Work vehicle

Abstract

This work vehicle is equipped with a drive source that uses hydrogen as fuel, and is provided with an electrolysis device that uses electric power to electrolyze generated water generated from the drive source or stored water stored in a water tank.

Description

Technical Field

[0001] The present invention relates to a work vehicle.

[0002] The present invention claims priority based on Japanese Patent Application No. 2023-006101 filed on January 18, 2023, and incorporates its content herein. Background Art

[0003] Towards carbon neutrality, zero-emission of mining machinery and construction machinery is an urgent task. As one of the mechanisms for achieving zero-emission, there are fuel cell systems and hydrogen engines. For example, a fuel cell system includes a fuel cell (FC: Fuel Cell), a storage battery, and a hydrogen tank that stores hydrogen as fuel. For example, the fuel cell system is mounted on a fuel cell vehicle that travels by a driving motor. For example, the electric power charged into the storage battery is used as the driving energy when the fuel cell vehicle is in operation. For example, the regenerative electric power of the driving motor generated when the fuel cell vehicle goes downhill or decelerates is charged into the storage battery. However, depending on the capacity of the storage battery, the electric power that can be charged into the storage battery is limited. Therefore, the electric power that cannot be fully charged into the storage battery becomes losses such as heat energy. In addition, in the case of a hydrogen engine vehicle without a storage battery, all the generated energy is lost. Therefore, it is necessary to suppress energy loss.

[0004] For example, Patent Document 1 discloses a fuel cell system that includes: a moisture condensation unit that condenses moisture in the air to generate water; a filtration unit that filters the generated water; a fuel cell that uses the filtered water; and a control unit that operates the moisture condensation unit by the surplus electric power of the fuel cell. The fuel cell system is mounted on a fuel cell electric vehicle (FCEV).

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2004-206928 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] However, the filtered water is only used for humidifying the electrolyte membrane of the fuel cell unit and is not used as the driving energy of the FCEV. Therefore, there is room for improvement in suppressing energy loss.

[0010] Therefore, an object of the present invention is to provide a work vehicle capable of suppressing energy loss.

[0011] Means for Solving the Problems

[0012] In a work vehicle according to an aspect of the present invention, in a work vehicle equipped with a drive source fueled by hydrogen, the work vehicle includes an electrolysis device that electrolyzes generated water generated from the drive source or stored water stored in a water tank using electric power.

[0013] Advantages of the Invention

[0014] According to the above aspect, energy loss can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a side view of the dump truck according to the embodiment.

[0016] Figure 2 is a block diagram of the circuit configuration of the fuel cell system according to the embodiment.

[0017] Figure 3 is an explanatory diagram of the flow of electricity and the like during traveling in the fuel cell system according to the embodiment.

[0018] Figure 4 is an explanatory diagram of the flow of electricity and the like during regeneration in the fuel cell system according to the embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiment, as a work vehicle constituting a fuel cell system, a dump truck, which is a transport vehicle that travels at a work site such as a mine and transports goods, will be described.

[0020] <Dump Truck>

[0021] Figure 1 is a side view of the dump truck 2 according to the embodiment. Figure 2 is a block diagram of the circuit configuration of the fuel cell system 1 according to the embodiment.

[0022] Refer to Figure 1 and Figure 2 , the dump truck 2 is equipped with a drive source 30 (equivalent to an FC stack) fueled by hydrogen. The dump truck 2 includes an electrolysis device 40 that electrolyzes generated water generated from the drive source 30 or stored water stored in a water tank 41 using electric power.

[0023] The dump truck 2 includes: a vehicle body frame 10 equipped with a drive source 30 fueled by hydrogen, a dump body 12 (equivalent to a dump truck bed) that is rotatably coupled to the vehicle body frame 10 via a rotating portion 11 and carries a load, and a traveling device 13 that supports the vehicle body frame 10. For example, the dump truck 2 can be an unmanned dump truck that is driven in an unmanned manner without relying on the driving operation of a driver, or a manned dump truck that is driven based on the driving operation of a driver.

[0024] Hereinafter, the forward direction (front of the vehicle body), reverse direction (rear of the vehicle body), and vehicle width direction (left and right of the vehicle body) of the dump truck 2 are referred to as "front of the vehicle (one side of the vehicle front-rear direction)", "rear of the vehicle (the other side of the vehicle front-rear direction)", and "vehicle width direction", respectively. The vehicle width direction is sometimes also referred to as "left side (one side of the vehicle width direction)" or "right side (the other side of the vehicle width direction)". The right hand is referred to as the right side with respect to the direction in which the dump truck 2 advances, and the left hand is referred to as the left side with respect to the advancing direction of the dump truck 2. The vehicle up-down direction (up-down direction of the vehicle body), vehicle upper side (upper side of the vehicle body), and vehicle lower side (lower side of the vehicle body) of the dump truck 2 are simply referred to as "up-down direction", "upper side", and "lower side", respectively. In the example of the figure, the dump truck 2 is disposed on a horizontal plane (horizontal ground). The vehicle up-down direction (up-down direction of the vehicle body), vehicle upper side (upper side of the vehicle body), and vehicle lower side (lower side of the vehicle body) of the dump truck 2 coincide with the up-down direction (vertical direction), vertically upper side, and vertically lower side, respectively, in the state where the dump truck 2 is disposed on the horizontal plane.

