JP2020174535A - Work vehicle - Google Patents

Abstract

To perform automated turning through simple control.SOLUTION: A work vehicle comprises running wheels, a steering device, a motor, a position acquisition device, and a control device. The running wheels are attached to a running vehicle body. The steering device adjusts a steering amount of the running wheels. The motor drives the steering device. The position acquisition device receives positioning information from positioning means and, on the basis of the received positioning information, acquires present position information of a machine body. The control device controls the motor. During turning of the machine body, the control device has a first turning operation mode, in which the motor is controlled such that the steering amount is a prescribed value regardless of the position information, and a second turning operation mode, in which the motor is controlled such that the machine body reaches a prescribed position on a turn running path on the basis of the position information.SELECTED DRAWING: Figure 5

Description

The present invention relates to a work vehicle.

Conventionally, for a work vehicle that performs work while traveling in a field, position information between a work start position and a work end position is acquired, a reference line is created from the acquired position information, and automatic traveling is performed along the created reference line. (See, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2016-21890

In the work vehicle as described above, it is conceivable to automatically turn based on the acquired position information. However, in the case of automatic turning, it is necessary to use the position information over the entire turning stroke, which complicates control.

The present invention has been made in view of the above, and an object of the present invention is to provide a work vehicle capable of performing automatic turning with simple control.

In order to solve the above-mentioned problems and achieve the object, the work vehicle (1) according to claim 1 includes traveling wheels (10, 11) attached to a traveling vehicle body (2) and the traveling wheels (10). ), The motor (95) that drives the steering device (35), and the positioning means that receive the positioning information, and based on the received positioning information, the current position information of the aircraft. The control device (100) includes a position acquisition device (150) for acquiring the above position and a control device (100) for controlling the motor (95), and the control device (100) is said to have the same regardless of the position information during the turning of the aircraft. The aircraft reaches a desired position on the turning travel path (L2) based on the first turning operation mode in which the motor (95) is controlled and executed so that the steering amount becomes a predetermined value and the position information. It is characterized by having a second turning operation mode in which the motor (95) is controlled and executed.

The work vehicle (1) according to claim 2 is the work vehicle (1) according to claim 1. The control device (100) executes the first turning operation mode at the start of turning of the airframe, and the first turning operation mode is executed. When the first turning operation mode is completed, the second turning operation mode is executed.

The work vehicle (1) according to claim 3 is the work vehicle (1) according to claim 1. The control device (100) executes the second turning operation mode at the start of turning of the airframe, and the second turning operation mode is executed. When the second turning operation mode ends, the first turning operation mode is executed, and when the first turning operation mode ends, the second turning operation mode is executed.

The work vehicle (1) according to claim 4 further includes a detection device (90) for detecting the rotation speed of the traveling wheel (11) in the work vehicle (1) according to claim 2 or 3. The detection device (90) starts detecting the rotation speed with the start of the first turning operation mode, and the control device (100) enters the second turning operation mode when the rotation speed reaches a predetermined value. It is characterized by a transition.

The work vehicle (1) according to claim 5 is a turning start operation unit (48) operated when the work vehicle (1) according to any one of claims 2 to 4 starts turning. The control device (100) is further provided with the above-mentioned turning start operation unit (48) when the distance from the current position of the aircraft based on the position information to the desired turning start position (P1) is equal to or less than a predetermined distance. The first turning operation mode or the second turning operation mode is executed based on the operation of), and the distance from the current position of the aircraft based on the position information to the desired turning start position (P1) is the predetermined distance. If it exceeds the limit, the first turning operation mode or the second turning operation mode is not executed even if the turning start operation unit (48) is operated.

The work vehicle (1) according to claim 6 is the work vehicle (1) according to any one of claims 2 to 5, wherein the control device (100) is along a straight traveling route (L1). It has an automatic straight-ahead mode for traveling the aircraft, and shifts to the automatic straight-ahead mode when the second turning operation mode toward a desired turning end position (P2) is completed.

According to the first aspect of the present invention, since the first turning operation mode, which is not the operation mode based on the position information, is executed while the aircraft is turning, it is not necessary to use the position information for all the controls related to the automatic turning. That is, the control using the position information during the automatic turning is partially improved, and the automatic turning can be performed with simple control.

According to the invention of claim 2, in addition to the effect of the invention of claim 1, the first turning operation mode is executed at the start of turning of the airframe, and the second turning operation mode is executed at the end of turning. Therefore, automatic turning can be performed with simpler control.

According to the invention of claim 3, in addition to the effect of the invention of claim 1, the first is when the aircraft is going straight during turning after the end of the second turning operation mode executed at the start of turning of the aircraft. Since the turning operation mode is executed, it is possible to reduce the traveling error due to slipping of the traveling wheels in the first turning operation mode, and it is possible to accurately perform automatic turning as a whole of the turning stroke.

According to the invention of claim 4, in addition to the effect of the invention of claim 2 or 3, the detection (counting) of the rotation speed of the traveling wheel is started with the start of the first turning operation mode, and the vehicle travels. When the number of rotations of the wheels reaches a predetermined value, the mode shifts to the second turning operation mode. Therefore, similarly to the above, some control using position information during automatic turning is sufficient, and automatic turning can be performed with simple control. ..

According to the invention of claim 5, in addition to the effect of the invention of any one of claims 2 to 4, turning starts when the distance from the current position of the airframe to the desired turning start position is short. When the operation unit is operated, the first turning operation mode or the second turning operation mode is executed. On the other hand, when the distance from the current position of the aircraft to the desired turning start position is long, the first turning operation mode or the second turning operation mode is not executed even if the turning start operation unit is operated. In this way, for example, even if the turning start operation unit is operated at a position other than the turning start position such as near the center of the field, that is, even if it is erroneously operated, the first turning operation mode or the second turning operation mode is not executed. It is possible to prevent erroneous operation.

According to the invention of claim 6, the second turning operation mode toward the desired turning end position (when the second turning operation mode is performed twice or more while the aircraft is turning, the final second turning operation mode ) Is completed, the mode shifts to the automatic straight-ahead mode and the automatic straight-ahead mode is started. Therefore, the work can be continuously performed and the workability can be improved.

FIG. 1 is a side view showing an example of a work vehicle. FIG. 2 is a plan view showing an example of a work vehicle. FIG. 3 is a block diagram showing a control system centered on a control device. FIG. 4 is an explanatory diagram of autonomous driving in the field of the work vehicle. FIG. 5 is an explanatory diagram of automatic turning control according to the first embodiment. FIG. 6 is a flowchart showing a processing procedure of automatic turning control according to the first embodiment. FIG. 7 is a flowchart showing a control processing procedure for starting automatic turning control. FIG. 8 is a flowchart showing a control processing procedure for shifting from the first turning operation mode to the second turning operation mode. FIG. 9 is an explanatory diagram of automatic turning control according to the second embodiment. FIG. 10 is a flowchart showing a processing procedure of automatic turning control according to the second embodiment. FIG. 11 is an explanatory diagram of automatic turning control according to the third embodiment. FIG. 12 is a flowchart showing a processing procedure of automatic turning control according to the third embodiment.

Hereinafter, embodiments of the work vehicle disclosed in the present application will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments shown below.

