JP2004251423A - Check valve with built-in back pressure valve and piping construction - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a check valve with a built-in back pressure valve, achieving reliable operation with minimized components. <P>SOLUTION: A casing 10 is provided with a primary side passage 11 and a secondary side passage 12, and a check valve element 20 is arranged between these passages. A first spring 24 is provided between the valve element 20 and a first stopper member 23 in the secondary side passage for thrusting the valve element 20 to the primary side passage. On the other hand, a back pressure valve element 30 is built in the check valve element 20, which is closed when pressure in the primary side passage is high and opened when pressure in the secondary side passage is high. The check valve element 20 is opened when liquid is supplied, and the back pressure valve element 30 is opened when pressure in the secondary side passage rises. No need therefore exists for extra piping, which greatly contribute to reduce the size of a filling device. Machining accuracy is improved for the casing of the check valve and easy maintenance and inspection are allowed, and a manufacturing cost is reduced. Furthermore, the stronger and smaller back pressure valve results in the compact check valve. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention uses a check valve having a built-in back pressure valve having a simple and compact structure and a check valve in an LPG filling apparatus for filling a predetermined amount of liquid of a liquefied gas into a preset container. Related to piping structure.
[0002]
[Prior art]
Generally, an LPG filling device that fills a predetermined filling container with a liquid such as a liquefied gas is vaporized by a flow meter or a pipe portion during the filling, and the measurement accuracy is reduced. However, in order to prevent this, a back pressure valve is interposed to prevent this. A predetermined pressure is always applied to the piping up to the back pressure valve to prevent the liquefied gas from evaporating. The piping of a general liquefied gas filling device for this purpose is as shown in FIG. 5, and the liquid from the storage tank 101 is sent under pressure by a supply pump 103 in the piping. The liquid under pressure and pressure is supplied through a gas separator 104, a flow meter 105, and a vapor pressurized back pressure valve 110. In this vapor pressure type back pressure valve, a larger liquid pressure is applied from the primary side passage to the valve body closing the fluid passage with a force obtained by combining the gas pressure of the storage tank 101 and the spring pressure in the back pressure valve. The liquid is supplied by opening the flow path. On the other hand, if the pressure rises in the secondary side passage, the piping is damaged. Opens to release this pressure to the primary side.
[0003]
FIG. 6 shows a simplified LPG filling apparatus whose demand has been increasing in recent years. This is a constitution in which the storage tank 101 is constantly pressurized and supplied in place of the supply pump in the pipe in the above-mentioned constitution. The check valve uses a spring pressurized check valve 110, whereby when the pressurized liquid becomes a predetermined pressure or more, the check valve 110 is opened from the primary side passage to supply the liquid. When the secondary passage rises, the relief valve 140 as a back pressure valve opens to control the pressure in the pipe connected to the secondary passage so as not to exceed a predetermined pressure.
[0004]
On the other hand, in place of the back pressure valve used in these pipes, for example, there is a back pressure valve integrated with a check valve as shown in FIGS. 7 and 8. This is disclosed in Japanese Utility Model Registration No. 2539185, and relates to a structure for preventing an abnormal increase in internal pressure in a hot and cold water mixing faucet. This is because the internal pressure of the secondary passage 112 rises, the cylindrical body including the check valve body 120 resiliently urged by the check valve spring 124 to supply water or hot water from the primary passage 111. The cylindrical body moves toward the primary side passage 111 against the repulsive elasticity of the cylindrical body spring 132 provided outside, and the valve body 130 is separated from the valve seat to open the relief valve. Thus, the high-pressure water in the secondary passage 112 passes through the relief valve and the relief passage in the valve-opened state and is sent to the primary passage 111 to reduce the internal pressure (for example, And Patent Document 1).
