JP2959155B2 - Rolling control device for ground work machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling control device for a ground working machine such as a rotary tilling device connected to a rear portion of a tractor.

[0002]

2. Description of the Related Art Conventionally, a lower part of a tractor is provided with a three-point link mechanism comprising a top link and a lower link.
Tari tilling equipment is connected so that it can move up and down freely.
The lift arm on the side and the lower link are connected by a lift rod. Then, at least one of the left and right lift rods is constituted by a hydraulic cylinder that can be extended and contracted, and by operating this, the inclination posture of the rotary tilling device is changed.

[0003]

In such a conventional apparatus, a plurality of detected values detected by the tilt detector are weighted and averaged, and the result is used as the attitude control means, that is, the target stroke value of the hydraulic cylinder. And the attitude changing means is controlled based on the difference between the target stroke value and the value of the stroke detector at this time, so that control delay may be involved. .

More specifically, in the conventional apparatus, when the body tilts in the left-right direction, the change is detected by a tilt detector, the detected values are weighted and averaged, and then the control of the hydraulic cylinder is performed. A target stroke value as a target value is determined, and a difference between the target stroke value and a value of a stroke detector before the aircraft starts tilting is calculated, and based on this, the deviation is reduced to zero. Since the expansion and contraction of the hydraulic cylinder is controlled so as to approach, it takes time from the detection of the lateral inclination of the body to the start of the control, resulting in a delay in control.

[0005]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above problems, and has taken the following technical measures. That is, an inclination detector 16 for detecting the inclination of the body 1 in the horizontal direction, a posture changing means 15a for changing the inclination posture of the ground work machine 14 connected to the body 1, and the body 1 and the ground work machine 14. A stroke detector 17 for detecting a relative angle difference, wherein the attitude changing means 15a is operated when the body 1 is tilted in the horizontal direction to maintain the ground work machine 14 at a predetermined angle. In the rolling control device for the ground work machine, the target stroke of the attitude changing means 15a is calculated based on the value detected by the tilt detector 16 and the set value set by the tilt setter 18. The difference between the value and the stroke value of the attitude changing means 15a immediately before the body 1 starts tilting is averaged, and the average value is used as a control target value to control the attitude changing means 15a to expand and contract. It is.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. First, a description will be given of the configuration. Reference numeral 1 denotes a tractor provided with front wheels 2 and 2 and rear wheels 3 and 3 at front and rear portions of the fuselage, respectively.
At the rear upper part of the transmission case 4 is a hydraulic cylinder case 5
Is fixedly provided. A single-acting hydraulic cylinder 6 is provided in the hydraulic cylinder case 5, and lift arms 7, 7 are rotatably supported on both left and right sides of the hydraulic cylinder case 5. Here, the hydraulic cylinder 6, and the lift arms 7, 7 are collectively referred to as a hydraulic lift mechanism 8. However, by appropriately switching a control valve described later, hydraulic oil is supplied and discharged into the hydraulic cylinder 6, and the lift The arms 7, 7 rotate up and down.

[0007] Top link 10, lower link 11, 1
1, a rotary tillage device 14 as a ground working machine is connected to the rear end of the three-point link mechanism 12 such that it can move up and down freely, and between the lift arms 7, 7 and the lower links 11, 11. Is connected to the lift rods 15 and 15 interposed therebetween.
Of these, the right lift rod 15 is composed of a double-acting hydraulic cylinder 15a. Hydraulic oil is supplied to and discharged from the hydraulic cylinder 15a by switching of a control valve, which will be described later. Let it.

Reference numeral 16 denotes an inclination detector attached to the lateral side of the hydraulic cylinder case 5, which detects the inclination of the tractor 1 in the left and right directions. 17 is a tractor
1 is a stroke detector for detecting a relative angle difference between the rotary cylinder 1 and the rotary tillage device 14, and is constituted by a linear potentiometer. The stroke detector 17 is provided with the hydraulic cylinder 15a. It is arranged on the lateral side.

Reference numeral 20 denotes a hydraulic control lever for position control, and a turning base of the hydraulic control lever 20 includes:
A ground height setting device 21 for setting the ground height of the rotary tillage device 14 connected to the rear of the tractor-1 is attached. On the other hand, a ground height detector 23 for detecting the rotation angle of the lift arm 7, that is, the height of the ground work machine, is also attached to the rotation base of the one-side lift arm 7.
The lift arms 7, 7 rotate to the position set at 0 and stop at the set position.

The structure of a rotary tilling device as a ground working machine will be briefly described. The rotary tilling device 14 includes a tilling portion 34, a main cover 35 covering the upper portion of the tilling portion 34, and a A rear cover 36 pivotally attached to a rear portion of the cover 35, and a lower end of the rear cover 36 is slidably contacted with the ground so as to be elastically pressed so as to level the plowed soil surface; A rear cover is provided at the upper rear end of the main cover 35.
A tillage depth detector 37 for detecting the rotation angle of the 36 is provided.

