JPH04360604A - Mechanism for controlling plowing depth of tractor - Google Patents

Abstract

PURPOSE:To control the plowing depth with a good accuracy by installing a plowing depth controlling mechanism on a signal from ultrasonic plowing depth sensors arranged at specific places and a left and right tilt angle controlling mechanism side by side. CONSTITUTION:A left and right tilt angle controlling mechanism on a signal from a tilt detecting sensor 1 arranged at nearly the central part on the top surface of a rear cover in a rotary tiller and a plowing depth controlling mechanism on a signal from ultrasonic plowing depth sensors 5 are installed side by side. The ultrasonic plowing depth sensors are arranged at the central positions of left and right tilt rotation of the working machine or positions [the sensors (5a) and (5b) for parts of uncultivated land and/or the sensors (5c) and (5d) for parts of already cultivated land] on both sides with the central positions of left and right tilt rotation placed therebetween. Thereby, an error is readily prevented from occurring or corrected.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plowing depth control device for a working machine attached to a tractor.

0002

[Prior Art] Tillage depth control, which maintains and controls the tillage depth to a set tillage depth when tilling with a rotary tillage device attached to an agricultural work vehicle such as a tractor, has been known for some time. There is. However, in the past, plowing depth sensors have controlled the plowing depth by detecting the vertical movement angle of the rear cover or leveling plate, treating this angle as the plowing depth. However, in the conventional plowing depth control mechanism that detects plowing depth using the rear cover, the pressing force of the rear cover against the soil surface becomes large, and unless the leveling pressure is increased to a certain extent, it is not possible to improve the plowing depth control accuracy. There was a problem that it was not possible.

[0003] In order to solve the above-mentioned problems,
A method of controlling plowing depth using an ultrasonic plowing depth sensor is known, such as the technique described in Japanese Patent No. 167004. However, due to the nature of the ultrasonic plowing depth sensor, this conventional technology can only obtain information on the height of the soil surface within a narrow range, resulting in the problem that the tilling device moves up and down unnecessarily, making it impossible to obtain a constant plowing depth. It was.

0004

[Problems to be Solved by the Invention] In order to solve the above-mentioned problems, the present invention solves the problem that, when an integral element such as a moving average of an ultrasonic plowing depth sensor is used, hunting reduction and waving phenomena remain on the finished surface. A constant plowing depth cannot be obtained. There is also a method of shortening the time portion of the integral element, but it is nearly impossible to determine the element that satisfies various field or work conditions. Furthermore, in the case of a field with severe unevenness, sensitively raising and lowering the elevation control means of the working machine does not necessarily yield good results in terms of sensitivity and control. In order to solve the above-mentioned problems, the present invention processes and uses detected values obtained by a means for obtaining height information from a non-contact soil surface, such as an ultrasonic plowing depth sensor.

[0005]

[Means for Solving the Problems] The problems to be solved by the present invention are as described above, and next, the means for solving the problems will be explained. That is, an inclination angle control mechanism that controls the horizontal inclination angle of a working machine attached to a tractor and an ultrasonic plowing depth sensor that detects one or both of the heights of uncultivated land and cultivated land;
In a control mechanism in which a plowing depth control mechanism based on a signal from the ultrasonic plowing depth sensor is placed side by side, at two locations on either side of the center position of the left-right tilt rotation of the work implement, or on both sides of the left-right tilt rotation center position,
This is equipped with an ultrasonic plowing depth sensor. Further, the plowing depth value detected by the ultrasonic plowing depth sensor is corrected based on the inclination angle of the longitudinal inclination of the tractor, and a signal is sent to the plowing depth control mechanism.

[0006] Furthermore, the detected value of the ultrasonic plowing depth sensor is smoothed using a calculation method such as a moving average or integration, and the smoothed value is compared with a set plowing depth value, and the values are set in advance at the upper and lower positions of the set plowing depth value. A range setting value is provided, and when the position is outside the range setting value, control is performed using the detected value of the ultrasonic plowing depth sensor as is. In addition, ultrasonic plowing depth sensors can be attached or detached or multiple pieces can be installed, and the detected value can be selected between only the height of uncultivated land, the calculated value of the height of uncultivated land and cultivated land, and the case of only the height of cultivated land. This is what I did.

