JP2023004465A - work vehicle - Google Patents

Abstract

To provide a work vehicle capable of accurately detecting a slip of travelling wheels while turning in a farm field by turning control.SOLUTION: A work vehicle includes a travelling vehicle, a work machine for executing work in a farm field, position information acquisition means for acquiring position information on the travelling vehicle, and yaw direction angular speed detection means for detecting a yaw direction angular speed of the travelling vehicle. The travelling vehicle includes travelling wheels, a steering wheel for steering the travelling wheels, a motor for rotating the steering wheel, and control means for executing turning control to drive the motor and turn the work vehicle. The control means calculates a correlation value indicating a degree of a slip of the travelling wheels from an angular speed in a yaw direction of the travelling vehicle in turning.SELECTED DRAWING: Figure 6

Description

The present invention relates to working vehicles such as rice transplanters and tractors.

Conventionally, a work vehicle (hereinafter simply referred to as "vehicle ) is known.

For example, in Patent Document 1, when performing agricultural work while traveling straight on a field, a steering wheel is automatically driven based on the control of a controller (control device 200) to assist a work vehicle to travel straight. In addition, a work vehicle (rice transplanter) is disclosed that automatically drives a steering wheel even when the work vehicle turns over a field. Hereinafter, the control that automatically drives the steering wheel so that the work vehicle runs straight on the field is referred to as "straight control", and the steering wheel is automatically driven so that the work vehicle turns over the field. The control is called "turning control".

The work vehicle disclosed in Patent Document 1 is provided with a rear wheel rotation sensor that detects the number of revolutions of the rear wheels. , as disclosed in FIG. 8 of Patent Document 2, since the rear wheel on the inner side of the turn, which is in an idle state with the clutch disengaged, does not rotate, the rear wheel rotation sensor detects the slip of the running wheel (directly , non-rotation of the inner rear wheel in turns) can be detected. At this time, the work vehicle, like the work vehicle disclosed in Patent Document 2, automatically engages the clutch to drive the rear wheels on the inner side of the turn, or automatically differentially locks the left and right front wheels. The force can be increased to eliminate the slip of the running wheels.

JP 2021-069293 JP 2012-228913

However, when the work vehicle turns, depending on the state of the field, the driving force is weakened as a result of the running wheels slipping, and the work vehicle turns on the spot without moving forward (in other words, on the spot). In this case, when turning, the rear wheels located on the inside also rotate, so the rear wheel rotation sensor can detect the slip of the running wheels. It was difficult.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a work vehicle capable of accurately detecting a slip of a running wheel while turning on a field by turning control.

running vehicle and
a working machine that is attached to the traveling vehicle and performs work in a field;
a positional information acquiring means for acquiring positional information of the traveling vehicle;
A work vehicle comprising yaw direction angular velocity detection means for detecting an angular velocity in the yaw direction of the traveling vehicle,
The traveling vehicle has traveling wheels, a steering wheel that steers the traveling wheels, a motor that rotates the steering wheel, and control means that controls turning of the work vehicle by driving the motor,
The control means is achieved by a work vehicle characterized by calculating a correlation value representing the degree of slip of the running wheels from the angular velocity in the yaw direction of the running vehicle during turning.

According to the present invention, the correlation value representing the degree of slip of the running wheels can be calculated from the angular velocity in the yaw direction of the running vehicle during turning. For example, even when the vehicle turns on the spot, it is possible to accurately detect the slip of the running wheels.

In a preferred embodiment of the invention,
The correlation value is the difference between the angular velocity in the yaw direction of the running vehicle during actual turning and the ideal angular velocity in the yaw direction of the running vehicle during turning for turning to the target position.

In a further preferred embodiment of the invention,
In turning control, the control means drives the motor to change the steering angle of the steering wheel to a predetermined steering angle, and then rotates the steering wheel toward a neutral position by an angle corresponding to the correlation value. switchback control is performed.

According to this preferred embodiment of the present invention, in turning control, the steering wheel is turned back toward the neutral position by an angle corresponding to the calculated correlation value representing the degree of slip of the running wheels. Therefore, it is possible to prevent the work vehicle from making an excessively small turn due to the slip of the traveling wheels, and turn the work vehicle to an appropriate position.

In addition, since it is possible to turn at a steering angle that takes into consideration the slip of the running wheels, there is no need to set a running route when turning and to frequently rotate the steering wheel along the running route. The behavior of the body (running vehicle) can be stabilized.

In a further preferred embodiment of the invention,
In addition, equipped with a monitor,
The control amount of the motor when rotating the steering wheel toward the neutral position can be increased or decreased on the monitor.

According to this preferred embodiment of the present invention, in turning control, the amount of rotation (turning amount) when the steering wheel is turned toward the neutral position (turned back) according to the correlation value representing the degree of slip of the running wheels. Since the return amount) can be increased or decreased, the position of the work vehicle after turning can be easily adjusted on the monitor.

In a further preferred embodiment of the invention,
A control value used to calculate the control amount of the motor is set on the monitor so that the control amount can be increased or decreased,
When the minimum value that can be set as the control value is set, the control means does not perform the switchback control,
When the maximum value that can be set as the control value is set, the control means rotates the steering wheel to the neutral position side by twice the angle compared to when 0 is set as the control value. move.

In a further preferred embodiment of the invention,
Different control values can be set on the monitor depending on whether the work vehicle turns to the left or to the right.

According to this preferred embodiment of the present invention, different control values can be set on the monitor for turning to the left and for turning to the right. When the field conditions are different between the other headlands, the position of the work vehicle after turning can be appropriately adjusted independently at each headland.

In a further preferred embodiment of the invention,
A parameter used for calculating the ideal angular velocity can be changed according to the position of the position information acquisition means.

According to this preferred embodiment of the present invention, the parameters used for calculating the ideal angular velocity can be changed according to the position of the position information acquisition means such as the GNSS receiver. By changing the parameters when the position is moved, an accurate ideal angular velocity can be calculated, and a correlation value representing the degree of slip of the running wheels can be accurately calculated.

In a further preferred embodiment of the present invention, in turning control, the control means drives the motor to change the rudder angle of the steering wheel to a predetermined rudder angle. to adjust the timing of starting to rotate the steering wheel toward the neutral position when finishing the operation.

According to this preferred embodiment of the present invention, in turning control, the timing of turning the steering wheel back to the neutral position when turning is completed is adjusted in accordance with the calculated correlation value representing the degree of slip of the running wheels. With this configuration, it is possible to prevent the work vehicle from making an excessively small turn due to slippage of the traveling wheels.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the work vehicle which can detect the slip of a driving|running|working wheel accurately, while turning on a field by turning control.

FIG. 1 is a schematic left side view of a working vehicle according to a preferred embodiment of the invention. 2 is a schematic plan view of the work vehicle shown in FIG. 1. FIG. FIG. 3 is a block diagram of the control system, detection system, input system and drive system of the work vehicle shown in FIG. 4 is a partially enlarged view of the forward/reverse lever shown in FIG. 1. FIG. FIG. 5 is a schematic plan view showing a route along which the work vehicle shown in FIG. 1 travels while planting seedlings in a field. FIG. 6 is a flow chart showing the procedure of turning control by the controller of the work vehicle shown in FIG. FIG. 7 is a schematic plan view showing the relationship between the plurality of steps shown in FIG. 6 and the direction (orientation) of the traveling vehicle. FIG. 8 is a drawing showing a control value setting screen displayed on the monitor when turning control is performed. FIG. 9 is a schematic front view showing how the line marker according to the embodiment shown in FIG. 1 is adjusted in angle according to the depth of the field or the tilt of the machine. FIG. 10(a) is a schematic side view showing an auxiliary seedling frame of a conventional work vehicle, and FIG. 10(b) is a view near the auxiliary seedling frame on the left side of the work vehicle according to another preferred embodiment of the present invention. is a schematic side view of the. FIG. 11 is a schematic side view of the vicinity of the right auxiliary seedling frame according to the embodiment shown in FIG. 10(b). FIG. 12 is a schematic side view of the vicinity of the left auxiliary seedling frame according to still another preferred embodiment of the present invention. 13 is a schematic side view of the vicinity of the right auxiliary seedling frame according to the embodiment shown in FIG. 12; FIG. 14 is a schematic side view of the vicinity of the frame supporting the auxiliary seedling frame according to the embodiment shown in FIG. 12; FIG. 15 is a partially enlarged view of the vicinity of the rack gear of the longitudinal position adjusting mechanism shown in FIG. 14. FIG. FIG. 16 is a schematic side view of a longitudinal position adjusting mechanism according to still another preferred embodiment of the present invention; FIG. 17 is a schematic side view of the vicinity of a frame supporting auxiliary seedling frames according to still another preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is a schematic left side view of a work vehicle 1 according to a preferred embodiment of the present invention, and FIG. 2 is a schematic plan view of the work vehicle 1 shown in FIG.

In this specification, as indicated by an arrow in FIG. 1 or 2, the side in which the work vehicle 1 travels is defined as the front side, and unless otherwise specified, the left side in the direction of movement of the work vehicle 1 is defined as " The left side is called the left side, and the opposite side is called the right side.

A working vehicle 1 according to this embodiment is a rice transplanter for planting rice seedlings in a field. As shown in FIGS. 2, a fertilizing device 26 that supplies fertilizer to the field, and a line that serves as a guideline for the traveling position when traveling while planting seedlings. on the field, an auxiliary seedling frame 74 provided in the front part of the traveling vehicle 2 to accommodate the seedlings supplied to the seedling planting part 63, and in the front part of the traveling vehicle 2 It is provided with a GNSS receiver 130 (an example of the "position information acquiring means" according to the present invention) and an orientation sensor 80 that detects the orientation of the traveling vehicle 2 .

