Work vehicles

Abstract

This technology provides an improved convenience for work vehicles that can utilize multiple driving modes. [Solution] An exemplary work vehicle is a work vehicle that can switch between multiple driving modes and multiple gear shift states, and is equipped with a display device that displays a setting screen for setting the driving modes. The driving modes can be set separately for each gear shift state using the setting screen.

Description

Technical Field

[0003]

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

Background Art

[0002] Conventionally, a tractor capable of switching a traveling drive mode (traveling method) between a rear-wheel two-wheel drive state and a front-and-rear-wheel four-wheel drive state is known (see, for example, Patent Document 1). In Patent Document 1, the switching between the rear-wheel two-wheel drive state and the front-and-rear-wheel four-wheel drive state is performed using a two-wheel / four-wheel drive changeover lever disposed on the upper part of the fender.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, as traveling drive modes in a work vehicle, in addition to a two-wheel drive mode in which the rear wheels are driven and a four-wheel drive mode in which the front and rear wheels are driven, for example, a double speed mode in which the front wheels rotate at twice the speed of the rear wheels, an auto brake mode in which the rotational speed of the inner side of the rear wheels is suppressed during turning, and a plurality of other types of traveling drive modes are known. Also, the available traveling drive modes may change depending on the usage state of the sub-shift. For this reason, if the configuration is such that the setting and switching of the traveling drive mode in the work vehicle are performed using a physical switch such as a lever or a button, the labor of operation may increase, or the correspondence between the operation and the actual operation of the work vehicle may become difficult to understand.

[0005] An object of the present invention is to provide a technique capable of improving the convenience of a work vehicle that can utilize a plurality of traveling drive modes.

Means for Solving the Problems

[0006] An exemplary work vehicle of the present invention is a work vehicle that can switch between a plurality of driving modes and a plurality of gear shift states, and is equipped with a display device that displays a setting screen for setting the driving modes, and the driving modes can be set separately for each gear shift state using the setting screen. [Effects of the Invention]

[0007] According to an exemplary example of the present invention, the convenience of a work vehicle that can utilize multiple driving modes can be improved. [Brief explanation of the drawing]

[0008] [Figure 1] Side view showing the general configuration of the work vehicle. [Figure 2] Diagram illustrating the control system of a work vehicle. [Figure 3] Block diagram showing the functions of the touch panel control unit included in the touch panel. [Figure 4] Schematic diagram showing the configuration of the meter panel. [Figure 5] This diagram shows an example of a screen for setting the driving mode using a touch panel. [Figure 6] This diagram shows another example of a driving mode setting screen using a touch panel. [Figure 7] This diagram shows a portion of the mode transition table used when the sub-transmission is set to the working stage. [Figure 8] This diagram shows a portion of the mode transition table used when the sub-transmission setting is set to the driving gear. [Figure 9] A flowchart illustrating the process of automatically switching between driving modes. [Figure 10] A schematic diagram showing the configuration around the steering wheel located in the driver's compartment. [Figure 11] This diagram shows another portion of the mode transition table used when the sub-transmission setting is in the working stage. [Figure 12] This diagram shows another portion of the mode transition table used when the sub-transmission setting is set to a driving gear. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and descriptions will not be repeated unless they require further explanation.

[0010] Furthermore, in this specification, directions are defined as follows: First, the direction in which a work vehicle travels in a straight line is defined as the front-rear direction, with the steering wheel being on the front side relative to the driver's seat of the work vehicle. Also, the right side is defined as the right and the left side as viewed from the perspective of an operator sitting in the driver's seat facing forward, and the left side is defined as the left-right direction perpendicular to the front-rear direction. In addition, the direction perpendicular to both the front-rear and left-right directions is defined as the up-down direction, with gravity being the direction of gravity being down and the opposite direction being up. The above directions are merely descriptive names and are not intended to limit actual positional relationships or directions.

[0011] <1. Overview of work vehicles> Figure 1 is a side view showing a schematic configuration of a work vehicle 1 according to an embodiment of the present invention. More specifically, Figure 1 is a left side view. As shown in Figure 1, the work vehicle 1 comprises a vehicle body 11 and a work machine 12.

[0012] The vehicle body 11 constitutes the main part of the work vehicle 1 and is capable of traveling in the work area 200. The work implement 12 is equipped to the work vehicle 1 by being attached to the vehicle body 11 or otherwise. The work vehicle 1 performs work travel using the work implement 12. The work vehicle 1 performs work travel in the work area 200. In this embodiment, the work area 200 is, for example, a field. That is, the work vehicle 1 is a field work vehicle that performs ground work in the field 200.

[0013] Furthermore, the work vehicle 1 may travel on public roads or other roads to move between locations other than the work area 200. In other words, the places on which the work vehicle 1 travels are not limited to the work area 200.

[0014] In addition, in the present embodiment, the working machine 12 is attached to the rear part of the vehicle body portion 11. The work vehicle 1 is a tractor that pulls the working machine 12 by the vehicle body portion 11. However, the working machine 12 may be configured to be attached to the front part of the vehicle body portion 11. That is, the work vehicle of the present invention may be configured to include a working machine at the front part of the vehicle body portion. The work vehicle of the present invention may be a work vehicle for agricultural work other than a tractor, or a work vehicle for civil engineering work, construction work, or the like.

[0015] The vehicle body portion 11 includes a base portion 13 and a pair of left and right traveling portions 14 that support the base portion 13 and are arranged at intervals in the left - right direction. Each of the left and right traveling portions 14 includes a front wheel 14a and a rear wheel 14b. That is, the front wheel 14a includes a left - hand front wheel 14a and a right - hand front wheel 14a. Also, the rear wheel 14b includes a left - hand rear wheel 14b and a right - hand rear wheel 14b.

[0016] The front wheels 14a and the rear wheels 14b are provided so as to be able to transmit power from a power source 15 arranged in front of the base portion 13. When power is transmitted from the power source 15 to the front wheels 14a or the rear wheels 14b, the vehicle body portion 11 can travel on a field 200 or the like. In the present embodiment, the power source 15 is an engine, but it is not limited to this, and the power source may be a motor or the like.

[0017] The base portion 13 is provided with a driving portion 16 on which an operator (user) rides. The driving portion 16 is provided with a driver's seat 16a on which the operator sits, a steering wheel 16b arranged in front of the driver's seat 16a and enabling the operator to steer the work vehicle 1, and a plurality of operation tools (not shown in FIG. 1) enabling the operator to perform various operations.

[0018] The multiple control devices include a main gear lever and a sub-gear lever. The main gear lever is used to change the travel speed of the work vehicle 1 steplessly (to change it arbitrarily). The sub-gear lever is used to specify one of two speeds, for example (low speed and high speed). The operator specifies a rough speed with the sub-gear lever, and then uses the main gear lever to specify a finer speed.

[0019] The work implement 12 is connected to the rear of the base unit 13 via a coupling mechanism 17. In this embodiment, the work implement 12 is connected to the base unit 13 so as to be able to move up and down. A PTO shaft 18 is located at the rear of the base unit 13 to output power generated by the power source 15 to the work implement 12. Power from the power source 15 is transmitted to the PTO shaft 18 via a transmission 19. Note that the power source that drives the work implement 12 may be provided separately from the power source 15 that drives the vehicle body 11. This separately provided power source may be a motor or the like.

