Hydrogen consumption device and hydrogen consumption system

Abstract

This hydrogen consumption device comprises hydrogen consumption equipment to which a detachable hydrogen tank is connected and which consumes hydrogen in the hydrogen tank. An oxygen concentration reduction mechanism for reducing the concentration of oxygen mixed in hydrogen and supplying said hydrogen to the hydrogen consumption equipment is disposed in hydrogen supply piping between the hydrogen tank and the hydrogen consumption equipment.

Description

Hydrogen consumption device, hydrogen consumption system

[0001] The present disclosure relates to devices that consume hydrogen as a supplied fuel.

[0002] Patent Document 1 discloses a hydrogen tank that includes a cylindrical hydrogen tank body that is detachably mounted on a vehicle (gas consuming device) and a handle formed on one longitudinal end of the hydrogen tank body. Patent Document 1 also shows that by attaching the hydrogen tank body to the gas consuming device, hydrogen is supplied to a fuel cell in the gas consuming device via piping within the gas consuming device.

[0003] Japanese Patent Application Laid-Open No. 2023-056952

[0004] In devices where a hydrogen tank can be detachably attached to a hydrogen consumption device, the detachable portion of the hydrogen tank and the detachable portion of the hydrogen consumption device are exposed to air, especially when the hydrogen tank is not installed. When attaching the hydrogen tank to the hydrogen consumption device, air can get trapped between the detachable portion of the hydrogen tank and the detachable portion of the hydrogen consumption device. When a hydrogen consumption device is equipped with a fuel cell (hydrogen consumption device) and the hydrogen tank is attached and the hydrogen consumption device is started, the air gets trapped in the hydrogen supply pipe that supplies hydrogen from the hydrogen tank to the hydrogen consumption device and is then supplied to the fuel cell. If a certain amount of air gets trapped in the anode side (hydrogen supply side) of the fuel cell, a region of high air density occurs on the anode side of the fuel cell. In this region of high air density, an abnormal potential higher than the normal reaction potential may occur in part of the cell; the carbon support used in the catalyst may be oxidized by oxygen in the air, reducing catalytic performance; or a reaction (combustion) may occur between hydrogen and oxygen contained in the air on the anode side, causing sintering due to the reaction heat, resulting in catalyst degradation. These problems are even more pronounced in hydrogen consumption devices equipped with detachable hydrogen tanks, where air contamination occurs every time the tank is attached or detached. Furthermore, when the hydrogen consumption device is equipped with a hydrogen engine (hydrogen consumption equipment), oxygen contamination in the hydrogen supply pipe that supplies hydrogen to the hydrogen engine causes the ratio of hydrogen injected into the hydrogen engine's cylinders to oxygen supplied to the combustion chamber from the intake pipe to be lean relative to the target air-fuel ratio. Operating the hydrogen engine lean during startup can cause rotational fluctuations and poor startability, such as a longer startup time.

[0005] In view of the above problems, the present disclosure aims to provide a hydrogen consuming device with a detachable hydrogen tank that can suppress the intrusion of oxygen and thereby suppress deterioration of the hydrogen consuming device and deterioration of its output (power generation amount and rotational output). Also, a hydrogen consuming system including the hydrogen consuming device is provided.

[0006] The present application discloses a hydrogen consumption device that includes a hydrogen consumption device that is connected to a detachable hydrogen tank and consumes hydrogen from the hydrogen tank, and in which an oxygen concentration reduction mechanism is disposed in the hydrogen supply piping from when the hydrogen leaves the hydrogen tank to when the hydrogen consumption device is consumed, for reducing the concentration of oxygen mixed in the hydrogen and supplying hydrogen to the hydrogen consumption device.

[0007] The oxygen concentration reducing mechanism may be disposed in a hydrogen supply pipe through which hydrogen flows from a hydrogen tank to a hydrogen consuming device, and may be an oxygen treatment member that reduces the oxygen concentration downstream of the oxygen concentration reducing mechanism compared to the oxygen concentration upstream thereof.

[0008] The oxygen treatment member is provided in the hydrogen supply pipe and may include a hydrogen separation membrane that allows hydrogen to permeate but not oxygen, or a catalyst that reacts hydrogen and oxygen to convert them into water.

[0009] The oxygen reduction mechanism may be a release pipe that releases the fluid in the hydrogen supply pipe to the atmosphere.

[0010] The oxygen concentration reduction mechanism is arranged in a bypass branched off from the hydrogen supply pipe, and is equipped with an oxygen treatment member that reduces the oxygen concentration downstream of the oxygen concentration reduction mechanism compared to its upstream side, a switching valve that switches the flow path between the hydrogen supply pipe and the bypass, and a control device that controls the switching valve, and the control device may be configured to control the switching valve so that hydrogen flows through the bypass when it is determined that the oxygen concentration is below a predetermined value after the hydrogen tank is installed.

[0011] The determination can be made by allowing hydrogen to flow through the bypass for a predetermined time after the hydrogen tank is attached to the hydrogen consuming device.

[0012] The determination can be made by detecting a decrease in oxygen concentration using an oxygen concentration sensor after the hydrogen tank is attached to the hydrogen consumption device.

[0013] The oxygen concentration reduction mechanism is arranged in a bypass branching off from the hydrogen supply pipe through which hydrogen flows from the hydrogen tank to the hydrogen consuming device, and is equipped with an oxygen treatment member that reduces the oxygen concentration downstream of the oxygen concentration reduction mechanism compared to its upstream side, a switching valve that switches the flow path between the hydrogen supply pipe and the bypass, and a control device that controls the switching valve, and the control device can be configured to operate the switching valve so that hydrogen flows into the bypass when the residual pressure in the hydrogen tank is below a predetermined pressure.

[0014] The present application discloses a hydrogen consumption system comprising a hydrogen tank and the above-described hydrogen consumption device.

[0015] According to the present disclosure, in a hydrogen consumption device equipped with a removable hydrogen tank, it is possible to prevent mixed air (oxygen) from reaching the hydrogen consumption equipment, thereby preventing deterioration of the hydrogen consumption equipment and a decrease in output (power generation amount and rotational output) due to air (oxygen) mixing in.

[0016] FIG. 1 is a diagram showing the configuration of a hydrogen consumption system 10 (an example in which a fuel cell 40 is provided as the hydrogen consumption device). FIG. 2 is a diagram showing the configuration of a hydrogen consumption system 10 (an example in which a hydrogen engine 41 is provided as the hydrogen consumption device). FIG. 3 is an external view showing the configuration of a hydrogen tank 11. FIG. 4 is a cross-sectional view showing the configuration of the hydrogen tank 11. FIG. 5 is a diagram for explaining the on-off valve 15 and the connection section 30. FIG. 6 is a cross-sectional view showing the storage section 21. FIG. 7 is a diagram for explaining the storage section 21. FIG. 8 is a diagram for explaining the control device 50. FIG. 9 is a diagram for explaining the connection position. FIG. 10 is a diagram for explaining the flow of hydrogen tank connection control S10. FIG. 11 is a diagram for explaining hydrogen tank connection control S10. FIG. 12 is a diagram for explaining hydrogen tank connection control S10. FIG. 13 is a diagram for explaining hydrogen tank connection control S10. FIG. 14 is a diagram for explaining hydrogen tank connection control S10. FIG. 15 is a diagram for explaining hydrogen tank connection control S10. FIG. 16 is a diagram for explaining hydrogen tank connection control S10. FIG. 17 is a diagram for explaining hydrogen tank connection control S10. Figure 18 is a diagram showing the configuration of hydrogen consuming system 10a. Figure 19 is a diagram showing the configuration of hydrogen consuming system 10a'. Figure 20 is a diagram showing the configuration of hydrogen consuming system 10b. Figure 21 is a diagram explaining the flow of control S20 for reducing oxygen concentration. Figure 22 is a diagram showing the configuration of hydrogen consuming system 10c. Figure 23 is a diagram explaining the flow of control S30 for reducing oxygen concentration. Figure 24 is a diagram showing the configuration of hydrogen consuming system 10d. Figure 25 is a diagram explaining the flow of control S40 for reducing oxygen concentration.

