JP6840405B2 - Water flow detector - Google Patents

Description

The present invention closes the sprinkler pipe line from the water source to the sprinkler head so as to divide it into the primary side and the secondary side in normal times, while shifting the primary side to the secondary side due to a pressure drop on the secondary side in the event of a fire. The present invention relates to a water flow detection device provided with a valve body that opens so as to communicate with each other and that sends an operation signal to an alarm when the valve body is opened.

Generally, sprinkler systems installed in buildings and condominiums are equipped with multiple sprinkler pipes that branch off from a single water pipe, and in the event of a fire, only sprinkler pipes whose pressure has been reduced by the operation of the sprinkler head can be used. Water is supplied from the water pipe.

That is, each sprinkler pipe is connected to the water pipe via a water flow detection device so as to function independently.

This water flow detection device includes a valve body that closes the pipeline of the sprinkler pipe so as to divide it into a primary side (supply side) and a secondary side (discharge side) in normal times. When the sprinkler head operates and the pressure on the secondary side of the valve body drops in the event of a fire, the valve body opens the primary side so as to communicate with the secondary side to allow water to flow to the sprinkler head. At this time, an operation signal is sent to the alarm when the valve body is opened.
On the other hand, in normal times, the fire extinguishing fluid in the sprinkler pipe has almost the same pressure on the primary side on the supply side and the secondary side on the discharge side, or the secondary side has a slightly higher pressure than the primary side (primary side). ≤ secondary side), and the valve body is maintained in the closed state in normal times. The pressure on the primary side of the valve body is kept constant in the pressure water tank connected to the water pipe.

By the way, since the secondary side of the valve body of the sprinkler pipe is laid in the attic space partitioned by the ceiling surface, air stays and is easily affected by heat due to the rise in temperature, especially in summer. The internal fire extinguishing fluid may expand due to heat, and the pressure on the secondary side of the valve body may significantly exceed the pressure on the primary side. In that case, if the pressure on the secondary side of the valve body is significantly exceeded, a load is applied to the sprinkler pipe piping equipment and the sprinkler head, and the fire extinguishing fluid may leak.

Therefore, conventionally, a bypass path for bypassing the valve body is provided between the primary side and the secondary side of the valve body of the water flow detection device, and the bypass path of the valve body is as shown in FIG. When the pressure on the secondary side (upper side in FIG. 8) exceeds the pressure on the primary side (lower side in FIG. 8), the secondary side of the bypass path is closed by the pressure difference exceeding the preset pressure difference. It is known that a relief valve 71 is provided to regulate the pressure on the secondary side of the bypass path by converting from the closing position (position shown in FIG. 8) to the valve opening position where the secondary side of the bypass path is opened (the position shown in FIG. 8). See Non-Patent Document 1). The relief valve 71 is urged to the closing position side by the urging force of the urging spring 72, and the pressure difference on the secondary side exceeds the pressure difference between the primary side and the preset by the urging force of the urging spring 72. At that time, only the pressure difference is converted to the valve opening position to adjust the pressure on the secondary side, and when the pressure adjustment is completed, the pressure is converted to the closing position by the urging force of the urging spring 72.

Senju Sprinkler Co., Ltd. (T056180) Wet flow detection device XVIIR type, XVIIR-30S type [Detected flow rate constant 50/60], Fig. 9 of "5.4 Names and functions of each part of relief valve" on page 9 in the instruction manual. (Internet [Search on July 1, 1991] <URL: https://www.senjusp.jp/files/libs/1593/201805240844128510.pdf>)

By the way, the conventional relief valve 71 includes a relief valve body 73 provided in a communication chamber 70 through which the primary side and the secondary side of the bypass path communicate with each other, and the relief valve body 73 is a communication port 74 on the secondary side. The communication port 74 is closed by contacting the peripheral edge from the urging direction of the urging means such as the urging spring 72. In this case, the relief valve body 73 is provided with an annular groove 75 corresponding to the peripheral edge of the communication port 74, and the O-ring 76 housed in the annular groove 75 is provided on the peripheral edge of the communication port 74 by the urging force of the urging means. The communication port 74 is closed by pressure contact.

