Work vehicles

Abstract

To permit a vehicle body to travel along a scheduled travel line even under the influence of positioning error (positioning accuracy) by a positioning device.SOLUTION: A work vehicle includes: a vehicle body; a coupling part; a steering handle; a positioning device that detects a vehicle body position; an automatic steering mechanism capable of automatically steering the vehicle body based on the vehicle body position detected by the positioning device and a scheduled travel line; a display device capable of displaying deviation between the vehicle body position detected by the positioning device and the scheduled travel line; and a correction switch for setting a correction amount. The automatic steering mechanism is capable of automatic steering based on deviation changed with the correction amount set by the correction switch, and when the deviation is not changed by the correction switch, the display device displays, as deviation, position deviation between the vehicle body position and the scheduled travel line and, upon change in the deviation by the correction switch, changes the position deviation in accordance with the correction amount set by the correction switch and displays the position deviation.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a work vehicle, for example, a tractor. [Background technology]

[0002] Conventionally, an agricultural machine is known from Patent Document 1. The agricultural machine of Patent Document 1 includes a traveling machine body that can freely switch between manual traveling by manual steering and automatic traveling by automatic steering along a set traveling line that is set parallel to a reference traveling line, and a changeover switch that can freely switch between manual traveling and automatic traveling. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-123803 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the agricultural machine of Patent Document 1, the position of the machine is detected using a GPS or the like to set a reference driving line, a set driving line, etc., so the reality is that it is not possible to reduce the influence of positioning by the GPS or the like on the steering, driving, etc. of the machine.

[0005] In view of the above problems, the present invention has an object to provide a work vehicle that can drive the vehicle body along a planned travel line even when affected by positioning errors (positioning accuracy) by a positioning device. [Means for solving the problem]

[0006] The technical means of the present invention for solving this technical problem is characterized by the following points.

[0007] The work vehicle comprises a vehicle body capable of travelling, a coupling section capable of coupling a work device that performs work to the vehicle body, a steering handle for steering the vehicle body by a rotational operation, a positioning device provided on the vehicle body and detecting the vehicle body position based on a signal from a positioning satellite, an automatic steering mechanism capable of automatically steering the vehicle body based on the vehicle body position detected by the positioning device and a planned travel line, a display device capable of displaying a deviation between the vehicle body position detected by the positioning device and the planned travel line, and a correction switch for setting a correction amount, wherein the automatic steering mechanism is capable of the automatic steering based on the deviation changed by the correction amount set by the correction switch, and the display device is Display a screen for changing the correction amount of the operation unit of the correction switch .

[0008] The work vehicle is equipped with a control device to which the correction switch is connected and which controls the automatic steering mechanism, and the control device sets the correction amount based on the number of times the correction switch is operated, and the correction amount per operation is the correction amount per one operation of the correction switch.

[0009] The control device changes the correction amount corresponding to one operation of the correction switch based on information displayed on the screen and input to a setting input unit that accepts input of a correction amount for each operation.

[0010] The correction switch is connected to a control device that controls the automatic steering mechanism, and the control device sets the correction amount based on the operation amount of the correction switch, and the correction amount per operation unit is the correction amount per specified operation amount of the correction switch.

[0011] The control device changes the correction amount per operation amount of the correction switch based on information displayed on the screen and input to a setting input section that accepts an input of a correction amount for each operation unit.

[0012] The display device includes: The above The starting point of the driving reference line used to set the planned driving line When is set, on the above screen First Icon Display End point of the driving reference line When is set, on the above screen Second Icon of Display.

[0013] The work vehicle includes the work implement connected to the coupling portion. Effect of the Invention

[0014] According to the present invention, even when steering or the like is performed using the vehicle body position detected by the positioning device, the influence of positioning errors by the positioning device can be reduced. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is a diagram showing the configuration and control block diagram of a tractor. [Diagram 2] FIG. 2 is an explanatory diagram for explaining automatic steering. [Figure 3A] FIG. 11 is an explanatory diagram for explaining a correction amount in a push switch. [Figure 3B] FIG. 11 is an explanatory diagram for explaining a correction amount in a slide switch. [Figure 4A] 4A and 4B are diagrams illustrating a first correction section and a second correction section in the push switch. [Figure 4B] 11 is a diagram showing a first correction unit and a second correction unit in the slide switch. FIG. [Figure 5A] This shows the state when the calculated vehicle body position is shifted to the right while driving straight under automatic steering. [Figure 5B] This shows the state when the calculated vehicle body position is shifted to the left while driving straight under automatic steering. [Figure 6] This is a view of the cover in front of the driver's seat as seen from the driver's seat side. [Figure 7] FIG. 2 is an explanatory diagram for explaining automatic steering. [Figure 8A] FIG. 4 is a diagram showing an example of an operation screen M1. [Figure 8B] FIG. 4 is a diagram showing a position deviation display unit. [Figure 9A] 13 is a diagram showing an example of the position deviation between the calculated vehicle body position W1 and the planned traveling line L2 displayed on the position deviation display unit. FIG. [Figure 9B] 13 is a diagram showing a state in which the position deviation between the corrected vehicle body position W3 and the intended traveling line L2 is substantially zero, displayed on the position deviation display unit. [Figure 9C] 13 is a diagram showing a state in which the position deviation between the corrected vehicle body position W3 and the intended traveling line L2 is large, the figure being displayed on the position deviation display unit. [Figure 10] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0017] Fig. 10 is a side view showing one embodiment of the work vehicle 1, and Fig. 10 is a plan view showing one embodiment of the work vehicle 1. In the case of this embodiment, the work vehicle 1 is a tractor. However, the work vehicle 1 is not limited to a tractor, and may be an agricultural machine (agricultural vehicle) such as a combine harvester or transplanter, or a construction machine (construction vehicle) such as a loader work machine.

[0018] In the following description, the front side (arrow A1 direction in FIG. 10) of the driver seated in the driver's seat 10 of the tractor (work vehicle) 1 will be referred to as the front, the rear side of the driver (arrow A2 direction in FIG. 10) as the rear, the left side of the driver (arrow B1 direction in FIG. 10) as the left side, and the right side of the driver (arrow B2 direction in FIG. 10) as the right side. In addition, the horizontal direction (arrow B3 direction in FIG. 10), which is perpendicular to the fore-and-aft direction of the work vehicle 1, will be referred to as the vehicle body width direction.

[0019] As shown in Fig. 10, the tractor 1 includes a body 3, a prime mover 4, and a transmission 5. The body 3 has a traveling device 7 and is capable of traveling. The traveling device 7 is a device having front wheels 7F and rear wheels 7R. The front wheels 7F may be of a tire type or a crawler type. The rear wheels 7R may also be of a tire type or a crawler type.

[0020] The prime mover 4 is a diesel engine, an electric motor, or the like, and in this embodiment is configured with a diesel engine. The transmission 5 is capable of switching the propulsive force of the traveling device 7 by shifting gears, and also capable of switching the traveling device 7 between forward and reverse. The vehicle body 3 is provided with a driver's seat 10.