[0007]

[Operation] Next, the operation of the present invention will be explained. First, a detected value of the ultrasonic plowing depth sensor, a moving average value of the detected value, and an added value of the detected value and moving average value are calculated. Then, when the added value exceeds the dead zone, the working machine lifting device is controlled to reach the plowing depth set value. Further, a range set value is provided outside the dead zone, and when the raw data detected by the ultrasonic plowing depth sensor exceeds the range set value, the raw data is used to control the tilling depth set value. In addition, a plurality of ultrasonic plowing depth sensors can be installed before and after the rotary tillage device, or the ultrasonic plowing depth sensors can be attached and detached to calculate only the height of uncultivated land, the calculated value of the height of uncultivated land and cultivated land, or the calculated value of the height of uncultivated land and cultivated land. It is possible to control the height of cultivated land only. Furthermore, when the tractor travels on an inclination value, the machine body inclines back and forth, so the detection value of the ultrasonic plowing depth sensor 5 differs depending on the inclination. Therefore, the error due to the inclination is corrected. be.

[0008]

[Example] Next, an example of the present invention will be described. FIG. 1 is a side view of a rotary tiller equipped with a tillage depth control mechanism for a tractor according to the present invention, and FIG. 2 is a plan view thereof. A rear axle housing 22 protrudes left and right from a transmission case 21 at the rear of the tractor, and an axle 23 is supported by the rear axle housing 22. The front ends of the lower links 6L and 6R are pivotally supported by the mission case 21, and the rear ends are pivotally supported by a rotary tiller. A hydraulic system is mounted on the upper part of the mission case 21, and a lift arm 8 is provided to protrude rearward from the hydraulic system. Lift arms 8L/8R and lower links 6L/6R
Lift links 24L and 24R are interposed between the
A tilt control cylinder 7 is interposed in the right lift link 24L.

The inclination control of the working machine by the expansion and contraction of the inclination control cylinder 7 is performed by the inclination detection sensor 1 disposed approximately in the center of the top surface of the tilling cover of the rotary tiller. Furthermore, ultrasonic plowing depth sensors 5a and 5b of the present invention are arranged in the lower links 6L and 6R, and emit ultrasonic waves toward the uncultivated land below. In addition, support rods 2L and 2R are protruded to the rear of the rotary tilling device, and the support rods 2L and 2R are
Rear ultrasonic plowing depth sensors 5c and 5d are arranged at the rear. Further, in this embodiment, the rotation angle of the rear cover 17 of the rotary tillage device is used as a tillage depth sensor, and a signal is sent to the harness 1.
8, and the ultrasonic plowing depth sensor 5 substitutes the average value E as a correction value to the detected value to obtain the output value F and control it. The output value F may be obtained directly from the average value E of the depth sensor 5 and controlled.

In FIG. 3, the inclination detection sensor 1, ultrasonic plowing depth sensors 5a and 5b, and ultrasonic plowing depth sensors 5c and 5 are shown.
The mounting position of d is disclosed. In this way, if the work equipment is equipped with a left/right inclination control device, an error will occur in the value of the ultrasonic plowing depth sensor as the work equipment inclines. They are provided on both sides of the center of the left and right lower links 6L and 6R, which is the center of left and right tilting of the machine. In addition, ultrasonic plowing depth sensors 5a and 5b are provided on both sides of the uncultivated area, and ultrasonic plowing depth sensors 5c and 5d are provided on both sides of the cultivated area. Ultrasonic plowing depth sensors 5a and 5b and ultrasonic plowing depth sensors 5c and 5 so that ultrasonic waves can be emitted toward uncultivated land.
d are each placed at a position away from the rotary tiller so that ultrasonic waves can be emitted toward the cultivated land. FIG. 4 shows the dimensional relationship when the value detected by the ultrasonic plowing depth sensor 5 is corrected to make it a more accurate value when the tractor is tilted back and forth due to the slope of the field. That is, L1 is the distance between the front rotational fulcrum of the lower link 6 and the ultrasonic plowing depth sensor 5, and the horizontal distance between L2 and the front rotational fulcrum of the lower link 6 and the tip of the tilling claw of the rotary tiller. The distance L3 is the vertical distance from the pivot point at the tip of the lower link to the tip of the tiller claw.

