Check valve and valve device

Abstract

The present invention suppresses the occurrence of chattering in a check valve. A check valve 90 is used in a valve device 60 attached to a tank 20 for storing hydrogen. The check valve 90 is disposed in a filling passage 61 which is formed in a housing 81 of the valve device 60 and which allows hydrogen to be filled in the tank 20 to pass therethrough. The check valve 90 includes a valve body 84, a valve seat 82 formed in the housing 81, and a valve spring 80 for pressing the valve body 84 toward the valve seat 82. The valve body 84 includes a body portion 84c, a valve portion 84a seated on the valve seat 82 at closing of the valve, and a large diameter portion 84b that is formed between the body portion 84c and the valve portion 84a and that has an outer diameter larger than that of the body portion 84c. The valve portion 84a has a projection section 86 that is a projection projecting to the upstream side of the filling passage 61 relative to a seat portion 85 abutting on the valve seat 82 at the closing of the valve, and forms an upstream-side throttle section 91 between the projection section 86 and the filling passage 61 at opening of the valve.

Description

[0001] [Document name] Statement

[0002] [Title of invention] Check valve and valve device

[0003] [Technical Field]

[0004]

[001] The present invention relates to a check valve used in a tank system filled with hydrogen, and a valve system equipped with the check valve.

[0005] [Background technology]

[0006] [. 0 0 2] Conventionally, electrochemical cells that generate electricity through a chemical reaction between hydrogen and oxygen are known. Fuel cells are one example of electrochemical cells. One application of fuel cells is a fuel cell system that is installed in a vehicle and supplies power to the vehicle's driving motor. Such fuel cell systems use a tank to store hydrogen as fuel gas. Hydrogen is filled into the tank at a hydrogen station, for example, by fitting a hydrogen supply nozzle extending from a hydrogen filling device into a receptacle for receiving hydrogen supply from the fuel cell vehicle, and supplying hydrogen toward the fuel cell vehicle's tank. The hydrogen filling path is provided with a check valve that operates when open so that hydrogen flows only from the receptacle to the tank.

[0007]

[0003] Meanwhile, the supply of hydrogen from the tank to the fuel cell is controlled by a control valve or the like with an opening and closing mechanism. This control valve and the valves in the filling path are combined into a single valve device as an interface connecting the tank with the outside, which is advantageous from the standpoint of ease of installation, cost, etc. (See, for example, the valve unit in Patent Document 1.)

[0008] [Prior art documents]

[0009] [Patent documents]

[0010]

〇 0 0 4

[0011] [Patent Document 1] JP 2019-116929 A

[0012] Summary of the Invention

[0013] [Problem to be solved by the invention]

[0014]

[0005] In a check valve installed in the hydrogen filling path, the valve disc is pressed in the closing direction by the spring setter and the hydrogen pressure on the tank side. On the other hand, when hydrogen is supplied from the receptacle, the valve disc is pressed in the opening direction by the pressure of the supplied hydrogen. Then, when the pressing force in the opening direction exceeds the pressing force in the closing direction, the check valve opens. Furthermore, the hydrogen pressure acting on the check valve in the closing direction differs depending on the degree of hydrogen filling in the tank.

[0015] [0 0 0 6] When hydrogen is supplied from the receptacle, immediately after the check valve opens, hydrogen flows rapidly to the downstream side of the valve disc, which can cause a rapid drop in hydrogen pressure upstream of the valve disc. When the hydrogen pressure upstream of the valve disc drops rapidly, the pressure difference between the upstream and downstream sides of the valve disc becomes small, which can cause the check valve to close due to the load of the spring. When the check valve closes, the pressure upstream of the valve disc rises again, causing the check valve to open again. After the check valve opens again, the pressure upstream of the valve disc drops rapidly, causing the check valve to close again. In this way, when hydrogen is supplied from the receptacle, the check valve may repeatedly open and close, a phenomenon known as chattering.

[0016] [0 0 7] Chattering can prevent smooth hydrogen filling, as well as cause other inconveniences such as noise generation or accelerated wear at contact points.

[0017]

[0008] The present invention has been made against the background of the above-mentioned problems, and aims to provide a check valve that does not chatter when filling a tank with hydrogen, and a valve device equipped with such a check valve.