[0021] Further, a coupling section 8 formed of a three-point link mechanism or the like is provided at the rear of the vehicle body 3. A working device can be attached and detached to the coupling section 8. By coupling the working device to the coupling section 8, the working device can be towed by the vehicle body 3. The working devices include a tilling device for tilling, a fertilizer spreading device for spreading fertilizer, a pesticide spreading device for spreading pesticide, a harvesting device for harvesting, a reaping device for reaping grass or the like, a spreading device for spreading grass or the like, a grass collecting device for collecting grass or the like, a shaping device for shaping grass or the like, and the like.

[0022] As shown in Fig. 1, the transmission 5 includes a main shaft (propeller shaft) 5a, a main speed change section 5b, an auxiliary speed change section 5c, a shuttle section 5d, a PTO power transmission section 5e, and a front speed change section 5f. The propeller shaft 5a is rotatably supported in a housing case (transmission case) of the transmission 5, and power is transmitted from the crankshaft of the engine 4 to the propeller shaft 5a. The main speed change section 5b has a plurality of gears and a shifter that changes the connection of the gears. The main speed change section 5b changes and outputs (changes the speed of) the rotation input from the propeller shaft 5a by appropriately changing the connection (meshing) of the plurality of gears with the shifter.

[0023] The sub-transmission unit 5c, like the main transmission unit 5b, has multiple gears and a shifter that changes the connection of the gears. The sub-transmission unit 5c changes and outputs (shifts) the rotation input from the main transmission unit 5b by appropriately changing the connection (meshing) of the multiple gears with the shifter.

[0024] The shuttle section 5d has a shuttle shaft 12 and a forward / reverse switching section 13. Power output from the sub-transmission section 5c is transmitted to the shuttle shaft 12 via gears or the like. The forward / reverse switching section 13 is composed of, for example, a hydraulic clutch, and switches the rotation direction of the shuttle shaft 12, i.e., the forward and reverse movement of the tractor 1, by engaging and disengaging the hydraulic clutch. The shuttle shaft 12 is connected to a rear wheel differential device 20R. The rear wheel differential device 20R rotatably supports a rear axle 21R to which the rear wheels 7R are attached.

[0025] The PTO power transmission section 5e has a PTO propulsion shaft 14 and a PTO clutch 15. The PTO propulsion shaft 14 is rotatably supported and is capable of transmitting power from the propulsion shaft 5a. The PTO propulsion shaft 14 is connected to a PTO shaft 16 via gears or the like. The PTO clutch 15 is composed of, for example, a hydraulic clutch, and switches between a state in which the power of the propulsion shaft 5a is transmitted to the PTO propulsion shaft 14 and a state in which the power of the propulsion shaft 5a is not transmitted to the PTO propulsion shaft 14 by switching the hydraulic clutch on and off.

[0026] The front transmission unit 5f has a first clutch 17 and a second clutch 18. The first clutch 17 and the second clutch 18 can transmit power from the drive shaft 5a, for example, the power of the shuttle shaft 12 is transmitted via a gear and a transmission shaft. The power from the first clutch 17 and the second clutch 18 can be transmitted to the front axle 21F via a front transmission shaft 22. Specifically, the front transmission shaft 22 is connected to a front wheel differential device 20F, and the front wheel differential device 20F rotatably supports the front axle 21F to which the front wheels 7F are attached.

[0027] The first clutch 17 and the second clutch 18 are composed of a hydraulic clutch or the like. An oil passage is connected to the first clutch 17, and the oil passage is connected to a first operating valve 25 to which hydraulic oil discharged from a hydraulic pump 33 is supplied. The first clutch 17 is switched between an engaged state and a disengaged state depending on the opening degree of the first operating valve 25. An oil passage is connected to the second clutch 18, and the oil passage is connected to a second operating valve 26. The second clutch 18 is switched between an engaged state and a disengaged state depending on the opening degree of the second operating valve 26. The first operating valve 25 and the second operating valve 26 are, for example, two-position switching valves with solenoid valves, and are switched between an engaged state and a disengaged state by energizing or deenergizing a solenoid of the solenoid valve.

[0028] When the first clutch 17 is in a disengaged state and the second clutch 18 is in an engaged state, the power of the shuttle shaft 12 is transmitted to the front wheels 7F through the second clutch 18. As a result, the front wheels 7F and the rear wheels 7R are driven by power in a four-wheel drive (4WD) state, and the rotation speeds of the front wheels 7F and the rear wheels 7R are substantially the same (4WD constant speed state). On the other hand, when the first clutch 17 is in an engaged state and the second clutch 18 is in a disengaged state, the vehicle is in a four-wheel drive state, and the rotation speed of the front wheels 7F is faster than the rotation speed of the rear wheels 7R (4WD speed increase state). Also, when the first clutch 17 and the second clutch 18 are in an engaged state, the power of the shuttle shaft 12 is not transmitted to the front wheels 7F, and the vehicle is in a two-wheel drive (2WD) state in which the rear wheels 7R are driven by power.

[0029] The tractor 1 is equipped with a positioning device 40. The positioning device 40 is a device that detects its own position (positioning information including latitude and longitude) by a satellite positioning system (positioning satellite) such as D-GPS, GPS, GLONASS, Hokuto, Galileo, and Michibiki. That is, the positioning device 40 receives a reception signal (position of the positioning satellite, transmission time, correction information, etc.) transmitted from the positioning satellite, and detects the position (e.g., latitude and longitude) based on the reception signal. The positioning device 40 has a receiving device 41 and an inertial measurement unit (IMU) 42. The receiving device 41 is a device that has an antenna and the like and receives a reception signal transmitted from the positioning satellite, and is attached to the vehicle body 3 separately from the inertial measurement unit 42. In this embodiment, the receiving device 41 is attached to a ROPS provided on the vehicle body 3. Note that the mounting location of the receiving device 41 is not limited to the embodiment.

[0030] The inertial measurement unit 42 has an acceleration sensor that detects acceleration, a gyro sensor that detects angular velocity, etc. The inertial measurement unit 42 is provided on the vehicle body 3, for example, below the driver's seat 10, and can detect the roll angle, pitch angle, yaw angle, etc. of the vehicle body 3.

[0031] As shown in Fig. 1, the tractor 1 is equipped with a steering device 11. The steering device 11 is a device capable of performing manual steering, in which the vehicle body 3 is steered by the driver's operation, and automatic steering, in which the vehicle body 3 is steered automatically without the driver's operation.

