Work vehicle

Abstract

The objective is to provide a work vehicle that improves workability and safety during automatic driving. [Solution] The system comprises a steering angle adjustment unit that adjusts the steering angle so that the vehicle body automatically travels straight ahead, and a control unit that acquires driving reference data that serves as the basis for automatic straight ahead travel based on position information and controls the steering angle adjustment unit based on the driving reference data.The system is characterized by having a lever that acquires the driving reference data, and the driving reference data is registered by operating the lever to acquire a first reference point and a second reference point within the field, making it possible to acquire the second reference point when the vehicle body travels more than a predetermined distance from the position where the first reference point was acquired, and having an alarm unit that alerts whether the situation is suitable for automatic straight ahead travel.

Description

Technical Field

[0001] The present invention relates to a work vehicle.

Background Art

[0002] Conventionally, there has been known a work vehicle that acquires position information of a work start position and a work end position by a work device and creates a reference line from the acquired position information (see, for example, Patent Document 1). Such a work vehicle has an automatic straight travel device that automatically travels straight along the created reference line.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described work vehicle, when creating a reference line, the distance traveled by the work device is set as the automatic travel distance. And when the work vehicle is automatically traveling straight, it notifies the operator of the timing to perform a turning operation based on the automatic travel distance.

[0005] However, in the process of creating a reference line, if the reference line is too short, there is a problem that accurate automatic straight travel setting cannot be performed. Also, it is impossible to know whether the vehicle is in a situation where automatic straight travel is possible, and it is impossible to accurately know the timing for the operator to perform a turning operation when the vehicle is automatically traveling straight.

[0006] The present invention has been made in view of the above, and an object thereof is to provide a work vehicle that improves workability and safety during automatic travel.

Means for Solving the Problems

[0007] In order to solve the above-described problems and achieve the object, a work vehicle (1) according to an aspect of the embodiment includes a position information acquisition unit (120) that acquires position information of a traveling vehicle body (2), a steering angle adjustment unit (110) that adjusts a steering angle so that the traveling vehicle body (2) travels straight automatically, a control unit (150) that acquires traveling reference data serving as a reference for automatic straight travel based on the position information and controls the steering angle adjustment unit (110) based on the traveling reference data, an attitude detection unit (170) that detects the attitude of the traveling vehicle body, and a steering angle detection unit (130) that detects the steering angle. An operating tool for acquiring the traveling reference data is provided. The traveling reference data is registered by acquiring a first reference point and a second reference point in a field by operating the operating tool. When the traveling vehicle body is not separated from the position where the first reference point is acquired by a predetermined distance, acquisition of the second reference point is prohibited. A notification unit is provided to notify that the second reference point can be acquired when the traveling vehicle body is at a predetermined distance from the position where the first reference point was acquired. When the attitude of the traveling vehicle body detected by the attitude detection unit (170) is an oblique attitude with respect to the traveling direction or the steering angle detected by the steering angle detection unit (130) is not a value indicating a straight travel state when executing automatic straight travel The notification unit indicates that the conditions for enabling automatic straight travel are not met. Notify This A work vehicle characterized by the above.

Effect of the Invention

[0008] According to the work vehicle according to an aspect of the embodiment, the straight travel performance in automatic straight travel can be improved. In addition, the workability in automatic straight travel can be improved.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

[0010] Hereinafter, a work vehicle according to an embodiment of the present invention will be described in detail with reference to the drawings using a riding type seedling transplanter 1. In addition, the constituent elements in the following embodiments include those that can be replaced by those skilled in the art and are easy to replace, or those that are substantially the same, that is, those within a so-called equivalent range. Furthermore, the present invention is not limited to the above-described embodiments, and can be variously modified and implemented without departing from the gist of the present invention. In the following, the entire seedling transplanter 1 may be referred to as the machine body.

[0011] FIG. 1 is an explanatory view showing an outline of the straight travel support of the seedling transplanter 1 according to the embodiment. The seedling transplanter 1 according to the present embodiment includes a traveling vehicle body 2 having a pair of left and right front wheels 4 and rear wheels 5, respectively, and a seedling planting unit 50 connected to the rear portion.

[0012] In the present embodiment, the straight travel support refers to a function of assisting the automatic straight travel of the seedling transplanter 1 in the field F by controlling the operation of the steering wheels based on the steering angle (cutting angle) of the steering wheels of the seedling transplanter 1 and the position information of the seedling transplanter 1. Here, the steering angle is the cutting angle of the front wheels 4, but for example, the steering angle of the steering wheel 32 (see FIG. 2) may be detected as the steering angle. In addition, the position information of the seedling transplanter 1 is acquired by a GNSS unit 120 (position information acquisition unit) (see FIG. 6) provided on the traveling vehicle body 2. In the following description, the front-rear and left-right direction references of the seedling transplanter 1 are based on the traveling direction of the traveling vehicle body 2 as viewed from the operator's seat 28 (see FIG. 2) where the operator can sit.

[0013] As shown in the figure, the seedling transplanter 1 performs seedling planting with a predetermined working width D while reciprocating within a predetermined working area G in the field F. At this time, if straight-ahead support is executed, as a manual operation by the operator using the handle 32, only the turning operation near the headland is required. For straight-ahead travel, the seedling transplanter 1 automatically travels along the automatic straight-ahead line L1. In FIG. 1, the reference sign L3 indicates the turning line by the manual operation of the seedling transplanter 1 at the headland. Also, the reference sign E indicates the advancing / retreating port of the seedling transplanter 1 to / from the field F.

[0014] The automatic straight-ahead line L1 of the seedling transplanter 1 by straight-ahead support is parallel to the reference travel line (travel reference data) L2 that is a reference for performing straight-ahead support. This reference travel line L2 is preset in the field F in accordance with the seedling planting direction. That is, taking the start position and end position of the straight-ahead support as the reference start point (hereinafter referred to as the "A point") and the reference end point (hereinafter referred to as the "B point") respectively, they are acquired by the travel reference registration unit 152 (see FIG. 6) provided in the seedling transplanter 1, and the line segment connecting the acquired A point and B point is registered as the reference travel line L2.

[0015] Hereinafter, with reference to FIG. 2, the specific configuration of the seedling transplanter 1 will be described. FIG. 2 is a side view of the seedling transplanter 1 according to the embodiment.

[0016] A seedling planting unit 50 is attached to the traveling vehicle body 2 of the seedling transplanter 1 so as to be able to move up and down via a seedling planting unit lifting mechanism 40 which is a lifting device. Also, the traveling vehicle body 2 is a four-wheel drive vehicle in which a pair of left and right front wheels 4 and a pair of left and right rear wheels 5 are both driven. By rotating the handle 32, the front wheels 4 which become the steering wheels are steered, and it is possible to travel on the field F or the road between fields F.

[0017] Further, the traveling vehicle body 2 includes a main frame 7 disposed substantially at the center of the vehicle body, an engine 10 which is a prime mover mounted on the main frame 7, and a power transmission device 15 that transmits the power of the engine 10 to the front and rear wheels 4, 5 and the seedling planting unit 50. In this seedling transplanter 1, an internal combustion engine such as a diesel engine or a gasoline engine is used as the power source, the engine 10, and the generated power is used not only to move the traveling vehicle body 2 forward and backward, but also to drive the seedling planting unit 50.

[0018] Further, the power transmission device 15 includes a hydraulic continuously variable transmission (hereinafter referred to as "HST") 16 that shifts and outputs the driving force transmitted from the engine 10, and a power transmission unit 17 that transmits the power from the engine 10 to the HST 16.

[0019] The power transmission device 15 also has a transmission case 18. That is, the driving force from the engine 10 is transmitted to the HST 16 via the power transmission unit 17, and the power shifted by the HST 16 is transmitted to the transmission case 18. The transmission case 18 is provided with a sub-shifting mechanism (not shown) that switches between a high-speed mode and a low-speed mode, which will be described later, and is attached to the front part of the main frame 7.

