JPH01166108A - Automatic steering device for working vehicle - Google Patents

Abstract

PURPOSE:To prevent the generation of the danger of a working vehicle by executing the calculation and the storage of a maximum inclination quantity at the tie of a teaching steering, interrupting an automatic steering, moving back and after that, stopping when the inclination quantity detected at the time of the automatic steering exceeds the above-mentioned maximum inclination quantity. CONSTITUTION:First, in a first operation in which a driver operates a steering wheel (not shown in figure) and makes the vehicle travel as the works, the inclination quantity of the working vehicle is detected by inclination detectors 9a and 9b and the calculation and the storage of the maximum inclination quantity are executed by a steering control part 30. Next, at the time of the automatic steering, boundaries are detected by boundary detectors 10l and 10r and a front wheel 2 is steered by the steering control part 30 so that the working vehicle may be automatically steered following the said boundaries. At this time, when the inclination quantity detected by the detectors 9a and 9b exceeds the stored maximum inclination quantity, the automatic steering is interrupted the working vehicle is moved back for a fixed time and after that, it is stopped.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a system for driving work vehicles such as tractors, rice transplanters, and lawn mowers along a predetermined route to perform various ground work in a work area. This invention relates to a device that automatically steers the vehicle.

[Prior art]

Conventionally, work vehicles equipped with automatic steering devices using teaching and regeneration control have been known for traveling in a work area and performing various ground work, such as plowing and frame work in a field with a tractor, mowing work in a garden with a lawn mower, etc. be. These vehicles are taught by manually or automatically steering a part of the work area, the outer periphery, or the entire track in advance, and based on the teaching information, a driving route within the work area is set, and the driving route is set. Along the route, ground operations are carried out using automatic steering equipment.

[Problem that the invention seeks to solve]

However, in the above-mentioned automatic steering system, there is a risk that the working vehicle may run onto a field ridge or an obstacle during ground work, making it impossible to steer the vehicle and, in the worst case, overturning the working vehicle.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an automatic steering device that can prevent dangers such as inability to steer or falling due to excessive inclination during automatic steering after being taught. shall be.

[Means for solving problems]

An automatic steering device for a work vehicle according to the present invention is an automatic steering device for a work vehicle that performs ground work along a travel path taught in advance in a work area, and includes a direction in which the work vehicle is traveling and a direction perpendicular thereto. a tilt detector for detecting a tilt amount in a direction; a maximum tilt amount storage means for calculating and storing a maximum tilt amount of the work vehicle detected by the tilt detector during the teaching; a comparison means for detecting an amount of inclination with the inclination detector and comparing the amount of inclination with the maximum amount of inclination while performing ground work; and means for causing a predetermined operation to be performed when it is determined that this is the case.

[Effect]

In the present invention, it is calculated by the tilt detector at the time of teaching,
The memorized maximum amount of inclination is compared with the amount of inclination detected during ground work during automatic steering, and if the amount of inclination is greater than the maximum amount of inclination, a predetermined operation of the work vehicle will prevent a dangerous situation from occurring. Prevent occurrence.

〔Example〕

The present invention will be described in detail below based on drawings showing embodiments thereof. FIG. 1 is a left side view of a tractor equipped with an automatic steering device for a working vehicle according to the present invention (hereinafter referred to as the device of the present invention).

In the figure, 1 indicates a pair of left and right front wheels 2, 2 and a rear wheel 3,
The aircraft is supported by 3. The direction of the front wheel 2.2 is changed according to the turning operation of the steering handle 4 by the driver seated in the driver's seat 12 installed at the upper rear part of the aircraft body 1, and the direction of the front wheel 2.2 is changed. In addition, as will be described later, when automatic steering is performed by the device of the present invention, pressurized oil is supplied to the hydraulic cylinder 27 for steering (see FIG. 3). The direction can also be changed by electrically switching the feeding direction of the cylinder 27 and changing the operating direction of the cylinder 27. In addition, the rear wheels 3.3 are rotated by the power generated by the power unit 5 mounted on the front part of the aircraft body 1 being transmitted via the transmission 51, and the rotation of the rear wheels 3, 3 causes the aircraft 1 to perform work. Driving through a field, which is the land. The rotary 7, which is a work machine, is attached to the machine body 1 so as to be able to rise and fall freely in response to the vertical movement of a three-point link mechanism 6 attached to the rear of the machine body 1, and receives power from the power unit 5. When it is lowered into a field, it tills and crushes the soil in the field.

