JPH0614608A - Lifting and lowering controller of tiller - Google Patents

Abstract

PURPOSE:To obtain a tilling depth controller capable of preventing lowering of operation efficiency by engine stop, etc., even if a field is slurry. CONSTITUTION:The objective controller controls a lift cylinder CY so that detection value of true tilling depth sensor PM1 for detecting true tilling depth based on angle displacement of a back cover of a rotary tiller may be made to coincide with a get objective tilling depth by a tilling depth controller PM2 and operates difference between the number of revolutions of an engine changed, according to tilling operation and a standard number of revolutions and its changing ratio, judging a detection value of number of revolutions of engine obtained when a rotary tiller is lowered to a prescribed tilling depth as the standard number of revolutions and corrects value of a set objective tilling depth and true tilling depth based on previously set map data from the operated difference and the changing ratio and carries out tilling depth control based on the corrected new data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is constructed such that a rotary tiller is connected to a traveling body so as to be lifted and lowered, and a rotary arm is vertically moved by a lift arm which is lifted and lowered by a lift cylinder. Tillage equipped with tillage depth control means for controlling the lift cylinder so that the detection value of the actual tillage depth detection sensor that detects the actual tillage depth based on the angular displacement of the cover and the set target tillage depth set by the tiller depth setting device match. The present invention relates to a lifting control device.

[0002]

2. Description of the Related Art In the lifting control device for the above tiller,
Conventionally, as disclosed in, for example, Japanese Unexamined Patent Publication No. 4-75504, there is one configured to correct the detected actual tillage depth by using the detection value of the actual tillage depth detection sensor when the tiller is lifted and raised as a reference value. there were.

[0003]

In the above-mentioned conventional structure, even if the soil scraped up by the tilling claws adheres to the rear cover at the position where the lower swing limit of the rear cover is different during the tilling work,
By correcting the detection value of the tilling device in the suspended state as a reference, it is possible to always detect the actual cultivation depth. However, in the above-described conventional structure, since the plowing depth control is always performed based on the detected value of the rocking angle associated with the grounding of the rear cover, for example, the field is mud and the rear cover of the tiller together with the wheels of the traveling machine body. It may also sink into a weak field scene, and it may not be possible to accurately detect the actual cultivation depth. Then, the detection value of the actual tillage depth detection sensor does not match the set tillage depth, and the tiller continues to descend, which may cause an excessive work load on the engine and cause the engine to frequently stop. There was a problem that the efficiency decreased. The present invention aims to eliminate the above-mentioned problems.

[0004]

According to a characteristic configuration of the present invention, in the elevator control device for a tilling device described at the beginning, an engine speed detecting means for detecting a rotating speed of an engine mounted on a traveling body and a rotary tilling device are provided. The engine rotation speed detection value when descending to a predetermined tillage depth is used as a reference rotation speed, and a calculation unit that calculates a difference and a change rate between the engine rotation speed and the reference rotation speed that change with cultivating work, From the calculated difference and the rate of change, based on map data determined in advance, the value of the set target plowing depth or the actual plowing depth is corrected, and the plowing depth control means is based on the corrected new data. It is configured to execute control.

[0005]

Operation: A standard engine speed is set as a reference speed when the rotary tiller is lowered to a predetermined tillage depth, and a change amount and a change rate of the engine speed from the reference speed are calculated to calculate the engine. It is unnecessary even if the rear cover sinks, etc., by determining the drive condition of the rear cover and correcting the value of the set target plowing depth or the actual plowing depth, which is the reference of the plowing depth control according to the state change. It is possible to prevent the engine from stopping by preventing the downward movement of the simple tilling device.

[0006]

[Effects of the Invention] Therefore, even if there is a mud in the middle of the field, the plowing device prevents the sinking engine from overloading the engine, and the engine is frequently stopped. As a result, it is possible to suppress the adverse effects such as a decrease in work efficiency.

[0007]

