JP2974075B2 - 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 operation and each flow control valve for controlling the rotation speed of the left and right hydraulic motors,
An electric control circuit is provided, and a turning command signal from the detection device is given to the flow control valve to control each of the rotation speeds of the hydraulic motors for the left and right traveling crawlers to be changed, and there is no signal from the detection device. Sometimes, a straight-ahead command signal is given to the flow control valve to control the body to go straight. In this control, a so-called unmanned automatic steering system is used.
This was applied when steering.

However, in the related art, when the operator performs the steering / running operation while riding on the airframe, the left and right turning is performed by separate left and right clutches or operating to reduce or stop the rotation speed of the right or left traveling crawler inside the turning. It is necessary to operate the lever, and in the case of a clutch, both feet must be used, and in the case of an operation lever, both hands must be used, which is troublesome.

In addition, when the rotation speed of the traveling crawler on the outer side of the turning is the same as that in the straight traveling state, the turning is rapid, and there is a problem that the safety is lacking.

To solve this problem, Japanese Unexamined Utility Model Publication No. Sho 61-133470 discloses a mono-lever-type command signal generating means that uses a single operating lever from the origin of the coordinates to specify a coordinate position designated by operating one operating lever. It is disclosed that the speed of the traveling crawler is separately controlled. However, in this technique, for example, by operating an operation lever for turning forward and right, the left traveling crawler on the outer side of the turn adds a predetermined speed to the speed at the time of going straight, while the right traveling crawler on the inside of the turn advances at the predetermined speed. Therefore, the traveling speed on the outside of the turn is accelerated from the time of forward movement, so that the turn tends to be sharp, and a large centrifugal force acts on the operator mounted on the traveling work machine, so that the operator is easily swung. was there.

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

[Means for solving the problem]

Therefore, the steering control device in the traveling work machine according to the present invention is configured to transmit power to the pair of left and right traveling crawlers in the traveling work machine by left and right separate hydraulic driving means including a hydraulic pump and a hydraulic motor. And a traveling work machine comprising control means for controlling the number of rotations and the direction of rotation of the left and right hydraulic motors, wherein a control means for executing a turning operation by operating one operating tool provided on the traveling work machine is provided. When turning, the control means decelerates both the left and right traveling crawlers at a fixed rate from the speed at which the vehicle travels straight back and forth, and further controls the traveling crawlers inside the turning further.

〔The invention's effect〕

As described above, according to the present invention, since the traveling work machine can be turned left and right by one operation of the turning tool, the manual operation is significantly simplified as compared with the conventional case of operating a plurality of turning operation levers separately. Is done.

Then, when turning by operating the one operating tool from the forward or backward straight traveling state at an appropriate speed, the control means reduces the speeds of the left and right traveling crawlers of the traveling work machine at a fixed rate from the speed at the time of traveling straight. In addition, since automatic control is performed to reduce the speed of the traveling crawler inside the turn, the centrifugal force acting on the operator is not so large when moving from straight running to turning, making it possible to perform extremely safe turning work easily. It has the remarkable effect of being able to do it.

〔Example〕

Next, embodiments of the present invention will be described. Reference numeral 1 denotes a traveling body of a general-purpose combine having a pair of right and left traveling crawlers 2a and 2b, on which a threshing device 3 is mounted. It is arranged along the traveling direction of the fuselage 1, and below it is provided a swing sorting device using a receiving net and a sheave and a wind sorting device using the wind of Karin 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 pump 13b drives the right hydraulic motor 13b, and the right hydraulic motor 13b drives the right traveling crawler 2b.

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 tilt angle of each hydraulic motor, thereby controlling each hydraulic motor.
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 of each of the left and right hydraulic motors 13 or the traveling shaft 16, and each vehicle speed sensor brings an electromagnetic pickup close to a tooth surface which rotates integrally with the shaft and generates a magnetic field. For example, a sensor that detects the number of rotations from the periodic fluctuation of the rotation speed can be used.

Reference numeral 17 denotes one operation lever as one operation tool provided on a control unit on the traveling body 1. The operation lever 17 is provided in the front-rear direction (A-B direction) and the left-right direction (C- D direction).

As shown in FIGS. 4 to 6, one embodiment of the present invention is an open-top box that is rotatable only about its axis with respect to a front-rear shaft 20 provided between the front and rear frames 18, 19. An operation lever 17 that rotates integrally with the horizontal axis 22 is attached to a horizontal axis 22 that is mounted on the left and right side plates 21a and 21a of the box 21 and that is mounted on the horizontal axis 22. At the lower end of 17 is provided a slider 24 that comes into sliding contact with the surface of an arc-shaped resistor 23a of a vehicle speed potentiometer 23 with the axis of the horizontal shaft 22 as the center of rotation, and one of the front and rear side plates of the box 21 is provided. A turning potentiometer 26 having an arc-shaped resistor 26a in which a slider 25 protruding from the outer surface of the side plate 21b comes into sliding contact is fixed to the rear frame 19 or the like so that the front-rear shaft 20 is the center of rotation. is there.