[0032] The steering device 11 has a steering handle (steering wheel) 30 and a steering shaft (rotating shaft) 31 that rotatably supports the steering handle 30. The steering device 11 also has an assist mechanism (power steering device) 32. The assist mechanism 32 assists the rotation of the steering shaft 31 (steering handle 30) by hydraulic pressure or the like. The assist mechanism 32 includes a hydraulic pump 33, a control valve 34 to which hydraulic oil discharged from the hydraulic pump 33 is supplied, and a steering cylinder 35 operated by the control valve 34. The control valve 34 is, for example, a three-position switching valve that can be switched by movement of a spool or the like, and switches in accordance with the steering direction (rotation direction) of the steering shaft 31. The steering cylinder 35 is connected to an arm (knuckle arm) 36 that changes the direction of the front wheels 7F.

[0033] Therefore, when the driver grips the steering wheel 30 and turns it in one direction or the other, the switching position and opening of the control valve 34 are switched corresponding to the rotation direction of the steering wheel 30, and the steering cylinder 35 expands or contracts to the left or right according to the switching position and opening of the control valve 34, thereby changing the steering direction of the front wheels 7F. In other words, the traveling direction of the vehicle body 3 can be changed to the left or right by manually steering the steering wheel 30.

[0034] Next, automatic steering will be described.

[0035] As shown in Fig. 2, when performing automatic steering, first, a driving reference line L1 is set before performing automatic steering. After setting the driving reference line L1, automatic steering can be performed by setting a planned driving line L2 parallel to the driving reference line L1. In automatic steering, the tractor 1 (vehicle body 3) is automatically steered in the traveling direction so that the vehicle body position measured by the positioning device 40 coincides with the planned driving line L2.

[0036] Specifically, before performing automatic steering, the tractor 1 (body 3) is moved to a predetermined position in the field (S1), and when the driver operates the steering change-over switch 52 provided on the tractor 1 at the predetermined position (S2), the body position measured by the positioning device 40 is set to the start point P10 of the traveling reference line L1 (S3). In addition, the tractor 1 (body 3) is moved from the start point P10 of the traveling reference line L1 (S4), and when the driver operates the steering change-over switch 52 at the predetermined position (S5), the body position measured by the positioning device 40 is set to the end point P11 of the traveling reference line L1 (S6). Therefore, a straight line connecting the start point P10 and the end point P11 is set as the traveling reference line L1.

[0037] After the travel reference line L1 is set (after S6), for example, the tractor 1 (body 3) is moved to a location different from the location where the travel reference line L1 was set (S7), and when the driver operates the steering changeover switch 52 (S8), a travel planned line L2 that is a straight line parallel to the travel reference line L1 is set (S9). After the travel planned line L2 is set, automatic steering is started, and the traveling direction of the tractor 1 (body 3) is changed to follow the travel planned line L2. For example, if the current body position is on the left side of the travel planned line L2, the front wheels 7F are steered to the right, and if the current body position is on the right side of the travel planned line L2, the front wheels 7F are steered to the left. During automatic steering, the travel speed (vehicle speed) of the tractor 1 (body 3) can be changed by the driver manually changing the operation amount of the accelerator member (accelerator pedal, accelerator lever) provided on the tractor 1 or changing the gear stage of the transmission 5.

[0038] Furthermore, after automatic steering has started, the driver can end the automatic steering by operating the steering changeover switch 52 at any point. That is, the end point of the planned travel line L2 can be set by ending automatic steering by operating the steering changeover switch 52. That is, the length from the start point to the end point of the planned travel line L2 can be set longer or shorter than the travel reference line L1. In other words, the planned travel line L2 is not associated with the length of the travel reference line L1, and the planned travel line L2 allows the vehicle to travel a distance longer than the length of the travel reference line L1 while undergoing automatic steering.

[0039] As shown in FIG. 1, the steering device 11 has an automatic steering mechanism 37. The automatic steering mechanism 37 is a mechanism that automatically steers the vehicle body 3, and automatically steers the vehicle body 3 based on the position of the vehicle body 3 (vehicle body position) detected by the positioning device 40. The automatic steering mechanism 37 includes a steering motor 38 and a gear mechanism 39. The steering motor 38 is a motor whose rotation direction, rotation speed, rotation angle, etc. can be controlled based on the vehicle body position. The gear mechanism 39 includes a gear provided on the steering shaft 31 and rotating together with the steering shaft 31, and a gear provided on the rotation shaft of the steering motor 38 and rotating together with the rotation shaft. When the rotation shaft of the steering motor 38 rotates, the steering shaft 31 automatically rotates (turns) via the gear mechanism 39, and the steering direction of the front wheels 7F can be changed so that the vehicle body position coincides with the planned travel line L2.

[0040] 1, the tractor 1 is equipped with a display device 45. The display device 45 is a device capable of displaying various information related to the tractor 1, and is capable of displaying at least driving information of the tractor 1. The display device 45 is provided in front of the driver's seat 10.

[0041] As shown in Fig. 1, the tractor 1 is provided with a setting switch 51. The setting switch 51 is a switch for switching to a setting mode in which at least settings before the start of automatic steering are performed. The setting mode is a mode in which various settings related to automatic steering are performed before the start of the automatic steering, for example, a mode in which the start point and end point of the driving reference line L1 are set.

[0042] The setting switch 51 can be switched between ON and OFF, and when it is ON it outputs a signal indicating that the setting mode is valid, and when it is OFF it outputs a signal indicating that the setting mode is invalid. Furthermore, when the setting switch 51 is ON it outputs a signal indicating that the setting mode is valid to the display device 45, and when it is OFF it outputs a signal indicating that the setting mode is invalid to the display device 45.

[0043] The tractor 1 is provided with a steering changeover switch 52. The steering changeover switch 52 is a switch for switching the start or end of automatic steering. Specifically, the steering changeover switch 52 can be switched from a neutral position to up, down, forward, or backward, and outputs the start of automatic steering when the steering changeover switch 52 is switched from the neutral position to down while the setting mode is active, and outputs the end of automatic steering when the steering changeover switch 52 is switched from the neutral position to up while the setting mode is active. In addition, when the steering changeover switch 52 is switched from the neutral position to backward while the setting mode is active, the steering changeover switch 52 outputs a command to set the current vehicle body position to the start point P10 of the driving reference line L1, and when the steering changeover switch 52 is switched from the neutral position to forward while the setting mode is active, the steering changeover switch 52 outputs a command to set the current vehicle body position to the end point P11 of the driving reference line L1.

[0044] The tractor 1 is equipped with a correction switch 53. The correction switch 53 is a switch that corrects the vehicle body position (latitude, longitude) measured by the positioning device 40. In other words, the correction switch 53 is a switch that corrects the vehicle body position (referred to as a calculated vehicle body position) calculated using satellite signals (position of the positioning satellite, transmission time, correction information, etc.) and measurement information (acceleration, angular velocity) measured by the inertial measurement unit 42.

[0045] The correction switch 53 is configured as a push switch that can be pressed or a slide switch that can be slid. Below, the cases where the correction switch 53 is a push switch and a slide switch will be described.