However, even if the pressure difference between the primary side and the primary side set in advance by the urging force of the urging means exceeds the pressure of the fire extinguishing fluid on the secondary side of the relief valve body 73, the relief valve body 73 is not converted to the valve opening position. The pressure of the fire extinguishing fluid on the secondary side may not be adjusted smoothly.

This is because when the O-ring 76 is pressed against the peripheral edge of the communication port 74 at the closing position of the relief valve body 73, the pressure of the fire extinguishing fluid on the primary side acts on the outer peripheral surface side of the O-ring 76. On the other hand, the pressure of the fire extinguishing fluid on the secondary side acts on the inner peripheral surface side of the O-ring 76. At this time, with respect to the pressure receiving area of the fire extinguishing fluid on the primary side acting on the relief valve body 73 from the primary side of the O-ring 76, the secondary side acting on the relief valve body 73 from the secondary side of the O-ring 76. This is because the pressure receiving area of the fire extinguishing fluid has become smaller, and a large difference in pressure receiving area has occurred between the two. Therefore, even if a large pressure of the fire extinguishing fluid from the secondary side acts on a small pressure receiving area, if there is a large pressure receiving area difference between the primary side and the secondary side, the primary side has a large pressure receiving area. The pressure difference set in advance cannot be easily exceeded by the urging force of the urging means from the side, and it becomes difficult for the relief valve body 73 to convert to the valve opening position.

Moreover, the urging force of the urging spring 72 is set high, for example, 0.35 MPa when the O-ring 76 is pressed against the peripheral edge of the communication port 74 from the expansion / contraction direction of the urging means at the closing position of the relief valve body 73. Has been done. Therefore, the amount of deformation of the O-ring 76 that is in pressure contact with the peripheral edge of the communication port 74 becomes large, the pressure receiving area difference between the primary side and the secondary side becomes larger, and the relief valve body 73 moves to the valve opening position. It becomes even more difficult to convert.

The present invention has been made in view of this point, and an object of the present invention is to allow a difference in pressure receiving area between the primary side and the secondary side of the O-ring on which the fire extinguishing fluid acts on the relief valve body. If the pressure of the fire extinguishing fluid on the secondary side exceeds the preset pressure difference from the primary side, the relief valve body is quickly converted to the valve opening position, so that the fire extinguishing fluid on the secondary side is changed to the primary side. It is an object of the present invention to provide a water flow detection device capable of smoothly performing pressure adjustment by relief.

In order to achieve the above object, in the present invention, the pipeline of the sprinkler pipe is closed so as to be divided into the primary side and the secondary side in normal times, while the primary side is changed to the secondary side due to the pressure drop on the secondary side in the event of a fire. It is assumed that the water flow detection device is provided with a valve body that opens so as to communicate with the valve body, and sends an operation signal to an alarm when the valve body is opened. Further, a bypass path for bypassing the valve body is provided between the conduits between the primary side and the secondary side of the valve body, and the pressure on the secondary side with respect to the pressure on the primary side of the valve body is provided in the bypass path. When the pressure difference exceeds the preset pressure difference, only the pressure difference that exceeds the pressure difference is converted from the closing position that closes the secondary side of the bypass path to the valve opening position that opens the secondary side of the bypass path. A relief valve is provided to relieve the fire extinguishing fluid on the next side to the primary side. The relief valve is slidably supported by the relief valve in a state in which the fire extinguishing fluid can flow to the cylinder-shaped communication chamber through which the primary side and the secondary side of the bypass path communicate with each other, and the secondary side of the sliding surface of the communication chamber is supported. A piston-shaped relief valve body that closes from the primary side to the side, and an urging means that urges the relief valve body from the primary side so as to close to the secondary side of the sliding surface of the communication chamber. An annular groove recessed in the circumferential direction on the outer peripheral surface of the relief valve body and the relief valve body accommodated in the annular groove and secondary to the sliding surface of the communication chamber by the urging force of the urging means. An O-ring that seals the secondary side of the sliding surface in a watertight state when converted to a closing position that closes the side, and an O-ring that is provided on the primary side of the closing position of the relief valve body and is provided on the sliding surface. An enlarged diameter portion is provided so that the O-ring cannot be sealed with respect to the O-ring. Then, at the closing position of the relief valve body, the O-ring is positioned on the secondary side of the sliding surface of the communication chamber, and the communication chamber located on the primary side and the secondary side of the O-ring. The pressure receiving area of the fire extinguishing fluid on the primary side, which has the same sliding surface diameters and acts on the relief valve body from the primary side of the O-ring, and the relief valve body, two more than the O-ring. a pressure receiving area of the extinguishing fluid in the secondary side acting from the next side, characterized in that by one Itasa each other.

