Work vehicle

Abstract

To enable a vehicle body to travel along a planned travel line even in the presence of positioning errors (positioning accuracy) caused by a positioning device.SOLUTION: A work vehicle comprises: a vehicle body; a joint section; a steering handle; a positioning device which detects a position of the vehicle body; a display device which can display the position of the vehicle body detected with the positioning device and deviations of the positions of the vehicle body detected with an automatic steering mechanism and the positioning device from a planned travel line; and a correction switch to set a correction amount. The automatic steering mechanism can perform automatic steering based on the deviation corrected with the correction amount set by the correction switch. The display device shows a screen for adjusting the correction amount associated with an operation unit of the correction switch.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] Conventionally, Patent Document 1 is known as an agricultural work machine. The agricultural work machine of Patent Document 1 includes a traveling machine body capable of switching between manual traveling by manual steering and automatic traveling along a set traveling line set parallel to a reference traveling line, and a switching switch capable of switching between manual traveling and automatic traveling.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the agricultural work machine of Patent Document 1, since the position of the machine body is detected by GPS or the like to set the reference traveling line, set traveling line, etc., the fact is that the influence of the positioning of the position such as GPS cannot be reduced in the steering, traveling, etc. of the machine body.

[0005] Therefore, in view of the above problems, an object of the present invention is to provide a work vehicle capable of traveling the vehicle body along a planned traveling line even under the influence of a positioning error (positioning accuracy) by a positioning device.

Means for Solving the Problems

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

[0007] The work vehicle includes a travelable vehicle body, a connecting portion capable of connecting a work device for performing work to the vehicle body, a steering wheel 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 travel planned line, a display device capable of displaying a deviation between the vehicle body position detected by the positioning device and the travel planned line, and a correction switch for setting a correction amount. The automatic steering mechanism is capable of automatic steering based on the deviation changed by the correction amount set by the correction switch, and the display device displays a screen for changing the correction amount per operation unit of the correction switch.

[0008] The work vehicle includes 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 operations of the correction switch, and the correction amount per operation unit 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 input to a setting input unit that is displayed on the screen and accepts input of the correction amount per operation unit.

[0010] The work vehicle includes 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 operation amount of the correction switch, and the correction amount per operation unit is the correction amount per a predetermined operation amount of the correction switch.

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

[0012] When the starting point of the driving reference line used for setting the planned driving line is set, the display device displays a first icon on the screen, and when the ending point of the driving reference line is set, the display device displays a second icon on the screen.

[0013] The work vehicle includes the work device connected to the connecting portion.

Advantages 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 the positioning error by the positioning device can be reduced.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 5A

Figure 5B

Figure 6

Figure 7

Figure 8A

Figure 8B

Figure 9A

Figure 9B

Figure 9C

Figure 10

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

[0017] FIG. 10 is a side view showing an embodiment of the work vehicle 1, and FIG. 10 is a plan view showing an embodiment of the work vehicle 1. In 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 or a transplanter, or a construction machine (construction vehicle) such as a loader working machine.

[0018] Hereinafter, the front side (in the direction of arrow A1 in FIG. 10) of the driver sitting in the driver's seat 10 of the tractor (work vehicle) 1 will be described as the front, the rear side (in the direction of arrow A2 in FIG. 10) as the rear, the left side (in the direction of arrow B1 in FIG. 10) as the left, and the right side (in the direction of arrow B2 in FIG. 10) as the right. Also, the horizontal direction (in the direction of arrow B3 in FIG. 10), which is the direction orthogonal to the front-rear direction of the work vehicle 1, will be described as the vehicle body width direction.

[0019] As shown in FIG. 10, the tractor 1 includes a vehicle body 3, a prime mover 4, and a transmission 5. The vehicle 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. Also, the rear wheels 7R may be of a tire type or a crawler type.

[0020] The prime mover 4 is a diesel engine, an electric motor, etc., and in this embodiment, it is composed of a diesel engine. The transmission 5 can switch the driving force of the traveling device 7 by shifting, and can also switch the forward and reverse of the traveling device 7. A driver's seat 10 is provided on the vehicle body 3.

