JP2020162281A - Work vehicle - Google Patents

Abstract

To provide a technique capable of suppressing performance deterioration and damage of a fuel cell caused by air shortage in a cathode electrode without reducing responsiveness of output generated by the fuel cell to an electric power load in a work vehicle whose electric power source is electric power generated by the fuel cell.SOLUTION: A work vehicle comprises: a turning start detection part for detecting turning start operation that turns a vehicle body; and a load increase determining part for determining whether or not the increase of an electric power load of a fuel cell is in a predicted load increased state on the basis of the result detected by the turning start detection part. A target oxidant gas supply amount when an oxidant gas supply control part determines that the load increase determining part is in the load increased state, is set to be larger than that when the load increase determining part is not in the load increased state.SELECTED DRAWING: Figure 7

Description

The present invention relates to a work vehicle including a fuel cell that generates electricity by an electrochemical reaction between a fuel gas and an oxidant gas, and using the generated power of the fuel cell as a power source.

As a vehicle that obtains running power from the generated power of the fuel cell, the power load (required power) is calculated from the accelerator position, and power is generated to the fuel cell so that the generated power output of the fuel cell follows the calculated power load. It is known that the supply amounts of fuel for power generation and air for power generation (an example of an oxidizing agent gas) are controlled (see, for example, Patent Document 1).
Further, in the vehicle described in Patent Document 1, an air supply pump that supplies air to the fuel cell when the rate of change of the electric power load calculated from the accelerator position rises by a predetermined value or more (an example of an oxidant gas supply unit). By setting the torque command value used for the control of the above power load to be larger than that calculated by the above power load, the responsiveness of the air supply pump is improved.

Japanese Unexamined Patent Publication No. 2016-96681

In a work vehicle having a vehicle body on which a work machine can be mounted, most of the generated power of the fuel cell is not consumed as a driving source for traveling as in an automobile, but is mounted on the vehicle body in addition to the driving source for traveling. It is also used as a drive source for working machines. Therefore, in the work vehicle, the electric power load may increase sharply regardless of the accelerator position, and the amount of air for power generation from the air supply pump to the fuel cell is quickly tracked against the increase in the electric power load. It may not be possible to increase it. In such a case, the responsiveness of the power generation output of the fuel cell to the power load is lowered, and so-called air withering occurs in which the air is exhausted at the cathode electrode of the fuel cell, resulting in deterioration or damage of the fuel cell performance. There is a risk of inviting.

In view of this situation, the main problem of the present invention is to cause air withering at the cathode electrode in a work vehicle using the generated power of the fuel cell as a power source without deteriorating the responsiveness of the generated output of the fuel cell to the power load. The point is to provide a technology that can suppress the performance deterioration and damage of the fuel cell caused by it.

The first characteristic configuration of the present invention is a fuel cell that generates electricity by an electrochemical reaction between a fuel gas and an oxidant gas.
An electric motor for traveling that generates a traveling force of a vehicle body on which a work machine can be mounted by the generated power of the fuel cell.
An oxidant gas supply unit that supplies the oxidant gas to the fuel cell,
A work vehicle including an oxidant gas supply control unit that controls the oxidant gas supply unit so that the oxidant gas supply amount to the fuel cell becomes a target oxidant gas supply amount.
A turning start detection unit that detects a turning start operation for turning the vehicle body,
A load increase determining unit for determining whether or not an increase in the power load of the fuel cell is predicted based on the detection result of the turning start detecting unit is provided.
When the target oxidant gas supply amount when the oxidant gas supply control unit determines that the load increase determination unit is in the load increase state is determined by the load increase determination unit to not be in the load increase state. The point is to set it larger than.

According to this configuration, in the above-mentioned oxidant gas supply control unit, when controlling the oxidant gas supply unit such as an air supply pump so that the oxidant gas supply amount to the fuel cell becomes the target oxidant gas supply amount. When the load increase determination unit determines that the load is increasing, the target oxidant gas supply amount is set to be larger than when the load increase determination unit determines that the load is not increasing. To. Therefore, for fuel cells in which the power load is likely to increase, the amount of oxidant gas supplied is increased in advance in anticipation of this, thereby increasing while preventing air withering of the cathode electrode. It is possible to quickly follow the power generation output of the fuel cell with respect to the power load.

Further, when the turning start operation is input, the rotational load of the traveling electric motor increases due to the subsequent turning of the vehicle body, and the power load of the fuel cell that supplies the generated power to the traveling electric motor is increased accordingly. To increase.
Therefore, according to this configuration, the state in which the turning start operation is detected by the turning start detection unit in the load increase determination unit is a load increase state in which an increase in the power load of the fuel cell is predicted. Based on the detection result of the turning start detection unit, it can be determined whether or not the load is increased.
Then, in controlling the oxidant gas supply unit such as an air supply pump so that the oxidant gas supply amount to the fuel cell becomes the target oxidant gas supply amount in the oxidant gas supply control unit, the turning start detection is performed. When the turning start operation is detected by the unit and the load increase determination unit determines that the load is increasing, the target oxidant is more than the case where the load increase determination unit determines that the load is not increasing. It is set to one with a large gas supply amount. Therefore, for fuel cells in which the power load is likely to increase due to the turning of the vehicle body, by predicting this and increasing the supply amount of oxidizing agent gas in advance, the air withered at the cathode electrode. It is possible to quickly follow the power generation output of the fuel cell with respect to the increasing power load, and improve the responsiveness of the power generation output to the turning start operation of the vehicle body.

Therefore, according to the present invention, in a work vehicle powered by the power generated by the fuel cell, the performance of the fuel cell due to air withering at the cathode electrode without deteriorating the responsiveness of the power generation output of the fuel cell to the power load. It is possible to provide a technique capable of suppressing deterioration and damage.

The second characteristic configuration of the present invention includes a vehicle speed detection unit that detects the vehicle speed of the vehicle body.
The target oxidant gas supply amount when the oxidant gas supply control unit determines that the load increase determination unit is in the load increase state is set according to the vehicle speed of the vehicle body detected by the vehicle speed detection unit. There is a point to set.

According to this configuration, the oxidant gas supply control unit appropriately sets the target oxidant gas supply amount according to the vehicle speed of the vehicle body detected by the vehicle speed detection unit, and the oxidant gas supply amount to the fuel cell is the relevant amount. The oxidant gas supply unit is controlled so as to reach the set target oxidant gas supply amount. Therefore, when the vehicle speed is low, the rate of increase in the power load is smaller than when the vehicle speed is high. Therefore, the target oxidant gas supply amount when the vehicle speed is low is set to be higher than when the vehicle speed is high. By setting the value to a small value, it is possible to avoid an unnecessary increase in the supply amount of the oxidant gas to the fuel cell and suppress the waste of energy consumption of the oxidant gas and the oxidant gas supply unit for supplying the oxidant gas. it can.

The third characteristic configuration of the present invention includes a steering control unit that determines a turning mode to be executed when the vehicle body turns from a plurality of turning modes.
The target oxidant gas supply amount when the oxidant gas supply control unit determines that the load increase determination unit is in the load increase state is set according to the turning mode determined by the steering control unit. There is a point to do.

According to this configuration, in the oxidant gas supply control unit, the target oxidant gas supply amount is appropriately set according to the turning mode executed when the vehicle body turns, which is determined by the steering control unit, and the oxidant to the fuel cell. The oxidant gas supply unit is controlled so that the gas supply amount becomes the set target oxidant gas supply amount. Therefore, by setting the target oxidant gas supply amount when turning in the turning mode where the increase rate of the power load is relatively small, to be smaller than when turning in the turning mode where the increase rate of the power load is relatively large, the fuel It is possible to avoid an unnecessary increase in the amount of the oxidant gas supplied to the battery, and to suppress the waste of the oxidant gas and the energy consumption of the oxidant gas supply unit for supplying the oxidant gas.