As described above, in short, when the relief valve body is closed by the urging force of the urging means from the primary side with respect to the secondary side of the sliding surface of the communication chamber, the closing position for closing the secondary side of the sliding surface of the communication chamber. When converted to, the O-ring housed in the annular groove on the outer peripheral surface of the relief valve body seals the secondary side of the sliding surface in a watertight state, while the pressure of the fire extinguishing fluid on the secondary side is the pressure with the primary side. When the relief valve body is moved to the enlarged diameter portion on the primary side against the urging force of the urging means due to the difference, that is, when it is moved to the enlarged diameter portion of the enlarged diameter portion whose diameter is larger than the outer diameter of the O-ring, it slides. It becomes impossible to seal the O-ring on the surface (diameter expansion part).

At that time, at the closing position of the relief valve body, the O-ring in the annular groove of the piston-shaped relief valve body is in pressure contact with the sliding surface of the cylinder-shaped communication chamber. so that the pressure receiving area of the extinguishing fluid from the secondary side of the pressure receiving area and the O-ring of extinguishing fluid from the primary side to substantially coincide with each other.

Therefore, the pressure of the extinguishing fluid in the primary and secondary sides in the closed position of the relief valve body acts substantially uniformly with respect to O-ring, acting from the primary side and the secondary side of the O-ring against the relief valve element extinguishing The difference in the pressure receiving area of the fluid is as small as possible. As a result, if the pressure difference from the preset primary side exceeds the pressure of the fire extinguishing fluid on the secondary side that has expanded due to heat in summer, the relief valve body is quickly converted to the valve opening position, and the fire extinguishing fluid on the secondary side. Can be relieved to the primary side to smoothly adjust the pressure.

Further, by providing the closing position of the relief valve body on the slope whose diameter decreases as it approaches the secondary side of the sliding surface of the communication chamber from the enlarged diameter portion, the closing position of the relief valve body is the slope of the cylinder-shaped communication chamber. Since the O-ring is in pressure contact with the relief valve body, there is a slight difference between the pressure receiving area of the fire extinguishing fluid from the primary side of the O-ring and the pressure receiving area of the fire extinguishing fluid from the secondary side of the O-ring. , The pressure receiving areas of each other are almost the same.

At this time, since the O-ring is pressed against the slope whose diameter is reduced from the enlarged diameter portion from the primary side to close the secondary side of the sliding surface of the communication chamber, the relief valve body is opened to the primary side. Will move without sliding contact with the sliding surface of the communication room. Therefore, even if there is a slight difference between the pressure receiving area of the fire extinguishing fluid from the primary side of the O-ring with respect to the relief valve body and the pressure receiving area of the fire extinguishing fluid from the secondary side of the O-ring, the fire extinguishing fluid is moved to the primary side of the relief valve body. It becomes easier to open the valve smoothly. As a result, if the pressure difference from the preset primary side exceeds the pressure of the fire extinguishing fluid on the secondary side, the relief valve body is quickly converted to the valve opening position, and the fire extinguishing fluid on the secondary side is relieved to the primary side. The pressure can be adjusted smoothly.

On the other hand, the closing position of the relief valve body is located on the secondary side of the sliding surface of the communication chamber with respect to the enlarged diameter portion, and the sliding of the communication chamber located on the primary side and the secondary side of the O-ring at the closing position. by causing the diameter of the sliding surface matched to each other, so that the pressure receiving area of the extinguishing fluid from the secondary side of the pressure receiving area and the O-ring of extinguishing fluid from the primary side of the O-ring against the relief valve body coincide with each other.

Therefore, fire extinguishing fluid pressure of extinguishing fluid in the primary and secondary sides in the closed position of the relief valve body is uniformly acts against the O-ring, than O-ring against the relief valve body acts from the primary side and the secondary side The difference in pressure receiving area is as small as possible. As a result, if the pressure difference from the preset primary side exceeds the pressure of the fire extinguishing fluid on the secondary side, the relief valve body is quickly converted to the valve opening position, and the fire extinguishing fluid on the secondary side is relieved to the primary side. The pressure adjustment can be performed more smoothly.

