JPH10164924A - Traveling vehicle for working - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a traveling vehicle for working which reduces operation labor and maintaining a traveling machine body to be in a stable posture for improving working precision by providing an automatic brake control means, etc., automatically braking the rotation of a prescribed wheel body so as to stabilize the posture of the machine body. SOLUTION: This traveling vehicle for working is provided with a tilting sensor 8 detecting the tilting of the traveling machine body, a machine body posture judging means judging the posture of the machine body based on the detection signal of this sensor 8 and the automatic brake controlling means automatically braking the rotation of prescribed wheel bodies 4 and 5 to stabilize the posture of the machine body when the traveling machine body is tilted. In addition, it is desirable to provided the traveling vehicle with an acceleration sensor 9 to detect the rapid posture change of the traveling machine body, a power distribution mechanism changing the distribution of power to be transmitted to the front and rear wheels 4 and 5, and an automatic power distribution control means automatically changing the distribution of the power to be transmitted to the front and rear wheels 4 and 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of working vehicles such as riding rice transplanters.

[0002]

2. Description of the Related Art Generally, in a working vehicle of this type, when an operator operates a traveling machine, an accelerator operating mechanism for changing an engine speed based on an operation of an accelerator lever (or an accelerator pedal), and a clutch. A traveling clutch operating mechanism that intermits power transmission to wheels based on pedal operation, a traveling shift operating mechanism that shifts power to wheels based on operation of a traveling shift lever, and a rotation of wheels based on operation of a brake pedal. It is required to operate a traveling system operation mechanism such as a brake operation mechanism for braking in a complex manner.

[0003]

By the way, the above-mentioned running operation can be performed with a margin on a flat ground where the body posture is relatively stable, but the operation on a slope on which the body posture tends to become unstable is easy. In some cases, prompt operation by the operator is required in some cases, so that the operation labor is actually increased, and when the traveling body cannot be maintained in a stable posture, the work accuracy is reduced. was there.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has been made with the object of providing a working vehicle capable of solving these problems. A work vehicle having a brake mechanism for braking the rotation of a wheel on a traveling body traveling with rotation, wherein the work vehicle has an inclination sensor for detecting an inclination of the traveling body, Body attitude determining means for determining the body attitude based on the detection signal of the tilt sensor, and automatic brake control means for automatically braking the rotation of a predetermined wheel body to stabilize the body attitude when the traveling body is inclined, Is provided. In other words, when the traveling machine body tilts, the rotation of the predetermined wheel body is automatically braked to stabilize the machine body attitude. Accuracy can be improved.

[0005] In addition, a working vehicle having a brake mechanism for braking the rotation of the wheel is provided on a running machine that travels with the rotation of the wheel. An acceleration sensor that detects a sudden change in attitude, a body attitude determination unit that determines a sudden change in the attitude of the traveling body based on a detection signal of the acceleration sensor, and a predetermined wheel body when the body attitude changes abruptly. And automatic brake control means for automatically braking the rotation to stabilize the attitude of the aircraft. In other words, when the attitude of the aircraft suddenly changes, the rotation of the predetermined wheel is automatically braked to stabilize the attitude of the aircraft. Work accuracy can be improved.

Further, in the above-mentioned apparatus, the power distribution mechanism for changing the distribution of the power transmitted to the front and rear wheels, and automatically changing the distribution of the power transmitted to the front and rear wheels when the attitude of the body changes. And automatic power distribution control means for stabilizing the attitude of the aircraft. In other words, when the attitude of the body changes, not only the rotation of the predetermined wheel is automatically braked, but also the distribution of the power transmitted to the front and rear wheels is automatically changed to stabilize the attitude of the body. Not only is it not possible to reduce the labor, but also it is possible to maintain the running body in a stable posture and improve the working accuracy.

[0007]

Next, one embodiment of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a traveling machine of a riding rice transplanter, and the traveling machine 1 uses a main clutch mechanism 3 to drive the power of an engine 2 mounted on the front side of the machine.
The transmission power is transmitted to the front wheels 4 and the rear wheels 5 via a traveling speed change mechanism (not shown), and the shifted power is transmitted to a stock change mechanism (not shown) and a planting clutch mechanism (not shown).
, And transmitted to the planting work section P at the rear of the machine body, and these basic configurations are all conventional.

[0008] The main clutch mechanism 3 includes a traveling machine 1
The intermittent operation is performed based on the operation of a clutch pedal (not shown) provided in the operation section of the multi-plate hydraulic clutch mechanism to control the power transmission rate in accordance with the hydraulic pressure supplied on a separate path from the clutch pedal. Has been adopted.

