Patent Description:
Document <CIT> discloses a conventional agricultural working machine. The agricultural working machine of document <CIT> is provided with a traveling body capable of switching between manual traveling by manual steering and automatic traveling by automatic steering along a set traveling line parallel to a reference traveling line, and a changeover switch capable of switching between the manual traveling and the automatic traveling. In addition, the agricultural working machine sets a starting point of the reference traveling line after pressing a right indicator button while traveling along the ridges, and sets an end point of the reference traveling line by pressing a left indicator button while traveling. That is, the reference traveling line is set before the automatic steering.

A steering system is known from the Document <CIT>. A work vehicle and an automatic steering system are known from the Document <CIT>.

In the agricultural working machine of <CIT>, the automatic traveling can be easily performed by switching from the manual traveling to the automatic traveling with a changeover switch.

In the automatic traveling, it is desirable that the agricultural working machine is traveling in a straight line just before the start of automatic traveling, in order to control the agricultural working machine to travel along a reference traveling line. When starting the automatic traveling under a state where the agricultural working machine does not travel in a straight line, the initial behavior of the agricultural working machine may be unstable.

In addition, in the patent, it is difficult to drive the agricultural working machine along a set traveling line set on a slope. That is, it is difficult to make the agricultural working machine travel along the set traveling line under a state where the agricultural working machine is inclined.

In addition, since the agricultural working machine travels along the reference traveling line in the automatic traveling, a traveling orientation of the agricultural working machine is often the same as an orientation of the reference traveling line just before the automatic operation, and when the orientation of the agricultural working machine and the direction of the reference traveling line are greatly out of line, the initial behavior of the agricultural working machine may be unstable. In particular, under a state where the agricultural working machine is traveling on a slope, the automatic steering is required to be adapted to the slope because the orientation of the agricultural working machine is likely to change easily.

In view of the above problems, the present invention is intended to provide a working vehicle configured to be driven stably when switching from the manual steering to the automatic steering.

In addition, the present invention is intended to provide a working vehicle configured to be easily driven along a scheduled traveling line.

In addition, the present invention is intended to provide a working vehicle configured to perform the automatic steering stably.

Technical means of the present invention for solving this technical problem is characterized by the following points.

A working vehicle according to an aspect of the present invention, includes: a steering device having a steering handle; a vehicle body to travel with either manual steering by the steering handle or automatic steering of the steering handle based on a reference traveling line; a positioning device configured to detect an orientation of the vehicle body; and a display device including: a line orientation display portion to indicate an orientation of the reference line; a vehicle orientation display portion to indicate the orientation of the vehicle body and an orientation scale portion having a reference point that coincides with the orientation of the reference traveling line and being configured to increase and decrease a value indicating the orientation of the reference traveling line based on a distance from the reference point; and a controller device configured to permit the automatic steering by the steering device when an orientational difference which is a difference between the orientation of the vehicle body detected by the positioning device and the orientation of the reference traveling line is within a judgment range and to perform the automatic steering by the steering device when permitting the automatic steering, the working vehicle being characterized by comprising: an inclination detector device configured to detect an inclination of the vehicle body in a width direction, wherein the orientation scale portion is configured to show the judgment range, the controller device is configured to change the judgment range in accordance with the inclination of the vehicle body in the width direction detected by the inclination detector device, and the orientation scale portion is configured to, when the judgment range is changed in accordance with the inclination of the vehicle body in the width direction, show the changed judgment range.

In some embodiments, the controller device is configured to set a standard range centered on a reference line and having a lower limit and an upper limit which are on opposite sides of the reference line and which have the same absolute value, the reference line being a line on which the orientation of the vehicle body and the orientation of the reference traveling line coincide with each other, set the judgment range to the standard range when the inclination of the vehicle body in the width direction is zero, determine whether or not to permit the automatic steering based on the standard range, and cause the display device to display the judgment range set to the standard range. The controller device is further configured to, when the vehicle body is in a first inclined state in which one of opposite sides of the vehicle body in the width direction is higher than the other, change the judgment range to obtain a changed judgment range by increasing the absolute value of the lower limit of the judgment range such that the lower limit has an absolute value greater than that of the lower limit of the standard range, determine whether or not to permit the automatic steering based on the changed judgment range, and cause the display device to display the changed judgment range. The controller device is further configured to, when the vehicle body is in a second inclined state in which the one of the opposite sides of the vehicle body in the width direction is lower than the other, change the judgment range to obtain a changed judgment range by increasing the absolute value of the upper limit of the judgment range such that the upper limit has an absolute value greater than that of the upper limit of the standard range, determine whether or not to permit the automatic steering based on the changed judgment range, and cause the display device to display the changed judgment range.

In some embodiments, the controller device is configured to, when the vehicle body is in the first inclined state, change the judgment range to obtain a changed judgment range by reducing the absolute value of the upper limit of the judgment range such that the upper limit has an absolute value less than that of the upper limit of the standard range, determine whether or not to permit the automatic steering based on the changed judgment range, and cause the display device to display the changed judgment range. The controller device is further configured to, when the vehicle body is in the second inclined state, change the judgment range to obtain a changed judgment range by reducing the absolute value of the lower limit of the judgment range such that the lower limit has an absolute value less than that of the lower limit of the standard range, determine whether or not to permit the automatic steering based on the changed judgment range, and cause the display device to display the changed judgment range.

The line orientation display portion includes: a line display portion to indicate the reference traveling line; and a mark portion to indicate an orientation of the reference traveling line at the reference point.

The vehicle orientation display portion includes: an orientation pointer portion to point the orientation of the vehicle body; and a vehicle display portion to display the vehicle body whose display position is changed based on the orientation of the vehicle body.

The vehicle orientation display portion includes an orientation pointer portion to point the orientation of the vehicle body, and the orientation pointer points the orientation of the vehicle body on the orientation scale portion.

The vehicle orientation display portion has a display format provided when the orientational difference between the orientation of the reference traveling line and the orientation of the vehicle body is within the judgement range and another display format provided when the orientational difference is out of the judgement range.

According to the present invention, a traveling vehicle can be driven stably when switching from manual steering to automatic steering.

In addition, according to the present invention, it is possible to perform automatic steering stably even when a vehicle body is tilted because of some reason.

In addition, according to the present invention, automatic steering can be performed stably.

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

<FIG> is a side view of the working vehicle <NUM>, and <FIG> is a plan view of the working vehicle <NUM>. In this embodiment, the working vehicle <NUM> is a tractor. However, the working vehicle <NUM> is not limited to a tractor and may be an agricultural machine (agricultural vehicle) such as a combine or a transplanter, or construction equipment (construction vehicle) such as a loader working machine.

In the following description, the front side of an operator seated on an operator seat <NUM> of the tractor (working vehicle) <NUM> (a direction of an arrowed line A1 in <FIG>) will be referred to as the front, the rear side of the operator (a direction of an arrowed line A2 in <FIG>) will be referred to as the rear, the left side of the operator will be referred to as the left, and the right side of the operator will be referred to as the right. The horizontal direction, which is a direction orthogonal to the front-to-back direction of the working vehicle <NUM>, is referred to as a vehicle width direction.

As shown in <FIG>, the tractor <NUM> is provided with a vehicle body <NUM>, a prime mover <NUM>, and a speed-shifter device <NUM>. The vehicle body <NUM> has a traveling device <NUM>, which allows the vehicle body <NUM> to travel. The traveling device <NUM> is a device having a front wheel 7F and a rear wheel 7R. The front wheels 7F may be tire-type or crawler-type. The rear wheels 7R also may be tire-type or crawler-type.

The prime mover <NUM> is constituted of a diesel engine, an electric motor or the like, the prime mover <NUM> is the diesel engine in this embodiment. The speed-shifter device <NUM> is capable of switching the propulsion of the traveling device <NUM> by shifting gears and also of switching the traveling device <NUM> between the forward traveling and the backward traveling. The vehicle body <NUM> is provided with the operator seat <NUM>.

The rear portion of the vehicle body <NUM> is provided with a coupler portion <NUM> consisting of a three-point linkage mechanism or the like. A working device can be attached to and detached from the coupler portion <NUM>. By connecting the working device to the coupler portion <NUM>, the working device can be towed by the vehicle body <NUM>. The working device includes a cultivator device for tilling, a fertilizer sprayer device for spraying fertilizer, a pesticide sprayer device for spraying pesticides, a harvester device for harvesting, a mower device for harvesting grasses and the like, a tedder device for diffusing grasses and the like, a raking device for collecting grasses and the like, and a baler device for molding grasses and the like.

As shown in <FIG>, the speed-shifter device <NUM> is provided with a main shaft (propulsion shaft) 5a, a main speed-shifter portion 5b, a sub speed-shifter portion 5c, a shuttle portion 5d, a PTO power transmission 5e, and a front speed-shifter portion 5f. The propulsion shaft 5a is rotatably supported in a housing case (transmission case) of the speed-shifter device <NUM>, and power from the crankshaft of the prime mover <NUM> is transmitted to the propulsion shaft 5a. The main speed-shifter portion 5b has a plurality of gears and a shifter for changing the engagement of the gears. The main speed-shifter portion 5b changes the rotation input from the propulsion shaft 5a and outputs (shifts the speed) by changing the connection (engagement) of the plurality of gears with the shifter accordingly.

The sub speed-shifter portion 5c, like the main speed-shifter portion 5b, has a plurality of gears and a shifter for changing the engagement of the gears. By changing the connection (engagement) of the plurality of gears with the shifter as appropriate, the sub speed-shifter portion 5c changes the rotation input from the main speed-shifter portion 5b and outputs the changed rotation (speed shifting).

The shuttle portion 5d has a shuttle shaft <NUM> and a forward/backward switching portion <NUM>. The power output from the sub speed-shifter portion 5c is transmitted to the shuttle shaft <NUM> via gears and other devices. The forward/backward switching portion <NUM> includes, for example, a hydraulic clutch or the like, and switches the direction of rotation of the shuttle shaft <NUM>, that is, the forward movement and backward movement of the tractor <NUM>, by engaging and disengaging the hydraulic clutch. The shuttle shaft <NUM> is connected to a rear wheel differential device 20R. The rear wheel differential device 20R rotatably supports the rear axle 21R on which the rear wheel 7R is mounted.

The PTO power transmission 5e has a PTO propulsion shaft <NUM> and a PTO clutch <NUM>. The PTO propulsion shaft <NUM> is rotatably supported, and the power from the propulsion shaft 5a can be transferred from the propulsion shaft 5a. The PTO propulsion shaft <NUM> is connected to the PTO shaft <NUM> via the gears and the like. The PTO clutch <NUM> includes, for example, a hydraulic clutch and the like, and is switched between a state where the power of the propulsion shaft 5a is transferred to the PTO propulsion shaft <NUM> and a state where the power of the propulsion shaft 5a is not transferred to the PTO propulsion shaft <NUM>.