In addition to the above-mentioned third feature configuration, the fourth feature configuration of the present invention is configured as a wheel traveling type in which the left and right front wheels and the left and right rear wheels are driven to travel.
The plurality of turning modes include a two-wheel drive turning mode in which transmission to the left and right front wheels is blocked and only the left and right rear wheels are driven to turn the vehicle body, and the left and right front wheels and the left and right rear wheels. A four-wheel drive turning mode in which the vehicle body is driven at a constant speed, and the left and right front wheels and the left and right rear wheels so that the peripheral speeds of the left and right front wheels are faster than the peripheral speeds of the left and right rear wheels. It has a front wheel speed-up turning mode in which the wheels are driven to turn the vehicle body and an auto-brake mode in which the rear wheels on the inside of the turning are braked to turn the vehicle body.

According to this configuration, even in a wheel-traveling work vehicle in which the left and right front wheels and the left and right rear wheels are driven by the power generated by the fuel cell as a power source, the two wheels are prevented from withering air in the cathode electrodes. It is possible to improve the responsiveness of the power generation output to the turning start operation in the driving turning mode, the four-wheel driving turning mode, the front wheel speed-up turning mode, and the various turning modes of the auto brake mode.
For example, the target oxidant gas supply amount when turning in the two-wheel drive turning mode or the four-wheel drive turning mode in which the power load increase rate is relatively small is turned in the front wheel speed-up turning mode in which the power load increase rate is relatively large. By setting it smaller than when it is used, it is possible to avoid an unnecessary increase in the amount of oxidant gas supplied to the fuel cell and suppress the waste of energy consumed by the oxidant gas and the oxidant gas supply unit for supplying it. can do.
Further, in various turning modes, it is possible to switch whether or not to select the autobrake mode in which the rear wheels on the inner side of turning are braked to reduce the turning radius. Then, by setting the target oxidant gas supply amount when the auto brake mode is deselected to be smaller than that when the auto brake mode is selected, in which the rate of increase in the power load is relatively larger than that at that time, the fuel cell is oxidized. It is possible to avoid an unnecessary increase in the supply amount of the agent gas and suppress the waste of energy consumption of the oxidant gas and the oxidant gas supply unit for supplying the oxidant gas.

In addition to the above-mentioned third feature configuration, the fifth feature configuration of the present invention is configured as a crawler traveling type in which the left and right crawlers are driven to travel.
The plurality of turning modes include a slow turning mode in which the steering-side roller is decelerated to turn the vehicle body, and a brake turning mode in which the steering-side roller is stopped to turn the vehicle body. It has a spin turning mode in which the roller on the opposite side is reversed to turn the vehicle body.

According to this configuration, even in a crawler traveling type work vehicle in which the left and right crawlers are driven by the power generated by the fuel cell as a power source, the slow turning mode and the brake are performed while preventing the air withering of the cathode electrodes. It is possible to improve the responsiveness of the power generation output to the turning start operation in the turning mode and the various turning modes of the spin turning mode. Then, for example, the target oxidant gas supply amount when turning in the slow turning mode or the brake turning mode in which the increase rate of the power load is relatively small is set to be higher than that in the spin turning mode in which the increase rate of the power load is relatively large. By setting the value to a small value, it is possible to avoid an unnecessary increase in the amount of oxidant gas supplied to the fuel cell and suppress the waste of energy consumed by the oxidant gas and the oxidant gas supply unit for supplying the oxidant gas. it can.

The sixth characteristic configuration of the present invention is a steering angle sensor in which the turning start detection unit detects a steering angle.
The point is that the load increase determination unit determines that the load increase state is obtained when the steering angle detected by the steering angle sensor is equal to or greater than the set steering angle.

When the steering angle detected by the steering angle sensor exceeds the set steering angle, the rotational load of the traveling electric motor suddenly increases due to the subsequent sharp turning, and the generated power is supplied to the traveling electric motor accordingly. The power generation load of the fuel cell to be supplied increases sharply.
Therefore, according to this configuration, in the load increase determination unit, the sudden turning state in which the steering angle equal to or larger than the set steering angle is detected by the steering angle sensor is the load increase state in which the power load of the fuel cell is predicted to increase rapidly. In this form, it is possible to determine whether or not the load is increased based on the detection result of the turning start detection unit.
Then, in controlling the oxidant gas supply unit such as an air supply pump so that the oxidant gas supply amount to the fuel cell becomes the target oxidant gas supply amount in the oxidant gas supply control unit, the sharp turning state When the turning start operation is detected and the load increase determination unit determines that the load is increasing, the target oxidant is more than the case where the load increase determination unit determines that the load is not increasing. It is set to one with a large gas supply amount. Therefore, for fuel cells in which the power load is likely to increase sharply due to sharp turning, by predicting this and increasing the supply amount of oxidizing agent gas in advance, air withering of the cathode electrode can be prevented. While preventing this, it is possible to quickly follow the power generation output of the fuel cell with respect to the rapidly increasing electric power load, and improve the responsiveness of the sharp turning of the vehicle body.

The seventh feature configuration of the present invention includes an automatic traveling control unit that automatically travels the vehicle body along a preset target route based on the current position of the vehicle body measured by using a satellite positioning system.
The turning start detection unit is at a point of detecting a turning start operation during automatic driving by the automatic driving control unit.

According to this configuration, when automatic driving is performed by the automatic driving control unit, the turning start detection unit can detect automatic driving at the turning unit included in the target path as a turning start operation of the vehicle body. it can. Then, in the load increase determination unit, the state in which the turning start operation accompanying the automatic driving is detected by the turning start detection unit can be determined as a load increase state in which an increase in the power load of the fuel cell is predicted. ..

The figure which shows the schematic structure of the work vehicle The figure which shows the structure of the driving part inside a cabin Schematic diagram showing the transmission configuration of a tractor Block diagram showing the schematic configuration of the work vehicle Block diagram showing a schematic configuration of a work vehicle control system Air supply control flow chart Flow diagram of turning judgment processing Work equipment judgment processing flow chart

Hereinafter, as an example of the embodiment for carrying out the present invention, an embodiment in which the work vehicle according to the present invention is applied to the tractor 1 will be described with reference to the drawings.
The work vehicle according to the present invention includes passenger work vehicles other than tractors, such as passenger mowers, passenger rice transplanters, combines, snowplows, wheel loaders, and unmanned work vehicles such as unmanned cultivators and unmanned mowers. It can be applied to vehicles.

As shown in FIG. 1, the tractor 1 includes a fuel cell 8A that generates electricity by an electrochemical reaction between a fuel gas and an oxidant gas, and is configured to use the generated power of the fuel cell 8A as a power source.
More specifically, as shown in FIGS. 4 and 5, the tractor 1 includes a fuel cell system 8 having a fuel cell 8A, and the traveling force of the vehicle body and the vehicle body mounted on the vehicle body by the generated power of the fuel cell 8A, which will be described later. An electric motor 13 (an example of a traveling electric motor and a working electric motor) that generates a driving force for a working machine such as a rotary tiller 3 and a fuel cell control unit 46A that controls the operation of the fuel cell system 8 are provided. Has been done.