[0046] When the correction switch 53 is a push switch, the amount of correction is set based on the number of times the push switch is operated. The amount of correction is determined by: correction amount = number of operations x amount of correction per number of operations (amount of correction per unit). For example, as shown in FIG. 3A, the amount of correction increases by several centimeters or several tens of centimeters each time the push switch is operated. The number of times the push switch is operated is input to the first control device 60A, which sets (calculates) the amount of correction based on the number of operations. The first control device 60A is capable of changing the amount of correction per predetermined operation of the push switch, i.e., per number of operations. . Display device 45 When a predetermined operation is performed on the display device 45, the first control device 60A sets the correction amount in the display device 45. Setting screen Display. On the Settings screen Enter the correction amount per push switch operation (correction amount per unit). The setting input section It will be displayed. Setting input section The correction amount per unit can be input by operating the display device 45. In the setting input section The input correction amount per unit can be stored in the first control device 60A. In the setting input section By inputting the correction amount per unit, for example, the correction amount per unit shown in FIG. 3A can be changed from 2 cm to 4 cm.

[0047] Furthermore, when the correction switch 53 is a slide switch, the correction amount is set based on the operation amount (displacement amount) of the slide switch. For example, the correction amount is determined by the correction amount=the displacement amount from a predetermined position. For example, as shown in FIG. 3B, the correction amount increases by several centimeters or several tens of centimeters every time the displacement amount of the slide switch increases by 5 mm. The operation amount (displacement amount) of the slide switch is input to the first control device 60A, which sets (calculates) the correction amount based on the displacement amount. Even if the correction switch 53 is a slide switch, the correction amount can be changed in the same way as with a push switch.

[0048] Display device 45 When a predetermined operation is performed on the display device 45, the first control device 60A sets the correction amount in the display device 45. Setting screen Display. On the Settings screen is used to input a correction amount (amount of correction per unit) for a given operation of the slide switch, i.e., a displacement amount of the slide switch. The setting input section It will be displayed. Setting input section The correction amount per unit can be input by operating the display device 45, and the input correction amount per unit can be stored in the first control device 60A. In the setting input section By inputting the correction amount per unit, for example, the correction amount (correction amount per unit) for every 5 mm increase in the displacement amount can be changed from 2 cm to 4 cm as shown in Fig. 3B. Note that the method of increasing the correction amount and the rate of increase are not limited to the above-mentioned values.

[0049] 4A and 4B, the correction switch 53 has a first correction unit 53A and a second correction unit 53B. The first correction unit 53A is a unit that issues a command to correct the vehicle body position corresponding to one side in the width direction of the vehicle body 3, i.e., the left side. The second correction unit 53B is a unit that issues a command to correct the vehicle body position corresponding to the other side in the width direction of the vehicle body 3, i.e., the right side.

[0050] As shown in FIG. 4A, when the correction switch 53 is a push switch, the first correction unit 53A and the second correction unit 53B are ON or OFF switches that are automatically restored every time they are operated. The switch constituting the first correction unit 53A and the switch constituting the second correction unit 53B are integrated. The switch constituting the first correction unit 53A and the switch constituting the second correction unit 53B may be arranged apart from each other. As shown in FIG. 3A, every time the first correction unit 53A is pressed, the correction amount (left correction amount) corresponding to the left side of the vehicle body 3 increases. Also, every time the second correction unit 53B is pressed, the correction amount (right correction amount) corresponding to the right side of the vehicle body 3 increases.

[0051] As shown in FIG. 4B, when the correction switch 53 is a slide switch, the first correction unit 53A and the second correction unit 53B include a knob 55 that moves left or right along the longitudinal direction of the long hole. When the correction switch 53 is a slide switch, the first correction unit 53A and the second correction unit 53B are arranged spaced apart from each other in the width direction. As shown in FIG. 3B, when the knob 55 is gradually displaced leftward from a predetermined reference position, the left correction amount increases according to the amount of displacement. Also, when the knob 55 is gradually displaced rightward from a predetermined reference position, the right correction amount increases according to the amount of displacement. Note that, as shown in FIG. 4B, when the correction switch 53 is a slide switch, the first correction unit 53A and the second correction unit 53B may be integrally formed, the reference position of the knob 55 is set to the center, and when the knob 55 is moved leftward from the reference position, the left correction amount is set, and when the knob 55 is moved rightward from the middle position, the right correction amount is set.

[0052] Next, the relationship between the correction amount (left correction amount, right correction amount) by the correction switch 53, the intended travel line L2, and the behavior (travel trajectory) of the tractor 1 (vehicle body 3) will be described.

[0053] FIG. 5A shows a state in which the calculated vehicle body position W1 is shifted to the right while moving straight under automatic steering. As shown in FIG. 5A, in a state in which automatic steering is started, when the actual position (actual position W2) of the tractor 1 (vehicle body 3) coincides with the calculated vehicle body position W1 and the actual position W2 coincides with the planned travel line L2, the tractor 1 travels along the planned travel line L2. That is, in a section P1 in which there is no error in the positioning of the positioning device 40 and the vehicle body position (calculated vehicle body position W1) detected by the positioning device 40 is the same as the actual position W2, the tractor 1 travels along the planned travel line L2. Note that, when there is no error in the positioning of the positioning device 40 and no correction is performed, the calculated vehicle body position W1 and the vehicle body position (corrected vehicle body position) W3 corrected by the correction amount are the same value. The corrected vehicle body position W3 is the corrected vehicle body position W3 = calculated vehicle body position W1 - correction amount.

[0054] Here, in the vicinity of position P20, even though the actual position W2 is not deviated from the planned travel line L2, an error occurs in the positioning of the positioning device 40 due to various influences, and the vehicle body position W1 detected by the positioning device 40 deviates to the right from the planned travel line L2 (actual position W2), and if the deviation amount W4 is maintained, the tractor 1 determines that a deviation has occurred between the calculated vehicle body position W1 and the planned travel line L2, and steers the tractor 1 to the left so as to eliminate the deviation amount W4 between the calculated vehicle body position W1 and the planned travel line L2. Then, the actual position W2 of the tractor 1 is shifted to the planned travel line L2 by steering to the left. After that, it is assumed that the driver notices that the tractor 1 is deviated from the planned travel line L2, and steers the second correction unit 53B at position P21 to increase the right correction amount from zero. A right correction amount is added to the calculated vehicle body position W1, and the corrected vehicle body position (corrected vehicle body position) W3 can be made substantially the same as the actual position W2. In other words, by setting the right correction amount by the second correction unit 53B, the vehicle body position of the positioning device 40 can be corrected in a direction that eliminates the deviation amount W4 that occurs near the position P20. Note that, as shown in position P21 in FIG. 5A, if the actual position W2 of the tractor 1 is away from the planned travel line L2 to the left after the vehicle body position is corrected, the tractor 1 is steered to the right, and the actual position W2 of the tractor 1 can be made to coincide with the planned travel line L2.