FIG. 2 is a schematic perspective view showing the configuration of the tilt detector,
A tilt detector 9a (or 9b) is fixedly installed on the left side of the driver's seat 20 to detect the amount of tilt of the aircraft 1 in the direction of travel (or the direction perpendicular to the direction of travel), that is, the amount of tilt of the aircraft 1 in the longitudinal (or left-right) direction. It is. This tilt detector 9a (or 9b) is
A potentiometer 90 is attached to a pivot shaft 92 of a weight body 91 that hangs vertically downward so that it can swing freely in the front-rear (or left-right) direction of the fuselage 1, and the casings 93 of the tilt detectors 9a and 9b are attached to the By utilizing the fact that the weight body 91 is inclined relative to the casing 93 when the weight body 91 is tilted together, the change in the output voltage of the potentiometer 90 corresponding to the change in the amount of inclination of the weight body 91 is applied to The amount of inclination of 1 is detected. The tilt detector 9a
The output potential of (or 9b) takes a predetermined reference value when the aircraft 1 is in a horizontal state, and becomes higher than the reference value when the aircraft 1 is tilted with the front (or left side) up.

FIG. 3 is a block diagram showing the configuration of the azimuth detector, and a azimuth detector 8 is fixed to the center of the upper part of the rotary 7 for detecting the azimuth in the traveling direction of the aircraft l. As the direction detector 8, a geomagnetic sensor is used, which is formed by winding a pair of detection windings 81 and 82 orthogonal to each other so as to surround the toroidal core 80 from the outside.
When is excited with alternating current at a predetermined frequency oscillated by an oscillator and a reference voltage is applied to the detection winding 81.82, the voltage induced in the detector vA 81.82 varies depending on the direction of the earth's magnetism. Taking advantage of the fact that it is maximum when orthogonal to
The circuit is constructed as shown in . Since the frequency component of the output voltage of the detection windings 81 and 82 is twice the frequency of the excitation current of the toroidal core 80, each output voltage is synchronously detected with reference to the twice the frequency oscillated by the oscillator. The signal is then outputted as an output through separate integration circuits and amplifiers. The output voltages of the detection windings 81 and 82 taken out in this way are given to the steering control section 30, which will be described later.
calculates the installation direction of the azimuth detector 8, in other words, the traveling direction of the aircraft 1, using the geomagnetic azimuth as an absolute reference, using the arc tangent of the ratio of these re-outputs.

Boundary detectors 101 and 1Or are attached to the upper front portions of the left and right sides of the bonnet that covers the power unit 5, respectively. Both the boundary detectors 101 and 1Or have their detection areas slightly forward of the front end of the machine body 1, and the distance between the left and right detection loads is changed according to the width of the work equipment such as a low clear installed at the rear of the machine body 1. It is installed so that it can be used.

The boundary detector 101, 1Or has a built-in light-emitting element and a light-receiving element, and projects light emitted from the former onto a test object, captures reflected light from the test object with the latter, and calculates the amount of received light. It outputs a voltage signal according to the voltage.

FIG. 4 is a block diagram of the control system of the device of the present invention, shown together with a plan view of the steering mechanism for the front wheels 2.2.

In the figure, reference numeral 20 denotes a front axle fixed to the lower part of the aircraft body 1 with its longitudinal direction being the left-right direction.
The knuckle arms 22 and 22 are pivotably supported around respective king pins 2121 so as to be rotatable in a horizontal plane. The knuckle arms 22.22 have their respective front ends attached to the front part of a pivot plate 24 which pivots in a horizontal plane about a pivot 23 provided upright on the top of the front axle 20, via separate link members 25.25. The steering hydraulic cylinder 27 is attached by locking the tip of its piston rond to the tip of an arm 26 protruding leftward from the middle of the rotating plate 24. ing. Therefore, when the hydraulic cylinder 27 moves forward (or retreats), the rotating plate 24 rotates clockwise (or counterclockwise) in FIG. 25.25
is transmitted to the left and right knuckle arms 22.22 via
The front wheels 2.2 are steered to the right (or left) with their respective nockle arms 22.22.

Further, a steering angle detector 15 using a potentiometer is provided at the position of the king pin 21, and the steering angle detector 15 detects the amount of rotation of the king pin 21, that is, the steering angle of the front wheels 2. , a positive voltage is output when the vehicle is being steered to the right when traveling straight, and a negative voltage is output when the vehicle is being steered to the left.

