Pressure reducing valve used in fire-extinguishing pressure reducing device

Abstract

To improve installation efficiency by preventing pressure fluctuation on each fire-extinguisher side even with a small number of installations, and to surely secure safety during operation of the fire extinguisher.SOLUTION: A pressure reducing valve V is used in a fire-extinguishing pressure reducing device for adjusting water pressure on a fire-extinguisher side, the fire-extinguishing pressure reducing device being provided in a main water supply pipe of fire extinguishing equipment in which a plurality of branch water supply pipes are arranged in the main water supply pipe for supplying water from a water tank by means of a height difference. The pressure reducing valve V includes: a pilot conduit 40 provided with a body 10 having a primary chamber 17 and a secondary chamber 18 and configured to open a valve body 21 by reducing pressure in an operation camber 33 of an operation diaphragm 30 when water pressure in the secondary chamber 18 becomes equal to or lower than a reference pressure; and a conduction passage 60 configured to guide water in the primary chamber 17 to the operation chamber 33. A bypass pipe 101 composing a bypass conduit 100 allowing communication between the operation chamber 33 and the secondary chamber 18 and a manual opening / closing valve 102 for opening / closing the bypass pipe are attached to an outer side of the body 10.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a pressure reducing valve used in a fire-fighting pressure reducing device provided in a fire extinguishing system, mainly in a high-rise building, equipped with fire extinguishing appliances such as a sprinkler system, a fire water supply pipe connection part, and an indoor fire hydrant. [Background technology]

[0002] Conventionally, in fire extinguishing systems for high-rise buildings, fire extinguishing equipment such as sprinkler systems, fire water pipe connections, indoor fire hydrants, and outdoor fire hydrants are installed on required floors, and these fire extinguishing equipment are installed on each of the branch water pipes, which are connected to a main water pipe that pumps water from a water tank on the lower floor. In this fire extinguishing system, if water is released from each fire extinguishing equipment at the same time, pressure fluctuations become large and the water supply state becomes uneven, so a fire pressure reducing device is installed to adjust the pressure, and a pressure reducing valve used for this is installed on each branch supply pipe to prevent pressure fluctuations (for example, as described in JP 2005-87306 A). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP2005-87306A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in this conventional fire extinguishing system, the pressure reducing valve used in the fire extinguishing pressure reducing device is provided for each branch water pipe, and therefore, as many pressure reducing valves must be provided as there are branch water pipes, the number of pressure reducing valves increases, which leads to problems such as the trouble of installation becoming more complicated, the cost increasing, and the installation efficiency becoming poor. In addition, when the pressure reducing valve is installed or when water supply to the fire extinguishing device starts or is in the middle of being supplied, air may get mixed in, which may cause the valve to malfunction. The present invention has been made in consideration of the above points, and has an object to provide a pressure reducing valve for use in a fire extinguishing pressure reducing device that can suppress pressure fluctuations on the side of each fire extinguishing appliance even when a small number of appliances are installed in a fire extinguishing system, thereby improving installation efficiency, and that can reliably bleed air during installation and reliably ensure safety when the fire extinguishing appliance is operated. [Means for solving the problem]

[0005] In order to achieve the above object, the pressure reducing valve used in the fire extinguishing pressure reducing device of the present invention is provided in a fire extinguishing system in which a plurality of branch water supply pipes are arranged on a main water supply pipe that supplies water from a water tank due to a difference in height, and a fire extinguishing device is provided on each branch water supply pipe, and the fire extinguishing pressure reducing device is provided with a main pipe constituted by a part of the main water supply pipe and a pressure reducing valve interposed in the main pipe, a main body having an inlet and an outlet and forming a flow path through which water flows; a partition wall provided in the main body and dividing the flow path of the main body to form a primary chamber on the inlet side and a secondary chamber on the outlet side; a valve body for opening and closing a valve port provided in the partition wall; an actuating diaphragm provided in the main body and linked to the valve body for opening and closing the valve body by pressure in a working chamber; a pilot pipe provided between the secondary chamber and the working chamber for reducing the pressure in the working chamber and opening the valve body via the actuating diaphragm when the water pressure in the secondary chamber falls below a reference pressure; and a conduit for directing water from the primary chamber to the working chamber and communicating with the pilot pipe line, A bypass pipeline is provided to connect the working chamber and the secondary chamber, and a bypass pipe constituting a part of the bypass pipeline and a manual opening and closing valve for opening and closing the bypass pipeline are attached to the outside of the main body.

[0006] Thus, when the pressure reducing valve is installed, the water tank side is connected to the inlet and the fire extinguishing appliance side is connected to the outlet at the required points of the main water supply pipe. Then, so-called water filling is performed. In this case, for example, the fire extinguishing appliance side is set so that water flows, and water is supplied from the water tank by head, and in this state, the open / close valve of the bypass pipe is opened. As a result, water flows into the primary chamber and is guided to the working chamber through the guide passage, and further, the water that has flowed into the working chamber flows through the bypass pipe to the secondary chamber and is discharged. In this case, water flows from the working chamber to the secondary chamber side, so that the working chamber is in a reduced pressure state, and therefore the valve body is opened via the operating diaphragm, so that the water that has flowed into the primary chamber flows through the valve port into the secondary chamber and is discharged, and water filling is performed. In addition, in this case, water flows from the working chamber to the secondary chamber side, and air in the working chamber is released accordingly. Therefore, air can be bled by simply operating the opening and closing valve, which is easy to operate and allows air to be bled easily and reliably when filling the tank with water during installation. This also applies to filling the tank with water during maintenance, for example. Once filling the tank with water is complete, the water flow from the fire extinguishing device side is stopped and the opening and closing valve of the bypass pipe is closed to prepare for an emergency.

