Mobile machine system and method for operating mobile machine

Abstract

Provided is a system that makes it possible to operate continuously and efficiently a mobile machine moving in a work area. The system comprises: a plurality of hydrogen gas tanks; a mobile machine including a drive source that uses hydrogen gas stored in each of the hydrogen gas tanks; and a hydrogen supply facility that is installed in the work area and supplies hydrogen gas to the hydrogen gas tank. Each hydrogen gas tank is attachable to and detachable from the mobile machine. The hydrogen supply facility is configured to be capable of supplying hydrogen gas to both a hydrogen gas tank detached from the mobile machine and a hydrogen gas tank attached to the mobile machine from among the plurality of hydrogen gas tanks. The hydrogen supply facility includes a cooling unit for cooling the hydrogen gas tank to which the hydrogen gas is supplied.

Description

Mobile machine system and mobile machine operation method

[0001] TECHNICAL FIELD The present disclosure relates to mobile machine systems and methods of operating mobile machines.

[0002] In recent years, with environmental considerations in mind, the use of hydrogen as a fuel for power generation and automobiles has been considered, and demand for hydrogen is increasing. Japanese Patent Laid-Open Publication No. 2003-213728 (Patent Document 1) describes a work machine powered by a fuel cell that uses hydrogen gas. Specifically, the work machine includes a container that contains a hydrogen storage alloy for the fuel cell and functions as a counterweight. Hydrogen gas is supplied from the container to the fuel cell, which operates the work machine.

[0003] However, because work machines require greater power than, for example, private vehicles, the containers may need to be frequently replenished with hydrogen gas. Furthermore, work machines that cannot travel on public roads may not be able to travel to hydrogen stations or other locations located outside the work area to replenish hydrogen gas. These factors may prevent the work machines from operating continuously and efficiently.

[0004] Japanese Patent Application Laid-Open No. 2003-213728

[0005] The present disclosure aims to provide a mobile machine system that allows a mobile machine to be operated continuously and efficiently.

[0006] The mobile machine system includes a mobile machine that moves within a predetermined working area and includes a plurality of hydrogen gas tanks, each capable of storing hydrogen gas, a drive source that uses the hydrogen gas stored in each of the hydrogen gas tanks, and a hydrogen supply equipment installed within the working area that supplies hydrogen gas to each of the hydrogen gas tanks. Each of the plurality of hydrogen gas tanks can be attached and detached to the mobile machine. The hydrogen supply equipment is configured to be able to supply hydrogen gas to both hydrogen gas tanks detached from the mobile machine and hydrogen gas tanks attached to the mobile machine. The hydrogen supply equipment includes a cooling unit that cools the hydrogen gas tank to which the hydrogen gas is supplied.

[0007] Fig. 1 is a flow sheet showing a mobile machine system according to a first embodiment of the present disclosure. Fig. 2 is a flow sheet showing a mobile machine system according to a second embodiment of the present disclosure. Fig. 3 is a cross-sectional view showing an example of a hydrogen gas tank attached to the mobile machine systems shown in Figs. 1 and 2, respectively. Fig. 4 is a cross-sectional view showing a hydrogen storage module included in the hydrogen gas tank.

[0008] Before describing specific embodiments of the present disclosure, an outline of the present disclosure will be provided.

[0009] The mobile machine system disclosed herein includes a mobile machine that moves within a predetermined working area and includes a plurality of hydrogen gas tanks, each capable of storing hydrogen gas, a drive source that uses the hydrogen gas stored in each of the hydrogen gas tanks, and a hydrogen supply device installed within the working area and that supplies hydrogen gas to each of the hydrogen gas tanks. Each of the plurality of hydrogen gas tanks is detachable from the mobile machine. The hydrogen supply device is configured to be able to supply hydrogen gas to both hydrogen gas tanks detached from the mobile machine and hydrogen gas tanks attached to the mobile machine. The hydrogen supply device includes a cooling unit that cools the hydrogen gas tank to which hydrogen gas is supplied.

[0010] The driving source of the mobile machine uses hydrogen gas stored in the hydrogen gas tank, thereby reducing the burden on the global environment. The hydrogen supply equipment of the mobile machine system is capable of supplying hydrogen gas to both a hydrogen gas tank detached from the mobile machine and a hydrogen gas tank attached to the mobile machine, allowing the mobile machine to operate continuously and efficiently. The cooling unit of the hydrogen supply equipment cools the hydrogen gas tank to which hydrogen gas is supplied, allowing hydrogen gas to be efficiently supplied to the hydrogen gas tank. This makes it possible to replace a hydrogen gas tank attached to the mobile machine whose hydrogen gas has been consumed with a hydrogen gas tank filled with hydrogen gas by the hydrogen supply equipment at the desired timing, thereby improving the ease with which the mobile machine can operate continuously and efficiently.

[0011] Preferably, the cooling unit includes a pipeline through which cooling water is supplied to the hydrogen gas tank, allowing the hydrogen gas tank to be easily cooled.

[0012] It is preferable that the cooling unit further includes a cooling water tank for storing cooling water, and a cooling water pump for supplying the cooling water stored in the cooling water tank to the hydrogen gas tank through the pipeline, which makes it possible to supply cooling water to the hydrogen gas tank with simple equipment.

[0013] The hydrogen supply equipment may further include a pressure reducing unit that reduces the pressure of the hydrogen gas supplied to the hydrogen gas tank. The reduction in pressure of the hydrogen gas by the pressure reducing unit allows the hydrogen gas to be supplied to the hydrogen gas tank with higher efficiency.

