JP3310597B2 - Agricultural tractor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilling apparatus which is connected to a traveling vehicle body in a rolling manner by driving an actuator, and drives the actuator based on a signal from a rolling sensor for measuring a rolling angle of the traveling vehicle body. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agricultural tractor provided with a control device capable of performing rolling control for maintaining a rolling posture of a tilling device, and more particularly, to an improvement in technology for changing a form of rolling control.

[0002]

2. Description of the Related Art Conventionally, there is an agricultural tractor constructed as described above in Japanese Patent Publication No. Hei 6-71363. In this conventional example, a dead zone width of a rolling control is changed based on a vehicle speed, and a rolling cylinder is used. It is configured to change the form of the rolling control by adjusting the operating speed of.

[0003]

In a plowing operation with a tractor equipped with a tilling device, when a control for maintaining the tilling device in a predetermined rolling posture is performed, a rolling sensor for measuring a rolling angle of a traveling vehicle body is used. Is controlled based on the signal of (1) to drive the actuator so that the tillage device maintains a predetermined ground rolling posture. In addition, the control for rolling the tilling device by driving the actuator in this manner is caused by a phenomenon such that one wheel falls into a concave part such as a rut in a field or one wheel runs on a convex part such as a lump of soil in a field. I do.

Further, when rolling the tilling device when the posture of the vehicle body changes, the rolling operation of the tilling device quickly in conjunction with the speed of the fluctuation of the vehicle body posture can maintain the posture of the tilling device with respect to the field. However, in reality, rolling a heavy tiller at high speed requires not only a large-capacity actuator, but also when a heavy tiller is operated at high speed. It is also difficult to suppress the overshoot of the cultivator, and it is difficult to control the tilling apparatus to maintain an appropriate posture.
Particularly, when the rolling control is performed at the same time as the plowing operation by running the body at high speed in a rough field, the body frequently shakes in a short period of time, and the body shakes as if bouncing. The amplitude is also large. In such a situation, when the tillage device is rolled at a high speed for the purpose of maintaining the predetermined rolling posture, not only the above-described overshoot but also a control for maintaining an appropriate rolling posture due to the influence of the control delay. It is difficult to perform, for example, when the right side of the tillage device is to be driven in the upward direction, a phenomenon in which the right side is lowered is performed. There is room.

An object of the present invention is to provide an agricultural tractor capable of suppressing useless operation of rolling control and flattening a plowed field scene even when a vehicle is driven at high speed in a rough field to perform work. The point is to construct it rationally.

[0006]

A first feature of the present invention (claim 1) is that a lift cylinder is driven with respect to a traveling vehicle body.
It can be moved up and down freely and the rolling cylinder is driven by rolling cylinder.
To measure the rolling angle of the running vehicle
And the ground surface after tilling with a tilling device
A ground sensor that measures the ground height based on the reference
Adjust the lift system so that the sensor
Automatic tillage control to drive the cylinder and the rolling sensor
Driving the rolling cylinder based on the measured value
And an automatic rolling control to maintain a low ring attitude of location
Agricultural tractors equipped with the following
It is in. Equipped with a speed sensor to measure the traveling speed of the traveling vehicle
The traveling speed of the traveling body is 3 to 4 km / h,
Rolling frequency measured by rolling sensor increases
The lowering of the automatic tillage control,
Rolling speed of rolling control becomes low and rolling
Together configured to stroke decreases, Lori
Supply and discharge of hydraulic oil per unit time at the control valve of the operating cylinder
By reducing the volume, automatic rolling control
The ring speed is configured to be low.