[0007] In addition, in the event of an emergency such as a fire, water will begin to flow on the fire extinguishing appliance side, causing the pressure in the secondary chamber of the pressure reducing valve to drop, and when the water pressure in the secondary chamber falls below the reference pressure, the pilot line will function to reduce the pressure in the working chamber and open the valve body via the working diaphragm. As a result, water from the primary chamber will flow through the valve port to the secondary chamber, supplying water to the fire extinguishing appliance. In this case, the opening of the valve body is adjusted by the function of the pilot line, so the pressure on the fire extinguishing appliance side is adjusted and pressure fluctuations are suppressed. In addition, air is reliably bled, so operation can be performed stably and safety can be ensured.

[0008] When supplying water to this fire extinguishing appliance, there is a risk of malfunction in the opening and closing of the valve body of the pressure reducing valve, but in the unlikely event that the outflow of water from the fire extinguishing appliance stops, the on-off valve of the bypass pipe is opened. As a result, as described above, water flows from the working chamber to the secondary chamber, causing the working chamber to be in a reduced pressure state, and therefore the valve body is opened via the working diaphragm, so that the water that has flowed into the primary chamber flows through the valve port into the secondary chamber and is discharged, and is forcibly supplied to the fire extinguishing appliance. Therefore, although the function of the pressure reducing valve is sacrificed, the water supply is secured, and safety can be guaranteed.

[0009] In addition, since the bypass pipe and on-off valve are attached to the outside of the main body of the pressure reducing valve, for example, when a bypass pipe is provided in the main water supply pipe across the pressure reducing valve, the installation work is required and becomes complicated, but in comparison, the pressure reducing valve is more compact and the installation efficiency can be improved.

[0010] In this way, according to the present invention, pressure fluctuations on the fire extinguishing appliance side can be suppressed by installing the pressure reducing valve on the main water supply pipe that supplies water from the water tank due to the difference in height, so there is no need to install a pressure reducing valve on each branch water supply pipe as in the past, and pressure fluctuations on each fire extinguishing appliance side can be suppressed with a small number of installations, improving installation efficiency. In addition, air can be reliably bled when the pressure reducing valve is installed, and safety can be guaranteed when the fire extinguishing appliance is activated.

[0011] In the present invention, if necessary, the main pipe of the fire extinguishing pressure reducing device is configured to include a main pipe and one or more bypass pipes connected in parallel to the main pipe, and the main body is connected between a pair of stop valves connected to the main pipe in the middle of the main pipe, and the main body is connected between a pair of stop valves connected to the bypass pipe in the middle of the bypass pipe, so that the main pipe and the bypass pipe are interposed therein. That is, in the fire extinguishing pressure reducing device, the pressure reducing valve can be used by being interposed both in the main pipe and in the bypass pipe connected in parallel thereto. When there are two or more bypass pipes, the pressure reducing valve is interposed in each of them.

[0012] Thus, when so-called water filling, for example, the stop valves in the main main pipe and the bypass main pipe are opened, water is set to flow on the fire extinguishing appliance side, water is supplied from the water tank by head, and in this state, the open / close valve of the bypass pipe is opened. As a result, as in the above, water flows into the primary chamber and is guided to the working chamber through the guide passage, and further, the water that has flowed into the working chamber flows through the bypass pipe to the secondary chamber and is discharged. In this case, since the water flows from the working chamber to the secondary chamber side, the working chamber is in a decompressed state, and therefore the valve body is opened via the working diaphragm, so that the water that has flowed into the primary chamber flows through the valve port into the secondary chamber and is discharged, thereby filling with water.

[0013] In this case, water flows from the working chamber to the secondary chamber, and air in the working chamber is released accordingly. Therefore, air can be released by simply operating the opening and closing valve, which is easy to operate and allows air to be released easily and reliably when filling the tank with water during installation. This also applies to filling the tank with water during maintenance, for example. After filling the tank with water, the above-mentioned reference pressure is set individually for each pressure reducing valve. Then, the opening and closing valve of the bypass pipe is closed. Also, the outflow of water from the fire extinguishing appliance side is stopped, and in the fire extinguishing pressure reducing device, the stop valve of the main base pipe is opened to enable the pressure reducing valve on the main base pipe side, and the stop valve of the bypass base pipe is closed to suspend the pressure reducing valve on the bypass base pipe side, in preparation for an emergency.

[0014] In an emergency such as a fire, water will begin to flow on the fire extinguishing appliance side, so the pressure in the secondary chamber of the pressure reducing valve on the main base pipe side will drop, and when the water pressure in the secondary chamber falls below the reference pressure, the pilot line will function to reduce the pressure in the working chamber and open the valve body via the working diaphragm. As a result, water from the primary chamber will flow through the valve port to the secondary chamber, and water will be supplied to the fire extinguishing appliance. In this case, the opening of the valve body is adjusted by the function of the pilot line, so the pressure on the fire extinguishing appliance side is adjusted and pressure fluctuations are suppressed. In addition, air is reliably bled, so operation can be performed stably and safety can be ensured.

[0015] In this case, the fire extinguishing pressure reducing device can also deal with the situation by opening the stop valve of the bypass main pipe to activate the pressure reducing valve on the bypass main pipe side. In this state, the stop valve of the main main pipe can be closed and the pressure reducing valve on the main main pipe side can be removed and repaired. In other words, even if one pressure reducing valve breaks down, another pressure reducing valve can be used immediately, improving safety.

[0016] If necessary, the conduit may be configured to include a conduit pipe that is piped outside the main body, one end of which is connected to the primary chamber side and the other end of which is connected to the working chamber side, a bag-shaped strainer that has an opening facing the primary chamber, and a holder that is provided on a wall that constitutes the primary chamber of the main body, detachably holds the strainer, and connects one end of the conduit pipe to the opening of the strainer.

