JPH0799807A - Device for controlling tillage depth detection sensitivity in rotary tilling machine - Google Patents

Abstract

PURPOSE:To approximately constantly maintain the detection sensitivity of a tillage depth on the tilling operation of a rotary tiller. CONSTITUTION:A rotary tiller 2 is lifted or lowered through a hydraulic mechanism 5 for the vertical movement to constantly control the depth of tilling. A tilling cover 13 is disposed round a horizontal tilling tine shaft 9 in a state capable of freely adjusting a rotation position with a hydraulic cylinder 22. A rear cover 21 whose lower end site can contact with the surface of a field is vertically rotatably mounted on the rear end of the tilling cover 13. A controller 33 is disposed so that the depth of tilling is constantly held on the basis of the detection value of an angle sensor 33 for detecting the rotation angle of the rear cover 21. The hydraulic cylinder 22 is operated so that the tilling cover 13 is rotated in the direction to reduce a traction load in response to a load sensor 31 for detecting the traction load, and the controller 30 controls to correct the sensitivity of tilling depth detection on the basis of the detection value of the angle sensor 33.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting sensitivity of tilling depth in a rotary tiller driven and driven by a traveling vehicle such as a tractor.

[0002]

2. Description of the Related Art In this type of rotary cultivator, a rotary cultivator is connected to a traveling vehicle so as to be vertically movable in order to adjust the cultivating depth. And, conventionally,
As disclosed in JP-A-27165, a plowing cover body that covers the upper side of the outer circumference of the rotary locus of the plowing pawl in a rotary tiller is attached so as to be rotatable around a horizontal plowing pawl axis. , The rear end of the tilling cover is connected to a rear cover which can be turned up and down and can be brought into contact with the field under a predetermined pressure, while the tilling cover is turnable and its turning position is adjusted and held. Therefore, the bottom surface (inner surface) of the tillage cover body can be changed according to the field conditions (softness and stickiness of soil).
It is known to perform plowing work smoothly while preventing clogging between the rear portion and the lower surface (inner surface) of the rear cover and the upper rear portion of the outer circumference of the rotation path of the plowing claws. It is also known to use the rear cover as a plowing depth detector.

In this case, when the rotary tiller is rotated up and down to change the tillage depth, there is an inconvenience that the rotating posture of the tiller cover body is also changed.
As disclosed in Japanese Patent Laid-Open No. 2-87004, a rotary hydraulic cylinder is interposed between the frame of the rotary cultivator and the cultivating cover body, and the cultivating cover body detects an angle with respect to the horizontal. The angle sensor is provided, and the turning hydraulic cylinder is operated according to the detection value of the angle sensor. Thus, it has been proposed that when the rotary tiller moves up and down to adjust the tillage depth, the tiller cover body can always be held at a constant position (posture) with respect to the field scene. .

[0004]

By the way, as a means for detecting the tilling depth of a rotary tiller, a rear cover which can be vertically rotated at the rear end of the tiller cover body and can be brought into contact with a field scene at a predetermined pressure is provided. It is most effective to detect the plowing depth by connecting and detecting the rotation angle of the rear cover to convert the height between the lower end of the outer circumference of the rotation path of the plowing claw and the field scene after plowing. It is considered to be direct and highly reliable.

However, as shown in FIG. 8, since the lower end of the rear cover 100 is usually extended rearward and downward in the traveling direction of the rotary cultivator, the cultivating cover body 101 itself as described above. Is rotated around the pawl shaft 102 to which the plowing pawl 104 is attached.
When the position (height position) of the pivot point 103 between 00 and the tilling cover body 101 changes, the change value Δθ of the rotation angle of the rear cover 100 with respect to the change value ΔH of the tilling depth H also changes.

For example, the higher the pivot point 103 is (the larger the inclination angle of the rear cover 100 with respect to the horizontal), the rear cover 10 with respect to a predetermined tilling depth variation value ΔH.
The fluctuation value Δθ of the turning angle of 0 is large, in other words, the fluctuation value Δθ of the turning angle of the rear cover 100 is large with respect to the small fluctuation of the plowing depth, so that the sensitivity of the rear cover 100 for detecting the plowing depth becomes high. . Since the sensitivity becomes dull as the pivot point 103 comes to a lower position, if the controller controls the plowing depth based only on the fluctuation value of the rotation angle of the rear cover 100, the pivot point becomes There is a problem that stable control cannot be realized because the detection sensitivity for the control for keeping the plowing depth constant differs depending on the height of the point.