Reference numeral 6 denotes a center differential mechanism provided at a power transmission branch point between the front and rear wheels 4 and 5, and the center differential mechanism 6 uses a torque split type differential mechanism or the like having a multi-plate hydraulic clutch mechanism therein. It is configured.
That is, by controlling the power transmission rate of the multi-plate hydraulic clutch mechanism, the distribution of the power transmitted to the front and rear wheels 4 and 5 can be changed.

Reference numeral 7 denotes a four-wheel independent brake mechanism provided on a transmission path of the left front wheel 4L, the right front wheel 4R, the left rear wheel 5L, and the right rear wheel 5R. The brake mechanism 7 is provided on an operation unit. Although the rotation of each wheel is braked based on the operation of a brake pedal (not shown), a multi-plate hydraulic brake mechanism is employed to control a braking rate according to a hydraulic pressure supplied through a path different from the brake pedal. ing.

Reference numerals 8A and 8B denote a pair of inclination sensors provided at the center of the traveling body 1 and the inclination sensors 8A and 8B.
B, one inclination sensor 8A detects the absolute inclination angle of the traveling body 1 in the front-rear direction, while the other inclination sensor 8A
B is attached in a predetermined direction so as to detect the absolute inclination angle of the traveling machine body 1 in the left-right direction.

Reference numerals 9F and 9R denote a pair of acceleration sensors provided at positions corresponding to the support points of the traveling body 1 (above the front wheel axle and above the rear wheel axle).
F and 9R detect the body posture (front-back tilt) based on the detection signals of the acceleration sensors 9F and 9R in order to detect the acceleration when the position corresponding to the front-back support point of the traveling body 1 is accelerated in the vertical direction. Abrupt change in posture).

10F and 10R are a pair of ground height sensors provided at the front end and the rear end of the traveling body 1, respectively. The ground height sensors 10F and 10R are based on detection of reflected ultrasonic waves and the like. In order to measure the ground height at the front end and the rear end of the fuselage, if the detection height of the ground height sensors 10F and 10R becomes higher than the reference height (sensor mounting height), the corresponding side While it can be determined that the wheels 4 and 5 have risen, the ground height sensors 10F and 10F
When the detected height of R is lower than the reference height, it is possible to determine that the corresponding wheel 4, 5 has fallen into the concave portion.

11F and 11R are a pair of rotation sensors provided on the transmission path of the front and rear wheels 4 and 5, respectively. The rotation sensors 11F and 11R control the rotation speed (or rotation speed) of the front and rear wheels 4 and 5, respectively. For detection, it is possible to determine whether the wheels 4 and 5 have lifted or slipped based on the rotation difference between the front and rear wheels 4 and 5.

Reference numeral 12 denotes a microcomputer unit (M
The control unit 12 includes a PU, a ROM, a RAM, and the like. The input unit of the control unit 12 includes the above-described tilt sensors 8A and 8B, the acceleration sensors 9F and 9R, and the ground height sensor 10F. , 10R, rotation sensors 11F, 11R, etc. are connected via an input interface circuit, while on the output side, a clutch electromagnetic valve 13 for controlling the power transmission rate of the main clutch mechanism 3, and a power distribution rate of the center differential 6 Valve 14 for controlling the center differential solenoid valve for controlling the brake ratio, and the electromagnetic valve for brake 1 for controlling the braking rate of each brake mechanism 7
5FL, 15FR, 15RL, 15RR and the like are connected via an output interface circuit. That is, the control unit 12 controls the brake mechanism 7, the center differential 6, the main clutch 3, and the like based on an automatic attitude control routine including subroutines such as front wheel levitation determination, automatic brake control, automatic power distribution control, and automatic clutch control. The control procedure of front wheel levitation determination, automatic brake control, automatic power distribution control, and automatic clutch control will be described below with reference to flowcharts. In this embodiment,
The following describes the control procedure when the front wheel 4 rises, when the fulcrum position of the traveling body 1 is rapidly displaced, and when the traveling body 1 is tilted left or right or back and forth. Even when the wheel 5 slips or the front wheel 4 or the rear wheel 5 falls into the recess, the body posture can be stabilized by automatically controlling the brake mechanism 7, the center differential 6, the main clutch 3 and the like. It is.

In the front wheel floating judgment, a first judgment step of judging the front rising inclination posture of the traveling body 1 based on the inclination detected by the front / rear inclination sensor 8A, and a front ground height sensor 10F
Determination step for determining the lifting of the front end of the aircraft based on the detected height of the front and rear rotation sensors 11F and 11R
And a fourth determining step of determining forward running based on the detection signals of the front and rear rotation sensors 11F and 11R. If YES, the front wheel levitation flag is set, and if any determination is NO, the front wheel levitation flag is reset. That is, since the floating of the front wheel 4 is determined based on a plurality of sensor signals of different detection targets without determining based on a single sensor signal, the front ground height sensor 1
0F detects a depression in the field, or the rotation sensor 11
When F and 11R detect the slip of the front wheels 4, it is possible to prevent the inconvenience of making an erroneous front wheel levitation determination as much as possible.