In FIG. 5, when a plurality of ultrasonic plowing depth sensors 5a, 5b, 5c, and 5d are attached, it is possible to select which ultrasonic plowing depth sensor to use for control. It is a block diagram showing a mechanism. Using a rotary switch or the like, it is possible to select and control five types of sensors: F, R, FF, FR, and RR. In the case of F, only one signal among the ultrasonic plowing depth sensors 5a and 5b is used for control, and in the case of R, one signal among the ultrasonic plowing depth sensors 5c and 5d is used for control. , FF uses the signals of the ultrasonic plowing depth sensors 5a and 5b for control, FR uses the signals of each of the front and rear ultrasonic plowing depth sensors 5, and RR uses the signals of the ultrasonic plowing depth sensors 5c and 5d. The signals are used for control. By properly using the signals from each ultrasonic plowing depth sensor 5, field conditions and use of wet fields, dry fields, etc. can be determined.

[0012] In some cases, the signal from the ultrasonic plowing depth sensor 5 is used as raw data.
Further, the signal is applied to the integrator 12 to integrate or obtain a moving average to obtain smoothed data, or the smoothed integral value D and raw data C are added to be used for control. Control signals for the ascending electromagnetic control valve 9, the descending electromagnetic control valve 10, various display devices 11, etc. are transmitted via the main controller.

FIG. 6 shows an electronic circuit diagram of the tillage depth control mechanism of the tractor of the present invention. The detected value of the ultrasonic plowing depth sensor 5 is converted into an integral value D by an integrator 12a, and the raw data C is added to the integral value D by an adder 15, and the result is sent to the controller. Also, only the raw data C is sent to the controller. Also, tillage depth setting device 13
A set plowing depth value K is set, and above and below the set plowing depth value K, dead zones Y and Y and zone set values Z and Z are set. 12b and 12c are integrators for dead zones Y and Y and range setting values Z and Z. The dead zone Y/Y and the range setting values Z/Z are changed at the same time as the setting of the set plowing depth K is changed.

FIG. 7 illustrates how the raw data C, the integral value D, and the added value change with respect to the set plowing depth value K, the dead zone Y, Y, and the zone setting value Z, Z. It is something. When the raw data C exceeds the range setting value Z.Z, the ascending electromagnetic control valve 9 and the descending electromagnetic control valve 10 are switched. When the integral value D exceeds the dead zone Y.Y, switching between the ascending electromagnetic control valve 9 and the descending electromagnetic control valve 10 is performed.

FIG. 8 shows an overall state transition diagram of the tillage depth control mechanism of the tractor according to the present invention. First, when control starts, initial settings are performed, and then each constant is set. Next, raw data C from the ultrasonic plowing depth sensor 5 is read, and then an integral value D is obtained from the integrator 12. Then, according to the flowchart shown in FIG. 9, the tilt caused by the tilt control is corrected. Next, a selection is made as to which of the ultrasonic plowing depth sensors 5 to use. Next, the average value of the raw data C from each ultrasonic plowing depth sensor 5 is obtained, and the average value is integrated. Also, the average value of the integral values D is calculated. Next, with the integral value D at the center, dead zones Y and Y and range setting values Z and Z are provided above and below. Next, check which zone the raw data C is in. Then, the method of calculating the average value E of the raw data C and the integral value D is changed for each zone. At this time, the time spent in each zone is also measured.

[0016] If the zone has been in the zone for a set time T or more, the zone is shifted to a zone closer to the integral value D than the zone. Forcibly put MT time in the migrated zone. Then, the average value E is corrected to the output value F of the rear cover sensor. The output value F is outputted from the controller to the ascending electromagnetic control valve 9 and the descending electromagnetic control valve 10.

FIG. 9 shows correction values when the body of the tractor tilts back and forth due to the slope of the field. First, at the start of control, initial settings are made, and then each L
Read constants 1, L2, and L3. Then L=L2-L1
Calculate. Next, the value of the tilt detection sensor 1 is read. Next, convert the output value A of the tilt detection sensor 1 into the value of Sin,
Obtain raw data C, and obtain a correction value for the average value E from the above values. The average value E differs depending on the forward and backward tilts. A correction value for the output value F is obtained from the forward and backward tilt values and is sent to the controller. The controller controls the rising solenoid control valve 9.
and controls the lowering solenoid control valve 10.