[0017] As a result, the strainer faces the primary chamber, and the water in the primary chamber that flows into the working chamber through the conduit enters the strainer and flows from its opening through the conduit to the working chamber. Therefore, foreign matter such as dust is filtered by the strainer, and it is possible to prevent foreign matter such as dust from entering a relatively narrow flow path and causing adverse effects, and safety can be ensured in this respect as well. On the other hand, foreign matter such as dust filtered by the strainer is discharged together with the water that flows from the primary chamber to the secondary chamber, which has a high flow rate, when the valve opening is opened. Therefore, the strainer is not a type that accumulates foreign matter such as dust inside the strainer, but a so-called self-cleaning type, so that it does not become clogged in a short time and maintenance is easy. In addition, since the strainer is detachably held in the holder, when it becomes dirty, it is sufficient to remove the strainer and wash it. Since it can be easily removed and washed, maintenance is also easy in this respect.

[0018] In this case, the strainer is configured to include a strainer body formed into a bag shape using a wire mesh, and a mouthpiece connected to an opening of the strainer body and having a flange formed thereon, It is effective to configure the holder as follows: a holder body attached to the wall portion constituting the primary chamber of the main body, having an insertion hole through which the strainer is inserted, having a receiving surface for receiving the flange of the nozzle of the strainer, and having a male thread formed on its outer periphery; an O-ring fitted onto the flange of the nozzle of the strainer, a ring-shaped nipple for holding the O-ring, and a nut screwed onto the male thread of the holder body and pressing the O-ring via the nipple.

[0019] As a result, the nut presses the O-ring through the nipple, and the gap between the strainer flange and the receiving surface is blocked by the O-ring, providing a good seal and reliably preventing leakage to the outside. Also, the strainer can be attached and detached by operating the nut, improving operability.

[0020] and if necessary, the pilot pipe is configured with a pilot valve provided on the outside of the main body, and the pilot valve is configured to include a pilot main body having one port on the secondary chamber side and another port on the working chamber side to form a flow path through which water flows, a partition provided in the pilot main body to partition the flow path of the pilot main body, an on-off valve for opening and closing a valve opening provided in the partition, a pilot diaphragm provided within the pilot main body and linked to the on-off valve, a pilot spring provided in a chamber related to the operation of the pilot diaphragm, which urges the pilot diaphragm so as to move the on-off valve in an opening direction and is capable of adjusting the urging force, and an adjustment section for adjusting the urging force of the pilot spring, the pilot pipe is arranged outside the main body, one end of the pilot pipe is connected to the other port of the pilot valve and the other end of the pilot pipe is connected to the working chamber side, the other end of the pilot tube and the other end of the conducting tube are connected to the working chamber via a connector provided in the main body; The connector includes a pilot port to which the other end of the pilot tube is connected, a conduit port to which the other end of the conduit tube is connected, a diaphragm port connected to the working chamber, a first passage connecting the conduit port and the pilot port, a first needle valve capable of adjusting a flow rate of the first passage, a second passage connecting the pilot port and the diaphragm port, a second needle valve capable of adjusting a flow rate of the second passage, a third passage connecting the diaphragm port and a communication port provided in the first passage closer to the pilot port than the first needle valve, and a one-way valve provided in the communication port of the third passage and allowing only water to flow from the first passage to the third passage.

[0021] As a result, when the water pressure in the secondary chamber falls below a reference pressure, the pilot conduit reduces the pressure in the working chamber, causing the valve element to open via the working diaphragm. This reference water pressure is set in the pilot valve by adjusting the biasing force of the pilot spring with an adjustment unit. In the function of this pilot conduit, the flow rate of the first passage can be adjusted with the first needle valve and the flow rate of the second passage can be adjusted with the second needle valve in the connecting body, so that water from the working chamber can flow to the secondary chamber together with water from the primary chamber, making the water flow smoother and thus stabilizing the operation of the diaphragm. Effect of the Invention

[0022] As described above, the pressure reducing valve used in the fire extinguishing pressure reducing device of the present invention is installed in the main water supply pipe that supplies water from the water tank due to the difference in height, and pressure fluctuations on the fire extinguishing appliance side can be suppressed, so that it is not necessary to install a valve for each branch water supply pipe as in the past in the fire extinguishing equipment, and a small number of valves can be installed to suppress pressure fluctuations on each fire extinguishing appliance side, thereby improving installation efficiency. In addition, air can be reliably bled when the pressure reducing valve is installed, and safety can be guaranteed when the fire extinguishing appliance is activated. [Brief description of the drawings]

