tractor

Abstract

To provide a working machine including a cabin, capable of achieving the drive by a fuel cell instead of an internal combustion engine that uses a fossil fuel, as well as, protecting a hydrogen tank for supplying the fuel from a fall, and the like of the working machine and suppressing an increase in the temperature of the hydrogen tank.SOLUTION: A tractor according to the invention comprises: a vehicle body; a drive motor; a PTO shaft rotated by power transmitted from the drive motor; a fuel cell that is disposed in a front part of the vehicle and supplies electric power to the drive motor; a cabin that is disposed behind the fuel battery; and multiple hydrogen tanks disposed in an upper portion of the cabin. The multiple hydrogen tanks are aligned directed from a front side to a rear side of the cabin.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a work machine such as an agricultural machine or a construction machine, such as a tractor, and more particularly to a tractor provided with a cabin that houses a driver's seat. [Background technology]

[0002] Generally, a conventional tractor equipped with a cabin has a bonnet at the front of the vehicle body, which houses the engine, radiator, fuel tank, battery, etc., and a cabin at the rear of the vehicle body, which houses the driver's seat, control device, etc. The fuel tank is housed in the bonnet together with the engine, which is the driving source, making the entire tractor and the fuel supply path compact. Patent Document 1 is an example of a document that discloses a tractor equipped with an engine and a cabin.

[0003] Incidentally, in the recent automobile industry, from the viewpoint of protecting the global environment by preventing global warming, fuel cell vehicles (FCVs) that do not emit harmful substances such as carbon dioxide by using gaseous fuels such as hydrogen gas instead of internal combustion engines that use fossil fuels have been developed. In these fuel cell vehicles, for example, a fuel cell is mounted under the front seats, a hydrogen tank is stored behind or under the rear seats, and a drive motor is located near the drive wheels (Patent Document 2). As the hydrogen tank, a high-pressure hydrogen tank reinforced with carbon fiber reinforced plastic (CFRP) is often used so that it can withstand a high pressure of 70 MPa. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-00899 [Patent Document 2] JP 2010-23550 A Summary of the Invention [Problem to be solved by the invention]

[0005] Due to the strength of carbon fiber reinforced resin, the high-pressure hydrogen tanks of fuel cell vehicles are required by law to be kept at 85°C or lower. It is also known that when hydrogen gas is rapidly filled into a high-pressure hydrogen tank at high pressure, the temperature of the filled hydrogen gas in the high-pressure hydrogen tank rises sharply.

[0006] As an example of a working machine, if a fuel cell is installed on an agricultural tractor, it is conceivable to place a high-pressure hydrogen tank inside the hood along with heat-generating components such as the fuel cell. However, agricultural tractors generally operate continuously for long periods of time in conditions with high outside temperatures, and the temperature inside the hood can reach nearly 60°C. Therefore, if hydrogen gas is refilled immediately after continuous use, the temperature inside the high-pressure hydrogen tank could reach 85°C or higher.

[0007] The present invention has been made to solve these problems with the conventional technology, and has as its object to provide a tractor or other work machine that not only helps to prevent global warming, but also protects the hydrogen tank from vibration and tipping over of the work machine and prevents the hydrogen tank from becoming too hot. [Means for solving the problem]

[0008] A tractor according to one aspect of the present invention includes a vehicle body, a drive motor, a PTO shaft that rotates by power transmission from the drive motor, a fuel cell arranged in the front of the vehicle body and supplies power to the drive motor, a driver's seat arranged behind the fuel cell, and a power steering unit arranged in the front of the vehicle body. and a plurality of hydrogen tanks arranged above the vertical seats, the plurality of hydrogen tanks being aligned from the front to the rear of the cockpit.

[0009] The tractor may also include a steering device disposed in front of the driver's seat, and at least one of the multiple hydrogen tanks may be disposed above the steering device.

[0010] The fuel cell may also be disposed forward of the cockpit and the control device.

[0011] The tractor may also include a ceiling wall located between the multiple hydrogen tanks and the driver's seat.

[0012] Each of the plurality of hydrogen tanks may have a mouthpiece, and each of the plurality of hydrogen tanks may be arranged with the mouthpiece facing in a direction perpendicular to the front-to-rear direction.