The fuel cell system 8 includes an air supply unit 8B (an example of an oxidant gas supply unit) that supplies air as an oxidant gas to the cathode electrode of the fuel cell 8A, and hydrogen to the anode electrode of the fuel cell 8A. A fuel gas supply unit 8C for supplying a fuel gas such as gas is provided.
The air supply unit 8B is composed of an air pump or the like that sends the air taken in from the outside air to the cathode electrode of the fuel cell 8A. The air supply control unit 46A1 (an example of the oxidant gas supply control unit) in which the fuel cell control unit 46A functions controls the rotation speed of the air pump constituting the air supply unit 8B to the cathode electrode of the fuel cell 8A. The air supply amount is adjustable.
The fuel gas supply unit 8C includes a hydrogen cylinder that stores hydrogen gas, which is a fuel gas, in a high pressure state, and a hydrogen supply valve that adjusts the flow rate of the fuel gas introduced from the hydrogen cylinder to the anode electrode of the fuel cell 8A. Has been done. The fuel gas supply control unit 46A2 in which the fuel cell control unit 46A functions controls the opening degree of the hydrogen supply valve constituting the fuel gas supply unit 8C to adjust the fuel gas supply amount to the anode electrode of the fuel cell 8A. It is configured to be possible.
Further, the load increase determination unit 46A3 in which the fuel cell control unit 46A functions performs a load increase determination process in which a rapid increase in the power load of the fuel cell 8A is expected, although the details will be described later.

As shown in FIG. 1, a rotary tiller 3 which is an example of a working machine is connected to the tractor 1 illustrated in the present embodiment via a three-point link mechanism 2 at the rear portion. As a result, the tractor 1 is configured to have a rotary tillage specification in which the tillage work is performed by the rotary tillage device 3 connected to the rear portion. The rotary tiller 3 is connected to the rear part of the tractor 1 so as to be able to move up and down and roll, and is driven by the power from the tractor 1.
In addition, instead of the rotary tiller 3, various working machines such as a plow, a disc halo, a cultivator, a subsoiler, a mowing device, a sowing device, and a fertilizer application device can be connected to the rear part of the tractor 1.

As shown in FIGS. 1, 4, and 5, a mobile communication terminal 5 which is an example of a wireless communication device set to communicate wirelessly with an in-vehicle control unit 46 mounted on the tractor 1 is provided. The mobile communication terminal 5 is provided with a multi-touch type display device (for example, a liquid crystal panel) 5A that enables various information displays and input operations related to automatic driving.
A tablet-type personal computer, a smartphone, or the like can be adopted as the mobile communication terminal 5. Further, for wireless communication, wireless LAN (Local Area Network) such as Wi-Fi (registered trademark) and short-range wireless communication such as Bluet1oth (registered trademark) can be adopted. Further, the tractor 1 side may be equipped with a converter or the like that converts the data received by Wi-Fi into data that can be communicated by CAN (Control Area Network).

As shown in FIG. 1, the tractor 1 is provided with a front frame 10 arranged in front of the tractor 1, a bonnet 16, a cabin 17 arranged in the rear part of the tractor 1, and the like. Further, the tractor 1 is configured as a wheel traveling type in which the tractor 1 is driven by the steerable and driveable left and right front wheels 11 and the driveable left and right rear wheels 12.
Further, as shown in FIG. 3, the tractor 1 is provided with a main clutch 14 that interrupts the power from the electric motor 13, a transmission unit 15 that shifts the power via the main clutch 14, and the like.
The left and right front wheels 11 are steerably connected to the left and right ends of the front axle case 18 which is rotatably supported by the front frame 10 via the left and right front wheel gear cases 19. The left and right rear wheels 12 are supported by left and right rear axle cases (not shown) provided at the rear of the transmission unit 15.

The speed change unit 15 has a traveling transmission system 15A for shifting the power from the electric motor 13 for traveling and a work transmission system 15B for shifting the power for work.
The traveling transmission system 15A includes an electronically controlled main transmission 20 that shifts the power from the electric motor 13, and an electrohydraulic control type forward / backward switching device that switches the power from the main transmission 20 between forward and reverse. 21. Gear type auxiliary transmission 22 that shifts the forward or reverse power from the forward / backward switching device 21 to two high and low speeds, and the forward or reverse power from the forward / backward switching device 21 to the ultra-low speed. The power from the gear-type creep transmission 23, the auxiliary transmission 22, or the creep transmission 23 for shifting gears is distributed to the left and right rear wheels 12, and the power from the rear wheel differential 24 and the rear wheel differential 24 is distributed. Includes left and right speed reducers 25 that decelerate and transmit to the left and right rear wheels 12, and an electro-hydraulic control type power transmission switching device 26 that switches transmission from the auxiliary transmission 22 or creep transmission 23 to the left and right front wheels 11. It has been.

The work transmission system 15B includes a hydraulic PTO clutch 27 that interrupts the power from the electric motor 13, a PTO transmission 28 that switches the power via the PTO clutch 27 between three forward speeds and one reverse speed, and a PTO. The PTO shaft 29, which outputs the power from the transmission 28 for work, and the like are included.

The speed change unit 15 is provided with left and right brakes 30 that individually brake the left and right rear wheels 12. In the present embodiment, the power for traveling (for rotating the front wheels 11 and the rear wheels 12) and the power for driving the working machine (rotary tillage device 3) are obtained from the same electric motor 13. , These may be obtained from another electric motor.

The main transmission 20 includes an I-HMT (Integrated Hydro-static Continuously Variable Transmission), which is an example of a hydraulic mechanical continuously variable transmission having higher transmission efficiency than a hydrostatic continuously variable transmission (HST). It has been adopted.
Instead of the I-HMT, the main transmission 20 includes an HMT (Hydraulic Mechanical Transition), a hydrostatic continuously variable transmission, or a belt-type continuously variable transmission, which is an example of a hydraulic mechanical continuously variable transmission. A continuously variable transmission such as, may be adopted. Further, instead of the continuously variable transmission, an electro-hydraulic control type stepped transmission having a plurality of hydraulic speed change clutches and a plurality of electromagnetic speed change valves for controlling the flow of oil with respect to them is adopted. You may.

The transmission switching device 26 sets the transmission state to the left and right front wheels 11 to the transmission cutoff state in which the transmission to the left and right front wheels 11 is blocked, and the peripheral speeds of the left and right front wheels 11 are the same as the peripheral speeds of the left and right rear wheels 12. The constant velocity transmission state that is transmitted to the left and right front wheels 11 and the front wheels that are transmitted to the left and right front wheels 11 so that the peripheral speed of the left and right front wheels 11 is about twice the peripheral speed of the left and right rear wheels 12. Switch to the double speed transmission state (an example of the front wheel speed increase transmission state). The power from the transmission switching device 26 is transmitted to the front wheel differential device 32 built in the front axle case 18 via the transmission shaft 31 for driving the front wheels and the like. The front wheel differential device 32 distributes the power from the transmission switching device 26 to the left and right front wheels 11. The distributed power is transmitted to the left and right front wheels 11 via the left and right transmission devices (not shown) built in the left and right front wheel gear cases 19. The left and right transmission devices reduce the power from the front wheel differential device 32 and transmit the power to the left and right front wheels 11 while allowing the left and right front wheels 11 to steer. The power taken out from the PTO shaft 29 is transmitted to the rotary tiller 3 via an external transmission shaft (not shown) or the like.

As shown in FIGS. 1 and 2, the cabin 17 is provided with a steering wheel 51 for manual steering, a seat 50 for passengers, and the like. As a result, a boarding-type driving unit that allows the tractor 1 to be operated by the passenger is formed inside the cabin 17.
With reference to FIG. 3, the operation unit has an accelerator lever 53 that enables the maintenance of the rotation speed of the electric motor 13 at the set rotation speed, and enables the speed of the electric motor 13 to be increased from the set rotation speed. Accelerator pedal 56, clutch pedal 54 that enables intermittent operation of the main clutch 14, main shift lever 57 that enables shift operation of the main transmission 20, and reverser that enables forward / backward switching operation of the forward / backward switching device 21. The lever 52, the auxiliary transmission lever 61 that enables the shift operation of the auxiliary transmission 22, the PTO shift lever 58 that enables the shift operation of the PTO transmission 28, and the left and right brakes 30 can be switched to the braking state. The left and right brake pedals 55, etc. are included.