The front speed-shifter device 5f has a first clutch <NUM> and a second clutch <NUM>. The first clutch <NUM> and the second clutch are capable of transmitting power from the propulsion shaft 5a, for example, the power of the shuttle shaft <NUM> is transmitted via the gears and the transmission shaft. The power from the first clutch <NUM> and the second clutch <NUM> can be transmitted to the front axle 21F via the front transmission shaft <NUM>. In particular, the front transmission shaft <NUM> is connected to a front wheel differential device 20F, which rotatably supports the front axle 21F on which the front wheels 7F are mounted.

The first clutch <NUM> and the second clutch <NUM> include a hydraulic clutch or the like. A fluid line is connected to the first clutch <NUM>, and the fluid line is connected to a first actuator valve <NUM>, to which the hydraulic fluid discharged from the hydraulic pump is supplied. The first clutch <NUM> is switched between an engaged state and a disengaged state depending on the degree of opening of the first actuator valve <NUM>. A fluid line is connected to the second clutch <NUM>, and the fluid line is connected to a second actuator valve <NUM>. The second clutch <NUM> is switched between an engaged state and a disengaged state depending on the degree of opening of the second actuator valve <NUM>. The first and second actuation valves <NUM> and <NUM> are, for example, two-position switching valves with solenoid valves, which are switched to an engaged state or a disengaged state by magnetization or demagnetization of the solenoid valve solenoids.

When the first clutch <NUM> is disengaged and the second clutch <NUM> is engaged, the power of the shuttle shaft <NUM> is transmitted to the front wheels 7F through the second clutch <NUM>. This results in four-wheel driving (4WD) in which the front and rear wheels are driven by the power and the rotation speed of the front and rear wheels is substantially the same (4WD constant speed state). On the other hand, when the first clutch <NUM> is engaged and the second clutch <NUM> is disengaged, four-wheel driving is provided and the rotation speed of the front wheel becomes higher than that of the rear wheel (4WD constant speed state). When the first and second clutches <NUM> and <NUM> are disengaged, the power of the shuttle shaft <NUM> is not transmitted to the front wheels 7F, and thus the vehicle becomes two-wheel drive (2WD) with the rear wheels driven by power.

The tractor <NUM> is provided with a positioning device <NUM>. The positioning device <NUM> is capable of detecting its own position (positioning information including latitude and longitude) by a satellite positioning system (positioning satellite) such as D-GPS, GPS, GLONASS, HOKUTO, GALILEO, MICHIBIKI, and the like. That is, the positioning device <NUM> receives satellite signals transmitted by the positioning satellite (such as the position of the positioning satellite, transmission time, correction information, and the like) and detects its position (for example, latitude and longitude) based on the satellite signals. The positioning device <NUM> has a receiver device <NUM> and an inertial measurement device (IMU: Inertial Measurement Unit) <NUM>. The receiver device <NUM> has an antenna or the like and receives satellite signals transmitted from a positioning satellite, and is attached to the vehicle body <NUM> separately from the inertial measurement unit <NUM>. In this embodiment, the receiver device <NUM> is attached to a ROPS provided to the vehicle body <NUM>. The attachment location of the receiver device <NUM> is not limited to that of this embodiment.

The inertial measurement device <NUM> has an acceleration sensor to detect acceleration, a gyroscope to detect angular velocity, and so forth. The vehicle body <NUM>, for example, is installed below the operator seat <NUM>, and the roll angle, pitch angle, yaw angle, and the like of the vehicle body <NUM> can be detected by the inertial measurement device <NUM>.

As shown in <FIG>, the tractor <NUM> is provided with a steering device <NUM>. The steering device <NUM> is a device capable of performing manual steering to steer the body of the vehicle body <NUM> by the operator and automatic steering to steer the body of the vehicle body <NUM> automatically without the operator's operation.

The steering device <NUM> has a steering handle (steering wheel) <NUM> and a steering shaft (rotating shaft) <NUM> that rotatably supports the steering handle <NUM>. The steering device <NUM> also has an assist mechanism (power steering device) <NUM>. The assist mechanism <NUM> assists the rotation of the steering shaft <NUM> (steering handle <NUM>) by hydraulic or other means. The assist mechanism <NUM> includes a hydraulic pump <NUM>, a control valve <NUM> to which the hydraulic fluid discharged from the hydraulic pump <NUM> is supplied, and a steering cylinder <NUM> operated by the control valve <NUM>. The control valve <NUM> is, for example, a three-position switching valve that can be switched by movement of a spool or the like, and is switched in response to the steering direction (direction of rotation) of the steering shaft <NUM>. The steering cylinder <NUM> is connected to an arm (knuckle arm) <NUM> that changes the direction of the front wheels 7F.

Thus, when the operator grasps the steering wheel <NUM> and operates the steering wheel <NUM> in one direction or the other, the switching position and opening degree of the control valve <NUM> will be switched according to the direction of rotation of the steering wheel <NUM>, and the steering cylinder <NUM> will stretch and shorten to the left or right according to the switching position and opening degree of the control valve <NUM>. The direction of steering of the front wheels 7F can be changed by the steering wheel <NUM>. In other words, the vehicle body <NUM> can change the direction of travel to the left or right by manual steering of the steering handle <NUM>.

Next, automatic steering will be explained.

As shown in <FIG>, when automatic steering is performed, first, a reference traveling line L1 is set before automatic steering is performed. After the reference traveling line L1 is set, the automatic steering can be performed by setting the scheduled traveling line L2, which is parallel to the reference traveling line L1. The automatic steering automatically steers the tractor <NUM> (vehicle body <NUM>) in the direction of traveling so that the vehicle position measured by the positioning device <NUM> and the scheduled traveling line L2 coincide.

In particular, when the tractor <NUM> (vehicle body <NUM>) is moved to a predetermined position in the field prior to the automatic steering (S1), and at the predetermined position, the operator operates the steering changeover switch <NUM> provided on the tractor <NUM> (step S2), the vehicle position measured by the positioning device <NUM> is set at the start point P10 of the reference traveling line L1 (step S3). When the tractor <NUM> (vehicle body <NUM>) is moved from the start point P10 of the reference traveling line L1 (step S4) and the operator operates the steering changeover switch <NUM> at the predetermined position (step S5), the vehicle position measured by the positioning device <NUM> is set at the end point P11 of the reference traveling line L1 (step S6). Thus, a straight line connecting the start point P10 and the end point P11 is set as the reference traveling line L1.

After setting the reference traveling line L1 (after step S6), for example, when the tractor <NUM> (vehicle body <NUM>) is moved to a different location than where the reference traveling line L1 was set (step S7) and the operator operates the steering changeover switch <NUM> (step S8), the scheduled traveling line L2, which is a straight line parallel to the reference traveling line L1, is set (step S9). After the scheduled traveling line L2 is set, the automatic steering is started and the direction of traveling of the tractor <NUM> (vehicle body <NUM>) is changed so that it follows the scheduled traveling line L2. For example, when the current vehicle position is on the left side of the scheduled traveling line L2, the front wheel 7F is steered to the right, and when the current vehicle position is on the right side of the scheduled traveling line L2, the front wheel 7F is steered to the left. During the automatic steering, the travel speed (vehicle speed) of the tractor <NUM> (vehicle body <NUM>) can be changed by the operator manually changing the amount of operation of the gas pedal members (accelerator pedal and gas pedal lever) provided in the tractor <NUM>, or by changing the gear shift of the speed shifter (transmission).

After the start of the automatic steering, the automatic steering can be terminated when the operator operates the steering changeover switch <NUM> at any point. That is, the end point of the scheduled traveling line L2 can be set by the end of the automatic steering by operating the steering changeover switch <NUM>. In other words, the length of the end point of the scheduled traveling line L2 can be set longer or shorter than the reference traveling line L1. In other words, the scheduled traveling line L2 is not associated with the length of the reference traveling line L1, and the scheduled traveling line L2 allows the vehicle to travel a longer distance than the length of the reference traveling line L1 under the automatic steering.

As shown in <FIG>, the steering device <NUM> has an automatic steering mechanism <NUM>. The automatic steering mechanism <NUM> is a mechanism for the automatic steering of the vehicle body <NUM> and automatically steers the vehicle body <NUM> based on the position of the vehicle body <NUM> (vehicle position) detected by the positioning device <NUM>. The automatic steering mechanism <NUM> is provided with a steering motor <NUM> and a gear mechanism <NUM>. The steering motor <NUM> is a motor whose rotational direction, rotational speed, rotational angle, and the like can be controlled based on the vehicle position. The gear mechanism <NUM> includes a gear provided on the steering shaft <NUM> and traveling in conjunction with the steering shaft <NUM>, and a gear provided on the rotation shaft of the steering motor <NUM> and traveling in conjunction with the rotation shaft of the steering motor <NUM>. When the rotation shaft of the steering motor <NUM> rotates, the steering shaft <NUM> automatically rotates (revolves) via the gear mechanism <NUM> to change the steering direction of the front wheels 7F so that the vehicle position coincides with the scheduled traveling line L2.

As shown in <FIG>, the tractor <NUM> is provided with a display device <NUM>. The display device <NUM> is capable of displaying various information about the tractor <NUM>, at least the operation information of the tractor <NUM>. The display device <NUM> is located in front of the operator seat <NUM>.

As shown in <FIG>, the tractor <NUM> is provided with a setter switch <NUM>. The setter switch <NUM> is a switch that switches to a setting mode that is set at least prior to the start of the automatic steering. The setting mode is a mode for making various settings related to the automatic steering before starting the automatic steering, for example, setting a start and end point of the reference traveling line L1.

The setter switch <NUM> is switchable to ON or OFF, and outputs a signal that the setting mode is enabled when it is ON, and outputs a signal that the setting mode is disabled when it is OFF. The setter switch <NUM> also outputs a signal to the display device <NUM> that the setting mode is enabled when it is ON, and outputs a signal to the display device <NUM> that the setting mode is disabled when it is OFF.

The tractor <NUM> is provided with the steering changeover switch <NUM>. The steering changeover switch <NUM> is a switch that switches the start or end of the automatic steering. In particular, the steering changeover switch <NUM> is switchable from the neutral position to up, down, forward, or backward, and issues a start of the automatic steering when switched downward from the neutral position with the setting mode enabled, and issues an end of the automatic steering when switched upward from the neutral position with the setting mode enabled. The steering changeover switch <NUM> also issues to set the current vehicle position to the start point P10 of the reference traveling line L1 when switched from the neutral position to the rear with the setting mode enabled, and the steering changeover switch <NUM> issues to set the current vehicle position to the end point P11 of the reference traveling line L1 when switched from the neutral position to the front with the setting mode enabled. That is, the steering changeover switch <NUM> serves as both of a reference traveling line setter witch for setting the start position (start point P10) of the reference traveling line L1 and a reference traveling line setter witch for setting the end position (end point P11) of the reference traveling line L1. The steering changeover switch <NUM> may be configured separately from the reference traveling line setter switch and the steering changeover switch <NUM>, which switches the start or end of the automatic steering.