It is a block diagram which shows typically the sprinkler system provided with the water flow detection apparatus which concerns on embodiment of this invention. It is a front view of the water flow detection device of FIG. It is a side view of the water flow detection device of FIG. It is a top view of the water flow detection device of FIG. It is a vertical sectional front view which shows the structure of the flow water detection device of FIG. FIG. 5 is a cross-sectional view showing a state in which the relief valve body of the relief valve provided in the bypass path of the water flow detection device of FIG. 2 is converted to a closed position. It is sectional drawing which shows the state which the relief valve body of the relief valve of the water flow detection device which concerns on the modification of embodiment of this invention is converted into the closing position. It is sectional drawing which shows the state which the relief valve body of the relief valve of the water flow detection device which concerns on a prior art is converted into a closing position.

Hereinafter, the present invention will be described in detail based on the illustrated embodiment.

FIG. 1 is a configuration diagram schematically showing a sprinkler system including the water flow detection device according to the embodiment of the present invention, and FIG. 2 is a water flow detection device. This water flow detection device 2 is incorporated and used in a sprinkler system.

First, the sprinkler system in which the water flow detection device 2 of the present invention is used will be briefly described. Generally, in a sprinkler system, a plurality of sprinkler pipes 12, 12 are connected, and in the event of a fire, water is passed only to the sprinkler pipe 12 of the system in which the pressure is reduced by the operation of the sprinkler heads 13, 13, .... Therefore, so that each sprinkler pipe 12 functions independently, the sprinkler is opened on the water supply pipe 11 side by the pressure drop of the pressurized water (fire extinguishing fluid) on the terminal side of the sprinkler pipe 12. At the same time that water is passed through the heads 13, 13, ..., A sprinkler pump 14 and a water flow detection device 2 that sends an operation signal to an alarm device 15 of the system through which water is passed are provided. ing.

2 is a front view of the water flow detection device 2 of FIG. 1, FIG. 3 is a side view of the water flow detection device 2 of FIG. 1, and FIG. 4 is a plan view of the water flow detection device 2 of FIG. Further, FIG. 5 shows a vertical sectional front view showing the configuration of the water flow detection device 2 of FIG.

As shown in FIGS. 2 to 5, the water flow detection device 2 is provided in the valve body housing 20 interposed in the pipeline of the sprinkler pipe 12 connected to the water supply pipe 11 and in the valve body housing 20. It is provided with a valve body 22 that opens and closes the flow passage 21. The valve body 22 rotates the valve body portion 24 which is seated at the time of closing with respect to the valve seat portion 23 provided in the valve body housing 20 and the valve body portion 24 around the shaft 25 supported in the valve body housing 20. It is provided with an arm 26 for opening and closing the flow passage 21. In this case, the valve body housing 20 is interposed between the primary side pipe 121 on the water pipe 11 side of the sprinkler pipe 12 and the secondary side pipe 122 on the sprinkler head 13 side, and is fastened by a plurality of bolts 201 and nuts 202. Has been done.

Further, the sprinkler pipe 12 is filled with pressurized water. In this pressurized water, the primary side pipe 121 (shown by A in FIG. 2) on the water pipe 11 side and the secondary side pipe 122 (shown by B in FIG. 2) on the sprinkler head 13 side have substantially the same pressure or two. The secondary side pipe 122 is set to have a higher pressure (A ≦ B) than the primary side pipe 121. Therefore, the valve body 22 rotatably pivotally attached to the shaft 25 maintains the closed state shown in FIG. 2 in normal times. The pressure of the pressurized water in the primary side pipe 121 is kept constant in the pressure water tank 16 connected to the water pipe 11.

An intermediate chamber communicating with a signal channel (not shown) is opened in the valve seat portion 23 on which the valve body portion 24 is seated. This signal channel communicates with the inside of the three-way pipe 33 via a signal stop valve 32. The three-way pipe 33 is connected to the signal stop valve 32 and is also connected to the drain pipe 10 via the drain portion 34. Further, the three-way pipe 33 is connected to the base end (upstream end) of the pressure switch mounting pipe 36 to which the alarm pressure switch 35 is attached to the tip end (downstream end). A check valve (not shown) for preventing the backflow of water from the drainage portion 34 (drainage pipe 10) is provided on the drainage portion 34 side of the three-way pipe 33.