In particular, when the soil quality of the field fluctuates in the middle of the plowing work, the turning position of the plowing cover body is arbitrarily changed in order to reduce the traction load by removing the soil clogged on the lower surface side of the plowing cover body. Then, the sensitivity of the rear cover for detecting the tilling depth fluctuates, and stable constant tilling depth control cannot be performed. The present invention has been made to solve this problem, and an object of the present invention is to provide a device for detecting the sensitivity of detecting the depth of tillage in a rotary tiller, which has a stable detection sensitivity.

[0008]

To achieve the above object, a plowing depth detecting sensitivity adjusting device in a rotary tiller according to the present invention is connected to a traveling vehicle equipped with an engine so as to be adjustable in vertical movement and towed. In the rotary cultivator that is driven, the cultivating cover body in the rotary cultivator is provided by the drive actuator so that the rotary position can be adjusted around the horizontal cultivating claw axis, and the rear end of the cultivating cover body, A rear cover whose lower end portion can be grounded in a field is rotatably mounted, and an angle sensor for detecting a rotation angle of the rear cover is provided between the tillage cover body and the rear cover. Provided with a control device that controls so as to keep the tilling depth constant by the detected value, according to the detected value of the load sensor that detects the traction load,
While the drive actuator is operated to rotate the tilling cover body in the direction in which the load is reduced, the control device controls so as to correct the tilling depth detection sensitivity based on the detection value of the angle sensor. .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described. FIG. 1 shows a tractor 1 with an engine 3 (see FIG. 4) as a traveling vehicle and a tractor 1 which is vertically movable via a link mechanism 4. The side view of the rotary cultivator 2 towed by FIG. At the rear end of the tractor 1, a link mechanism 4 is moved up and down via a lifting hydraulic mechanism 5 and a lifting link 6 to drive the rotary cultivator 2 up and down with respect to the tractor 1. Hydraulic pressure is supplied to the lifting hydraulic mechanism 5 and the like from a hydraulic pump (not shown) that is rotated by the driving force of the engine 3. Further, while the tractor is moved forward and backward via the transmission (transmission mechanism) 7 by the power from the engine 3, the PTO extending rearward from the rear end of the tractor 1
Rotary cultivator 2 described later via the shaft 8 and the universal joint shaft
Is transmitted to the horizontal tiller shaft 9.

As shown in FIGS. 2 and 3, the rotary cultivator 2 is provided with a horizontally long cylindrical main beam 11 attached to a frame 10 and both left and right ends (or one side end) of the main beam 11. Chain case 12 and tillage cover body 13
And the like, and the power from the PTO shaft 8 is transmitted to the shaft in the gear case 14 at the left and right central portions of the main beam 11,
From the transmission shaft 15 in the main beam 11 to the chain case 12
Power is transmitted to the cultivating claw shaft 9 through the inner chain 16 to rotate the claw body 17 clockwise in FIG.

The tilling cover body 13 is formed so as to cover the upper part of the outer peripheral end of the rotation locus of the pawl body 17 which is radially and removably attached to the tilling claw shaft 9 so as to cover the upper side. The base ends of the side covers and arms 18 and 18 extending downward from the left and right ends are rotatably fitted to the outer circumferences of bearings 19 and 19 that pivotally support the left and right ends of the plowing claw shaft 9. .

A pivot shaft 2 is provided at the rear end of the tilling cover body 13.
A rear cover 21 is mounted so as to be vertically rotatable around 0, and the rear cover 21 is usually formed of hard rubber. The frame 10 and the cultivating cover body 13 are mounted via a rotating hydraulic cylinder 22 as a drive actuator, and the extension of the hydraulic cylinder 22 causes the cultivating cover body 13 to rotate rearward and to move forward when contracted. On the other hand, the rear cover 21 comprises a frame 1 and a hanger rod 23 whose spring force can be adjusted by the springs 24 and 25.
Are connected via.

FIG. 4 is a functional block diagram of the control system of the present invention. The main control device 30 is an electronic device such as a microcomputer, and a CPU for executing calculation and control.
(Central processing unit), read-only memory (ROM) storing control program and fixed data, readable / writable memory (R) for temporary storage of various data
AM), interface, etc.

At the input portion of the control device 30, a detection signal of a load sensor 31 for detecting the pulling load of the rotary tiller 2 and a cover position detector 32 for detecting the rotating position of the tiller cover body 13 are provided. Of the angle sensor 33 such as a rotary encoder for detecting the rotation angle of the rear cover 21 and the signal of the tilling depth setting device 34.

