Patent Description:
Conventionally, a working machine disclosed in Patent document <NUM> includes a machine body capable of traveling, a working device mounted on the machine body, a position detecting device to detect the position of a machine body, and a control device to control the machine body on the basis of the position of the machine body detected by the position detecting device and a planned travel route. <CIT> describes a control apparatus for an automatic traveling vehicle including a position sensor and circuitry. The position sensor is to detect a vehicle position of the automatic traveling vehicle. The circuitry is configured to control the automatic traveling vehicle to travel along a first route, a first turn route connected to the first route, a straight route connected to the first turn route, a second turn route connected to the straight route, and a second route connected to the second turn route in this order, and to calculate the straight route extending from a reference point on the first turn route to the second turn route such that the straight route is tangent to the second turn route. <CIT> describes a method and apparatus for automatically controlling ground speed of a work vehicle. The apparatus includes a speed sensor generating a vehicle speed signal, the speed sensor operatively connected to a controller. A traction device angle sensor generates an angle signal which represents an angle of the traction device with respect to an axis of the work vehicle, wherein the traction device angle sensor operatively connected to the controller.

The working machine of Patent document <NUM> is capable of traveling along a planned travel route.

However, the control device performs control so that the deviation between the machine body and the planned travel route is eliminated both in the case where travel accuracy is required given the type of work done by the working device and in the case where the travel accuracy is not required given the type of the work. Therefore, work efficiency may decrease in the case of work for which accuracy is not required.

The present invention was made in order to solve such an issue of the conventional technique, and an object thereof is to provide a working machine that is capable of efficiently traveling according to work accuracy.

Particular embodiments of the claimed invention are defined by the dependent claims.

The above-described working machine is capable of efficiently traveling according to work accuracy.

The following description discusses an embodiment of the present invention with reference to drawings.

First, a working machine <NUM> is discussed. The working machine <NUM> includes a working device <NUM> to do work, and is, for example, an agricultural machine such as a tractor, a combine, or a rice transplanter. The present embodiment is discussed based on the assumption that the working vehicle <NUM> is a tractor. As illustrated in <FIG>, the working machine <NUM> includes a machine body (travel vehicle) <NUM> capable of traveling, a prime mover <NUM>, a transmission <NUM>, and the working device <NUM>. The machine body <NUM> is provided with an operator's seat <NUM>. In the following description, the front of the working machine <NUM> (as indicated by arrow A1 in <FIG>) as seen from an operator seated on the operator's seat <NUM> is "front", the rear of the working machine <NUM> (as indicated by arrow A2 in <FIG>) as seen from the operator is "rear", the left side of the working machine <NUM> (near side in <FIG>) as seen from the operator is "left", and the right side of the working machine <NUM> (far side in <FIG>) as seen from the operator is "right".

The machine body <NUM> includes a traveling device <NUM>. The traveling device <NUM> includes wheels which rotate (front wheel(s) 7F and rear wheel(s) 7R). The front wheels 7F may be tire-shaped wheels and may be crawler-shaped wheels. The rear wheels 7R also may be tire-shaped wheels and may be crawler-shaped wheels.

The prime mover <NUM> is a diesel engine, an electric motor, and/or the like. The transmission <NUM> is capable of changing driving forces for the traveling device <NUM> by changing speed stages and switching the traveling state of the traveling device <NUM> between forward and rearward traveling states. In the present embodiment, the transmission <NUM> is a continuously variable transmission, in particular, a hydraulic mechanical transmission (HMT). The machine body <NUM> includes an output shaft (PTO shaft) <NUM> which transmits power from the prime mover <NUM>. The output shaft <NUM> projects rearward from the rear of the machine body <NUM>.

Furthermore, as illustrated in <FIG>, the machine body <NUM> has a raising/lowering device <NUM> to which the working device <NUM> can be detachably attached and which is capable of raising and lowering the working device <NUM>. Specifically, the machine body <NUM> is provided with, at the rear thereof, the raising/lowering device <NUM> composed of a three-point linkage or the like. This makes it possible to link the working device <NUM> to the machine body <NUM>. By linking the working device <NUM> to the raising/lowering device <NUM>, it is possible to allow the machine body <NUM> to tow the working device <NUM>.

The working device <NUM> is mounted on the machine body <NUM> via, for example, the raising/lowering device <NUM>. The working device <NUM> is a digger for digging potatoes and/or carrots, a spreader such as a fertilizer spreader (fertilizing device) for spreading fertilizer or an agricultural chemical spreader for spreading agricultural chemicals, a seeder for seeding on an agricultural field, a harvester for harvesting, a digger for mowing grass or the like, a tedder for tedding grass or the like, a rake for raking grass or the like, a baler for baling grass or the like, a ground implement which does work against an agricultural field, or the like. The ground implement encompasses a stubble cultivator for stubble cultivation, a harrow for puddling, a cultivator (rotary cultivator) for cultivating work, and the like.

As illustrated in <FIG>, the working machine <NUM> includes a steering unit <NUM>. The steering unit <NUM> includes a steering wheel 11a, a rotation shaft (steering shaft) 11b which rotates as the steering wheel 11a rotates, and an assist mechanism (power steering mechanism) 11c to assist steering performed using the steering wheel 11a. The assist mechanism 11c includes a hydraulic pump <NUM>, a control valve <NUM> supplied with hydraulic fluid discharged from the hydraulic pump <NUM>, and a steering cylinder <NUM> which is caused to function by the control valve <NUM>. The control valve <NUM> is a solenoid valve which functions according to a control signal. The control valve <NUM> is, for example, a three-way switching valve which achieves multi-position switching by movement of a spool or the like. The positions of the control valve <NUM> can also be switched by steering by the rotation shaft 11b. The steering cylinder <NUM> is connected to arms (knuckle arms) <NUM> which change the orientation of the front wheels 7F.

