Tractor

Abstract

The present invention provides a tractor with excellent maneuverability.　A tractor (1) comprises: a vehicle body frame (2A); a travel device (3) that includes front wheels (3F) and supports the vehicle body frame in a travelable manner; a driver's seat (4A) provided on the vehicle body frame; a support device (S) provided on the vehicle body frame; a power supply device (7) supported by the support device; and a monitoring assistance device (20) which is provided on the support device and which enables a driver to visually recognize the surroundings of a forward-travel road surface of the vehicle, including the front wheels, from the driver's seat.

Description

Tractor

[0001] The present invention relates to a tractor.

[0002] The tractor disclosed in Patent Document 1 includes a tank for storing hydrogen gas, a fuel cell, and an electric motor. The motor is driven by the electric power generated by the fuel cell to run. The fuel cell is housed inside the bonnet provided in front of the driver's seat. For this type of tractor, in order to maintain a stable output over a long period of time, it is required to increase the size of the fuel cell.

[0003] Japanese Patent Application Laid-Open Publication "JP-A-2024-095105"

[0004] However, for this type of tractor, as the size of the fuel cell increases, the bonnet also becomes larger, so it is impossible to sufficiently visually recognize the surrounding of the traveling road surface around the front wheels or in front of the front wheels from the driver's seat, which may hinder proper operation. <00FFFF0> The present invention has been made in view of the above problems, and an object thereof is to provide a tractor excellent in maneuverability that can be appropriately operated by a driver.

[0006] The present invention employs the following technical means to achieve the above object.

[0007] A tractor according to one aspect of the present invention includes a vehicle body frame, a traveling device including front wheels and capable of supporting the vehicle body frame to travel, a driver's seat provided on the vehicle body frame, a support device provided on the vehicle body frame, a power supply device supported by the support device, and a monitoring assistance device provided on the support device and enabling a driver to visually recognize the surrounding of the forward traveling road surface of the vehicle including the front wheels from the driver's seat. <000001FFFF6> According to the above tractor, since the surrounding of the forward traveling road surface of the vehicle including the front wheels can be visually recognized from the driver's seat, a tractor excellent in maneuverability can be provided.

[0009] This is a front perspective view of the tractor of the present invention. This is a side view of the tractor of the present invention. This is an upper view of the tractor of the present invention. This is a front view of the tractor of the present invention. This is a rear view of the tractor of the present invention. This is a rear perspective view of a part of the tractor of the present invention that has been disassembled. This is an upper view of the body frame. This is a block diagram showing the basic configuration of the tractor of the present invention. This is a lower perspective view of the cover support frame and tank case. This is a rear perspective view of the tank stay, tank cover, and cover support frame. This is a rear view of the area near the handle. This is a front perspective view of the tractor of the first modified example. This is a side view of the tractor of the first modified example. This is a front view of the tractor of the first modified example. This is a front perspective view of the tractor of the second modified example. This is a side view of the tractor of the second modified example. This is a front view of the tractor of the second modified example. This is a front perspective view of the tractor of the third modified example. This is a side view of the tractor of the third modified example. This is a front view of the tractor of the third modified example. This is a side view of the tractor of the fourth modified example. This is a rear perspective view of the tank stay of the fourth modified example. This is a front view of the tractor of the fifth modified example. This is a side view of the tractor of the sixth modified example.

[0010] Embodiments of the present invention will be described with reference to the drawings. Figures 1 to 5 show a tractor 1 according to one embodiment of the present invention. The tractor 1 of this embodiment is used by connecting it with implements such as tillers and balers, mainly according to the purpose and use of agricultural work. The tractor 1 of this embodiment is a type of FCV (Fuel Cell Vehicle) that is driven using electricity generated by a fuel cell.

[0011] In the following explanation, the longitudinal direction of the vehicle body 2, which is the direction of straight-line travel of the tractor 1 (indicated by arrows X1 and X2 in Figures 1 to 3), will be referred to as the front-rear direction, the width direction of the vehicle body 2 (indicated by arrows Y1 and Y2 in Figures 1, 3 to 5), will be referred to as the left-right direction, and the height direction of the vehicle body 2 (indicated by arrows Z1 and Z2 in Figures 1, 2, 4, and 5), will be referred to as the up-down direction.

[0012] As shown in Figures 5 to 7, the tractor 1 of this embodiment is equipped with a coupling device 1U and a PTO shaft (power take-off shaft) 2U. Both the coupling device 1U and the PTO shaft 2U are located at the rear of the vehicle body 2. When the above-mentioned work device is coupled to the tractor 1 for use, the coupling device 1U engages with and holds the work device. The PTO shaft 2U is connected to the passive shaft of the work device via a universal joint.

[0013] The coupling device 1U is a device for connecting the work equipment to the vehicle body 2. The coupling device 1U is located at the rear of the power transmission device 2B. In this embodiment, the coupling device 1U is a three-point linkage mechanism for connecting and raising / lowering the work equipment. The coupling device 1U has a hydraulic cylinder for raising and lowering the work equipment.

[0014] As shown in Figures 1 to 3, the tractor 1 comprises a body 2, a running gear 3, a driver's seat 4A, a steering wheel 4B, and a bonnet 5. The tractor 1 may also have a cabin 6. As shown in Figures 1 and 2, the tractor 1 comprises a power supply device 7 and an electric motor 8. The power supply device 7 includes a tank 9, a fuel cell stack (fuel cell) 10, and a battery unit 11. In other words, the power supply device 7 is a device for supplying power to the electric motor 8, etc. As shown in Figures 1 to 6, the tractor 1 comprises a tank stay 12 and a tank cover 13.

[0015] As shown in Figures 2 and 8, the tractor 1 is equipped with a radiator system 14. As shown in Figure 8, the tractor 1 is equipped with an inverter 41 and a DC / DC converter 42. The radiator system 14 includes a first radiator system 14A and a second radiator system 14B. The first radiator system 14A has a first heat exchanger 43 and a first fan 45. The second radiator system 14B has a second heat exchanger 44 and a second fan 46. Details of the radiator system 14 will be described later.