Further, at the positions of the left and right knuckle arms 22.22, there are mileage detectors 16N using reed switches.

16r is installed, which detects the rotation speed of the front wheels 2.2 by sensing the magnetic material attached to the front wheels 2.2, averages the detected left and right rotation speeds, and calculates the distance traveled. .

Pressure oil generated by a hydraulic pump 29 is supplied to the hydraulic cylinder 27 via a 4-point/3-position switching type electromagnetic directional switching valve ■, and the solenoid Sl of the electromagnetic directional switching valve V is energized. In this case, the pressure oil from the hydraulic pump 27 is fed to the oil chamber on the retracting side of the hydraulic cylinder 27, and the front wheels 2.2 are steered to the left by the operation of the steering mechanism as described above, and conversely, the front wheels 2.2 are steered in the electromagnetic direction. When the solenoid Sr of the switching valve V is energized, the front wheel 2°2 is steered to the right. Furthermore, solenoid S
1 and solenoid Sr are both demagnetized and the electromagnetic directional control valve (2) is in its neutral position, the front wheels 2.2 are kept at the current steering angle.

On the other hand, the forward and backward movement of the aircraft 1 is performed by the transmission 51,
The speed of the transmission 51 is changed by a speed change lever 52 disposed on the front right side of the driver's seat. Further, a shift motor 50 serving as a lever driving means for rotating the lever 52 is mounted on the base end pivot portion of the shift lever 52 coaxially with the pivot shaft of the shift lever 52, and the shift motor 50 or By manually rotating the speed change lever 52, the transmission 51 moves forward or backward.

Further, 30 is the direction detector 8, the tilt detector 9a,
9b, the mileage detector 16 j! , 16r and the boundary detector 101, which operates as described below based on the detection results of the boundary detector 101 and 1Or, and is a steering control unit that steers the aircraft 1 by energizing the solenoid SR or solenoid Sr of the electromagnetic directional control valve V. .

The steering control section 30 is connected to a power source via a key switch 31 for starting the engine, and is operable only when the engine is in a driving state.

An automatic switch 32 that is turned on when the driver seated in the driver's seat 12 instructs the steering control section 30 to start its operation is connected to the input port a1 of the steering control section 30. When the switch 320 is turned on, the human-powered boat a1 is set to a high level.

In addition, the human-powered boat az and the input port a of the steering control unit 30
:L is provided at the base end of the driving state selection lever 9, which is arranged at a position where it can be steered by the driver seated in the driver's seat 12, so as to be turned on according to the locking position of the lever 9. A taught running switch 33 and an automatic steering switch 34 are connected to each other, and when both the automatic switch 32 and taught running switch 33 are turned on, the input port a2 changes to a high level. Further, when the automatic switch 32 and the automatic steering switch 34 are turned on, the input port ()as is set to a high level. The running state selection lever 9 has a locking position where the teaching driving switch 33 is turned on, a locking position where the automatic steering switch 34 is turned on, and a locking position where both switches are turned off. The driver seated in the driver's seat 12 rotates the lever 9 to change the locking position, thereby controlling the steering control unit 30 (described later). It is possible to select three types of operation contents.

In addition, the outputs of the boundary detectors 10J and 10r are connected to changeover switches 111 and llr that are operated in conjunction with each other.
The changeover switch 111 and llr are the boundary detector 10
1 and 1Or outputs are distributed to the input of the buffer amplifier 44 and the input of the potentiometer 46, respectively.

The potentiometer 46 is adjusted to output 172 of the input voltage, and its output has the same gain as the buffer amplifier 44, and the other buffer amplifier 45 has the same gain as the buffer amplifier 44.
is given to.

The outputs of the buffer amplifiers 44 and 45 are input to the differential amplifier 43, and the output of the differential amplifier 43 is input to the differential amplifier 4.
Part 2 is a one-man operation. The output of the steering angle detector 15 is applied to the other input terminal of the differential amplifier 42 via a polarity inverter 40. Input port a4 of direction control unit 3°
is input.

Compare the output signal E of the differential amplifier 42 input to the control unit 30 with comparison reference values El (positive) and El (negative), respectively,
When E>E, the output capo-)b+ changes to high level to excite the solenoid Sr of the electromagnetic directional valve ■, and when E<
When El, solenoid St! output capo to excite)b
When Ez is changed to high level and Ez<E<El, output ports b, , b2 are both at low level.

Therefore, when E>El, the front wheels 2, 2 are steered to the right, and E
When <E t, the vehicle is steered to the left, and when E and <E<E, the vehicle is not steered.