<Overview of work vehicle>
First, an outline of the work vehicle 1 according to the embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a side view (left side) showing the work vehicle 1. FIG. 2 is a plan view showing the work vehicle 1.

In the following description, the front-rear direction is the traveling direction when the work vehicle 1 travels straight, and the front side of the traveling direction is defined as "front" and the rear side is defined as "rear". The traveling direction of the work vehicle 1 is a direction from the driver's seat 41 toward the steering wheel 35 when traveling straight (see FIGS. 1 and 2).

The left-right direction is a direction that is horizontally orthogonal to the front-back direction, and defines the left-right direction toward the "front" side. That is, when the operator (also referred to as an operator) is seated in the driver's seat 41 and faces forward, the left hand side is "left" and the right hand side is "right".

The vertical direction is the vertical direction. The front-back direction, the left-right direction, and the up-down direction are orthogonal to each other. Each direction is defined for convenience of explanation, and the present invention is not limited to these directions.

Further, in the following description, the work vehicle 1 may be referred to as an "aircraft". In the embodiment, the work vehicle will be described as a riding-type seedling transplanter 1 having a seedling planting unit 4 as a work device and receiving seedlings in a field. As shown in FIGS. 1 and 2, the seedling transplanter 1 is provided with a seedling planting unit 4 (working device) capable of raising and lowering seedlings in a field via an elevating link mechanism 3 on the rear side of the traveling vehicle body 2. ..

The main body portion of the fertilizer application device 5 is arranged on the upper rear side of the traveling vehicle body 2. If the work vehicle is not the seedling transplanter 1, a seeding device or the like for supplying seeds may be provided as the work device.

The traveling vehicle body 2 is a four-wheel drive vehicle including left and right front wheels 10 and rear wheels 11, which are traveling wheels and driving wheels. On the front side of the main frame 15 constituting the vehicle body skeleton of the traveling vehicle body 2, a mission case 13 for transmitting a driving force to a seedling planting portion 4 and the like and a driving force supplied from the engine 30, that is, the engine 30 are generated. A hydraulic continuously variable transmission 14 (main speed change mechanism) that outputs rotation to the mission case 13 is provided.

The continuously variable transmission 14 is a so-called HST (Hydro Static Transmission) hydrostatic continuously variable transmission. Hereinafter, the case where the continuously variable transmission is HST14 will be described.

The transmission case 13 is provided with an auxiliary transmission mechanism 16 that switches the traveling mode of the traveling vehicle body 2 when traveling on the road in the high-speed mode or when planting seedlings in the low-speed mode. Front wheel final cases 10a are provided on the left and right sides of the mission case 13, and the front wheels 10 are provided on the left and right front axles 10b that project outward from the front wheel support portions that can change the steering direction of the left and right front wheel final cases 10a. Is attached.

Further, on the rear side of the main frame 15, rear wheel gear cases 11a are attached to both left and right sides of the rear frame 22 (see FIG. 2) provided in the lateral direction of the fuselage, and each protrudes outward from the rear wheel gear case 11a. The rear wheels 11 (running wheels) are attached to the left and right rear axles 11b.

Further, left and right link support frames 23 for supporting the elevating link mechanism 3 are projected upward from the upper portion of the rear frame 22. A pair of left and right lower link arms 24 are provided on the lower side of the left and right link support frames 23 and between the left and right. An elevating cylinder 25 (elevating device) operated by hydraulic pressure is provided between the left and right of the left and right lower link arms 24.

An upper link arm 26 is provided above the elevating cylinder 25, and an elevating link mechanism 3 which is a parallel link mechanism is configured. The left and right lower link arms 24, the elevating cylinder 25, and the other end of the upper link arm 26, one end of which is connected to the traveling vehicle body 2, are attached to the front portion of the seedling planting portion 4. ..

Further, the engine 30 is mounted on the main frame 15. The rotational power of the engine 30 is transmitted to the mission case 13 via the belt transmission device 21 and the HST 14. The rotational power transmitted to the transmission case 13 is divided into running power and external extraction power after being changed by the auxiliary transmission mechanism 16 in the mission case 13.

Further, the rotational power of the engine 30 is transmitted to a hydraulic pump (not shown). The hydraulic pressure generated by the hydraulic pump is supplied to the HST 14, the power steering mechanism 88 of the handle 35 (see FIG. 3), the elevating cylinder 25, and the like.

The external extraction power extracted from the rotational power transmitted to the mission case 13 is transmitted to the planting clutch case 27 provided at the rear of the traveling vehicle body 2, and the seedlings are planted from the planting clutch case 27 by the planting transmission shaft 67. It is transmitted to the part 4.

On the other hand, left and right drive shafts 42 are provided at the rear of the mission case 13. The rotational power from the engine 30 is transmitted to the left and right rear wheel gear cases 11a via the transmission case 13 and the drive shaft 42.

A side clutch 44 (see FIG. 3) for turning on / off the power transmission to the left and right drive shafts 42 is arranged on the side superior to the left and right drive shafts 42 in the transmission direction. As shown in FIG. 1, a side clutch pedal 43a for turning on / off the left and right side clutches 44 is provided on the lower front side of the driver's seat 41 and on the left and right sides.

Of the left and right side clutch pedals 43a, when the side clutch pedal 43a on the inside of the turn is depressed to disengage the side clutch 44 and then the handle 35 is operated to turn, the drive rotation of the rear wheel 11 on the inside of the turn is completely completed. It can be blocked.

As a result, the turning radius can be made smaller than that of the turning running by operating the handle 35 alone, and the work start position of the work strip suitable for the field condition can be appropriately selected, and the work accuracy is improved.

In this way, the transmission to the rear wheel 11 on the inside of the turn can be stopped during the turn, the turning radius can be reduced, and the work position before the turn and the work position after the turn can be prevented from being separated from each other. It eliminates the need to readjust the work start position, improving work efficiency and work accuracy.

In the embodiment, in the automatic turning control described later, when the traveling vehicle body 2 is turned by operating the steering wheel 35, the side clutch 44 located inside the turning is disengaged and the transmission to the rear wheels 11 inside the turning is performed. Is configured to stop.

A bonnet 39 having a control panel 38 for operating each part is provided on the upper part of the front side of the traveling vehicle body 2. The control panel 38 is provided with an automatic turning switch 48 for switching whether or not to perform automatic turning control, which will be described later, a monitor 86 (see FIG. 3), and the like.

Further, the bonnet 39 is provided with a handle 35 for steering the machine body, a shift operation lever 36 for operating the HST 14 and the seedling planting portion 4, an auxiliary shift operation lever 37 for operating the auxiliary transmission mechanism 16.

Further, a front cover 40 that can be opened and closed is provided on the front side of the bonnet 39. Inside the front cover 40, an interlocking mechanism for rotating the lower side of the left and right front wheels 10 and the left and right front wheel final cases 10a is provided for steering the fuel tank, the battery, and the steering wheel 35.

An engine cover 30a that covers the upper portion and the side portion of the engine 30 is provided on the rear side of the bonnet 39 and above the engine 30, and the driver's seat 41 on which the operator is seated is provided on the upper portion of the engine cover 30a. Is provided.