[0018] [Means for solving the problem]

[0019]

[0009] According to the present invention, there is provided a check valve (90) used in a valve device (60) attached to a tank (20) for storing hydrogen, the check valve (90) being disposed in a filling passage (61) formed in a housing (81) of the valve device (60) and through which the hydrogen to be filled into the tank (20) passes, the check valve (90) including a valve element (84), a valve seat (82) formed in the housing (81), and a valve spring (80) for pressing the valve element (84) against the valve seat (82), the valve element (84) including a main body (84c) and a valve spring (80) for pressing the valve seat (82) when the valve is closed. a valve portion (84a) seated on the valve seat (82) and a large-diameter portion (84b) formed between the main body portion (84c) and the valve portion (84a) and having an outer diameter larger than that of the main body portion (84c), wherein the valve portion (84a) has a protrusion (86) that protrudes toward the upstream side of the filling passage (61) beyond a seat portion (85) that abuts against the valve seat (82) when the valve is closed, and the check valve (90) forms an upstream throttle portion (91) between the protrusion (86) and the filling passage (61) when the valve is open.

[0020] [Effects of the Invention]

[0021]

[0010] The check valve of the present invention suppresses chattering in the check valve when filling a tank with hydrogen.

[0022] BRIEF DESCRIPTION OF THE DRAWINGS

[0023] [ 0 0 1 1 ]

[0024] [Figure 1] A schematic diagram for explaining an example of the overall configuration of a fuel cell system 1 in which a check valve according to the present invention is used.

[0025] [Figure 2] A diagram for explaining the valve device 6 ○ equipped with a check valve according to the present invention.

[0026] [Figure 3] A diagram showing a schematic diagram of the filling side check valve 9 〇 according to the present invention.

[0027] [Figure 4] Front view of valve body 84.

[0028] [Figure 5] A side view of the valve body 84 shown in Figure 4, viewed from the direction indicated by E.

[0029] [Figure 6] A cross-sectional view along line F-F in Figure 4.

[0030] [Figure 7] A diagram showing the state immediately after the filling side check valve 90 according to the present invention has opened.

[0031] [Figure 8] A diagram showing a conventional filling side check valve 900.

[0032] [Figure 9] A diagram to explain the behavior of the pressure P h in the first passage 61 a when chattering occurs in the conventional filling side check valve 900.

[0033] [Figure 10] A diagram for explaining the behavior of the pressure P h in the first passage 61 a in the filling side check valve 90 of the present invention.

[0034] [Mode for Carrying Out the Invention]

[0035]

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. Note that the components, arrangements, etc. described below do not limit the present invention, and various modifications can be made within the scope of the present invention. In addition, in each drawing, the same reference numerals indicate the same elements, and descriptions thereof are omitted as appropriate. In each drawing, illustrations of detailed parts are simplified or omitted as appropriate. Furthermore, duplicate descriptions are simplified or omitted as appropriate.

[0036]

[0013] Figure 1 is a schematic diagram illustrating an example of the overall configuration of a fuel cell system 1 in which a check valve according to the present invention is used. The fuel cell system 1 includes a tank device 21, a fuel cell 10, an air compressor 30, auxiliary equipment 40, and a consumer device 50. The fuel cell system 1 is, for example, a fuel cell system for a fuel cell vehicle.

[0037]

[0014] Fuel cell 10 is, for example, a polymer electrolyte fuel cell, and is made by stacking multiple single cells, each of which has an MEA (Membrane Electrode Assembly) sandwiched between a pair of conductive separators.

[0038]

[0015] The tank device 21 includes a tank 20, which is a storage container filled with compressed hydrogen, and a valve device 60. The check valve according to the present invention is provided in the valve device 60.

[0039]

[0016] Hydrogen in the tank 20 exits the valve device 60, passes through piping 70, branch 70A, and piping 72, and is supplied to the fuel cell 10 via the auxiliary equipment 40. Although only one tank device 21 is shown in FIG. 1, multiple tank devices 21 may be provided.

[0040]

[0017] Another pipe 71 extending from branch 70A is provided with a receptacle 73 for filling hydrogen into tank device 21. Receptacle 73 is a connector that fits onto the nozzle of a hydrogen filling device when filling hydrogen into tank device 21 from a hydrogen filling device at a hydrogen station, for example.