[0020] In this embodiment, the implement 12 is a rotary tiller. The ground work performed by the work vehicle 1 is tilling. However, the implement 12 is not limited to a rotary tiller; it may also be a plow, harvester, harrow, puddling machine, pesticide sprayer, fertilizer spreader, etc. Furthermore, the work vehicle 1 may be equipped with interchangeable implements 12 of multiple types.

[0021] Figure 2 is a diagram illustrating the control system of a work vehicle 1 according to an embodiment of the present invention. In Figure 2, only the components necessary to explain the features of the work vehicle 1 according to the embodiment of the present invention are shown, and descriptions of other general components are omitted. As shown in Figure 2, the work vehicle 1 is equipped with a control device 2.

[0022] The control device 2 is a computer device comprising, for example, an arithmetic unit, an input / output unit (neither of which are shown), and a storage unit 21. The arithmetic unit is an integrated circuit such as a processor or microprocessor. The storage unit 21 is a main memory device such as ROM (Read Only Memory) and RAM (Random Access Memory). The storage unit 21 may further include an auxiliary storage device such as an HDD (Hard Disk Drive) or SSD (Solid State Drive). Various programs and data are stored in the storage unit 21. The arithmetic unit reads various programs from the storage unit 21 and performs arithmetic processing according to the programs.

[0023] In this embodiment, the control device 2 can be operated as various functional units through the cooperation of the above-described hardware and software. As shown in Figure 2, the various functional units include a travel drive mode control unit 22, a travel control unit 23, a work equipment control unit 24, and a display control unit 25. Details of each functional unit 22 to 25 will be described later.

[0024] In this embodiment, each of the functional units 22-25 of the control device 2 is realized by software, that is, by the arithmetic unit executing arithmetic processing according to a program. However, this is an example, and the functions of the functional units may be realized by other methods. At least a portion of each of the functional units 22-25 may be realized using, for example, an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). In other words, at least a portion of each of the functional units 22-25 may be realized by hardware using a dedicated IC or the like. Furthermore, at least a portion of each of the functional units 22-25 may be realized by a combination of software and hardware. Also, each of the functional units 22-25 is a conceptual component. The function performed by one component may be distributed among multiple components. Furthermore, the functions of multiple components may be integrated into one component.

[0025] Furthermore, the control device 2 may consist of a single piece of hardware, or it may consist of multiple pieces of hardware that can communicate with each other. For example, the work vehicle 1 may be equipped with a remote control device (not shown) that enables remote operation by an operator located away from the vehicle body 11. In such a case, the control device 2 may be configured to be located only in the vehicle body 11, or it may be configured to be located separately on the vehicle body 11 side and the remote control device side. The remote control device is a device that can communicate with the vehicle body 11, and may be, for example, a tablet terminal, smartphone, laptop computer, or remote control.

[0026] Furthermore, the control device 2 may be configured to communicate with the server device via a network such as the Internet. In such a case, some of the functions of the control device 2 may be implemented by the server device. Also, some of the information stored in the storage unit 21 may be stored in the server device.

[0027] As shown in Figure 2, the work vehicle 1 includes, in addition to the control device 2, elements 3 to 5 that are directly or indirectly connected to the control device 2. These elements 3 to 5 and the control device 2 may be connected, for example, by wire or wireless. Alternatively, these elements 3 to 5 may be connected by wire or wireless to a device that can communicate with the control device 2 (such as the remote control device or server device mentioned above), and indirectly connected to the control device 2 via the communication device.

[0028] Sensor 3 detects information related to the work vehicle 1 and outputs the detected information to the control device 2. In detail, multiple types of sensors 3 are mounted on the work vehicle 1. Each of the multiple types of sensors 3 outputs the detected information to the control device 2. Sensor 3 is mounted, for example, on the vehicle body 11 or the work machine 12. In some cases, sensor 3 may be installed on a device that can be used at a location away from the vehicle body 11 (such as the remote control device mentioned above). The multiple types of sensors 3 include, for example, a speed sensor that detects the speed of the work vehicle 1, a steering angle sensor that detects the steering angle using the steering wheel 16b of the work vehicle 1, a GNSS (Global Navigation Satellite System) sensor that detects the position of the work vehicle 1, and lever position sensors that detect the position of the main and sub-transmission levers.

[0029] The operation unit 4 enables the operator to issue commands to the control device 2. In this embodiment, the operation unit 4 includes a plurality of operating devices. The operation unit 4 is provided, for example, on the vehicle body 11. However, if the work vehicle 1 is configured to include a remote control device, at least some of the operating devices constituting the operation unit 4 may be included in the remote control device. The operation unit 4 may be, for example, buttons, levers, dials, or touch panels.

[0030] As shown in Figure 2, in this embodiment, the operation unit 4 includes a touch panel TP. The touch panel TP is also included in the display unit 5 because it functions as both an input device and a display device. Details of the touch panel TP will be described later. Furthermore, in this embodiment, the operation unit 4 includes a travel mode selector switch 41. Details of the travel mode selector switch 41 will also be described later.

[0031] The display unit 5 displays information as appropriate in response to commands from the control device 2. In this embodiment, the display unit 5 includes a plurality of display devices. The display unit 5 is provided, for example, on the vehicle body 11. However, if the work vehicle 1 is configured to include a remote control device, at least some of the display devices constituting the display unit 5 may be included in the remote control device.

[0032] In this embodiment, the display unit 5 includes a meter panel 51 and a touch panel TP. The meter panel 51 is located in front of the steering wheel 16b of the driver's unit 16 (see Figure 10, described later) and displays various information related to the work vehicle 1. For example, the meter panel 51 displays speed information, fuel information, water temperature information, and driving mode (driving method) information.

[0033] The touch panel TP is positioned, for example, around the driver's seat 16a. The touch panel TP displays at least a settings screen for setting the driving mode of the work vehicle 1. The operator (user) can make settings related to the driving mode on the settings screen. Details regarding the setting of the driving mode will be described later. Preferably, in addition to setting the driving mode, the touch panel TP can also be used to set other functions of the work vehicle 1, such as settings related to automatic driving.

[0034] Figure 3 is a block diagram illustrating the functions of the touch panel control unit TPC provided by the touch panel TP. The touch panel control unit TPC is a computer device equipped with an arithmetic unit consisting of a processor and the like. The functions of the touch panel control unit TPC are realized by the processor executing arithmetic processing according to a program. As shown in Figure 3, the touch panel control unit TPC comprises a reception unit TP-1, a display processing unit TP-2, and a transmission unit TP-3 as its functional units.

[0035] The reception unit TP-1 receives touch operations from the operator on the touch panel TP. The display processing unit TP-2 performs display processing in response to the operator's touch operations and in response to instructions from the control device 2. The transmission unit TP-3 transmits the content of the instructions (instruction information) from the operator's touch operations to the control device 2.

[0036] Furthermore, the touch panel TP may be configured to be installed in the vehicle body 11, or it may be incorporated into a portable device that can be brought into or taken out of the vehicle body 11. The portable device may be, for example, the remote control device described above. In addition, the functions realized by the touch panel TP of this embodiment may be realized by a combination of input devices and display devices that are configured separately.

[0037] Returning to Figure 2, we will now explain the overview of the functions of the control device 2.