Therefore, upon operation of the steering wheel 11a, the position and the degree of opening of the control valve <NUM> change according to the steering wheel 11a, and the steering cylinder <NUM> extends or retracts leftward or rightward according to the position and the degree of opening of the control valve <NUM>, making it possible to change the steering direction of the front wheels 7F. Note that the foregoing steering unit <NUM> is an example, and the foregoing configuration does not imply limitation.

The raising/lowering device <NUM> is described in detail. As illustrated in <FIG>, the raising/lowering device <NUM> includes lift arms 8a, lower links 8b, a top link 8c, lift rods 8d, and lift cylinders 8e, and is capable of raising and lowering the working device <NUM>. As illustrated in <FIG>, a front end of each lift arm 8a is supported on an upper rear portion of a case (transmission case) housing the transmission <NUM> such that the lift arm 8a is swingable up and down. The lift arm 8a is driven by a corresponding lift cylinder 8e to swing (raised or lowered). The lift cylinder 8e is composed of a hydraulic cylinder. The lift cylinder 8e is connected to the hydraulic pump12 via the control valve <NUM>. The control valve <NUM> is a solenoid valve or the like to cause the lift cylinder 8e to extend and retract.

As illustrated in <FIG>, a front end of each lower link 8b is supported on a lower rear portion of the transmission <NUM> such that the lower link 8b is swingable up and down. A front end of the top link 8c is supported, at a position higher than the lower link 8b, on a rear portion of the transmission <NUM> such that the top link 8c is swingable up and down. Each lift rod 8d connects a corresponding lift arm 8a and a corresponding lower link 8b. The working device <NUM> is linked to rear portions of the lower links 8b and the top link 8c. When the lift cylinders 8e are driven (extend or retract), the lift arms 8a ascend or descend, and the lower links 8b connected to the lift arms 8a via the lift rods 8d also ascend or descend. With this, the raising/lowering device <NUM> is capable of switching between a non-working position in which the working device <NUM> is in a raised position and a working position in which the working device <NUM> is in a lowered position, and the working device <NUM> swings up or down (raised or lowered) about front portions of the lower links 8b.

As illustrated in <FIG>, the working machine <NUM> includes a display device <NUM>. The display device <NUM> includes a display unit <NUM> composed of a liquid crystal panel, a touchscreen, or some other panel, and a storage device <NUM>. The display unit <NUM> is configured to display not only information to assist the working machine <NUM> in traveling but also various types of information regarding the working machine <NUM>. The storage device <NUM> is a nonvolatile memory and/or the like, and stores, for example, information to be displayed on the display unit <NUM>. Furthermore, the display device <NUM> is connected to apparatus(es) of the working machine <NUM> communicably in a wired or wireless manner.

As illustrated in <FIG>, the working machine <NUM> is capable of performing automatic travel according to a predetermined planned travel route L and raising and lowering the working device <NUM> via the raising/lowering device <NUM>.

As illustrated in <FIG>, the working machine <NUM> includes a position detecting device <NUM>. The position detecting device <NUM> is a device to detect the position of the machine body <NUM>. In the present embodiment, the position detecting device <NUM> is, for example, a positioning device. The position detecting device <NUM> is capable of detecting the position thereof (measured position information including latitude and longitude) by a satellite positioning system (positioning satellites G) such as D-GPS, GPS, GLONASS, BeiDou, Galileo, and/or Michibiki. Specifically, the position detecting device <NUM> receives satellite signals (positions of positioning satellites G, time of transmission, correction information, and/or the like) from the positioning satellites G, and detects the position (e.g., latitude and longitude) of the working machine <NUM> (machine body <NUM>), i.e., a machine body position W1, on the basis of the satellite signals. As illustrated in <FIG>, the position detecting device <NUM> includes a receiver <NUM> and an inertial measurement unit (IMU) <NUM>. The receiver <NUM> is a device which includes an antenna and/or the like and which receives satellite signals from the positioning satellites G, and is attached to the machine body <NUM> independently of the inertial measurement unit <NUM>. In the present embodiment, the receiver <NUM> is attached to an upper portion of a cabin (protection mechanism) <NUM> provided on the machine body <NUM>. Note that the location at which the receiver <NUM> is attached is not limited to that described above, and may be a central portion of a hood. In the case where a ROPS is provided on the machine body <NUM>, the receiver <NUM> may be attached to an upper portion of the ROPS.

The inertial measurement unit <NUM> includes an acceleration sensor to detect the acceleration α of the machine body <NUM>, a gyroscope sensor to detect the angular velocity of the machine body <NUM>, and/or the like. The inertial measurement unit <NUM> is provided on the machine body <NUM>, for example, below the operator's seat <NUM>, and is capable of detecting the roll angle, pitch angle, yaw angle, and/or the like of the machine body <NUM>.

Note that, although the position detecting device <NUM> in the present embodiment is a position detecting device <NUM> that detects the position of the machine body <NUM> on the basis of satellite signals, the position detecting device <NUM> is not limited to the configuration as described above, provided that the position detecting device <NUM> is capable of detecting the position of the machine body <NUM>. The position detecting device <NUM> may be one that detects the position of the machine body <NUM> on the basis of the acceleration α detected by the inertial measurement unit <NUM> and prescribed position information.

