JP2004261509A - Pressure control valve for fire extinguishing fluid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure control valve which properly controls a pressure of a fire extinguishing fluid sent to a pump for discharging the fire extinguishing fluid. <P>SOLUTION: The volume of an annular space 18 between an inner periphery of a valve body 11 and an outer periphery of a piston valve 12 changes depending on the movements of the piston valve 12, and a spring 19 in the annular space 18 is elastically deformed. Elastic force to move the piston valve 12 in the direction to increase an area of the flow passage of a fluid passage 17 works because of the spring 19. In the piston valve 12, the area of a second pressure receiving surface 22 which receives the pressure of the fire extinguishing fluid on the side 14 of an outlet for the fluid is larger than that of a first pressure receiving surface 21 which receives the pressure of the fire extinguishing fluid on the side 13 of an inlet for the fluid. An oil accumulating space 50 of an oil tank 51 communicates with the annular space 18, and the oil introduced to the oil accumulating space 50 is filled in the annular space 18. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a pressure control valve for adjusting the pressure of a fire-extinguishing fluid supplied from a fire hydrant or another fire engine to a pump mounted on a fire engine or the like.
[0002]
[Prior art]
If the pressure of the fire extinguishing fluid supplied to the fire extinguishing fluid discharge pump is excessive or suddenly fluctuates, the equipment affected by the pressure may be damaged, or the force acting on a firefighter with a water spray gun may change suddenly. However, there is a risk that water cannot be discharged accurately to the fire extinguishing target.
[0003]
To cope with such a problem, a pressure control valve for a fire extinguishing fluid supplied to a fire extinguishing fluid discharge pump has been proposed (Patent Document 1). The pressure control valve has a fluid body connected to a fire extinguishing fluid supply source and a fluid outlet connected to a fire extinguishing fluid discharge pump, a piston valve reciprocally inserted into the valve body, A fluid passage whose flow area changes according to the movement of the piston valve between the fluid inlet and the fluid outlet, and a volume corresponding to the movement of the piston valve between the inner periphery of the valve body and the outer periphery of the piston valve. An annular space formed so as to change, and a spring arranged in the annular space so as to be elastically deformed in accordance with movement of the piston valve. The piston valve has a first pressure receiving surface that receives the pressure of the fire extinguishing fluid on the fluid inlet side and a second pressure receiving surface that receives the pressure of the fire extinguishing fluid on the fluid outlet side, and the area of the second pressure receiving surface is The area is made larger than the area of the first pressure receiving surface. The spring exerts an elastic force to move the piston valve in the increasing direction of the flow path area. The pressure of the fire extinguishing fluid at the fluid outlet is reduced by the movement of the piston valve in the decreasing direction of the flow path area, and is increased by the movement of the piston valve in the increasing direction of the flow path area. With this, when the pressure of the fire extinguishing fluid supplied from the fire extinguishing fluid supply source is excessive or fluctuates rapidly, the pressure of the fire extinguishing fluid flowing out from the fluid outlet of the valve body can be maintained in an appropriate range. It is planned.
[0004]
[Patent Document 1]
No. 252223 No. [0005]
[Problems to be solved by the invention]
In the above-described conventional pressure control valve, the elastic deformation of the spring accompanying the movement of the piston valve causes friction between the valve body and the piston valve, friction between the spring and the inner periphery of the valve body, and the spring and the piston valve. There is a problem in that it is hindered by friction with the outer periphery, thereby hindering proper control of the pressure of the fire extinguishing fluid. The problem is exacerbated by dirt or rust on the spring, the valve body, and the piston valve.
[0006]
Further, in the above-mentioned conventional pressure control valve, the pressure at the fluid outlet of the fire extinguishing fluid is adjusted by changing the position of the component of the fluid passage inside the valve body. However, since the valve body is incorporated into a fire extinguishing fluid piping system, such a fine adjustment operation is troublesome.
[0007]
An object of the present invention is to provide a pressure control valve for a fire extinguishing fluid that can solve the above problems.