The tractor <NUM> is provided with a corrector switch <NUM>. The corrector switch <NUM> is a switch that corrects the vehicle position (latitude and longitude) measured by the positioning device <NUM>. That is, the corrector switch <NUM> corrects the vehicle position (called the calculated vehicle position) calculated with the satellite signal (position of the positioning satellite, transmission time, correction information, and the like) and the measurement information (acceleration, angular velocity) measured by the inertial measurement device <NUM>.

The corrector switch <NUM> includes a push switch or a slide switch, which can be pressed or slidable. Hereinafter, a case in which the corrector switch <NUM> is a push switch and a case in which the corrector switch <NUM> is a slide switch respectively will be described.

When the corrector switch <NUM> 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 following formula: correction amount = number of operations × correction amount per operation count. For example, as shown in <FIG>, each operation of the push switch increases the amount of correction by a few centimeters or tens of centimeters. The number of operations of the push switch is input to the first controller device 60A, and the first controller device 60A sets (calculates) the correction amount based on the number of operations.

When the corrector switch <NUM> is a slide switch, the amount of correction is set based on the amount of operation (displacement amount) of the slide switch. For example, the correction amount is determined by the correction amount = the amount of displacement from a predetermined position. For example, as shown in <FIG>, for every <NUM> increase in the displacement of the slide switch, the amount of correction is increased by a few centimeters or tens of centimeters. The amount of operation of the slide switch (displacement amount) is input to the first controller device 60A, and the first controller device 60A sets (calculates) the correction amount based on the displacement amount. The method of increasing the correction amount and the rate of increase is not limited to the values described above.

In detail, as shown in <FIG> and <FIG>, the corrector switch <NUM> has a first corrector portion 53A and a second corrector portion 53B. The first corrector portion 53A is the part that commands correction of the vehicle position corresponding to one side, that is, the left side, of the vehicle body <NUM> in the width direction. The second corrector portion 53B is the part that commands correction of the vehicle position corresponding to the other side in the width direction of the vehicle body <NUM>, that is, the right side.

As shown in <FIG>, when the corrector switch <NUM> is a push switch, the first corrector portion 53A and the second corrector portion 53B are on or off switches that automatically return at each operation. The switch including the first corrector portion 53A and the switch including the second corrector portion 53B are integrated with the switch including the first corrector portion 53A. The switch including the first corrector portion 53A and the switch including the second corrector portion 53B may be disposed apart from each other. As shown in <FIG>, each time the first corrector portion 53A is pressed, the amount of correction corresponding to the left side of the vehicle body <NUM> (the left correction amount) is increased. Also, each time the second corrector portion 53B is pressed, the amount of correction corresponding to the right side of the vehicle body <NUM> (the right correction amount) increases.

As shown in <FIG>, when the corrector switch <NUM> is a slide switch, the first and second corrector portions 53A and 53B include a pinching portion <NUM> that moves left or right along the longitudinal direction of the long hole. When the corrector switch <NUM> is a slide switch, the first and second corrector portions 53A and 53B are disposed apart from each other in the width direction. As shown in <FIG>, when the pinching portion <NUM> is gradually displaced to the left side from the predetermined reference position, the left correction amount increases in accordance with the displacement amount. When the pinching portion <NUM> is gradually displaced to the right side from the predetermined reference position, the right correction amount increases in accordance with the displacement amount. As shown in <FIG>, in the case of a slide switch, the first corrector portion 53A and the second corrector portion 53B are formed in an integrated manner, and the reference position of the pinching portion <NUM> is set at the center, and when the pinching portion <NUM> is displaced to the left from the reference position, the left correction amount is set, and when the pinching portion <NUM> is displaced to the right from the middle position, the right correction amount is set.

Next, the relation between the correction amount (left and right correction amounts) by the corrector switch <NUM>, the scheduled traveling line L2, and the behavior of the tractor <NUM> (vehicle body <NUM>) (traveling trajectory) will be explained.

<FIG> shows the situation when the calculated vehicle position W1 shifts to the right during the automatic steering and straight ahead. As shown in <FIG>, when the automatic steering is started and the actual position of the tractor <NUM> (vehicle body <NUM>) (actual position W2) is the same as the calculated vehicle position W1, and the actual position W2 is the same as the scheduled traveling line L2, the tractor <NUM> will travel along the scheduled traveling line L2. That is, in the sector P1 where there are no errors in the positioning of the positioning device <NUM> and the vehicle position (calculated vehicle position W1) detected by the positioning device <NUM> is the same as the actual position W2, the tractor <NUM> travels along the scheduled traveling line L2. When there are no errors in positioning by the positioning system <NUM> and no corrections are made, the calculated vehicle position W1 is the same as the corrected vehicle position (corrected vehicle position) W3, corrected by the correction amount. The corrected vehicle position W3 is calculated by the following formula: corrected vehicle position W3 = calculated vehicle position W1 - correction amount.

Here, in the vicinity of the position P20, although the actual position W2 is not out of alignment with the scheduled traveling line L2, various effects cause errors in positioning by the positioning device <NUM>, and the vehicle position W1 detected by the positioning device <NUM> is shifted to the right side with respect to the scheduled traveling line L2 (actual position W2), resulting in the offset amount (gap or deviation) W4. Then, the tractor <NUM> judges that there is a gap between the calculated vehicle position W1 and the scheduled traveling line L2, and steers the tractor <NUM> to the left so that the offset amount W4 between the calculated vehicle position W1 and the scheduled traveling line L2 is eliminated. Then, the actual position W2 of the tractor <NUM> shifts to the scheduled traveling line L2 by steering left. Then, it is supposed that the operator notices that the tractor <NUM> has shifted from the scheduled traveling line L2 and steers the second corrector portion 53B at position P21 to increase the right correction amount from zero. The right-hand correction is added to the calculated vehicle position W1, and the corrected vehicle position W3 can be made to be substantially the same as the actual position W2. In other words, the vehicle position of the positioning system <NUM> can be corrected by the second corrector portion 53B in the direction to eliminate the offset amount W4 that occurred in the vicinity of the position P20. As shown in position P21 in <FIG>, when the actual position W2 of the tractor <NUM> is far to the left of the scheduled traveling line L2 after the vehicle position correction, the tractor <NUM> can be steered to the right to bring the actual position W2 of the tractor <NUM> in line with the scheduled traveling line L2.

<FIG> shows a case in which the calculated vehicle position W1 shifts to the left while the vehicle is moving straight ahead during the automatic steering. As shown in <FIG>, when the actual position W2 and the calculated vehicle position W1 coincide with the actual position W2 and the scheduled traveling line L2 at the start of the automatic steering, as in <FIG>, the tractor <NUM> travels along the scheduled traveling line L2, as in <FIG>. That is, as in <FIG>, in the sector P2 where there is no error in the positioning of the positioning device <NUM>, tractor <NUM> travels along the scheduled traveling line L2. Also, as in <FIG>, the calculated vehicle position W1 and the corrected body position W3 are the same value.

When, at position P22, due to various effects, there is an error in the positioning of the positioning device <NUM>, and the vehicle position W1 detected by the positioning device <NUM> is shifted to the left side relative to the actual position W2, and the offset amount (gap or deviation) W5 is maintained, then the tractor <NUM> resolves the offset amount W5 between the calculated vehicle position W1 and the scheduled traveling line L2. The tractor <NUM> is steered to the right so as to do so. Then, it is supposed that the operator notices that tractor <NUM> is out of alignment with the scheduled traveling line L2 and the operator steers the first corrector portion 53A at position P23 to increase the left correction amount from zero. Then, the left correction amount is added to the calculated vehicle position W1, and the corrected vehicle position (corrected body position) W3 can be made substantially the same as the actual position W2. In other words, by setting the left correction amount using the first corrector portion 53A, the vehicle position of the positioning system <NUM> can be corrected in a direction that eliminates the offset amount W5 that occurred in the vicinity of position P22. As shown in position P23 in <FIG>, when the actual position W2 of the tractor <NUM> is far to the right of the scheduled traveling line L2 after the vehicle position correction, the tractor <NUM> can be steered to the left to bring the actual position W2 of the tractor <NUM> in line with the scheduled traveling line L2.

Next, the setter switch <NUM> and the corrector switch <NUM> will be described.

As shown in <FIG>, the outer perimeter of the steering shaft <NUM> is covered by the steering post <NUM>. The outer perimeter of the steering post <NUM> is covered by a cover <NUM>. The cover <NUM> is provided in front of the operator seat <NUM>. The cover <NUM> includes a panel cover <NUM> and a column cover <NUM>.

The panel cover <NUM> supports the display device <NUM>. The upper panel portion 178a of the panel cover <NUM> is provided with a support portion 178e that supports the display device <NUM>. The support portion 178e supports the display device <NUM> in front of the steering shaft <NUM> and below the steering handle <NUM>. The upper plate portion 178a has an attachment surface 178f to which the setter switch <NUM> and the corrector switch <NUM> are attached. The attachment surface 178f is located behind the support portion 178e and below the steering handle <NUM>. The support portion 178e and the attachment surface 178f are continuous, with the support portion 178e located in front of the upper plate portion 178a and the attachment surface 178f located at the rear portion of the upper plate portion 178a. The setter switch <NUM> and corrector switch <NUM> are mounted on the attachment surface 178f. The setter switch <NUM> and the corrector switch <NUM> are thereby arranged around the steering shaft <NUM>.

A shuttle lever <NUM> protrudes from the left plate portion 178b of the panel cover <NUM>. The shuttle lever <NUM> is a member that switches the direction of traveling of the vehicle body <NUM>. In more detail, by operating (pivoting) the shuttle lever <NUM> forward, the forward/backward switching portion <NUM> is in a state of outputting the forward traveling power to the traveling device <NUM>, and the traveling direction of the vehicle body <NUM> is switched to a forward traveling direction. By operating (pivoting) the shuttle lever <NUM> backward, the forward/backward switching portion <NUM> outputs backward traveling power to the traveling device <NUM> and the traveling direction of the vehicle body <NUM> is switched to the backward traveling direction. When the shuttle lever <NUM> is in the neutral position, no power is output to the traveling device <NUM>.

The column cover <NUM> is disposed below the steering wheel <NUM> and covers the outer perimeter of the upper portion of the steering shaft <NUM>. The column cover <NUM> is formed in the shape of a substantially square cylinder and protrudes upward from the attachment surface 178f of the panel cover <NUM>. In other words, the attachment surface 178f is provided around the perimeter of the column cover <NUM>. Thus, the setter switch <NUM> and corrector switch <NUM> mounted on the attachment surface 178f are located around the perimeter of the column cover <NUM>.

Next, the arrangement of the setter switch <NUM>, the steering changeover switch <NUM>, and the corrector switch <NUM> will be described in detail. As shown in <FIG>, the setter switch <NUM>, the steering changeover switch <NUM>, and the corrector switch <NUM> are arranged around the steering shaft <NUM>.