[0020] Part of the power transmitted from the transmission case 18 to the front wheels 4 and the rear wheels 5 can be transmitted to the front wheels 4 via the left and right front wheel final cases 13, and the rest can be transmitted to the rear wheels 5 via the left and right rear wheel gear cases 22. The left and right front wheel final cases 13 are disposed on the left and right sides of the transmission case 18, respectively. The left and right front wheels 4 are connected to the left and right front wheel final cases 13 via axles 131, and such front wheel final cases 13 can be driven in response to the steering operation of the steering wheel 32 to steer the front wheels 4.

[0021] Similarly, the rear wheels 5 are connected to the left and right rear wheel 5 - speed cases 22 via axles 220. On the other hand, power is transmitted from the transmission case 18 to the seedling planting unit 50 via a planting clutch 500 provided at the rear of the traveling vehicle body 2 from a work implement drive shaft (not shown). The planting clutch 500 is operated by a planting clutch motor 510 (see FIG. 6) connected to a controller 150 (see FIG. 6) which will be described in detail later.

[0022] The engine 10 is disposed substantially at the center in the left - right direction of the traveling vehicle body 2 and protrudes upward from the floor step 26 on which the operator places his / her feet when boarding. The floor step 26 is provided across the front part of the traveling vehicle body 2 and the rear part of the engine 10 and is attached to the main frame 7. A part of it is in a lattice shape, so that mud on the shoes can be dropped onto the field F. Also, a rear step 27 which also serves as a fender for the rear wheel 5 is provided behind the floor step 26. The rear step 27 has an inclined surface that slopes upward as it goes backward and is disposed on each side of the engine 10.

[0023] Also, the engine 10 protrudes upward from these floor step 26 and rear step 27, and an engine cover 11 that covers the engine 10 is disposed on the part protruding from these steps 26, 27.

[0024] And, an operator's seat 28 on which the operator sits is installed on the upper part of the engine cover 11, and an operation unit 30 is provided in front of such an operator's seat 28 and at the front - side center of the traveling vehicle body 2. Such an operation unit 30 is disposed in a state of protruding upward from the floor surface of the floor step 26 and divides the front - part side of the floor step 26 into left and right.

[0025] The control unit 30 is provided with a steering post 315, and a handle 32 that can be steered by an operator is provided above the steering post 315. As shown in FIG. 3, a finger gap lever 34 is provided on the steering post 315. FIG. 3 is a schematic view of the steering post 315 seen from the front. The finger gap lever 34 is operated by an operator, for example, when acquiring points A and B. The finger gap lever 34 can rotate in the vertical direction.

[0026] Further, as shown in FIG. 4, a monitor 33 is provided on the steering post 315. FIG. 4 is a schematic view of the monitor 33. On the monitor 33, for example, a straight - ahead support lamp 331 that lights up when the machine body performs automatic straight - ahead running by straight - ahead support, an A - point lamp 332, a B - point lamp 333, and a GPS lamp 334 are arranged. Note that display lamps other than the lamps are arranged on the monitor 33. Also, the seedling transplanter 1 may have a plurality of monitors.

[0027] On the monitor 33, when point A is acquired by operating the finger gap lever 34, the A - point lamp 332 lights up. Also, when point B is acquired by operating the finger gap lever 34, the B - point lamp 333 lights up. On the monitor 33, when the machine body is in a state where it can perform automatic straight - ahead running, both the A - point lamp 332 and the B - point lamp 333 light up.

[0028] The GPS lamp 334 has three display lamps and changes the number of lit display lamps according to the GPS reception state. On the monitor 33, the operator is informed of the GPS reception state by such a display mode.

[0029] Also, at a predetermined position of the control unit 30, for example, a buzzer 215 which is an example of the notification device 200 is provided (see FIG. 6).

[0030] Returning to FIG. 2, in the control unit 30, a main shift lever 81 and a sub-shift lever 82 are provided near the steering post 315. The main shift lever 81 is provided on the right side of the control unit 30, and the sub-shift lever 82 is provided below the steering wheel 32.

[0031] The main shift lever 81 is a lever for switching the forward and backward movement and the traveling output of the traveling vehicle body 2. By operating the main shift lever 81, the operator can adjust the rotation angle of the trinion (not shown) of the HST 16 to adjust the speed of the traveling vehicle body 2.

[0032] The sub-shift lever 82 is a lever for switching the traveling mode that defines the traveling speed of the traveling vehicle body 2 between a low-speed mode and a high-speed mode according to the place where the vehicle travels. The mode switching is performed by a sub-shift mechanism provided in the transmission case 18 according to the position of the sub-shift lever 82.

[0033] In addition, an openable and closable front cover 31 is provided at the front part of the control unit 30. And a center mascot 350 as an index member serving as an index for traveling is attached so as to be positioned at the center of the front end of the front cover 31. In FIG. 2, for the sake of convenience, the illustration is omitted, but spare seedling mounts (not shown) are provided on the left and right sides of the front side of the traveling vehicle body 2.

[0034] The center mascot 350 is attached to the central position of the front part of the traveling vehicle body 2 and functions as a guide for the traveling direction when the operator sitting on the operator's seat 28 drives the seedling transplanter 1. Further, the center mascot 350 according to the present embodiment also functions as a notification device 200 for notifying the support status including whether or not the straight-ahead support described above can be executed.

[0035] The seedling transplanter 1 according to the present embodiment may use the center mascot 350 serving as the notification device 200 to notify information regarding the remaining amount of work materials such as seedlings and fertilizers provided in the seedling planting unit 50 in addition to the status of the straight-ahead support.

[0036] Since the center mascot 350 is always within the line of sight of the operator facing forward, the operator can constantly grasp the situation of the seedling transplanter 1 without diverting their line of sight from the front, which can greatly contribute to improving safety.

[0037] In the seedling transplanter 1 according to this embodiment, a GNSS unit 120 incorporating a receiving antenna 121 (see FIG. 6) is disposed on the traveling vehicle body 2. This GNSS unit 120 can acquire position information on the earth at predetermined intervals by acquiring GNSS coordinates at predetermined time intervals with the receiving antenna 121.

[0038] The GNSS unit 120 is attached to the top of an antenna frame 124 whose base end is connected to the front end side of the traveling vehicle body 2 so as to be located directly above the axle 131 of the front wheel 4. The antenna frame 124 is foldable, and the height of the antenna frame 124 in the normal state is set to a height such that it does not interfere with the head even when a standard average male stands up on the floor step 26.

[0039] In addition to the receiving antenna 121, the GNSS unit 120 according to this embodiment incorporates an inertial navigation device using a gyro sensor and an acceleration sensor (not shown) and a control board for controlling these.

[0040] As shown in FIG. 5, the antenna frame 124 is rotatably attached to a bumper 2a provided on the front side of the traveling vehicle body 2 (see FIG. 2). FIG. 5 is a perspective view of the antenna frame 124 viewed obliquely from the front. The antenna frame 124 includes two vertical frames 124a arranged in the left - right direction, a support frame 124b connected to the vertical frames 124a and formed in a U - shape in plan view, and a reinforcing frame 124c connecting the vertical frames 124a and the support frame 124b.

[0041] The vertical frame 124a is provided at its lower end with a rotating portion 124d that rotatably attaches the antenna frame 124 to the bumper 2a. The rotating portion 124d is attached to the bumper 2a by a rotating connector (not shown).

[0042] The vertical frame 124a is formed by being bent so that the upper side inclines rearward in a side view. An attachment portion 124e to which the GNSS unit 120 (see FIG. 2) is attached is formed on the upper end side of the vertical frame 124a.