In the automatic brake control, first, it is determined whether or not the front wheel levitation flag is set.
In the case of S, it is determined based on the detection signal of the front acceleration sensor 9F whether or not the front wheel 4 rises rapidly. If this determination is NO, the left and right rear wheel brake mechanisms 7 are operated at an intermediate braking rate (for example, 50%), while if this determination is YES,
The left and right rear wheel brake mechanisms 7 are operated at the maximum braking rate (100%). That is, when the front wheel 4 is lifted during traveling on an uphill or the like, the rotation of the rear wheel 5 is automatically braked, so that the front wheel 4 can be returned to the ground contact state based on gravity and inertia. 4
When the rising of the front wheel 4 is abrupt, the rear wheel 5 is braked at the maximum braking rate, so that the front wheel 4 that has rapidly risen can be quickly returned to the ground contact state.

On the other hand, if it is determined that the front wheel levitation flag is in the reset state, it is determined whether or not the traveling body 1 is tilted left and right based on the detection signal of the right and left tilt sensor 8B. In some cases, the wheels to be braked based on the inclination direction (the right and left front wheels 4R, 5R in the case of left inclination)
R, the left and right front wheels 4L, 5L in the case of right inclination), and the braking rate is determined based on the inclination angle.
The brake mechanism 7 of the corresponding wheel is operated at this braking rate. That is, when the traveling body 1 is tilted left and right, the wheels on the upper side of the slope are automatically braked at a braking rate according to the inclination, so that the traveling body 1 that is going to turn downward in a straight line is as straight as possible. As a result, it is possible to stabilize the attitude of the body and to reduce the operator's steering operation effort. The braking rate is preset in a stepwise or stepless manner so as to increase in proportion to the inclination angle.

In the automatic power distribution control, first, it is determined whether or not the front wheel levitation flag is set. If the determination is YES, the power transmission rate to the rear wheels 5 is reduced (for example, 0%). ), The power distribution ratio of the center differential mechanism 6 is changed. That is, when the front wheel 4 is lifted up on an uphill run or the like, the rear wheel 5
In order to automatically reduce the driving force of the vehicle, the front wheels 4 can be promptly returned to the ground contact state.

On the other hand, when it is determined that the front wheel levitation flag is in the reset state, it is determined whether or not the traveling body 1 is tilted back and forth based on the detection signal of the front and rear tilt sensor 8A, and the determination is YES. In some cases, the power distribution ratio to the front and rear wheels 4 and 5 is determined based on the inclination direction and the inclination angle, and then the center differential mechanism 6 is operated with the power distribution ratio as a target value. That is, when the traveling body 1 is tilted forward and backward, a large amount of power is automatically distributed to the wheels on the upper side of the slope. Therefore, the traveling body 1 is pulled by the front wheels 4 on the uphill slope, and is pulled by the rear wheels 5 on the downhill slope. The ideal traveling that suppresses the acceleration of the traveling aircraft 1 becomes possible,
As a result, in addition to stabilizing the aircraft attitude,
The climbing performance and the like can be improved. The power distribution ratio is preset stepwise or steplessly so as to increase in proportion to the inclination angle.

In the automatic clutch control, it is determined whether or not the body attitude (front and rear attitude) has changed rapidly based on the detection signals of the acceleration sensors 9F and 9R.
In this case, the power transmission rate of the main clutch mechanism 3 is automatically reduced to a predetermined ratio (for example, 50%). In other words, when the attitude of the aircraft changes suddenly, the driving force of all the wheels is reduced, so that an abrupt change in the attitude of the aircraft can be suppressed. Can be given a margin.

In the vehicle constructed as described above, when the traveling body 1 is tilted left and right, the wheel rotation on the upper side of the slope is automatically braked at a braking rate according to the slope, so that the vehicle tends to turn downward. The traveling body 1 can be maintained in the straight traveling state as much as possible. As a result, it is not allowed to stabilize the body posture and improve the working accuracy, and the operator's operation labor is reduced and operability is reduced. You can measure improvement.

Further, when the front wheel 4 is lifted during traveling on an uphill or the like, the rotation of the rear wheel 5 is automatically braked, so that the front wheel 4 can be returned to the ground contact state based on gravity and inertia.

When the front wheel 4 is rising rapidly, the rear wheel 5 is braked at the maximum braking rate, so that it is possible to suppress the sudden rising of the front wheel 4 or to quickly contact the front wheel 4 with the ground. It can be returned to the state.