The setter switch <NUM> is located on one side (left side) of the steering shaft <NUM>. The steering changeover switch <NUM> is located on one side (left side) of the steering shaft <NUM>. In the case of this embodiment, the steering changeover switch <NUM> includes a pivotable lever. The steering changeover switch <NUM> is pivotable with a base point on the steering shaft <NUM> side. The base end of the steering changeover switch <NUM> is provided inside the column cover <NUM>. The steering changeover switch <NUM> protrudes on one side (left side) of the column cover <NUM>.

The corrector switch <NUM> is located on the other side (right side) of the steering shaft <NUM>. More specifically, the corrector switch <NUM> is disposed on the right side and rearward (diagonally right rearward) of the steering shaft <NUM>. The corrector switch <NUM> is disposed to the right and rear (diagonally right rear) of the column cover <NUM> in relation to the column cover <NUM>. The corrector switch <NUM> is disposed at the right rear portion of the attachment surface 178f in relation to the attachment surface 178f of the panel cover <NUM>. The fact that the corrector switch <NUM> is disposed at the rear portion of the inclined attachment surface 178f allows for a longer distance between the corrector switch <NUM> and the steering wheel <NUM>. This can more reliably prevent unintentional operation of the corrector switch <NUM> and steering wheel <NUM>.

As mentioned above, the setter switch <NUM>, the steering changeover switch <NUM>, the corrector switch <NUM> are arranged around the steering shaft <NUM>. In other words, the setter switch <NUM>, the steering changeover switch <NUM>, and the corrector switch <NUM> are present in a centralized location around the steering shaft <NUM>. Thus, the operator can clearly understand the location of each switch at a glance. In addition, the operator can operate each switch without changing his or her posture while seated on the operator seat <NUM>. As a result, the operability of the switches is improved and erroneous operation can be prevented. In addition, the harnesses (wiring) distributed from each switch can be shortened.

In addition, the above-mentioned switch arrangement may be arranged with the left and right sides interchangeable. That is, one side may be on the left and the other side on the right, or one side may be on the right and the other side on the left. In particular, for example, the setter switch <NUM> and the steering changeover switch <NUM> may be located on the right side of the steering shaft <NUM>, and the corrector switch <NUM> may be located on the left side of the steering shaft <NUM>.

As shown in <FIG>, the tractor <NUM> is provided with a plurality of controller devices <NUM>. The plurality of controller devices <NUM> are devices that control the traveling system, control the working system, calculate the vehicle position, and the like in the tractor <NUM>. The plurality of controller devices <NUM> are a first controller device 60A, a second controller device 60B, and a third controller device 60C.

The first controller device 60A receives the satellite signal received by the receiver <NUM> (received information) and the measurement information (acceleration, angular velocity, and the like) measured by the inertial measurement device <NUM>, and determines the vehicle body position based on the received information and the measurement information. For example, when the correction amount by the corrector switch <NUM> is zero, that is, the correction of the vehicle position by the corrector switch <NUM> is not commanded, the first controller device 60A does not correct the calculated vehicle position W1 calculated based on the received information and the measurement information, and determines the calculated vehicle position W1 as the vehicle position to be used for the automatic steering. On the other hand, when corrector switch <NUM> is commanded to correct the vehicle body position, the first controller device 60A sets the correction amount of the vehicle body position based on either the number of operations of the corrector switch <NUM> or the amount of operation of the corrector switch <NUM> (displacement amount), and then determines, as the vehicle position to be used for the automatic steering, the corrected vehicle position W3 obtained by correcting the calculated vehicle body position W1 with the correction amount.

The first controller device 60A sets a control signal based on the vehicle position (calculated vehicle position W1, corrected body position W3) and the scheduled traveling line L2, and outputs the control signal to the second controller device 60B. The second controller device 60B has an automatic steering controller portion <NUM>. The automatic steering controller portion <NUM> includes an electrical and electronic circuit in the second controller device 60B, a computer program stored in a CPU, and the like. The automatic steering controller portion <NUM> controls the steering motor <NUM> of the automatic steering mechanism <NUM> so that the vehicle body <NUM> travels along the scheduled traveling line L2 based on a control signal output from the first controller device 60A.

As shown in <FIG>, when the deviation between the vehicle position and the scheduled traveling line L2 is less than a threshold value, the automatic steering controller portion <NUM> maintains the rotation angle of the rotation axis of the steering motor <NUM>. When the deviation between the vehicle body position and the scheduled traveling line L2 (position deviation) is greater than or equal to the threshold value and the tractor <NUM> is located on the left side with respect to the scheduled traveling line L2, the automatic steering controller portion <NUM> rotates the rotation axis of the steering motor <NUM> so that the steering direction of the tractor <NUM> is in the right direction. That is, the automatic steering controller portion <NUM> sets the steering angle in the right direction so that the position deviation is zero. When the deviation between the vehicle position and the scheduled traveling line L2 is greater than or equal to a threshold value and the tractor <NUM> is located on the right side with respect to the scheduled traveling line L2, the automatic steering controller portion <NUM> rotates the rotational axis of the steering motor <NUM> so that the steering direction of the tractor <NUM> is in a left direction. That is, the automatic steering controller portion <NUM> sets the steering angle in the left direction so that the position deviation is zero. In the above-described embodiment, the steering angle of the steering device <NUM> is changed based on the deviation between the vehicle body position and the scheduled traveling line L2. However, when the orientation of the scheduled traveling line L2 differs from the orientation of the direction of the tractor <NUM> (vehicle body <NUM>) in the direction of travel (traveling direction) (vehicle body orientation) F1, that is, the vehicle body orientation to the scheduled traveling line L2. When the angle θg of F1 is greater than or equal to a threshold value, the automatic steering controller portion <NUM> may set the steering angle so that the angle θg becomes zero (vehicle orientation F1 matches the orientation of the scheduled traveling line L2). The automatic steering controller portion <NUM> may also set a 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 orientation (orientational deviation). The setting of the steering angle in the automatic steering in the above-described embodiments is an example and is not limited thereto.

The third controller device 60C raises and lowers the coupler portion <NUM> in response to the operation of an operating member provided around the operator seat <NUM>. The first controller device 60A, the second controller device 60B and the third controller device 60C may be integrated. The control of the traveling system, the control of the working system, and the calculation of the vehicle position as described above are not limited.

As described above, the tractor <NUM> (vehicle body <NUM>) can be steered automatically by the controller device <NUM>.

Now, to perform the automatic steering after the setting of the reference traveling line L1, the conditions for the automatic steering must be adjusted. For example, as shown in <FIG>, when the tractor <NUM> is turned and the tractor <NUM> meanders more than a predetermined distance before the automatic steering (when the vehicle orientation of the tractor <NUM> differs significantly from the reference traveling line L1), even when the automatic steering is started, it is not possible to steer the tractor along the scheduled traveling line L2 parallel to the reference traveling line L1. When it is difficult to steer tractor <NUM> in manual handling, the second controller device 60B determines that the conditions for the automatic steering are not in place.

The second controller device 60B permits the automatic steering at least before the automatic steering, that is, based on a plurality of steering angles θn (n = <NUM>, <NUM>, <NUM>. n) of the steering device <NUM> when the tractor <NUM> (vehicle body <NUM>) has traveled a predetermined distance in manual steering.

As shown in <FIG>, the second controller device 60B is provided with a steering angle obtainer portion <NUM> and a steering judgment portion <NUM>, in addition to the automatic steering controller portion <NUM>. The steering angle obtainer portion <NUM> and the steering judgment portion <NUM> include electrical and electronic circuits in the second controller device 60B, a computer program stored in a CPU or the like.

The steering angle obtainer portion <NUM> acquires a plurality of steering angles θn of the steering device <NUM> at least during the manual steering. The steering angle obtainer portion <NUM> acquires the steering angle θn detected by the steering angle detector device <NUM> on the vehicle body <NUM> at a predetermined time interval. As shown in <FIG>, it is supposed, for example, that the automatic steering is terminated when the steering changeover switch <NUM> is operated at position P12. After position P12, the steering angle θ in the turning interval T1 is a large value and the steering angle obtainer portion <NUM> does not acquire the steering angle θ in the turning interval T1 because the steering angle θ is a large value and the steering angle obtainer portion <NUM> can determine that the tractor <NUM> is in a turning state. The steering angle obtainer portion <NUM> continuously acquires a plurality of steering angles θn after position P13 where at least the current steering angle θM1 is less than or equal to the steering angle of the turn (the turning judgment steering angle θM2). The steering angle obtainer portion <NUM> acquires a plurality of steering angles θn within a predetermined judging distance J1 from position P13, for example, or within a predetermined judging time from position P13 by the tractor <NUM>.

The steering judgment portion <NUM> determines whether to permit the start of the automatic steering based on the plurality of steering angles θn acquired by the steering angle obtainer portion <NUM>. The steering judgment portion <NUM> permits the start of the automatic steering when the variation of the plurality of steering angles θn acquired by the steering angle obtainer portion <NUM> is within a predetermined range, and does not permit the automatic steering when the variation of the plurality of steering angles θn is out of the predetermined range.

As shown in <FIG>, the steering judgment portion <NUM>, for example, finds the standard deviation and the average value of the plurality of steering angles θn, and permits the start of the automatic steering when all the steering angles θn are within 3σ. On the other hand, as shown in <FIG>, the steering judgment portion <NUM> does not permit the start of the automatic steering when some of the steering angles θn are in a region that exceeds 3σ. In other words, the steering judgment portion <NUM> permits the automatic steering when the steering of the steering handle <NUM> is stable and the vehicle body <NUM> is considered to be moving in a straight direction, and does not permit the automatic steering when the steering of the steering handle <NUM> is not stable and the vehicle body <NUM> is not considered to be moving in a straight direction. In the above-mentioned embodiment, it is assumed that the steering angle obtainer portion <NUM> does not acquire a plurality of steering angles θn during turn traveling, but instead, the steering angle obtainer portion <NUM> may acquire a plurality of steering angles θn during turn traveling, and the steering judgment portion <NUM> may remove the steering angle θn during turn traveling from the plurality of steering angles θn acquired by the steering angle obtainer portion <NUM>, and then may judge the automatic steering with use of the removed steering angle θn.

The automatic steering controller portion <NUM> controls the steering device <NUM> as described above when the start of the automatic steering is switched by the steering changeover switch <NUM> when the start of the automatic steering is judged to be permitted by the steering judgment portion <NUM>, and the automatic steering is performed as described above.

The display device <NUM> is capable of displaying that the start of the automatic steering has been determined to be permitted by the steering judgment portion <NUM>. As shown in <FIG>, when a predetermined action is performed on the display device <NUM>, the display device <NUM> displays the driving screen M1.