At the output of the controller 30, a drive circuit for the electronic governor 35 for adjusting the amount of fuel injected into the engine 3 in the tractor and a drive actuator for adjusting the rotating position of the tiller cover body 13 are provided. A control valve (not shown) of the turning hydraulic cylinder 22 is connected to output a command signal. The load sensor 31 may detect the position of the injection amount adjusting rack in the electronic governor 35 for adjusting the amount of fuel injected into the engine 3, as shown in the present embodiment, or may be a rotary cultivator. It may be a load cell provided in the link mechanism 4 that pulls the two. The cover position detector 32 for detecting the rotating position of the tilling cover body 13 uses a direct-acting position scale provided between the cylinder portion of the rotating hydraulic cylinder 22 and the piston rod.

When plowing, the plowing depth setting device 34 is used.
Set the value of the predetermined plowing depth by operating the input with the dial etc. With the turning position of the tilling cover body 13 in the standard position, the lower end portion of the rear cover 21 rotatably attached to the rear end of the tilling cover body 13 and the tilling claw body 1
The height dimension with respect to the lower end of the rotation locus of 7 is the value of the plowing depth, and the lifting hydraulic mechanism 5 is operated so that the plowing depth becomes a predetermined value.

Therefore, the rear cover 21 serves both as a detector of the plowing depth and a function of smoothing the tilled field scene, and the angle sensor 33 is attached to a pivot shaft pivotally supporting the base end of the rear cover 21. Is attached, and when the detected value of the angle sensor 33 is a predetermined value (reference value), it is recognized as a predetermined plowing depth. Then, the rear cover 21 is frequently moved up and down on a fine uneven surface in the field scene that has been cultivated, so that the lifting hydraulic mechanism 5 does not cause a hunting phenomenon.
When the detection value of the angle sensor 33 is in a certain angle range across the reference value, it is not a dead zone for prohibiting the operation of the lifting hydraulic mechanism 5, and when it deviates from this dead zone, the lifting hydraulic mechanism 5 is lifted. Is operated to control the height position of the rotary cultivator 2 to a predetermined value.

By the way, as described above, the traction force (load) may increase due to clogging of the cultivated soil on the inner surface of the cultivating cover body 13 depending on the field conditions. It is necessary to change the position of the cover body 13. Then, the position (height dimension L, see FIG. 4) of the pivot point 20 (angle sensor 33) between the rear cover 21 and the cultivating cover body 13 varies, and the rear cover 21 rotates with respect to the variation value ΔH of the plowing depth H. Angle fluctuation value Δθ
Also fluctuates.

As can be understood from FIG. 4, for example, the higher the pivot point 20 is (the larger the L value is) (the smaller the inclination angle of the rear cover 21 with respect to the vertical line is), the more the fluctuation value of the predetermined tilling depth is obtained. The variation value Δθ of the rotation angle of the rear cover 21 with respect to ΔH is large, in other words, the variation value Δθ of the rotation angle of the rear cover 21 is large with respect to a small variation of the plowing depth, so that the plowing depth of the rear cover 21 and thus the angle sensor 33 is large. The detection sensitivity of is high. Also, the pivot point 20
Since the sensitivity becomes dull as the position becomes lower (the L value is smaller), it is assumed that the control device 30 controls the plowing depth based only on the fluctuation value of the rotation angle of the rear cover 21. Due to the height of the pivot point, the detection sensitivity for controlling the plowing depth to be constant is different, and stable control cannot be realized.

Therefore, in the present invention, the detection sensitivity is corrected so that the detection sensitivity of the rear cover 21 and the angle sensor 33 becomes substantially constant even when the rotating position of the tilling cover body 13 changes. Next, with reference to the flowchart of FIG. 5, a mode of control of detection sensitivity correction by the control device 30 as the tilling depth detection sensitivity adjusting device in the rotary tiller will be described.

Following the start, the load value W is detected by the load sensor 31 (step S1). Then, it is determined whether or not the load W is within a predetermined range with respect to the set value (step S2). Here, X1 is the upper limit value of the set load, and X2 is the lower limit value. When the detected load W is within the predetermined range (step S2, yes), the turning hydraulic cylinder 2
2 does not work. When the detected load W is less than the lower limit value X2, the turning hydraulic cylinder 22 is contracted, the plowing cover body 13 is turned forward, and L is increased (step S3). When the cultivating cover body 13 is rotated forward, the gap (space) between the rear part of the lower surface of the cultivating cover body 13 and the lower surface of the rear cover 21 and the rotation locus of the cultivating claw body 17 is narrowed, and the cultivated soil is easily collected. , The towing load increases.

When the detected load W is larger than the upper limit value X1, the turning hydraulic cylinder 22 is extended, the plowing cover 13 is turned backward, and L is decreased (step S).
4). When the cultivating cover body 13 is rotated rearward, a gap (space) between the rear portion of the lower surface of the cultivating cover body 13 and the lower surface of the rear cover 21 and the rotation locus of the cultivating pawl body 17 is widened, and the accumulated soil easily drops. Therefore, the towing load is also reduced.