[0025] The body frame 10 extends in the vehicle front-rear direction. The body frame 10 supports the unloading vehicle body 12 via a rotating portion 11 so as to be rotatable. The rotating portion 11 is a portion including a shaft portion (corresponding to the rotation center axis of the unloading vehicle body 12) extending in the vehicle width direction on the body frame 10. The body frame 10 is supported by the traveling device 13.

[0026] The unloading vehicle body 12 is rotatably coupled to the body frame 10 via the rotating portion 11. The unloading vehicle body 12 is a member for loading goods (corresponding to a carriage). At least a part of the unloading vehicle body 12 is disposed at a position above the body frame 10. The unloading vehicle body 12 can perform an unloading operation and a lowering operation.

[0027] The unloading operation is an operation of separating the unloading vehicle body 12 from the body frame 10 and tilting it in the unloading direction. The unloading direction is the rear of the body frame 10. In the embodiment, the unloading operation includes raising the front end portion of the unloading vehicle body 12 and tilting the unloading vehicle body 12 backward. By the unloading operation, the loading surface of the unloading vehicle body 12 faces backward and tilts downward.

[0028] The lowering operation is an operation of bringing the unloading vehicle body 12 closer to the body frame 10. The lowering operation is an operation in the opposite direction to the unloading operation. In the embodiment, the lowering operation includes lowering the front end portion of the unloading vehicle body 12.

[0029] By the unloading operation and the lowering operation, the unloading vehicle body 12 is adjusted to an unloading posture and a loading posture. The unloading posture is a posture in which the unloading vehicle body 12 is raised. The loading posture is a posture in which the unloading vehicle body 12 is lowered. In Figure 1 the example, the unloading vehicle body 12 in the loading posture is shown by a solid line, and the unloading vehicle body 12 in the unloading posture is shown by a double-dot dash line.

[0030] For example, in the case of carrying out the dumping operation, the dumping vehicle body 12 performs a dumping action in such a way that it changes from the loading posture to the dumping posture. When the goods are loaded on the dumping vehicle body 12, the goods are discharged rearward from the rear end portion of the dumping vehicle body 12 by the dumping action. On the other hand, in the case of carrying out the loading operation, the dumping vehicle body 12 is adjusted to the loading posture.

[0031] The dumping vehicle body 12 is provided with a protection device 16 that protects the cab 15 from above. The protection device 16 is arranged to cover the cab 15 from above when the dumping vehicle body 12 is in the loading posture. The protection device 16 is provided on the front end side of the dumping vehicle body 12. The protection device 16 is arranged at a position above the cab 15. The protection device 16 extends in the vehicle width direction. For example, the cab 15 is arranged at a position on the left side of the vehicle relative to the center in the vehicle width direction.

[0032] The cab 15 is supported by a platform 17. The platform 17 is provided above the front portion of the vehicle body frame 10. The platform 17 is provided to ensure a footrest when the operator gets on and off the cab 15. The platform 17 is provided to ensure a footrest when maintaining the mounted equipment of the dump truck 2. The platform 17 is arranged at a position below the protection device 16. The platform 17 is arranged at a position above the wheels 21 and 22. The platform 17 extends in the vehicle width direction. The platform 17 is formed in a plate shape parallel to the vehicle longitudinal direction and the vehicle width direction.

[0033] The traveling device 13 supports the vehicle body frame 10. The traveling device 13 makes the dump truck 2 travel. The traveling device 13 makes the dump truck 2 move forward or backward. At least a part of the traveling device 13 is arranged at a position below the vehicle body frame 10. The traveling device 13 includes a plurality of wheels 21 and 22. The plurality of wheels 21 and 22 include front wheels 21 and rear wheels 22 arranged behind the front wheels 21.

[0034] The front wheels 21 are steering wheels for changing the traveling direction of the dump truck 2. A pair of left and right front wheels 21 are arranged at intervals in the vehicle width direction via the front portion of the vehicle body frame 10. One front wheel 21 is provided on each of the left and right sides (two in total).

[0035] The rear wheels 22 are drive wheels driven by a drive source 30. A pair of left and right rear wheels 22 are arranged at intervals in the vehicle width direction via the rear portion of the vehicle body frame 10. Two rear wheels 22 are provided on each of the left and right sides (four in total).