The driving screen M1 has an operation display portion <NUM> showing operation information. The operation display portion <NUM> includes a revolutions display portion <NUM> that displays the number of revolutions of the prime mover <NUM> (motor speed) as operation information. The revolutions display portion <NUM> includes a level display portion <NUM>. The level display portion <NUM> is a portion that displays the number of prime mover revolutions in stages. For example, the level display portion <NUM> includes a scale portion <NUM> and an indicator portion <NUM>. The scale portion <NUM> has, for example, a first line 65A and a plurality of second lines 65B allocated at predetermined intervals along the first line 65A. The scale portion <NUM> also has a third line 65C separated from the first line 65A at predetermined intervals. The first line 65A and the third line 65C are, for example, formed in a semicircular shape, with one end (for example, the left side) representing the minimum value and the other end (for example, the right side) representing the maximum value.

The indicator portion <NUM> is a bar that varies in length according to the magnitude of the prime mover speed. The indicator portion <NUM> is located between the first line 65A and the third line 65C, for example, and has the shortest length at one end (left side) of the first line 65A and the third line 65C when the value of the prime mover speed is the minimum value of zero and has the longest length extending from one end (left side) of the first line 65A and the third line 65C to the other end of the first line 65A and the third line 65C (right side) when the value of the prime mover speed is the maximum value. The revolutions display portion <NUM> includes a numeric display portion <NUM>. The numeric display portion <NUM> displays the number of prime mover revolutions in numbers. For example, the revolutions display portion <NUM> is located inside the semicircle of the first line 65A and the third line 65C.

Thus, according to the operation display portion <NUM>, the revolutions speed of the prime mover such as the engine speed can be displayed in steps on the level display portion <NUM> and displayed numerically by the revolutions display portion <NUM>.

The driving screen M1 has an icon display portion <NUM> displaying a plurality of icons <NUM>. The icon display portion <NUM> is the portion where various information is indicated by the icon portion <NUM>. That is, the setting relating to the traveling such as the automatic steering, for example, the setting state set in the setting mode is displayed on the icon portions <NUM>. The icon display portion <NUM> is located in a different position from the driving display portion <NUM>, for example, at the top of the driving screen M1.

The plurality of icon portions <NUM> include the first icon portion 66A, the second icon portion 66B, the third icon portion 66C, the fourth icon portion 66D, the fifth icon portion 66E, the sixth icon portion 66F, and the seventh icon portion <NUM>. The driving screen M1 need not have all of the plurality of icon portions <NUM> (66A, 66B, 66C, 66D, 66E, 66F, and <NUM>) and is not limited to the embodiments described above.

The first icon portion 66A is displayed when a warning is issued. The second icon portion 66B is displayed when the start point P10 of the reference traveling line L1 is set. The third icon portion 66C is displayed when the end point P11 of the reference traveling line L1 is set.

The fourth icon portion 66D is displayed when the automatic steering is permitted. For example, the fourth icon portion 66D is displayed when the setting mode is valid and the setting of the reference traveling line L1 is completed, and the steering judgment portion <NUM> of the second controller device 60B has given permission for the automatic steering. By looking at the fourth icon portion 66D, the operator can see that the automatic steering is permitted. The operator can then start the automatic steering by operating the steering changeover switch <NUM>.

The fifth icon portion 66E is displayed when the coupler portion <NUM> is in the lifted and lowered state. The sixth icon portion 66F is displayed when the 4WD is in a state of increasing the speed. The seventh icon portion <NUM> changes color and other colors depending on the receiving sensitivity of the receiving signal of the receiver device <NUM>.

In the above-described embodiment, the condition for permission of the automatic steering is that the variation of the plurality of steering angles θn is within a predetermined range, but it may be added to the condition that the orientation of the tractor <NUM> (vehicle body <NUM>) before the automatic steering is within a predetermined range with respect to the orientation of the reference traveling line L1. As shown in <FIG>, in a situation where the tractor <NUM> (vehicle body <NUM>) is traveling in a judgment distance J1 after the position P13, the second controller device 60B permits the automatic steering with respect to the steering when the variation of the plurality of steering angles θn is within a predetermined range (first permit), and the orientation of the tractor <NUM> (vehicle body <NUM>) calculated by the positioning device <NUM> and others is the automatic steering with respect to orientation is permitted (second permit) when the orientation F1 and the direction of the reference traveling line L1 (direction of extension) calculated by the positioning device <NUM> and the like are within a predetermined range. The second controller device 60B then starts the automatic steering when the first and second permissions are aligned and the operator switches the start of the automatic steering.

The working vehicle <NUM> includes the steering device <NUM> having the steering handle <NUM>, the vehicle body <NUM> capable of traveling either in the manual steering with the steering handle <NUM> or in the automatic steering of the steering handle <NUM> based on the reference traveling line L1, and the controller device 60B that permits the automatic steering based on a plurality of steering angles of the steering device <NUM> obtained when the vehicle body <NUM> travels in a predetermined distance in the manual steering. According to this configuration, in a situation where the working vehicle <NUM> is traveling in the manual steering, it is possible to determine whether or not it is possible to shift from the manual steering to the automatic steering based on a plurality of steering angles, that is, the state of the transition of the steering angles.

For example, as shown in <FIG>, when the working vehicle <NUM> is traveling on a right downward slope (a higher left side and lower right side slope as viewed from the working vehicle <NUM>), the vehicle may be allowed to travel straight with the steering of the steering device <NUM> fixed to the left. In other words, when the steering direction of the steering device <NUM> is steered to the left, the vehicle will turn to the left in response to the steering direction on a level ground, but will travel straight on a slope, and the steering angle θ will be relatively large continuously compared to that on a level ground. Thus, in the case of an inclined ground, even when the steering angle θ is larger than on a level ground and continues continuously, the working vehicle <NUM> can properly judge straight ahead not only on a level ground but also on an inclined ground because the automatic steering is judged by a plurality of steering angles θn as described above, even when the steering angle θ is larger than on a level ground. This allows the working vehicle <NUM> to travel stably when switching from the manual steering to the automatic steering.

The working vehicle <NUM> is provided with the steering changeover switch <NUM> to switch either the start or end of the automatic steering. And, the controller device 60B has the steering angle obtainer portion <NUM> that acquires a plurality of steering angles, the steering judgment portion <NUM> that determines whether or not to permit the start of the automatic steering based on the plurality of steering angles acquired by the steering angle obtainer portion <NUM>, and the automatic steering controller portion <NUM> that controls the steering device <NUM> to perform the automatic steering when the start of the automatic steering is switched by the steering changeover switch <NUM> in a state determined to be permitted by the steering judgment portion <NUM>. According to this configuration, a plurality of steering angles during the manual steering can be acquired by the steering angle obtainer portion <NUM>, and the automatic steering can be performed by the automatic steering controller portion <NUM> after properly determining whether the automatic steering can be performed based on the plurality of steering angles by the steering judgment portion <NUM>.

The working vehicle <NUM> is provided with the display device <NUM> that displays that the start of the automatic steering is determined to be permitted by the steering judgment portion <NUM>. According to this configuration, the operator can easily understand whether or not the start of the automatic steering is permitted by simply looking at the display device <NUM>.

The steering judgment portion <NUM> permits the start of the automatic steering when the variation of the multiple steering angles is within a predetermined range. According to this configuration, the switch from manual to the automatic steering, that is, the start of the automatic steering, can be properly performed when the steering angles are stable.

The working vehicle <NUM> is provided with the positioning device <NUM> configured to detect the position of the vehicle body <NUM>, and the reference traveling line setter switch configured to set the position of the vehicle body <NUM> detected by the positioning device <NUM> to the start and end positions of the reference traveling line L1. According to this configuration, the reference traveling line setter switch allows the setting of the reference traveling line L1 to be easily performed.

A second embodiment will be described below.

Now, the controller device <NUM> changes the control of the automatic steering based on the inclining of the vehicle body <NUM>. The tilt of the vehicle body <NUM> is detected by an inclination detector device installed in the tractor <NUM> (vehicle body <NUM>). In this second embodiment, the inclination detector device is, for example, the inertial measurement device <NUM> having an acceleration sensor to detect acceleration, a gyroscope to detect angular velocity, and the like, which can detect the tractor <NUM> (vehicle body <NUM>). In addition, the inclination detector device may be a device including a plurality of positioning devices <NUM> (for example, a GPS compass, and the like), or it may be any other device.

As shown in <FIG>, the automatic steering controller portion <NUM> has a parameter corrector portion 200a, a steering angle calculator portion 200b, and a steering controller portion 200c. The parameter corrector portion 200a, the steering angle calculator portion 200b, and the steering controller portion 200c include electrical and electronic components provided in the controller device <NUM>, a computer program incorporated in the controller device <NUM>, and the like.

The parameter corrector portion 200a changes a parameter to be applied in the automatic steering based on the inclination of the vehicle body <NUM> detected by the inclination detector device. For example, when the field on which the tractor <NUM> (vehicle body <NUM>) travels is flat, the direction of traveling of the tractor <NUM> is easy to change to follow the magnitude of the steering angle of the steering device <NUM>. On the other hand, when the work field in which the tractor <NUM> (vehicle body <NUM>) travels is on a slope, the relation between the magnitude of the steering angle and the change in the direction of traveling of the tractor <NUM> changes more than on flat ground, since the tractor <NUM> (vehicle body <NUM>) is affected by the slope. Thus, the parameter corrector portion 200a changes the parameter when the inclination of the vehicle body <NUM> detected by the inclination detector device is greater than or equal to a predetermined threshold.

For example, as shown in <FIG>, when the tractor <NUM> is steered to one side (left side) of the tractor <NUM> in a work field where one side (left side) of the tractor <NUM> is high and the other side (right side) of the tractor <NUM> is low, that is, when the tractor <NUM> is steered toward the upward direction (upward) UP1, the parameter corrector portion 200a changes the parameter so that the steering angle is greater than a steering angle on a level ground without inclination. For example, the parameter corrector portion 200a corrects the parameter to increase the steering angle when either the angle of inclination of the vehicle body <NUM> in the width direction (roll angle) or the angle of inclination of the vehicle body <NUM> in the direction of travel (pitch angle) is other than a predetermined value, for example, +<NUM> degrees (deg) or more.

On the other hand, when tractor <NUM> is steered to the other side (right side) of a downward slope, that is, when tractor <NUM> is steered in the downward direction (downward side) DN1, the parameter corrector portion 200a changes the parameter so that the steering angle is smaller than a steering angle on a level ground without inclination. For example, the parameter corrector portion 200a corrects the parameter in a direction that decreases the steering angle when either the roll angle of the vehicle body <NUM> or the pitch angle of the vehicle body <NUM> is other than a predetermined value, for example, -<NUM> degrees (deg) or less. The threshold for the inclination of the vehicle body <NUM> is an example and is not limited thereto.

The parameter correction and the automatic steering by the parameter corrector portion 200a will be described in detail below.

The parameter corrector portion 200a determines the control gain G1, which is a parameter that determines the steering angle, based on the correction factor SG1 and a reference value (constant) SD1. That is, the parameter corrector portion 200a obtains the control gain G1 by the control gain G1 = the correction factor SG1 × the reference value SD1. Here, the correction factor SG1 is a value that is changed according to the slope. The reference value SD1 is a constant value set to find the control gain G1.

