiction arises. Furthermore, the embodiments disclosed in this specification are merely examples, and the embodiments of the present invention are not limited thereto, and can be appropriately modified within the scope that does not deviate from the purpose of the present invention. [Industrial Applicability]

[0030] The submersion detection shutoff device of the present invention can be designed so that when it becomes submerged due to a flood or the like, only the specified pressure associated with submersion acts on the diaphragm, allowing it to stroke smoothly, and can be effectively used as a submersion detection shutoff device that can effectively perform the shutoff function of gas piping. [Explanation of symbols]

[0031] 10: Housing 20: Atmospheric pressure equalizing tube 20a: Atmospheric opening hole 20b:Communication hole 100: Water-submersion detection cutoff device A: Diaphragm C:Storage tank K1: Room 1 K2: 2nd room L1: Gas piping O: Orifice S: Pressure setting spring Va: Valve body Vb: Valve seat Vc: Valve stem X4: Inner diameter

Claims

1. A submersion detection and shutoff device capable of shutting off a gas pipe through which gas flows when the gas pipe is submerged, a valve body that opens and closes the gas piping, a diaphragm, a pressure setting spring that can bias the diaphragm from the first chamber side to the second chamber side with respect to a housing that is partitioned into a first chamber and a second chamber by the diaphragm, and a mechanism that shuts off the valve body by the stroke of the diaphragm, The housing constituting the second chamber includes an orifice that communicates between the outside and the second chamber, an inner diameter of the orifice is set to a diameter that allows water to enter the second chamber from the outside when a water level due to submersion is higher than a vertical height position of the orifice and a head pressure applied to the orifice exceeds an internal pressure of the second chamber, and prohibits water from entering the second chamber from the outside when the head pressure applied to the orifice is equal to or lower than the internal pressure of the second chamber; an atmospheric pressure equalizing tube having one end connected to the communication hole provided in the housing constituting the first chamber and an atmospheric vent hole at the other end is connected, the atmospheric vent hole being located above the orifice; The atmospheric vent hole is provided at a position higher than the estimated flood water level set in a hazard map for the installation position of the casing.

2. a discharge port that discharges the water that has flowed into the second chamber through the orifice from the second chamber, and a storage tank that stores the water discharged from the discharge port, The submersion detection and cutoff device according to claim 1 , wherein the outlet is provided vertically below the orifice.

3. 3. The water submersion detection and cutoff device according to claim 1, wherein an inner diameter of the orifice is set to be equal to or greater than 3 mm and equal to or less than 7 mm.

4. 4. The water submersion detection cutoff device according to claim 1, wherein the diaphragm is disposed so that a pressure receiving surface thereof is aligned along a direction intersecting a horizontal direction.

5. A submersion detection and blocking device as described in any one of claims 1 to 4, wherein the set pressure for biasing the diaphragm by the pressure setting spring is set to be smaller than the water head pressure derived from the difference between the expected water level of flooding set in a hazard map at the installation position of the housing and the vertical height position of the orifice.

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