[0008]
[Means for Solving the Problems]
The present invention provides a valve body having a fluid inlet connected to a fire extinguishing fluid supply source and a fluid outlet connected to a fire extinguishing fluid discharge pump; a piston valve reciprocally inserted into the valve body; The movement of the piston valve between a fluid passage whose flow path area changes according to the movement of the piston valve between a fluid inlet and the fluid outlet, and between an inner periphery of the valve body and an outer periphery of the piston valve. An annular space formed so as to change its volume in accordance with the following, and a spring arranged in the annular space so as to be elastically deformed with the movement of the piston valve, wherein the piston valve extinguishes a fire on the fluid inlet side. A first pressure-receiving surface that receives the pressure of the working fluid, and a second pressure-receiving surface that receives the pressure of the fire-extinguishing fluid on the fluid outlet side, and the area of the second pressure-receiving surface is (1) The area of the pressure receiving surface is made larger, and an elastic force is applied by the spring to move the piston valve in the direction in which the flow path area increases, and the pressure of the fire extinguishing fluid at the fluid outlet is reduced by the flow of the piston valve. An oil tank having an oil storage space communicating with the annular space is provided in the pressure control valve, which is reduced by movement in the direction in which the path area decreases and increased by movement in the direction in which the flow area increases. Oil introduced into the space is filled in the annular space.
According to the present invention, the oil filled in the annular space causes friction between the valve body and the piston valve, friction between the spring and the inner periphery of the valve body, and friction between the spring and the outer periphery of the piston valve. And dirt and rust on the spring, the valve body and the piston valve can be prevented. Accordingly, it is possible to prevent the elastic deformation of the spring from being hindered due to the movement of the piston valve, and to appropriately control the pressure of the fire extinguishing fluid.
[0009]
The level of the oil stored in the oil storage space is preferably located above the annular space. Thereby, even if the volume of the annular space fluctuates due to the movement of the piston valve, the annular space can always be reliably filled with oil.
[0010]
The volume of the annular space is reduced by the movement of the piston valve in the decreasing direction of the flow path area, and is increased by the movement of the piston valve in the increasing direction of the flow path area. It is preferable that a second spring is provided so as to be reciprocally movable in accordance with a change in volume, and to provide elasticity for pushing out oil stored in the oil storage space toward the annular space by the piston.
Thus, not only the elasticity of the spring but also the elasticity of the second spring acts on the piston valve, so that the position of the piston valve can be adjusted according to the elasticity of the second spring, and the pressure at the fluid outlet of the fire extinguishing fluid can be adjusted.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
The fire engine 1 shown in FIGS. 1 and 2 includes a fire-extinguishing water discharge pump 4 built in a vehicle body 3 supported by wheels 2. A pipe 5 connected to the suction side of the pump 4 is connected to an open / close cock 6 and a natural water supply port 7 provided on a side surface of the vehicle body 3. The pipe 5 is connected to an on-off cock 6 via a pressure control valve 10 for a fire extinguishing fluid. A hose for conveying pressurized (exceeding atmospheric pressure) fire extinguishing water sent from a fire extinguishing fluid supply source such as a fire engine or a fire hydrant is connected to an intake port 6 a opened and closed by the opening / closing cock 6. One end of a water supply hose 8 for natural water supply held on the side of the fire engine 1 is connected to the natural water supply port 7. The other end of the water supply hose 8 for natural water supply is immersed in fire-fighting water of atmospheric pressure such as a pond or a river. The fire extinguishing water discharged from the pump 4 is sent out to another fire engine, a water discharge gun, or the like via a piping system (not shown). The fire engine may be equipped with a chemical agent tank, mix fire extinguishing water discharged from a pump with the chemical agent, and send out a mixed solution of the chemical agent and water as a fire extinguishing fluid. Further, a mixture of a chemical agent and water as a fire extinguishing fluid may be sucked into the pump 4 via the suction port 6a.
[0012]
As shown in FIG. 3, the pressure control valve 10 includes a cylindrical valve body 11 and a cylindrical piston valve 12 which is coaxially inserted into the valve body 11 and is capable of reciprocating in the axial direction.