The polarity inverter 40.41 is activated when the changeover switch 111°11r is switching the output from the boundary detector 101 to the potentiometer 46, inverts the polarity of the input signal, When the output from the detector 101 is switched to the side that supplies the buffer amplifier 44, the configuration is such that it does not operate and allows the input signal to pass through as is.

And the mileage detector 161 is installed in the input capo (as).
, 16r are input, the steering control section 30 detects the left and right rotational speeds within a certain period of time, calculates the average rotational speed Pa, and calculates the travel distance.

Also input port a6+ a? are given the output voltages from the two detection windings 8L82 of the azimuth detector 8, and the steering control unit 30 calculates the arctangent of the ratio between these output voltages based on an arithmetic formula stored in advance. The traveling direction of the aircraft 1 is calculated from.

Furthermore, the input capacitors (a8+a9) are supplied with the output voltages of each of tilt detectors 9a and 9b using potentiometers.

Then, automatic steering control that follows the boundary between the worked area and the unworked area, which will be described later, is performed by the signals input to the input ports aa+ae and a, and the input ports as+a
Input signals h l a7 + am and a perform teaching and automatic redirection control based on the memory.

On the other hand, the output ports bI and b2 of the steering control section 30 are connected to the solenoid Sr and the solenoid SN of the electromagnetic directional control valve (2), respectively, via separate excitation circuits (not shown), and the output port bt (or The solenoid Sr (or solenoid Sl) is energized in response to the high-level output of the output port bz), and the hydraulic cylinder 27 moves forward (or approaches). 2°2 is steered to the right (or left).

Further, the output ports b3 and b4 are connected to a shift motor 50 that shifts the speed change lever 52, and the output ports b3 and b4 are
(or b4) rotates forward (or reverse) in accordance with the high level output of
or neutral) position.

Now, the operation of the apparatus of the present invention constructed as above will be explained.

FIG. 5 is a partial plan view of a farm field showing the running state of the tractor, and FIG. 6 is a flowchart at the start of steering control.

The automatic steering by the device of the present invention is as shown in FIG.
1 in the field by the driver operating the handle 4.
In the first step of making the aircraft 1 run along the side while working with the rotary 7, a teaching run is performed in which the direction of movement and traveling distance of the aircraft 1 during this work are stored in the steering control unit 30 as a teaching running route. I do. Next, turn around and complete work area CTD
The tractor is automatically steered in accordance with the boundary INT of the unworked area UCT. When the boundary INT becomes undetectable during automatic steering based on this tracing, the aircraft 1 compares the azimuth data stored from the taught travel with the azimuth data of the azimuth detector 8, and Until the boundary can be detected, automatic steering is performed based on the azimuth data stored through this taught driving, and when performing this automatic steering, the driver first turns on the automatic switch 32 to operate the vehicle. A state in which the control unit 30 is commanded to start operation, and then the driving state selection lever 9 is rotated to lock it in the locking position where the teaching driving is selected, and the teaching driving switch 33 is turned on. Then, the teaching run is performed. After the taught driving is completed, the driver rotates the driving state selection lever 9 and locks it in the locking position where the automatic steering switch 34 is turned on. start the direction.

When the key switch 31 is turned on and connected to the power source, the steering control section 30 first checks the on/off state of the automatic switch 32 based on the level of the input port a, as shown in the flow chart of FIG.

Then, the automatic switch 32 is turned off, and the input capo)a
+ is at a low level, the steering control unit 30 resets its memory, registers, all flags, etc., waits until the automatic switch 32 is turned on, and if the automatic switch 32 is turned on and turned on. When capo) a+ is at a high level, the on/off states of the teaching running switch 33 and the automatic steering switch 34 are checked based on the levels of the input port a2 and the input boat a, and the teaching running switch 3
3 is turned on and the input port a2 is at a high level, the automatic steering switch 34 is turned on and the input port a2 is at a high level, according to the teaching running subroutine described later. Further, in accordance with the steering subroutine, when both the taught travel switch 33 and the automatic steering switch 34 are in the OFF state, each operates according to a turning subroutine to be described later. As described above, since the automatic steering switch 34 and the taught travel switch 33 are arranged to be turned on at different locking positions of the - driving state selection lever 9, both of them are turned on. By turning the automatic switch 32 on and off and rotating the driving state selection lever 9, the driver can cause the steering control unit 30 to follow the turning subroutine, teaching driving subroutine, and automatic steering subroutine, respectively. Actions can be commanded.