[0016] As shown in Figures 1 and 2, the vehicle body 2 includes a vehicle frame 2A and a power transmission device 2B. The vehicle frame 2A is a long structure in the front-to-rear direction, made of metal frame material or the like. The bonnet 5 is supported on the upper part of the vehicle frame 2A. Details of the power transmission device 2B will be described later.

[0017] The vehicle body 2 has a stay mounting portion 2C. The vehicle body 2 has a plurality of stay mounting portions 2C. The tank stay 12 is connected and supported to the stay mounting portion 2C. The tank 9 is supported on the upper part of the tank stay 12. That is, the tank 9 is supported on the upper part of the vehicle body 2 via the tank stay 12, which acts as a support device S.

[0018] As shown in Figures 1, 2, and 6, the power transmission device 2B is connected to the rear of the vehicle frame 2A. That is, the rear of the vehicle body 2 is composed of the power transmission device 2B. The PTO shaft 2U is connected to the rear of the power transmission device 2B. The power transmission device 2B has a clutch device, a transmission device, a differential device, etc., and reduces or increases the speed of the electric motor 8 and outputs it to the running gear 3 and the PTO shaft 2U.

[0019] Furthermore, the power transmission device 2B is connected to a hydraulic pump, and the electric motor 8 also outputs power to the hydraulic pump. The hydraulic cylinders that steer the traveling device 3 and the hydraulic cylinders that raise and lower the coupling device 1U are driven by the hydraulic fluid (pressurized oil) discharged from the hydraulic pump.

[0020] As shown in Figures 1 to 6, the running gear 3 supports the vehicle body 2 so that it can move. The running gear 3 of this embodiment includes front wheels 3F that support the front of the vehicle body 2 and rear wheels 3R ​​that support the rear of the vehicle body 2. The front wheels 3F are located at the bottom of the vehicle body frame 2A. The rear wheels 3R ​​are located at the bottom of the power transmission device 2B.

[0021] Furthermore, the running gear 3 is not limited to wheels. For example, the running gear 3 may be a crawler. Also, of the running gear 3 that supports the front and rear of the vehicle body 2, one may be wheels and the other may be a crawler.

[0022] The running gear 3 is driven by the power of an electric motor 8 transmitted via a power transmission device 2B. In this embodiment, the power transmission device 2B is configured to be switchable between a two-wheel drive state in which the power of the electric motor 8 is transmitted only to the rear wheels 3R ​​of the running gear 3, and a four-wheel drive state in which the power of the electric motor 8 is transmitted to both the front wheels 3F and the rear wheels 3R.

[0023] In other words, the tractor 1 of this embodiment is a four-wheel drive vehicle capable of running with both the front wheels 3F and the rear wheels 3R ​​as drive wheels, and is configured to be able to be arbitrarily switched to a two-wheel drive vehicle state in which only the rear wheels 3R ​​are driven wheels, according to the driver's drive switching operation. Note that the tractor 1 may be a two-wheel drive vehicle that runs with only the front wheels 3F as drive wheels, or a two-wheel drive vehicle that runs with only the rear wheels 3R ​​as drive wheels.

[0024] As shown in Figures 1 to 3, the driver's seat 4A, steering wheel 4B, bonnet 5, and cabin 6 are all located on the upper part of the vehicle body 2. The driver's seat 4A is located on top of the power transmission unit 2B. The steering wheel 4B is located on top of the power transmission unit 2B. The bonnet 5 is a cover that covers the front of the vehicle body 2 and is provided on top of the vehicle frame 2A. The cabin 6 is a protective device that protects the driver's seat 4A and is erected on top of the power transmission unit 2B. Note that the tractor 1 may be equipped with a canopy instead of the cabin 6 as a protective device for the driver's seat 4A.

[0025] As shown in Figure 3, the driver's seat 4A is located approximately in the center between the left and right sides inside the cabin 6. In this embodiment, the driver's seat 4A is located on the X-axis centerline CL1 that passes through the center between the left and right sides of the tractor 1 when viewed from above. The steering wheel 4B is a steering device that steers either one or both of the front wheels 3F and the rear wheels 3R ​​in response to rotational operation, and is located in front of the driver's seat 4A inside the cabin 6 at a predetermined distance.

[0026] As shown in Figures 1 to 4, the bonnet 5 is located in front of the cabin 6. That is, the bonnet 5 is located in front of the driver's seat 4A. The fuel cell stack 10 is supported inside the bonnet 5. That is, the fuel cell stack 10 is supported on the upper part of the vehicle body 2 inside the bonnet 5, which acts as a support device S. The second radiator unit 14B is also housed inside the bonnet 5, positioned front to back with the fuel cell stack 10.

[0027] Furthermore, the fuel cell stack 10 occupies a relatively large space inside the bonnet 5. In addition, several other pieces of equipment besides the fuel cell stack 10 are housed inside the bonnet 5. As a result, the bonnet 5 is formed in a relatively large box shape, which obstructs the driver's view of the area around the front wheels 3F and the road surface the vehicle is traveling on from the driver's seat 4A. Therefore, in this embodiment, the tractor 1 is equipped with a monitoring assistance device 20 so that the driver can properly view the area around the vehicle's road surface, including the front wheels 3F, from the driver's seat 4A. Details of the monitoring assistance device 20 will be described later.

[0028] As shown in Figures 1 and 2, the cabin 6 is a box-shaped structure that surrounds the driver's seat 4A from the front, rear, left, right, and above, and includes pillars 6P, a roof 6T, a front panel 6F, side panels 6S, and a rear panel 6R. The cabin 6 has side mirrors 21. As shown in Figures 3 and 4, the side mirrors 21 include a left side mirror 21L and a right side mirror 21R. As shown in Figures 1 to 4, the cabin 6 may also have combination lamps 22.

[0029] As shown in Figure 1, the pillar 6P is erected around the driver's seat 4A in the power transmission unit 2B. The pillar 6P includes the left front pillar 31 and the right front pillar 32. As shown in Figure 5, the pillar 6P includes the left side pillar 33 and the right side pillar 34.