[0013]
The valve body 11 has cylindrical first to third members 11a, 11b, and 11c. One end outer periphery of the second member 11b is screwed to an inner periphery of one end of the first member 11a via a seal ring 11d. The outer periphery of the other end of the second member 11b is screwed to the inner periphery of one end of the third member 11c via a seal ring 11e. A screw hole 11g is formed in the first member 11a for screwing a connection bolt between the drain pipe connection port 11f and the suction side opening / closing cock 6, and a screw hole for screwing a connection bolt to the pipe 5 in the third member 11c. 11h is formed. One end of the valve body 11 is a fluid inlet 13 connected to a fire extinguishing fluid supply source, and the other end is a fluid outlet 14 connected to the pump 4. As shown by the arrow in the drawing, the fire extinguishing fluid that has flowed into the valve body 11 from the fluid inlet 13 passes through the inside of the piston valve 12 and flows out of the fluid outlet 14.
[0014]
The piston valve 12 is fitted to the valve body 11 via seal rings 16a and 16b. The piston valve 12 has a flange portion 12a projecting outward in the vicinity of the end on the fluid outlet 14 side.
[0015]
A first pressure receiving surface 21 that receives the pressure of the fire extinguishing fluid at the fluid inlet 13 is formed by the end face of the piston valve 12 on the fluid inlet 13 side. The end face 12 'of the piston valve 12 on the side of the fluid outlet 14 and the end face 12a "of the flange portion 12a on the side of the fluid outlet 14 constitute a second pressure receiving face 22 for receiving the pressure of the fire extinguishing fluid at the fluid outlet 14. The area of the second pressure receiving surface 22 is larger than the area of the first pressure receiving surface 21. In addition, between the inner periphery 11c 'of the third member 11c constituting the valve body 11 and the outer periphery of the piston valve 12. Is provided with a gap, so that the pressure of the fire extinguishing fluid at the fluid outlet 14 acts on the end surface 12a ″ of the flange portion 12a on the fluid outlet 14 side.
[0016]
Between the fluid inlet 13 and the fluid outlet 14, there is formed a fluid passage 17 whose flow passage area changes according to the movement of the piston valve 12. That is, a nut 31 is concentrically fixed to the inner periphery of the valve body 11 via the connection plate 32, and a control member 34 is attached to a screw shaft 33 screwed to the nut 31. The control member 34 has a shape in which large diameter ends of two truncated cones concentric with the valve body 11 are joined to each other, and is arranged at a position facing the first pressure receiving surface 21. The fluid passage 17 is provided between the control member 34 and the first pressure receiving surface 21.
[0017]
The pressure of the fire extinguishing fluid at the fluid outlet 14 is reduced by the movement of the piston valve 12 in the direction toward the fluid inlet 13, whereby the flow passage area of the fluid passage 17 is reduced. It is increased by increasing the road area.
[0018]
An oil-tight annular space 18 is formed between the inner periphery of the valve body 11 and the outer periphery of the piston valve 12. A circumferential groove 11i is formed on the inner circumference of the valve body 11, and the outer circumference of the piston valve 12, the inner circumference of the circumferential groove 11i, the end face 11i 'of the circumferential groove 11i on the fluid inlet 13 side, and the end face of the flange portion 12a on the fluid inlet 13 side. The space surrounded by 12a 'is an annular space 18. Thereby, the volume of the annular space 18 changes according to the movement of the piston valve 12. The volume of the annular space 18 is reduced by the movement of the piston valve 12 in the direction toward the fluid inlet 13, that is, the movement in the direction in which the flow path area decreases, and the movement in the direction toward the fluid outlet 14, that is, It is increased by movement in the increasing direction. Note that the flange portion 12a is in contact with the end surface 11i ″ of the circumferential groove 11i on the fluid inlet 13 side, thereby preventing the piston valve 12 from coming off to the fluid outlet 14 side.
[0019]
A compression coil spring 19 is arranged in the annular space 18. The spring 19 is sandwiched between an end face 11i 'of the circumferential groove 11i on the fluid inlet 13 side and an end face 12a' of the flange portion 12a on the fluid inlet 13 side. Thereby, the spring 19 is elastically deformed with the movement of the piston valve 12. Further, an elastic force is applied by the spring 19 to move the piston valve 12 in the direction in which the flow path area increases.