As illustrated in <FIG>, the working machine <NUM> includes a control device <NUM> and a storage unit <NUM>. The control device <NUM> is a device to control a traveling system of the working machine <NUM>, control a working system of the working machine <NUM>, and/or the like. The storage unit <NUM> is a nonvolatile memory and/or the like, and stores various types of information regarding control by the control device <NUM>.

As illustrated in <FIG>, the steering unit <NUM> includes an auto-steerer <NUM>. The auto-steerer <NUM> is a mechanism to perform automatic steering of the machine body <NUM>, and automatically steers the machine body <NUM> on the basis of a planned travel route L and a machine body position W1 detected by the position detecting device <NUM>. The auto-steerer <NUM> includes a steering motor 17a and a gear mechanism 17b. The steering motor 17a is a motor whose direction of rotation, speed of rotation, angle of rotation, and/or the like can be controlled on the basis of the machine body position W1. The gear mechanism 17b includes a gear which is provided on the rotation shaft 11b and which rotates together with the rotation shaft 11b, and a gear which is provided on the rotation shaft 11b of the steering motor 17a and which rotates together with the rotation shaft 11b. As the rotation shaft 11b of the steering motor 17a rotates, the rotation shaft 11b automatically rotates (pivots) via the gear mechanism 17b, making it possible to change the steering direction of the front wheels 7F so that the machine body position W1 matches the planned travel route L.

As illustrated in <FIG>, the control device <NUM> includes an automatic travel control unit 60a to control the machine body <NUM> on the basis of the machine body position W1 detected by the position detecting device <NUM> and the planned travel route L, that is, control the automatic travel of the working machine <NUM>. The automatic travel control unit 60a is composed of electrical/electronic circuit(s) in the control device <NUM>, program(s) stored in a CPU and/or the like in the control device <NUM>, and/or the like. The automatic travel control unit 60a is capable of controlling the speed stage of the transmission <NUM>, the rotation speed of the prime mover <NUM>, the auto-steerer <NUM>, and the like, and controls the automatic travel of the machine body <NUM> on the basis of the machine body position W1 detected by the position detecting device <NUM> and the planned travel route L.

The automatic travel control unit 60a controls, after the start of automatic travel, the steering motor 17a so that the machine body <NUM> travels along the planned travel route L. The automatic travel control unit 60a, after the start of automatic travel, automatically changes the speed stage of the transmission <NUM>, the rotation speed of the prime mover <NUM>, and/or the like to control the vehicle speed (travel speed) of the working machine <NUM>.

As illustrated in <FIG>, the planned travel route L includes a plurality of straight sections L1 on which the machine body <NUM> travels straight. The planned travel route L also includes connecting section(s) L2 each of which connects an end point Lb of one of the plurality of straight sections L1 and a start point La of another of the plurality of straight sections L1. In the present embodiment, the connecting sections L2 are turn sections on which the machine body <NUM> turns. The automatic travel control unit 60a, after the start of automatic travel, performs control so that different travel speeds are used in the straight sections L1 and the turn sections L2, respectively. For example, in the straight sections L1, the automatic travel control unit 60a sets the travel speed to a speed v1. On the other hand, in the turn sections L2, the automatic travel control unit 60a sets the travel speed to a speed v2 that is lower than the speed v1 (v2 is greater than v1). Note that any of the straight sections L1 may be divided into a plurality of segments and the automatic travel control unit 60a may set different travel speeds in the respective segments. The control of the travel speed is not limited to the above-described configuration.

Furthermore, the automatic travel control unit 60a, after the start of automatic travel, controls the raising/lowering device <NUM> to be in different positions in the straight sections L1 and the turn sections L2, respectively. For example, in the straight sections L1, the automatic travel control unit 60a sets the raising/lowering device <NUM> to be in a working position. On the other hand, in the turn sections L2, the automatic travel control unit 60a sets the raising/lowering device <NUM> to be in a non-working position.

As illustrated in <FIG>, under the conditions in which the working machine <NUM> is performing automatic travel, the automatic travel control unit 60a performs control so that the machine body <NUM> travels along the planned travel route L. That is, if the deviation between the machine body <NUM> and the planned travel route L is less than a predetermined set value, the automatic travel control unit 60a maintains the angle of rotation of the rotation shaft 11b. If the deviation between the machine body <NUM> and the planned travel route L is equal to or greater than the set value, the automatic travel control unit 60a causes the rotation shaft 11b to rotate so that the deviation is zero.

Specifically, if the deviation (deviation in position) between the machine body position W1 and the planned travel route L is less than a predetermined set value, the automatic travel control unit 60a maintains the angle of rotation of the rotation shaft 11b. On the contrary, if the deviation in position between the machine body position W1 and the planned travel route L is equal to or greater than the set value and the working machine <NUM> is positioned leftward of the planned travel route L, the automatic travel control unit 60a causes the rotation shaft 11b to rotate so that the working machine <NUM> is steered right. If the deviation in position between the machine body position W1 and the planned travel route L is equal to or greater than the set value and the working machine <NUM> is positioned rightward of the planned travel route L, the automatic travel control unit 60a causes the rotation shaft 11b to rotate so that the working machine <NUM> is steered left.

