JP5848724B2 - Valve device with overflow prevention function - Google Patents

Description

  The present invention relates to a valve device with an overflow prevention function that can close a main passage when a large amount of fluid flows in the main passage.

  Gas consumers such as gas engines and fuel cells that consume gas and generate driving force and power are known. The gas consumer is connected to the pressure vessel via a valve device, and the valve device can switch the supply and stop of gas from the pressure vessel to the gas consumer. As such a valve apparatus, there exists a thing like patent document 1, for example.

  In the valve device of Patent Document 1, a main stop valve and an overflow prevention valve are connected in series to a fuel supply path that connects an engine and a gas container. The main stop valve opens and closes the fuel supply path according to the on / off operation of the engine switch, and the overflow prevention valve closes the fuel supply path when the pressure difference before and after it increases, and gas from the gas container to the engine The supply of is to be stopped. Therefore, even if the main stop valve is not closed when a large amount of gas flows out due to damage to the piping of the fuel supply path, the fuel supply path is closed by the overflow prevention valve.

JP 2002-115798 A

  In the valve device described in Patent Document 1, since the overflow prevention valve is disposed in the fuel supply path, the gas having the same flow rate as the main stop valve flows through the overflow prevention valve. Therefore, it is necessary to use a valve having a size that can withstand such a large flow rate of gas. However, the external dimensions of the overflow prevention valve that can withstand such a large flow rate gas are large, and the pressure resistance performance needs to be increased, resulting in an increase in cost. Furthermore, since the overflow prevention valve is interposed in the main passage (fuel supply passage) connecting the gas consumer and the gas container, the pressure loss in the main passage increases.

  Accordingly, an object of the present invention is to provide a valve device with an overflow prevention function that can reduce the size of the overflow prevention valve and can reduce the pressure loss of the main passage.

  The valve device with an overflow prevention function according to the present invention is interposed in a throttle formed in a pilot passage connected to a fluid supply source for supplying fluid, a main passage connected to the fluid supply source, and A main valve that closes the main passage when a pilot pressure, which is a pressure downstream of the throttle of the pilot passage, increases and a differential pressure between the pilot pressure and the supply pressure of the fluid supply source decreases, and the pilot valve An electromagnetic on-off valve that opens and closes the pilot passage in response to an input command, and is interposed in the bypass passage; and a bypass passage that connects the downstream side of the throttle and the downstream side of the main valve of the main passage. When the flow rate of the fluid flowing through the bypass passage exceeds a predetermined value, the bypass passage is closed and the pilot pressure is increased, so that the difference between the pilot pressure and the supply pressure is increased. And excess flow valve to reduce, it shall have a.

  According to the present invention, since the main passage and the bypass passage are connected to the same fluid supply source and the bypass passage is connected to the downstream side of the main valve body of the main passage, the flow rate of the bypass passage corresponds to the flow rate of the main passage. ing. Therefore, if the flow rate of the main passage becomes excessive, the flow rate of the bypass passage also becomes excessive. The overflow prevention valve closes the bypass passage to increase the pilot pressure when the flow rate of the bypass passage becomes excessive and exceeds a predetermined value, and causes the main valve to close the main passage. Therefore, the overflow prevention function of the main passage can be achieved by the overflow prevention valve provided in the bypass passage.

  In the present invention, the bypass passage is connected to the pilot passage, and the throttle is interposed in the pilot passage. Therefore, since the flow rate flowing through the bypass passage is less than that of the main passage, a small flow rate type overflow prevention valve can be employed. Thereby, size reduction and cost reduction of a valve apparatus can be achieved. Further, since the overflow prevention valve is interposed in the bypass passage, the pressure loss in the main passage can be reduced as compared with the conventional case where the overflow prevention valve is interposed in the main passage.

  In the above invention, the overflow prevention valve may be arranged upstream of the electromagnetic on-off valve in the bypass passage.

