JP5802185B2 - Overflow check valve - Google Patents

Description

  The present invention relates to an overflow check valve capable of preventing gas backflow and preventing gas overflow.

  An example of the conventional overflow check valve is shown in FIG. 6 (see, for example, Patent Document 1). 6 is connected to a low-capacity high-pressure gas tank in a high-pressure gas supply system that supplies fuel gas to a fuel cell from a plurality of high-pressure gas tanks (not shown) having different capacities. It is provided in the fuel supply path 7. The fuel supply path 7 is formed in the housing 5.

  This overflow prevention check valve 1 is formed integrally with a check valve body portion 2a of the check valve 2 and an overflow prevention valve body portion 3a of the overflow prevention valve 3. The valve body 6 formed in this way is slid in the opening and closing direction by one compression spring 4.

  FIG. 6A shows a state in which the valve body 6 of the overflow check check valve 1 is accommodated in an accommodation space formed in the housing 5. A gas inlet port 5a is formed on the right side of the housing space, and the inlet port 5a is connected to a low-capacity high-pressure gas tank. A gas outlet port 5b is formed on the left side of the housing space, and the outlet port 5b is connected to an external connection port.

  FIG. 6A shows a normal valve opening / closing state in which a high-pressure gas having an appropriate flow rate at which the overflow prevention valve 3 does not operate flows in the forward direction from the inlet port 5a and flows out from the outlet port 5b. ing. In this normal state, the check valve body 2a is in the open position with respect to the inlet port 5a, and the overflow preventing valve body 3a is in the open position with respect to the outlet port 5b.

  FIG. 6 (b) shows the open / close state of the valve during overflow when the overflow prevention valve 3 is operating because an excessive flow of high-pressure gas that operates the overflow prevention valve 3 flows in from the inlet port 5a. ing. In this overflow state, the check valve body 2a is in the open position with respect to the inlet port 5a, and the overflow prevention valve body 3a is in the closed position with respect to the outlet port 5b. The valve 3 prevents high-pressure gas from flowing out from the outlet port 5b.

  FIG. 6C shows the open / close state of the valve at the time of reverse flow in which the check valve 2 is operating because high-pressure gas has flowed from the outlet port 5b. In this reverse flow state, the check valve body 2a is in the closed position with respect to the inlet port 5a, and the overflow prevention valve body 3a is in the open position with respect to the outlet port 5b. Is prevented from flowing into the tank from the inlet port 5a.

JP 2012-57788 A

  However, in the conventional overflow check valve 1 shown in FIG. 6, in the normal state shown in FIG. 6A, the valve body 6 is not locked anywhere in the housing 5, and the valve body 6 opens and closes. Since it is in a state that is freely movable in the direction (float state), for example, due to fluctuations in the flow rate of the high-pressure gas that flows in the forward direction, the valve body 6 may behave in an unstable manner, such as reciprocally moving back and forth. . As described above, when the valve body 6 behaves unstablely, the valve body 6 comes into contact with the valve seat formed at the inlet port 5a or the outlet port 5b to generate a contact sound, There arises a problem that frictional heat is generated between the inner surface of the housing 5. Further, the wear of the sliding portion between the valve body 6 and the inner surface of the housing 5 is promoted, and the durability of the overflow check check valve 1 is inferior.

  When the valve body 6 behaves unstablely, pressure fluctuations occur in the vicinity of the valve body 6, and the check valve body portion 2a and the overflow prevention valve body portion 3a may malfunction. Due to the malfunction, the forward flow rate of the high pressure gas may fluctuate or the flow of the high pressure gas may stop.

  In the normal state shown in FIG. 6A, the valve body 6 is not locked anywhere in the housing 5, and the valve body 6 is in a float state in which the valve body 6 moves in the forward and reverse directions. The valve body 6 has a leftward (forward) force in the figure based on the pressure difference between the inlet port 5a and the outlet port 5b, and a rightward (reverse) force in the figure based on the spring force of the compression spring 4. It is because it is the structure hold | maintained in the unstable position which balances.

  The present invention has been made to solve the above-described problems, and improves the durability of the check valve body and the overflow prevention valve body and prevents the occurrence of unstable behavior. An object of the present invention is to provide an overflow check valve that can be simplified and save space.

  An overflow check valve according to the present invention is an overflow check valve including a housing having an inlet and an outlet, and an open position that allows a forward gas flow from the inlet toward the outlet; and the outlet A check valve body movably provided between a closed position for preventing a reverse gas flow from the inlet to the inlet, and the forward movement of the check valve body in the open position. When the pressure difference between the stopper portion provided in the housing and the pressure at the inlet and the pressure at the outlet exceeds a predetermined differential pressure, the forward flow of gas is restricted. An overflow prevention valve element to be blocked, and an urging member that urges the overflow prevention valve element in the reverse direction and urges the check valve element in the reverse direction so as to face the closed position. The check valve body and the overflow prevention valve body are separate bodies. The one in which the features.