[0023] [Figure 1] 1 is a perspective view showing a pressure reducing valve used in a fire extinguishing pressure reducing device according to an embodiment of the present invention. [Diagram 2] 1 is a diagram showing an example of piping of a pressure reducing valve used in a fire extinguishing pressure reducing device according to an embodiment of the present invention. FIG. [Diagram 3] 1 is an exploded perspective view showing a main part of a pressure reducing valve used in a fire extinguishing pressure reducing device according to an embodiment of the present invention. FIG. [Figure 4] 1 is a plan view showing a pressure reducing valve used in a fire extinguishing pressure reducing device according to an embodiment of the present invention. [Diagram 5] 1 is a cross-sectional view showing a pressure reducing valve used in a fire extinguishing pressure reducing device according to an embodiment of the present invention. [Figure 6] 4 is another cross-sectional view showing a pressure reducing valve used in a fire extinguishing pressure reducing device according to an embodiment of the present invention. FIG. [Figure 7] 2 is an exploded perspective view showing a strainer and its holder provided in a conduit in a pressure reducing valve used in a fire extinguishing pressure reducing apparatus according to an embodiment of the present invention. FIG. [Figure 8] 4 is a cross-sectional view showing a state in which a strainer and its holder are attached to a main body in a pressure reducing valve used in a fire extinguishing pressure reducing apparatus according to an embodiment of the present invention. FIG. [Figure 9] 1 is a diagram showing a schematic configuration of a connector to which a conduit and a bypass pipe are connected in a pressure reducing valve used in a fire extinguishing pressure reducing apparatus according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a pressure reducing valve used in a fire pressure reducing device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. 1 to 6 show a pressure reducing valve V used in a fire extinguishing pressure reducing device S according to an embodiment of the present invention. As shown in FIG. 2, the fire extinguishing pressure reducing device S is installed in a fire extinguishing system F of a high-rise building. In this fire extinguishing system F, fire extinguishing appliances e such as a sprinkler system, a fire water supply pipe connection, an indoor fire hydrant, and an outdoor fire hydrant are installed on required floors. A water tank 1 is installed on an upper floor, and a main water supply pipe 2 is installed to supply water from the water tank 1 due to a difference in height. A plurality of branch water supply pipes 3 are piped to the main water supply pipe 2, and the corresponding fire extinguishing appliances e are connected to each of these branch water supply pipes 3 to enable water to be supplied to them. The fire extinguishing pressure reducing device S is installed in the main water supply pipe 2 of this fire extinguishing system F, upstream of the fire extinguishing appliances e.

[0025] As shown in FIG. 2, the fire extinguishing pressure reducing device S includes a main pipe 4 that is a part of the main water supply pipe 2, and a pressure reducing valve V according to the present embodiment that is interposed in the main pipe 4. The main pipe 4 includes a main pipe 4A and a bypass pipe 4B that is connected in parallel to the main pipe 4A, and the pressure reducing valve V is interposed in the main pipe 4A and the bypass pipe 4B. In addition, a manual stop valve 5 is provided before and after the pressure reducing valve V in the main pipe 4A and the bypass pipe 4B. That is, a main body 10 is connected between a pair of stop valves 5 connected to the main pipe 4A in the middle of the main pipe 4A, and a main body 10 is connected between a pair of stop valves 5 connected to the bypass pipe 4B in the middle of the bypass pipe 4B, so that the pressure reducing valve V is interposed in each of the main pipe 4A and the bypass pipe 4B. Furthermore, a strainer (not shown) can be provided upstream of the pressure reducing valve V in the main pipe 4A and the bypass pipe 4B.

[0026] The pressure reducing valve V according to the embodiment adjusts the water pressure on the fire extinguishing appliance e side, and includes a main body 10 having an inlet 11 and an outlet 12 and forming a flow path through which water flows, as shown in Figs. 1 to 6. The main body 10 includes a pipe 14 in which the inlet 11 and the outlet 12 are formed so that their axes are located on a center line P in one direction. The pipe 14 has an upper opening 15 formed on a center line Q in another direction perpendicular to the center line P in one direction. The upper opening 15 is provided with an upper body 16 that closes the upper opening 15. The main body 10 is composed of the pipe 14 and the upper body 16. The main body 10 is also provided with a partition wall 19 that partitions the flow path to form a primary chamber 17 on the inlet 11 side and a secondary chamber 18 on the outlet 12 side.

[0027] The partition wall 19 is provided with a valve port 20 whose axis is the other-direction center line Q, and a valve body 21 is provided coaxially with the valve port 20 for opening and closing the valve port 20. The valve port 20 is formed in a cylindrical shape, and its opening edge on the secondary chamber 18 side is configured as a valve seat 22. The valve body 21 is configured to include a cylindrical valve body main body 24 that slides on the valve port 20 and has a plurality of notches 23 at equal angular intervals through which water on the primary side can flow out, and a disk 25 that is provided at the bottom of the valve body main body 24 and abuts against the valve seat 22 to prevent water from flowing out from the notches 23.

[0028] The disk 25 of the valve body 21 is fixed to a valve rod 26 that passes through the center of the disk 25 coaxially. One end of the valve rod 26 extends into the primary chamber 17, and the other end extends through the secondary chamber 18 toward the upper opening 15. One end of the valve rod 26 is slidably supported by a guide member 27 that is installed on a wall that constitutes the primary chamber 17. The other end of the valve rod 26 is connected to an operating diaphragm 30 that operates the valve body 21 via the valve rod 26. The main body 10 is provided with a storage chamber 31 that faces the valve port 20 and is separated from the secondary chamber 18 by a partition wall 28 located on the valve port 20 side of the upper opening 15, and in which the operating diaphragm 30 is stored. The storage chamber 31 is composed of an empty chamber 32 that communicates with the secondary chamber 18 on the partition wall 28 side through a narrow passage (not shown), and an operating chamber 33 that is separated by the operating diaphragm 30. The valve rod 26 is provided so as to penetrate a partition wall 28 so as to be movable back and forth, and is slidably supported by a cylindrical guide body 29 provided on the partition wall 28. A diaphragm spring 34 is provided in the actuation chamber 33 for biasing the actuation diaphragm 30 in the direction in which the valve element 21 closes the valve port 20. Reference numeral 30a denotes a diaphragm pressing plate which presses the actuation diaphragm, and 30b denotes a receiving plate for the diaphragm spring 34, and the actuation diaphragm 30 is sandwiched between the diaphragm pressing plate 30a and the receiving plate 30b by a screw means.