[0041]

[0018] The air compressor 30 takes in external air, compresses it, and supplies it to the fuel cell 10 via piping 74 and auxiliary equipment 40.

[0042]

[0019] The auxiliary equipment 40 includes a pressure reducing valve that reduces the pressure of hydrogen and an injector that adjusts the amount of hydrogen supplied to the fuel cell 10. The auxiliary equipment 40 also includes a humidifier that humidifies the air supplied from the air compressor 30 and a back pressure valve that controls the pressure. The equipment included in the auxiliary equipment 40 is not limited to these. The equipment included in the auxiliary equipment 40 may also be provided in separate locations rather than being grouped together as the auxiliary equipment 40.

[0043]

[0020] The consumer device 50 is a device that operates using electricity, such as an electric motor, an electronic control device, a sensor, and an actuator. The electric motor is, for example, an electric motor for driving wheels. The consumer device 50 receives power directly or indirectly from the fuel cell 10.

[0044]

[0021] Fig. 2 is a diagram illustrating a valve device 60 equipped with a check valve according to the present invention. The valve device 60 has a housing 81. The housing 81 has a common passage 64, a filling passage 61, and a supply passage 62 as passages through which hydrogen passes.

[0045]

[0022] The valve device 60 has a seal (not shown) between it and the tank 20 that seals the inside and outside of the tank 20. The housing 81 of the valve device 60 has an external connection part 60A, a filling-side tank connection part 60C, and a supply-side tank connection part 60D. The filling-side tank connection part 60C and the supply-side tank connection part 60D are provided in positions that open into the tank 20. In other words, the filling-side tank connection part 60C and the supply-side tank connection part 60D are formed inside the tank 20 with respect to the seal part, in positions facing the hydrogen storage area. On the other hand, the external connection part 60A is provided so as to open to the outside of the tank 20, with the seal part in between.

[0046]

[0023] The piping 70 on the outside of the tank device 21 is connected to the valve device 60 at an external connection part 60A. Inside the valve device 60, one end of a common passage 64 is connected to the external connection part 60A and the other end is connected to a branch 60B. The common passage 64 branches into a filling passage 61 and a supply passage 62 at the branch 60B.

[0047]

[0024] One end of the filling passage 61 is connected to the branch 60B, and the other end is connected to the filling-side tank connection part 60C. The filling passage 61 is provided with a filling-side check valve 90. The filling-side check valve 90 is the check valve of the present invention. When open, the filling-side check valve 90 is a check valve that allows hydrogen to flow only from the branch 60B to the filling-side tank connection part 60C.

[0048]

[0025] One end of supply passage 62 is connected to branch 60B, and the other end is connected to supply-side tank connection part 60D. Supply passage 62 is provided with, in this order from the branch 60B side, a control valve 67, a supply-side check valve 68, and an excess flow valve 65.

[0049]

[0026] The control valve 67 is a solenoid valve that can be switched between open and closed by turning on and off electricity. The control valve 67 adjusts the amount of hydrogen supplied from the tank 20 to the fuel cell 10 in cooperation with a pressure reducing valve, an injector, etc. in the auxiliary equipment 40.

[0050]

[0027] The supply side check valve 68 is a check valve that, when open, allows hydrogen to flow only from the supply side tank connection part 60D to the branch 60B side.

[0051]

[0028] The excess flow valve 65 operates to limit the flow rate when the flow rate of hydrogen flowing from the supply tank connection 60D to the branch 60B side exceeds a predetermined amount. The excess flow valve 65 is a well-known valve conventionally used in the valve device 60.