[0030] As shown in Figure 1, the left front pillar 31 is erected to the left front of the driver's seat 4A. As shown in Figure 4, the right front pillar 32 is erected to the right front of the driver's seat 4A. The left side pillar 33 is erected to the left rear of the driver's seat 4A. As shown in Figure 5, the right side pillar 34 is erected to the right rear of the driver's seat 4A. As shown in Figures 1, 2, 4, and 5, the roof 6T is supported by the upper ends of these four pillars 6P.

[0031] As stated above, the cabin 6 of this embodiment has four pillars 6P, but the number of pillars 6P is not limited to four. For example, the cabin 6 may have five pillars 6P (in addition to the four pillars 6P mentioned above, a left center pillar or a right center pillar), or it may have six pillars 6P (in addition to the four pillars 6P mentioned above, a left center pillar and a right center pillar).

[0032] As shown in Figure 4, the front panel 6F is positioned in front of the driver's seat 4A and constitutes the front part of the cabin 6. The front panel 6F has a front window 35. The front window 35 is made of a transparent material such as glass and ensures a clear view of the area in front of the vehicle from the driver's seat 4A.

[0033] As shown in Figure 5, the rear panel 6R is positioned behind the driver's seat 4A and constitutes the rear surface of the cabin 6. The rear panel 6R has a rear window 36. The rear window 36 is made of a transparent material such as glass and ensures visibility to the rear of the vehicle from the driver's seat 4A.

[0034] As shown in Figure 2, the side panels 6S are positioned to the left and right of the driver's seat 4A, respectively, and constitute the left and right sides of the cabin 6. The right side of the cabin 6 is configured symmetrically with the left side of the cabin 6. Therefore, the configuration of the right side of the cabin 6 can be understood based on the left-side view of the tractor 1 shown in Figure 2.

[0035] The side panel 6S has a side window 37. The side window 37 is made of a transparent material such as glass and ensures a view of the side of the vehicle from the driver's seat 4A. In this embodiment, both the left and right side panels 6S are connected to the side pillars 33 and 34 on the same side by hinges and serve as boarding doors for the driver to enter and exit the driver's seat 4A. Note that only one of the side panels 6S may serve as a boarding door.

[0036] The left side mirror 21L is connected and supported to the upper part of the left front pillar 31 and is located to the left of the side window 37. In other words, the left side mirror 21L is located on the left front of the cabin 6. The right side mirror 21R is connected and supported to the upper part of the right front pillar 32 and is located to the right of the side window 37. In other words, the right front pillar 32 is located on the right front of the cabin 6.

[0037] The combination lamp 22 is a front combination lamp that integrates a side marker light and a turn signal light. The combination lamp 22 is positioned below the left side mirror 21L on the left front pillar 31, and below the right side mirror 21R on the right front pillar 32. In other words, the combination lamp 22 is provided on the left front and right front of the cabin 6. The height of these combination lamps 22 is set, for example, in accordance with vehicle safety standards.

[0038] As shown in Figures 1 and 2, the electric motor 8 is a drive device that drives the traction unit 3. The electric motor 8 is driven by power supplied from the fuel cell stack 10 or the battery unit 11. For example, the electric motor 8 is a three-phase AC synchronous motor with embedded permanent magnets. However, the electric motor 8 is not limited to a three-phase AC synchronous motor. For example, the electric motor 8 may be a synchronous motor in which coils are wound around a rotor and laminated steel plates are fitted to it. The electric motor 8 is not limited to an AC motor, but may also be a DC motor.

[0039] The electric motor 8 is connected to the power transmission device 2B and outputs power to the running gear 3 via the power transmission device 2B. The electric motor 8 is located below and rear of the fuel cell stack 10. In this embodiment, the electric motor 8 is incorporated into the rear of the vehicle body frame 2A. The electric motor 8 is located below the hood 5.

[0040] In this embodiment, one electric motor 8 is mounted on the vehicle body 2, and the power of the electric motor 8 is distributed and output to the front wheels 3F and rear wheels 3R ​​by the power transmission device 2B. Alternatively, two electric motors 8 may be mounted on the front and rear of the vehicle body 2, and the power of each electric motor 8 may be independently output to the front wheels 3F and rear wheels 3R, respectively. Or, the electric motors 8 may be independently provided on all four wheels, the left and right front wheels 3F and rear wheels 3R, and the power of the electric motor 8 may be individually output to the corresponding front wheels 3F and rear wheels 3R.

[0041] Tank 9 stores gas for power generation. In this embodiment, tank 9 stores hydrogen gas. Tank 9 is a substantially cylindrical container and can store gas under high pressure. Tank 9 is formed of, for example, a rigid synthetic resin reinforced with carbon fiber or glass fiber.

[0042] As shown in Figures 2, 5, and 8, the tractor 1 is equipped with a gas filling port (receptacle) 1G and a valve device V1. The tank 9 connects an external gas supply unit installed at a gas station or the like to the gas filling port 1G, and stores gas by filling it through the valve device V1 from the gas filling port 1G. In addition, the tank 9 may be configured to be replaceable with another tank 9 that is pre-filled with gas when the amount of gas stored becomes low, rather than replenishing it with hydrogen gas from the gas filling port 1G as described above.

[0043] The valve device V1 consists of an on-off valve, a pressure reducing valve, a check valve, etc., and introduces the gas injected into the gas filling port 1G into the tank 9. The valve device V1 adjusts the gas in the tank 9 to a predetermined flow rate and then leads it to the fuel cell stack 10.

[0044] As shown in FIGS. 1, 4 to 6, the tank 9 is provided above the cabin 6. As shown in FIG. 9, the tank 9 is housed in a substantially rectangular box-shaped tank case 16 to form one tank unit. The tractor 1 of the present embodiment includes three tanks 9. These three tanks 9 are provided side by side left and right in a posture with the longitudinal direction as the front-rear direction inside the tank case 16.