[0029] The upper body 16 is provided with an adjustment member 35 that is coaxial with the valve rod 26 and adjusts the stroke of the valve rod 26. The adjustment member 35 has one end on which the other end of the valve rod 26 is slidably supported and has a hole 36 with a bottom against which the other end of the valve rod 26 can strike, and the other end protrudes from the upper body 16. A male thread 37 is formed on the other end of the adjustment member 35, and a female thread 38 is formed on the upper body 16 into which the male thread of the adjustment member 35 is screwed. The male thread 37 of the adjustment member 35 is screwed into the female thread 38, and by moving it forward and backward, the strike position of the other end of the valve rod 26 against the bottom of the hole 36 is changed, making it possible to adjust the stroke. Reference numeral 39 denotes a lock nut screwed onto the male thread 37 of the adjustment member 35.

[0030] The pressure reducing valve V also includes a pilot line 40 that is provided between the secondary chamber 18 and the working chamber 33 and that reduces the pressure in the working chamber 33 when the water pressure in the secondary chamber 18 falls below a reference value, thereby opening the valve body 21 via the working diaphragm 30. The pilot line 40 is configured with a pilot valve 41 provided on the outside of the main body 10. 5, the pilot valve 41 is configured to include a pilot body 44 having one port 42 on the secondary chamber 18 side and the other port 43 on the working chamber 33 side to form a flow path through which water flows, a partition 45 provided in the pilot body 44 to partition the flow path of the pilot body 44, an on-off valve 47 for opening and closing a valve opening 46 provided in the partition 45, a pilot diaphragm 48 provided in the pilot body 44 and linked to the on-off valve 47, a pilot spring 50 provided in an operating chamber 49 related to the operation of the pilot diaphragm 48, which urges the pilot diaphragm 48 so as to move the on-off valve 47 in the opening direction and is capable of adjusting the urging force, and an adjustment portion 51 constituted by a screw means for adjusting the urging force of the pilot spring 50. The pilot conduit 40 is configured to include a pilot pipe 52 that is piped outside the body 10, one end of which is connected to the other port 43 of the pilot valve 41 and the other end of which is connected to the working chamber 33 side.

[0031] A flow passage 53 is formed on the outlet 12 side of the main body 10, through which the pilot valve 41 detects the pressure of the secondary chamber 18, and an adapter 54 is provided on the outside of the main body 10 for connecting one port 42 of the pilot valve 41 to the flow passage 53. In Fig. 4, 55 is a pressure gauge connected to the adapter 54 and measures the pressure on the secondary chamber 18 side. Note that the pressure gauge 55 is omitted in other drawings. Note also that in Fig. 5, the pilot valve 41 is shown in an orientation changed by 90° from the actual orientation shown in Figs. 1 and 4 in order to make it easier to understand the connection relationship with other members.

[0032] Furthermore, the pressure reducing valve V is provided with a conduit 60 which guides the water in the primary chamber 17 to the working chamber 33 and which communicates with the pilot pipe 40. The conduit 60 is provided with a conduit pipe 61 which is piped outside the main body 10 and has one end connected to the primary chamber 17 and the other end connected to the working chamber 33, a bag-shaped strainer 63 which has an opening 62 facing the primary chamber 17, and a holder 70 which is provided in a wall portion constituting the primary chamber 17 of the main body 10, which detachably holds the strainer 63 and which communicates between one end of the conduit pipe 61 and the opening 62 of the strainer 63.

[0033] 7 and 8, the strainer 63 is configured to include a strainer body 64 formed into a bag shape using a wire mesh, and a nozzle 66 connected to an opening 64a of the strainer body 64 and having a flange 65 formed thereon. The holder 70 includes a holder body 71. The holder body 71 is formed to include a male thread 71a that screws into a female thread 13 provided in a wall portion that constitutes the primary chamber 17 of the main body 10, an insertion hole 71b through which the strainer 63 is inserted, a receiving surface 71c that receives the flange 65 of the nozzle 66 of the strainer 63, and a male thread 71d into which a nut 74 described below screws. The holder 70 is also configured to include an O-ring 72 that is fitted over the flange 65 of the mouthpiece 66 of the strainer 63 and abuts against a receiving surface 71c of the holder body 71, a nipple 73 having a female thread 73a for holding the O-ring 72, and a nut 74 that screws into the male thread 71d of the holder body 71 and presses the O-ring 72 via the nipple 73. A connector 75 to which one end of the conducting tube 61 is connected is connected to the female thread 73a of the nipple 73.

[0034] The other end of the pilot pipe 52 and the other end of the conducting pipe 61 are connected to the working chamber 33 via a connector 80 provided in the main body 10 . As shown in FIG. 9 which is a schematic representation of the connecting body 80, the connecting body 80 is configured to include a pilot port 81 to which the other end of the pilot tube 52 is connected, a conduit port 82 to which the other end of the conduit tube 61 is connected, a diaphragm port 83 connected to the working chamber 33, a first passage 84 which connects the conduit port 82 and the pilot port 81, a first needle valve 85 capable of adjusting the flow rate of the first passage 84, a second passage 86 which connects the pilot port 83 and the diaphragm port 81, a second needle valve 87 capable of adjusting the flow rate of the second passage 86, a third passage 88 which connects the diaphragm port 83 and a communication port 88a provided in the first passage 84 on the pilot port 81 side relative to the first needle valve 85, and a one-way valve 89 provided in the communication port 88a of the third passage 88 and which allows only the flow of water from the first passage 84 to the third passage 88. By adjusting the first needle valve 85, the second needle valve 87, and the pilot spring 50 of the pilot valve 41 described later, the force exerted by the operating diaphragm 30 on the operating chamber 33 side relative to the force on the primary chamber 17 side acting on the valve body 21 can be set to an appropriate value. In Fig. 4, reference numeral 90 denotes a pressure gauge that is connected in front of the inlet 82 of the connecting body 80 and measures the pressure on the primary chamber 17 side. Note that the pressure gauge 90 is omitted in the other drawings.

