JP2784065B2 - Steering control device for traveling work machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering control device for a traveling work machine including a pair of left and right traveling crawlers, such as a combine or a tractor for agricultural work or civil engineering.

[Conventional technology]

A traveling unit in a traveling work machine such as a combine or a tractor is constituted by a pair of left and right traveling crawlers, and each traveling crawler is driven by a set of one hydraulic pump and a hydraulic motor, in other words, the left and right traveling crawlers are driven. It is possible to execute forward and turn operations by driving with a left and right independent hydraulic drive system (two-pump, two-motor type).
No. 34972.

[Problems to be solved by the invention]

According to this prior art, a crop row detection sensor, each flow control valve for controlling the rotation speed of the left and right hydraulic motors, and an electrical control circuit, when there is no signal from the detection sensor, A straight-ahead command signal is given to the flow control valve to control the body to go straight. At the time of turning control, a reference signal at the time of straight-ahead is V1, a turning command signal of a detection sensor (V10), and an output signal on the left side. V2 = V1-V10
A subtraction circuit is provided with a right output signal V3 = V1 + V10 addition circuit, and a turning command signal is given to the flow control valve from the operation result of both circuits, and the rotation speed of each hydraulic motor with respect to the left and right traveling crawlers is determined. For example, at the time of a left turn, the traveling crawler on the left side (the inside of the turn) is decelerated, while the traveling crawler on the right side (the outside of the turn) is accelerated (increased in speed). An input signal is given to each of the flow control valves.

Therefore, in this prior art, when moving from the straight running state to the turning control, the speed of the traveling crawler outside the turning becomes higher than the speed at the time of going straight, and the speed of the traveling crawler inside the turning is reduced than that at the time of going straight. Therefore, there is a problem that a worker on the traveling work machine is likely to apply a centrifugal force that is suddenly swung out of the turn, and the centrifugal force is also likely to increase, making it difficult to perform safe traveling work. Further, since the turning radius of the traveling work machine rapidly changes in the direction of decreasing, there is a problem that the steering control for following the crop row or changing the direction is too sensitive.

An object of the present invention is to solve these problems.

[Means for solving the problem]

For this reason, in the present invention, power is transmitted to a pair of left and right traveling crawlers of the traveling work machine by left and right separate hydraulic driving means including a hydraulic pump and a hydraulic motor, and rotation of the left and right hydraulic motors is performed. In a traveling work machine configured to control the number of rotations, the deceleration per unit time of the number of rotations of the hydraulic motor inside the turn is smaller than the deceleration ratio of the number of rotations of the hydraulic motor outside the turn during the turn. It is configured to control so as to increase the ratio.

[Functions and effects of the invention]

As described above, in the present invention, when shifting from the straight traveling state to the turning control, the hydraulic motor inside the turning and the hydraulic motor outside the turning are simultaneously controlled to the deceleration side.

Since the reduction ratio (per unit time) of the rotation speed of the hydraulic motor inside the turn is set to be larger than the reduction ratio (per unit time) of the rotation speed of the hydraulic motor outside the turn, the speed reduction is performed. According to the difference in the ratio, the inside of turning is further decelerated from the outside, so that a smooth turning operation can be performed.

As described above, in the present invention, since the vehicle turns while decelerating both the inside of the turn and the outside of the turn, the outside of the turn is controlled to be on the speed increasing side than when traveling straight, and the conventional control of setting the inside of the turn to the deceleration side is performed, It does not cause a sudden change in the speed change rate inside and outside the turn, so it does not apply a sudden centrifugal force to the onboard operator, making it possible to perform extremely safe steering work and turning work easily. It has a great effect.

〔Example〕

Next, a description will be given of an embodiment. Reference numeral 1 denotes a traveling body of a general-purpose combine having a pair of left and right traveling crawlers 2a and 2b, on which a threshing device 3 is mounted, and inside a handling room of the threshing device 3 The handling cylinder is disposed so that its axis is along the traveling direction of the traveling machine body 1, and below it is provided with a swing sorting device using a receiving net and a sheave and a wind sorting device using the wind of Karumi Juan.

The harvesting pre-processing device 4 is opened at the front of the threshing device 3 and has a rectangular tubular feeder house 5 which can be raised and lowered by a hydraulic cylinder 6, and a horizontally long bucket-shaped platform 7 connected to the front end of the feeder house 5. And the platform 7
A scraper auger 8 is provided horizontally, a reel 9 with a tine bar at a position in front of the auger 8, and a clipper-shaped cutting blade 10 disposed longitudinally on the lower surface of the platform 7 on the left and right sides.