[0013] Additionally, each of the plurality of hydrogen tanks may be formed in a cylindrical shape and extend in a direction perpendicular to the front-rear direction. Effect of the Invention

[0014] With the work machine of the present invention, it is possible to secure ample space for the placement of a high-pressure hydrogen tank, easily suppress the temperature rise of the high-pressure hydrogen tank, and also to protect the hydrogen tank from vibration and tipping over of the work machine. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic side view of an agricultural tractor 1 according to a first embodiment of the present invention. [Diagram 2] 2 is a schematic cross-sectional view of the cabin 5 of the tractor 1 taken along line II-II in FIG. [Diagram 3] FIG. 2 is a plan view of the cabin 5 of FIG. [Figure 4] FIG. 2 is a schematic vertical cross-sectional view of the hydrogen tank of FIG. 1. [Diagram 5] FIG. 4 is a schematic side view of an agricultural tractor 1A according to a second embodiment of the present invention. [Figure 6] FIG. 11 is a schematic side view of an agricultural tractor 1B according to a third embodiment of the present invention. [Figure 7] 1. FIG. 4 is a cross-sectional view of a support mechanism for the hydrogen tank 25 of FIG. 1 according to a modified example of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, similar components are denoted by the same reference numerals and the description thereof will be omitted.

[0017] [First embodiment] 1 to 4 show an agricultural tractor (working machine) 1 and its components according to a first embodiment of the present invention. In this embodiment, the vehicle travel direction (forward arrow) is defined as the "forward" of the tractor 1 and each component for the tractor, the opposite direction to the vehicle travel direction is defined as the rear, and the left and right directions as seen by an operator riding on the vehicle are defined as the "left and right" of the tractor 1 and each component for the tractor. Also, the horizontal direction perpendicular to the front-rear direction of the vehicle body will be described as the width direction of the tractor 1.

[0018] Fig. 1 is a schematic side view of an agricultural tractor 1 according to a first embodiment of the present invention. The tractor 1 in Fig. 1 shows the left side of the entire tractor. The tractor 1 in Fig. 1 is configured to include a body 2 that is long in the front-rear direction, a bonnet 3 provided at the front of the body 2, a cabin 5 mounted at the rear of the body 2 and accommodating a driver's seat 4 where an operator sits, a wheeled traveling device 6 that supports the body 2 so that it can travel, a drive unit 7 that drives the traveling device 6, a three-point linkage mechanism 9 provided at the rear end of the body 2, and a PTO shaft (power take-off shaft) 10 that transmits power from the drive unit 7.

[0019] 1 includes a pair of left and right rear wheels 11 and a pair of left and right front wheels 12, and the upper parts of the rear wheels 11 are covered with fenders 13. Here, the traveling device 6 is a two-wheel drive / four-wheel switchable four-wheel drive system, and is configured to be switchable between a two-wheel drive state in which only the rear wheels 11 are driven, and a four-wheel drive state in which the rear wheels 11 and the front wheels 12 are driven. Note that the present invention is also applicable to tractors equipped with a two-wheel drive system in which only the rear wheels are driven, or a track-type (crawler-type) traveling device.

[0020] The drive unit 7 in FIG. 1 is configured to include an AC drive motor (electric motor) 21 arranged near the rear wheel 11 and driving the wheels or tracks of the travel unit 6, a fuel cell 22 arranged inside the bonnet 3 and supplying power to the drive motor 21, a controller 23 arranged inside the bonnet 3 and controlling the power supply from the fuel cell 22 to the drive motor 21, three hydrogen tanks 25 arranged in the upper part of the internal space S1 of the cabin 5 and supplying hydrogen gas for fuel to the fuel cell 22, a hydrogen gas detector (hydrogen gas detection unit) 52 arranged in the upper part of the internal space S1 of the cabin 5 and detecting hydrogen gas, and an exhaust door 53 provided on the ceiling wall 43 of the cabin 5, which opens when the hydrogen gas detector 52 detects hydrogen gas and communicates the internal space S1 of the cabin 5 with the outside. In this embodiment, an example in which three hydrogen tanks are arranged has been described for convenience, but the present invention is not limited to this, and may be configured to arrange, for example, one or more hydrogen tanks other than three. Here, the multiple hydrogen tanks may be connected in series or in parallel.