  If the said structure is followed, it can prevent that the fluid of an excessive flow volume flows into an electromagnetic on-off valve.

  In the above invention, the fluid supply source may be a pressure vessel, and the overflow prevention valve may be disposed in the pressure vessel.

  According to the above configuration, the overflow prevention valve can be protected by the pressure vessel. Thereby, for example, when a large impact is applied to the valve device, the overflow prevention valve is damaged and the overflow prevention function does not work, and the fluid in the pressure vessel can be prevented from leaking out.

  In the above invention, the electromagnetic on-off valve may be disposed outside the pressure vessel.

  If the said structure is followed, since the electromagnetic on-off valve is arrange | positioned out of the pressure vessel, the diameter of a pressure vessel can be made small and the external dimension of a pressure vessel can be made small.

  In the above invention, the main valve moves between a closed position that closes the main passage and an open position that opens the main passage according to a differential pressure between the pilot pressure and the supply pressure, and You may have the direct-acting type bearing member which supports the said main valve body so that a movement to a closed position and the said open position is possible.

  If the said structure is followed, the sliding resistance and wear of a valve body can be reduced, and the responsiveness and durability of a main valve can be improved.

  According to the present invention, the overflow prevention valve can be reduced in size, and the pressure loss in the main passage can be reduced.

It is sectional drawing which shows the valve apparatus which concerns on 1st Embodiment of this invention. It is the circuit diagram which showed the structure of the valve apparatus of FIG. 1 typically. It is sectional drawing which expands and shows the overflow prevention valve of the valve apparatus of FIG. It is a graph which shows the relationship between the main flow volume of a valve apparatus, and various values. It is the circuit diagram which showed typically the structure of the valve apparatus which concerns on 2nd Embodiment of this invention.

  Hereinafter, a valve device 1 according to an embodiment of the present invention will be described with reference to the drawings. In addition, the concept of the direction used in the following description is used for convenience in description, and does not limit the direction of the configuration of the invention in that direction. Moreover, the valve apparatus 1 demonstrated below is only one Embodiment of this invention. Therefore, the present invention is not limited to the embodiments, and additions, deletions, and changes can be made without departing from the spirit of the invention.

  A gas consumer such as a gas engine or a fuel cell consumes gas supplied thereto to generate driving force, and a tank 2 as shown in FIG. 1 is connected to the gas consumer. Yes. In the tank 2 which is a fluid supply source and a pressure vessel, a fluid to be supplied to the gas consumer, specifically, a gas such as natural gas or hydrogen gas is stored, and the opening 2a is closed. The valve device 1 is screwed together. The valve device 1 opens and closes between the gas consumer and the tank 2 in accordance with a command from a control unit (not shown). Further, the valve device 1 is configured to close the gap between the gas consumer and the tank 2 to stop the outflow of gas when a gas having a flow rate larger than a predetermined flow rate flows out of the tank 2. Has a flow prevention function. Below, the specific structure of the valve apparatus 1 is demonstrated.

  The valve device 1 includes a housing 11, a main valve 12, a pilot electromagnetic valve 13, and an overflow prevention valve 14. The housing 11 has an in-tank part 11a and an on-tank part 11b, and the in-tank part 11a is formed in a substantially cylindrical shape. The in-tank portion 11 a is screwed in a sealed state to the inner peripheral portion of the opening 2 a of the tank 2, and is disposed in the tank 2 so that its axis L 1 coincides with the axis of the tank 2. One end of the in-tank portion 11a faces the outside of the tank 2, and an on-tank portion 11b is integrally provided there. The on-tank part 11b has a substantially cylindrical shape, and is arranged so that its axis L2 is orthogonal to the axis L1 of the in-tank part 11a. The length of the on-tank portion 11b in the axial direction is larger than the outer diameter of the opening 2a, and the on-tank portion 11b is disposed outside the opening 2a.