As shown in FIG. 3, the left traveling crawler 2a and the right traveling crawler 2b are hydraulic driving means of different systems.
It is driven separately by a hydraulic pump and one hydraulic motor.

That is, while power is transmitted from one engine 11 mounted on the traveling body 1 to the left and right hydraulic pumps 12a and 12b to drive them independently, the left hydraulic motor 13a is driven by the hydraulic pressure from the left hydraulic pump 12a. Then, the left traveling crawler 2a is separately driven by the left hydraulic motor 13a.

On the other hand, the right hydraulic motor 13b is driven by the right hydraulic pump 12b, and the right traveling crawler 2b is driven by the right hydraulic motor 13b.

Reference numerals 14a and 14b denote control valves for the hydraulic motors 13a and 13b, and control the hydraulic flow rate and the like for adjusting the swash plate angle in each of the hydraulic motors.
The rotation speeds and rotation directions of 13a and 13b are configured to be changeable in the forward and reverse directions.

Reference numerals 15a and 15b denote vehicle speed sensors for detecting the number of revolutions of the output shaft or traveling shaft 16 of the left and right hydraulic motors 13a and 13b.Each vehicle speed sensor brings an electromagnetic pickup close to a tooth surface that rotates integrally with the shaft. A sensor that detects the number of rotations from the periodic fluctuation of the magnetic field can be used.

Reference numeral 17 denotes one operating lever provided on a control unit on the traveling body 1, and the operating lever 17 is disposed in the front-rear direction (A-
(B direction) and the left and right direction (CD direction).

In one embodiment, as shown in FIG. 4, an open-top box 21 is attached to a front-rear shaft 20 provided between front and rear frames 18 and 19 so as to be rotatable only around the axis thereof. , The box
An operation lever 17 that rotates integrally with the horizontal shaft 22 is attached to a horizontal shaft 22 that is rotatably mounted on the left and right side plates 21a, 21a of the control device 21. A slider 24 is provided which comes into sliding contact with the surface of the arc-shaped resistor 23a of the vehicle speed potentiometer 23 having the axis of rotation as the center of rotation, and the sliding member protrudes from the outer surface of one of the front and rear side plates 21b of the box 21. The turning potentiometer 26 having the arc-shaped resistor 26a with which the moving element 25 makes sliding contact is fixed to the rear frame 19 or the like so that the front-rear shaft 20 is used as a center of rotation.

According to this configuration, the operation lever 17 is moved in the front-rear direction (A-
(B direction) rotated (inclined) at an appropriate angle (θ1),
It can be rotated (inclined) by an appropriate angle (θ2) in the left-right direction (CD direction), and can be tilted in the front-rear direction.
The resistance value R1 between the slider 24 and the terminal 28 of the resistor 23a changes in accordance with one angle, and a voltage signal is generated in accordance with the change. The resistance value R2 between the terminal 25 and the terminal 29 of the resistor 26a changes, and a signal of a voltage corresponding thereto is output.

As another embodiment, a vehicle speed potentiometer having an appropriate structure is fixed to the inner surface or the outer surface of one side plate 21a of the box 21, and the operation lever 17 is rotated in accordance with the rotation in the front-rear direction (AB direction). While a voltage signal corresponding to the relative angular position of the moving horizontal shaft 22 and the vehicle speed potentiometer is output, a turning potentiometer fixed to the front-rear shaft 20 and a box rotatable about the axis of the front-rear shaft 20 are provided. It may be configured to output a voltage of a magnitude corresponding to the relative rotation angle with the body 21.

Further, a push button type interlining turning switch 30 is provided at a hand grip portion of the operation lever 17, and the interlining turning switch is provided.
30 can be pressed with the thumb, and when the push button is first pressed, it is locked, and when pressed further, the lock is released and returned, and the pressed state (ON) and the unlocked state (OFF) are selected by alternate pressing action It has a configuration that can be held.