[0021] The output shaft of the drive motor 21 is indirectly or directly connected to the axle of the rear wheels 11 via a transmission mechanism, and is also switchably connected to the front wheels 12 via a 2WD / 4WD switching mechanism. The fuel cell 22 generates electricity by reacting hydrogen gas supplied from a hydrogen tank 25 with air (oxygen) taken in from the outside, and supplies this electricity to the drive motor 21. The controller 23 has an inverter function, converts the DC electricity generated by the fuel cell 22 into AC electricity, and controls the frequency to control the rotation of the drive motor 21. A battery 27 is also arranged inside the bonnet 3 to store surplus electricity of the power supplied from the fuel cell 22 to the drive motor 21.

[0022] The three-point link mechanism 9 includes a pair of left and right lower links 31 supported on the lower rear end of the vehicle body 2 so as to be rotatable in the vertical direction, a pair of left and right lift arms 32 supported on the upper rear end of the vehicle body 2 so as to be rotatable in the vertical direction and driven by a hydraulic device, a connecting link 33 connecting the rear ends of the lift arms 32 to the middle parts of the lower links 31 and rotating the lower links 31 by rotating the lift arms 32, and a bracket 34 for mounting an upper link. The upper link connected to the rear ends of the pair of left and right lower links 31 and the bracket 34 supports various working devices so as to be movable in the vertical direction. The PTO shaft 10 is connected to the input parts of various working devices via a drive shaft. The PTO shaft 10 is rotated by power transmitted from a drive motor 21. Here, the working equipment includes tilling equipment, fertilizer spreading equipment, pesticide spreading equipment, harvesting equipment, harvesting equipment, harvesting equipment, spreading equipment, grass, etc., grass collecting equipment, grass forming equipment (roll baler), etc.

[0023] Next, the hydrogen tank 25, hydrogen gas detector (hydrogen gas detection unit) 52, and exhaust door 53, which are disposed in the upper portion of the internal space S1 of the cabin 5 in FIG. 1, as well as their respective mounting structures, will be described in detail.

[0024] The cabin 5 in Fig. 1 is composed of four cabin frames (pillars) 41 rising from the four corners, transparent walls (not numbered) covering the front, right and rear sides, a transparent boarding and alighting door 42 covering the left side, and a ceiling wall 43. Here, a control device 44 including a handle and the like is disposed in front of the cockpit 4, and an air conditioner (air conditioner) for conditioning the internal space S1 of the cabin 5 is disposed under the cockpit 4. A conditioner unit 46 is disposed in the cabin 5. Also, below the cabin 5, there is disposed a boarding / alighting step 8 on which an operator places his / her feet when getting on and off the cabin 5. Here, the boarding / alighting step 8 is provided below each of the boarding / alighting doors 42 on the left and right sides.

[0025] The ceiling wall 43 has a double structure composed of an upper first wall 43a and a lower second wall 43b that face each other in the vertical direction, and three hydrogen tanks 25 are arranged in a ceiling space (guide passage) 45 sandwiched between the first wall 43a and the second wall 43b. Here, the ceiling space (guide passage) 45 is formed using the space between the first wall 43a and the second wall 43b. Furthermore, the three hydrogen tanks 25 are each formed in a cylindrical shape, extend in the width direction, and are arranged at equal intervals in the front-rear direction. Furthermore, each hydrogen tank 25 is supported by the first wall 43a and the second wall 43b via a vibration absorbing member 47 such as rubber. Here, a hydrogen gas detector (hydrogen gas detection unit) 52 is provided on the lower surface of the first wall 43a, and a sliding exhaust door 53 is provided in the front part of the first wall 43a. In addition, the exhaust door 53 is provided with an actuator (not shown) that is linked to the hydrogen gas detector 52, and when the hydrogen gas detector 52 detects a certain amount of hydrogen gas or more, the exhaust door 53 is automatically opened and the hydrogen gas that has leaked into the ceiling space 45 is released through the exhaust door 53.

[0026] FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. 1, and clarifies the arrangement of the hydrogen tank 25 and the structure of the outside air intake path E of the air conditioning unit 46.

