Fuel cell unit and work machine

Abstract

A fuel cell unit support mechanism (FS) is connected to a revolving frame (20). A fuel cell stack (22) is fixed to the fuel cell unit support mechanism (FS). A hydrogen tank support mechanism (TF) is fixed to the fuel cell unit support mechanism (FS). A hydrogen tank (21) supplies hydrogen to the fuel cell stack (22). The hydrogen tank (21) is fixed to the hydrogen tank support mechanism (TF).

Description

Fuel cell unit and work machine

[0001] The present disclosure relates to a fuel cell unit and a work machine.

[0002] New energy sources that do not emit greenhouse gases such as carbon dioxide have been developed for use in work machines and the like. Fuel cells have attracted attention as such an energy source. Fuel cells generate electrical energy by chemically reacting hydrogen and oxygen in a fuel cell stack. After power generation, fuel cells only emit water, and no carbon dioxide. A work machine equipped with such a fuel cell is described, for example, in International Publication No. 2022 / 137688 (Patent Document 1).

[0003] International Publication No. 2022 / 137688

[0004] Compared to passenger cars, hydraulic excavators and other work machinery are subject to greater shocks and vibrations. This means that hydrogen system components, such as fuel cells, hydrogen tanks, and hydrogen piping, are subject to greater displacement when subjected to shock. When the relative displacement between hydrogen system components becomes too great, damage occurs to the hydrogen piping and its connections, reducing durability.

[0005] An object of the present disclosure is to provide a fuel cell unit and a work machine that have good durability.

[0006] The fuel cell unit of the present disclosure is a fuel cell unit attached to a body frame of a work machine, and includes a fuel cell unit support mechanism, a fuel cell, a first hydrogen tank support mechanism, and a first hydrogen tank group. The fuel cell unit support mechanism is connected to the body frame. The fuel cell is fixed to the fuel cell unit support mechanism. The first hydrogen tank support mechanism is fixed to the fuel cell unit support mechanism. The first hydrogen tank group is fixed to the first hydrogen tank support mechanism and includes at least one hydrogen tank that supplies hydrogen to the fuel cell.

[0007] According to the present disclosure, it is possible to realize a fuel cell unit and a work machine that have good durability.

[0008] FIG. 1 is a side view showing the configuration of a work machine having a fuel cell according to an embodiment of the present disclosure; FIG. 2 is a side view showing a first example arrangement of a fuel cell stack and a hydrogen tank in the work machine shown in FIG. 1; FIG. 3 is a rear view showing the first example arrangement of a fuel cell stack and a hydrogen tank in the work machine shown in FIG. 1; FIG. 4 is a side view showing a second example arrangement of a fuel cell stack and a hydrogen tank; FIG. 5 is a rear view showing the second example arrangement of a fuel cell stack and a hydrogen tank; FIG. 6 is a side view showing a third example arrangement of a fuel cell stack and a hydrogen tank; FIG. 7 is a rear view showing the third example arrangement of a fuel cell stack and a hydrogen tank; FIG. 8 is a side view showing a fourth example arrangement of a fuel cell stack and a hydrogen tank; FIG. 9 is a rear view showing the fourth example arrangement of a fuel cell stack and a hydrogen tank; FIG. 10 is a side view showing a fifth example arrangement of a fuel cell stack and a hydrogen tank when two hydrogen tank support mechanisms are provided; FIG. 11 is a side view showing a sixth example arrangement of a fuel cell stack and a hydrogen tank when two hydrogen tank support mechanisms are provided; FIG. 12 is a side view showing a seventh example arrangement of a fuel cell stack and a hydrogen tank when two hydrogen tank support mechanisms are provided.

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the specification and drawings, identical or corresponding components are designated by the same reference numerals, and redundant explanations will not be repeated. In addition, in the drawings, configurations may be omitted or simplified for the sake of convenience.

[0010] In the following description, the terms "up," "down," "front," "rear," "left," and "right" refer to directions relative to the operator seated in the driver's seat 14S in the driver's cab 14 shown in Figure 1.

[0011] Therefore, in the following description, the fore-aft direction X is the direction in which the boom 16 extends between the base end and the tip end in a top view. The left-right direction Y is the direction perpendicular to the fore-aft direction X in a top view. The up-down direction Z is the direction perpendicular to a plane including the fore-aft direction X and the left-right direction Y, which are perpendicular to each other.

[0012] The direction from the base end of the boom 16 to the tip end is the front, and the direction from the tip end of the boom 16 to the base end is the rear. When looking forward from the rear, the right and left sides are the right and left, respectively. In the vertical direction Z, the side with the ground is the bottom, and the side with the sky is the top. A top view refers to a perspective from which the work machine 100 is viewed from above and below. A side view refers to a perspective from which the revolving unit 13 is viewed from the left-right direction Y. A rear view refers to a perspective from which the revolving unit 13 is viewed from behind to the front.

[0013] <Configuration of Work Machine> Hereinafter, a work machine according to the present disclosure will be described using FIG. 1 , taking a shovel equipped with a fuel cell as an example.

