JPH0939853A - Method for controlling right and left inclination of working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure the safety of a working vehicle provided with a right and a left running devices, which can be separately displaced in the vertical direction, in the case where the vertical displacement quantity is deviated from the vertical limit by stopping the vertical displacement of the running device of the deviation side, and outputting the control signal, which is computed by setting the deviation of the height at 0, to the non-deviation side running device. SOLUTION: In a combine, a right and a left hydraulic cylinders 36R, 36L are separately telescoped so as to separately displace a right and a left running devices 2R, 2L in the vertical direction. The output of an inclination angle sensor for detecting the right and left inclination of a machine body and a right and a left height sensors are taken into a control device, and the control device computes the moving average of plural detection values so as to obtain the inclination value to be used for the posture control. At this stage, the upper limit and the lower limit in relation to the detection value of the right and the left height sensors are set, and in the case where any one of the height detection values is deviated from the limit value, the output to a solenoid of the deviation side is stopped, and while, a height deviation at the time of deciding the output to a solenoid of the opposite side is set at 0 so as to obtain the angle of inclination close to the target value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling left and right inclination of a work vehicle.

[0002]

2. Description of the Related Art Conventionally, in working machines such as combine harvesters, grains harvested by a mowing unit and threshed by a threshing unit are sorted by various sieves provided in a sorting unit to obtain fine grains.
If the machine is tilted to the left or right, the grain being selected may be biased to one of the left and right sides of the sheave, reducing sorting accuracy and efficiency.To prevent this, the tilt angle A sensor is attached, proportional and derivative control is performed based on the output of the same tilt angle sensor and the rate of change of the output with respect to time, and the left and right traveling devices are individually displaced up and down with respect to the aircraft, thereby maintaining the aircraft horizontally Left and right horizontal control is performed.

On the other hand, since it is necessary to maintain the aircraft body at a certain height above the surface of the earth, a left and right vehicle height sensor for detecting the vertical displacement amount with respect to the body of the left and right traveling device is provided between the body of the aircraft and the left and right traveling device. The sensor is attached and feedback control is performed with the average value of the sensor detection values as the vehicle height detection value.

[0004]

However, in the above-mentioned conventional left-right horizontal control and ground-height control, when the left-right traveling device reaches the upper and lower limits of displacement with respect to the main body, the vehicle height control operates and the left-right tilt control is impeded. It may be done.

Further, there is a problem that the vehicle height on the side not reaching the upper and lower limits is vertically displaced by the lateral inclination control, and the vehicle height gradually deviates from the target value.

[0006]

SUMMARY OF THE INVENTION In the present invention, a left and right traveling device which can be individually displaced vertically with respect to a machine body, an inclination angle sensor for detecting a left and right inclination of the machine body, and a vertical displacement amount of the left and right traveling device, respectively. In a work vehicle including a left and right vehicle height sensor for detecting and a control device for automatically controlling the left and right inclination of the machine body and the vehicle height, the control device controls the deviation of the inclination angle and the inclination angle. When a control signal for vertically displacing the left and right traveling devices is generated from the change rate of the vehicle height and the deviation of the vehicle height, and the vertical displacement amount of the left and right traveling devices deviates from the upper and lower limit preset in the control device. Stops the vertical displacement of the traveling device on the side deviating from the above limit,
It is intended to provide a lateral tilt control method for a work vehicle, which is characterized in that a control signal calculated with the deviation of the vehicle height set to 0 is output to the traveling device on the side not deviating.

[0007]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 and FIG. 2 show a combine A as a working vehicle that implements a unified control method of vehicle height and left / right inclination according to the present invention. The combine A is provided below the traveling machine body 1. A pair of left and right crawler-type traveling devices 2L and 2R that can be individually displaced vertically are arranged with respect to the traveling machine body 1, and the front end portion of the machine body frame 3 of the traveling machine body 1 is cut through the machine frame 4. Part 5 is mounted so that it can be adjusted up and down freely.
As a pre-mowing treatment device, a weed body 6, a grain culm raising device 8 and a mowing mechanism 7 are provided.

A mowing section height sensor (not shown) is attached to the mowing section 5, and the output of the sensor is provided by a control device separate from the above-mentioned unified control method of vehicle height and left / right inclination. Based on this, the reaper 5 is controlled so as to maintain a constant height above ground.

