Work vehicle

Abstract

To enable stable automatic steering.SOLUTION: A work vehicle includes: a steering wheel; a vehicle body capable of travelling with either manual steering by the steering wheel or automatic steering of the steering wheel on the basis of a travel reference line; and a display device including a line azimuth display part indicating an azimuth of the travel reference line and a vehicle body azimuth display part indicating an azimuth of the vehicle body.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a work vehicle, 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 body capable of switching between manual traveling by manual steering and automatic traveling by automatic steering 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. Further, when the right instruction button is pressed during traveling along the ridge, the starting point of the reference traveling line is set, and the end point of the reference traveling line is set by pressing the left instruction button during traveling. That is, the reference traveling line is set before automatic steering.

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, automatic traveling can be easily performed by switching from manual traveling to automatic traveling with a switching switch. In automatic traveling, since the agricultural work machine travels along a reference traveling line, it is often the case that just before automatic traveling, the azimuth of the traveling direction of the agricultural work machine and the azimuth of the reference traveling line coincide. If the azimuths of the two are greatly deviated, the behavior of the agricultural work machine during initial traveling may not be stable.

[0005] Therefore, in view of the above problems, an object of the present invention is to provide a work vehicle capable of stably performing automatic steering.

Means for Solving the Problems

[0006] The technical means of the present invention for solving this technical problem are characterized by the following points. The work vehicle includes a steering device having a steering wheel, a vehicle body capable of traveling by either manual steering by the steering wheel or automatic steering of the steering wheel based on a travel reference line, a positioning device capable of detecting the orientation of the vehicle body, a display device having a line orientation display section indicating the orientation of the travel reference line, and a vehicle body orientation display section indicating the orientation of the vehicle body, a control device that permits the automatic steering when the orientation difference, which is the difference between the orientation of the vehicle body detected by the positioning device and the orientation of the travel reference line, is within a determination range and performs automatic steering by the steering device when the permission is given, and an inclination detection device that detects the inclination in the width direction of the vehicle body. The display device displays the orientation for permitting the automatic steering as a deviation of the vehicle body orientation display section with respect to the travel reference line. The control device determines whether to permit the automatic steering according to the inclination in the width direction of the vehicle body detected by the inclination detection device. When it is determined that the automatic steering is permitted according to the inclination in the width direction of the vehicle body, the display device displays that the automatic steering is possible. The determination range is a case where the inclination in the width direction of the vehicle body is zero, and with a reference line where the orientation of the vehicle body and the orientation of the travel reference line coincide as the center, the absolute values of the lower limit value on one side and the upper limit value on the other side are the same value, and it is a range from the lower limit value to the upper limit value with the reference line as the center. The control device determines whether to permit the automatic steering based on the determination range. The display device displays that the automatic steering is possible when the orientation difference is within the determination range, and displays that the automatic steering is impossible when the orientation difference is outside the determination range.

[0007] The line orientation display section includes a line display section indicating the travel reference line and a mark section indicating that it is the orientation of the travel reference line. The vehicle body orientation display section includes an orientation pointer section indicating the orientation of the vehicle body and a vehicle body display section indicating the vehicle body whose display position is changed according to the orientation of the vehicle body.

[0008] The vehicle body orientation display unit has different display forms when the orientation difference between the orientation of the driving reference line and the orientation of the vehicle body is within a predetermined range and when the orientation difference is outside the predetermined range.

Advantages of the Invention

[0009] According to the present invention, automatic steering can be stably performed.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 5A

Figure 5B

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10A

Figure 10B

Figure 10C

Figure 10D

Figure 11

Figure 12

Figure 13A

Figure 13B

Figure 13C

Figure 14A

Figure 14B

Figure 15

Figure 16

Mode for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 16 is a side view showing an embodiment of the work vehicle 1, and FIG. 16 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.

[0012] Hereinafter, with reference to the driver sitting in the driver's seat 10 of the tractor (work vehicle) 1, the front side of the driver (in the direction of arrow A1 in FIG. 16) is defined as the front, the rear side of the driver (in the direction of arrow A2 in FIG. 16) is defined as the rear, the left side of the driver is defined as the left, and the right side of the driver is defined as the right. Also, the horizontal direction, which is perpendicular to the front-rear direction of the work vehicle 1, is defined as the vehicle body width direction. As shown in FIG. 16, 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 the tire type or the crawler type. Also, the rear wheels 7R may be of the tire type or the crawler type.

[0013] 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 gears and can also switch between forward and reverse of the traveling device 7. A driver's seat 10 is provided on the vehicle body 3. In addition, a connecting portion 8 composed of a three-point link mechanism or the like is provided at the rear of the vehicle body 3. A work device can be detachably attached to the connecting portion 8. By connecting the work device to the connecting portion 8, the vehicle body 3 can tow the work device. The work device includes a tilling device for tilling, a fertilizer spreading device for spreading fertilizer, 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.