Embodiments will be described below with reference to the drawings. Figure 8
Shows a riding-type cultivator. In this cultivator, a rotary cultivating device 2 is movably connected to a rear portion of a riding type traveling body via a link mechanism 1 so that a cultivating work in a field can be performed while operating the traveling body. This tiller is configured to automatically control the tilling depth by the rotary tiller 2, that is, the actual tilling depth so as to maintain the set value. That is, the left and right links 3 in the link mechanism 1 are lifted via the lift rod 5 by the lift arm 4 which is driven to move up and down around the horizontal axis by the lift cylinder CY,
The cultivating device 2 is configured to be driven up and down, and the rear cover 6 of the cultivating device 2 is attached to the rotary cover body 7.
Is pivotally connected about the axis of the horizontal axis so that the relative vertical movement amount of the rear cover 6 due to the plowing of the tilling claw 2a into the soil is detected by the potentiometer-type cover angle sensor PM1 as the actual plowing depth. The electromagnetic hydraulic control valve V for the lift cylinder CY is controlled to maintain the actual tillage depth at the set value so that the detected value by the cover angle sensor PM1 matches the set tillage depth manually set by the potentiometer-type tiller depth setter PM2. It is configured to do. In addition, an elevating lever 8 for artificially switching the plowing device 2 between a lowered plowing working position and a significantly raised non-working position is provided.
A potentiometer type lift arm angle sensor PM3 for detecting the relative angle of the lift arm 4 to the machine body is provided. In the operation of the plowing depth control, when the field is mud or the like and the wheels of the traveling vehicle body are submerged in the soil and the subcover 6 is also submerged, the engine is unnecessarily submerged. It is configured so that the stoppage can be prevented. More specifically, as shown in FIG. 1, the electromagnetic hydraulic control valve V is composed of an electromagnetic proportional flow rate control valve whose opening can be proportionally changed and controlled according to the amount of supplied current. A rotation speed detection sensor S configured to be driven and controlled by a control device 9 including a microcomputer and for detecting an output rotation speed of an engine 10 mounted on a traveling machine body.
An example of the rotation speed detection means is provided, and the output of the rotation speed detection sensor S is also provided to the control device 9. Then, the control device 9 uses the engine speed detection value when the cultivating device 2 descends to the set target tillage depth as a reference speed, and the engine speed and the reference speed that change with the tilling work. A calculation means A for calculating a difference and a rate of change and a set target tillage depth by a tilling depth setting device are corrected based on map data determined in advance from the difference and the rate of change calculated by the means for correction A, and correction is made. On the basis of the new data obtained, the cover angle plowing depth control means B for controlling the lift cylinder so that the corrected target plowing depth and the actual plowing depth match is provided in a control program format. Control is executed as follows. As shown in FIGS. 4 and 5, when the elevating lever 8 is in the raised position, the elevating lever 8 is maintained in the raised position, and when the tiller 2 is in the raised position.
Is operated to the lowered position, the plowing depth setting device PM at that time
2 output b [set target tillage depth], output a of cover angle detection sensor a [actual tillage depth], output of lift arm angle sensor PM3 and output of engine speed sensor S, and lift cylinder CY is lowered. Let [Step 1
4]. At this time, the descending speed is proportionally controlled so as to be a speed corresponding to the amount of deviation between the target tillage depth a and the actual tillage depth b. Then, the lowering speed immediately before the cultivating device 2 comes into contact with the ground is judged by the lift arm angle, and the cultivating device is slowly grounded down at a lowering speed that is slower than the speed based on the proportional control. Based on the above, the descending speed is controlled to prevent the engine from being stopped by the characteristic determined in advance according to the amount of change and the rate of change of the detected rotation speed [steps 5 and 6]. When the actual cultivation depth a detected by the cover angle detection sensor PM1 matches the target cultivation depth b, the descending operation is stopped [steps 7 and 8], and the engine speed at that time is stored in the memory 11 as the reference speed NE. [Step 9]. When the detected rotation speed at this time is a low rotation speed just before the engine stops, the preset minimum rotation speed is stored as the reference rotation speed. Then, the difference between the engine speed N at that time and the reference speed NE (NE-
N) and the rate of change dN / dt are calculated [Step 1
0], the correction amount Δb of the set target plowing depth b is calculated from the calculated difference and the rate of change based on predetermined map data [step 11]. The map data at this time is set by so-called fuzzy control. Next, the value b1 after correcting the set target tillage depth by the correction value Δb calculated as described above is set as a new target tillage depth [step 12], and based on this new target tillage depth b1. The lift cylinder CY is vertically controlled [steps 13 to 15]. That is, the electromagnetic control valve V is determined based on the map data of the deviation-flow rate map and the flow rate-current map so that the flow rate having an operating speed proportional to the deviation between the detected actual cultivation depth and the corrected target cultivation depth is supplied. Supply the electric current. When the traveling clutch is disengaged during the tilling work in which such control is performed, and this is detected by the clutch detection switch SW, the clutch disengagement operation is performed until the clutch disengagement operation is performed again. The lift arm angle is maintained and fixed [steps 16 and 17]. When the accelerator lever 12 is changed and operated by the accelerator lever detection sensor PM4 on the way, the lift arm angle at the time of the operation is maintained until the sensor detection value reaches a stable value. If the sensor detection value becomes stable,
From the mechanical characteristics of the displacement amount of the accelerator lever 12 and the no-load rotational speed determined in advance, the difference between the initial no-load rotational speed N0 and the no-load rotational speed N1 after the changing operation is subtracted from the reference rotational speed NE to obtain a new value. It is corrected as the reference rotation speed [steps 18 to 21]. Then, such control is maintained until the raising operation is performed on the headland, and when the raising operation is performed [step 22], a new reference rotational speed NE is reset and such control is executed.