[0014] The work machine of the present disclosure is not limited to a shovel, but may be a bulldozer, wheel loader, motor grader, or the like equipped with a fuel cell.

[0015] Fig. 1 is a side view that schematically shows the configuration of a work machine according to one embodiment of the present disclosure. As shown in Fig. 1, the work machine 100 according to this embodiment is, for example, a shovel that has a fuel cell unit FCU. The fuel cell included in the fuel cell unit FCU generates electrical energy by causing a chemical reaction between hydrogen and oxygen.

[0016] The work machine 100 has a fuel cell stack 22 as a fuel cell. The fuel cell stack 22 is a stack of multiple fuel cell units connected in series. The work machine 100 has, for example, two fuel cell stacks 22, but the number of fuel cell stacks 22 mounted on the work machine 100 is not limited to two and may be one, or may be three or more.

[0017] The work machine 100 has hydrogen tanks 21 for supplying hydrogen to the fuel cell stack 22. The work machine 100 has, for example, four hydrogen tanks 21, but the number of hydrogen tanks 21 mounted on the work machine 100 is not limited to four and may be one, or may be two, three, five or more.

[0018] The work machine 100 has a main body 11 and a hydraulically operated work implement 12. The main body 11 has a revolving body 13 and a traveling body 15.

[0019] The running body 15 has a pair of left and right crawler tracks 15Cr and a traveling motor 15M. The work machine 100 can travel by rotation of the crawler tracks 15Cr. The traveling motor 15M is provided as a drive source for the running body 15.

[0020] The rotating body 13 is disposed on and supported by the running body 15. The rotating body 13 can be rotated relative to the running body 15 about a rotation axis RX by a rotation motor (not shown). The rotation axis RX is an imaginary straight line that serves as the rotation center of the rotating body 13. The rotation motor may be hydraulically driven or electrically driven.

[0021] The rotating body 13 has a driver's cab 14. A driver's seat 14S where an operator sits is provided inside the driver's cab 14. The operator sits in the driver's seat 14S and can operate the work implement 12, rotate the rotating body 13 relative to the traveling body 15, and travel the work machine 100 using the traveling body 15.

[0022] The work implement 12 is supported by the revolving unit 13. The work implement 12 has a boom 16, an arm 17, and a bucket 18. The work implement 12 further has a boom cylinder 19a, an arm cylinder 19b, and a bucket cylinder 19c.

[0023] The boom 16 is rotatably connected to the main body 11. Specifically, the base end of the boom 16 is rotatably connected to the revolving unit 13 with a boom foot pin BF as a fulcrum. The arm 17 is rotatably connected to the boom 16. Specifically, the base end of the arm 17 is rotatably connected to the tip of the boom 16 with a boom top pin BT as a fulcrum. The bucket 18 is rotatably connected to the arm 17. Specifically, the base end of the bucket 18 is rotatably connected to the tip of the arm 17 with an arm top pin AT as a fulcrum.

[0024] The rotating body 13 has an exterior panel OP that surrounds a machinery room. A hydrogen tank 21, a fuel cell stack 22, a storage battery 27, a cooling unit CU (FIG. 3), etc. are arranged in the machinery room of the rotating body 13. The hydrogen tank 21, the fuel cell stack 22, the storage battery 27, the cooling unit CU, etc. are covered by the exterior panel OP.

[0025] Although the above describes a configuration in which the driver's seat 14S is located inside the driver's cab 14, the driver's seat 14S may be exposed to the outside without the driver's cab 14. The work machine 100 may also not have a driver's cab 14 and operate automatically without a human. The work machine 100 may also not have a driver's cab 14 and be remotely operated by a remote controller.

[0026] <Arrangement of Fuel Cell Stack and Hydrogen Tank> (First Arrangement Example) Next, a first arrangement example of the fuel cell stack 22 and hydrogen tank 21 in the work machine 100 shown in FIG. 1 will be described with reference to FIGS. 2 and 3. FIG.

[0027] Figures 2 and 3 are a side view and a rear view, respectively, showing a first example of the arrangement of the fuel cell stack and hydrogen tank in the work machine shown in Figure 1. As shown in Figure 2, the fuel cell unit FCU has a hydrogen tank group 21A, a fuel cell stack 22, a fuel cell unit support mechanism FS, a hydrogen tank support mechanism TF, and a damping mechanism DM. The fuel cell unit FCU is attached to a swivel frame (body frame) 20 of the work machine 100.

[0028] A fuel cell unit support mechanism FS is connected to the revolving frame 20 via a damping mechanism DM and the like. The damping mechanism DM supports the fuel cell unit support mechanism FS relative to the revolving frame 20.

[0029] The damping mechanism DM has the function of damping vibrations. The damping mechanism DM may be, for example, a liquid-filled mount or rubber. A liquid-filled mount as the damping mechanism DM is configured to obtain a large damping force by the pressure loss caused when the enclosed viscous liquid is squeezed as it passes through a minute gap. The viscous liquid used in a liquid-filled mount is, for example, silicone oil.