[0045] Note that only one tank 9 may be mounted on the vehicle body 2, or two tanks 9 may be mounted. Alternatively, four or more tanks 9 may be mounted on the vehicle body 2. For example, four or more tanks 9 may be provided side by side left and right inside the tank case 16, or four or more tanks 9 may be provided in a plurality of rows side by side left and right and arranged in a plurality of columns up and down inside the tank case 16.

[0046] The fuel cell stack 10 generates electricity using the gas supplied from the tank 9 and supplies electric power to the electric motor 8. The fuel cell stack 10 is configured by arranging a plurality of single cells each having two types of electrodes, a positive electrode and a negative electrode, in a stacked state inside a casing, and by aggregating the electric power generated by each single cell, generates the electric power of the voltage and current required for driving the electric motor 8.

[0047] As shown in FIG. 8, the fuel cell stack 10 is connected to the inverter 41 and the battery unit 11 via a boost circuit BC. The boost circuit BC boosts the electric power generated by the fuel cell stack 10. That is, the fuel cell stack 10 supplies the electric power boosted by the boost circuit BC to the inverter 41 and the battery unit 11. The inverter 41 is connected to the electric motor 8, converts the DC power input from the boost circuit BC into three-phase AC power, and outputs it to the electric motor 8. Thus, the fuel cell stack 10 drives the electric motor 8 with the electric power boosted by the boost circuit BC.

[0048] The fuel cell stack 10 is connected to a low-voltage device that operates at a voltage lower than that of the electric motor 8 via a step-down circuit. The step-down circuit is a DC / DC converter 42. In the present embodiment, the low-voltage devices include the first fan 45 of the first radiator device 14A, the second fan 46 of the second radiator device 14B, and the battery unit 11. The DC / DC converter 42 converts the voltage of the DC power input from the fuel cell stack 10 to a lower voltage and outputs it to each of the above low-voltage devices. Thus, the fuel cell stack 10 supplies the power stepped down by the DC / DC converter 42 to each low-voltage device.

[0049] The battery unit 11 stores the power supplied from the fuel cell stack 10 and appropriately outputs the stored power to the inverter 41 and the like. The battery unit 11 is a charge-discharge type secondary battery such as a lithium-ion battery or a lead-acid battery. As shown in FIGS. 2 and 7, the battery unit 11 is disposed between the front wheel 3F and the rear wheel 3R on the right side portion of the vehicle body 2.

[0050] As shown in FIGS. 1 to 3, the tank stay 12 is a support frame that supports the tank 9. The tank stay 12 is supported on the upper part of the vehicle body 2. As shown in FIG. 2, the tank stay 12 may support electrical components such as the second radiator device 14B in addition to the tank 9.

[0051] As shown in FIGS. 6 and 10, the tank stay 12 supports a tank case 16 that houses the tank 9 via a cover support frame 15. Thus, the tank 9 is supported by the tank stay 12 via the tank case 16 and the cover support frame 15.

[0052] The tank stay 12 has a function of stably supporting the tank 9 with respect to the vehicle body 2 and a function of absorbing the vibration of the vehicle body 2 during traveling or working and mitigating the impact on the tank 9. The tank stay 12 has a rigidity capable of stably supporting the heavy tank 9.

[0053] As shown in Figure 10, the tank stay 12 has a base frame 51, a plurality of support legs 52, and a radiator mounting portion 53. The base frame 51 is formed in a rectangular ring shape. As shown in Figures 3 and 6, the base frame 51 is positioned above the roof 6T.

[0054] The base frame 51 has a front frame portion 51F, a rear frame portion 51R, and a side frame portion 51S. As shown in Figure 3, the front frame portion 51F extends in the left-right direction forward of the front end of the roof 6T. The rear frame portion 51R extends in the left-right direction behind the rear end of the roof 6T.

[0055] The side frame sections 51S extend in the front-rear direction above the left and right side ends of the roof 6T. That is, two side frame sections 51S are arranged side by side above the roof 6T, spaced apart from each other. The side frame sections 51S connect the left and right ends of the front frame section 51F and the rear frame section 51R. The tank case 16 is attached to the left and right side frame sections 51S.

[0056] The support legs 52 are provided at the lower part of the base frame 51 and are connected to the stay mounting portion 2C of the vehicle body 2. That is, the support legs 52 support the base frame 51 at the stay mounting portion 2C of the vehicle body 2. As shown in Figure 10, the support legs 52 include a front support leg 52F, a central support leg 52C, and a rear support leg 52R.

[0057] In this embodiment, the central support leg 52C and the rear support leg 52R extend downward from the left and right sides of the base frame 51. The front support leg 52F extends toward the front of the vehicle body 2 from a position near the lower end of the middle section between the upper and lower parts of the central support leg 52C. That is, the front support leg 52F extends from the front of the vehicle body frame 2A, passing along the side of the bonnet 5, to a position below the central support leg 52C.

[0058] The front support legs 52F, the central support legs 52C, and the rear support legs 52R are each provided in pairs on the lower part of the base frame 51, spaced apart on the left and right, and are connected and supported at their lower ends to the stay mounting portion 2C of the vehicle body 2. Thus, in this embodiment, the tank stay 12 has six support legs 52.

[0059] Furthermore, the number of support legs 52 is not limited to six, as long as the tank 9 can be stably supported. For example, the tank stay 12 may be configured to support the tank 9 with four support legs 52 (front support leg 52F and rear support leg 52R, or central support leg 52C and rear support leg 52R), or with three or fewer support legs 52, or with seven or more support legs 52. Alternatively, the tank stay 12 may not have support legs 52, and the base frame 51 may be connected to the upper part of the roof 6T, that is, the cabin 6 may support the tank 9.

[0060] The front support legs 52F are located in the front and lower part of the base frame 51. The front support legs 52F are positioned on either side of the bonnet 5. As shown in Figure 3, the front support legs 52F extend forward of the front panel 6F (front window 35) of the cabin 6 and are connected to the stay mounting portion 2C of the vehicle body 2. That is, as shown in Figure 2, the front support legs 52F in this embodiment extend from the front of the vehicle body frame 2A, through the side of the bonnet 5, towards the driver's seat 4A.

