Work vehicle

Abstract

The present application provides a work vehicle to automatically turn with simple control. The work vehicle of an embodiment is provided with a traveling wheel, a steering device, a motor, a position acquisition device, and a control device. The traveling wheel is mounted to a traveling vehicle body. The steering device adjusts an amount of steering of the traveling wheel. The motor drives the steering device. The position acquisition device receives position measurement information from a position measurement mechanism, and acquires position information of the vehicle body based on the received position measurement information. The control device controls the motor. In addition, the control device has a first turning operation mode and a second turning operation mode in turning of the vehicle body, the first turning operation mode being a mode executed by controlling the motor so that the amount of steering becomes a predetermined value regardless of the position information, and the second turning operation mode being a mode executed by controlling the motor so that the vehicle body reaches a desired orientation on a turning travel path based on the position information.

Description

Technical Field

[0001] This invention relates to work vehicles. Background Technology

[0002] Previously, known work vehicles that operate while driving through farmland include those that acquire position information of the start and end positions of the work, create a baseline based on the acquired position information, and automatically drive along the created baseline (for example, see Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2016-21890 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In such work vehicles, automatic slewing based on acquired position information is considered. However, in the case of automatic slewing, position information needs to be used throughout the entire slewing stroke, thus complicating control.

[0008] The present invention is proposed in view of the above circumstances, and aims to provide a work vehicle that can automatically rotate with simple control.

[0009] Solution for solving the problem

[0010] To solve the aforementioned problems and achieve the objective, the work vehicle described in Solution 1 is characterized by comprising: travel wheels 10 and 11 mounted on the travel body 2; a steering device 35 for adjusting the control amount of the travel wheels 10; a motor 95 for driving the steering device 35; a position acquisition device 150 for receiving position information from a position measuring mechanism and obtaining the current position information of the machine body based on the received position information; and a control device 100 for controlling the motor 95. The control device 100 has a first rotation operation mode and a second rotation operation mode during the rotation of the machine body. The first rotation operation mode is a mode in which the motor 95 is controlled to a predetermined value regardless of the position information. The second rotation operation mode is a mode in which the motor 95 is controlled based on the position information to reach the desired orientation on the rotation travel path L2.

[0011] The work vehicle described in Scheme 2 is based on the work vehicle described in Scheme 1, characterized in that the control device 100 executes the first rotation operation mode when the rotation of the machine body begins, and executes the second rotation operation mode when the first rotation operation mode ends.

[0012] The work vehicle described in Scheme 3, according to the work vehicle described in Scheme 1 or 2, is characterized in that it further comprises a detection device 90 for detecting the rotational speed of the aforementioned driving wheels 11. The detection device 90 begins detecting the rotational speed upon the start of the aforementioned first rotational operation mode. If the rotational speed becomes a predetermined value, the control device 100 switches to the aforementioned second rotational operation mode.

[0013] The work vehicle described in Scheme 4, according to any one of Schemes 1 to 3, is characterized in that the control device 100 has an automatic straight-line mode that causes the machine body to travel along the straight-line travel path L1, and if the second turning action mode toward the desired turning end position P2 ends, it switches to the automatic straight-line mode.

[0014] The effects of the invention are as follows.

[0015] According to the invention described in Scheme 1, the first rotation action mode is not based on position information during the rotation of the body. Therefore, it is not necessary to use position information for all aspects of the control of automatic rotation. That is, the control that uses position information in automatic rotation is only a part, and automatic rotation can be performed with simple control.

[0016] Furthermore, since the rotational speed of the driving wheel is detected (counted) at the start of the first rotational operation mode, and the rotational speed of the driving wheel reaches a predetermined value, the system switches to the second rotational operation mode. Therefore, as described above, the control using position information is only one part of the automatic rotation, and automatic rotation can be performed with simple control.

[0017] According to the invention described in Scheme 2, in addition to the effects of the invention described in Scheme 1, if the second turning action mode (the last second turning action mode in the case of performing more than two second turning action modes during the turning of the machine) ends, it will remain unchanged and transfer to the automatic straight-line mode and start automatic straight-line movement, so that the operation can continue and thus improve workability. Attached Figure Description

[0018] Figure 1 This is a side view showing an example of a work vehicle.

[0019] Figure 2 This is a top view showing an example of a work vehicle.

[0020] Figure 3 It is a block diagram representing a control system centered on a control device.

[0021] Figure 4 This is an illustration of the autonomous movement of work vehicles in farmland.

[0022] Figure 5 This is an explanatory diagram of the automatic rotation control of the first embodiment.

[0023] Figure 6 This is a flowchart illustrating the processing sequence of the automatic rotary control in the first embodiment.

[0024] Figure 7 This is a flowchart showing the control processing sequence for initiating automatic rotary control.

[0025] Figure 8 It is a flowchart showing the control processing sequence for transitioning from the first rotary motion mode to the second rotary motion mode.

[0026] Figure 9 This is an explanatory diagram of the automatic rotation control in the second embodiment.

[0027] Figure 10 This is a flowchart illustrating the processing sequence of the automatic rotation control in the second embodiment.

[0028] Figure 11 This is an explanatory diagram of the automatic rotation control in the third embodiment.

[0029] Figure 12 This is a flowchart illustrating the processing sequence of the automatic rotation control in the third embodiment.

[0030] In the picture:

[0031] 1—Seedling transplanter (operating vehicle), 2—Traveling vehicle body, 10—Front wheel (driving wheel), 35—Steering wheel (steering device), 90—Speed ​​sensor (detection device), 95—Steering motor (motor), 100—Controller (control device), 150—Position acquisition device, L1—Straight travel path, L2—Turn travel path, P2—Turn end position. Detailed Implementation

[0032] Hereinafter, embodiments of the work vehicle disclosed in this application will be described in detail with reference to the accompanying drawings. Furthermore, the present invention is not limited to the embodiments shown below.

[0033] <Overview of the work vehicle>

[0034] First, refer to Figure 1 as well as Figure 2 An overview of the work vehicle 1 in the implementation method will be described.

[0035] Figure 1 This is a side (left side) view of the work vehicle 1. Figure 2 This is a top view of the work vehicle 1.

[0036] Furthermore, in the following description, the forward and backward direction refers to the direction of travel of the work vehicle 1 when it is traveling straight, with the front side of the direction of travel defined as "front" and the rear side as "rear". The direction of travel of the work vehicle 1 is the direction from the operator's seat 41 toward the steering wheel 35 when traveling straight (refer to...). Figure 1 as well as Figure 2 ).