[0030] The fuel cell unit support structure FS has a lower plate (mount portion) UP, an upper plate (ceiling portion) TP, and pillar members (side frame portions) CM. The lower plate UP is connected to the revolving frame 20 via a damping mechanism DM and other components. The ceiling portion TP is disposed above the fuel cell (fuel cell stack 22) and is configured to protect the upper portion of the fuel cell and to secure other components to the upper portion. The mount portion UP is disposed below the fuel cell and is configured to protect the lower portion of the fuel cell and to secure other components to the upper portion. Each of the ceiling portion TP and the mount portion UP is not limited to a plate and may be a frame.

[0031] The fuel cell stacks 22 are arranged on the revolving frame 20. For example, each of the two fuel cell stacks 22 is fixed to the fuel cell unit support structure FS by, for example, bolting or welding. This restrains each of the two fuel cell stacks 22 so that it cannot move relative to the fuel cell unit support structure FS. Therefore, each of the two fuel cell stacks 22 and the fuel cell unit support structure FS constitute the same vibration system, in which the vibration pattern relative to the revolving frame 20 is the same.

[0032] Specifically, for example, each of the two fuel cell stacks 22 is disposed on a lower plate UP of the fuel cell unit support mechanism FS. By being fixed to the lower plate UP, each of the two fuel cell stacks 22 constitutes the same vibration system as the lower plate UP.

[0033] The two fuel cell stacks 22 are arranged side by side in the front-rear direction X, for example, and extend substantially parallel to each other in the left-right direction Y (FIG. 3). An upper plate TP is arranged on top of the fuel cell stack 22 to protect the upper part of the fuel cell stack 22. The upper plate TP is supported by a lower plate UP via pillar members CM extending in the up-down direction Z. The pillar members CM connect the lower plate UP and the upper plate TP.

[0034] The lower plate UP and the column members CM are fixed to each other by bolting, welding, etc. The column members CM and the upper plate TP are also fixed to each other by bolting, welding, etc. This restrains the lower plate UP, the column members CM, and the upper plate TP so that they cannot move relative to each other. The lower plate UP, the column members CM, and the upper plate TP constitute the same vibration system in which the vibration pattern relative to the revolving frame 20 is the same.

[0035] A hydrogen tank support mechanism TF is fixed to the fuel cell unit support mechanism FS by, for example, bolting or welding. Specifically, the hydrogen tank support mechanism TF is placed on and fixed to the upper plate TP of the fuel cell unit support mechanism FS. This restrains the hydrogen tank support mechanism TF so that it cannot move relative to the fuel cell unit support mechanism FS. Therefore, the hydrogen tank support mechanism TF and the fuel cell unit support mechanism FS constitute the same vibration system, in which the vibration pattern relative to the rotating frame 20 is the same.

[0036] The hydrogen tank group 21A is disposed on top of the fuel cell stack 22. The hydrogen tank group 21A is fixed to the hydrogen tank support mechanism TF, for example, by a belt or the like. This restrains the hydrogen tank group 21A so that it cannot move relative to the hydrogen tank support mechanism TF. Furthermore, as described above, the hydrogen tank support mechanism TF is restrained so that it cannot move relative to the fuel cell unit support mechanism FS. Therefore, the hydrogen tank group 21A is restrained via the hydrogen tank support mechanism TF so that it cannot move relative to the fuel cell unit support mechanism FS.

[0037] As a result of the above, both the hydrogen tank group 21A and the two fuel cell stacks 22 are restrained so that they cannot move relative to the fuel cell unit support mechanism FS, and they form the same vibration system in which the vibration pattern relative to the rotating frame 20 is the same.

[0038] The hydrogen tank group 21A includes at least one hydrogen tank 21. The hydrogen tank group 21A may be made up of one hydrogen tank 21 or a plurality of hydrogen tanks 21.

[0039] For example, four hydrogen tanks 21 are fixed to the hydrogen tank support mechanism TF as a hydrogen tank group 21A. The four hydrogen tanks 21 are arranged in two rows and two columns in a side view. That is, the four hydrogen tanks 21 are arranged so that two are lined up in the front-to-rear direction X and two are lined up in the up-down direction Z in a side view. Each of the four hydrogen tanks 21 extends in the left-to-right direction Y so as to be approximately parallel to one another.

[0040] A pressure reducer 23 is attached to the hydrogen tank support mechanism TF. The pressure reducer 23 has a pressure reducing valve and functions to reduce the pressure of the high-pressure hydrogen gas supplied from the hydrogen tanks 21 to a level that can be used in the fuel cell stack 22, which is a power generation device. The pressure reducer 23 is disposed, for example, in front of the arrangement area AR of the four hydrogen tanks 21. The arrangement position of the pressure reducer 23 is not limited to being in front of the arrangement area AR, but may also be behind or to the side of the arrangement area AR.