[0038] The driving mode control unit 22 performs control processing related to the driving mode (driving method). The work vehicle 1 in this embodiment is equipped to be switchable between multiple driving modes. The operator can set the driving mode using the driving change switch 41 or the touch panel TP. The driving mode control unit 22 decides whether or not to switch the current driving mode in response to the operator's instruction using the driving change switch 41 or the touch panel TP.

[0039] In the work vehicle 1 of this embodiment, the selectable driving modes include a two-wheel drive mode, a four-wheel drive mode, a double-speed mode, and a turning two-wheel drive mode. The driving mode of the work vehicle 1 is set to one of the following modes under the control of the driving mode control unit 22: two-wheel drive mode, four-wheel drive mode, double-speed mode, and turning two-wheel drive mode.

[0040] The 2WD mode is a driving mode in which the work vehicle 1 is driven using two wheels, the left and right rear wheels 14b. The 4WD mode is a driving mode in which the work vehicle 1 is driven using four wheels, the left and right front wheels 14a and the left and right rear wheels 14b. The double-speed mode is a driving mode in which the front wheels 14a rotate faster than the rear wheels 14b (rotating at approximately twice the speed) when turning. The turning 2WD mode is a driving mode in which the vehicle is driven using two wheels only when turning, and four wheels at all other times.

[0041] Furthermore, the work vehicle 1 of this embodiment is equipped with an auto brake that can be used in combination with each of the following modes: 2WD mode, 4WD mode, double-speed mode, and turning 2WD mode. When the auto brake is activated, the work vehicle 1 drives while applying the brake to the rear wheel 14b on the turning side when turning.

[0042] In this embodiment, the work vehicle 1 can be switched between multiple gear states by using a sub-gear lever (not shown). Multiple gear states may also be referred to as multiple sub-gear stages. Multiple gear states include a state set to a low-speed stage for low-speed driving and a state set to a high-speed stage for high-speed driving. The low-speed stage is a gear state (gear stage) used when performing work driving and is also called the work stage. The high-speed stage is a gear state (gear stage) used when driving on roads such as public roads and is also called the driving stage. Note that the number of multiple gear states (sub-gear stages) is not limited to two, but may be three or more. Further finer gear settings may be made within the low-speed stage and high-speed stage.

[0043] In the work vehicle 1 of this embodiment, the gear shift state selected by the sub-transmission lever influences the selection of the driving mode and the selection of whether to enable or disable the auto brake, taking safety into consideration. For this reason, the driving mode control unit 22 makes decisions regarding the switching of the driving mode, taking into account the gear shift state selected by the sub-transmission lever in addition to the operator's instructions using the driving change switch 41 or touch panel TP. Details of the setting and switching process of the driving mode will be described later. The gear shift state (gear step) selected by the sub-transmission lever can be determined from the information from the lever position sensor for the sub-transmission lever included in the sensor 3 described above.

[0044] The driving control unit 23 controls the driving system of the work vehicle 1 according to the driving mode determined by the driving mode control unit 22. When the driving mode is set to 2WD mode, the driving control unit 23 causes the work vehicle 1 to perform 2WD driving according to the input instructions such as speed and steering. When the driving mode is set to 4WD mode, the driving control unit 23 causes the work vehicle 1 to perform 4WD driving according to the input instructions such as speed and steering. When the driving mode is set to double speed mode, the driving control unit 23 causes the work vehicle 1 to perform 4WD driving according to the input instructions such as speed and steering, and when a turn is detected, causes it to perform double speed driving by rotating the front wheels 14a faster than the rear wheels 14b. When the driving mode is set to the turning 2WD mode, the driving control unit 23 causes the work vehicle 1 to perform 4-wheel drive driving in accordance with the input information such as speed and steering, and to perform 2-wheel drive driving when a turn is detected.

[0045] Furthermore, instruction information such as speed and steering may be obtained by the operator operating (manually operating) the control devices (steering wheel, levers, pedals, etc.) provided on the driver's unit 16. However, if the work vehicle 1 is equipped with an automatic driving function, instruction information such as speed and steering may be information calculated by the control device 2 using information obtained from the sensor 3. In addition, whether or not the work vehicle 1 is turning may be determined using steering angle information obtained from the steering angle sensor included in the sensor 3.

[0046] The work equipment control unit 24 controls the work system of the work vehicle 1 according to the input operation information related to the work equipment 12. This control of the work system includes, for example, lifting and lowering control of the work equipment 12 and switching control of power transmission to the work equipment 12 using the PTO power transmission unit. The operation information related to the work equipment 12 may be obtained by the operator operating (manually operating) the operating tools (levers, pedals, etc.) provided on the driver's unit 16. However, if the work vehicle 1 is equipped with an automatic driving function including automatic control of the work equipment 12, the information may be obtained by the control device 2 according to the information from the sensor 3.

[0047] The display control unit 25 controls the display unit 5 according to information obtained from the sensor 3 and other control units 22 to 24. Specifically, the display control unit 25 controls the display of the meter panel 51 and the touch panel TP. In this embodiment, the display control of the meter panel 51 by the display control unit 25 includes display control related to the driving mode. This will be briefly explained with reference to Figure 4.

[0048] Figure 4 is a schematic diagram showing the configuration of the meter panel 51. As shown in Figure 4, the meter panel 51 displays a speedometer 51a, a fuel meter 51b, and a water temperature meter 51c. The meter panel 51 also includes a driving mode display unit 51d that informs the operator of the currently set driving mode, and an auto brake display unit 51e.

[0049] The driving mode display unit 51d indicates the currently set driving mode by illuminating the corresponding character. For driving modes that are not currently set, the corresponding character will not be illuminated. For example, if the currently set driving mode is 4WD mode, the corresponding character "4WD" will be illuminated, while "Double Speed" and "Turning 2WD," which correspond to other driving modes, will not be illuminated. The operator can recognize the current driving mode from the illuminated state of the character.

[0050] In the example shown in Figure 4, the character corresponding to the double-speed mode is "double speed," and the character corresponding to the turning 2WD mode is "turning 2WD." Also, in the example shown in Figure 4, the character corresponding to the 2WD mode (for example, "2WD") is not available on the driving mode display unit 51d. Therefore, in detail, when the 2WD mode is set, no illuminated character is displayed on the driving mode display unit 51d. Even with this configuration, the operator can recognize that the current driving mode is 2WD mode because no illuminated character is displayed on the driving mode display unit 51d, so there is no particular problem. However, the driving mode display unit 51d may be configured so that the character "2WD," which corresponds to the 2WD mode, is illuminated when the 2WD mode is set.

[0051] The auto brake indicator unit 51e is equipped with the words "auto brake". When the auto brake is set, the words "auto brake" on the auto brake indicator unit 51e are illuminated, and when the auto brake is not set, the words "auto brake" are not illuminated. The operator can recognize whether the auto brake is enabled or disabled from the illumination status of the words "auto brake".

[0052] <2. Details related to driving modes> Next, we will describe in detail the matters related to the driving mode of the work vehicle 1 of this embodiment.

[0053] As can be seen from the above explanation, the multiple drive modes that can be switched (set) in the work vehicle 1 include a 2WD mode that drives the rear wheels 14b and a 4WD mode that drives both the front wheels 14a and the rear wheels 14b. Furthermore, the multiple drive modes also include a double-speed mode that rotates the front wheels 14a faster than the rear wheels 14b, and a turning 2WD mode that switches from 4WD mode to 2WD mode when turning.