[0017] 1. Basic Form of Hydrogen Consumption System (Hydrogen Consumption System 10) First, we will explain the hydrogen consumption device 20 and hydrogen consumption system 10, which are basic forms of hydrogen consumption devices and hydrogen consumption systems common to the hydrogen consumption devices and hydrogen consumption system examples according to the present disclosure described later. Figures 1 and 2 conceptually show the configuration of the hydrogen consumption system 10. This hydrogen consumption system 10 includes a hydrogen tank 11, which is a hydrogen supply source, and a hydrogen consumption device 20, which is a destination of the hydrogen supply. The hydrogen consumption system 10 shown in Figure 1 generates electricity by supplying hydrogen stored in the hydrogen tank 11 to a fuel cell 40, which serves as a hydrogen consumption device included in the hydrogen consumption device 20. The hydrogen consumption system 10 shown in Figure 2 supplies hydrogen stored in the hydrogen tank 11 to a hydrogen engine 41, which serves as a hydrogen consumption device included in the hydrogen consumption system 20. Here, in this form of hydrogen consumption system 10, the hydrogen tank 11 is configured to be detachable from the hydrogen consumption device 20.

[0018] By equipping such a hydrogen consumption system 10 with the oxygen concentration reduction mechanism of each form described below, it is possible to obtain the various forms of the present disclosure, namely, hydrogen consumption device 20a, hydrogen consumption system 10a (form 1), hydrogen consumption device 20b, hydrogen consumption system 10b (form 2), hydrogen consumption device 20c, hydrogen consumption system 10c (form 3). Each form and its variations will be described later.

[0019] One hydrogen consumption system of the present disclosure, as shown in FIG. 1, is a system that includes a fuel cell (hydrogen consumption device) that generates electricity using hydrogen supplied from a removable hydrogen tank as fuel, and that provides this electricity for use. Specific examples include an electric vehicle, a generator, and an electricity supply source for a building. Another hydrogen consumption system of the present disclosure, as shown in FIG. 2, is a system that includes a hydrogen engine (hydrogen consumption device) that runs on hydrogen supplied from a removable hydrogen tank as fuel, and that provides the driving force of this hydrogen engine for use. Specific examples include applications such as powering an automobile or driving a generator. The examples of FIG. 1 and FIG. 2 are the same except for the fuel cell 40 and the hydrogen engine 41. This will be explained in detail below.

[0020] 1.1 Hydrogen Tank The hydrogen tank 11 is a container for storing the fuel to be supplied (hydrogen in this embodiment) in a liquid or gas state. Explained in Figures 3 and 4, Figure 3 is an external view, and Figure 4 is a cross-sectional view of the tank 11 taken along the axis O. As can be seen from these figures, in this embodiment the hydrogen tank 11 has a liner 12, a reinforcing layer 13, a mouthpiece 14, and an on-off valve 15. Each component is described below.

[0021] 1.1.1. Liner The liner 12 is a hollow member that defines the interior space of the hydrogen tank 11 and is cylindrical in this embodiment. The liner 12 has a body portion 12a with a generally constant diameter, with openings at both ends narrowed by dome-shaped side ends 12b, and a nozzle 14 is disposed at the narrowed opening 12c. The liner 12 may be made of any material capable of retaining the contents (e.g., hydrogen) contained in the interior space without leaking, and any known material may be used. Specific examples include nylon resin, polyethylene-based synthetic resin, and metals such as stainless steel and aluminum. Among these, synthetic resin is preferred as the material for the liner in terms of reducing the tank's weight. The thickness of the liner 12 is not particularly limited, but is preferably 0.5 mm to 3.0 mm.

[0022] 1.1.2 Reinforcement Layer The reinforcing layer 13 is made of multiple layers of laminated fibers impregnated with hardened resin. The fiber layer is formed by wrapping multiple layers of fiber bundles around the outer periphery of the liner 12 to a predetermined thickness. The thickness of the reinforcing layer 13 and the number of turns of the fiber bundles are determined by the required strength and are not particularly limited, but are generally around 10 mm to 30 mm.

[0023] <Fiber bundles> The fiber bundles of the reinforcing layer 13 are made of, for example, carbon fibers, and the fiber bundles are band-shaped bundles of carbon fibers having a predetermined cross-sectional shape (for example, a rectangular cross-section). Specifically, the cross-sectional shape is not particularly limited, but an example would be a rectangle with a width of about 6 mm to 20 mm and a thickness of about 0.1 mm to 0.3 mm. The amount of carbon fibers contained in the fiber bundle is also not particularly limited, but an example would be about 36,000 carbon fibers.

[0024] <Impregnated Resin> The resin impregnated and cured into the fibers (fiber bundles) in the reinforcing layer 13 is not particularly limited as long as it can increase the strength of the fibers. Examples of such resins include thermosetting resins that are cured by heat, such as epoxy resins and unsaturated polyester resins that contain an amine- or anhydride-based curing accelerator and a rubber-based toughening agent. Other examples include resin compositions that use an epoxy resin as the base agent and are cured by mixing a curing agent into the resin composition. In this case, the resin composition, which is a mixture of the base agent and the curing agent, reaches and penetrates the fiber layer between the time of mixing and the time of curing, and automatically hardens.

[0025] <Protective Layer> If necessary, a protective layer may be disposed around the outer periphery of the reinforcing layer. When provided, for example, a glass fiber is wound around the protective layer and impregnated with resin. The impregnated resin can be considered the same as the reinforcing layer 12. This makes it possible to impart impact resistance to the hydrogen tank 11. There are no particular limitations on the thickness of the protective layer, but it can be approximately 1.0 mm to 1.5 mm.

[0026] 1.1.3. Mouthpieces The mouthpieces 14 are components attached to each of the two openings 12c of the liner 12. They are located at both ends of the liner 12 in the direction of the axis O and function as openings that communicate between the inside and outside of the hydrogen tank 11. An on-off valve 15 is attached to one of the mouthpieces. Therefore, the mouthpiece 14 has a hole with a circular cross section in which the on-off valve 15 is disposed. The inner surface of the hole is provided with a female thread that corresponds to the male thread of the on-off valve 15. The on-off valve 15 is fixed to the mouthpiece 14 by mating the male thread of the on-off valve 15 with this female thread. In addition, the inner surface of the hole has a smooth sealing surface on the tank inner side (high-pressure side) of the female thread. A seal member attached to the outer periphery of the on-off valve 15 comes into contact with this sealing surface to seal the inside of the hydrogen tank 11.

[0027] The material constituting the nozzle 14 is not particularly limited as long as it has the necessary strength, but examples include stainless steel and aluminum.

