Work machine

Abstract

To improve safety in the event of a hydrogen leak and suppress temperature increases around a hydrogen tank.SOLUTION: A work machine (100) comprises a hydrogen tank (31) storing hydrogen, a heat exchanger (33) exchanging heat with cooling air (CA), electronic equipment (34) for operating the work machine (100), and a machine room (14). The hydrogen tank (31) is disposed in the machine room (14) above the electronic equipment (34) and upstream of the heat exchanger (33) in the flow direction of the cooling air (CA).SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a work machine, such as a hydraulic excavator, that is equipped with a hydrogen tank. [Background technology]

[0002] Patent Document 1 discloses a hydrogen tank storage case designed to exhaust leaked hydrogen. Patent Document 2 discloses a fuel cell vehicle designed to improve safety against hydrogen leaks. The technologies of Patent Documents 1 and 2 are both intended for use in automobiles such as trucks. Patent Document 3 discloses a work machine such as a hydraulic excavator equipped with a fuel cell.

[0003] Generally, a work machine such as a hydraulic excavator includes a lower traveling body, an upper rotating body rotatably supported on the lower traveling body, a working implement including a boom rotatably supported on the upper rotating body, hydraulic equipment, and electronic equipment for operating the work machine. The hydraulic equipment includes various devices for the traveling operation of the lower traveling body, the rotating operation of the upper rotating body, and the rotating operation of the working implement. A cab is disposed in front of a rotating frame of the upper rotating body, a counterweight is disposed in the rear of the rotating frame, and a machine room is formed between the cab and the counterweight. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2021-187163 A [Patent Document 2] Patent Publication No. 2022-73237 [Patent Document 3] International Publication No. 2022 / 137688 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, in a work machine, many devices such as a cab, counterweight, and hydraulic equipment must be arranged on a revolving frame, so the space in the machine room is inevitably limited. When hydrogen-related devices including a hydrogen tank, a heat exchanger for cooling the devices, and electronic devices for operating the work machine are arranged in the machine room, which is a limited space, the techniques of Patent Documents 1 and 2 cannot be directly adopted as safety measures in the event of a hydrogen leak. In addition, when both the heat exchanger and the hydrogen tank are arranged in the machine room, a problem arises in that the temperature around the hydrogen tank is likely to rise. Patent Document 3 does not disclose any means for solving these problems.

[0006] An object of the present disclosure is to provide a work machine that can improve safety in the event of a hydrogen leak and can suppress a rise in temperature around the hydrogen tank. [Means for solving the problem]

[0007] The work machine of the first aspect comprises a hydrogen tank for storing hydrogen, a heat exchanger for exchanging heat with cooling air, electronic equipment for operating the work machine, and a machinery room, wherein the hydrogen tank is positioned in the machinery room above the electronic equipment and upstream of the heat exchanger in the flow direction of the cooling air.

[0008] In this work machine, even if hydrogen gas leaks from the hydrogen tank or its vicinity, the hydrogen gas moves upward from the hydrogen tank or its vicinity in the machine room, and is therefore prevented from reaching electronic devices located below the hydrogen tank. This improves safety in the event of a hydrogen leak. In addition, the hydrogen tank, which is located upstream of the heat exchanger in the machine room, is supplied with cooling air before passing through the heat exchanger, i.e., cooling air before its temperature rises due to heat exchange in the heat exchanger, and therefore a temperature rise around the hydrogen tank is suppressed. Suppressing the temperature rise around the hydrogen tank contributes to suppressing a temperature rise in the hydrogen tank when it is filled with hydrogen. Furthermore, if the hydrogen tank is, for example, a plastic tank, suppressing the temperature rise around the hydrogen tank also contributes to suppressing deterioration of the plastic tank.

[0009] A second aspect is preferably the work machine according to the first aspect, further comprising the following feature. That is, in the work machine according to the second aspect, the machine room is defined by a wall portion having an air intake port for drawing air outside the machine room into the inside of the machine room as the cooling air, and an exhaust port for discharging the cooling air inside the machine room to the outside of the machine room, and the work machine is preferably further provided with a cooling fan for forming a flow of the cooling air. In this second aspect, a flow of cooling air from the air intake port to the exhaust port can be effectively formed in the machine room. In the work machine according to the second aspect, the cooling fan may be disposed, for example, between the exhaust port and the heat exchanger, or may be disposed between the exhaust port and the heat exchanger and adjacent to the exhaust port.

[0010] The third aspect is preferably the work machine according to the second aspect further comprising the following feature. That is, in the work machine according to the third aspect, it is preferable that at least a part of the intake port is formed at a height position that is horizontally aligned with the hydrogen tank or at a position higher than the hydrogen tank. In this third aspect, even if hydrogen gas leaks from the hydrogen tank or its vicinity, the hydrogen gas is likely to be discharged to the outside of the machine room through the intake port that is formed at the same height position as the hydrogen tank or at a position higher than the hydrogen tank. This further improves safety in the event of a hydrogen leak.

[0011] A fourth aspect is preferably a work machine according to the second or third aspect, further comprising the following feature. That is, in the work machine according to the fourth aspect, it is preferable that at least a part of the exhaust port is formed at a height position that is horizontally aligned with the hydrogen tank or at a position higher than the hydrogen tank. In this fourth aspect, even if hydrogen gas leaks from the hydrogen tank or its vicinity, the hydrogen gas is likely to be discharged to the outside of the machine room through an exhaust port formed at the same height position as the hydrogen tank or at a position higher than the hydrogen tank. This further improves safety in the event of a hydrogen leak.

[0012] A fifth aspect is preferably the working machine according to any one of the second to fourth aspects, further comprising the following feature. That is, the working machine according to the fifth aspect further comprises a temperature detector that detects the temperature of the hydrogen tank or a temperature related thereto, and a controller, and it is preferable that the controller performs control to increase the number of revolutions of the cooling fan when the temperature detected by the temperature detector reaches or exceeds a preset specified value. In this fifth aspect, when the temperature detected by the temperature detector reaches or exceeds the specified value, the number of revolutions of the cooling fan is automatically increased by control by the controller, so that a rise in temperature around the hydrogen tank is effectively suppressed. The temperature detector may, for example, be one that detects the temperature of the hydrogen tank, one that detects the temperature around the hydrogen tank (ambient temperature), one that detects the temperature at the hydrogen outlet of the hydrogen tank, one that detects the temperature of hydrogen in the hydrogen tank, or one that detects the temperature of a pipe connecting the hydrogen tank and a fuel cell device.

[0013] A sixth aspect is preferably a working machine according to any one of the second to fifth aspects, further comprising the following feature. That is, the working machine according to the sixth aspect preferably comprises a hydrogen detector that detects hydrogen in the machine room, and a controller, and the controller preferably controls the cooling fan to increase the rotation speed when the hydrogen detector detects hydrogen. In this sixth aspect, when hydrogen gas is detected in the machine room, the rotation speed of the cooling fan is automatically increased under control of the controller, promoting ventilation of the machine room. This further improves safety in the event of a hydrogen leak.

[0014] A seventh aspect is preferably the work machine according to any one of the first to sixth aspects, further comprising the following feature. That is, the work machine according to the seventh aspect preferably further comprises a partition for preventing the cooling air that has passed through the heat exchanger from mixing with the cooling air before passing through the heat exchanger in the machine room. In this seventh aspect, the partition prevents the cooling air whose temperature has increased by passing through the heat exchanger from mixing with the cooling air before passing through the heat exchanger, so that a rise in temperature around the hydrogen tank is more effectively prevented. In the work machine according to the seventh aspect, it is more preferable that the partition is disposed so as to follow at least a portion of the periphery of the heat exchanger, and it is even more preferable that the partition is disposed so as to follow the entire periphery of the heat exchanger.

[0015] An eighth aspect may further include the following feature in the work machine according to any one of the first to sixth aspects. That is, the work machine according to the eighth aspect may further include a fuel cell device to which hydrogen is supplied from the hydrogen tank, and the fuel cell device may be disposed below the hydrogen tank and in a position overlapping the hydrogen tank when viewed from above. In this eighth aspect, even if hydrogen gas leaks from the fuel cell device, the leaked hydrogen gas rises toward the hydrogen tank located above the fuel cell device, so that the hydrogen gas can be prevented from diffusing into an area where other devices are disposed. Also, in this eighth aspect, the fuel cell device is disposed in a position overlapping the hydrogen tank when viewed from above, so that the length of the piping connecting the hydrogen tank and the fuel cell device can be reduced.

[0016] A ninth aspect may be the work machine according to any one of the first to seventh aspects, further comprising the following feature. That is, the work machine according to the ninth aspect may further comprise a fuel cell device to which hydrogen is supplied from the hydrogen tank, and hydrogen-related equipment including the hydrogen tank and the fuel cell device may be disposed above the electronic equipment. In this ninth aspect, even if hydrogen gas leaks from the hydrogen-related equipment, the hydrogen gas moves upward from the hydrogen-related equipment in the machine room, and is therefore prevented from reaching the electronic equipment disposed below the hydrogen-related equipment. This improves safety in the event of a hydrogen leak.

[0017] A tenth aspect is preferably the working machine according to the ninth aspect, further comprising the following features. That is, the working machine according to the tenth aspect further comprises a boom and a revolving frame, the revolving frame having a frame body and a rising structure standing from the frame body and extending forward and backward, the rising structure including a boom mounting part to which the base end of the boom is attached and a rear part located rearward of the boom mounting part and lower in height than the boom mounting part, and the hydrogen-related equipment is preferably disposed in a position higher than the rear part of the rising structure and in a position overlapping with the rear part when viewed from above. In this tenth aspect, the hydrogen-related equipment, which is large and heavy, is disposed in a position higher than the rear part of the rising structure and in a position overlapping with the rear part when viewed from above, thereby making it possible to position the center of gravity of the entire working machine as far back and as low as possible.

[0018] An eleventh aspect is preferably the work machine according to the tenth aspect further comprising the following feature. That is, in the work machine according to the eleventh aspect, it is preferable that the electronic device is arranged on at least one of the right and left of the rear part of the standing solid body. In this eleventh aspect, by arranging the electronic device in a space formed on at least one of the right and left of the rear part of the standing solid body, it is possible to improve safety in the event of a hydrogen leak and to improve the mounting efficiency of the parts that make up the work machine.