[0043] At the rear end of the support frame 124b, a claw portion (not shown) that can be inserted into a first hole (not shown) formed in the front cover 31 and a second hole (not shown) formed rearward of the first hole is formed. In the normal state, the antenna frame 124 is fixed by inserting the claw portion into the first hole. Also, at the time of storage, by inserting the claw portion into the second hole, the antenna frame 124 is fixed to the traveling vehicle body 2 (the bumper 2a and the front cover 31) in a state of being rotated rearward (folded) with respect to the normal state. That is, at the time of storage, the antenna frame 124 is fixed to the traveling vehicle body 2 with the height of the GNSS unit 120 lowered.

[0044] The reinforcing frame 124c is formed in a bent shape so as not to contact the steering wheel 32 (see FIG. 2), the main transmission lever 81, etc. when the antenna frame 124 is rotated.

[0045] Returning to FIG. 2, the seedling planting unit 50 and other components will be described. The seedling planting unit 50 is attached to the rear part of the traveling vehicle body 2 so as to be able to move up and down via the seedling planting unit lifting mechanism 40. The seedling planting unit lifting mechanism 40 includes a lifting link device 41, and this lifting link device 41 includes a parallel link mechanism that connects the rear part of the traveling vehicle body 2 and the seedling planting unit 50. Such a parallel link mechanism has an upper link 41a and a lower link 41b, and these links 41a, 41b are rotatably connected to a link base frame 43 in the shape of a rear-view portal standing on the rear end of the main frame 7. And the other end sides of the links 41a, 41b are rotatably connected to the seedling planting unit 50. Thus, the seedling planting unit 50 is connected to the traveling vehicle body 2 so as to be able to move up and down.

[0046] Further, the seedling planting unit lifting mechanism 40 has a hydraulic lifting cylinder 44 that expands and contracts by hydraulic pressure, and the seedling planting unit 50 can be lifted and lowered by the expansion and contraction operation of the hydraulic lifting cylinder 44. The hydraulic lifting cylinder 44 is driven by the aforementioned HST 16, and by the lifting and lowering operation of the seedling planting unit lifting mechanism 40, the seedling planting unit 50 can be lifted to the non-working position or lowered to the ground working position (planting position).

[0047] Also, the seedling planting unit 50 can plant the range for planting seedlings in a plurality of sections or a plurality of rows. For example, it can be a seedling planting unit 50 for so-called six-row planting that plants seedlings in six sections.

[0048] Also, the seedling planting unit 50 includes a seedling planting device 60, a seedling placement table 51, and floats 47 (48, 49). Among these, the seedling placement table 51 is provided as a seedling placement member for loading a plurality of rows of seedlings at the rear part of the traveling vehicle body 2, has a seedling placement surface 52 for the number of planting rows partitioned in the left-right direction of the traveling vehicle body 2, and it is possible to place the mat-shaped seedlings with soil on each seedling placement surface 52.

[0049] The seedling planting device 60 is disposed below the seedling placing table 51 for placing seedlings, and is a device that takes seedlings from the seedling placing table 51 and plants them in the field F, and is supported by a planting support frame 55 disposed on the front side of the seedling placing table 51. The seedling planting device 60 has a planting transmission case 64 and a planting body 61. The planting body 61 is configured to be able to take seedlings from the seedling placing table 51 and plant them in the field F. The planting transmission case 64 can supply a driving force to the planting body 61.

[0050] Further, the planting transmission case 64 is configured to be able to supply the power transmitted from the engine 10 to the seedling planting unit 50 to the planting body 61. The planting body 61 is rotatably connected to the planting transmission case 64. The planting body 61 also has a planting rod 62 that takes seedlings from the seedling placing table 51 and plants them in the field F, and a rotary case 63 that rotatably supports the planting rod 62 and is rotatably connected to the planting transmission case 64.

[0051] The rotary case 63 is internally provided with a non-uniform speed transmission mechanism (not shown) that can rotate while changing the rotation speed when rotating the planting rod 62 by the driving force transmitted from the planting transmission case 64. Thereby, when the planting body 61 rotates, the planting rod 62 can rotate while the rotation speed changes according to the rotation angle with respect to the rotary case 63.

[0052] The seedling planting devices 60 configured in this way are arranged one by one for every two rows. That is, a plurality of seedling planting devices 60 are each assigned a planting row. Each planting transmission case 64 rotatably includes planting bodies 61 for two rows. That is, two rotary cases 63 are connected to both sides in the left-right direction of the machine body to one planting transmission case 64.

[0053] Further, the float 47 slides on the field surface for land leveling as the traveling vehicle body 2 moves, and has a center float 48 located at the center of the seedling planting unit 50 in the left-right direction of the traveling vehicle body 2 and side floats 49 located on both sides of the seedling planting unit 50 in the left-right direction.

[0054] In the center float 48 in this embodiment, a float potentiometer 154 (see FIG. 6), which functions as a hydraulic sensitivity mechanism for raising and lowering the seedling planting unit 50 in accordance with the conditions of the field F, is provided. Such a float potentiometer 154 can change the width of the sensitivity for detecting the vertical movement of the center float 48.

[0055] For example, if the sensitivity is made sensitive, even a small vertical movement of the center float 48 will be detected and a detection signal will be sent to the controller 150. On the other hand, if the sensitivity is made insensitive, small vertical movements of the center float 48 will not be detected, and only vertical movements with an amplitude equal to or greater than a certain value will be detected and a detection signal will be sent to the controller 150.

[0056] Also, on the front side at the lower position of the seedling planting unit 50, a rotary tiller 67 for tilling the field F is provided. This rotary tiller 67 is configured to be rotatable by the output from the engine 10 transmitted via the rear wheel 5 gear case 22, and is provided so as to be able to be raised and lowered by a rotary tiller motor 165 (see FIG. 6), which is an electric motor.

[0057] In the seedling transplanter 1 according to this embodiment, the controller 150 executes straight - line support on the condition that such a rotary tiller 67 for tilling is in contact with the ground. That is, the controller 150 executes straight - line support only when the rotary tiller 67 for tilling is in the ON state and the seedling planting operation is being performed.

[0058] Also, in the seedling transplanter 1, the controller 150 can acquire points A and B on the condition that the rotary tiller 67 for tilling is in contact with the ground. That is, the controller 150 can acquire points A and B only when the rotary tiller 67 for tilling is in the ON state and the seedling planting operation is being performed.

[0059] On both the left and right sides of the seedling planting unit 50, there are provided line-drawing markers 68 that form lines serving as a guide for the traveling direction in the next planting row. When the seedling transplanter 1 travels straight forward in the field F, the line-drawing markers 68 draw lines on the field F as marks when the seedling transplanter 1 makes a turn at the edge of the field F and then travels straight forward.

[0060] Also, a fertilizer application device 70 is mounted behind the operator's seat 28 on the traveling vehicle body 2. The fertilizer application device 70 includes left and right storage hoppers 71 for storing fertilizer, a feeding device 72 for feeding out the fertilizer supplied from the storage hoppers 71 in set amounts, a fertilizer hose 74 which is a fertilizer application passage for supplying the fertilizer fed out by the feeding device 72 to the field F, and a blower 73 for supplying conveying air to the fertilizer hose 74.

[0061] By this blower 73, the fertilizer in the fertilizer hose 74 is transferred to the seedling planting unit 50 side. Further, the fertilizer application device 70 has a fertilizer application guide 75 through which the fertilizer is transferred by the fertilizer hose 74, and a furrow opener 76 for dropping the fertilizer transferred by the fertilizer hose 74 into a fertilizer application groove formed near the side of the seedling planting row.

[0062] FIG. 6 is a functional block diagram centered on the controller 150 of the seedling transplanter 1. The seedling transplanter 1 according to the present embodiment can control each part by electronic control, and the seedling transplanter 1 includes a controller 150 as a control unit for controlling each part. This controller 150 is provided with a processing unit having a CPU (Central Processing Unit) or the like, a storage unit such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and further an input / output unit, and these are connected to each other and can transfer signals to each other. A computer program for controlling the seedling transplanter 1 is stored in the storage unit.