  The housing 11 thus configured has a plurality of ports 21, 26, 29 and passages 23, 28, 41, and the passages 23, 28, 41 have a main valve 12, a pilot solenoid valve 13, and Overflow prevention valves 14 are interposed. More specifically, a pilot port 21 is formed at the other end of the in-tank portion 11a of the housing 11 (the end in the tank 2). The pilot port 21 is formed around the axis L <b> 1 and is connected to the pilot passage 23 via the first filter 22. The pilot passage 23 is a passage extending upward along the axis L1, and a throttle 24 is formed in a downstream portion thereof. Further, the downstream side of the pilot passage 23 is connected to the first valve space 25, and the gas guided to the pilot passage 23 is guided to the first valve space 25 through the throttle 24. The first valve space 25 is a space having a circular cross section extending upward along the axis L <b> 1, and the hole diameter of the first valve space 25 is formed larger than the hole diameter of the throttle 24.

  The housing 11 has an inflow port 26 formed on the other end side of the side surface of the in-tank portion 11a. The inflow port 26 extends over the entire circumference in the side surface of the in-tank portion 11 a and is connected to the main passage 28 via the second filter 27. The main passage 28 has an upstream portion 28a and a downstream portion 28b. The upstream portion 28a communicates the inflow port 26 with the first valve space 25, and the downstream portion 28b has a first valve. The space 25 and the outflow port 29 are communicated with each other. The downstream portion 28b has a first valve port 30 connected to the first valve space 25, extends upward along the axis L1 from the first valve port 30, and further bends at a substantially right angle therefrom. It extends parallel to the axis L2 and is connected to the outflow port 29. The outflow port 29 is formed at one end in the axial direction of the on-tank portion 11b, connected to a pipe or the like, and connected to a gas consumer via a control valve, a pressure adjustment valve, or the like (not shown). The main valve 12 is provided in the first valve space 25 interposed between the upstream portion 28 a and the downstream portion 28 b of the main passage 28.

The main valve 12 has a primary pressure p ₁ (see FIG. 2) that is the pressure of the gas flowing through the upstream portion 28 a of the main passage 28 (ie, the supply pressure of the tank 2) and the pilot pressure p ₃ that is guided through the throttle 24. The main passage 28 is configured to open and close according to the differential pressure with respect to (see FIG. 2). The main valve 12 includes a first valve body 31 and a first urging member 32, and the first valve body 31 is formed in a substantially cylindrical shape. The first valve body 31 is accommodated in the first valve space 25 and is slidably supported by the housing 11. A first valve seat 33 is formed around the first valve port 30 of the housing 11. When the first valve body 31 is moved to the closed position, the first valve seat 33 is seated on the first valve seat 33. 30 is closed, that is, the main passage 28 is closed (see FIG. 1). When the first valve body 31 is moved to the open position, the first valve port 30 is opened away from the first valve seat 33, that is, the main passage 28 is opened.

Further, the outer diameter of the distal end portion of the first valve body 31 is smaller than the outer diameter of the proximal end portion, and an annular primary pressure chamber 34 is formed radially outward of the distal end portion. Is formed. The primary pressure chamber 34 is connected to the upstream portion 28a of the main passage 28, the gas in the tank 2 is led through the inlet port 26 and the upstream portion 28a, i.e., so the primary pressure p ₁ is derived ing. The primary pressure chamber 34 is connected to the downstream portion 28b by moving the first valve body 31 to the open position and opening the first valve port 30, and is connected to the primary pressure chamber 34 by connecting. The gas thus introduced is guided to the downstream portion 28b.

  A pilot chamber 35 is formed below the first valve body 31, and a first urging member 32 is provided in the pilot chamber 35. The first urging member 32 urges the first valve body 31 so as to close the first valve port 30, that is, urges the first valve body 31 toward the closed position. The pilot chamber 35 is connected to the throttle 24 of the pilot passage 23 so that the gas in the tank 2 is guided to the pilot chamber 35 through the throttle 24. A seal member 36 is provided on the outer peripheral portion of the proximal end side of the first valve body 31 so as to seal between the pilot chamber 35 and the primary pressure chamber 34, and the first valve body 31 is provided by the seal member 36. And the housing 11 are sealed so that the pilot chamber 35 is separated from the primary pressure chamber 34.