In this cultivator, instead of the operation of controlling the working depth by the rear cover 6 as described above, the working depth can be controlled even when the rear cover 6 is largely retracted upward and not in use. is there. More specifically, when the rear cover 6 is not used, the rear cover 6 is largely lifted and pinned and held in position as shown by a phantom line in FIG. At this time, the cover angle detection sensor PM1 has an output that greatly deviates from the normal operating range in the cover angle plowing depth control described above. Therefore, when the detected value is larger than the set value e, the engine rotation control as described below is performed. State, and when it is smaller than the set value e, switching means C for automatically switching so as to set the cover angle plowing depth control state as described above.
Is provided in the controller 9 [see step 00 in FIG. 2]. The engine rotation control means D is provided in the control device 9 in the form of a control program, and the control device 9 controls as follows. As shown in FIG. 6 and FIG. 7, when the elevating lever 8 is operated to descend, the target tillage depth by the tiller depth setting device PM2 is read, and the lift arm angle d (target lift arm angle) corresponding to this target tiller depth is read. Calculate [Steps 1 to 4]. Next, the outputs of the lift arm angle detection sensor PM3 and the engine speed detection sensor S are read, and the tiller 2 is operated to descend [steps 5 and 6]. At this time, the descending speed is proportionally controlled so as to be a speed corresponding to the amount of deviation between the target tillage depth and the actual tillage depth. Then, the lowering speed immediately before the cultivating device 2 comes in contact with the ground is judged by the lift arm angle, and the cultivating device 2 is slowly grounded down at a lowering speed than the speed based on the proportional control, and after the grounding, the engine speed is detected. Based on the result, the descending speed is controlled to prevent the engine from stopping according to the characteristic determined in advance in accordance with the change amount and the change rate of the detected rotation speed [steps 7 and 8]. When the detected value c of the lift arm angle detection sensor PM3 matches the target lift arm angle d, the descent is stopped, and the engine speed at that time is stored in the memory 11 as the reference speed NE [steps 9 to 11]. . Then, along with the tilling work, the difference (NE-N) between the engine speed N at that time and the reference speed NE and the change rate dN / dt at every predetermined time.
And [step 12], and the calculated difference (NE
-N) and the rate of change dN / dt are used to calculate the correction amount Δd of the set target plowing depth d based on predetermined map data [step 13]. The map data at this time is set by so-called fuzzy control. Next, the value d1 after correcting the target lift arm angle by the correction value Δd calculated as described above is set as a new target lift arm angle [step 12], and the lift is performed based on this new target value. Control the cylinder CY up and down [Steps 15-1
7]. Then, the same clutch control and accelerator lever control as those in steps 16 to 21 of the cover angle control as described above are executed [steps 18 to 23], and such control is maintained until the raising operation on the headland is performed. Then, when the ascending operation is performed [step 24], a new reference rotational speed is reset and such control is executed.

It should be noted that although reference numerals are given in the claims for facilitating the comparison with the drawings, the present invention is not limited to the configuration of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a control block diagram.

[Fig. 2] Switching control flowchart

[Fig. 3] Control characteristic diagram

[Fig. 4] Cover angle plowing depth control flowchart

FIG. 5: Cover angle plowing depth control flowchart

FIG. 6 is an engine speed control flowchart.

FIG. 7 is an engine speed control flowchart.

[Figure 8] Overall side view of the cultivator

[Explanation of symbols]

 2 Rotary tiller 4 Lift arm 6 Rear cover 10 Engine A Calculation means B Cultivation depth control means CY Lift cylinder N Engine rotation speed NE Reference rotation speed NE-N Rotation speed difference dN / dt Change rate PM1 Actual cultivation depth detection sensor PM2 Tillage Depth setting device

Claims (1)

[Claims] 1. A rotary tiller (2) is movably connected to a traveling machine body, and a rotary arm (4) is vertically moved by a lift cylinder (CY) to drive the rotary tiller (2) up and down. , The detection value of the actual tillage depth detection sensor (PM1) for detecting the actual tillage depth based on the angular displacement of the rear cover (6) of the rotary tiller (2) and the set target tillage depth by the tillage depth setter (PM2). Tillage depth control means (B) for controlling the lift cylinder (CY) so that
An elevation control device for a tiller equipped with an engine rotation speed detecting means (S) for detecting a rotation speed of an engine (10) mounted on a traveling body, and a rotary tiller (2) descending to a predetermined tillage depth. The engine rotation speed detection value at the time of performing is set as a reference rotation speed (NE), and a difference between the engine rotation speed (N) and the reference rotation speed (NE-N) that changes with cultivating work.
And a rate of change (dN / dt), and a calculating means (A) for calculating the difference (NE-N) and the rate of change (dN / dt) calculated based on map data determined in advance. , The value of the set target tillage depth or the actual tillage depth is corrected,
An elevating control device for a tilling device, wherein the tilling depth control means (B) is configured to execute control based on the corrected new data.