[0036] <Fuel cell system>

[0037] Figure 2 is a block diagram of the circuit structure of the fuel cell system 1 of the embodiment.Figure 3 It is an explanatory diagram of the flow of electricity, etc. during the running of the fuel cell system 1 of the embodiment. Figure 4 It is an explanatory diagram of the flow of electricity, etc. during regeneration in the fuel cell system 1 of the embodiment. In the figure, the dotted arrow represents the current, the dashed arrow represents the flow of oxygen, the solid arrow represents the flow of hydrogen, and the dash-dotted arrow represents the flow of generated water (water).

[0038] Refer to together Figures 2 to 4 , the fuel cell system 1 (an example of the system) includes a drive source 30 (equivalent to the FC stack), a hydrogen tank 31, a running motor 35, a storage battery 36, an electrolysis device 40, a water tank 41, a gas-liquid separation device 45, a water purification unit 46, and a pump 51 (equivalent to the recirculation pump). For example, the components of the fuel cell system 1 are mounted on the vehicle body frame 10.

[0039] The drive source 30 is a fuel cell (FC) that generates electricity by chemically reacting hydrogen as the fuel gas and oxygen as the oxidizing gas. For example, the fuel cell has a stack structure formed by stacking a plurality of unit cells. For example, the fuel cell generates electricity using oxygen contained in external air. It should be noted that the fuel cell may also be supplied with oxygen-containing air through an oxidizing gas supply device (not shown).

[0040] The hydrogen tank 31 is a tank for storing hydrogen. For example, the hydrogen tank 31 preferably has a cylindrical shape. In Figure 2 the example, one hydrogen tank 31 is shown. It should be noted that the shape and number of the hydrogen tank 31 are not limited to the above. For example, the hydrogen tank 31 may also be flat. For example, the number of the hydrogen tank 31 may also be two or more. For example, the shape and number of the hydrogen tank 31 can be changed according to the design specifications.

[0041] The running motor 35 is a motor for driving the dump truck 2 to run. The running motor 35 is electrically connected to the drive source 30. The running motor 35 is connected to the rear wheels 22 of the running device 13. The rotational force generated by the running motor 35 is transmitted to the rear wheels 22 of the running device 13.

[0042] For example, the storage battery 36 is a secondary battery such as a lithium-ion storage battery. The storage battery 36 is electrically connected to the running motor 35. For example, the electric power charged into the storage battery 36 is used as the driving energy when the dump truck 2 runs. The storage battery 36 stores the regenerative electric power of the running motor 35 generated when the dump truck 2 goes downhill or decelerates. It should be noted that the storage battery 36 may also store the electric power generated by the drive source 30.

[0043] The electrolysis device 40 uses electricity to electrolyze the generated water produced from the drive source 30 or the stored water stored in the water tank 41. By electrolyzing water with the electrolysis device 40, hydrogen and oxygen are generated. In the present embodiment, the hydrogen generated by the electrolysis device 40 is used as fuel for the drive source 30. On the other hand, the generated oxygen is discharged to the outside.

[0044] The electrolysis device 40 is electrically connected to the travel motor 35. The electrolysis device 40 uses the regenerative power of the travel motor 35 generated when the dump truck 2 is going downhill or decelerating as electricity. The electrolysis device 40 uses the remaining power of the regenerative power generated by the travel motor 35 that is not charged to the storage battery 36 as electricity.

[0045] For example, information related to the power that can be charged to the storage battery 36 (hereinafter also referred to as "battery capacity") and the regenerative power generated by the travel motor 35 (hereinafter also referred to as "motor power generation") can also be input to a controller (not shown). For example, the controller can also determine that the regenerative power generated by the travel motor 35 is not charged to the storage battery 36 when the motor power generation exceeds the battery capacity. For example, the controller can also calculate the amount obtained by subtracting the battery capacity (specifically, the remaining capacity of the storage battery 36) from the motor power generation as the remaining power.

[0046] The water tank 41 is a tank for storing water. For example, the water tank 41 can also be mounted on the electrolysis device 40. It should be noted that the water tank 41 can also be provided outside the electrolysis device 40. For example, the installation method of the water tank 41 can be changed according to the design specifications.

[0047] The gas-liquid separation device 45 separates the remaining hydrogen in the hydrogen supplied to the drive source 30 that is not utilized by the drive source 30 from the generated water generated from the drive source 30. The generated water separated by the gas-liquid separation device 45 is supplied to the water tank 41.

[0048] For example, the water purification unit 46 is a filter for purifying the water decomposed in the electrolysis device 40. For example, the water purification unit 46 can also be composed of a dust filter, a chemical filter, a catalyst, etc. For example, the composition method of the water purification unit 46 can be changed according to the design specifications.