[0021] In addition, a connecting part 8 composed of a three-point link mechanism or the like is provided at the rear part of the vehicle body 3. The working device can be attached to and detached from the connecting part 8. By connecting the working device to the connecting part 8, the vehicle body 3 can tow the working device. The working device includes a tilling device for tilling, a fertilizer spreading device for spreading fertilizers, a pesticide spraying device for spraying pesticides, a harvesting device for harvesting, a mowing device for mowing grass, etc., a spreading device for spreading grass, etc., a grass collecting device for collecting grass, etc., a forming device for forming grass, etc.

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

[0023] Similar to the main transmission part 5b, the auxiliary transmission part 5c has a plurality of gears and a shifter for changing the connection of the gears. The auxiliary transmission part 5c changes and outputs (shifts) the rotation input from the main transmission part 5b by appropriately changing the connection (meshing) of the plurality of 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 or the like, and switches the rotational direction of the shuttle shaft 12, that is, the forward and reverse movement of the tractor 1, by engaging and disengaging the hydraulic clutch. The shuttle shaft 12 is connected to the 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 power from the propulsion shaft 5a can be transmitted thereto. 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 or the like, and switches between a state in which power from the propulsion shaft 5a is transmitted to the PTO propulsion shaft 14 and a state in which power from the propulsion shaft 5a is not transmitted to the PTO propulsion shaft 14 by engaging and disengaging the hydraulic clutch.

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

[0027] The first clutch 17 and the second clutch 18 are constituted by 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 the hydraulic oil discharged from a hydraulic pump 33 is supplied. The first clutch 17 is switched between a connected state and a disconnected state according to 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 a connected state and a disconnected state according to 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 to a connected state or a disconnected state by exciting or demagnetizing the solenoids of the solenoid valves.

[0028] When the first clutch 17 is in the disconnected state and the second clutch 18 is in the connected state, the power of the shuttle shaft 12 is transmitted to the front wheels 7F through the second clutch 18. As a result, four-wheel drive (4WD) in which the front wheels 7F and the rear wheels 7R are driven by power and the rotational 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 the connected state and the second clutch 18 is in the disconnected state, four-wheel drive is achieved and the rotational speed of the front wheels 7F becomes faster than the rotational speed of the rear wheels 7R (4WD speed increasing state). Further, when the first clutch 17 and the second clutch 18 are in the connected state, since the power of the shuttle shaft 12 is not transmitted to the front wheels 7F, two-wheel drive (2WD) in which the rear wheels 7R are driven by power is achieved.

[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, Beidou, Galileo, or QZSS. That is, the positioning device 40 receives a received signal (position of the positioning satellite, transmission time, correction information, etc.) transmitted from the positioning satellite and detects a position (for example, latitude and longitude) based on the received signal. The positioning device 40 has a receiving device 41 and an inertial measurement unit (IMU) 42. The receiving device 41 has an antenna or the like and is a device that receives the received 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 the roll bar provided on the vehicle body 3. Note that the attachment 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, and the like. It is provided below the vehicle body 3, for example, below the driver's seat 10, and the inertial measurement unit 42 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 that steers the vehicle body 3 by the driver's operation and automatic steering that automatically steers the vehicle body 3 without depending on 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 auxiliary mechanism (power steering device) 32. The auxiliary mechanism 32 assists the rotation of the steering shaft 31 (steering handle 30) by hydraulic pressure or the like. The auxiliary mechanism 32 includes a hydraulic pump 33, a control valve 34 to which the hydraulic oil discharged from the hydraulic pump 33 is supplied, and a steering cylinder 35 that is actuated by the control valve 34. The control valve 34 is, for example, a three-position switching valve that can be switched by the movement of a spool or the like, and switches corresponding to 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, if the driver grips the steering handle 30 and operates it in one direction or the other, the switching position and opening degree of the control valve 34 will change corresponding to the rotation direction of the steering handle 30, and the steering cylinder 35 will expand and contract to the left or right according to the switching position and opening degree of the control valve 34, thereby changing the steering direction of the front wheels 7F. That is, the vehicle body 3 can change its traveling direction to the left or right by manually steering the steering handle 30.