[0027] 2, the air conditioner unit 46 has a cooling function, a heating function, and a blowing function, and is connected to an outside air introduction path E for introducing outside air. The outside air introduction path E is composed of a plurality of ducts 48a, 48b, 48c, 48d connected to extend upward from an inlet on the left side of the air conditioner unit 46 along the left side of the cabin 5, and a ceiling space 45 communicating with the upper end of the uppermost duct 48d, and uses the ceiling space 45 housing the hydrogen tank 25 as a guide path for the outside air. An outside air intake 51 opening downward to the outside is formed at the right end of the ceiling space 45. Here, the air conditioner unit 46 is configured to introduce outside air into the cabin 5. In detail, the outside air intake 51 of the air conditioner unit 46 is provided in the cabin 5, and a ceiling space (guide path) 45 is provided in which the outside air taken in from the outside air intake 51 passes through the outer periphery of the hydrogen tank 25. That is, the outside air introduction path E crosses the ceiling space (guide passage) 45 from right to left from the outside air intake 51, extends downward from the left end of the ceiling space (guide passage) 45 through multiple ducts 48d, 48c, 48b, and finally reaches the air conditioning unit 46 via the lowest duct 48a.

[0028] A hydrogen gas detector 52 is disposed near the nozzle 25 a of the hydrogen tank 25 and is attached to the underside of the first wall 43 a of the ceiling wall 43 .

[0029] 3 is a plan view (top view) of the cabin 5, in which the outside air intake 51 is located at the right front end of the ceiling wall 43, while the upper end of the uppermost duct 48d is located at the left rear end of the ceiling wall 43. In addition, the sliding exhaust door 53 is located near the nozzle 25a of the hydrogen tank 25.

[0030] 4 is a vertical cross-sectional view of hydrogen tank 25, which has a liner 60 with an internal space filled with hydrogen gas, and the outer surface of liner 60 is covered with a carbon fiber reinforced plastic (CFRP) layer 61. Here, liner 60 stores high-pressure gas, stores hydrogen gas by increasing the pressure or cooling, and releases hydrogen gas by decreasing the pressure or heating. Hydrogen tank 25 is a high-pressure hydrogen tank. With this configuration, it is possible to store a large amount of hydrogen gas and the hydrogen tank is lighter, making it easier to handle and enabling the vehicle weight to be lighter.

[0031] The operation and function of the tractor 1 equipped with the hydrogen tank 25 as configured above will be described below.

[0032] First, the basic operation of the drive device 7 that utilizes the fuel cell 22 mounted on the tractor 1, which is a work machine according to this embodiment, will be described. The fuel cell 22 generates electricity by reacting hydrogen gas supplied from a high-pressure hydrogen tank 25 with air (oxygen) taken in from the outside air. At this time, the only substance discharged is water; no harmful substances such as carbon dioxide are discharged.

[0033] The generated DC power is converted to AC power and frequency-controlled by the controller 23 and supplied to the drive motor 21, causing the output shaft of the drive motor 21 to rotate at a desired rotational speed.

[0034] The rotational power of the drive motor 21 is indirectly or directly transmitted to the axle of the rear wheels 11 via a transmission mechanism, causing the rear wheels 11 to rotate, for example, to travel in a two-wheel drive state. If necessary, the rotational power is also transmitted to the front wheels 12, for travel in a four-wheel drive state. Furthermore, the rotational power is also transmitted to the PTO shaft 10, for driving the working device.

[0035] Next, when air conditioning unit 46 is operated, outside air taken in through outside air intake 51 in ceiling wall 43 passes through outside air introduction path E and is introduced into air conditioning unit 46. In this introduction process, ceiling space 45 housing hydrogen tank 25 is used as a guide passage, so that hydrogen tank 25 is actively cooled by the outside air passing around hydrogen tank 25 within ceiling space 45. In other words, it is possible to suppress a rise in temperature of hydrogen tank 25.

[0036] Here, in the event that the tractor 1 rolls over, the hydrogen tank 25 is protected by the ceiling wall 43 of the cabin 5, so that damage to the hydrogen tank 25 can be avoided.

[0037] Furthermore, if hydrogen gas leaks into ceiling space 45, hydrogen gas detector 52 disposed near nozzle 25a of hydrogen tank 25 detects the leaked hydrogen gas and immediately opens exhaust door 53. Therefore, if hydrogen gas leaks into ceiling space 45, it becomes possible to immediately exhaust the leaked hydrogen gas via exhaust door 53.