Note that, although the angle of steering by the steering unit <NUM> is changed on the basis of the deviation in position between the machine body position W1 and the planned travel route L in the above embodiment, the automatic travel control unit 60a may, in the case where the direction of the planned travel route L and the travel direction of the working machine <NUM> (machine body <NUM>) (machine body heading direction) F1 differ from each other, i.e., in the case where an angle (deviation in direction) θg of the machine body heading direction F1 to the planned travel route L is equal to or greater than a set value, set the angle of steering so that the angle θg is zero (the machine body heading direction F1 matches the direction of the planned travel route L). The automatic travel control unit 60a may set the final angle of steering for the automatic travel on the basis of an angle of steering determined based on the deviation (deviation in position) and an angle of steering determined based on directions (deviation in direction). Settings of the angle of steering in automatic travel in the above-described embodiment are examples, and do not imply any limitation.

As illustrated in <FIG>, the automatic travel control unit 60a causes the machine body <NUM> to perform a recovery movement such as to make the deviation between the position of the machine body <NUM> (machine body position) W1 detected by the position detecting device <NUM> and the planned travel route L less than a predetermined threshold when the machine body <NUM> is at a start point La of a straight section L1 or is about to enter the start point La of the straight section L1. Specifically, the automatic travel control unit 60a causes the machine body <NUM> to travel rearward and forward to make a three-point turn (hereinafter referred to as a three-point-turn movement) to make the deviation less than the threshold at a position short of the start point La of the straight section L1 or at the start point La. In the present embodiment, if the angle (deviation in direction) θg of the machine body heading direction F1 to the straight section L1 is equal to or greater than the threshold, the automatic travel control unit 60a causes the machine body <NUM> to perform a three-point-turn movement so that the angle θg is zero (the machine body heading direction F1 matches the direction of the planned travel route L).

Specifically, when the machine body position W1 is located at a position short of the start point La of the straight section L1 or located at the start point La and the deviation in direction θg is equal to or greater than a threshold, as illustrated in the middle part of <FIG>, the automatic travel control unit 60a sets the angle of steering so that the deviation in direction θg approaches zero and switches the transmission <NUM> to rearward travel to cause the machine body <NUM> to travel a predetermined distance rearward (short rearward travel).

Furthermore, after causing the machine body <NUM> to travel a predetermined distance rearward, the automatic travel control unit 60a sets the angle of steering so that the deviation in direction θg further approaches zero, and, as illustrated in the lower part of <FIG>, switches the transmission <NUM> to forward travel and causes the machine body <NUM> to travel a predetermined distance forward to move to the position short of the start point La of the straight section L1 or to the start point La (short forward travel). The automatic travel control unit 60a repeats the short rearward travel and the short forward travel until the deviation in direction θg from the straight section L1 is less than the threshold.

A flow of the three-point-turn movement of the machine body <NUM> caused by the automatic travel control unit 60a is discussed. As shown in <FIG>, the automatic travel control unit 60a determines, on the basis of the machine body position W1 and the planned travel route L, whether or not the machine body position W1 detected by the position detecting device <NUM> during automatic travel is located at a position short of a start point La of a straight section L1 or at the start point La (S1). If the automatic travel control unit 60a determines that the machine body position W1 is located at a position short of a start point La of a straight section L1 or at the start point La (Yes in S <NUM>), the automatic travel control unit 60a determines whether or not the deviation in direction θg is equal to or greater than a threshold (S2). If the automatic travel control unit 60a determines that the deviation in direction θg is equal to or greater than a threshold (Yes in S2), the automatic travel control unit 60a sets the angle of steering so that the deviation in direction θg approaches zero (S3), and switches the transmission <NUM> to rearward travel to cause the machine body <NUM> to travel a predetermined distance rearward (S4, short rearward travel). After causing the machine body <NUM> to travel a predetermined distance rearward (S4), the automatic travel control unit 60a sets the angle of steering so that the deviation in direction θg further approaches zero (S5), and switches the transmission <NUM> to forward travel and causes the machine body <NUM> to travel a predetermined distance forward to move to the position short of the start point La of the straight section L1 or to the start point La (S6, short forward travel).

After the automatic travel control unit 60a has caused the machine body <NUM> to travel a predetermined distance rearward (S4), the flow proceeds to S2, and the automatic travel control unit 60a determines whether or not the deviation in direction θg is equal to or greater than the threshold (S2). Thus, the automatic travel control unit 60a repeats the short rearward travel and the short forward travel until the deviation in direction θg from the straight section L1 becomes less than the threshold.

If the automatic travel control unit 60a determines that the deviation in direction θg is less than the threshold (No in S2), the automatic travel control unit 60a ends the three-point-turn movement.

Note that, although the working machine <NUM> performs the three-point-turn movement on the basis of the angle (deviation in direction) θg of the machine body heading direction F1 to the planned travel route L in the above-described embodiment, the method for the three-point-turn movement is not limited to that described above. The automatic travel control unit 60a may control the three-point-turn movement as follows: in the case where the deviation in position between the machine body position W1 and the planned travel route L at a position short of the start point La or at the start point La is equal to or greater than a threshold, the automatic travel control unit 60a sets the angle of steering so that the deviation in position is zero (the machine body heading direction F1 matches the direction of the planned travel route L). The automatic travel control unit 60a may control the three-point-turn movement by setting the angle of steering for automatic travel on the basis of an angle of steering determined on the basis of the deviation in position and an angle of steering determined on the basis of the deviation in direction. The three-point-turn movement (recovery movement) in automatic travel in the above-described embodiment is an example, and does not imply any limitation.