[0034] Next, the automatic steering will be described.

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

[0036] Specifically, before automatic steering is performed, the tractor 1 (vehicle body 3) is moved to a predetermined position in the field (S1). When the driver operates the steering changeover switch 52 provided on the tractor 1 at the predetermined position (S2), the vehicle body position measured by the positioning device 40 is set to the starting point P10 of the travel reference line L1 (S3). Further, when the tractor 1 (vehicle body 3) is moved from the starting point P10 of the travel reference line L1 (S4) and the driver operates the steering changeover switch 52 at a predetermined position (S5), the vehicle body position measured by the positioning device 40 is set to the end point P11 of the travel reference line L1 (S6). Therefore, a straight line connecting the starting point P10 and the end point P11 is set as the travel reference line L1.

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

[0038] In addition, after the start of automatic steering, if the driver operates the steering switch 52 at any point, the automatic steering can be terminated. That is, the end point of the planned travel line L2 can be set by terminating the automatic steering by operating the steering switch 52. In other words, the length from the start point to the end point of the planned travel line L2 can be set to be 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 with the planned travel line L2, it is possible to travel while automatically steering a distance longer than the length of the travel reference line L1.

[0039] As shown in FIG. 1, the steering device 11 has an automatic steering mechanism 37. The automatic steering mechanism 37 is a mechanism for automatically steering 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 with the steering shaft 31, and a gear provided on the rotation shaft of the steering motor 38 and rotating with the rotation shaft. When the rotation shaft of the steering motor 38 rotates, the steering shaft 31 automatically rotates (pivots) 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] As shown in FIG. 1, the tractor 1 is provided with a display device 45. The display device 45 is a device capable of displaying various information regarding the tractor 1, and can display at least the 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 at least a setting mode for performing settings before the start of automatic steering. The setting mode is a mode for performing various settings related to the automatic steering before starting the automatic steering. For example, it is a mode for setting the start point and end point of the travel reference line L1 and the like.

[0042] The setting switch 51 can be switched between ON and OFF. 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. Also, 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 the neutral position upward, downward, forward, and backward. When it is switched downward from the neutral position in a state where the setting mode is valid, it outputs the start of automatic steering. When it is switched upward from the neutral position in a state where the setting mode is valid, it outputs the end of automatic steering. Also, when the steering changeover switch 52 is switched backward from the neutral position in a state where the setting mode is valid, it outputs setting the current vehicle body position to the start point P10 of the travel reference line L1. When the steering changeover switch 52 is switched forward from the neutral position in a state where the setting mode is valid, it outputs setting the current vehicle body position to the end point P11 of the travel reference line L1.

[0044] The tractor 1 is provided with a correction switch 53. The correction switch 53 is a switch for correcting the vehicle body position (latitude, longitude) measured by the positioning device 40. That is, the correction switch 53 is a switch for correcting the vehicle body position (referred to as the calculated vehicle body position) calculated from the satellite signal (position of the positioning satellite, transmission time, correction information, etc.) and the measurement information (acceleration, angular velocity) measured by the inertial measurement device 42.

[0045] The correction switch 53 is composed of a push switch that can be pressed or a slide switch that can be slid. Hereinafter, the cases where the correction switch 53 is a push switch and a slide switch respectively will be described.

[0046] When the correction switch 53 is a push switch, the correction amount is set based on the number of operations of the push switch. The correction amount is determined by the formula: correction amount = number of operations × correction amount per operation (correction amount per unit). For example, as shown in FIG. 3A, each time the push switch is operated, the correction amount increases by several centimeters or several tens of centimeters. The number of operations of the push switch is input to the first control device 60A, and the first control device 60A sets (calculates) the correction amount based on the number of operations. Note that the first control device 60A can change a predetermined operation of the push switch, that is, the correction amount per operation. When a predetermined operation is performed on the display device 45, the first control device 60A displays a setting screen for setting the correction amount on the display device 45. On the setting screen, a setting input section for inputting the correction amount per operation (correction amount per unit) of the push switch is displayed. The correction amount per unit of the setting input section can be input by operating the display device 45. The correction amount per unit input to the setting input section of the display device 45 can be stored in the first control device 60A. That is, by inputting the correction amount per unit to the setting input section, for example, the correction amount per unit shown in FIG. 3A can be changed from 2 cm to 4 cm.