Further, in the sprinkler system, when it becomes necessary to drain water in the sprinkler pipe 12 due to inspection or replacement of the sprinkler head 13, a control valve 37 provided in the primary side pipe 121 of the sprinkler pipe 12 of the system for performing the work is performed. By closing the pipe and shutting off the water supply from the primary side pipe 121, the valve body 22 of the water flow detection device 2 is prevented from rotating, and in this state, the communication pipe 38 communicating with the secondary side of the sprinkler pipe 12 is provided. By opening the drain valve 39, the water collected in the sprinkler pipe 12 is drained from the drain portion 34 to the drain pipe 10 via the communication pipe 38. In this case, the downstream end of the drainage pipe 10 and the downstream end of the end test valve drainage pipe 28 merge with each other, and the merged water passes through a long confluence pipe 29 extending in the lateral direction to the outdoor side ditch 30. It is discharged to such as.

Here, the function of the water flow detection device 2 will be described.

First, when a fire breaks out, when the sprinkler heads 13, 13, ... Detect the fire and discharge the water, the water pressure of the secondary side pipe 122 is significantly lower than the water pressure of the primary side pipe 121 of the sprinkler pipe 12 (A> B). ), The valve body 22 opens, and the pipeline of the sprinkler pipe 12 is opened. When the pipeline of the sprinkler pipe 12 is opened by the valve body 22, that is, when the valve body 22 is opened, a part of the flowing water flows into the signal channel through the intermediate chamber, and the flowing water is pressured through the three-way pipe 33. It flows into the switch mounting pipe 36 to operate the alarm pressure switch 35. At this time, a part of the water is discharged to the drainage section 34 via the three-way pipe 33, but the drainage of the water to the drainage section 34 is throttled by the orifice (not shown), so that the water pressure in the signal channel is increased. , The pressure required for the operation of the alarm pressure switch 35 is maintained.

Then, when the alarm pressure switch 35 is activated in this way, a fire detection signal is sent to the alarm panel 17, an alarm device 15 such as a motor siren sounds, and a sprinkler pump 14 start signal is sent to the pump control panel 18. The sprinkler pump 14 is operated, and the water from the water source 19 is sent to the sprinkler heads 13, 13, ... Through the water supply pipe 11 and the sprinkler pipe 12, and the watering for fire extinguishing is continued. At this time, in the water flow detection device 2 of another system in which the sprinkler is not operating, the valve body 22 does not rotate because the water pressure of the secondary side pipe 122 is high, and water is sent to the sprinkler pipe 12 of this system. There is no.

Further, a bypass path 27 that bypasses the valve body 22 is provided between the lines of the primary side pipe 121 and the secondary side pipe 122 of the valve body 22 of the sprinkler pipe 12. One end of the bypass path 27 is connected to the secondary side of the valve body 22 of the valve body housing 20, while the other end is connected to the primary side of the valve body 22 of the valve body housing 20. The bypass path 27 is provided with a relief valve 4 that opens the secondary side of the bypass path 27 to the primary side of the bypass path 27 and relieves the pressurized water on the secondary side to the secondary side.

FIG. 6 shows a cross-sectional view showing a state in which the relief valve body of the relief valve 4 provided in the bypass path 27 of the water flow detection device 2 is converted to the closing position. As shown in FIG. 6, the relief valve 4 is provided in the relief valve housing 40 and the relief valve housing 40, and the primary side and the secondary side of the bypass path 27 communicate with each other through the communication ports 41 and 42, respectively. A piston-shaped relief valve that is slidably provided in the communication chamber 43 and the communication chamber 43 and closes the secondary side communication port 42 of the bypass path 27 from the primary side communication port 41 side (primary side of the bypass path 27). A body 44 and a compression spring 45 as an urging means for urging the relief valve body 44 in the closing direction for closing the secondary side communication port 42 of the bypass path 27 are provided.