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 the terminals 2 on the slider 24 and the resistor 23a are changed according to the inclination θ1 angle in the front-rear direction.
The resistance value R1 changes between 8 and 8 and a signal of a potential (voltage) corresponding to the change is generated, and the distance between the slider 25 and the terminal 29 of the resistor 26a is changed according to the inclination θ2 angle in the left-right direction. The resistance value R2 changes, and a signal of a potential (voltage) corresponding to the change 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). A rotating potentiometer fixed to the front-rear shaft 20 and a turning potentiometer fixed to the front-rear shaft 20 so as to be rotatable around the axis of the front-rear shaft 20 while outputting a signal having a different potential according to the relative angular position between the moving horizontal shaft 22 and the vehicle speed potentiometer It may be configured to output different potentials depending on the relative rotation angle with the simple box 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. 7 is a diagram showing an input section and an output section for a central control device 31 as control means for executing steering control. The input interface section includes an interlining turning switch 30, the turning potentiometer 26, and a vehicle speed potentiometer 23. A sub-transmission switch 32 for decelerating or increasing the vehicle speed at a constant ratio by switching the switch to ON or OFF, controlling the rotational speeds of the left and right hydraulic motors according to a flowchart described below, so that the vehicle speed becomes a predetermined value. The vehicle speed switch 33 and the left and right vehicle speed sensors 15a, 15
b, an automatic steering switch 34 that is turned on when selecting automatic steering of the combine so as to be along the row of planted grain culms, selecting cutting and side cutting during the automatic steering operation. Cutting selection sensor 35, left culm sensor 36 and right culm sensor 37 for detecting the distance to the row of planted cereals on the left side during this automatic steering operation, engine speed for detecting the rotation speed of engine 11 Each of the sensors 38 is connected.

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
Car speed ramp when running car speed control at
43 and a reverse buzzer 44 that sounds at the time of retreat are connected respectively.

Next, the mode of vehicle speed control and steering 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. If 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 allows the operator to arbitrarily execute the change of the straight running speed of the aircraft by rotating the operation lever 17, and interrupts the vehicle speed control and automatic steering control described later. It is also a priority operation that can be executed with.

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, 15b, 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). As θ1 increases, the forward speed increases. Similarly, when the operating lever 17 is tilted backward without tilting to the left and right sides, the traveling body 1 retreats. As the operating lever backward tilt angle increases, the reverse speed also increases in proportion. growing.

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 relationship 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-ahead vehicle speed control, the vehicle moves forward or backward while maintaining the target 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 turns right when the operator tilts the operation lever 17 forward or backward while tilting it to the right, and turns left when tilting it to the left. Then, the speed at the time of turning is determined by the forward speed V1 or the reverse speed corresponding to the inclination angle of the operation lever.
It is set to decelerate to about 1/2 of V2.

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.

For example, when the operator appropriately tilts the operation lever 17 to the left to turn left, a vehicle speed potentiometer corresponding to the inclination angle of the operation lever 17 at the straight-ahead vehicle speed.
For the output value (SP) of 23, a proportional function f1 (SP) that is proportional to the output SP is calculated (it may already be obtained), while it corresponds to the inclination angle of the operation lever 17 in the left-right direction. When the output value (TP) of the turning potentiometer 26 is
The proportional functions f2 (TP) and f5 (TP) proportional to the output TP are calculated and obtained, and by these proportional functions, the right target value R2 = f2 (of the output signal sent to the right control valve 14b corresponding to the outside of the turn. T
The central controller 31 calculates and outputs P) × f1 (SP) and the left target value L2 = R2 × f5 (TP) of the output signal sent to the left control valve 14a corresponding to the inside of the turn.

In this case, the proportional function f5 (TP) is set to further reduce the speed inside the turn than the speed outside the turn. Also, as can be understood from these functional relationships,
When the turning radius is small, that is, as the inclination angle θ2 of the operating lever 17 to the right or left is larger, the traveling crawlers on the left and right sides are further reduced in speed, so that the traveling stability when making a small turn is not impaired. Like that.

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.

[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, the speeds of the left and right traveling crawlers 2, 2 are greatly reduced to about 1/4 of the straight traveling.