[0047] Also, 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 displacement amount from a predetermined position. For example, as shown in FIG. 3B, every time the displacement amount of the slide switch increases by 5 mm, the correction amount increases by several centimeters or several tens of centimeters. The operation amount (displacement amount) of the slide switch is input to the first control device 60A, and the first control device 60A sets (calculates) the correction amount based on the displacement amount. Note that even if the correction switch 53 is a slide switch, the correction amount can be changed in the same manner as a push switch.

[0048] When a predetermined operation is performed on the display device 45, the first control device 60A displays a setting screen for setting the correction amount on the display device 45. On the setting screen, a setting input section for inputting a correction amount (correction amount per unit) for a predetermined operation of the slide switch, that is, the displacement amount of the slide switch, is displayed. The correction amount per unit of the setting input section 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. That is, by inputting the correction amount per unit to the setting input section, for example, as shown in FIG. 3B, the correction amount (correction amount per unit) when the displacement amount increases by 5 mm each time can be changed from 2 cm to 4 cm. Note that the above-described method of increasing the correction amount and the rate of increase are not limited to the above-described numerical values.

[0049] As shown in FIGS. 4A and 4B, the correction switch 53 includes a first correction section 53A and a second correction section 53B. The first correction section 53A is a part that commands correction of a vehicle body position corresponding to one side in the width direction of the vehicle body 3, that is, the left side. The second correction section 53B is a part that commands correction of a vehicle body position corresponding to the other side in the width direction of the vehicle body 3, that is, the right side.

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

[0051] As shown in FIG. 4B, when the correction switch 53 is a slide switch, the first correction part 53A and the second correction part 53B include a knob part 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 part 53A and the second correction part 53B are arranged apart from each other in the width direction. As shown in FIG. 3B, when the knob part 55 is gradually displaced to the left from a predetermined reference position, the left correction amount increases according to the displacement amount. Also, when the knob part 55 is gradually displaced to the right from a predetermined reference position, the right correction amount increases according to the displacement amount. Note that, as shown in FIG. 4B, in the case of a slide switch, the first correction part 53A and the second correction part 53B may be integrally formed, the reference position of the knob part 55 may be set at the center, the left correction amount may be set when moving to the left from the reference position, and the right correction amount may be set when moving the knob part 55 to the right from the intermediate position.

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

[0053] FIG. 5A shows a state where the calculated vehicle body position W1 has shifted to the right during straight-ahead automatic steering. As shown in FIG. 5A, in a state where automatic steering has been started, when the position of the actual tractor 1 (vehicle body 3) (actual position W2) 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 the section P1 where there is no error in the positioning by 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. Incidentally, when there is no error in the positioning by the positioning device 40 and no correction is performed, the calculated vehicle body position W1 and the corrected vehicle body position (corrected vehicle body position) W3 corrected by the correction amount have the same value. The corrected vehicle body position W3 is given by 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, due to various influences, an error occurs in the positioning of the positioning device 40, and the vehicle body position W1 detected by the positioning device 40 is shifted to the right with respect to the planned travel line L2 (actual position W2), and it is assumed that the deviation amount W4 is maintained. Then, 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 shifts to the planned travel line L2 by the left steering. 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. That is, 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 the direction of eliminating the deviation amount W4 generated in the vicinity of position P20. As shown in position P21 of FIG. 5A, when the actual position W2 of the tractor 1 is separated from the planned travel line L2 to the left after the correction of the vehicle body position, 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 when the calculated vehicle body position W1 is shifted to the left during straight travel while the automatic steering is in progress. As shown in FIG. 5B, in a state where the automatic steering is started, when 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, similar to FIG. 5A, the tractor 1 travels along the planned travel line L2. That is, similar to FIG. 5A, in 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, similar to FIG. 5A, the calculated vehicle body position W1 and the corrected vehicle body position W3 have the same value.