[0063] As shown in the figure, various actuators and sensors for acquiring information on each part are connected to the controller 150.

[0064] Connected to the controller 150 are, as actuators, for example, a throttle motor 100 that adjusts the intake air volume of the engine 10, a rotor motor 165 that raises and lowers the rotor 67 for land preparation, and a planting clutch motor 510 that operates the planting clutch 500. Although not shown in the figure, a trunnion drive motor that changes the rotation angle of the trunnion of the HST 16 is also connected to the controller 150.

[0065] In addition, connected to the controller 150 are various other sensors including a rudder angle sensor 130, a direction sensor 160, an attitude sensor 170, a tilt sensor 180, a seating sensor 190, a rotational speed sensor (detection unit) 195, and further, a lever sensor (not shown) that detects the operation amount of the main transmission lever 81 and the sub - transmission lever 82 as a tilt angle, and a vehicle speed sensor (not shown) that detects the vehicle speed of the traveling vehicle body 2.

[0066] The rudder angle sensor 130 is a sensor that detects the rudder angle when the front wheels 4, which are the steering wheels, are steered by the operation of the steering wheel 32. The rudder angle sensor 130 may detect the rudder angle based on the rotation angle of the steering wheel 32.

[0067] The direction sensor 160 is a sensor that detects the direction of the machine body. The controller 150 can derive the actual traveling direction of the machine body based on the value obtained from the direction sensor 160.

[0068] The attitude sensor 170 detects to what extent the attitude of the traveling vehicle body 2 is inclined with respect to the automatic straight - running line L1, and is composed of a gyro sensor or the like.

[0069] The tilt sensor 180 detects the tilt of the traveling vehicle body 2. The tilt sensor 180 detects the tilt of the traveling vehicle body 2 in the front - rear direction and the left - right direction. The tilt sensor 180 may be composed of a plurality of sensors. The tilt sensor 180 is, for example, an acceleration sensor.

[0070] The seating sensor 190 is a sensor provided on the operator's seat 28 and composed of a load cell, a pressure-sensitive film sensor, etc., and can detect that the operator is seated on the operator's seat 28.

[0071] The rotation speed sensor 195 detects the rotation speed of the tilling rotor 67. The rotation speed sensor 195 detects the rotation speed when the tilling rotor 67 touches the farm field F and rotates.

[0072] When the steering angle detected by the steering angle sensor 130 is not a value indicating that the traveling vehicle body 2 is traveling straight within an allowable range, or when the azimuth detected by the azimuth sensor 160 or the attitude detected by the attitude sensor 170 is not a value indicating the straight-ahead direction, the controller 150 can prohibit the straight-ahead support.

[0073] The value that the steering angle is within the allowable range for the traveling vehicle body 2 to travel straight is, for example, when the absolute value of the steering angle (cutting angle) of the front wheels 4 is 15 degrees or less. Also, after the traveling vehicle body 2 has turned, when the steering angle detected by the steering angle sensor 130 indicates a value that the traveling vehicle body 2 is not in a straight-ahead state (for example, 5 degrees), the straight-ahead support can also be prohibited.

[0074] Regarding the azimuth sensor 160 and the attitude sensor 170 as well, an allowable range is set, and if the azimuth or attitude outside the allowable range continues for a time set in the controller 150 or more, it is determined that the vehicle is not facing the straight-ahead direction, and the straight-ahead support is prohibited.

[0075] Also, when some trouble or the like occurs and the straight-ahead support of the seedling transplanter 1 is stopped, in order to improve safety or prevent work mistakes, when restarting the straight-ahead support, control is performed so that it is not restarted unless conditions such as the seedling planting unit 50 being lowered, the spare seedling platform being stored, and the planting clutch 500 being engaged are satisfied.

[0076] Also, a monitor 33 and a buzzer 215 that emits an alarm, etc. are connected to the controller 150 as the notification device 200.

[0077] When the controller 150 executes straight - line support, stops it, etc., it can notify the support status including this by using the buzzer 215 and the monitor 33. Therefore, the operator can easily recognize whether the current forward - tilted posture state of the machine body, the rudder angle after turning the machine body, the posture of the machine body, etc. are situations suitable for executing straight - line support. Therefore, for example, the operability of switching from a turning operation to straight - line support can be improved.

[0078] By the way, using such a buzzer 215 and monitor 33, the controller 150 can also notify the operator of an abnormality in the power transmission device 15 (such as gear slipping of the clutch mechanism), for example. Note that these monitors 33 and buzzers 215 are assumed to be provided in advance on the traveling vehicle body 2 in this embodiment, but the same functions can also be provided to a tablet terminal device (not shown) that can be brought in from the outside.

[0079] The seedling transplanter 1 also includes a steering device 110 that can be controlled by the controller 150 and a GNSS unit 120, and these are connected to the controller 150.

[0080] The steering device 110 includes a transmission mechanism (not shown) that is interlock - connected to the steering wheel 32, and also includes a straight - line support mechanism 310 that applies an arbitrary rotational force to the steering wheel 32, enabling automatic steering by the controller 150. The transmission mechanism includes a steering motor (rudder - angle adjustment unit) 112 that rotates the steering wheel 32.

[0081] When the controller 150 executes straight - line support, based on the position information acquired by the GNSS unit 120, it automatically steers the steering wheel 32 via the straight - line support mechanism 310 to maintain the traveling vehicle body 2 in the straight - ahead direction.

[0082] The GNSS unit 120 has a receiving antenna 121 that receives signals from artificial satellites used in GNSS, obtains the position information (coordinate information) of the transplanter 1 on the earth, and transmits the obtained position information to the controller 150.

[0083] In addition, various switches such as a finger gap lever 34, a float potentiometer 154, and a straight - ahead support on - off switch 210 are connected to the controller 150.

[0084] The finger gap lever 34 receives the operator's operation regarding the straight - ahead support. The finger gap lever 34 is operated by the operator when obtaining points A and B. Also, the finger gap lever 34 is operated when canceling the reference travel line L2.

[0085] The float potentiometer 154 is provided on the center float 48 that moves up and down following the unevenness of the field F, and senses the up - and - down movement of this center float 48, that is, the depth of the field F. The controller 150 raises and lowers the seedling planting unit 50 according to the sensed unevenness of the field F.

[0086] The straight - ahead support on - off switch 210 switches whether to perform the straight - ahead support. When the straight - ahead support on - off switch 210 is in the on state, for example, registration of the reference travel line L2 and execution of the straight - ahead support are possible. Also, when the straight - ahead support on - off switch 210 is in the off state, for example, registration of the reference travel line L2 and execution of the straight - ahead support become impossible.

[0087] The controller 150 has a travel reference registration unit 152 in which the reference travel line L2 and the reference travel distance in the straight - ahead support are registered. In order to make the transplanter 1 perform the straight - ahead support, a teaching operation is required in advance. The travel reference registration unit 152 registers, by the teaching operation, for example, the reference travel line L2 for executing the straight - ahead support and performing straight - ahead control. Also, the travel reference registration unit 152 registers the reference travel distance for notifying the operator of the turning position when the straight - ahead support is being executed.

[0088] The traveling reference registration unit 152 acquires a point A which is the start position of the straight-ahead support and a point B which is the end position thereof, respectively, and registers a line segment connecting the acquired points A and B as a reference traveling line L2.

[0089] By registering the reference traveling line L2, the traveling direction when the straight-ahead support is executed is registered. Further, by registering the reference traveling distance, it is possible to notify an operator, based on the straight-ahead distance of the traveling vehicle body 2, that, for example, the operator has approached a point where a turning operation is to be performed, that is, the field edge (ridge) has approached.

[0090] Next, the reference traveling line registration control according to the embodiment will be described with reference to FIG. 7. FIG. 7 is a flowchart for explaining the reference traveling line registration control according to the embodiment. Here, it is assumed that the reference traveling line L2 is not registered.