[0014] The hydrogen supply equipment may further include a flow rate adjusting unit that adjusts the flow rate of hydrogen gas supplied to the hydrogen gas tank. The flow rate adjusting unit makes it possible to improve the efficiency with which hydrogen gas is supplied to the hydrogen gas tank.

[0015] The hydrogen supply equipment may further include a compression unit that compresses the hydrogen gas to be supplied to the hydrogen gas tank. The compression unit enables the hydrogen gas to be supplied to the hydrogen gas tank with improved efficiency.

[0016] Specifically, the compression unit preferably includes a compressor that operates to compress hydrogen gas supplied to the hydrogen gas tank, a reflux path that is arranged to allow a portion of the hydrogen gas compressed by the compressor to be refluxed upstream of the compressor, a pressure regulating valve that is arranged in the reflux path, and a pressure regulator that opens the pressure regulating valve to allow hydrogen gas to flow through the reflux path when the pressure of the hydrogen gas compressed by the compressor reaches or exceeds a set value. This enables hydrogen gas to be efficiently supplied to the hydrogen gas tank at a regulated pressure.

[0017] The hydrogen supply facility may include a hydrogen cartridge for storing hydrogen gas. The hydrogen cartridge allows the hydrogen supply facility to be a simple facility.

[0018] The hydrogen supply equipment may further include a plurality of hydrogen cartridges, each containing hydrogen gas, and a selection unit that selects a hydrogen cartridge from the plurality of hydrogen cartridges to supply hydrogen gas to the hydrogen gas tank, thereby enabling a sufficient amount of hydrogen gas to be supplied to the hydrogen gas tank.

[0019] Also provided is a method for operating a mobile machine that moves within a predetermined working area, comprising the steps of: preparing a plurality of hydrogen gas tanks, each capable of storing hydrogen gas, and the mobile machine including a power source that uses the hydrogen gas stored in the plurality of hydrogen gas tanks, installing a hydrogen supply facility within the working area that supplies hydrogen gas to the hydrogen gas tanks, operating the mobile machine with a first hydrogen gas tank selected from the plurality of hydrogen gas tanks attached to the mobile machine, detaching the first hydrogen gas tank from the mobile machine after the hydrogen gas in the first hydrogen gas tank is consumed by operation of the mobile machine, attaching a second hydrogen gas tank selected from the plurality of hydrogen gas tanks to the mobile machine from which the first hydrogen gas tank has been detached, and supplying hydrogen gas to the first hydrogen gas tank detached from the mobile machine using the hydrogen supply facility.

[0020] According to the above operation method, the mobile machine can be continuously operated by detaching the first hydrogen gas tank from the mobile machine that has consumed the hydrogen gas in the first hydrogen gas tank while moving within the specified work area, and attaching the second hydrogen gas tank filled with hydrogen gas to the mobile machine. Furthermore, the hydrogen supply equipment supplies hydrogen gas to the first hydrogen gas tank detached from the mobile machine, allowing the first hydrogen gas tank to be circulated and used. Furthermore, by installing the hydrogen supply equipment within the work area, the mobile machine does not need to travel far to replenish its hydrogen gas, thereby improving the continuity and efficiency of the operation.

[0021] The operating method may further include a step of supplying hydrogen gas to a third hydrogen gas tank selected from the plurality of hydrogen gas tanks and to be mounted on the mobile machine by the hydrogen supply equipment. The supply of hydrogen gas to the third hydrogen gas tank to be mounted on the mobile machine in the future allows the mobile machine to be more reliably replenished with hydrogen gas, and allows the mobile machine to operate more easily and continuously.

[0022] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0023] FIG. 1 shows a mobile system according to a first embodiment, and FIG. 2 shows a mobile machine system according to a second embodiment. Each of the mobile machine systems is a system including a mobile machine 20 that moves within a predetermined work area and means for operating the mobile machine 20. In addition to the mobile machine 20, the system includes a plurality of hydrogen gas tanks 10, each of which stores hydrogen gas, and a hydrogen supply device. The hydrogen supply device according to the first embodiment is the hydrogen supply device 30A shown in FIG. 1, and the hydrogen supply device according to the second embodiment is the hydrogen supply device 30B shown in FIG. 2. The mobile machine 20 has a drive source (not shown) that uses hydrogen gas stored in the hydrogen gas tanks 10. The hydrogen supply device 30 is installed within the work area and supplies hydrogen gas to each of the hydrogen gas tanks 10. The hydrogen gas tanks 10 are configured to be detachable from the mobile machine 20. The hydrogen supply equipment 30 is configured to be able to supply hydrogen gas to each of the multiple hydrogen gas tanks 10, including the hydrogen gas tank 10 detached from the mobile machine 20 and the hydrogen gas tank 10 attached to the mobile machine 20.

[0024] The work area can be set in various ways. Examples of the work area include construction sites, disaster recovery sites, the inside of facilities, lakes, lakesides including rivers, river banks, remote islands including surrounding sea areas, and offshore structures. Examples of the facility include factories, schools, hospitals, amusement parks, airports, and ports. The work area is not limited to the ground, but may also include the airspace above it, for example, territorial airspace.

[0025] The drive source of the mobile machine 20 may be any one that uses hydrogen gas, and examples of the drive source include a fuel cell, an internal combustion engine that burns hydrogen gas, and others. The mobile machine 20 may be any one that operates within the work area, and examples of the mobile machine 20 include construction machines, transportation machines, and specialized machines (dedicated machines). Examples of construction machines include shovels, cranes, and dump trucks. Examples of transportation machines include forklifts, trucks, buses, ships, and aircraft. The specialized machines are machines that have one or more specialized functions, such as the ability to tow an airplane. The mobile machine may be any one of a manned machine, a remotely operated machine, and an unmanned machine (autonomous machine).