[0028] 1.1.4. On-Off Valve The on-off valve 15 is held in a hole in the nozzle 14 so as to bridge the inside and outside of the hydrogen tank 11. The on-off valve 15 is disposed in one of the two nozzles 14 provided at both longitudinal ends of the hydrogen tank 11. A plug 14a is disposed and sealed in the other nozzle 14. Figure 5 is a view including the on-off valve 15 and its vicinity in Figure 4, showing the on-off valve 15 separated from a connection portion 42 of the hydrogen consumption device 20 (described below). The on-off valve 15 has a shaft portion disposed inside the hole in the nozzle 14, and the outer periphery of the shaft portion is provided with a male thread that mates with the female thread of the nozzle 14, thereby fixing the on-off valve 15 to the hole in the nozzle 14. A sealing member (not shown) is disposed on the outer periphery of the on-off valve 15, and this sealing member is disposed so as to contact the sealing surface on the inner surface of the hole in the nozzle 14, thereby achieving an airtight seal.

[0029] The on-off valve 15 has a valve body 16 and a connection portion 17 .

[0030] <Valve element> The valve element 16 is a switching valve that allows and restricts communication between the inside and outside of the hydrogen tank 11. In this embodiment, the valve element 16 is biased to restrict communication when closed, and pressing the valve element 16 against the biasing force moves the valve element 16 to allow communication. In this embodiment, communication is switched by pressing and releasing the pressure on the valve element 16, so a means for pressing the valve element 16 is required. For this reason, the hydrogen consumption device 20 is provided with a means (push rod 30a) for pressing the valve element 16, as described below.

[0031] <Connection Portion> The on-off valve 15 has a connection portion 17 that houses the valve body 16 and into which the push rod 30 a is inserted. Therefore, the connection portion 17 has an insertion hole 17 a through which the push rod 30 a is inserted and which communicates with the valve body 16.

[0032] 1.1.5. Other The allowable pressure of the hydrogen tank 11 is not particularly limited, but from the perspective of being able to supply a larger amount of hydrogen while being small enough to maintain portability, a tank that can store hydrogen at an allowable pressure of more than 20 MPa and not more than 70 MPa can be used.

[0033] The hydrogen consumption system 10 is provided with a plurality of hydrogen tanks 11 (for example, three), and each hydrogen tank 11 is filled with hydrogen. Here, an example is given in which three hydrogen tanks 11 are provided, and these are designated by the reference numerals 11a, 11b, and 11c to distinguish them. These hydrogen tanks 11 may all have the same capacity, or tanks of different capacities may be included.

[0034] In addition to the above, although not shown, the hydrogen tank 11 may be provided with an exterior body that forms the outer shell of the hydrogen tank 11, and a handle that can be grasped when attaching or detaching the hydrogen tank 11 to or from the hydrogen consumption device 20. This increases the convenience of the cartridge type (which can be detached from the hydrogen consumption device and carried around for filling with hydrogen).

[0035] 1.2 Hydrogen Consumption Device The hydrogen consumption device 20 is a device that receives and consumes hydrogen supplied from the hydrogen tank 11. As shown in Figure 1, the hydrogen consumption device 20 in this embodiment includes an attachment portion 21, a connection portion 30, a supply flow path 31, a first pressure gauge 32, a check valve 33, a second pressure gauge 34, a filter 35, a pressure reducing valve 36, a third pressure gauge 37, a filter 38, an injector 39, a hydrogen consumption device (a fuel cell 40 in the example of Figure 1, and a hydrogen engine 41 in the example of Figure 2), and a control device 50. Each part will be described below.

[0036] 1.2.1 Mounting Part The mounting part 21 is the part where the hydrogen tank 11 is stored when the hydrogen tank 11 is connected to the hydrogen consumption device 20. Figure 6 shows a schematic cross section of the mounting part 21 with the hydrogen tank 11 mounted thereon and the on-off valve 15 of the hydrogen tank 11 connected to the push rod 30a of the connection part 30. Figure 7 also shows a schematic of the components provided in and around the mounting part 21. As can be seen from Figures 6 and 7, the mounting part 21 includes a storage hole 22, a base 23, a lock pin 24, a stepping motor 25, and a sensor 26.

[0037] [Storage Hole] Storage hole 22 is a space in which hydrogen tank 11 is stored, has opening 22a through which hydrogen tank 11 can be inserted and removed, and is a space surrounded by inner wall 22b. Connection part 30 (push rod 30a) is disposed at bottom 22c of storage hole 22, on the opposite side of opening 22a. In this embodiment, storage holes 22 are provided in three vertical stages, but the number and arrangement of storage holes 22 are not particularly limited.

[0038] [Base] The base 23 is located inside and below the storage hole 22, and is a component on which the hydrogen tank 11 is placed and fixed on its upper surface. The base 23 is arranged to be movable in the depth direction of the storage hole 22 (the direction connecting the opening 22a and the bottom 22c, the direction in which the on-off valve 15 of the hydrogen tank 11 approaches and moves away from the connection part 30 (push rod 30a), the direction of arrow T in FIG. 7). The means for movement is not particularly limited, but examples include a combination of rails and wheels. The base 23 further has a first engagement recess 23a and a second engagement recess 23b on its underside (the surface facing the inner wall 22b). The first engagement recess 23a and the second engagement recess 23b may have any specific shape as long as they are configured to allow the lock pin 24 to be engaged and disengaged, and may be a depression or a groove (a groove extending into / out of the plane of FIG. 7).

[0039] The widths of the first engagement recess 23a and the second engagement recess 23b (the size in the direction in which the base 23 moves) are larger than the width of the lock pin 24. In other words, even when the lock pin 24 protrudes so as to enter the inside of the first engagement recess 23a and the second engagement recess 23b, the base 23 can move within the range of the widths of the first engagement recess 23a and the second engagement recess 23b. The first engagement recess 23a is on the side closer to the push rod 30a, and the second engagement recess 23b is on the opening 22a side, and they are arranged with a predetermined distance in the direction in which the base 23 moves. This distance is set to a size that allows for control, which will be described later.

[0040] [Lock Pin] The lock pin 24 is a pin arranged so as to be able to protrude and retract from the inner wall 22b, and when protruding, it enters the inside of the first engagement recess 23a and the second engagement recess 23b and can engage with the first engagement recess 23a and the second engagement recess 23b. On the other hand, the lock pin 24 is arranged so as not to engage with the first engagement recess 23a and the second engagement recess 23b when retracted. The lock pin 24 is electrically connected to the control device 50, and its protrusion and retraction are controlled based on signals from the control device 50.

[0041] [Stepping Motor] The stepping motor 25 is a power source that moves the base 23 via gears. The specific form of the stepping motor is not particularly limited, and known stepping motors can be used. The stepping motor 25 is electrically connected to the control device 50, and the rotation angle and rotation speed are controlled based on signals from the control device 50, thereby precisely controlling the movement of the base 23.

[0042] [Sensor] Sensor 26 detects the position of the hydrogen tank 11, in particular the position of the on-off valve 15 (position in the direction of movement of the base 23). The specific form of sensor 26 is not particularly limited and any known sensor can be used, but it may detect the position based on the rotation angle of the stepping motor 25, or it may optically detect the position of the on-off valve 15. Sensor 26 is electrically connected to control device 50 and is configured to be able to transmit the measured position of the hydrogen tank 11 to control device 50 as a signal.