A second aspect of the present invention (claim 2), running
The lift cylinder is driven up and down and low
The tillage device can be connected freely by rolling the ring cylinder.
To measure the rolling angle of the running vehicle.
And ground height based on the ground surface after tilling with a tilling device
And a ground sensor for measuring the
Drive the lift cylinder to maintain the target plowing depth
Based on automatic tillage depth control and rolling sensor measurement
The rolling appearance of the tilling device driven by the rolling cylinder
Agricultural tractor with automatic rolling control to maintain momentum
In the following configuration. Traveling body
Comprising a speed sensor for measuring the running speed, run the vehicle body
Line speed is 3 to 4 km / h, with rolling sensor
As the measured rolling frequency increases, the automatic tillage control
Control of lifting and lowering, and automatic rolling control
Low rolling speed and small rolling stroke
And automatic rolling control.
To expand the dead zone set based on your goals
The rolling stroke of automatic rolling control is smaller
It is configured to be easy.

According to the first and second features, when the traveling speed of the traveling vehicle body is increased, the rolling frequency measured by the rolling sensor increases, or the rolling measured by the rolling sensor increases. As the angle increases, the control mode changing means changes the control mode in a direction to suppress the rolling operation of the tilling device, and the rolling operation of the tilling device is suppressed even when the cultivating device reaches a rolling angle that requires rolling. It will be. In other words, when the traveling speed of the traveling vehicle increases, the rolling angle and the rolling frequency of the vehicle increase, which means that the number of irregularities in the field scene per unit traveling distance is large, or the height difference of the irregularities is large. In such a case, it is difficult to roll the tilling device following the rolling of the vehicle body that occurs frequently, so by slowing down the rolling operation without actively performing the control to follow the rolling, This prevents the tilling device from rolling in an inappropriate direction due to overshoot or control delay, thereby flattening the field scene after tilling.

According to the first feature , when the control mode is changed so as to suppress the rolling operation of the tillage device, the supply and discharge amount of the hydraulic oil per unit time at the control valve is reduced, so that the operating speed is reduced. Is reduced to prevent an excessive rolling operation.

According to the second feature , when the control mode is changed in a direction to suppress the rolling operation of the tilling device, the dead zone is expanded, and the measurement result from the rolling sensor deviates from the control target. Also in this case, the control is started when the deviation amount becomes larger, and the control ends in a state where the deviation amount is large. That is, since the control start tends to be delayed and the control end tends to end earlier, the sensitive rolling operation is prevented.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, an engine 4 is disposed at a front portion of a vehicle body 3 having a front wheel 1 and a rear wheel 2, and a transmission case 5 to which power from the engine 4 is transmitted is provided at a rear portion of the vehicle body 3. The driver's seat 7 is disposed at an intermediate position between the left and right rear fenders 6 above the transmission case 5, the steering handle 8 is disposed at the front of the driver's seat 7, and the driver's seat 7 is located at the rear end of the vehicle body 3. The rotary tilling device 10 is connected to the rotary tilling device 10 so as to be able to move up and down and rolling freely via the two-point link mechanism 9, and is operated by a single-acting lift cylinder 11 disposed at an upper position of the transmission case 5. The pair of lift arms 12 and the two-point link mechanism 9 are connected to each other via the left and right lift rods 13 so as to be supported in a suspended state. By Linda 14 <br/> interposed, a drive lift of the rotary plow 10,
The agricultural tractor can be freely driven and rolled around the rolling axis X in the front-rear direction.

[0012] As shown in FIG.
The hydraulic system for driving up and down and driving rolling includes a hydraulic pump P driven by the engine 4, a flow priority valve 17 for flow control, and a control flow from the flow priority valve 17 for rolling. It comprises a rolling solenoid valve 18 for supplying to the cylinder 14 and an electromagnetic proportional control valve V for supplying surplus flow from the flow priority valve 17 to the lift cylinder 11 or discharging oil from the lift cylinder 11. The electromagnetic proportional control valve V includes a first valve 19 for ascending control,
Second valve 20 for pilot pressure control for opening and closing valve 19
And a third valve 21 for lowering control, a fourth valve 22 for pilot pressure control for opening and closing the third valve 21, and a relief valve 23. A current is supplied to the electromagnetic solenoid 20A of the second valve 20, and the first valve 19 is controlled by adjusting the supplied current.
As a result of the change of the pilot pressure acting on the valve, the opening of the valve is obtained in proportion to the current value, and the ascending speed is obtained in proportion to the opening. Has an electromagnetic solenoid 22A of the fourth valve 22
While supplying current to the
As a result of the change of the pilot pressure acting on the second valve 20, the opening degree of the valve is obtained in proportion to this current value, and a descending speed proportional to the opening degree is obtained.