[0014] As shown in FIG. 1, the transmission 5 includes a main shaft (propulsion shaft) 5a, a main transmission section 5b, an auxiliary transmission section 5c, a shuttle section 5d, a PTO power transmission section 5e, and a front transmission section 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 section 5b has a plurality of gears and a shifter for changing the connection of the gears. The main transmission section 5b changes (shifts) the rotation input from the propulsion shaft 5a by appropriately changing the connection (meshing) of the plurality of gears with the shifter and outputs it.

[0015] Similar to the main transmission section 5b, the auxiliary transmission section 5c has a plurality of gears and a shifter for changing the connection of the gears. The auxiliary transmission section 5c changes (shifts) the rotation input from the main transmission section 5b by appropriately changing the connection (meshing) of the plurality of gears with the shifter and outputs it. The shuttle section 5d has a shuttle shaft 12 and a forward / reverse switching section 13. Power output from the auxiliary transmission section 5c is transmitted to the shuttle shaft 12 via gears and the like. The forward / reverse switching section 13 is composed of, for example, a hydraulic clutch or the like, and switches the rotation direction of the shuttle shaft 12, that is, the forward and reverse 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 the rear axle 21R to which the rear wheels 7R are attached.

[0016] 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 the PTO shaft 16 via gears and the like. The PTO clutch 15 is composed of, for example, a hydraulic clutch or the like, and by engaging and disengaging the hydraulic clutch, it switches between a state where the power of the propulsion shaft 5a is transmitted to the PTO propulsion shaft 14 and a state where the power of the propulsion shaft 5a is not transmitted to the PTO propulsion shaft 14. not transmitted to the PTO propulsion shaft 14.

[0017] The front transmission section 5f has a first clutch 17 and a second clutch 18. The first clutch 17 and the second clutch are capable of transmitting the power from the propulsion shaft 5a. For example, the power of the shuttle shaft 12 is transmitted via gears and transmission shafts. The 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 the front axle 21F to which the front wheels 7F are attached.

[0018] 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 the hydraulic pump 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 solenoid of the solenoid valve.

[0019] 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, it is four-wheel drive (4WD) in which the front wheels and the rear wheels are driven by power and the rotational speeds of the front wheels and the rear wheels 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, it becomes four-wheel drive and the rotational speed of the front wheels becomes faster than the rotational speed of the rear wheels (4WD speed increasing state). Further, when the first clutch 17 and the second clutch 18 are in the disconnected state, the power of the shuttle shaft 12 is not transmitted to the front wheels 7F, so it becomes two-wheel drive (2WD) in which the rear wheels are driven by power.

[0020] The tractor 1 is equipped with a positioning device 40. The positioning device 40 can detect 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 satellite signals (position of the positioning satellite, transmission time, correction information, etc.) transmitted from the positioning satellite and detects the position (for example, latitude and longitude) based on the satellite signals. The positioning device 40 has a receiving device 41 and an inertial measurement unit (IMU) 42. The receiv ing device 41 is a device that has an antenna or the like and receives satellite signals 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 ROPS provided on the vehicle body 3. Note that the attachment location of the receiving device 41 is not limited to the embodiment.

[0021] 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. As shown in FIG. 1, the tractor 1 is equipped with a steering device 11. The steering device 11 is a device that can perform manual steering for steering the vehicle body 3 by the driver's operation and automatic steering for automatically steering the vehicle body 3 without depending on the driver's operation.

[0022] The steering device 11 has a steering wheel 30 and a steering shaft (rotating shaft) 31 that rotatably supports the steering wheel 30. Further, the steering device 11 has an auxiliary mechanism (power steering device) 32. The auxiliary mechanism 32 assists the rotation of the steering shaft 31 (steering wheel 30) by hydraulic pressure or the like. The auxiliary mechanism 32 has a hydraulic pump 33 and the working fluid discharged from the hydraulic pump 33 It includes a control valve 34 to which oil is supplied and a steering cylinder 35 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 is switched 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 wheel 7F.

[0023] Therefore, if the driver grips the steering wheel 30 and operates it in one direction or the other, the switching position and opening degree of the control valve 34 are switched corresponding to the rotation direction of the steering wheel 30, and the steering cylinder 35 expands and contracts to the left or right according to the switching position and opening degree of the control valve 34, whereby the steering direction of the front wheel 7F can be changed. That is, the vehicle body 3 can change its traveling direction to the left or right by manually steering the steering wheel 30.

[0024] Next, the automatic steering will be described. 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.

[0025] 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.

[0026] 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.

[0027] Also, after the start of automatic steering, if the driver operates the steering switch 52 at any position, 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.

[0028] As shown in FIG. 1, the steering device 11 has an automatic steering mechanism 37. The automatic steering mechanism 3 7 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.

[0029] As shown in FIG. 1, the tractor 1 includes a display device 45. The display device 45 is a device capable of displaying various information related to the tractor 1, and can at least display the driving information of the tractor 1. The display device 45 is provided in front of the driver's seat 10. As shown in FIG. 1, the tractor 1 is provided with a setting switch 51. The setting switch 51 is a switch that switches 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.

[0030] 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.