[0037] The left and right directions are horizontally orthogonal to the front and back directions, with the left and right sides defined as facing "forward". That is, when the operator (also known as the worker) is seated at the operating seat 41 and facing forward, the left side is "left" and the right side is "right".

[0038] The up-down direction is the direction of the plumb bob. The front-back, left-right, and up-down directions are orthogonal to each other. These directions are defined for ease of explanation, and the invention is not limited to these directions.

[0039] Furthermore, in the following description, the work vehicle 1 may be referred to as the "machine body". In the embodiment, the work vehicle will be described as a passenger-type seedling transplanter 1 equipped with a seedling planting section 4 as a working device for planting rice seedlings in farmland. Figure 1 as well as Figure 2 As shown, the seedling transplanter 1 has a seedling planting section 4 (operating device) that can be raised and lowered to plant seedlings in the field via a lifting linkage mechanism 3 on the rear side of the traveling vehicle body 2.

[0040] The main body of the fertilization device 5 is located on the upper rear side of the vehicle body 2. Furthermore, if the working vehicle is not the seedling transplanter 1, it may be equipped with a seed-supplying device or similar equipment as the working device.

[0041] The vehicle body 2 is the driving wheel, and it is a four-wheel drive vehicle with left and right front wheels 10 and rear wheels 11 as drive wheels. On the front side of the main frame 15 that constitutes the vehicle body 2, there is a gearbox 13 that transmits driving force to the seedling planting section 4, etc.; and a hydraulic continuously variable transmission device 14 (main transmission mechanism) that outputs the driving force supplied from the engine 30, that is, the rotation generated by the engine 30, to the gearbox 13.

[0042] The continuously variable transmission (CVT) 14 is a hydrostatic CVT, also known as HST (Hydro Static Transmission). The following explanation pertains to the case where the CVT is HST14.

[0043] A secondary transmission mechanism 16 is provided in the gearbox 13. This secondary transmission mechanism 16 switches the driving mode of the vehicle body 2 when driving on the road in high-speed mode or when planting seedlings in low-speed mode.

[0044] Front wheel end housings 10a are provided on the left and right sides of the gearbox 13, and front wheels 10 are mounted on the left and right front axles 10b that protrude outward from the front wheel support portion that can change the left and right direction of the front wheel end housings 10a.

[0045] Additionally, on the rear side of the main frame 15, and on the rear frame 22 located in the transverse direction of the fuselage (see reference...) Figure 2 The rear wheel gearbox 11a is installed on the left and right sides of the vehicle, and the rear wheels 11 (driving wheels) are respectively installed on the left and right rear axles 11b that protrude outward from the rear wheel gearbox 11a.

[0046] Additionally, on the upper part of the rear frame 22, a left and right linkage support frame 23 for supporting the lifting linkage mechanism 3 is provided protruding upwards. On the lower side of the left and right linkage support frame 23, and between the left and right sides, a pair of lower linkage arms 24 are provided. Between the left and right lower linkage arms 24, a hydraulically operated lifting cylinder 25 (lifting device) is provided.

[0047] An upper connecting arm 26 is provided above the lifting cylinder 25, forming a lifting linkage mechanism 3 as a parallel linkage mechanism. In addition, the left and right lower connecting arms 24, which are connected to the sides of the vehicle body 2 at one end, the lifting cylinder 25, and the other end of the upper connecting arm 26 are mounted on the front of the seedling planting section 4.

[0048] Additionally, an engine 30 is mounted on the main frame 15. The rotational power of the engine 30 is transmitted to the gearbox 13 via the belt drive 21 and HST 14. The rotational power transmitted to the gearbox 13 is then divided into driving power and external output power by the auxiliary transmission mechanism 16 within the gearbox 13.

[0049] Additionally, the rotational power of engine 30 is transmitted to a hydraulic pump (not shown). The hydraulic pressure generated by the hydraulic pump is supplied to HST14 and the power steering mechanism 88 of steering wheel 35 (see reference). Figure 3 ), lifting cylinder 25, etc.

[0050] The external output power from the rotational power output transmitted to the gearbox 13 is transmitted to the planting clutch box 27 located at the rear of the vehicle body 2, and then transmitted from the planting clutch box 27 to the seedling planting section 4 via the planting drive shaft 67.

[0051] On the other hand, left and right drive shafts 42 are provided at the rear of the gearbox 13. The rotational power from the engine 30 is transmitted to the left and right rear wheel gearboxes 11a via the gearbox 13 and the drive shafts 42.

[0052] Furthermore, a side clutch 44 is provided on the upstream side of the left and right drive shafts 42 in the transmission direction, which is used to engage or disengage the power transmission relative to the left and right drive shafts 42 (see reference). Figure 3 ).like Figure 1As shown, a side clutch pedal 43a is provided on the lower front part and the left and right sides of the operator's seat 41 for engaging and disengaging the left and right side clutches 44.

[0053] If the inner side clutch pedal 43a of the left and right side clutch pedals 43a is pressed and the side clutch 44 is disengaged, and the steering wheel 35 is operated to turn the vehicle, the drive rotation of the rear wheel 11 on the inner side of the turn can be completely cut off.

[0054] Therefore, compared with turning based solely on steering wheel 35, the turning radius is reduced, and the starting position of the work row can be appropriately selected according to the farmland conditions, thereby improving the work accuracy.

[0055] This allows the transmission of the rear wheel 11 to the inside of the slewing direction to stop during rotation, reducing the slewing radius and preventing the working position before and after slewing from separating. Therefore, it eliminates the need to readjust the starting position after slewing, improving work efficiency or accuracy.

[0056] Furthermore, in the implementation, the automatic turn control described later is configured such that if the vehicle body 2 is turned by operating the steering wheel 35, the side clutch 44 located on the inside of the turn is disengaged, thereby stopping the transmission to the rear wheel 11 on the inside of the turn.

[0057] An operation panel 38 for operating various functions is located on the upper front side of the vehicle body 2, with a hood 39 mounted on top. The operation panel 38 includes an automatic slewing switch 48 for toggling whether automatic slewing control (described later) is enabled, and a monitor 86 (see reference). Figure 3 )wait.

[0058] In addition, the machine cover 39 is equipped with a steering wheel 35 for controlling the machine body, a gear shift lever 36 for controlling the HST14 or the seedling planting section 4, and a secondary gear shift lever 37 for operating the secondary gear shift mechanism 16.

[0059] Additionally, a front cover 40 that can be opened and closed is provided on the front side of the hood 39. Inside the front cover 40 is a fuel tank or battery, and a linkage mechanism that rotates the left and right front wheels 10 and the lower side of the left and right front wheel end housings 10a when the steering wheel 35 is operated.