[0052]

[0029] The operation of the valve device 60 when hydrogen is supplied from the tank 20 to the fuel cell 10 will be explained using Figures 1 and 2. By controlling the control valve 67, which is a solenoid valve, to open, the hydrogen in the tank 20 passes through the supply-side tank connection part 60D, the excess flow prevention valve 65, the supply-side check valve 68, the control valve 67, the external connection part 60A, the piping 70, and the piping 72 in that order, and is supplied to the auxiliary equipment 40. The pressure of the hydrogen supplied to the auxiliary equipment 40 is adjusted by the pressure reducing valve and injector provided in the auxiliary equipment 40, and the required amount is supplied to the fuel cell 10. For example, if the control valve 67, the pressure reducing valve, or the injector malfunctions and causes the flow rate to exceed a predetermined amount, the excess flow prevention valve 65 acts to limit the flow rate of hydrogen. Furthermore, a check valve is provided to prevent hydrogen from flowing from branch 70A toward receptacle 73, so hydrogen will not flow out of receptacle 73 when hydrogen is supplied to fuel cell 10.

[0053]

[0030] The operation of the valve device 60 when hydrogen is filled into the tank 20 from a hydrogen filling device (not shown) at a hydrogen station will be explained using Figures 1 and 2. When the nozzle (not shown) of the hydrogen filling device is fitted into the receptacle 73, the hydrogen inside the hydrogen filling device passes through the piping 71, piping 70, external connection part 60A, filling side check valve 90, and filling side tank connection part 60C in that order, and is filled into the tank 20. At this time, the valve spring of the filling side check valve 90 is set so that the pressure of the hydrogen flowing in from the receptacle 73 opens the filling side check valve 90.

[0054]

[0031] Figure 3 is a schematic diagram showing a filling-side check valve 90 according to the present invention. The filling-side check valve 90 is provided in a filling passage 61 formed in a housing 81 of a valve device 60. The filling-side check valve 90 includes a valve element 84, a valve seat 82, and a valve spring 80.

[0055]

[0032] The housing 81 is made up of multiple members. The housing 81 includes a first housing 81a and a second housing 81b. The first housing 81a has a first passage 61a that forms part of the filling passage 61. The second housing 81b has a second passage 61b that forms part of the filling passage 61. As shown in FIG. 3, the first passage 61a and the second passage 61b are formed coaxially. In this embodiment, the first passage 61a and the second passage 61b have the same inner diameter.

[0056]

[0033] When hydrogen is being filled into the tank 20, the hydrogen that flows into the valve device 60 from the external connection part 60A reaches the first passage 61a, and the pressure of the hydrogen opens the filling-side check valve 90. When the filling-side check valve 90 opens, the hydrogen in the first passage 61a passes through the filling-side check valve 90 and the second passage 61b and flows into the tank 20 from the filling-side tank connection part 60C. In the following explanation, the first passage 61a side, in other words, the lower side of the paper in Figure 3, may be referred to as the upstream side, and the second passage 61b side, in other words, the upper side of the paper, may be referred to as the downstream side.

[0057]

[0034] A valve seat 82 is formed at the end of the first passage 61a on the second housing 81b side, on which the seat portion of the valve body 84 sits when the filling side check valve 90 is closed.

[0058]

[0035] A valve chamber 83, which is a stepped cylindrical space, is formed coaxially with the second passage 61b at the end of the second passage 61b on the first housing 81a side. The valve chamber 83 accommodates a valve element 84. The valve chamber 83 has, from the upstream side, a first valve chamber 83a, a second valve chamber 83b having a larger diameter than the first valve chamber 83a, and a third valve chamber 83c having a smaller diameter than the first valve chamber 83a and a larger diameter than the second passage 61b.

[0059]

[0036] A sealing member (not shown) is disposed between the first housing 81 a and the second housing 81 b to prevent hydrogen from leaking to the outside. Therefore, when the filling-side check valve 90 is open, the first passage 61 a and the second passage 61 b ​​are airtightly connected.

[0060]

[0037] The valve element 84 of the filling side check valve 90 will be described with reference to Figs. 4 to 6. Fig. 4 is a front view of the valve element 84. Fig. 5 is a side view of the valve element 84 shown in Fig. 4, seen from the direction indicated by E. Fig. 6 is a cross-sectional view taken along line F-F in Fig. 4.

[0061]

[0038] As shown in Fig. 5, the valve element 84 includes a main body portion 84c, a valve portion 84a that seats on the valve seat 82 when the filling side check valve 90 is closed, and a large diameter portion 84b formed between the main body portion 84c and the valve portion 84a. The large diameter portion 84b is formed to have a larger diameter than the main body portion 84c and the valve portion 84a.