[0031] 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. That is, the steering changeover switch 52 also serves as a reference line setting switch for setting the start position (start point P10) and end position (end point P11) of the travel reference line L1. Note that the steering changeover switch 52 for switching the start or end of automatic steering and the reference line setting switch may be configured separately.

[0032] The tractor 1 is equipped 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.

[0033] The correction switch 53 is composed of a pushable push switch or a slidable slide switch. Hereinafter, the cases where the correction switch 53 is a push switch and a slide switch respectively will be described. 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. For example, as shown in Fig. 3A, each time the push switch is operated the correction amount increases by several centimeters or dozens 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.

[0034] 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 formula: correction amount = displacement amount from a predetermined position. For example, as shown in Fig. 3B, each time the displacement amount of the slide switch increases by 5 mm, the correction amount increases by several centimeters or dozens 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 the above-described method of increasing the correction amount and the rate of increase are not limited to the above-described numerical values.

[0035] Specifically, as shown in FIGS. 4A and 4B, the correction switch 53 has a first correction part 53A and a second correction part 53B. The first correction part 53A is a part that commands correction of the vehicle body position corresponding to one side in the width direction of the vehicle body 3, that is, the left side. The second correction part 53B is a part that commands correction of the vehicle body position corresponding to the other side in the width direction of the vehicle body 3, that is, the right side.

[0036] 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 separately from each other. As shown in FIG. 3A, every time the first correction part 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 part 53B is pressed, the correction amount (right correction amount) corresponding to the right side of the vehicle body 3 increases.

[0037] 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 separately 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 central part, 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.

[0038] 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. Figure 5A shows the state when the calculated vehicle body position W1 deviates to the right during straight travel while automatic steering is in progress. As shown in Figure 5A, in the state where automatic steering has 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. 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 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.

[0039] 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.

[0040] FIG. 5B shows a state where the calculated vehicle body position W1 is shifted to the left during straight travel while automatic steering is in progress. As shown in FIG. 5B, in a state where automatic steering has been 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, the tractor 1 travels along the planned travel line L2 in the same manner as in FIG. 5A. That is, in the same manner as in 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, in the same manner as in FIG. 5A, the calculated vehicle body position W1 and the corrected vehicle body position W3 have the same value.

[0041] 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 is 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 the 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.

[0042] Next, the setting switch 51 and the correction switch 53 will be described. 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.

[0043] 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 includes the setting switch 51 and the correction switch It has an attachment surface 178f to which 53 is 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 of the upper plate portion 178a, and the attachment surface 178f is located at the rear of the upper plate portion 178a. The setting switch 51 and the correction switch 53 are attached to the attachment surface 178f. Thereby, the setting switch 51 and the correction switch 53 are arranged around the steering shaft 31.

[0044] 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-reverse 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. Also, by operating (swinging) the shuttle lever 181 backward, the forward-reverse switching unit 13 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.

[0045] The column cover 179 is arranged 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 square tube shape and protrudes upward from the attachment surface 178f of the panel cover 178. That is, the attachment surface 178f is provided around the column cover 179. Therefore, the setting switch 51 and the correction switch 53 attached to the attachment surface 178f are arranged around the column cover 179.

[0046] Next, the respective arrangements of the setting switch 51, the steering changeover switch 52, and the correction switch 53 will be described in detail. As shown in FIG. 6, the setting switch 51, the steering changeover switch 52, and the correction switch 53 are arranged around the steering shaft 31. The setting switch 51 is arranged on one side (left side) of the steering shaft 31. The steering mode switching switch 52 is arranged on one side (left side) of the steering shaft 31. In the case of this embodiment, the steering mode switching switch 52 is composed of a swingable lever. The steering mode switching switch 52 is swingable with the base end provided on the steering shaft 31 side as a fulcrum. The base end of the steering mode switching switch 52 is provided inside the column cover 179. The steering mode switching switch 52 protrudes from one side (left side) of the column cover 179.

[0047] The correction switch 53 is arranged on the other 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.

[0048] As described above, the setting switch 51, the steering mode switching switch 52, and the correction switch 53 are arranged around the steering shaft 31. In other words, the setting switch 51, the steering mode switching switch 52, and the correction switch 53 exist in a concentrated manner 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 the malfunction can be prevented. Moreover, the harness (wiring) routed from each switch can be shortened.

[0049] 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.

[0050] 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 a first control device 60A, a second control device 60B, and a third control device 60C. The first control device 60A receives the satellite 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.

[0051] The first control device 60A sets a control signal based on the vehicle body position (the calculated vehicle body position W1 and the 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 has an automatic steering control unit 200. The automatic steering control unit 200 is composed of an electric / electronic circuit provided in the second control device 60B, a program stored in a CPU, etc. The automatic steering control unit 200 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.