[0038] The effects of this embodiment are summarized as follows.

[0039] Since the hydrogen tank 25 is positioned at the top of the interior space S1 of the cabin 5, it is easier to secure the placement space and it is possible to further suppress the temperature rise of the hydrogen tank 25 compared to a case in which the hydrogen tank 25 is housed inside the hood together with a heat-generating component such as a fuel cell.

[0040] Since the hydrogen tank 25 is disposed inside the cabin 5, the hydrogen tank 25 can be protected from external shocks and vibrations caused by the tractor 1 tipping over, etc.

[0041] The hydrogen tank 25 is lighter than conventional high-pressure hydrogen tanks because the outer surface of the liner 60 is covered with a carbon fiber reinforced resin layer 61. This makes it possible to store a large amount of hydrogen gas, and the lighter hydrogen tank 25 makes it easier to handle and allows the vehicle weight to be reduced.

[0042] Since the hydrogen gas detector 52 is disposed in the upper portion of the internal space S1 of the cabin 5, even if a hydrogen gas leak occurs, the hydrogen gas leak can be detected early and a countermeasure can be taken.

[0043] In addition, an exhaust door 53 linked to the hydrogen gas detector 52 is provided on the ceiling wall 43 (first wall 43a). Therefore, when leaking hydrogen gas is detected, the exhaust door 53 is automatically and quickly opened, making it possible to immediately exhaust the leaking hydrogen gas upward from the cabin 5.

[0044] Since an air conditioning unit 46 that adjusts the air inside the cabin 5 is provided, the temperature around the hydrogen tank 25 can be adjusted without the need to take the trouble of installing an additional cooling device for the high-pressure hydrogen tank. Furthermore, since the outside air taken in from the outside air intake 51 in the ceiling wall 43 passes around the hydrogen tank 25 in the ceiling space (guide passage 45), the outside air for the air conditioning unit 46 can be used efficiently to cool the hydrogen tank 25.

[0045] The ceiling wall 43 of the cabin 5 has a double structure consisting of an upper first wall 43a and a lower second wall 43b, and the ceiling space 45 between the first wall 43a and the second wall 43b is used as a guide passage for introducing outside air to the air conditioning unit 46. Therefore, since the existing structure is used without adding an additional guide passage for introducing outside air to the air conditioning unit 46, it is possible to reduce costs and maintain the compactness of the vehicle.

[0046] Since the hydrogen tank 25 is disposed in the ceiling space 45 between the first wall 43a and the second wall 43b, the function of protecting the high-pressure hydrogen tank 25 from external obstacles is improved.

[0047] [Second embodiment] In the above-described first embodiment, there is provided an exhaust door 53 that automatically opens when the hydrogen gas detector 52 detects a certain amount or more of hydrogen gas. In contrast, in the present embodiment, there is further provided a ventilation device 63 that ventilates the internal space S1 of the cabin 5.

[0048] Fig. 5 is a schematic side view of an agricultural tractor 1A according to a second embodiment of the present invention. The tractor 1A in Fig. 5 differs from the tractor 1 in Fig. 1 in that a ventilation device 63 is provided on the upper part of the right side wall of the cabin 5. The ventilation device 63 in Fig. 5 ventilates the internal space S1 of the cabin 5 at least while the hydrogen tank 25 supplies hydrogen gas to the fuel cell 22. This configuration makes it possible to prevent the temperature of the internal space S1 of the cabin 5 from increasing, and thus further prevents the hydrogen tank 25 from increasing in temperature.

[0049] Moreover, the ventilation device 63 in FIG. 5 includes a fan 63a and a motor 63b, and the motor 63b is supplied with power from the fuel cell 22 and is electrically connected to the controller 23. Here, the controller 23 controls the motor 63b to operate and ventilate the internal space S1 of the cabin 5 while hydrogen gas is being supplied from the hydrogen tank 25 to the fuel cell 22. Note that the motor 63b is configured to be supplied with power from the fuel cell 22, but may be configured to be supplied with power from the battery 27 arranged in the hood 3. The controller 23 is also electrically connected to the hydrogen gas detector 52, and when the hydrogen gas detector 52 detects a hydrogen gas leak, the controller 23 controls the motor 63b to increase its rotation speed, thereby increasing the ventilation output of the ventilation device 63. With this configuration, when hydrogen gas leaks from the hydrogen tank 25, it becomes possible to exhaust the leaked hydrogen gas in the cabin 5 to the outside of the cabin 5.