[0062]

[0039] The valve portion 84a has a seat portion 85 formed so that its diameter becomes smaller as it goes toward the opposite side from the large diameter portion 84. When the filling side check valve 90 is closed, the seat portion 85 abuts against the valve seat 82. The valve portion 84a has a protrusion 86 that protrudes toward the opposite side from the large diameter portion 84b as seen from the seat portion 85. The protrusion 86 is formed in a cylindrical shape. The protrusion 86 is formed contiguous with the seat portion 85.

[0063]

[0040] An inclined portion 87 is formed on the outer periphery of the large diameter portion 84b. The inclined portion 87 is formed in a shape such that the outer periphery of the large diameter portion 84b is cut away. The inclined portion 87 is formed so as to approach the central axis of the valve body 84 as it approaches the valve portion 84a. In this embodiment, three inclined portions 87 are formed at intervals of 120 degrees when viewed in the axial direction, but the number is not limited to three. Also, in FIG. 5, the inclined portion 87 is formed as a flat surface, but it does not have to be a flat surface.

[0064]

[0041] As shown in FIG. 6, the main body 84c has an axial passage 88 and a radial passage 89, which are passages through which hydrogen passes when the filling-side check valve 90 is open.

[0065]

[0042] The axial passage 88 is formed as an axial hole including the central axis of the main body portion 84c. The axial passage 88 is drilled in the axial direction from an end portion 84d of the main body portion 84c opposite to the large diameter portion 84b. In this embodiment, the axial passage 88 is drilled from the end portion 84d of the main body portion 84c to near the large diameter portion 84b.

[0066]

[0043] The radial passages 89 are drilled as radial holes that communicate between the axial passage 88 and the outer peripheral surface of the main body portion 84c. In this embodiment, four radial passages 89 are formed at 90-degree intervals, but the number of radial passages 89 is not limited to four. Also, in this embodiment, the radial passages 89 are formed near the large diameter portion 84b, but the position of the radial passages 89 is not limited to near the large diameter portion 84b. The radial passages 89 only need to be located in a position that opens into the second valve chamber 83b formed in the second housing 81b when the valve disc 84 is disposed in the housing 81.

[0067]

[0044] As shown in Fig. 3, the valve element 84 is accommodated in the valve chamber 83 with the valve portion 84a on the upstream side. A valve spring 80 is disposed between the downstream end face 84f of the large diameter portion 84b of the valve element 84 and the downstream end face 83d of the second valve chamber 83b. The valve spring 80 presses the valve element 84 in the valve closing direction with a predetermined set force. In addition, the inner peripheral surface 83f of the first valve chamber 83a guides the large diameter portion 84b of the valve element 84 when the filling side check valve 90 is opened and closed.

[0068]

[0045] When the filling side check valve 90 is closed, the position of the valve element 84 within the housing 81 is as follows. The large diameter portion 84b of the valve element 84 is located within the first valve chamber 83a. At this time, the downstream end face 84f of the large diameter portion 84b is located near the boundary between the first valve chamber 83a and the second valve chamber 83b. Furthermore, approximately half of the upstream area of ​​the main body portion 84c is located within the second valve chamber 83b, and approximately half of the downstream area is located within the third valve chamber 83c. Furthermore, the protrusion 86 is located within the first passage 61a.

[0069]

[0046] When the filling side check valve 90 is closed, the valve element 84 is pressed in the closing direction by the set force of the valve spring 80 and the hydrogen pressure on the second passage 61b side. On the other hand, when hydrogen is filled into the tank device 21 at a hydrogen station, the hydrogen pressure in the first passage 61a increases, pressing the valve element 84 in the opening direction. When the pressing force in the opening direction exceeds the pressing force in the closing direction, the filling side check valve 90 opens.

[0070]

[0047] Figure 7 shows the state immediately after the filling-side check valve 90 opens. After the filling-side check valve 90 opens, in the region where the stroke of the valve element 84 is relatively small, the gap between the protrusion 86 of the valve element 84 and the inner surface 61c of the first passage 61a functions as a throttle. This gap is called the upstream throttle portion 9!.

[0071]

[0048] At this time, the gap between the inclined portion 87 formed on the large diameter portion 84b of the valve body 84 and the inner circumferential surface 83f of the first valve chamber 83a also functions as a throttle. This gap is called the downstream throttle portion 92.