Next, a control system of the control device will be described with reference to a block diagram shown in FIG. The tillage setting device 40 for setting the height of the ground working machine and the tilt setting device 18 for setting the left-right tilt angle of the ground working machine are connected to a control device 27 composed of a CPU via an A / D converter 25, respectively. Similarly, the ground height detector 23, the tillage depth detector 37, the tilt detector 16 for detecting the tilt angle of the tractor-1, and the stroke detector 17 are also connected via the A / D converter 25. Connected to the control device 27. Then, on the output side of the control device 27,
Lift proportional control valve 4 for moving lift arms 7, 7 up and down
6, a descending proportional control valve 47, and an extending control valve 48 and a shortening control valve 49 for extending and retracting the hydraulic cylinder 15a for changing the inclination posture of the ground work machine are connected.

Reference numeral 28 denotes a lifting switch directly connected to the control device 27 without passing through the A / D converter 25. When this switch 28 is turned on, the ground work machine rises to the maximum rising position, and when it is turned off, it is turned off. It descends to the height set by the hydraulic operation lever 20. FIG. 3 shows the contents of the rolling control program stored in the storage device of the control device 27, which will be described below.

First, each detected value, that is, the value detected by the tillage depth detector 37, the tilt detector 16, and the stroke detector 17, and each set value, that is, the tillage depth setter 40, the tilt setting The set value by the heater 18 is read into the CPU (step S1), and when the control mode is horizontal control (step S1).
In 2), the target stroke value (STMn) of the hydraulic cylinder 15a is calculated by comparing the current value of the tilt detector 16 with the value set by the tilt setting device 18 (step S).
3).

Usually, in such a case, the rotary tilling device 14 is often used while being kept horizontal, so that the setting of the inclination setting device 18 is instructed to be "horizontal". In the conventional apparatus, the detected value of the inclination detector 16 is weighted and averaged to obtain basic data for control. However, in the present invention, such averaging processing is not performed. Then, when the aircraft tilts in either direction, the tilt detector 16 detects the motion,
The target stroke value (STMn) is calculated. At the same time, when the rotary tilling apparatus 14 starts to tilt, the stroke value (STn) immediately before that is detected by the stroke detector 17. STn is a value at the time when the rotary tillage device 14 starts to incline.
This indicates the true inclination angle of the tall cultivator 14.

In order to improve the accuracy of the rolling control,
The hydraulic cylinder 15a may be expanded and contracted so that the difference (In) between the (STMn) and the (STn) disappears.
In step S4, a difference (ln) between the two is obtained, a weighted average is taken, and an average value (Ln) of the difference is calculated (step S5). When the difference (Ln) is within the dead zone (step S6), the output to the ascending proportional control valve 46 or the descending proportional control valve 47 is stopped (step S1).
6) Then, it is out of the dead zone and (STM
Only when the difference (ln) between (n) and (STn) is out of the neutral state, the hydraulic cylinder 15a is extended or shortened.

In this case, when it is determined that the body 1 is tilted to the right and the rotary tillage device 14 is in the downward right position, the hydraulic cylinder 15a is shortened, and conversely, it is determined that the rotary tilling device 14 is in the upward right position. In this case, the extension control valve 48 is excited to extend the hydraulic cylinder 15a. In this case, the speed at which the hydraulic cylinder 15a expands and contracts is such that a continuous signal is sent to the control valves 48 and 49 when the deviation is large,
When the deviation is within a minute range, a pulse signal is given, and this point is not different from the conventional apparatus.

A feature of this control program is that if (ln) is in a neutral state in steps S7 and S15, control is stopped even if (Ln) is out of the dead zone. That is, even if the average value (Ln) of the difference is out of the dead zone, the latest unprocessed control data (In) before taking the average is neutral, in other words, the difference between (STMn) and (STn). If the difference is close to zero or substantially zero, the control target value is reset to the "horizontal state" by substituting zero into the value of (Ln, Ln-1,... Ln-4) as shown in step S15. Then, the rolling control is stopped.

As described above, when the target inclination angle of the working machine is “horizontal”, the conventional apparatus is sensitive to even a slight vibration, particularly when working in a hard field. Hunting. In order to solve the problem, there is a delay timer that controls the opposite output for a certain period of time, but if a delay timer that controls the output on the opposite side is inserted, There is a disadvantage that the working machine may be kept slightly tilted by being deviated by about 1 to 2 degrees to one side in the left-right direction, and the horizontal posture cannot be accurately maintained.
However, as described above, the difference between the current value of the stroke detector 17 for detecting the length of the hydraulic cylinder 15a and the target stroke value is within a predetermined width (a width recognized as neutral).
In this case, the past average data is regarded as zero and all the data are returned to the reset state. Therefore, the stability near the horizontal level increases, and the movement near the horizontal level, which has conventionally occurred, is excessive. No bias appears.