[0054] The work vehicle 1 is equipped with a display device that shows a setting screen for setting the driving mode. In detail, this display device is the touch panel TP described above (see Figure 2). Note that if the display device that shows the setting screen for setting the driving mode is equipped with a separate input device connected to the display device, a touch operation input function is not required, and the display device does not need to be a touch panel.

[0055] In the work vehicle 1, the driving mode can be set separately for each gear shift state using a setting screen for setting the driving mode. With this configuration, even if the driving mode that can be set changes depending on the gear shift state, the procedure for setting the driving mode can be prevented from becoming complicated or difficult to understand. In other words, the operability for the operator (user) when setting the driving mode can be improved.

[0056] The shift state refers to the shift state that can be switched using the sub-shift lever. In the work vehicle 1, the switchable shift states include the first shift state and the second shift state. The first shift state is, in detail, the state in which the sub-shift is set to a low speed (working speed). The second shift state is, in detail, the state in which the sub-shift is set to a high speed (traveling speed). In the work vehicle 1, the travel drive mode for the first shift state and the travel drive mode for the second shift state can be set separately using the touch panel TP.

[0057] Figure 5 shows an example of the driving mode setting screen using the touch panel TP. Figure 6 shows another example of the driving mode setting screen using the touch panel TP. Specifically, Figure 5 is the driving mode setting screen when the gear shift state is the first gear shift state, and Figure 6 is the driving mode setting screen when the gear shift state is the second gear shift state.

[0058] In other words, in this embodiment, the touch panel TP (display device) switches and displays a setting screen for setting the driving mode for each gear shift state. Specifically, the setting screen for setting the driving mode includes a first setting screen SS1 for the first gear shift state (see Figure 5) and a second setting screen SS2 for the second gear shift state (see Figure 6). While it is possible to configure the system so that the driving mode for each gear shift state can be set on a single setting screen, switching the setting screen for setting the driving mode for each gear shift state, as in this embodiment, makes the setting items displayed on the setting screen easier to see and understand.

[0059] As can be seen by comparing Figure 5 and Figure 6, the configurable items differ between the first setting screen SS1 and the second setting screen SS2. If the configurable driving mode changes according to the gear shift state, the operator may become confused about the setting of the driving mode. However, with the configuration of this embodiment, the operator can easily understand that the configurable items change depending on the gear shift state. Furthermore, because the setting screen is displayed separately for each gear shift state, the complexity of the setting items on each setting screen can be suppressed, and the operator's operation of setting the driving mode can be made easier.

[0060] As shown in Figure 5, the first setting screen SS1 has a title display area R1, a gear shift status selection area R2, a driving mode selection area R3, an auto brake selection area R4, and a screen switching icon display area R5. When describing the first setting screen SS1, the terms up, down, left, and right will be used based on the first setting screen SS1 shown in Figure 5. The directions of up, down, left, and right used in describing the first setting screen SS1 do not necessarily have to match the directions of up, down, left, and right defined earlier for the overall description of the work vehicle 1.

[0061] The title display area R1 is provided as an area to display a predetermined title so that the operator can easily grasp the content of the selected screen. In the example shown in Figure 5, the title display area R1 is a horizontal rectangle and is located at the top edge of the rectangular settings screen. As an example, the title displayed in the title display area R1 of the first settings screen SS1 is "Driving Switching". In addition, in the example shown in Figure 5, an icon corresponding to the title name is also displayed so that the content of the selected screen can be easily grasped at a glance.

[0062] The gear shift state selection area R2 is provided as an area that enables switching between setting screens provided for each gear shift state. More specifically, the gear shift state selection area R22 has a work gear selection area R2a and a travel gear selection area R2b. The work gear selection area R2a is a selection area for displaying the screen for setting the travel drive mode when the sub-transmission is set to work gear (i.e., the first gear shift state) (i.e., the first setting screen SS1). The travel gear selection area R2b is a selection area for displaying the screen for setting the travel drive mode when the sub-transmission is set to travel gear (i.e., the second gear shift state) (i.e., the second setting screen SS2). Both the work gear selection area R2a and the travel gear selection area R2b are horizontally elongated rectangles and are provided below the title display area R1. The two areas R2a and R2b are arranged horizontally, with the work gear selection area R2a on the left and the travel gear selection area R2b on the right.

[0063] When the work gear selection area R2a is touched, the first setting screen SS1 shown in Figure 5 is displayed. When the travel gear selection area R2b is touched, the second setting screen SS2 shown in Figure 6 is displayed. The gear state selection area R2 displays the gear state selection area that is not currently selected in the setting screen in gray and reduces the display area compared to the selected area, making it easier to understand which gear state is currently selected in the setting screen. In the screen shown in Figure 5, the gear state selection area that is not currently selected in the setting screen is the travel gear selection area R2b. The travel gear selection area R2b is displayed in gray and has a smaller display area compared to the work gear selection area R2a. Note that at least one of the gray display and the reduction in the display area does not need to be provided as a function in the setting screen.

[0064] The driving mode selection area R3 is an area for the operator to select the driving mode they wish to use. The driving mode selected by the operator in this area becomes the driving mode set by the operator. The driving modes that can be set on the first setting screen SS1 include 2WD mode, 4WD mode, double speed mode, and turning 2WD mode. Therefore, the driving mode selection area R3 has a 2WD mode selection area R3a, a 4WD mode selection area R3b, a double speed mode selection area R3c, and a turning 2WD mode selection area R3d.

[0065] The driving mode selection area R3 is located below the gear shift state selection area R2. Each mode selection area R3a, R3b, R3c, and R3d is a horizontally elongated rectangle, arranged in two columns horizontally and two columns vertically, in the center of the first setting screen SS1. More specifically, the four mode selection areas R3a, R3b, R3c, and R3d are arranged in the center of the first setting screen SS1, with the 2WD mode selection area R3a on the upper left, the 4WD mode selection area R3b on the upper right, the double speed mode selection area R3c on the lower left, and the turning 2WD mode selection area R3d on the lower right.

[0066] Each mode selection area R3a, R3b, R3c, and R3d displays characters and icons to identify the driving mode, as well as marks to indicate the selected state. In the example shown in Figure 5, the characters used to identify the driving mode are "2WD", "4WD", "Double Speed ​​+ 4WD", and "Turning 2WD". "2WD" means 2WD mode. "4WD" means 4WD mode. "Double Speed ​​+ 4WD" means double speed mode. "Turning 2WD" means turning 2WD mode. In addition, in the example shown in Figure 5, a filled circle ("●") and an open circle ("〇") are used to indicate the selected state. A filled circle indicates that the corresponding mode selection area is selected. An open circle indicates that the corresponding mode selection area is not selected.

[0067] Of the four mode selection areas R3a, R3b, R3c, and R3d, if, for example, the 2WD mode selection area R3a is touched, the 2WD mode is selected as the driving mode. When the 2WD mode is selected, the mark indicating the selection status in the 2WD mode selection area R3a becomes a filled circle. In this case, the 4WD mode selection area R3b, the double-speed mode selection area R3c, and the turning 2WD mode selection area R3d are not selected, so the marks indicating their selection status become white circles. Figure 5 illustrates these states.