[0072] In the filling side check valve 90 according to the present invention, after the valve is opened, the upstream throttle portion 91 functions in a region where the stroke of the valve element 84 is relatively small, so that the hydrogen pressure in the first passage 61 a does not drop suddenly immediately after the valve is opened. This prevents the filling side check valve 90 from repeatedly opening and closing after opening, which is known as chattering.

[0073]

[0050] In the filling side check valve 90 according to the present invention, the dimensions of each part are set so that the opening area of ​​the downstream side throttle section 92 is smaller than the opening area of ​​the upstream side throttle section 91. Due to this relationship, after the filling side check valve 90 opens, the pressure in the first valve chamber 83 a increases, so the pressure drop in the first passage 61 a becomes even more gradual, which is more advantageous in avoiding chattering.

[0074]

[0051] In the filling-side check valve 90 according to the present invention, the downstream-side throttle portion 92 continues to function even after the stroke of the valve element 84 increases and the state in which the upstream-side throttle portion 91 functions ends, in other words, even after the protrusion 86 has come out of the first passage 61a. At this time, since the inclined portion 87 of the valve element 84 is formed to approach the central axis of the valve element 84 as it approaches the valve portion 84a, the opening area of ​​the downstream-side throttle portion 92 increases as the stroke of the valve element 84 increases, and the throttle characteristic becomes gentler. This characteristic further moderates the increase in hydrogen pressure in the first valve chamber 83a, which is more advantageous in avoiding chattering.

[0075]

[0052] Fig. 8 is a diagram showing a conventional filling side check valve 900 as a comparative example. The configuration of the conventional filling side check valve 900 will be described below with reference to Fig. 8. In describing the conventional filling side check valve 900, differences from the filling side check valve 900 according to the present invention will be mainly described, and descriptions of the same parts as the filling side check valve 900 according to the present invention will be omitted.

[0076]

[0053] In the conventional filling side check valve 900, when the valve is closed, the valve element 840 is pressed in the closing direction by the set force of the valve spring 80 and the hydrogen pressure on the second passage 61b side. On the other hand, when hydrogen is filled into the tank device 21 at a hydrogen station, the hydrogen pressure in the first passage 61a rises and presses the valve element 840 in the opening direction. When the pressing force in the opening direction exceeds the pressing force in the closing direction, the filling side check valve 900 opens.

[0077]

[0054] In the valve body 840 of the conventional filling side check valve 900, a protrusion 86 is not formed on the valve portion 840a, and a sloped portion 87 is not formed on the large diameter portion 840b. Furthermore, in the housing 810, the inner diameter portion of the valve chamber 830 formed by the first housing 810a and the second housing 810b is formed so as to have a larger gap between it and the outer diameter portion of the large diameter portion 840 of the valve body 840 compared to the present invention. In other words, the conventional filling side check valve 900 does not have an upstream-side throttle portion 91 or a downstream-side throttle portion 92 when the valve is open.

[0078]

[0055] Therefore, in the conventional filling side check valve 900, after the valve is opened, hydrogen in the first passage 61a rapidly flows into the valve chamber 830, causing the pressure in the first passage 61a to drop rapidly. At this time, the difference in hydrogen pressure between the first passage 61a and the valve chamber 830 rapidly decreases, causing the loading of the valve spring 80 to close the filling side check valve 900, which had opened once. When the filling side check valve 900 closes, the hydrogen pressure upstream of the valve element 840 rises again, causing the filling side check valve 900 to open again. This makes chattering more likely to occur in the conventional filling side check valve 900.

[0079]

[0056] Below, the behavior of the conventional filling side check valve 900 when it is opened and the behavior of the filling side check valve 90 of the present invention when it is opened will be explained in more detail.

[0080]

[0057] First, we will explain the behavior of the conventional filling-side check valve 900 when it is opened. In the conventional filling-side check valve 900, when hydrogen is supplied from the receptacle 73 side, the pressure of the hydrogen in the first passage 61a causes the valve element 840 to separate from the valve seat 82.