In the main valve 12 configured as described above, the first valve body 31 receives the primary pressure p ₁ guided to the primary pressure chamber 34 and the pilot pressure p ₃ guided to the pilot chamber 35 as shown in FIG. ing. The first valve body 31 also receives a secondary pressure p ₂ that is the pressure of the gas flowing through the downstream portion 28b of the main passage 28, and the secondary pressure p ₂ is in the open position together with the primary pressure p _1. It acts on the first valve body 31 to move it. The pilot pressure p ₃ acts on the first valve body 31 so as to move to the closed position together with the urging force of the first urging member 32. That is, the biasing force of the pilot pressure p ₃ and the first biasing member 32 is acting on the first valve body 31 to resist primary pressure p ₁ and the secondary pressure p _2. Thus, the first valve body 31 is adapted to move to a position where these forces are balanced, for example, the pilot pressure p ₃ becomes lower when moving towards the open position, the closed position when the pilot pressure p ₃ increases It moves to the direction. The pilot chamber 35 which is the pilot pressure p ₃ is guided, a bypass passage 41 is connected as shown in FIG. 1, the bypass passage 41, connects the downstream portion 28b of the pilot chamber 35 and the main passage 28 doing.

  A second valve space 42 and a third valve space 43 are interposed in the bypass passage 41. The second valve space 42 is formed in the on-tank portion 11b, and the third valve space 43 is formed in the in-tank portion 11a. The bypass passage 41 is divided into three portions 41a, 41b, 41c by these two valve spaces 42, 43. The upstream portion 41a connects the pilot chamber 35 and the third valve space 43, the intermediate portion 41b connects the third valve space 43 and the second valve space 42, and the downstream portion 41c connects the second valve space 42. And the downstream portion 28b of the main passage 28 are connected. The downstream portion 41c of the bypass passage 41 is formed along the axis L2 together with the second valve space 42, and the second valve space 42 is connected to the second valve port 44 of the downstream portion 41c. Moreover, the 2nd valve space 42 has the opening 42a in the base end side of the in-tank part 11a, and the pilot solenoid valve 13 is inserted from the opening 42a.

  The pilot solenoid valve 13, which is an electromagnetic on-off valve, opens or closes the second valve port 44 in response to a command from a control unit (not shown), that is, opens and closes the bypass passage 41. The pilot electromagnetic valve 13 having such a function includes an electromagnetic solenoid 51, a second valve body 52, and a second urging member 53. The electromagnetic solenoid 51 is excited in accordance with a command from a control unit (not shown), and includes a case 61, a fixed magnetic pole 62, and a coil 63. The case 61 has a substantially cylindrical shape, and a fixed magnetic pole 62 is fitted in one opening of the case 61 so as to close the case. The fixed magnetic pole 62 is made of a magnetic material. A coil 63 is fitted on the inner periphery of the case 61. The coil 63 is electrically connected to a control unit (not shown) and is excited according to a current (that is, a command) supplied from the control unit. A substantially cylindrical guide member 64 made of a nonmagnetic material is fitted on the inner peripheral portion of the coil 63. The electromagnetic solenoid 51 configured as described above is inserted into the opening 42 a of the second valve space 42 with the other opening of the case 61 facing the second valve port 44. A second valve body 52 is inserted into the guide member 64 of the electromagnetic solenoid 51.

  The second valve body 52 has a generally cylindrical shape and is supported by the guide member 64 so as to be slidable along the axis L2. A tip side portion of the second valve body 52 protrudes from the electromagnetic solenoid 51 toward the second valve port 44, and a second valve seat 45 is formed around the second valve port 44. When the second valve body 52 is moved to the closed position, the second valve body 52 is seated on the second valve seat 45 to close the second valve port 44, that is, the bypass passage 41 is closed. Further, when the second valve body 52 is moved to the open position, it is separated from the second valve seat 45 and opens the second valve port 44, that is, opens the bypass passage 41.