  According to the overflow check valve according to the present invention, both the check valve body and the overflow prevention valve body are in the open position, and the gas flows in the forward direction from the inlet to the outlet. In a normal state, the check valve element that moves in the forward direction by the gas flow comes into contact with the stopper portion of the housing, so that the check valve element can be stopped at the open position. The overflow prevention valve element is urged by the urging member and pressed against the check valve element in this normal time. In this way, in the normal state, the check valve body and the overflow prevention valve body are not in a floating state in which they move in the forward direction and the reverse direction. It is possible to prevent the occurrence of unstable behavior such as a violent reciprocation of the valve body and the overflow prevention valve body.

  In the overflow check valve according to the present invention, the overflow prevention valve element has a flange portion for disposing the urging member, and the urging member comprises a single member, The flow preventing valve element may be urged in the reverse direction, and the check valve element may be urged in the reverse direction via the overflow preventing valve element.

  If it does in this way, two independent valve bodies, the valve body for check, and the valve body for overflow prevention can be energized by a single energizing member, respectively. Therefore, the configuration of the overflow check valve can be made compact.

  In the overflow check valve according to the present invention, the pressure receiving area of the check valve element may be larger than the pressure receiving area of the overflow check valve element.

  If it does in this way, it will become easy to make the displacement start flow volume which the valve body for overflow prevention starts closing operation larger than the rated maximum flow volume of an overflow check valve. As a result, it is possible to prevent malfunction of the overflow preventing valve element.

  In the overflow check valve according to the present invention, the check valve body abuts on the stopper portion at a small flow rate smaller than the rated maximum flow rate, and the overflow prevention valve body is excessively larger than the rated maximum flow rate. The pressure receiving area of the check valve body, the pressure receiving area of the overflow preventing valve body, and the spring constant of the urging member are set so as to prevent the forward flow of gas when there are many overflows. Good.

  In this way, as a result of the check valve body abutting against the stopper portion at a small flow rate, the check valve body can be prevented from being floated during normal operation of the overflow check valve, and the sliding portion The durability can be improved, and the generation of sound and heat due to unstable behavior can be prevented. Further, the displacement start flow rate at which the overflow preventing valve element starts the closing operation and the operating flow rate at which the overflow preventing valve element is fully closed can be brought close to each other. As a result, it is possible to narrow the flow range of the gas in which the overflow prevention valve body is in a float state, improving the operating flow accuracy and responsiveness as the overflow prevention valve, and further improving the overflow prevention valve body. Unstable behavior can be prevented.

  According to the overflow check valve according to the present invention, it is possible to prevent unstable behavior such as the reciprocating reciprocating motion of the check valve body and the overflow prevention valve body. Thereby, generation | occurrence | production of the contact sound of each valve body and a housing and generation | occurrence | production of the frictional heat between each valve body and a housing can be prevented or suppressed. Furthermore, the wear of each valve body and the housing can be reduced, and the durability of the overflow check check valve can be improved.

  And since the unstable behavior of the check valve body and the overflow prevention valve body can be prevented, the check valve body and the overflow prevention valve body do not malfunction, and this malfunction occurs. It is possible to prevent the forward flow rate of the gas from fluctuating and the gas flow from stopping.

It is a circuit diagram showing composition of a high-pressure gas filling output system provided with an overflow prevention check valve concerning a 1st embodiment of the present invention. It is a figure for demonstrating the overflow check check valve shown in FIG. 2 is a cross-sectional view showing the check valve of FIG. 1, (a) is a cross-sectional view showing a state where the check valve is open and a check valve is open, and (b) is a check valve. FIG. 4C is a cross-sectional view showing a state in which the check valve is closed and the overflow prevention valve is closed; FIG. It is a figure which shows the relationship between the gas flow rate of the check valve provided in the overflow prevention check valve of FIG. 1 and an overflow prevention valve, and the driving force of each valve. It is sectional drawing which shows the overflow prevention check valve which concerns on 2nd Embodiment of the invention. It is sectional drawing which shows the conventional overflow prevention check valve, (a) is sectional drawing which shows the state in which a check valve is open and an overflow prevention valve is open, (b) is a check valve. Sectional drawing which shows the state of an open state and an overflow prevention valve being closed, (c) is sectional drawing which shows the state of a check valve being closed and an overflow prevention valve being open.