[0055] Fig. 5B shows a state in which the calculated vehicle body position W1 is shifted to the left while traveling straight under automatic steering. As shown in Fig. 5B, when automatic steering is started, if the actual position W2 and the calculated vehicle body position W1 coincide with each other and the actual position W2 and the planned travel line L2 coincide with each other, the tractor 1 travels along the planned travel line L2, as in Fig. 5A. That is, as in Fig. 5A, in the section P2 where there is no error in the positioning of the positioning device 40, the tractor 1 travels along the planned travel line L2. Also, as in Fig. 5A, the calculated vehicle body position W1 and the corrected vehicle body position W3 are the same value.

[0056] Here, if an error occurs in the positioning of the positioning device 40 due to various influences at the position P22, and the vehicle body position W1 detected by the positioning device 40 is shifted to the left with respect to the actual position W2, and the shift amount W5 is maintained, the tractor 1 steers the tractor 1 to the right so as to eliminate the shift amount W5 between the calculated vehicle body position W1 and the planned travel line L2. Then, suppose that the driver notices that the tractor 1 is shifted from the planned travel line L2, and steers the first correction unit 53A at the position P23 to increase the left correction amount from zero. Then, the left correction amount is added to the calculated vehicle body position W1, and the corrected vehicle body position (corrected vehicle body position) W3 can be made substantially the same as the actual position W2. In other words, by setting the left correction amount by the first correction unit 53A, the vehicle body position of the positioning device 40 can be corrected in a direction that eliminates the shift amount W5 that occurred near the position P22. In addition, as shown in position P23 in Figure 5B, if, after correcting the vehicle position, the actual position W2 of the tractor 1 is away to the right of the planned driving line L2, the tractor 1 is steered to the left, and the actual position W2 of the tractor 1 can be aligned with the planned driving line L2.

[0057] Next, the setting switch 51, the correction switch 53, and the screen changeover switch 54 will be described.

[0058] 6, the outer periphery of the steering shaft 31 is covered by a steering post 180. The outer periphery of the steering post 180 is covered by a cover 177. The cover 177 is provided in front of the driver's seat 10. The cover 177 includes a panel cover 178 and a column cover 179.

[0059] The panel cover 178 supports the display device 45. A support portion 178e that supports the display device 45 is provided on an upper plate portion 178a of the panel cover 178. The support portion 178e supports the display device 45 in front of the steering shaft 31 and below the steering handle 30. The upper plate portion 178a also has a mounting surface 178f to which the setting switch 51, the correction switch 53, and the screen changeover switch 54 are attached. The mounting surface 178f is provided behind the support portion 178e and below the steering handle 30. The support portion 178e and the mounting surface 178f are continuous with each other, the support portion 178e being located in front of the upper plate portion 178a, and the mounting surface 178f being located in the rear of the upper plate portion 178a. The setting switch 51, the correction switch 53, and the screen changeover switch 54 are attached to the mounting surface 178f. As a result, the setting switch 51, the correction switch 53, and the screen changeover switch 54 are arranged around the steering shaft 31.

[0060] A shuttle lever 181 protrudes from the left plate portion 178b of the panel cover 178. The shuttle lever 181 is a member that switches the traveling direction of the vehicle body 3. To explain in more detail, by operating (swinging) the shuttle lever 181 forward, the forward / reverse switching unit 13 is placed in a state in which it outputs forward power to the traveling device 7, and the traveling direction of the vehicle body 3 is switched to the forward direction. In addition, by operating (swinging) the shuttle lever 181 backward, the forward / reverse switching unit 13 is placed in a state in which it outputs reverse power to the traveling device 7, and the traveling direction of the vehicle body 3 is switched to the reverse direction. When the shuttle lever 181 is in the neutral position, no power is output to the traveling device 7.

[0061] The column cover 179 is disposed below the steering wheel 30, and covers the periphery of the upper part of the steering shaft 31. The column cover 179 is formed in a substantially rectangular tubular shape, and protrudes upward from the mounting surface 178f of the panel cover 178. In other words, the mounting surface 178f is provided around the column cover 179. Therefore, the setting switch 51, the correction switch 53, and the screen changeover switch 54 attached to the mounting surface 178f are disposed around the column cover 179.

[0062] Next, a detailed description will be given of the locations of the setting switch 51, the steering changeover switch 52, the correction switch 53, and the screen changeover switch 54. As shown in Fig. 6, the setting switch 51, the steering changeover switch 52, the correction switch 53, and the screen changeover switch 54 are arranged around the steering shaft 31.

[0063] The setting switch 51 is disposed on one side (left side) of the steering shaft 31. The steering changeover switch 52 is disposed on one side (left side) of the steering shaft 31. In this embodiment, the steering changeover switch 52 is composed of a swingable lever. The steering changeover switch 52 can swing around a base end provided on the steering shaft 31 side as a fulcrum. The base end of the steering changeover switch 52 is provided inside the column cover 179. The steering changeover switch 52 protrudes from one side (left side) of the column cover 179.

[0064] The correction switch 53 is disposed on the other side (right side) of the steering shaft 31. More specifically, the correction switch 53 is disposed on the right side and rear (diagonally rear right) of the steering shaft 31. In terms of its positional relationship with the column cover 179, the correction switch 53 is disposed on the right side and rear (diagonally rear right) of the column cover 179. In terms of its positional relationship with the mounting surface 178f of the panel cover 178, the correction switch 53 is disposed on the right rear part of the mounting surface 178f. By disposing the correction switch 53 on the rear part of the inclined mounting surface 178f, it is possible to ensure a long distance between the correction switch 53 and the steering wheel 30. This makes it possible to more reliably prevent unintentional operation of the correction switch 53 and steering of the steering wheel 30.

[0065] The screen changeover switch 54 is disposed on the other side (right side) of the steering shaft 31. More specifically, the screen changeover switch 54 is disposed to the right and in front (diagonally forward right) of the steering shaft 31. In terms of its positional relationship with the column cover 179, the screen changeover switch 54 is disposed to the right and in front (diagonally forward right) of the column cover 179. In terms of its positional relationship with the mounting surface 178f of the panel cover 178, the screen changeover switch 54 is disposed at the right front part of the mounting surface 178f. The screen changeover switch 54 is also disposed in front of the correction switch 53.

[0066] As described above, the setting switch 51, the steering changeover switch 52, the correction switch 53, and the screen changeover switch 54 are arranged around the steering shaft 31. In other words, the setting switch 51, the steering changeover switch 52, the correction switch 53, and the screen changeover switch 54 are concentrated around the steering shaft 31. Therefore, the driver can clearly understand the position of each switch at a glance. In addition, the driver can operate each switch without changing his / her posture while remaining seated in the driver's seat 10. Therefore, operability is improved and erroneous operation can be prevented. Also, the harness (wiring) arranged from each switch can be shortened.

[0067] Incidentally, the above-mentioned switches may be arranged with the left and right interchanged. That is, one side may be the left and the other side may be the right, or one side may be the right and the other side may be the left. Specifically, for example, the setting switch 51 and the steering changeover switch 52 may be arranged on the right side of the steering shaft 31, and the correction switch 53 may be arranged on the left side of the steering shaft 31.