[0049] The water purification unit 46 purifies the generated water or the stored water. In the present embodiment, the water purification unit 46 purifies the generated water separated by the gas-liquid separation device 45. The electrolysis device 40 electrolyzes the purified water purified by the water purification unit 46.

[0050] In the example of the figure, the water purification unit 46 is provided upstream of the electrolysis device 40. Specifically, the water purification unit 46 is provided in the middle of the pipe connecting the gas-liquid separation device 45 and the water tank 41. It should be noted that the water purification unit 46 can also be provided inside the electrolysis device 40. For example, the water purification unit 46 can also be provided downstream of the water tank 41. For example, the installation method of the water purification unit 46 can be changed according to the design specifications.

[0051] The fuel cell system 1 further includes: a hydrogen supply pipe 32 for supplying hydrogen stored in the hydrogen tank 31 to the drive source 30; and a hydrogen circulation mechanism 50 for circulating the remaining hydrogen that is not utilized by the drive source 30 in the hydrogen supplied to the drive source 30 between the hydrogen supply pipe 32 and the drive source 30.

[0052] A portion of the hydrogen supply pipe 32 on the side opposite to the portion connected to the hydrogen tank 31 is connected to the drive source 30. For example, the hydrogen supply pipe 32 is preferably composed of a high-pressure metal pipe capable of withstanding high-pressure hydrogen (for example, about 70 MPa). It should be noted that a pressure reducing valve for reducing the pressure of high-pressure hydrogen can also be provided in the middle of the hydrogen supply pipe 32.

[0053] The pump 51 is a component of the hydrogen circulation mechanism 50. The hydrogen circulation mechanism 50 includes a pump 51 that conveys the pressurized hydrogen obtained by pressurizing the remaining hydrogen to the hydrogen supply pipe 32, an upstream pipe 52 and a downstream pipe 53 through which the remaining hydrogen from the drive source 30 flows, and a confluence pipe 56 through which the hydrogen generated by the electrolysis device 40 flows.

[0054] The upstream pipe 52 is a pipe connecting the drive source 30 and the pump 51. The upstream pipe 52 is provided upstream of the pump 51. The confluence pipe 56 is a pipe connecting the electrolysis device 40 and the upstream pipe 52. The confluence pipe 56 supplies the water path generated by the electrolysis device 40 to the upstream pipe 52. The hydrogen generated by the electrolysis device 40 (for example, hydrogen at normal temperature and pressure) is supplied to the upstream pipe 52 through the confluence pipe 56. The remaining hydrogen from the drive source 30 and the hydrogen generated by the electrolysis device 40 (both are low-pressure hydrogen before being pressurized by the pump 51) flow in the upstream pipe 52. For example, a gas-liquid separation device 45 can also be provided in the middle of the upstream pipe 52.

[0055] The downstream pipe 53 is a pipe connecting the hydrogen supply pipe 32 and the pump 51. The downstream pipe 53 is provided downstream of the pump 51. The pressurized hydrogen pressurized by the pump 51 in the remaining hydrogen from the drive source 30 flows in the downstream pipe 53. Therefore, the pressure of the pressurized hydrogen flowing in the downstream pipe 53 is higher than the pressure of the hydrogen flowing in the upstream pipe 52.

[0056] The fuel cell system 1 further includes a hydrogen reflux mechanism 55 that refluxes the surplus hydrogen in the hydrogen supplied to the drive source 30 and not utilized by the drive source 30 back to the hydrogen supply pipe 32. The upstream pipe 52 and the downstream pipe 53 are components of the hydrogen reflux mechanism 55. For example, the hydrogen reflux mechanism 55 may also be constituted by at least a part of the hydrogen circulation mechanism 50.

[0057] It should be noted that a switching valve for switching the flow of various fluids may be provided in the middle of various pipes. For example, the switching valve may be provided at a branch portion of the pipe. For example, the controller may control the switching valve in such a way as to switch the flow of various fluids according to the driving state of the dump truck 2 (e.g., during driving, during regeneration, etc.).

[0058] <Flow of electricity, etc. during driving>

[0059] Next, with reference to Figure 3 etc., an example of the flow of electricity, etc. during the driving of the dump truck 2 will be described.

[0060] Hydrogen in the hydrogen tank 31 is supplied to the drive source 30. The drive source 30 causes hydrogen as a fuel gas to chemically react with oxygen as an oxidizing gas to generate electricity. The drive source 30 generates electricity using oxygen contained in external air.

[0061] Through the gas-liquid separation device 45, the generated water generated from the drive source 30 is separated from the surplus hydrogen in the hydrogen supplied to the drive source 30 and not utilized by the drive source 30. The generated water separated by the gas-liquid separation device 45 is supplied (stored) to the water tank 41. The surplus hydrogen separated by the gas-liquid separation device 45 is supplied to the drive source 30 again as fuel for the drive source 30 through the hydrogen circulation mechanism 50 including a pump 51, etc.