[0019] A twelfth aspect is preferably a working machine according to the tenth or eleventh aspect further comprising the following feature: That is, in the working machine according to the twelfth aspect, the rising solid body includes left and right rising plates that rise from the frame body and extend forward and backward, the left and right rising plates are preferably arranged at a distance from each other in the left-right direction, and the electronic device is arranged between the left and right rising plates. In this twelfth aspect, by arranging the electronic device in the space formed between the left and right rising plates, it is possible to improve safety in the event of a hydrogen leak and to improve the mounting efficiency of the parts that make up the working machine.

[0020] A thirteenth aspect is preferably a working machine according to any one of the ninth to twelfth aspects, further comprising the following feature: That is, the working machine according to the thirteenth aspect preferably further comprises a partition wall arranged between the hydrogen-related equipment and the electronic equipment in the machine room. In this thirteenth aspect, the area in which the hydrogen-related equipment is arranged and the area in which the electronic equipment is arranged are separated by a partition wall, thereby further improving safety in the event of a hydrogen leak.

[0021] A fourteenth aspect is preferably the work machine according to the thirteenth aspect further comprising the following feature. That is, in the work machine according to the fourteenth aspect, it is preferable that the hydrogen-related equipment is modularized on the partition. In this fourteenth aspect, it is possible to improve the workability when arranging the hydrogen tank and fuel cell device included in the hydrogen-related equipment on the partition.

[0022] A fifteenth aspect is preferably the working machine according to the thirteenth or fourteenth aspect further comprising the following feature. That is, in the working machine according to the fifteenth aspect, the electronic device is a first electronic device, the partition is a first partition, and the working machine may further comprise a second electronic device that is different from the first electronic device and is arranged in a position horizontally aligned with the hydrogen-related device, and a second partition arranged in the machine room between the hydrogen-related device and the second electronic device. Even if it is necessary to arrange a second electronic device in addition to the first electronic device in the machine room and to arrange the second electronic device in a position horizontally aligned with the hydrogen-related device, in the fifteenth aspect, the area in which the hydrogen-related device is arranged and the area in which the second electronic device is arranged are separated by the second partition, so that safety in the event of a hydrogen leak can be ensured.

[0023] A work machine according to a sixteenth aspect includes a hydrogen tank for storing hydrogen, a heat exchanger for exchanging heat with cooling air, electronic equipment for operating the work machine, a machine room, and a partition wall arranged in the machine room between the hydrogen tank and the electronic equipment, and the hydrogen tank is arranged in the machine room upstream of the heat exchanger in the flow direction of the cooling air. In the work machine according to the sixteenth aspect, the partition wall separates the area in which the hydrogen tank is arranged from the area in which the electronic equipment is arranged, so that even if hydrogen gas leaks from the hydrogen tank or its vicinity, the leaked hydrogen gas is prevented from reaching the electronic equipment in the machine room. This improves safety in the event of a hydrogen leak. In addition, the hydrogen tank arranged upstream of the heat exchanger in the machine room is supplied with cooling air before passing through the heat exchanger, i.e., cooling air before its temperature rises due to heat exchange in the heat exchanger, so that a temperature rise around the hydrogen tank is suppressed. Suppressing the temperature rise around the hydrogen tank contributes to suppressing the temperature rise of the hydrogen tank when filling the hydrogen tank with hydrogen. Furthermore, if the hydrogen tank is, for example, a plastic tank, suppressing the temperature rise around the hydrogen tank also contributes to suppressing deterioration of the plastic tank. Effect of the Invention

[0024] According to the present disclosure, a work machine is provided that can improve safety in the event of a hydrogen leak and suppress a rise in temperature around the hydrogen tank. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a left side view showing a work machine according to an embodiment of the present disclosure. [Diagram 2] FIG. [Diagram 3] FIG. 2 is a perspective view of an upper rotating body of the work machine as viewed diagonally from the rear left. [Figure 4] FIG. 2 is a plan view showing a revolving frame and a cab of the upper revolving body. [Diagram 5] FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, showing the inside of a machine room of a work machine according to a first embodiment of the present disclosure. [Figure 6] 6 is a partially cutaway left side view of the working machine, including a cross section of a wall portion defining the machine room taken along line VI-VI in FIG. 5. [Figure 7] FIG. 4 is a cross-sectional view showing the inside of the machine room. [Figure 8] 4 is a cross-sectional view showing the inside of the machine room, illustrating a state in which a hydrogen filling device is connected to the hydrogen filling port. FIG. [Figure 9] FIG. 11 is a side view showing an arrangement of electronic devices and hydrogen-related devices arranged on a rotating frame of a work machine according to a second embodiment of the present disclosure. [Figure 10] 1. FIG. 4 is a cross-sectional view taken along line AA in FIG. 1, showing the inside of a machine room of a work machine according to a second embodiment. [Figure 11] FIG. 11 is a side view showing the arrangement of electronic devices and hydrogen-related devices arranged on a revolving frame of a work machine according to a first modified example of the second embodiment. [Figure 12] FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, showing the inside of a machine room of a working machine according to a first modified example of the second embodiment. [Figure 13]1. FIG. 4 is a diagram showing the inside of a machine room of a work machine according to a first modified example of the second embodiment, and is a cross-sectional view taken along line BB in FIG. [Figure 14] 1. FIG. 4 is a diagram showing the inside of a machine room of a work machine according to a second modification of the second embodiment, and is a cross-sectional view taken along line AA in FIG. [Figure 15] 1. FIG. 4 is a diagram showing the inside of a machine room of a work machine according to a second modification of the second embodiment, and is a cross-sectional view taken along line BB in FIG. [Figure 16] 1. FIG. 4 is a cross-sectional view taken along line AA in FIG. 1, showing the inside of a machine room of a work machine according to a third embodiment. [Figure 17] 1. FIG. 4 is a cross-sectional view taken along line BB in FIG. 1, showing the inside of a machine room of a work machine according to a modified example of the third embodiment. [Figure 18] 1. FIG. 4 is a cross-sectional view taken along line AA in FIG. 1, showing the inside of a work machine according to another modified example. [Figure 19] 19 is a perspective view of an upper rotating body of a work machine according to the modified example shown in FIG. 18, as viewed diagonally from the front right. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] An embodiment of the present disclosure will be described with reference to the drawings. Fig. 1 is a left side view showing a work machine 100 according to an embodiment of the present disclosure. Fig. 2 is a right side view showing the work machine 100. Fig. 3 is a perspective view of the upper rotating body 2 of the work machine 100 as seen diagonally from the left rear. Fig. 4 is a plan view showing the rotating frame 20 and cab 11 of the upper rotating body 2.

[0027] The work machine 100 includes a lower travelling body 1 including a travelling device, an upper rotating body 2 supported on the lower travelling body 1 so as to be rotatable relative to the lower travelling body 1 about a vertically extending rotation axis Z, and a work device 3 supported on the upper rotating body 2. The work machine 100 according to this embodiment is a hydraulic excavator, but the work machine in this disclosure is not limited to hydraulic excavators and may be other work machines such as a crane or a bulldozer. The travelling device may be, for example, a crawler-type travelling device or a travelling device having tires.

[0028] The upper rotating body 2 includes a rotating frame 20, a cab 11 supported by the rotating frame 20, a counterweight 12, and a plurality of covers.

[0029] The revolving frame 20 is a member supported by the lower traveling body 1 so as to be revolvable. The revolving frame 20 includes a frame main body 21 and a riser 22. The frame main body 21 has an upper surface large enough to accommodate the cab 11 and the wall portion 13. The cab 11 is disposed at the left front portion of the frame main body 21, and the counterweight 12 is disposed at the rear portion of the frame main body 21 or rearward of the frame main body 21. A driver's seat, operating levers, operating pedals, etc. are disposed in the cab 11. A machine room 14 is formed behind the cab 11.

[0030] In this embodiment, the machinery room 14 is formed behind the cab 11 and in front of the counterweight 12, and is defined by a wall 13. The wall 13 may have any shape that can define the machinery room 14, and the specific shape is not particularly limited. The wall 13 may have, for example, a box shape. Note that if the weight of the equipment placed in the machinery room 14 is large, the counterweight 12 can be omitted.

[0031] The rising body 22 supports the boom 4 so that it can be raised and lowered. As shown in FIG. 1, the rising body 22 has a shape that rises from the frame main body 21 and extends forward and backward as shown by the dashed line in FIG. 1. The rising body 22 includes a boom mounting part 22A (front part) to which the base end part 4A of the boom 4 shown by the dashed line in FIG. 1 is attached, and a rear part 22B. The rear part 22B is located rearward of the boom mounting part 22A and is lower in height than the boom mounting part 22A. In this embodiment, as shown in FIG. 1 and FIG. 4, the rising body 22 includes left and right rising plates 23, 23 that face each other at a distance from each other on the left and right. Each of the left and right rising plates 23, 23 is a plate-shaped member that rises from the frame main body 21 and extends forward and backward from the front end to the rear end. The boom mounting part 22A is composed of a right boom mounting part of the right rising plate 23 and a left boom mounting part of the left rising plate 23.

[0032] At least a portion of the multiple covers define a machine chamber 14. The multiple covers include a front cover 13F located on the front side of the machine chamber 14, a rear cover 13B located on the rear side of the machine chamber 14, a left cover 13L located on the left side of the machine chamber 14, a right cover 13R located on the right side of the machine chamber 14, and an upper cover 13U located on the upper side of the machine chamber 14. In this embodiment, the wall portion 13 that defines the machine chamber 14 includes the front cover 13F, the rear cover 13B, the left cover 13L, the right cover 13R, and the upper cover 13U.

[0033] The multiple covers further include a weight cover 13W that covers the counterweight 12, and an equipment cover 13H that defines an equipment storage room 15 that has an equipment storage space for storing various equipment inside. In this embodiment, the weight cover 13W is located behind the rear cover 13B, and the equipment cover 13H is disposed at the right front part of the frame body 21 and located in front of the front cover 13F. The wall part 13 may include one or both of the weight cover 13W and the equipment cover 13H. The weight cover 13W may constitute the counterweight itself. The equipment storage space inside the equipment storage room 15 may be a space that constitutes a part of the machine room 14, or may be a space separate from the machine room 14.

[0034] The working device 3 includes a boom 4 that is attached to the upper rotating body 2 so as to be able to rise and fall, an arm 5 that is attached to the boom 4 so as to be able to rotate, and a tip attachment 6 that is attached to the arm 5 so as to be able to rotate. In this embodiment, the tip attachment 6 is a bucket, but the tip attachment may be another tip attachment such as a grapple, a fork, a crusher, or the like.