[0060] An engine cover 30a is provided on the rear side of the fuselage and above the engine 30, covering the upper and side parts of the engine 30. An operator's seat 41 for the operator to sit on is provided on the upper part of the engine cover 30a.

[0061] A fertilizer applicator 5 is located on the rear side of the operator's seat 41 and the rear end side of the main frame 15. The driving force of the fertilizer applicator 5 is transmitted by a fertilizer transmission mechanism, which is configured to face the fertilizer applicator 5 from the left and right sides of the left and right rear wheel gearboxes 11a.

[0062] Additionally, roughly horizontal step steps 33 are formed on the lower left and right sides of the engine hood 30a and engine hood 39. (As shown) Figure 2 As shown, the step 33 is partially grid-like, so that even if mud or dirt from the shoes of an operator walking on the step 33 falls off, the mud or dirt will fall into the farmland.

[0063] In addition, such as Figure 1 As shown, the seedling transplanter 1 includes a location acquisition device 150. The location acquisition device 150 receives location information from positioning systems such as GPS (Global Positioning System) and GNSS (Global Navigation Satellite System), and generates and acquires the current location information of the machine based on the received location information. The location acquisition device 150 is, for example, mounted on a mounting support 59 and positioned above the traveling vehicle body 2.

[0064] The straight-line control program and the turn control program, generated based on the position information from the position acquisition device 150, are stored in different locations. The straight-line control program is, for example, stored in the straight-line control ECU (Electronic Control Unit) 100a within the position acquisition device 150, and the turn control program is, for example, stored in the turn control ECU 100b housed in the engine hood 39. Furthermore, the straight-line control ECU 100a and the turn control ECU 100b are included in the control device 100 described later (see reference 100). Figure 3 )middle.

[0065] <Control System of Operating Vehicles>

[0066] The following is for reference Figure 3 The control system C of the seedling transplanter 1 is described. Figure 3 This is a block diagram representing the control system C centered on the control device 100 in the seedling transplanter 1. The seedling transplanter 1 is capable of controlling its various parts electronically and is equipped with a control device (hereinafter referred to as a controller) 100 for controlling its various parts.

[0067] The controller 100 includes a processing unit with a CPU (Central Processing Unit), a storage unit with ROM (Read Only Memory) and RAM (Random Access Memory), and an input / output unit, all of which are interconnected and capable of exchanging signals. The storage unit contains computer programs for controlling the seedling transplanter 1. The controller 100 performs its various functions by reading the computer programs stored in the storage unit.

[0068] The controller 100, for example as a drive unit, is connected to a throttle motor 80, hydraulic control valves 81 and 82, a planting clutch working solenoid 83, a side clutch working solenoid 84, an HST motor 85, a scribing lifting motor 87, a steering motor 95, etc.

[0069] The throttle motor 80 increases or decreases the speed of the output shaft of the engine 30 by operating the throttle valve, which regulates the intake air volume of the engine 30. The hydraulic control valve 81 controls the extension and retraction of the lifting cylinder 25. The hydraulic control valve 82 controls the power steering mechanism 88. The solenoid 83 of the drive clutch engages the drive clutch 27a.

[0070] The side clutch working solenoid 84 engages the side clutch 44, which switches the power transmission state to the rear wheel 11. Furthermore, the side clutches 44 are respectively located on the left and right rear wheels 11, and two side clutch working solenoids 84 are provided corresponding to each side clutch 44.

[0071] HST motor 85 changes the tilt angle of the swashplate of HST14 by changing the rotation angle of the trunnion of HST14. Steering motor 95, in the case of automatic swivel control, adjusts the front wheel 10 (refer to...) which serves as the driving wheel. Figure 1 The steering mechanism 95, which controls the steering wheel 35, is driven by a motor. The steering motor 95 rotates the steering wheel 35. The lane divider lifting motor 87 raises and lowers the lane divider 65.

[0072] Additionally, the controller 100 is connected to a speed sensor 90, a control quantity sensor 91, a tilt sensor 92, etc., which serve as detection devices. Two speed sensors 90 are provided corresponding to the left and right rear wheels 11, which are the driving wheels, and detect the speed of the left and right rear wheels 11 respectively. Furthermore, the speed sensors 90 can also detect the speed of the left and right front wheels 10.

[0073] The control input sensor 91 detects the amount of operation of the steering wheel 35, which serves as the steering device, i.e., the amount of operation (rudder angle) of the front wheels 10. Furthermore, the control input is detected in both the left and right directions, based on the condition that the steering wheel 35 operation is zero, i.e., when the vehicle body 2 is traveling straight. The tilt sensor 92 detects the tilt angle of the vehicle body 2.

[0074] In addition, signals are input to the controller 100 from the gear shift lever 36, the auxiliary gear shift lever 37, the automatic lifting switch of the planting section 47, the automatic rotation switch 48, the automatic lifting switch of the marking device 49, etc., as operating signals.

[0075] The automatic raising and lowering switch 47 for the planting section is used to toggle whether the seedling planting section 4 is automatically raised and lowered in conjunction with the operation of the steering wheel 35, i.e., the operation of the front wheels 10. When the automatic raising and lowering switch 47 is on, the control of automatically raising and lowering the seedling planting section 4 in conjunction with the operation is performed. On the other hand, when the automatic raising and lowering switch 47 is off, the control of automatically raising and lowering the seedling planting section 4 in conjunction with the operation is not performed.

[0076] The automatic raising / lowering switch 49 is a switch that toggles whether the automatic raising / lowering of the lane marking device 65 is linked to the operation of the steering wheel 35, i.e., the operation of the front wheels 10. When the automatic raising / lowering switch 49 is on, the automatic raising / lowering of the lane marking device 65 is performed in conjunction with the operation of the steering wheel 35. On the other hand, when the automatic raising / lowering switch 49 is off, the automatic raising / lowering of the lane marking device 65 in conjunction with the operation of the steering wheel 35 is not performed.

[0077] The automatic rotary switch 48 is an illuminated, spring-loaded switch used to toggle the start or stop of automatic rotary rotation. The automatic rotary switch 48 illuminates when activated by the operator and during automatic rotary rotation; it turns off when automatic rotary rotation ends. Conversely, the automatic rotary switch 48 can also be deactivated by the operator during automatic rotary rotation, turning off when automatic rotary rotation stops. This allows the operator to confirm whether automatic rotary rotation is in progress.