Next, the operation of the flowchart of FIG. 4 will be described. The purpose of this control program is to increase the stability near the horizontal when the working machine is maintained in a horizontal posture. As described above, in the case of the day-timer type in which the reverse output is prohibited for a certain period of time, when the work machine itself is near the horizontal, the work machine may stop at a position shifted to the left or right from the horizontal position. However, the feature of this improved program is that the pulse output is started from OFF.

The description of the flowchart of FIG. 4 that is the same as that of FIG. 3 will be omitted, and the operation of step S6 and subsequent steps will be briefly described. For example, when (Ln) exceeds the dead zone and the hydraulic cylinder 15a must be extended, whether the difference between the target value and the set value, that is, the deviation is small, in other words, whether the difference is in the pulse control range or not. It is determined whether or not this is the case (steps S6 and S7). If not, a continuous output on the "extension" side is output to excite the extension control valve 48.

Immediately after the deviation is small and the pulse output is requested, an OFF timer is set and an OFF signal is issued for a fixed time (about 300 msec) (step S).
8, S9, S10, S24). Fixed time (300mse
c) After counting whether or not it has elapsed, set the ON timer this time and turn ON for a fixed time (300 msec)
Output signals (steps 11, S12, S13, S2
4).

In this embodiment, the OFF-side and ON-side pulse energizing times are the same, but one energizing time may be changed. Further, the control valves for extension and contraction may be proportional control valves, and so-called duty control for changing the ON time based on the deviation may be performed. Steps S16 to S21
The operation on the shortening side is the same as that on the extension side, and only the operation direction is different.

As described above, in the tilt attitude control apparatus for driving the hydraulic cylinder 15a to expand and contract, in the pulse control area, when an output request is made as in the prior art, the pulse output is started from ON. Instead of the above, it is configured to start from OFF, which eliminates the need for the reverse output delay timer that was required in the past. In addition, when the inclination of the body is large and the deviation is large, the output request is the same as before. As soon as there is a continuous signal is output, the control valve 4
8 (or 49) is driven by excitation, and it is possible to provide a control device having excellent responsiveness without control delay.

[0024]

As described above, the present invention provides:
Tilt detector 16 for detecting the lateral inclination of the body 1
A posture changing means 15a for changing the inclination posture of the ground work machine 14 connected to the body 1, the body 1 and the ground work machine 14
And a stroke detector 17 for detecting a relative angle difference between the ground work machine 14 and the ground work machine 14 at a predetermined angle by operating the attitude changing means 15a when the body 1 is tilted in the horizontal direction. In the rolling control device for a ground working machine having the above configuration, the target stroke of the attitude changing means 15a is calculated based on the value detected by the tilt detector 16 and the set value set by the tilt setter 18. Since the difference between the stroke value and the stroke value of the attitude changing means 15a immediately before the body 1 starts tilting is averaged, the average value is used as a control target value to control the attitude changing means 15a to expand and contract. In addition, the control delay caused by averaging the detection values of the tilt detector and performing the horizontal control as in the conventional device is small, and the response of the control is improved.

[Brief description of the drawings]

FIG. 1 is a side view of a tractor and a rotary tillage device.

FIG. 2 is a block diagram showing a control system.

FIG. 3 is a flowchart of horizontal control.

FIG. 4 is a flowchart in which a part of the program shown in FIG. 3 is improved.
It is a chart.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tractor 2 Front wheel 3 Rear wheel 8 Hydraulic elevating mechanism 14 Ground work machine (rotary tilling device) 27 Control device 46 Ascent proportional control valve 47 Ascent proportional control valve

Claims (1)

(57) [Claims] 1. An inclination detector 16 for detecting an inclination of the body 1 in the horizontal direction, an attitude changing means 15a for changing an inclination attitude of a ground working machine 14 connected to the aircraft 1, an aircraft 1 and a ground working machine. And a stroke detector 17 for detecting a relative angle difference between the ground work machine 14 and the ground work machine 14 at a predetermined angle by operating the attitude changing means 15a when the body 1 is tilted in the horizontal direction. In the rolling control device for a ground working machine, the target of the attitude changing means 15a calculated based on the value detected by the tilt detector 16 and the set value set by the tilt setter 18 is provided. The stroke value and the stroke of the attitude changing means 15a immediately before the body 1 starts to tilt.
A rolling control device for a ground working machine, which averages a difference from the ground value and controls the posture changing means 15a to expand and contract using the average value as a control target value.