As illustrated in <FIG>, the control device <NUM> includes a threshold setting unit 60b to set a threshold for the three-point-turn movement according to work. The work is, for example, work that can be done by the working device <NUM> linked to the raising/lowering device <NUM>. The threshold setting unit 60b is composed of electrical/electronic circuit(s), program(s) stored in a CPU and/or the like, and/or the like. Note that, although the threshold setting unit 60b is composed of electrical/electronic circuit(s) of the control device <NUM>, program(s) stored in a CPU and/or the like of the control device <NUM>, and/or the like in the present embodiment, the threshold setting unit 60b may be composed of electrical/electronic circuit(s) of some other apparatus other than the control device <NUM> such as the display device <NUM>, program(s) stored in a CPU and/or the like of the apparatus, and/or the like.

The working machine <NUM> includes selection member(s) <NUM> via which work can be selected. The threshold setting unit 60b sets a threshold according to the work selected via any of the selection member(s) <NUM>. Work that can be selected via the selection member(s) <NUM> is, for example, work that can be done by the working device <NUM> linked to the raising/lowering device <NUM>. Note that, although work that can be selected via the selection member(s) <NUM> is, for example, work that can be done by the working device <NUM> linked to the raising/lowering device <NUM> in the present embodiment, the work that can be selected via the selection member(s) <NUM> is not limited to the work that can be done by the working device <NUM> linked to the raising/lowering device <NUM>. As illustrated in <FIG>, in the present embodiment, the selection member(s) <NUM> is/are piece(s) of first graphics <NUM> displayed on the display unit <NUM>, and an operator can select work by performing the operation to select any of the selection member(s) <NUM>. The selection member(s) <NUM> is/are displayed on a selection screen M1 of the display unit <NUM>. The display unit <NUM> displays the selection screen M1 upon a predetermined operation on the display device <NUM>, and the selection screen M1 displays a plurality of selection members <NUM> corresponding to types of work. In the present embodiment, the selection members <NUM> indicate, as the types of work, work content (work categories) corresponding to working devices <NUM>. The selection screen M1 also displays a first confirmation button <NUM> via which the selection of any of the selection members <NUM> is confirmed.

Note that the selection members <NUM> need only make it possible to select work. The selection of work may be performed by selecting a working device instead of selecting work content (work category), and the method of the selection is not limited to the method as described above.

In the case where the display device <NUM> is not an operable touchscreen or the like, the selection members <NUM> may be operation actuators (operation switches) which are provided on the display device <NUM> or the like and which are operable. The selection members <NUM> may be selection members <NUM> displayed on a PC or a mobile terminal such as a smartphone connected in a wireless or wired manner to the working machine <NUM>. The above-described configuration does not imply any limitation.

At least two types of work can be selected via the selection members <NUM>. The selection members <NUM> are associated with the types of work, and the selection members <NUM> input operation information into the control device <NUM>. The types of work that can be selected via the selection members <NUM> include first work and second work for which less work accuracy (accuracy of work) is required than for the first work. In the present embodiment, working devices <NUM> that can be selected via the selection members <NUM> include third work for which less work accuracy is required than for the first work but more work accuracy is required than for the second work, in addition to the first work and the second work. The first work to the third work correspond to one or more types of work content or one or more working devices.

For example, the first work includes seeding work done by a seeder, and the second work includes fertilization work done by a fertilizer spreader and/or stubble cultivation done by a stubble cultivator. Furthermore, the third work is, for example, cultivating work, which is work other than at least the seeding work, the fertilization work, and the stubble cultivation, and work for which less work accuracy is required than for the seeding work but more work accuracy is required than for the fertilization work and the stubble cultivation. In such a case, the selection members <NUM> (pieces of first graphics <NUM>) displayed on the selection screen M1 of the display unit <NUM> include a first selection item 40a, a second selection item 40b, a third selection item 40c, and a fourth selection item 40d. The first selection item 40a corresponds to the seeding work which is the first work, and displays "seeding" which is the name corresponding to the seeding work. The second selection item 40b corresponds to the fertilization work which is the second work, and displays "fertilization" which is the name corresponding to the fertilization work. The third selection item 40c corresponds to stubble cultivation which is the second work, and displays the "stubble cultivation" which is the name corresponding to the stubble cultivation. The fourth selection item 40d corresponds to the cultivating work which is the third work, and displays "cultivation" which is the name corresponding to the cultivating work.

Note that the types of work that can be selected via the selection members <NUM> need only include at least first work and second work for which less work accuracy is required than for the first work, and the types of work that can be selected via the selection members <NUM> are not limited to the above-described types, and the categories thereof are not limited to the above-described categories. For example, the first work may include spreading work done by a spreader, and the second work may include work to be done against the ground done by a ground implement. In such a case, for example, the first work is seeding work done by a seeder, agricultural chemical spreading done by an agricultural chemical spreader, or the like which is a type of spreading work, and the second work is stubble cultivation and cultivating work and/or the like.

The threshold setting unit 60b acquires a threshold from the storage device <NUM> on the basis of the operation of any of the selection members <NUM>, and sets the acquired threshold as a threshold for the three-point-turn movement. There are at least two thresholds having different values, which are set so as to correspond to the respective types of work. Specifically, the thresholds include a first threshold (e.g., <NUM> degree) corresponding to the first work and a second threshold (for example, <NUM> degrees) which corresponds to the second work and which is greater than the first threshold (the second threshold > the first threshold). The storage device <NUM> stores operation on each selection member <NUM>, i.e., each type of work, and a threshold such that the work and the threshold are associated with each other, and stores the first threshold and the second threshold.