On the upper surface of the machine frame 3, a threshing section 11 equipped with a feed chain 10 for carrying the cut culms from the reaping section 5 is arranged on the right side of the front of the traveling machine body 1, and below the threshing section 11. A sorting unit 9 for sorting the threshed grains into refined grains is provided, and a grain tank 12 for storing the threshed / sorted grains is provided on the upper left side of the machine frame 3. The operation unit 13 is provided in front of the grain tank 12.

Further, to the traveling machine body 1, the power from an engine (not shown) is transmitted to the mowing section 5, the threshing section 11 and the sorting section 9 via the mission case 14, and the left and right sides of the mission case 14 are transmitted. The left and right crawler belts 17, 17 are driven via a drive sprocket 16 pivotally supported to the side.

The left and right traveling devices 2L and 2R are, as shown in FIGS. 3 to 6, left and right longitudinal track frames 18 and 1, respectively.
The tension sprocket 20, 20 urged rearward by the urging means 19 provided at the rear end of the 8 and the left and right track frames 18, 1.
The lower wheel 8 is provided with a roller wheel 22, which is axially supported on the lower surface of the roller wheel 8 at appropriate intervals, and left and right crawler belts 17, 17 surrounding the drive sprocket 16.

In the figure, 23 is an equalizer support shaft, 24 is an equalizer, 25 is an equalizer wheel, and 26 and 27 are first and second wheel wheels, respectively.

The left and right traveling devices 2L and 2R are configured to be individually vertically displaceable with respect to the machine body frame 3. Since the left and right traveling devices 2L and 2R are configured symmetrically, the left traveling device 2L will be described. The left traveling device 2L is provided with a chassis 30 having a longitudinal length in the lower part of the body frame 3, and the chassis 30
The bending parts of the front and rear bell cranks 32 and 32 are rotatably pivoted through front and rear support shafts 33 and 33, which respectively penetrate the front and rear lower parts of the front and rear parts of the front and rear bell cranks. The lower ends 32a of the 32, 32 are pivotally attached to the front and rear pivots 39, 39 projecting from the inner surface of the track frame 18, so that the chassis 30, the front and rear bell cranks 32, 32 and the rack frame 18 can be connected to each other. A parallel link mechanism is formed, and a left hydraulic cylinder 36L is interposed between the upper end 32b of the rear bell crank 32 and the hydraulic cylinder supports 35, 35 protruding from the machine frame 3 to extend and contract the left hydraulic cylinder 36L. By the operation, the track frame 18 can be displaced vertically with respect to the machine body frame 3. In the figure, 36R is a right hydraulic cylinder, and 34 is a connecting rod.

With the above structure, as shown in FIG. 6, the left and right traveling devices 2L and 2R can be individually displaced vertically with respect to the machine body by individually expanding and contracting the left and right hydraulic cylinders 36L and 36R.

The combine A is subjected to the vehicle height and left / right inclination unified control method of the present invention. First, a control device 50 for carrying out the control method will be described.

The control unit 50, as shown in FIG.
It is composed of a 51, a calculation unit 52, a memory 53, a control output unit 54, and an operation unit 55.

The detecting section 51 is attached to the machine body and detects the left and right inclination of the machine body as a voltage at a predetermined sampling period. This inclination detection value (in this embodiment, 2.25 V for inclination of -7.5 ° to + 7.5 °) is detected. 〜4.25V) to the calculation unit 52, and the inclination angle sensor 56 and the cylinders of the left and right hydraulic cylinders 36L and 36R and the piston rod, and each hydraulic cylinder 36L at a predetermined sampling cycle. Stroke detection of 36R expansion / contraction (in this embodiment, 1.5V to full stroke)
Left and right vehicle height sensors 57L and 57R that detect the vertical displacement of the left and right traveling devices 2L and 2R with respect to the aircraft via
56,57L, 57R and A / D converters 58,58,58 having a resolution of 10 bits respectively provided between the arithmetic unit 52, and a threshing switch 60 interlocking with the threshing clutch provided in the threshing unit 11. , The manual leftward tilt switch 61L, the manual rightward tilt switch 61R, the automatic switch 63, and the automatic set switch 64 provided in the operation unit 13.
The outputs of the sensors 56, 57L, 57R and the switches 60, 61L, 61R, 63, 64 are input to the calculation unit 52.

The arithmetic unit 52 is composed of a microprocessor MPU, and has a control program described later, a first fuzzy table capable of deriving a tilt fuzzy output from the deviation of the tilt angle and the rate of change of the tilt angle, and the tilt. A memory 53, which stores a second fuzzy table capable of deriving a control output value from the fuzzy output and the deviation of the vehicle height, is connected to the detecting unit.
A calculation is performed according to a control program described later based on the detected value input from 51, and the result is output to the control output unit 54 as a control signal.