When the vehicle is traveling with the automatic steering over a work field without inclination, that is, when the angle of the vehicle body <NUM> detected by the inclination detector device is zero, the parameter corrector portion 200a sets the correction factor SG1 to <NUM> to obtain the control gain G1. When the angle of the vehicle body <NUM> is within a predetermined range, the parameter corrector portion 200a also sets the correction factor SG1 to <NUM>. In other words, the parameter corrector portion 200a sets the control gain G1 corresponding to the level ground when the inclination of the vehicle body <NUM> is not large.

As shown in <FIG>, when steering is performed in the upward direction UP1 under a situation where the vehicle body <NUM> is traveling on an inclined field with the automatic steering (the angle of the vehicle body <NUM> detected by the tilt detector, that is, either the roll angle or the pitch angle is out of the predetermined range), the parameter corrector portion 200a can adjust the correction factor SG1. The control gain G1 is changed by increasing the correction factor SG1 from <NUM> and multiplying the increased correction factor SG1 by the reference value (constant) SD1. The parameter corrector portion 200a increases the correction factor SG1 as the inclination of the vehicle body <NUM> increases, that is, as the slope increases. In other words, the parameter corrector portion 200a increases the amount of correction of the control gain G1, that is, the amount of increase in the correction factor SG1, as the inclination of the vehicle body <NUM> in the upward direction increases.

When steering is performed in the downward direction DN1, the parameter corrector portion 200a changes the control gain G1 by decreasing the correction factor SG1 more than <NUM> and multiplying the decreased correction factor SG1 by a reference value (constant) SD1. The parameter corrector portion 200a decreases the correction factor SG1 as the inclination of the vehicle body <NUM> in the downward direction increases, that is, as the slope in the downward direction becomes stronger. In other words, the parameter corrector portion 200a increases the amount of correction of the control gain G1, that is, the amount of decrease of the correction factor SG1, as the inclination of the vehicle body <NUM> in the downward direction increases.

The steering angle calculator portion 200b calculates the steering angle of the steering device <NUM> to reduce the deviation based on the deviation between the scheduled line L2 and the vehicle body <NUM> (a positional deviation and an orientational deviation) and the parameters. In particular, the steering angle in the automatic steering is determined based on the position deviation, ΔL1, between the vehicle body position (a calculated vehicle body position W1 and a corrected vehicle position W3) and the scheduled traveling line L2, and the control gain G1 determined by the parameter corrector portion 200a. The steering angle calculator portion 200b determines the steering angle by, for example, multiplying the position deviation ΔL1 by the control gain G1. The steering angle calculator portion 200b may use the control gain G1 to determine the steering angle, and the method for calculating the steering angle is not limited thereto.

Alternatively, the steering angle calculator portion 200b determines the steering angle in the automatic steering based on the orientational deviation between the vehicle orientation and the scheduled traveling line L2 and the control gain G1 determined by the parameter corrector portion 200a. The steering angle calculator portion 200b obtains the steering angle by, for example, multiplying the orientational deviation by the control gain G1.

The steering controller portion 200c controls the steering device <NUM> based on the steering angle (calculated steering angle) calculated by the steering angle calculator portion 200b. As described above, the steering controller portion 200c controls the steering motor <NUM> so that when the tractor <NUM> is located on the left side with respect to the scheduled traveling line L2, the steering angle of the tractor <NUM> in the right direction is the calculated steering angle. The steering controller portion 200c controls the steering motor <NUM> so that the steering angle of the tractor <NUM> in the left direction of the tractor <NUM> is the arithmetic steering angle when the tractor <NUM> is located on the right side with respect to the scheduled traveling line L2, as described above.

As shown in <FIG>, when tractor <NUM> is steered in the downward direction, when steering is performed at a steering angle θ1 without correcting the control gain G1, the vehicle body <NUM> is subjected to an external force F in the lowland direction (slope direction) due to the slope, and the direction of traveling of the tractor <NUM> changes significantly, and the travel trajectory K changes quickly than that on a level ground. This causes the tractor <NUM> to move to a position where it overshoots the scheduled traveling line L2.

On the other hand, when the tractor <NUM> is steered in the downward direction, when the inclination of the vehicle body <NUM> obtained from the slope detector is greater than a predetermined value, the control gain G1 is changed by the parameter corrector portion 200a, so that the steering angle θ2 in the automatic steering, as shown in <FIG>, is becomes smaller than the steering angle θ1 in <FIG>. Thus, even when the traveling body <NUM> is subjected to an external force F in the lowland direction (inclination direction) due to the inclination, the change in the direction of traveling of the tractor <NUM> can be reduced, and the travel trajectory K can easily be made to match the scheduled traveling line L2.

As shown in <FIG>, when the tractor <NUM> is steered in the upward direction, when the steering is performed at a steering angle θ1 without correcting the control gain G1, the vehicle body <NUM> receives an external force F in the lowland (sloping) direction, so the change in the direction of traveling of the tractor <NUM> is small, and the travel trajectory K changes more gradual than that on level ground. Thus, the tractor <NUM> will remain in a position before the scheduled traveling line L2.

On the other hand, when the tractor <NUM> is steered in the upward direction, when the inclination of the vehicle body <NUM> obtained from the inclination detector device is greater than a predetermined value, the control gain G1 is changed by the parameter corrector portion 200a, so that the steering angle θ3 in the automatic steering, as shown in <FIG>, becomes larger than the steering angle θ1 in <FIG>. Thus, even when the traveling body <NUM> is subjected to an external force F in the lowland direction (inclination direction) due to the inclination, the change in the direction of traveling of the tractor <NUM> can be increased, and the travel trajectory K can easily be made to match the planned line L2.

In <FIG>, <FIG>, <FIG>, and <FIG>, the explanation was given for the width direction with respect to the vehicle body <NUM>. However, the same effect can be achieved when the vehicle body <NUM> is inclined with respect to the direction of traveling of the vehicle body <NUM>, whether it is uphill or downhill. For example, when the angle of inclination (pitch angle) of the vehicle body <NUM> with respect to the direction of travel is greater than a predetermined value compared to that of the level ground, and the angle is an upward slope as viewed from the vehicle body <NUM>, the control gain G1 is increased by the parameter corrector portion 200a, so that the steering angle θ3 in response to the pitch angle is greater than the steering angle θ1 set without correction. This makes it easier to change the direction of traveling of the vehicle body <NUM> when the vehicle body <NUM> is moving up the field compared to the changing on the level ground.

When the inclination angle (pitch angle) of the vehicle body <NUM> in the direction of travel is greater than the predetermined angle of travel (pitch angle) of the vehicle body <NUM> compared to the level ground, and the angle is a downward slope as viewed from the vehicle body <NUM>, the control gain G1 is reduced by the parameter corrector portion 200a, so that the steering angle θ2 in response to the pitch angle is smaller than the steering angle θ1 set without correction. Thus, when the vehicle body <NUM> is moving down the field, the direction of traveling of the vehicle body <NUM> can be changed more gradually compared to the changing on level ground.

The working vehicle <NUM> includes the steering device <NUM> to change the orientation of the vehicle body <NUM>, the inclination detector device to detect the inclination of the vehicle body <NUM>, a steering angle calculator portion 200b to calculate the steering angle of the steering device <NUM> to reduce the deviation based on the deviation between the planned line L2 and the vehicle body <NUM> and predetermined parameters, and the parameter corrector portion 200a to change a parameter to be applied to the steering angle calculator portion 200b based on the inclination of the vehicle body <NUM> detected by the inclination detector device. According to this configuration, when the vehicle body <NUM> is steered by the steering device <NUM>, which reduces the deviation between the scheduled traveling line L2 and the vehicle body <NUM>, the parameter to be applied to the steering angle calculator portion 200b is changed when the vehicle body <NUM> is inclined, so that the steering behavior of the vehicle body <NUM> can be changed in response to the inclination of the vehicle body <NUM>. For example, when the vehicle body <NUM> is traveling on a sloping ground, it can easily be made to travel along the scheduled traveling line L2.

The parameter corrector portion 200a changes the parameter when the inclination of the vehicle body <NUM> detected by the inclination detector device is greater than or equal to a predetermined threshold value. According to this configuration, the parameter is corrected under circumstances where the leaning of the vehicle body <NUM> affects the steering, that is, when the leaning of the vehicle body <NUM> is greater than or equal to the threshold, so that the vehicle body <NUM> can be driven along the scheduled traveling line L2 both on flat ground with little leaning and on sloping ground with large leaning.

The parameter corrector portion 200a corrects the parameter in a direction in which the steering angle increases when the inclination of the vehicle body <NUM> obtained from the inclination detector device indicates an upward direction, and corrects the parameter in a direction in which the steering angle decreases when the inclination of the vehicle body <NUM> indicates a downward direction. In this manner, for example, when the vehicle body <NUM> is traveling upward on a sloping ground, the parameter is corrected to increase the steering angle by correcting the parameter, thus eliminating the difficulty of the vehicle body <NUM> in turning due to the influence of the hill climbing. For example, when the vehicle body <NUM> traveling downward on a sloping ground, the parameter correction reduces the steering angle so that the vehicle body <NUM> does not turn too much due to the effect of the hill descending.

The parameter corrector portion 200a increases the amount of correction of the parameter in accordance with the increase in the inclination of the vehicle body <NUM> acquired from the inclination detector device. In this manner, the amount of correction can be increased in accordance with the slope, whether the vehicle body <NUM> is traveling up or down a slope, and the steering can be performed based on an inclination of the slope.

The parameter corrector portion 200a changes the control gain for calculating the steering angle of the steering device <NUM> as a parameter. According to this configuration, the steering angle can be easily obtained by changing the control gain SG1.

Other configurations of the second embodiment are configured in the same way as the first embodiment.

Next, the third embodiment will be described below.

Now, in order to perform the automatic steering after the setting of the reference traveling line L1, it is necessary to adjust the conditions for the automatic steering. For example, as shown in <FIG>, when, after turning the tractor <NUM> and before the automatic steering, the orientation of the tractor <NUM> in the direction of travel (vehicle orientation) F1 and the orientation of the travel reference line L1 (line orientation) F2 are significantly different, it is difficult to steer the tractor <NUM> along the planned travel line L2, which is parallel to the travel reference line L1, even when automatic steering is initiated. In such a case, the second controller device 60B determines that the conditions for the automatic steering are not satisfied.

The second controller device 60B makes a determination (judgment) whether or not to permit the automatic steering at least prior to the automatic steering, that is, based on the vehicle orientation F1 of the tractor <NUM> (vehicle body <NUM>) and the orientation of the reference traveling line L1 (line orientation) F2 in the manual steering. As shown in <FIG>, the second controller device 60B is provided with an orientation judgment portion (orientation judgment circuit) <NUM>. The orientation judgment portion <NUM> includes an electrical and electronic circuit in the second controller device 60B, a computer program stored in a CPU or the like. The orientation judgment portion <NUM> permits the automatic steering when the orientational difference ΔF between the vehicle orientation F1 and the line orientation F2 is within the judgment range G1, and does not permit the automatic steering when it is out of the judgment range G1.