[0026] Each of the hydrogen gas tanks 10 preferably contains a hydrogen storage alloy capable of absorbing and releasing hydrogen gas. By containing the hydrogen storage alloy, the hydrogen gas tank 10 can store a sufficient amount of hydrogen gas despite its small size. The shape and dimensions of the hydrogen gas tank 10 can be freely determined according to the specifications of the mobile machine 20. The hydrogen gas tank 10 is preferably designed to fit the shape of a tank mounting portion, which is a portion of the mobile machine 20 to which the hydrogen gas tank 10 is attached and detached.

[0027] 3 shows an example of the hydrogen gas tank 10 containing the hydrogen storage alloy. The hydrogen gas tank 10 shown in FIGS. 3 and 4 includes a plurality of hydrogen storage modules 12 and a casing 11 that houses the plurality of hydrogen storage modules 12.

[0028] As shown in FIG. 4 , each of the hydrogen storage modules 12 includes a heat transfer tube 121 , a plurality of hydrogen storage sections 122 , and a heat medium tube 123 .

[0029] The heat transfer tube 121 includes a cylindrical tube main body 121a and a plurality of fins 121b. The tube main body 121a is a substantially cylindrical member. The plurality of fins 121b are arranged at intervals in the axial direction of the tube main body 121a. Each of the fins 121b is an annular member protruding from the outer circumferential surface of the tube main body 121a toward the outside in the radial direction of the tube main body 121a. The tube main body 121a functions as a cartridge that allows the heat medium tube 123 to be inserted into or removed from the tube main body 121a.

[0030] The hydrogen storage units 122 are filled between adjacent fins 121b. Each of the hydrogen storage units 122 includes a plurality of hydrogen storage alloys 122b and a resin 122a that holds the hydrogen storage alloys 122b. The hydrogen storage units 122 as a whole form a coating layer that covers the outer circumferential surface of the tube main body 121a. Therefore, in the longitudinal cross section shown in FIGS. 3 and 4, each of the fins 121b is arranged to separate the coating layer made up of the hydrogen storage units 122. The coating layer made up of the hydrogen storage units 122 is fixed to the outer circumferential surface of the tube main body 121a and to the surfaces of the fins 121b that face the axial direction of the tube main body 121a. In this way, the heat transfer tube 121 and the hydrogen storage units 122 are integrally configured so as to be difficult to separate from each other.

[0031] The heat medium pipe 123 allows the heat medium to flow therethrough. Each of the hydrogen storage units 122 is capable of exchanging heat with the heat medium in the heat medium pipe 123 through the fins 121b of the heat transfer pipe 121 and the pipe body 121a. The hydrogen storage module 12 preferably further includes a heat transfer sheet 13, exemplified in Figures 3 and 4. The heat transfer sheet 13 is interposed between the pipe body 121a and the heat medium pipe 123 to promote heat conduction therebetween.

[0032] The heat medium pipe 123 has a double-pipe structure including an inner pipe 1231 and an outer pipe 1232. The inner pipe 1231 is cylindrical with both ends open. The outer pipe 1232 is cylindrical with one end (the left end in FIGS. 3 and 4 ) open and the other end (the right end in FIGS. 3 and 4 ) closed by an end wall, and the inner pipe 1231 is disposed radially inside the outer pipe 1232. The heat medium pipe 123 allows the heat medium to be supplied into the inner pipe 1231 and discharged through a gap between the outer pipe 1232 and the inner pipe 1231. In this way, the inner pipe 1231 and the outer pipe 1232 define a flow path for the heat medium.

[0033] Specifically, of the openings at both ends of the inner pipe 1231, a first opening on the same side as the open end of the outer pipe 1232 (the left side in FIGS. 3 and 4 ) functions as a heat medium inlet 1233, and the opening at the open end of the outer pipe 1232 functions as a heat medium outlet 1234. The heat medium flows into the inner pipe 1231 through the heat medium inlet 1233 and flows through the inner pipe 1231 toward a second opening of the inner pipe 1231 opposite the heat medium inlet 1233, i.e., an opening on the same side as the closed end of the outer pipe 1232 (the right side in FIGS. 3 and 4 ). The heat medium then flows from the second opening of the inner pipe 1231 into the outer pipe 1232, flows in the opposite direction, and is discharged from the heat medium outlet 1234. The heat medium exchanges heat with the hydrogen storage unit 122 via the heat transfer tubes 121 from when it flows into the heat medium tubes 123 until it is discharged. Each of the hydrogen storage modules 12 thus allows a cooling heat medium to flow within the hydrogen storage module 12, thereby promoting the occlusion of hydrogen gas by the hydrogen storage unit 122. Conversely, each of the hydrogen storage modules 12 allows a heating heat medium to flow within the hydrogen storage module 12, thereby promoting the release of hydrogen gas from the hydrogen storage unit 122.