[0091] The controller 150 determines whether an operation for acquiring point A has been performed (S10). Specifically, the controller 150 determines whether the finger up lever 34 has been pushed downward for less than 2 seconds.

[0092] If the controller 150 determines that the operation for acquiring point A has not been performed (S10; No), the current process ends.

[0093] If the controller 150 determines that the operation for acquiring point A has been performed (S10; Yes), the controller 150 determines whether the tilling rotor 67 is in contact with the ground, that is, whether the seedling planting operation is being performed (S11).

[0094] If the tilling rotor 67 is in contact with the ground (ON state) (S11; Yes), the controller 150 acquires point A (S12) and starts counting the rotation speed of the tilling rotor 67 (S13).

[0095] When the rotor 67 for land preparation is not grounded (OFF state) (S11; No), the controller 150 notifies that the point A cannot be obtained (S14). For example, the controller 150 notifies that the point A cannot be obtained by sounding the buzzer 215.

[0096] After the controller 150 obtains the point A, it determines whether the rotor 67 for land preparation is maintained in a grounded state (ON state) (S15).

[0097] When the rotor 67 for land preparation is not maintained in a grounded state (S15; No), the controller 150 cancels the obtained point A (S16), stops counting the rotation speed of the rotor 67 for land preparation (S17), and notifies to that effect (S18). For example, the controller 150 notifies that the point A is canceled and the counting of the rotation speed of the rotor 67 for land preparation is stopped by sounding the buzzer 215.

[0098] When the rotor 67 for land preparation is maintained in a grounded state (S15; Yes), the controller 150 determines whether an operation to obtain the point B has been performed (S19). Specifically, the controller 150 determines whether the finger up lever 34 has been pushed downward for less than 2 seconds.

[0099] When an operation to obtain the point B has not been performed (S19; No), the controller 150 determines whether the rotor 67 for land preparation is maintained in a grounded state (ON state) (S15).

[0100] When an operation to obtain the point B has been performed (S19; Yes), the controller 150 obtains the point B (S20) and ends the counting of the rotation speed of the rotor 67 for land preparation (S21).

[0101] The controller 150 sets the reference travel line L2 based on the obtained points A and B, and registers the reference travel line L2 in the travel reference registration unit 152 (S22).

[0102] The controller 150 calculates a reference travel distance based on the counted number of rotations of the tilling rotor 67 and registers the reference travel distance in the travel reference registration unit 152 (S23).

[0103] Next, the update control of the reference travel distance according to the embodiment will be described with reference to FIG. 8. FIG. 8 is a flowchart for explaining the update control of the reference travel distance according to the embodiment. Here, it is assumed that the straight-ahead support on / off switch 210 is in the on state, and the reference travel line L2 and the reference travel distance are registered in the travel reference registration unit 152. Also, it is assumed that the traveling vehicle body 2 is turning based on the turning operation by the operator.

[0104] The controller 150 determines whether the traveling vehicle body 2 is turning (S30). Specifically, the controller 150 determines whether the steering angle is within a predetermined steering angle range based on the operator's steering wheel operation. The predetermined steering angle range is a range in which it can be determined that the traveling vehicle body 2 is turning and is set in advance. The controller 150 determines that it is turning when the steering angle is greater than the predetermined steering angle range. Also, the controller 150 determines that the turning has ended when the steering angle is within the predetermined steering angle range.

[0105] If the controller 150 determines that it is turning (S30; Yes), the current process ends.

[0106] If the controller 150 determines that it is not turning, that is, the turning has ended (S30; No), the seedling planting operation is started (S31). As a result, the tilling rotor 67 descends and contacts the ground.

[0107] The controller 150 starts the straight-ahead support (S32) and starts counting the number of rotations of the tilling rotor 67 (S33).

[0108] The controller 150 determines whether or not a turn has started (S34). Specifically, the controller 150 determines whether or not the steering angle has become larger than a predetermined steering angle range by the operator's steering wheel operation. When the steering angle becomes larger than the predetermined steering angle range, the controller 150 determines that a turn has started. Also, when the steering angle is within the predetermined steering angle range, the controller 150 determines that a turn has not started.

[0109] When the turn has not started (S34; No), the controller 150 continues the straight - line support until the turn starts (S35).

[0110] When the turn has started (S34; Yes), the controller 150 ends the straight - line support (S36) and ends the seedling planting operation (S37). As a result, the rotor 67 for land preparation rises and is no longer grounded.

[0111] The controller 150 ends the counting of the rotation speed of the rotor 67 for land preparation (S38) and calculates the traveling distance by the current straight - line support (S39).

[0112] The controller 150 determines whether or not the distance difference between the traveling distance in the previous straight - line support (previous process) and the traveling distance in the current straight - line support (current process) is smaller than a predetermined distance (S40). The traveling distance in the previous straight - line support is registered (stored), for example, in the travel reference registration unit 152. The traveling distance in the current straight - line support is registered (stored), for example, in the travel reference registration unit 152. By registering the traveling distance in the current straight - line support, the traveling distance in the previous straight - line support is deleted. Note that the distance difference is the absolute value of the difference between the traveling distance in the previous straight - line support and the traveling distance in the current straight - line support. The predetermined distance is a preset distance.

[0113] When the distance difference is smaller than a predetermined distance (S40; Yes), the controller 150 updates the reference travel distance (S41). Specifically, the controller 150 registers the travel distance by the current straight-ahead support as the new reference travel distance.

[0114] When the distance difference is equal to or greater than the predetermined distance (S40; No), the controller 150 ends the current process. That is, the controller 150 does not update the registered reference travel distance.

[0115] When straight-ahead support is being performed, the controller 150 notifies the turning position based on the reference travel distance. For example, after turning, when the traveling vehicle body 2 has traveled the turning distance by straight-ahead support, the controller 150 sounds the buzzer 215. The turning distance is set to a distance shorter by a preset distance than the reference travel distance.

[0116] In this way, the timing for notifying the turning position is set based on the reference travel distance. Therefore, if the reference travel distance is set to a constant value, when the length of the field F is not constant, the timing for notifying the turning position may not be appropriate.

[0117] For example, when the length of the field F increases, notification is performed at a timing before the appropriate turning position. On the other hand, when the length of the field F decreases, notification is not performed even when the appropriate turning position is reached.

[0118] In the present embodiment, since the reference travel distance is updated, even when the length of the field F is not constant, the turning position can be notified at an appropriate timing.

[0119] Also, the controller 150 may be able to execute the following control regarding straight-ahead support.

[0120] While the straight - ahead support is in progress, if the controller 150 is unable to receive the position information of the traveling vehicle body 2 from the GNSS unit 120, for example, when a failure of the GNSS unit 120 is detected, the straight - ahead support is terminated. Thereby, it is possible to prevent the traveling vehicle body 2 from traveling by straight - ahead support in a state where the position information from the GNSS unit 120 cannot be obtained.

[0121] While the straight - ahead support is in progress, if the finger - up lever 34 is pushed upward, for example, for less than 2 seconds, the controller 150 terminates the straight - ahead support.

[0122] While the straight - ahead support is in progress, if the height of the rotor 67 becomes equal to or greater than a preset constant value, the controller 150 terminates the straight - ahead support. Thereby, the termination of the straight - ahead support can be performed without depending on the operator's operation, and the workability can be improved.

[0123] Before the engine 10 is started after the main switch (not shown) of the transplanter 1 is turned ON, the controller 150 may turn off all the monitors 33. Thereby, when the engine 10 is not started, the operator can be made to recognize that the straight - ahead support cannot be performed.

[0124] After the engine 10 is started, the controller 150 may turn on all the monitors 33 for, example, 1 second. Thereby, the operator can be made to recognize that the state where the straight - ahead support can be executed has been reached.