[0056] Here, at position P22, due to various influences, an error occurs in the positioning of the positioning device 40, 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 assuming that 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. After that, assuming that the driver notices that the tractor 1 has deviated from the planned travel line L2, and the driver steers the first correction unit 53A at position P23 to increase the left correction amount from zero. Then, a 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. That is, 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 to eliminate the shift amount W5 generated in the vicinity of position P22. As shown at position P23 in FIG. 5B, when the actual position W2 of the tractor 1 is separated from the planned travel line L2 to the right after the correction of the vehicle body position, the tractor 1 is steered to the left, and the actual position W2 of the tractor 1 can be made to coincide with the planned travel line L2.

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

[0058] As shown in FIG. 6, the outer periphery of the steering shaft 31 is covered by the steering post 180. The outer periphery of the steering post 180 is covered by the 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 for supporting the display device 45 is provided on the 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 wheel 30. Further, the upper plate portion 178a has an attachment surface 178f to which the setting switch 51, the correction switch 53, and the screen switching switch 54 are attached. The attachment surface 178f is provided behind the support portion 178e and below the steering wheel 30. The support portion 178e and the attachment surface 178f are continuous. The support portion 178e is located at the front portion of the upper plate portion 178a, and the attachment surface 178f is located at the rear portion of the upper plate portion 178a. The setting switch 51, the correction switch 53, and the screen switching switch 54 are attached to the attachment surface 178f. Thereby, the setting switch 51, the correction switch 53, and the screen switching 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 performs an operation to switch the traveling direction of the vehicle body 3. More specifically, by operating (swinging) the shuttle lever 181 forward, the forward / backward switching unit 13 outputs forward power to the traveling device 7, and the traveling direction of the vehicle body 3 is switched to the forward direction. Further, by operating (swinging) the shuttle lever 181 backward, the forward / backward switching unit 13 outputs backward power to the traveling device 7, and the traveling direction of the vehicle body 3 is switched to the backward 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 handle 30 and covers the periphery of the upper portion of the steering shaft 31. The column cover 179 is formed in a substantially square tube shape and protrudes upward from the mounting surface 178f of the panel cover 178. That is, the mounting surface 178f is provided around the column cover 179. Therefore, the setting switch 51, the correction switch 53, and the screen switching switch 54 attached to the mounting surface 178f are arranged around the column cover 179.

[0062] Next, the arrangements of the setting switch 51, the steering switching switch 52, the correction switch 53, and the screen switching switch 54 will be described in detail. As shown in FIG. 6, the setting switch 51, the steering switching switch 52, the correction switch 53, and the screen switching switch 54 are arranged around the steering shaft 31.

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

[0064] The correction switch 53 is arranged on the other lateral side (right side) of the steering shaft 31. More specifically, the correction switch 53 is arranged on the right side and rear side (diagonally right rear) of the steering shaft 31. In terms of the positional relationship with the column cover 179, the correction switch 53 is arranged on the right side and rear side (diagonally right rear) of the column cover 179. In terms of the positional relationship with the mounting surface 178f of the panel cover 178, the correction switch 53 is arranged at the right rear part of the mounting surface 178f. By arranging the correction switch 53 at the rear part of the inclined mounting surface 178f, the distance between the correction switch 53 and the steering wheel 30 can be ensured to be long. Thereby, the unintentional operation of the correction switch 53 and the steering of the steering wheel 30 can be more reliably prevented.

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

[0066] As described above, the setting switch 51, the steering switching switch 52, the correction switch 53, and the screen switching switch 54 are arranged around the steering shaft 31. In other words, the setting switch 51, the steering switching switch 52, the correction switch 53, and the screen switching switch 54 are concentrated and present around the steering shaft 31. Therefore, the driver can clearly grasp the positions of the respective switches at a glance. In addition, the driver can operate each switch without changing the posture while remaining seated in the driver's seat 10. Therefore, the operability is good and malfunction can be prevented. Also, the harness (wiring) routed from each switch can be shortened.