A fertilizer application device 5 is provided on the rear side of the driver's seat 41 and on the rear end side of the main frame 15. The driving force of the fertilizer application device 5 is transmitted by a fertilizer application transmission mechanism provided so as to face the fertilizer application device 5 from the left and right sides of the left and right rear wheel gear cases 11a.

By the way, substantially horizontal floor steps 33 are formed on both the left and right sides of the lower portion of the engine cover 30a and the bonnet 39. As shown in FIG. 2, the floor step 33 has a partial grid pattern. For example, even if the mud attached to the shoes of the operator walking on the floor step 33 falls, the fallen mud or the like falls on the field.

Further, as shown in FIG. 2, a rear step 330 is connected behind the floor step 33. It is preferable that the surface of the rear step 330 is subjected to anti-slip processing in which, for example, a plurality of protrusion patterns are formed so that the foot does not slip easily during work.

Further, on the front side of the traveling vehicle body 2 and on both the left and right sides, spare seedling frames 50 for arranging a plurality of spare seedling mounting stands 52 at intervals in the vertical direction are provided on the seedling frame columns 51, respectively. Work materials such as seedlings and fertilizer bags to be replenished in the attachment 4 can be placed.

Further, a seedling tank 53 for loading seedlings to be planted in the field is mounted at the rear end of the elevating link mechanism 3 together with a sliding mechanism that slides in the left-right direction. In the seedling tank 53, seedling partition fences 54 long in the vertical direction are arranged at predetermined intervals in the horizontal direction. Below the seedling tank 53, a seedling planting device 55 that scrapes off the loaded seedlings and plants them in the field is arranged.

The seedling planting device 55 plants the same number of planting work rows as the number of planting work rows separated by the seedling partition fence 54, that is, eight rows at the same time, and the planting transmission case 56 is spaced below the seedling tank 53 4 The planting rotary 57 is mounted on each of the planting rotary cases 57, which are arranged and rotated on both the left and right sides of the planting transmission case 56 to take seedlings by a planting rod 58 and plant them in a field.

In the fertilizer application device 5, the fertilizer hopper 70 for storing fertilizer is partitioned into the same number as the number of working rows of the seedling planting portion 4 (8 rows in the example shown in FIG. 2). Since the fertilizer hopper 70 for eight rows is long in the left-right direction, the convenience of putting in and taking off fertilizer is reduced. Therefore, the fertilizer hopper 70 is divided into four rows and arranged side by side, respectively. May be good.

At the lower part of the fertilizer application hopper 70, a feeding device 71 for supplying a set amount of fertilizer is provided for each row. Below the feeding device 71, ventilation ducts 72 through which the transport air for moving fertilizer passes are provided in the left-right direction of the machine body. Below the feeding device 71, a fertilizer application hose 73 for guiding fertilizer is provided in the vicinity of the seedling planting position of the seedling planting portion 4. Further, at one end of the body of the ventilation duct 72, a blower 74 that is operated by an electric motor 76 for a blower to generate a transport air is provided.

As shown in FIGS. 1 and 2, below the seedling planting portion 4, a center float 62C that slides in contact with the field scene and two side floats 62L and 62R on each side rotate around the axis. It is provided freely. The center float 62C and the left and right side floats 62L and 62R may be collectively referred to as the float 62.

Further, below the seedling planting portion 4, a ground leveling rotor 63 for leveling the unevenness of the field scene is provided on the front side of the machine body with respect to the float 62. For example, the driving force is transmitted from the rear wheel gear cases 11a on the left and right sides to the ground leveling rotor 63 via the rotor transmission shaft 63a.

Further, as shown in FIG. 1, on the left and right sides of the seedling planting portion 4, either the left or right side is in contact with the field scene, and a groove is formed as a guideline for running in the next work line (next step). Draw markers 65 are provided respectively. When one of the left and right sides of the line drawing marker 65 touches the ground, the other side is separated upward, when the seedling planting portion 4 is raised during turning, both the left and right sides are separated upward, and when the seedling planting portion 4 is lowered after turning, One side on the left and right is separated upward and the other side is grounded.

Further, as shown in FIGS. 1 and 2, a center mascot 66 which is long in the vertical direction is provided at the center left and right of the traveling vehicle body 2 and in front of the bonnet 39. By aligning the center mascot 66 with the groove formed in the field by the left and right line drawing markers 65, it is possible to run according to the work position of the immediately preceding work line, improving work accuracy and preventing non-work. be able to.

Depending on the soil quality of the field, the guide line formed by the left and right line drawing markers 65 may be immediately buried, and the guideline for going straight may disappear. In such a case, it is preferable to use the left and right side markers 19 provided on the front side of the machine body with respect to the left and right line drawing markers 65. That is, by moving the left and right side markers 19 toward the outside of the machine body and locating the side markers 19 above the planted seedlings, the planting work can be performed in accordance with the planting of the seedlings in the previous work line.

Further, as shown in FIG. 1, the rice transplanter 1 includes a position acquisition device 150. The position acquisition device 150 receives positioning information from a positioning means such as GPS (Global Positioning System) or GNSS (Global Navigation Satellite System), and creates and acquires the current position information of the aircraft based on the received positioning information. The position acquisition device 150 is attached to the attachment stay 59, for example, and is arranged above the traveling vehicle body 2.

The straight-ahead control program and the turning control program created based on the position information by the position acquisition device 150 are stored in different places from each other. The straight-ahead control program is stored in, for example, the straight-ahead control ECU (Electronic Control Unit) 100a in the position acquisition device 150, and the swivel control program is stored in, for example, the swivel control ECU 100b housed in the bonnet 39. .. The straight-ahead control ECU 100a and the turning control ECU 100b are included in the control device 100 (see FIG. 3) described later.

<Control system for work vehicle>
Next, the control system C of the rice transplanter 1 will be described with reference to FIG. FIG. 3 is a block diagram showing a control system C centered on the control device 100 in the rice transplanter 1. The seedling transplanter 1 is capable of controlling each part by electronic control, and includes a control device (hereinafter, referred to as a controller) 100 for controlling each part.

The controller 100 is provided with a processing unit having a CPU (Central Processing Unit) and the like, a storage unit such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and an input / output unit, and these are connected to each other. It is possible to exchange signals with each other. A computer program or the like that controls the rice transplanter 1 is stored in the storage unit. The controller 100 exerts each function by reading a computer program or the like stored in the storage unit.

The controller 100 includes, for example, actuators such as a throttle motor 80, hydraulic control valves 81 and 82, a planted clutch operating solenoid 83, a side clutch operating solenoid 84, an HST motor 85, a drawing marker elevating motor 87, and a steering motor 95. Be connected.

The throttle motor 80 increases or decreases the rotation speed of the output shaft of the engine 30 by operating the throttle that adjusts the intake amount of the engine 30. The hydraulic control valve 81 controls the expansion / contraction operation of the elevating cylinder 25. The hydraulic control valve 82 controls the power steering mechanism 88. The planting clutch operating solenoid 83 operates the planting clutch 27a.

The side clutch operating solenoid 84 operates the side clutch 44 that switches the power transmission state to the rear wheels 11. The side clutch 44 is provided on each of the left and right rear wheels 11, and two side clutch operating solenoids 84 are provided corresponding to each side clutch 44.