  Hereinafter, an overflow prevention check valve according to first and second embodiments of the present invention, and a high-pressure gas filling output system (hereinafter also simply referred to as “system”) 11 including the same will be described. The overflow check valves 15 and 58 described below and the system 11 including the check valves are only one embodiment of the present invention, and the present invention is not limited to the embodiments and departs from the spirit of the invention. You can add, delete, and change as long as you don't.

  A system 11 including an overflow check valve 15 according to the first embodiment shown in FIG. 1 is provided in a vehicle such as a compressed natural gas vehicle, a hydrogen gas vehicle, and a fuel cell vehicle. A compressed natural gas vehicle and a hydrogen gas vehicle have a gas engine, and a driving force is obtained by burning fuel gas (compressed natural gas (CNG), hydrogen gas, etc.) in the gas engine. Yes. The fuel cell automobile has a fuel cell stack. The fuel cell stack consumes fuel gas to generate electric power, and the generated electric power is supplied to a motor to generate driving force. A fuel gas consumer (not shown) that consumes fuel gas and generates driving force, such as a gas engine or a fuel cell stack, is connected to the high-pressure tank 2 via a system 11. The high-pressure tank 2 can store high-pressure fuel gas of 35 to 70 MPa or more, for example, and the system 11 fills the high-pressure tank 2 with high-pressure gas, The stored fuel gas is output (supplied) to the fuel gas consumer.

  As shown in FIG. 1, the system 11 includes a valve block 16. The valve block 16 includes a filling side check valve 12, an output side filter 13, a solenoid valve 14, and an overflow prevention check. A valve (a check valve with an overflow prevention function) 15 is provided. The valve block 16 is screwed into the opening of the high-pressure tank 2, and the valve block 16 is provided with an external connection port 17. The external connection port 17 can be used as a filling port for filling high-pressure gas and can be used as an output port connected to a fuel gas consumer. An output line 18 that connects the external connection port 17 and the inside of the high-pressure tank 2 is provided inside the valve block 16, and a filling line 19 is provided separately from the output line 18. One end on the downstream side of the filling line 19 is connected to the inside of the high-pressure tank 2, and the other end joins the output line 18. A portion where the filling line 19 joins the output line 18 is a joining portion 20. Thereby, the filling line 19 is connected to the external connection port 17 via the output port side line 18a (a part of the output line 18) that connects the junction 20 and the external connection port 17 to each other.

  The filling line 19 is provided with a filling-side check valve 12. The filling-side check valve 12 allows the flow of high-pressure gas flowing from the junction 20 between the filling line 19 and the output line 18 to the high-pressure tank 2 through the filling line 19, and in the opposite direction, that is, filling from the high-pressure tank 2. The flow of the high-pressure gas flowing through the line 19 to the junction 20 is prevented. Further, the output line 18 is provided with an overflow check valve 15 and an output side filter 13 in this order on the high pressure tank 2 side with respect to the merging portion 20.

  The output side filter 13 has a filter element configured in a sponge shape or a mesh shape, and captures contamination contained in the high-pressure gas. A filling side filter (not shown) equivalent to the output side filter 13 may be provided between the merging portion 20 and the filling side check valve 12 in the filling line 19. This filling-side filter is for capturing contaminants contained in the high-pressure gas flowing from the merging portion 20 through the filling line 19 to the high-pressure tank 2. In the output line 18, an overflow check valve 15 is provided between the output side filter 13 and the merging portion 20.

  The overflow prevention check valve 15 is a check valve with an overflow prevention function shown in FIGS. 2 and 3, and the overflow prevention valve 21 is incorporated in the output side check valve 22. The overflow prevention valve 21 has an overflow prevention valve body 23, and the output side check valve 22 has a check valve body 24.

  Thus, since the overflow check valve 15 has an overflow prevention function and a check valve function, it is compared with the case where the overflow prevention valve 21 and the output side check valve 22 are provided separately. Thus, the overall size of the high-pressure gas filling output system 11 can be reduced.

  The function of the overflow check valve 15 as the output side check valve 22 allows the high-pressure gas flowing out from the high-pressure tank 2 to flow in the output line 18 in the reverse direction, that is, in the high-pressure tank 2. This is a function of preventing the reverse flow of the high pressure gas flowing into the.

  The function of the overflow check valve 15 as the overflow prevention valve 21 is that a pressure difference PS between the pressure P1 of the inlet port 26 on the high pressure tank 2 side and the pressure P2 of the outlet port 27 on the external connection port 17 side (= When P1−P2) becomes equal to or higher than a predetermined set differential pressure PT, it is a function that operates to switch from an open state in which the output line 18 is opened to a closed state in which the output line 18 is closed.