The relief valve housing 40 has a bottomed cylindrical primary housing portion 47 having a primary side passage 46 to which the primary side of the bypass path 27 is connected by screwing, and the secondary side of the bypass path 27 is connected by screwing. It has a bottomed cylindrical secondary housing portion 49 having a secondary passage 48. One end of the primary side housing portion 47 (the end on the anti-primary side passage 46 side) is expanded in diameter, and the other end of the secondary side housing portion 49 (on the anti-secondary side passage 48 side) is on one end side of the inner peripheral surface of the enlarged diameter portion 471. The end) side is screwed. Further, an O-ring 50 made of nitrile rubber is provided between one end side of the inner peripheral surface of the enlarged diameter portion 471 of the primary side housing portion 47 and the other end side of the outer peripheral surface of the secondary side housing portion 49. An O-ring 50 seals watertightly between one end of the inner peripheral surface of the primary housing portion 47 and the other end of the outer peripheral surface of the secondary housing portion 49.

The communication chamber 43 is formed so as to straddle the inner peripheral surfaces of the primary side housing portion 47 and the secondary side housing portion 49, and the primary side and secondary side passages 46 and 48 are formed through the primary side and secondary side communication ports 41 and 42. It is communicated through. Further, in the communication chamber 43, the sliding surface (inner peripheral surface) on the secondary side housing portion 49 side is formed in a cylinder shape, and the relief valve body 44 is in sliding contact with the sliding surface with a minute gap. ing. On the other hand, the communication chamber 43 includes a diameter-expanded portion 431 that has the largest diameter at the upper end of the inner peripheral surface of the primary housing portion 47. The lower end of the sliding surface of the secondary housing portion 49 of the communication chamber 43 continuous with the diameter-expanded portion 431 is formed on a slope 432 whose diameter decreases toward the secondary passage 48 side.

The relief valve body 44 is provided with an annular groove 441 extending in the circumferential direction at a portion closer to one side in the sliding direction, and an O-ring 51 made of nitrile rubber is provided in the annular groove 441. Then, the relief valve body 44 is subjected to the urging force of the compression spring 45 when the pressure of the secondary side pipe 122 with respect to the pressure of the primary side pipe 121 of the valve body 22 is less than a preset pressure difference (for example, 0.35 MPa). , The O-ring 51 is positioned at the closing position (position shown in FIG. 6) where the O-ring 51 is in contact with the inner peripheral surface of the communication chamber 43 (specifically, the reduced diameter surface on the secondary side passage 48 side) to be watertight. It is sealed. In this case, between the inner peripheral surface of the communication chamber 43 and the outer peripheral surface of the relief valve body 44, there is an outer peripheral surface of the relief valve body 44 that slides with a minute gap with respect to the inner peripheral surface of the communication chamber 43. Although the sealing property is not ensured, it is watertightly sealed by the O-ring 51 that comes into contact with the inner peripheral surface of the communication chamber 43.

The compression spring 45 is contracted between the relief valve body 44 and the bottom of the primary housing portion 47, and urges the relief valve body 44 to be positioned at the closed position. Then, when the pressure of the secondary side pipe 122 with respect to the pressure of the primary side pipe 121 of the valve body 22 exceeds the preset pressure difference, the compression spring 45 is separated from the secondary side of the bypass path 27 by the pressure difference that exceeds the pressure difference. The valve opening position for opening the secondary side passage 48 of the communication chamber 43 from the closing position for closing the secondary side passage 48 of the communication chamber 43 (specifically, the most widened on the inner peripheral surface of the primary side housing portion 47). The relief valve body 44 is automatically converted to the diameter-expanded portion 431), and the O-ring 51 is separated from the sliding surface of the communication chamber 43 so that it cannot be sealed, so that the pressurized water on the secondary side is relieved and adjusted. I try to press it. At this time, the relief valve body 44 is converted to the closing position by the urging force of the compression spring 45 when the pressure adjustment is completed by opening the valve only by the pressure difference.

Further, the bypass path 27 is provided with a first on-off valve 53 that opens and closes the pipeline on the primary side of the relief valve 4. Further, a primary side pressure gauge 55 for detecting the pressure on the primary side of the valve body 22 is connected between the first on-off valve 53 and the relief valve 4 of the bypass path 27 via a branch pipe 56. On the other hand, on the secondary side of the relief valve 4 of the bypass path 27, a secondary side pressure gauge 57 for detecting the pressure on the secondary side of the valve body 22 is connected via a branch pipe 58. Further, the bypass passage 27 is provided with a third on-off valve 59 that opens and closes the pipeline on the secondary side of the branch pipe 58, that is, on the secondary side of the relief valve 4.