The above-mentioned teaching travel is performed only for one stroke at the left end of the field shown in FIG. 5, that is, the vehicle travels upward from the base point indicated by the circle mark, until it turns around at the upper side, and then ends.

FIG. 7 shows a flowchart of such teaching running,
FIG. 8 shows a flowchart of the direction detection subroutine, FIG. 9 shows a flowchart of the distance calculation subroutine, and FIG. 10 shows a flowchart of the maximum inclination calculation storage subroutine.

When the above-mentioned conditions are satisfied and the transition is made to the teaching driving subroutine, the steering control unit 30 calculates the maximum inclination amount CaMAX l CbMAX of the aircraft body 1 in the longitudinal and lateral directions, and detects the azimuth at every fixed distance. Write each to the storage device.

Further, in the direction detection subroutine, the direction data of the direction detector 8 is read a predetermined number of times, and the direction Si of a certain distance is determined by the average of the data. In the distance calculation subroutine, the left and right distance detectors 16 j! , the rotation speed p1. outputted from 16r. Pr is counted for a certain period of time T2, and the number of left and right rotations P
Calculate the average rotational speed Pa of l and Pr, and calculate the distance l per rotation, the average rotational speed Pa, and a certain time T.

Find the speed v1 from (Vz = PaX l / Tt
), this speed is integrated over time to find the distance traveled.

The obtained L is added to the distance L5 from the base point to find the distance of each point from the base point.

Next, the distance and direction S are determined! and is written and stored in the storage device. This is performed every time the vehicle 1 moves a certain distance until the driver locks the driving state selection lever 9 in the turning position.

FIG. 11 is a flowchart showing the automatic steering control. When the first turn is completed and the teaching driving is completed, the driver turns the driving state selection lever 9 to switch the automatic steering switch 34. Set it to the locking position where it can be turned on. Next, the steering control unit 30 detects the amount Ca of inclination in the longitudinal direction and the amount cb of inclination in the left-right direction, and combines them with the maximum amount of inclination CaMAX + Cb + 4Ax in each direction stored in the teaching driving.
The slope (jtCa.

Either of cb is the maximum slope amount CaMAX, CbMA
When X is exceeded, the steering control unit 30 interrupts automatic steering, and a high level output is made to the output port b1 to
As a result of the forward rotation, the speed change lever 52 is shifted from forward to backward, and the machine body I moves backward in the opposite direction to the tilting direction. After a certain period of time, the power unit 5 stops and the tractor stops.

In this way, during automatic steering, you may run onto obstacles such as ridges,
When the maximum tilt amount caMax l CtlMAX at the time of teaching is exceeded, the aircraft 1 performs a predetermined operation to prevent dangers such as falling.

When neither of the tilt amounts Ca and Cb exceeds the maximum tilt amount CaMAX + CbMAX, the boundary detector 10C1Or detects the boundary INT, and automatically steers the vehicle according to the boundary INT. For example, the boundary IN from top to bottom in Figure 5
When the aircraft is steered in accordance with T, that is, when there is an existing working area CTD on the right side of the aircraft 1, the changeover switch 11 shown in FIG.
β, 11r is switched in the opposite manner to that in FIG.

Now, if the outputs of the boundary detectors 10J and 10r are A and B, and the gain of the buffer amplifier 44.45 is k, the outputs to the differential amplifier 43 are %kA and kB, and the differential amplifier 4
Let the gain of 3 be ′ and k −k ′ =
The output C of the differential amplifier 43 is as follows.

C=K(B-VzA) The left boundary detector always detects the unworked area OCT as the detection area, whereas the right boundary detector 10r detects only the worked area CTD. In case, unworked area OCT
In the second case, only the boundary INT is detected, and in the third case, the detection area includes both the boundary INT and the boundary INT.

The surface of the already worked area CTD is very uneven and the light projected onto the surface is scattered, so the output of the boundary detector whose detection area is the already worked area CTD is approximately O. Therefore, in the first case B=0, in the second case A=B, and in the third case B
is a value between 0 and A.

In particular, when the boundary detector 10r is located above the boundary INT and its detection area includes half of the unworked area tlcT and half of the worked area CTD, B='AA. That is, when the output signal C of the differential amplifier 16 is 0, it indicates that the vehicle is traveling along the boundary INT.
If it is positive, it means that the front part of the machine 1 is closer to the right in Fig. 5, that is, closer to the unworked area UTD side, and if it is negative, the front part of the machine 1 is This shows that the state is shifted to the left in FIG. 5, that is, closer to the completed work area CTD side.