[0081]

[0058] At this time, if the seat diameter formed by the valve disc 840 and the valve seat 82 is Aph, the hydrogen pressure in the first passage 61a is Ph, and the hydrogen pressure in the valve chamber 83〇 is P1, the filling side check valve 9〇〇 opens when the value obtained by multiplying the difference between Ph and P1 by Aph exceeds the set force Fs of the valve spring 8〇.

[0082] [ 0 0 5 9 ] In other words, when ( P h — P l ) x A ph > F s , the filling side check valve 9 0 0 opens.

[0083] 〇

[0084]

[0060] Because the filling-side check valve 900 does not have an upstream throttle section 91 or a downstream throttle section 92, the pressure in the first passage 61a drops rapidly after the filling-side check valve 900 opens. In other words, the difference between P h and P 1 drops rapidly. As a result, the value obtained by multiplying the difference between P h and P 1 by A ph falls below the set force F s of the valve spring 8 0, and the filling-side check valve 900 closes.

[0085]

[0061] In other words, (Ph - Pl) x Aph < Fs, and the filling side check valve 900 closes.

[0086]

[0062] Figure 9 is a diagram illustrating the behavior of the pressure P h in the first passage 61a when chattering occurs in the conventional filling side check valve 900. In Figure 9, the horizontal axis represents time, the vertical axis represents the pressure P h in the first passage 61a, and time O represents the time when hydrogen supply from the receptacle 73 begins. The solid line in Figure 9 shows the behavior of the pressure P h in the first passage 61a when chattering occurs in the conventional filling side check valve 900. Furthermore, P1 in Figure 9 represents the hydrogen pressure in the receptacle 73.

[0087]

[0063] When hydrogen begins to be supplied from the receptacle 73, the pressure Ph in the first passage 61a rises. At time t1, the pressure Ph in the first passage 61a reaches P0, causing the conventional charging side check valve 900 to open. After the conventional charging side check valve 900 opens at time t1, the pressure Ph in the first passage 61a rapidly drops for the reasons described above. Then, at time t2, the pressure Ph in the first passage 61a reaches Pc, causing the conventional charging side check valve 900 to close. When the charging side check valve 900 closes at time t2, the pressure in the first passage 61a rises again. Then, at time t3, the filling side check valve 900 opens again. In this way, conventional filling side check valves 900 can sometimes cause chattering, in which the valve opens and closes repeatedly.

[0088] Next, the behavior of the filling side check valve 90 according to the present invention when it is open will be described. In the filling side check valve 90 according to the present invention, as in the conventional filling side check valve 900, when hydrogen is supplied from the receptacle 73 side, the pressure of the hydrogen in the first passage 61 a causes the valve element 84 to separate from the valve seat 82.

[0089]

[0065] At this time, if the area of ​​the seat formed by the valve disc 84 and the valve seat 82 is Aph, the hydrogen pressure in the first passage 61a is Ph, and the hydrogen pressure in the first valve chamber 83a is P1, the filling side check valve 90 opens when the difference between Ph and P1 multiplied by Aph exceeds the set force Fs of the valve spring 80 (see Figure 7).

[0090]

[0066] In other words, when (Ph - Pl) x Aph > Fs, the filling side check valve 90 opens.

[0091]

[0067] In the filling side check valve 90 according to the present invention, the upstream throttling section 91 and the downstream throttling section 92 function after the valve is opened, so that a rapid drop in pressure in the first passage 61a does not occur, as compared to the conventional filling side check valve 900.

[0092]

[0068] Therefore, after the valve is opened, the difference between the hydrogen pressure Ph in the first passage 61a and the hydrogen pressure P1 in the valve chamber 83 is prevented from becoming small rapidly, and the valve does not close immediately after opening.

[0093] Furthermore, as the stroke of the valve disc 84 increases and the downstream throttle section 92 continues to function even after the upstream throttle section 91 ceases to function, the pressure in the first valve chamber 83a becomes the pressure Ph in the first passage 61a. Therefore, the closing condition of the filling side check valve 90 at this time is (Ph - Pl) x Apc < Fs, because the pressure in the second valve chamber 83b is P1. Here, Apc is the axial projected area of ​​the large diameter section 84 of the valve disc 84, in other words, the axial projected area of ​​the downstream end face 84f of the large diameter section 84b.