[0050] The operation of the tractor 1A according to the second embodiment configured as above is similar to that of the tractor 1 according to the first embodiment.

[0051] According to the tractor 1A of the above embodiment, compared to the tractor 1 of the first embodiment, the hydrogen tank 25 arranged inside the cabin 5 can be prevented from becoming too hot, and when the hydrogen gas detector 52 detects hydrogen gas, the output of the motor 63b of the ventilation device 63 is increased, so that when a hydrogen gas leak occurs, the leaked hydrogen gas inside the cabin 5 can be exhausted to the outside of the cabin 5.

[0052] [Third embodiment] Fig. 6 is a schematic side view of an agricultural tractor 1B according to a third embodiment of the present invention. The tractor 1B in Fig. 6 is different from the tractor 1 in Fig. 1 in that the ceiling space 45 in Fig. 1 is used as a guide passage for the outside air intake of the air conditioning unit 46, whereas the tractor 1B in Fig. 6 uses the ceiling space 45 as a cooling passage for the cooling air discharged from the air conditioning unit 46 into the cabin 5.

[0053] 6, an air conditioning unit 46 is provided below the cockpit 4 to generate cooling air and introduce the cooling air into the cabin 5. Here, the ceiling space 45 of the cabin 5 is used as a cooling passage for passing a part or all of the cooling air generated by the air conditioning unit 46 around the hydrogen tank 25. That is, the cabin 5 is provided with a duct 65b for introducing the cooling air or a part of it from a cooling air inlet 65a of the air conditioning unit 46 into the ceiling space (cooling passage) 45. With this configuration, the cooling air introduced from the air conditioning unit 46 passes around the outer periphery of the hydrogen tank 25, making it possible to further suppress the temperature rise of the hydrogen tank 25.

[0054] The operation of the tractor 1B according to the third embodiment configured as above is similar to that of the tractor 1 according to the first embodiment.

[0055] In the tractor 1B according to the above embodiment, compared to the tractor 1 according to the first embodiment, the air conditioning unit 46 for cooling the cabin 5 can also be used to cool the hydrogen tank 25, so the hydrogen tank 25 can be cooled without adding additional cooling equipment. This makes it possible to reduce the cost of adding additional cooling equipment and improve the cooling effect.

[0056] [Other embodiments] (1) FIG. 7 shows a modified example of the support mechanism for the hydrogen tank 25, and illustrates an example in which a cylindrical metal storage case 70 is used. A plurality of rubber vibration absorbing members 71 are provided at equal intervals around the circumference of the tank on the inner surface (mounting surface) 70a of the storage case 70. Cooling water W is stored inside the storage case 70, and the hydrogen tank 25 is stored inside the storage case 70 and elastically supported by three vibration absorbing members 71. Here, the storage case 70 for storing the hydrogen tank 25 is provided, and water for cooling the hydrogen tank 70 is stored in the storage case 70. With this configuration, the high-pressure hydrogen tank 25 can be actively and efficiently cooled, and the shock or vibration from the outside can be absorbed by the buffering effect of the water W. The hydrogen tank 25 may be configured to be installed on the mounting surface formed inside the storage case 70 via the vibration absorbing members 71.

[0057] Here, storage case 70 has an openable and closable lid 72, and the inside of storage case 70 can be kept sealed by closing lid 72 in a liquid-tight manner with lock clamp mechanism 73. Storage case 70 is disposed, for example, in ceiling space 45 of ceiling wall 43 in Fig. 1, or attached to the underside of a ceiling wall (not shown) that does not have a double structure.

[0058] According to the modified example of Figure 7, the high-pressure hydrogen tank 25 can be actively and efficiently cooled, and also, with respect to external shocks or vibrations, the shocks or vibrations can be better absorbed by the absorbing action of the vibration absorbing member 71 and the buffering by the water W.

[0059] (2) The working machine to which the present invention is applicable is not limited to agricultural tractors, but can be applied to construction machines such as large combine harvesters with cabins or backhoes with cabins. .