[0020]
An oil tank 51 having an oil storage space 50 communicating with the annular space 18 is provided. That is, a connection port 11j communicating with the annular space 18 is provided in the valve body 11, and the annular space 18 and the oil storage space 50 are connected via the flexible tube 43 connected to the connection port 11j. The oil introduced into the oil storage space 50 fills the annular space 18.
[0021]
As shown in FIG. 4, the oil tank 51 includes a cylindrical cylinder 52 attached to the fire engine 1 with the axial direction being the vertical direction, an upper cap 53 that covers an upper end opening of the cylinder 52, and a lower end opening of the cylinder 52. And a lower cap 54 that is covered via an oil seal. An air vent hole 53 a is formed in the upper cap 53, and the flexible tube 43 is connected to a connection port 54 a formed in the lower cap 54. A piston 55 is coaxially inserted into the oil tank 51 via an oil seal 56 so that the piston 55 can reciprocate in the axial direction of the cylinder 52. A space surrounded by the piston 55 and the inner surface of the oil tank 51 is an oil-tight oil reservoir. The space 50 is provided. The piston 55 reciprocates as the amount of oil stored in the oil storage space 50 fluctuates according to the volume change of the annular space 18. A second spring 57 is provided for giving elasticity to push oil stored in the oil storage space 50 by the piston 55 toward the annular space 18. The second spring 57 is a compression coil spring, and is elastically deformed by being sandwiched between the piston 55 and the upper cap 53. The level of the oil stored in the oil storage space 50 rises above the annular space 18 so that the annular space 18 is filled with the oil introduced into the oil storage space 50 without the elasticity of the second spring 57. Be located.
[0022]
In the pressure control valve 10, even if the pressure of the fire extinguishing fluid supplied from the fire extinguishing fluid supply source is excessive or rapidly fluctuates, the fire extinguishing that acts on the first pressure receiving surface 21 and the second pressure receiving surface 22. By moving the piston valve 12 so that the pressure of the working fluid and the elasticity of the spring 19 are balanced, the pressure of the fire-extinguishing fluid flowing out of the fluid outlet 14 can be maintained in an appropriate range. For example, when the water discharge amount is up to about 1500 L / min, the fire extinguishing fluid flowing out of the fluid outlet 14 is provided when the pressure of the fire extinguishing fluid supplied from the fire extinguishing fluid supply source is about 0.2 MPa to 1.0 MPa. The pressure of the fluid can be maintained at about 0.05 MPa to 0.35 MPa, and if the amount of water discharged is up to about 2000 L / min, the pressure of the fire extinguishing fluid supplied from the fire extinguishing fluid supply source becomes 0.2 MPa to 1 MPa. When the pressure is about 0.5 MPa, the pressure of the fire extinguishing fluid flowing out from the fluid outlet 14 can be maintained at about 0.05 MPa to 0.55 MPa. By changing the control member 34 by changing the screwing amount of the screw shaft 33 into the nut 31, the flow passage area of the fluid passage 17 can be changed, and the pressure of the fire extinguishing fluid at the fluid outlet 14 can be adjusted. It is possible.
[0023]
According to the pressure control valve 10, the oil filled in the annular space 18 causes friction between the valve body 11 and the piston valve 12, friction between the spring 19 and the inner periphery of the valve body 11, Friction between the outer periphery of the piston valve 12 and the spring 19, the valve body 11, and the piston valve 12 can be prevented from being stained or rusted. Accordingly, it is possible to prevent the elastic deformation of the spring 19 due to the movement of the piston valve 12 from being hindered, and to appropriately control the pressure of the fire extinguishing fluid. Further, since the liquid level of the oil stored in the oil storage space 50 is located above the annular space 18, even if the volume of the annular space 18 fluctuates due to the movement of the piston valve 12, the annular space 18 is always filled with the oil. Can be charged. Further, since not only the elasticity of the spring 19 but also the elasticity of the second spring 57 acts on the piston valve 12, the position of the piston valve 12 is adjusted according to the elasticity of the second spring 57, and the fire extinguishing fluid at the fluid outlet 14 is provided. The pressure can be adjusted. For example, by changing the amount of oil stored in the oil storage space 50, the elasticity of the second spring 57 can be changed, and the pressure of the fire extinguishing fluid at the fluid outlet 14 can be adjusted.