The control output unit 54 amplifies the control signal from the arithmetic unit 52 and powers the P for driving the left and right lifting solenoids SLU, SLD, SRU, SRD of the left and right solenoid valves 65L, 65R described below.
The WM control output is input to the operation unit 55.

The operating portion 55 is composed of the left and right hydraulic cylinders 36L, 36L.
Left and right solenoid valves 65L and 65R that communicate with R and left solenoid valve
It consists of 65L lift solenoids SLU and SLD and right solenoid valve 65R lift solenoids SRU and SRD.
By controlling the flow rate by the control signal from, the flow rate is controlled by the direction of the pressure oil sent to the hydraulic cylinders 36L, 36R and the duty ratio of the PWM control output. I have to.

In the arithmetic unit 52 of the control device 50 having such a configuration, in order to process the detection value input from the detection unit 51 and generate the control signal, the unified control method of the vehicle height and the lateral inclination according to the gist of the present invention is used. The switching of the control mode is described first.

The control modes include automatic mode, manual mode,
There are an initial setting mode and an automatic OFF mode, and the relationship between each switch operation and each mode will be described.

The target value for control in the automatic mode is set to a preset (for example, factory default) default value by the power-on or auto-set switch 64.

When both the threshing switch 60 and the automatic switch 63 are ON, the automatic mode is set. In other cases, the manual mode is set.

The inclination angle sensor 56 and the left and right vehicle height sensor 57
The L and 57R continue to process sensing and detection values even in the manual mode. When the manual mode ends, each target value is set to 5 consecutive points after the specified time has elapsed from the end of the manual operation. The moving average value of the detected values (hereinafter referred to as the moving average value) is updated and the mode is returned to the automatic mode.

The manual left tilt switch 61 is used to set each target value.
This is done by L and the manual right tilt switch 61R.

Manual left tilt switch 61L and manual right tilt switch
When either one of 61R is turned ON, the automatic mode is switched to the manual mode, and the target value of the tilt angle is detected by the tilt angle sensor 56 after a predetermined time (1 sec in this embodiment) after the switch is turned OFF. Updates to the moving average value and switches to automatic mode.

Manual left tilt switch 61L and manual right tilt switch
When 61R and ON are turned on at the same time, the automatic mode is switched to the manual mode, and when the manual operation is completed, the target value of vehicle height is changed to
Predetermined time from the end of manual operation (1 sec in this embodiment)
After the lapse of time, the moving average value of the detection values of the left and right vehicle height sensors 57L and 57R is updated to the moving average value, and the mode is switched to the automatic mode.

Threshing switch 60 is OFF, automatic switch 63
Is ON and the auto-set switch 64 is ON for a predetermined time (10 sec in this embodiment) or more, the initial setting mode is set, and the self-diagnosis output is continuously turned on and the lamp is displayed to indicate this. However, when the other control is not the manual mode, the automatic OFF mode is set instead of the initial setting mode.

In the initial setting mode, the manual left tilt switch 61
L and the manual right tilt switch 61R are simultaneously turned on for a predetermined time (10 seconds in this embodiment) or more, and the detection values of the left and right vehicle height sensors 57L and 57R are both in a predetermined voltage range (0.8V to 0.8V in this embodiment).
1.2V), set the upper limit value, which will be described later, to the value obtained by adding a predetermined value to the above detection value.
Both 57R detection values are within the specified voltage range (in this example,
If it is within 3.8V to 4.2V), the lower limit value described later is set to the value obtained by subtracting a predetermined value from the above detection value, and the mode is switched to the automatic mode.

In the automatic OFF mode, driving of all solenoids is stopped. Then, when the automatic switch 63 is ON and the threshing switch 60 is switched from ON to OFF, the control in which the target value of the vehicle height is set to the lower limit is continued until the output from the vehicle height and the inclination angle sensor enters the dead zone. To do. After that, when the output of the tilt angle sensor exceeds the dead zone, the left and right solenoids are driven until the detection values of the left and right vehicle height sensors 57L and 57R reach the lower limit values, and then the automatic mode is switched. Further, when either the manual rightward tilt switch 61R or the manual leftward tilt switch 61L is turned on or the threshing switch 60 is turned on during the normal operation, the control operation is stopped. Further, during the automatic OFF mode, the moving average value of the detection values of the left and right vehicle height sensors 57L, 57R is stored as the vehicle height target value.