[0034] The casing 11 includes a casing main body 110, a first holding member 111, a second holding member 112, and a third holding member 113. The casing main body 110 houses the multiple hydrogen storage modules 12. The first holding member 111 extends in a direction parallel to the module radial direction, which is the radial direction of the hydrogen storage module 12, and holds the end (left end in FIG. 3 ) of both end portions of the inner pipe 1231 that forms the heat medium inlet 1233. The second holding member 112 extends in a direction parallel to the module radial direction and holds the end (left end in FIG. 3 ) of both end portions of the outer pipe 1232 that forms the heat medium outlet 1234. The third holding member 113 extends in a direction parallel to the module radial direction and holds the end (right end in FIG. 3 ) of both end portions of the outer pipe 1232 that is blocked by the end wall. The plurality of hydrogen storage modules 12 are arranged in parallel in the radial direction of the module within the casing body 110 and are held by the first holding member 111 , the second holding member 112 and the third holding member 113 .

[0035] The first holding member 111 and the second holding member 112 also function as partition walls that form a flow path of the heat medium inside the casing main body 110. Specifically, the first holding member 111 is plate-shaped and has an inlet path-defining surface (left side surface in FIG. 3 ) and a first outlet path-defining surface (right side surface in FIG. 3 ) facing the opposite side, and the inlet path-defining surface, together with a part of the inner surface of the casing 11, defines a heat medium inlet path 114 for allowing the heat medium to flow into the heat medium inlet port 1233 of the inner pipe 1231. The second holding member 112 is plate-shaped and has a second outlet path defining surface (left side surface in FIG. 3 ) and a surface facing the opposite side, and the second outlet path defining surface, together with a part of the inner surface of the casing 11 and the first outlet path defining surface of the first holding member 111, defines a heat medium outlet path 115 for discharging the heat medium that has flowed out from the heat medium outlet port 1234 of the outer pipe 1232 to the outside of the casing 11. The casing main body 110 has a heat medium supply port 116 for supplying the heat medium to the heat medium inlet path 114 and a heat medium outlet port 117 for discharging the heat medium from the heat medium outlet path 115.

[0036] The casing body 110 further has a gas inlet 118 for allowing hydrogen gas supplied to the casing 11 to flow into the interior of the casing body 110, and a gas outlet 119 for allowing the hydrogen gas used to flow out from the interior of the casing body 110.

[0037] The hydrogen supply equipment, i.e., each of the hydrogen supply equipment 30A and 30B, is installed within the work area. The mobile machine 20 operating within the work area may be a mobile machine that cannot operate outside the work area. Such a mobile machine cannot, for example, drive itself to a hydrogen station or the like installed outside the work area to be replenished with hydrogen gas. By installing each of the hydrogen supply equipment 30A and 30B within the work area, the need for the mobile machine 20 to travel outside the work area is reduced, thereby enabling the efficiency of operation of the mobile machine within the work area to be improved.

[0038] The hydrogen supply equipment may be a simple equipment. Specifically, the hydrogen supply equipment is preferably one that can be easily installed and easily removed. For example, if the work area is a construction site or a disaster recovery site, the hydrogen supply equipment may be removed at the end of a predetermined operation period. If the hydrogen supply equipment is a simple equipment, it can be easily installed at the start of the operation period and easily removed at the end of the operation period.

[0039] The hydrogen supply equipment is configured to be able to supply hydrogen gas to both the hydrogen gas tank 10 detached from the mobile machine 20 and the hydrogen gas tank 10 attached to the mobile machine 20, among the multiple hydrogen gas tanks 10. This eliminates the need for the hydrogen supply equipment to directly supply hydrogen gas to the mobile machine 20. There is a risk that the mobile machine 20 may be unable to operate while hydrogen gas is being directly supplied to the mobile machine 20. Detaching the hydrogen gas tank 10 from the mobile machine 20 after the hydrogen gas in the hydrogen gas tank 10 has been consumed, and attaching the hydrogen gas tanks 10 filled with hydrogen gas by each of the hydrogen supply equipment 30A and 30B to the mobile machine 20, makes it possible to easily replenish the mobile machine 20 with hydrogen gas. In other words, by replacing the hydrogen gas tank 10 attached to the mobile machine 20, the operation of the mobile machine 20 can be resumed efficiently in a short time. In addition, the hydrogen supply equipment replenishes hydrogen gas into the hydrogen gas tank 10 detached from the mobile machine 20, thereby enabling the hydrogen gas tank 10 to be used in a circulated manner, thereby enabling the mobile machine system to be operated efficiently.

[0040] Each of the hydrogen supply facilities 30A, 30B includes a cooling tower 31, which functions as a cooling unit that cools the hydrogen gas tank 10 to which hydrogen gas is supplied. The cooling tower 31 includes a cooling water tank 311, a pipeline 312, and a cooling water pump 313. The cooling water tank 311 stores cooling water, which is a cooling heat medium for cooling the hydrogen gas tank 10. The pipeline 312 forms a supply path for supplying the cooling water in the cooling water tank 311 to the hydrogen gas tank 10, which is the object to be cooled, and a return path for returning the cooling water after cooling the hydrogen gas tank 10 to the cooling water tank 311. The cooling water pump 313 is provided in a portion of the pipeline 312 that forms the supply path, and operates to supply the cooling water in the cooling water tank 311 to the hydrogen gas tank 10 through the pipeline 312.

[0041] The cooling tower 31, which functions as the cooling unit in the first and second embodiments, supplies the cooling water (cooling heat medium) to the hydrogen gas tank 10 while hydrogen gas is being supplied to the heat medium pipe 123 of the hydrogen gas tank 10. The cooling water flowing through the heat medium pipe 123 of the hydrogen gas tank 10 suppresses heat generation in the hydrogen storage unit 122 of the hydrogen gas tank 10, thereby enabling hydrogen gas to be efficiently filled into the hydrogen gas tank 10.