  The electromagnetic valve (open / close valve) 14 shown in FIG. 1 is a normally closed type, for example, and opens and closes by turning on and off a current by a controller (not shown). In the closed state, the solenoid valve 14 permits the flow of high-pressure gas flowing from the external connection port 17 in the output port side line 18a formed between the external connection port 17 of the output line 18 and the merging portion 20. In the opposite direction, that is, the state of blocking the flow of the high-pressure gas flowing out from the high-pressure tank 2 side, the function of the check valve is achieved. When the electromagnetic valve 14 is open, the output port side line 18a is released.

  Next, the operation of the system 11 configured as described above will be described. When the system 11 is used to output the high-pressure gas in the high-pressure tank 2, for example, an operator operates a controller, and an electric current is applied to the electromagnetic valve 14 by the controller. As a result, the electromagnetic valve 14 is opened and the output line 18 is opened. When the output line 18 is opened, the high-pressure gas stored in the high-pressure tank 2 is guided to the external connection port 17 through the output-side filter 13, the overflow check check valve 15, and the electromagnetic valve 14, and further to the external connection port 17. It is output to the fuel consumer via the connection port 17. The output high-pressure gas is consumed by the fuel consumer. Thus, by passing the high-pressure gas through the output-side filter 13, the contamination contained in the high-pressure gas can be captured by the output-side filter 13, and the contamination can be prevented from reaching the fuel consumer. In addition, since the filling side check valve 12 is provided in the filling line 19, high pressure gas is not output from the filling line 19.

  Next, when filling the high-pressure gas into the high-pressure tank 2, the electromagnetic valve 14 is kept closed and the high-pressure gas is supplied to the external connection port 17. The high-pressure gas supplied to the external connection port 17 is guided to the output line 18 and the filling line 19. The high pressure gas guided to the filling line 19 opens the filling side check valve 12 to open the filling line 19 and flows into the high pressure tank 2. Thereby, the high-pressure tank 2 is filled with the high-pressure gas.

  Further, the high-pressure gas guided to the output line 18 is guided to the outlet port 27 of the overflow check check valve 15, and the check valve body 24 is placed on the check valve seat 29 (see FIG. 3C). As a result, the overflow check valve 15 can close the output line 18. Therefore, in the output line 18, the flow of the high-pressure gas that is going to flow back into the high-pressure tank 2 is stopped by the overflow check valve 15, so that the high-pressure gas flows back through the output line 18 and causes the output side filter 13 to flow. It can be prevented from passing. Thereby, it is possible to prevent the contamination captured by the filter when the high pressure gas is output from returning to the high pressure tank 2 side when the high pressure gas is filled.

  In this way, contamination captured by the filter at the time of high-pressure gas output can be prevented from detaching from the filter when filling with high-pressure gas, so that damage to the filter element due to separation of this contamination can be prevented, Generation of new contamination due to damage to the filter element can be prevented.

  Next, the overflow check valve 15 according to the present invention will be described in detail. As shown in FIG. 3A, this overflow prevention check valve 15 includes a housing 28, an overflow prevention valve body 23, an overflow prevention valve seat 25, a check valve body 24, A stop valve seat 29 and a spring member (biasing member) 30 are provided.

  A housing 28 of the overflow check check valve 15 shown in FIG. 3A is a part of the valve block 16, and an inlet port 26 and an outlet port 27 are formed. The inlet port 26 is connected to the inside of the high-pressure tank 2, and the outlet port 27 is connected to the external connection port 17 via the junction 20 and the electromagnetic valve 14. Further, a valve body hole 31 extending along a predetermined axis is formed in the housing 28, and an inlet port 26 and an outlet port 27 are formed at both ends of the valve body hole 31, respectively.

  The valve body hole 31 is formed in a substantially circular cross section, and the valve body hole 31 has a large diameter hole 31a on the inlet port 26 side and a small diameter hole 31b on the outlet port 27 side. A medium diameter hole 31c is formed between the large diameter hole 31a and the small diameter hole 31b. A check valve seat 29 is formed on the inner surface of the housing 28 between the large diameter hole 31a and the inlet port 26, and a check valve body 24 is mounted in the large diameter hole 31a. The gap formed by separating the check valve body 24 from the check valve seat 29 functions as a throttle according to the output flow rate, and this portion is formed as a check valve throttle portion 53. Yes.