When the auto set switch 64 is turned on and when the automatic off mode is changed to the automatic mode, the target value of the tilt angle is reset to the horizontal state.

Next, the control operation in the automatic mode will be described. In the present embodiment, the processing time can be shortened even with a control device having a low operation speed, which is configured by a microprocessor or memory having a small number of bits and a low clock frequency.
The fuzzy table is accessed in two steps to obtain a control output, which will be described with reference to FIG.

When the control in the automatic mode is started, the detection value of the inclination angle sensor 56 and the detection values of the left and right vehicle height sensors 57L and 57R are sequentially read into the arithmetic unit 52, and a moving average of five consecutive detection values is obtained. Is calculated as the tilt angle detection value, and the difference between this value and the tilt angle target value is defined as the tilt angle deviation.
Find one of the values when accessing the fuzzy table. The quotient obtained by dividing the tilt angle deviation by 8 is ±
If it is in the range of 7, the value is set. If this quotient is larger than 7, it is set to 7.

Further, a value obtained by subtracting the previously calculated inclination angle deviation from the recently calculated inclination angle deviation is used as the inclination angle change rate, and the other value when accessing the first fuzzy table is obtained from this inclination angle change rate value. . If the quotient obtained by dividing the inclination angle change rate by 8 is within ± 7, this other value is the value,
If this quotient is greater than 7, then 7; if less than -7, then -7
And

Table 1 shows a first fuzzy table set according to the fuzzy rules shown in Table 2, where the vertical axis represents the tilt angle deviation and the horizontal axis represents the tilt angle change rate, and the above two values cross each other. The numerical value of the intersection is used as the slope fuzzy output when accessing the second fuzzy table.

The left and right vehicle height sensors 57L and 57R are used to obtain the left and right average values of the detected values, and the moving average of the five consecutive left and right average values is calculated as the vehicle height detection value. The difference from the target value is taken as the vehicle height deviation, and one value for accessing the second fuzzy table is obtained from this vehicle height deviation. The quotient obtained by dividing the vehicle height deviation by 16 is ± 7.
If the quotient is greater than 7, then 7
When it is less than -7, it is -7.

[0039]

[Table 1]

[0040]

[Table 2]

Table 3 shows a second fuzzy table set according to the fuzzy rules shown in Table 4, in which the vertical axis represents the inclined fuzzy output and the horizontal axis represents the vehicle height deviation. The value of the crossing point is controlled by the control output unit 54
A fuzzy output, that is, a control signal is output.

[0042]

[Table 3]

[0043]

[Table 4]

In the control output section 54, based on the fuzzy output, the lifting solenoids SLU, SLD,
Generates PWM control output to drive SRU and SRD.
This PWM control output is added with a predetermined minimum valve opening time (60 msec in this embodiment) and a time obtained by multiplying the absolute value of the fuzzy output by a predetermined coefficient (3 msec in this embodiment), and this is added to the pulse period (main cycle). In the embodiment, it is a pulse whose duty ratio is a value divided by 200 msec.

The PWM control output to the right (left) lifting solenoids SRU, SRD (SLU, SLD) of the right (left) solenoid valve 65R (65L) is as follows.

When the fuzzy output is positive, the fuzzy output is output to the right (left) up solenoid SRU (SLU) and not to the right (left) down solenoid SRD (SLD).

When the control output is 0, it is not output to the right (left) lift solenoid SRU, SRD (SLU, SLD).

When the control output is negative, no output is made to the right (left) ascending solenoid SRU (SLU), but the right (left) descending solenoid.
Output to SRD (SLD).

Further, the upper and lower limit values for the detection values of the left and right vehicle height sensors 57L and 57R are set, and when the detection value of either the left or right vehicle height sensor deviates from the upper limit value, it deviates. When the output to the up solenoid on the side is prohibited and the vehicle height deviation when determining the output to the up / down solenoid on the opposite side is set to 0 and the detection value of either the left or right vehicle height sensor deviates from the lower limit value In addition, the output to the descending solenoid on the deviating side is prohibited, and the vehicle height deviation when determining the output to the elevator solenoid on the opposite side is set to 0.

FIG. 9 shows an example of the control operation in the present embodiment. The posture of the machine body when the vehicle height is slightly higher than the target value and the vehicle is leaning to the left and right, and the respective control operation specifications therefor. Is shown.