As shown in FIG. 4, the tractor 1 operates a fully hydraulic power steering unit 40 that steers the left and right front wheels 11, an electrohydraulic control type auto brake unit 41 that operates the left and right brakes 30, and a PTO clutch 27. Electronically controlled PTO valve unit 42, electro-hydraulic control type elevating drive unit 43 that elevates and drives the rotary tiller device 3, electro-hydraulic control type rolling unit 44 that swings and drives the rotary tiller device 3 in the roll direction, and a tractor. A vehicle state detection device 45 including various sensors and switches provided in 1 and an in-vehicle control unit 46 having various control units are provided.
The power steering unit 40 may be of an electric type having an electric motor for steering.

The vehicle state detection device 45 is a general term for various sensors and switches provided in each part of the tractor 1. The vehicle state detection device 45 is provided with an accelerator sensor S1 for detecting the amount of operation of the accelerator lever 53 and the accelerator pedal 56 from the idling position, a rotation sensor S2 for detecting the number of rotations of the electric motor 13, and an operation amount of the main speed change lever 57. The speed change sensor S3 to detect, the vehicle speed sensor S4 to detect the vehicle speed of the tractor 1 (an example of the vehicle speed detection unit), the reverser sensor S5 to detect the operating position of the reverser lever 52, and the steering angle sensor S6 to detect the steering angle of the front wheels 11 ( An example of a turning start detection unit), a height sensor S7 that detects the height position of the rotary tiller 3, and a vertical swing angle of the rear cover 3A (see FIG. 1) provided in the rotary tiller 3 so as to swing up and down. Various sensors such as a cover sensor S8 for detecting the above and an inclination sensor S9 for detecting the roll angle of the tractor 1 are included. The vehicle state detection device 45 includes a PTO switch Sw1 that commands the engagement and disengagement of the PTO clutch 27, a lift switch Sw2 that commands the raising and lowering of the rotary tiller 3 (an example of a work start detection unit), and a switching that commands switching of the traveling drive mode. Various switches such as switch Sw3 are included.

The height sensor S7 detects the vertical swing angle of the left and right lift arms included in the elevating drive unit 43 as the height position of the rotary tiller 3. The cover sensor S8 includes a grounding sensor for detecting the grounding of the rotary tilling device 3 and a grounding sensor for detecting the grounding of the rotary tilling device 3 because the rear cover 3A of the rotary tilling device 3 swings up and down according to the grounding of the rotary tilling device 3 and the working depth. It functions as a working depth sensor that detects the working depth of the device 3.
By the way, when the work machine connected to the rear part of the tractor 1 is a traction type work machine such as a plow, a cultivator, or a subsoiler, for example, a traction load that changes according to the work depth of the work machine is detected. If a strain gauge type draft sensor is provided at the base of the three-point link mechanism 2 to which a traction load is applied, the draft sensor can be used as a grounding sensor for detecting the grounding of the working machine and the working depth of the working machine. It can function as a working depth sensor to detect.

As shown in FIGS. 4 and 5, the in-vehicle control unit 46 includes a fuel cell control unit 46A that controls the fuel cell system 8, an electric motor control unit 46B that controls the electric motor 13, and the vehicle speed and front / rear of the tractor 1. Display and notification to the transmission unit control unit 46C that controls advance switching, the steering control unit 46D that controls steering, the work equipment control unit 46E that controls work equipment such as the rotary tiller 3, and the liquid crystal monitor 37. A non-volatile vehicle that stores the display control unit 46F for control, the automatic driving control unit 46G for controlling automatic driving, and the target route for automatic driving generated according to the driving area divided in the field. A storage unit 46H, etc. are included. Each of the control units 46A to 46G is constructed by an electronic control unit in which a microcontroller or the like is integrated, various control programs, or the like. The control units 46A to 46G are connected to each other so as to be able to communicate with each other via a CAN (Control Area Area Network).
For mutual communication between the control units 46A to 46G, a communication standard other than CAN or a next-generation communication standard such as an in-vehicle Ethernet or CAN-FD (CAN with FLexible Data rate) may be adopted.

When the accelerator lever 53 is operated, the electric motor control unit 46B idles the rotation speed of the electric motor 13 based on the detection information from the accelerator sensor S1 and the detection information from the rotation sensor S2. The rotation speed maintenance control of the electric motor 13 for maintaining the rotation speed according to the operation amount from the position is executed. When the accelerator pedal 56 is operated and the operation amount from the idling position of the accelerator pedal 56 exceeds the operation amount from the idling position of the accelerator lever 53, the electric motor control unit 46B detects detection information from the accelerator sensor S1. And based on the detection information from the rotation sensor S2, the rotation speed change control of the electric motor 13 for changing the rotation speed of the electric motor 13 to the rotation speed according to the operation amount from the idling position of the accelerator pedal 56 is executed.

When the main speed change lever 57 is operated, the speed change unit control unit 46C controls the operation of the main speed change device 20 based on the detection information from the speed change sensor S3 and the detection information from the vehicle speed sensor S4. The vehicle speed control for changing the vehicle speed of the tractor 1 to a speed corresponding to the operation position of the main speed change lever 57 is executed.
When the changeover switch Sw3 is operated, the speed change unit control unit 46C sets the traveling drive mode of the tractor 1 to the two-wheel drive mode, the four-wheel drive mode, the front wheel double speed mode, and the auto brake mode based on the operation of the changeover switch Sw3. Switch to.

In the state where the two-wheel drive mode is selected, the speed change unit control unit 46C switches the transmission switching device 26 to the transmission cutoff state to switch the drive state of the tractor 1 to the left and right front wheels 11 by blocking the transmission. It switches to a two-wheel drive state in which only the rear wheels 12 are driven.

In the state where the four-wheel drive mode is selected, the transmission unit control unit 46C switches the transmission switching device 26 to the constant speed drive state, so that the drive state of the tractor 1 is transmitted to the left and right front wheels 11 and the left and right front wheels. It switches to a four-wheel drive state in which the 11 and the left and right rear wheels 12 are driven at a constant speed.

In the state where the front wheel double speed mode is selected, the transmission unit control unit 46C sets the transmission switching device 26 to the constant speed transmission state and the front wheel double speed transmission state based on the detection information from the steering angle sensor S6 while setting the four-wheel drive state. Executes the front wheel double speed control function that switches to. The front wheel double speed control function determines that the tractor 1 has started turning when the steering angle of the front wheels 11 reaches the threshold value from less than the threshold value, and changes the transmission switching device 26 from the constant speed transmission state to the front wheel double speed transmission state. The front wheel double speed processing for switching, and when the steering angle of the front wheel 11 reaches from the threshold value or more to less than the threshold value, it is determined that the tractor 1 has finished turning, and the transmission switching device 26 is changed from the front wheel double speed transmission state to the constant speed transmission state. Includes front wheel constant velocity processing to switch.

In the state where the auto brake mode is selected, the speed change unit control unit 46C controls the operation of the auto brake unit 41 based on the detection information from the steering angle sensor S6 to release the left and right brakes 30 and turn inside. Executes the auto brake control function to switch to the braking state. The autobrake control function determines that the tractor 1 has started turning when the steering angle of the front wheels 11 reaches the threshold from less than the threshold, and also determines the steering direction of the front wheels 11 from the increasing / decreasing direction of the steering angle at that time. It is determined that the tractor 1 has finished turning when the turning inner braking process for switching the turning inner brake 30 from the braking release state to the braking state and when the steering angle of the front wheels 11 reaches from the threshold value to less than the threshold value. Then, the braking release process for switching the brake 30 in the braking state (inside the turning) to the braking release state is included.