[0062] The electric power generated by the drive source 30 (hereinafter also referred to as "FC output") is used as the driving energy of the traveling motor 35. By driving the traveling motor 35, the rear wheels 22 (tires) as drive wheels rotate. Thereby, the dump truck 2 travels. The electric power charged into the storage battery 36 is used as the driving energy of the traveling motor 35 during the power operation of the dump truck 2 (e.g., during full-load driving, uphill, etc.). The shortage of the FC output is supplemented by discharging the storage battery 36.

[0063] <Flow of electricity, etc. during regeneration>

[0064] Next, with reference to Figure 4 etc., an example of the flow of electricity, etc. during the regeneration of the dump truck 2 (e.g., during downhill or deceleration) will be described.

[0065] The storage battery 36 is charged with the regenerative power of the traveling motor 35 generated when the dump truck 2 goes downhill or decelerates. The remaining power of the regenerative power generated by the traveling motor 35 that is not charged to the storage battery 36 is used as the power for the electrolysis device 40.

[0066] In the electrolysis device 40, the remaining power is used to electrolyze the water stored in the water tank 41 (the generated water separated by the gas-liquid separation device 45). Through the electrolysis of water, hydrogen and oxygen are generated. The hydrogen generated by the electrolysis device 40 is supplied to the drive source 30 through the confluence pipe 56 or the like and is used as the fuel for the drive source 30. On the other hand, the generated oxygen is discharged to the outside.

[0067] <Effect>

[0068] As described above, the dump truck 2 of the present embodiment is equipped with a drive source 30 that uses hydrogen as fuel. The dump truck 2 is provided with an electrolysis device 40 that uses electricity to electrolyze the generated water generated from the drive source 30 or the stored water stored in the water tank 41.

[0069] According to this structure, through the power used by the electrolysis device 40, the generated water generated from the drive source 30 or the stored water stored in the water tank 41 is electrolyzed, thereby generating hydrogen. The generated hydrogen can be used as the driving energy of the dump truck 2. Therefore, energy loss can be suppressed.

[0070] In the present embodiment, the hydrogen generated by the electrolysis device 40 is used as the fuel for the drive source 30.

[0071] According to this structure, the generated hydrogen can be used as the fuel for the drive source 30. Therefore, the loss of the fuel of the drive source 30 can be suppressed. For example, the consumption of hydrogen in the hydrogen tank 31 can be reduced.

[0072] In the present embodiment, the dump truck 2 is further provided with a traveling motor 35 for driving the dump truck 2. The electrolysis device 40 uses the regenerative power of the traveling motor 35 generated when the dump truck 2 goes downhill or decelerates as power.

[0073] According to this structure, the regenerative power of the traveling motor 35 can be effectively used as the power for electrolysis.

[0074] In the present embodiment, the dump truck 2 is further provided with a storage battery 36 for storing the regenerative power generated by the traveling motor 35. The electrolysis device 40 uses the remaining power of the regenerative power generated by the traveling motor 35 that is not charged to the storage battery 36 as power.

[0075] According to this structure, the remaining power that is not charged to the storage battery 36 can be effectively used as the power for electrolysis. Therefore, the loss of the remaining power can be suppressed.

[0076] In this embodiment, the dump truck 2 further includes a water purification unit 46 that purifies generated water or stored water. The electrolysis device 40 electrolyzes the purified water purified by the water purification unit 46.

[0077] According to this structure, by electrolyzing purified water, hydrogen of higher purity is generated. Therefore, hydrogen of higher purity can be used as fuel for the drive source 30.

[0078] In this embodiment, the dump truck 2 further includes: a hydrogen tank 31 that stores hydrogen; a hydrogen supply pipe 32 that supplies the hydrogen stored in the hydrogen tank 31 to the drive source 30; and a hydrogen circulation mechanism 50 that circulates the remaining hydrogen that is not used by the drive source 30 in the hydrogen supplied to the drive source 30 between the hydrogen supply pipe 32 and the drive source 30.

[0079] According to this structure, the remaining hydrogen that is not used by the drive source 30 can be used again as fuel for the drive source 30. Therefore, the loss of fuel for the drive source 30 can be more effectively suppressed. Therefore, the consumption of hydrogen in the hydrogen tank 31 can be more effectively reduced.

[0080] In this embodiment, the hydrogen circulation mechanism 50 includes: a pump 51 that conveys pressurized hydrogen to the hydrogen supply pipe 32; and an upstream pipe 52 that connects the drive source 30 and the pump 51 and allows the remaining hydrogen from the drive source 30 to flow. The hydrogen generated by the electrolysis device 40 is supplied to the upstream pipe 52.