Therefore, in the present embodiment, when the relief valve body 44 is closed to the secondary side of the sliding surface of the communication chamber 43 by the urging force of the compression spring 45 from the primary side, the relief valve body 44 is closed to the secondary side of the sliding surface of the communication chamber 43. When the next side is converted to the closing position, the O-ring 51 housed in the annular groove 441 on the outer peripheral surface of the relief valve body 44 seals the secondary side of the sliding surface in a watertight state, while the secondary side is sealed. When the pressure of the pressurized water moves the relief valve body 44 to the diameter-expanded portion 431 on the primary side against the urging force of the compression spring 45 due to the pressure difference from the primary side, the diameter-expanded portion 431 is larger than the outer diameter of the O-ring 51. The diameter of the O-ring 51 becomes large, and it becomes impossible to seal the O-ring 51 with respect to the sliding surface of the communication chamber 43.

In that case, the slope 432 whose diameter is reduced toward the secondary side passage 48 at the lower end of the sliding surface of the secondary side housing portion 49 of the communication chamber 43 in which the closing position of the relief valve body 44 is continuous with the diameter expansion portion 431. Since the O-ring 51 is in pressure contact with the slope 432 of the cylinder-shaped communication chamber 43 at the closing position of the relief valve body 44, from the primary side of the O-ring 51 with respect to the relief valve body 44. Although there is a slight difference between the pressure receiving area of the pressurized water and the pressure receiving area of the pressurized water from the secondary side of the O-ring 51, the pressure receiving areas of the two are substantially the same.

At this time, since the O-ring 51 is pressed against the slope 432 whose diameter is reduced from the enlarged diameter portion 431 from the primary side to close the secondary side of the sliding surface of the communication chamber 43, the relief valve body 44 is on the primary side. When the valve is opened, the communication chamber 43 moves without sliding contact with the sliding surface. Therefore, even if there is a slight difference between the pressure-received area of the pressurized water from the primary side of the O-ring 51 and the pressure-received area of the pressurized water from the secondary side of the O-ring 51 with respect to the relief valve body 44, the primary side of the relief valve body 44. It becomes easier to open the valve to the side smoothly. As a result, if the pressure difference from the preset primary side exceeds the pressure of the pressurized water on the secondary side expanded by heat in summer or the like, the relief valve body 44 is quickly converted to the valve opening position, and the pressurized water on the secondary side is released. It is possible to relieve to the primary side and smoothly adjust the pressure.

The present invention is not limited to the above-described embodiment, and includes various other modifications. For example, in the above-described embodiment, the closing position of the relief valve body 44 is directed toward the secondary side passage 48 side at the lower end of the sliding surface of the secondary side housing portion 49 of the communication chamber 43 continuous with the diameter-expanded portion 431. The diameter of the relief valve body 44 is reduced according to the slope 432, but as shown in FIG. 7, the closing position of the relief valve body 44 increases the urging force of the compression spring, so that the sliding surface of the communication chamber 43 is larger than the slope 432. It is provided at the upper end of the sliding surface of the secondary housing portion 4 which is located on the secondary side and whose diameters of the sliding surfaces of the communication chambers 43 located on the primary side and the secondary side of the O-ring 51 match each other. You may. At this time, a slit (not shown) is provided on the contact surface (upper surface in the drawing) of the relief valve body 44 that comes into contact with the bottom of the secondary housing portion 49, and the relief valve with respect to the bottom of the secondary housing portion 47 is provided. It prevents the decrease of the secondary pressure area due to the adhesion of the body 44.

In this case, the pressure-received area of the pressurized water from the primary side of the O-ring 51 with respect to the relief valve body 44 and the pressure-received area of the pressurized water from the secondary side of the O-ring 51 coincide with each other, and the relief valve body 44 At the closed position, the pressure of the pressurized water on the primary side and the secondary side acts evenly on the O-ring 51, and the pressure receiving area difference of the pressurized water acting on the relief valve body 44 from the primary side and the secondary side of the O-ring 51 is possible. It will be extremely small. As a result, if the pressure difference of the pressurized water on the secondary side exceeds the preset pressure difference from the primary side, the relief valve body 44 is quickly converted to the valve opening position, and the pressurized water on the secondary side is relieved to the primary side for adjustment. The pressure can be applied more smoothly.