In the present embodiment, the thresholds include, in addition to the first threshold and the second threshold, a third threshold (e.g., <NUM> degrees) which differs from the first threshold and the second threshold and which corresponds to the third work. The third threshold is greater than the first threshold and is less than the second threshold (first threshold < third threshold < second threshold). The storage device <NUM> stores the first threshold, the second threshold, and the third threshold such that the first work is associated with the first threshold, the second work is associated with the second threshold, and the third work is associated with the third threshold.

Upon operation of the first confirmation button <NUM> with the first selection item 40a selected on the selection screen M1, information about operation of (operation information of) the first selection item 40a is inputted into the threshold setting unit 60b from the display device <NUM>, and the threshold setting unit 60b acquires the first threshold from the storage device <NUM> and sets the first threshold as a threshold for the three-point-turn movement. Upon operation of the first confirmation button <NUM> with the second selection item 40b or the third selection item 40c selected on the selection screen M1, operation information of the second selection item 40b or the third selection item 40c is inputted into the threshold setting unit 60b from the display device <NUM>, and the threshold setting unit 60b acquires the second threshold from the storage device <NUM> and sets the second threshold as a threshold for the three-point-turn movement. Upon operation of the first confirmation button <NUM> with the third selection item 40c selected on the selection screen M1, operation information of the third selection item 40c is inputted into the threshold setting unit 60b from the display device <NUM>, and the threshold setting unit 60b acquires the third threshold from the storage device <NUM> and sets the third threshold as a threshold for the three-point-turn movement.

Note that the thresholds need only include values corresponding to types of work that can be selected via the selection members <NUM>, and the values are not limited to the first threshold and the second threshold. The thresholds may include the foregoing third threshold. In the case where working devices <NUM> that can be selected via the selection members <NUM> include forth work in addition to the first work to the third work, the thresholds include a fourth threshold in addition to the first to third thresholds.

Furthermore, the working machine <NUM> may include an input device <NUM> capable of receiving input of work accuracy, and the threshold setting unit 60b may correct a threshold according to the work accuracy inputted into the input device <NUM>. The input device <NUM> is a device which is connected to the threshold setting unit 60b (control device <NUM>) communicably in a wired or wireless manner and which is capable of receiving input of work accuracy. In the present embodiment, the input device <NUM> is the display device <NUM>, and work accuracy can be inputted by selecting any of pieces of second graphics <NUM> displayed on the display unit <NUM>. Note that the input device <NUM> is not limited to the display device <NUM>, and the input device <NUM> may be an operation actuator which is provided on the working machine <NUM> and which is operable or a PC or a mobile terminal such as a smartphone communicably connected to the working machine <NUM> in a wireless or wired manner. The foregoing configuration does not imply any limitation.

As illustrated in <FIG>, the input device <NUM> (display device <NUM>) displays, on the display unit <NUM>, the pieces of second graphics <NUM> which correspond to work accuracies and which are selectable and operable. Upon operation of any of the pieces of second graphics <NUM>, a corresponding work accuracy is inputted into the threshold setting unit 60b. The pieces of second graphics <NUM> are displayed on an input screen M2 of the display unit <NUM>. The display unit <NUM> displays the input screen M2 upon operation to select one of the selection members <NUM> on the selection screen M1, and the plurality of pieces of second graphics <NUM> corresponding to work accuracies are displayed on the input screen M2. Furthermore, the input screen M2 displays a second confirmation button <NUM> via which the input of a work accuracy is confirmed.

In the present embodiment, the pieces of second graphics <NUM> indicate work accuracies corresponding to the first to third thresholds. The display device <NUM> includes, for example, a first input item 45a with "high accuracy" corresponding to the first threshold, a second input item 45b with "high efficiency" corresponding to the second threshold, and a third input item 45c with "normal" corresponding to the third threshold. The input screen M2 displays the pieces of second graphics <NUM> such that a piece of second graphics <NUM> corresponding to the threshold (one of the first to third thresholds) set by the threshold setting unit 60b is preselected. Upon operation of the second confirmation button <NUM> by an operator, the selection of the selected piece of second graphics <NUM> is confirmed.

For example, in the case where the first selection item 40a is selected on the selection screen M1 and the threshold set by the threshold setting unit 60b is the first threshold, the input screen M2 displays the first input item 45a corresponding to the first threshold in a preselected manner. In the case where the second selection item 40b or the third selection item 40c is selected on the selection screen M1 and the threshold set by the threshold setting unit 60b is the second threshold, the input screen M2 displays the second input item 45b corresponding to the second threshold in a preselected manner. In the case where the fourth selection item 40d is selected on the selection screen M1 and the threshold set by the threshold setting unit 60b is the third threshold, the input screen M2 displays the third input item 45c corresponding to the third threshold in a preselected manner. The input device <NUM> inputs the work accuracy into the threshold setting unit 60b on the basis of the operation to select the selected piece of second graphics <NUM>.

The storage device <NUM> stores work accuracies inputted from the input device <NUM> and thresholds such that the work accuracies are associated with the thresholds. The threshold setting unit 60b acquires a threshold from the storage device <NUM> on the basis of the work accuracy inputted from the input device <NUM>, and corrects the acquired threshold as a threshold for the three-point-turn movement.