  A second urging member 53 is provided between the base end of the second valve body 52 thus configured and the fixed magnetic pole 62, and is urged toward the closed position by the second urging member 53. It is energized. Further, the outer diameter of the distal end portion of the second valve body 52 is smaller than the outer diameter of the proximal end portion, and an annular valve chamber 54 is formed radially outward of the distal end portion. Has been. The valve chamber 54 is connected to the intermediate portion 41 b of the bypass passage 41, and is connected to the pilot chamber 35 via the intermediate portion 41 b and the third valve space 43. Further, the valve chamber 54 is connected to the downstream portion 41 c of the bypass passage 41 by moving the second valve body 52 to the open position and opening the second valve port 44.

In the pilot solenoid valve 13 configured as described above, when a current is passed through the coil 63 of the electromagnetic solenoid 51 to excite the coil 63, the second valve body 52 is attracted by the fixed magnetic pole 62 and moves to the open position. As a result, the bypass passage 41 is opened, and the pilot chamber 35 and the downstream portion 28 b of the main passage 28 communicate with each other through the bypass passage 41. By communicating, the gas flow is pilot pressure p ₃ generated decreases the bypass passage 41. Thereby, the 1st valve body 31 of the main valve 12 moves to an open position, and the main channel | path 28 opens. When the current flowing in the coil 63 of the electromagnetic solenoid 51 is stopped and the coil 63 is demagnetized, the second valve body 52 is urged by the second urging member 53 and moves to the closed position as shown in FIG. Thus, stops the flow of gas in the bypass passage 41 with the bypass passage 41 is closed, the pilot pressure p ₃ rises. Thereby, the 1st valve body 31 moves to a closed position, and the main channel | path 28 closes.

  As described above, in the valve device 1, the first valve body 31 of the main valve 12 is moved to the open position and the closed position by opening and closing the main passage 28 by flowing or stopping the current to the pilot electromagnetic valve 13. Can be done. In the valve device 1 that can operate the main valve 12 in this way, an overflow prevention valve 14 is further provided in the third valve space 43.

  The overflow prevention valve 14 is configured to close the bypass passage 41 when the flow rate of the gas flowing through the bypass passage 41 exceeds a predetermined flow rate. As shown in FIG. Member 72. The third valve body 71 is generally formed in a columnar shape, and the outer diameter of the base end portion 71b is larger than the outer diameter of the distal end portion 71a. The distal end portion 71 a of the third valve body 71 is inserted into the downstream portion 43 a of the third valve space 43 and is slidably supported by the housing 11.

  Moreover, the hole diameter of the upstream part 43b of the 3rd valve space 43 is formed larger diameter than the hole diameter of the said downstream part 43a, The base end side part of the 3rd valve body 71 is formed in this upstream part 43b. 71b is arranged. A third valve seat 47 is formed around the third valve port 46 connecting the upstream portion 43b and the downstream portion 43a of the third valve space 43, and the third valve body 71 is in the closed position. The base end portion 71b is seated on the third valve seat 47 and the third valve port 46 is closed. Further, when the third valve body 71 is moved to the open position, the proximal end portion 71b of the third valve body 71 is separated from the third valve seat 47 and the third valve port 46 is opened. At this time, the third valve body 71 contacts the housing 11 and closes the opening of the upstream portion 41 a of the bypass passage 41. Therefore, a first communication passage 48 is formed in the proximal end portion 71 b of the third valve body 71. The first communication passage 48 is formed so as to connect the upstream portion 41 a of the bypass passage 41 and the upstream portion 43 b of the third valve space 43 when the third valve body 71 is located at the closed position.