[0067] Regarding the arrangement of the switches described above, the left and right sides may be swapped. That is, one side may be the left side and the other side may be the right side, or one side may be the right side and the other side may be the left side. 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 includes a plurality of control devices 60. The plurality of control devices 60 are devices that perform control of the traveling system, control of the working system, calculation of the vehicle body position, etc. in the tractor 1. The plurality of control devices 60 are the first control device 60A, the second control device 60B, and the third control device 60C.

[0069] The first control device 60A receives the received 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 obtains the vehicle body position based on the received 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 correct the calculated vehicle body position W1 calculated from the received 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 operations of the correction switch 53 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 by 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 planned 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 so that the vehicle body 3 travels along the planned travel line L2 based on the control signal output from the first control device 60A.

[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 value, 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 value 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 the right direction. When the deviation between the vehicle body position and the planned travel line L2 is equal to or greater than the threshold value 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 the left direction. 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 azimuth of the planned travel line L2 and the azimuth (vehicle body azimuth) F1 of the traveling direction (travel direction) of the tractor 1 (vehicle body 3) are different, that is, when the angle θ between the vehicle body azimuth F1 and the planned travel line L2 is equal to or greater than the threshold value, the second control device 60B may set the steering angle so that the angle θ is zero (the vehicle body azimuth F1 coincides with the azimuth of the planned travel line L2). Further, the second control device 60B may set the final steering angle in the automatic steering based on the steering angle obtained based on the deviation (position deviation) and the steering angle obtained based on the azimuth (azimuth deviation θ). The setting of the steering angle in the 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 an operation of an operation member provided around the driver's seat 10. Note that the first control device 60A, the second control device 60B, and the third control device 60C may be integrated. Further, 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 travel of the vehicle body 3 can be made by the display device 45.

[0074] Hereinafter, the details of the display device 45 will be described.

[0075] As shown in FIG. 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 includes 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, and the like. 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, and the like.

[0076] Further, the display device 45 can acquire information of various switches, for example, information of the setting switch 51, the steering switch 52, and the correction switch 53. The display device 45 can acquire information on ON or OFF of the setting switch 51, information on start and end of automatic steering in the steering switch 52, and information on commands for the start point P10 and the end point P11 of the travel reference line L1 in the steering 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 vary the information to be displayed. The fixed display unit 46A has a panel on which a warning or the like is shown, and an irradiation unit such as an LED that irradiates light to the figure of the panel. Further, the variable display unit 46B is composed of a panel such as an organic EL or a liquid crystal, and displays various information related to the operation (travel) of the tractor 1.

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

[0079] The operation screen M1 has an operation display unit 61 that shows operation information. The operation display unit 61 includes a rotation display unit 62 that displays the rotational speed of the prime mover 4 (prime mover rotational speed) as operation information. The rotation display unit 62 includes a level display unit 63. The level display unit 63 is a part that displays the prime mover rotational speed step by step. For example, the level display unit 63 includes a scale part 65 and an indicator part 80. The scale part 65 has, for example, a first line 65A and a plurality of second lines 65B assigned at predetermined intervals along the first line 65A. Also, the scale part 65 has a third line 65C spaced apart from the first line 65A by a predetermined interval. The first line 65A and the third line 65C are formed, for example, in a semi-circular shape, with one end side (e.g., the left side) being the minimum value and the other end side (e.g., the right side) being the maximum value.

[0080] The indicator part 80 is a bar whose length changes according to the magnitude of the prime mover rotational speed. The indicator part 80 is located, for example, between the first line 65A and the third line 65C. When the value of the prime mover rotational speed is the minimum value of zero, it is located at one end side (the left side) of the first line 65A and the third line 65C and has the shortest length. When the value of the prime mover rotational speed is the maximum value, it extends from one end side (the left side) of the first line 65A and the third line 65C to the other end side (the right side) of the first line 65A and the third line 65C and has the longest length. The rotation display unit 62 includes a digital display unit 64. The digital display unit 64 displays the prime mover rotational speed in numbers. For example, the rotation display unit 62 is arranged inside the semi-circular shape of the first line 65A and the third line 65C.

