JP2696422B2 - Tillage control device for ground work vehicle - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a tillage depth control device for a ground working vehicle such as a tractor.

[Problems to be Solved by the Related Art and the Invention] Generally, in this type of ground work vehicle, a rear cover provided in a tilling work section maintains a target swing angle determined based on a set value of a cultivation depth setting device. There is a type that performs so-called automatic plowing depth control for raising and lowering the tillage working unit, but in such a case, the ground contact posture (target swing angle) of the rear cover greatly changes between shallow plowing and deep plowing. There was a fear that the work accuracy could vary greatly depending on the setting range of the tillage setting device.

Therefore, there is an attempt to automatically control the vertical movement of the rear cover based on the setting value of the tillage depth setting device so that the rear cover maintains an appropriate grounding posture. Conventionally, however, as shown in Fig. 11, the entire setting range of the tillage depth setting device and the entire moving range of the rear cover are directly associated with each other. The attitude (target swing angle) changed, and as a result, it was not possible to perform stable tillage work with high work accuracy.

[Means for Solving the Problems] The present invention has been created with the object of providing a plowing depth control device for a ground working vehicle that can eliminate these disadvantages in view of the above-described circumstances. And a rear cover target value determining means for determining a target vertical position and a target swing angle of the rear cover based on the set value of the tillage depth setting device for setting the tillage depth in the tillage depth automatic control unit, In a ground working vehicle configured to control a vertical movement mechanism of a rear cover and a working unit elevating mechanism based on a vertical position and a swing angle, the target value determination unit includes a setting value of a tillage depth setting device. It is determined which of the preset range of the shallow tillage range, the middle tillage range, and the deep tillage range is set based on the predetermined range. When By moving the corresponding vertical movement range, the target vertical position is determined so that the target swing angle value of the automatic plowing depth control becomes a constant value. It is characterized in that target vertical position determining means for determining a shallow position or a deepest position is provided.

According to the present invention, the work accuracy can be improved by this configuration.

Example Next, an example of the present invention will be described with reference to the drawings. In the drawings, reference numeral 1 denotes a traveling body of an agricultural tractor, and a rotary tilling type working unit 3 is connected to a rear part of the body 1 via a lifting link mechanism 2 so as to be able to move up and down. The basic configuration, such as raising and lowering by swinging the lift arm 5 accompanying the expansion and contraction operation of the hydraulic cylinder 4, is the same as the conventional one.

Reference numeral 6 denotes a main cover of the working unit 3. The main cover 6 is formed in an arc shape so as to cover a tilling claw 8 attached to a tilling claw shaft 7. A pair of left and right roller brackets 10 to which the guide rollers 9 are mounted are fixedly provided.

On the other hand, reference numeral 11 denotes a rear cover provided at the rear end of the working section 3. The rear cover 11 is attached to a support shaft 12 so as to be vertically swingable, and is constantly urged toward the field by a bullet 11a. , And a tillage detection sensor (rear cover 11
The pivot 12 is connected to a potentiometer 16 for detecting the tillage depth based on the swing angle of the main cover 6. The support shaft 12 is curved in an arc shape so as to follow the peripheral surface of the main cover 6, and has a substantially cross-sectional shape. A pair of guide rails 12a formed in a U-shape are fixedly provided, and these guide rails 14
, Respectively. In other words, the rear cover 11 is movable along an arc having the tilling claw shaft 7 substantially at the center, and moves from the shallow cultivation posture moved forward to the deep cultivation posture moved backward to establish an appropriate grounding posture. Can be maintained.

Reference numeral 14 denotes an electric cylinder attached to the top mast 15 of the working unit 3. The electric cylinder 14 operates the rear cover 11 (support shaft 12) to which the tip is pivoted by an operation command from a control unit 16 described later. It is made to move by expansion and contraction operation based on.

Reference numeral 17 denotes a side panel provided on the side of the driver's seat. The side panel 17 includes a lifting operation lever 18, a lifting operation switch 19, a plowing depth automatic switch 20, a plowing depth setting volume 21, and a rear cover. Various operating tools such as an automatic switch 22 are provided.

The control unit 16 is a control unit configured by using a so-called microcomputer (CPU, ROM, RAM) or the like. The control unit 16 includes the cultivation depth detection sensor 13, the lifting / lowering operation switch 19, the cultivation depth automatic switch 20, and the like. Tillage setting volume (tillage setting device) 2
1, Rear cover manual switch 22, Cylinder length sensor 23 for detecting the most contracted state of electric cylinder 14, Lifting lever 18
A signal is input from a lever angle sensor 24 or the like that detects the front-back swing angle, and an operation command is output to the hydraulic cylinder 4, the electric cylinder 14, and the like based on the determination based on these input signals. That is, the control unit 16 performs rear cover movement control and plowing depth automatic control described later.