[0043] 1.2.2 Connection Part Connection part 30 is located at the connection part with hydrogen tank 11, and connects to connection part 17 provided on opening / closing valve 15 of hydrogen tank 11, and operates the opening and closing of valve body 16 of hydrogen tank 11. As can be seen from Figure 5, connection part 30 has a push rod 30a.

[0044] The push rod 30a is a member that can press the valve element 16 provided on the on-off valve 15 of the hydrogen tank 11, and in this embodiment is rod-shaped and is capable of pressing the valve element 16 with its tip. Therefore, the push rod 30a is configured so that it can be inserted into an insertion hole 17a formed in the connection part 17 of the on-off valve 15. Furthermore, the push rod 30a is configured to form a flow path that allows hydrogen to flow from the inside of the hydrogen tank 11 to the hydrogen supply pipe 31 when the push rod 30a presses the valve element 16 to open the on-off valve 15.

[0045] 1.2.3 Hydrogen Supply Pipe The hydrogen supply pipe 31 constitutes a path that guides hydrogen from the hydrogen tank 11 to the hydrogen consumers 40, 41. The connection part 30 is disposed on the hydrogen tank 11 side of the hydrogen supply pipe 31. In this embodiment, the hydrogen tanks 11a, 11b, and 11c are connected to the hydrogen consumers 40, 41, respectively. Here, pipes 31a, 31b, and 31c extending from the connection parts 30 for the hydrogen tanks 11a, 11b, and 11c respectively join together to form a single pipe 31d, which is connected to the hydrogen consumers 40, 41.

[0046] The first pressure gauge 32 is provided in each of the hydrogen supply pipes 31 a, 31 b, and 31 c, and measures the pressure inside the flow path of each of the hydrogen supply pipes 31 a, 31 b, and 31 c (pressure inside the pipes), which corresponds to the internal pressure of each of the hydrogen tanks 11 a, 11 b, and 11 c. In this embodiment, the specific form of the first pressure gauge 32 is not particularly limited, but it is configured to be able to transmit the obtained pressure value data to the control device 50.

[0047] 1.2.5. Check valve A check valve 33 is provided on each of the hydrogen supply pipes 31a, 31b, 31c, and allows fluid to flow from each of the hydrogen tanks 11a, 11b, 11c toward the hydrogen consuming devices 40, 41, while restricting fluid flow in the opposite direction. This prevents fluid from flowing back into the hydrogen tanks 11a, 11b, 11c. The specific form of the check valve is not particularly limited, and any known check valve may be used.

[0048] The second pressure gauge 34 is provided in the hydrogen supply pipe 31d after the hydrogen supply pipes 31a, 31b, and 31c join, and measures the internal pressure of the hydrogen supply pipe 31d, which is still in a high-pressure state after the hydrogen supply pipes 31a, 31b, and 31c join and up to the pressure reducing valve 36. In this embodiment, the specific form of the second pressure gauge 34 is not particularly limited, but it is configured to be able to transmit the obtained pressure value data to the control device 50.

[0049] 1.2.7 Filter The filter 35 is placed before the fluid enters the pressure reducing valve 36 and removes foreign matter that has become mixed into the fluid. Examples of foreign matter that can be removed by the filter 35 include metal powder and pieces of sealing material that were originally mixed into the hydrogen tank 11 or that have been generated in the hydrogen consuming device 20. The specific form of the filter 35 is not particularly limited, and any known filter can be used.

[0050] 1.2.8. Pressure Reducing Valve The pressure reducing valve 36 is a known device that reduces the pressure in the upstream piping and supplies the pressure to the downstream piping. The specific form of the pressure reducing valve is not particularly limited and is known. The pressure reducing valve 36 reduces the pressure of hydrogen gas from a high pressure (e.g., 70 MPa) equivalent to that in the hydrogen tank 11 to a pressure (e.g., about 1 MPa) to be supplied to the fuel cell 40.

[0051] 1.2.9 Third Pressure Gauge The third pressure gauge 37 is located closer to the hydrogen consuming devices 40 and 41 than the pressure reducing valve 36, and is a pressure gauge that measures the internal pressure of the hydrogen supply pipe 31d after pressure reduction. This third pressure gauge 37 can be used to confirm whether the pressure inside the pipe is suitable for supplying hydrogen to the fuel cell 40. In this embodiment, the specific form of the third pressure gauge 37 is not particularly limited, but it is configured to be able to transmit the obtained pressure value data to the control device 50.

[0052] 1.2.10 Filter The filter 38 is disposed closer to the hydrogen consuming devices 40 and 41 than the third pressure gauge 37. The excluded substances and other aspects of the filter 38 can be considered to be similar to those of the filter 35 described above.

[0053] Injection 39 is disposed on the hydrogen supply pipe 31 (hydrogen supply pipe 31d in this embodiment) between connection 30 and hydrogen consumers 40, 41, closer to the hydrogen consumers 40, 41 than filter 38, and controls the supply of hydrogen to hydrogen consumers 40, 41. The specific form of injection is not particularly limited, but an example is a flow control valve.

[0054] 1.2.12. Hydrogen Consuming Device The hydrogen consuming device is a device that consumes supplied hydrogen, and receives a supply of hydrogen from the hydrogen tank 11. In the example of FIG. 1, a fuel cell 40 is provided as the hydrogen consuming device, and generates electricity by receiving a supply of air from an air hole (not shown). The specific configuration of the fuel cell 40 is not particularly limited, and a known fuel cell can be used. On the other hand, in the example of FIG. 2, a hydrogen engine 41 is provided as the hydrogen consuming device, and the engine is driven by the supplied hydrogen as fuel.

[0055] As will be described later, the control device 50 is a device that controls the connection of the hydrogen tank 11 to the connection part 30 (push rod 30a). Therefore, in this embodiment, the control device 50 is configured to be able to communicate with the lock pin 24, stepping motor 25, sensor 26, injector 39, and first to third pressure gauges (32, 34, 37).

[0056] 8, the control device 50 includes a CPU (Central Processing Unit) 51 which is a processor and performs calculations, a RAM (Random Access Memory) 52 which functions as a work area, a ROM (Read-Only Memory) 53 which functions as a recording medium, a receiving unit 54 which is an interface that receives information into the control device 50 whether wired or wireless, and a transmitting unit 55 which is an interface that sends information from the control device 50 to the outside whether wired or wireless. Therefore, the control device 50 is configured so that the sensor 26 and the first to third pressure gauges 32, 34, and 37 are connected to the receiving unit 54 to receive information, and so that the lock pin 24, stepping motor 25, and injector 39 are connected to the transmitting unit 55 to transmit signals to operate them.

[0057] The control device 50 stores a program that performs calculations for the hydrogen tank connection control S10 (described later) and transmits operation signals to each device. In the control device 50, the CPU 51, RAM 52, and ROM 53, which serve as hardware resources, work together with the program. Specifically, the CPU 51 executes the computer program stored in the ROM 53 in the RAM 52, which functions as a work area, thereby performing the desired control. Information acquired or generated by the CPU 51 is stored in the RAM 52. Alternatively, a separate recording medium may be provided inside or outside the control device 50, and the program and various data may be recorded thereon. Specific control content will be described later.

[0058] Such a control device 50 can typically be configured by a computer.