[0005]
[Patent Document 1]
Utility Model Registration No. 2539185 (FIGS. 1 and 2)
[0006]
[Problems to be solved by the invention]
As described above, the LPG filling apparatus using the vapor pressurized back pressure valve, the spring pressurized check valve, and the relief valve as the back pressure valve requires one to use the vapor pressure in the storage tank because of its structure, and the other to use the vapor pressure in the storage tank. Since the internal pressure of the secondary passage is prevented from rising more than a certain level via the relief valve, an extra pipe is required for that, and the pipe is complicated. It is desirable to change the back pressure valve in order to simplify the piping. However, when the back pressure valve shown in FIGS. 7 and 8 is used as it is, a high cracking pressure (valve) is used as the back pressure valve. Is required to open the check valve). To achieve this, the load of the check valve spring for pressing the check valve against the valve seat surface of the cylinder is increased, and the check valve spring is It is necessary to keep the load from increasing rapidly and to make the spring constant as small as possible in order to stabilize the flow characteristics. However, with such a conventional back pressure valve integrated with a check valve, the diameter and length of the check valve spring cannot be obtained sufficiently, and in order to obtain a sufficient diameter and length, the entire valve structure must be enlarged. There is a need to do so. In addition, the size of the cylinder is inevitably increased, and as a result, the overall size is increased. Furthermore, if a valve with such a configuration is used as it is, the thickness of the cylindrical body is so thin that it may not be able to withstand the pressure sufficiently. In addition, there are problems such as difficulty in downsizing.
[0007]
A first object of the present invention is to solve such a problem and to obtain a check valve having a simple structure, a minimum number of components, and a built-in back pressure valve that operates reliably. The aim is to obtain a simplified piping structure.
[0008]
[Means for Solving the Problems]
A first object of the present invention is to provide a casing 10 having a primary side passage 11 for supplying a pressurized liquid to one side and a secondary side passage 12 for delivering the liquid to the other side. On the center line connecting the primary side passage 11 and the secondary side passage 12, a check valve body 20 having a valve seat 21 abutting on the peripheral end surface of the primary side passage is disposed, and the check valve body 20 is provided on the other side of the valve body 20. The valve body 20 is pressed against the primary side passage between the first stopper member 23 having a T-shaped cross section, which is attached to the secondary side passage and has a groove 22 through which the liquid passes on the outer periphery. A first spring 24 having a resilient force is provided. On the other hand, a stepped hole formed on the center line of the check valve body 20 is closed when the pressure on the primary passage is high, and is closed on the secondary passage. Back pressure valve element 30 that is opened when the internal pressure of When the liquid is supplied from the primary passage 11, the check valve 20 is opened, and when the pressure on the secondary passage is increased, the back pressure valve 30 is opened. Achieved by providing a stop valve.
[0009]
In addition to this, in addition to the above-described configuration, the casing has a casing body 13 having a through hole 16 formed on the center line thereof, and a casing lid 14 having the primary side passage 11 and being fixedly secured to one end of the casing body 13. And a casing bottom 15 having a secondary side passage 12 and penetratingly fixed to the other end of the casing main body 13, which may be connected to each other by a screw member 18. Is a stepped hole formed in the check valve body 20 and composed of a valve guide hole 27 and a communication hole 26, and is reciprocally movable in the axial direction within the valve guide hole 27 so that one end closes the communication hole 26. A back pressure valve body 30 abutting against the seat surface of the valve guide hole 27, and a second stopper member 31 fixed to the open end of the valve guide hole 27 so as to press the back pressure valve body 30. The back pressure valve 30 is separated from the seat surface when the pressure on the secondary passage side is increased. Therefore, the back pressure valve is reduced in size, and the back pressure valve is compact. A simple check valve is obtained.
[0010]
On the other hand, a second object of the present invention is to supply the liquid supplied from the storage tank 1 which is constantly pressurized to a predetermined pressure to the storage tank 1 in a supply pipe for supplying a predetermined necessary amount. A gas separator 4 for separating air bubbles mixed in the liquid to be separated from the liquid is connected to a pipe, and the liquid separated by the gas separator 4 is passed through a flow meter 5 to a primary side of a check valve having a built-in back pressure valve. It is connected to a passage 11 so that the liquid is delivered from a secondary passage 12 of the check valve, while the gas separated by the gas separator 4 is returned to the storage tank 1 or discharged to the atmosphere. This is achieved by using a piping structure in which piping is connected.