[0035] The hydraulic equipment includes a hydraulic pump 81, an unillustrated control valve, and an unillustrated hydraulic oil tank. A part or all of the hydraulic equipment may be disposed inside the machine room 14, or may be disposed outside the machine room 14. A part or all of the hydraulic equipment may be disposed in an equipment accommodating space inside the equipment accommodating chamber 15, or may be disposed outside the equipment accommodating chamber 15. In this embodiment, the hydraulic pump 81 is disposed in the machine room 14, and the control valve is disposed in the equipment accommodating space inside the equipment accommodating chamber 15. The hydraulic pump 81 is driven by an electric motor 34A described later to discharge hydraulic oil.

[0036] The work machine 100 includes a plurality of actuators. Each of the plurality of actuators operates by receiving a supply of hydraulic oil discharged from a hydraulic pump 81. The plurality of actuators include a boom cylinder 7 for raising and lowering the boom 4, an arm cylinder 8 for rotating the arm 5, a tip attachment cylinder 9 for rotating the tip attachment 6, a swing motor (not shown) for rotating the upper swing body 2 relative to the lower traveling body 1, and a traveling motor (not shown) included in the traveling device of the lower traveling body 1.

[0037] The control valve opens and closes in response to a lever or pedal operation given by an operator to an operating device (not shown) so that hydraulic oil is supplied from a hydraulic pump 81 to an actuator corresponding to that operation.

[0038] [First embodiment] Fig. 5 is a diagram showing the inside of the machine room 14 of the work machine 100 according to the first embodiment, and is a cross-sectional view taken along line AA in Fig. 1. Fig. 5 shows various devices disposed in the machine room 14, and also indicates with arrows the flow of cooling air CA in the machine room 14.

[0039] The work machine 100 according to the first embodiment comprises a hydrogen tank 31 that stores hydrogen, a fuel cell device 32 to which hydrogen (hydrogen gas) is supplied from the hydrogen tank 31, a heat exchanger 33 that exchanges heat with cooling air CA, electronic equipment 34 for operating the work machine 100, and a wall section 13 that defines a machine room 14. The hydrogen tank 31 is disposed above the electronic equipment 34 in the machine room 14, and upstream of the heat exchanger 33 in the flow direction of the cooling air CA.

[0040] The hydrogen tank 31 is a resin tank. An example of a resin tank is a type 4 resin tank. The type 4 resin tank is a resin container with carbon fiber reinforced plastic wrapped around the outside, and is highly strong. However, the hydrogen tank 31 is not limited to a type 4 resin tank, and may be another type of resin tank or a tank made of material other than resin.

[0041] High-pressure hydrogen gas stored in the hydrogen tank 31 is supplied to a pressure reducing valve 42 via a high-pressure hydrogen pipe 41, and is reduced in pressure at the pressure reducing valve 42. The reduced-pressure hydrogen gas is supplied to the fuel cell device 32 via a medium-pressure hydrogen pipe 43.

[0042] The fuel cell device 32 is configured to be able to supply electric power to the electric motor 34A. The fuel cell device 32 includes a fuel cell that generates electric power by electrochemically reacting hydrogen supplied from the hydrogen tank 31 with oxygen (for example, oxygen contained in the air introduced from the air inlet 16). The fuel cell is configured, for example, by a fuel cell stack including a plurality of cells.

[0043] The heat exchanger 33 cools the fuel cell of the fuel cell device 32. In this embodiment, the heat exchanger 33 is configured to perform heat exchange between the cooling water circulating between the fuel cell device 32 and the heat exchanger 33 and the cooling air CA. The heat exchanger 33 may be, for example, a radiator or another type of heat exchanger.

[0044] The electronic device 34 includes an electric motor 34A and an inverter 34B. The electronic device 34 may further include at least one of a converter, a battery, a compressor, a water pump, and a heater (not shown). The battery may be charged by power generated by the fuel cell device 32. In this embodiment, the electric motor 34A and the inverter 34B are disposed upstream of the fuel cell device 32 in the flow direction of the cooling air CA. However, at least one of the electric motor 34A and the inverter 34B may be disposed downstream of the fuel cell device 32 in the flow direction of the cooling air CA, and specifically, may be disposed in a region between the fuel cell device 32 and the heat exchanger 33.

[0045] The electric motor 34A is a drive source that drives the hydraulic pump 81. The electric motor 34A is operated by receiving a supply of electric power from the fuel cell device 32. The electric motor 34A is configured as, for example, a three-phase motor. The electric motor 34A may be operated by receiving a supply of electric power output from a battery.

[0046] The inverter 34B is connected to the fuel cell device 32 via a high-voltage wiring 47. The inverter 34B is interposed between the fuel cell device 32 and the electric motor 34A, and converts DC current supplied from at least one of the fuel cell device 32 and the battery into three-phase AC current and supplies it to the electric motor 34A. The inverter 34B adjusts the rotation speed of the electric motor 34A.

[0047] The converter steps down the high voltage output from the fuel cell device 32 or the battery and supplies it to a fan motor 35B of a cooling fan 35 described below. The compressor is, for example, a device that compresses vaporized refrigerant, and is included in an air conditioning device for adjusting the temperature inside the cab 11. The water pump circulates cooling water between the fuel cell device 32 and the heat exchanger 33 through water piping 46. The heater may include at least one of an electric heater constituting a heating device that heats the inside of the cab 11, an electric heater for preheating a battery, and an electric heater for preheating hydraulic oil.

[0048] In this working machine 100, even if hydrogen gas leaks from the hydrogen tank 31 or its vicinity (for example, a hydrogen filling port described later), hydrogen gas has a specific gravity of less than 1 based on air (i.e., it is lighter than air), so in the machine room 14, it moves upward from the hydrogen tank 31 or its vicinity and is prevented from reaching the electronic device 34 arranged below the hydrogen tank 31. This improves safety in the event of a hydrogen leak. In addition, the hydrogen tank 31 arranged upstream of the heat exchanger 33 in the machine room 14 is supplied with cooling air CA before passing through the heat exchanger 33, i.e., cooling air CA before its temperature increases due to heat exchange in the heat exchanger 33. The temperature around the hydrogen tank 31 may rise due to heat generated by the operation of devices arranged inside the machine room 14, such as the fuel cell device 32, the electronic device 34, and the hydraulic pump 81. In this embodiment, however, the cooling air CA before passing through the heat exchanger 33 is also supplied to the vicinity of these devices, so that the temperature rise around the hydrogen tank 31 is more effectively suppressed. When hydrogen is filled into the hydrogen tank 31, the temperature of the hydrogen tank rises as the pressure of the hydrogen gas in the hydrogen tank 31 increases, but since cooling air CA is supplied around the hydrogen tank 31, the temperature rise around the hydrogen tank 31 is suppressed. Hydrogen filling will be described later. Furthermore, suppressing the temperature rise around the hydrogen tank 31 also contributes to suppressing deterioration of the resin tank. When hydrogen is supplied from the hydrogen tank 31 to the fuel cell device 32, the temperature of the hydrogen tank 31 drops as the hydrogen gas in the hydrogen tank 31 is depressurized, and the temperature of the cooling air CA that has passed around the hydrogen tank 31 drops. Therefore, in this embodiment, the heat exchanger 33, which is arranged downstream of the hydrogen tank 31 in the machine room 14, is supplied with cooling air CA whose temperature has been reduced by passing around the hydrogen tank 31, so that the heat exchange efficiency (cooling efficiency) of the heat exchanger 33 can be improved.

[0049] The wall portion 13 has an intake port 16 and an exhaust port 17. The intake port 16 is an opening for drawing air outside the machine chamber 14 into the inside of the machine chamber 14 as cooling air CA. The exhaust port 17 is an opening for discharging the cooling air CA inside the machine chamber 14 to the outside of the machine chamber 14. In this embodiment, the intake port 16 is formed in the right cover 13R of the wall portion 13, and the exhaust port 17 is formed in the left cover 13L of the wall portion 13. However, the part of the wall portion 13 where the intake port 16 is formed is not limited to the right cover 13R, and the part where the exhaust port 17 is formed is not limited to the left cover 13L. Specifically, for example, the intake port 16 may be formed in the left cover 13L, the front cover 13F, the rear cover 13B, or the upper cover 13U. Also, exhaust port 17 may be formed in right cover 13R, front cover 13F, rear cover 13B, or upper cover 13U. Note that intake port 16 and exhaust port 17 are preferably formed in portions of wall portion 13 that face each other in the horizontal direction.

[0050] The work machine 100 is equipped with a cooling fan 35 that forms a flow of cooling air CA. The cooling fan 35 can effectively form a flow of cooling air CA from the intake port 16 to the exhaust port 17 in the machine room 14. In this embodiment, the cooling air CA flows from right to left in the machine room 14 as shown by the arrow in FIG. 5. The cooling fan 35 includes an impeller 35A including a plurality of blades arranged along the outer periphery of a rotating shaft, a fan motor 35B that drives the impeller 35A, and a shroud 35C that is arranged to surround the outer periphery of the impeller 35A. The shroud 35C is arranged with a gap in the radial direction relative to the impeller 35A. The cooling fan 35 is operated by power being supplied from, for example, the fuel cell device 32 or the battery.

[0051] In this embodiment, the cooling fan 35 is disposed between the exhaust port 17 and the heat exchanger 33. Specifically, the cooling fan 35 is disposed between the exhaust port 17 and the heat exchanger 33 and at a position adjacent to the exhaust port 17.

[0052] 5, part of the intake port 16 is formed at a height position that is aligned horizontally with the hydrogen tank 31. In this case, even if hydrogen gas leaks from the hydrogen tank 31 or its vicinity (for example, a hydrogen filling port) when the cooling fan 35 is not operating, the hydrogen gas is likely to be discharged to the outside of the machine room 14 through the intake port 16 formed at the same height position as the hydrogen tank 31. This further improves safety in the event of a hydrogen leak. Note that part of the intake port 16 may be formed at a position higher than the hydrogen tank 31.