[0059] 1.3 Hydrogen Tank Connection Control The following describes the connection control of the hydrogen tank 11 in the hydrogen consumption device 20. Before that, the state before the connection control is started and the state after the connection control is completed will be described.

[0060] 1.3.1. Hydrogen Tank Disconnected State As described above, when the hydrogen tank 11 is placed in the mounting portion 21 of the hydrogen consumption device 20 and before it is connected to the connection portion 30 of the hydrogen consumption device 20, the push rod 30a and the on-off valve 15 are separated as shown in FIG. 5, and the on-off valve 15 is closed by the valve body 16 on the hydrogen tank 11.

[0061] 9, when the hydrogen tank 11 is placed in the mounting portion 21 of the hydrogen consumption device 20 and connected to the connection portion 30 of the hydrogen consumption device 20, the push rod 30a is inserted into the insertion hole 17a of the connection portion 17, and the valve body 16 is pressed. This allows hydrogen to flow from the inside of the hydrogen tank 11 to the hydrogen supply pipe 31 via the push rod 43a, and hydrogen can be supplied to the hydrogen consumption devices 40, 41. Note that hydrogen is supplied to the hydrogen consumption devices 40, 41 when the injector 39, which is electrically connected to the control device 50, operates in response to a command from the control device 50.

[0062] 1.3.3 Hydrogen Tank Connection Control Figure 10 shows the flow of hydrogen tank connection control S10 according to one embodiment. Figures 11 to 17 are diagrams for explaining hydrogen tank connection control S10. As can be seen from Figure 10, hydrogen tank connection control S10 comprises steps S11 to S18. Each step is explained below.

[0063] 11 , the base 23 is assumed to have moved away from the push rod 30a, with the lock pin 24 inserted into the first engagement recess 23a to restrict movement. The hydrogen tank 11 is then placed and fixed in a predetermined position on the base 23. There are no particular limitations on the fixing method, but examples include tightening with a band, or providing irregularities on the outer surface of the hydrogen tank 11 and corresponding irregularities on the surface of the base 23, and combining these irregularities.

[0064] [Step S11] In step S11, a command to start connecting the hydrogen tank 11 is input to the control device 50. The command to start the connection may be, for example, a command generated by a user operating a switch, or a signal sent to the control device 50 by a proximity sensor (not shown) indicating that the hydrogen tank 11 has been placed on the base 23.

[0065] [Step S12] In step S12, origin learning is performed. Specifically, as shown in FIG. 12 , the control device 50 operates the stepping motor 25 to move the base 23 to a position where the lock pin 24 contacts the wall of the first engagement recess 23a that is on the second engagement recess 23b side. The control device 50 then sets this position as the origin of the base 23. The detection of contact is not particularly limited and can be performed by known means. For example, contact can be determined by detecting a value of the sensor 26 indicating a contact position, or by detecting an increase in the torque value of the stepping motor 25 due to contact (in this case, a separate torque sensor (not shown) is disposed on the stepping motor 25 and the control device 50 is configured to receive the signal).

[0066] [Step S13] In step S13, the lock pin 24 is released. Specifically, in response to a command from the control device 50, the lock pin 24 is released from the first engagement recess 23a as shown in FIG.

[0067] [Step S14] In step S14, the base 23 is moved to the standby position. The standby position is a position where the on-off valve 15 of the hydrogen tank 11 is not yet connected to the push rod 30a, but is positioned near the push rod 30a. In step S14, the control device 50 activates the stepping motor 25 to move the base 23 closer to the push rod 30a. This movement positions the base 23 so that the lock pin 24 can be inserted into the second engagement recess 23b, as shown in FIG.

[0068] [Step S15] In step S15, it is determined whether the standby position obtained in step S14 is an abnormal position (within the normal position range). This determination is made by determining whether the position information obtained from the sensor 26 or the like is a predetermined position. If it is within the normal range, the answer is Yes and the process proceeds to step S16. If it is outside the normal range, the answer is No and an abnormality is reported (an abnormality display or sound is given) and the control is terminated.

[0069] [Step S16] In step S16, the lock pin 24 is inserted into the second engagement recess 23b. Specifically, in response to a command from the control device 50, the lock pin 24 protrudes toward the second engagement recess 23b and is positioned inside the second engagement recess 23b as shown in FIG.

[0070] [Step S17] In step S17, position correction is performed. Specifically, as shown in FIG. 16 , the control device 50 operates the stepping motor 25 to move the base 23 to a position where the lock pin 24 contacts the wall of the second engagement recess 23b that is on the first engagement recess 23a side. This corrects the standby position. The detection of contact is not particularly limited and can be performed by known means. For example, contact can be determined by detecting a value of the sensor 26 indicating a contact position, or by detecting an increase in the torque value of the stepping motor 25 due to contact (in this case, a separate torque sensor (not shown) is arranged on the stepping motor 25 and the control device 50 is configured to receive the signal).

[0071] [Step S18] In step S18, the base 23 moves to the connected position, the on-off valve 15 connects to the push rod 30a, and the hydrogen tank 11 and the hydrogen supply pipe 31 communicate with each other. Specifically, the control device 50 operates the stepping motor 25 to move the base 23, and as shown in Figure 17, the base 23 moves closer to the push rod 30a, and the push rod 30a is inserted into the insertion hole 17a of the on-off valve 15 and presses the valve body 16. In step S18, the lock pin 24 is inserted inside the second engagement recess 23b, so the amount of movement of the base 23 is limited, and excessive movement of the base 23 can be prevented.

[0072] [Effects of Hydrogen Tank Connection Control S10] The hydrogen consumption system 10 and its hydrogen tank connection control S10 described above can prevent poor hydrogen supply and hydrogen shutoff due to poor contact between the on-off valve 15 of the hydrogen tank 11 and the connection part 30 (push rod 30a) of the hydrogen consumption device 20 when the hydrogen tank 11 is attached or detached. More specifically, rather than placing the hydrogen tank 11 on the base 23 and then directly connecting the hydrogen tank 11 to the push rod 30a as shown in Figure 11, control is performed to establish a standby position as shown in steps S14 to S17, thereby performing positioning in two stages, improving positioning accuracy and achieving the above-mentioned effects. Furthermore, by limiting the movement of the base 23 with the lock pin 24, the accuracy of the origin and correction during positioning can be improved, and deterioration of positioning control performance due to manufacturing variations and deterioration over time can be suppressed.

[0073] 2. Hydrogen Consumption System Equipped with an Oxygen Concentration Reduction Mechanism In the hydrogen consumption system 10 described above, the hydrogen tank 11 is assumed to be detachably attached to the hydrogen consumption device 20. Therefore, air exists in the piping of the detachment section, which is open when the hydrogen tank is not installed. If a hydrogen tank is attached and operation of the system is started in this state, hydrogen containing air will be supplied to the hydrogen consumption device (fuel cell or hydrogen engine). If a fuel cell is used as the hydrogen consumption device and a hydrogen tank is attached and operation of the hydrogen consumption device is started, the air will be mixed into the hydrogen supply piping that supplies hydrogen from the hydrogen tank to the hydrogen consumption device, and the hydrogen will be supplied to the fuel cell. If a certain amount of air is mixed into the anode side (hydrogen supply side) of the fuel cell, a region of high air density will be created on the anode side of the fuel cell. In this region of high air density, an abnormal potential higher than the normal reaction potential will be generated in part of the cell; the carbon support used in the catalyst will be oxidized by oxygen in the air, reducing catalytic performance; or a reaction (combustion) will occur between hydrogen and oxygen contained in the air on the anode side, causing sintering due to the reaction heat, resulting in catalyst degradation. These problems are even more pronounced in hydrogen consumption devices equipped with detachable hydrogen tanks, where air contamination occurs every time the tank is attached or detached. Furthermore, when a hydrogen engine is used as the hydrogen consumption device, oxygen contamination in the hydrogen supply pipe that supplies hydrogen to the hydrogen engine can cause the ratio of hydrogen injected into the hydrogen engine's cylinders to oxygen supplied to the combustion chamber from the intake pipe to be lean relative to the target air-fuel ratio. Running a hydrogen engine on a lean fuel mixture during startup can result in poor startability, such as rotational fluctuations and a longer startup time.