The rear cover movement control is performed by determining a target vertical position of the rear cover 11 based on the set value of the plowing depth setting volume 21 and extending and retracting the electric cylinder 14 based on a comparison between the target vertical position and the detected position. 11 is moved to an appropriate position. In the determination of the target vertical position, as shown in FIG. 9, the setting range of the cultivation depth setting volume 21 is set to a shallow cultivation range based on the set value. When the set value of the tillage setting volume 21 is within the shallow tillage range or the deep tillage range, the target vertical position is determined as the shallowest position and the deepest position, respectively. When the set value is within the middle cultivation range that is frequently used, the target vertical position of the rear cover 11 is determined based on the magnitude of the set value. That is, the rear cover 11 can be moved up and down only in the middle tillage range. However, since the up and down movement range of the rear cover 11 matches the middle tillage range, the target sensor value (rear cover 11 Without changing the target swing angle), a predetermined suitable value can be determined as shown in FIG.

In the vertical movement control of the rear cover, in addition to the automatic movement control of the rear cover 11, a manual control for moving the rear cover 11 by the expansion and contraction operation of the electric cylinder 14 based on the operation of the rear cover manual switch 22 is performed. The automatic control of the rear cover 11 is not executed only by the ON operation of the automatic depth control switch 20. That is, in the rear cover movement control, it is first checked whether the automatic cultivation depth switch 20 is ON. If the switch is ON, subsequently, the automatic cultivation depth switch 20 is turned ON, and then the lifting operation lever 18 is turned ON.
It is determined whether or not the lifting operation or the operation of the tillage setting volume 21 has been performed, and the automatic control of the rear cover 11 is permitted only when this determination is YES. Also, in the automatic control state of the rear cover 11, when the rear cover manual switch 22 is operated, the rear cover 11 is moved based on the operation of the rear cover manual switch 22, but the rear cover is released in this case. The automatic control 11 is re-executed based on the fact that the plowing depth setting volume 21 has been operated by a predetermined amount or more after the cancellation.

On the other hand, the automatic plowing depth control determines a target sensor value (target swing angle of the rear cover 11) A based on the set value of the plowing depth setting volume 21, and the target sensor value A and the plowing depth detection sensor 13 are determined.
The working unit 3 is moved up and down by extending and retracting the hydraulic cylinder 4 based on the comparison with the sensor detection value B of the target sensor value B. The target sensor value A is set in the tillage setting volume 21 in the shallow tillage range. If it is within the deep tillage range, it is determined to be a value that changes with a change in the set value, while if the set value is within the middle tillage range, it is set to a predetermined value as described above. Is to be decided.
In the automatic plowing depth control of the embodiment, a normal deviation control for switching the operating speed of the hydraulic cylinder 4 based on the difference between the target vertical position of the rear cover 11 and the detected position is performed.

In the embodiment of the present invention configured as described above, when the automatic cultivation depth switch 20 is turned on and the desired cultivation depth is set by the cultivation depth setting volume 21, the rear cover 11 is maintained at the target swing angle. Automatic plowing depth control for raising and lowering the working unit 3 and rear cover 11 so as to maintain a proper grounding posture
When the cultivation depth setting volume 21 is set in the middle cultivation range where the setting frequency is high, the rear cover 11 moves in the vertical movement range that coincides with the middle cultivation range. This allows the target sensor value A in the deep automatic control to be a constant value. In other words, the rear cover is
It is possible to maintain a suitable grounding posture without changing the grounding posture of the eleventh embodiment.

As described above, in the embodiment in which the present invention is implemented, while controlling the movement of the rear cover 11 to maintain the grounding posture of the rear cover 11 at the proper posture during the automatic plowing depth control, the plowing depth setting volume is controlled. In the medium tilling range where the setting frequency is high in 21, the target sensor value A of the automatic tilling depth control is a constant value. Accordingly, the rear cover 11 does not change the grounding posture in the middle tillage area as in the past, but always maintains the optimum grounding posture and performs highly accurate tillage depth detection operation. The work accuracy in can be improved.