The HST motor 85 changes the inclination angle of the swash plate of the HST 14 by changing the rotation angle of the trunnion of the HST 14. The steering motor 95 is a motor that drives the steering wheel 35, which is a steering device that adjusts the steering amount (steering angle) of the front wheels 10 (see FIG. 1), which are traveling wheels, when automatic turning control is performed. The steering motor 95 rotates the steering wheel 35. The draw marker lifting motor 87 raises and lowers the draw marker 65.

Further, the controller 100 is connected to a detection device such as a rotation speed sensor 90, a steering amount sensor 91, and an inclination sensor 92. Two rotation speed sensors 90 are provided corresponding to the left and right rear wheels 11 which are traveling wheels, and detect the rotation speeds of the left and right rear wheels 11, respectively. The rotation speed sensor 90 may detect the rotation speed of the left and right front wheels 10.

The steering amount sensor 91 detects the operating amount of the steering wheel 35, which is a steering device, that is, the steering amount (steering angle) of the front wheels 10. The steering amount is detected in each of the left and right directions with reference to the case where the operation amount of the steering wheel 35 is zero, that is, with reference to the time when the traveling vehicle body 2 is traveling straight. The tilt sensor 92 detects the tilt angle, which is the tilt of the traveling vehicle body 2.

Further, as operation signals, signals are input to the controller 100 from the shift operation lever 36, the auxiliary shift operation lever 37, the planting portion automatic elevating switch 47, the automatic turning switch 48, the line drawing marker automatic elevating switch 49, and the like.

The planting portion automatic raising / lowering switch 47 is a switch for switching whether or not to automatically raise / lower the seedling planting portion 4 in conjunction with the operation amount of the handle 35, that is, the steering amount of the front wheels 10. When the planting portion automatic raising / lowering switch 47 is “ON”, control for automatically raising / lowering the seedling planting portion 4 is executed in conjunction with the steering amount. On the other hand, when the planting portion automatic raising / lowering switch 47 is “OFF”, the control for automatically raising / lowering the seedling planting portion 4 in conjunction with the steering amount is not executed.

The draw marker automatic up / down switch 49 is a switch for switching whether or not to automatically raise / lower the draw marker 65 in conjunction with the operation amount of the handle 35, that is, the steering amount of the front wheels 10. When the draw marker automatic elevating switch 49 is “ON”, the control for automatically elevating the draw marker 65 in conjunction with the steering amount is executed. On the other hand, when the draw marker automatic lift switch 49 is "OFF", the control for automatically raising and lowering the draw marker 65 in conjunction with the steering amount is not executed.

The automatic turning switch 48 is a rebound switch with a lamp, and is a switch for switching whether to start or stop automatic turning. The automatic turning switch 48 is turned on while the operator turns it "ON" and the automatic turning is performed, and when the automatic turning is completed, the automatic turning switch 48 is turned "OFF" and turned off. Further, the automatic turning switch 48 is turned "OFF" by the operator during automatic turning, and turns off when the automatic turning is stopped. As a result, the operator can recognize whether or not the vehicle is automatically turning.

Further, the current position information of the aircraft is input to the controller 100 from the position acquisition device 150. The controller 100 executes an autonomous traveling mode in which the aircraft automatically travels while performing work based on the position information. Centering on the controller 100, the automatic turning switch 48, the rotation speed sensor 90, the steering amount sensor 91, the steering motor 95, the steering wheel 35, and the position acquisition device 150 constitute a control system C of the automatic turning mode described later.

<Autonomous driving mode>
Here, with reference to FIG. 4, automatic traveling (autonomous traveling) including automatic turning in the field by the seedling transplanter 1 will be described. FIG. 4 is an explanatory diagram of autonomous driving in the field of the work vehicle (rice transplanter) 1. The controller 100 (see FIG. 3) has an autonomous driving mode in which the steering motor 95 (see FIG. 3) is controlled to operate the steering wheel 35 (see FIG. 3) while feeding back the steering amount of the front wheels 10 (see FIG. 1). .. The autonomous driving mode includes an automatic straight-ahead mode and an automatic turning mode.

As shown in FIG. 4, in the autonomous traveling mode, the seedling transplanter 1 automatically performs the seedling planting work in the field F while repeating straight movement and turning along the planned traveling route. As described above, the controller 100 acquires the current position information of the seedling transplanter 1 by the position acquisition device 150 arranged above the traveling vehicle body 2.

The seedling transplanter 1 plantes seedlings while reciprocating within a predetermined work area in the field F. In this case, as for the straight running, the controller 100 executes the automatic straight running mode to automatically run along the set straight running path L1. Further, regarding the turning running, the controller 100 executes the automatic turning mode to automatically turn along the set turning running path L2.

The straight traveling path L1 is parallel to the reference line L0 which is a traveling reference. The reference line L0 is set in the field F according to the planting direction of the seedlings. The controller 100 acquires the start position and the end position of the straight running as the reference start point (point A) and the reference end point (point B), respectively, and registers the line segment connecting the points A and B as the reference line L0.

Further, the controller 100 has a first turning operation mode and a second turning operation mode as the automatic turning mode. The controller 100 executes as an automatic turning mode by combining the first turning operation mode and the second turning operation mode. The controller 100 executes the automatic turning mode when the automatic turning switch 48 is turned "ON" by the operator.

In the first turning operation mode, the controller 100 controls the steering motor 95 so that the steering amount of the handle 35 becomes a predetermined value while the rice transplanter 1 is turning. In this case, the controller 100 executes the process regardless of the position information acquired by the position acquisition device 150.

In the second turning operation mode, the controller 100 causes the seedling transplanter 1 to move to any desired position on the turning traveling path L2 based on the position information acquired by the position acquisition device 150 while the seedling transplanter 1 is turning. The steering motor 95 is controlled so as to reach it.

As described above, since the controller 100 has the first turning operation mode and the second turning operation mode and executes the first turning operation mode which is not the operation mode based on the position information during the turning of the aircraft, the automatic turning is performed. It is not necessary to use position information for all such controls. Therefore, the control using the position information during the automatic turning is partially improved, and the automatic turning can be performed with simple control.

In the automatic turning mode, the controller 100 is based on the position information acquired by the position acquisition device 150 when the rice transplanter 1 is turning away from the turning traveling path L2 (large turn or small turn). To correct.

<Automatic turning mode according to the first embodiment>
Next, the automatic turning mode according to the first embodiment will be described with reference to FIGS. 5 to 8. FIG. 5 is an explanatory diagram of automatic turning control (automatic turning mode) according to the first embodiment. FIG. 6 is a flowchart showing a processing procedure of the automatic turning control (automatic turning mode) according to the first embodiment.

Further, FIG. 7 is a flowchart showing a control processing procedure for starting automatic turning control (automatic turning mode). FIG. 8 is a flowchart showing a control processing procedure for shifting from the first turning operation mode to the second turning operation mode.

As shown in FIG. 5, in the automatic turning mode according to the first embodiment, the seedling transplanter 1 that has progressed in the automatic straight-ahead mode has a desired turning start position (agricultural machine such as the seedling transplanter 1) set in advance. In this case, when the operator presses the automatic turning switch 48 (see FIG. 3) at a position close to P1 (which is also the work end position in Article 1), the automatic turning is started.