[0041] The hydrogen tank 21 and the pressure reducer 23 are connected by a tank hose TH (Figure 3). High-pressure hydrogen gas in the hydrogen tank 21 is supplied to the pressure reducer 23 through this tank hose TH. An on-off valve 24 is disposed between the hydrogen tank 21 and the tank hose TH. The on-off valve 24 opens and closes to control the start and stop of the supply of high-pressure hydrogen gas from the hydrogen tank 21 to the pressure reducer 23.

[0042] The pressure reducer 23 and the fuel cell stack 22 are connected by a stack hose SH. Hydrogen gas decompressed by the pressure reducer 23 is supplied to the fuel cell stack 22 through this stack hose SH.

[0043] The connection P1 between the fuel cell stack 22 and the stack hose SH, the connection P2 between the hydrogen tank 21 and the tank hose TH, the connection P3 between the stack hose and the pressure reducer 23, and the connection P3 between the tank hose TH and the pressure reducer 23 are locations where hydrogen gas is likely to leak. These connection parts P1, P2, and P3 are located on the same side of each other in the left-right direction Y. For example, connection part P1 may be located at the left end of the fuel cell stack 22, connection part P2 may be located at the left end of the hydrogen tank 21, and connection part P3 may be located at the left end of the pressure reducer 23. Alternatively, connection part P1 may be located at the right end of the fuel cell stack 22, connection part P2 may be located at the right end of the hydrogen tank 21, and connection part P3 may be located at the right end of the pressure reducer 23.

[0044] 3, the work machine 100 has a cooling unit CU. The cooling unit CU has a radiator 25 and an electric fan (cooling fan) 26.

[0045] The radiator 25 is a device for dissipating heat from a cooling medium (coolant, for example, water) that cools the fuel cell stack 22. The radiator 25 is, for example, a heat exchanger. The radiator 25 is disposed, for example, to the side of the fuel cell stack 22, for example, on the left side of the fuel cell stack 22. The radiator 25 may also be disposed, for example, on the right side of the fuel cell stack 22, or on the front or rear side of the fuel cell stack 22.

[0046] The electric fan 26 blows air onto the radiator 25 to dissipate heat emitted from the radiator 25. The electric fan 26 is disposed, for example, between the radiator 25 and the fuel cell stack 22.

[0047] For example, each of the four hydrogen tanks 21 is arranged so that the longitudinal direction of the hydrogen tank 21 is aligned with the left-right direction Y of the work machine 100. Each of the two hydrogen tanks 21 lined up in the front-to-rear direction X is arranged so that the longitudinal direction of the hydrogen tank 21 is located in a plane that includes the left-to-right direction Y and the front-to-rear direction X of the work machine 100. Each of the two hydrogen tanks 21 lined up in the up-to-down direction Z is arranged so that the longitudinal direction of the hydrogen tank 21 is located in a plane that includes the left-to-right direction Y and the up-to-down direction Z of the work machine 100.

[0048] The on-off valves 24 of each of the four hydrogen tanks 21 are arranged on the same longitudinal side of the hydrogen tank 21. The on-off valves 24 of each of the four hydrogen tanks 21 are arranged, for example, on the left side in the longitudinal direction of the hydrogen tank 21. The on-off valves 24 of each of the four hydrogen tanks 21 are arranged at the end of the hydrogen tank 21 that is closer to the cooling unit CU.

[0049] First Arrangement Example 1 has the configuration described above. (Second Arrangement Example) Figures 4 and 5 are side and rear views, respectively, showing a second arrangement example of a fuel cell stack and a hydrogen tank. As shown in Figure 4, the second arrangement example differs from the first arrangement example in the fixing location of the hydrogen tank support mechanism TF, the arrangement of the hydrogen tank 21, the configuration of the fuel cell unit support mechanism FS, and the arrangement of the fuel cell stack 22.

[0050] In the second arrangement example, the hydrogen tank support mechanism TF is fixed to the lower plate UP of the fuel cell unit support mechanism FS. For example, four hydrogen tanks 21 are fixed to the hydrogen tank support mechanism TF as a hydrogen tank group 21A. The four hydrogen tanks 21 are arranged, for example, in a single vertical row aligned in the vertical direction Z. The four hydrogen tanks 21 are arranged, for example, behind the fuel cell stack 22.

[0051] The fuel cell unit support structure FS has a lower plate UP, a center plate CP, an upper plate TP, and pillar members CM. The lower plate UP is connected to the revolving frame 20 via a damping mechanism DM or the like. The center plate CP is disposed on the lower plate UP. The upper plate TP is disposed on the center plate CP. Pillar members CM are fixed to each of the lower plate UP and the center plate CP, for example, by bolting or welding. Pillar members CM are fixed to each of the center plate CP and the upper plate TP, for example, by bolting or welding. This restrains the lower plate UP, center plate CP, and upper plate TP so that they cannot move relative to one another.

[0052] For example, two fuel cell stacks 22 are stacked in the vertical direction Z. The lower fuel cell stack 22 is fixed to a lower plate UP, and the upper fuel cell stack 22 is fixed to a center plate CP. The center plate CP protects the upper part of the lower fuel cell stack 22 and also protects the lower part of the upper fuel cell stack 22. The center plate CP is not limited to a plate, and may be a frame.