That is, the left and right hydraulic motors 13a, 13b are driven so that the left and right traveling crawlers 2a, 2b are driven in opposite directions to each other, and the traveling speed of both traveling crawlers is reduced to about 1/4 of the straight traveling speed. In order to reduce the rotation direction and the number of rotations, respectively, the central control device 31 sends the solenoids 40, 14a, 14b of the control valves 14a, 14b.
An output signal having a predetermined target value is sent to 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 (it may already be obtained), while the output of the turning potentiometer 26 corresponding to the inclination angle of the operation lever 17 in the left-right direction is calculated. When the value is (TP), a proportional function f4 (TP) proportional to the output TP is calculated and obtained. By using these proportional functions, the right target value R3 of the output signal to be sent to the right control valve 14b corresponding to the outside of the turn is obtained. = F4 (TP) x f1 (SP) and the left target value L3 of the output signal sent to the left control valve 14a corresponding to the inside of the turn =
The central controller 31 calculates and outputs −R3.

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. 10 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 (step P4) described below is executed, and when no (the interlining turning switch 30 is OFF), the turning potentiometer is used in the next step P5. 26 is in the straight ahead zone (operating lever 17
(Left / right rotation (tilt) angle (θ2) is within a predetermined small range)
Is determined (yes (in the straight running zone), the straight running vehicle speed control described later (step P6), and
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 the function f6 (engine load) related to the engine load is determined by a map or a function table previously set in a storage unit in the central control device 31. Right target value R4 of the output signal selected and sent to the right control valve 14b = f6 (current engine load)
The central control device 31 calculates and outputs the left target value L4 = R4 of the output signal sent to the left control valve 14a.

[Turning Vehicle Speed Control (Step P7)] In this control, the operator makes a right turn when the operator inclines the operation lever 17 to the right, and makes a left turn 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. Calculate and calculate proportional functions f7 (TP) and f8 (TP) proportional to TP, and use these proportional functions to calculate the right target value R5 = 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 L5 of the output signal sent to the left control valve 14a corresponding to the inside of the turn L5 = R5 × f8
(TP) is calculated and output by the central control device 31.

In this case, the proportional function f8 (TP) is set to further reduce the speed inside the turn than the speed outside the turn. Also, as can be understood from these functional relationships,
When the turning radius is small, that is, as the inclination angle θ2 of the operating lever 17 to the right or left is larger, the traveling crawlers on the left and right sides are further reduced in speed, so that the traveling stability when making a small turn is not impaired. Like that.

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.

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

For example, when the operation lever 17 is tilted to the right as appropriate, the right and left hydraulic motors rotate forward and backward 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.

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, the speeds of the left and right traveling crawlers 2, 2 are greatly reduced to about 1/4 of the straight traveling.

In other words, both the left and right hydraulic motors 13a, 2b drive the left and right traveling crawlers 2a, 2b in opposite directions, and reduce the traveling speed of both traveling crawlers to approximately 1/4 of the speed at the time of straight traveling. An output signal having a predetermined target value is sent from the central control device 31 to the solenoids 40, 41 of the control valves 14a, 14b in order to decrease the rotation direction and the rotation speed of the 13b, respectively.

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 left direction, a function f6 related to the engine load in the current straight traveling state is calculated ( On the other hand, when the output value (TP) of the turning potentiometer 26 corresponding to the inclination angle of the operating lever 17 in the left-right direction is calculated, a proportional function f9 (TP) proportional to this output TP is calculated. From these functions, the right target value R6 of the output signal to be sent to the right control valve 14b corresponding to the outside of the turn is calculated by these functions as R6 = f6 × f9 (TP),
The central control device 31 calculates and outputs the left target value L6 = -R6 of the output signal sent to the left control valve 14a corresponding to the inside of the turn.

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.

When the automatic steering switch 34 is turned ON, the left culm sensor 36 and the right culm sensor 37 provided on the left and right both-sided weeds of the harvesting pre-processing device 4 of the combine 1 are used to set up the planted crop in the field scene. FIG. 11 shows a flowchart of automatic steering in which the cutting and threshing work is executed while steering along the grain culm row while detecting the perspective distance to the culm row.

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 make a turn (turn zone), or when the interlining turn switch 30 is turned on. Is done.

[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 side view, FIG. 6 is a plan view, FIG. 7 is a block diagram of a control circuit, and FIGS. 8 to 11 are flowcharts. DESCRIPTION OF SYMBOLS 1 ... Traveling body, 2a, 2b ... Traveling crawler, 3 ... Threshing device, 4 ... Cutting pre-processing 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.

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; And a control device for controlling a rotation direction, the control device for performing a turning operation by operating one of the operating tools provided on the driving work device, the control device includes: A steering control device for a traveling work machine, wherein the left and right traveling crawlers are decelerated at a fixed rate from the speed at the time of straight traveling, and the traveling crawlers inside the turning are further decelerated.