As shown in FIG. 1, the traveling vehicle 2 includes a controller 87 (corresponding to the “control means” according to the present invention) covered with a front cover 47, and a main frame 3 arranged substantially in the center of the traveling vehicle 2. , a rear frame 6 attached to the rear end of the main frame 3 and extending in the width direction of the work vehicle 1, a floor step 60 arranged above the main frame 3, and a cockpit provided above the floor step 60. 48, a control section 49, an engine 7 provided below the cockpit 48, a pair of left and right front wheels 8 (steering wheels) and a pair of left and right rear wheels 9 as running wheels, and the power of the engine 7 A transmission mechanism such as a transmission case 30 for transmitting power to the front wheels 8 and the rear wheels 9 is provided.

As shown in FIG. 2, the control unit 49 includes a forward/reverse lever 35 for changing the forward/rearward movement of the traveling vehicle 2 and the vehicle speed, a steering mechanism 43 including a steering wheel 56 for steering the pair of left and right front wheels 8, and a steering wheel. 56, a monitor 61 (see FIG. 8) having operation switches, and an operation unit 54 having various operation switches for operating the work vehicle 1. . In this embodiment, based on the output signal of the controller 87, the steering wheel 56 is automatically driven to drive the steering wheel 56 so that the work vehicle 1 travels straight on the field. It is configured to be able to execute turning control for automatically driving the steering wheel 56 so as to turn upward.

The straight-travel assist lever 79 is swung when acquiring the position information of the traveling vehicle 2 and when starting or stopping the straight-travel control.

The steering mechanism 43 includes a steering wheel 56, a steering shaft 83, a pitman arm and tie rods (not shown).

On the other hand, the driving force output from the engine 7 is transmitted through a belt-type power transmission mechanism 4 and a hydrostatic continuously variable transmission (HST) 25 provided below the floor step 60, as shown in FIG. It is transmitted to the mission case 30.

The hydrostatic continuously variable transmission 25 has a trunnion shaft (not shown), and when the forward/reverse lever 35 is operated, the opening of the trunnion shaft is adjusted by driving the HST servomotor 150 (see FIG. 3). , the output to the mission case 30 is changed.

The power transmitted to the transmission case 30 is changed in its interior to provide driving power to the pair of left and right front wheels 8 and the pair of left and right rear wheels 9, and power for driving the seedling planting section 63 (driving power). power) is transmitted separately.

Driving power is transmitted to the pair of left and right front wheels 8 via the front wheel final case 13 and the front wheel axle 31 (see FIG. 1), and also to the pair of left and right rear wheel transmission shafts 14 shown in FIGS. , to the pair of left and right rear wheels 9 via a pair of left and right rear wheel gear cases 51 and axles 82 (see FIG. 1).

On the other hand, the drive power is transmitted to a planting clutch (not shown) provided at the rear of the traveling vehicle 2, and further transmitted to the seedling planting section 63 when the planting clutch is engaged.

The seedling planting part 63 is attached to the traveling vehicle 2 via the lifting link device 5, as shown in FIG. The lifting link device 5 includes an upper link arm 85 and a pair of left and right lower link arms 86, and is configured to move the seedling planting section 63 up and down.

The front ends of the upper link arm 85 and the lower link arm 86 are attached to the link base frame 10 fixed to the rear frame 6, and the other ends are attached to the upper and lower link arms 11 positioned below the seedling planting section 63. It is

Here, when the electrohydraulic valve 88 (see FIG. 3) is controlled by the controller 87 to hydraulically compress the elevating hydraulic cylinder 12 shown in FIG. The attaching portion 63 is configured to be raised to the non-working position. When the seedling planting section 63 is in the non-working position, its lower end is located at substantially the same height as the bottom of the main frame 3 .

On the other hand, when the elevating hydraulic cylinder 12 is hydraulically extended, the upper link arm 85 is rotated downward, and the seedling planting section 63 is moved to the working position (shown in FIG. 1) where the seedling planting work can be performed. position).

As shown in FIGS. 1 and 2, the seedling planting unit 63 includes a table 65 on which a mat-shaped seedling with soil (hereinafter referred to as a "seedling mat") is leaned, and is provided behind and below the table 65. 2), a center float 38 provided at the bottom of the seedling planting section 63, and four side floats 39 arranged on the left and right sides of the center float 38.

As shown in FIG. 2, the four planting devices 64 are arranged side by side in the width direction of the work vehicle 1, and each planting device 64 has two pairs of left and right planting tools 69 arranged in the front-rear direction. When the planting clutch is engaged and the drive shaft 67 shown in FIG. 1 is rotated, the front planter 69 and the rear planter 69 shown in FIGS. The seedlings positioned at the lower end of the platform 65 are alternately taken out and planted in the field while rotating freely. Thus, in this embodiment, since a total of eight planting tools 69 are arranged side by side in the left-right direction, when the working vehicle 1 travels straight while planting seedlings in the field, eight rows of seedlings are formed. be done.

The center float 38 and the four side floats 39 are configured to slide and level the field as the working vehicle 1 travels, and the field leveled by the floats 38 and 39 is lined with each plant. Seedlings are planted by the attachment device 64 . The center float 38 and the four side floats 39 are respectively swung according to unevenness of the field.

A pair of left and right drawing markers 40 are respectively a drawing body 41 that rolls on the field to form a line when the traveling vehicle 2 travels, and a substantially L-shaped marker that connects the drawing body 41 and the traveling vehicle 2. Equipped with a rod 42 (see also FIG. 9), it is configured to be switchable between an action posture in which the wire drawing body 41 contacts the field and a non-action posture in which the wire drawing body 41 does not contact the field.

When planting seedlings while the work vehicle 1 is traveling straight on the field, the line-drawing marker 40 of the pair of left and right line-drawing markers 40 for planting the seedlings next (after turning) is in the working posture. By running straight in this state, a line is formed on the field as a guideline for the running position when running straight after turning. 1 and 2 show the left delineating marker 40 in the active position and the right delineating marker 40 in the non-active position.

As shown in FIGS. 1 and 2, a center mascot 18 is provided at the front and widthwise central portion of the traveling vehicle 2, and the work vehicle 1 turns over the field and advances straight on the next row. Seedlings can be planted at an appropriate position by traveling straight while operating a steering wheel 56 so that the center mascot 18 passes on the line formed by the drawing marker 40 when traveling. That is, eight rows of seedlings (after turning) can be planted at appropriate intervals with respect to eight rows (eight rows) of seedlings planted before the work vehicle 1 turns.

The auxiliary seedling frame 74 is attached to the front part of the traveling vehicle 2 via a frame 77 that supports the auxiliary seedling frame 74, as shown in FIGS. It is

3 is a block diagram of the control system, detection system, input system and drive system of the work vehicle 1 shown in FIG. 1, and FIG. 4 is a partial enlarged view of the forward/reverse lever 35 shown in FIG. be.

As shown in FIG. 3, the control system of the work vehicle 1 includes a controller 87 that controls the overall operation of the work vehicle 1 and a timer 105 that measures time.

The controller 87 includes a processing unit 89 having a CPU (Central Processing Unit) and a storage unit 93 having a ROM (Read Only Memory) and a RAM (Random Access Memory). Various programs and data are stored.

As shown in FIG. 3, the detection system of the work vehicle 1 includes a steering sensor 58 having an encoder (not shown) for detecting the steering angle (angle from the neutral position) of the steering wheel 56, and a steering shaft 83 (see FIG. 3). 1) to detect input torque to the steering wheel 56 (steering amount at that time), an engine rotation sensor 96 to detect the rotation speed of the engine 7, and an upper link for the link base frame 10. A link sensor 90 that detects the relative angle of the arm 85, a GNSS receiver 130 that functions as position information acquisition means and receives radio waves from artificial satellites, and left and right axles 82 connected to a pair of left and right rear wheels 9. a rear wheel rotation sensor 29 that counts the number of revolutions, a float sensor 33 that detects the vertical position of the front part of the center float 38, an orientation sensor 80, and an inclination detection sensor 37 that detects the inclination of the traveling vehicle 2 in the roll direction. I have.

The float sensor 33 is configured to detect the vertical position of the front portion of the center float 38 and output to the controller 87 when the front portion of the center float 38 is swung according to the unevenness of the field.

As shown in FIG. 3, the input system of the work vehicle 1 detects the operation position of a forward/reverse lever 35 (see FIGS. 1, 2, and 4) that changes the forward/rearward movement of the work vehicle 1 and the vehicle speed. A lever sensor 36 and a straight-travel assist lever 79 (see FIGS. 1 and 2) which is pivotally operated in one direction when acquiring position information of the traveling vehicle 2 and when straight-travel control is started or stopped. A straight advance assist lever sensor 81 that detects the operation, a finger lever sensor 16 that detects the swinging operation of the finger lever 23 that raises and lowers the seedling planting part 63, and a planting sensor that switches on and off the seedling planting work. It is provided with an on/off switch 19, a monitor 61 shown in FIG. 8, a marker switch 28 for switching the orientation of each of the left and right line drawing markers 40, and a turning control switch 17 for setting turning control. The turning control switch 17 is provided on the operating portion 54 .

In this embodiment, the straight advance assist lever 79 can be swung upward and downward, and after being swung in either direction, it is automatically returned to its original vertical position by a spring. It is configured.

The finger lever 23 and the planting ON/OFF switch 19 are provided on the forward/reverse lever 35 as shown in FIG.