[0081] For example, when the hydrogen generated by the electrolysis device 40 is directly supplied to the hydrogen supply pipe 32, it is necessary to increase the pressure of the hydrogen generated by the electrolysis device 40. In contrast, according to this structure, the hydrogen generated by the electrolysis device 40 is supplied to the upstream pipe 52, so there is no need to increase the pressure of the hydrogen generated by the electrolysis device 40. That is, no energy is required to increase the pressure of the hydrogen generated by the electrolysis device 40. Therefore, the loss of energy can be more effectively suppressed.

[0082] In this embodiment, the dump truck 2 further includes a water tank 41 and a gas-liquid separation device 45. The gas-liquid separation device 45 separates the remaining hydrogen that is not used by the drive source 30 in the hydrogen supplied to the drive source 30 from the generated water generated by the drive source 30. The generated water separated by the gas-liquid separation device 45 is supplied to the water tank 41.

[0083] According to this structure, the generated water separated by the gas-liquid separation device 45 can be stored in the water tank 41. Therefore, the consumption of the stored water in the water tank 41 can be more effectively reduced. For example, by effectively using the generated water as water for electrolysis, water supply from the outside can be made unnecessary.

[0084] In the present embodiment, the dump truck 2 further includes: a hydrogen tank 31 that stores hydrogen; a hydrogen supply pipe 32 that supplies the hydrogen stored in the hydrogen tank 31 to the drive source 30; and a hydrogen reflux mechanism 55 that refluxes the surplus hydrogen that is not utilized by the drive source 30 among the hydrogen supplied to the drive source 30 back to the hydrogen supply pipe 32.

[0085] According to this structure, by refluxing the surplus hydrogen that is not utilized by the drive source 30 back to the hydrogen supply pipe 32, it is possible to utilize it again as fuel for the drive source 30. Therefore, it is possible to more effectively suppress the loss of fuel for the drive source 30. As a result, it is possible to more effectively reduce the consumption of hydrogen in the hydrogen tank 31.

[0086] <Modification Example>

[0087] In the above-described embodiment, an example in which the hydrogen generated by the electrolysis device is used as fuel for the drive source has been described, but it is not limited thereto. For example, the hydrogen generated by the electrolysis device may be supplied to the hydrogen tank. For example, the method of utilizing the hydrogen generated by the electrolysis device can be changed according to the design specifications.

[0088] In the above-described embodiment, an example in which the work vehicle further includes a traveling motor for driving the work vehicle has been described, but it is not limited thereto. For example, the work vehicle may not include a traveling motor. For example, in the case where the drive source is a hydrogen engine, the work vehicle may also travel by the drive of the hydrogen engine. For example, the installation method of the traveling motor can be changed according to the design specifications.

[0089] In the above-described embodiment, an example in which the electrolysis device uses the regenerative power of the traveling motor generated when the work vehicle is going downhill or decelerating as power has been described, but it is not limited thereto. For example, the electrolysis device may not use the regenerative power of the traveling motor. For example, the electrolysis device may also use the power generated by the drive source. For example, the electrolysis device may also use the power charged to the storage battery. For example, the method of the power used for electrolysis can be changed according to the design specifications.

[0090] In the above-described embodiment, an example in which the work vehicle further includes a storage battery that stores the regenerative power generated by the traveling motor has been described, but it is not limited thereto. For example, in the case where the drive source is a hydrogen engine, the work vehicle may not include a storage battery. For example, the installation method of the storage battery can be changed according to the design specifications.

[0091] In the above-described embodiments, an example in which the electrolysis device uses the surplus power that has not been charged into the storage battery from the regenerative power generated by the electric driving motor as power has been described, but it is not limited thereto. For example, the electrolysis device may not use the surplus power that has not been charged into the storage battery. For example, the electrolysis device may use a part of the regenerative power of the driving motor. For example, the regenerative power of the driving motor may be used for both the power used by the electrolysis device and the charging of the storage battery. For example, the utilization method of the regenerative power or the surplus power of the driving motor can be changed according to the design specifications.

[0092] In the above-described embodiments, an example in which the work vehicle further includes a water purification unit that purifies the generated water or the stored water has been described, but it is not limited thereto. For example, the work vehicle may not include a water purification unit. For example, the generated water generated from the drive source or the stored water stored in the water tank may be directly electrolyzed. For example, the installation method of the water purification unit can be changed according to the design specifications.

[0093] In the above-described embodiments, an example in which the work vehicle further includes a hydrogen tank that stores hydrogen, a hydrogen supply pipe for supplying the hydrogen stored in the hydrogen tank to the drive source, and a hydrogen circulation mechanism that circulates the surplus hydrogen that has not been utilized by the drive source in the hydrogen supplied to the drive source between the hydrogen supply pipe and the drive source has been described, but it is not limited thereto. For example, the work vehicle may not include at least one of the hydrogen tank, the hydrogen supply pipe, and the hydrogen circulation mechanism. For example, the installation method of the hydrogen tank, the hydrogen supply pipe, and the hydrogen circulation mechanism can be changed according to the design specifications.