[0078] Additionally, the position acquisition device 150 inputs the current position information of the machine body to the controller 100. Based on the position information, the controller 100 executes an autonomous driving mode in which the machine body automatically moves while performing operations. The automatic turn switch 48, speed sensor 90, control quantity sensor 91, steering motor 95, steering wheel 35, and position acquisition device 150 constitute the control system C of the automatic turn mode described later, centered on the controller 100.

[0079] <Autonomous Driving Mode>

[0080] Here, refer to Figure 4The automatic driving (autonomous driving) of the seedling transplanter 1, including automatic rotation in farmland, will be explained. Figure 4 This is an illustration of the autonomous movement of the work vehicle (seedling transplanter 1) in the farmland. Controller 100 (see reference) Figure 3 ) features one-sided feedback front wheel 10 (refer to Figure 1 The amount of control is used to control the steering motor 95 (refer to) Figure 3 To operate the steering wheel 35 (refer to) Figure 3 The autonomous driving mode includes automatic straight driving mode and automatic U-turn mode.

[0081] like Figure 4 As shown, in autonomous driving mode, the seedling transplanter 1 automatically plants seedlings while repeatedly moving straight and turning along a predetermined driving path in the farmland F. Furthermore, as described above, the controller 100 obtains the current position information of the seedling transplanter 1 via a position acquisition device 150 disposed above the vehicle body 2.

[0082] The seedling transplanter 1 plants seedlings while reciprocating within a predetermined work area in farmland F. In this case, for straight-line travel, the controller 100 executes an automatic straight-line mode, thereby automatically traveling along a set straight-line travel path L1. Conversely, for turning travel, the controller 100 executes an automatic turning mode, thereby automatically turning along a set turning travel path L2.

[0083] The straight-line travel path L1 is parallel to the baseline L0, which serves as the driving reference. The baseline L0 is set in the farmland F in the same direction as the planting of the seedlings. The controller 100 obtains the start and end positions of the straight-line travel as the baseline start point (point A) and baseline end point (point B), respectively, and registers the baseline L0 as the line connecting points A and B.

[0084] Additionally, the controller 100 has a first slewing operation mode and a second slewing operation mode as an automatic slewing mode. The controller 100 executes the automatic slewing mode by combining the first slewing operation mode and the second slewing operation mode. Furthermore, if the automatic slewing switch 48 is turned on by the operator, the controller 100 executes the automatic slewing mode.

[0085] In the first rotation operation mode, the controller 100 controls the steering motor 95 such that the amount of steering wheel 35 is adjusted to a predetermined value during the rotation of the seedling transplanter 1. In this case, the controller 100 performs processing independently of the position information acquired by the position acquisition device 150.

[0086] In the second slewing mode, the controller 100 controls the steering motor 95 based on the position information obtained by the position acquisition device 150 during the slewing of the seedling transplanter 1, so that the seedling transplanter 1 reaches any desired position on the slewing travel path L2.

[0087] Thus, the controller 100 has a first rotation operation mode and a second rotation operation mode. During the rotation of the machine body, the first rotation operation mode, which is not based on position information, is executed. Therefore, it is not necessary to use position information for all aspects of the automatic rotation control. Thus, only a portion of the control using position information is needed for automatic rotation, enabling simpler control for automatic rotation.

[0088] Furthermore, in automatic rotation mode, if the controller 100 deviates from the rotation path L2 and rotates (large circle or small circle) during the rotation of the seedling transplanter 1, it corrects the position based on the position acquisition device 150.

[0089] <Automatic Rotation Mode of the First Embodiment>

[0090] The following is for reference Figures 5-8 The automatic rotation mode of the first embodiment will be described. Figure 5 This is an explanatory diagram of the automatic slewing control (automatic slewing mode) of the first embodiment. Figure 6 This is a flowchart illustrating the processing sequence of the automatic rotation control (automatic rotation mode) in the first embodiment.

[0091] in addition, Figure 7 This is a flowchart showing the control process sequence for initiating automatic slewing control (automatic slewing mode). Figure 8 It is a flowchart showing the control processing sequence for transitioning from the first rotary motion mode to the second rotary motion mode.

[0092] like Figure 5 As shown, in the automatic rotation mode of the first embodiment, if the operator presses the automatic rotation switch 48 (see reference 1) when the position is close to the preset desired rotation start position (in the case of agricultural machinery such as seedling transplanter 1, it is also the end position of the operation in one row) P1, the automatic rotation switch 48 is activated. Figure 3 In automatic straight-line mode, the seedling transplanter 1 that has entered will start to turn around automatically.

[0093] If automatic rotation begins, the transplanting machine 1 starts traveling based on the first rotation movement mode. In the first rotation movement mode, the transplanting machine 1 travels along the rotation path L2, and ends its travel based on the first rotation movement mode at the end position (mode end position) P3 on the rotation path L2. If the transplanting machine 1 ends its travel based on the first rotation movement mode, it starts traveling based on the second rotation movement mode.

[0094] In the second rotary motion mode, the seedling transplanter 1 moves along the straight travel path L1 of the next row while gradually correcting its position at the pre-set desired end position of the rotary motion (which is also the start position of the next row in the case of agricultural machinery such as the seedling transplanter 1). If the movement based on the second rotary motion mode ends, the movement of the next row begins in the automatic straight travel mode.

[0095] like Figure 6 As shown, in the first embodiment, the controller 100 determines whether the automatic rotation switch 48 has been turned on (step S101). If the automatic rotation switch 48 has been turned on (step S101: yes), the controller 100 determines whether the seedling transplanter 1 has reached the rotation start position P1 (step S102). If the controller 100 determines that the rotation start position P1 has been reached (step S102: yes), then the execution of the first rotation operation mode begins (step S103).

[0096] In step S101, if the automatic rotary switch 48 is not "connected" (step S101: No), the controller 100 repeatedly performs this process until a "connection" operation is performed. Additionally, in step S102, if the seedling transplanter 1 has not reached the rotary start position P1 (step S102: No), the controller 100 repeatedly performs this process until the rotary start position P1 is reached.

[0097] Next, the controller 100 determines whether the seedling transplanter 1 has reached the end position (mode end position) P3 of the first rotary action mode (step S104). If the mode end position P3 has been reached (step S104: yes), the controller 100 ends the execution of the first rotary action mode (step S105) and begins the execution of the second rotary action mode (step S106).

[0098] In step S104, if the seedling transplanter 1 has not reached the mode end position P3 (step S104: no), the controller 100 repeatedly enters the process until the mode end position P3 is reached.

[0099] Next, the controller 100 determines whether the seedling transplanter 1 has reached the end position of the second rotary operation mode, that is, the rotary end position P2 (step S107). If the rotary end position P2 has been reached (step S107: yes), the controller 100 ends the execution of the second rotary operation mode (step S108), and ends the rotary operation mode.