[0011]
In addition, when the pressure in the pipe connected to the secondary side passage 12 of the check valve in the above-described configuration rises to a predetermined pressure or more, the built-in back pressure valve opens to move to the primary side passage 11. Since the pressure in the secondary passage 12 escapes, no extra piping is required, and the entire filling device can be reduced in size.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. In FIG. 1, reference numeral 10 denotes a casing having a primary side passage 11 at one end as an inlet to which a pressurized liquid such as liquefied gas is supplied, and a secondary side passage 12 at the other end as an outlet through which the pressurized liquid is delivered. . This casing comprises a casing body 13, a casing lid 14 penetrated and fixed to both ends thereof, and a casing bottom 15, and the casing body 13 has a through hole 16 having a cylindrical inner surface shape. At both ends of the casing body 13, the entrance side is closed by a casing lid 14, and the exit side is closed by a casing bottom 15. The casing cover 14 and the casing bottom 15 are connected to the second supply pipe 7 serving as the primary passage 11 and the third supply pipe 8 serving as the secondary passage 12, respectively. A sealing member 17 is fitted to a fitting portion between the casing body 15 and the casing bottom 15 so that the inside liquid does not leak, and the casing body 13, the casing lid 14, and the casing bottom 15 are fastened and fixed by screw parts 18. I have.
[0013]
A check valve body 20 having a valve seat 21 that can be brought into close contact with the outer peripheral end face of the primary passage 11 so as to close the primary passage 11 is disposed on a center line in the casing 10. A plurality of grooves 22 are formed in the outer periphery of the check valve body 20 in the axial direction to serve as a liquid passage. The check valve body 20 is elastically urged toward the casing lid by a first spring 24 disposed between the check valve body 20 and a first stopper member 23 located on the bottom side of the casing. It is supported by the bottom 15. A plurality of flow paths 25 are formed at equal intervals on the outer peripheral side of the first stopper member 23. When the check valve body 20 is opened from the primary side passage 11 by a predetermined pressure, the liquid passes therethrough. Then, it is supplied to the secondary side passage 12.
[0014]
Further, a stepped hole is formed on the center line of the check valve body 20, and a thin communication hole 26 constituting the stepped hole is located on the secondary passage side. This communication hole 26 is followed by a larger valve guide hole 27, in which a back pressure valve 30 reciprocating is built. The back pressure valve body 30 is elastically urged by a second spring 32 whose one end is located at a second stopper member 31 fixed to the primary side passage so as to always close the communication hole 26. A plurality of flow paths 33 are formed on the outer peripheral side of the second stopper member 31 at equal intervals.
[0015]
FIG. 2 shows a configuration in which a check valve having a built-in back pressure valve configured as described above is used in a piping structure of an LPG filling device. Next, a description will be given of this piping structure. A first supply pipe 2 is connected to the bottom of the storage tank 1 which is constantly pressurized to a predetermined pressure, and is connected to the storage tank 1 via a supply valve 3. The gas separator 4 is connected. The gas separator 4 separates bubbles mixed in the supplied liquid from the liquid, and is necessary for accurate flow measurement by a flow meter 5 connected to the gas separator 4 by piping. It is. The gas separator 4 is connected to the storage tank 1 via an exhaust pipe 6 and is branched so that the gas can be released into the atmosphere. To be returned to the storage tank 1 or discharged to the atmosphere.
[0016]
On the other hand, the flow meter 5 is connected via a second supply pipe 7 to a primary passage 11 of a check valve incorporating a back pressure valve shown in FIG. Is connected to a third supply pipe 8 for supplying a predetermined amount of liquid to a filling container (not shown). The third supply pipe 8 has a structure in which a liquid supply nozzle (not shown) is connected via an electromagnetic valve 9 that operates to shut off the supply when the filling amount reaches a set amount.