[0052] 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 automatic steering control unit 200 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 greater than or equal to the threshold value and the tractor 1 is located on the left side of the planned travel line L2, the automatic steering control unit 200 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 greater than or equal to the threshold value and the tractor 1 is located on the right side of the planned travel line L2, the automatic steering control unit 200 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 was 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 (traveling direction) of the tractor 1 (vehicle body 3) are different, that is, when the angle θg between the vehicle body azimuth F1 and the planned travel line L2 is greater than or equal to the threshold value, the automatic steering control unit 200 may set the steering angle so that the angle θg is zero (the vehicle body azimuth F1 coincides with the azimuth of the planned travel line L2). Further, the automatic steering control unit 200 may set the final steering angle in 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). The setting of the steering angle in the automatic steering in the above-described embodiment is an example and is not limited.

[0053] 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 6 0C may be integrated. Also, 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. Now, after setting the traveling reference line L1, in order to perform automatic steering, it is necessary to adjust the conditions for automatic steering. For example, as shown in FIG. 8, after the tractor 1 has turned and before automatic steering, when the azimuth (vehicle body azimuth) F1 of the traveling direction of the tractor 1 and the azimuth (line azimuth) F2 of the traveling reference line L1 are significantly different, even if automatic steering is started, it is difficult to steer the tractor 1 along the planned traveling line L2 parallel to the traveling reference line L1. In such a case, the second control device 60B determines that the conditions for automatic steering are not met.

[0054] The second control device 60B makes a determination (judgment) as to whether to permit automatic steering based on at least the vehicle body azimuth F1 of the tractor 1 (vehicle body 3) during manual steering, that is, before automatic steering, and the azimuth (line azimuth) F2 of the traveling reference line L1. As shown in FIG. 1, the second control device 60B includes an azimuth determination unit 207. The azimuth determination unit 207 is composed of an electric / electronic circuit provided in the second control device 60B, a program stored in a CPU, etc. The azimuth determination unit 207 permits automatic steering if the azimuth difference ΔF between the vehicle body azimuth F1 and the line azimuth F2 is within the determination range G1, and does not permit automatic steering if it is outside the determination range G1.

[0055] FIG. 9 is a diagram showing the relationship between the azimuth difference ΔF and the determination range G1. As shown in FIG. 9, the determination range G1 is a range indicated with a minus sign on one side (left side) and a plus sign on the other side (right side) centered on the reference line 210 where the vehicle body azimuth F1 and the line azimuth F2 coincide (the reference line 210 where the azimuth difference ΔF is zero). The lower limit value Gmin of the determination range G1 is on the minus side, and the upper limit value Gmax is on the plus side. Note that the plus and minus signs in the determination range G1 in FIG. 9 are set for convenience and are not limited to the above example.

[0056] When the lateral inclination of the vehicle body 3 of the tractor 1, that is, the roll angle of the vehicle body 3 is horizontal and the inclination is zero (on a flat ground), the lower limit value Gmin and the upper limit value Gmax of the determination range G1 are predetermined values. Considering the lower limit value Gmin and the upper limit value Gmax as absolute values, the two are of the same value. Therefore, when the tractor 1 is traveling while maintaining a horizontal state without tilting in the lateral direction, that is, when traveling on a field without inclination, if the azimuth difference ΔF between the vehicle body azimuth F1 and the line azimuth F2 falls within the determination range G1, the azimuth determination unit 207 permits automatic steering. If the azimuth difference ΔF falls outside the determination range G1, automatic steering is not permitted.

[0057] In the above-described embodiment, the second control device 60B determines whether to permit automatic steering based on the azimuth difference ΔF and the determination range G1. In addition to this, when the tractor 1 (vehicle body 3) is traveling while tilted, the second control device 60B changes the determination range G1 used for automatic steering according to the inclination of the vehicle body 3. The inclination of the vehicle body 3 is detected by an inclination detection device provided on the tractor 1 (vehicle body 3). In this embodiment, the inclination detection device is, for example, an inertial measurement device 42 having an acceleration sensor for detecting acceleration, a gyro sensor for detecting angular velocity, etc., and can detect the tractor 1 (vehicle body 3). Note that the inclination detection device may be a device composed of a plurality of positioning devices 40 (for example, a GPS compass, etc.), or other devices.

[0058] As described above, when the lateral inclination of the vehicle body 3 of the tractor 1, that is, the roll angle of the vehicle body 3 is horizontal and the inclination is zero, as shown in FIG. 9, the azimuth determination unit 207 sets the determination range G1 to the standard range ST1 and determines whether to permit automatic steering based on the standard range ST1. As shown in FIG. 10A, when the tractor 1 (vehicle body 3) is tilted such that one side (left side) in the lateral direction of the tractor 1 (vehicle body 3) is higher than the other side (right side) in the lateral direction, the second control device 60B sets the lower limit value Gmin of the determination range G1 to the lower limit value Gmin indicated by the standard range ST1 Make it larger. That is, when looking at the travel reference line L1 from the tractor 1, if the travel reference line L1 is high and the tractor 1 side is low and slopes downward to the right, the lower limit value Gmin of the determination range G1 is increased. In this case, the azimuth determination unit 207 determines whether to permit automatic steering based on the determination range G1 with the increased lower limit value Gmin.