[0035] 1, 2, 4 and 6, the pressure reducing valve V according to the embodiment is provided with a bypass pipe 100 that communicates between the working chamber 33 and the secondary chamber 18. A bypass pipe 101 constituting a part of the bypass pipe 100 and an opening / closing valve 102 consisting of a manual ball valve for opening and closing the bypass pipe 100 are attached to the outside of the main body 10 of the pressure reducing valve V. The opening / closing valve 102 is attached to the upper body 16 of the main body 10 via a connecting pipe 103, and the bypass pipe 101 is piped to the above-mentioned adapter 54 via a connector 104 provided on the opening / closing valve 102. As a result, since the bypass pipe 101 and the opening / closing valve 102 are attached to the outside of the main body 10 of the pressure reducing valve V, for example, in the case where a bypass pipe is provided across the pressure reducing valve V in the main base pipe 4A and the bypass base pipe 4B, installation work is required and becomes complicated, but compared to this, the pressure reducing valve V is compact and the installation efficiency can be improved.

[0036] Here, the setting of the reference pressure by the pilot valve 41 will be described with reference to FIG. (1) With the open / close valve 102 of the bypass pipe 100 closed and the biasing force of the pilot spring 50 not acting, water is allowed to flow into the primary chamber 17. In this state, water in the primary chamber 17 pushes up the valve element 21 of the main body 10 from its underside, and at the same time flows into the operating chamber 33 through the conduit 60 and the connector 80, and also flows into the secondary chamber 18 through the pilot pipe 52 and the pilot valve 41. (2) The water that has passed through the valve element 21 of the main body 10 and the on-off valve 47 of the pilot valve 41 acts on the pilot diaphragm 48 to push up the on-off valve 47 and close it. (3) When the on-off valve 47 is closed, water from the guide passage 60 flows only into the working chamber 33 and presses down the working diaphragm 30 , causing the valve element 21 to close the valve port 20 . (4) In this state, when the biasing force of the pilot spring 50 is increased by the adjusting portion 51, the on-off valve 47 opens. This causes the water in the working chamber 33 to flow through the pilot pipe 52 and the pilot valve 41 to the secondary chamber 18 side, which eliminates the downward force on the working diaphragm 30 and causes the valve body 21 to open the valve port 20. (5) When the valve element 21 opens, part of the fluid that flows through the valve port 20 into the secondary chamber 18 acts on the pilot diaphragm 48 as a closing force for the on-off valve 47. In this state, the biasing force of the pilot spring 50 is adjusted by the adjustment part 51 so as to maintain a balance with the opening force of the on-off valve 47. (6) The pilot valve 41 adjusts the opening of the on-off valve 47 in response to pressure fluctuations in the secondary chamber 18 to set a reference pressure, thereby controlling the pressure in the working chamber 33 of the working diaphragm 30, and as a result, the opening of the valve body 21 is controlled to keep the pressure on the secondary chamber 18 side constant.

[0037] Therefore, when installing the fire extinguishing pressure reducing device S, as shown in FIG. 2, the main pipe 4A and the bypass pipe 4B are piped as part of the main water supply pipe 2, and the pressure reducing valve V and the stop valve 5 are interposed between them. In the pressure reducing valve V, the water tank 1 side is connected to the inlet 11, and the fire extinguishing appliance e side is connected to the outlet 12. Then, so-called water filling is performed. In this case, for example, the stop valve 5 is opened in the main pipe 4A and the bypass pipe 4B, and the fire extinguishing appliance e side is set so that water flows, and water is supplied from the water tank 1 by head, and in this state, the opening and closing valve 102 of the bypass pipe 100 is opened. As a result, water flows into the primary chamber 17 and is guided to the operating chamber 33 through the guide passage 60, and further, the water that flows into the operating chamber 33 flows through the bypass pipe 101 to the secondary chamber 18 and is discharged. In this case, water flows from the working chamber 33 to the secondary chamber 18, so that the working chamber 33 is in a decompressed state, and the valve body 21 is opened via the working diaphragm 30, so that the water that has flowed into the primary chamber 17 flows through the valve port 20 into the secondary chamber 18 and is discharged, and water filling is performed. In addition, in this case, water flows from the working chamber 33 to the secondary chamber 18, so that air in the working chamber 33 is released. Therefore, air can be bled by simply operating the opening and closing valve 102, so that the operability is good and air can be bled easily and reliably when filling water during installation. This is also true, for example, when filling water during maintenance. After filling water, the above-mentioned reference pressure is set and the opening and closing valve 102 of the bypass pipe 100 is closed. In addition, the flow of water from the fire extinguishing appliance e side is stopped, and in the fire extinguishing pressure reducing device S, the stop valve 5 of the main main pipe 4A is opened to activate the pressure reducing valve V on the main main pipe 4A side, and the stop valve 5 of the bypass main pipe 4B is closed to deactivate the pressure reducing valve V on the bypass main pipe 4B side in preparation for an emergency.

[0038] In addition, in an emergency such as a fire, water flows on the fire extinguishing device e side, so that in the pressure reducing valve V on the main base pipe 4A side, the pressure on the secondary chamber 18 side drops, and when the water pressure in the secondary chamber 18 falls below the reference pressure, the pilot pipe 40 functions to reduce the pressure in the working chamber 33 and open the valve body 21 via the working diaphragm 30. Therefore, water on the primary chamber 17 side flows through the valve port 20 to the secondary chamber 18 side, and water is supplied to the fire extinguishing device e. In this case, the opening degree of the valve body 21 is adjusted by the function of the pilot pipe 40, so that the pressure on the fire extinguishing device e side is adjusted and pressure fluctuations are suppressed. In addition, since air is reliably bled, the operation can be performed stably and safety can be ensured.