[0074] Therefore, in this disclosure, a device (oxygen concentration reduction mechanism) that reduces the amount of mixed oxygen that reaches the hydrogen consuming device is provided in the hydrogen consuming device. In this disclosure, the oxygen concentration reduction mechanism is provided in the hydrogen consuming device on the hydrogen supply piping, that is, on the hydrogen supply piping side of the hydrogen tank's on-off valve. This makes it possible to reduce the oxygen concentration on the hydrogen consuming device side, regardless of the hydrogen tank's condition, which changes each time it is repeatedly attached / detached and refilled with hydrogen. This allows for stable and highly accurate reduction of the oxygen concentration.

[0075] Four types of hydrogen consumption devices and their systems will be described below, each differing in the type of oxygen concentration reduction mechanism provided in the hydrogen supply pipe.

[0076] 3.1. Configuration 1 Figure 18 is a diagram illustrating a hydrogen consumption device 20a and a hydrogen consumption system 10a according to Configuration 1, and corresponds to Figure 1. As can be seen from Figure 18, the hydrogen consumption system 10a has a hydrogen tank 11 and a hydrogen consumption device 20a. Here, the hydrogen tank 11 can be considered to be the same as the hydrogen tank 11 described above, and therefore a description thereof will be omitted.

[0077] The hydrogen consumption device 20a differs from the hydrogen consumption device 20 described above in that it includes an oxygen treatment member 100 as an oxygen concentration reduction mechanism. Other components are the same as those of the hydrogen consumption device 20 described above. The oxygen treatment member 100, which serves as the oxygen concentration reduction mechanism of this embodiment, is disposed within the hydrogen supply pipe 31 and prevents oxygen that reaches the oxygen treatment member 100 from advancing further toward the hydrogen consumption devices 40, 41, at least in the form of oxygen. Specifically, the oxygen treatment member 100 can be a hydrogen separation membrane that separates hydrogen while allowing hydrogen to pass through and preventing oxygen from passing through, or a catalyst that promotes the conversion of hydrogen to water by reacting with oxygen (oxidizing (combusting) hydrogen). The hydrogen separation membrane is not particularly limited, and known membranes can be used, including, for example, metal membranes such as palladium and membranes made of polymeric materials such as polyimide. These membranes allow hydrogen to pass through while restricting oxygen permeation, thereby suppressing the inflow of oxygen while supplying hydrogen to the hydrogen consumption devices 40, 41. Platinum can be used as the catalyst, and a porous material supporting platinum can be used as the oxygen treatment member. According to this, oxygen reacts with hydrogen to turn into water, and therefore oxygen is prevented from being supplied to the hydrogen consuming devices 40, 41 in the form of oxygen.

[0078] The oxygen treatment member 100 is disposed somewhere in the hydrogen supply pipe 31 from the connection part 30 to the hydrogen consuming devices 40, 41. It is preferable that the oxygen treatment member 100 be disposed somewhere in the hydrogen supply pipe 31 between the first pressure gauge 32 and the pressure reducing valve 36, where the pressure inside the pipe is high. The high pressure inside the pipe can increase the efficiency of oxygen concentration reduction by the oxygen treatment member 100. More preferably, the oxygen treatment member 100 is disposed in the hydrogen supply pipe 31 between the filter 35 and the pressure reducing valve 36. After foreign matter larger than oxygen is removed by the filter 35, the oxygen concentration is reduced by the oxygen treatment member 100, thereby enabling efficient reduction of the oxygen concentration.

[0079] Figure 19 is a diagram illustrating the hydrogen consumption device 20a according to form 1, the hydrogen consumption device 20a' which is a modified example of the hydrogen consumption system 10a, and the hydrogen consumption system 10a', and is equivalent to Figure 1. As can be seen from Figure 19, the hydrogen consumption system 10a' has a hydrogen tank 11 and the hydrogen consumption device 20a'. Here, the hydrogen tank 11 can be considered to be the same as the hydrogen tank 11 described above, and therefore a description thereof will be omitted.

[0080] In hydrogen consumption device 20a', compared to hydrogen consumption device 20a, base 23, lock pin 24, stepping motor 25, and sensor 26 are not provided on mounting portion 21, and the hydrogen tank connection control S10 described above is not performed. In this modification, hydrogen tank 11 is attached and detached manually, but even in this type of hydrogen consumption device, the oxygen treatment member 100 provides the above-mentioned effects.

[0081] 3.2. Configuration 2 Figure 20 is a diagram illustrating a hydrogen consumption device 20b and a hydrogen consumption system 10b according to Configuration 2, and corresponds to Figure 1. As can be seen from Figure 20, the hydrogen consumption system 10b has a hydrogen tank 11 and a hydrogen consumption device 20b. Here, the hydrogen tank 11 can be considered to be the same as the hydrogen tank 11 described above, and therefore a description thereof will be omitted.

[0082] The hydrogen consuming device 20b differs from the hydrogen consuming device 20 described above in that it includes a control device 50b that functions as an oxygen concentration reduction mechanism. Other components are the same as those of the hydrogen consuming device 20 described above. The control device 50b that functions as the oxygen concentration reduction mechanism in this embodiment also suppresses the concentration of oxygen mixed into the hydrogen supply pipe 31 and reduces the amount of oxygen reaching the hydrogen consuming devices 40, 41. In this embodiment, this function is achieved through control by the control device 50b. The configuration of the control device 50b itself can be considered to be similar to that of the control device 50 described above. Figure 21 shows the flow of control S20 (oxygen concentration reduction control) by the control device 50b as the oxygen concentration reduction mechanism in embodiment 2. As can be seen from Figure 21, the oxygen concentration reduction control S20 further includes steps S21 and S22 after the on-off valve 15 is opened via steps S11 to S18 described above.