[0053] Furthermore, a portion of exhaust port 17 is formed at a height position that is aligned horizontally with hydrogen tank 31. In this case, even if hydrogen gas leaks from hydrogen tank 31 or its vicinity (for example, a hydrogen filling port, etc.), the hydrogen gas is likely to be discharged to the outside of machine room 14 through exhaust port 17, which is formed at the same height position as hydrogen tank 31, regardless of whether cooling fan 35 is operating or not. This further improves safety in the event of a hydrogen leak. Note that a portion of exhaust port 17 may be formed at a position higher than hydrogen tank 31.

[0054] In this embodiment, a part (part of the upper side) of the intake port 16 is formed at a height position so as to be aligned horizontally with the hydrogen tank 31, and another part (part of the lower side) of the intake port 16 is formed at a height position so as to be aligned horizontally with the fuel cell device 32. Also, a part (part of the upper side) of the exhaust port 17 is formed at a height position so as to be aligned horizontally with the hydrogen tank 31, and another part (part of the lower side) of the exhaust port 17 is formed at a height position so as to be aligned horizontally with the fuel cell device 32. Also, in this embodiment, the entire area of ​​the exhaust port 17 is formed at a height position so as to be aligned horizontally with the heat exchanger 33. However, a part of the exhaust port 17 may be formed at a position shifted upward with respect to the heat exchanger 33, or may be formed at a position shifted downward with respect to the heat exchanger 33.

[0055] The fuel cell device 32 is disposed in the machine room 14 at a position lower than the hydrogen tank 31 and at a position overlapping with the hydrogen tank 31 when viewed from the top-bottom direction. In this case, the fuel cell device 32 can be disposed efficiently by utilizing the space below the hydrogen tank 31 inside the machine room 14, which has a limited size. Furthermore, even if hydrogen gas leaks from the fuel cell device 32, the leaked hydrogen gas rises toward the hydrogen tank 31 located above the fuel cell device 32, so that the diffusion of hydrogen gas into areas where other devices are disposed can be suppressed. Furthermore, by disposing the fuel cell device 32 at a position overlapping with the hydrogen tank 31 when viewed from the top-bottom direction, the length of the medium-pressure hydrogen piping 43 connecting the hydrogen tank 31 and the fuel cell device 32 can be reduced.

[0056] In the specific example shown in Fig. 5, the fuel cell device 32 is disposed directly below the hydrogen tank 31 in the machine room 14. This makes it possible for hydrogen gas leaking from the fuel cell device 32 to rise more reliably toward the hydrogen tank 31, and also makes it possible to further reduce the length of the medium-pressure hydrogen piping 43. Furthermore, in the specific example shown in Fig. 5, the pressure reducing valve 42 is disposed at a position offset in a predetermined direction (to the right in Fig. 5) with respect to the hydrogen tank 31, and the portion of the fuel cell device 32 to which the medium-pressure hydrogen piping 43 is connected is the side of the fuel cell device 32 that faces the predetermined direction (the right side in Fig. 5). This makes it possible to further reduce the length of the medium-pressure hydrogen piping 43.

[0057] In this embodiment, the work machine 100 includes a plurality of hydrogen tanks 31 and a support frame 60 that supports them. The plurality of hydrogen tanks 31 include a first hydrogen tank 31 and a second hydrogen tank 31 disposed directly above the first hydrogen tank 31. The support frame 60 includes a first upper frame 61 and a plurality of leg frames 62 that extend downward from the first upper frame 61 and support the first upper frame 61. The first upper frame 61 supports the first hydrogen tank 31 directly above the fuel cell device 32. The support frame 60 further includes a second upper frame 63 that is disposed higher than the first upper frame 61. The second upper frame 63 supports the second hydrogen tank 31 directly above the fuel cell device 32 and the first hydrogen tank 31. The second upper frame 63 may be supported by the wall portion 13, may be supported by the first upper frame 61, or may be supported by the plurality of leg frames 62.

[0058] As shown in FIG. 5, each of the first hydrogen tank 31 and the second hydrogen tank 31 has a shape extending in one direction (longitudinal direction), and is arranged so that this longitudinal direction is aligned with the direction of the flow of the cooling air CA. In the specific example shown in FIG. 5, each hydrogen tank 31 is arranged so that its longitudinal direction faces the left-right direction. In addition, the first hydrogen tank 31 and the second hydrogen tank 31 are arranged with a gap between them above and below. Such an arrangement of the first hydrogen tank 31 and the second hydrogen tank 31 can suppress an increase in the resistance of the flow of the cooling air CA and suppress a decrease in the heat exchange efficiency (cooling efficiency) of the heat exchanger 33. In addition, the multiple hydrogen tanks 31 arranged in the machine room 14 may include not only the first hydrogen tank 31 and the second hydrogen tank 31 arranged vertically, but also a hydrogen tank (not shown) arranged in front or behind the first hydrogen tank 31, and may further include a hydrogen tank (not shown) arranged in front or behind the second hydrogen tank 31. In this case, the hydrogen tank 31 is efficiently mounted inside the machine room 14, which is a limited space.

[0059] It is preferable that each of the first upper frame 61, the multiple leg frames 62, and the second upper frame 63 of the support frame 60 can stably support the hydrogen tank 31 and is not likely to provide resistance to the flow of the cooling air CA. That is, it is preferable that each of the multiple leg frames 62 is a member that is not likely to provide resistance to the flow of the cooling air CA (e.g., a rod-shaped member). Also, it is preferable that each of the first upper frame 61 and the second upper frame 63 is a member that is not likely to provide resistance to the flow of the cooling air CA from one side to the other of the area where the hydrogen tank 31 is arranged and the area where the fuel cell device 32 is arranged (e.g., a rod-shaped member, punching metal, etc.), rather than a member that is likely to provide resistance to the flow of the cooling air CA from one side to the other of the area where the hydrogen tank 31 is arranged and the area where the fuel cell device 32 is arranged (e.g., a plate-shaped member).

[0060] 6 is a partially cutaway left side view of the working machine 100, including a cross section of the wall portion 13 defining the machine room 14 taken along line VI-VI in FIG. 5. As shown in FIGS. 5 and 6, the working machine 100 is provided with a partition 18 for preventing the cooling air CA that has passed through the heat exchanger 33 from mixing with the cooling air CA before passing through the heat exchanger 33 in the machine room 14. In this case, in the machine room 14, an upstream space that is a space upstream of the heat exchanger 33 in the flow of the cooling air CA and a downstream space that is a space downstream of the heat exchanger 33 in the flow of the cooling air CA are separated by the heat exchanger 33 and the partition 18. This prevents the cooling air CA that has passed through the heat exchanger 33 and increased in temperature from mixing with the cooling air CA before passing through the heat exchanger 33, so that the temperature rise around the hydrogen tank 31 is more effectively suppressed.

[0061] The partition 18 is arranged, for example, along at least a part of the periphery of the heat exchanger 33. In the specific example shown in FIG. 6, the partition 18 includes an upper partition 18A arranged along the upper edge 33U of the heat exchanger 33, a front partition 18B arranged along the front edge 33F of the heat exchanger 33, and a rear partition 18C arranged along the rear edge 33B of the heat exchanger 33. The upper partition 18A extends forward and backward along the upper edge 33U of the heat exchanger 33, and closes the gap between the upper edge 33U of the heat exchanger 33 and the upper cover 13U of the wall portion 13. The front partition 18B extends vertically along the front edge 33F of the heat exchanger 33, and closes the gap between the front edge 33F of the heat exchanger 33 and the front cover 13F of the wall portion 13. The rear partition 18C extends vertically along the rear edge 33B of the heat exchanger 33 and closes the gap between the rear edge 33B of the heat exchanger 33 and the rear cover 13B of the wall portion 13.

[0062] The partition 18 may be disposed along the entire circumference of the heat exchanger 33. In this case, the partition 18 may include a lower partition 18D disposed along the lower edge of the heat exchanger 33. Note that the partition 18 does not necessarily have to be disposed along the heat exchanger 33, as long as it has a shape and is disposed so as to separate the upstream space and the downstream space.

[0063] The partition 18 may be disposed so as to follow at least a portion of the periphery of the shroud 35C. Specifically, for example, the partition 18 may be disposed such that the upper partition 18A is disposed along the upper end portion of the shroud 35C, the front partition 18B is disposed along the front end portion of the shroud 35C, and the rear partition 18C is disposed along the rear end portion of the shroud 35C. In this embodiment, the partition 18 and the shroud 35C prevent the cooling air CA, whose temperature has increased by passing through the heat exchanger 33, from mixing with the cooling air CA before passing through the heat exchanger 33, so that the temperature rise around the hydrogen tank 31 is more effectively suppressed. The partitions 18 may include both those disposed around the heat exchanger 33 and those disposed around the shroud 35C.

[0064] The work machine 100 is equipped with a plurality of sensors and a controller 70 to which the results of detection by these sensors are input. Figure 7 is a cross-sectional view showing the inside of the machine room 14, and shows the plurality of sensors and the controller 70.

[0065] The multiple sensors include a hydrogen tank ambient temperature sensor 51, a hydrogen gas temperature sensor 52, a hydrogen gas sensor 53, and a water temperature sensor 54.

[0066] Hydrogen tank ambient temperature sensor 51 detects the temperature of the atmosphere in the vicinity of hydrogen tank 31 and inputs the detection result to controller 70. Hydrogen gas temperature sensor 52 detects the temperature at the gas outlet of hydrogen tank 31 and inputs the detection result to controller 70. Hydrogen gas temperature sensor 52 may detect the temperature of a member that constitutes the gas outlet, or may detect the temperature of the hydrogen itself exiting from the gas outlet. Hydrogen tank ambient temperature sensor 51 is one example of a temperature detector in the present disclosure. Moreover, hydrogen gas temperature sensor 52 is another example of a temperature detector in the present disclosure.

[0067] The temperature detector may be a sensor that detects the temperature of the hydrogen tank 31 (for example, the temperature of the side surface of the hydrogen tank 31). The temperature detector may be, for example, one that detects the temperature of hydrogen inside the hydrogen tank 31, or one that detects the temperature of a pipe (for example, a medium-pressure hydrogen pipe 43) that connects the hydrogen tank 31 and the fuel cell device 32.

[0068] The hydrogen gas sensor 53 detects hydrogen gas in the machinery room 14. The hydrogen gas sensor 53 is preferably disposed in a location in the machinery room 14 where hydrogen gas is likely to accumulate, for example, at the upper part of the machinery room 14, and more preferably at the top part of the machinery room 14. The multiple sensors may include multiple hydrogen gas sensors 53. The multiple hydrogen gas sensors 53 are preferably disposed at positions spaced apart from each other in the machinery room 14. The hydrogen gas sensor 53 is an example of a hydrogen detector in the present disclosure.