The steering control unit 46D has a plurality of turning modes such as a two-wheel drive turning mode in which only the rear wheels 12 are rotationally driven to turn as in the two-wheel drive state, and front and rear wheels 11 and 12 as in the four-wheel drive state. A four-wheel drive turning mode in which the front wheels are rotationally driven to turn at a high speed, and a front wheel double-speed turning mode in which the front wheels 11 are rotationally driven to turn at a higher speed than the rear wheels 12 as in the front wheel double-speed transmission state (an example of the front wheel speed-up turning mode) ), Etc. Then, the steering control unit 46D performs a turning mode determination process for determining a turning mode to be executed when the vehicle body turns from these plurality of turning modes. Specifically, when the steering angle of the front wheels 11 detected by the steering angle sensor S6 is less than the set steering angle, turning is performed in the two-wheel drive turning mode or the four-wheel drive turning mode. When the steering angle of the front wheels 11 detected by the steering angle sensor S6 becomes equal to or greater than the set steering angle, turning is performed in the front wheel double speed turning mode in response to the operation of the changeover switch Sw3 by the passenger.
The steerth control unit 46D controls the operation of the power steering unit 40 to steer the left and right front wheels 11 in response to a steering command transmitted from the automatic travel control unit 46G, which will be described later, and the front wheels 11 When the steering angle reaches the threshold value, automatic braking turning control that controls the operation of the auto brake unit 41 to operate the brake 30 inside the turning is executed.

When the PTO switch Sw1 is operated to the on position, the work equipment control unit 46E controls the operation of the PTO valve unit 42 to switch the PTO clutch 27 from the transmission cutoff state to the transmission state. When the PTO switch Sw1 is operated to the off position, the work equipment control unit 46E controls the operation of the PTO valve unit 42 to switch the PTO clutch 27 from the transmission state to the transmission cutoff state.

The work equipment control unit 46E is based on the operation of the elevating switch Sw2, the detection information from the height sensor S7, the preset working height position, and the non-working height position for retracting, and the elevating drive unit 43. In a form in which the rotary tiller 3 is moved up and down between the working height position and the non-working height position by controlling the operation of the rotary tilling device 3, the posture of the rotary tilling device 3 is positioned at the working height position and the working posture and the non-working height. Performs elevating control to switch between the non-working posture located in. In the ascending / descending control, when the ascending command is commanded by the operation of the elevating switch Sw2, the ascending process for raising the rotary tilling device 3 from the working height to the non-working height and the descending command are commanded by operating the elevating switch Sw2. At that time, a lowering process of lowering the rotary tiller 3 from the non-working height position to the working height position is included. The input operation of the lowering command corresponds to the work start operation of changing the posture of the rotary tillage device 3 from the non-working posture to the working posture, and the input operation of the ascending command changes the posture of the rotary tilling device 3 from the working posture to the non-working posture. Corresponds to the work end operation to change to.

The work equipment control unit 46E determines that the steering angle of the front wheels 11 is less than the threshold value based on the detection information from the steering angle sensor S6, the detection information from the height sensor S7, and the preset non-working height position. When it is detected that the threshold has been reached, it is determined that the tractor 1 has started turning, and the operation of the elevating drive unit 43 is controlled to raise the rotary tiller 3 from the working height position to the non-working height position. It has a turning climb control function to make it.
The work equipment control unit 46E operates the reverser lever 52 to the reverse position based on the detection information from the reverser sensor S5, the detection information from the height sensor S7, and the preset non-working height position. When it is detected, it has a reverse ascent control function that controls the operation of the elevating drive unit 43 to raise the rotary tiller 3 from the working height position to the non-working height position.
The work equipment control unit 46E, for example, puts the PTO clutch 27 in a transmission cutoff state at a timing several seconds after the ascending command of the rotary cultivating device 3 is input or when the rotary cultivating device 3 rises to a predetermined height. In this form, it has a PTO clutch control function that controls the operation of the PTO valve unit 42 in conjunction with the elevating control by the work equipment control unit 46E to switch the PTO clutch 27 between the transmission cutoff state and the transmission state.
The work equipment control unit 46E controls the operation of the rolling unit 44 based on the detection information from the tilt sensor S9 and the preset control target posture to maintain the roll posture of the rotary tillage device 3 at the control target posture. It has an automatic rolling control function.

As shown in FIGS. 4 and 5, the tractor 1 is provided with a positioning unit (an example of a position measuring device) 70 for measuring the current position and the current azimuth of the tractor 1. The positioning unit 70 uses a GNSS (Global Navigation Satellite System), which is an example of a satellite positioning system (NSS: Navigation Satellite System), to measure the current position and current orientation of the tractor 1, and the satellite navigation device 71 and 3. It has an inertial measurement unit (IMU) 72 that measures the attitude and orientation of the tractor 1 with a shaft gyroscope and acceleration sensors in three directions. Positioning methods using GNSS include DGNSS (Differential GNSS: relative positioning method) and RTK-GNSS (Real Time Kinematic GNSS: interference positioning method). In this embodiment, RTK-GNSS suitable for positioning of a moving body is adopted. Therefore, as shown in FIG. 1, a reference station 6 that enables positioning by RTK-GNSS is installed at a known position around the field.

Each of the tractor 1 and the reference station 6 is provided with GNSS antennas 73, 6A and the like that receive radio waves transmitted from the positioning satellite 7 (see FIG. 1). As a result, the satellite navigation device 71 of the positioning unit 70 receives the positioning information obtained by the GNSS antenna 73 on the tractor side receiving the radio waves from the positioning satellite 7, and the GNSS antenna 6A on the reference station 6 side receives the radio waves from the positioning satellite 7. The current position and current orientation of the tractor 1 can be measured with high accuracy based on the positioning information obtained by receiving the radio wave. Further, the positioning unit 70 has the satellite navigation device 71 and the inertial measurement unit 72, so that the current position, the current azimuth, and the attitude angle (yaw angle, roll angle, pitch angle) of the tractor 1 can be measured with high accuracy. Can be done.
The positioning unit 70 on the tractor 1 side can directly perform wireless communication with the reference station 6 and obtain positioning information from the reference station 6.

In this tractor 1, the inertial measurement unit 72 of the positioning unit 70, the GNSS antenna 73, and the communication module 74 are included in the antenna unit 75 shown in FIG. The antenna unit 75 is arranged at the center of the upper left and right on the front side of the cabin 17. The positioning target position when measuring the current position of the tractor 1 is the axle center position of the rear wheel 12 obtained by converting from the mounting position of the GNSS antenna 73 in the tractor 1.

The mobile communication terminal 5 is a radio of each information including positioning information between an electronic control unit in which a microcontroller and the like are integrated, a terminal control unit 5B having various control programs, and a communication module 74 on the tractor side. It is equipped with a communication module 5C that enables communication.
Although not shown, the terminal control unit 5B includes a display control unit that controls display and notification of the display device 5A and the like, a target route generation unit that generates a target route for automatic driving (see FIG. 6), and a target route generation unit. It includes a non-volatile terminal storage unit that stores the target route and the like generated by the target route generation unit. As various information used to generate the target route, the terminal storage unit stores vehicle body information such as the turning radius and working width of the tractor 1, field information obtained from the positioning information described above, and the like.

The target route is stored in the terminal storage unit of the terminal control unit 5B in a state associated with vehicle body information, field information, and the like, and can be displayed on the display device 5A of the mobile communication terminal 5. The target route includes the target vehicle speed of the tractor 1 in each parallel route, the target vehicle speed of the tractor 1 in each direction change route, the front wheel steering angle in each parallel route, the front wheel steering angle in each direction change route, and the like. There is.