In this agricultural tractor, the rotary tilling device 1
Automatic tillage depth control for maintaining 0 at a predetermined height based on a field scene (ground), position control for raising and lowering the rotary tillage device 10 to a predetermined height based on the vehicle body 3, and a rolling shaft in a front-back posture. Rotary tilling device 10 around core X
And the rolling tillage device 10 is maintained at a predetermined rolling posture, and the rotary tillage device 10 is raised to a predetermined height with respect to the vehicle body in preference to the three types of control. And a control system for performing forced ascent control for setting and maintaining the rolling posture.

Further, the driver's seat 7 is controlled so as to perform automatic plowing depth control.
The control box 24 is provided on the upper surface of the rear fender 6 on the right side of the vehicle, and the control box 24 is provided with a potentiometer-type tillage depth setting device 25. Rear cover 10 configured to be swingable about axis Y
A potentiometer-type grounding sensor 26 that measures the ground height of the rotary tillage device 10 based on the field scene (ground surface) after plowing from the swing amount of A is provided. At the base end of a lift lever 27 disposed on the right side of the driver's seat 7 is provided a potentiometer type position setting device 28, and at the base end of the lift arm 12, a rotary tilling device 10 is provided based on the swing amount of the lift arm 12.
The control box 24 is provided with a potentiometer-type rolling angle setting device 30 so as to perform rolling control. A rolling sensor 31 for electrically measuring the amount of rolling of the vehicle body 3 in the left-right direction, a stroke sensor 32 for measuring the amount of expansion and contraction of the rolling cylinder 14 at a position near the rolling cylinder 14, and As shown in FIG. 4, the post portion 33 of the steering handle 8 is vertically operable so as to perform forced ascent control, and is urged to return to the neutral position N, as well as the ascending position U and the descending position. Forced lifting lever 3 operable with D
4 is provided, and a forced lifting switch 35 for detecting the operation direction of the lever 34 is provided at the base end of the lever 34. Further, in this agricultural tractor, as shown in FIG. 5, a pickup type that measures the running speed of the vehicle body from the rotation speed of the input shaft 38 of the differential device 37 with respect to the rear wheel 2 from the gear type transmission 36 incorporated in the transmission case 5. The speed sensor 39 is used for setting the control sensitivity of the automatic plowing depth control and the automatic rolling control as described later.

As shown in FIG. 6, the tillage depth setting device 25,
Grounding sensor 26, position setting device 28, lift arm sensor 29, rolling angle setting device 30, rolling sensor 31, stroke sensor 32, forced lifting switch 3
5. The control device 40 includes a system for inputting a signal from each of the speed sensors 39, and a system for outputting control signals to the electromagnetic proportional control valve V and the rolling electromagnetic valve 18.

The outline of the automatic cultivation depth control is as follows.
The lift cylinder 11 is driven to move the rotary tillage device 10 up and down so that the measurement value from the ground contact sensor 26 changes toward the value of the target plowing depth set in the above, and the dead zone set based on the target plowing depth is set. When the measured value from the ground sensor 26 reaches the signal area, the operation is set so as to stop the raising and lowering of the rotary tilling device 10, and the outline of the position control is the same as the target height set by the position setting unit 28. The rotary tilling device 10 is moved up and down by driving the lift cylinder 11 so that the signal from the lift arm sensor 29 changes toward the value, and the signal from the lift arm sensor 29 is moved to the signal range of the dead zone set based on the target height. The operation of stopping the elevation of the rotary tillage device 10 when a signal is reached is set. The outline of the automatic rolling control is the rolling angle. A ground rolling angle of the rotary tiller 10 set in Joki 30, rolling sensor 31
The target length of the rolling cylinder 14 is obtained based on the rolling angle of the vehicle body 3 in the left-right direction measured by the above-described method, and the value of the rolling cylinder 14 is changed toward the value of the target length. 14 and an operation of stopping the rolling control when a signal from the stroke sensor 32 reaches a signal zone of a dead zone set based on the target length. By operating the lever 34 to the ascending position U, the rotary tiller 10 is raised until a signal from the lift arm sensor 29 reaches a signal range of a dead zone set based on a preset upper limit as a reference, and automatic rolling control is performed. When the rotary tilling device 10 is in a state of being inclined with respect to the vehicle body 3, it reaches a posture without inclination with respect to the vehicle body 3. Is intended to drive the rolling cylinder 14 to the lowering position D the forcible lift lever 34
To perform the control to lower the rotary tillage device 10 to the height before the forced ascent control is performed (to the height at which the automatic tillage control is performed when the forced ascent is performed in the automatic plowing control state). Has become.