[0059] As shown in FIG. 10A, when the tractor 1 is inclined downward to the right, when looking at the range of the determination range G1, the lower limit value Gmin corresponding to the high side (one side) of the tractor 1 is increased. In addition to this, as shown in FIG. 10C, it is preferable that the upper limit value Gmax on the side opposite to the lower limit value Gmin of the determination range G1 is made smaller than the upper limit value Gmax of the standard range ST1. In other words, when the tractor 1 is inclined downward to the right, the upper limit value Gmax corresponding to the low side (the other side) of the tractor 1 is decreased.

[0060] As shown in FIG. 10B, when the tractor 1 (the vehicle body 3) is inclined such that one side (the left side) is lower than the other side (the right side) in the width direction, the second control device 60B makes the upper limit value Gmax of the determination range G1 larger than the upper limit value Gmax indicated by the standard range ST1. That is, when looking at the travel reference line L1 from the tractor 1, if the travel reference line L1 is high and the tractor 1 side is low and slopes downward to the left, the upper limit value Gmax of the determination range G1 is increased. In this case, the azimuth determination unit 207 determines whether to permit automatic steering based on the determination range G1 with the increased upper limit value Gmax.

[0061] As shown in FIG. 10B, when the tractor 1 is inclined downward to the left, when looking at the range of the determination range G1, the upper limit value Gmax corresponding to the high side (the right side) of the tractor 1 is increased. In addition to this, as shown in FIG. 10D, it is preferable that the lower limit value Gmin on the side opposite to the upper limit value Gmax of the determination range G1 is made smaller than the lower limit value Gmin of the standard range ST1. In other words, when the tractor 1 is inclined downward to the left, the lower limit value Gmin corresponding to the low side (one side) of the tractor 1 is decreased.

[0062] In addition, when changing the lower limit value Gmin and the upper limit value Gmax of the determination range G1, the second control device 60B increases the lower limit value Gmin and the upper limit value Gmax according to the magnitude (tilt amount) of the inclination in the width direction of the vehicle body 3 of the tractor 1 (roll angle of the vehicle body 3). That is, when the tilt amount is large, the second control device 60B increases the increase amounts of the lower limit value Gmin and the upper limit value Gmax with respect to the standard range ST1, and when the tilt amount is small, the second control device 60B decreases the increase amounts of the lower limit value Gmin and the upper limit value Gmax with respect to the standard range ST1.

[0063] When the automatic steering control unit 200 is switched to start automatic steering by the steering changeover switch 52 in a state determined to be permitted by the azimuth determination unit 207, the automatic steering is performed by controlling the steering device 11 as described above. The display device 45 can display that the start of automatic steering is determined to be permitted by the azimuth determination unit 207. As shown in FIG. 11, when a predetermined operation is performed on the display device 45, the display device 45 displays the operation screen M1.

[0064] 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 rotation speed of the prime mover 4 (prime mover rotation 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 rotation 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. Further, 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 in a semicircular shape, for example, 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.

[0065] The indicator unit 80 is a bar whose length changes according to the magnitude of the prime mover rotational speed. The indicator unit 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 (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 (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 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 - circles of the first line 65A and the third line 65C.

[0066] 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 can be displayed in numbers by the rotation display unit 62. The operation screen M1 has an icon display unit 67 that displays a plurality of icon parts 66. The icon display unit 67 is a part that indicates various information with the icon parts 66. That is, settings related to running such as automatic steering, for example, the set state set in the setting mode is displayed with the icon parts 66. The icon display unit 67 is at a position different from the operation display unit 61 and is arranged, for example, at the upper part of the operation screen M1.

[0067] The plurality of icon parts 66 are the first icon part 66A, the second icon part 66B, the third icon part 66C, the fourth icon part 66D, the fifth icon part 66E, the sixth icon part 66F, and the seventh icon part 66G. Note that the operation screen M1 does not necessarily have all of the plurality of icon parts 66 (66A, 66B, 66C, 66D, 66E, 66F, 66G) and is not limited to the above - described embodiment.

[0068] The first icon part 66A is displayed when a warning occurs. The second icon part 66B is displayed when the starting point P10 of the travel reference line L1 is set. The third icon part 66C is displayed when the end point P11 of the travel reference line L1 is set. 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 viewing 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.

[0069] 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 the 4WD speed increase state is present. The color etc. of the seventh icon unit 66G changes according to the reception sensitivity of the reception signal of the receiving device 41. In the above-described embodiment, as a condition for permitting automatic steering, it is conditioned that the azimuth difference ΔF is within a predetermined range, but it may be added as a condition that the steering angle of the steering device 11 is within a predetermined range. That is, in a situation where the tractor 1 (vehicle body 3) is manually steered, the second control device 60B permits automatic steering regarding the azimuth (first permission) when the azimuth difference ΔF is within a predetermined range, and permits automatic steering regarding the steering (second permission) when the steering angle θ of the steering device 11 is within a predetermined range. Then, the second control device 60B starts automatic steering when the first permission and the second permission are both satisfied and the switching of the start of automatic steering is performed by the operator.