On the other hand, a second communication passage 49 is formed in the distal end portion 71 a of the third valve body 71. The second communication passage 49 has three openings 49 a to 49 c, and one of the openings 49 a is always connected to the downstream portion 43 a of the third valve space 43. The remaining two openings 49b and 49c are basically connected to the upstream portion 43b. However, when the third valve body 71 moves to the closed position and the third valve port 46 is closed, the upstream portion 43b is connected to the upstream portion 43b. It is designed to be blocked. In addition, a throttle 49d is interposed in the second communication passage 49, and when the gas in the bypass passage 41 flows, the pressure difference p ₃ −p according to the gas flow rate on the upstream side and the downstream side of the overflow prevention valve 14. ₄ is generated. That is, as the gas flow rate in the bypass passage 41 increases, the pressure difference p ₃ −p ₄ increases.

The third valve body 71 configured as described above is urged toward the open position by the third urging member 72 provided in the downstream portion 43a of the third valve space 43. Is basically located in the open position. The third valve body 71 receiving a pilot pressure p ₃ that is the upstream side pressure at its proximal end, is adapted to receiving the downstream pressure p ₄ at the tip. Pilot pressure p ₃ and the downstream pressure p ₄ is applied to the third valve body 71 to resist one another, the third valve body 71, the differential pressure of the pilot pressure p ₃ and the downstream pressure p ₄ (i.e. The pressure difference between the front and rear of the overflow prevention valve 14) and the urging force of the third urging member 72 are balanced. That is, the third valve body 71, the flow rate of gas flowing through the bypass passage 41 (i.e., the pilot flow rate q) equal to or greater than a predetermined flow rate _{q trip} and increases (i.e., the pressure of the pilot pressure _{p 3} and the downstream pressure _{p 4} When the difference p ₃ −p ₄ becomes _{equal to} or greater than the predetermined pressure Δp _trip ), the valve moves to the closed position and closes the bypass passage 41. By the bypass passage 41 is closed, the pilot pressure p ₃ rises as if closing the bypass passage 41 by the pilot solenoid valve 13. Thereby, the 1st valve body 31 moves to a closed position, and the main channel | path 28 is closed.

In the valve device 1 configured as described above, the upstream side of the bypass passage 41 is connected to the tank 2 via the pilot passage 23, and the downstream side thereof is connected to the downstream portion 28 b of the main passage 28. That is, as shown in FIG. 2, the bypass passage 41 is configured to bypass the upstream portion 28 a and the downstream portion 28 b of the main passage 28, and the tank 2 is supplied with a common supply pressure source with the main passage 28. It is said. Therefore, the pilot flow rate q (see the one-dot chain line in FIG. 4) increases and decreases to correspond to the increase and decrease in the flow rate Q of the gas flowing through the main passage 28, that is, the main flow rate Q (see the solid line in FIG. 4) as shown in FIG. To do. In FIG. 4, the solid line indicates the relationship between the pressure difference p ₁ -p ₂ before and after the main valve 12 and the main flow rate Q, and the broken line indicates the pressure difference p ₃ -p ₄ before and after the overflow prevention valve 14 and the main flow rate Q. And the alternate long and short dash line indicate the relationship between the pilot flow rate q and the main flow rate Q, the vertical axis indicates the pressure difference and the pilot flow rate q, and the horizontal axis indicates the main flow rate Q.

Since the flow rates of the gas flowing through the passages 28 and 41 correspond to each other, the pilot flow rate q becomes equal to or higher than the predetermined flow rate q _trip (ie, the difference between the pilot pressure p ₃ and the downstream pressure p ₄ ). By configuring the overflow prevention valve 14 to close the bypass passage 41 when the pressure p ₃ -p ₄ becomes equal to or higher than the predetermined pressure Δp _trip ), the main valve 12 can be operated when the main flow rate Q becomes excessive. The first valve body 31 moves to the closed position and the main passage 28 is closed. As a result, even if a large amount of gas leaks from the main passage 28 due to damage to the main passage 28 and pipes disposed downstream of the main passage 28, the pilot solenoid valve 13 does not need to be given a valve closing command ( That is, the main passage 28 can be automatically closed (without stopping the current flowing through the pilot solenoid valve 13). Therefore, it is possible to prevent the gas in the tank 2 from leaking through the main passage 28 when the main passage 28 and a pipe disposed downstream thereof are damaged.