[0042] The cooling unit, exemplified as the cooling tower 31, may include a water source such as the sea, lake, or river if the water source is located within or near the work area. In this case, the cooling unit preferably utilizes the latent heat of the water used as cooling water. This reduces the amount of power consumed to cool the cooling water, allowing the hydrogen supply facility 30A or 30B to be operated at reduced cost. If the drive source of the mobile machine 20 includes a fuel cell, the power consumption thereof is preferably equal to or less than the rated output of the fuel cell. Specifically, an example of an upper limit of the power consumption is 20%, preferably 15%, and more preferably 10% of the rated output. The lower limit of the power consumption is also not limited and may be, for example, 5% of the rated output.

[0043] Each of the hydrogen supply equipment 30A, 30B further includes a hydrogen gas supply unit. Specifically, the hydrogen gas supply unit is a hydrogen gas generator 32 that produces hydrogen gas to be supplied in the hydrogen supply equipment 30A shown in Fig. 1, and is at least one hydrogen card 33 that stores the hydrogen gas to be supplied in the hydrogen supply equipment 30B shown in Fig. 2. By including the hydrogen card 33, the hydrogen supply equipment 30B can be easily simplified and can be easily installed and removed.

[0044] The hydrogen supply equipment 30B preferably includes a plurality of hydrogen cards 33 and a selection unit 34, and the selection unit 34 selects a hydrogen card 33 from the plurality of hydrogen cards 33 to supply hydrogen gas to the hydrogen gas tank 10. The hydrogen supply equipment 30B is more preferably configured to supply hydrogen gas to the hydrogen gas tank 10 from a first hydrogen card 33 selected by the selection unit 34 from the plurality of hydrogen cards 33, and to supply hydrogen gas to the hydrogen gas tank 10 from another hydrogen card 33 selected by the selection unit 34 after the remaining amount of hydrogen gas in the first hydrogen card 33 has decreased. This makes it possible to ensure a sufficient amount of hydrogen gas to be supplied to the mobile machine 20, and to improve the continuity and efficiency of operation of the mobile machine 20.

[0045] In the hydrogen supply facility 30A, the hydrogen gas tank 10 is connected to the hydrogen gas generator 32 via a hydrogen supply pipe P1, and in the hydrogen supply facility 30B, the hydrogen gas tank 10 is connected to one of the plurality of hydrogen curdles 33 via the hydrogen supply pipe P1 and one of the plurality of curdle pipes P2. The hydrogen supply pipe P1 has an upstream end connected to the hydrogen gas supply unit and a downstream end on the opposite side thereof, and by connecting the downstream end to the gas inlet 118 of the hydrogen gas tank 10, it is possible to fill the hydrogen gas tank 10 with hydrogen gas from the hydrogen gas supply unit.

[0046] 2 includes the plurality of curdle pipes P2, a selection valve 341, and a pressure indicating regulator 342. The selection valve 341 has a plurality of inlet ports and outlet ports, the plurality of inlet ports being connected to the plurality of hydrogen curdle 33 via the plurality of curdle pipes P2, respectively, and the outlet port being connected to the upstream end of the hydrogen supply pipe P1. The pressure indicating regulator 342 detects the pressure in each of the plurality of curdle pipes P2, generates a command signal specifying the hydrogen curdle 33 to be used based on the detected pressure, and inputs the command signal to the selection valve 341. The selection valve 341 is configured to connect only the curdle pipe P2 of the plurality of curdle pipes P2 corresponding to the hydrogen curdle 33 specified by the command signal input to the selection valve 341 to the hydrogen supply pipe P1, and cut off the connection between the other curdle pipes P2 and the hydrogen supply pipe P1.

[0047] Each of the hydrogen supply equipment 30A, 30B preferably further includes a pressure reducing unit 35, which reduces the pressure of the hydrogen gas supplied to the hydrogen gas tank 10. The pressure reducing unit 35, illustrated in FIGS. 1 and 2, includes a pressure valve 351 and a pressure indicating regulator 352. The pressure valve 351 is disposed midway along the hydrogen supply pipe P1 and has a variable aperture. The pressure indicating regulator 352 detects the pressure of the hydrogen gas upstream of the pressure valve 351 and adjusts the aperture of the pressure valve 351 so that the detected pressure approaches a predetermined set pressure.

[0048] By including the pressure reducing section 35, each of the hydrogen supply equipment 30A, 30B eliminates the need for the hydrogen gas tank 10 to have pressure resistance sufficient to withstand the maximum pressure of the hydrogen gas supply section, thereby making it possible to manufacture the hydrogen gas tank 10 at reduced cost. In other words, the pressure reducing section 35 enables each of the hydrogen supply equipment 30A, 30B to stably and efficiently supply hydrogen gas even to a hydrogen gas tank 10 with a relatively low pressure resistance.

[0049] Each of the hydrogen supply devices 30A, 30B preferably further includes a flow rate adjustment unit 36, which adjusts the flow rate of hydrogen gas supplied to the hydrogen gas tank 10. The flow rate adjustment unit 36 ​​specifically includes a flow rate valve 361 and a flow rate indicator / adjuster 362. The flow rate valve 361 is disposed midway along the hydrogen supply pipe P1, specifically downstream of the pressure valve 351 in the example shown in FIGS. 1 and 2, and has a variable aperture. The flow rate indicator / adjuster 362 detects the flow rate of hydrogen gas upstream of the flow rate valve 361 and adjusts the aperture of the flow rate valve 361 so that the detected flow rate approaches a predetermined set flow rate. By including the flow rate adjustment unit 36, each of the hydrogen supply devices 30A, 30B enables the hydrogen gas to be supplied to the hydrogen gas tank 10 with improved efficiency. For example, it is possible to adjust the amount or time (filling rate) of hydrogen gas filled into the hydrogen gas tank 10 depending on the operating status of the mobile machine 20, the remaining number of hydrogen gas tanks 10 that have been filled with hydrogen gas but have not yet been attached to the mobile machine 20, the capacity of the hydrogen gas tank 10 and the remaining amount of hydrogen gas therein, and other factors.