Further, in the above embodiment, the pressurized water obtained by pressurizing the water of the water source 19 is used as the fire extinguishing fluid, but the fire extinguishing fluid mixed by adding a chemical after pressurizing the water stored in the water source is used. Needless to say, it is good.

Further, in each of the above-described embodiments, the O-rings 50 and 51 made of nitrile rubber are used, but the O-ring made of rubber such as fluororubber or silicon rubber may be used.

Further, in the above-described embodiment, a part of the pressurized water flowing out when the valve body 22 is opened flows in to operate the alarm pressure switch 35, send a fire detection signal to the alarm panel 17, and sound the alarm device 15. The case where the relief valve 4 is applied to the automatic alarm valve type water flow detection device 2 that sends the start signal of the sprinkler pump 14 to the pump control panel 18 has been described. An operation that sends a fire detection signal to the alarm panel to sound the alarm device based on the open posture of the pivotally attached valve body or the amount of rotation of the shaft, and also sends a sprinkler pump start signal to the pump control panel. By moving the lever, which has a seesaw structure by opening and closing the valve mold and valve body, a fire detection signal is sent to the alarm panel based on the movement of the lever to sound the alarm, and the sprinkler pump to the pump control panel. A relief valve may be applied to an actuated valve type water flow detection device that sends out a start signal. In this case, the opening angle of the valve body due to pressurized water from the primary side of the valve body can be accurately detected. It is possible to accurately send an operation signal to the alarm when the valve body is opened.

12 Sprinkler pipe 121 Primary side piping (primary side pipeline)
122 Secondary side piping (secondary side piping)
15 Alarm 2 Flow detection device 22 Valve body 27 Bypass path 4 Relief valve 41 Primary side communication port 42 Secondary side communication port 43 Communication room 431 Diameter expansion part 432 Slope 44 Relief valve body 441 Relief groove 45 Compression spring (biasing means) )
51 O-ring

Claims (1)

It is equipped with a valve body that closes the sprinkler pipe line so as to divide it into the primary side and the secondary side in normal times, while opening the primary side so as to communicate with the secondary side due to a pressure drop on the secondary side in the event of a fire. In the water flow detection device that sends an operation signal to the alarm when the valve body is opened,
A bypass path for bypassing the valve body is provided between the pipelines on the primary side and the secondary side of the valve body, and the valve body is bypassed.
In the bypass path, when the pressure on the secondary side with respect to the pressure on the primary side of the valve body exceeds a preset pressure difference, a closing position that closes the secondary side of the bypass path by the pressure difference that exceeds the preset pressure difference. A relief valve is provided to relieve the fire extinguishing fluid on the secondary side to the primary side by converting from to the valve opening position to open the secondary side of the bypass path.
The relief valve is
The fire extinguishing fluid is slidably supported in a state where the fire extinguishing fluid can flow to the cylinder-shaped communication chamber through which the primary side and the secondary side of the bypass path communicate, and the primary side with respect to the secondary side of the sliding surface of the communication chamber. A piston-shaped relief valve that closes from
An urging means for urging the relief valve body from the primary side so as to close the sliding surface of the communication chamber with respect to the secondary side.
An annular groove recessed in the circumferential direction on the outer peripheral surface of the relief valve body,
When the relief valve body is housed in the annular groove and is converted into a closing position for closing the secondary side of the sliding surface of the communication chamber by the urging force of the urging means, the secondary side of the sliding surface is changed. With an O-ring that seals the watertight state
An enlarged diameter portion provided on the primary side of the closing position of the relief valve body and expanded so as not to be able to seal the O-ring with respect to the sliding surface.
With
At the closing position of the relief valve body, the O-ring is located on the secondary side of the sliding surface of the communication chamber, and the sliding of the communication chamber located on the primary side and the secondary side of the O-ring. The pressure receiving area of the fire extinguishing fluid on the primary side, which has the same surface diameters and acts on the relief valve body from the primary side of the O-ring, and the secondary side of the relief valve body with respect to the O-ring. the pressure receiving area of the secondary side of the extinguishing fluid acting from water flow detection apparatus characterized by being match each other.

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