The terminal control unit 5B transmits field information, a target route, and the like stored in the terminal storage unit to the vehicle-mounted control unit 46 in response to a transmission request command from the vehicle-mounted control unit 46. The vehicle-mounted control unit 46 stores received field information, a target route, and the like in the vehicle-mounted storage unit 46H. Regarding the transmission of the target route, for example, even if the terminal control unit 5B transmits all of the target route from the terminal storage unit to the in-vehicle control unit 46 at once before the tractor 1 starts automatic traveling. Good. Further, the terminal control unit 5B divides the target route into a plurality of divided route information for each predetermined distance, and each time the traveling distance of the tractor 1 reaches the predetermined distance from the stage before the tractor 1 starts automatic traveling. A predetermined number of divided route information according to the traveling order of the tractor 1 may be sequentially transmitted from the terminal storage unit to the vehicle-mounted control unit 46.

The automatic driving control unit 46G is carried in a state in which a user such as a passenger or an administrator manually operates the tractor 1 to satisfy various automatic driving start conditions and the driving mode of the tractor 1 is switched to the automatic driving mode. When the display device 5A of the communication terminal 5 is operated to command the start of automatic driving, the positioning unit 70 automatically drives the tractor 1 according to the target route while acquiring the current position and current orientation of the tractor 1. Start driving control.

The automatic driving control by the automatic driving control unit 46G includes an electric motor automatic control process for transmitting a control command for automatic driving related to the electric motor 13 to the electric motor control unit 46B, and automatic driving for switching the vehicle speed and forward / backward movement of the tractor 1. Vehicle speed automatic control process that transmits the control command of the above to the speed change unit control unit 46C, steering automatic control process that transmits the control command for automatic driving related to steering to the steering control unit 46D, and automatic operation related to the work equipment such as the rotary tiller 3. It includes a work machine automatic control process for transmitting a running control command to the work machine control unit 46E.

In the electric motor automatic control process, the automatic traveling control unit 46G issues a rotation speed change command of the electric motor 13 for instructing a change of the rotation speed of the electric motor 13 based on a set rotation speed or the like included in the target path. It transmits to the electric motor control unit 46B. The electric motor control unit 46B automatically changes the rotation speed of the electric motor 13 in response to various control commands related to the electric motor 13 transmitted from the automatic travel control unit 46G, such as automatic change control of the rotation speed of the electric motor 13. Execute.

In the vehicle speed automatic control process, the automatic driving control unit 46G gives a shift operation command for instructing the shift operation of the main transmission 20 based on the target vehicle speed included in the target path, and the tractor 1 included in the target path. A forward / backward switching command for instructing the forward / backward switching operation of the forward / backward switching device 21 based on the traveling direction or the like is transmitted to the speed change unit control unit 46C. The speed change unit control unit 46C automatically controls the operation of the main speed changer 20 in response to various control commands related to the main speed changer 20 and the forward / backward changeover device 21 transmitted from the automatic travel control unit 46G. , And automatic forward / backward switching control that automatically controls the operation of the forward / backward switching device 21. The vehicle speed control includes, for example, an automatic deceleration stop process for decelerating and controlling the main transmission 20 to stop the traveling of the tractor 1 when the target vehicle speed included in the target route is zero speed. ..

In the automatic steering control process, the automatic driving control unit 46G transmits a steering command for instructing the steering of the left and right front wheels 11 based on the front wheel steering angle and the like included in the target path to the steering control unit 46D.
The steering control unit 46D controls the operation of the power steering unit 40 to steer the left and right front wheels 11 in response to the steering command transmitted from the automatic travel control unit 46G, and the steering angle of the front wheels 11 is adjusted. When the threshold value is reached, the operation of the auto-brake unit 41 is controlled to operate the brake 30 inside the turn, and the automatic braking turn control is executed.

The automatic traveling control unit 46G is included in the work start command for instructing the switching to the work posture of the rotary tillage device 3 based on the work start point included in the target route and the target route in the work machine automatic control process. A work stop command for instructing the switching of the rotary tillage device 3 to the non-working posture based on the work stop point, etc. is transmitted to the work machine control unit 46E.
The work equipment control unit 46E controls the operation of the PTO valve unit 42 and the elevating drive unit 43 in response to various control commands regarding the rotary tillage device 3 transmitted from the automatic traveling control unit 46G, and controls the rotary tillage device 3 to operate. Automatic work start control that lowers to the work height position and operates, automatic work stop control that stops the rotary tillage device 3 and raises it to the non-work height position, and the like are executed.

That is, the power steering unit 40, the auto brake unit 41, the PTO valve unit 42, the elevating drive unit 43, the rolling unit 44, the vehicle state detection device 45, the in-vehicle control unit 46, the positioning unit 70, the communication module 74, and the like are appropriate. By operating the tractor 1, the tractor 1 can be automatically driven with high accuracy according to the target route, and the tilling work by the rotary tilling device 3 can be properly performed.

Based on the flow shown in FIG. 6, the air supply control executed by the air supply control unit 46A1 will be described below.
The air supply control unit 46A1 is configured to execute air supply control for controlling the amount of air supplied to the fuel cell 8A by the air supply unit 8B of the fuel cell system 8.
That is, in this air supply control, although details will be described later, a load increase determination process (step # 1, FIG. 5) in which a load increase determination unit 46A3 predicts a rapid increase in the power load of the fuel cell 8A is expected. ~ (See FIG. 7) is performed. Then, when the determination process (step # 1) determines that the load is not in the load increase state but in the normal load state, the normal supply control (step # 2) is executed, and the determination process (step # 1) executes the load. If it is determined that the state is increasing, a predetermined rapid increase supply control (step # 3) is executed.

In the normal supply control (step # 2), the target air supply amount Ao becomes the required air supply amount AL (x) required to generate electric power corresponding to the electric power load x required by the fuel cell 8A. It is determined. On the other hand, in the rapid increase supply control (step # 3), the target air supply amount Ao is equal to the required air supply amount AL (x) required to generate electric power corresponding to the power load x required by the fuel cell 8A. Is also decided to be large. For example, the target air supply amount Ao is determined by multiplying the required air supply amount AL (x) by a coefficient R larger than 1, or the maximum air supply amount within the supplyable range of the air supply unit 8B. It can be determined to be Amax.
With such a configuration, it is possible to predict the fuel cell 8A, which is likely to have a rapid increase in power load, and increase the air supply amount in advance.

Next, the details of the determination process of whether or not the load is increased will be described.
The load increase determination unit 46A3 is configured to execute a determination process as shown in FIGS. 7 and 8 to determine whether or not a load increase state in which a rapid increase in the power load of the fuel cell 8A is predicted is expected. ing.

In the turning determination process shown in FIG. 7, it is determined whether or not the load is increased based on the detection result of the steering angle sensor S6. That is, the state in which the steering angle of the front wheels 11 detected by the steering angle sensor S6 is equal to or greater than the predetermined set steering angle (yes in step # 11) is a load increase state in which a rapid increase in the power load of the fuel cell 8A is predicted. It is determined that there is (step # 15). On the other hand, the state in which the steering angle of the front wheels 11 detected by the steering angle sensor S6 is less than the set steering angle (No in step # 21) is determined to be a normal load state other than the load increase state (step). # 12). Here, the set steering angle, which is a threshold value for determining whether or not the load is increased, is a threshold value for determining whether or not to perform turning in a turning mode such as the above-mentioned front wheel double speed turning mode. It is set to be slightly smaller than the set steering angle. That is, it is configured to predict that the load will increase immediately before switching to such a turning mode.