Further, this agricultural tractor is configured to be capable of automatic plowing depth control in a relatively high-speed running state of 3 to 4 km / h (conventionally, the limit is about 1.8 km / h). When the vehicle body 3 is driven at a high speed in a field scene in which many irregularities due to ruts are formed like a headland and an automatic rolling control is performed simultaneously with an automatic plowing depth control, a plowing operation is performed. When the vehicle body 3 rolls a lot in a short time based on the above, or when the vehicle body 3 rolls a lot, the raising and lowering operation and the rolling operation in the automatic plowing depth control and the automatic rolling control are suppressed, so that the field after plowing is controlled. The surface is configured to be flat, and the control operation thereof will be described below.

When performing the automatic plowing depth control and the automatic rolling control, a parameter setting routine is executed prior to these controls to obtain data necessary for the control. That is, as shown in the flowchart of FIG. 7, first, a signal from the speed sensor 39 is input to determine whether the traveling speed of the vehicle body 3 is equal to or higher than the set value (Steps # 101 and # 102). In some cases, the rolling sensor 3
The signal from 1 is input and the number of times of rolling (frequency) per unit time and the rolling angle are measured, and it is determined whether any of them is greater than a set value. , The valve drive parameters and the dead zone parameters are set based on the table data, and the sampling parameters used for the automatic rolling control are set based on the table data (steps # 103 to # 107). Further, when the traveling speed of the vehicle body 3 measured by the speed sensor 39 is equal to or less than the set value, and when the rolling frequency (frequency) measured by the rolling sensor 31 per unit time and the rolling angle are both set values. If it is below, each of the valve drive parameter and the dead zone parameter is set to the initial value (# 108 step).

In step # 106, the table data for setting each of the valve drive parameter and the dead zone parameter includes a large measured value (vehicle speed) by the speed sensor 39, a measured value of the number of times of rolling (frequency), and a measured value of the rolling angle. The characteristic is set so as to reduce the flow rate of the hydraulic oil supplied / discharged by the electromagnetic proportional control valve V and at the same time expand the dead zone (width) (see the graph in the same step), and the number of rolling ( Frequency) or, if the rolling angle is greater than or equal to the set value, this rolling frequency,
Alternatively, the valve drive parameter and the dead zone parameter are read from the table data based on the rolling angle and the traveling speed of the vehicle body 3, and if both the number of times of rolling (frequency) and the rolling angle are equal to or larger than the set values, the rolling is performed. The valve drive parameters and the dead zone parameters are read from the table data based on the number of times (frequency), the rolling angle, and the running speed of the vehicle body.

Further, as the valve driving parameter increases, the power supplied to the electromagnetic proportional control valve V decreases as the number of times of rolling (frequency) increases, as the rolling angle increases, or as the traveling speed increases. It is a numerical value for determining the duty ratio for reducing the opening degree of the valve V, and the dead zone parameter increases as the number of times of rolling (frequency) increases or as the rolling angle increases.
Alternatively, it is a numerical value for expanding the area (width) of the dead zone set based on the target plowing depth as the traveling speed increases.