  Thus, in the valve device 1, the overflow prevention function of the main passage 28 is achieved by providing the overflow prevention valve 14 in the bypass passage 41 different from the main passage 28. The bypass passage 41 is connected to the pilot passage 23, and the flow rate of the gas flowing from the main passage 28 is small. Since the overflow prevention valve 14 is provided in the bypass passage 41 where the flow rate of the flowing gas is small, the overflow prevention valve 14 having a small applicable flow rate can be used. Therefore, the outer dimension of the overflow prevention valve 14 can be reduced, that is, the overflow prevention valve 14 can be reduced in size and the manufacturing cost can be reduced. Moreover, since the overflow prevention valve 14 is provided in the bypass passage 41, the pressure loss of the main passage 28 can be reduced, and the use limit pressure of the tank 2 can be reduced.

  As shown in FIG. 1, in the valve device 1, the third valve space 43 in which the overflow prevention valve 14 is provided is formed in the in-tank portion 11 a, and the overflow prevention valve 14 is disposed in the tank 2. Yes. Therefore, the overflow prevention valve 14 can be protected by the tank 2, and the overflow prevention valve 14 can be prevented from being damaged when a large impact is applied to the valve device 1. Thereby, it can prevent that the overflow prevention valve 14 is damaged and an overflow prevention function does not work, and when the valve apparatus 1 is damaged, it can prevent that a large amount of gas leaks out from the main channel | path 28. . The second valve space 42 in which the pilot solenoid valve 13 is provided is formed in the on-tank portion 11 b, and the pilot solenoid valve 13 is disposed outside the tank 2. Thereby, it can prevent that the aperture diameter of the opening part 2a of the tank 2 becomes large, and the external dimension of the tank 2 can be made small.

  Further, in the valve device 1 of the present embodiment, since the overflow prevention valve 14 is arranged on the upstream side of the pilot electromagnetic valve 13, it is possible to prevent an excessively large flow of gas from being guided to the pilot electromagnetic valve 13. .

  In addition, although the case where gas was mainly supplied from the tank 2 to the gas consumer (not shown) was described for the valve device 1, the overflow prevention valve 14 is provided in the bypass passage 41 in the valve device 1. The tank 2 can be filled with gas by supplying high-pressure gas from a filling port (not shown) to the downstream portion 28 b of the main passage 28.

[Second Embodiment]
The valve device 1A of the second embodiment is similar in configuration to the valve device 1 of the first embodiment. Below, about the structure of 1 A of valve apparatuses of 2nd Embodiment, a different point from the structure of the valve apparatus 1 of 1st Embodiment is mainly demonstrated, the same code | symbol is attached | subjected about the same structure and description is abbreviate | omitted. There is a case.

  In the valve device 1A of the second embodiment, as shown in FIG. 5, an overflow prevention valve 14A and a pilot electromagnetic valve 13 are interposed in the bypass passage 41A, and the overflow prevention valve 14A is located downstream of the pilot electromagnetic valve 13. positioned. A main valve 12 </ b> A is interposed in the main passage 28, and the main valve 12 </ b> A has a first valve body 31, a first urging member 32, and a bearing member 37. The bearing member 37 is a direct-acting bearing member such as a ball bearing or a sliding bearing, and is externally mounted on the tip side portion of the first valve body 31. The bearing member 37 is fixed to the housing 11 and supports the first valve body 31 so that it can move smoothly in the vertical direction. Thus, by supporting the 1st valve body 31 by the bearing member 37, the sliding resistance and wear of the 1st valve body 31 can be reduced, and the responsiveness and durability of the main valve 12A can be improved. it can.