[0083] [Step S21] In step S21, the residual pressure (P ｃ ) is the threshold value of the minimum allowable pressure (P ｍ ) or greater than (P ｃ >P ｍ The meaning of this is as follows: If the volume of the hydrogen tank 11 is V ｔ (L), the pressure inside the hydrogen tank 11 is P (MPa), and the volume of the hydrogen supply pipe 31 from the connection part 30 to the pressure reducing valve 36 is V. ｐ (L), and the volume of the hydrogen supply pipe 31 from the connection part 30 to the check valve 33 is V ｏ (L), the air concentration n (%) in the hydrogen contained between the tank 11 and the pressure reducing valve 36 can be expressed by the following equation (1):

[0084]

[0085] Here, V ｏ is the volume of the piping area into which air is likely to enter when the hydrogen tank is removed, and V ｔ and V are the volumes of the piping areas that become high pressure when the hydrogen tank is installed. The specific values ​​of these volumes can be obtained by multiplying the flow path cross-sectional area of ​​the piping by the piping length. The amount of gas contained in the hydrogen tank is proportional to the pressure inside the hydrogen tank, so V ｔ × P is an index that represents the actual amount of hydrogen contained in the hydrogen tank. ｐ × P is an index that indicates the actual amount of hydrogen in the pipe. ０ is an index representing the amount of air at normal pressure in the piping. The value of P at this time can be the value measured by the first pressure gauge 32. That is, V ０ The inside of the pipe is air at normal pressure, ｔ Hydrogen tank and V ｐ The piping will contain compressed hydrogen.

[0086] Looking at equation (1), V ｔ , V ｐ , V ｏis a value determined by the device, and as the pressure P inside the hydrogen tank decreases, n, which is the ratio of the air concentration (i.e., oxygen concentration) in the hydrogen, increases. A higher air concentration means a higher oxygen concentration, which causes the above-mentioned problems in fuel cells. Therefore, it is necessary to find out in advance the air concentration at which problems will occur in the hydrogen-consuming device, and set the residual pressure P in the hydrogen tank at that time to the threshold value of the minimum allowable pressure P. ｍ The current residual pressure P of the hydrogen tank (in step S21) is P ｃ When this is done, P ｃ P ｍ If it is larger than this, problems with hydrogen-consuming equipment caused by the air concentration (oxygen concentration) are unlikely to occur.

[0087] In step S21, the residual pressure P ｃ P ｍ If it is greater than the pressure P, the answer is Yes, the supply of hydrogen continues, and the determination in step S21 is repeated. ｃ P ｍ If it is below this level, the concentration of oxygen reaching the hydrogen consuming device may become high, which may cause problems, so the answer is No and the process proceeds to step S22.

[0088] [Step S22] In step S22, in response to the determination result of step S21, the on-off valve 15 is closed to terminate the supply of hydrogen. To close the valve, the control device 50b may operate the stepping motor 25 to place the hydrogen tank 11 in a standby state, or a separate mechanism may be provided that automatically closes the valve by turning off the power to the hydrogen consumption system. However, it is preferable to notify the operator of the reason for the valve closure (by displaying or sounding the message). The operator, knowing the reason, can take appropriate action, such as replacing the hydrogen tank.

[0089] [Effects, etc.] With the oxygen concentration reduction mechanism using the control device 50b described above, even if a hydrogen tank is used that is repeatedly attached, detached, and filled with hydrogen, and whose condition changes each time, the hydrogen consumption device can smoothly identify a condition in which the concentration of oxygen reaching the hydrogen consumption device is likely to become high and quickly stop this, thereby making it possible to reduce the concentration of oxygen reaching the hydrogen consumption device.

[0090] 2.3. Configuration 3 Figure 22 is a diagram illustrating a hydrogen consumption device 20c and a hydrogen consumption system 10c according to Configuration 3, and corresponds to Figure 1. As can be seen from Figure 22, the hydrogen consumption system 10c has a hydrogen tank 11 and a hydrogen consumption device 20c. Here, the hydrogen tank 11 can be considered to be the same as the hydrogen tank 11 described above, and therefore a description thereof will be omitted.

[0091] The hydrogen consuming device 20c is equipped with a switching valve 300, a hydrogen treatment member 100, and a control device 50c as an oxygen concentration reducing mechanism in comparison with the hydrogen consuming device 20 described above. The other equipment is the same as that of the hydrogen consuming device 20 described above.

[0092] In this embodiment, a pipe 301 is provided that forms a flow path (bypass) parallel to the hydrogen supply pipe 31, and the oxygen treatment member 100 described in embodiment 1 is provided in this pipe 301. A switching valve 300 switches between flowing hydrogen through the pipe 301 to use the oxygen treatment member 100, or not flowing hydrogen through the pipe 301 and using the normal hydrogen supply pipe 31. The switching valve 300 is electrically connected to a control device 50c and is configured to operate in response to a signal from the control device 50c. The positions at which the switching valve 300, the pipe 301, and the oxygen treatment member 100 are disposed are not particularly limited, but can be considered to be similar to the oxygen treatment member 100 described in embodiment 1 above.

[0093] 23 shows the flow of control S30 (oxygen concentration reduction control) by the control device 50c in form 3. As can be seen from Fig. 23, the oxygen concentration reduction control S30 includes steps S31 and S32 after the on-off valve 15 is opened through steps S11 to S18 described above. Step S31 can be considered the same as step S21 described in form 2 above.

[0094] In step S32, when the answer is No in step S31, the control device 50c operates the switching valve 300 to cause hydrogen to flow through the pipe 301. As a result, the hydrogen passes through the oxygen treatment member 100, and the hydrogen can be supplied to the hydrogen consuming devices 40, 41 with a reduced acidity concentration, as in the first embodiment.

[0095] As a modification of the third embodiment, the control device 50c can also perform the following control. In this modification, the control device 50c operates the switching valve 300 for a predetermined time from immediately after the hydrogen tank 11 is connected to the hydrogen consumption device 20c and hydrogen supply begins, causing hydrogen to flow through the piping 301 and into the oxygen treatment device 100. After the predetermined time has elapsed, the control device 50c operates the switching valve 300 to allow hydrogen to flow through the hydrogen supply piping 31, which is the normal piping. Since air (oxygen) contamination is most likely to occur when hydrogen supply begins after the hydrogen tank 11 is connected, this allows the oxygen treatment element 100 to reduce the oxygen concentration at that time and not use the oxygen treatment element 100 at other times, thereby improving the life of the oxygen treatment element 100 and suppressing an increase in pressure loss caused by using the oxygen-concentration treatment element 100 even when oxygen concentration reduction is not necessary.

[0096] Although the above describes examples in which the timing for switching the hydrogen path by the switching valve 300 is based on the residual pressure in the hydrogen tank and after a predetermined time has elapsed, it is also possible to control the switching of the switching valve 300 by measuring the oxygen concentration in the hydrogen supply pipe 31 with a sensor and switching the switching valve 300 when the obtained oxygen concentration falls below a predetermined value. That is, in addition to being based on the residual pressure in the hydrogen tank as the timing for switching the hydrogen path by the switching valve 300, the switching valve may be controlled so that hydrogen flows through the bypass when it is determined that the oxygen concentration in the hydrogen supply pipe 31 is below a predetermined value after the hydrogen tank 11 is installed. As an example of controlling the switching, the above-mentioned methods are based on the elapse of a predetermined time and the obtained oxygen concentration value.

[0097] 2.4. Configuration 4 Figure 24 is a diagram illustrating a hydrogen consumption device 20d and a hydrogen consumption system 10d according to Configuration 4, and corresponds to Figure 1. As can be seen from Figure 24, the hydrogen consumption system 10d has a hydrogen tank 11 and a hydrogen consumption device 20d. Here, the hydrogen tank 11 can be considered to be the same as the hydrogen tank 11 described above, and therefore a description thereof will be omitted.

[0098] The hydrogen consumption device 20c is equipped with a switching valve 400, a discharge pipe 401, and a control device 50d as an oxygen concentration reducing mechanism in comparison with the hydrogen consumption device 20 described above. The other equipment is the same as that of the hydrogen consumption device 20 described above.