[0069] The water temperature sensor 54 detects the temperature of the cooling water circulating between the fuel cell device 32 and the heat exchanger 33 or a temperature correlated thereto, and inputs the detection result to the controller 70. The water temperature sensor 54 may detect, for example, the temperature of the water piping 46. The water temperature sensor 54 may detect the temperature of the water piping 46 that sends the cooling water from the fuel cell device 32 to the heat exchanger 33, or may detect the temperature of the water piping 46 that sends the cooling water from the heat exchanger 33 to the fuel cell device 32.

[0070] The controller 70 includes a computer having an arithmetic processing unit and a memory. The controller 70 performs various controls by the arithmetic processing unit executing a program prestored in the memory. Specifically, the following controls are performed.

[0071] When the work machine 100 performs various actual tasks such as excavation and ground leveling at a work site, the controller 70 performs control such as the following, for example. That is, during actual tasks, the controller 70 controls the power generated in the fuel cell device 32 so that a target power corresponding to the work load at that time is supplied to the electric motor 34A. At this time, the controller 70 performs control so that hydrogen corresponding to the target power is supplied from the hydrogen tank 31 to the fuel cell device 32. Also, during actual tasks, the controller 70 draws air outside the machine room 14 into the machine room 14 as cooling air CA, adjusts the rotation speed of the cooling fan 35 so that sufficient ventilation is performed to exhaust the drawn-in cooling air CA to the outside of the machine room 14, and generates an appropriate amount of cooling air CA according to the situation at that time.

[0072] During actual operation, the controller 70 controls the water pump to circulate the cooling water so that the temperature of the fuel cell device 32 is maintained within an allowable range. Thermal energy generated when the fuel cell device 32 generates power is transferred to the cooling water. That is, heat exchange occurs between the fuel cell device 32 and the cooling water. The cooling water that has exchanged heat with the fuel cell device 32 is sent to the heat exchanger 33 through the water piping 46, where it exchanges heat with the cooling air CA. This causes the temperature of the cooling water to drop, and the temperature of the cooling air CA to rise. The high-temperature cooling air CA that has passed through the heat exchanger 33 is discharged from the exhaust port 17 to the outside of the machine room 14. The cooling water whose temperature has been lowered in the heat exchanger 33 returns to the fuel cell device 32 through the water piping 46, and exchanges heat with the fuel cell device 32 again.

[0073] The controller 70 may perform control to adjust the rotation speed of the cooling fan 35 in accordance with the temperature detected by the water temperature sensor 54. Specifically, for example, the controller 70 may perform control to increase the rotation speed of the cooling fan 35 when the temperature detected by the water temperature sensor 54 becomes equal to or higher than a preset water temperature specified value. This allows the temperature of the cooling water to be sufficiently lowered in the heat exchanger 33, and as a result, the fuel cell device 32 can be appropriately cooled.

[0074] Next, the control by the controller 70 during hydrogen filling will be described. The work machine 100 is equipped with a hydrogen filling socket 45 and a filling device connection switch 55. The hydrogen filling socket 45 is connected to the hydrogen tank 31 via piping 44. The hydrogen filling socket 45 has a hydrogen filling port. FIG. 8 is a cross-sectional view showing the inside of the machine room 14, showing the state in which a terminal 49 of a hydrogen filling device 48 is connected to the hydrogen filling port of the hydrogen filling socket 45. When the terminal 49 of the hydrogen filling device 48 is connected to the hydrogen filling port of the hydrogen filling socket 45, a signal indicating the connection (connection signal) is input from the filling device connection switch 55 to the controller 70.

[0075] When the terminal 49 of the hydrogen filling device 48 is connected to the hydrogen filling port of the hydrogen filling socket 45, hydrogen filling from the hydrogen filling device 48 to the hydrogen tank 31 begins, and the controller 70 monitors the temperature of the hydrogen gas or a temperature related thereto during hydrogen filling. The controller 70 prohibits actual work during hydrogen filling.

[0076] During hydrogen filling, hydrogen gas is filled into the hydrogen tank 31 under high pressure by the hydrogen filling device 48, so that the temperature of the hydrogen gas in the hydrogen tank 31 rises. The controller 70 may start the rotation of the cooling fan 35 at the start of hydrogen filling, and may control the cooling fan 35 to increase its rotation speed when the temperature detected by the hydrogen tank ambient temperature sensor 51 becomes equal to or higher than a first specified value set in advance during hydrogen filling. The controller 70 may also control the cooling fan 35 not to start rotating but to maintain a stopped state at the start of hydrogen filling, and may control the cooling fan 35 to start rotating when the temperature detected by the hydrogen tank ambient temperature sensor 51 becomes equal to or higher than a second specified value set in advance during hydrogen filling, and may further control the cooling fan 35 to increase its rotation speed when the temperature detected by the hydrogen tank ambient temperature sensor 51 becomes equal to or higher than a third specified value that is higher than the second specified value. Since the rotation speed of the cooling fan 35 is automatically increased by the control of the controller 70 in this way, even if the temperature of the hydrogen gas in the hydrogen tank 31 rises, the temperature rise around the hydrogen tank 31 is effectively suppressed.

[0077] The controller 70 may also control the cooling fan 35 to start rotating when hydrogen filling starts, and to increase the number of revolutions of the cooling fan 35 when the temperature detected by the hydrogen gas temperature sensor 52 becomes equal to or higher than a fourth specified value set in advance during hydrogen filling. The controller 70 may also control the cooling fan 35 to start rotating and maintain a stopped state when hydrogen filling starts, and to start rotating the cooling fan 35 when the temperature detected by the hydrogen gas temperature sensor 52 becomes equal to or higher than a fifth specified value set in advance during hydrogen filling, and may also control the cooling fan 35 to increase the number of revolutions when the temperature detected by the hydrogen gas temperature sensor 52 becomes equal to or higher than a sixth specified value that is higher than the fifth specified value. Since the number of revolutions of the cooling fan 35 is automatically increased by the control of the controller 70 in this way, even if the temperature of the hydrogen gas in the hydrogen tank 31 rises, the temperature rise around the hydrogen tank 31 is effectively suppressed.

[0078] Next, the control by the controller 70 in the event of hydrogen leakage will be described. When the hydrogen gas sensor 53 detects hydrogen gas while the cooling fan 35 is stopped, the controller 70 may control the cooling fan 35 to start rotating. Also, when the hydrogen gas sensor 53 detects hydrogen gas while the cooling fan 35 is rotating, the controller 70 may control the cooling fan 35 to increase its rotation speed. In the case where a plurality of hydrogen gas sensors 53 are disposed in the machine room 14, the controller 70 may determine that the hydrogen gas sensor 53 has detected hydrogen gas when one or more of the hydrogen gas sensors 53 detect hydrogen gas, and perform the above-mentioned control. In this way, the rotation speed of the cooling fan 35 is automatically increased by the control of the controller 70, and ventilation of the machine room 14 is promoted. This further improves safety in the event of hydrogen leakage. In this control, it is preferable that the controller 70 controls the cooling fan 35 to increase its rotation speed to a maximum value when the hydrogen gas sensor 53 detects hydrogen gas. This control in the event of a hydrogen leak is preferably performed both during actual operation and during hydrogen filling, and more preferably is performed constantly while the controller 70 is running. Furthermore, when starting the rotation of the cooling fan 35 or increasing the rotation speed of the cooling fan 35 in the event of a hydrogen leak, the rotation direction of the impeller 35A of the cooling fan 35 may be controlled to be opposite to that in normal operation. Note that in this embodiment, the control to start the rotation of the cooling fan 35 from a state in which the cooling fan 35 is stopped is included in the control for increasing the rotation speed of the cooling fan 35.

[0079] [Second embodiment] Next, a work machine 100 according to a second embodiment of the present disclosure will be described. The work machine 100 according to the second embodiment is the same as the work machine 100 according to the first embodiment in that it has a basic structure as shown in Figures 1 to 4.

[0080] Fig. 9 is a side view showing the arrangement of electronic devices 34 and hydrogen-related equipment 36 arranged on the revolving frame 20 of a work machine 100 according to the second embodiment. In Fig. 9, the wall portion 13 and cooling fan 35 are omitted, and the positions of the cab 11 and heat exchanger 33 are indicated by two-dot chain lines. Fig. 10 is a diagram showing the inside of the machine room 14 of the work machine 100 according to the second embodiment, and is a cross-sectional view taken along line AA in Fig. 1. Fig. 10 shows various devices arranged in the machine room 14, and also indicates with arrows the flow of cooling air CA in the machine room 14.

[0081] As shown in Fig. 10, the work machine 100 according to the second embodiment comprises a hydrogen tank 31 that stores hydrogen, a fuel cell device 32 to which hydrogen (hydrogen gas) is supplied from the hydrogen tank 31, a heat exchanger 33 that exchanges heat with cooling air CA, electronic equipment 34 for operating the work machine 100, and a wall section 13 that defines a machine room 14. The hydrogen tank 31 is disposed above the electronic equipment 34 in the machine room 14, and is disposed upstream of the heat exchanger 33 in the flow direction of the cooling air CA. These configurations are the same as those of the work machine 100 according to the first embodiment, and produce the same effects as those of the first embodiment.

[0082] In the second embodiment as well, the wall portion 13 has a shape (e.g., a box shape) capable of defining the machine room 14, and has an intake port 16 and an exhaust port 17. In the second embodiment as well, the portion in the wall portion 13 where the intake port 16 and the exhaust port 17 are formed are not limited to the specific example shown in Fig. 10, and can be formed in various portions as in the first embodiment.

[0083] In the second embodiment as well, the work machine 100 is provided with a cooling fan 35 that forms a flow of cooling air CA. The cooling fan 35 can effectively form a flow of cooling air CA from the intake port 16 to the exhaust port 17 in the machine room 14. The cooling fan 35 includes an impeller, a fan motor (not shown), and a shroud (not shown).