As shown in FIG. 3, the drive system of the work vehicle 1 includes a throttle motor 97 that adjusts the amount of air intake of the engine 7 provided below the operator's seat 48, and when the seedling planting section 35 is raised and lowered, An electro-hydraulic valve 88 for expanding and contracting the lifting hydraulic cylinder 12, an HST servomotor 150 for adjusting the opening of the trunnion shaft in the hydrostatic continuously variable transmission 25 to change the forward and backward movement of the work vehicle 1 and the vehicle speed, and steering. A left and right pair of a steering motor 57 that rotates the shaft 83 and the steering wheel 56, an electromagnetic valve 103 that turns on and off the side clutch of the rear wheel 9, a power steering 108, and a planted clutch motor 27 that operates the planted clutch. A marker motor 34 for swinging each drawing marker 40 is provided.

In this embodiment, when the steering angle of the steering wheel 56 becomes equal to or greater than a predetermined steering angle threshold while the traveling vehicle 2 is traveling (in other words, when the steering wheel 56 is turned largely), Since the controller 87 recognizes that the traveling vehicle 2 is turning, it is configured to drive the planted clutch motor 27 and switch to a state in which power is not transmitted to the rear wheel 9 on the inner side of the turn. By configuring in this way, it is possible to smoothly turn the headland portion of the field.

The controller 87 is also configured to be able to calculate the current height (vertical position) of the seedling planting section 35 based on the output signal from the link sensor 90 .

In addition, when the work vehicle 1 is planting seedlings and traveling on the field, the controller 87 controls the electro-hydraulic valve 88 based on the detection signal from the float sensor 33 to perform the operation shown in FIG. By extending and retracting the lifting hydraulic cylinder 12 to raise and lower the seedling planting section 63 shown in FIG. 1, the planting depth of the seedlings in the field can be kept constant.

The work vehicle 1 configured as described above can plant seedlings in a field while alternately performing straight-ahead control and turning control when traveling on the field in the following manner.

FIG. 5 is a schematic plan view showing a route along which the work vehicle 1 shown in FIG. 1 travels while planting seedlings in a field.

As shown in FIG. 5, a farm field 200 in which the work vehicle 1 plants seedlings has a substantially rectangular shape in plan view, with two sides 201 and 203 extending in the north-south direction and two sides 202 and 204 extending in the east-west direction. , four peripheral areas 211 to 214 extending along each side 201 to 204, and a central area 210 surrounded by the four peripheral areas 211 to 214. FIG. The four peripheral regions 211 to 214 are so-called headlands, and the width of each of the peripheral regions 211 and 213 in the north-south direction and the width of each of the peripheral regions 212 and 214 in the east-west direction are equal to the width of the seedling planting of the working vehicle 1. The width is greater than the working width (width for eight seedlings) by the unit 63 .

When seedlings are planted in the field 200, the controller 87 alternately performs straight-ahead control and turning control to run the field 200 in a zigzag pattern. Seedlings are planted sequentially in the four peripheral areas 211 to 214, as indicated by the thick gray lines. In this embodiment, in order for the controller 87 to perform swing control, the swing control switch 17 must be operated in advance to set a state in which swing control is performed.

When seedlings are planted in the central region 210, first, positional information of the start point and end point of the reference line used for straight control is obtained by so-called teaching. In the straight-ahead control, the steering wheel 56 is driven so that the work vehicle 1 runs straight parallel to a virtual reference line connecting the start point and the end point.

In acquiring the positional information of the starting point of the reference line, the work vehicle 1 is moved to the north side of the peripheral area 212 of the farm field 200 shown in FIG. , and the straight-travel assist lever 79 is swung downward, so that the GNSS receiver 130 is used to acquire the position information of the starting point 218 of the reference line.

Next, the marker switch 28 is operated, and with the east side drawing marker 40 (turning side, in this case, the left side drawing marker 40) switched to the active posture, based on the operator's operation, the arrow is drawn. , the work vehicle 1 is moved to a location on the south side of the peripheral edge region 212, and the straight advance assist lever 79 is operated to swing downward. As a result, the GNSS receiver 130 is used to obtain the position information of the endpoint 219 of the baseline. The positional information of the start point and end point of the reference line acquired as described above is stored in the storage unit 93 . In this embodiment, when the marker switch 28 is operated and the line drawing marker 40 is switched to the active posture, the work vehicle 1 is controlled based on the output signal of the steering sensor 58 every time the work vehicle 1 turns. When turning is detected, one of the drawing markers 40 in the active posture is automatically switched to the non-working posture, and after the work vehicle 1 turns, the other drawing marker 40 is automatically switched to the active posture. is configured to

Further, in this embodiment, both when the steering wheel 56 is turned by the operator and when the steering wheel 56 is turned based on the output signal of the controller 87 (straight ahead control, turning control). Although the vehicle speed is set based on the operating position of the forward/reverse lever 35, the vehicle speed is regulated at any time below a predetermined speed while turning control is being performed.

When the positional information of the start point and the end point of the reference line is acquired, the work vehicle 1 is turned to the east side based on the operation of the operator, to the planting start position 207 (x mark) of the first row in the central area 210. In the row that has been moved and is shown as "1st row" in FIG.

Specifically, after the finger lever 23 shown in FIG. 4 is operated to swing downward and the seedling planting section 63 is switched to the working position, the planting ON/OFF switch 19 is pressed to operate each The planting device 64 is driven, and planting of seedlings by eight rows of planting tools 69 (see FIG. 2) is started. At this time, as shown in FIG. 5, the right drawing marker 40 is automatically switched to the active position.

Next, the operator swings the straight advance assist lever 79 upward, and the straight advance control by the controller 87 is started. The conditions for starting straight-ahead control are the target line (a virtual line pointing to the position to be traveled, a line parallel to the reference line) when traveling straight on each row, and the direction of the traveling vehicle 2 (the direction of the aircraft 2). direction) is less than 30°, the straight assist lever 79 is operated to swing upward.

In straight control, the controller 87 controls the detection output from the GNSS receiver 130 and the direction sensor 80 so that the work vehicle 1 runs straight parallel to the reference line 208 indicated by the dashed line with an arrow in FIG. Based on the signal, a steering motor 57 is driven to steer a pair of left and right front wheels 8 as steering wheels. As a result, work vehicle 1 travels straight north in the row indicated as "first row".

In the straight-ahead control according to this embodiment, the controller 87 moves 240 cm toward the next work row (east side) from the reference line 208 (30 cm between the rows) when traveling in the "first row" of the central region 210. After setting a virtual target line extending parallel to the reference line 208 at a position shifted by 8 rows of seedlings, the steering motor 57 is driven along the target line. Also, when traveling in the "nth row" (n is an integer of 2 or more), the controller 87 sets the reference line to a position shifted by 240 cm toward the next working row (east side) from the n-1th row line. After setting a target line extending parallel to 208, the steering motor 57 is driven along the target line.

However, in straight control, it is not always necessary to drive the steering motor 57 so that the machine body 2 runs along the generated target line. The steering motor 57 is driven so that the azimuth deviation between the azimuth of the airframe 2 and the target azimuth becomes small from the point where the straight advance assist lever 79 is swung upward in each of the 1st to nth rows as the target azimuth. It may be configured as

When the work vehicle 1 approaches the peripheral area 213, the operator swings the straight-travel assist lever 79 upward, and the straight-travel control by the controller 87 ends.

When the straight-ahead control is finished in this manner, the operator swings upward the finger lever 23 shown in FIG. 4 to raise the seedling planting portion 63 .

In the work vehicle 1 according to this embodiment, the forward/reverse lever 35 is in the forward position (the position in which the vehicle moves forward) in a state where the swing control is performed by operating the swing control switch 17, and When the finger lever 23 is swung upward, the controller 87 starts turning control. A detailed description of the turning control will be given below.

FIG. 6 is a flowchart showing the turning control procedure by the controller 87 of the work vehicle 1 shown in FIG. 1, and FIG. 7 shows the steps shown in FIG. It is a schematic plan view showing the relationship between. In FIG. 7, the one-dot chain line with an arrow (during straight running) and the two-dot chain line with an arrow (during turning) represent the trajectory along which the central portion of the work vehicle 1 moves in the width direction (horizontal direction). there is Also, in FIG. 7, the portion related to step s10 shown in FIG. 6 is shown in gray for convenience.

In turning control, the controller 87 first acquires data on the distance to the turning target position from the storage unit 93 (step s1).
Here, the target of the turning control is to turn the work vehicle 1 to a position in the east-west direction where it travels straight after turning. The position is the "second row" position (position in the east-west direction) shown in FIG. That is, the distance to the turning target position is, in layman's terms, the distance in the east-west direction between the "first row" and the "second row" shown in FIG. Since the attaching part 63 is configured as an 8-row rice transplanter having 8 rows of planting tools 69 in the horizontal direction, data of a value of 240 cm (30 cm between plants×8 rows) is stored.

Thus, when the data of the distance to the turning target position is acquired, the controller 87 drives the HST servo motor 150 to regulate the vehicle speed to 0.75 m/s, and drives the steering motor 57 to set the predetermined steering angle θd. [deg], the steering wheel 36 is rotated in the direction of the next working row (to the right when turning to the "second row") (step s2). In this specification, units are shown in [ ].

Here, the predetermined steering angle θd [deg] is the steering angle that is the same as the steering angle of the steering wheel when turning control is performed in the conventional eight-row seedling transplanter. is an angle exceeding 100° from the rudder angle at which the When the field conditions are good and the running wheels 8 and 9 are less likely to slip, the steering wheel 36 is automatically held at a predetermined steering angle θd, and the fuselage 2 turns. By automatically returning the rudder angle of the steering wheel 36 to the neutral position just before the direction (azimuth) changes by 180°, the fuselage 2 is oriented substantially southward, as shown in FIG. , the vehicle 1 can be positioned at the position of the second row (position in the east-west direction), which is the next working row (row).