Further, in this turning determination process, it is determined whether or not the vehicle speed s of the tractor 1 detected by the vehicle speed sensor S4 is equal to or less than the predetermined set vehicle speed so (step # 14). Then, when the vehicle speed s of the tractor 1 is equal to or less than the set vehicle speed so (yes in step # 14), the rotational load of the electric motor 13 does not suddenly increase even if the turning start operation is performed. , The determination that the load is in the increased state is prohibited, and it is determined that the load is in the normal load state (step # 12).
In the present embodiment, when the vehicle speed of the tractor 1 is equal to or less than the predetermined set vehicle speed so, the determination that the load is increasing is prohibited, but such processing is appropriately modified or omitted. be able to.

Further, in this turning determination process, when it is once determined that the load is in the increased state (step # 15), the increase rate of the electric power load of the fuel cell 8A is maintained at less than the predetermined set rate, and the fuel cell 8A The elapsed time t in a state where the power load is stable is measured, and it is determined whether or not the elapsed time t exceeds a predetermined set elapsed time to (step # 16). Then, even if the turning start operation is not detected until the elapsed time t exceeds the set elapsed time to (no in step # 16), in other words, until the power load of the fuel cell 8A becomes stable. , The release of the determination of the load increase state is prohibited, and the determination of the load increase state (step # 15) is maintained. When the elapsed time t exceeds the set elapsed time to (yes in step # 16), it is determined that the fuel cell 8A is in a normal load state, assuming that the power load is stable (step # 12).
In the present embodiment, when it is determined that the load is increasing, it is prohibited to cancel the determination that the load is increasing until the power load of the fuel cell 8A becomes stable. , Such processing can be appropriately modified or omitted.

Then, when it is determined by the turning determination process as described above that the load is increasing, the air supply control unit 46A1 executes the above-mentioned rapid increase supply control (step # 3 in FIG. 6) to supply the target air. By setting the amount to be larger than the required air supply amount, the air supply amount to the fuel cell 8A becomes larger than when it is determined that the fuel cell 8A is in the normal load state. Therefore, for the fuel cell 8A, which is likely to have a rapid increase in power load due to turning, it is possible to predict it and increase the air supply amount in advance.

Further, in this turning determination process, when the load increase state is determined by the detection of the turning start operation by the steering angle sensor S6 (step # 15), the air supply control unit 46A1 causes the steering control unit 46D. The target air supply amount setting process for setting the target air supply amount according to the determined turning mode is executed (step # 13).
For example, the target air supply amount when turning in the four-wheel drive turning mode in which the increase rate of the electric power load is relatively larger than that in the two-wheel drive turning mode is set to be larger than when turning in the two-wheel drive turning mode. Further, the target air supply amount when turning in the front wheel double speed turning mode in which the increase rate of the electric power load is relatively larger than that in the four-wheel drive turning mode is set to be larger than when turning in the four-wheel drive turning mode. Further, in each of these turning modes, the target air supply amount when the auto brake mode is selected, which has a relatively large increase rate of the power load than when the auto brake mode is deselected, is larger than when the auto brake mode is deselected. Set. Therefore, even if the increase width of the electric power load varies depending on the turning mode to be executed, it is possible to supply the fuel cell 8A in advance with an appropriate amount of air to be supplied.
It should be noted that this turning determination process is also executed for the turning start operation detected during the above-mentioned automatic driving.

In the work equipment determination process shown in FIG. 8, it is determined whether or not the load is in the increase state based on the detection result of the elevating switch Sw2 that commands the elevating and lowering of the rotary tillage device 3. That is, the power of the fuel cell 8A is in a state in which the work start operation is performed by the elevating switch Sw2 and the posture of the rotary tiller 3 is changed from the non-working posture to the working posture by the work machine control unit 46E (yes in step # 21). It is determined that the load is in an increased state in which a rapid increase in load is expected (step # 24).

Further, in this work machine determination process, when the load increase state is determined by the detection of the work start operation by the elevating switch Sw2 (step # 24), the work mounted on the vehicle body by the air supply control unit 46A1. The target air supply amount setting process for setting the target air supply amount according to the work content of the machine (in this embodiment, the rotary tillage device 3 is mounted) is executed (step # 23).
For example, the target air supply amount when a work machine with a large load is installed is set to be larger than that when a work machine with a light load is installed. Therefore, even if the amount of increase in the power load varies depending on the work content of the work machine actually mounted on the vehicle body, it is possible to supply the fuel cell 8A with an appropriate amount of air in advance. it can.
The work content of the work machine is information that affects the power load consumed by the work machine, such as the type of the work machine, the type and state of work by the work machine, and the like. The information can be acquired from a work machine mounted on the vehicle body by communication or the like, or by an input operation to the display device 5A of the mobile communication terminal 5 or the liquid crystal monitor 37 of the driving unit.

Further, in this target air supply amount setting process (step # 23), the operating state of the PTO clutch 27, the presence / absence of automatic work stop control for stopping the rotary tillage device 3 and raising it to the non-working height position, and the rotary tillage device 3 The target air supply amount can also be set according to various setting conditions such as the descending speed of the tractor 1 and the vehicle speed of the tractor 1. For example, when the PTO clutch 27 is in the transmission state, when the automatic work stop control is performed, when the descending speed of the rotary tiller 3 is fast, when the vehicle speed of the tractor 1 is fast, the target air is higher than when it is not. The supply amount can be set large. Therefore, even when various settings related to the operating state of the rotary tillage device 3 are various, it is possible to supply the fuel cell 8A in advance with an appropriate amount of air to be supplied.

In this work equipment determination process, once it is determined that the load is increasing (step # 24), the work end operation is performed by the elevating switch Sw2, and the work equipment control unit 46E works on the posture of the rotary tiller 3. When the posture is changed to the non-working posture (yes in step # 25), the elapsed time t since the work end operation is performed is measured, and whether or not the elapsed time t exceeds the predetermined set elapsed time to. Is determined (step # 26). Then, until the elapsed time t exceeds the set elapsed time to (no in step # 26), in other words, until the rotary tillage device 3 is completely stopped and the power load of the fuel cell 8A becomes stable. Even when the rotary tillage device 3 is in the non-working posture, the release of the determination that the load is in the increased state is prohibited, and the determination that the load is in the increased state (step # 24) is maintained. Further, when the elapsed time t exceeds the set elapsed time to (yes in step # 26), it is determined that the fuel cell 8A is in a normal load state, assuming that the power load is stable (step # 22).
In the present embodiment, when it is determined that the load is increasing, it is prohibited to cancel the determination that the load is increasing until the power load of the fuel cell 8A becomes stable. , Such processing can be appropriately modified or omitted.

Then, when it is determined by the work equipment determination process as described above that the load is increasing, the air supply control unit 46A1 executes the above-mentioned rapid increase supply control (step # 3 in FIG. 6) to execute the target air. By setting the supply amount to be larger than the required air supply amount, the air supply amount to the fuel cell 8A becomes larger than when it is determined that the fuel cell 8A is in the normal load state. Therefore, for the fuel cell 8A in which the electric power load is likely to increase rapidly due to the work by the rotary tillage device 3, it is possible to predict it and increase the air supply amount in advance.

Further, as the determination process of whether or not the load is increased, it is possible to execute a determination process different from the turning determination process and the work machine determination process.
For example, when a large increase in the amount of operation from the idling position by the accelerator lever 53 and the accelerator pedal 56 is detected, or when the operation of switching the auxiliary transmission 22 from the low speed state to the high speed state by the auxiliary transmission lever 61 is detected. As described above, when various switches and sensors related to the vehicle speed change to a state in which the vehicle speed increases immediately afterwards, it can be determined that the load increase state is expected to increase the power load of the fuel cell 8A.

Further, even when the switching operation by the auxiliary shift lever 61 is detected, if the vehicle speed is low or the stopped state is maintained, the determination that the load is increased can be canceled.