FIG. 5 is a diagram showing an input section and an output section for the central control device 31. The input interface section includes an interlining turning switch 30, the turning potentiometer, 26, a vehicle speed potentiometer 23, and switching of a switch to ON or OFF. Auxiliary shift switch 3 for reducing or increasing the vehicle speed at a fixed rate
2. The vehicle speed switch 33, which controls the rotational speeds of the left and right hydraulic motors according to a flowchart described later, and is turned on when executing control so that the vehicle speed becomes a predetermined value, the left and right vehicle speed sensors 15a, 15b, An automatic steering switch 34 which is turned ON when selecting to automatically steer the combine so as to be along the row of the cereal stem, a cutting selection switch 35 which selects a row cutting and a side cutting at the time of the automatic steering work, The right culm sensor 37, the left culm sensor 36R, the left outer culm sensor 36L, which detects the distance from the herbaceous plants on the left and right sides to the culms to be planted during the steering operation, and the rotation speed of the engine 11 are detected. The respective engine speed sensors 38 are connected.

The right culm sensor 37 is provided inside the right plant and detects the magnitude of the distance from the location to the row of planted cereal stems on the left side in four zones.
The zone closest to the zone is zone 0, and zones 1, zone 2, and zone 3 are set as the distance from the zone increases.

The left inner plant has a left inner grain sensor 36R on each side.
And a left outer culm sensor 36L, and a cereal culm located close to the inner side (right side) of the left plant is attached to the left inner culm sensor.
It is detected by 36R, and the culm located close to the outside (left side) of the left plant is detected by the left outer culm sensor 36L.

The control signal from the central control device 31 is to be output to the solenoids 40, 41 for the control valves 14a, 14b on both the left and right sides via the output interface unit, and the automatic steering switch 34 is turned on. ON of the automatic steering lamp 42 and the vehicle speed switch 33 that are lit when performing automatic steering control
Are connected to a vehicle speed lamp 43 that lights up when the vehicle speed control is being executed and a reverse buzzer 44 that sounds when the vehicle retreats.

Next, the mode of vehicle speed control will be described with reference to the flowcharts shown in FIGS.

FIG. 8 is the main flowchart, following the start,
In step S1, it is determined whether or not the vehicle speed switch 33 is ON. When the vehicle speed switch 33 is no (the vehicle speed switch 33 is OFF), a manual vehicle speed control subroutine is entered in step S2. This manual vehicle speed control subroutine changes the straight-line steering speed of the aircraft,
The rotation operation of the operation lever 17 can be arbitrarily performed by an operator, and is also a priority operation that can be interrupted and executed during vehicle speed control or automatic steering control described later.

In this manual vehicle speed control subroutine, the operator rotates and tilts the one operation lever 17 in the forward or rearward direction to thereby adjust the vehicle speed potentiometer according to the angle.
The target value of the vehicle speed is set by the output signal of 23, and the swash plate angles of both the left and right hydraulic motors 13a and 13b are set to the same predetermined value so that the target value is obtained, and the combine is set to the predetermined target value. The vehicle travels straight at the speed shown in FIG. Whether or not the current vehicle speed has reached the target value is detected by the vehicle speed sensors 15 and 15 and feedback control is performed.

In these cases, when the operating lever 17 is in the upright state, the rotational speeds of the left and right hydraulic motors are both zero (neutral position). The forward speed increases as θ1 increases. Similarly, when the operating lever 17 is tilted backward without tilting to the left and right sides, the traveling machine body 1 moves backward, and as the backward tilt angle of the operating lever increases, the retreat speed increases in proportion thereto.

When the operation lever 17 is rotated from the forward tilt (forward zone of the vehicle speed potentiometer) to the backward tilt (reverse zone of the vehicle speed potentiometer), and from the opposite forward tilt to the backward tilt, the neutral position (substantially vertical state) is set. If the vehicle passes through the position, the traveling speed is maintained at zero (approximately 1 second in the embodiment) for a suitable time (the neutral output value is maintained for a certain period of time) and then switched from forward to backward or backward to forward. To prevent damage to the mechanical mechanism and to eliminate the shock during the driving operation.

The operation lever 17 can also rotate (tilt) in the left-right direction, but when the left-right inclination angle (θ2) is within a predetermined small range (the output of the turning potentiometer 26 is in the straight traveling zone), it will be described later. Is a dead zone in which the so-called right and left turning is not executed.

FIG. 9 shows a manual vehicle speed control subroutine,
In Q1, it is determined whether or not the interlining turning switch 30 is turned on. When the answer is yes (the interlining turning switch 30 is turned on), the interlining turning vehicle speed control (step Q5) described later is executed, and no
When the interlining turning switch 30 is OFF, in the next step Q2, is the turning potentiometer 26 in the straight traveling zone (the left-right rotation (tilt) angle (θ2) of the operation lever 17 is within a predetermined small range)? Determine whether or not yes (in the straight ahead zone)
In the case of, the later-described straight traveling vehicle speed control (step Q3) is executed, and in the case of no (out of the range of the straight traveling zone), the later-described turning vehicle speed control (step Q4) is executed.