In the case where the attitude of the body changes suddenly, the power transmission rate of the main clutch mechanism 3 is automatically reduced. As a result, it is not permissible to quickly stabilize the attitude of the body, and it is possible to provide a margin for the operator's response.

When the traveling body 1 is inclined forward and backward, a large amount of power is automatically distributed to the wheels on the upper side of the slope. Ideal traveling in which the acceleration of the traveling body 1 is suppressed by the wheels 5 becomes possible. As a result, not only is it not possible to stabilize the attitude of the body, but also the climbing performance and the like can be improved.

Further, when the front wheel 4 is lifted up on an uphill run or the like, the driving force of the rear wheel 5 is automatically reduced, so that the front wheel 4 can be returned to the ground contact state.

The determination of the floating of the front wheel 4 is made by the inclination sensor 8A, the ground height sensor 10F, and the rotation sensor 11
Since the detection is performed based on the detection signals of the front wheels 11R and 11R, an erroneous front wheel floating determination is performed when the front ground height sensor 10F detects a concave portion in the field or when the rotation sensors 11F and 11R detect slip of the front wheel 4. As a result, it is possible to prevent the inconvenience of the main clutch mechanism 3, the center differential mechanism 6, the brake mechanism 7 and the like based on an erroneous front wheel floating determination.

The present invention is, of course, not limited to the above-described embodiment. For example, since the brake mechanism of the above-described embodiment is a four-wheel independent type, the inner wheel side is controlled based on the turning operation of the steering wheel. It can be used for turning brake control (small turning control) that automatically brakes the rear wheels, and in this case, it is not possible to use multiple parts, and the steering operation angle It is possible to delicately control the braking rate of the brake mechanism according to the control. The tractor can perform automatic posture control such as automatic brake control, automatic power distribution control, and automatic clutch control with a configuration substantially the same as that of the above-described embodiment, while a combine traveling with a pair of right and left crawler traveling devices 16 can be used. 1
7, a crawler-type traveling body such as the one shown in FIGS. 9 and 10 has an automatic brake control (automatic side clutch control) for automatically braking (intermittently) rotating the crawler on the upper slope in accordance with the lateral inclination of the body. It is possible to perform automatic attitude control such as automatic clutch control for lowering the power transmission rate of the traveling clutch mechanism in response to a sudden change in attitude. However, in FIG. 10, 18 is an engine, 19 is a traveling clutch mechanism, 20L is a left brake mechanism (left side clutch mechanism), and 20R is a right brake mechanism (right side clutch mechanism).

[Brief description of the drawings]

FIG. 1 is a side view of a riding rice transplanter.

FIG. 2 is a block diagram showing an automatic attitude control mechanism for a riding rice transplanter.

FIG. 3 is a flowchart showing front wheel levitation determination.

FIG. 4 is a flowchart showing automatic brake control.

FIG. 5 is a flowchart showing automatic power distribution control.

FIG. 6 is a flowchart showing automatic clutch control.

FIG. 7 is a diagram illustrating the operation of automatic brake control.

FIG. 8 is a diagram illustrating the operation of automatic power distribution control.

FIG. 9 is a side view of a combine showing another example.

FIG. 10 is a block diagram showing an automatic attitude control mechanism for combine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Running body 2 Engine 3 Main clutch mechanism 4 Front wheel 5 Rear wheel 6 Center differential mechanism 7 Brake mechanism 8 Tilt sensor 9 Acceleration sensor 10 Ground height sensor 11 Rotation sensor 12 Control unit

Claims (3)

[Claims] 1. A work vehicle having a brake mechanism for braking the rotation of a wheel provided on a travel body traveling with rotation of the wheel, wherein the work vehicle has an inclination of the vehicle. , A body attitude determining means for determining the body attitude based on the detection signal of the tilt sensor, and a body attitude by automatically braking the rotation of a predetermined wheel when the traveling body is tilted. Work vehicle provided with automatic brake control means for stabilizing the vehicle. 2. A work vehicle comprising a traveling body traveling with the rotation of a wheel body and a brake mechanism for braking the rotation of the wheel body, wherein the work vehicle has an abrupt movement of the traveling body. An acceleration sensor that detects a sudden change in attitude, a body attitude determination unit that determines a sudden change in the attitude of the traveling body based on a detection signal of the acceleration sensor, and a predetermined wheel body when the body attitude changes abruptly. A work vehicle equipped with automatic brake control means for automatically braking the rotation to stabilize the attitude of the aircraft. 3. A power distribution mechanism for changing distribution of power transmitted to front and rear wheels according to claim 1 or 2, and automatic distribution of power transmitted to front and rear wheels when a body posture changes. A working vehicle provided with automatic power distribution control means for stabilizing the attitude of the aircraft by changing the position.