[0053] The four hydrogen tanks 21 and the two fuel cell stacks 22 are restrained so that they cannot move relative to the fuel cell unit support mechanism FS, and form the same vibration system in which the vibration pattern relative to the rotating frame 20 is the same.

[0054] 5 , each of the four hydrogen tanks 21 extends in the left-right direction Y so as to be substantially parallel to one another. Each of the four hydrogen tanks 21 is arranged so that the longitudinal direction of the hydrogen tank 21 is along the left-right direction Y of the work machine 100. Each of the four hydrogen tanks 21 is arranged so that the longitudinal direction of the hydrogen tank 21 is located within a plane that includes the left-right direction Y and the up-down direction Z of the work machine 100.

[0055] The on-off valves 24 of each of the four hydrogen tanks 21 are arranged on the same side in the longitudinal direction of the hydrogen tank 21. The on-off valves 24 of each of the four hydrogen tanks 21 are arranged, for example, on the left side in the longitudinal direction of the hydrogen tank 21.

[0056] Since the configuration of the second arrangement example other than the above is almost the same as the configuration of the first arrangement example, the same components as or corresponding components to the first arrangement example in the second arrangement example are given the same symbols, and redundant explanations will not be repeated.

[0057] 6 and 7 are side and rear views, respectively, showing a third example of the arrangement of the fuel cell stack and the hydrogen tank. As shown in Fig. 6, the third example of the arrangement differs from the second example of the arrangement in the arrangement of the hydrogen tank 21.

[0058] In the third arrangement example, the four hydrogen tanks 21 forming the hydrogen tank group 21A are arranged in two rows and two columns in a side view. That is, the four hydrogen tanks 21 are arranged so that two are lined up in the front-to-rear direction X and two are lined up in the up-down direction Z in a side view.

[0059] As shown in Figure 7, each of the four hydrogen tanks 21 extends in the left-right direction Y so as to be approximately parallel to one another. Each of the four hydrogen tanks 21 is arranged so that the longitudinal direction of the hydrogen tank 21 is along the left-right direction Y of the work machine 100. Each of the two hydrogen tanks 21 lined up in the front-rear direction X is arranged so that the longitudinal direction of the hydrogen tank 21 is located in a plane that includes the left-right direction Y and the front-rear direction X of the work machine 100. Each of the two hydrogen tanks 21 lined up in the up-down direction Z is arranged so that the longitudinal direction of the hydrogen tank 21 is located in a plane that includes the left-right direction Y and the up-down direction Z of the work machine 100.

[0060] The on-off valves 24 of each of the four hydrogen tanks 21 are arranged on the same side in the longitudinal direction of the hydrogen tank 21. The on-off valves 24 of each of the four hydrogen tanks 21 are arranged, for example, on the left side in the longitudinal direction of the hydrogen tank 21.

[0061] Since the configuration of the third arrangement example other than the above is almost the same as the configuration of the second arrangement example, the same components as or corresponding components to the second arrangement example in the third arrangement example are given the same symbols, and redundant explanations will not be repeated.

[0062] 8 and 9 are side and rear views, respectively, showing a fourth arrangement example of the fuel cell stack and hydrogen tanks. As shown in Fig. 8, the fourth arrangement example differs from the second arrangement example in the arrangement of the hydrogen tanks 21. In the fourth arrangement example, each of the four hydrogen tanks 21 constituting the hydrogen tank group 21A is arranged so that the longitudinal direction of the hydrogen tank 21 is aligned with the up-down direction Z.

[0063] 9, the four hydrogen tanks 21 are arranged side by side in the left-right direction Y so as to form a horizontal row when viewed from the rear. Each of the four hydrogen tanks 21 is arranged so that the longitudinal direction of the four hydrogen tanks 21 is located within a plane that includes the left-right direction Y and the up-down direction Z of the work machine 100.

[0064] The on-off valves 24 of each of the four hydrogen tanks 21 are arranged on the same side in the longitudinal direction of the hydrogen tank 21. The on-off valves 24 of each of the four hydrogen tanks 21 are arranged, for example, on the upper side in the longitudinal direction of the hydrogen tank 21.

[0065] Since the configuration of the fourth arrangement example other than the above is almost the same as the configuration of the second arrangement example, the same components as or corresponding components to the second arrangement example in the fourth arrangement example are given the same symbols, and redundant explanations will not be repeated.

[0066] In the first to fourth arrangement examples above, the fuel cell unit FCU has one hydrogen tank support mechanism TF, but the fuel cell unit FCU may have multiple hydrogen tank support mechanisms TF. Configurations in which the fuel cell unit FCU has, for example, two hydrogen tank support mechanisms TF will be described below as fifth to seventh arrangement examples.

[0067] 10 is a side view showing a fifth arrangement example of a fuel cell stack and a hydrogen tank when two hydrogen tank support mechanisms are provided. As shown in Fig. 10, the fuel cell unit FCU has a first hydrogen tank support mechanism TF1 and a second hydrogen tank support mechanism TF2.