Thus, upon operation of the second confirmation button <NUM> with the first input item 45a selected on the input screen M2, a work accuracy corresponding to the first input item 45a is inputted from the input device <NUM> into the threshold setting unit 60b, and the threshold setting unit 60b acquires the first threshold from the storage device <NUM> and corrects the first threshold as a threshold for the three-point-turn movement. Upon operation of the second confirmation button <NUM> with the second input item 45b or the third input item 45c selected on the input screen M2, a work accuracy corresponding to the second input item 45b or the third input item 45c is inputted from the input device <NUM> into the threshold setting unit 60b, and the threshold setting unit 60b acquires the second threshold from the storage device <NUM> and corrects the second threshold as a threshold for the three-point-turn movement. Upon operation of the second confirmation button <NUM> with the fourth input item selected on the input screen M2, a work accuracy corresponding to the fourth input item is inputted from the input device <NUM> into the threshold setting unit 60b, and the threshold setting unit 60b acquires the third threshold from the storage device <NUM> and corrects the third threshold as a threshold for the three-point-turn movement.

Note that the threshold setting unit 60b need only correct a threshold on the basis of the work accuracy inputted from the input device <NUM>, that the thresholds to be corrected are not limited to the first to third thresholds and may be different values, and that a method of correction is not limited to that described above. For example, the threshold setting unit 60b may correct a threshold by multiplying a threshold acquired from the storage device <NUM> on the basis of the operation of one of the selection members <NUM> by a predetermined correction value α based on the work accuracy inputted from the input device <NUM>. In such a case, for example, the correction value α for the second input item 45b (high accuracy) is <NUM>, the correction value α for the second input item 45b (high efficiency) is <NUM>, and the correction value α for the third input item 45c (normal) is <NUM>, and the correction values α are stored in the storage device <NUM> such that the correction values α are associated with the work accuracies inputted from the input device <NUM>. Note that the values of the correction values α are mere examples, and not limited to the values described above.

The following description discusses a flow in which the threshold setting unit 60b sets a threshold for the three-point-turn movement. As shown in <FIG>, first, upon a predetermined operation on the display device <NUM> by an operator, the display unit <NUM> displays the selection screen M1 (S11). When the display unit <NUM> has displayed the selection screen M1, the threshold setting unit 60b determines whether or not any of the selection members <NUM> has been operated and the first confirmation button <NUM> has been operated (S12). When the operator has operated any of the selection members <NUM> and has operated the first confirmation button <NUM>, the threshold setting unit 60b determines that a selection member <NUM> has been operated and the first confirmation button <NUM> has been operated (Yes in S12), and determines whether or not the operated selection member <NUM> is a selection member <NUM> corresponding to the second work (S13). Specifically, the threshold setting unit 60b determines whether or not the operated selection member <NUM> is the second selection item 40b corresponding to fertilization work or the third selection item 40c corresponding to stubble cultivation.

As shown in <FIG>, if the threshold setting unit 60b determines that the operated selection member <NUM> is a selection member <NUM> corresponding to the second work (the second selection item 40b or the third selection item 40c) (Yes in S13), the threshold setting unit 60b acquires the second threshold corresponding to the second work from the storage device <NUM> and sets the acquired second threshold as a threshold for the three-point-turn movement (S14).

As shown in <FIG>, once the threshold setting unit 60b has set the second threshold as a threshold for the three-point-turn movement (S14), the display unit <NUM> displays the input screen M2 in which the piece of second graphics <NUM> corresponding to the second threshold (second input item 45b) is displayed in a preselected manner (S15). Once the display unit <NUM> has displayed the input screen M2 (S15), the threshold setting unit 60b determines whether or not the second confirmation button <NUM> has been operated (S16). Once the operator has operated a piece of second graphics <NUM> and has operated the second confirmation button <NUM> (Yes in S16), the threshold setting unit 60b acquires, from the storage device <NUM>, a threshold corresponding to the piece of second graphics <NUM> corresponding to the work accuracy inputted into the input device (display device <NUM>), i.e., a threshold corresponding to the piece of second graphics <NUM> selected by operation, and corrects the acquired threshold as a threshold for the three-point-turn movement (S17).

As shown in <FIG>, if the threshold setting unit 60b determines that the operated selection member <NUM> is not the selection member <NUM> corresponding to the second work (not the second selection item 40b or the third selection item 40c) (No in S13), the threshold setting unit 60b determines whether or not the operated selection member <NUM> is a selection member <NUM> corresponding to the first work (S18). Specifically, the threshold setting unit 60b determines whether or not the operated selection member <NUM> is the first selection item 40a corresponding to seeding work.

As shown in <FIG>, if the threshold setting unit 60b determines that the operated selection member <NUM> is the selection member <NUM> corresponding to the first work (first selection item 40a) (Yes in S18), the threshold setting unit 60b acquires the first threshold corresponding to the first work from the storage device <NUM>, and sets the acquired first threshold as a threshold for the three-point-turn movement (S19).

As shown in <FIG>, once the threshold setting unit 60b has set the first threshold as a threshold for the three-point-turn movement (S19), the display unit <NUM> displays the input screen M2 in which the piece of second graphics <NUM> corresponding to the first threshold (first input item 45a) is displayed in a preselected manner (S20). Once the display unit <NUM> has displayed the input screen M2 (S20), the flow proceeds to S16, and the threshold setting unit 60b determines whether or not the second confirmation button <NUM> has been operated (S16).