When the automatic turning is started, the rice transplanter 1 starts the progress in the first turning operation mode. In the first turning operation mode, the rice transplanter 1 advances along the turning traveling path L2, and ends the progress in the first turning operation mode at the end position (mode end position) P3 on the turning traveling path L2. When the seedling transplanter 1 finishes the progress in the first turning operation mode, the seedling transplanter 1 starts the progress in the second turning operation mode.

In the second turning operation mode, the seedling transplanter 1 is set to the next article at a preset desired turning end position (in the case of an agricultural machine such as the seedling transplanter 1, it is also the work start position in the next article). When the vehicle advances (straight ahead) while gradually correcting the position along the straight travel path L1 and the progress in the second turning operation mode is completed, the progress in the next article is started in the automatic straight travel mode.

As shown in FIG. 6, in the first embodiment, the controller 100 determines whether or not the automatic swivel switch 48 has been "ON" operated (step S101). When the automatic swivel switch 48 is "ON" operated (step S101: Yes), the controller 100 determines whether or not the rice transplanter 1 has reached the swivel start position P1 (step S102). When the controller 100 determines that the turning start position P1 has been reached (step S102: Yes), the controller 100 starts executing the first turning operation mode (step S103).

If the automatic swivel switch 48 is not "ON" operated in the process of step 101 (step S101: No), the controller 100 repeats the process until it is "ON" operated. Further, when the seedling transplanter 1 has not reached the turning start position P1 in the process of step 102 (step S102: No), the controller 100 repeats such a process until it reaches the turning start position P1.

Next, the controller 100 determines whether or not the rice transplanter 1 has reached the end position (mode end position) P3 of the first turning operation mode (step S104). When the controller 100 reaches the mode end position P3 (step S104: Yes), the controller 100 ends the execution of the first turning operation mode (step S105), and starts the execution of the second turning operation mode (step S106).

When the seedling transplanter 1 does not reach the mode end position P3 in the process of step 104 (step S104: No), the controller 100 repeats the process until it reaches the mode end position P3.

Next, the controller 100 determines whether or not the seedling transplanter 1 has reached the turning end position P2, which is also the ending position of the second turning operation mode (step S107). When the controller 100 reaches the turning end position P2 (step S107: Yes), the controller 100 ends the execution of the second turning operation mode (step S108), and ends the turning operation mode.

Here, in the first turning operation mode, the controller 100 sets the steering motor 95 (see FIG. 3) so that, for example, the direction of the airframe is 70 degrees on either the left or right side when the vehicle is traveling straight. Control. The controller 100 controls the steering motor 95 so that when the orientation of the aircraft is 70 degrees, it starts to return to straight running, that is, the orientation of the aircraft is 90 degrees.

When shifting from the first turning operation mode to the second turning operation mode, the controller 100 sets the steering motor 95 so that the direction of the aircraft falls within the range of 0 to 20 degrees with respect to the straight traveling path L1 of the next article. Control. The controller 100 keeps the orientation of the aircraft within the range of 0 to 20 degrees at the start of the second turning operation mode, so that the position information acquired by the position acquisition device 150 (see FIG. 3) in the second turning operation mode can be obtained. Based on this, the direction of the aircraft is corrected so as to follow the straight traveling path L1, and the turning operation is completed.

When the seedling transplanter 1 does not reach the turning end position P2 in the process of step S107 (step S107: No), the controller 100 repeats the process until it reaches the turning end position P2. When the controller 100 ends the turning operation mode, the controller 100 starts executing the automatic straight-ahead mode.

Further, as shown in FIG. 7, in the process of step S101 shown in FIG. 6, the controller 100 is in progress in the automatic straight-ahead mode, and the current position of the seedling transplanter 1 is based on the position information acquired by the position acquisition device 150. It is determined whether or not the distance from to the turning start position P1 is equal to or less than a predetermined distance D (step S1011). The controller 100 calculates the mileage based on the positioning information, and determines whether or not the distance from the current position of the rice transplanter 1 to the turning start position P1 is a predetermined distance D or less. The controller 100 may calculate the mileage based on the number of rotations of the traveling wheels.

The controller 100 makes the above determination based on the mileage in the previous step, which is the planting step immediately before the planting step in the straight running this time.

It can be predicted that the turning start position P1 in the present planting process is in the vicinity of the advance by the mileage in the previous process in the present planting process. For example, it can be predicted that the position where the turning is actually started in the present planting process is within a range of about ± 5 m with respect to the mileage in the previous process.

Therefore, the controller 100 predicts the turning start position P1 based on the mileage in the previous process. Specifically, the controller 100 predicts the position where the distance traveled straight in the current planting process is the mileage in the previous process as the turning start position P1, and from the current position of the seedling transplanting machine 1 to the turning start position P1. When the distance is equal to or less than a predetermined distance D, it is determined that the distance is near the turning position, that is, at the ridge.

The turning start position P1 may be recognized by the coordinates based on the positioning information.

When the distance to the turning start position P1 is equal to or less than the predetermined distance D (step S1011: Yes), the controller 100 executes the first turning operation mode when the automatic turning switch 48 is "ON" operated (step S1011: Yes). S1012).

When the distance to the turning start position P1 exceeds the predetermined distance D in the process of step S1011 (step S1011: No), the controller 100 sets the first turning operation mode even if the automatic turning switch 48 is operated "ON". The automatic straight-ahead mode is continued without executing (step S1013).

Further, the end position P3 of the first turning operation mode is set based on the rotation speed of the rear wheel 11 (see FIG. 1) detected (counted) by the rotation speed sensor 90 (see FIG. 3). As shown in FIG. 8, when the controller 100 starts executing the first turning operation mode in the process of step S103 shown in FIG. 6, the controller 100 starts counting the rotation speed of the rear wheels 11 (step S1031). ), It is determined whether or not the rotation speed of the rear wheel 11 has reached a predetermined value (count value) (step S1032).

When the rotation speed of the rear wheels 11 reaches a predetermined count value (step S1032: Yes), the controller 100 determines that the end position P3 has been reached, ends the execution of the first turning operation mode, and makes the second turning. The operation mode is executed (step S1033). If the rotation speed of the rear wheel 11 is not a predetermined count value in the process of step S1032 (step S1032: No), the controller 100 repeats the process until the count value is reached.

According to the first embodiment described above, the first turning operation mode is executed at the start of turning of the rice transplanter 1, and the second turning operation mode is executed at the end of turning, so that automatic turning can be performed with simpler control. It can be carried out.

Further, the number of rotations of the rear wheels 11 is counted with the start of the first turning operation mode, and when the number of rotations of the rear wheels 11 reaches a predetermined count value, the mode shifts to the second turning operation mode. Therefore, during automatic turning. Control using position information is partially improved, and automatic turning can be performed with simple control.

Further, when the distance from the current position of the rice transplanter 1 to the turning start position P1 is short, the first turning operation mode is executed when the automatic turning switch 48 is operated to "ON". On the other hand, when the distance from the current position of the seedling transplanter 1 to the turning start position P1 is long, the first turning operation mode is not executed even if the automatic turning switch 48 is operated. In this way, even if the automatic turning switch 48 is operated (that is, erroneous operation) at a position other than the turning start position P1 such as near the center of the field, the erroneous operation can be prevented by not executing the first turning operation mode. ..