[Straight Vehicle Speed Control (Step Q3)] In this state, the interlining turning switch 30 is OFF, and the current vehicle speed at which the operator has released the operating lever 17 is maintained. In other words, the central control device drives both the left and right traveling crawlers 2a and 2b in the same direction, and drives the left and right hydraulic motors 13a and 13b in the same direction so that the traveling speeds of both the traveling crawlers 2a and 2b coincide with each other, and matches the rotation speeds. 31 to solenoid 4 of control valves 14a and 14b
Output signals having predetermined target values are sent to 0 and 41, respectively.

For example, with respect to the output value (SP) of the vehicle speed potentiometer 23 corresponding to the inclination angle of the operation lever 17, a proportional function f1 (SP) proportional to the output SP is set in a storage unit in the central control device 31 in advance. Alternatively, the right target value R of the output signal to be sent to the right control valve 14b is selected by the proportional function using the proportional function.
1 = f1 (SP) and the left target value of the output signal sent to the left control valve 14a
The central controller 31 calculates and outputs L1 = R1.

As described above, in the straight vehicle speed control, the vehicle moves forward or backward linearly while maintaining the target vehicle speed corresponding to the forward tilt (backward tilt) angle of the operation lever 17 manually moved by the operator.

[Turning Vehicle Speed Control (Step Q4)] In this control, the operator makes a right turn when the operator inclines the operation lever 17 forward or backward while tilting it to the right, and makes a left turn when inclining it to the left.

Then, both the left and right traveling crawlers 2a and 2b are driven in the same direction, and the deceleration ratio per unit time of the rotation speed of the hydraulic motor with respect to the traveling crawler inside the turning is determined by the ratio of the rotation speed of the hydraulic motor with respect to the traveling crawler outside the turning. Control is performed so as to be larger than the deceleration ratio per unit time.

As shown in FIG. 6 as the first embodiment, assuming that the rotation speed V1 of the hydraulic motor at the time of straight traveling immediately before the turn is, the rotation speed of the hydraulic motor corresponding to the traveling crawler on the outside of the turn is appropriately increased over time (T1). While continuously decelerating to V2, the rotational speed of the hydraulic motor corresponding to the traveling crawler inside the turn is continuously decelerated to V3 (V3 <V2 <V1) over an appropriate time (T2).

The turning vehicle speed control subroutine in this case is described in the tenth subroutine.
Shown in the figure.

For example, following the start of this subroutine, in step R1, when the operator tilts the operation lever 17 to the left as needed to make a left turn, the vehicle speed potentiometer corresponding to the front tilt angle of the operation lever 17 at the straight vehicle speed immediately before turning. Read the straight output value (SP) of 23.

Next, in step R2, the right control valve 14b corresponding to the outside of the turn
The right target value MR of the output signal to be sent to the left control valve 14a is calculated. In step R3, the left target value ML of the output signal to be sent to the left control valve 14a corresponding to the inside of the turn is calculated.

In this case, a proportional function f1 that is proportional to the output
While calculating (SP), the output value (TP) of the turning potentiometer 26 corresponding to the horizontal inclination angle of the operation lever 17
And the comparison function f2 (TP) proportional to this output value TP
And f5 (TP) are calculated, and the right target value MR = f2 (TP) × f1 (SP) of the output signal to be sent to the right control valve 14b corresponding to the outside of the turn is calculated by these proportional functions. The left target value ML of the output signal sent to the corresponding left control valve 14a = MR × f5 (T
P) is calculated by the central controller 31.

Next, in step R4, the time required to decelerate the rotational speeds of the left and right hydraulic motors to the respective target values (target arrival time) is calculated. Here, T1 is the right target achievement time, and T2 is the left target achievement time.

This target achievement time is set to be longer when the difference between the output value SP at the time of straight traveling immediately before turning and the right or left target value MR or ML at turning is large, and is shortened when the difference is small. Is used to calculate the target arrival time.

In step R5, a right output ratio ΔVR corresponding to the deceleration ratio of the rotation speed of the right hydraulic motor per unit time is calculated, and in step R6, the left output corresponding to the deceleration ratio of the rotation speed of the left hydraulic motor per unit time is calculated. Calculate the ratio ΔVL.