[0024]
The present invention is not limited to the above embodiment. For example, as shown in a first modified example of FIG. 5, the piston 55 and the second spring 57 in the above embodiment are eliminated inside the oil tank 51, the internal pressure of the oil storage space 50 is prevented from fluctuating, and the oil storage space 50 is removed. A known breather 60 with a filter including check valves 60a and 60b and a filter 60c arranged in parallel with each other may be attached to the oil tank 51 in order to prevent dust from entering. Further, in the oil tank 51 of the second modified example of FIG. 6, the piston 55 and the second spring 57 in the above embodiment are eliminated, and one end of the cylindrical screw member 43 'is connected to the nut 61 welded to the oil tank 51. The other end of the cylindrical male screw member 43 ′ is screwed into the connection port 11 j of the valve body 11, and the oil storage space is provided via the nut 61 and the inner peripheral hole of the cylindrical male screw member 43 ′ instead of the flexible tube 43. The annular space 18 is filled with oil introduced from the oil supply port 51c into the oil storage space 50. The oil supply port 51c is screwed with a cap (not shown) with a level gauge. It can be closed by matching.
[0025]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the pressure control valve of this invention, the pressure of the fire extinguishing fluid can be controlled appropriately, and also the adjustment work of the pressure can be performed easily.
[Brief description of the drawings]
FIG. 1 is a side view for explaining the arrangement of a pressure control valve according to an embodiment of the present invention. FIG. 2 is a plan view for explaining the arrangement of a pressure control valve according to an embodiment of the present invention. FIG. FIG. 4 is a partially broken side view of an oil tank of a pressure control valve according to an embodiment of the present invention. FIG. 5 is a partially broken side view of an oil tank of a pressure control valve according to a first modified example of the present invention. FIG. 6 is a partially broken side view of an oil tank of a pressure control valve according to a second modification of the present invention.
4 Fire extinguishing fluid discharge pump 10 Pressure control valve 11 Valve body 12 Piston valve 13 Fluid inlet 14 Fluid outlet 17 Fluid passage 18 Annular space 19 Spring 21 First pressure receiving surface 22 Second pressure receiving surface 50 Oil storage space 51 Oil tank 55 Piston 57 2nd spring

Claims (3)

A valve body having a fluid inlet connected to a fire extinguishing fluid supply source and a fluid outlet connected to a fire extinguishing fluid discharge pump;
A piston valve inserted reciprocally into the valve body,
A fluid passage whose flow area changes according to the movement of the piston valve between the fluid inlet and the fluid outlet,
An annular space formed between the inner periphery of the valve body and the outer periphery of the piston valve so as to change in volume according to the movement of the piston valve;
A spring disposed in the annular space so as to be elastically deformed with the movement of the piston valve,
The piston valve has a first pressure receiving surface that receives the pressure of the fire extinguishing fluid on the fluid inlet side, and a second pressure receiving surface that receives the pressure of the fire extinguishing fluid on the fluid outlet side.
The area of the second pressure receiving surface is made larger than the area of the first pressure receiving surface,
By the spring, an elastic force is applied to direct the piston valve in a direction in which the flow path area increases,
In the pressure control valve, the pressure of the fire extinguishing fluid at the fluid outlet is reduced by movement of the piston valve in a direction in which the flow path area decreases, and increased by movement in a direction in which the flow path area increases.
An oil tank having an oil storage space communicating with the annular space is provided,
A pressure control valve for a fire extinguishing fluid, wherein oil introduced into the oil storage space is filled in the annular space. The pressure control valve for a fire extinguishing fluid according to claim 1, wherein the level of the oil stored in the oil storage space is located above the annular space. The volume of the annular space is reduced by the movement of the piston valve in the decreasing direction of the flow path area, and is increased by the movement of the piston valve in the increasing direction of the flow path area,
A piston is inserted into the oil tank so as to reciprocate according to a change in volume of the annular space,
2. The pressure control valve for a fire extinguishing fluid according to claim 1, further comprising a second spring that provides an elastic force to push oil stored in the oil storage space by the piston toward the annular space. 3.

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