[0099] In this embodiment, a discharge pipe 401 is provided which forms a flow path (bypass) parallel to the hydrogen supply pipe 31, and the fluid (hydrogen, oxygen) in the hydrogen supply pipe 31 is discharged from this discharge pipe 401 to the atmosphere. A switching valve 400 switches between discharging the fluid from the discharge pipe 401 and using the normal hydrogen supply pipe 31 without discharging. The switching valve 400 is electrically connected to a control device 50c and is configured to operate in response to a signal from the control device 50c. The positions at which the switch valve 400 and the discharge pipe 401 are disposed are not particularly limited, but can be considered to be similar to the oxygen treatment member 100 described in the first embodiment above.

[0100] 25 shows the flow of control (oxygen concentration reduction control) S40 by the control device 50d in form 4. As can be seen from Fig. 25, the oxygen concentration reduction control S40 includes steps S41, S42, and S43 after the on-off valve 15 is opened through steps S11 to S18 described above. Step S41 can be considered the same as step S21 described in form 2 above.

[0101] In step S42, when the determination in step S41 is No, the control device 50d operates the switching valve 400 to cause the fluid to flow through the discharge pipe 401. As a result, the fluid is discharged into the atmosphere, and therefore, hydrogen with a high oxygen concentration is not supplied to the hydrogen consuming devices 40, 41.

[0102] In step S43, after the fluid is released into the atmosphere from the release pipe 401 by the switching valve 400, the control device 50d operates the switching valve 400 and controls it to supply the fluid again to the hydrogen supply pipe 31. As a result, the fluid is supplied from the hydrogen supply pipe 31 to the hydrogen consuming devices 40, 41. The switching of the switching valve 400 can be performed after a predetermined time has elapsed or based on the oxygen concentration obtained by the oxygen concentration sensor.

[0103] As a modification of the fourth embodiment, the control device 50d can also perform the following control. In this modification, the control device 50d operates the switching valve 400 for a predetermined time period immediately after the hydrogen tank 11 is connected to the hydrogen consuming device 20c and the supply of hydrogen begins, causing the fluid to flow through the release pipe 401 and release the fluid to the atmosphere. After the predetermined time period has elapsed, the control device 50d operates the switching valve 400 to allow the hydrogen to flow through the hydrogen supply pipe 31, which is the normal pipe. Since air (oxygen) contamination is most likely to occur at the start of hydrogen supply after the connection of the hydrogen tank 11, this releases the fluid to the atmosphere at that time, preventing fluid with a high oxygen concentration from reaching the hydrogen consuming devices 40, 41, and does not release the fluid at other times, thereby providing hydrogen with a low oxygen concentration to the hydrogen consuming devices 40, 41.

[0104] Although the above describes examples in which the timing for switching the hydrogen path by the switching valve 400 is based on the residual pressure in the hydrogen tank and after a predetermined time has elapsed, it is also possible to measure the oxygen concentration in the hydrogen supply pipe 31 with a sensor and control the switching of the switching valve 400 based on the obtained oxygen concentration. That is, in addition to the timing for switching the hydrogen path by the switching valve 400 being based on the residual pressure in the hydrogen tank, the switching valve may also be controlled so that hydrogen flows through the bypass when it is determined that the oxygen concentration in the hydrogen supply pipe 31 is below a predetermined value after the hydrogen tank 11 is installed. As an example of controlling the switching, the above-mentioned cases are based on the elapse of a predetermined time and the obtained oxygen concentration value.

[0105] DESCRIPTION OF SYMBOLS 10a, 10b, 10c, 10d... Hydrogen consumption system, 11... Hydrogen tank, 15... On-off valve, 16... Valve body, 17... Connection portion, 20a, 20b, 20c, 20d... Hydrogen consumption device, 21... Mounting portion, 22... Storage hole, 23... Base, 24... Lock pin, 25... Stepping motor, 30... Connection portion, 31... Hydrogen supply piping, 32... First pressure gauge, 33... Check valve, 34... Second pressure gauge, 35... Filter, 36... Pressure reducing valve, 37... Third pressure gauge, 39... Injection, 40... Fuel cell (hydrogen consumption device), 41... Hydrogen engine (hydrogen consumption device), 50... Control device, 50b, 50c, 50d... Control device (oxygen concentration reduction mechanism), 100... Oxygen treatment member (oxygen concentration reduction mechanism)

Claims

1. A hydrogen consumption device comprising a hydrogen consumption device that is connected to a detachable hydrogen tank and consumes hydrogen from the hydrogen tank, wherein an oxygen concentration reduction mechanism is disposed in the hydrogen supply piping from when the hydrogen leaves the hydrogen tank to when it reaches the hydrogen consumption device, for reducing the concentration of oxygen mixed in the hydrogen and supplying hydrogen to the hydrogen consumption device.

2. The hydrogen consumption device described in claim 1, wherein the oxygen concentration reduction mechanism is an oxygen treatment member arranged in the hydrogen supply pipe through which hydrogen flows from the hydrogen tank to the hydrogen consumption device, and reduces the oxygen concentration downstream of the oxygen concentration reduction mechanism compared to the upstream side.

3. The hydrogen consumption device according to claim 2, wherein the oxygen treatment member is provided in the hydrogen supply pipe and comprises a hydrogen separation membrane that allows hydrogen to pass through but not oxygen, or a catalyst that reacts hydrogen and oxygen to convert them into water.

4. The hydrogen consumption device according to claim 2, wherein the oxygen reduction mechanism is a release pipe that releases the fluid in the hydrogen supply pipe to the atmosphere.

5. A hydrogen consumption device as described in claim 1, wherein the oxygen concentration reduction mechanism comprises: an oxygen treatment member arranged in a bypass branched from the hydrogen supply pipe, which reduces the oxygen concentration downstream of the oxygen concentration reduction mechanism compared to the oxygen concentration upstream thereof; a switching valve which switches the flow path between the hydrogen supply pipe and the bypass; and a control device which controls the switching valve, wherein the control device controls the switching valve so that the hydrogen flows through the bypass when it is determined that the oxygen concentration is below a predetermined value after the hydrogen tank is installed.

6. The hydrogen consuming device according to claim 5, wherein the determination is made by determining whether the hydrogen flows through the bypass for a predetermined time after the hydrogen tank is attached to the hydrogen consuming device.

7. The hydrogen consumption device according to claim 5, wherein the determination is made by detecting a decrease in oxygen concentration using an oxygen concentration sensor after the hydrogen tank is attached to the hydrogen consumption device.

8. A hydrogen consumption device as described in claim 1, wherein the oxygen concentration reduction mechanism comprises: an oxygen treatment member arranged in a bypass branched off from the hydrogen supply pipe through which hydrogen flows from the hydrogen tank to the hydrogen consumption device, and which reduces the oxygen concentration downstream of the oxygen concentration reduction mechanism compared to the oxygen concentration upstream thereof; a switching valve which switches the flow path between the hydrogen supply pipe and the bypass; and a control device which controls the switching valve, wherein the control device operates the switching valve so that hydrogen flows into the bypass when the residual pressure in the hydrogen tank is equal to or lower than a predetermined pressure.

9. A hydrogen consumption system comprising a hydrogen tank and a hydrogen consumption device according to any one of claims 1 to 8.

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