In step # 107, the table data for setting the sampling parameters is such that the larger the measured value of the speed sensor (vehicle speed), the measured value of the number of times of rolling (frequency), and the measured value of the rolling angle, the larger the value within a unit time. The characteristic is set so as to increase the number of times of sampling. If the number of times of rolling (frequency) or the rolling angle is equal to or larger than a set value, the rolling frequency or the rolling angle and the traveling speed of the vehicle body 3 The sampling parameter is read from the table data based on the number of times (frequency) and the rolling angle are both equal to or greater than a set value, and based on the number of times of rolling (frequency), the rolling angle, and the traveling speed of the vehicle body. The sampling parameters are read from the table data.

In step # 108, the initial values set for each of the valve drive parameter and the dead zone parameter are preset numerical values. When the vehicle speed is low, or even when the vehicle speed is high, the number of times of rolling (frequency If the measured value of (1) and the measured value of the rolling angle are smaller than predetermined values, appropriate automatic lifting control and automatic rolling control are enabled.

As shown in the flowchart of FIG. 8, in the automatic tillage depth control, a signal from the tillage depth setting device 25 is input to set a target tillage depth, and based on the dead zone parameter based on the target tillage depth. Set the dead zone of the area (# 20
1, # 202 step) Further, a signal from the ground contact sensor 26 is input, and it is determined whether or not this signal value is set as described above and is within the dead zone of the target plowing depth. If the control is not performed and the power is outside the dead zone, the intermittent power of the duty ratio based on the valve drive parameter is changed to the electromagnetic proportional control valve V
, The tillage device is raised and lowered (steps # 203 to # 205).

As shown in the flowchart of FIG. 9, in the automatic rolling control, a signal from a rolling angle setter is input, a measurement signal is input from a rolling sensor at a cycle based on the sampling parameter, and the measurement signal is averaged. Then, the target length of the rolling cylinder is calculated and obtained from the deviation between the processing result and the signal from the rolling setter (# 301 to # 304 steps).
In the averaging process, a sum of sampled data is obtained, and an average value is obtained by dividing (dividing) the value of the sum by the number of times of sampling.

Next, a dead zone of a range based on the parameter is set based on the target length, a signal from the stroke sensor 32 is input, and it is determined whether or not this signal value is within the dead zone of the target length. If it is within the dead zone, the rolling control is not performed, and if it is outside the dead zone, the intermittent power based on the valve drive parameter is supplied to the rolling solenoid valve 18 to perform rolling of the tilling device (#). 305 to # 208 steps). # 303, # 3
Steps # 05 and # 308 are an example of the control mode changing means E in claim 1. In step # 303 , the rolling operation is suppressed by increasing the sampling number, and in step # 305 , the rolling operation is performed by expanding the dead zone. Restrain
(Claim 2) In step # 308, the rolling operation is suppressed (Claim 1) by reducing the amount of hydraulic oil supplied and discharged via the control valve.

As described above, according to the present invention, when the traveling speed of the vehicle body 3 is equal to or higher than the predetermined value, the degree of roughness (the degree of unevenness) of the field scene is determined based on the signal from the rolling sensor 31, and the roughness is severe. In this case, the start of the rolling operation of the rotary tilling device 10 is delayed as the degree of roughness is severe, and the rolling stroke of the rotary tilling device 10 is reduced by speeding up the end of the rolling operation, and the speed at the time of the rolling operation is reduced. As a result, the excessive rolling operation following the field scene is prevented by lowering the speed. As a result, the occurrence of overshoot is suppressed, and at the same time when the right side of the rotary tillage device needs to be raised, the rotary tillage device 10 The operation in the reverse direction, such as descending, is prevented, and the field scene after plowing can be flattened.

[Other Embodiments] In the above embodiment, the data for setting the valve opening and the data for setting the dead zone are obtained from preset table data, but in the present invention, the traveling speed, the number of rolling times ( Frequency) and the rolling angle. Further, it is also possible to implement the control mode changing means for suppressing the rolling operation by using only one of the processes for limiting the supply and discharge amount of the hydraulic oil or expanding the dead zone.