Further, when the second turning operation mode toward the turning end position P2 ends, the mode shifts to the automatic straight-ahead mode and the automatic straight-ahead starts, so that the work can be continuously performed and the workability can be improved. ..

In the first embodiment, the first turning operation mode is executed and then the second turning operation mode is executed. As a modification, for example, the second turning operation mode is executed and then the first turning operation mode is executed. It may be executed to reach the turning end position P2.

<Automatic turning mode according to the second embodiment>
Next, the automatic turning mode according to the second embodiment will be described with reference to FIGS. 9 and 10. FIG. 9 is an explanatory diagram of the automatic turning control (automatic turning mode) according to the second embodiment. FIG. 10 is a flowchart showing a processing procedure of the automatic turning control (automatic turning mode) according to the second embodiment.

As shown in FIG. 9, in the automatic turning mode according to the second embodiment, the seedling transplanter 1 that has proceeded in the automatic straight-ahead mode, as in the first embodiment described above, has a desired turning start position P1 set in advance. When the automatic turning switch 48 (see FIG. 3) is pressed by the operator at a position close to, the automatic turning is started.

When the automatic turning is started, the rice transplanter 1 starts the progress in the second turning operation mode (first time) and proceeds along the turning traveling path L2. The seedling transplanter 1 ends the progress in the first second turning operation mode at the ending position (mode ending position) P4 on the turning traveling path L2.

When the seedling transplanter 1 finishes the progress in the first second turning operation mode, the seedling transplanter 1 starts the progress in the first turning operation mode. The seedling transplanter 1 ends the progress in the first turning operation mode at the mode ending position P5 on the turning traveling path L2. When the seedling transplanter 1 finishes the progress in the first turning operation mode, the seedling transplanter 1 starts the progress in the second turning operation mode (second time) again.

In the second second turning operation mode, the rice transplanter 1 advances (straight ahead) while gradually correcting the position so as to follow the straight traveling path L1 of the next article at the desired turning end position P2 set in advance. Then, when the progress in the second second turning operation mode is completed, the progress in the next article is started in the automatic straight-ahead mode.

As shown in FIG. 10, in the second embodiment, the controller 100 determines whether or not the automatic swivel switch 48 has been "ON" operated (step S201). When the automatic swivel switch 48 is "ON" operated (step S201: Yes), the controller 100 determines whether or not the seedling transplanter 1 has reached the swivel start position P1 (step S202). When the controller 100 determines that the turning start position P1 has been reached (step S202: Yes), the controller 100 starts executing the second turning operation mode (first time) (step S203).

If the automatic swivel switch 48 is not "ON" operated in the process of step 201 (step S201: No), the controller 100 repeats the process until it is "ON" operated. Further, when the seedling transplanter 1 has not reached the turning start position P1 in the process of step 202 (step S202: No), the controller 100 repeats the process until it reaches the turning start position P1.

Next, the controller 100 determines whether or not the rice transplanter 1 has reached the end position (mode end position) P4 of the first second turning operation mode (step S204). When the controller 100 reaches the mode end position P4 (step S204: Yes), the controller 100 ends the execution of the first second turning operation mode (step S205), and starts the execution of the first turning operation mode (step S206). ).

When the seedling transplanter 1 does not reach the mode end position P4 in the process of step 204 (step S204: No), the controller 100 repeats the process until the mode end position P4 is reached.

Next, the controller 100 determines whether or not the seedling transplanter 1 has reached the end position (mode end position) P5 of the first turning operation mode (step S207). When the controller 100 reaches the mode end position P5 (step S207: Yes), the controller 100 ends the execution of the first turning operation mode (step S208), and starts the execution of the second turning operation mode (second time) (step). S209).

When the seedling transplanter 1 does not reach the mode end position P5 in the process of step 207 (step S207: No), the controller 100 repeats the process until the mode end position P5 is reached.

Next, the controller 100 determines whether or not the seedling transplanter 1 has reached the turning end position P2, which is also the ending position of the second second turning operation mode (step S210). When the controller 100 reaches the turning end position P2 (step S210: Yes), the controller 100 ends the execution of the second second turning operation mode (step S211), and ends the turning operation mode.

If the seedling transplanter 1 does not reach the turning end position P2 in the process of step S210 (step S210: No), the controller 100 repeats the process until it reaches the turning end position P2. When the controller 100 ends the turning operation mode, the controller 100 starts executing the automatic straight-ahead mode.

Here, when the controller 100 shifts from the first turning operation mode to the second second turning operation mode, the direction of the aircraft is within the range of, for example, 0 to 20 degrees with respect to the straight traveling path L1 of the next article. The steering motor 95 is controlled so as to enter. The controller 100 keeps the orientation of the aircraft within the range of 0 to 20 degrees at the start of the second second turning operation mode, so that the position acquisition device 150 (see FIG. 3) is used in the second second turning operation mode. The turning operation is completed by correcting the direction of the aircraft so as to follow the straight traveling path L1 based on the position information acquired by.

Further, also in the second embodiment, as in the first embodiment, the controller 100 is in the process of step S201 shown in FIG. 10 while the position acquisition device 150 (see FIG. 3) has acquired the position while the automatic straight-ahead mode is in progress. Based on the information, it is determined whether or not the current position of the seedling transplanter 1 is equal to or less than the predetermined distance D to the turning start position P1.

When the distance to the turning start position P1 is equal to or less than the predetermined distance D, the controller 100 executes the first second turning operation mode when the automatic turning switch 48 is "ON" operated.

When the distance to the turning start position P1 exceeds the predetermined distance D, the controller 100 does not execute the first turning operation mode and continues the automatic straight-ahead mode even if the automatic turning switch 48 is operated "ON".

Further, also in the second embodiment, as in the first embodiment, the end position P5 of the first turning operation mode is the rotation of the rear wheel 11 (see FIG. 1) counted by the rotation speed sensor 90 (see FIG. 3). Set based on the number. When the controller 100 starts executing the first turning operation mode in the process of step S206 shown in FIG. 10, the controller 100 starts counting the rotation speed of the rear wheel 11, and the rotation speed of the rear wheel 11 is predetermined. Determine whether or not the count value has been reached.

When the rotation speed of the rear wheels 11 reaches a predetermined count value, the controller 100 determines that the mode end position P5 has been reached, ends the execution of the first turning operation mode, and ends the execution of the second turning operation mode. To execute. If the rotation speed of the rear wheels 11 is not a predetermined count value, the controller 100 repeats the process until the count value reaches a predetermined value.

According to the second embodiment described above, the first turning operation mode is executed at the start of turning of the rice transplanter 1, and the second turning operation mode is executed at the end of turning, so that automatic turning can be performed with simpler control. It can be carried out.

Further, since the first turning operation mode is executed when the aircraft goes straight during turning after the end of the first second turning operation mode, it is possible to reduce the running error due to the slip of the rear wheels 11 in the first turning operation mode. As a whole of the turning stroke, automatic turning can be performed accurately.

In addition, the number of rotations of the rear wheels 11 is counted with the start of the first turning operation mode, and when the number of rotations of the rear wheels 11 reaches a predetermined count value, the second turning operation mode is automatically set. Control using position information during turning is partially improved, and automatic turning can be performed with simple control.