[0050] 1 includes a compression section 37 that compresses the hydrogen gas to be supplied to the hydrogen gas tank 10. This allows the hydrogen gas to be supplied to the hydrogen gas tank 10 with improved efficiency.

[0051] Specifically, the compression unit 37 includes a compressor 371, a reflux path 372, a pressure regulating valve 373, and a pressure regulator. In the hydrogen supply facility 30A illustrated in FIG. 1, the pressure indicator / regulator 352 also functions as the pressure regulator. The compressor 371 is disposed in the hydrogen supply pipe P1, specifically, upstream of the pressure reducing unit 35, and operates to compress the hydrogen gas. The reflux path 372 is disposed to allow a portion of the hydrogen gas compressed by the compressor 371 to be refluxed upstream of the compressor 371. The pressure regulating valve 373 is disposed in the reflux path 372 and has a variable opening. The pressure regulator (the pressure indicator / regulator 352 in FIG. 1) detects the pressure of the hydrogen gas compressed by the compressor 371, and when the detected pressure exceeds a predetermined set value, opens the pressure regulating valve 373 to allow a portion of the hydrogen gas to be refluxed through the reflux path 372.

[0052] The compressor 371 compresses and pressurizes the hydrogen gas discharged from the hydrogen gas supply unit. The compressed hydrogen gas can be efficiently supplied to the hydrogen gas tank 10 even if the hydrogen gas discharged from the hydrogen gas supply unit is at a low pressure. On the other hand, to prevent excessive pressurization of the hydrogen gas by the compressor 371 from placing a heavy load on the hydrogen gas tank 10, the pressure indicator / adjuster 352 serving as the pressure regulator opens the pressure adjustment valve 373 when the pressure of the hydrogen gas compressed by the compressor 371 reaches or exceeds a set value, thereby returning a portion of the hydrogen gas in the hydrogen supply pipe P1 to a position upstream of the compressor 371, thereby adjusting the hydrogen gas supplied to the hydrogen gas tank 10 to approach a predetermined pressure.

[0053] The compression unit 37 preferably further includes a pressure adjustment mechanism, and in the example shown in FIG. 1 , a bypass passage 374 and a bypass valve 375. The bypass passage 374 is arranged to interconnect a portion of the return passage 372 downstream of the pressure adjustment valve 373 and a portion of the hydrogen supply pipe P1 upstream of the compressor 371. The bypass valve 375 is arranged midway along the bypass passage 374 so as to switch the bypass passage 374 between an open state and a closed state. The bypass valve 375 is preferably opened and closed as follows: when the pressure of the hydrogen gas discharged from the hydrogen gas supply unit is equal to or higher than a desired value, the bypass valve 375 is opened to allow the hydrogen gas to be supplied to the hydrogen gas tank 10 through the bypass passage 374. Conversely, when the pressure of the hydrogen gas discharged from the hydrogen gas supply unit drops, the bypass valve 375 is closed to allow the hydrogen gas to pass through the compressor 371 and be pressurized. This reduces the operation of the compressor 371, thereby reducing the operating costs of the hydrogen supply facility 30A.

[0054] The hydrogen supply equipment is preferably configured to be able to simultaneously supply hydrogen gas to a plurality of hydrogen gas tanks 10. Specifically, the hydrogen supply equipment preferably includes a plurality of hydrogen supply pipes P1 and a plurality of pipelines 312. This allows the hydrogen supply equipment to simultaneously supply hydrogen gas to a plurality of hydrogen gas tanks 10, thereby enabling a plurality of mobile machines 20 to operate continuously and efficiently.

[0055] The mobile machine 20 that moves within a predetermined work area as described above can be efficiently operated by a preferred operating method. The operating method includes a preparation step of preparing the plurality of hydrogen gas tanks 10 and a mobile machine 20 including a driving source that uses hydrogen gas stored in each of the hydrogen gas tanks 10; an installation step of installing hydrogen supply equipment (e.g., the hydrogen supply equipment 30A or the hydrogen supply equipment 30B) within the work area to supply hydrogen gas to the hydrogen gas tanks 10; an operation step of operating the mobile machine 20 equipped with a first hydrogen gas tank 10 selected from the plurality of hydrogen gas tanks 10; a detachment step of detaching the first hydrogen gas tank 10 from the mobile machine 20 after the hydrogen gas in the first hydrogen gas tank 10 is consumed by operation of the mobile machine 20; an attachment step of attaching a second hydrogen gas tank 10 selected from the plurality of hydrogen gas tanks to the mobile machine 20; and a supply step of supplying hydrogen gas to the first hydrogen gas tank 10 detached from the mobile machine 20 by the hydrogen supply equipment.

[0056] It is preferable that the number of the plurality of hydrogen gas tanks 10 prepared in the preparation process be at least twice the number of the mobile machines 20 prepared in the preparation process. When multiple types of mobile machines and multiple types of hydrogen gas tanks corresponding to each of the multiple types are prepared, it is preferable that the number of hydrogen gas tanks prepared for each of the types be at least twice the number of the mobile machines.