[0060] As described above, the work machine 1 according to the first aspect of the present invention is a work machine 1 comprising a vehicle body 2, a traveling device 6 supporting the vehicle body 2, a drive device 7 for driving the traveling device 6, and a cabin 5 for accommodating a cockpit 4, and the drive device 7 has a drive motor 21 for driving the traveling device 6, a fuel cell 22 for supplying power to the drive motor 21, a controller 23 for controlling the supply of power from the fuel cell 22 to the drive motor 21, and a hydrogen tank 25 for supplying hydrogen gas for fuel to the fuel cell 22, and the hydrogen tank 25 is arranged at the top of the internal space S1 of the cabin 5.

[0061] According to this configuration, the hydrogen tank 25 is disposed at the top of the interior space S1 of the cabin 5, which makes it easier to secure the space required for placement and also makes it possible to further suppress the rise in temperature of the hydrogen tank 25, compared to a case in which the hydrogen tank 25 is housed inside the bonnet 3 together with a heat-generating component such as the fuel cell 22.

[0062] In addition, the work machine 1 is further provided with a hydrogen gas detection unit 52 that detects hydrogen gas, and the hydrogen gas detection unit 52 is disposed in an upper portion of the internal space S1 of the cabin 5.

[0063] According to this configuration, since the hydrogen gas detection unit 52 is disposed at the upper part of the internal space S1 of the cabin 5, even if there is a hydrogen gas leak, the hydrogen gas leak can be detected early and a countermeasure can be taken.

[0064] In addition, the ceiling wall 43 of the cabin 5 is further provided with an exhaust door 53 that opens when the hydrogen gas detection unit 52 detects hydrogen gas and connects the internal space S1 of the cabin 5 to the outside.

[0065] According to this configuration, an exhaust door 53 linked to the hydrogen gas detection unit 52 is provided on the ceiling wall 43, so that when leaked hydrogen gas is detected, the exhaust door 53 is automatically and quickly opened, making it possible to immediately exhaust the hydrogen gas that has leaked upward from within the cabin 5.

[0066] The cabin 5 is further provided with a ventilation device 63 for ventilating the internal space S1 of the cabin 5, and the ventilation device 63 performs ventilation at least while the hydrogen tank 25 is supplying hydrogen gas to the fuel cell 22.

[0067] According to this configuration, the internal space S1 of the cabin 5 is ventilated at least while the hydrogen tank 25 is supplying hydrogen gas to the fuel cell 22, thereby preventing the temperature of the internal space S1 of the cabin 5 from becoming too high, and ultimately preventing the hydrogen tank 25 from becoming too high.

[0068] Moreover, the work machine 1 further includes a hydrogen gas detector 52 that detects hydrogen gas, and the ventilation device 63 increases the ventilation output when the hydrogen gas detector 52 detects hydrogen gas.

[0069] According to this configuration, when hydrogen gas leaks from the hydrogen tank 25, the leaked hydrogen gas inside the cabin 5 can be discharged to the outside of the cabin 5.

[0070] In addition, the work machine 1 is further equipped with an air conditioning unit 46 that generates cooling air and introduces the cooling air into the cabin 5, and the cabin 5 is provided with a cooling passage through which the cooling air introduced from the air conditioning unit 46 passes around the outer periphery of the hydrogen tank 25.

[0071] According to this configuration, the cooling air introduced from the air conditioning unit 46 is blown out of the hydrogen tank 25. Since the hydrogen tank 25 passes through the circumference, the temperature rise in the hydrogen tank 25 can be further suppressed.

[0072] In addition, the work machine 1 is further equipped with an air conditioning unit 46 that introduces outside air into the cabin 5, an outside air intake 51 of the air conditioning unit 46 is provided in the cabin 5, and a guide passage 45 is provided through which the outside air taken in from the outside air intake 51 passes around the outer periphery of the hydrogen tank 25.

[0073] According to this configuration, since an air conditioning unit 46 that adjusts the air inside the cabin 5 is provided, the temperature around the hydrogen tank 25 can be adjusted without the need to add a cooling device for the high-pressure hydrogen tank 25. Furthermore, since the outside air taken in from the outside air intake 51 in the ceiling wall 43 passes around the hydrogen tank 25 in the ceiling space (guide passage 45), the outside air for the air conditioning unit 46 can be used efficiently to cool the hydrogen tank 25.