[0068] While a detailed explanation is omitted, if the 4WD mode selection area R3b is touched among the four mode selection areas R3a, R3b, R3c, and R3d, 4WD mode will be selected as the driving mode. Also, if the double speed mode selection area R3c is touched among the four mode selection areas R3a, R3b, R3c, and R3d, double speed mode will be selected as the driving mode. If the cornering 2WD mode selection area R3d is touched among the four mode selection areas R3a, R3b, R3c, and R3d, cornering 2WD mode will be selected as the driving mode.

[0069] The auto-brake selection area R4 is an area that allows the operator to select whether to enable or disable the auto-brake. The auto-brake selection area R4 is located below the driving mode selection area R3. In the example shown in Figure 5, the auto-brake selection area R4 consists of a rectangular area R4a extending horizontally and a circular area R4b located within the rectangular area R4a. By moving the circular area R4b left or right within the rectangular area R4a using touch operation, the auto-brake can be switched between enabled and disabled. In the example shown in Figure 5, the auto-brake is enabled when the circular area R4b is positioned to the right of the rectangular area R4a. That is, Figure 5 shows the screen state when the operator selects to enable the auto-brake. On the other hand, the auto-brake is disabled when the circular area R4b is positioned to the left of the rectangular area R4a.

[0070] In the example shown in Figure 5, when the circular area R4b is positioned to enable the auto brake, the rectangular area R4a is filled in. Conversely, when the circular area R4b is positioned to disable the auto brake, the rectangular area R4a is not filled in. This configuration allows the operator to instantly determine whether the auto brake is enabled or disabled.

[0071] Furthermore, in this embodiment, the auto brake can be enabled or disabled for each driving mode that can be set on the first setting screen SS1. That is, the operator can enable or disable the auto brake for each of the 2WD mode, 4WD mode, double speed mode, and turning 2WD mode. When the sub-transmission setting is in the working stage, the operator can make mode settings related to a total of eight driving modes. To make these settings, the operator only needs to touch the driving mode selection area R3 and the auto brake selection area R4 once each. In other words, with the configuration of this embodiment, despite the large number of types of mode settings related to driving modes, the mode settings can be made with simple operation.

[0072] The screen switching icon display area R5 is provided to allow easy switching from the driving mode switching screen (driving mode switching screen) to other screens. The screen switching icon display area R5 is located below the auto brake selection area R4 and at the lower end of the first setting screen SS1. The screen switching icon display area R5 contains multiple areas arranged horizontally, each displaying an icon, for example, representing the home screen. When an area with an icon is touched, the touch panel TP screen switches to the screen corresponding to the touched icon.

[0073] As shown in Figure 6, the second setting screen SS2 has a title display area R1, a gear shift status selection area R2, a driving mode selection area R3, a screen switching icon display area R5, an automatic speed setting area R6, and a warning area R7. The configuration of the title display area R1, the gear shift status selection area R2, and the screen switching icon display area R5 is the same as in the first setting screen SS1 described above, so their explanations will be omitted. In describing the second setting screen SS2, the top, bottom, left, and right text will be used based on the second setting screen SS2 shown in Figure 6. In this respect, it is the same as in the description of the first setting screen SS1.

[0074] The driving mode selection area R3 is, as in the case of the first setting screen SS1, an area for the operator to select the driving mode they wish to use. However, in this embodiment, for reasons such as ensuring safety, the double-speed mode and the turning 2WD mode cannot be used when the auxiliary transmission is set to a driving gear. Also, for the same reason, the auto brake cannot be used when the auxiliary transmission is set to a driving gear. For this reason, the driving modes that can be set on the second setting screen SS2 include the 2WD mode and the 4WD mode. The driving modes that can be set on the second setting screen SS2 do not include the double-speed mode and the turning 2WD mode.

[0075] In detail, the driving mode selection area R3 in the second setting screen SS2 includes only the 2WD mode selection area R3a and the 4WD mode selection area R3b, and does not include the double-speed mode selection area R3c or the cornering 2WD mode selection area R3d. Also, the auto brake selection area R4 is not provided in the second setting screen SS2. In other words, when the sub-transmission setting is for driving, the operator can only set either the 2WD mode or the 4WD mode for the driving mode setting.

[0076] When comparing the first setting screen SS1 and the second setting screen SS2 shown in Figures 5 and 6, a difference is observed in the position of the 4WD mode selection area R3b relative to the 2WD mode selection area R3a. In the second setting screen SS2, the 2WD mode selection area R3a and the 4WD mode selection area R3b are positioned vertically, slightly to the left of the center of the screen. However, this is an example, and the position of the 4WD mode selection area R3b relative to the 2WD mode selection area R3a may be the same in both the first setting screen SS1 and the second setting screen SS2.

[0077] The automatic switching speed setting area R6 is a region that allows the operator to set the speed at which the driving mode is automatically switched from 4WD mode to 2WD mode when the auxiliary transmission is set to a driving gear. In the work vehicle 1 of this embodiment, in order to reduce deterioration of fuel consumption and tire wear, a configuration is adopted in which the driving mode is automatically changed from 4WD mode to 2WD mode when the driving speed of the work vehicle 1 reaches a certain value, but only when the auxiliary transmission is set to a driving gear. The automatic switching speed setting area R6 is provided so that the operator can set this certain value.

[0078] In other words, in the work vehicle 1, when driving in the second gear state, an automatic switch from 4WD mode to 2WD mode occurs when the driving speed reaches a preset speed threshold. In this embodiment, an automatic switching speed setting area R6 is provided on the second setting screen SS2. Therefore, the speed threshold setting can be changed on the second setting screen SS2. With this configuration, it is possible to switch from 4WD mode to 2WD mode at a timing that suits the operator's needs according to the operating environment and conditions. This improves the ease of use that the operator perceives with the work vehicle 1.

[0079] The automatic speed setting area R6 is located to the right of the 4WD mode selection area R3b. The automatic speed setting area R6 is a horizontally elongated rectangle. The automatic speed setting area R6 displays an explanation of the speed setting, the set speed, and buttons (software buttons) for setting the speed. The buttons for setting the speed include a set speed increase button represented by "+" and a set speed decrease button represented by "-". Touching the set speed increase button increases the set speed. Touching the set speed decrease button decreases the set speed. In the example shown in Figure 6, the set speed is "15 km / h". From this state, touching the set speed increase button allows the set speed to be set to a value greater than 15 km / h. Conversely, touching the set speed decrease button allows the set speed to be set to a value less than 15 km / h. The percentage of increase or decrease in the set speed using the buttons can be, for example, in units of 1 km / h.

[0080] For example, in poor road conditions such as muddy or snowy roads, it is possible to use the automatic switching speed setting range R6 to set the automatic switching speed (the same as the speed threshold mentioned above) higher. By setting it this way, it becomes possible to drive in 4WD mode when traction is needed at the start of driving, and then automatically switch to 2WD mode once driving has stabilized and the speed has reached a medium or higher speed.

[0081] Furthermore, in the second settings screen SS2, it may be possible to set the system to disable automatic switching from 4WD mode to 2WD mode. Some operators may want to always drive in 4WD mode when the sub-transmission is set to the driving gear. By allowing the system to disable automatic switching, the needs of a wider range of operators can be met.