[0070] The work vehicle 1 includes a steering device 11 having a steering wheel 30, a vehicle body 3 capable of traveling either by manual steering with the steering wheel 30 or by automatic steering of the steering wheel 30 based on the travel reference line L1, a positioning device 40 capable of detecting the azimuth F1 of the vehicle body 3, an inclination detection device for detecting the inclination of the vehicle body 3, and the azimuth F1 of the vehicle body 3 detected by the positioning device 40 When the difference ΔF from the running reference line L1 and the azimuth F2 is within the determination range G1, a control device 60B that permits automatic steering and, when permitted, performs automatic steering by the steering device 11 is provided. The control device 60B changes the determination range according to the inclination of the vehicle body 3 detected by the inclination detection device. According to this, for example, when the work vehicle 1 (vehicle body 3) is working on a sloping ground, in either case where the work vehicle 1 faces the traveling direction in the uphill direction (when the vehicle body azimuth faces the uphill direction) and where the work vehicle 1 faces the traveling direction in the downhill direction (when the vehicle body azimuth faces the downhill direction), the start of automatic steering can be appropriately performed corresponding to the inclination. That is, even on a sloping ground, when switching from manual steering to automatic steering, it runs stably.

[0071] When the vehicle body 3 is inclined such that one side in the width direction of the vehicle body 3 is higher than the other side in the width direction, the control device 60B changes the lower limit value Gmin of the determination range G1 according to the inclination of the vehicle body 3. Further, when the vehicle body 3 is inclined such that one side in the width direction of the vehicle body 3 is lower than the other side in the width direction, the control device 60B changes the upper limit value Gmax of the determination range G1 according to the inclination of the vehicle body 3.

[0072] According to this, when the work vehicle 1 (vehicle body 3) is traveling on a sloping ground, the lower limit value Gmin corresponding to the higher side (one side) of the tractor 1 can be increased, or the upper limit value Gmax corresponding to the higher side (the other side) of the tractor 1 can be increased. That is, in the determination range G1, the values (upper limit value Gmax, lower limit value Gmin) on the higher side of the work vehicle 1 (vehicle body 3) become larger. As a result, when the work vehicle 1 is manually steered to the higher side and then automatic steering is performed (when the tractor 1 is manually steered in the uphill direction and then automatic steering is performed), it becomes possible to switch to automatic steering after increasing the azimuth difference between the vehicle body azimuth and the line azimuth. In this way, when the work vehicle 1 starts automatic steering in the uphill direction, on a sloping ground, the running immediately after the switch to automatic steering can be stably performed.

[0073] Further, as shown in FIG. 10C, when the tractor 1 is inclined such that the other side (right side) of the tractor 1 is lower than the one side (left side), the control device 60B makes the upper limit value Gmax corresponding to the other side (right side) smaller than a predetermined standard range ST1. Further, as shown in FIG. 10D, when the tractor 1 is inclined such that the one side (left side) of the tractor 1 is lower than the other side (right side), the control device 60B makes the lower limit value Gmin corresponding to the one side (left side) smaller than a predetermined standard range ST1.

[0074] According to this, when the work vehicle 1 is manually steered to the lower side and then automatic steering is performed (when automatic steering is performed after manually steering the tractor 1 in the downward direction), it becomes possible to switch to automatic steering after reducing the azimuth difference between the vehicle body azimuth and the line azimuth. Thus, when the work vehicle 1 starts automatic steering in the downward direction, it is possible to stably perform traveling immediately after switching to automatic steering on a sloping ground.

[0075] The work vehicle 1 includes a steering switch 52 for switching either the start or end of automatic steering, and the control device 60B starts automatic steering by the steering device 11 when the start of automatic steering is switched by the steering switch 52 in a state where automatic steering is permitted. According to this, an operator can issue a command for starting the automatic steering by the steering switch 52 at a timing when the operator wants to start the automatic steering.

[0076] The work vehicle 1 includes a display device 45 that displays that the azimuth difference ΔF between the azimuth of the vehicle body 3 detected by the positioning device 40 and the azimuth F2 of the traveling reference line L1 is within the determination range G1. According to this, an operator can easily grasp that it is in a state where automatic steering can be started by looking at the display device 45. The work vehicle 1 includes a reference line setting switch for setting the position of the vehicle body 3 detected by the positioning device 40 to the start position and the end position of the traveling reference line L1. According to this, it is possible to easily set the traveling reference line L1.

[0077] ​ Now, the display device 45 can display the line direction F2 of the travel reference line L1 and the vehicle body direction F1. As shown in FIG. 12, when a predetermined operation is performed on the display device 45, the display device 45 displays an orientation screen M2. The orientation screen M2 includes a line direction display unit 130 and a vehicle body direction display unit 140. The line direction display unit 130 is a part that shows the line direction F2 of the travel reference line L1, and includes a line display unit 130a and a mark unit 130b. The line display unit 130a is a part that shows the travel reference line L1 itself in a diagram or the like, and extends from the lower side to the upper side on the field 133 set on the orientation screen M2. The mark unit 130b is a part that indicates that it is the direction of the travel reference line L1. For example, in the field 133, it is arranged above the end 131 of the line display unit 130a. In the mark unit 130b, the apex 132 of the triangle indicates the end 131 of the line display unit 130a.