[0100] Here, in the first turning operation mode, the controller 100 controls the steering motor 95 (see reference) in a manner where the orientation of the machine body is 0 degrees when traveling straight and 70 degrees when turning to either the left or right. Figure 3 If the orientation of the machine body becomes 70 degrees, the controller 100 controls the steering motor 95 to start returning to straight driving, that is, the orientation of the machine body becomes 90 degrees.

[0101] When transitioning from the first turning operation mode to the second turning operation mode, the controller 100 controls the steering motor 95 to enter, for example, a 0-20 degree range for the machine's orientation along the next straight travel path L1. By pre-positioning the machine's orientation within the 0-20 degree range at the start of the second turning operation mode, the controller 100, based on the position acquisition device 150 (see reference 150), enables the machine to move within this range during the second turning operation mode. Figure 3 The obtained position information is used to correct the orientation of the machine so that it travels along the straight path L1, thereby completing the turning motion.

[0102] In step S107, if the seedling transplanter 1 has not reached the end position P2 of rotation (step S107: No), the controller 100 repeatedly performs this process until the end position P2 of rotation is reached. If the controller 100 ends the rotation mode, it begins the execution of the automatic straight-line mode.

[0103] In addition, such as Figure 7 As shown, controller 100 in Figure 6 In the processing shown (step S101), based on the position information obtained by the position acquisition device 150 during automatic straight-line travel, it is determined whether the distance from the current position to the turning start position P1 of the seedling transplanter 1 is less than a predetermined distance D (step S1011). The controller 100 calculates the travel distance based on the position measurement information and determines whether the distance from the current position to the turning start position P1 of the seedling transplanter 1 is less than the predetermined distance D. In addition, the controller 100 can also calculate the travel distance based on the rotational speed of the driving wheels.

[0104] The controller 100 makes the above determination based on the travel distance of the preceding process of the planting process that precedes the current straight-line driving process.

[0105] The starting position P1 of the turn in this planting process can be predicted to be near the straight-ahead travel distance of the previous process. For example, in this planting process, the actual starting position of the turn can be predicted to be within ±5m of the travel distance in the previous process.

[0106] Therefore, the controller 100 predicts the turning start position P1 based on the travel distance in the previous process. Specifically, if the position in the previous process that is the travel distance is predicted as the turning start position P1, and the distance from the seedling transplanter 1 from its current position to the turning start position P1 is less than a predetermined distance D, the controller 100 determines that the straight-line distance in this planting process is near the turning position, i.e., at the edge of the field.

[0107] In addition, the starting position P1 of the rotation can also be identified by coordinates based on the position measurement information.

[0108] If the distance to the starting position P1 is less than or equal to a predetermined distance D (step S1011: Yes), and the automatic rotary switch 48 is "turned on", the controller 100 executes the first rotary operation mode (step S1012).

[0109] In the process of step S1011, if the distance to the starting position P1 exceeds the predetermined distance D (step S1011: no), even if the automatic rotary switch 48 is "turned on", the controller 100 will not execute the first rotary operation mode (step S1013), but will continue the automatic straight-line mode.

[0110] Additionally, the end position P3 of the first rotational motion mode is based on the speed sensor 90 (reference). Figure 3 The rear wheel 11 detected (counted) (refer to) Figure 1 The speed is set by the rotational speed. For example... Figure 8 As shown, if controller 100 is in Figure 6 In the process shown in step S103, the execution of the first rotational action mode begins, and the counting of the speed of the rear wheel 11 begins (step S1031). It is then determined whether the speed of the rear wheel 11 has reached a predetermined value (count value) (step S1032).

[0111] When the speed of the rear wheel 11 reaches the predetermined count value (step S1032: Yes), the controller 100 determines that the end position P3 has been reached and ends the execution of the first rotation operation mode and executes the second rotation operation mode (step S1033). In the process of step S1032, if the speed of the rear wheel 11 is not the predetermined count value (step S1032: No), the controller 100 repeats this process until it reaches the predetermined count value.

[0112] According to the first embodiment described above, by executing a first rotation operation mode when the seedling transplanter 1 starts rotating and a second rotation operation mode when the rotation ends, automatic rotation can be performed with simpler control.

[0113] In addition, the counting of the speed of the rear wheel 11 begins with the start of the first slewing operation mode. If the speed of the rear wheel 11 reaches the predetermined count value, the operation mode is switched to the second slewing operation mode. Therefore, the control using position information is only a part of the automatic slewing, and automatic slewing can be performed with simple control.

[0114] Furthermore, if the distance from the current position to the rotation start position P1 of the seedling transplanter 1 is short, the first rotation operation mode will be executed if the automatic rotation switch 48 is turned on. On the other hand, if the distance from the current position to the rotation start position P1 of the seedling transplanter 1 is long, the first rotation operation mode will not be executed even if the automatic rotation switch 48 is operated. In this way, for example, even if the automatic rotation switch 48 is operated outside the rotation start position P1, such as near the center of the farmland (i.e., accidental operation), the first rotation operation mode will not be executed, thereby preventing accidental operation.

[0115] In addition, if the second slewing motion mode towards the end position P2 ends, it will switch to the automatic straight-line mode as before and start automatic straight-line movement, thus enabling the operation to continue and improving workability.

[0116] Furthermore, in the first embodiment, the second rotation operation mode is executed after the first rotation operation mode is executed. However, as a variation, the first rotation operation mode may be executed after the second rotation operation mode to reach the rotation end position P2.

[0117] <Automatic Rotation Mode of the Second Embodiment>

[0118] The following is for reference Figure 9 as well as Figure 10 The automatic rotation mode of the second embodiment will be described. Figure 9 This is an explanatory diagram of the automatic slewing control (automatic slewing mode) of the second embodiment. Figure 10 This is a flowchart illustrating the processing sequence of the automatic rotation control (automatic rotation mode) in the second embodiment.

[0119] like Figure 9 As shown, in the automatic rotation mode of the second embodiment, similar to the first embodiment described above, if the seedling transplanter 1, which is traveling in automatic straight mode, is approaching the predetermined desired rotation start position P1, the operator presses the automatic rotation switch 48 (see reference 48). Figure 3 If the current value is 0, it will start to rotate automatically.

[0120] If automatic rotation begins, the seedling transplanter 1 starts traveling based on the second rotation movement mode (first time) and travels along the rotation path L2. The seedling transplanter 1 ends its travel based on the second rotation movement mode at the end position (mode end position) P4 on the rotation path L2.