[0082] The setting to disable automatic switching can be configured, for example, by providing an automatic switching disable button (software button) on the second setting screen SS2. Alternatively, the automatic switching may be disabled when the automatic switching speed (speed threshold) set using the automatic switching speed setting area R6 is set to a predetermined value. The predetermined value may be, for example, the upper limit of the speed that can be set in the automatic switching speed setting area R6. This configuration eliminates the need to add an automatic switching disable button and prevents the display of the second setting screen SS2 from becoming overly complex. When automatic switching is disabled, it is preferable to display text or otherwise indicate this so that the operator can recognize it.

[0083] The warning area R7 is an area where text is displayed to alert the operator regarding settings made using the second setting screen SS2. In the example shown in Figure 6, the warning area R7 is configured to display text informing the operator that an automatic switch from 4WD mode to 2WD mode will occur. The text displayed in the warning area R7 may always be the same, but it may also be configured to change according to the operator's settings made using the second setting screen SS2. For example, if the above automatic switching is disabled, text informing the operator of this may be displayed in the warning area R7.

[0084] Figure 7 shows a portion of the mode transition table TA1 used when the auxiliary transmission is set to the work stage. Figure 8 shows a portion of the mode transition table TA2 used when the auxiliary transmission is set to the driving stage. In Figures 7 and 8, the symbol "AB" is an abbreviation for auto brake. Furthermore, below, the mode transition table TA1 used when the auxiliary transmission is set to the work stage may be referred to as the first mode transition table TA1. Similarly, the mode transition table TA2 used when the auxiliary transmission is set to the driving stage may be referred to as the second mode transition table TA2.

[0085] Mode transition tables TA1 and TA2 are tables that the control device 2 (driving mode control unit 22) refers to when settings related to the driving mode, including the setting of the auto brake, are made, and are stored in the storage unit 21 (see Figure 2). When settings related to the driving mode are made, the driving mode control unit 22 refers to mode transition tables TA1 and TA2 to make the settings related to the driving mode.

[0086] As shown in Figures 7 and 8, the items included in the mode transition tables TA1 and TA2 are "mode number," "mode name," "function," and "operation during switching reception."

[0087] The "Mode Number" field stores an identification number assigned to distinguish between multiple configurable modes. The "Mode Number" field acts as the primary key for mode transition tables TA1 and TA2, and a data record is generated for each mode number. This data record stores information corresponding to each mode number, including the "Mode Name," "Function," and "Operation during Switching Reception."

[0088] The "Mode Name" field stores the name of each mode. The "Function" field stores the function performed in each mode. The "Function" field is further subdivided into "4WD," "Double Speed," "Turning 2WD," and "Auto Brake (AB)." "ON" is stored when the subdivided function is performed, and "OFF" is stored when the subdivided function is not performed. The "Operation upon Switching Reception" field stores the switching operation that the driving mode control unit 22 should perform when the driving mode is set using the touch panel TP. The "Operation upon Switching Reception" field is further subdivided and stored for each setting selection switch (such as the 2WD mode selection area R3a shown in Figures 5 and 6), the number of types of which differs depending on the setting state of the sub-transmission, but this will be explained later.

[0089] First, we will explain the mode switching operation using the first mode transition table TA1 (see Figure 7), which is used when the sub-transmission is set to the work stage. In the first mode transition table TA1, eight numbers from "1" to "8" are stored for the mode number. The mode names assigned to each mode number are "2WD", "4WD", "Double Speed", "Turning 2WD", "2WD + Auto Brake", "4WD + Auto Brake", "Double Speed ​​+ Auto Brake", and "Turning 2WD + Auto Brake". Furthermore, the item "Operation upon Switching Reception" is subdivided into "2WD Switch", "4WD Switch", "Double Speed ​​+ 4WD Switch", "Turning 2WD Switch", and "Auto Brake Switch", and the switching operation that the driving mode control unit 22 should perform when the respective switch is operated is stored for each subdivided switch.

[0090] The "2WD switch" corresponds to the 2WD mode selection area R3a (see Figure 5) above. The "4WD switch" corresponds to the 4WD mode selection area R3b (see Figure 5) above. The "double speed + 4WD switch" corresponds to the double speed mode selection area R3c (see Figure 5) above. The "turning 2WD switch" corresponds to the turning 2WD mode selection area R3d (see Figure 5) above. The "auto brake switch" corresponds to the auto brake selection area R4 (see Figure 5) above.

[0091] Here, we assume that the setting of the sub-transmission is a work step. Then, suppose the operator performs a setting operation related to the driving mode using the first setting screen SS1. In this case, the driving mode control unit 22 makes a decision on switching modes related to the driving mode according to the first mode transition table TA1.

[0092] For example, if the current mode setting is Mode 1 (corresponding to mode number "1"; the same applies hereafter), and the operator operates the 2WD switch, the driving mode control unit 22 determines to maintain Mode 1 according to the first mode transition table TA1. Also, for example, if the current mode setting is Mode 1 and the operator operates the 4WD switch, the driving mode control unit 22 determines to switch from Mode 1 to Mode 2 according to the first mode transition table TA1. Furthermore, for example, if the current mode setting is Mode 1 and the operator operates the auto brake switch, the driving mode control unit 22 determines to switch from Mode 1 to Mode 5 according to the first mode transition table TA1. Note that all of the above examples are processes executed by referring to the row for mode number "1" in the first mode transition table TA1. While it is not necessary to explain all cases, in other cases as well, the driving mode control unit 22 makes mode switching decisions according to the first mode transition table TA1 in the manner described above.

[0093] Next, we will explain the mode switching operation using the second mode transition table TA2 (see Figure 8), which is used when the sub-transmission setting is set to the driving stage. In the second mode transition table TA2, two numbers, "1" and "2", are stored for the mode number. The mode names "2WD" and "4WD" are stored as assigned to each mode number. Furthermore, the item "Operation upon switching reception" is subdivided into "2WD switch" and "4WD switch", and the switching operation that the driving mode control unit 22 should perform when the subdivided switch is operated is stored for each switch.

[0094] Here, we assume that the setting for the sub-transmission is the driving gear. Then, suppose the operator performs a setting operation related to the driving mode using the second setting screen SS2. In this case, the driving mode control unit 22 makes a decision on switching modes related to the driving mode according to the second mode transition table TA2.

[0095] For example, if the current mode setting is Mode 1 and the operator operates the 2WD switch, the driving mode control unit 22 determines to maintain Mode 1 according to the second mode transition table TA2. Also, for example, if the current mode setting is Mode 1 and the operator operates the 4WD switch, the driving mode control unit 22 determines to switch from Mode 1 to Mode 2 according to the second mode transition table TA2. Also, for example, if the current mode setting is Mode 2 and the operator operates the 2WD switch, the driving mode control unit 22 determines to switch from Mode 2 to Mode 1 according to the second mode transition table TA2. Also, for example, if the current mode setting is Mode 2 and the operator operates the 4WD switch, the driving mode control unit 22 determines to maintain Mode 2 according to the second mode transition table TA2.

[0096] When the driving mode control unit 22 decides to change the driving mode, the displays on the driving mode display unit 51d and the auto brake display unit 51e (both shown in Figure 4) on the meter panel 51 are changed as appropriate under the control of the display control unit 25. The operator can quickly confirm the current mode setting related to the driving mode by checking the displays on the driving mode display unit 51d and the auto brake display unit 51e.