[0068] As shown in Fig. 1, the tractor 1 is equipped with a plurality of control devices 60. The plurality of control devices 60 are devices that control the travel system, the work system, calculate the vehicle body position, and the like in the tractor 1. The plurality of control devices 60 are a first control device 60A, a second control device 60B, and a third control device 60C.

[0069] The first control device 60A receives the reception signal (received information) received by the receiving device 41 and the measurement information (acceleration, angular velocity, etc.) measured by the inertial measurement device 42, and determines the vehicle body position based on the reception information and the measurement information. For example, when the correction amount by the correction switch 53 is zero, that is, when the correction of the vehicle body position by the correction switch 53 is not commanded, the first control device 60A does not perform correction on the calculated vehicle body position W1 calculated from the reception information and the measurement information, and determines the calculated vehicle body position W1 as the vehicle body position to be used during automatic steering. On the other hand, when the correction of the vehicle body position by the correction switch 53 is commanded, the first control device 60A sets the correction amount of the vehicle body position based on either the number of times the correction switch 53 is operated or the operation amount (displacement amount) of the correction switch 53, and determines the corrected vehicle body position W3 obtained by correcting the calculated vehicle body position W1 with the correction amount as the vehicle body position to be used during automatic steering.

[0070] The first control device 60A sets a control signal based on the vehicle body position (calculated vehicle body position W1, corrected vehicle body position W3) and the intended travel line L2, and outputs the control signal to the second control device 60B. The second control device 60B controls the steering motor 38 of the automatic steering mechanism 37 based on the control signal output from the first control device 60A so that the vehicle body 3 travels along the intended travel line L2.

[0071] As shown in Fig. 7, when the deviation between the vehicle body position and the planned travel line L2 is less than the threshold, the second control device 60B maintains the rotation angle of the rotation shaft of the steering motor 38. When the deviation between the vehicle body position and the planned travel line L2 is equal to or greater than the threshold and the tractor 1 is located on the left side of the planned travel line L2, the second control device 60B rotates the rotation shaft of the steering motor 38 so that the steering direction of the tractor 1 is to the right. When the deviation between the vehicle body position and the planned travel line L2 is equal to or greater than the threshold and the tractor 1 is located on the right side of the planned travel line L2, the second control device 60B rotates the rotation shaft of the steering motor 38 so that the steering direction of the tractor 1 is to the left. In the above-described embodiment, the steering angle of the steering device 11 is changed based on the deviation between the vehicle body position and the planned travel line L2. However, when the orientation of the planned travel line L2 and the orientation (vehicle body orientation) F1 of the traveling direction (traveling direction) of the tractor 1 (vehicle body 3) are different, that is, when the angle θ of the vehicle body orientation F1 with respect to the planned travel line L2 is equal to or greater than a threshold value, the second control device 60B may set the steering angle so that the angle θ is zero (the vehicle body orientation F1 coincides with the orientation of the planned travel line L2). In addition, the second control device 60B may set the final steering angle in automatic steering based on the steering angle calculated based on the deviation (position deviation) and the steering angle calculated based on the orientation (orientation deviation θ). The setting of the steering angle in automatic steering in the above-described embodiment is an example and is not limited.

[0072] The third control device 60C raises and lowers the connecting portion 8 in response to the operation of an operating member provided around the driver's seat 10. The first control device 60A, the second control device 60B, and the third control device 60C may be integrated. In addition, the control of the traveling system, the control of the working system, and the calculation of the vehicle body position described above are not limited.

[0073] Settings related to the traveling of the vehicle body 3 can be made using the display device 45.

[0074] The display device 45 will now be described in detail.

[0075] 1, the display device 45 can acquire various information detected by the detection device 47 via an in-vehicle network or the like. The detection device 47 is an accelerator pedal sensor, a shift lever detection sensor, a crank position sensor, a fuel sensor, a water temperature sensor, a prime mover rotation sensor, a steering angle sensor, an oil temperature sensor, an axle rotation sensor, etc. For example, the display device 45 can display, as driving information, the remaining fuel amount detected by the fuel sensor, the water temperature value detected by the water temperature sensor, the prime mover rotation speed detected by the prime mover rotation sensor, etc.

[0076] Furthermore, the display device 45 can obtain information on various switches, for example, information on the setting switch 51, the steering changeover switch 52, and the correction switch 53. The display device 45 can obtain ON / OFF information on the setting switch 51, information on the start and end of automatic steering in the steering changeover switch 52, and information on commands for the start point P10 and end point P11 of the driving reference line L1 in the steering changeover switch 52.

[0077] As shown in Fig. 6, the display device 45 includes a display unit 46 that displays various information. The display unit 46 includes a fixed display unit 46A that displays warnings and the like, and a variable display unit 46B that can change the information to be displayed. The fixed display unit 46A has a panel on which figures for warnings and the like are displayed, and an illumination unit such as an LED that illuminates the figures on the panel with a light source. The variable display unit 46B is formed of a panel such as an organic electroluminescence (EL) panel or a liquid crystal panel, and displays various information related to the operation (travel) of the tractor 1, etc.

[0078] The display device 45 can display the amount of deviation (deviation) between the vehicle body 3 and the planned traveling line L2. Specifically, the display device 45 displays the position deviation (amount of deviation) between the vehicle body position (calculated vehicle body position) W1 detected by the positioning device 40 and the planned traveling line L2 as the deviation. When a predetermined operation is performed on the display device 45, the display device 45 displays the driving screen M1.

[0079] The driving screen M1 has a driving display section 61 that displays driving information. The driving display section 61 includes a rotation display section 62 that displays the rotation speed of the prime mover 4 (prime mover rotation speed) as driving information. The rotation display section 62 includes a level display section 63. The level display section 63 is a section that displays the prime mover rotation speed in stages. For example, the level display section 63 includes a scale section 65 and an indicator section 80. The scale section 65 has, for example, a first line 65A and a plurality of second lines 65B that are allocated at a predetermined interval along the first line 65A. The scale section 65 also has a third line 65C that is spaced apart from the first line 65A at a predetermined interval. The first line 65A and the third line 65C are formed, for example, in a semicircular shape, with one end side (for example, the left side) being the minimum value and the other end side (for example, the right side) being the maximum value.

[0080] The indicator portion 80 is a bar whose length changes according to the magnitude of the prime mover rotation speed. For example, the indicator portion 80 is located between the first line 65A and the third line 65C, and when the value of the prime mover rotation speed is the minimum value of zero, the indicator portion 80 is located at one end side (left side) of the first line 65A and the third line 65C and has the shortest length, and when the value of the prime mover rotation speed is the maximum value, the indicator portion 80 extends from one end side (left side) of the first line 65A and the third line 65C to the other end side (right side) of the first line 65A and the third line 65C and has the longest length. The rotation display portion 62 includes a numeric display portion 64. The numeric display portion 64 displays the prime mover rotation speed in numbers. For example, the rotation display portion 62 is located inside the semicircle of the first line 65A and the third line 65C.