In the valve device 1A configured as described above, when a large amount of gas flows in the main passage 28 as in the valve device 1 of the first embodiment, a gas having a flow rate corresponding to the gas flows also in the bypass passage 41A. When q becomes _{equal to} or greater than q _trip , the bypass passage 41A is closed by the overflow prevention valve 14A. As a result, the pilot pressure p ₃ rises, the first valve body 31 is pushed to the closed position, and is seated on the first valve seat 33. As a result, the main passage 28 is closed and gas can be prevented from leaking from the main passage 28.

  Note that the valve device 1A of the second embodiment can also be realized by adopting a pilot solenoid valve with an overflow prevention valve in which an overflow prevention valve 14A is incorporated in the pilot solenoid valve 13. In this case, the pilot solenoid valve with an overflow prevention valve can be protected by disposing the pilot solenoid valve with an overflow prevention valve in the tank 2 in order to protect the pilot solenoid valve with an overflow prevention valve.

  In addition, the valve device 1 </ b> A of the second embodiment has the same effects as the valve device 1 of the first embodiment.

[Other forms]
In the valve device 1 according to the first embodiment, the bypass passage 41 is connected to the pilot passage 23 via the pilot chamber 35, but the pilot chamber 35 is not necessarily interposed between the pilot passage 23 and the bypass passage 41. . For example, the pilot passage 23 may be branched downstream of the throttle 24, one passage may be connected to the pilot chamber 35, and the other passage may be connected to the bypass passage 41. In the valve devices 1 and 1A of the first and second embodiments, the pilot port 21 and the inflow port 26 are formed separately, but the two ports 21 and 26 are connected by connecting the pilot passage 23 to the main passage 28. May be shared.

  Further, in the valve devices 1 and 1A of the first and second embodiments, the case where the valve device 1 is provided in the opening 2a of the tank 2 has been described. It may be provided on things. In the first and second embodiments described above, gas is handled as a fluid, but the fluid may be a liquid such as oil or water.

1, 1A Valve device 2 Tank 12, 12A Main valve 13 Pilot solenoid valve 14, 14A Overflow prevention valve 23 Pilot passage 24 Throttle 28 Main passage 31 First valve body 37 Bearing member 41 Bypass passage

Claims (5)

A restriction formed in a pilot passage connected to a fluid supply for supplying fluid;
The pilot pressure that is interposed in the main passage connected to the fluid supply source and is downstream from the throttle of the pilot passage is increased, and the difference between the pilot pressure and the supply pressure of the fluid supply source is reduced. A main valve that closes the main passage,
An electromagnetic on-off valve that is interposed in a bypass passage connecting the downstream side of the throttle of the pilot passage and the downstream side of the main valve of the main passage, and opens and closes the pilot passage according to an input command;
When the flow rate of the fluid flowing through the bypass passage exceeds a predetermined value, the excess flow closes the bypass passage and increases the pilot pressure to reduce the difference between the pilot pressure and the supply pressure. And a valve device with an overflow prevention function.   The valve device with an overflow prevention function according to claim 1, wherein the overflow prevention valve is disposed upstream of the electromagnetic on-off valve in the bypass passage. The fluid supply source is a pressure vessel;
The valve device with an overflow prevention function according to claim 1 or 2, wherein the overflow prevention valve is disposed in the pressure vessel.   The valve device with an overflow prevention function according to claim 3, wherein the electromagnetic on-off valve is disposed outside the pressure vessel. The main valve includes a main valve body that moves between a closed position that closes the main passage and an open position that opens the main passage according to a differential pressure between the pilot pressure and the supply pressure, the closed position, and the The valve device with an overflow preventing function according to any one of claims 1 to 4, further comprising a direct acting bearing member that supports the main valve body so as to be movable to an open position.

Images