  An overflow preventing valve body 23 is mounted in the medium diameter hole 31c and the small diameter hole 31b. Further, the overflow prevention valve seat 25 is formed on the inner surface of the housing 28 between the small diameter hole 31b and the outlet port 27, and the end of the overflow prevention valve body 23 is disposed in the small diameter hole 31b. And the clearance gap formed between the outer diameter of the valve body 23 for overflow and the small diameter hole 31b functions as a throttle according to an output flow rate, and this part is formed as the throttle part 54 for an overflow prevention valve. ing.

  As shown in each drawing of FIG. 3, the check valve body 24 is attached to the large-diameter hole 31a so as to be movable forward and backward along the axial direction of the large-diameter hole 31a. Further, as shown in FIG. 3 (a), the check valve body 24 has a circular cross-sectional shape, an upstream tip portion formed in a conical shape, an intermediate portion formed in a columnar shape, and The downstream side portion is formed as a flange portion 24a having a larger diameter than the intermediate portion. As shown in FIG. 3A, the collar portion 24a is for restricting the forward movement of the check valve body 24 at a predetermined open position.

  As described above, the forward movement of the check valve body 24 is restricted at the predetermined open position because the stopper portion formed on the inner surface of the housing 28 between the large diameter hole 31a and the medium diameter hole 31c. This is because the collar portion 24 a contacts the (stepped portion) 55. The forward direction is a direction from the inlet port 26 toward the outlet port 27.

  The check valve body 24 is formed with a first communication hole 56. The first communication hole 56 is, for example, one or more radial holes 56a, and an axial direction communicating with the radial holes 56a. And a hole 56b.

  The radial hole 56 a is formed so as to extend in the radial direction of the check valve body 24, and is opened on a side surface of the check valve body 24. The axial hole 56 b is formed so as to extend in the axial direction of the check valve body 24, and opens at the end face on the downstream side of the check valve body 24.

  As shown in each drawing of FIG. 3, the overflow prevention valve body 23 is mounted on the medium diameter hole 31c and the small diameter hole 31b so as to be movable back and forth along the axial direction of the medium diameter hole 31c and the small diameter hole 31b. Yes. 3A has a circular cross-sectional shape, an upstream tip is formed as a large diameter portion, and an intermediate portion is formed as a cylindrical small diameter portion. And the downstream side is formed in a conical shape.

  The overflow prevention valve body 23 is formed with a second communication hole 32. The second communication hole 32 is, for example, one or more radial holes 32a and a shaft communicating with the radial hole 32a. Direction hole 32b.

  The radial hole 32a is formed so as to extend in the radial direction of the overflow preventing valve body 23, and is opened on the side surface of the small diameter portion of the overflow preventing valve body 23. The axial hole 32 b is formed so as to extend in the axial direction of the overflow preventing valve element 23, and opens at the upstream end face of the overflow preventing valve element 23. And as shown in FIG. 3, the 1st communicating hole 56 and the 2nd communicating hole 32 are formed in the position which mutually communicates.

  As shown in FIG. 3A, a spring member 30 is mounted on the outer side of the small diameter portion on the downstream side of the overflow preventing valve body 23. The spring member 30 is, for example, a compression coil spring, and urges the overflow preventing valve body 23 with a spring force in a direction toward the inlet port 26. One end of the spring member 30 is in contact with the large diameter portion of the overflow preventing valve body 23, and the other end is in contact with a step portion 34 formed on the outlet port 27 side of the housing 28.

  Next, with reference to FIGS. 3A, 3B, and 3C, the operation of the overflow check valve 15 will be described. FIG. 3A shows a state in which the electromagnetic valve 14 is open and the high-pressure gas in the high-pressure tank 2 is output from the external connection port 17. In this output state, the check valve body 24 is in a valve open state away from the check valve seat 29. The overflow prevention valve element 23 is in an open state away from the overflow prevention valve seat 25.

  In the normal state (output state) shown in FIG. 3A, the force relationship between the spring force F2 of the spring member 30 and the force F1 in the W1 direction based on the differential pressure between the inlet port pressure P1 and the output port P2 is obtained. The check valve body 24 is separated from the check valve seat 29.

  In this normal state, the high-pressure gas flowing in from the inlet port 26 passes through the first communication hole 56, the second communication hole 32, the outlet port 27, and the electromagnetic valve 14, as indicated by the arrow 35, and the external connection port. 17 is output.

  The gap (check valve throttle portion 53) formed by separating the check valve body 24 from the check valve seat 29 functions as a throttle according to the output flow rate. Accordingly, a pressure loss ΔP1 occurs in the check valve restricting portion 53, and the check valve body 24 receives a driving force in the W1 direction due to the pressure loss.