[0125] After turning on all the monitors 33, when the alignment is in progress, since the reference values of the respective sensors are being detected, the controller 150 may set the HST 16 to the neutral position. Thereby, movement of the traveling vehicle body 2 during alignment can be suppressed, and the reference values of the respective sensors can be accurately detected.

[0126] After the monitor 33 is fully lit, if the alignment is completed, the controller 150 may check the operation of the GNSS unit 120. Also, the controller 150 may make the HST 16 changeable from the neutral position.

[0127] After the monitor 33 is fully lit, during alignment, the controller 150 may blink the monitor 33, for example, every 0.5 seconds, in the order of red, orange, and blue. Also, when the controller 150 lights red, for example, it may blink each of the lamps 331 to 334. Also, the controller 150 may blink each of the lamps 331 to 334, for example. Also, after the monitor 33 is fully lit, if it is during alignment, the controller 150 may, for example, display that it is during alignment on the monitor 33. Thereby, the operator can be made to recognize that it is during the initial setting.

[0128] After the engine 10 is started, if the GNSS unit 120 receives a signal, the controller 150 may sound the buzzer 215 once, for example. Thereby, the operator can be made to recognize that the GNSS unit 120 has received a signal.

[0129] Until the GNSS unit 120 receives a signal, the controller 150 may blink the monitor 33, for example, every 1 second, in the order of red, orange, and blue, and turn off each of the lamps 331 to 334.

[0130] Until the GNSS unit 120 receives a signal, the controller 150 may display that it is receiving on the monitor 33. Thereby, the operator can be made to recognize that the operator is checking the reception of the signal by the GNSS unit 120.

[0131] After the engine 10 is started, if the GNSS unit 120 cannot receive a signal even after, for example, 5 minutes have elapsed, the controller 150 may sound the buzzer 215. This allows the operator to recognize that the GNSS unit 120 cannot receive a signal.

[0132] After the engine 10 is started, if the GNSS unit 120 cannot receive a signal even after, for example, 5 minutes have elapsed, the controller 150 may blink each of the lamps 331 - 334 and turn off other monitors (not shown). This allows the operator to recognize that the GNSS unit 120 cannot receive a signal.

[0133] If the controller 150 receives a signal from the GNSS unit 120 after the engine 10 is started and, for example, 5 minutes have elapsed, the controller 150 may sound the buzzer 215, for example, once. Also, after sounding the buzzer 215, the controller 150 may turn on all the monitors 33 for, for example, 2 seconds. This allows the operator to recognize that the GNSS unit 120 has received a signal.

[0134] If the finger cup lever 34 is pushed upward for, for example, 5 seconds or more, the controller 150 may forcibly execute alignment. The controller 150 may sound the buzzer 215, for example, once at the start of forcibly executing alignment. This allows the operator to recognize that the alignment is being forcibly executed.

[0135] While forcibly executing alignment, the controller 150 may set the HST 16 to the neutral position. Also, the controller 150 may accept forced alignment only when the HST 16 is in the neutral position. This allows the alignment to be performed accurately.

[0136] When the GNSS unit 120 is in the reception state, the controller 150 acquires point A. When the controller 150 acquires point A when the finger up lever 34 is pushed downward, for example, in less than 2 seconds, when it becomes possible to acquire point A, the point A lamp 332 may be blinked at a predetermined acquirable cycle. Thereby, it is possible to make the operator recognize that the state is such that point A can be acquired. Further, when the controller 150 is acquiring point A, the point A lamp 332 may be turned on. Thereby, it is possible to make the operator recognize that point A is being acquired.

[0137] When the controller 150 is not in a state where point A can be acquired, the point A lamp 332 may be blinked at a predetermined non - acquirable cycle. Further, when the controller 150 is not in a state where point A can be acquired, the buzzer 215 may be sounded, for example, three times at the start of blinking of the point A lamp 332. Thereby, it is possible to make the operator recognize that point A cannot be acquired.

[0138] When point A has not been acquired and the finger up lever 34 is pushed upward, for example, in less than 2 seconds and a straight - ahead support start operation is performed, the point A lamp 332 may be blinked for a predetermined non - acquirable cycle, for example, for 3 seconds. Further, the controller 150 may sound the buzzer 215, for example, three times. Thereby, it is possible to make the operator recognize that the straight - ahead support cannot be started.

[0139] When point A has not been acquired, a straight - ahead support start operation is performed, and the GNSS unit 120 is receiving a signal, the controller 150 may cause the monitor 33 to display that points A and B have not been acquired. Further, the controller 150 may end the display on the monitor 33, for example, after performing the display for 5 seconds. Also, the controller 150 may end the display on the monitor 33 when points A and B are acquired. Thereby, it is possible to make the operator recognize that the straight - ahead support cannot be started.

[0140] When only point A is acquired, the controller 150 may erase the acquired point A when the finger up lever 34 is pressed downward, for example, for 2 seconds or more. Thereby, the point A can be erased and a new point A can be easily acquired. Further, when erasing the point A, the controller 150 may sound the buzzer 215 once, for example. Thereby, the operator can be made aware of erasing the point A.

[0141] When the main switch is turned off while point A is acquired and, for example, 2 hours or more have elapsed, the controller 150 may erase the acquired point A. Thereby, when the work is not performed for a long time, the operator can be spared the trouble of erasing the point A by automatically erasing the point A.

[0142] When point A is acquired, the controller 150 may enable the acquisition of point B. Thereby, it is possible to prevent point B from being acquired first.

[0143] The controller 150 acquires point A when the GNSS unit 120 is in a reception state. When the controller 150 acquires point B by pressing the finger up lever 34 downward, for example, for less than 2 seconds, when point B can be acquired, the point B lamp 333 may be blinked at a predetermined acquirable cycle. Thereby, the operator can be made aware that point B can be acquired. Further, when point B is being acquired, the controller 150 may turn on the point B lamp 333. Thereby, the operator can be made aware that point B is being acquired.

[0144] When point B cannot be acquired, the controller 150 may blink the point B lamp 333 at a predetermined non - acquirable cycle. Further, when point B cannot be acquired, the controller 150 may sound the buzzer 215 three times, for example, at the start of the blinking of the point B lamp 333. Thereby, the operator can be made aware that point B cannot be acquired.

[0145] When the controller 150 travels a distance greater than or equal to the B - point acquisition distance, which is set to, for example, 5 m, from the position where the A - point has been acquired by the traveling vehicle body 2, the controller 150 may be able to acquire the B - point. Also, the B - point acquisition distance may include a predetermined traveling time, such as 5 seconds. Thereby, the straight - running property of the reference traveling line L2 can be improved, and the straight - running property of the straight - running support can be improved.

[0146] When the finger - up lever 34 is pushed downward for less than 2 seconds, for example, to acquire the A - point, the controller 150 may display on the monitor 33 that the B - point cannot be acquired while the traveling vehicle body 2 travels the B - point acquisition distance from the position where the A - point has been acquired. Thereby, the operator can be made aware that the B - point cannot be acquired.

[0147] The controller 150 may end the display on the monitor 33 that the B - point cannot be acquired when the traveling vehicle body 2 travels the B - point acquisition distance. Thereby, the operator can be made aware that the B - point can be acquired.

[0148] When the B - point has been acquired and the finger - up lever 34 is pushed downward for 2 seconds or more, for example, the controller 150 may erase the acquired A - point and B - point. Thereby, the A - point and B - point can be erased, and new A - point and B - point can be easily acquired. Also, when erasing the A - point and B - point, the controller 150 may sound the buzzer 215 once, for example. Thereby, the operator can be made aware of erasing the A - point and B - point.

[0149] When the main switch is turned off in a state where the A - point and B - point have been acquired and, for example, 2 hours or more have passed, the controller 150 may erase the acquired A - point and B - point. Thereby, when the work is not performed for a long time, the operator's labor for the erasing work can be saved by automatically erasing the A - point and B - point.