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

[0082] The operation screen M1 has an icon display unit 67 that displays a plurality of icon units 66. The icon display unit 67 is a part that indicates various information with the icon units 66. That is, settings related to driving such as automatic steering, for example, the set state set in the setting mode is displayed with the icon unit 66. The icon display unit 67 is at a position different from the driving display unit 61 and is arranged, for example, at the upper part of the operation screen M1.

[0083] The plurality of icon units 66 are the first icon unit 66A, the second icon unit 66B, the third icon unit 66C, the fourth icon unit 66D, the fifth icon unit 66E, the sixth icon unit 66F, and the seventh icon unit 66G. Note that the operation screen M1 does not necessarily have all of the plurality of icon units 66 (66A, 66B, 66C, 66D, 66E, 66F, 66G) and is not limited to the above-described embodiment.

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

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

[0086] The fifth icon unit 66E is displayed when the connecting part 8 is in the raising and lowering state. The sixth icon unit 66F is displayed when in the 4WD speed increasing state. The color etc. of the seventh icon unit 66G changes according to the reception sensitivity of the reception signal of the receiving device 41.

[0087] As shown in FIGS. 8A and 8B, the operation screen M1 has a position deviation display section 68. The position deviation display section 68 is a part that stepwise displays the position deviation (displacement amount) between the calculated vehicle body position W1 and the planned travel line L2. 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 horizontally on the operation screen M1 from the origin 68a1. The origin 68a1 indicates a point where the position deviation is zero, and is provided at the longitudinal center of the data line 68a2. The data line 68a2 is a part that indicates the magnitude of the position deviation, and the side opposite to the origin 68a1 is set to the maximum value. In the data line 68a2, the left side (one side) from the origin 68a1 is a region (part) that indicates the position deviation when the vehicle body 3 is displaced to the left side (one side) from the planned travel line L2, and the right side (the other side) from the origin 68a1 is a region (part) that indicates the position deviation when the vehicle body 3 is displaced to the right side (the other side) from the planned travel line L2. Further, auxiliary scales divided into a plurality of steps are shown on the data line 68a2, and it is possible to grasp the magnitude of the position deviation by the indicator section 68b indicating the auxiliary scales.

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

[0089] In this way, in the position deviation display unit 68, 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, the timing of correction by the correction switch 53 and whether correction is performed can be easily grasped. For example, during automatic steering, if a position deviation is shown on the position deviation display unit 68 even though the actual position W2 of the tractor 1 (vehicle body 3) coincides with the planned travel line L2, 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. When the position deviation increases due to the positioning error of the positioning device 40, as described above, by operating the correction switch 53, a correction amount is added 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 above-described embodiment, the position deviation between the calculated vehicle body position W1 and the planned travel line L2 is displayed on the position deviation display unit 68. However, at least after the operation of the correction switch 53, the position deviation between the corrected vehicle body position W3, which is the position deviation after correction by the correction switch 53, and the planned travel line L2 may be displayed. For the sake of convenience in the following description, the position deviation between the calculated vehicle body position W1 and the planned travel line L2 is referred to as "first position deviation W10", and the position deviation between the corrected vehicle body position W3 and the planned travel line L2 is referred to as "second position deviation W11".

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

[0092] FIG. 9A shows a state where, although the actual position W2 of the tractor 1 (vehicle body 3) coincides with the planned travel line L2, a 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. FIG. 9B shows a state where, although a first position deviation W10 has occurred due to the positioning error of the positioning device 40 as in FIG. 9A, a 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 substantially zero, it can be determined that appropriate correction has been performed by the first correction unit 53A. 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 does not become zero and is relatively large, it can be determined that the correction amount by the operation of the first correction unit 53A is small. That is, when 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 can understand that it is necessary to operate the first correction unit 53A to further increase the correction amount. In this case, the driver operates the first correction unit 53A until the second position deviation W11 becomes zero as shown in FIG. 9B. Thus, by displaying the second position deviation W11 on the position deviation display unit 68, it is possible to determine whether the correction amount by the operation of the correction switch 53 is appropriate.