[0057] In the installation process, only a single hydrogen supply facility may be installed within the work area, or multiple hydrogen supply facilities may be installed depending on the number of mobile machines 20 to be prepared.

[0058] The operation step preferably includes filling the first hydrogen gas tank 10 with hydrogen gas in advance, and attaching the first hydrogen gas tank 10 filled with hydrogen gas to the mobile machine 20. When a plurality of mobile machines 20 are operated, preferably, the same number of hydrogen gas tanks as the number of mobile machines 20 to be operated are filled with hydrogen gas in advance. The hydrogen gas tank 10 may be filled with a maximum fill amount of hydrogen gas, which is the maximum amount of hydrogen gas that can be filled, or may be filled with hydrogen gas less than the maximum fill amount (for example, 50% of the maximum fill amount). Pre-filling the hydrogen gas tank 10 with the amount of hydrogen gas required to start operating the mobile machine 20 enables the mobile machine 20 to be operated efficiently.

[0059] The operating step preferably includes supplying hydrogen gas to a hydrogen gas tank 10 not mounted on the mobile machine 20, for example, the second hydrogen gas tank 10, by the hydrogen supply equipment while the mobile machine 20 is operating. This allows the hydrogen gas tank 10 mounted on the mobile machine 20 to be efficiently replaced. In other words, the mobile machine 20 can be efficiently replenished with hydrogen gas, thereby improving the efficiency of continuous operation of the mobile machine 20.

[0060] In the desorption process, the first hydrogen gas tank 10 is detached from the mobile machine 20 after the hydrogen gas in the first hydrogen gas tank 10 is consumed. Therefore, it is preferable that the mobile machine system further includes a tank remaining amount indicator that notifies the operator of the mobile machine 20 of the remaining amount of hydrogen gas in the hydrogen gas tank 10 attached to the mobile machine 20. The tank remaining amount indicator may be a visual indicator, such as a display, or an audible indicator, such as a voice guide. The indicator may display the remaining amount of hydrogen gas, or may display the remaining travel time or distance predicted from the remaining amount of hydrogen gas. The specific configuration of the indicator is not limited. The indicator may be, for example, a known display, an analog display, or a digital display indicator. The tank remaining amount indicator enables the operator of the mobile machine 20 to predict when the attached hydrogen gas tank 10 should be replaced. The tank remaining amount alarm may be installed, for example, in a mobile machine operated by an operator on board, in an operating device for remotely operating a mobile machine, or in a control room that manages the operating status of an autonomously operating mobile machine (e.g., an unmanned aerial vehicle).

[0061] In the installation process, the second hydrogen gas tank 10 filled with hydrogen gas is installed in place of the first hydrogen gas tank 10 that was detached from the mobile machine 20 after the hydrogen gas in the first hydrogen gas tank 10 was consumed by operation of the mobile machine 20. In this way, replacing the used first hydrogen gas tank 10 with the second hydrogen gas tank 10 filled with hydrogen gas enables the mobile machine 20 to operate continuously.

[0062] In the supply step, hydrogen gas is supplied by the hydrogen supply equipment (e.g., one of the hydrogen supply equipment 30A and 30B) to the first hydrogen gas tank 10 detached from the mobile machine 20 in the desorption step. The supply of hydrogen gas to the first hydrogen gas tank 10 can be performed while the mobile machine 20 equipped with the second hydrogen gas tank 10 is in operation.

[0063] The operating method preferably further includes a step of supplying hydrogen gas by a hydrogen supply facility to a third hydrogen gas tank 10 selected from the plurality of hydrogen gas tanks 10 and attached to the mobile machine 20. For example, when more than twice the number of hydrogen gas tanks 10 as the number of mobile machines 20 are prepared, it is possible to fill the third hydrogen gas tank 10, which is an extra hydrogen gas tank other than the first and second hydrogen gas tanks 10, with hydrogen gas while the mobile machine 20 attached with the first hydrogen gas tank 10 is in operation or while the mobile machine 20 attached with the second hydrogen gas tank 10 is in operation. This makes it possible to improve the reliability of continuous operation of the mobile machine 20.

[0064] Charging of hydrogen gas into the hydrogen gas tank 10 detached from the mobile machine 20 and the remaining hydrogen gas tank 10 does not necessarily have to be performed while the mobile machine 20 is in operation, but may be performed during a period when the operation of the mobile machine 20 is suspended, for example, between the end of the operation and the start of operation the next day. Alternatively, the hydrogen gas may be charged both during the operation of the mobile machine 20 and during a period when the operation of the mobile machine 20 is suspended. In other words, hydrogen gas can be charged into hydrogen gas tanks 10 that are not attached to the mobile machine 20 at any time.

[0065] 2 including the hydrogen cartridge 33 preferably further includes a remaining amount monitoring unit that monitors the amount of hydrogen gas remaining in the hydrogen cartridge 33. The remaining amount monitoring unit makes it possible to easily determine when to replenish a hydrogen cartridge filled with hydrogen gas (i.e., when to replace the hydrogen cartridge), or when to switch the hydrogen cartridge 33 used among the plurality of hydrogen cartridges 33 by the selection unit 34. The remaining amount monitoring unit may include an alarm that notifies an operator of the time for replenishment, or may have a function of automatically ordering replenishment (addition) of the hydrogen cartridge 33.