[0084] In the work machine 100 shown in Figures 9 and 10, the hydrogen-related equipment 36 including the hydrogen tank 31 and the fuel cell device 32 is disposed above the electronic equipment 34. In this case, even if hydrogen gas leaks from at least one of the hydrogen tank 31 and the fuel cell device 32 included in the hydrogen-related equipment 36, the hydrogen gas moves upward from the hydrogen-related equipment 36 in the machine room 14, and is therefore prevented from reaching the electronic equipment 34 disposed below the hydrogen-related equipment 36. This improves safety in the event of a hydrogen leak. Note that in the machine room 14, the hydrogen-related equipment 36 may be supported by a support frame (not shown, for example, similar to the support frame 60 in the first embodiment) so as to be disposed above the electronic equipment 34.

[0085] 10, the hydrogen-related equipment 36 further includes a hydrogen filling socket 45 having a hydrogen filling port, hydrogen piping 40 connecting the hydrogen tank 31 and the fuel cell device 32, and piping 44 connecting the hydrogen tank 31 and the hydrogen filling socket 45. In this case, even if hydrogen gas leaks from at least one of the hydrogen filling port of the hydrogen filling socket 45 included in the hydrogen-related equipment 36, the hydrogen piping 40, and the piping 44, the hydrogen gas moves upward from the hydrogen-related equipment 36 in the machine room 14, and is therefore prevented from reaching the electronic equipment 34 arranged below the hydrogen-related equipment 36. This further improves safety in the event of a hydrogen leak.

[0086] The hydrogen-related equipment 36 is disposed at a position above the rear portion 22B of the rising block 22 and at a position overlapping the rear portion 22B when viewed from the top-bottom direction. Specifically, the hydrogen-related equipment 36 is disposed so as to overlap the rear portions 22B of the left and right rising plates 23, 23 of the rising block 22 when viewed from the top-bottom direction. In this case, the hydrogen-related equipment 36 can be disposed efficiently by utilizing the space above the rising block 22 inside the machine room 14, which has a limited size. As shown in FIG. 9, the hydrogen-related equipment 36 is disposed so as to be located directly above the rear portion 22B of the rising block 22 of the revolving frame 20. By disposing the hydrogen-related equipment 36, which is large and heavy, directly above the rear portion 22B of the rising block 22, it is possible to position the center of gravity of the entire working machine 100 as far back and as low as possible.

[0087] 10, the electronic devices 34 are disposed to the right and left of the rear portion 22B of the rising block 22 of the revolving frame 20. That is, the electronic devices 34 include a right electronic device 341 disposed adjacent to the right side of the rear portion 22B of the rising block 22, and a left electronic device 343 disposed adjacent to the left side of the rear portion 22B of the rising block 22. By disposing the right electronic device 341 and the left electronic device 343 among the electronic devices 34 in the spaces formed to the right and left of the rear portion 22B of the rising block 22, safety in the event of a hydrogen leak can be improved, and the efficiency of mounting parts constituting the work machine inside the machine room 14, which has a limited size, can be improved.

[0088] Moreover, the electronic devices 34 are disposed between the left and right standing plates 23, 23 of the revolving frame 20. That is, the electronic devices 34 include a central electronic device 342 disposed between the left and right standing plates 23, 23. By disposing the central electronic device 342 of the electronic devices 34 in the space formed between the left and right standing plates 23, 23, safety in the event of a hydrogen leak can be improved, and the efficiency of mounting the parts that constitute the work machine 100 inside the machine room 14, which has a limited size, can be improved.

[0089] In the second embodiment, the electronic device 34 may include the electric motor, the inverter, the converter, the battery, the compressor, the water pump, and the heater described in the first embodiment. Each of these devices is disposed in the space on the right side of the rear part 22B of the standing body 22 in FIG. 10, the space on the left side of the rear part 22B, or the space between the left and right standing plates 23, 23.

[0090] In the second embodiment, the controller 70 may also perform the same control as in the first embodiment. For example, during actual work, the controller 70 adjusts the rotation speed of the cooling fan 35 so that the machine room 14 is sufficiently ventilated, and generates a cooling air CA with an appropriate volume according to the situation at that time. Also, during actual work, the controller 70 controls the water pump to circulate the cooling water so that the temperature of the fuel cell device 32 is maintained within an allowable range. Thermal energy generated when the fuel cell device 32 generates electricity is transferred to the cooling water.

[0091] The controller 70 may also perform control to adjust the rotation speed of the cooling fan 35 in accordance with the temperature detected by a water temperature sensor (not shown). Specifically, for example, the controller 70 may perform control to increase the rotation speed of the cooling fan 35 when the temperature detected by the water temperature sensor becomes equal to or higher than a preset water temperature specified value. This allows the temperature of the cooling water to be sufficiently lowered in the heat exchanger 33, and as a result, the fuel cell device 32 can be appropriately cooled.

[0092] In addition, the controller 70 may perform control to increase the rotation speed of the cooling fan 35 when the temperature detected by a hydrogen tank ambient temperature sensor (not shown) during hydrogen filling becomes equal to or higher than a first predetermined value.

[0093] In addition, the controller 70 may perform control to increase the rotation speed of the cooling fan 35 when the temperature detected by a hydrogen gas temperature sensor (not shown) during hydrogen filling becomes equal to or higher than a second predetermined value.

[0094] Furthermore, when the hydrogen gas sensor 53 detects hydrogen gas, the controller 70 may perform control to increase the rotation speed of the cooling fan 35. In this manner, the rotation speed of the cooling fan 35 is automatically increased under the control of the controller 70, and ventilation of the machine room 14 is promoted.

[0095] FIG. 11 is a side view showing the arrangement of electronic devices and hydrogen-related equipment arranged on the rotating frame 20 of a work machine 100 relating to variant example 1 of the second embodiment, FIG. 12 is a view showing the inside of the machine room 14 of the work machine 100 and is a cross-sectional view taken along line AA in FIG. 1, and FIG. 13 is a view showing the inside of the machine room 14 of the work machine 100 and is a cross-sectional view taken along line BB in FIG. 1.

[0096] The work machine 100 according to the first modification shown in FIG. 11 is different from the work machine 100 shown in FIGS. 9 and 10 in that it further includes a first partition wall 91 disposed between the hydrogen-related equipment 36 and the electronic equipment 34 in the machine room 14. The first partition wall 91 is a member capable of separating a space (lower electronic equipment space) in which the right electronic equipment 341, the center electronic equipment 342, and the left electronic equipment 343 are disposed, from a space (upper hydrogen-related equipment space) in which the hydrogen-related equipment 36 located above these electronic equipment 341, 342, 343 is disposed. The first partition wall 91 may be formed of, for example, a plate-shaped member. In this first modification, even if hydrogen gas leaks from the hydrogen-related equipment 36, the first partition wall 91 more reliably prevents the leaked hydrogen gas from reaching the electronic equipment 341, 342, 343, and the lower electronic equipment space and the upper hydrogen-related equipment space are separated by the first partition wall 91, so that safety in the event of hydrogen leakage can be further improved.

[0097] Furthermore, in the work machine 100 according to the first modification, it is preferable that the hydrogen-related equipment 36 is modularized on the first bulkhead 91. For example, it is preferable that the parts that make up the hydrogen-related equipment 36 are unitized and configured so as to be lifted as a unit by a crane or the like. This can improve the ease of operation when arranging the hydrogen tank 31 and fuel cell device 32 included in the hydrogen-related equipment 36 on the first bulkhead 91.

[0098] The work machine 100 according to the first modification is equipped with a first electronic device and a second electronic device. The first electronic device includes the above-mentioned right electronic device 341, center electronic device 342, and left electronic device 343. As shown in Fig. 12, in the work machine 100 according to the first modification, the second electronic device 344 is an electronic device separate from the first electronic device, and is disposed in a position aligned horizontally (in the first modification, in the left-right direction) with the hydrogen-related equipment 36.

[0099] As shown in Figures 12 and 13, the work machine 100 according to this modified example 1 further includes a second partition wall 92 disposed between the hydrogen-related equipment 36 and the second electronic device 344 in the machine room 14. Even if it is necessary to dispose the second electronic device 344 in addition to the first electronic device in the machine room 14 and to dispose it in a position horizontally aligned with the hydrogen-related equipment 36, the area in which the hydrogen-related equipment 36 is disposed and the area in which the second electronic device 344 is disposed are separated by the second partition wall 92. Therefore, even if hydrogen gas leaks from the hydrogen-related equipment 36, the second partition wall 92 more reliably prevents the leaked hydrogen gas from reaching the second electronic device 344, and safety in the event of a hydrogen leak can be ensured.

[0100] 12, the upper cover 13U of the wall portion 13 further has one or more ventilation holes 19 communicating with the space in which the hydrogen-related equipment 36 is arranged (upper hydrogen-related equipment space). This promotes ventilation in the upper hydrogen-related equipment space. It is preferable that the ventilation hole 19 is shaped so that the upper part is covered with a plate member to prevent rainwater and dust from entering the interior of the machine room 14 and that the side is open for ventilation.

[0101] FIG. 14 is a diagram showing the inside of the machine room 14 of the work machine 100 according to variant example 2 of the second embodiment, and is a cross-sectional view taken along line AA in FIG. 1, and FIG. 15 is a diagram showing the inside of the machine room 14 of the work machine 100, and is a cross-sectional view taken along line BB in FIG. 1.

[0102] The work machine 100 according to the modified example 2 shown in Figures 14 and 15 differs from the modified example 1 shown in Figures 12 and 13 in that it further includes a third electronic device 345, a third partition 93, and a fourth partition 94.

[0103] The third electronic device 345 is an electronic device separate from the first electronic device and the second electronic device 344, and is arranged in a position so as to be aligned horizontally (in this variant 1, in the front-to-back direction) with the hydrogen-related device 36. The third partition 93 is arranged between the hydrogen-related device 36 and the third electronic device 345 in the machine room 14. The fourth partition 94 is arranged between the hydrogen-related device 36 and the heat exchanger 33 in the machine room 14. It should be noted that in this variant 2, the fourth partition 94 may be omitted.

[0104] In variant example 2 shown in Figures 12 and 13, even if it is necessary to further arrange a third electronic device 345 in addition to the first electronic device and second electronic device 344 in the machine room 14, and even if it is necessary to arrange it in a position horizontally aligned with the hydrogen-related equipment 36, the area in which the hydrogen-related equipment 36 is arranged and the area in which the third electronic device 345 is arranged are separated by the third partition 93, so that even if hydrogen gas leaks from the hydrogen-related equipment 36, the third partition 93 more reliably prevents the leaked hydrogen gas from reaching the third electronic device 345, thereby ensuring safety in the event of a hydrogen leak.