[0121] If the seedling transplanter 1 finishes traveling in the second rotary motion mode based on the first rotation, it begins traveling in the first rotary motion mode. The seedling transplanter 1 ends traveling in the first rotary motion mode at the mode end position P5 on the rotary travel path L2. If the seedling transplanter 1 finishes traveling in the first rotary motion mode, it begins traveling in the second rotary motion mode (second time).

[0122] In the second rotation mode, the transplanting machine 1 moves along the straight path L1 of the next row while gradually correcting its position at the pre-set desired end position P2. If the movement based on the second rotation mode ends, the movement in the next row begins in automatic straight mode.

[0123] like Figure 10 As shown, in the second embodiment, the controller 100 determines whether the automatic rotary switch 48 has been "connected" (step S201). If the automatic rotary switch 48 has been "connected" (step S201: yes), the controller 100 determines whether the seedling transplanter 1 has reached the rotary start position P1 (step S202). If it is determined that the rotary start position P1 has been reached (step S202: yes), the controller 100 begins the execution of the second rotary operation mode (first time) (step S203).

[0124] In step S201, if the automatic rotary switch 48 is not "connected" (step S201: No), the controller 100 repeatedly performs this process until a "connection" operation is performed. Furthermore, in step S202, if the seedling transplanter 1 has not reached the rotary start position P1 (step S202: No), the controller 100 repeatedly performs this process until the rotary start position P1 is reached.

[0125] Next, the controller 100 determines whether the seedling transplanter 1 has reached the end position (mode end position) P4 of the first second rotation operation mode (step S204). If the mode end position P4 has been reached (step S204: yes), the controller 100 ends the execution of the first second rotation operation mode (step S205) and begins the execution of the first rotation operation mode (step S206).

[0126] In step S204, if the seedling transplanter 1 has not reached the mode end position P4 (step S204: no), the controller 100 repeatedly performs this process until the mode end position P4 is reached.

[0127] Next, the controller 100 determines whether the seedling transplanter 1 has reached the end position (mode end position) P5 of the first rotary action mode (step S207). If the mode end position P5 has been reached (step S207: yes), the controller 100 ends the execution of the first rotary action mode (step S208) and begins the execution of the second rotary action mode (second time) (step S209).

[0128] In step S207, if the seedling transplanter 1 has not reached the mode end position P5 (step S207: no), the controller 100 repeatedly enters the process until the mode end position P5 is reached.

[0129] Next, the controller 100 determines whether the seedling transplanter 1 has reached the end position of the second rotation operation mode, that is, the rotation end position P2 (step S210). If the rotation end position P2 has been reached (step S210: yes), the controller 100 ends the execution of the second rotation operation mode (step S211) and ends the rotation operation mode.

[0130] In step S210, if the seedling transplanter 1 has not reached the end position P2 of rotation (step S210: No), the controller 100 repeatedly performs this process until the end position P2 of rotation is reached. If the controller 100 ends the rotation mode, it begins the execution of the automatic straight-line mode.

[0131] Here, when the controller 100 transitions from the first turning operation mode to the second turning operation mode, it controls the steering motor 95 so that the orientation of the vehicle body relative to the straight travel path L1 of the next row enters, for example, a range of 0 to 20 degrees. By bringing the orientation of the vehicle body into the 0 to 20-degree range at the beginning of the second turning operation mode, the controller 100, based on the position acquisition device 150 (see reference 150), enables the vehicle body to maintain its orientation within the 0 to 20-degree range during the second turning operation mode. Figure 3 The obtained position information is used to correct the orientation of the machine so that it travels along the straight path L1, thereby completing the turning motion.

[0132] Furthermore, in the second embodiment, similar to the first embodiment, the controller 100 in... Figure 10 In the process shown (step S201), based on the location acquisition device 150 (refer to...) Figure 3 The position information obtained during automatic straight-line movement determines whether the distance from the current position of the seedling transplanter 1 to the starting position of the turn P1 is less than the predetermined distance D.

[0133] If the distance to the starting position P1 is less than or equal to a predetermined distance D, and the automatic rotary switch 48 is "turned on", the controller 100 will execute the second rotary operation mode for the first time.

[0134] If the distance to the starting position P1 exceeds the predetermined distance D, even if the automatic slewing switch 48 is "turned on", the controller 100 will not execute the first slewing action mode, but will continue the automatic straight-line mode.

[0135] Furthermore, in the second embodiment, similar to the first embodiment, the end position P5 of the first rotational motion mode is based on the speed sensor 90 (refer to...). Figure 3 ) Rear wheel 11 (refer to) Figure 1 The speed is set by the rotational speed. Figure 10 In the process shown in (step S206), if the controller 100 starts executing the first rotational operation mode, it will start counting the rotational speed of the rear wheel 11 and determine whether the rotational speed of the rear wheel 11 has reached the predetermined count value.

[0136] When the speed of the rear wheel 11 reaches the predetermined count value, the controller 100 determines that the mode end position P5 has been reached and ends the execution of the first rotation operation mode, and then executes the second rotation operation mode. When the speed of the rear wheel 11 does not reach the predetermined count value, the controller 100 repeats this process until it reaches the predetermined count value.

[0137] According to the second embodiment described above, by executing the first rotation operation mode when the seedling transplanter 1 starts rotating and the second rotation operation mode when the rotation ends, automatic rotation can be performed with simpler control.

[0138] Furthermore, since the first turning action mode is executed during the straight-line movement of the machine in the middle of the turning after the second turning action mode ends, the driving error caused by the sliding of the rear wheel 11 in the first turning action mode can be reduced, so as a whole, the turning stroke can be reliably turned automatically.

[0139] In addition, the speed of the rear wheel 11 is counted when the first slewing operation mode begins. If the speed of the rear wheel 11 reaches the predetermined count value, the operation mode is switched to the second slewing operation mode. Therefore, the control using position information is only part of the automatic slewing, and automatic slewing can be performed with simple control.

[0140] Furthermore, if the distance from the current position to the rotation start position P1 of the seedling transplanter 1 is short, the first rotation operation mode will be executed if the automatic rotation switch 48 is turned on. On the other hand, if the distance from the current position to the rotation start position P1 of the seedling transplanter 1 is long, the first rotation operation mode will not be executed even if the automatic rotation switch 48 is operated. In this way, even if the automatic rotation switch 48 is operated outside the rotation start position P1, such as near the center of the farmland (i.e., accidental operation), the first rotation operation mode will not be executed, thereby preventing accidental operation.

[0141] In addition, if the second rotation mode towards the end position P2 ends, the system will switch to automatic straight-line mode and start automatic straight-line movement, thus enabling the operation to continue and improving workability.