[0061] The central support legs 52C are located at the front lower part of the base frame 51. As shown in Figure 3, the central support legs 52C are positioned on either side of the bonnet 5, flanking the bonnet 5. That is, the central support legs 52C are erected in front of the front panel 6F (front window 35). The central support legs 52C extend downward from the front end of the side frame portion 51S of the base frame 51, pass along the side of the bonnet 5, and are connected to the central stay mounting portion 24C of the vehicle body 2.

[0062] As shown in Figure 7, the stay mounting section 2C includes a front stay mounting section 24F, a central stay mounting section 24C, and a rear stay mounting section 24R. The front stay mounting section 24F, the central stay mounting section 24C, and the rear stay mounting section 24R are provided on the left and right sides of the vehicle body 2, respectively. In this way, the tank stay 12 is connected and supported by the stay mounting sections 2C provided at three locations on each side of the vehicle body 2.

[0063] The front stay mounting portion 24F is located at the front of the vehicle body 2. The front stay mounting portion 24F is located on the front side of the vehicle body frame 2A. The front stay mounting portion 24F is positioned in front of the front wheel 3F. The central stay mounting portion 24C is located in the middle of the vehicle body 2 in the longitudinal direction. The central stay mounting portion 24C is located on the rear side of the vehicle body frame 2A. The central stay mounting portion 24C is positioned behind the front wheel 3F. The rear stay mounting portion 24R is located at the rear of the vehicle body 2. The rear stay mounting portion 24R is located on the axle case of the rear wheel 3R (running gear 3) in the power transmission device 2B.

[0064] As shown in Figures 1 and 2, the front support leg 52F is connected at its front end to the front stay mounting portion 24F and at its rear end to a position near the lower end of the central support leg 52C. As shown in Figure 2, the central support leg 52C is connected at its lower end to the central stay mounting portion 24C and at its upper end to the base frame 51.

[0065] As shown in Figures 1, 2, 4, and 5, the tank cover 13 is a cover that covers the tank 9. As shown in Figure 2, the tank cover 13 covers not only the tank 9 but also the second radiator device 14B which is located on top of the tank stay 12.

[0066] As shown in Figures 6 and 10, the tank cover 13 is supported on the tank stay 12 via a cover support frame 15. The cover support frame 15 is fixed along the inner surface of the tank cover 13 and serves as a base member that reinforces the tank cover 13.

[0067] As shown in Figures 1, 2, 4, and 5, the tank cover 13 is a roughly rectangular box-shaped body that is long in the front-to-back direction, and has a front cover 13F, a rear cover 13R, side covers 13S, an upper cover 13T, and a lower cover 13U. The front cover 13F constitutes the front part of the tank cover 13. The rear cover 13R constitutes the rear part of the tank cover 13. The side covers 13S constitute the left and right side parts of the tank cover 13. The upper cover 13T constitutes the top part of the tank cover 13. The lower cover 13U constitutes the bottom part of the tank cover 13.

[0068] As shown in Figures 1 to 3, the tank cover 13 extends above the roof 6T from behind the rear end of the roof 6T to in front of the front end of the roof 6T. That is, the tank cover 13 is positioned on top of the tank stay 12 with its front portion protruding forward of the front end of the roof 6T.

[0069] The radiator unit 14 is a cooler that cools the coolant (refrigerant) circulated to equipment such as the electric motor 8, fuel cell stack 10, inverter 41, and DC / DC converter 42 by heat exchange with the outside air. As shown in Figure 2, the first radiator unit 14A is installed on the upper part of the vehicle frame 2A. The first radiator unit 14A is housed inside the bonnet 5. The second radiator unit 14B is attached to the radiator mounting portion 53 of the tank stay 12. The second radiator unit 14B is housed inside the tank cover 13.

[0070] As shown in Figure 8, the first radiator device 14A is connected to the electric motor 8, inverter 41, DC / DC converter 42, and boost circuit BC via a first coolant flow path H1, and the coolant circulating in the first coolant flow path H1 is cooled by heat exchange with the outside air. As a result, the electric motor 8, inverter 41, DC / DC converter 42, and boost circuit BC are maintained at a predetermined temperature or below.

[0071] The first heat exchange section 43 of the first radiator device 14A is a gas-liquid heat exchanger composed of a plurality of heat transfer fins and heat transfer tubes, and is connected to the first coolant flow path H1. The first fan 45 circulates air over the surface of the first heat exchange section 43, promoting heat exchange between the air and the coolant flowing inside the first heat exchange section 43. The first radiator device 14A may have only one first fan 45, or it may have two or more first fans 45.

[0072] The second radiator device 14B is connected to the fuel cell stack 10 via a second coolant flow path H2, and cools the coolant circulating in the second coolant flow path H2 by heat exchange with the outside air. As a result, the internal electrodes of the fuel cell stack 10 are maintained at a predetermined temperature or below. Consequently, the fuel cell stack 10 maintains a high power generation efficiency.

[0073] The second heat exchange section 44 of the second radiator device 14B is a gas-liquid heat exchanger composed of a plurality of heat transfer fins and heat transfer tubes, and is connected to the second coolant flow path H2. The second fan 46 circulates air over the surface of the second heat exchange section 44, promoting heat exchange between the air and the coolant flowing inside the second heat exchange section 44. The second radiator device 14B may have only one second fan 46, or it may have two or more second fans 46.

[0074] As shown in Figures 1, 2, and 4, the tractor 1 is equipped with a monitoring assistance device 20. The monitoring assistance device 20 in this embodiment is an imaging device such as a CCD (Charge Coupled Devices) camera or a CMOS (Complementary Metal Oxide Semiconductor) camera. The monitoring assistance device 20 may also be a mirror, as long as the driver can adequately see the area around the vehicle's forward travel surface, including the front wheels 3F, from the driver's seat 4A.