[0081] Therefore, according to the operation display unit 61, the prime mover rotation speed, such as the engine rotation speed, can be displayed in stages by the level display unit 63 and can also be displayed numerically by the rotation display unit 62.

[0082] The driving screen M1 has an icon display section 67 that displays a plurality of icon sections 66. The icon display section 67 is a section that displays various information using the icon sections 66. That is, settings related to driving such as automatic steering, for example, settings set in a setting mode, are displayed in the icon section 66. The icon display section 67 is located in a position different from the driving display section 61, for example, at the top of the driving screen M1.

[0083] The multiple icon sections 66 are a first icon section 66A, a second icon section 66B, a third icon section 66C, a fourth icon section 66D, a fifth icon section 66E, a sixth icon section 66F, and a seventh icon section 66G. Note that the driving screen M1 does not need to have all of the multiple icon sections 66 (66A, 66B, 66C, 66D, 66E, 66F, 66G) and is not limited to the above-mentioned embodiment.

[0084] The first icon section 66A is displayed when a warning occurs. The second icon section 66B is displayed when a start point P10 of the driving reference line L1 is set. The third icon section 66C is displayed when an end point P11 of the driving reference line L1 is set.

[0085] The fourth icon section 66D is displayed when automatic steering is permitted. For example, the fourth icon section 66D is displayed when the setting mode is enabled, the setting of the driving reference line L1 is completed, and the direction determination section 207 of the second control device 60B permits automatic steering. By looking at the fourth icon section 66D, the operator can understand that automatic steering is permitted. Then, the operator can start automatic steering by operating the steering changeover switch 52.

[0086] The fifth icon section 66E is displayed when the connector 8 is in the lifted or lowered state. The sixth icon section 66F is displayed when the 4WD is in the accelerated state. The seventh icon section 66G changes color, etc. according to the reception sensitivity of the receiving device 41.

[0087] As shown in FIG. 8A and FIG. 8B, the driving screen M1 has a position deviation display section 68. The position deviation display section 68 is a section that displays the position deviation (deviation amount) between the calculated vehicle body position W1 and the planned driving line L2 in stages. The position deviation display section 68 includes a scale section 68a and an indicator section 68b. The scale section 68a includes an origin 68a1 and a data line 68a2 that extends from the origin 68a1 in the horizontal direction on the driving screen M1. The origin 68a1 indicates a point where the position deviation is zero, and is provided at the center of the data line 68a2 in the longitudinal direction. The data line 68a2 is a section that indicates the magnitude of the position deviation, and the opposite side to the origin 68a1 is set to a maximum value. In the data line 68a2, the left side (one side) of the origin 68a1 is a region (portion) that indicates a position deviation when the vehicle body 3 is displaced to the left (one side) from the planned traveling line L2, and the right side (the other side) of the origin 68a1 is a region (portion) that indicates a position deviation when the vehicle body 3 is displaced to the right (the other side) from the planned traveling line L2. In addition, the data line 68a2 shows auxiliary scales divided into a plurality of steps, and the magnitude of the position deviation can be grasped by the indicator portion 68b pointing to the auxiliary scales.

[0088] The indicator portion 68b is a portion indicating the magnitude of the current position deviation, and moves along the data line 68a2. When the position deviation is zero, the indicator portion 68b is located at the center of the longitudinal direction of the data line 68a2 and coincides with the origin 68a1. When the vehicle body 3 is displaced to the left (one side) from the planned travel line L2 and the position deviation is at the maximum value, the indicator portion 68b is located at the left end of the data line 68a2. When the vehicle body 3 is displaced to the right (the other side) from the planned travel line L2 and the position deviation is at the maximum value, the indicator portion 68b is located at the right end of the data line 68a2. For example, when the position deviation is 1 cm, the indicator portion 68b moves left or right from the origin 68a1 by one scale of the data line 68a2. When the position deviation is 5 cm, the indicator portion 68b moves left or right from the origin 68a1 by five scales of the data line 68a2. The numerical value of the position deviation is merely an example and is not limiting.

[0089] In this way, by displaying the result detected by the positioning device 40, that is, the position deviation (deviation amount) between the calculated vehicle body position W1 and the planned travel line L2 on the position deviation display unit 68, the timing of correction by the correction switch 53 and the presence or absence of correction can be easily understood. For example, during automatic steering, if the position deviation is displayed on the position deviation display unit 68 even though the actual position W2 of the tractor 1 (vehicle body 3) and the planned travel line L2 match, the driver (operator) can determine that the position deviation displayed on the position deviation display unit 68 is due to the positioning error of the positioning device 40. If the position deviation is increasing due to the positioning error of the positioning device 40, as described above, the correction switch 53 can be operated to add a correction amount to the calculated vehicle body position W1, thereby suppressing the movement of the tractor 1 (vehicle body 3) due to the positioning error of the positioning device 40.

[0090] In the embodiment described above, the position deviation display unit 68 displayed the position deviation between the calculated vehicle body position W1 and the planned traveling line L2, but at least after the operation of the correction switch 53, it may also display the position deviation between the corrected vehicle body position W3 and the planned traveling line L2, which is the position deviation after correction by the correction switch 53. For convenience of explanation below, the position deviation between the calculated vehicle body position W1 and the planned traveling line L2 will be referred to as the "first position deviation W10", and the position deviation between the corrected vehicle body position W3 and the planned traveling line L2 will be referred to as the "second position deviation W11".

[0091] Specifically, as shown in Fig. 9A, after automatic steering is started, when the correction switch 53 is not operated, the position deviation display unit 68 displays the first position deviation W10 (S51). Furthermore, after automatic steering is started, when the correction switch 53 is operated (either the first correction unit 53A or the second correction unit 53B is operated), the position deviation display unit 68 switches the display from the first position deviation W10 to the second position deviation W11 (S52), as shown in Fig. 9B and Fig. 9C. For example, after the correction switch 53 is operated, the indicator unit 68b indicates the value of the second position deviation W11 on the scale unit 68a.

[0092] FIG. 9A shows a state in which the first position deviation W10 is displayed on the left side of the position deviation display unit 68 due to the positioning error of the positioning device 40, even though the actual position W2 of the tractor 1 (body 3) and the planned travel line L2 coincide with each other. FIG. 9B shows a state in which the first position deviation W10 occurs due to the positioning error of the positioning device 40 as in FIG. 9A, but the second position deviation W11 is displayed on the position deviation display unit 68 by operating the first correction unit 53A. As shown in FIG. 9B, when the second position deviation W11 displayed on the position deviation display unit 68 is approximately zero, it can be determined that the first correction unit 53A has performed the correction appropriately. On the other hand, when the second position deviation W11 displayed on the position deviation display unit 68 after the operation of the first correction unit 53A is not zero but is relatively large, it can be determined that the correction amount by the operation of the first correction unit 53A is small. That is, if the second position deviation W11 displayed on the position deviation display unit 68 is large after operating the first correction unit 53A of the correction switch 53, the driver knows that it is necessary to operate the first correction unit 53A to increase the amount of correction. In this case, the driver operates the first correction unit 53A until the second position deviation W11 becomes zero, as shown in Fig. 9B. In this way, by displaying the second position deviation W11 on the position deviation display unit 68, it is possible to determine whether the amount of correction achieved by operating the correction switch 53 is appropriate.