[0074] In addition, the ceiling wall 43 of the cabin 5 has a double structure consisting of an upper first wall 43a and a lower second wall 43b, and the guide passage 45 is formed using the space between the first wall 43a and the second wall 43b.

[0075] According to this configuration, the ceiling wall 43 of the cabin 5 has a double structure composed of an upper first wall 43a and a lower second wall 43b, and the ceiling space between the first wall 43a and the second wall 43b is used as a guide passage 45 for introducing outside air to the air conditioning unit 46. Therefore, since the existing structure is used without adding an additional guide passage 45 for introducing outside air to the air conditioning unit 46, it is possible to reduce costs and maintain the compactness of the vehicle.

[0076] In addition, the ceiling wall 43 of the cabin 5 has a double structure consisting of an upper first wall 43a and a lower second wall 43b, and the hydrogen tank 25 is arranged in the space between the first wall 43a and the second wall 43b.

[0077] According to this configuration, the hydrogen tank 25 is disposed in the ceiling space between the first wall 43a and the second wall 43b, thereby improving the function of protecting the high-pressure hydrogen tank 25 from external obstacles.

[0078] Moreover, the work machine 1 further includes a storage case 70 for storing the hydrogen tank 25, and water for cooling the hydrogen tank 25 is stored in the storage case 70.

[0079] According to this configuration, the high-pressure hydrogen tank 25 can be actively and efficiently cooled, and also, with respect to external shocks or vibrations, the shocks or vibrations can be better absorbed by the buffering effect of the water.

[0080] Moreover, the work machine 1 further includes a storage case 70 for storing the hydrogen tank 25, and the hydrogen tank 25 is placed on a mounting surface formed inside the storage case 70 via a vibration absorbing member 71.

[0081] According to this configuration, the absorbing effect of the vibration absorbing member 71 makes it possible to absorb shocks or vibrations more effectively.

[0082] Moreover, the hydrogen tank 25 has a liner having an internal space S1 filled with hydrogen gas, and the outer surface of the liner is covered with a carbon fiber reinforced resin layer 61.

[0083] According to this configuration, it is possible to store a large amount of hydrogen gas and the hydrogen tank 25 is lighter in weight, making it easier to handle and enabling the vehicle weight to be reduced.

[0084] Although the present invention has been described above, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0085] 1 Tractor 2. Body 3. Bonnet 4. Cockpit 5 Cabin 6 Running gear 11 Rear wheel 12 Front wheel 21 Drive motor 22 Fuel Cell 23 Controller 25 Hydrogen Tank 41 Cabin Frame 43 Ceiling Wall 43a First Wall 43b 2nd wall 44 Controls 45 Ceiling space (used as a guide passage or cooling passage) 46 Air conditioner unit 51 Fresh air intake 52 Hydrogen gas detector (hydrogen gas detector) 53 Exhaust door 63 Ventilation system 70 Storage Case 71 Vibration absorbing material E. Outside air intake route

Claims

1. The car body and A drive motor; A PTO shaft that rotates by power transmission from the drive motor; a fuel cell disposed in a front portion of the vehicle body and supplying power to the drive motor; A cockpit arranged behind the fuel cell; and a plurality of hydrogen tanks disposed above the cockpit; A tractor in which the multiple hydrogen tanks are lined up from the front to the rear of the cockpit.

2. A control device is provided in front of the cockpit, 2. The tractor of claim 1, wherein at least one hydrogen tank of the plurality of hydrogen tanks is located above the steering device.

3. 3. The tractor according to claim 2, wherein the fuel cell is disposed forward of the operator's seat and the operation device.

4. The tractor according to any one of claims 1 to 3, further comprising a ceiling wall located between the plurality of hydrogen tanks and the operator's seat.

5. Each of the plurality of hydrogen tanks has a mouthpiece, 5. The tractor according to claim 1, wherein each of the plurality of hydrogen tanks is arranged with the mouthpiece facing in a direction perpendicular to the front-rear direction.

6. 6. The tractor according to claim 1, wherein each of the plurality of hydrogen tanks is formed in a cylindrical shape and extends in a direction perpendicular to the front-rear direction.

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