[0097] Furthermore, when the work vehicle 1 is started, the drive mode control unit 22 sets the mode according to the setting of the sub-transmission at the time of starting and the settings related to the drive mode that have already been set by setting screens SS1 and SS2.

[0098] Furthermore, even if the auxiliary transmission setting is changed midway through operation, the settings related to the driving mode in the setting screens SS1 and SS2 remain unchanged. The driving mode control unit 22 determines the mode to use according to the setting conditions set for each gear (gear state) when the auxiliary transmission setting is changed. However, the double speed mode, turning 2WD mode, and auto brake, which are available when the auxiliary transmission setting is a work gear, cannot be used when the auxiliary transmission setting is a driving gear. For this reason, if the setting is "2WD + auto brake" in the work gear, it will become "2WD" when switched to a driving gear. If the setting is "double speed", "turning 2WD", "4WD + auto brake", "double speed + auto brake", or "turning 2WD + auto brake" in the work gear, it will become "4WD" when switched to a driving gear.

[0099] Figure 9 is a flowchart illustrating the flow of the automatic switching process of the driving mode performed by the control device 2 (specifically, the driving mode control unit 22). Specifically, this automatic switching process refers to the automatic switching process from the 4WD mode to the 2WD mode. The process shown in Figure 9 is executed when the work vehicle 1 is started and the driving mode switching process is possible.

[0100] In step S1, the drive mode control unit 22 determines whether the sub-transmission is set to a driving gear and the drive mode is set to 4WD mode. If the sub-transmission is set to a driving gear and the drive mode is set to 4WD mode (Yes in step S1), the process proceeds to the next step S2. On the other hand, if the conditions that the sub-transmission is set to a driving gear and the drive mode is set to 4WD mode are not met (No in step S1), the process in step S1 is repeated.

[0101] In step S2, the driving mode control unit 22 determines whether the driving speed of the work vehicle 1 is equal to or greater than the speed threshold. The speed threshold corresponds to the automatic switching speed set in the automatic switching speed setting area R6 of the second setting screen SS2 (see Figure 6). If the driving speed is equal to or greater than the speed threshold (Yes in step S2), the process proceeds to the next step S3. If the driving speed is less than the speed threshold (No in step S2), the process proceeds to step S6.

[0102] In step S3, the drive mode control unit 22 changes the drive mode from 4WD mode to 2WD mode. Due to the action of the drive control unit 23 in response to this change, the work vehicle 1 operates in 2WD mode. Once the change to 2WD mode is made, the process proceeds to the next step S4.

[0103] In step S4, the driving mode control unit 22 determines whether the driving speed of the work vehicle 1 is less than a speed threshold. If the driving speed is less than a speed threshold (Yes in step S4), the process proceeds to the next step S5. If the driving speed is equal to or greater than the speed threshold (No in step S4), the process proceeds to step S6.

[0104] In step S5, the drive mode control unit 22 changes the drive mode from 2WD mode to 4WD mode. That is, the drive mode is returned to 4WD mode. Due to the operation of the drive control unit 23 in response to the change operation of the drive mode control unit 22, the work vehicle 1 performs 4WD driving. Once the change to 4WD mode is made, the process proceeds to the next step S6.

[0105] In step S6, the drive mode control unit 22 determines whether there is a reason to terminate the automatic switching process. Reasons for termination include, for example, when the sub-transmission setting is changed to the work stage by the operator, or when the drive mode setting is changed to 2WD mode by instruction from the operator. If there is a reason to terminate (Yes in step S6), the flow shown in Figure 9 is terminated. On the other hand, if there is no reason to terminate (No in step S6), the process proceeds to the next step S7.

[0106] In step S7, the driving mode control unit 22 determines whether the current driving mode is 4WD mode. If it is 4WD mode (Yes in step S7), the process returns to step S2. If it is not 4WD mode (No in step S7), the process returns to step S4.

[0107] Figure 10 is a schematic diagram showing the configuration around the steering wheel 16b provided in the driver's unit 16. As shown in Figure 10, a drive mode selector switch 41 is located below the steering wheel 16b. The drive mode selector switch 41 is a physical switch, specifically a button. The drive mode selector switch 41 is a switch that switches between drive modes.

[0108] In other words, in the work vehicle 1, the settings for multiple driving modes can be configured not only by the display device (touch panel TP in this embodiment) but also by a driving mode selector switch 41 provided around the driver's seat 16a. With this configuration, even when it is difficult to set the driving mode using the display device, for example, when attention is required in front of the work vehicle 1, the driving mode can be switched using the driving mode selector switch 41.

[0109] Referring to Figures 11 and 12, the operation of switching the driving mode using the driving mode selector switch 41 will be explained. Figure 11 shows another part of the mode transition table used when the sub-transmission is set to the working stage. Here, "showing another part" means showing a part that is different from the figure shown in Figure 7. Figure 12 shows another part of the mode transition table used when the sub-transmission is set to the driving stage. Here, "showing another part" means showing a part that is different from the figure shown in Figure 8.

[0110] As shown in Figure 11, the mode transition table (first mode transition table TA1) used when the sub-transmission setting is in the working stage includes, in addition to the items shown in Figure 7, "operation when the drive selector switch is pressed". The item "operation when the drive selector switch is pressed" is information included in the data record generated for each mode number. The item "operation when the drive selector switch is pressed" stores the switching operation that the drive mode control unit 22 should perform when the drive mode switching operation is performed using the drive selector switch 41.

[0111] When the sub-transmission is set to the working stage and the drive change switch 41 is pressed by the operator, the drive mode control unit 22 performs a drive mode switching operation according to the item "Operation when drive change switch is pressed" in the first mode transition table TA1.

[0112] Here, the setting for the sub-transmission is the work stage, and the current mode setting (corresponding to the setting on the first setting screen SS1) is Mode 1. In this case, each time the operator presses the drive selector switch 41, the drive mode control unit 22 switches according to the first mode transition table TA1, such as "Mode 2" → "Mode 3" → "Mode 7" → "Mode 4" → "Mode 1" → "Mode 2"... In detail, in "Mode 1", the "action when the drive selector switch is pressed" is "to Mode 2", so when the operator presses the drive selector switch 41, it switches to "Mode 2". In "Mode 2", which is switched from "Mode 1", the "action when the drive selector switch is pressed" is "to Mode 3", so when the operator presses the drive selector switch 41, it switches to "Mode 3". In "Mode 3", which is switched from "Mode 2", the "action when the drive selector switch is pressed" is "to Mode 7", so when the operator presses the drive selector switch 41, it switches to "Mode 7". In "Mode 7," which is switched from "Mode 3," the "action when the travel selector switch is pressed" is "to Mode 4," so when the operator presses the travel selector switch 41, it switches to "Mode 4." In "Mode 4," which is switched from "Mode 7," the "action when the travel selector switch is pressed" is "to Mode 1," so when the operator presses the travel selector switch 41, it switches to "Mode 1."

[0113] From the above, it can be seen that pressing the drive selection switch 41 five times returns the vehicle to its original mode. In other words, when using the drive selection switch 41, it may be necessary to press the switch up to four times to set the desired mode. If the number of switch operations required to set the desired mode becomes too high, the operator may find the operation cumbersome. Taking this into consideration, the setting of the auto brake using the drive selection switch 41 is configured to be possible only in double-speed mode. If the operator wishes to set the auto brake for other driving modes, they will need to perform a setting operation using the touch panel TP.