<FIG> shows the relation between the orientational difference ΔF and the judgment range G1. As shown in <FIG>, the judgment range G1 is a range shown as negative on one side (left side) and positive on the other side (right side), centered on a reference traveling line <NUM> (reference traveling line <NUM>) where the vehicle orientation F1 and the line orientation F2 coincide (the reference traveling line <NUM> where the orientational difference ΔF is zero). The lower limit Gmin of the judgment range G1 is on the negative side, and the upper limit Gmax, is on the positive side. In <FIG>, the positive and negative in the judgment range G1 are set for convenience and are not limited to the examples described above.

When the inclination of the vehicle body <NUM> of the tractor <NUM> in the width direction of the tractor <NUM>, that is, when the roll angle of the vehicle body <NUM> is horizontal and the slope is zero (level ground), the lower limit Gmin and the upper limit Gmax of the judgment range G1 are predetermined values, and when the lower limit Gmin and the upper limit Gmax are considered in absolute values, they are the same values.

Thus, in a state where the tractor <NUM> is traveling in a horizontal state without leaning in the width direction, that is, in a state where the tractor <NUM> is traveling in a work field without inclining, when the orientational difference ΔF between the vehicle orientation F1 and the line orientation F2 is within the judgment range G1, the orientation judgment portion <NUM> permits the automatic steering, and when the orientational difference ΔF is out of the judgment range G1, the automatic steering is not permitted.

In the third embodiment described above, the second controller device 60B determines whether or not to permit the automatic steering based on the orientational difference ΔF and the judgment range G1. In addition, the second controller portion 60B changes the judgment range G1 used for the automatic steering according to the inclination of the vehicle body 3whnf the tractor <NUM> (vehicle body <NUM>) is traveling at an angle. The inclination of the vehicle body <NUM> is detected by an inclination detector device provided in the tractor <NUM> (vehicle body <NUM>). In the third embodiment, the inclination detector device is an inertial measurement device <NUM> having, for example, an acceleration sensor to detect acceleration, a gyroscope to detect angular velocity, and the like, which can detect the tractor <NUM> (vehicle body <NUM>). In addition, the inclination detector device may be a device including a plurality of positioning devices <NUM> (for example, a GPS compass, and the like), or it may be any other device.

As described above, when the inclination of the vehicle body <NUM> of the tractor <NUM> in the width direction of the tractor <NUM>, that is, the roll angle of the vehicle body <NUM> is horizontal and the inclination is zero, as shown in <FIG>, the orientation judgment portion <NUM> sets the judgment range G1 to the standard range ST1 and determines whether the automatic steering is permitted or not based on the standard range ST1.

As shown in <FIG>, when the tractor <NUM> (vehicle body <NUM>) is inclined in such a way that one side (left side) of the tractor <NUM> (vehicle body <NUM>) in the width direction is higher than the other side (right side) in the width direction, the second controller device 60B makes the lower limit Gmin of the judgment range G1 greater than the lower limit Gmin indicated in the standard range ST1. That is, in viewing the reference traveling line L1 from the tractor <NUM>, the lower limit Gmin of the judgment range G1 is increased when the reference traveling line L1 is high and the tractor <NUM> side is low falling to the right. In this case, the orientation judgment portion <NUM> determines whether or not to permit the automatic steering based on the judgment range G1 in which the lower limit Gmin is increased.

As shown in <FIG>, when tractor <NUM> is inclined downward to the right, when looking at the range of judgment range G1, the lower limit Gmin corresponding to the higher side (one side) of the tractor <NUM> is increased. In addition, as shown in <FIG>, it is preferred that the upper limit Gmax opposite to the lower limit Gmin in the judgment range Gmin is less than the upper limit Gmax of the standard range ST1. In other words, in cases where tractor <NUM> is inclined downward to the right, the upper value Gmax corresponding to the lower side (other side) of the tractor <NUM> is reduced.

As shown in <FIG>, when the tractor <NUM> (vehicle body <NUM>) is inclined so that one side (left side) is lower than the other side (right side) in the width direction, as shown in <FIG>, the second controller device 60B makes the upper limit Gmax of the judgment range G1 greater than the upper limit Gmax indicated in the standard range ST1. That is, in viewing the reference traveling line L1 from the tractor <NUM>, the upper limit value Gmax of the judgment range G1 is increased when the reference traveling line L1 is high and the tractor <NUM> side is low falling to the left. In this case, the orientation judgment portion <NUM> determines whether the automatic steering is permitted or not based on the judgment range G1 in which the upper limit value Gmax is increased.

As shown in <FIG>, when tractor <NUM> is tilted downward to the left, the upper limit Gmax corresponding to the higher side of tractor <NUM> (right side) is increased when looking at the range of judgment range G1. In addition, as shown in <FIG>, it is preferable to make the lower limit Gmin opposite to the upper limit Gmax of the judgment range G1 smaller than the lower limit Gmin of the standard range ST1. In other words, when tractor <NUM> is inclined downward to the left, the lower limit Gmin corresponding to the lower side (one side) of the tractor <NUM> is reduced.

In changing the lower limit Gmin and upper limit Gmax of the judgment range G1, the second controller device 60B increases the lower limit Gmin and the upper limit Gmax according to the degree of the slope (inclination magnitude) of the vehicle body of the tractor <NUM> in the width direction of the vehicle body <NUM> (roll angle of the vehicle body <NUM>). That is, the second controller device 60B increases the lower limit Gmin and upper limit Gmax with respect to the standard range ST1 when the inclination amount is large, and decreases the lower limit Gmin and upper limit Gmax with respect to the standard range ST1 when the inclination amount is small.

The automatic steering controller portion <NUM> controls the steering device <NUM> as described above when the start of the automatic steering is switched by the steering changeover switch <NUM> when the start of the automatic steering is determined to be permitted by the orientation judgment portion <NUM>.

The display device <NUM> is capable of displaying that the start of the automatic steering has been determined to be permitted by the orientation judgment portion <NUM>.

In the third embodiment, for example, the fourth icon portion 66D is displayed when the setting mode is valid and the completion of the setting of the reference traveling line L1, and the orientation judgment portion <NUM> of the second controller device 60B has given permission for the automatic steering. By looking at the fourth icon portion 66D, the operator can see that the automatic steering is permitted. The operator can then start the automatic steering by operating the steering changeover switch <NUM>.

In the third embodiment described above, the condition for permitting the automatic steering is that the orientational difference ΔF is within a predetermined range, but a condition may be added that the steering angle of the steering device <NUM> is within a predetermined range. That is, in a situation where the tractor <NUM> (vehicle body <NUM>) is being steered by the manual steering, the second controller device 60B permits the automatic steering with respect to the orientation (first permit) when the orientational difference ΔF is within a predetermined range, and permits the automatic steering with respect to the steering (second permit) when the steering angle θ of the steering device <NUM> is within a predetermined range. The second controller device 60B then starts the automatic steering when the first and second permissions are issued and the operator switches to the start of the automatic steering.

The working vehicle <NUM> includes the steering device <NUM> having the steering handle <NUM>, the vehicle body <NUM> configured to travel either in the manual steering with the steering handle <NUM> or in the automatic steering of the steering handle <NUM> based on the reference traveling line L1, the positioning device <NUM> configured to detect the orientation F1 of the vehicle body <NUM>, the inclination detector device to detect the inclination of the vehicle body <NUM>, and the controller device 60B configured to permit the automatic steering by the steering device <NUM> when the difference ΔF between the orientation F1 of the vehicle body <NUM> detected by the positioning device <NUM> and the orientation F2 of the reference traveling line L1 is within the judgment range G and to perform the automatic steering by the steering device when permitting the automatic steering. The controller device 60B changes the judgment range depending on the inclination of the vehicle body <NUM> detected by the inclination detector device. According to this configuration, in either a case where the traveling orientation of the working vehicle <NUM> is an uphill direction (the vehicle orientation is oriented in the uphill direction) or a case where the traveling orientation of the working vehicle <NUM> is a down-hill direction (the vehicle orientation is oriented in the down-hill direction), it is possible to appropriately start the automatic steering in response to the inclination in operating the working vehicle <NUM> (vehicle body <NUM>) on a slope. That is, the traveling can be stable in switching the steering from the manual steering to the automatic steering even on the slope.

The controller device 60B changes the lower limit Gmin of the judgment range G1 in accordance with the inclination of the vehicle body <NUM>, when the vehicle body <NUM> is inclined such that one side of the vehicle body <NUM> in the width direction is higher than the other side in the width direction. The controller device 60B also changes the upper limit Gmax of the judgment range G1 in accordance with the inclination of the vehicle body <NUM> when the vehicle body <NUM> is inclined such that one side of the vehicle body <NUM> in the width direction is lower than the other side in the width direction.

According to this configuration, when the working vehicle <NUM> (vehicle body <NUM>) travels on a slope, the lower limit value Gmin corresponding to the higher side (one side) of the tractor <NUM> can be increased and the upper limit value Gmax corresponding to the higher side (other side) of the tractor <NUM> can be increased. In other words, in the judgment range G1, the values of the higher side of the working vehicle <NUM> (vehicle body <NUM>) (the upper limit Gmax and the lower limit Gmin) are increased. As a result, when the working vehicle <NUM> is manually steered to the higher side and then automatically steered (when the tractor <NUM> is manually steered in the uphill direction and then automatically steered), it is possible to increase the difference in orientation between the vehicle orientation and the line orientation before switching to the automatic steering. Thus, when the working vehicle <NUM> starts the automatic steering in the uphill direction, the vehicle will be able to travel consistently on a slope just after switching to the automatic steering.

As shown in <FIG>, when the tractor <NUM> inclines so that the other side (right side) of the tractor <NUM> is lower than the one side (left side), the controller device 60B makes the upper limit value Gmax corresponding to the other side (right side) smaller than the predetermined standard range ST1. In addition, as shown in <FIG>, when the tractor <NUM> inclines such that one side (left side) of the tractor <NUM> is lower than the other side (right side), the controller device 60B makes the lower limit Gmin corresponding to one side (left side) less than the predetermined standard range ST1.

According to this configuration, when the working vehicle <NUM> is manually steered to the lower side and then automatically steered (when the tractor <NUM> is manually steered in the downhill direction and then automatically steered), it is possible to reduce the difference in orientation between the vehicle orientation and the line orientation before switching to the automatic steering. Thus, when the working vehicle <NUM> starts the automatic steering in the downhill direction, the vehicle can travel consistently on a slope just after switching to the automatic steering.

The working vehicle <NUM> includes the steering changeover switch <NUM> to be switched between the start and end of the automatic steering, and the controller device 60B starts the automatic steering by the steering device <NUM> when the steering changeover switch <NUM> is switched to the start of the automatic steering under the condition where the automatic steering is permitted. According to this configuration, the steering changeover switch <NUM> allows the operator to command the start of the automatic steering at the time when the operator needs to perform the start of the automatic steering.