[0093] Furthermore, if the second position deviation W11 displayed on the position deviation display unit 68 becomes zero as shown in Fig. 9B after the first correction unit 53A of the correction switch 53 is operated, and then increases after a certain time has elapsed as shown in Fig. 9C, it can be determined that the positioning error of the positioning device 40 has been eliminated. In this case, the driver can stabilize the behavior of the tractor 1 (body 3) by performing an operation to set the amount of correction by the correction switch 53 to zero.

[0094] The work vehicle 1 is equipped with a drivable body 3, a steering wheel 30 for steering the body 3 by a rotation operation, a positioning device 40 provided on the body 3 and detecting the body position, which is the position of the body 3, based on a signal from a positioning satellite, a correction switch 53 for issuing a command to correct the body position detected by the positioning device 40, an automatic steering mechanism 37 capable of automatically steering the body 3 based on the body position detected by the positioning device 40 and a planned travel line L2, and a display device 45 capable of displaying the position deviation between the body position detected by the positioning device 40 and the planned travel line L2. According to this, when the body position can be corrected by the correction switch 53, the display device 45 can display the position deviation between the body position detected by the positioning device 40 (calculated body position) and the planned travel line L2. Therefore, in a situation where the tractor 1 (body 3) and the planned travel line L2 actually coincide with each other, when the position deviation between the calculated body position and the planned travel line L2 is displayed on the display device 45, the driver (operator) can understand that the position deviation is occurring due to a positioning error by the positioning device 40. In other words, by looking at the position deviation displayed on the display device 45, the driver can understand the influence of the positioning error (positioning accuracy) by the positioning device 40, and when a positioning error exists, the calculated body position used for automatic steering can be corrected by the correction switch 53.

[0095] The display device 45 displays the position deviation between the intended travel line L2 and the corrected vehicle body position, which is the vehicle body position corrected by the correction switch 53. This allows the user to grasp the position deviation of the intended travel line L2 from the corrected vehicle body position after operating the correction switch 53.

[0096] The correction switch 53 includes a first correction unit 53A that commands correction of the vehicle body position on one side in the width direction of the vehicle body 3, and a second correction unit 53B that commands correction of the vehicle body position on the other side in the width direction of the vehicle body. This makes it possible to easily correct the vehicle body position on one side of the vehicle body 3 or the vehicle body position on the other side of the vehicle body 3.

[0097] The work vehicle 1 is equipped with a control device 60 to which the correction switch 53 is connected and which controls the automatic steering mechanism 37, and the control device 60 sets the amount of correction of the vehicle body position based on the number of times the correction switch 53 is operated. This makes it possible to set (change) the amount of correction depending on the number of times the correction switch 53 is operated.

[0098] The control device 60 changes the amount of correction corresponding to one operation of the correction switch 53. This allows the amount of correction when the correction switch 53 is operated once to be changed, so that the state of automatic steering of the vehicle body 3 caused by the operation of the correction switch 53 can be changed according to various situations. For example, by reducing the amount of correction when the correction switch 53 is operated once, fine adjustments can be made in the automatic steering, and by increasing the amount of correction when the correction switch 53 is operated once, rough adjustments can be made in the automatic steering.

[0099] The control device 60 changes the amount of correction per operation amount of the correction switch 53. This allows the amount of correction when the correction switch 53 is operated a predetermined amount to be changed, so that the state of automatic steering of the vehicle body 3 caused by the operation of the correction switch 53 can be changed according to various situations. For example, by reducing the amount of correction when the correction switch 53 is operated a predetermined amount, fine adjustments can be made in the automatic steering, and by increasing the amount of correction when the correction switch 53 is operated a predetermined amount, rough adjustments can be made in the automatic steering.

[0100] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0101] In the above-mentioned embodiment, the display device 45 displays the position deviation, but it may display the orientation deviation between the orientation of the planned travel line L2 and the orientation (body orientation) F1 of the traveling direction (traveling direction) of the tractor 1 (body 3). When the orientation deviation is displayed on the display device 45, the above-mentioned position deviation may be read as the orientation deviation. [Explanation of symbols]

[0102] 1 Work vehicle 3. Body 30 Steering wheel 37 Automatic steering mechanism 40 Positioning device 45 Display device 53 Correction Switch 53A First correction section 53B 2nd correction section 60 Control device L2 Planned running line

Claims

1. A drivable vehicle body; A connecting portion capable of connecting a working device for performing work to the vehicle body; a steering handle for rotating the vehicle body; a positioning device provided on the vehicle body and detecting a position of the vehicle body based on a signal from a positioning satellite; an automatic steering mechanism capable of automatically steering the vehicle body based on the vehicle body position detected by the positioning device and a planned driving line; a display device capable of displaying a deviation between the vehicle body position detected by the positioning device and the planned traveling line; a correction switch for setting the amount of correction; Equipped with the automatic steering mechanism is capable of performing the automatic steering based on the deviation changed by the correction amount set by the correction switch, The display device is a work vehicle that displays a screen for changing the correction amount of the operation unit of the correction switch.

2. a control device to which the correction switch is connected and which controls the automatic steering mechanism, The control device sets the correction amount based on the number of times the correction switch is operated, The work vehicle according to claim 1 , wherein the correction amount per operation is a correction amount per one operation of the correction switch.

3. 3. The work vehicle according to claim 2, wherein the control device changes the correction amount corresponding to one operation of the correction switch based on information displayed on the screen and input to a setting input unit that accepts input of the correction amount for each operation.

4. a control device to which the correction switch is connected and which controls the automatic steering mechanism, The control device sets the correction amount based on an operation amount of the correction switch, The work vehicle according to claim 1 , wherein the correction amount per operation unit is a correction amount per a predetermined operation amount of the correction switch.

5. 5. The work vehicle according to claim 4, wherein the control device changes the correction amount per operation amount of the correction switch based on information displayed on the screen and input to a setting input unit that accepts input of the correction amount for the operation unit.

6. The display device includes: When a start point of a travel reference line used for setting the planned travel line is set, a first icon is displayed on the screen; The work vehicle according to any one of claims 1 to 5, wherein a second icon is displayed on the screen when an end point of the driving reference line is set.

7. The work vehicle according to any one of claims 1 to 6, comprising the work implement connected to the coupling section.

Images