[0039] In this case, when the water pressure in the secondary chamber 18 falls below the reference pressure, the pilot line 40 reduces the pressure in the working chamber 33, opening the valve body 21 via the working diaphragm 30. The function of this pilot line 40 is to adjust the flow rate of the first passage 84 by the first needle valve 85 in the connecting body 80, and to adjust the flow rate of the second passage 86 by the second needle valve 87. Therefore, water from the working chamber 33 can flow toward the secondary chamber 18 together with water from the primary chamber 17, making the flow of water smoother. This can stabilize the operation of the working diaphragm 30.

[0040] Furthermore, since the strainer 63 facing the primary chamber 17 is detachably held by the holder 70 in the conduit 60, the water in the primary chamber 17 flowing into the working chamber 33 through the conduit 60 enters the strainer 63 and flows from its opening through the conduit 61 to the working chamber 33. Therefore, foreign matter such as dust is filtered by the strainer 63, and it is possible to prevent foreign matter such as dust from entering the relatively narrow flow passages of the needle valves 85, 87 of the connector 80 and causing adverse effects, and safety can be ensured in this respect as well. In addition, since the holder 70 holds the nozzle 66 of the strainer 63 with the O-ring 72, it has good sealing properties and can reliably prevent leakage to the outside.

[0041] On the other hand, foreign matter such as dirt filtered by the strainer 63 is discharged together with the water flowing from the primary chamber 17 to the secondary chamber 18, which has a high flow rate, when the valve port 20 is opened. Therefore, the strainer 63 is not a type that accumulates foreign matter such as dirt inside the strainer 63, but a so-called self-cleaning type, so that it does not become clogged in a short time and maintenance is easy. In addition, since the strainer 63 is detachably held in the holder 70, when it becomes dirty, the strainer 63 can be removed and washed. Since it can be easily removed and washed, maintenance is also easy in this respect. In this case, the strainer 63 can be removed by loosening the nut 74 and removing the conduit 61, so that operability can be improved.

[0042] During the supply of water to the fire extinguishing appliance e, in the unlikely event that the outflow of water from the fire extinguishing appliance e stops, the open / close valve 102 of the bypass pipe 100 is opened. As a result, as described above, water flows from the working chamber 33 to the secondary chamber 18, and the working chamber 33 is put into a reduced pressure state, and therefore the valve body 21 is opened via the working diaphragm 30, so that the water that has flowed into the primary chamber 17 flows through the valve port 20 into the secondary chamber 18, is discharged, and is forcibly supplied to the fire extinguishing appliance e. Therefore, although the function of the pressure reducing valve V is sacrificed, the water supply is secured, and safety can be guaranteed.

[0043] In this case, in the fire extinguishing pressure reducing device S, the stop valve 5 of the bypass main pipe 4B can be opened to activate the pressure reducing valve V on the bypass main pipe 4B side. In this state, the stop valve 5 of the main main pipe 4A can be closed to remove the pressure reducing valve V on the main main pipe 4A side for repair. In other words, in the fire extinguishing pressure reducing device S, even if one pressure reducing valve V breaks down, another pressure reducing valve V can be used, so safety can be reliably improved.

[0044] In this way, the pressure reducing valve V according to the embodiment is installed in the main pipe 4A and the bypass pipe 4B as part of the main water supply pipe 2 that supplies water from the water tank 1 due to the difference in height, and pressure fluctuations on the fire extinguishing appliance e side can be suppressed, so there is no need to install a pressure reducing valve for each branch water supply pipe 3 as in the past, and pressure fluctuations on each fire extinguishing appliance e side can be suppressed with a small number of installations, improving installation efficiency. In addition, air can be reliably bled when the pressure reducing valve V is installed, and the safety of the fire extinguishing appliance e can be guaranteed when it is activated.

[0045] In the above-mentioned fire extinguishing pressure reducing device S, the stop valve 5 of the main main pipe 4A is opened to activate the pressure reducing valve V on the main main pipe 4A side, and the stop valve 5 of the bypass main pipe 4B is closed to deactivate the pressure reducing valve V on the bypass main pipe 4B side, but this is not necessarily limited to this, and the stop valve 5 of the bypass main pipe 4B can also be opened to activate the pressure reducing valve V on the bypass main pipe 4B side at the same time, and appropriate modifications can be made. In addition, in FIG. 2, the case where there is one main water supply pipe 2 is shown, but when there are multiple main water supply pipes 2, a fire extinguishing pressure reducing device S is provided for each main water supply pipe 2. Furthermore, the fire extinguishing pressure reducing device S is not limited to one, and multiple devices may be provided at appropriate positions in the height direction of the main water supply pipe 2. Furthermore, in the fire extinguishing pressure reducing device S, the bypass main pipe 4B is provided in addition to the main main pipe 4A, but this is not necessarily limited to this, and it is of course possible to function without providing the bypass main pipe 4B in particular. Furthermore, in the pressure reducing valve V according to the embodiment, a person skilled in the art can easily make many modifications to these exemplary embodiments without substantially departing from the novel teachings and advantages of the present invention, and many of these modifications are included within the scope of the present invention. [Explanation of symbols]