Further, when the automatic driving control unit 46G executes the vehicle speed automatic control process so as to maintain the vehicle speed at the target vehicle speed, the deviation width of the actual vehicle speed detected by the vehicle speed sensor S4 with respect to the target vehicle speed is monitored, and the deviation width thereof is monitored. When the deviation width is larger than the permissible value, the fuel cell 8A is automatically accelerated thereafter, so that it can be determined that the load increase state is expected to increase the power load of the fuel cell 8A.

[Another Embodiment]
Another embodiment of the present invention will be described.
It should be noted that the configurations of the different embodiments described below are not limited to being applied individually, but can also be applied in combination with the configurations of other other embodiments.

(1) The configuration of the work vehicle 1 can be changed in various ways.
For example, the work vehicle 1 may be configured as a semi-crawler specification including left and right crawlers instead of the left and right rear wheels 12.
For example, the work vehicle 1 may be configured to have a full crawler specification in which left and right crawlers are provided instead of the left and right front wheels 11 and the left and right rear wheels 12.
For example, the work vehicle 1 may be configured with rear wheel steering specifications in which the left and right rear wheels 12 function as steering wheels.
For example, the work vehicle 1 may be configured such that the work machine 3 is vertically connected to the front portion thereof.
For example, the work vehicle 1 may be configured so that only manual traveling or automatic traveling is possible.

For example, when the work vehicle 1 is configured as a full crawler traveling type in which the left and right crawlers are driven to travel, as a plurality of turning modes, a slow turning mode in which the steering-side crawler is decelerated to turn the vehicle body. It is configured to have a brake turning mode in which the crawler on the steering side is stopped to turn the vehicle body, and a spin turning mode in which the crawler on the steering side is reversed to turn the vehicle body. .. Even in this case, the air supply control unit 46A1 sets the target air supply amount when turning in the slow turning mode or the brake turning mode in which the power load increase rate is relatively small, for example, in the spin turning in which the power load increase rate is relatively large. The target air supply amount when the load increase determination unit 46A3 determines that the load is in an increased state is set according to the turning mode determined by the steering control unit 46D, such as setting it smaller than when turning in the mode. can do.

(2) Regarding the turning start detection unit, a typical alternative embodiment other than the steering angle sensor S6 is as follows.
For example, the turning start detection unit may be a rotation sensor that detects the start of turning of the vehicle body from the rotation operation amount of the steering wheel 51.
For example, as a turning start detection unit, a positioning unit 70 that measures the current position and current azimuth of the work vehicle 1 using a satellite positioning system is diverted, and the amount of change in the current position and the amount of change in the current azimuth of the vehicle body are used. It may be configured to detect the start of turning.
For example, the inertial measurement unit 72 that measures the posture and orientation of the tractor 1 is diverted as the turning start detection unit, and the turning start of the vehicle body is detected from the yaw angle of the vehicle body detected by the inertial measurement unit 72. It may be configured.
For example, when the work vehicle 1 is configured to have full crawler specifications including left and right crawlers, the turning start detection unit uses a rotation sensor or the like that detects each drive speed of the left and right crawlers to detect the left and right crawlers. It may be configured to detect the start of turning of the vehicle body from the speed difference.
For example, the turning start detection unit may be configured to detect the turning start of the vehicle body from the centrifugal force applied to the vehicle body during the turning movement of the vehicle body.

(3) Regarding the work start detection unit, a typical alternative embodiment other than the elevating switch Sw2 is as follows.
For example, the work start detection unit may be a height sensor that detects from the height position of the work machine (rotary tillage device 3).
For example, as a work start detection unit, a positioning unit 70 that measures the current position and current azimuth of the work vehicle 1 using a satellite positioning system is diverted, and the amount of change in the current position and the amount of change in the current azimuth of the vehicle body are used. The entry of the work area may be detected as the start of work.
Further, as the turning start detection unit, the positioning unit 70 that measures the current position and the current azimuth of the work vehicle 1 by using the satellite positioning system is diverted, and the change amount of the current position and the change amount of the current azimuth of the vehicle body are used. The approach from the work area to the surrounding headland may be detected as a turning start operation.

1 Tractor (working vehicle)
3 Rotary tiller (working machine)
8A Fuel cell 8B Air supply section (oxidizer gas supply section)
13 Electric motor (driving electric motor, working machine electric motor)
46A1 Air supply control unit (oxidizer gas supply control unit)
46A3 Load increase determination unit 46B Electric motor control unit 46E Work equipment control unit Ao Target air supply amount S1 Accelerator sensor S4 Vehicle speed sensor (vehicle speed detection unit)
S6 Rudder angle sensor (turn start detector)
Sw2 lift switch (work start detector)
s Vehicle speed s1 Set vehicle speed t Elapsed time to Set elapsed time x Power load

Claims (7)

A fuel cell that generates electricity through an electrochemical reaction between a fuel gas and an oxidant gas,
An electric motor for traveling that generates a traveling force of a vehicle body on which a work machine can be mounted by the generated power of the fuel cell.
An oxidant gas supply unit that supplies the oxidant gas to the fuel cell,
A work vehicle including an oxidant gas supply control unit that controls the oxidant gas supply unit so that the oxidant gas supply amount to the fuel cell becomes a target oxidant gas supply amount.
A turning start detection unit that detects a turning start operation for turning the vehicle body,
A load increase determining unit for determining whether or not an increase in the power load of the fuel cell is predicted based on the detection result of the turning start detecting unit is provided.
When the target oxidant gas supply amount when the oxidant gas supply control unit determines that the load increase determination unit is in the load increase state is determined by the load increase determination unit to not be in the load increase state. Work vehicle set larger than. A vehicle speed detection unit that detects the vehicle speed of the vehicle body is provided.
The target oxidant gas supply amount when the oxidant gas supply control unit determines that the load increase determination unit is in the load increase state is set according to the vehicle speed of the vehicle body detected by the vehicle speed detection unit. The work vehicle according to claim 1 to be set. It is equipped with a steering control unit that determines the turning mode to be executed when the vehicle body turns from a plurality of turning modes.
The target oxidant gas supply amount when the oxidant gas supply control unit determines that the load increase determination unit is in the load increase state is set according to the turning mode determined by the steering control unit. The work vehicle according to claim 1 or 2. It is configured as a wheel running type that runs by driving the left and right front wheels and the left and right rear wheels.
As the plurality of turning modes, a two-wheel drive turning mode in which transmission to the left and right front wheels is blocked and only the left and right rear wheels are driven to turn the vehicle body, and the left and right front wheels and the left and right rear wheels A four-wheel drive turning mode in which the vehicle body is turned at a constant speed, and the left and right front wheels and the left and right rear wheels so that the peripheral speeds of the left and right front wheels are faster than the peripheral speeds of the left and right rear wheels. The work vehicle according to claim 3, further comprising a front wheel speed-up turning mode in which the wheels are driven to turn the vehicle body, and an auto-brake mode in which the rear wheels inside the turning are braked to turn the vehicle body. It is configured as a crawler running type that runs by driving the left and right crawlers.
The plurality of turning modes include a slow turning mode in which the steering-side roller is decelerated to turn the vehicle body, and a brake turning mode in which the steering-side roller is stopped to turn the vehicle body. The work vehicle according to claim 3, further comprising a spin turning mode in which the roller on the opposite side is reversed to turn the vehicle body. The turning start detection unit is a steering angle sensor that detects the steering angle.
The method according to any one of claims 1 to 5, wherein the load increase determination unit determines that the load increase state is obtained when the steering angle detected by the steering angle sensor is equal to or greater than the set steering angle. Work vehicle. It is equipped with an automatic driving control unit that automatically travels the vehicle body along a preset target route based on the current position of the vehicle body measured using a satellite positioning system.
The work vehicle according to any one of claims 1 to 6, wherein the turning start detecting unit detects a turning start operation during automatic traveling by the automatic traveling control unit.

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