[0066] The remaining amount monitoring unit may be configured to obtain information provided from the in-tank remaining amount indicator via an appropriate communication means, and monitor the remaining amount of hydrogen gas in the hydrogen gas tank 10 attached to the mobile machine 20, along with the remaining amount of hydrogen gas in the hydrogen cardle 33. This enables the replacement or switching timing to be determined more accurately. The gas remaining amount monitoring unit may further be configured to monitor the consumption rate of hydrogen gas per unit time in each of the hydrogen gas tank 10 attached to the hydrogen cardle 33 and the hydrogen gas tank 10 attached to the mobile machine 20, in order to predict the replacement or switching timing.

[0067] The remaining amount monitoring unit may be configured to predict the amount of hydrogen gas to be consumed based on the operation schedule of all the mobile machines 20. This allows the replacement or switching timing to be determined more accurately. The operation schedule includes at least one of the schedule until the end of the current operation and the schedule of operation in the future (for example, the next day).

[0068] In the above-described mobile machine system and operation method, the installation of the hydrogen supply equipment (e.g., hydrogen supply equipment 30A or hydrogen supply equipment 30B) within a predetermined work area in which the mobile machine 20 operates reduces the need to dispatch the mobile machine 20 outside the work area to replenish it with hydrogen gas, and enables the supply of hydrogen gas to mobile machines that are prohibited from operating outside the work area. Furthermore, the mobile machine 20 can be easily replenished with hydrogen gas by replacing a used hydrogen gas tank 10 with the hydrogen gas tank 10 filled with hydrogen gas by the hydrogen supply equipment, i.e., by replacing the hydrogen gas tank 10. This enables the mobile machine 20 to be operated continuously and efficiently.

[0069] The above-described embodiments do not limit the configuration of the present invention. The components of each part of the above-described embodiments may be omitted, substituted, or added based on the description in this specification and common technical knowledge, and all such omissions, substitutions, or additions should be construed as falling within the scope of the present invention.

Claims

1. A mobile machinery system comprising: a plurality of hydrogen gas tanks, each capable of storing hydrogen gas; a mobile machine that moves within a predetermined working area and includes a drive source that uses the hydrogen gas stored in each of the hydrogen gas tanks; and a hydrogen supply equipment that is installed within the working area and supplies hydrogen gas to each of the hydrogen gas tanks, wherein each of the hydrogen gas tanks can be attached and detached to the mobile machine, and the hydrogen supply equipment is configured to be able to supply hydrogen gas to both a hydrogen gas tank of the plurality of hydrogen gas tanks that has been detached from the mobile machine and a hydrogen gas tank that is attached to the mobile machine, and the hydrogen supply equipment includes a cooling unit that cools the hydrogen gas tank to which the hydrogen gas is supplied.

2. A mobile machinery system according to claim 1, wherein the cooling section includes a pipeline and is configured to supply cooling water to the hydrogen gas tank through the pipeline.

3. A mobile machinery system according to claim 2, wherein the cooling unit further includes a cooling water tank for storing cooling water, and a cooling water pump for supplying the cooling water stored in the cooling water tank to the hydrogen gas tank through the pipeline.

4. A mobile machinery system according to claim 1, wherein the hydrogen supply facility further includes a pressure reducing section that reduces the pressure of the hydrogen gas supplied to the hydrogen gas tank.

5. A mobile machinery system according to claim 1, wherein the hydrogen supply facility further includes a flow rate adjusting unit that adjusts the flow rate of hydrogen gas supplied to the hydrogen gas tank.

6. A mobile machinery system according to claim 1, wherein the hydrogen supply facility further includes a compression unit that compresses the hydrogen gas supplied to the hydrogen gas tank.

7. A mobile machinery system as set forth in claim 6, wherein the compression unit includes a compressor that operates to compress hydrogen gas supplied to the hydrogen gas tank, a return path that is arranged to allow a portion of the hydrogen gas compressed by the compressor to be returned upstream of the compressor, a pressure regulating valve that is arranged in the return path, and a pressure regulator that opens the pressure regulating valve to allow hydrogen gas to flow through the return path when the pressure of the hydrogen gas compressed by the compressor reaches or exceeds a set value.

8. A mobile machinery system according to any one of claims 1 to 7, wherein the hydrogen supply facility further includes a hydrogen cartridge for storing hydrogen gas.

9. A mobile machinery system according to any one of claims 1 to 7, wherein the hydrogen supply system further comprises a plurality of hydrogen cartridges, each containing hydrogen gas, and a selection unit that selects a hydrogen cartridge from the plurality of hydrogen cartridges to supply hydrogen gas to the hydrogen gas tank.

10. A method for operating a mobile machine that moves within a specified working area, comprising the steps of: preparing a plurality of hydrogen gas tanks, each capable of storing hydrogen gas; and the mobile machine including a power source that uses the hydrogen gas stored in each of the hydrogen gas tanks; installing hydrogen supply equipment within the working area for supplying hydrogen gas to the hydrogen gas tanks; operating the mobile machine equipped with a first hydrogen gas tank selected from the plurality of hydrogen gas tanks; detaching the first hydrogen gas tank from the mobile machine after the hydrogen gas in the first hydrogen gas tank has been consumed by operation of the mobile machine; attaching a second hydrogen gas tank selected from the plurality of hydrogen gas tanks to the mobile machine after the first hydrogen gas tank has been detached from the mobile machine; and supplying hydrogen gas to the first hydrogen gas tank detached from the mobile machine using the hydrogen supply equipment.

11. A method for operating a mobile machine as described in claim 10, further comprising the step of supplying hydrogen gas to a third hydrogen gas tank attached to said mobile machine by said hydrogen supply equipment, said third hydrogen gas tank being included in said plurality of hydrogen gas tanks and being a hydrogen gas tank separate from said first hydrogen gas tank and said second hydrogen gas tank.

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