Next, in step S5, it is determined to which section the L belongs. For example, the section is divided into five sections A, B, C, D, and E. Each section A
The comparison between ~ E and the size of L is shown in Fig. 6. Then, a predetermined sensitivity correction is executed according to the determined section (steps S6 to S10). In each section, the reference value of the rotation angle of the rear cover 21 with respect to the vertical line, in other words, the operation reference value θ by the angle sensor 33.
1, θ2, θ3, θ4, θ5 and the width value of each dead zone (± α
1), (± α2), (± α3), (± α4), (± α
5) Set to change and. These α1 to α5 are sensitivity correction values. It should be noted that in θ, the reference value becomes larger as the subscript goes from 1 to 5, and in α, the reference value becomes smaller as the subscript goes from 1 to 5.

Table 1 shows the range of L, the section and the setting formula for the sensitivity correction in the section.

[0025]

[Table 1]

In section A, for example, the angle sensor 3
When the detected value of 3 is within the range of θ1 ± α1, the dead zone in which the lifting hydraulic mechanism 5 is not operated is set, and the detected value is θ1.
When it exceeds + α1 and is large, the hydraulic mechanism 5 for raising and lowering is operated so that the rotary cultivator 2 is in the ascending direction, and when the detected value is smaller than θ1-α1, the rotary cultivator 2 is in the descending direction. The lifting hydraulic mechanism 5 is operated (see FIG. 7).

[0027]

As described above, the sensitivity adjusting device for detecting the plowing depth in the rotary tiller of the present invention is
In a rotary cultivator that is connected to a traveling vehicle equipped with an engine so that it can be adjusted up and down, towed, and driven, the cultivating cover body of the rotary cultivator is rotated around a horizontal cultivating pawl shaft by a drive actuator. In addition to being provided so that the moving position can be adjusted, a rear cover whose lower end can be grounded in a field scene is attached to the rear end of the tilling cover body so as to be vertically rotatable, and the rear cover is provided between the tilling cover body and the rear cover. An angle sensor for detecting the turning angle is provided, and a control device is provided to control so as to keep the tilling depth constant by the detection value of the angle sensor, and according to the detection value of the load sensor for detecting the traction load. Then, while the drive actuator is operated to rotate the tillage cover body in the direction in which the load is reduced, the control device determines the detected value of the angle sensor. Therefore, since the control is performed so as to correct the sensitivity of detecting the plowing depth, the soil that becomes jammed between the plowing cover body and the plowing cover body at the time of plowing work by the rotary tiller is rotated so that the pulling load is increased. The present invention has an effect that the sensitivity of detecting the tilling depth by the rear cover and the angle sensor can be kept substantially constant when the tilling depth by the rotary tiller is controlled to be constant while preventing the increase of the tilling depth.

[Brief description of drawings]

FIG. 1 is a side view of a tractor and a rotary tiller.

FIG. 2 is a side sectional view of a main part of a rotary cultivator.

FIG. 3 is a longitudinal sectional view of a main part of a rotary cultivator.

FIG. 4 is a functional block diagram of a control system.

FIG. 5 is a flowchart showing a control mode of a plowing depth detection sensitivity correction.

FIG. 6 is a diagram showing a relationship between a range of a height position L of a tilling cover body and a section.

FIG. 7 is a diagram showing a relationship between tillage depth detection and lifting operation control of a rotary tiller.

[Explanation of symbols]

 1 tractor 2 rotary tiller 3 engine 4 link mechanism 5 lifting hydraulic mechanism 9 tilling claw shaft 13 tilling cover body 21 rear cover 22 turning hydraulic cylinder 30 control device 31 load sensor 32 cover position detector 33 angle sensor 34 tilling depth setting Vessel 35 electronic governor

Claims (1)

[Claims] 1. A rotary cultivator which is connected to a traveling vehicle equipped with an engine so as to be adjustable in vertical movement, towed, and driven, and a cultivating cover body of the rotary cultivator is horizontally cultivated by a drive actuator. The rear cover is provided at the rear end of this tillage cover body so that the lower end can be grounded in the field, and is vertically rotatable so that the rotation position can be adjusted around the claw shaft. Is provided with an angle sensor for detecting the rotation angle of the rear cover, and a control device for controlling the cultivation depth to be kept constant by the detection value of the angle sensor, and a load sensor for detecting a towing load. Depending on the detected value of
The drive actuator is operated to rotate the tilling cover body in a direction in which the load is reduced, while the control device controls to correct the tilling depth detection sensitivity based on the detection value of the angle sensor. For detecting sensitivity of tilling depth in rotary tiller.