[0094] In the above-described embodiments, an example in which the hydrogen circulation mechanism includes a pump that transports pressurized hydrogen to the hydrogen supply pipe, an upstream pipe that connects the drive source and the pump and through which the surplus hydrogen from the drive source flows, and the hydrogen generated by the electrolysis device is supplied to the upstream pipe has been described, but it is not limited thereto. For example, the hydrogen generated by the electrolysis device may also be supplied to the hydrogen supply pipe. For example, the supply method of the hydrogen generated by the electrolysis device can be changed according to the design specifications.

[0095] In the above-described embodiments, an example in which the work vehicle further includes a water tank and a gas-liquid separation device that separates the surplus hydrogen that has not been utilized by the drive source in the hydrogen supplied to the drive source from the generated water generated from the drive source has been described, but it is not limited thereto. For example, the work vehicle may not include at least one of the water tank and the gas-liquid separation device. For example, the installation method of the water tank and the gas-liquid separation device can be changed according to the design specifications.

[0096] In the above-described embodiment, an example in which the generated water separated by the gas-liquid separation device is supplied to the water tank has been described, but it is not limited thereto. For example, the generated water separated by the gas-liquid separation device may not be supplied to the water tank. For example, the generated water separated by the gas-liquid separation device may be discharged to the outside. For example, the utilization method of the generated water separated by the gas-liquid separation device can be changed according to the design specifications.

[0097] In the above-described embodiment, an example in which the work vehicle further includes a hydrogen tank for storing hydrogen, a hydrogen supply pipe for supplying the hydrogen stored in the hydrogen tank to the drive source, and a hydrogen reflux mechanism for refluxing the surplus hydrogen that is not utilized by the drive source in the hydrogen supplied to the drive source to the hydrogen supply pipe has been described, but it is not limited thereto. For example, the work vehicle may not include at least one of the hydrogen tank, the hydrogen supply pipe, and the hydrogen reflux mechanism. For example, the arrangement of the hydrogen tank, the hydrogen supply pipe, and the hydrogen reflux mechanism can be changed according to the design specifications.

[0098] In the above-described embodiment, an example in which the drive source is a fuel cell (FC) that generates electricity by chemically reacting hydrogen as a fuel gas with oxygen as an oxidizing gas has been described, but it is not limited thereto. For example, the drive source may be a hydrogen engine, which is an internal combustion engine using hydrogen as fuel. For example, the drive source may include a fuel cell and a hydrogen engine. For example, the configuration of the drive source can be changed according to the design specifications.

[0099] In the above-described embodiment, an example in which the work vehicle is a dump truck has been described, but it is not limited thereto. For example, the work vehicle may be other work vehicles such as an excavator, a bulldozer, or a wheel loader. For example, the type of the work vehicle can be changed according to the design specifications.

[0100] The above has described the embodiments of the present invention, but the present invention is not limited thereto. Without departing from the gist of the present invention, additions, omissions, substitutions, and other changes to the structure can be made, and the above embodiments can also be appropriately combined.

[0101] (Supplementary Note 1)

[0102] A work vehicle equipped with a drive source using hydrogen as fuel, wherein,

[0103] The work vehicle includes an electrolysis device that electrolyzes the generated water generated from the drive source or the stored water stored in a water tank using electricity.

[0104] (Supplementary Note 2)

[0105] According to the work vehicle described in Supplementary Note 1, wherein,

[0106] The hydrogen generated by the electrolysis device is used as fuel for the drive source.

[0107] (Supplementary Note 3)

[0108] The work vehicle according to Supplementary Note 1 or 2, wherein,

[0109] the work vehicle further includes a traveling motor for causing the work vehicle to travel,

[0110] the electrolysis device uses the regenerative power of the traveling motor generated when the work vehicle is going downhill or decelerating as the power.

[0111] (Supplementary Note 4)

[0112] The work vehicle according to Supplementary Note 3, wherein,

[0113] the work vehicle further includes a storage battery for storing the regenerative power generated by the traveling motor,

[0114] the electrolysis device uses the remaining power of the regenerative power generated by the traveling motor that has not been charged to the storage battery as the power.

[0115] (Supplementary Note 5)

[0116] The work vehicle according to any one of Supplementary Notes 1 to 4, wherein,

[0117] the work vehicle further includes a water purification unit for purifying the generated water or the stored water,

[0118] the electrolysis device electrolyzes the purified water purified by the water purification unit.