[0142] Furthermore, in the second embodiment, after executing the second rotation operation mode, the first rotation operation mode is executed, and then the second rotation operation mode is executed again. However, as a variation, for example, the first rotation operation mode can be executed, followed by the second rotation operation mode, and then the first rotation operation mode is executed again to reach the rotation end position P2.

[0143] Alternatively, the first rotation mode and the second rotation mode can be executed two or more times respectively.

[0144] <Automatic Rotation Mode of the Third Embodiment>

[0145] The following is for reference Figure 11 as well as Figure 12 The automatic rotation mode of the third embodiment will be described. Figure 11 This is an explanatory diagram of the automatic rotation control (automatic rotation mode) of the third embodiment. Figure 12 This is a flowchart illustrating the processing sequence of the automatic rotation control (automatic rotation mode) in the third embodiment.

[0146] like Figure 11 As shown, the third embodiment is an automatic reversing mode in which the seedling transplanter 1 travels straight to the edge of the field and then reverses a predetermined distance before turning back, which is called a reversing reversing with sound.

[0147] In the automatic rotation mode of the third embodiment, if the seedling transplanter 1, which is traveling to the edge of the field in automatic straight-line mode, is operated by the operator to reverse on the gear shift lever (referred to as the HST lever) 36 (see reference)... Figure 3 If the operation route is obtained in the next row (turning travel path L2 and straight travel path L1 in the next row), automatic turning including reverse movement will begin.

[0148] If automatic rotation begins, the transplanting machine 1 will reverse a predetermined distance and then begin traveling based on the second rotation movement mode (first time), along the rotation travel path L2. The transplanting machine 1 will end its travel based on the second rotation movement mode at the end position (mode end position) P6 on the rotation travel path L2.

[0149] If the seedling transplanter 1 finishes traveling in the second rotary motion mode based on the first rotation, it begins traveling in the first rotary motion mode. The seedling transplanter 1 ends traveling in the first rotary motion mode at the mode end position P7 on the rotary travel path L2. If the seedling transplanter 1 finishes traveling in the first rotary motion mode, it begins traveling in the second rotary motion mode (second time).

[0150] In the second rotation mode, the transplanting machine 1 moves along the straight path L1 of the next row while gradually correcting its position at the pre-set desired end position P2. If the movement based on the second rotation mode ends, the movement in the next row begins in automatic straight mode.

[0151] like Figure 12 As shown, in the third embodiment, the controller 100 determines whether the HST lever 36 has been operated to the "reverse" side (step S301). If the HST lever 36 has been operated to the "reverse" side (step S301: yes), the controller 100 starts the reversal of the seedling transplanter 1 (step S302).

[0152] The controller 100 determines whether the seedling transplanter 1 has reached the rotation start position P1 (step S303). If it is determined that the rotation start position P1 has been reached (step S303: yes), the controller 100 ends the retraction of the seedling transplanter 1 (step S304) and begins the execution of the second rotation action mode (first time) (step S305).

[0153] In step S301, if the HST lever 36 is not operated to the "reverse" side (step S301: No), the controller 100 repeats this process until it is operated to the "reverse" side. Additionally, in step S303, if the seedling transplanter 1 has not reached the rotation start position P1 (step S303: No), the controller 100 repeats this process until it reaches the rotation start position P1.

[0154] Next, the controller 100 determines whether the seedling transplanter 1 has reached the end position (mode end position) P6 of the first second rotation operation mode (step S306). If the mode end position P6 has been reached (step S306: yes), the controller 100 ends the execution of the first second rotation operation mode (step S307) and begins the execution of the first rotation operation mode (step S308).

[0155] In step S306, if the seedling transplanter 1 has not reached the mode end position P5 (step S306: no), the controller 100 repeatedly performs this process until the mode end position P6 is reached.

[0156] Next, the controller 100 determines whether the seedling transplanter 1 has reached the end position (mode end position) P7 of the first rotary action mode (step S309). If the mode end position P7 has been reached (step S309: yes), the controller 100 ends the execution of the first rotary action mode (step S310) and begins the execution of the second rotary action mode (second time) (step S311).

[0157] In step S309, if the seedling transplanter 1 has not reached the mode end position P7 (step S309: no), the controller 100 repeatedly performs this process until the mode end position P7 is reached.

[0158] Next, the controller 100 determines whether the seedling transplanter 1 has reached the end position of the second rotation operation mode, that is, the rotation end position P2 (step S312). If the rotation end position P2 has been reached (step S312: yes), the controller 100 ends the execution of the second rotation operation mode (step S313), thereby ending the rotation operation mode.

[0159] In step S312, if the seedling transplanter 1 has not reached the end position P2 of rotation (step S312: No), the controller 100 repeatedly performs this process until the end position P2 of rotation is reached. If the controller 100 ends the rotation mode, it starts the execution of the automatic straight-line mode.

[0160] Here, when the controller 100 transitions from the first turning operation mode to the second turning operation mode, it controls the steering motor 95 so that the orientation of the vehicle body relative to the straight travel path L1 of the next row enters, for example, a range of 0 to 20 degrees. By bringing the orientation of the vehicle body into the 0 to 20-degree range at the beginning of the second turning operation mode, the controller 100, based on the position acquisition device 150 (see reference 150), enables the vehicle body to maintain its orientation within the 0 to 20-degree range during the second turning operation mode. Figure 3 The obtained position information is used to correct the orientation of the machine so that it travels along the straight path L1, thereby completing the turning motion.

[0161] Furthermore, in the third embodiment, similar to the first and second embodiments, the end position P7 of the first rotational motion mode is based on the speed sensor (90) (see reference). Figure 3 ) Rear wheel 11 (refer to) Figure 1 The speed is set by the rotational speed. Figure 12 In the process shown in step S308, if the controller 100 starts executing the first rotational operation mode, it will start counting the rotational speed of the rear wheel 11 and determine whether the rotational speed of the rear wheel 11 has reached the predetermined count value.

[0162] When the rotational speed of the rear wheel 11 reaches a predetermined count value, the controller 100 determines that the mode end position P7 has been reached and ends the execution of the first rotational action mode, and then executes the second rotational action mode. When the rotational speed of the rear wheel 11 does not reach the predetermined count value, the controller 100 repeats this process until it reaches the predetermined count value.

[0163] Furthermore, even during the initial reverse movement of the slewing motion, the controller 100 determines whether the slewing start position P1 has been reached based on the rotational speed of the rear wheel 11, which serves as the driving wheel.