[0017]
In such a configuration, when a start signal is input and the pressurized liquid is supplied from the storage tank 1, this liquid passes through the gas separator 4 from the first supply pipe 2 and passes through the flow meter 5. At this time, the supply amount is measured by the flow meter 5. Subsequently, since the liquid flows while a predetermined pressure is applied, the first spring 24 is bent as shown in FIG. 3, the check valve body 20 is opened, and the liquid flows from the primary side passage 11 to the secondary side. It flows into the side passage 12. In this state, the back pressure valve body 30 is not opened and the communication hole 26 remains closed, so that the liquid flows around the check valve body 20. Thereafter, when a predetermined amount of liquid is supplied and filled in the filling container, a stop signal is input to the solenoid valve 9 and the supply of liquid is shut off. Subsequently, when filling the next filling container with liquid, a start signal is input, and when the solenoid valve 9 is opened, a predetermined amount of liquid is supplied by the same operation.
[0018]
On the other hand, if the pressure in the secondary side passage rises above a predetermined pressure for some reason, this rising pressure acts on the back pressure valve body 30 in the check valve body 20, and as shown in FIG. Since the pressure valve body 30 retreats against the second spring 32, the communication hole 26 is opened. As a result, the pressure escapes from the secondary passage 12 to the primary passage 11, so that the pressure in the secondary passage 12 decreases. Even if the pressure increase in the secondary side passage 12 is repeated in this way, the back pressure valve body 30 is opened each time, so that the pressure in the secondary side passage 12 is reduced each time and the supply pipe is not broken, so that the safety is ensured. Work becomes possible.
[0019]
【The invention's effect】
As is clear from the embodiment described above, the present invention has a casing 10 having a primary side passage 11 for supplying a pressurized liquid to one side, and a secondary side passage 12 for delivering the same to the other side, A check valve body 20 having a valve seat 21 abutting on a peripheral end surface of the primary side passage 11 is disposed between the primary side passage 11 and the secondary side passage 12. A first spring 24 for pressing the valve body 20 toward the primary passage is provided between the attached first stopper member 23 having a T-shaped cross section and a primary side in a stepped hole of the check valve body 20. A back pressure valve body 30 which closes when the pressure on the passage side is high and opens when the internal pressure on the secondary side passage side is high is built in. When the liquid is supplied, the check valve body 20 is opened, and the pressure on the secondary side passage side is increased. When ascending, a back pressure valve configured to open the back pressure valve body 30 is incorporated. A check valve.
[0020]
For this reason, unlike the related art, there is no need to use a vapor pressure or a relief valve, so there is no need to provide extra piping, which can greatly contribute to downsizing of the filling device. In addition, since the casing 10 of the check valve has a configuration in which necessary components are simply fitted into the casing main body 13 and fixed with the screw components 18, the accuracy of the processing is improved and the maintenance and inspection thereof are easy. And the manufacturing cost is also reduced. Further, the back pressure valve is built in the check valve body 20 and has a back pressure valve body 30 reciprocally movable in the axial direction therein and one end of which is resiliently urged so as to close the communication hole 26. When the pressure on the passage side is increased, the back pressure valve body 30 is separated from the seating surface. Therefore, a spring having a load sufficient to operate the check valve and the back pressure valve while obtaining a stable flow rate characteristic is arbitrarily selected and used. In addition to the above, it is possible to sufficiently cope with miniaturization. In addition, the strengths of the check valve and the back pressure valve are improved, and the size of the back pressure valve can be reduced, so that a compact check valve having a built-in back pressure valve can be obtained.
[0021]
Further, in the piping structure using this check valve, a gas separator 4 for separating bubbles mixed in the liquid supplied from the storage tank 1 from the liquid is connected to the storage tank 1 by piping, and the separated liquid is supplied at a flow rate. The check valve is connected to the primary side passage 11 of the check valve via a total 5 so that the liquid is delivered from the secondary side passage 12 of the check valve, while the gas separated by the gas separator 4 is stored in the storage tank 1. Or the atmosphere is released to the atmosphere, so that the piping itself is the minimum necessary, and the entire filling device is reduced in size. Further, each time the pressure in the secondary passage 12 rises above a predetermined pressure, the built-in back pressure valve opens to release the pressure in the secondary passage 12 to the primary passage 11 each time. Accordingly, the pressure in the pipe is always controlled to be equal to or lower than the predetermined pressure, and a specific effect such as a pipe structure capable of obtaining a stable filling operation can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating an embodiment of the present invention.