However, in the conventional 8-row seedling transplanter, when turning control is performed, the driving force is weakened due to the slipping of the traveling wheels 8, 9, and the traveling vehicle 2 hardly moves forward, and the vehicle 2 can be moved on the spot. If the steering wheel is held at a predetermined steering angle θd until the traveling vehicle 2 rotates 180° in the yaw direction, the turn will be too small. As indicated by the thin gray line with an arrow in FIG. The work vehicle 1 cannot be positioned at the position in the east-west direction), and after turning, the vehicle 1 may be positioned at a position shifted westward from the position of the "second row" in the east-west direction. there were.

On the other hand, in this embodiment, the controller 87 rotates the steering wheel 36 to the predetermined steering angle θd, and then changes the slippage of the traveling wheels 8 and 9 from the angular velocity of the traveling vehicle 2 in the following manner. Further, the angle difference between the azimuth of the traveling vehicle 2 and the target line of the "first row" (a line parallel to the reference line and located 240 cm east of the reference line) is 30. ° or more, the steering wheel 36 is automatically turned back to the rudder angle θdi with the amount of slip taken into consideration. The work vehicle 1 can be moved to the position of the "second row" when turning after running straight on the "first row". In the following description, the control of automatically turning the steering wheel 56 back to the rudder angle θdi in which the slip amount of the running wheels 8 and 9 is taken into account when turning control is being performed is referred to as "return control".

When the steering wheel 36 is rotated to a predetermined steering angle .theta.d, the controller 87 causes the traveling vehicle 2 to turn to the position of the next target line "second row" if the traveling wheels 8 and 9 do not slip. The ideal angular velocity .omega.i is calculated by the following equation (1) (step s3).
ωi=0.071vθa[deg/sec]. . . (1)

In equation (1), v is the actual vehicle speed [m/s] of the traveling vehicle 2 obtained by the GNSS receiver 130 and θa is the steering angle of the steering wheel 56 obtained by the steering sensor 58 . Further, "0.071" is a parameter for determining the slip of the work vehicle 1 according to this embodiment, and the tread width of the running wheels and the wheel base (the longitudinal direction between the front wheel axle 31 and the rear wheel axle 82) Since the ideal angular velocity during a turn differs depending on the distance of ), it is adjusted by multiplying parameters with different values for each work vehicle having a different tread width and wheel base.

In this embodiment, when the vehicle speed v is 0.1 [m/s] or less, the controller 87 determines that the work vehicle 1 is stopped and sets ωi=0. there is Also, the value of ωi continues to be updated moment by moment until the switchback control ends.

Next, the controller 87 calculates the actual angular velocity ωp of the traveling vehicle 2 in the yaw direction from the detection signal of the orientation (direction of the airframe 2) θp of the traveling vehicle 2 output from the orientation sensor 80 by the following equation (2). (step s4). In the following description, "·" is a multiplication symbol.
ωp=10·{θp−θ(p−1)}[deg/sec] . . . (2)

In this embodiment, the output frequency of the detection signal of the direction sensor 80 is every 0.1 seconds (data period is 0.1 second), and from the direction θp of the traveling vehicle 2 obtained from the direction sensor 80, one data By multiplying the value obtained by subtracting the azimuth θ(p−1) of the preceding traveling vehicle 2 by 10, the actual angular velocity ωp of the traveling vehicle 2 in the yaw direction for each second can be calculated. In addition, in this embodiment, the formula (2) is calculated using a 0.5-second moving average. Also, the value of ωp continues to be updated from time to time thereafter.

When the ideal angular velocity ωi and the actual angular velocity ωp of the traveling vehicle 2 in the yaw direction are thus calculated, the controller 87 calculates the angle between the azimuth of the body 2 determined by the detection signal output from the azimuth sensor 80 and the target line. It is determined whether or not the difference is 30° or more (step s5).

As a result of the determination, if the angular difference between the azimuth of the airframe 2 and the target line is not 30° or more, the determination is repeated until the angular difference becomes 30° or more.

On the other hand, if the angle difference between the azimuth of the airframe 2 and the target line is 30° or more as a result of the determination, the controller 87 drives the steering motor 57 so that the steering angle of the steering wheel 56 becomes The steering wheel 56 is turned back so that θdi [deg] calculated by the equation (3) is obtained (step s6, see FIGS. 6 and 7).
.theta.di=.theta.d-(.omega.p-.omega.i).sin .theta.p.cos(.theta.p/2).(10+x)[deg] . . . Formula (3)

However, θdi is in the range of θd−100≦θdi≦θd, and the steering is returned in the steering-back direction (toward the neutral position) from the steering angle θd within a range with an upper limit of 100°.

In equation (3), θd [deg] is the same as the rudder angle of steering wheel 36 when turning control is performed in a conventional seedling transplanter for eight-row planting, as in step s2. In layman's terms, the steering wheel 56 is turned back from the steering angle θd toward the neutral position by "(ωp−ωi)·sin θp·cos(θp/2)·(10+x)" [deg]. That is, "(ωp−ωi)·sin θp·cos(θp/2)·(10+x)" [deg] is the steering-back control amount (control amount of the steering motor 57). Also, x is a control value which will be described in detail later.

θp indicates the direction of the traveling vehicle 2 (orientation of the airframe 2) as described above, and "sin θp·cos (θp/2)" takes a value of 0 to approximately 0.77. Since it is desired to change the control amount depending on the direction of the body 2 (the traveling vehicle 2), "sin θp·cos (θp/2)" is multiplied.

On the other hand, the value calculated by "ωp-ωi" ([deg/sec]) is a correlation value representing the slip amount (degree of slip) of the running wheels 8,9.

Here, when the working vehicle 1 (the traveling vehicle 2) turns, the traveling wheels 8 and 9 may slip depending on the state of the field, and the traveling vehicle 2 may turn on the spot without moving forward. In this case, the actual angular velocity ωp of the traveling vehicle 2 in the yaw direction becomes higher and the value calculated by ωp−ωi also becomes larger than when the vehicle 2 turns normally with little slip. That is, there is a correlation between the slip amount of the running wheels 8 and 9 and the value calculated by ωp-ωi. Therefore, by subtracting the ideal angular velocity ωi from the actual angular velocity ωp of the traveling vehicle 2 in the yaw direction, it is possible to calculate the correlation value representing the slip amount (degree of slip).

Therefore, for example, it is possible to determine that the running wheels 8 and 9 are slipping when the value of ωp-ωi is equal to or greater than a predetermined value. In an actual farm field, ωp-ωi takes a value of about 0 to 5, and is about 10 at maximum.

As described above, in this embodiment, the steering wheel 56 is turned back to the steering angle θdi that takes into account the slip amount calculated by ωp-ωi (in other words, according to the slip amount) (that is, the steering wheel 56 is turned back to the steering angle θdi). is performed), it is possible to prevent the running wheels 8 and 9 from slipping and making an excessively small turn.

Furthermore, in this embodiment, the control value x in the formula (3) is arbitrarily set on the monitor 61 in advance, so that the amount (angle, amount of rotation) can be adjusted.

FIG. 8 is a drawing showing a setting screen for the control value x displayed on the monitor 61 when turning control is performed. FIG. FIG. 8B is a drawing showing a setting screen of the control value x in the steering back control when turning to the right.

The monitor 61 has a display 32 for displaying the currently set control value x and an operation switch 62 for setting the control value.

In this embodiment, the operation switch 62 is used to select any number from a total of 21 integer numbers from -10 to 10 including 0 as the numerical value of the control value x to be substituted into the equation (3). The set numerical value is stored in the storage unit 93, read out from the storage unit 93 at step s6 shown in FIG. 6, and the steering angle θdi [deg] is calculated. .

The larger the value of the control value x set within the range of -10 to 10, the more the steering angle is returned from the steering angle θd ((ωp−ωi)·sinθp·cos(θp/2)·(10+x)). The value of [deg] increases, and the turning of the work vehicle 1 becomes large. As a result, in the travel route shown in FIG. 5, the work vehicle 1 is positioned further east after the turn.

Therefore, the operator compares the east-west position of the work vehicle 1 after turning by the turning control with the east-west position of the next straight traveling line formed by the delineation marker 40, and performs the work after turning. When the vehicle 1 is located on the west side of the position of the next row in which the vehicle 1 should travel straight ahead, the operation switch 62 of the monitor 61 is used to set the control value x to a larger value, thereby increasing the control value x. The position of the work vehicle 1 can be shifted further to the east side, and the position in the east-west direction can be aligned with the next line to travel straight ahead.

Also, the smaller the value of the control value x set within the range of -10 to 10, the more the angle (ωp−ωi)·sin θp·cos (θp/2)·(10+x )” [deg] becomes smaller, and the turn of the work vehicle 1 becomes smaller. As a result, in the travel route shown in FIG. 5, the work vehicle 1 is positioned further west after the turn.

Therefore, the operator compares the east-west position of the work vehicle 1 after turning by the turning control with the east-west position of the next straight traveling line formed by the delineation marker 40, and performs the work after turning. When the vehicle 1 is located on the east side of the position of the next row to travel straight ahead, the operation switch 62 of the monitor 61 is used to set the control value x to a smaller value, thereby reducing the By shifting the position of the working vehicle 1 further westward, it is possible to align the position in the east-west direction with the next line to travel straight ahead.

In this embodiment, as shown in FIGS. 8(a) and 8(b), the control value x in the steering back control performed when turning left and the control value x when turning right are performed. The control value x in the switchback control can be set independently of each other. In other words, the control value x used in the steering-back control can be set to different values depending on whether the vehicle is turning to the left under turning control or turning to the right under turning control.

Therefore, in the field 200 and the travel route shown in FIG. Also, by setting the control value x suitable for each headland, it is possible to determine the east-west position of the next line traveling straight ahead and the position of the work vehicle after turning in either the north headland or the south headland. 1 (running vehicle 2) in the east-west direction, it is possible to smoothly shift to straight-ahead control after turning.