[0075] The monitoring assistance device 20 is provided on the tank stay 12. In this embodiment, the monitoring assistance device 20 is provided on the front support legs 52F of the tank stay 12. The monitoring assistance device 20 is provided on the left and right front support legs 52F, respectively. In this way, the monitoring assistance device 20 is positioned in front of the driver's seat 4A.

[0076] The monitoring assistance device 20 is connected to the front support leg 52F via an auxiliary bracket 23. The auxiliary bracket 23 extends from the front support leg 52F outward in the left-right direction of the vehicle body 2. The monitoring assistance device 20 is connected and supported by the auxiliary bracket 23. That is, the monitoring assistance device 20 is located on the side of the bonnet 5. In this way, the monitoring assistance device 20 is located in front of the driver's seat 4A and at a height between the vehicle body frame 2A and the tank cover 13.

[0077] The monitoring support device 20 is connected to the auxiliary bracket 23 in a position-adjustable manner. The monitoring support device 20 is configured to be fixable at any position between the base end and the tip end of the auxiliary bracket 23. In this way, the imaging range of the monitoring support device 20 can be arbitrarily changed by adjusting its mounting position on the auxiliary bracket 23.

[0078] As shown in Figures 3 and 11, the tractor 1 is equipped with an image output device 25. The image output device 25 is a video output monitor that outputs video captured by the monitoring support device (imaging device) 22. In this embodiment, the image output device 25 includes a left monitor 25L and a right monitor 25R.

[0079] The left monitor 25L is positioned adjacent to the front left side of the steering wheel 4B. The right monitor 25R is positioned adjacent to the front right side of the steering wheel 4B. Therefore, when the driver looks from the driver's seat 4A towards the front wheels 3F, the image output devices 25 naturally come into their field of view. For example, when the driver turns the steering wheel 4B to the left to turn the tractor 1 to the left, the left monitor 25L naturally comes into the driver's field of view. Also, when the driver turns the steering wheel 4B to the right to turn the tractor 1 to the right, the right monitor 25R naturally comes into the driver's field of view. This enables high maneuverability.

[0080] Furthermore, as long as maneuverability is not compromised, both the left monitor 25L and the right monitor 25R may be positioned on either the front left or right side of the steering wheel 4B, or they may be positioned in front of the center of the steering wheel 4B. In addition, the image output device 25 may output various information such as driving information of the tractor 1, operation information of the work equipment, field maps, work information, and weather information, in addition to the video captured by the monitoring assistance device 20.

[0081] <Modification> In the above embodiment, the monitoring assistance device 20 is provided on the tank stay 12, but it may also be provided on the tank cover 13. That is, the monitoring assistance device 20 may be provided above the bonnet 5. As shown in Figures 12 to 14, in the tractor 1 of this first modification, the monitoring assistance device 20 is provided at the bottom of the tank cover 13.

[0082] The auxiliary bracket 23 extends outward in the left-right direction of the vehicle body 2 along the lower cover 13U of the tank cover 13, at a position towards the front of the lower cover 13U. The monitoring auxiliary device 20 is connected to and supported by the auxiliary bracket 23. Thus, the monitoring auxiliary device 20 is provided at a position towards the front of the lower cover 13U of the tank cover 13.

[0083] As shown in Figure 13, the monitoring support device 20 is located behind the front end of the lower cover 13U. As shown in Figure 14, the monitoring support device 20 is located on the side of the lower cover 13U that is centered between the left and right ends of the lower cover 13U. Thus, the monitoring support device 20 is located inside the outer circumference of the lower part of the tank cover 13.

[0084] As a result, the driver can get a bird's-eye view of the area around the tractor 1's forward travel surface, including the front wheels 3F, from above the driver's seat 4A (below the tank cover 13), thus achieving even better maneuverability. Moreover, with this first modified tractor 1, even during rainfall or snowfall, rain or snow is less likely to adhere to the monitoring support device 20, allowing the driver to clearly see the area around the forward travel surface. Therefore, even better maneuverability is achieved.

[0085] As shown in Figures 15 to 17, in this second modified tractor 1, the monitoring support device 20 is provided on the side of the tank cover 13. The auxiliary bracket 23 extends outward in the left-right direction of the side cover 13S at a position towards the front of the side cover 13S of the tank cover 13. The monitoring support device 20 is connected and supported by the auxiliary bracket 23.

[0086] As described above, the monitoring assistance device 20 is installed in a position towards the front of the side cover 13S of the tank cover 13. This makes it less likely for the monitoring assistance device 20 itself to obstruct the driver's view, and the driver can get a bird's-eye view of the area around the forward travel surface of the tractor 1, including the front wheels 3F, from above the driver's seat 4A (below the tank cover 13), resulting in even better maneuverability.

[0087] In the above embodiment, the monitoring support device 20 is provided on the tank stay 12, but it may also be provided on the bonnet 5. As shown in Figures 18 to 20, in the tractor 1 of this third modification, the monitoring support device 20 is provided on the side of the bonnet 5. The auxiliary bracket 23 extends outward in the left-right direction from the side of the bonnet 5. The monitoring support device 20 is connected and supported by the auxiliary bracket 23.

[0088] As a result, even with a large bonnet 5, the driver can get a bird's-eye view of the area around the tractor 1's forward travel surface, including the front wheels 3F, from above the driver's seat 4A (below the tank cover 13), thus achieving even better maneuverability.

[0089] In the above embodiment, the front support leg 52F of the tank stay 12 extends toward the front of the vehicle body 2 from a position near the lower end of the middle portion between the upper and lower parts of the central support leg 52C, but it may also extend diagonally downward and forward from the end of the front frame portion 51F of the base frame 51.

[0090] As shown in Figures 21 and 22, in the tractor 1 of this fourth modified example, the front support leg 52F of the tank stay 12 extends diagonally downward and forward from the end of the front frame portion 51F of the base frame 51, passes along the side of the bonnet 5, and is connected to the front stay mounting portion 24F. That is, the front support leg 52F extends from the front of the vehicle body frame 2A, passes along the side of the bonnet 5, and is above the driver's seat 4A. As shown in Figure 21, the monitoring assistance device 20 is provided near the upper end of the front support leg 52F.