[0150] When only point A is acquired and point B is not acquired by the controller 150, and the finger up lever 34 is pushed upward for less than 2 seconds to perform a straight-ahead support start operation, for example, the point A lamp 332 and the point B lamp 333 may be blinked at a predetermined non-acquirable period, for example, for 3 seconds. Further, the controller 150 may sound the buzzer 215, for example, three times. Thereby, the operator can be made to recognize that the straight-ahead support cannot be started.

[0151] When the controller 150 is capable of performing straight-ahead support, the lamps 331 to 334 may be blinked so that the traveling direction enters the target direction. Thereby, the operator can be made to recognize the traveling direction.

[0152] When the traveling direction is deviated to the right side of the target direction by, for example, 3 degrees or more, the controller 150 may blink the point A lamp 332. Further, when the traveling direction is deviated to the left side of the target direction by, for example, 3 degrees or more, the controller 150 may blink the point B lamp 333. Thereby, the operator can be made to recognize the deviation of the traveling direction.

[0153] When the controller 150 is performing straight-ahead support, the straight-ahead support lamp 331 may be turned on or blinked. Thereby, the operator can be made to recognize that the straight-ahead support is being performed.

[0154] When the finger up lever 34 is pushed upward for less than 2 seconds to perform a straight-ahead support start operation in a state where the controller 150 cannot perform straight-ahead support, for example, the straight-ahead support lamp 331 may be blinked at a predetermined non-supportable period, for example, for 3 seconds. Thereby, the operator can be made to recognize that the straight-ahead support cannot be performed.

[0155] When the finger-up lever 34 is pushed upward, for example, for less than 2 seconds to perform a straight-ahead support start operation in a state where the controller 150 can perform straight-ahead support, the controller 150 starts the straight-ahead support. Thereby, the operator can freely set the straight-ahead support start position.

[0156] The controller 150 may be capable of performing straight-ahead support when the vehicle speed of the traveling vehicle body 2 is, for example, a detectable vehicle speed of 0.5 km / h or more. When the vehicle speed is low, the position detection accuracy of the GNSS unit 120 may decrease. The controller 150 can perform straight-ahead support when the vehicle speed of the traveling vehicle body 2 is, for example, 0.5 km / h or more, and can perform straight-ahead support in a state where the position detection accuracy in the GNSS unit 120 is good.

[0157] The controller 150 may be capable of performing straight-ahead support when the traveling vehicle body 2 is not moving backward. Further, the controller 150 can perform straight-ahead support when the steering angle (deflection angle) is small and the traveling vehicle body 2 is moving straight, for example, when the steering angle is smaller than a predetermined steering angle or when the deviation between the traveling direction and the target direction is less than 3 degrees.

[0158] Further, the controller 150 may be capable of performing straight-ahead support when the inclination of the traveling vehicle body 2 is, for example, less than 10 degrees. Further, the controller 150 may be capable of performing straight-ahead support when the traveling mode by the sub-transmission mechanism is not the high-speed mode. Further, the controller 150 may be capable of performing straight-ahead support when the height of the rotor 67 is less than a preset constant value. Further, the controller 150 may be capable of performing straight-ahead support when the GNSS unit 120 can receive a signal.

[0159] While in the straight - ahead support mode, if the vehicle speed of the traveling vehicle body 2 remains lower than the detectable vehicle speed of, for example, 0.5 km / h for, for example, 2 consecutive seconds, the controller 150 may terminate the straight - ahead support. This can prevent the straight - ahead support from being performed in a state where the position detection accuracy by the GNSS unit 120 is low.

[0160] While in the straight - ahead support mode, if the vehicle speed of the traveling vehicle body 2 remains lower than the support - travel - end vehicle speed of, for example, 0.4 km / h for, for example, 2 consecutive seconds, the controller 150 may terminate the straight - ahead support. This enables the straight - ahead support to be terminated regardless of the operator's operation when the traveling vehicle body 2 is predicted to stop, saving the operator's effort.

[0161] While in the straight - ahead support mode, if an abnormal communication with the GNSS unit 120 or an abnormality in the steering device 110 is detected, the controller 150 may terminate the straight - ahead support. This can prevent the straight - ahead support from being performed in a state where the accuracy of the straight - ahead support is low.

[0162] When the traveling mode of the auxiliary transmission mechanism is the high - speed mode, the controller 150 may display on the monitor 33 that the traveling mode of the auxiliary transmission is the high - speed mode. This allows the operator to recognize that the conditions for executing the straight - ahead support are not met.

[0163] If the display indicating that the conditions for executing the straight - ahead support are not met is displayed for, for example, 5 seconds, or if the traveling mode of the auxiliary transmission mechanism changes to the low - speed mode, the controller 150 may end the display.

[0164] When the height of the rotor 67 is equal to or greater than a preset constant value, the controller 150 may display on the monitor 33 that the height of the rotor 67 is equal to or greater than the preset constant value. This allows the operator to recognize that the conditions for executing the straight - ahead support are not met.

[0165] The controller 150 ends the display when the indication that the conditions for executing straight-line support are not met is displayed for, for example, five seconds, or when the height of the rotor 67 becomes lower than a preset constant value.

[0166] The seedling transplanter 1 according to the embodiment described above measures the working distance from when the rotor 67 for ground leveling, which is a working device, is turned on and touches the ground, to when the rotor 67 for ground leveling is turned off and does not touch the ground. If the difference in distance between the working distance during the previous straight support and the working distance during the current straight support is smaller than a predetermined distance, the seedling transplanter 1 registers the working distance during the current straight support as a reference working distance and updates the reference working distance.

[0167] As a result, when straight driving support is being performed and the turning position is notified based on the reference traveling distance, the reference traveling distance is updated, so that the turning position can be notified at an appropriate time. Therefore, even if the length of the field F is not constant, for example, the turning position can be notified at an appropriate time. This improves workability during straight driving support and improves safety during straight driving support.

[0168] When the soil leveling rotor 67 is in the ON state, the seedling transplanter 1 acquires points A and B for setting the reference running line L2. This allows the reference running line L2, which is the reference when performing straight-line support, to be accurately set in conjunction with the actual planting work. This improves the workability when performing straight-line support.

[0169] Even when the seedling transplanter 1 according to the modified example cannot acquire points A and B, if the planting operation is started and the tilling rotor 67 touches the ground, the reference travel distance may be calculated based on the rotation speed of the tilling rotor 67 and registered in the travel reference registration unit 152. Thereby, the reference travel distance can be registered earlier. Therefore, for example, when registering the reference travel line L2, even if the reference travel distance cannot be calculated, the turning position can be notified based on the reference travel distance registered during straight-ahead support in the next process.

[0170] Also, the seedling transplanter 1 according to the modified example may start counting the rotation speed of the tilling rotor 67 when the seedling planting unit 50 descends and the planting clutch 500 is engaged, that is, in the tightened state. Also, when the seedling planting unit 50 ascends and the planting clutch 500 is disengaged, that is, in the released state, the counting of the rotation speed of the tilling rotor 67 may be terminated.

[0171] Also, the seedling transplanter 1 according to the modified example may sound the buzzer 215 when the vehicle speed of the traveling vehicle body 2 detected by a vehicle speed sensor (not shown) is equal to or higher than a preset predetermined vehicle speed and the planting clutch 500 is engaged. Also, after sounding the buzzer 215, if the vehicle speed does not become lower than the predetermined vehicle speed even after a predetermined warning time has elapsed, the planting clutch 500 may be disengaged. Thereby, it is possible to suppress planting being performed at a high vehicle speed and suppress the plant spacing from becoming large. Also, it is possible to suppress the planting rod 62 from rotating at a high vehicle speed and suppress the deterioration of the planting body 61.