[0078] The vehicle body direction display unit 140 includes an orientation pointer unit 141 that indicates the direction of the vehicle body 3 (vehicle body direction F1). The orientation pointer unit 141 indicates the direction in which the vehicle body direction F1 faces with respect to the line direction F2. The orientation pointer unit 141 is constituted by a figure such as an arrow, for example, and the orientation pointer unit 141 moves to one side or the other side of the line display unit 130a around the origin O1 set on the line of the line display unit 130a.

[0079] In addition, the vehicle body direction display unit 140 includes a vehicle body display unit 142 that shows the tractor 1 (vehicle body 3) in a figure. The vehicle body display unit 142 changes its position (display position) according to the orientation around the origin O1 in the same manner as the orientation pointer unit 141. Specifically, the orientation pointer unit 141 is arranged at the front part of the vehicle body display unit 142 (the front part of the tractor 1), and the vehicle body display unit 142 and the orientation pointer unit 141 swing simultaneously according to the vehicle body direction F1.

[0080] As shown in FIG. 13A, when the vehicle body orientation F1 is in the same direction as the line orientation F2, the tip 141a of the orientation pointer portion 141 faces the end 131 of the mark portion 130b. Further, as shown in FIG. 13B, when the vehicle body orientation F1 is shifted to the left with respect to the line orientation F2, the tip 141a of the orientation pointer portion 141 is located to the left of the line display portion 130a. As shown in FIG. 13C, when the vehicle body orientation F1 is shifted to the right with respect to the line orientation F2, the tip 141a of the orientation pointer portion 141 is located to the right of the line display portion 130a.

[0081] According to the above, by checking the relative position between the tip 141a of the orientation pointer portion 141 and the mark portion 130b or the line display portion 130a, the operator can grasp how much the vehicle body orientation F1 is deviated from the line orientation F2. Note that, as shown in FIG. 12, an orientation scale portion 145 may be displayed on the orientation screen M2. The orientation scale portion 145 is a scale in which the line orientation F2 of the traveling reference line L1 is used as a reference point O2, and the orientation difference ΔF (a value indicating an orientation) increases or decreases according to the distance from the reference point O2. That is, the orientation scale portion 145 is semi-circular, and scale lines 145a corresponding to the orientation difference ΔF are assigned at predetermined intervals along the circumference of the semi-circle. The end 131 of the mark portion 130b is pointed to the reference point O2 of the orientation scale portion 145. Further, as shown in FIG. 15, a determination range G1 is shown in the orientation scale portion 145. That is, at least two colors are separately colored on the plurality of scale lines 145a of the orientation scale portion 145, and a color (in-range color) indicating that the value is within the determination range G1 is colored on the plurality of scale lines 145a closer to the reference point O2, and a color (out-of-range color) indicating that the value is outside the determination range G1 is colored on the plurality of scale lines 145a at a position away from the reference point O2. Further, as described above, when the determination range G1 is changed according to the inclination of the vehicle body 3, the in-range color and the out-of-range color of the plurality of scale lines 145a are changed so as to correspond to the changed determination range G1.

[0082] The azimuth pointer section 141 is disposed inside (on the inner diameter side) of the azimuth scale section 145 and indicates the vehicle body azimuth F1 to the azimuth scale section 145. The display form of the azimuth pointer section 141 is different when the azimuth difference ΔF between the line azimuth F2 and the vehicle body azimuth F1 is within a predetermined range (within the determination range G1) and when the azimuth difference ΔF is outside the predetermined range (outside the determination range G1). As shown in FIGS. 13A to 13C, when the azimuth difference ΔF is within the predetermined range (within the determination range G1), the azimuth pointer section 141 is colored the same color as the color within the range of the azimuth scale section 145. Further, as shown in FIGS. 14A and 14B, when the azimuth difference ΔF is outside the predetermined range (outside the determination range G1), the azimuth pointer section 141 is colored the same color as the color outside the range of the azimuth scale section 145.

[0083] Also, when the azimuth difference ΔF is within the predetermined range, the display device 45 displays a handle display section 68 that graphically shows the steering wheel 30 on the azimuth screen M2, and also displays a graphic 143 indicating that automatic steering can be started. The work vehicle 1 includes a steering wheel 30, a vehicle body 3 that can travel by either manual steering with the steering wheel 30 or automatic steering of the steering wheel 30 based on the travel reference line L1, a line azimuth display section 130 that indicates the azimuth F2 of the travel reference line L1, and a vehicle body azimuth display section 140 that indicates the azimuth F1 of the vehicle body 3, and a display device 45. According to this, the display device 45 can easily grasp in which direction the azimuth of the work vehicle 1 (vehicle body 3) is with respect to the azimuth F2 of the travel reference line L1.