As can be seen from equation (3), when a value of "-10" is set as the control value x, the portion of "(10+x)" becomes 0 and θdi = θd [deg]. Therefore, the steering back control from the steering angle θd is not performed. That is, in this case, the body 2 is turned at the same steering angle as that of the conventional eight-row seedling transplanter.

Further, as can be seen from the expression (3), when the value of "10" is set as the control value x, the portion of "(10+x)" becomes 20, and the value of "0" as the control value x. is set back over twice the angle.

On the other hand, when the steering wheel 56 is rotated to the steering angle of θdi, the controller 87 detects the angle difference between the direction of the airframe 2 determined by the detection signal output from the direction sensor 80 and the target line for the next straight travel. is 60° or less (step s7).

As a result of the determination, if the angle difference between the azimuth of the airframe 2 and the target line exceeds 60°, the controller 87 holds the steering angle of the steering wheel 56 at θdi until the angle difference becomes 60° or less. do.

On the other hand, as a result of the determination, if the angle difference between the azimuth of the airframe 2 and the target line is 60° or less, the controller 87 ends the steering back control, drives the steering motor 57, and performs steering. The steering angle of the wheel 56 is changed to .theta.d (step s8, see FIGS. 6 and 7).

As described above, the steering angle of the steering wheel 56 is held at θdi [deg] while the steering return control is being performed. Since the azimuth and angular velocity of the aircraft 2 change from moment to moment, the values of ωp (actual angular velocity of the aircraft), ωi (ideal angular velocity), and θp (azimuth of the aircraft) in Equation (3) are also updated from moment to moment. be. Therefore, the steering angle θdi [deg] of the steering wheel 56 during the return control is also continuously changed (updated) until the angle difference between the azimuth of the airframe 2 and the target line becomes 60° or less (step s8).

When the steering angle of the steering wheel 56 is changed to θd in this way, the controller 87 controls the angle difference between the azimuth of the airframe 2 determined by the detection signal output from the azimuth sensor 80 and the target line in the next straight run. It is determined whether or not the angle is 50° or less (step s9).

As a result of the determination, if the angle difference between the azimuth of the body 2 and the target line for the next straight run exceeds 50°, the determination is repeated until the angle difference becomes 50° or less.

On the other hand, if the angle difference between the azimuth of the machine body 2 and the target line for the next straight travel is 50° or less as a result of determination, the controller 87 drives the HST servo motor 150 to reduce the vehicle speed to zero. .5 m/s (step s10, see FIGS. 6 and 7).

When the vehicle speed of the work vehicle 1 is regulated to 0.5 m/s, the controller 87 calculates the azimuth of the machine body 2 at which the steering wheel 56 starts to return to the neutral position according to the following equation (4) (step s11).
θst=1.2·ωp[deg] . . . Formula (4)

Next, the controller 87 determines whether or not the angle difference between the direction of the machine body 2 determined by the detection signal output from the direction sensor 80 and the target line for the next straight run is equal to or less than the calculated angle θst. (step s12).

As a result of the determination, if the angle difference between the azimuth of the aircraft 2 and the target line for the next straight run exceeds θst [deg], the angle difference is The determination is repeated until θst [deg] or less.

On the other hand, if the angle difference between the azimuth of the machine body 2 and the target line for the next straight travel is θst [deg] or less as a result of the determination, the controller 87 drives the steering motor 57 to turn the steering wheel 56 is returned to the neutral position (step s13). As a result, after turning, the azimuth of the machine body 2 is constant (towards south or north in the case of the agricultural field 200 and travel route shown in FIG. 5).

Finally, the controller 87 releases the vehicle speed regulation, drives the HST servomotor 150, and changes the vehicle speed according to the operating position of the forward/reverse lever 35 (step s14).

As described above, in the turning control according to the present embodiment, the steering wheel 56 is turned back to the steering angle θdi that takes into account the slip amount calculated by ωp−ωi. Therefore, it is possible to prevent the running wheels 8 and 9 from slipping and making an excessively small turn.

Furthermore, as a result of turning control executed by operating the turning control switch 17, the position in the east-west direction (the position of the line formed by the drawing marker 40 and also the target line) where the work vehicle 1 travels straight next. 8, the operator operates the operation switch 62 shown in FIG. 8 to change the value substituted for the control value x in equation (3). By doing so, the position in the east-west direction of the work vehicle 1 (traveling vehicle 2) after turning can be adjusted.

When the turning control is finished in this way, in this embodiment, the controller 87 automatically lowers the seedling planting section 63 to the working position, starts planting seedlings, and straight-ahead assist lever 79 for starting straight-ahead control. is configured to automatically shift to straight-ahead control (start straight-ahead control) without being operated.

As a result, the work vehicle 1 traveled southward at the position shown as "second row" in FIG. At appropriate intervals, seedlings can be planted on its east side.

When the work vehicle 1 approaches the peripheral area 211 under straight-ahead control, the operator swings the straight-ahead assist lever 79 upward, and the straight-ahead control by the controller 87 is terminated.

Next, the operator swings upward the finger lever 23 shown in FIG. 4 to raise the seedling planting portion 63 and turn it from the "first row" to the "second row." Similarly, turning from the “second row” to the “third row” is performed by turning control.

Thereafter, in the same way, the work vehicle 1 repeats straight traveling accompanied by planting seedlings (indicated by the dashed line in FIG. 5) and turning by turning control (indicated by the dashed line in FIG. 5) while repeating "n Run to the position of "row".

After planting the seedlings in the entire central area 210 in this way, the work vehicle 1 plants the seedlings while traveling through the peripheral areas 211 to 214 based on the operation by the operator. As a result, seedlings are planted all over the field 200 .

The method of planting seedlings in a field while alternately performing straight-ahead control and turning control has been described in detail above. , the angle of the line marker 40 in the active posture can be automatically adjusted according to the depth of the field or the inclination of the machine body as follows when traveling straight ahead.

FIG. 9 is a schematic front view showing how the angle of the line marker 40 according to the embodiment shown in FIG. 1 is adjusted according to the depth of the field or the tilt of the machine.

Specifically, FIGS. 9(a) to 9(c) are schematic front views showing a state in which the angle of the line marker 40 is adjusted according to the depth of the field, and FIGS. 9(d) to 9(d). (f) is a schematic front view showing a state in which the angle of the line marker 40 is adjusted according to the inclination of the airframe 2. FIG.

9(a) to 9(c) show a state in which the machine body 2 is substantially horizontal, and FIGS. case is shown.

First, with reference to FIGS. 9(a) to 9(c), the control for automatically adjusting the angle of the right delineation marker 40 according to the depth of the field will be described below.

As shown in FIG. 9(b), the drawing marker 40 moves from the non-action posture in which the drawing body 41 does not contact the field, and the drawing body 41 is brought into contact with the field by driving the marker motor 34 (see FIG. 3). By running the machine body 2 in the state of being switched to the posture, it is possible to form a line on the field that serves as a guideline for the running position during straight running after turning.

However, when the depth of the field is too shallow (in other words, when the field is too hard), the running wheels 8 and 9 do not sink into the field so much that the drawing body 41 of the marking marker 40 does not touch the field surface. There were times when it was not possible to form a line without grounding.

Furthermore, when the field is too deep (in other words, when the field is too soft), the running wheels 8 and 9 sink deeply into the field, so that the drawing body 41 of the marking marker 40 is excessively deep in the field. When the machine body 2 travels in such a state that it bites in too much, an excessive load may be applied to the marker rod 42 .

In light of this situation, in this embodiment, the controller 87 drives the marker motor 34 according to the calculated height position of the seedling planting section 35 based on the output signal from the link sensor 90, It is configured to automatically adjust the angle of the draw marker 40 in the active position.

Specifically, when the calculated height position of the seedling planting portion 35 is lower than the first predetermined height, which is the lower limit height at which a line can be formed in the field, , the running wheels 8 and 9 are not so much sunk in the field, and the drawing body 41 of the right drawing marker 40 in the working posture is not in contact with the surface of the field, so the controller 87 The marker motor 34 is driven by a control amount corresponding to the height of the seedling planting section 35 (the depth of the field), and the right drawing marker 40 in the working posture is rotated downward. . As a result, the marker rod 42 of the right drawing marker 40 is slanted downward to the right, and the drawing body 41 touches the surface of the field, so that a line can be formed in the field.

On the other hand, when the calculated height position of the seedling planting portion 35 is equal to or higher than the second predetermined height higher than the first predetermined height, the height position is shown in FIG. 9(a). Thus, the running wheels 8 and 9 are deeply sunk in the field, and it is recognized that an excessive load is applied to the marker rod 42 of the right drawing marker 40 in the working posture. The marker motor 34 is driven by a control amount corresponding to the height of the field 35 (the depth of the field), and the right marking marker 40 in the active posture is rotated upward. As a result, the marker rod 42 of the right drawing marker 40 is slanted upward to the right, and the drawing body 41 is positioned higher than before the rotation, so that the load applied to the marker rod 42 can be reduced.

The control for automatically adjusting the angle of the right delineation marker 40 according to the depth of the field has been described above with reference to FIGS. 9A to 9C. Similarly, the angle is automatically adjusted by driving the marker motor 34 according to the height position of the seedling planting section 35, that is, the depth of the field.

Next, with reference to FIGS. 9(d) to 9(f), the control for automatically adjusting the angle of the right line marker 40 according to the inclination of the aircraft will be described below.

As shown in FIG. 9(e), when the machine 2 travels in a state in which the machine 2 is substantially horizontal with respect to the surface of the field and at least one of the left and right line markers 40 is in the active posture, the machine 2 runs on the field. In addition, it is possible to form a line that serves as a guideline for the running position during straight running after turning.