[0091] As a result, even if the bonnet 5 is large, the driver can see the area around the tractor 1's forward travel surface, including the front wheels 3F, from the side of the bonnet 5, making it possible to operate the tractor 1 more appropriately.

[0092] As shown in Figure 23, the monitoring assistance device 20 may be provided on the combination lamp 22. That is, in the tractor 1 of this fifth modification, the monitoring assistance device 20 is provided on the cabin 6 via the combination lamp 22. The auxiliary bracket 23 extends outward in the left-right direction from the base frame of the combination lamp 22 to the bonnet 5. The monitoring assistance device 20 is connected and supported by the auxiliary bracket 23.

[0093] This allows the driver to see the area around the tractor 1's forward travel surface, including the front wheels 3F, from a position close to the front wheels 3F. As a result, even better maneuverability is achieved.

[0094] The monitoring assistance device 20 may be a mirror. For example, as shown in Figure 24, in the tractor 1 of this sixth modification, similar to the tractor 1 of this fifth modification, the front support leg 52F extends from the front of the vehicle frame 2A, through the side of the bonnet 5, and above the driver's seat 4A. The mirror (monitoring assistance device 20) is provided at a position near the upper end on the side of the front support leg 52F.

[0095] As a result, the driver can see the area around the tractor 1's forward travel surface, including the front wheels 3F, through the reflected image in the mirror, allowing for a more natural feel when operating the tractor 1.

[0096] The above-mentioned mirror (monitoring support device 20) may be provided at the respective positions of the monitoring support device 20 in the tractor 1 of the first modified example, the second modified example, and the third modified example, as shown in Figures 12 to 20.

[0097] The present invention provides a tractor 1 as described in the following items.

[0098] (Item 1) A tractor 1 comprising a body frame 2A, a running gear 3 including front wheels 3F and supporting the body frame 2A so as to be able to move, a driver's seat 4A provided on the body frame 2A, a support device S provided on the body frame 2A, a power supply device 7 supported by the support device S, and a monitoring assistance device 20 provided on the support device, which enables the driver to see the area around the forward travel surface of the vehicle, including the front wheels 3F, from the driver's seat 4A.

[0099] According to the tractor 1 described in item 1, the driver can visually confirm the area around the vehicle's forward travel surface, including the front wheels 3F, using the monitoring and assistance device 20, thereby enabling the driver to appropriately maneuver the tractor 1 along the desired travel path.

[0100] (Item 2) The tractor 1 according to Item 1, wherein a bonnet 5 is provided in front of the driver's seat 4A and covers the front of the vehicle frame 2A, and the monitoring assistance device 20 is provided to the side of the bonnet 5.

[0101] According to the tractor 1 described in item 2, even with a large bonnet 5 in the vertical direction, the driver can see the area around the vehicle's forward travel surface, including the front wheels 3F, from the driver's seat 4A. Therefore, it becomes possible to properly operate the tractor 1.

[0102] (Item 3) The tractor 1 according to Item 1 or Item 2, wherein a bonnet 5 is provided in front of the driver's seat 4A and covers the front of the vehicle frame 2A, and the monitoring assistance device 20 is provided above the bonnet 5.

[0103] According to the tractor 1 described in item 3, even though it has a large bonnet 5 in the left-right direction, the driver can see the area around the vehicle's forward travel surface, including the front wheels 3F, from the driver's seat 4A. Therefore, it becomes possible to properly operate the tractor 1.

[0104] (Item 4) The tractor 1 according to any one of items 1 to 3, wherein the power supply device 7 includes a tank 9 for storing gas for power generation, the support device S includes a tank stay 12 erected on the vehicle frame 2A and supporting the tank 9 above the driver's seat 4A, and the monitoring auxiliary device 20 is provided on the tank stay 12.

[0105] According to the tractor 1 described in item 4, the driver can see the area around the vehicle's forward travel surface, including the front wheels 3F, from above the driver's seat 4A, enabling more appropriate operation of the tractor 1. Moreover, the tank stay 12, which supports the heavy tank 9, is robustly constructed. Therefore, by installing the monitoring assistance device 20 on the tank stay 12, as in the tractor 1 described in item 4, vibrations of the monitoring assistance device 20 during driving can be suppressed. This results in even better visibility and enables more appropriate operation of the tractor 1.

[0106] (Item 5) The tractor 1 according to Item 4, comprising a bonnet 5 provided in front of the driver's seat 4A and covering the front of the vehicle frame 2A, wherein the tank stay 12 includes a front support leg 52F extending from the front of the vehicle frame 2A through the side of the bonnet 5 to above the driver's seat 4A, and the monitoring assist device 20 is provided on the front support leg 52F.

[0107] According to the tractor 1 in item 5, the driver can see the area around the vehicle's forward travel surface, including the front wheels 3F, from the side of the bonnet 5, making it possible to operate the tractor 1 more appropriately.

[0108] (Item 6) The tractor 1 according to Item 4 or 5, wherein the support device S includes a tank cover 13 that covers the tank 9, and the monitoring auxiliary device 20 is provided on the tank cover 13.

[0109] According to tractor 1 in item 6, the driver can get an overhead view of the area around the vehicle's forward travel surface, including the front wheels 3F, from above the driver's seat 4A, thus providing even better maneuverability.

[0110] (Item 7) The tractor 1 described in Item 6, wherein the monitoring support device 20 is provided at the lower part of the tank cover 13.

[0111] According to the tractor 1 described in item 7, rain and snow are less likely to adhere to the monitoring support device 20, even during rainfall or snowfall, allowing the driver to clearly see the area around the vehicle's forward travel surface, including the front wheels 3F. As a result, even better maneuverability is achieved.

[0112] (Item 8) The tractor 1 described in Item 6, wherein the monitoring support device 20 is provided on the side of the tank cover 13.