[0105] 14, in this second modification, the upper cover 13U of the wall portion 13 has one or more ventilation holes 19 communicating with the space in which the hydrogen-related equipment 36 is disposed (upper hydrogen-related equipment space), thereby promoting ventilation in the upper hydrogen-related equipment space.

[0106] [Third embodiment] Next, a work machine 100 according to a third embodiment of the present disclosure will be described. The work machine 100 according to the third embodiment is the same as the work machine 100 according to the first embodiment in that it has a basic structure as shown in Figures 1 to 4.

[0107] Figure 16 is a diagram showing the inside of the machine room 14 of the work machine 100 according to the third embodiment, and is a cross-sectional view taken along line AA in Figure 1. Figure 17 is a diagram showing the inside of the machine room 14 of the work machine 100 according to a modified example of the third embodiment, and is a cross-sectional view taken along line BB in Figure 1.

[0108] Each of the work machine 100 shown in Fig. 16 and the work machine 100 shown in Fig. 17 comprises a hydrogen tank 31 that stores hydrogen, a fuel cell device 32 to which hydrogen is supplied from the hydrogen tank 31, a heat exchanger 33 that exchanges heat with cooling air CA, electronic equipment 34 for operating the work machine 100, a wall section 13 that defines the machinery room 14, and a partition wall 90 that is arranged between the hydrogen tank 31 and the electronic equipment 34 in the machinery room 14. The hydrogen tank 31 is arranged upstream of the heat exchanger 33 in the flow direction of the cooling air CA in the machinery room 14.

[0109] In each of these working machines 100, a partition wall 90 separates an area in the machine room 14 in which the hydrogen tank 31 is disposed from an area in which the electronic device 34 is disposed. Therefore, even if hydrogen gas leaks from the hydrogen tank 31 or its vicinity (for example, a hydrogen filling port, etc.), the leaked hydrogen gas is prevented from reaching the electronic device 34 in the machine room 14. This improves safety in the event of a hydrogen leak. In addition, the hydrogen tank 31, which is disposed upstream of the heat exchanger 33 in the machine room 14, is supplied with cooling air CA before passing through the heat exchanger 33, i.e., cooling air CA before its temperature increases due to heat exchange in the heat exchanger 33, so that a temperature rise around the hydrogen tank 31 is suppressed. Suppressing a temperature rise around the hydrogen tank 31 contributes to suppressing an increase in the filling time required to fill the hydrogen tank 31 with hydrogen. In addition, if the hydrogen tank 31 is, for example, a resin tank, suppressing a temperature rise around the hydrogen tank 31 also contributes to suppressing deterioration of the resin tank.

[0110] In the work machine 100 shown in Fig. 16, the machinery room 14 is formed between the cab 11 and the counterweight 12. The hydrogen tank 31 is disposed upstream of the fuel cell device 32 and the electronic devices 34 in the flow direction of the cooling air CA, and the fuel cell device 32 and the electronic devices 34 are disposed upstream of the heat exchanger 33 in the flow direction of the cooling air CA. The partition wall 90 has a shape that separates the area in the machinery room 14 where the hydrogen tank 31 is disposed from the area where the fuel cell device 32 and the electronic devices 34 are disposed. The partition wall 90 may have a communication port 90A that communicates between the area where the hydrogen tank 31 is disposed and the area where the fuel cell device 32 and the electronic devices 34 are disposed. In the work machine 100 shown in Figure 16, the hydrogen tank 31 is not positioned above the electronic equipment 34 in the machine room 14, but is positioned so as to be aligned horizontally (left-right) with the electronic equipment 34. However, since the partition wall 90 as described above is positioned between the area in which the hydrogen tank 31 is located and the area in which the fuel cell device 32 and the electronic equipment 34 are located, safety is improved in the event of a hydrogen leak.

[0111] In the working machine 100 shown in FIG. 17, the machine room 14 is formed between the cab 11 and the weight cover 13W (rearmost cover 13W). That is, the machine room 14 includes a part of the space (weight space) covered by the weight cover 13W. The space (electronic device space) in which the fuel cell device 32 and the electronic device 34 are arranged and the weight space are arranged in a line in the front-rear direction via a partition wall 90. In this modified example 2, a path in which the cooling air CA flows through the intake port 16, the weight space, and the heat exchanger 33 in this order is formed parallel to a path in which the cooling air CA flows through the intake port 16, the electronic device space, and the heat exchanger 33 in this order. The hydrogen tank 31 is arranged upstream of the heat exchanger 33 in the flow direction of the cooling air CA. Similarly, the fuel cell device 32 and the electronic device 34 are arranged upstream of the heat exchanger 33 in the flow direction of the cooling air CA. The partition wall 90 has a shape that separates the area in the machine room 14 where the hydrogen tank 31 is arranged from the area where the fuel cell device 32 and the electronic devices 34 are arranged. The partition wall 90 may have a communication port 90A that communicates between the area where the hydrogen tank 31 is arranged and the area where the fuel cell device 32 and the electronic devices 34 are arranged. In the work machine 100 shown in FIG. 17, the hydrogen tank 31 is not arranged above the electronic devices 34 in the machine room 14, but is arranged in a position aligned horizontally (in the front-to-rear direction) with the electronic devices 34. However, since the partition wall 90 as described above is arranged between the area where the hydrogen tank 31 is arranged and the area where the fuel cell device 32 and the electronic devices 34 are arranged, safety in the event of a hydrogen leak is improved.

[0112] [Variations] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and includes, for example, the following modified examples.

[0113] (A) About Partitions Each of the work machines according to the second and third embodiments may be provided with the partition 18 in the first embodiment.

[0114] (B) Electronic Devices In the second embodiment, electronic devices 341 and 343 are arranged on both the right and left of the rear portion 22B of the standing body 22, and electronic device 342 is arranged between the left and right standing boards 23, 23, but one or two of these electronic devices 341, 342, 343 may be omitted. In addition, in the work machine according to the present disclosure, the electronic device arranged in the machine room may be at least one of the electric motor, inverter, converter, battery, compressor, water pump, and heater. In other words, some of the electric motor, inverter, converter, battery, compressor, water pump, and heater may be arranged outside the machine room.

[0115] (C) Hydraulic Equipment In the first to third embodiments, the hydraulic pump 81 is disposed inside the machine room 14, but the hydraulic pump 81 may be disposed outside the machine room 14. Moreover, a part of the hydraulic pump 81 may be disposed inside the machine room 14, and another part of the hydraulic pump 81 may be disposed outside the machine room 14.

[0116] For example, in a work machine 100 shown in FIG. 18, a hydraulic pump 81 is disposed in the front (e.g., right front) of the revolving frame 20 of the upper revolving body 2. In this work machine 100, a hydraulic equipment area in which hydraulic equipment 37 is disposed is formed in the right front part of the revolving frame 20. The hydraulic equipment 37 includes a hydraulic pump 81 that discharges hydraulic oil, and a hydraulic oil tank 82 that stores hydraulic oil to be supplied to the hydraulic pump 81. The hydraulic oil tank 82 is disposed at the front end of the hydraulic equipment area, and the hydraulic pump 81 is disposed rearward of the hydraulic oil tank 82. In the modified example shown in FIG. 18, the hydraulic pump 81 is disposed rearward (directly behind) the hydraulic oil tank 82, and no other equipment is interposed between the hydraulic oil tank 82 and the hydraulic pump 81, so that the length of the piping connecting the hydraulic oil tank 82 and the hydraulic pump 81 can be reduced. In the specific example shown in Fig. 19, the hydraulic pump 81 is accommodated in an equipment accommodating space inside the equipment accommodating chamber 15 defined by an equipment cover 13H (specifically, a second equipment cover 13H2 described later) shown in Fig. 19, and the hydraulic oil tank 82 is disposed in front of the equipment cover 13H. However, the entire hydraulic equipment 37 may be accommodated in the equipment accommodating space inside the equipment accommodating chamber 15 defined by the equipment cover 13H.

[0117] Further, the electronic device area, which is an area in which the electronic device 34 is arranged, is formed behind the hydraulic device area. The electronic device 34 includes an electric motor 34A, an inverter 34B, a converter 34C, and a battery 34D. The electric motor 34A is arranged at the front end of the electronic device area. That is, the hydraulic oil tank 82, the hydraulic pump 81, and the electric motor 34A are arranged from front to rear in this order. In the electronic device area, the inverter 34B, the converter 34C, and the battery 34D are arranged behind the electric motor 34A. In this modification, the electronic device area is formed behind the hydraulic device area, and the electric motor 34A is arranged at the front end of the electronic device area, so that the wiring for supplying power to the electric motor 34A can be accommodated within the electronic device area, and the wiring can be prevented from becoming long. In this modification, the electric motor 34A, the inverter 34B, the converter 34C, and the battery 34D are arranged from front to rear in this order, but the arrangement order of these devices is not limited to the specific example shown in FIG. 18.

[0118] Furthermore, the fuel cell device 32 is disposed immediately to the left of the rear end of the electronic device area (battery 34D in the specific example shown in FIG. 18). The hydrogen tank 31 is disposed on top of the fuel cell device 32. The hydrogen tank 31 is disposed above the rear end of the electronic device area. By disposing a part or all of the hydraulic equipment 37 outside the machinery room 14, it is possible to mount the hydrogen tank 31, fuel cell device 32 and heat exchanger 33 inside the machinery room 14, which is a limited space, and to mount a part or all of the electronic equipment 34 inside the machinery room 14. Note that in the modified examples shown in FIGS. 18 and 19 as well, the hydrogen tank 31 is disposed upstream of the heat exchanger 33 in the machinery room 14 in the flow direction of the cooling air.