Further, the plowing depth control in the deep plowing range or the shallow plowing range is performed by the rear cover 11 located at the upper or lower limit position.
As a result, in this range, when the tillage depth setting volume 21 is operated, the tillage depth automatic control is performed not by the vertical movement of the rear cover 11 as in the middle tillage range but by the change of the target sensor angle A. However, the tillage depth detection is performed by the rear cover 11 already located at the upper or lower limit position more suitable as the tillage depth detection position of deep plowing or shallow plowing, so that the accuracy of tillage depth detection can be improved.

Moreover, with the improvement in the accuracy of the tillage depth detection, the actual change in the tillage depth with respect to the change in the set value of the tillage depth setting volume 21 is also equalized, so that the tillage depth can be set with high accuracy.

Furthermore, in this case, since the rear cover 11 rises to the upper limit position at the boundary position between the middle cultivation range and the deep cultivation range, the power loss can be reduced by reducing the rotation of the mud by the rear cover 11.

[Effects] In summary, since the present invention is configured as described above, in the automatic plowing depth control state, the rear cover is controlled to move so that the rear cover maintains a proper grounding posture. When the setting value of the setting device is a middle cultivation range where the setting frequency is high, the rear cover is moved in a vertical movement range that coincides with the middle cultivation region, so that the target swing angle value of the automatic plowing depth control becomes a constant value. Is decided, shallow tillage,
In the deep tillage range, the plowing depth automatic control is performed by changing the target swing angle, and in the middle tillage range, the plowing depth automatic control is performed by changing the target vertical position without changing the target swing angle.

As a result, the vertical movement range of the rear cover does not need to be forcibly increased as in the case of including the shallow tillage and the deep tillage range. There is no need to increase the vertical movement stroke of the, and there is no simplification of the structure.In addition, especially in the middle cultivation range where the setting frequency is important, accurate cultivation depth detection operation is performed, Accuracy can be improved.

In addition, since the rear cover is raised to the upper limit position in the deep cultivation range, the power loss can be reduced by reducing the rotation of mud by the rear cover.

In addition, tillage control in the deep tillage or shallow tillage range,
As a result of the rear cover already located at the upper or lower limit position, in these ranges, when the tillage depth setting device is operated, the plowing depth is automatically controlled by changing the target swing angle, while Alternatively, the cultivation depth detection is performed by the rear cover located at the upper or lower limit position more suitable as the cultivation depth detection position for shallow cultivation, thereby improving the cultivation depth detection accuracy.

[Brief description of the drawings]

The drawings show an embodiment of the tillage depth control device in the ground work vehicle according to the present invention, wherein FIG. 1 is a side view of a tractor, FIG. 2 is a plan view of the same, and FIG. FIG. 4 is a block diagram of a control mechanism, FIG. 5 is a flowchart of rear cover movement control, FIG. 6 is a flowchart of automatic plowing control, FIG. 7 is a front view of a plowing depth setting volume, FIG. 8 is a graph showing the relationship between the tillage depth setting value and the target sensor value, FIG. 9 is a graph showing the relationship between the tillage depth setting value and the vertical position of the rear cover, and FIG. 10 is a graph showing the relationship between the tillage depth setting value and the actual tillage depth. FIG. 11 is a graph showing the relationship between the conventional tillage depth set value and the target sensor value, and FIG. 12 is a graph showing the conventional relationship between the tillage depth set value and the rear cover position. In the figure, 1 is a traveling body, 3 is a working unit, 4 is a hydraulic cylinder,
11 is a rear cover, 14 is an electric cylinder, 16 is a control unit, 18 is an elevating operation lever, 20 is an automatic switch for cultivation depth, and 21 is a volume for setting the cultivation depth.

Claims (1)

(57) [Claims] A cultivation depth automatic control unit includes: a rear cover target value determination unit that determines a target vertical position and a target swing angle of a rear cover based on a setting value of a cultivation depth setting device that sets a tilling depth. A ground work vehicle configured to control a vertical movement mechanism of a rear cover and a working unit elevating mechanism based on the determined vertical position and swing angle,
In the target value determination means, it is determined which of the preset range of shallow tillage range, medium tillage range, or deep tillage range is set based on the set value of the tillage depth setting device, and the determined set range is In the middle cultivation range where the setting frequency is high, the rear cover moves the up and down movement range that coincides with the middle cultivation range, and determines the target vertical position so that the target swing angle value of the automatic plowing depth control becomes a constant value. A plowing depth control device for a ground work vehicle, comprising target vertical position determining means for determining the target vertical position of the rear cover to be the shallowest position or the deepest position when the range is the plowing range or the deep plowing range.