[0068] For example, four hydrogen tanks 21 are fixed to the first hydrogen tank support mechanism TF1 as a first hydrogen tank group 21A. The four hydrogen tanks 21 as the first hydrogen tank group 21A are arranged in two rows and two columns in a side view. That is, the four hydrogen tanks 21 are arranged so that two are lined up in the front-to-rear direction X and two are lined up in the up-down direction Z in a side view. Each of the four hydrogen tanks 21 extends in the left-to-right direction Y so as to be approximately parallel to one another.

[0069] For example, four hydrogen tanks 21 are fixed to the second hydrogen tank support mechanism TF2 as a second hydrogen tank group 21B. The four hydrogen tanks 21 as the second hydrogen tank group 21B are arranged in two rows and two columns in a side view. That is, the four hydrogen tanks 21 are arranged so that two are lined up in the front-to-rear direction X and two are lined up in the up-down direction Z in a side view. Each of the four hydrogen tanks 21 extends in the left-to-right direction Y so as to be approximately parallel to one another.

[0070] The first hydrogen tank support mechanism TF1 and the second hydrogen tank support mechanism TF2 are each fixed to the upper plate TP of the fuel cell unit support mechanism FS. This restrains the fuel cell stack 22, first hydrogen tank group 21A, and second hydrogen tank group 21B from moving relative to the fuel cell unit support mechanism FS, and they form the same vibration system in which the vibration pattern relative to the revolving frame 20 is the same.

[0071] 11 is a side view showing a sixth arrangement example of a fuel cell stack and hydrogen tanks when two hydrogen tank support mechanisms are provided. As shown in FIG. 11, the sixth arrangement example differs from the fifth arrangement example in that the second hydrogen tank support mechanism TF2 is fixed to the lower plate UP of the fuel cell unit support mechanism FS.

[0072] 12 is a side view showing a seventh arrangement example of a fuel cell stack and hydrogen tanks when two hydrogen tank support mechanisms are provided. As shown in FIG. 12, the seventh arrangement example differs from the sixth arrangement example in that the four hydrogen tanks 21 of the second hydrogen tank group 21B fixed to the second hydrogen tank support mechanism TF2 are aligned in a row in the vertical direction Z.

[0073] In the first to seventh arrangement examples described above, the hydrogen tank 21 is cylindrical, but the hydrogen tank 21 may also be prismatic. Furthermore, in the fifth to seventh arrangement examples described above, when one of the first hydrogen tank support mechanism TF1 and the second hydrogen tank support mechanism TF2 is fixed to the fuel cell unit support mechanism FS, the other of the first hydrogen tank support mechanism TF1 and the second hydrogen tank support mechanism TF2 does not have to be directly fixed to the fuel cell unit support mechanism FS as long as it is fixed to the other one.

[0074] <Effects> Next, the effects of the present disclosure will be described.

[0075] 2, in this embodiment, the fuel cell stack 22 is fixed to the fuel cell unit support mechanism FS. Furthermore, a hydrogen tank support mechanism TF is fixed to the fuel cell unit support mechanism FS, and the hydrogen tank 21 is fixed to the hydrogen tank support mechanism TF. As a result, both the fuel cell stack 22 and the hydrogen tank 21 are restrained so that they cannot move relative to the fuel cell unit support mechanism FS, and they form the same vibration system with the same vibration pattern relative to the rotating frame 20. This reduces the amount of relative displacement of the fuel cell stack 22 and the hydrogen tank 21 when the work machine 100 vibrates due to normal traveling, excavation, or swinging, or when the work machine 100 is subjected to an impact, making the hydrogen piping (tank hose TH, stack hose SH) and their connections P1, P2, P3 less likely to be damaged and improving durability.

[0076] 2, in this embodiment, the damping mechanism DM supports the fuel cell unit support mechanism FS relative to the revolving frame 20. As a result, vibrations transmitted from the revolving frame 20 to the fuel cell unit support mechanism FS are damped by the damping mechanism DM. This further reduces the amount of relative displacement between the fuel cell stack 22 and the hydrogen tank 21 when the work machine 100 receives an impact, further improving durability.

[0077] 2, in this embodiment, the hydrogen tank support mechanism TF is fixed to the upper plate (ceiling portion) TP of the fuel cell unit support mechanism FS. This increases the installation height of the hydrogen tank 21, improving access to the opening / closing valve 24 of the hydrogen tank 21 and facilitating maintenance of the hydrogen tank 21. Furthermore, because the installation height of the hydrogen tank 21 is increased, it becomes easier to install and remove the hydrogen tank 21.

[0078] 4, 6, and 8, in this embodiment, the hydrogen tank support mechanism TF is fixed to the lower plate (mounting portion) UP of the fuel cell unit support mechanism FS. This allows for easy access to the fuel cell stack 22, facilitating maintenance of the fuel cell stack 22.