The working vehicle <NUM> includes the display device <NUM> that displays that the orientational difference ΔF between the orientation of the vehicle body <NUM> detected by the positioning device <NUM> and the orientation F2 of the reference traveling line L1 is within the judgment range G1. According to this configuration, the operator can easily understand by looking at the display device <NUM> that the vehicle is in a state where the automatic steering can be started.

The working vehicle <NUM> includes the reference traveling line setter switch that sets the position of the vehicle body <NUM> detected by the positioning device <NUM> to the start and end positions of the reference traveling line L1. According to this configuration, the setting of the reference traveling line L1 can be easily performed.

Now, the display device <NUM> is capable of displaying the line orientation F2 and vehicle orientation F1 of the reference traveling line L1. As shown in <FIG>, when a predetermined action is performed on the display device <NUM>, the display device <NUM> displays an orientation screen M2. The orientation screen M2 includes a line orientation display portion <NUM> and a vehicle orientation display portion <NUM>.

The line orientation display portion <NUM> is configured to indicate the line orientation F2 of the reference traveling line L1 and includes the line display portion 130a and the mark portion 130b. The line display portion 130a representing the reference traveling line L1 itself with a line diagram and the like, and extends from the bottom to the top on a field <NUM> set in the orientation screen M2. The mark portion 130b indicates a direction of the reference traveling line L1, for example, is arranged on the upper portion of the end portion <NUM> of the line display portion 130a in the field <NUM>. In the mark portion 130b, the vertex <NUM> of the triangle points to the end portion <NUM> of the line display portion 130a.

The vehicle orientation display portion <NUM> includes an orientation indicator portion <NUM> that points to a direction of the vehicle body <NUM> (vehicle orientation F1). The orientation indicator portion <NUM> points to a direction in which the body bearing F1 faces with respect to the line orientation F2.

The orientation indicator portion <NUM> includes, for example, a graphic such as an arrow, and the orientation indicator portion <NUM> moves to one side or the other of the line display portion 130a with respect to the origin O1 set on the line display portion 130a.

The vehicle orientation display portion <NUM> also includes the vehicle body display portion <NUM>, which shows the tractor <NUM> (vehicle body <NUM>) in graphic form. The vehicle body display portion <NUM>, like the orientation indicator portion <NUM>, changes position (display position) according to the orientation around the origin O1. In detail, the orientation indicator portion <NUM> is arranged in front of the vehicle body display portion <NUM> (on the front of the tractor <NUM>), and the vehicle body display portion <NUM> and the orientation indicator portion <NUM> simultaneously oscillate according to the vehicle orientation F1.

As shown in <FIG>, when the vehicle orientation F1 is in the same orientation as the line orientation F2, the tip portion 141a of the orientation indicator portion <NUM> and the end portion <NUM> of the mark portion 130b are opposite each other. Also, as shown in <FIG>, when the vehicle orientation F1 is displaced to the left with respect to the line orientation F2, the tip portion 141a of the orientation indicator portion <NUM> is located to the left of the line display portion 130a. As shown in <FIG>, when the vehicle orientation F1 is displaced to the right with respect to the line orientation F2, the tip portion 141a of the orientation indicator portion <NUM> is located to the right of the line display portion 130a.

According to the above configuration, by checking the relative position of the tip of the orientation indicator portion 141a and the mark portion 130b or the line display portion 130a, the operator can determine the extent to which the vehicle orientation F1 deviates from the line orientation F2.

As shown in <FIG>, an orientation scale portion <NUM> may be displayed on the orientation screen M2. The orientation scale portion <NUM> is a scale in which the line orientation F2 of the reference traveling line L1 is the reference point O2, and the orientational difference ΔF (a value indicating the orientation) increases or decreases according to the distance from the reference point O2. That is, the orientation scale portion <NUM> includes a semicircular shape with a scale line 145a assigned to the orientational difference ΔF at predetermined intervals along the circumference of the semicircular shape. At the reference point O2 of the orientation scale portion <NUM>, the end portion <NUM> of the mark portion 130b is pointed to. In addition, as shown in <FIG>, the orientation scale portion <NUM> shows a judgment range G1. That is, the plurality of scale lines 145a on the orientation scale portion <NUM> are colored with at least two colors separately, and the plurality of scale lines 145a near the reference point O2 are colored with a color indicating that the value is within the judgment range G1 (a color within the range), and the plurality of scale lines 145a at a distance from the reference point O2 are colored with a value out of the judgment range G1 (a color out of the range) to indicate that a value is out of the judgment range G1. As described above, when the judgment range G1 is changed in accordance with the inclination of the vehicle body <NUM>, the plurality of scale lines 145a are colored to correspond to in-range and out-of-range of the changed judgment range G1.

The orientation indicator portion <NUM> is arranged inside the orientation scale portion <NUM> and points the vehicle orientation F1 to the orientation scale portion <NUM>. The orientation indicator portion <NUM> has a different display configuration when the orientational difference ΔF between the line orientation F2 and the vehicle orientation F1 is within a predetermined range (within the judgment range G1) or when the orientational difference ΔF is out of the predetermined range (outside the judgment range G1). As shown in <FIG>, the orientation indicator portion <NUM> is colored the same color as the in-range color of the orientation scale portion <NUM> when the orientational difference ΔF is within the predetermined range (within the judgment range G1). As shown in <FIG> and <FIG>, the orientation indicator portion <NUM> is colored the same color as the color out of range of the orientation scale portion <NUM> when the orientational difference ΔF is out of the predetermined range (out of the judgment range G1).

When the orientational difference ΔF is within a predetermined range, the display device <NUM> displays, on the orientation screen M2, a steering wheel display <NUM> showing a graphic of the steering wheel <NUM>, and displays a graphic <NUM> indicating that the automatic steering can be started.

The working vehicle <NUM> includes the steering handle <NUM>, the traveling body <NUM> configured to travel in either in the manual steering by the steering handle <NUM> or in the automatic steering of the steering handle <NUM> based on the reference traveling line L1, the line orientation display portion <NUM> indicating the orientation F2 of the reference traveling line L1, and the display device <NUM> having the vehicle orientation display portion <NUM> indicating the orientation F1 of the vehicle body <NUM>. According to this configuration, the display device <NUM> allows the user to easily determine which orientation the working vehicle <NUM> (vehicle body <NUM>) is facing with respect to the orientation F2 of the reference traveling line L1.

The line orientation display portion <NUM> includes the line display portion 130a which indicates the reference traveling line L1, and the mark portion 130b which indicates the orientation F2 of the reference traveling line L1. According to this configuration, even when the operator is not able to know exactly what orientation the orientation F2 of the reference traveling line L1 is in a work field or other work area, the orientation F2 of the reference traveling line L1 can be easily ascertained by looking at the line display portion 130a and the mark portion 130b displayed on the display device <NUM>.

The vehicle orientation display portion <NUM> includes the orientation indicator portion <NUM> which points to the orientation F1 of the vehicle body <NUM>, and the vehicle body display portion <NUM> which shows the vehicle body <NUM> whose display position changes according to the orientation F1 of the vehicle body <NUM>. Accordingly, even when the operator is not able to accurately determine the orientation F1 of the vehicle body <NUM> in the work field, the orientation F1 of the vehicle body <NUM> can be easily ascertained by looking at the orientation indicator portion <NUM> and the vehicle body display <NUM> displayed on the display device <NUM>.

The display device <NUM> has an orientation scale portion <NUM> which has the orientation F2 of the reference traveling line L1 as the reference point and whose value indicating the orientation increases or decreases depending on the distance from the reference point. The line orientation display portion <NUM> includes, in the reference point, the mark portion 130b indicating the orientation of the reference traveling line. According to this configuration, when looking at the scale portion <NUM>, an operator can easily know which direction the orientation F2 of the reference traveling line L1 is with respect to the vehicle body <NUM>.

The vehicle orientation display portion <NUM> includes the orientation indicator portion <NUM> that points to the orientation F1 of the vehicle body <NUM>, and the orientation indicator portion <NUM> points the orientation F1 of the vehicle body <NUM> to the orientation scale portion <NUM>. According to this configuration, the extent to which the orientation F1 of the vehicle body <NUM> is out of alignment with the reference traveling line L1 can be easily ascertained by looking at the orientation indicator portion <NUM> indicated on the orientation scale portion <NUM>.

The vehicle orientation display <NUM> has different display formats alternately displayed when the orientational difference ΔF between the orientation F2 of the reference traveling line L1 and the orientation F1 of the vehicle body <NUM> is within a predetermined range and when the orientational difference ΔF is out of the predetermined range. This makes it easy for the operator to know whether or not the difference in the orientation ΔF is within the predetermined range.

The working vehicle includes the controller device 60B configured to permit the automatic steering when the orientation difference ΔF between the orientation F2 of the reference traveling line L1 and the orientation F1 of the vehicle body <NUM> is within a predetermined range. This makes it easy to switch the steering from the manual steering to the automatic steering.

Claim 1:
A working vehicle (<NUM>), comprising:
a steering device (<NUM>) having a steering handle (<NUM>);
a vehicle body (<NUM>) configured to travel with either manual steering by the steering handle (<NUM>) or automatic steering of the steering handle (<NUM>) based on a traveling-reference line (L1);
a positioning device (<NUM>) configured to detect an orientation (F1) of the vehicle body (<NUM>);
a display device (<NUM>) including: a line orientation display portion (<NUM>) configured to indicate an orientation (F2) of the traveling reference line (L1); a vehicle orientation display portion (<NUM>) configured to indicate the orientation (F1) of the vehicle body (<NUM>); and an orientation scale portion (<NUM>) having a reference point (O2) that coincides with the orientation (F2) of the traveling reference line (L1) and being configured to increase and decrease a value indicating the orientation (F2) of the traveling reference line (L1) based on a distance from the reference point (O2); and
a controller device (60B) configured to permit the automatic steering by the steering device (<NUM>) when an orientational difference (ΔF) which is a difference between the orientation (F1) of the vehicle body (<NUM>) detected by the positioning device (<NUM>) and the orientation (F2) of the traveling reference line (L1) is within a judgment range (G1) and to perform the automatic steering by the steering device (<NUM>) when permitting the automatic steering, the working vehicle (<NUM>) being characterized by comprising:
an inclination detector device (<NUM>) configured to detect an inclination of the vehicle body (<NUM>) in a width direction, wherein
the orientation scale portion (<NUM>) is configured to show the judgment range (G1),
the controller device (60B) is configured to change the judgment range (G1) in accordance with the inclination of the vehicle body (<NUM>) in the width direction detected by the inclination detector device (<NUM>), and
the orientation scale portion (<NUM>) is configured to, when the judgment range (G1) is changed in accordance with the inclination of the vehicle body (<NUM>) in the width direction, show the changed judgment range (G1).