[0093] Further, after the operation of the first correction unit 53A of the correction switch 53, when the second position deviation W11 displayed on the position deviation display unit 68 becomes zero as shown in FIG. 9B and then increases as shown in FIG. 9C after a certain period of time has elapsed, 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 (vehicle body 3) by operating the correction switch 53 to set the correction amount to zero.

[0094] The work vehicle 1 includes a travelable vehicle body 3, a steering wheel 30 that steers the vehicle body 3 by a rotational operation, a positioning device 40 provided on the vehicle body 3 that detects the vehicle body position, which is the position of the vehicle body 3 based on the signals of positioning satellites, a correction switch 53 that commands correction of the vehicle body position detected by the positioning device 40, an automatic steering mechanism 37 that can automatically steer the vehicle body 3 based on the vehicle body position detected by the positioning device 40 and the planned travel line L2, and a display device 45 that can display the position deviation between the vehicle body position detected by the positioning device 40 and the planned travel line L2. According to this, when the vehicle body position can be corrected by the correction switch 53, the display device 45 can display the position deviation between the vehicle body position (calculated vehicle body position) detected by the positioning device 40 and the planned travel line L2. Therefore, when the position deviation between the calculated vehicle body position and the planned travel line L2 is displayed on the display device 45 under the situation where the tractor 1 (vehicle body 3) actually coincides with the planned travel line L2, the driver (operator) can grasp that the position deviation is caused by the positioning error of the positioning device 40. That is, by the driver looking at the position deviation displayed on the display device 45, the influence of the positioning error (positioning accuracy) of the positioning device 40 can be grasped, and when there is a positioning error, the calculated vehicle 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 corrected vehicle body position, which is the vehicle body position corrected by the correction switch 53, and the planned travel line L2. According to this, the position deviation of the planned travel line L2 with respect to the corrected vehicle body position after operating the correction switch 53 can be grasped.

[0096] The correction switch 53 includes a first correction part 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 part 53B that commands correction of the vehicle body position on the other side in the width direction of the vehicle body. According to this, 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 can be easily corrected.

[0097] The work vehicle 1 is provided with a control device 60 to which a correction switch 53 is connected and which controls the automatic steering mechanism 37, and the control device 60 sets a correction amount for the vehicle body position based on the number of operations of the correction switch 53. According to this, the correction amount can be set (changed) according to the number of operations of the correction switch 53.

[0098] The control device 60 changes the correction amount corresponding to each operation of the correction switch 53. According to this, since the correction amount when the correction switch 53 is operated once can be changed, the situation of automatic steering of the vehicle body 3 by operating the correction switch 53 can be changed according to various situations. For example, fine adjustment can be performed in automatic steering by reducing the correction amount when the correction switch 53 is operated once, and rough adjustment of automatic steering can be performed by increasing the correction amount when the correction switch 53 is operated once.

[0099] The control device 60 changes the correction amount per operation amount of the correction switch 53. According to this, since the correction amount when the correction switch 53 is operated by a predetermined amount can be changed, the situation of automatic steering of the vehicle body 3 by operating the correction switch 53 can be changed according to various situations. For example, fine adjustment can be performed in automatic steering by reducing the correction amount when the correction switch 53 is operated by a predetermined amount, and rough adjustment of automatic steering can be performed by increasing the correction amount when the correction switch 53 is operated by a predetermined amount.

[0100] The embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and it is intended that all changes within the meaning and scope equivalent to the claims are included.

[0101] In the above-described embodiment, the display device 45 displayed the position deviation, but it may display the azimuth deviation between the azimuth of the planned travel line L2 and the azimuth (vehicle body azimuth) F1 of the traveling direction (travel direction) of the tractor 1 (vehicle body 3). When displaying the azimuth deviation in the display device 45, the above-described position deviation may be read as the azimuth deviation.

Explanation of Signs

[0102] 1 Work vehicle 3 Vehicle body 30 Steering wheel 37 Automatic steering mechanism 40 Positioning device 45 Display device 53 Correction switch 53A First correction unit 53B Second correction unit 60 Control device L2 Planned travel 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