[0113] According to the tractor 1 described in item 8, the monitoring assistance device 20 itself is less likely to obstruct the driver's view, thus enabling the driver to operate the tractor 1 more appropriately.

[0114] (Item 9) The tractor 1 according to any one of items 1 to 8, wherein the power supply device 7 includes a tank 9 for storing gas for power generation and a fuel cell 10 for generating electricity using the gas, the support device S includes a tank stay 12 erected on the vehicle frame 2A and supporting the tank 9 above the driver's seat 4A, and a tank cover 13 covering the tank 9, and the monitoring support device 20 is located in front of the driver's seat 4A and at a height between the vehicle frame 2A and the tank cover 13.

[0115] According to the tractor 1 described in item 9, the driver can see the area around the vehicle's forward travel surface, including the front wheels 3F, from a position close to the driver's line of sight while seated in the driver's seat 4A, making it possible to operate the tractor 1 with a more natural feel.

[0116] (Item 10) The tractor 1 according to Item 9, comprising a bonnet 5 provided in front of the driver's seat 4A and covering the front part of the vehicle frame 2A, the fuel cell 10 being supported inside the bonnet 5 on the vehicle frame 2A, and the monitoring support device 20 being provided on the side of the bonnet 5.

[0117] According to the tractor 1 of item 10, even if the bonnet 5 becomes larger as the fuel cell 10 is enlarged, the driver can still see the area around the vehicle's forward travel surface, including the front wheels 3F, from the side of the bonnet 5, making it possible to operate the tractor 1 more appropriately.

[0118] (Item 11) The monitoring assistance device 20 is a mirror, as described in any one of Items 1 to 10.

[0119] According to the tractor 1 in item 11, the driver can see the area around the vehicle's forward travel surface, including the front wheels 3F, through the reflected image in the mirror, making it possible to operate the tractor 1 with a more natural feel.

[0120] (Item 12) The tractor 1 according to any one of items 1 to 11, wherein the monitoring assistance device 20 is an imaging device that captures images of the area around the forward travel surface.

[0121] According to the tractor 1 in item 12, the imaging device offers greater flexibility in placement compared to mirrors and can be configured to more effectively visualize the area around the vehicle's forward travel surface, including the front wheels 3F. This allows the driver to operate the tractor 1 more appropriately.

[0122] (Item 13) The tractor 1 according to Item 12, comprising: a cabin 6 provided on the vehicle frame 2A and housing the driver's seat 4A; a steering wheel 4B provided inside the cabin 6; and an image output device 25 provided inside the cabin 6 and outputting images captured by the monitoring assistance device 20, wherein the image output device 25 is provided in front of the driver's seat 4A and to the left and right of the steering wheel 4B.

[0123] According to the tractor 1 in item 13, the driver can see the area around the vehicle's forward travel surface, including the front wheels 3F, from the left and right positions of the steering wheel 4B. Therefore, the driver can operate the tractor 1 with a more natural feel without having to move their eyes significantly.

[0124] Having described the present invention above, the embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than the foregoing description, and all modifications within the meaning and scope of equivalents of the claims are intended to be included.

[0125] 1. Tractor 2. Body 2A. Body frame 3. Running gear 4A. Driver's seat 4B. Steering wheel 5. Bonnet 6. Cabin 7. Power supply device 8. Electric motor 9. Tank 10. Fuel cell stack 12. Tank stay 13. Tank cover 20. Monitoring support device 25. Image output device S. Support device

Claims

1. A tractor comprising: a body frame; a running gear including front wheels and supporting the body frame so as to be drivable; a driver's seat provided on the body frame; a support device provided on the body frame; a power supply device supported by the support device; and a monitoring assistance device provided on the support device, which enables the driver to visually observe the area around the forward running surface of the vehicle, including the front wheels, from the driver's seat.

2. The tractor according to claim 1, comprising a bonnet provided in front of the driver's seat and covering the front part of the vehicle frame, wherein the monitoring assistance device is provided to the side of the bonnet.

3. The tractor according to claim 1, comprising a bonnet provided in front of the driver's seat and covering the front part of the vehicle frame, wherein the monitoring assistance device is provided above the bonnet.

4. The tractor according to claim 1, wherein the power supply device includes a tank for storing gas for power generation, the support device includes a tank stay erected on the vehicle frame and supporting the tank above the driver's seat, and the monitoring support device is provided on the tank stay.

5. The tractor according to claim 4, comprising a bonnet located in front of the driver's seat and covering the front of the vehicle frame, wherein the tank stay includes a front support leg extending from the front of the vehicle frame through the side of the bonnet to above the driver's seat, and the monitoring assist device is provided on the front support leg.

6. The tractor according to claim 4, wherein the support device includes a tank cover that covers the tank, and the monitoring auxiliary device is provided on the tank cover.

7. The tractor according to claim 6, wherein the monitoring support device is provided at the lower part of the tank cover.

8. The tractor according to claim 6, wherein the monitoring assistance device is provided on the side of the tank cover.

9. The tractor according to claim 1, wherein the power supply device includes a tank for storing gas for power generation and a fuel cell for generating electricity using the gas, the support device includes a tank stay erected on the vehicle frame and supporting the tank above the driver's seat and a tank cover covering the tank, and the monitoring support device is located in front of the driver's seat and at a height between the vehicle frame and the tank cover.

10. The tractor according to claim 9, comprising a bonnet located in front of the driver's seat and covering the front part of the vehicle frame, wherein the fuel cell is supported inside the bonnet on the vehicle frame, and the monitoring assistance device is provided on the side of the bonnet.

11. The tractor according to any one of claims 1 to 10, wherein the monitoring assistance device is a mirror.

12. The tractor according to any one of claims 1 to 10, wherein the monitoring assistance device is an imaging device that captures images of the area around the forward travel surface.

13. The tractor according to claim 12, comprising: a cabin provided on the vehicle frame and housing the driver's seat; a steering wheel provided inside the cabin; and an image output device provided inside the cabin and outputting images captured by the monitoring assistance device, wherein the image output device is provided in front of the driver's seat and to the left and right of the steering wheel.

Images