[0084] The line azimuth display section 130 includes a line display section 130a that indicates the travel reference line L1 and a mark section 130b that indicates that the azimuth is F2 of the travel reference line L1. According to this, even if the operator cannot accurately grasp in which direction the azimuth F2 of the travel reference line L1 is in a work site such as a field, by looking at the line display section 130a and the mark section 130b displayed on the display device 45, the azimuth F2 of the travel reference line L1 can be easily grasped.

[0085] The vehicle body orientation display unit 140 includes an orientation pointer unit 141 that indicates the orientation F1 of the vehicle body 3, and a vehicle body display unit 142 that indicates the vehicle body 3 whose display position is changed according to the orientation F1 of the vehicle body 3. According to this, even if the operator cannot accurately grasp the orientation F1 of the vehicle body 3 in the work area, by looking at the orientation pointer unit 141 and the vehicle body display unit 142 displayed on the display device 45, the orientation F1 of the vehicle body 3 can be easily grasped.

[0086] The display device 45 includes an orientation scale unit 145 that uses the orientation F2 of the travel reference line L1 as a reference point and the value indicating the orientation increases or decreases according to the distance from the reference point. The line orientation display unit 130 includes a mark unit 130b that indicates that the orientation of the travel reference line is the reference point. According to this, by the operator looking at the scale unit 145, it is possible to easily grasp in which direction the orientation F2 of the travel reference line L1 is with respect to the vehicle body 3.

[0087] The vehicle body orientation display unit 140 includes an orientation pointer unit 141 that indicates the orientation F1 of the vehicle body 3, and the orientation pointer unit 141 indicates the orientation F1 of the vehicle body 3 on the orientation scale unit 145. According to this, by looking at the orientation pointer unit 141 indicated on the orientation scale unit 145, it is possible to easily grasp how much the orientation F1 of the vehicle body 3 is deviated from the travel reference line L1. The display form of the vehicle body orientation display unit 140 is different when the orientation difference ΔF between the orientation F2 of the travel reference line L1 and the orientation F1 of the vehicle body 3 is within a predetermined range and when the orientation difference ΔF is outside the predetermined range. According to this, the operator can easily grasp whether the orientation difference ΔF is within the predetermined range.

[0088] When the orientation difference ΔF between the orientation F2 of the travel reference line L1 and the orientation F1 of the vehicle body 3 is within a predetermined range The control device 60B is provided to permit automatic steering. According to this, it is possible to easily perform switching from manual steering to automatic steering and the like. The embodiments disclosed herein should be considered 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 modifications within the meaning and scope equivalent to the claims be included.

Explanation of Reference Numerals

[0089] 1 Work vehicle 3 Vehicle body 11 Steering device 30 Steering wheel 40 Positioning device 45 Display device 52 Steering changeover switch 60B Control device (second control device) L1 Travel reference line

Claims

1. A steering device having a steering wheel, A vehicle body capable of traveling by either manual steering by the steering wheel or automatic steering of the steering wheel based on a travel reference line, A positioning device capable of detecting the orientation of the vehicle body, A display device having a line orientation display unit indicating the orientation of the travel reference line and a vehicle body orientation display unit indicating the orientation of the vehicle body, A control device that permits the automatic steering when the orientation difference, which is the difference between the orientation of the vehicle body detected by the positioning device and the orientation of the travel reference line, is within a determination range, and performs automatic steering by the steering device when the permission is granted, An inclination detection device that detects the inclination of the vehicle body in the width direction, Comprising, The display device displays the orientation for which the automatic steering is permitted as a deviation of the vehicle body orientation display unit with respect to the travel reference line, The control device determines whether to permit the automatic steering according to the inclination of the vehicle body in the width direction detected by the inclination detection device, When it is determined that the automatic steering is permitted according to the inclination of the vehicle body in the width direction, the display device displays that the automatic steering is possible, The determination range is the case where the inclination of the vehicle body in the width direction is zero, and with a reference line where the orientation of the vehicle body and the orientation of the travel reference line coincide as the center, the absolute values of the lower limit value on one side and the upper limit value on the other side are the same value, and it is the range from the lower limit value to the upper limit value with the reference line as the center, The control device determines whether to permit the automatic steering based on the determination range, The display device displays that the automatic steering is possible when the orientation difference is within the determination range, and displays that the automatic steering is impossible when the orientation difference is outside the determination range, a work vehicle.

2. The work vehicle according to claim 1, wherein the line orientation display unit includes a line display unit indicating the travel reference line and a mark unit indicating that it is the orientation of the travel reference line.

3. The work vehicle according to claim 1 or 2, wherein the vehicle body orientation display unit includes an orientation pointer unit indicating the orientation of the vehicle body and a vehicle body display unit indicating the vehicle body whose display position is changed according to the orientation of the vehicle body.

4. The work vehicle according to any one of claims 1 to 3, wherein the display form of the vehicle body orientation display unit is different when the orientation difference between the orientation of the travel reference line and the orientation of the vehicle body is within a predetermined range and when the orientation difference is outside the predetermined range.

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