  Further, as shown in FIG. 3A, in the normal time when the high pressure gas flows in the forward direction W1 flowing in from the inlet port 26 and flowing out from the outlet port 27, the check valve body 24 Although it moves in the forward direction by the flow, the check valve body 24 can be stopped in the open position by the collar portion 24a coming into contact with the stopper portion 55 of the housing 28. The overflow prevention valve element 23 is urged by the spring member 30 and pressed against the downstream end face of the check valve element 24 in this normal state. Thus, in the normal state, the check valve body 24 is in contact with the housing 28, and the valve bodies 24 and 23 are not in a float state in which they can move in the forward and reverse directions. For example, the unstable behavior of the check valve body 24 and the overflow prevention valve body 23 due to the flow rate fluctuation of the high-pressure gas can be prevented.

  Therefore, according to this overflow prevention check valve 15, the unstable behavior of the check valve body 24 and the overflow prevention valve body 23 can be prevented. Generation of contact noise when contacting the valve seat 29 and the overflow prevention valve seat 25 and generation of frictional heat between the valve bodies 24 and 23 and the inner surface of the housing 28 can be prevented or suppressed. Further, the wear of the sliding portion between the check valve body 24 and the overflow prevention valve body 23 and the inner surface of the housing 28 is reduced, and the durability of the overflow check check valve 15 is improved. be able to.

  In addition, since the unstable behavior of the check valve body 24 and the overflow prevention valve body 23 can be prevented, the check valve body 24 and the overflow prevention valve body 23 do not malfunction, and this malfunction does not occur. It can be prevented that the flow rate of the high-pressure gas in the forward direction W1 fluctuates and the flow of the high-pressure gas stops.

  Further, as shown in FIG. 3A, the spring member 30 urges the overflow preventing valve body 23 and presses it against the check valve body 24, and moves the check valve body 24 toward the closed position. By adopting such a configuration, the spring member 30 can be used as a common part used for the overflow preventing valve body 23 and the check valve body 24. Thereby, the number of parts and the cost of the overflow check valve 15 can be reduced, and the overflow check valve 15 can be simplified and saved in space.

  Furthermore, the first communication hole 56 is provided in the check valve body 24, and the second communication hole 32 is provided in the overflow prevention valve body 23, so that the gas flow path is compared with that provided outside the valve body. Thus, the overflow check check valve 15 can be downsized.

  And according to the overflow prevention check valve 15 shown to Fig.3 (a), the overflow prevention valve 21 is integrated in the output side check valve 22, and the overflow prevention valve 21 has for overflow prevention. Since the valve body 23 and the check valve body 24 of the output side check valve 22 are arranged so as to be in back contact with each other, they can be accommodated in an integral space. The entire gas filling output system 11 can be reduced in size. Further, since the large-diameter hole 31a can serve as a passage between the overflow prevention valve body 23 and the check valve body 24, the length of the passage can be shortened. Thereby, the pressure loss of the output line 18 can be reduced.

  In addition, since the overflow preventing valve body 23 and the check valve body 24 are arranged in back contact with each other, the responsiveness of the overflow preventing valve body 23 to the outflow rate can be improved. Thereby, the outflow amount of the high-pressure gas until the overflow prevention valve 21 is closed can be reduced.

  FIG. 3B shows a state in which, for example, the downstream portion of the output line 18 from the overflow check valve 15 is mechanically damaged, and the high pressure gas in the high pressure tank 2 flows out from the damaged portion. This shows a state at the time of overflow in which the flow rate of the high-pressure gas flowing from the inlet port 26 in the overflow check valve 15 is equal to or higher than a predetermined set flow rate. In this overflow state, the differential pressure PS is equal to or higher than a preset differential pressure PT, and the W1 direction based on the differential pressure PS (the valve closing direction in which the overflow prevention valve body 23 faces the overflow prevention valve seat 25). This force F1 overcomes the force F2 in the W2 direction (the valve opening direction in which the overflow prevention valve element 23 is separated from the overflow prevention valve seat 25) by the spring member 30 or the like.

  That is, the gap (overflow prevention valve restrictor 54) formed between the outer diameter of the overflow prevention valve body 23 and the small diameter hole 31b functions as a restriction that generates a pressure loss corresponding to the flow rate. . Accordingly, a pressure loss ΔP2 occurs in the restrictor 54 for the overflow prevention valve. Due to the pressure loss ΔP2, the overflow preventing valve body 23 receives a driving force in the W1 direction.

  As a result, the overflow prevention valve element 23 is displaced in the W1 direction and is seated on the overflow prevention valve seat 25, whereby the outlet port 27 can be closed. As a result, the high-pressure gas in the high-pressure tank 2 can be reliably stopped in a short time from flowing out through the output line 18, and the amount of gas flowing out to the outside can be reduced. Therefore, loss due to the outflow of the high-pressure gas in the high-pressure tank 2 can be reduced, and when the outflow of the high-pressure gas affects the surrounding environment, the influence on the surrounding environment can be prevented.