[0164] According to the third embodiment described above, similar to the first and second embodiments, by executing the first rotation operation mode at the start of rotation of the seedling transplanter 1 and the second rotation operation mode at the end of rotation, automatic rotation can be performed with simpler control.

[0165] Furthermore, since the first turning action mode is executed when the machine is moving straight during the middle of the turning process after the second turning action mode ends, the travel error caused by the sliding of the rear wheel 11 in the first turning action mode can be reduced, and automatic turning can be reliably performed as a whole as the turning stroke.

[0166] In addition, the speed of the rear wheel 11 is counted when the first slewing operation mode begins. If the speed of the rear wheel 11 reaches the predetermined count value, the operation mode is switched to the second slewing operation mode. Therefore, the control using position information is only one part of the automatic slewing, and automatic slewing can be performed with simple control.

[0167] In addition, if the second rotation mode towards the end position P2 ends, the system will switch to automatic straight-line mode and start automatic straight-line movement, thus enabling the operation to continue and improving workability.

[0168] Furthermore, in the third embodiment, as a variation, for example, the second rotation operation mode may be executed after the first rotation operation mode is executed, and the first rotation operation mode is executed again to reach the rotation end position P2.

[0169] Alternatively, an automatic slewing mode can be used, which executes the first slewing motion mode and the second slewing motion mode twice or more.

[0170] Furthermore, in the first to third embodiments, the controller 100 preferably sets an upper limit on the speed of the seedling transplanter 1 in automatic rotation mode to limit the vehicle speed. This ensures stable rotation and safety. Additionally, if the controller 100 determines that rotation has ended based on position information from the position acquisition device 150, it releases the speed limit and sets the speed to the position corresponding to the shift lever (HST lever) 36.

[0171] Furthermore, in the first to third embodiments, the controller 100 sets the rotational speed of the rear wheel 11 in a variable manner. Additionally, if the operator "raises" the assist lever during the execution of automatic straight-ahead mode or automatic turn-around mode, the controller 100 deactivates each mode.

[0172] Furthermore, in the first to third embodiments, when the controller 100 is operated by the operator to "disengage" the Z-direction during the execution of the automatic rotation mode, the automatic rotation mode is deactivated. Additionally, during the execution of the automatic rotation mode, when the operator operates the automatic lifting switch 49 of the marking machine (see reference...)... Figure 3 If a "disconnect" operation is performed, the controller 100 will deactivate the automatic rotation mode.

[0173] Furthermore, in the first to third embodiments, during the execution of the automatic rotation mode, the operator moves the HST lever (gear shift lever) 36 (see reference) Figure 3 When the steering wheel is moved to the "reverse" position, the controller 100 deactivates the automatic turn mode. Additionally, during automatic turn mode, if the operator operates the steering wheel 35 (refer to...), the automatic turn mode will deactivate. Figure 3 In the event of this, controller 100 deactivates the automatic slewing mode.

[0174] Furthermore, in the first to third embodiments, during the execution of the automatic rotation mode, when the seedling transplanter 1 stops or the engine 30 (refer to...) Figure 1 When the machine stops, the controller 100 temporarily interrupts (retains) the automatic rotation mode. Additionally, during the execution of the automatic rotation mode, if the seedling transplanter 1 stops or the engine 30 stops, the controller 100 can also control the automatic rotation mode to be stopped.

[0175] Furthermore, in the first to third embodiments, if the field alarm release switch is pressed, the controller 100 will release the field stop when the field alarm is activated. Additionally, the controller 100 can also display whether automatic rotation is possible on the monitor 86 (see reference). Figure 3 Furthermore, in cases where automatic rotation is not possible, the controller 100 can, for example, display a prompt on the monitor 86.

[0176] Furthermore, in the third embodiment, even if the seedling transplanter 1 stops during reversal, the controller 100 will not terminate the automatic rotation mode. Therefore, even if the machine stops during reversal due to an accident such as seedling sticking together, it can continue to rotate automatically.

[0177] In addition, in the first to third embodiments, the automatic rotation mode (in the third embodiment, the automatic rotation mode excludes the backward motion) can be configured to be completed only by the first rotation motion mode, or it can be configured to be completed only by the second rotation motion mode.

[0178] Furthermore, in the first to third embodiments, the start of automatic rotation may also be the timing of the "lifting action" that causes the seedling planting section 4 to rise and fall. That is, the automatic rotation switch 48 may also be a switch that raises the seedling planting section 4 through the operator's operation, or it may be a detection unit that detects the rise of the seedling planting section 4 or detects the start of control that raises the seedling planting section 4.

[0179] Alternatively, the start of automatic rotation can also be the time when the power transmission to the seedling planting device 55 is "disconnected", the time when the output device 71 of the fertilization device 5 stops, or the time when the power transmission to the land preparation rotating component 63 is "disconnected".

[0180] Thus, the automatic rotation can begin whenever the drive of the seedling planting section 4 or other farmland operation device is "disconnected".

[0181] Alternatively, the working vehicle 1 can also be a tractor. In this case, the agricultural working device is a rotating body or the like. The aforementioned slewing control can also be applied during the slewing of the tractor.

[0182] Further effects or variations can be readily derived by those skilled in the art. Therefore, the invention is not limited to the specific, detailed, and representative embodiments described and illustrated above. Thus, various modifications can be made without departing from the spirit or scope of the invention as defined by the claims and their equivalents.

Claims

1. A working vehicle, characterized in that, have: The vehicle body (2) is equipped with the following: driving wheels (10, 11); a steering device (35) that adjusts the control amount of the driving wheels (10); a motor (95) that drives the steering device (35); a position acquisition device (150) that receives position information from the position measuring mechanism and obtains the current position information of the vehicle body based on the received position information; and a control device (100) that controls the motor (95). The control device (100) has a first rotation operation mode and a second rotation operation mode during the rotation of the machine body. The first rotation operation mode is a mode in which the motor (95) is controlled to a predetermined value regardless of the position information. The second rotation operation mode is a mode in which the motor (95) is controlled based on the position information to reach the desired orientation of the machine body on the rotation travel path (L2). It also includes a detection device (90) for detecting the rotational speed of the aforementioned driving wheel (11). The detection device (90) starts detecting the rotational speed as the first rotational operation mode begins. If the rotational speed becomes a predetermined value, the control device (100) switches to the second rotational operation mode.

2. The working vehicle according to claim 1, characterized in that, The control device (100) has an automatic straight-line mode that causes the machine to travel along a straight-line travel path (L1), and switches to the automatic straight-line mode when the second turning action mode toward the desired turning end position (P2) ends.

Images