FIG. 2 is a schematic view showing a pipe according to the present invention.
FIG. 3 is a sectional view showing an open state of a check valve according to the present invention.
FIG. 4 is a sectional view showing an open state of a back pressure valve according to the present invention.
FIG. 5 is a schematic view showing a conventional pipe.
FIG. 6 is a schematic view showing another conventional pipe.
FIG. 7 is a sectional view showing a conventional example of a check valve.
FIG. 8 is a sectional view showing the operation state of FIG. 7;
[Explanation of symbols]
REFERENCE SIGNS LIST 1 storage tank 2 first supply pipe 3 supply valve 4 gas separator 5 flow meter 6 exhaust pipe 7 second supply pipe 8 third supply pipe 9 solenoid valve 10 casing 11 primary side passage 12 secondary side passage 13 casing body 14 casing lid 15 Casing bottom 16 Through hole 17 Sealing material 18 Threaded component 20 Check valve 21 Valve seat 22 Groove 23 First stopper member 24 First spring 25 Flow path 26 Communication hole 27 Valve guide hole 30 Back pressure valve body 31 Second stopper member 32 Second spring 33 Flow path

Claims (5)

One side is provided with a casing (10) having a primary side passage (11) for supplying a pressurized liquid, and the other side is provided with a casing (10) formed with a secondary side passage (12) for delivering the liquid, and the primary side passage in the casing is provided. A check valve (20) having a valve seat (21) on one side abutting on the peripheral end surface of the primary side passage is disposed on a center line connecting the first side passage and the secondary side passage, and the secondary side is provided on the other side of this valve body. The valve body is pressed toward the primary side passage between the first stopper member (23) which is attached to the passage side and has a T-shaped cross section formed with a groove (22) through which the liquid passes on the outer periphery. A first spring (24) having a resilient force is provided. On the other hand, a stepped hole formed on the center line of the check valve body is closed when the pressure on the primary side passage is high and the secondary side passage is closed. Built-in back pressure valve (30) that opens when the internal pressure on the side increases When the next side passage supplying the liquid check valve body is opened, the pressure in the second-side passage side is increased, the check valve incorporating a back pressure valve, wherein the configuration back pressure valve body is opened. The casing has a casing body (13) having a through hole (16) formed on the center line, a casing lid (14) having a primary side passage and penetrating and fixed to one end of the casing body, and a secondary side passage. 2. A back pressure valve according to claim 1, wherein said casing bottom comprises a casing bottom fixed to said other end of said casing body, said casing bottom being connected to each other by a screw member. Check valve. The back pressure valve is formed in a check valve body and has a stepped hole formed by a valve guide hole (27) and a communication hole (26), and is axially reciprocable in the valve guide hole so that one end closes the communication hole. And a second stopper member (31) fixed to the open end of the valve guide hole to press the back pressure valve body so as to press the back pressure valve body. 3. The reverse pressure valve according to claim 1, wherein the back pressure valve body is separated from the seat surface when the pressure on the secondary passage side is increased. Stop valve. In a supply pipe for supplying a predetermined amount of liquid supplied from a storage tank (1) which is constantly pressurized to a predetermined pressure,
A gas separator (4) for separating air bubbles mixed in the liquid to be supplied to the storage tank from the liquid is connected to the storage tank by piping, and the liquid separated by the gas separator has a built-in back pressure valve via a flow meter (5). Connected to the primary passage of the check valve, so that the liquid is delivered from the secondary passage of the check valve, while returning the gas separated by the gas separator to the storage tank or the atmosphere. A pipe structure characterized in that the pipe is connected so as to discharge the pipe. When the pressure in the pipe connected to the secondary passage rises above a predetermined pressure, the built-in back pressure valve opens and the pressure in the secondary passage escapes to the primary passage. The piping structure according to claim 4, wherein:

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