However, if the machine body 2 (work vehicle 1) is excessively tilted to the other left or right while one of the left and right drawing markers 40 is in the active posture, the drawing body 41 of the one of the left and right drawing markers 40 will touch the surface. There were times when it was not possible to form a line.

Further, when the machine body 2 (working vehicle 1) is excessively tilted to the left or right while at least one of the left and right line markers 40 is in the active posture, the line drawing body 41 of the one of the left and right line markers 40 may be excessively placed in the field. When the machine body 2 travels in that state, the marker rod 42 may be overloaded.

In light of this situation, in this embodiment, the controller 87 drives the marker motor 34 according to the tilt of the machine body 2 in the roll direction detected by the tilt detection sensor 37, and draws the line-drawing marker in the active posture. It is configured to automatically adjust 40 angles.

Specifically, when the machine body 2 tilts to the left to an angle equal to or greater than the first predetermined angle, which is the limit angle at which a line can be formed in the field, with the right line marker 40 in the working posture. Since it is recognized that the drawing body 41 of the right drawing marker 40 in the working posture is not in contact with the field surface, the controller 87 drives the marker motor 34 with a control amount corresponding to the inclination of the machine body 2. , to rotate downward the right drawing marker 40 in the working posture.

As a result, as shown in FIG. 9(f), the marker rod 42 of the drawing marker 40 on the right side with respect to the machine body 2 is slanted downward to the right with respect to the machine body 2, and the drawing body 41 touches the field surface. , can form a line in the field.

On the other hand, when the fuselage 2 inclines to the right by an angle equal to or greater than the second predetermined angle while the right-hand line marker 40 is in the active posture, the right-hand line marker 40 in the active posture Since it is recognized that an excessive load is applied to the marker rod 42, the controller 87 drives the marker motor 34 with a control amount corresponding to the inclination of the machine body 2, and raises the right drawing marker 40 in the active posture. configured to rotate.

As a result, as shown in FIG. 9(d), the marker rod 42 of the drawing marker 40 on the right side with respect to the body 2 is tilted upward to the right with respect to the body 2, and the drawing body 41 is more inclined than before the rotation. Since it is positioned above, the load applied to the marker rod 42 can be reduced.

The control for automatically adjusting the angle of the right line marker 40 according to the inclination of the body 2 (traveling vehicle 2) has been described above with reference to FIGS. 9(d) to 9(f). Similarly, the angle of the left drawing marker 40 is automatically adjusted by driving the marker motor 34 according to the inclination of the machine body 2 .

As described above, in this embodiment, the angle of the line drawing marker 40 in the working posture is automatically adjusted according to the depth of the field or the inclination of the machine body. The sinking depth of 41 can be kept constant, and a line can be stably formed on the field using a pair of left and right line drawing markers 40 .

According to the present embodiment shown in FIGS. 1 to 9, the yaw angular velocity of the traveling vehicle 2 during turning (specifically, the actual yaw angular velocity ωp of the traveling vehicle 2 during turning and the target From the ideal angular velocity ωi in the yaw direction of the traveling vehicle 2 when turning to the position, the correlation value representing the degree of slip of the traveling wheels 8 and 9 can be calculated (ωp-ωi). Even if the running wheels 2 slip during turning, for example, and the vehicle turns on the spot, the slipping of the running wheels 8 and 9 can be detected with high accuracy.

Furthermore, according to this embodiment, in the turning control, after the steering wheel 56 is turned to the steering angle θd, the calculated correlation value (ωp−ωi) representing the degree of slip of the running wheels 8 and 9 is calculated. The steering wheel 56 is turned back to the neutral position by the angle "(ωp−ωi)·sin θp·cos(θp/2)·(10+x)" [deg]. Due to the slip of 9, the work vehicle 1 can be prevented from making an excessively small turn, and the work vehicle 1 can be turned to an appropriate position.

In addition, since turning can be performed at a steering angle that takes into consideration the slippage of the running wheels 8 and 9, a running route is set during turning, and the steering wheel 56 is frequently rotated along the running route. It is not necessary, and the behavior of the body 2 can be stabilized.

Further, according to this embodiment, by sequentially changing the rudder angle of the steering wheel 56 to θd, θdi, θd, and to the neutral position, the work vehicle 1 can be turned to an appropriate position. Since it is not necessary to separately set a travel route and frequently turn the steering wheel along the travel route, the control can be simplified and the behavior of the machine body (travel vehicle) 2 can be stabilized.

Furthermore, according to this embodiment, in turning control, the amount of rotation when the steering wheel 56 is rotated toward the neutral position (turned back) according to the correlation value representing the degree of slip of the running wheels 8 and 9 By setting the control value x on the monitor 61 as shown in FIG. Since it can be increased or decreased, the position of the work vehicle 1 after turning can be easily adjusted on the monitor 61 .

In addition, according to this embodiment, different control values x can be set on the monitor 61 for turning to the left and for turning to the right. headland) and the other headland (southern headland), the position of the work vehicle 1 after turning can be appropriately adjusted at each headland.

FIG. 10(a) is a schematic side view showing an auxiliary seedling frame of a conventional work vehicle, and FIG. 10(b) is an auxiliary seedling frame 74 on the left side of the work vehicle 1 according to another preferred embodiment of the present invention. is a schematic side view of the vicinity of .

As shown in FIG. 10(a), there is a conventional auxiliary seedling frame which is configured in two stages, upper and lower, in a work vehicle, and which is configured to be able to be rotated and unfolded in the front-rear direction. By unfolding the auxiliary seedling frames arranged vertically in this way, the assistant can easily slide a new seedling box backward from the bank (front of the vehicle) onto each auxiliary seedling frame. can supply.

However, since there is no place on the work vehicle for storing empty seedling boxes, if the empty seedling boxes are returned to the auxiliary seedling frames, it will hinder the supply of new seedling boxes. I had a problem.

In light of this situation, in this embodiment, as shown in FIG. When a new seedling box is supplied to the auxiliary seedling frame 74, the rack 44 is tilted and used as a rail, and the empty seedling box is slid forward and downward. You can send seedling boxes.

FIG. 11 is a schematic side view of the vicinity of the right auxiliary seedling frame 74 according to the embodiment shown in FIG. 10(b), and FIG. FIG. 11(b) is a schematic side view showing a state in which the collection basket is pulled out from the rail, and FIG. 11(b) is a schematic side view showing a state in which the collection basket provided below the right auxiliary seedling frame 74 is accommodated in the rail. It is a side view.

As shown in FIGS. 11(a) and 11(b), the right auxiliary seedling frame 74 is provided with a recovery basket 45 below it for accommodating empty seedling boxes. The collection basket 45 can be slid along a rail 50 fixed to a frame 46 extending downward from the frame 74 and can be pulled out or stored within the rail 50 .

In this embodiment, the frame 77 that supports the right auxiliary seedling frame 74 is rotatable. The car 45 is integrally rotated. Therefore, when an empty seedling box housed in the collection basket 45 is to be collected, the assistant rotates the right auxiliary seedling frame 74 and the collection basket 45 by approximately 180 degrees at the bank, and then the collection basket is opened. An empty seedling box can be retrieved from the vehicle by sliding 45 forward.

On the other hand, FIG. 12 is a schematic side view of the vicinity of the left auxiliary seedling frame 74 according to still another preferred embodiment of the present invention, and FIG. 12(b) is a schematic side view of the vicinity of the unfolded left auxiliary seedling frame 74. FIG.

In this embodiment, a rack 44 for accommodating an empty seedling box is provided above the left and upper auxiliary seedling frame 74 .

As shown in FIG. 12(b), the height of the rack 44 is designed so that tall seedlings do not come into contact with the rack 44 even when seedling boxes are accommodated in the upper auxiliary seedling frame 74. there is

FIG. 13 is a schematic side view of the vicinity of the right auxiliary seedling frame 74 according to the embodiment shown in FIG. 12, and FIG. FIG. 12B is a schematic side view of the vicinity of the unfolded right auxiliary seedling frame 74. FIG.

As shown in FIG. 13, a collection basket mounting frame 52 is fixed to the upper auxiliary seedling frame 74, and a collection basket 45 for accommodating empty seedling boxes can be detachably attached to the top of the collection basket mounting frame 52. is configured to

Therefore, when an empty seedling box is to be collected, the operator or an assistant rotates and deploys the auxiliary seedling frame 74, and then removes the collection basket 45 from the collection basket mounting frame 52 so that the inside of the collection basket 45 is removed. Empty seedling boxes housed in can be collected together.

FIG. 14 is a schematic side view of the vicinity of the frame 77 supporting the auxiliary seedling frame 74 according to the embodiment shown in FIG. 12, and FIG. FIG. 14B is a schematic side view of the vicinity of the frame 77 showing a state in which the auxiliary seedling frame 74 is positioned forward.

FIG. 14(c) is a schematic side view showing only the motor unit, and FIG. 14(d) is a schematic side view showing only the rack gear unit.

In FIG. 14, the rack 44, the collection basket 45, the collection basket mounting frame 52, and the angle sensor 66, which will be described in detail later, are omitted for convenience.

In this embodiment, front and rear position adjustment mechanisms 53 are provided between the upper portions of the left and right frames 77 attached to the front portion of the traveling vehicle 2 and the pair of left and right auxiliary seedling frames 74, respectively. In this manner, the front-back position adjusting mechanism 53 can be used to slide the auxiliary seedling frame 74 in the front-back direction.

The front-back position adjusting mechanism 53 includes a motor unit 55 attached to the top of the frame 77 and a rack gear unit 59 to which the auxiliary seedling frame 74 is fixed.