[0079] 3, 5, 7, and 9, in this embodiment, the on-off valves 24 of the multiple hydrogen tanks 21 fixed to the hydrogen tank support mechanism TF are arranged on the same longitudinal side of the hydrogen tanks 21. This shortens the hydrogen piping (tank hose TH, stack hose SH) and simplifies the hydrogen piping arrangement, making it possible to reduce the load on the hydrogen piping and its connections.

[0080] 10 to 12, this embodiment is provided with a first hydrogen tank support mechanism TF1 and a second hydrogen tank support mechanism TF2 that support different hydrogen tanks 21. This allows the hydrogen tank support mechanisms TF1 and TF2 to be detached separately, making maintenance easier.

[0081] 3, 5, and 7, according to this embodiment, the hydrogen tank 21 is arranged so that its longitudinal direction is aligned with the left-right direction Y of the work machine 100. This makes it less likely for the hydrogen tank 21 to be displaced when the rotating unit 13 sways in the rotation direction, for example. Furthermore, because the dimension of the work machine 100 in the fore-aft direction X can be reduced, the rotation radius of the rotating unit 13 can be kept small.

[0082] 3, 5 and 7, in this embodiment, the hydrogen tank 21 is positioned so that its longitudinal direction is located within a plane that includes the left-right direction Y and the front-rear direction X of the work machine 100. This reduces the installation height of the hydrogen tank 21 in the up-down direction Z, improving the rearward visibility of the operator operating the work machine 100.

[0083] 9 , in this embodiment, the hydrogen tank 21 is positioned so that its longitudinal direction is aligned with the vertical direction Z of the work machine 100, and the on-off valve 24 of the hydrogen tank 21 is positioned above the hydrogen tank 21. This allows good access to the on-off valve 24, making maintenance of the hydrogen tank 21 easy.

[0084] 4, 6, and 8, in this embodiment, the hydrogen tank 21 is disposed behind the fuel cell stack 22. Normally, hydraulic devices such as a swing hydraulic motor are disposed in front of the fuel cell stack 22. Therefore, by disposing the hydrogen tank 21 behind the fuel cell stack 22, it is possible to place the hydrogen tank 21 in a location with a low ambient temperature.

[0085] <Additional Notes> The above-described embodiment includes the following technical ideas.

[0086] (Supplementary Note 1) A fuel cell unit attached to a body frame of a work machine, comprising: a fuel cell unit support mechanism connected to the body frame; a fuel cell fixed to the fuel cell unit support mechanism; a first hydrogen tank support mechanism fixed to the fuel cell unit support mechanism; and a first hydrogen tank group fixed to the first hydrogen tank support mechanism and including at least one hydrogen tank that supplies hydrogen to the fuel cell.

[0087] (Supplementary Note 2) The fuel cell unit according to Supplementary Note 1, further comprising a damping mechanism, wherein the fuel cell unit support mechanism and the vehicle body frame are connected via the damping mechanism.

[0088] (Appendix 3) The fuel cell unit described in Appendix 2, wherein the fuel cell unit support mechanism has a mount portion connected to the vehicle body frame via the damping mechanism, a ceiling portion that protects the upper part of the fuel cell, and a side frame portion that connects the mount portion and the ceiling portion, and the first hydrogen tank support mechanism is fixed to the ceiling portion.

[0089] (Appendix 4) The fuel cell unit described in Appendix 2, wherein the fuel cell unit support mechanism has a mount portion connected to the vehicle body frame via the damping mechanism, a ceiling portion that protects the upper part of the fuel cell, and a side frame portion that connects the mount portion and the ceiling portion, and the first hydrogen tank support mechanism is fixed to the mount portion.

[0090] (Appendix 5) A fuel cell unit described in any one of Appendices 1 to 4, wherein a plurality of hydrogen tanks included in the first hydrogen tank group are fixed to the first hydrogen tank support mechanism, and the opening and closing valves of each of the plurality of hydrogen tanks fixed to the first hydrogen tank support mechanism are arranged on the same side of the hydrogen tanks in the longitudinal direction.

[0091] (Appendix 6) A fuel cell unit described in any one of Appendices 1 to 5, further comprising: a second hydrogen tank group including at least one hydrogen tank different from the first hydrogen tank group; and a second hydrogen tank support mechanism to which the second hydrogen tank group is fixed, wherein the second hydrogen tank support mechanism is fixed to the fuel cell unit support mechanism or the first hydrogen tank support mechanism.

[0092] (Appendix 7) A fuel cell unit as described in Appendix 6, wherein a plurality of hydrogen tanks included in the second hydrogen tank group are fixed to the second hydrogen tank support mechanism, and the opening and closing valves of each of the plurality of hydrogen tanks fixed to the second hydrogen tank support mechanism are arranged on the same side of the hydrogen tanks in the longitudinal direction.

[0093] (Supplementary Note 8) The fuel cell unit according to any one of Supplementary Notes 1 to 7, wherein the longitudinal direction of the hydrogen tanks included in the first hydrogen tank group is aligned with the left-right direction of the work machine.

[0094] (Supplementary Note 9) A fuel cell unit as described in any one of Supplementary Notes 1 to 7, wherein the longitudinal direction of the hydrogen tanks included in the first hydrogen tank group is located within a plane including the left-right direction and the front-rear direction of the work machine.