The deceleration ratio (output ratio) per unit time may be one that realizes a constant so-called linear deceleration state irrespective of elapse of time, or deceleration at the line start side with elapse of time. The deceleration ratio (output ratio) may be set to be smaller as the ratio (output ratio) is larger and approaches the target value. In any case, the unit time of the number of rotations of the hydraulic motor for the traveling crawler inside the turn is set. The deceleration ratio per hit is set to be larger than the deceleration ratio per unit time of the rotation speed of the hydraulic motor with respect to the traveling crawler outside the turning.

Next, in step R7, an output value corresponding to the rotational speed of the right hydraulic motor at the present time during turning (right current output value = GR)
Is read, and in step R8, the left current output value = GL corresponding to the rotation speed of the left hydraulic motor is read.

In step R9, the right current output value (GR) becomes the right target value (MR)
If GR> MR (yes), a right deceleration control is executed in step R10 in accordance with the right output ratio ΔVR. If no, the rotational speed of the right hydraulic motor is set to the target. Since the vehicle is decelerating to the value, do not perform any further deceleration (the current status is maintained), and in step R11, determine whether the left current output value (GL) is larger than the right target value (ML),
If GL> ML (yes), a left deceleration control is executed in step R12 according to the left output ratio ΔVL. When no, the rotational speed of the left hydraulic motor is also decelerating to a predetermined target value, so the current position is set. After executing Step R12, the process returns to Step R7, and the control after Step R7 is repeated thereafter.

Further, as can be understood from these functional relationships, when the turning radius is small, that is, as the inclination angle θ2 of the operation lever 17 to the right or left is larger, the traveling crawler speeds on the left and right sides are further reduced. Therefore, the running stability when making a small turn is not impaired.

If the turning direction is opposite to the above, the relationship between the right and left target values of the output signal is reversed.

When the turning direction of the operation lever 17 is switched from left to right or right to left, the turning control in the opposite direction is not performed immediately, but is performed for an appropriate time (0, 5 in the embodiment).
Second) The output value of the straight-ahead vehicle speed control is output once to ensure safe operation.

FIG. 7 shows a second embodiment [turning vehicle speed control ']. As shown in FIG.
When 1 ′ is set, the rotation speed of the hydraulic motor corresponding to the traveling crawler on the outer side of the turning is changed to V2 ′ + Δα over an appropriate time (T1 ′).
V, while the rotational speed of the hydraulic motor corresponding to the traveling crawler inside the turn was continuously reduced to V3 '+ ΔβV (V3' + ΔβV <V2 '+ ΔαV) over an appropriate time (T2 ′). Later, on the outside of the turn, ΔT1 ′ (T ′> Δ
T1 ') and gradually decelerates to V2' (pulse-like), and also inside ΔT2 '(T2'> ΔT2 ')
It decelerates stepwise (pulse-like) to V3 '.

The subroutine of the turning vehicle speed control 'in this case is substantially the same as that described above.

In this case, the time required to decelerate the rotational speeds of the left and right hydraulic motors to the respective target values (target arrival time = T1 ′ and ΔT
1′T2 ′, ΔT2 ′) is set to be longer when the difference between the output value SP during straight ahead immediately before turning and the right or left target value MR, ML during turning is large, and to be shorter when the difference is small. The target arrival time is calculated using a predetermined proportional function.

Further, the deceleration ratio of the section where the vehicle is continuously decelerated and the rate of decrease per unit time of each stage of the section where the vehicle is gradually decelerated realize a constant, so-called linear deceleration state regardless of the passage of time. The deceleration ratio may be set so that the deceleration ratio increases at the start of turning with time and decreases as the speed approaches the target value. The deceleration ratio of the rotation speed of the motor per unit time is set to be larger than the deceleration ratio of the rotation speed of the hydraulic motor per unit time to the traveling crawler outside the turning.

When returning to the straight vehicle speed control from the turning vehicle speed control, the vehicle speed is maintained at a half of the sum of the vehicle speeds on the inside and outside of the turning for an appropriate time, and then set to a predetermined straight vehicle speed.

[Interlining Turning Control (Step Q5)] In this control, if the operation lever 17 is tilted right or left while turning on the interlining turning switch 30, so-called interlining turning is performed. In this case, Control lever 17
In the forward tilt state, the interlining turns when the vehicle is moving forward, and when the operation lever 17 is tilted rearward, the interlining turning when the vehicle retreats is executed.