On the other hand, the output signal from the steering angle detector 15 is a voltage corresponding to the left and right steering angles of the front wheels 2°2 with respect to straight travel.
Since K is set in the gain in relation to the output signal, the output signal E=CD of the differential amplifier 42 becomes the required amount of change in steering angle from the state of the front wheels 2.2 at that time. There is. The output signal E is compared with the reference voltage values E+ and Ex as described above, and the steering is controlled.

Also, at this time, the boundary INT becomes undetectable, and the boundary INT
When the automatic steering that follows becomes impossible, the azimuth data SMi stored during the teaching drive described above is read, and the detected azimuth data S is compared with the memorized azimuth data SMi at the same distance from the base point. Based on the result, the steering control unit 30
Either output boat bl or b2 is output at high level, or neither output is output and aircraft 1 moves to the right.
Turn left or continue steering.

Note that when the automatic steering is in the opposite direction to the taught driving direction, that is, the fifth
When automatic steering is performed from top to bottom in the figure, the stored orientation data S, 4. cannot be read from the opposite direction.

As a result, even if a work vehicle that has been automatically steered following the boundary INT fails to detect the boundary INT mid-way, the automatic steering will not be interrupted and the vehicle will continue to follow the taught direction of the first stroke. It turns out.

This automatic steering control is also performed, similarly to the above-described taught driving, until the driver locks the driving state selection lever 9 in the turning position.

In this example, a geomagnetic sensor using a toroidal core was used as the direction detector for detecting the direction of travel. , a large number of reed switches, etc. may be provided, and a direction detector may be used which detects the rotational position of the magnetic needle and specifies the traveling direction of the aircraft 1 with respect to the direction of earth's magnetism.

Furthermore, in this embodiment, a tilt detector with a potentiometer attached to the pivot shaft of the weight body is used.
The present invention is not limited to this, but any device that can detect the amount of inclination may be used, such as a geomagnetic sensor that changes its output value when the sensor is tilted.

Furthermore, in this embodiment, the case where the device of the present invention is attached to a tractor has been described, but the device of the present invention can also be used for rice transplanters, rice transplanters, rice transplanters, etc.
Needless to say, the present invention can also be applied to other work vehicles such as harvesters and lawn mowers.

[Effect] - As detailed above, in the device of the present invention, the maximum amount of inclination is calculated and stored during teaching driving, and the amount of inclination detected during automatic operation is compared with the maximum amount of inclination, so that the tractor does not approach obstacles, etc. If the machine runs over the top and the amount of inclination exceeds the maximum amount of inclination, the automatic steering will be interrupted and the machine will move backwards for a certain period of time and then stop, which has excellent effects such as preventing dangers such as falling and providing a safe working environment. play.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a left side view of a tractor equipped with the device of the present invention, FIG. 2 is a schematic perspective view showing the configuration of an inclination detector, and FIG. FIG. 4 is a block diagram showing the configuration of the azimuth detector, FIG. 4 is a block diagram showing the configuration of the device of the present invention, FIG. 5 is a partial plan view of a field showing the running state of the tractor, and FIGS. 3 is a flowchart showing the operation details of the device. 1... Airframe 2... Front wheel 3... Rear wheel 7...
Rotary 8a, 8b... Orientation detector 9a, 9b...
・Inclination detector IQ l, tor...boundary detector
161, 16r... Mileage detector 27... Hydraulic cylinder 30... Steering control unit 50... Shift motor patent Applicant Yanmar Agricultural Machinery Co., Ltd. Agent Patent attorney Noboru Atsushi Kono 2 Figure' l! J7 Figure 9 Figure 8 *10 Figure 11

Claims (1)

[Scope of Claims] 1. In an automatic steering system for a work vehicle that performs ground work along a pre-taught course in a work area, the amount of inclination in the direction of travel of the work vehicle and in the direction perpendicular thereto is an inclination detector for detecting; a maximum inclination storage means for calculating and storing the maximum inclination of the work vehicle detected by the inclination detector during the teaching; , a comparison means for detecting an amount of inclination with the inclination detector and comparing the amount of inclination with the maximum amount of inclination; and when the comparison means determines that the amount of inclination is larger than the maximum amount of inclination, a predetermined amount of inclination is detected. 1. An automatic steering device for a work vehicle, comprising: means for causing the operation to take place.