[0095] (Appendix 10) A fuel cell unit described in any one of Appendices 1 to 7, wherein the longitudinal direction of the hydrogen tanks included in the first hydrogen tank group is aligned with the vertical direction of the work machine, and the opening and closing valves of the hydrogen tanks included in the first hydrogen tank group are located above the hydrogen tanks.

[0096] (Supplementary Note 11) The fuel cell unit according to any one of Supplementary Note 1 to Supplementary Note 10, wherein the first hydrogen tank group is disposed behind the fuel cell.

[0097] (Supplementary Note 12) A work machine equipped with the fuel cell unit according to any one of Supplementary Note 1 to Supplementary Note 11.

[0098] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0099] DESCRIPTION OF SYMBOLS 11 Main body, 12 Work machine, 13 Swing body, 14 Driver's cab, 14S Driver's seat, 15 Running body, 15Cr Track, 15M Travel motor, 16 Boom, 17 Arm, 18 Bucket, 19a Boom cylinder, 19b Arm cylinder, 19c Bucket cylinder, 20 Swing frame, 21 Hydrogen tank, 21A, 21B Hydrogen tank group, 22 Fuel cell stack, 23 Pressure reducer, 24 On-off valve, 25 Radiator, 26 Electric fan, 100 Work machine, AR Placement area, AT Arm top pin, BF Boom foot pin, BT Boom top pin, CM Pillar member, CU Cooling unit, DM Damping mechanism, FCU Fuel cell unit, FS Fuel cell unit support mechanism, OP Exterior panel, P1, P2, P3 Connection part, RX Swing axis, SH Stack hose, TF Hydrogen tank support mechanism, TF1 first hydrogen tank support mechanism, TF2 second hydrogen tank support mechanism, TH tank hose, TP upper plate, UP lower plate.

Claims

1. A fuel cell unit attached to a body frame of a working machine, comprising: a fuel cell unit support mechanism connected to the body frame; a fuel cell fixed to the fuel cell unit support mechanism; a first hydrogen tank support mechanism fixed to the fuel cell unit support mechanism; and a first hydrogen tank group fixed to the first hydrogen tank support mechanism and including at least one hydrogen tank which supplies hydrogen to the fuel cell.

2. The fuel cell unit according to claim 1, further comprising a damping mechanism, said fuel cell unit support mechanism and said vehicle body frame being connected via said damping mechanism.

3. A fuel cell unit as described in claim 2, wherein the fuel cell unit support mechanism has a mount portion connected to the vehicle frame via the damping mechanism, a ceiling portion protecting an upper portion of the fuel cell, and a side frame portion connecting the mount portion and the ceiling portion, and the first hydrogen tank support mechanism is fixed to the ceiling portion.

4. A fuel cell unit as described in claim 2, wherein the fuel cell unit support mechanism has a mount portion connected to the vehicle body frame via the damping mechanism, a ceiling portion protecting an upper portion of the fuel cell, and a side frame portion connecting the mount portion and the ceiling portion, and the first hydrogen tank support mechanism is fixed to the mount portion.

5. A fuel cell unit as described in claim 1, wherein a plurality of hydrogen tanks included in the first hydrogen tank group are fixed to the first hydrogen tank support mechanism, and the opening and closing valves of each of the plurality of hydrogen tanks fixed to the first hydrogen tank support mechanism are arranged on the same side of the hydrogen tanks in the longitudinal direction.

6. A fuel cell unit as described in claim 1, further comprising: a second hydrogen tank group including at least one hydrogen tank different from the first hydrogen tank group; and a second hydrogen tank support mechanism to which the second hydrogen tank group is fixed, wherein the second hydrogen tank support mechanism is fixed to the fuel cell unit support mechanism or the first hydrogen tank support mechanism.

7. A fuel cell unit as described in claim 6, wherein a plurality of hydrogen tanks included in the second hydrogen tank group are fixed to the second hydrogen tank support mechanism, and the opening and closing valves of each of the plurality of hydrogen tanks fixed to the second hydrogen tank support mechanism are arranged on the same side of the hydrogen tanks in the longitudinal direction.

8. The fuel cell unit according to claim 1, wherein the longitudinal direction of the hydrogen tanks included in said first hydrogen tank group is aligned with the left-right direction of said work machine.

9. A fuel cell unit as set forth in claim 1, wherein the longitudinal direction of the hydrogen tanks included in said first hydrogen tank group is located within a plane including the left-right direction and the front-rear direction of said work machine.

10. A fuel cell unit as described in claim 1, wherein the longitudinal direction of the hydrogen tanks included in the first hydrogen tank group is aligned along the vertical direction of the work machine, and the opening and closing valves of the hydrogen tanks included in the first hydrogen tank group are positioned above the hydrogen tanks.

11. The fuel cell unit according to claim 1, wherein said first group of hydrogen tanks is disposed rearward of said fuel cell.

12. A work machine equipped with the fuel cell unit according to claim 1.

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