[0119] (Supplementary Note 6)

[0120] The work vehicle according to any one of Supplementary Notes 1 to 5, wherein,

[0121] the work vehicle further includes:

[0122] a hydrogen tank for storing hydrogen;

[0123] a hydrogen supply pipe for supplying the hydrogen stored in the hydrogen tank to the drive source; and

[0124] a hydrogen circulation mechanism for circulating the remaining hydrogen that has not been utilized by the drive source in the hydrogen supplied to the drive source between the hydrogen supply pipe and the drive source.

[0125] (Supplementary Note 7)

[0126] The work vehicle according to Supplementary Note 6, wherein,

[0127] the hydrogen circulation mechanism includes:

[0128] A pump that delivers pressurized hydrogen to the hydrogen supply pipe; and

[0129] An upstream pipe that connects the drive source to the pump and allows the remaining hydrogen from the drive source to flow;

[0130] Hydrogen generated by the electrolysis device is supplied to the upstream pipe.

[0131] (Appendix Note 8)

[0132] The work vehicle according to any one of Appendix Notes 1 to 7, wherein

[0133] The work vehicle further includes:

[0134] The water tank; and

[0135] A gas-liquid separation device that separates the remaining hydrogen not utilized by the drive source from the hydrogen supplied to the drive source and the generated water generated from the drive source,

[0136] The generated water separated by the gas-liquid separation device is supplied to the water tank.

[0137] (Appendix Note 9)

[0138] The work vehicle according to any one of Appendix Notes 1 to 8, wherein

[0139] The work vehicle further includes:

[0140] A hydrogen tank that stores hydrogen;

[0141] A hydrogen supply pipe for supplying hydrogen stored in the hydrogen tank to the drive source; and

[0142] A hydrogen reflux mechanism that refluxes the remaining hydrogen not utilized by the drive source in the hydrogen supplied to the drive source back to the hydrogen supply pipe.

[0143] Explanation of reference numerals:

[0144] 2... dump truck (work vehicle); 30... drive source; 31... hydrogen tank; 32... hydrogen supply pipe; 35... travel motor; 36... storage battery; 40... electrolysis device; 41... water tank; 45... gas-liquid separation device; 46... water purification unit; 50... hydrogen circulation mechanism; 51... pump; 52... upstream pipe; 55... hydrogen reflux mechanism.

Claims

1. An operating vehicle equipped with a drive source fueled by hydrogen, wherein, the operating vehicle includes an electrolysis device that electrolyzes generated water produced from the drive source or stored water stored in a water tank using electricity.

2. The operating vehicle according to claim 1, wherein, the hydrogen generated by the electrolysis device is used as fuel for the drive source.

3. The operating vehicle according to claim 1 or 2, wherein, the operating vehicle further includes a traveling motor for driving the operating vehicle, the electrolysis device uses the regenerative power of the traveling motor generated when the operating vehicle is going downhill or decelerating as the electricity.

4. The operating vehicle according to claim 3, wherein, the operating vehicle further includes a storage battery for storing the regenerative power generated by the traveling motor, the electrolysis device uses the remaining power of the regenerative power generated by the traveling motor that has not been charged to the storage battery as the electricity.

5. The operating vehicle according to claim 1 or 2, wherein, the operating vehicle further includes a water purification unit for purifying the generated water or the stored water, the electrolysis device electrolyzes the purified water purified by the water purification unit.

6. The operating vehicle according to claim 1 or 2, wherein, the operating vehicle further includes: a hydrogen tank for storing hydrogen; a hydrogen supply pipe for supplying the hydrogen stored in the hydrogen tank to the drive source; and a hydrogen circulation mechanism for circulating the remaining hydrogen that has not been utilized by the drive source among the hydrogen supplied to the drive source between the hydrogen supply pipe and the drive source.

7. The operating vehicle according to claim 6, wherein, the hydrogen circulation mechanism includes: a pump for delivering pressurized hydrogen to the hydrogen supply pipe; and an upstream pipe for connecting the drive source and the pump and allowing the remaining hydrogen from the drive source to flow, the hydrogen generated by the electrolysis device is supplied to the upstream pipe.

8. The operating vehicle according to claim 1 or 2, wherein, the operating vehicle further includes: the water tank; and a gas-liquid separation device for separating the remaining hydrogen that has not been utilized by the drive source in the hydrogen supplied to the drive source from the generated water generated from the drive source, the generated water separated by the gas-liquid separation device is supplied to the water tank.

9. The operating vehicle according to claim 1 or 2, wherein, the operating vehicle further includes: a hydrogen tank for storing hydrogen; a hydrogen supply pipe for supplying the hydrogen stored in the hydrogen tank to the drive source; and a hydrogen reflux mechanism for refluxing the remaining hydrogen that has not been utilized by the drive source in the hydrogen supplied to the drive source to the hydrogen supply pipe.

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