Further, when the distance from the current position of the rice transplanter 1 to the turning start position P1 is short, the first turning operation mode is executed when the automatic turning switch 48 is operated to "ON". On the other hand, when the distance from the current position of the seedling transplanter 1 to the turning start position P1 is long, the first turning operation mode is not executed even if the automatic turning switch 48 is operated. In this way, even if the automatic turning switch 48 is operated (that is, erroneous operation) at a position other than the turning start position P1 such as near the center of the field, the erroneous operation can be prevented by not executing the first turning operation mode. ..

Further, when the second second turning operation mode toward the turning end position P2 is completed, the mode shifts to the automatic straight-ahead mode and the automatic straight-ahead starts, so that the work can be continuously performed and the workability is improved. be able to.

In the second embodiment, the second turning operation mode is executed, the first turning operation mode is executed, and the second turning operation mode is executed again. As a modification, for example, the first turning operation mode is used. After the execution, the second turning operation mode may be executed, and the first turning operation mode may be executed again to reach the turning end position P2.

Further, the automatic turning mode may be set in which the first turning operation mode and the second turning operation mode are executed twice or more.

<Automatic turning mode according to the third embodiment>
Next, the automatic turning mode according to the third embodiment will be described with reference to FIGS. 11 and 12. FIG. 11 is an explanatory diagram of automatic turning control (automatic turning mode) according to the third embodiment. FIG. 12 is a flowchart showing a processing procedure of the automatic turning control (automatic turning mode) according to the third embodiment.

As shown in FIG. 11, the third embodiment is an automatic turning mode in the case of so-called back turning with a don, in which the rice transplanter 1 advances to the ridge, moves backward by a predetermined distance, and then turns.

In the automatic turning mode according to the third embodiment, in the seedling transplanter 1 that has advanced to the ridge in the automatic straight-ahead mode, the speed change operation lever (referred to as HST lever) 36 (see FIG. 3) is operated by the operator to the reverse side. Then, the work line (turning travel path L2 and the straight traveling route L1 of the next article) in the next article is acquired, and automatic turning including the reverse operation is started.

When the automatic turning is started, the rice transplanter 1 moves backward by a predetermined distance, then starts traveling in the second turning operation mode (first time), and proceeds along the turning traveling path L2. The seedling transplanter 1 ends the progress in the first second turning operation mode at the ending position (mode ending position) P6 on the turning traveling path L2.

When the seedling transplanter 1 finishes the progress in the first second turning operation mode, the seedling transplanter 1 starts the progress in the first turning operation mode. The seedling transplanter 1 ends the progress in the first turning operation mode at the mode ending position P7 on the turning traveling path L2. When the seedling transplanter 1 finishes the progress in the first turning operation mode, the seedling transplanter 1 starts the progress in the second turning operation mode (second time) again.

In the second second turning operation mode, the rice transplanter 1 advances (straight ahead) while gradually correcting the position so as to follow the straight traveling path L1 of the next article at the desired turning end position P2 set in advance. Then, when the progress in the second second turning operation mode is completed, the progress in the next article is started in the automatic straight-ahead mode.

As shown in FIG. 12, in the third embodiment, the controller 100 determines whether or not the HST lever 36 has been operated to the “backward” side (step S301). When the HST lever 36 is operated to the "backward" side (step S301: Yes), the controller 100 starts the backward movement of the rice transplanter 1 (step S302).

The controller 100 determines whether or not the rice transplanter 1 has reached the turning start position P1 (step S303). When the controller 100 determines that the turning start position P1 has been reached (step S303: Yes), the controller 100 ends the reverse movement of the rice transplanter 1 (step S304), and starts executing the second turning operation mode (first time) (step S304). Step S305).

If the HST lever 36 is not operated to the "backward" side in the process of step 301 (step S301: No), the controller 100 repeats the process until it is operated to the "backward" side. Further, when the seedling transplanter 1 has not reached the turning start position P1 in the process of step 303 (step S303: No), the controller 100 repeats such a process until it reaches the turning start position P1.

Next, the controller 100 determines whether or not the rice transplanter 1 has reached the end position (mode end position) P6 of the first second turning operation mode (step S306). When the controller 100 reaches the mode end position P6 (step S306: Yes), the controller 100 ends the execution of the first second turning operation mode (step S307), and starts the execution of the first turning operation mode (step S308). ).

When the seedling transplanter 1 does not reach the mode end position P5 in the process of step 306 (step S306: No), the controller 100 repeats the process until the mode end position P6 is reached.

Next, the controller 100 determines whether or not the rice transplanter 1 has reached the end position (mode end position) P7 of the first turning operation mode (step S309). When the controller 100 reaches the mode end position P7 (step S309: Yes), the controller 100 ends the execution of the first turning operation mode (step S310), and starts the execution of the second turning operation mode (second time) (step). S311).

When the seedling transplanter 1 does not reach the mode end position P7 in the process of step 309 (step S309: No), the controller 100 repeats the process until the mode end position P7 is reached.

Next, the controller 100 determines whether or not the seedling transplanter 1 has reached the turning end position P2, which is also the ending position of the second second turning operation mode (step S312). When the controller 100 reaches the turning end position P2 (step S312: Yes), the controller 100 ends the execution of the second second turning operation mode (step S313), and ends the turning operation mode.

If the seedling transplanter 1 does not reach the turning end position P2 in the process of step S312 (step S312: No), the controller 100 repeats the process until it reaches the turning end position P2. When the controller 100 ends the turning operation mode, the controller 100 starts executing the automatic straight-ahead mode.

Here, when the controller 100 shifts from the first turning operation mode to the second second turning operation mode, the direction of the aircraft is within the range of, for example, 0 to 20 degrees with respect to the straight traveling path L1 of the next article. The steering motor 95 is controlled so as to enter. The controller 100 keeps the orientation of the aircraft within the range of 0 to 20 degrees at the start of the second second turning operation mode, so that the position acquisition device 150 (see FIG. 3) is used in the second second turning operation mode. The turning operation is completed by correcting the direction of the aircraft so as to follow the straight traveling path L1 based on the position information acquired by.

Further, also in the third embodiment, as in the first and second embodiments, the end position P7 of the first turning operation mode is the rear wheel 11 (see FIG. 1) counted by the rotation speed sensor 90 (see FIG. 3). ) Is set based on the number of revolutions. When the controller 100 starts executing the first turning operation mode in the process of step S308 shown in FIG. 12, the controller 100 starts counting the rotation speeds of the rear wheels 11, and the rotation speeds of the rear wheels 11 are predetermined. Determine whether or not the count value has been reached.

When the rotation speed of the rear wheels 11 reaches a predetermined count value, the controller 100 determines that the mode end position P7 has been reached, ends the execution of the first turning operation mode, and ends the execution of the second turning operation mode. To execute. If the rotation speed of the rear wheels 11 is not a predetermined count value, the controller 100 repeats the process until the count value reaches a predetermined value.

The controller 100 determines whether or not the turning start position P1 has been reached based on the number of rotations of the rear wheels 11, which are traveling wheels, even in the reverse running at the initial stage of the turning operation.

According to the third embodiment described above, as in the first and second embodiments, the first turning operation mode is executed at the start of turning of the rice transplanter 1, and the second turning operation mode is executed at the end of turning. Therefore, automatic turning can be performed with simpler control.