  FIG. 3C shows a state (filled state) during reverse flow in which the electromagnetic valve 14 is closed and the high-pressure gas is filled from the external connection port 17. In this reverse flow state, the check valve body 24 is in a closed state in contact with the check valve seat 29. The overflow prevention valve element 23 is in an open state in which the outlet port 27 is opened away from the overflow prevention valve seat 25. That is, in this backflow state, the outlet port pressure P2 is larger than the inlet port pressure P1, and the total force F2 of the force based on the differential pressure PS (= P2−P1) and the spring force of the spring member 30 The overflow prevention valve body 23 and the check valve body 24 are urged toward the check valve seat 29 (W2 direction), and the check valve body 24 is pressed against the check valve seat 29. As a result, the filling gas flowing into the outlet port 27 side is blocked from flowing into the inlet port 26 side.

  Further, as shown in FIG. 3B, the overflow prevention valve element 23 is seated on the overflow prevention valve seat 25, thereby forming an outlet port 27 (first valve) formed in the overflow prevention valve seat 25. Hole) can be closed. As shown in FIG. 3C, the check valve body 24 is seated on the check valve seat 29, thereby opening the inlet port 26 (second valve hole) formed in the check valve seat 29. Can be closed. Thereby, the outlet port 27 formed in the overflow prevention valve seat 25 and the outlet port 27 formed in the check valve seat 29 can be closed with high airtightness.

  As shown in FIG. 4, the driving force of the check valve body 24 is the product of the pressure loss ΔP1 at the check valve restricting portion 53 and the pressure receiving area A1 of the check valve body 24. The driving force of the valve body 23 is the product of the pressure loss ΔP2 at the overflow prevention valve restricting portion 54 and the pressure receiving area A2 of the overflow prevention valve body 23. Therefore, when the pressure receiving area of the check valve body 24 is larger than the pressure receiving area of the overflow preventing valve body 23, the displacement start flow rate at which the overflow preventing valve body 23 starts the closing operation is set as the overflow preventing check valve. It becomes easy to make it larger than the rated maximum flow rate of 58. As a result, malfunction of the overflow preventing valve body 23 can be prevented.

  Further, the check valve body 24 abuts against the stopper portion 55 when the flow rate is smaller than the rated maximum flow rate Qmax of the overflow check valve 58, and the overflow check valve body 23 is connected to the overflow check check valve 58. The pressure receiving area of the check valve body 24, the flow path area of the check valve restricting portion 53, and an overflow prevention so as to prevent the forward flow of the gas in the case of excessive flow that is excessively larger than the rated maximum flow rate Qmax. The following effects are obtained by setting the pressure receiving area of the valve body 23, the flow path area of the restrictor 54 for the overflow prevention valve, the spring constant of the spring member 30, and the urging force.

  That is, as a result of the check valve body 24 coming into contact with the stopper portion 55 at a small flow rate, the check valve body 24 can be prevented from being floated during normal operation of the overflow check valve 23, and the durability can be improved. Improvement can be achieved, and generation of sound and heat due to unstable behavior can be prevented. Furthermore, the displacement start flow rate Qexf1 at which the overflow preventing valve body 23 starts the closing operation and the operating flow rate Qexf2 at which the overflow preventing valve body 23 is fully closed can be brought close to each other. As a result, the flow range of the gas in which the overflow preventing valve body 23 is in a float state can be narrowed, the operating flow rate accuracy and responsiveness as the overflow preventing valve are improved, and the overflow preventing valve body is further improved. 23 unstable behavior can be prevented.

  Next, an overflow prevention check valve 58 according to a second embodiment of the present invention will be described with reference to FIG. The difference between the overflow check valve 58 according to the second embodiment shown in FIG. 5 and the overflow check valve 15 of the first embodiment shown in FIG. 3 is different from the first embodiment shown in FIG. In the embodiment, the overflow prevention valve seat 25 is formed on the inner surface of the housing 28 between the small diameter hole 31b and the outlet port 27, whereas in the second embodiment shown in FIG. 5, the small diameter hole 31b is omitted. The overflow prevention valve seat 25 is formed on the inner surface of the housing 28 between the medium diameter hole 31 c and the outlet port 27.

  Even if it does in this way, the same function as 1st embodiment is made by making the clearance gap formed when the valve body 23 for overflow prevention separates from the overflow prevention valve seat 25 into the throttle part 54 for overflow prevention valves. Fulfill. Further, the second communication hole 32 of the overflow prevention valve body 23 may be used as the overflow prevention valve restricting portion 54.