As described above, the inclination angle sensor detects the deviation between the left and right inclinations of the machine body and the inclination change rate to obtain the inclination fuzzy output for accessing the second fuzzy table by the first fuzzy table. Since the second fuzzy table is accessed and the final fuzzy output is generated by the slope fuzzy output and the average value of the left and right vehicle height sensor outputs, the fuzzy output is reasonably added with the detection values of all the sensors. As a result, it is possible to uniformly control the lateral inclination of the body and the vehicle height.

By using the moving average of each detected value as the detected value, accidental disturbance of the detected value can be suppressed and accurate control of the vehicle height and the lateral inclination can be performed.

Further, by detecting the final state in the manual mode,
Since this is set as the target value of the vehicle height and the inclination angle, a separate device for setting the target value and a troublesome procedure are not required,
Moreover, the target value can be set sensuously according to the situation.

Furthermore, after a lapse of a predetermined time from the end of the manual mode, the moving average of each detected value is set as the detected value,
It is possible to obtain the detection value in which the attitude of the machine body is stable and in which the random disturbance of the detection value is suppressed.

In the present embodiment, the fuzzy table is used so that the control device composed of a microprocessor or a memory having a small number of bits and a low clock frequency and a slow operation speed can perform high-speed processing. However, the fuzzy table is used. Without it, it is possible to calculate the control output according to the fuzzy calculation algorithm.

When the hydraulic pump 70 for driving the left and right solenoid valves 65L and 65R is also used as another hydraulic device 72 such as a mowing section lifting hydraulic cylinder, as shown in FIG. Solenoid switching valve 71 between valves 65L, 65R and hydraulic pump 70
When the left and right lifting solenoids SLU, SLD, SRU, SRD are output via the solenoid valve, the solenoid valve 71 must be used to output the pressure oil from the hydraulic pump 70 to the left and right hydraulic cylinders 36L, Switch to the 36R side.

[0057]

According to the present invention, the left and right traveling devices that can be individually displaced vertically with respect to the machine body, the inclination angle sensor that detects the left and right inclination of the machine body, and the left and right vehicles that detect the vertical displacement amount of the left and right traveling devices, respectively. With a high sensor and a controller,
In a work vehicle configured to automatically control the lateral inclination of the machine body and the vehicle height, the control device controls the vertical displacement of the lateral traveling device based on the deviation of the inclination angle, the rate of change of the inclination angle, and the deviation of the vehicle height. By generating the control signal for causing the control signal to be detected, the detection values of all the sensors are reasonably added to the control signal, and the lateral inclination of the body and the vehicle height can be controlled in a unified manner.

In particular, when the vertical displacement amount of the left / right traveling device deviates from the upper / lower limit set in advance in the control device, the vertical displacement of the traveling device on the side deviating from the above limit is stopped, and By outputting the control signal calculated with the deviation of the vehicle height as 0 to the traveling device, it is possible to bring the inclination angle of the airframe close to the target value while preventing the variation of the vehicle height.

[Brief description of drawings]

FIG. 1 is a side view of a work vehicle in which a unified control method of vehicle height and lateral inclination according to the present invention is implemented.

FIG. 2 is a front view of the same.

FIG. 3 is a side view of the traveling device.

FIG. 4 is a side view of the traveling device.

FIG. 5 is a plan view of the traveling device.

FIG. 6 is a front view of the traveling device.

FIG. 7 is an explanatory diagram showing a configuration of a control device.

FIG. 8 is a flowchart showing a control operation.

FIG. 9 is an explanatory diagram showing an example of a control operation.

[Explanation of symbols]

 A Work vehicle (combine) 2L Left traveling device 2R Right traveling device 50 Control device 56 Tilt angle sensor 57L Left vehicle height sensor 57R Right vehicle height sensor

Claims (1)

[Claims] 1. A left / right traveling device that is individually vertically displaceable with respect to a machine body, an inclination angle sensor that detects a lateral inclination of the machine body, and a left and right vehicle height sensor that detects a vertical displacement amount of the left and right traveling device, respectively. In a work vehicle equipped with a control device and configured to automatically control the lateral inclination of the airframe and the vehicle height, the control device controls the deviation of the inclination angle, the rate of change of the inclination angle, and the vehicle height. The deviation generates a control signal for vertically displacing the left and right traveling devices, and when the amount of vertical displacement of the left and right traveling devices deviates from the upper and lower limit limits preset in the control device, the side that deviates from the above limit. Stop the vertical displacement of the traveling device of, to the traveling device on the side that has not deviated,
A lateral tilt control method for a work vehicle, comprising outputting a control signal calculated with a vehicle height deviation set to 0.