[0094]

[0070] Comparing the closing condition of the conventional filling side check valve 9〇〇, (Ph - Pl) x Aph < Fs, with the closing condition of the filling side check valve 90 of the present invention, (Ph - Pl) x Apc < Fs, it is found that Aph < Apc, and therefore it is clear that the filling side check valve 9〇 of the present invention is more difficult to close when the difference between Ph and Pl becomes small.

[0095]

[0071] Figure 10 is a diagram for explaining the behavior of the pressure P h in the first passage 61 a in the filling side check valve 90 according to the present invention. In Figure 10, the horizontal axis represents time, the vertical axis represents the pressure P h in the first passage 61 a, and time O represents the point in time when hydrogen supply from the receptacle 73 begins. The solid line in Figure 10 shows the behavior of the pressure P h in the first passage 61 a in the filling side check valve 90 according to the present invention.

[0096]

[0072] When the supply of hydrogen from the receptacle 73 begins, the pressure Ph in the first passage 61a increases. Then, at time t1, the pressure Ph in the first passage 61a reaches P0, and the filling-side check valve 90 opens.

[0097]

[0073] After the charging side check valve 90 opens, hydrogen in the first passage 61a flows into the first valve chamber 83a, slowing the rate of increase in the pressure Ph in the first passage 61a. However, in the charging side check valve 90 according to the present invention, the pressure Ph in the first passage 61a does not decrease and continues to rise slowly due to the effects of the upstream throttle section 91 and the downstream throttle section 92. Thereafter, the pressure in the first passage 61a reaches the hydrogen pressure Pi in the receptacle 73.

[0098]

[0074] Therefore, in the filling side check valve 90 according to the present invention, the pressure in the first passage 61a does not decrease after the valve is opened, and therefore chattering does not occur.

[0099]

[0075] As explained above, the filling side check valve 90 according to the present invention prevents chattering when hydrogen is filled into the tank device 21 at a hydrogen station.

[0100] [Explanation of symbols]

[0101] [ 0 0 7 6 ]

[0102] 2 〇: Tank, 2 1: Tank device, 6 〇: Valve device, 6 1: Filling passage, 8 〇: Valve spring, 8 1: Housing, 8 2: Valve seat, 8 4: Valve body, 8 4 a: Valve section, 8 4 b: Large diameter section, 8 4 c: Main body, 8 5: Seat section, 8 6: Projection section, 8 7: Inclined section, 9 〇: Check valve, 9 1: Upstream throttle section, 9 2: Downstream throttle section

Claims

[Document name] Scope of claims

1. A check valve (90) used in a valve device (60) attached to a tank (20) for storing hydrogen, the check valve (90) being disposed in a filling passage (61) formed in a housing (81) of the valve device (60) and through which the hydrogen to be filled into the tank (20) passes, the check valve (90) comprising a valve body (84) and a valve seat (85) formed in the housing (81). and a valve spring (8 ◯) that presses the valve body (84) against the valve seat (82). The valve body (84) includes a main body portion (84c) and a valve portion (84d) that seats on the valve seat (82) when the valve is closed. and a large diameter portion (84b) formed between the main body portion (84c) and the valve portion (84a) and having an outer diameter larger than that of the main body portion (84c), wherein the valve portion (84a) has a projection portion (86) which is a projection that projects toward the upstream side of the filling passage (61) further than a seat portion (85) that abuts against the valve seat (82) when the check valve (90) is closed, and the check valve (90) forms an upstream throttle portion (91) between the projection portion (86) and the filling passage (61) when the check valve (90) is open.

2. The check valve (90) according to claim 1, wherein the large diameter portion (84b) is provided, on its outer periphery, with a plurality of inclined portions (87) that are inclined toward a central axis of the valve body (84) as the large diameter portion (84b) approaches the valve portion (84a), and the check valve (90) forms a downstream throttle portion (92) between the large diameter portion (84b) and the filling passage (61) when the check valve (90) is open.

3. A check valve (90) as claimed in claim 2, wherein an opening area of ​​the downstream throttle portion (92) is smaller than an opening area of ​​the upstream throttle portion (91).

4. A valve device (60) comprising a check valve (90) according to any one of claims 1 to 3.

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