  Except for this, the configuration is the same as that of the first embodiment and acts in the same way, so the equivalent parts are denoted by the same reference numerals and the description thereof is omitted.

  However, in each of the embodiments described above, for example, as shown in FIG. 3, the outlet port 27 is opened and closed by attaching and detaching the overflow prevention valve body 23 to the overflow prevention valve seat 25. Instead, when the overflow preventing valve body is displaced in the W1 direction as shown in FIG. 3B, the opening of the radial hole 32a of the second communication hole 32 is blocked by the inner surface of the housing 28, for example. When the overflow prevention valve element is displaced in the W2 direction as shown in FIGS. 3A and 3C, the opening of the radial hole 32a of the second communication hole 32 is, for example, A configuration may be adopted in which the outlet port 27 is opened and closed by switching from the inner surface of the housing 28 to an open state.

  Similarly to the above, in each of the above embodiments, for example, as shown in FIG. 3, the check valve body 24 is attached to and detached from the check valve seat 29 to open and close the inlet port 26. However, instead of this, when the check valve body is displaced in the W2 direction as shown in FIG. 3C, the opening of the radial hole 56a of the first communication hole 56 is, for example, formed by the inner surface of the housing 28. When the closed valve body is closed and the check valve body is displaced in the W1 direction as shown in FIGS. 3A and 3B, the opening of the radial hole 56a of the first communication hole 56 is opened. For example, the inlet port 26 may be opened and closed by switching from the inner surface of the housing 28 to the open state.

  Moreover, in each said embodiment, although what provided the overflow prevention check valve in the high pressure gas filling output system 11 shown in FIG. 1 was mentioned as an example, it can provide and use in apparatuses other than this.

  As described above, the overflow check valve according to the present invention improves the durability of the check valve body and the overflow prevention valve body, and prevents the occurrence of unstable behavior and simplification. In addition, it has an excellent effect of saving space and is suitable for application to such an overflow check check valve.

2 High-pressure tank 11 High-pressure gas filling output system 12 Filling-side check valve 13 Output-side filter 14 Solenoid valve (open / close valve)
DESCRIPTION OF SYMBOLS 15 Overflow prevention check valve 16 Valve block 17 External connection port 18 Output line 18a Output port side line 19 Filling line 20 Junction point 21 Overflow prevention valve 22 Output side check valve 23 Overflow prevention valve body 24 For check Valve body 24a Collar portion 25 Overflow prevention valve seat 26 Inlet port 27 Outlet port 28 Housing 29 Check valve seat 30 Spring member 31 Valve body hole 31a Large diameter hole 31b Small diameter hole 31c Medium diameter hole 32 Second communication hole 32a Radial direction Hole 32b Axial hole 34 Step part 35 Arrow 53 Check valve restrictor 54 Overflow prevention valve restrictor 55 Stopper part 56 First communication hole 56a Radial hole 56b Axial hole 58 Overflow check check valve

Claims (4)

In an overflow check valve comprising a housing having an inlet and an outlet,
The reverse provided movably between an open position that allows a forward gas flow from the inlet to the outlet and a closed position that prevents a reverse gas flow from the outlet to the inlet. A stop valve,
A stopper provided in the housing for restricting the forward movement of the check valve body at the open position;
A valve body for preventing overflow that prevents the forward flow of gas when a differential pressure between the pressure at the inlet and the pressure at the outlet is equal to or higher than a preset differential pressure;
An urging member that urges the overflow preventing valve body in the reverse direction and urges the check valve body in the reverse direction to move toward the closed position;
The overflow prevention check valve, wherein the check valve body and the overflow prevention valve body are separate bodies. The overflow preventing valve body has a flange portion for arranging the urging member,
The urging member is formed of a single member, and urges the overflow preventing valve body in the reverse direction, and directs the check valve body to the closed position via the overflow preventing valve body. 2. The check valve according to claim 1, wherein the check valve is urged in the reverse direction so as to make it move. The overflow check valve according to claim 1, wherein a pressure receiving area of the check valve body is larger than a pressure receiving area of the overflow prevention valve body.   The non-return valve body contacts the stopper when the flow rate is smaller than the rated maximum flow rate, and the overflow prevention valve body allows the forward flow of gas when the flow rate is excessively larger than the rated maximum flow rate. 3. The overflow prevention reverse according to claim 1, wherein a pressure receiving area of the check valve body, a pressure receiving area of the overflow prevention valve body, and a spring constant of the urging member are set so as to prevent. Stop valve.

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