[0172] Further, in the seedling transplanter 1 according to the modified example, after the buzzer 215 sounds, if the vehicle speed does not become lower than the predetermined vehicle speed even after a predetermined warning time has elapsed, the rotation angle of the trunnion (not shown) of the HST 16 may be adjusted to reduce the vehicle speed. Even if the rotation angle of the trunnion of the HST 16 is reduced, if the vehicle speed does not become lower than the predetermined vehicle speed, the rotation angle of the trunnion of the HST 16 may be further reduced. Thereby, it is possible to suppress the planting operation from being performed while the vehicle speed is high, and to suppress the increase in the plant spacing. Also, it is possible to suppress the rotation of the planting rod 62 and the deterioration of the planting body 61 while the vehicle speed is high.

[0173] Note that after reducing the rotation angle of the trunnion of the HST 16 and the planting clutch 500 is disengaged, it may be automatically returned to the rotation angle of the trunnion corresponding to the position of the main transmission lever 81.

[0174] Further, in the seedling transplanter 1 according to the modified example, when the vehicle speed is equal to or higher than the predetermined vehicle speed, even if a planting switch (not shown) for switching whether to plant seedlings is turned on (ON state), the planting clutch 500 may be disengaged. Thereby, it is possible to suppress the planting operation from being performed while the vehicle speed is high, and to suppress the increase in the plant spacing. Also, it is possible to suppress the rotation of the planting rod 62 and the deterioration of the planting body 61 while the vehicle speed is high.

[0175] Further, in the seedling transplanter 1 according to the modified example, when the vehicle speed is equal to or higher than the predetermined vehicle speed, even if the planting switch is turned on until the main transmission lever 81 reaches the neutral position, the planting clutch 500 may be disengaged. Thereby, it is possible to suppress the planting operation from being performed while the vehicle speed is high, and to suppress the increase in the plant spacing. Also, it is possible to suppress the rotation of the planting rod 62 and the deterioration of the planting body 61 while the vehicle speed is high.

[0176] Further, in the seedling transplanter 1 according to the modified example, when the vehicle speed is equal to or higher than a predetermined vehicle speed, even if the planting switch is turned on or the planting clutch 500 is turned off until the trinion of the HST 16 reaches the neutral position. Thereby, it is possible to suppress the planting operation from being performed in a state where the vehicle speed is high, and to suppress the increase in the plant spacing. Further, it is possible to suppress the rotation of the planting rod 62 and the deterioration of the planting body 61 in a state where the vehicle speed is high.

[0177] Further, in the seedling transplanter 1 according to the modified example, when the vehicle speed is equal to or higher than a predetermined vehicle speed, even if the planting switch is turned on or the planting clutch 500 is turned off until the vehicle speed becomes zero or a predetermined low vehicle speed near zero. Thereby, it is possible to suppress the planting operation from being performed in a state where the vehicle speed is high, and to suppress the increase in the plant spacing. Further, it is possible to suppress the rotation of the planting rod 62 and the deterioration of the planting body 61 in a state where the vehicle speed is high.

[0178] Further, in the seedling transplanter 1 according to the modified example, when the vehicle speed is equal to or higher than a predetermined vehicle speed, until the main shift lever 81 reaches the neutral position, the trinion of the HST 16 reaches the neutral position, and the vehicle speed becomes zero or a predetermined low vehicle speed, even if the planting switch is turned on, the planting clutch 500 may be turned off. Thereby, it is possible to suppress the planting operation from being performed in a state where the vehicle speed is high, and to suppress the increase in the plant spacing. Further, it is possible to suppress the rotation of the planting rod 62 and the deterioration of the planting body 61 in a state where the vehicle speed is high.

[0179] Further, in the seedling transplanter 1 according to the modified example, when restricting the planting clutch 500 to the off state as described above, the buzzer 215 may be sounded. Further, the monitor 33 or the like may be blinked. Thereby, it is possible to notify the operator that the planting clutch 500 is restricted to the off state.

[0180] In addition, the seedling transplanter 1 according to the modification executes the centering control for moving the position of the seedling placing table 51 to the left end or the right end only when the main speed lever 81 is in the neutral position, the trunnion of the HST 16 is in the neutral position, and the vehicle speed is zero. It may accept an ON operation of a centering control switch (not shown). By enabling the centering control only when the vehicle speed is zero, it is possible to prevent the centering control from being executed during traveling.

[0181] In addition, the seedling transplanter 1 according to the modification may accept the ON operation of the centering control switch only when the main speed lever 81 is in the neutral position, the trunnion of the HST 16 is in the neutral position, the sub-speed lever 82 is in the PTO position, and the vehicle speed is zero. The PTO position is a position where power is not transmitted, that is, a "neutral" position. Thereby, it is possible to prevent the centering control from being executed during traveling.

[0182] In addition, when the ON operation of the centering control switch is performed on the seedling transplanter 1 according to the modification, if not all of the above conditions are satisfied, the buzzer 215 may be sounded. Also, the monitor 33 or the like of the seedling transplanter 1 according to the modification may be blinked. Thereby, it is possible to notify the operator that the switch operation is not accepted, that is, the centering control is not executed.

[0183] In addition, the seedling transplanter 1 according to the modification may start the centering control when the centering control switch is in the ON state, the planting clutch 500 is in the engaged state, the main speed lever 81 is in a position equal to or higher than a predetermined forward position, and the vehicle speed is zero. Thereby, malfunction of the centering control can be suppressed. The predetermined forward position is, for example, a position where the main speed lever 81 is operated 80% or more to the forward side.

[0184] Further, in the seedling transplanter 1 according to the modification example, when the pushing control switch is in the ON state, the planting clutch 500 is in the engaged state, the main transmission lever 81 is at a position equal to or higher than a predetermined forward position, and the sub-transmission lever 82 is at the PTO position, the pushing control may be started. Thereby, malfunction of the pushing control can be suppressed.

[0185] Further, in the seedling transplanter 1 according to the modification example, when the vehicle speed becomes non-zero during the execution of the pushing control, that is, when the traveling vehicle body 2 travels, the pushing control may be stopped. Further, in the seedling transplanter 1 according to the modification example, when the sub-transmission lever 82 is no longer at the PTO position during the execution of the pushing control, the pushing control may be stopped. When the pushing control is stopped, the buzzer 215 may be sounded. Further, the monitor 33 or the like may be blinked. Thereby, the operator can be notified that the pushing control has been stopped.

[0186] Further effects and modification examples can be easily derived by those skilled in the art. For this reason, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described as above. Therefore, various changes can be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and their equivalents.

Explanation of Reference Numerals

[0187] 1 Seedling transplanter 2 Traveling vehicle body 33 Monitor 67 Rotor (working device) 110 Steering device (steering angle adjustment unit) 120 GNSS unit (position information acquisition unit) 140 Auxiliary wheel setting dial 141 Steering angle adjustment setting dial 150 Controller (control unit) 195 Rotation speed sensor (detection unit)

Claims

【Claim 1】 A position information acquisition unit that acquires position information of a traveling vehicle body; A steering angle adjustment unit that adjusts the steering angle so that the traveling vehicle body travels straight automatically; A control unit that acquires traveling reference data serving as a reference for the automatic straight travel based on the position information and controls the steering angle adjustment unit based on the traveling reference data, a posture detection unit that detects the posture of the traveling vehicle body, and a steering angle detection unit that detects the steering angle; An operating tool for acquiring the traveling reference data is provided; The traveling reference data is registered by acquiring a first reference point and a second reference point in a field by operating the operating tool; When the traveling vehicle body is not separated from the position where the first reference point is acquired by a predetermined distance, acquisition of the second reference point is prohibited; A notification unit that notifies that the second reference point can be acquired when the traveling vehicle body is separated from the position where the first reference point is acquired by a predetermined distance; When executing the automatic straight travel, when the posture of the traveling vehicle body detected by the posture detection unit is an oblique posture with respect to the traveling direction or when the steering angle detected by the steering angle detection unit is not a value indicating a straight travel state, the notification unit notifies that the conditions for executing the automatic straight travel are not met. A work vehicle characterized by this.

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