The motor unit 55 includes a housing 68 , four rollers 70 attached to the housing 68 , a pinion gear 72 arranged in the housing 68 , and a motor 71 for rotating the pinion gear 72 . The motor 71 is configured to rotate in both directions.

On the other hand, the rack gear unit 59 includes a slide frame 73 having a substantially inverted T shape when viewed from the side, and a rack gear 75 fixed to the lower surface of the slide frame 73 and meshing with the pinion gear 72. It is configured to be slidable in the front-rear direction while being clamped by 70 .

When the motor 71 of the motor unit 55 is driven, the pinion gear 72 is rotated, and as a result, the rack gear unit 59 and the auxiliary seedling frame 74 are integrally slid forward and backward. In this embodiment, a front/rear switch (not shown) used to drive the motor 71 is provided in the operating portion 54, and the operator operates the front/rear switch to configure the bi-directional rotation type. A motor 71 can be used to drive a pinion gear 72 in either direction to slide an auxiliary seedling frame 74 back and forth. Therefore, when handing over an empty seedling box from the work vehicle 1 to the assistant on the front side of the ridge, the front/rear switch is operated to slide the auxiliary seedling frame 74 forward so that the assistant on the ridge can move forward. , Empty seedling boxes can be retrieved easily.

FIG. 15 is a partially enlarged view of the vicinity of the rack gear 75 of the longitudinal position adjusting mechanism 53 shown in FIG.

As shown in FIG. 15, an angle sensor 66 is provided in the vicinity of the rack gear 75 to detect the amount of sliding of the rack gear 75 in the front-rear direction. 93.

Here, when a positioning switch (not shown) provided separately on the operating portion 54 is operated, the motor 71 is driven, and the rack gear 75 is slid to the previously stored slide amount position. ing. With this configuration, the auxiliary seedling frame 74 can be easily slid to the usual position simply by operating the positioning switch. In this embodiment, when the positioning switch is operated, the rack gears 75 of the front-back position adjusting mechanisms 53 of the left and right auxiliary seedling frames 74 are simultaneously slid back and forth by the same amount. This is convenient, but it may be configured such that when the positioning switch is operated, one of the left and right auxiliary seedling frames 74 is slid to the same position as the last time.

Thus, in this embodiment, the amount by which the rack gear 75 is slid is stored in the storage unit 93 by the angle sensor 66, and when the positioning switch is operated next time, the same amount as the stored slid amount is stored. Although it is configured to drive the motor 71 so as to slide the rack gear 75, the provision of the angle sensor 66 is not necessarily required. For example, if the motor 71 is composed of a stepping motor, and the control amount of the stepping motor when the front/rear switch is operated is stored in the storage unit 93, it will be stored when the positioning switch is operated next time. By reading out the control amount data and simultaneously driving the left and right stepping motors with the same control amount, the same effects as in the embodiment shown in FIG. 15 can be obtained.

In this embodiment, the pair of left and right auxiliary seedling frames 74 are slidable in the front-rear direction by means of the motor 71. For example, instead of the motor 71, a rotary handle with a sprocket is provided, and the sprocket is used. The auxiliary seedling frame 74 may be slid forward and backward when the attached rotary handle is rotated. In this case, each auxiliary seedling frame 74 can be manually slid back and forth even when the engine 7 is not driven.

Furthermore, in the present embodiment, the auxiliary seedling frame 74 is configured to be rotated by a motor so as to be deployed in the front-rear direction. Alternatively, the auxiliary seedling frame 74, which can only be manually rotated (developed), may be configured to be slidable forward and backward by the forward and backward position adjusting mechanism 53. As shown in FIG. In addition, in these cases, similarly to the above, when the positioning switch is operated, the left and right rack gears 75 and the left and right auxiliary seedling frames 74 are simultaneously slid forward and backward by the same amount as the previous time. work efficiency can be improved.

FIG. 16 is a schematic side view of a longitudinal position adjusting mechanism 53 according to still another preferred embodiment of the present invention.

FIG. 16 shows how the operating lever 76 is rotated.

In this embodiment, the rack gear unit 59 and the auxiliary seedling frame 74 are configured to be manually slidable in the front-rear direction, and the rack gear 75 can be engaged at an arbitrary position by an operation lever 76 provided in the vicinity thereof. By stopping or operating the operating lever 76, the locking can be released.

Specifically, the tip 78 of the operating lever 76 is always biased by a spring and pressed against the rack gear 75 , and the rack gear 75 is fixed by the operating lever 76 . Only while the operator rotates the upper portion of the operating lever 76 forward with a force exceeding the biasing force of the spring and the tip 78 of the operating lever 76 rotates downward and is separated from the rack gear 75 . , the rack gear unit 59 and the auxiliary seedling frame 74 are configured to be slid forward and backward by the operator.

On the other hand, FIG. 17 is a schematic side view of the vicinity of a frame 77 that supports an auxiliary seedling frame 74 according to yet another preferred embodiment of the present invention. FIG. 17B is a schematic side view of the vicinity of the frame 77 showing the state in which the auxiliary seedling frame 74 is positioned upward.

17(c) is a schematic side view of the vicinity of the rack gear unit 59 according to this embodiment, and FIG. 17(d) is a schematic side view showing only the vertical movement motor unit 84. As shown in FIG.

In this embodiment, as in the case of the embodiment shown in FIGS. 12 to 14, in addition to being provided with a front-rear position adjusting mechanism 53 for sliding the auxiliary seedling frame 74 in the front-rear direction, A vertical position adjusting mechanism 91 for vertically sliding the frame 74 is also provided, and the vertical sliding of the auxiliary seedling frame 74 will be described below.

The vertical position adjusting mechanism 91 includes a rack gear 92 (see FIG. 17(c)) attached to the slide frame 73 of the longitudinal position adjusting mechanism 53 shown in FIG. )).

The vertical movement motor unit 84 includes a housing 95, a vertical movement frame 94 to which the auxiliary seedling frame 74 is attached, two rollers 98 attached to the housing 95, and a pinion gear 99 arranged in the housing 95. , and a vertical motion motor 100 that drives the pinion gear 99 to rotate. The vertical motion motor 100 is configured to rotate in both directions. The vertical motion motor unit 84 is slidably attached to the slide frame 73 by two rollers 98 with the pinion gear 99 meshing with the rack gear 92 .

When the vertical motion motor 100 of the vertical motion motor unit 84 is driven, the pinion gear 99 is rotated, and as a result, the vertical motion motor unit 84 and the auxiliary seedling frame 74 are vertically slid integrally. In this embodiment, in addition to the front/rear switch for driving the motor 71, an up/down switch (not shown) for driving the up/down motion motor 100 is provided in the operation unit 54, and the operator operates the up/down switch. As a result, the pinion gear 99 can be driven in either direction to slide the auxiliary seedling frame 74 vertically by using the vertical motor 100 configured to rotate in both directions. Therefore, when passing an empty seedling box from the working vehicle 1 to an assistant who is on the ridge ahead, the front/rear switch can be operated to slide the auxiliary seedling frame 74 forward, and the up/down switch can be operated. Since the height position of the auxiliary seedling frame 74 can be adjusted according to the height of the ridge, work efficiency can be greatly improved.

Furthermore, in this embodiment, in addition to the positioning switches of the embodiment shown in FIGS. 12 to 14, the operating portion 54 is provided with a positioning switch (not shown) for setting the vertical position of the auxiliary seedling frame 74. ing.

Here, the vertical movement motor 100 is a stepping motor, and the control amount of the stepping motor (that is, the amount of sliding of the vertical movement motor unit 84) when the vertical switch is operated is stored in the storage section 93. there is When the positioning switch for setting the vertical position of the auxiliary seedling frame 74 is operated, the control amount when the vertical switch was operated last time and the vertical movement motor 100 was driven (that is, the slide amount of the vertical movement motor unit 84) ) is read out from the storage unit 93, and the vertical movement motor 100 is driven with the same control amount as the previous time. Therefore, by operating the positioning switch for setting the vertical position of the auxiliary seedling frame 74, the auxiliary seedling frame 74 can be set (lifted/lowered) to the same vertical position as the vertical position previously set. is good. At this time, the pair of left and right auxiliary seedling frames 74 may be simultaneously set to the same vertical positions as those previously set.

In this embodiment, the motor 71 and the vertical movement motor 100 are driven to slide the pair of left and right auxiliary seedling frames 74 in the front-rear direction and the vertical direction. A rotary handle with a sprocket is provided in place of at least one of the motors 100, and when the rotary handle with a sprocket is rotated, the auxiliary seedling frame 74 is slid forward and backward or up and down. may be configured. In this case, each auxiliary seedling frame 74 can be manually slid back and forth or up and down even when the engine 7 is not driven.

Furthermore, in this embodiment, the pair of left and right auxiliary seedling frames 74 are slidable in the front-rear direction and the up-down direction by driving the motor 71 and the vertical motion motor 100, which is shown in FIG. As in the case of the above embodiment, an operation lever may be provided so that each auxiliary seedling frame 74 can be slid in the front-rear direction only while the operation lever is being rotated.

In addition, in this embodiment, the auxiliary seedling frames 74 are configured to be rotatable (unfolded) so that they are arranged horizontally, but the auxiliary seedling frames 74 are configured to be unrotatable. good too.

In addition, in the embodiment shown in FIGS. 10 to 17, the configuration of each part other than the auxiliary seedling frame 74 is the same as in the embodiment shown in FIGS. 1 to 9. FIG.

The present invention is not limited to the above embodiments, and various modifications are possible within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say.

For example, in each embodiment shown in FIGS. 1 to 17, the work vehicle 1 is configured as a rice planter, but may be configured as other work vehicles such as a tractor and a combine harvester.

In each of the embodiments shown in FIGS. 1 to 17, a direction sensor is used as the "yaw direction angular velocity detection means". It may be configured to detect angular velocity.