[0114] Furthermore, when initiating a mode setting switch operation using the driving switch 41, the operation may start from a mode that cannot be set using the driving switch 41, such as "2WD + auto brake," "4WD + auto brake," or "2WD cornering + auto brake." In this case, as shown in Figure 11, regardless of the mode setting, when the driving switch 41 is pressed, it will first switch to "Mode 2." Then, if the driving switch 41 is pressed again, each time the driving switch 41 is pressed, it will switch through "Mode 3" → "Mode 7" → "Mode 4" → "Mode 1" → "Mode 2"... In other words, it is not possible to return to the originally set "2WD + auto brake," "4WD + auto brake," or "2WD cornering + auto brake" by operating only the driving switch 41.

[0115] As shown in Figure 12, the mode transition table (second mode transition table TA2) used when the sub-transmission setting is set to the driving stage includes, in addition to the items shown in Figure 8, "operation when the driving selector switch is pressed". Since "operation when the driving selector switch is pressed" is the same as that of the first mode transition table TA1 described above, a detailed explanation is omitted.

[0116] When the sub-transmission is set to the driving stage and the driving selector switch 41 is pressed by the operator, the driving mode control unit 22 performs a driving mode switching operation according to the item "Operation when driving selector switch is pressed" in the second mode transition table TA2.

[0117] Here, let's assume that the sub-transmission setting is "driving gear" and the current mode setting (corresponding to the setting on the second setting screen SS2) is Mode 1. In this case, each time the operator presses the driving selector switch 41 once, the driving drive mode control unit 22 switches between "Mode 2" → "Mode 1" → "Mode 2"... according to the second mode transition table TA2. If the sub-transmission setting is "driving gear", it can be seen that pressing the driving selector switch 41 twice will return to the original mode.

[0118] As can be seen from the above explanation, mode settings related to the driving mode using the driving selector switch 41 have limitations compared to mode settings using the touch panel TP's setting screen. However, using the driving selector switch 41 has the advantage that the operator can switch mode settings while looking ahead. The operator can comfortably set the driving mode by deciding whether to use mode settings using the touch panel TP's setting screen or mode settings using the driving selector switch 41, depending on the situation.

[0119] <3. Things to keep in mind> Various technical features disclosed herein may be modified in various ways without departing from the spirit of the technical creation. Furthermore, the multiple embodiments, examples, and modifications shown herein may be combined as possible.

[0120] <4. Addendum> The embodiments, examples, and modifications described above are further disclosed below.

[0121] An exemplary work vehicle of the present invention is a work vehicle that can switch between multiple driving modes and multiple gear shift states, and is equipped with a display device that displays a setting screen for setting the driving modes, and the driving modes may be configured to be set separately for each gear shift state using the setting screen (first configuration).

[0122] In the work vehicle with the first configuration described above, the display device may be configured to switch and display the setting screen for each gear shift state (second configuration).

[0123] In the work vehicle with the second configuration described above, the gear shift state includes a first gear shift state and a second gear shift state, and the setting screen includes a first setting screen for the first gear shift state and a second setting screen for the second gear shift state, and the items that can be set on the first setting screen and the second setting screen are different (third configuration).

[0124] In the work vehicle with the third configuration described above, the plurality of driving modes may include a 2WD mode that drives the rear wheels and a 4WD mode that drives both the front and rear wheels (fourth configuration).

[0125] In the work vehicle of the fourth configuration described above, when the vehicle is traveling in the second gear shift state, it may be configured to automatically switch from the four-wheel drive mode to the two-wheel drive mode when the travel speed reaches a preset speed threshold (fifth configuration).

[0126] In the work vehicle of the fifth configuration described above, the configuration (sixth configuration) may be such that the speed threshold setting can be changed in the second setting screen.

[0127] In the work vehicle of the fifth or sixth configuration described above, the second setting screen may be configured to allow the prohibition of automatic switching (seventh configuration).

[0128] In the work vehicle of the seventh configuration described above, the automatic switching may be prohibited when the speed threshold is set to a predetermined value (the eighth configuration).

[0129] In a work vehicle having any of the above configurations 3 to 8, the drive mode that can be set on the first setting screen may include a 2WD mode that drives the rear wheels, a 4WD mode that drives the front and rear wheels, a double-speed mode that rotates the front wheels faster than the rear wheels, and a turning 2WD mode that switches from the 4WD mode to the 2WD mode when turning, and the drive mode that can be set on the second setting screen may include the 2WD mode and the 4WD mode (configuration 9).

[0130] In a work vehicle with any of the above configurations 3 to 9, the system may be configured such that the automatic brake can be switched between enabled and disabled for each driving mode that can be set on the first setting screen (configuration 10).

[0131] In a work vehicle with any of the above configurations 1 to 10, the settings for the multiple driving modes may also be configured to be set by a driving mode selector switch provided around the driver's seat, in addition to the display device (configuration 11). [Explanation of symbols]

[0132] 1. Work vehicles 14a... Front wheel 14b...Rear wheel 16a... Driver's seat 41...Train mode selector switch SS1...First settings screen SS2...Second settings screen TP... Touch panel (display device)

Claims

1. A work vehicle capable of switching between multiple driving modes and multiple gear shift states, The system includes a display device that shows a setting screen for setting the aforementioned driving mode, The aforementioned driving mode can be set separately for each gear change state using the setting screen, for a work vehicle.

2. The work vehicle according to claim 1, wherein the display device switches and displays the setting screen for each gear shift state.

3. The aforementioned gear shift state includes a first gear shift state and a second gear shift state. The aforementioned settings screen includes a first settings screen for the first gear shift state and a second settings screen for the second gear shift state. The work vehicle according to claim 2, wherein the items that can be set on the first setting screen and the second setting screen are different.

4. The work vehicle according to claim 3, wherein the plurality of driving modes include a two-wheel drive mode that drives the rear wheels and a four-wheel drive mode that drives the front and rear wheels.

5. The work vehicle according to claim 4, wherein when the vehicle is in the second gear shift state, it automatically switches from the four-wheel drive mode to the two-wheel drive mode when the driving speed reaches a preset speed threshold.

6. The work vehicle according to claim 5, wherein the speed threshold setting can be changed in the second setting screen.

7. The work vehicle according to claim 6, wherein the second setting screen is configured to allow the prohibition of the automatic switching.

8. The work vehicle according to claim 7, wherein the automatic switching prohibition is set when the speed threshold is set to a predetermined value.

9. The driving modes that can be set on the first setting screen include: A two-wheel drive mode that drives the rear wheels, A four-wheel drive mode that drives both the front and rear wheels, A double-speed mode that makes the front wheels rotate faster than the rear wheels, A turning 2WD mode that switches from the 4WD mode to the 2WD mode when turning, It includes, The work vehicle according to claim 3, wherein the driving mode that can be set on the second setting screen includes the two-wheel drive mode and the four-wheel drive mode.

10. The work vehicle according to claim 9, wherein the auto brake can be switched between enabled and disabled for each driving mode that can be set on the first setting screen.

11. The work vehicle according to any one of claims 1 to 10, wherein the settings of the plurality of driving modes can also be set by a driving mode change switch provided around the driver's seat, in addition to the display device.

Images