Further, since the first turning operation mode is executed when the aircraft goes straight during turning after the end of the first second turning operation mode, it is possible to reduce the running error due to the slip of the rear wheels 11 in the first turning operation mode. As a whole of the turning stroke, automatic turning can be performed accurately.

In addition, the number of rotations of the rear wheels 11 is counted with the start of the first turning operation mode, and when the number of rotations of the rear wheels 11 reaches a predetermined count value, the second turning operation mode is automatically set. Control using position information during turning is partially improved, and automatic turning can be performed with simple control.

Further, when the second second turning operation mode toward the turning end position P2 is completed, the mode shifts to the automatic straight-ahead mode and the automatic straight-ahead starts, so that the work can be continuously performed and the workability is improved. be able to.

Also in the third embodiment, as a modification, for example, the first turning operation mode is executed, the second turning operation mode is executed, and the first turning operation mode is executed again to reach the turning end position P2. You may let me.

Further, the automatic turning mode may be set in which the first turning operation mode and the second turning operation mode are executed twice or more.

In the first to third embodiments, it is preferable that the controller 100 limits the vehicle speed by setting an upper limit value for the traveling speed of the rice transplanter 1 in the automatic turning mode. As a result, the turning operation is stable and safety can be ensured. Further, when the controller 100 determines that the turning is completed based on the position information from the position acquisition device 150, the limitation of the vehicle speed is released and the vehicle speed is set according to the position of the speed change operation lever (HST lever) 36.

Further, in the first to third embodiments, the controller 100 sets the rotation speed of the rear wheels 11 to be changeable. Further, when the assist lever is "raised" by the operator during the execution of the automatic straight-ahead mode or the automatic turning mode, the controller 100 releases each mode.

Further, in the first to third embodiments, when the controller 100 is operated by the operator to turn the Z turn "OFF" during the execution of the automatic turning mode, the controller 100 cancels the automatic turning mode. Further, the controller 100 cancels the automatic turning mode when the line drawing marker automatic raising / lowering switch 49 (see FIG. 3) is operated by the operator while the automatic turning mode is being executed.

Further, in the first to third embodiments, when the HST lever (shift operation lever) 36 (see FIG. 3) is operated by the operator during execution of the automatic turning mode, the controller 100 is operated to the "reverse" side. , Cancel the automatic turning mode. Further, the controller 100 cancels the automatic turning mode when the steering wheel 35 (see FIG. 3) is operated by the operator while the automatic turning mode is being executed.

Further, in the first to third embodiments, the controller 100 temporarily suspends the automatic turning mode when the rice transplanter 1 is stopped or the engine 30 (see FIG. 1) is stopped during the execution of the automatic turning mode. (Hold. Further, the controller 100 may control to stop the automatic turning mode when the rice transplanter 1 stops or the engine 30 stops while the automatic turning mode is being executed.

Further, in the first to third embodiments, when the ridge alarm release switch is pressed, the controller 100 releases the ridge stop when the ridge alarm is activated. Further, the controller 100 may display on the monitor 86 (see FIG. 3) whether or not automatic turning is possible. When automatic turning is not possible, the controller 100 may display an alert on the monitor 86, for example.

Further, in the third embodiment, the controller 100 does not stop the automatic turning mode even if the rice transplanter 1 stops while the seedling transplanter 1 is moving backward. As a result, even if the vehicle stops when moving backward due to an accident such as connecting seedlings, the automatic turning can be continued.

Further, in the first to third embodiments, the automatic turning mode (in the third embodiment, the operation of the automatic turning mode excluding the reverse movement) may be configured to be completed only in the first turning operation mode. Alternatively, it may be configured to be completed only in the second turning operation mode.

Further, in the first to third embodiments, the start of automatic turning may be the timing at which the "raising operation" of the raising and lowering operation of raising and lowering the seedling planting portion 4 is performed. That is, the automatic swivel switch 48 may be a switch that raises the seedling planting portion 4 by the operation of the operator, detects the rise of the seedling planting portion 4, or starts the control for raising the seedling planting portion 4. It may be a detection unit that detects.

Further, the automatic turning starts when the power transmission to the seedling planting device 55 is "cut", when the feeding device 71 of the fertilizer application device 5 is stopped, and when the power transmission to the leveling rotor 63 is "cut". It may be the timing to become.

As described above, the timing for starting the automatic turning may be the timing when the drive of the field work device such as the seedling planting portion 4 is "cut".

Further, the work vehicle 1 may be a tractor. In this case, the field work device is a rotary or the like. The above turning control can also be applied to the turning of the tractor.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments expressed and described as described above. Therefore, various modifications can be made without departing from the spirit or scope of the general concept of the invention as defined by the appended claims and their equivalents.

1 Rice transplanter (working vehicle)
2 Wheelie 10 Front wheels (wheelies)
35 steering wheel (steering device)
48 Automatic swivel switch (swivel start operation unit)
90 rpm sensor (detector)
95 Steering motor (motor)
100 controller (control device)
150 Position acquisition device L1 Straight running path L2 Turning running path P1 Turning start position P2 Turning end position

Claims (6)

The running wheels attached to the running body and
A steering device that adjusts the steering amount of the traveling wheels, and
The motor that drives the steering device and
A position acquisition device that receives positioning information from the positioning means and acquires the current position information of the aircraft based on the received positioning information.
A control device for controlling the motor is provided.
The control device turns based on the first turning operation mode in which the motor is controlled and executed so that the steering amount becomes a predetermined value regardless of the position information while the aircraft is turning, and the position information. A work vehicle characterized by having a second turning operation mode in which the motor is controlled and executed so that the machine body reaches a desired position on a traveling path. The operation according to claim 1, wherein the control device executes the first turning operation mode at the start of turning of the airframe, and executes the second turning operation mode when the first turning operation mode ends. vehicle. The control device executes the second turning operation mode at the start of turning of the airframe, executes the first turning operation mode when the second turning operation mode ends, and executes the first turning operation mode when the first turning operation mode ends. 2. The work vehicle according to claim 1, wherein the turning operation mode is executed. Further provided with a detection device for detecting the rotation speed of the traveling wheel,
The detection device starts detecting the rotation speed with the start of the first turning operation mode.
The work vehicle according to claim 2 or 3, wherein the control device shifts to the second turning operation mode when the rotation speed reaches a predetermined value. Further equipped with a turning start operation unit that is operated when starting turning of the aircraft,
When the distance from the current position of the aircraft based on the position information to the desired turning start position is equal to or less than a predetermined distance, the control device may perform the first turning operation mode or the first turning operation mode based on the operation of the turning start operation unit. When the second turning operation mode is executed and the distance from the current position of the aircraft based on the position information to the desired turning start position exceeds the predetermined distance, the first turning operation unit is operated even if the turning start operation unit is operated. The work vehicle according to any one of claims 2 to 4, wherein the turning operation mode or the second turning operation mode is not executed. The control device has an automatic straight-ahead mode in which the aircraft travels along a straight-ahead traveling path, and shifts to the automatic straight-ahead mode when the second turning operation mode toward a desired turning end position ends. The work vehicle according to any one of claims 2 to 5.

Images