Further, in each of the embodiments shown in FIGS. 1 to 17, turning control is started when the finger lever 23 is turned upward, but the starting condition for turning control is limited to this. can't

1 to 17, the steering wheel 56 is turned back to the rudder angle θdi based on the slip amount (degree of slip) detected using the angular velocity, so that the fuselage is excessively Although it is intended to prevent turning in a small turn, instead of turning back to the steering angle θdi, according to the slip amount (degree of slip) detected using the angular velocity, when the turn is finished, the steering wheel By adjusting the timing of returning the steering angle from .theta.d to the neutral position or its vicinity (step s13 in FIG. 6), the aircraft can be accurately turned to the turning target position. In this case, the higher the actual angular velocity of the traveling vehicle 2, the faster the timing, and the lower the actual angular velocity of the traveling vehicle 2, the slower the timing. can. Even if the timing to return to the neutral position is determined based on the heading of the aircraft (whether the angle difference between the heading of the aircraft and the next target line is greater than or equal to a predetermined value), It may be determined (whether or not the number of rotations of the running wheels since the turning is started is equal to or greater than a predetermined number) based on the number of rotations of the running wheels from the time the turning is started.

In addition, in each of the embodiments shown in FIGS. 1 to 17, as shown in step s1 in FIG. 6, data on the distance to the turning target position is acquired. , it is not always necessary to acquire the data of the distance to the turning target position.

Furthermore, in each embodiment shown in FIGS. 1 to 17, the steering wheel 56 is turned back based on the amount of slip (correlation value representing the degree of slip), that is, the difference between the ideal angular velocity and the actual angular velocity. However, if the difference between the ideal angular velocity, which is the amount of slip, and the actual angular velocity is greater than or equal to a predetermined value, the running wheels may be differentially locked. By constructing in this way, in the case where a slip of the traveling wheels occurs and the work vehicle turns on the spot without moving, it is possible to prevent the situation in which the work vehicle makes an excessively small turn. In addition, it is possible to improve the running driving force and eliminate the slip of the running wheels.

In each of the embodiments shown in FIGS. 1 to 17, it is determined each time whether the angle difference between the azimuth of the aircraft and the target line is 30°, 60°, 50°, or the angle θst or less or more. However, since the target line is a line parallel to the reference line, in steps s5, 7, 9 and 12 shown in FIG. is less than or greater than 30°, 60°, 50°, or θst.

Furthermore, in each embodiment shown in FIGS. 1 to 17, the controller 87 calculates the ideal angular velocity ωi using a parameter with a value of "0.071" set based on the tread width and wheelbase. However, when auxiliary wheels are separately attached to the traveling vehicle 2, for example, when the operator sets on the monitor 61 that the auxiliary wheels are attached, the controller 87 sets the parameter value to It may be configured to calculate the ideal angular velocity ωi by changing it to an appropriate value. With this configuration, even when the traveling vehicle 2 is attached with auxiliary wheels and the traveling vehicle 2 tends to make a large turn, the ideal angular velocity ωi at the time of turning can be accurately calculated, and the slip of the traveling wheels can be accurately controlled. It is possible to perform switchback control with consideration.

Similarly, when a sun visor is separately attached to the traveling vehicle 2, for example, when the worker sets on the monitor 61 that the sun visor is attached, the controller 87 changes the parameter value to an appropriate value. may be configured to calculate the ideal angular velocity ωi. When the position of the GNSS receiver 130 is changed due to the attachment of the sun visor to the traveling vehicle 2, the detected value of the vehicle speed is affected (the more forward the vehicle body 2 is located, the larger the amplitude = speed). Therefore, by configuring in this manner, even when a sun visor is attached to the traveling vehicle 2, the ideal angular velocity ωi during turning can be accurately calculated, and the steering-back control can be performed in consideration of the slip of the traveling wheels. can be done. In addition, not only when the sun visor is attached, but when the position of the GNSS receiver 130 is changed, the parameter value can be changed to an appropriate value on the monitor, for example, according to the position of the GNSS receiver 130. It may be configured as

Also, in each of the embodiments shown in FIGS. 1 to 17, as shown in FIGS. 9(a) to 9(f), depending on the depth of the field or the tilt of the machine, the Although it is configured to automatically adjust the angle of the line marker 40, it is configured to adjust the angle of the line marker 40 in the working posture in consideration of both the depth of the field and the inclination of the machine body. may For example, based on the detection signal output from the link sensor, the calculated height position of the seedling planting portion 63, that is, the depth of the field, determines the reference angle of the line marker in the working posture, and , and from there, the reference angle may be corrected according to the inclination of the aircraft body detected by the inclination detection sensor. With this configuration, it is possible to adjust the angle of the line-drawing marker in the working posture in consideration of both the depth of the field and the inclination of the machine body, so that a fixed line can be formed on the field. becomes possible.

1 Working vehicle 2 Traveling vehicle 3 Main frame 4 Belt type power transmission mechanism 5 Elevating link device 6 Rear frame 7 Engine 8 Front wheel 9 Rear wheel 10 Link base frame 11 Elevating link arm 12 Elevating hydraulic cylinder 13 Front wheel final case 14 Rear wheel transmission shaft 15 Power transmission mechanism 16 Finger lever sensor 17 Turn control switch 18 Center mascot 19 Planting ON/OFF switch 20 Subtransmission mechanism 21 Front wheel rotation sensor
23 finger lever 24 sub-transmission lever 25 hydrostatic continuously variable transmission 26 fertilizing device 27 planting clutch motor 28 marker switch 29 rear wheel rotation sensor 30 transmission case 31 front wheel axle 32 display 33 float sensor 34 marker motor 35 forward/reverse lever 36 Forward/reverse lever sensor 37 Inclination detection sensor 38 Center float 39 Side float 40 Draw marker 41 Draw body 42 Marker rod 43 Steering mechanism 44 Rack 45 Collection basket 46 Frame 47 Front cover 48 Cockpit 49 Control section
50 Rail 51 Rear wheel gear case 52 Collection basket mounting frame 53 Front-back position adjustment mechanism 54 Operation unit 55 Motor unit 56 Steering wheel 57 Steering motor 58 Steering sensor 59 Rack gear unit 60 Floor step 61 Monitor 62 Operation switch 63 Seedling planting unit 64 Planting Attachment device 65 Base 66 Angle sensor 67 Drive shaft 68 Housing 69 Planting tool 70 Roller 71 Motor 72 Pinion gear 73 Slide frame 74 Auxiliary seedling frame 75 Rack gear 76 Operation lever 77 Frame 78 Tip of operation lever 79 Straight assist lever 80 Orientation sensor 81 straight advance assist lever sensor 82 rear wheel axle 83 steering shaft 84 vertical movement motor unit 85 upper link arm 86 lower link arm 87 controller 88 electrohydraulic valve 89 processing unit 90 link sensor 91 vertical position adjustment mechanism 92 rack gear 93 storage unit 94 vertical movement Frame 95 Housing 96 Engine Rotation Sensor 97 Throttle Motor 98 Roller 99 Pinion Gear 100 Vertical Movement Motor 103 Electromagnetic Valve 105 Timer 108 Power Steering 111 Torque Sensor 130 GNSS Receiver 150 HST Servo Motor 200 Field 201 Side 202 of Field 203 of Field One side of the field 204 One side of the field 205 First planting start position 206 Second planting start position 207 First row planting start position 208 Broken line with arrow (reference line for straight control)
210 central region 211 peripheral region 212 peripheral region 213 peripheral region 214 peripheral region 218 starting point

Claims (8)

running vehicle and
a working machine that is attached to the traveling vehicle and performs work in a field;
a positional information acquiring means for acquiring positional information of the traveling vehicle;
A work vehicle comprising yaw direction angular velocity detection means for detecting an angular velocity in the yaw direction of the traveling vehicle,
The traveling vehicle has traveling wheels, a steering wheel that steers the traveling wheels, a motor that rotates the steering wheel, and control means that controls turning of the work vehicle by driving the motor,
The work vehicle, wherein the control means calculates a correlation value representing the degree of slip of the running wheels from the angular velocity in the yaw direction of the running vehicle during turning. The correlation value is a value of a difference between an angular velocity in the yaw direction of the running vehicle during actual turning and an ideal angular velocity in the yaw direction of the running vehicle during turning for turning to the target position. The work vehicle according to claim 1. In turning control, the control means drives the motor to change the steering angle of the steering wheel to a predetermined steering angle, and then rotates the steering wheel toward a neutral position by an angle corresponding to the correlation value. 3. The work vehicle according to claim 1, wherein switch-back control is performed so that the vehicle is turned on. In addition, equipped with a monitor,
4. The work vehicle according to claim 3, wherein the amount of control of the motor when rotating the steering wheel toward the neutral position can be increased or decreased on the monitor. A control value used to calculate the control amount of the motor is set on the monitor so that the control amount can be increased or decreased,
When the minimum value that can be set as the control value is set, the control means does not perform the switchback control,
When the maximum value that can be set as the control value is set, the control means rotates the steering wheel to the neutral position side by twice the angle compared to when 0 is set as the control value. 5. The work vehicle according to claim 4, wherein the work vehicle is movable. 6. The work vehicle according to claim 5, wherein different control values can be set on the monitor depending on whether the work vehicle turns left or right. 3. The work vehicle according to claim 2, wherein a parameter used for calculating said ideal angular velocity can be changed according to the position of said position information acquisition means. In turning control, the control means drives the motor to change the rudder angle of the steering wheel to a predetermined rudder angle, and then, according to the correlation value, moves the steering wheel to a neutral position when turning is finished. 3. The work vehicle according to claim 1, wherein the timing of starting to rotate to the side is adjusted.

Images