As shown in <FIG>, if the threshold setting unit 60b determines that the operated selection member <NUM> is not the selection member <NUM> corresponding to the first work (not the first selection item 40a) (No in S18), that is, if the operated selection member <NUM> is a selection member <NUM> corresponding to the third work (fourth selection item 40d), the threshold setting unit 60b acquires the third threshold corresponding to the third work from the storage device <NUM>, and sets the acquired third threshold as a threshold for the three-point-turn movement (S21).

As shown in <FIG>, once the threshold setting unit 60b has set the third threshold as a threshold for the three-point-turn movement (S21), the display unit <NUM> displays the input screen M2 in which the piece of second graphics <NUM> corresponding to the third threshold (third input item 45c) is displayed in a preselected manner (S22). Once the display unit <NUM> has displayed the input screen M2 (S22), the flow proceeds to S16, and the threshold setting unit 60b determines whether or not the second confirmation button <NUM> has been operated (S16).

A working machine <NUM> as has been described includes a machine body <NUM> capable of traveling, a position detecting device <NUM> to detect a machine body position W1, a control device <NUM> to control the machine body <NUM> on the basis of the machine body position W1 detected by the position detecting device <NUM> and a planned travel route L, and an input device <NUM> capable of receiving input of accuracy of work, wherein the planned travel route L includes a plurality of straight sections L1 on which the machine body <NUM> travels straight, and the control device <NUM> includes a threshold setting unit 60b to set a threshold according to work, and causes the machine body <NUM> to perform a recovery movement such as to make a deviation between the machine body position W1 detected by the position detecting device <NUM> and the planned travel route L less than the threshold when the machine body <NUM> is at a start point La of any of the straight sections L1 or is about to enter the start point La of the straight section L1. The threshold setting unit 60b sets the threshold according to the work and corrects the threshold according to the accuracy of the work inputted into the input device <NUM>. With this configuration, the threshold setting unit 60b sets a threshold for each work done by the working machine <NUM>. This makes it possible for the working machine <NUM> to adjust work efficiency and work accuracy according to the content, category, or the like of work. Also, this configuration makes it possible to correct (change) the threshold as needed in addition to the working device <NUM>, and possible to improve convenience.

The working machine <NUM> further includes at least one selection member <NUM> via which the work is capable of being selected, wherein the threshold setting unit 60b sets the threshold according to the work selected via the at least one selection member <NUM>. With this configuration, an operator can select desired work by operating the selection member <NUM>, making it possible to easily adjust work efficiency and work accuracy according to work.

First work and second work for which less work accuracy is required than for the first work are capable of being selected via the at least one selection member <NUM>, the threshold setting unit 60b sets a first threshold as the threshold upon selection of the first work via the at least one selection member <NUM>; and a second threshold as the threshold upon selection of the second work via the at least one selection member <NUM>, the second threshold being greater than the first threshold. With this configuration, it is possible to perform work efficiently by setting a threshold to a large value when work does not require accuracy to thereby reduce the number of times the machine body <NUM> performs the recovery movement.

The first work includes spreading work done by a spreader, and the second work includes work against a ground done by a ground implement. With this configuration, high accuracy can be maintained by setting the threshold to a small value in the case of work in which higher priority is placed on work accuracy than on work efficiency (e.g., spreading work such as seeding work) compared to work against the ground such as stubble cultivation work.

The first work includes seeding work done by a seeder, and the second work includes fertilization work done by a fertilizer spreader and/or stubble cultivation performed by a stubble cultivator. With this configuration, high accuracy can be maintained by setting the threshold to a small value in the case of work in which higher priority is placed on work accuracy than on work efficiency (e.g., seeding work) compared to fertilization work and stubble cultivation work.

The recovery movement is a movement in which the machine body <NUM> makes a three-point turn. The three-point-turn movement of the machine body <NUM> may result in, for example, a decrease in work efficiency and large consumption of a power source such as fuel or battery of the machine body <NUM>. With the above configuration, setting the threshold on the basis of the working device <NUM> makes it possible to further improve work efficiency and achieve energy saving.

Claim 1:
A working machine (<NUM>) comprising:
a machine body (<NUM>) capable of traveling;
a position detecting device (<NUM>) configured to detect a position of the machine body (<NUM>); and
a control device (<NUM>) configured to control the machine body (<NUM>) on the basis of the position of the machine body (<NUM>) detected by the position detecting device (<NUM>) and a planned travel route (L);
wherein
the planned travel route (L) includes a straight section (L1) on which the machine body (<NUM>) travels straight, and
the control device (<NUM>) includes a threshold setting unit (60b) configured to set a threshold according to work, and cause the machine body (<NUM>) to perform a recovery movement such as to make a deviation between the position of the machine body (<NUM>) detected by the position detecting device (<NUM>) and the planned travel route (L) less than the threshold when the machine body (<NUM>) is at a start point of the straight section (L1) or is about to enter the start point of the straight section (L1), characterized in that
the working machine (<NUM>) comprises an input device (<NUM>) capable of receiving input of accuracy of the work,
wherein the threshold setting unit (60b) is configured to set the threshold according to the work and correct the threshold according to the accuracy of the work inputted into the input device (<NUM>) such that, when the work does not require accuracy, the threshold is set to a large value for the number of times the machine body (<NUM>) performs the recovery movement to be reduced and for the work to be performed efficiently.