[0028]

Therefore, even when the vehicle is driven at high speed in a rough field and the work is performed, the agricultural tractor which suppresses useless operation of the rolling control and flattens the field scene after plowing is reasonable. (Claim 1). Further, the rolling operation can be suppressed by reducing the speed by a simple means of changing the supply / discharge amount of the hydraulic oil via the control valve (claim 1), and the extremely simple means of changing the electric processing. The rolling operation could be suppressed by changing the timing of starting and stopping the rolling operation (claim 2).

[Brief description of the drawings]

FIG. 1 is an overall side view of an agricultural tractor.

FIG. 2 is a rear view of the agricultural tractor.

FIG. 3 is a hydraulic circuit diagram of a lifting system and a rolling system.

FIG. 4 is a side view showing an arrangement of a forced lifting lever.

FIG. 5 is a schematic diagram of a transmission system showing an arrangement of a speed sensor.

FIG. 6 is a block circuit diagram of a control system.

FIG. 7 is a flowchart of a parameter setting routine.

FIG. 8 is a flowchart of automatic plowing depth control.

FIG. 9 is a flowchart of automatic rolling control.

[Explanation of symbols]

Reference Signs List 3 Running body 10 Tilling device 11 Lift cylinder 14 Rolling cylinder 18 Control valve 26 Ground contact sensor 31 Rolling sensor 39 Speed sensor 40 Control device

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-103502 (JP, A) JP-A-3-198701 (JP, A) JP-A-3-193517 (JP, A) JP-A-63-1988 129904 (JP, A) Japanese Utility Model 531505 (JP, U) Japanese Utility Model 57-97734 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) A01B 63/10 A01B 63 / 114

Claims (2)

(57) [Claims] 1. Driving of a lift cylinder with respect to a traveling vehicle body
Connecting the rolling freely plow in the driving of the vertically movable and rolling cylinder, a rolling sensor for measuring the rolling angle of the vehicle body, relative to the ground surface after tilling of the plow-ground
With a contact sensor for measuring the height, so as to maintain the measured value of the contact sensor at the target plowing depth,
Automatic plowing depth control for driving the lift cylinder, and the rolling control based on the measurement value of the rolling sensor.
An agricultural rolling tractor having an automatic rolling control for driving a rolling cylinder and maintaining a rolling posture of the tilling device , comprising a speed sensor for measuring a running speed of the running vehicle , wherein the running speed of the running vehicle is 3 hours / hour. ~ 4 kilometers before
Rolling frequency measured by the rolling sensor increases
The more the vertical movement of the automatic plowing depth control is suppressed,
The rolling speed of the automatic rolling control becomes low and
When the rolling stroke is configured to be small
Both are units of hydraulic oil in the control valve of the rolling cylinder.
By reducing the time supply and discharge, the automatic loading
The rolling speed of the rolling control is configured to be low.
A farm tractor. 2. Driving of a lift cylinder with respect to a traveling vehicle body
Up and down freely and rolling by driving a rolling cylinder
A rolling center that freely connects tillage devices and measures the rolling angle of the running vehicle
And the ground based on the ground surface of the tillage device after the tillage
With a contact sensor for measuring the height, so as to maintain the measured value of the contact sensor at the target plowing depth,
Automatic plowing depth control for driving the lift cylinder, and the rolling control based on the measurement value of the rolling sensor.
Drive cylinder and change the rolling posture of the tillage device.
With agricultural tractor with automatic rolling control to maintain
A traveling speed sensor for measuring a traveling speed of the traveling vehicle , wherein the traveling speed of the traveling vehicle is 3 to 4 km / h;
Rolling frequency measured by the rolling sensor increases
The more the vertical movement of the automatic plowing depth control is suppressed,
The rolling speed of the automatic rolling control becomes low and
When the rolling stroke is configured to be small
Both were set based on the control target of the automatic rolling control.
By expanding the dead zone, the automatic rolling
Control rolling stroke is configured to be small.
Agricultural tractors are.