For example, when the operation lever 17 is appropriately inclined rightward in the forward inclined state, the right and left hydraulic motors mutually move so that the right traveling crawler 2 on the turning inner diameter side moves backward and the left traveling crawler 2 on the turning outside moves forward. Rotate forward and backward.

Conversely, when the vehicle is inclined leftward in the forward inclined state, the left and right hydraulic motors rotate forward and reverse to each other so that the left traveling crawler 2 on the turning inner diameter side moves backward and the right traveling crawler 2 on the turning outside moves forward. .

In this case, both the left and right hydraulic motors 13a, 2b drive the left and right traveling crawlers 2a, 2b in directions opposite to each other, and reduce the traveling speed of the both traveling crawlers to approximately 1/4 of the speed when traveling straight. In order to reduce the rotation direction and the rotation speed of the control valve 13b, the central control device 31 controls the solenoids 4 of the control valves 14a and 14b.
A predetermined output signal is sent to each of 0 and 41.

For example, when the operator presses the interlining turning switch 30 and tilts the operation lever 17 to the left side as appropriate to turn the interlining in the left direction, the vehicle speed potentiometer 23 corresponding to the inclination angle of the operation lever 17 at the straight running vehicle speed is used. Output value (S
P), a proportional function f1 (SP) proportional to the output SP is calculated. On the other hand, when the output value (TP) of the turning potentiometer 26 corresponding to the inclination angle of the operation lever 17 in the left-right direction is calculated, this output A proportional function f4 (TP) proportional to TP is calculated and obtained, and the right target value MR of the output signal to be sent to the right control valve 14b corresponding to the outside of the turn is calculated by these proportional functions MR = f4 (TP) × f1
The central controller 31 calculates and outputs (SP) and the left target value ML = −MR of the output signal sent to the left control valve 14a corresponding to the inside of the turn.

When the inclination angle of the operation lever 17 to the left and right becomes large, the degree of the deceleration is set to be large.

When the interlining turning switch 30 is changed from ON to OFF, the vehicle speed at the time of the interlining turning switch 30 is turned off.
An intermediate speed obtained by adding the vehicle speed at the time of F and dividing by 2 is maintained for an appropriate period of time (about 6/10 seconds in the embodiment), and then controlled to be the vehicle speed at the time of OFF.

Also, when the interlining turning switch 30 is turned on,
When the operation lever 17 is not tilted left and right, the speed of the left and right traveling crawlers 2, 2 is greatly reduced to about 1/4 of that at the time of straight traveling, and the vehicle travels straight.

In each of the manual vehicle speed controls, when the sub-transmission switch 32 is turned on, the speed can be reduced to, for example, approximately half of the speed in the case of being turned off.

In step S1 of FIG. 8, yes (vehicle speed switch 3
When it is determined that 3 is ON), a vehicle speed control subroutine is entered (step S3).

FIG. 11 shows a vehicle speed control subroutine, in which the output value of the vehicle speed potentiometer 23 has changed in step P1 (in other words, whether the forward-backward rotation (tilt) angle of the operating lever 17 has changed due to the operation of the worker). It is determined whether or not.

When it is determined as yes in Step P1, the manual vehicle speed subroutine is executed to prioritize the result of the rotation operation (manual) of the operation lever 17 (Step P2).

If no (no change in the forward / backward rotation (inclination) angle of the operation lever 17) in step P1, it is determined in step P3 whether the interlining turning switch 30 is ON or not.
When s (the interlining turning switch 30 is ON), the interlining turning vehicle speed control described later (step P4) is executed, and when no (the interlining turning switch 30 is OFF), the turning potentiometer 26 is turned on in the next step P5. Is determined to be within the straight traveling zone (the left-right rotation (tilt) angle (θ2) of the operation lever 17 is within a predetermined small range). Perform step P6) and no
If it is (out of the straight traveling zone range), the later-described turning vehicle speed control (step P7) is executed.

[Straight Vehicle Speed Control (Step P6)] In this state, the interlining turning switch 30 is OFF, and the current vehicle speed at which the operator has released the operating lever 17 is maintained.

In the vehicle speed control, the output (load) of the engine 11 is detected by an electronic governor (not shown), and when the load has a surplus, the fuel supply amount (injection amount) is increased and a predetermined output (for example, The engine speed is also increased to achieve the rated output. As a result, the rotation speeds of the left and right hydraulic pumps and, consequently, the rotation speeds of the respective hydraulic motors are also increased. On the other hand, when a large load is applied to the engine, the vehicle speed control is performed such that the engine speed is reduced to a predetermined load (output) and the speed of each of the hydraulic motors is reduced.