[0046] F Fire extinguishing equipment e Fire extinguishing equipment S Pressure reducing device for fire extinguishing V Pressure Reducing Valve 1. Aquarium 2 Main water pipe 3 Branch water pipe 4 base tube 4A main base pipe 4B Bypass pipe 5. Stop valve 10 Main unit 11 Inlet 12 Outlet 13 Female thread P One-way center line Q Center line in other direction 14 Body 15 Top opening 16 Upper Body 17 Primary room 18 Secondary room 19 Partition Wall 20. Valve Orifice 21 Valve body 22 Valve seat 23 Notch 24 Valve body 25 Discs 26 Valve stem 27 Guide member 28 Bulkhead 29 Guide body 30 Working diaphragm 31 Storage Room 32 Vacant 33 Working chamber 34 Diaphragm spring 35 Adjustment parts 40 Pilot Pipe 41 Pilot valve 42 One-way 43 Other Exit 44 Pilot body 45 Partition 46 Valve opening 47 On-off valve 48 Pilot diaphragm 49 Vacant Operating Rooms 50 Pilot Spring 51 Adjustment part 52 Pilot tube 53 Distribution path 54 Adapter 55 Pressure Gauge 60 Conduction Path 61 Conduit pipe 62 Aperture 63 Strainer 64 Strainer body 64a opening 65 Flange 66 Cap 70 Holder 71 Holder body 71a Male thread 71b Insertion hole 71c receiving surface 71d Male thread 72 O-ring 73 Nipple 73a Female thread 74 Nut 75 Connector 80 Connectors 81 Pilot Exit 82 Conduction port 83 Diaphragm port 84 1st aisle 85 First needle valve 86 2nd aisle 87 Second needle valve 88 3rd aisle 88a Communication port 89 One-way valve 90 Pressure Gauge 100 Bypass Pipe 101 Bypass pipe 102 Opening and closing valve 103 Connecting Pipe 104 Connector

Claims

1. A pressure reducing valve for a fire extinguishing pressure reducing device provided in a fire extinguishing system in which a plurality of branch water pipes are arranged on a main water supply pipe that supplies water from a water tank due to a difference in height and a fire extinguishing device is provided on each branch water supply pipe, the fire extinguishing pressure reducing device comprising a main water supply pipe that is a part of the main water supply pipe and a pressure reducing valve that is interposed in the main water supply pipe, a main body having an inlet and an outlet and forming a flow path through which water flows; a partition wall provided in the main body and dividing the flow path of the main body to form a primary chamber on the inlet side and a secondary chamber on the outlet side; a valve body for opening and closing a valve port provided in the partition wall; an actuating diaphragm provided in the main body and linked to the valve body for opening and closing the valve body by pressure in a working chamber; a pilot pipe provided between the secondary chamber and the working chamber for reducing the pressure in the working chamber and opening the valve body via the actuating diaphragm when the water pressure in the secondary chamber falls below a reference pressure; and a conduit for directing water from the primary chamber to the working chamber and communicating with the pilot pipe line, a bypass duct connecting the working chamber and the secondary chamber, and a bypass pipe constituting a part of the bypass duct and a manual opening and closing valve for opening and closing the bypass duct are attached to the outside of the main body.

2. 2. A pressure reducing valve for use in a fire extinguishing pressure reducing device as described in claim 1, characterized in that the main pipe of the fire extinguishing pressure reducing device is composed of a main pipe and one or more bypass pipes connected in parallel to the main pipe, and the main body is connected between a pair of stop valves connected to the main pipe midway through, and the main body is connected between a pair of stop valves connected to the bypass pipe midway through, thereby being interposed in each of the main pipe and the bypass pipe.

3. 3. A pressure reducing valve for use in a fire extinguishing pressure reducing device as claimed in claim 1 or 2, characterized in that the conduit is configured to comprise a conduit pipe which is arranged on the outside of the main body, one end of which is connected to the primary chamber side and the other end of which is connected to the working chamber side, a bag-shaped strainer having an opening facing the primary chamber, and a holder which is provided on a wall part constituting the primary chamber of the main body, detachably holds the strainer, and connects one end of the conduit pipe to the opening of the strainer.

4. The strainer is configured to include a strainer body formed into a bag shape using a wire mesh, and a mouthpiece connected to an opening of the strainer body and having a flange formed thereon, 4. A pressure reducing valve for use in a fire extinguishing pressure reducing device as described in claim 3, characterized in that the holder comprises a holder body attached to a wall portion constituting the primary chamber of the main body, having an insertion hole through which the strainer is inserted, having a receiving surface for receiving the flange of the nozzle of the strainer, and having a male thread formed on its outer periphery, an O-ring fitted onto the flange of the nozzle of the strainer, a ring-shaped nipple for holding the O-ring, and a nut screwed onto the male thread of the holder body and pressing the O-ring via the nipple.

5. the pilot pipe is configured with a pilot valve provided on the outside of the main body, the pilot valve being configured with a pilot main body having one port on the secondary chamber side and another port on the working chamber side to form a flow path through which water flows, a partition provided in the pilot main body to partition the flow path of the pilot main body, an on-off valve for opening and closing a valve opening provided in the partition, a pilot diaphragm provided within the pilot main body and linked to the on-off valve, a pilot spring provided in a chamber related to the operation of the pilot diaphragm to urge the pilot diaphragm so as to move the on-off valve in an opening direction and capable of adjusting the urging force, and an adjustment section for adjusting the urging force of the pilot spring, the pilot pipe is arranged outside the main body, one end of the pilot pipe is connected to the other port of the pilot valve and the other end of the pilot pipe is connected to the working chamber side, the other end of the pilot tube and the other end of the conducting tube are connected to the working chamber via a connector provided in the main body; 3. The pressure reducing valve used in a fire extinguishing pressure reducing apparatus according to claim 1, wherein the connecting body comprises: a pilot port to which the other end of the pilot pipe is connected; a conduit port to which the other end of the conduit pipe is connected; a diaphragm port connected to the working chamber; a first passage communicating between the conduit port and the pilot port; a first needle valve capable of adjusting a flow rate of the first passage; a second passage communicating between the pilot port and the diaphragm port; a second needle valve capable of adjusting a flow rate of the second passage; a third passage communicating between the diaphragm port and a communication port provided in the first passage closer to the pilot port than the first needle valve; and a one-way valve provided in the communication port of the third passage for allowing only an inflow of water from the first passage to the third passage.

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