[0119] (D) Ventilation holes In the second embodiment, one or more ventilation holes 19 are formed in the upper cover 13U of the wall portion 13, but the same ventilation holes 19 as those in the second embodiment may be formed in at least one of the first embodiment and the third embodiment. For example, in the work machine 100 shown in Figs. 18 and 19, a pair of left and right ventilation holes 19 are formed in the upper cover 13U of the wall portion 13. The left ventilation hole 19 is formed so as to discharge the air inside the machine room 14 to the left to the outside of the machine room 14, and the right ventilation hole 19 is formed so as to discharge the air inside the machine room 14 to the right to the outside of the machine room 14. Specifically, each of the pair of ventilation holes 19 is formed by a gap between the upper cover 13U and a plate member 19A that covers an opening (not shown) formed in the upper cover 13U from above. In the work machine 100 shown in FIG. 19, the left ventilation opening 19 is, for example, a gap between the left edge of the left plate member 19A and the upper cover 13U, and the right ventilation opening 19 is, for example, a gap between the right edge of the right plate member 19A and the upper cover 13U. In this manner, it is preferable that the directions of the air discharged from the pair of ventilation openings 19 are opposite to each other. Also, the direction of the air discharged from the ventilation openings 19 may be backward. It is preferable that the direction of the air discharged from the ventilation openings 19 is such that the air discharged from the ventilation openings 19 tends to move away from the work machine 100. In the specific example shown in FIG. 19, the distance between the right ventilation opening 19 and the right edge of the upper cover 13U is smaller than the distance between the left ventilation opening 19 and the left edge of the upper cover 13U, so that the air discharged from the right ventilation opening 19 tends to move away from the work machine 100 compared to the air discharged from the left ventilation opening 19.

[0120] (E) About the filling port In the first embodiment, the hydrogen filling socket 45 is arranged inside the machine room 14 as shown in FIG. 8, and the terminal 49 of the hydrogen filling device 48 is connected to the hydrogen filling port of the hydrogen filling socket 45 from outside the machine room 14 through the intake port 16, but the present invention is not limited to such a configuration. For example, in the working machine 100 shown in FIG. 18 and FIG. 19, a structure for accessing the hydrogen filling port may be formed in a portion other than the intake port 16. Specifically, as shown in FIG. 19, a hydrogen filling opening 25 may be formed in a portion of the front cover 13F of the wall portion 13 that defines the machine room 14. This hydrogen filling opening 25 is an opening for accessing the hydrogen filling port located inside the machine room 14 from outside the machine room 14, and is an opening that communicates with the inside of the machine room 14. It is preferable that an openable or removable cover is attached to this hydrogen filling opening 25 to prevent rainwater and dust from entering the inside of the machine room 14. By providing such a cover, the operator can switch between the open state and the closed state of the hydrogen filling opening 25 by operating the cover. For example, the hydrogen filling opening 25 is open when hydrogen filling is performed, and is closed when hydrogen filling is not performed. It is preferable to place a static electricity removal sheet near the hydrogen filling opening 25 to remove static electricity charged on the body of an operator by touching it with his or her hand. The hydrogen filling opening 25 is not limited to being formed on a cover that covers the front side of the machine room 14, but may be formed on a cover that covers the right or left side of the machine room, may be formed on a cover that covers the rear side of the machine room 14, or may be formed on a cover that covers the upper side of the machine room 14.

[0121] (F) Inspection hatches An inspection hatch for inspecting the hydrogen tank 31 housed inside the machine room 14 may be formed in the wall 13 of the work machine 100 shown in Figures 18 and 19. Specifically, for example, in the work machine 100 shown in Figure 19, an inspection hatch 26 for inspecting the hydrogen tank 31 inside the machine room 14 from outside the machine room 14 is formed in a portion of the front cover 13F of the wall 13 that defines the machine room 14. This inspection hatch 26 is an opening that opens the internal space of the machine room 14 to the outside of the machine room 14 to visually check the hydrogen tank 31. It is preferable that an openable or removable cover is attached to this inspection hatch 26 to prevent rainwater and dust from entering the inside of the machine room 14. Not only one inspection hatch 26 but also multiple inspection hatches 26 may be formed in the wall 13. In addition, the inspection hatch 26 is not limited to being a cover that covers the front side of the machine room 14, but may be formed in a cover that covers the right or left side of the machine room 14, may be formed in a cover that covers the rear side of the machine room 14, or may be formed in a cover that covers the upper side of the machine room 14.

[0122] (G) Equipment Covers As shown in FIG. 19, the equipment cover 13H defining the equipment storage chamber 15 may have a stepped portion 131 with a low height in part. Specifically, it is as follows. As shown in FIG. 19, the upright plate 23 of the upright body 22 of the swivel frame 20 is formed with an insertion hole 23A through which a connecting pin for rotatably connecting the base end of the boom cylinder 7 is inserted, and an insertion hole 23B through which a connecting pin for rotatably connecting the base end 4A of the boom 4 is inserted. The equipment cover 13H defining the equipment storage chamber 15 includes a first equipment cover 13H1 and a second equipment cover 13H2 located in front of the first equipment cover 13H1. The upper surface of the second equipment cover 13H2 is located below the upper surface of the first equipment cover 13H1 and below the horizontal line L1. The horizontal line L1 is a straight line (imaginary line) that passes through the center of the insertion hole 23B and is parallel to the left-right direction. The step portion 131 is formed by positioning the upper surface of the second equipment cover 13H2 lower than the upper surface of the first equipment cover 13H1. By forming such a step portion 131, the equipment cover 13H does not interfere with the connecting pin when the connecting pin is attached to and detached from the insertion hole 23B, improving the workability of the attachment and detachment work. A hydraulic oil tank 82 is disposed in front of the step portion 131. In the specific example shown in FIG. 19, the upper surface of the second equipment cover 13H2 is positioned lower than the upper surface of the hydraulic oil tank 82. In this case, the upper surface of the second equipment cover 13H2 is positioned lower than the upper surface of the first equipment cover 13H1 and the upper surface of the hydraulic oil tank 82, so that the step portion 131 forms a recessed portion recessed downward. For example, a hydraulic pump 81 may be disposed in the internal space defined by the second equipment cover 13H2.

[0123] (H) Actuators In the first to third embodiments, all of the multiple actuators are hydraulic actuators that operate by receiving a supply of hydraulic oil discharged from the hydraulic pump 81, but at least some of the multiple actuators may be configured as actuators other than hydraulic actuators. Specifically, for example, at least some of the multiple actuators may be electric actuators. The electric actuators may be configured to perform operations such as expansion and contraction, rotation, etc., by an electric motor that operates by receiving a supply of electric power from at least one of the fuel cell device 32 and a battery. [Explanation of symbols]

[0124] 4: Boom 4A: Base end of boom 13: Wall part 14: Machine room 16: Air intake 17: Exhaust port 18: Partition 20: Swivel frame 21: Frame body 22: Erected body 22A: Boom mounting part 22B: Rear part 23: Standing board 31: Hydrogen tank 32:Fuel cell device 33: Heat exchanger 34:Electronic equipment 35: Cooling fan 36: Hydrogen-related equipment 48: Hydrogen filling equipment 51: Hydrogen tank ambient temperature sensor (an example of a temperature detector) 52: Hydrogen gas temperature sensor (an example of a temperature detector) 53: Hydrogen gas sensor 70: Controller 81: Hydraulic pump 90~94: Partition wall 100: Working machines CA: Cooling air

Claims

1. A hydrogen tank for storing hydrogen; A heat exchanger that exchanges heat with cooling air; Electronic equipment for operating the work machine; A machine room, A working machine, wherein the hydrogen tank is disposed in the machine room, above the electronic equipment, and upstream of the heat exchanger in a flow direction of the cooling air.

2. the machine room is defined by a wall portion having an air intake port for drawing air outside the machine room into the machine room as the cooling air, and an exhaust port for discharging the cooling air inside the machine room to the outside of the machine room, The work machine according to claim 1 , further comprising a cooling fan that forms the flow of cooling air.

3. 3. The work machine according to claim 2, wherein at least a portion of the intake port is formed at a height position horizontally aligned with the hydrogen tank or at a position higher than the hydrogen tank.

4. 3. The work machine according to claim 2, wherein at least a portion of the exhaust port is formed at a height position horizontally aligned with the hydrogen tank or at a position higher than the hydrogen tank.

5. a temperature detector for detecting the temperature of the hydrogen tank or a temperature related thereto; and a controller, 3. The work machine according to claim 2, wherein the controller performs control to increase the rotation speed of the cooling fan when the temperature detected by the temperature detector reaches or exceeds a preset specified value.

6. a hydrogen detector for detecting hydrogen in the machine room; A controller, 3. The work machine according to claim 2, wherein the controller performs control to increase the rotation speed of the cooling fan when the hydrogen detector detects hydrogen.

7. The work machine according to any one of claims 1 to 6, further comprising a partition for preventing the cooling air that has passed through the heat exchanger from mixing with the cooling air before passing through the heat exchanger in the machine room.

8. further comprising a fuel cell device to which hydrogen is supplied from the hydrogen tank; 7. The work machine according to claim 1, wherein the fuel cell device is disposed at a position lower than the hydrogen tank and overlaps with the hydrogen tank when viewed from above and below.

9. further comprising a fuel cell device to which hydrogen is supplied from the hydrogen tank; 7. The work machine according to claim 1, wherein hydrogen-related equipment including the hydrogen tank and the fuel cell device is disposed above the electronic equipment.

10. Boom and a pivoting frame, The swivel frame has a frame body and an upright body that stands up from the frame body and extends forward and backward, the riser body includes a boom mounting portion to which a base end portion of the boom is attached, and a rear portion that is located rearward of the boom mounting portion and has a lower height than the boom mounting portion, The work machine according to claim 9 , wherein the hydrogen-related equipment is disposed at a position higher than the rear portion of the upright body and at a position overlapping with the rear portion when viewed from above and below.

11. The work machine according to claim 10 , wherein the electronic device is disposed on at least one of the right and left sides of the rear portion of the standing body.

12. The upright body includes left and right upright plates extending forward and backward from the frame body, The left and right upright plates are arranged at intervals from each other in the left-right direction, The work machine according to claim 10 , wherein the electronic device is disposed between the left and right upright plates.

13. The work machine according to claim 9 , further comprising a partition wall disposed between the hydrogen-related equipment and the electronic equipment in the machine room.

14. The work machine according to claim 13 , wherein the hydrogen-related equipment is modularized on the partition wall.

15. the electronic device is a first electronic device, The partition is a first partition, The work machine includes: a second electronic device that is different from the first electronic device and is arranged in a position aligned horizontally with the hydrogen-related device; The work machine according to claim 13 , further comprising: a second partition wall disposed in the machine room between the hydrogen-related equipment and the second electronic equipment.

16. A hydrogen tank for storing hydrogen; A heat exchanger that exchanges heat with cooling air; Electronic equipment for operating the work machine; The machine room, a partition wall disposed between the hydrogen tank and the electronic equipment in the machine room, The hydrogen tank is disposed in the machine room upstream of the heat exchanger in a flow direction of the cooling air.

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