In this case, since the straight running control is used,
The central control device 31 controls the left and right hydraulic motors 13a, 13b in the same direction so that the traveling speeds of the two motors 2a, 2b are the same, and the rotational speeds of the two hydraulic motors 13a, 13b are the same.
An output signal having a predetermined target value is sent to each of the solenoids 40 and 41 of 14a and 14b.

The target value is determined from the current engine load state, and a function f6 (engine load) related to the engine load is determined by using a map or a function table previously set in a storage unit in the central control device 31. Right target value MR of output signal selected and sent to right control valve 14b = f6 (current engine load)
And the central control device 31 calculates and outputs the left target value ML = MR of the output signal sent to the left control valve 14a.

[Turning Vehicle Speed Control (Step P7)] In this control, the operator turns right when the operator inclines the operation lever 17 to the right, and turns left when the operator inclines the operation lever 17 to the left. And
The speed at the time of turning is set so as to be reduced to about 1/2 of the current vehicle speed (a vehicle speed that optimizes the engine load) forward speed V3 or the like.

That is, both the left and right traveling crawlers 2a and 2b are driven in the same direction, and the traveling speed of the traveling crawler outside the turning is reduced to about 1/2 of the speed at the time of straight traveling, and the speed of the traveling crawler inside the turning is simultaneously reduced. In order to further reduce the rotational speeds of the left and right hydraulic motors 13a, 13b so as to further reduce the speed outside the turning outside, the central control device 31 sends control valves 14a, 14b.
An output signal having a predetermined target value is sent to each of the solenoids 40 and 41.

In this case, while calculating the function f6 (current engine load) related to the current engine load, the output value (TP) of the turning potentiometer 26 corresponding to the inclination angle of the operation lever 17 in the left-right direction is obtained. Compute and calculate comparison functions f7 (TP) and f8 (TP) proportional to TP, and use these comparison functions to calculate the right target value MR = f7 (TP) of the output signal sent to the right control valve 14b corresponding to the outside of the turn. × f6 and the left target value ML of the output signal sent to the left control valve 14a corresponding to the inside of the turn ML = MR × f8
(TP) is calculated and output by the central control device 31.

The proportional function f8 (TP) is set to further reduce the speed inside the turn than the speed outside the turn.

When the turning direction of the operation lever 17 is switched from left to right or right to left, the turning control in the opposite direction is not performed immediately, but is performed for an appropriate time (0, 5 in the embodiment).
Second) The output value of the straight-ahead vehicle speed control is output once to ensure safe operation.

[Centering Turning Control (Step P4)] In this control, if the operating lever 17 is tilted to the right or left while the turning center turning switch 30 is turned on, so-called interlining turning is executed.

For example, when the operator presses the interlining turning switch 30 and tilts the operation lever 17 to the left side as needed to turn the interlining in the leftward direction, the function f6 related to the engine load in the straight traveling state is calculated. Assuming that the output value (TP) of the turning potentiometer 26 corresponding to the inclination angle of the operation lever 17 in the left-right direction is a proportional function f9 proportional to this output TP
(TP) is calculated and these functions are used to calculate the right target value MR = f of the output signal sent to the right control valve 14b corresponding to the outside of the turn.
The central control unit 31 calculates and outputs 6 × f9 (TP) and the left target value ML = −MR of the output signal sent to the left control valve 14a corresponding to the inside of the turn.

As a result, a predetermined output signal is sent from the central control device 31 to each of the solenoids 40 and 41 of the control valves 14a and 14b to retreat the right traveling crawler 2 on the turning inner diameter side and advance the left traveling crawler 2 outside the turning. The left and right hydraulic motors rotate forward and reverse to each other, and the traveling speed of both traveling crawlers,
The rotational directions and the rotational speeds of both the left and right hydraulic motors 13a and 13b are reduced so that the speed is reduced to approximately 1/4 of the speed at the time of the straight traveling.

It is preferable to set the function so as to increase the degree of deceleration when the inclination angle of the operation lever 17 to the left and right increases.

When the interlining turning switch 30 is changed from ON to OFF, an intermediate speed obtained by adding the vehicle speed when the interlining turning switch 30 is ON to the vehicle speed at the time of OFF and dividing by 2 is appropriately set (for example, in the embodiment). After about 6/10 seconds), control the vehicle speed to the OFF speed.

In each of the above-described controls, when the sub-transmission switch 32 is turned on, the speed can be reduced, for example, to approximately half of the speed in the case of being turned off.

If the automatic steering switch 34 is turned on, the left culm sensors 36R and 36L and the right culm sensor 37 provided on the left and right both sides of the weeding pretreatment device 4 of the combine 1 are used to plant the field scene. The cutting and threshing operation is performed while detecting the distance to the standing culm row and steering along the culm row. A flowchart of this automatic steering is shown in FIG.

The steering in this case is also controlled by the central control device 31 from the control valves 14a and 14b.
An output signal having a predetermined target value is sent to each of the solenoids 40 and 41, the rotational speeds of both the left and right hydraulic motors 13a and 13b are changed, and the speed is changed by changing the speed of the left and right traveling crawlers 2a and 2b. I have.

In this case, the steering control is released when the operation lever 17 is tilted backward (reverse zone), when the operation lever is tilted left and right to turn (turn zone), or when the interlining turning switch 30 is ON. Is done.

Table 1 shows that the right culm sensor 37, the left inner culm sensor 36R during each of the vertical cutting and the side cutting in the steering control,
The steering operation of the traveling body by detection of the left outer culm sensor 36L is shown.

In Table 1, the zone history refers to the detection result immediately before the latest detection result when the zone detection by the right culm sensor 37 is executed at appropriate time intervals.

The place where the zone history in the vertical cutting state is (-) mark,
The meaning of deciding the operation ignoring the results of zone history is that the (*) mark of the detection result of the left culm sensor is ON, OF
F means that it may be either.

Also, when both the left inner grain culm sensor 36R and the left outer grain culm sensor 36L are ON, the left plant is moving so as to break the planted grain culm, so that it does not dare to turn left or right.

In the side-cutting state, when the zone history is any one of 0, 1, 2, and 3 and the latest detection result of the right cereal culm sensor 37 is “3”, that is, the zone is 0, 1, 2, 3 When → 3, the planted culm is located farther to the right than the right weeding body, while the traveling body is moving away from the rightmost planted culm, considering the zone history. Is turned to the right to increase grain culm uptake by the pre-cutting device 4, and the zone history is either 0 or 1, and the detection result of the latest right grain culm sensor 37 is "1". At a certain time, that is, when the zone changes from 0,1 to 1, the planted cereal stem is located close to the right side of the right weeding body, while the running aircraft approaches the rightmost planted cereal stem at the right end of the zone history. The running aircraft is turned to the left so that there is no remaining mowing.

In addition, when the zone history is 0, 1, 2 → 2, and when 0 → 0, the vehicle does not turn unnecessarily as straight traveling. In other zone histories, the previous operating state is continued.

[Brief description of the drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a plan view of a combine, FIG. 2 is a side view, FIG. 3 is a schematic diagram of a drive transmission system of a traveling crawler, FIG. 5 is a block diagram of a control circuit, and FIG. 6 is a first diagram of turning vehicle speed control.
FIG. 7 is a diagram showing a change in the number of revolutions of the hydraulic motor in the embodiment, FIG. 7 is a diagram showing a change in the number of revolutions of the hydraulic motor in the turning vehicle speed control, and FIGS. 8, 9, 10, 11, and 12 are Each is a flowchart. DESCRIPTION OF SYMBOLS 1 ... Traveling body, 2a, 2b ... Traveling crawler, 3 ... Threshing device, 4 ... Cutting pretreatment device, 5 ... Feeder house, 7 ... Platform, 8 ... Scrape auger, 9
... reel, 11 ... engine, 12a, 12b ... hydraulic pump, 13a, 13b ... hydraulic motor, 14a, 14b ... control valve, 17 ...
… Operation lever, 23… Vehicle speed potentiometer, 26 …… Turn potentiometer, 30 …… Intersection turn switch, 31 ……
Central control unit.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) A01B 69/00-69/08 E02F 9/22 B62D 11/04

Claims (1)

(57) [Claims] A power transmission device configured to transmit power to a pair of left and right traveling crawlers of a traveling work machine by left and right separate hydraulic driving means including a hydraulic pump and a hydraulic motor; In the traveling work machine configured to control the rotation speed of the hydraulic motor outside the turn at the time of turning the deceleration ratio per unit time,
A steering control device for a traveling work machine, wherein the steering control device performs control so as to increase a deceleration ratio per unit time of a rotation speed of a hydraulic motor inside a turn.