FIG. 10 shows a flowchart that changes depending on which of the ultrasonic plowing depth sensors 5a and 5b and the ultrasonic plowing depth sensors 5c and 5d is selected. First, initial settings are made at the start of control, and then range setting values Z and Z are set according to the control state. In addition, the correction values k and kk due to the longitudinal inclination, the set time T, the forced time MT, etc. are read. Next, set the values in the flowchart to F, R, FF, FR, R of the position setting device.
Depending on the difference in R, different flowcharts are selected. Then, the average value E of the ultrasonic plowing depth sensor 5 selected according to each flowchart is substituted into the formula of the plowing depth control mechanism to obtain the output value F, and the controller controls the ascending electromagnetic control valve 9 and the descending electromagnetic control valve. Control valve 10 is controlled.

FIGS. 11 to 15 each explain the SUB routine in the flowchart of FIG. 10. Each SUB routine includes the reading SUB routine shown in FIGS. 16 to 20 and the zone determination S shown in FIG.
It includes the UB routine and the calculation SUB routine in FIG.

Furthermore, in the calculation SUB routine of FIG. 22,
The SUB routines of operations 1 to 4 in FIGS. 23 to 26 are included. Also, SU of operations 1 to 4 in FIGS. 23 to 26
The B routine includes the SUB routines of time checks 1 to 4 shown in FIGS. 27 to 30. First, Figure 11
In the SUB routine shown in FIG. 15, data is first read, then a zone is determined, and then calculations are performed and control is performed. In the reading SUB routine from FIG. 16 to FIG. 20, the raw data C of the ultrasonic plowing depth sensor 5 is read, then the correction coefficient k of the longitudinal inclination is determined, and the raw data C is integrated to obtain the integral value D. It is read.

In the zone determination SUB routine shown in FIG. 21, the zone setting value Z.Z is calculated by adding the integral value D. In FIG. 22, the operation S
A UB routine is disclosed in which an integral value D is subtracted from raw data C and this value is calculated in relation to a range setting value Z.Z. In addition, in the calculations 1 to 4 SUB routines in FIGS. 23 to 26, constants a, b, c, and d determined by the rotary tiller are substituted, and the average value E is calculated from the raw data C and integral value D of the constants. . Furthermore, in the time check SUB routines shown in FIGS. 27 to 30, flowcharts are configured to check the time in each zone.

[0022]

[Effects of the Invention] Since the present invention is constructed as described above, the following effects are achieved. That is, as in claim 1,
A tilt angle control mechanism that controls the left and right tilt angle of the work equipment attached to the tractor, and an ultrasonic plowing depth sensor that detects either or both of the heights of uncultivated land and cultivated land; In the control mechanism, which is equipped with a plowing depth control mechanism using signals from Even when the machine is tilted left or right, the ultrasonic plowing depth sensor 5 can always accurately detect the height above the ground.

Furthermore, according to the second aspect of the present invention, the plowing depth value detected by the ultrasonic plowing depth sensor is corrected based on the inclination angle of the longitudinal inclination of the tractor, and a signal is sent to the plowing depth control mechanism. This makes it possible to eliminate the error that occurs in the detected value of the ultrasonic plowing depth sensor 5 when the plow tilts back and forth due to the slope of the field.

[0024] Also, since the structure is configured as in claim 3, the detected value of the ultrasonic plowing depth sensor is smoothed using a calculation method such as moving average or integration, and is compared and controlled with the plowing depth setting value, and the plowing depth setting value is controlled. Set preset range setting values at the upper and lower positions of the value,
When the position is outside the range setting value, the configuration is such that control is performed using the detected value of the ultrasonic plowing depth sensor as is, so that the following problems of the prior art can be solved. In other words, because the detection range of the ultrasonic plowing depth sensor is narrow, it is only possible to measure the height within a certain narrow range, and if raw data C is used for control, the work machine will move up and down unnecessarily. A certain plowing depth could not be achieved. In order to solve this problem, the present invention uses an integral element such as a moving average to eliminate hunting and avoid the occurrence of waviness in the finished product.

In addition, as in claim 4, the ultrasonic plowing depth sensor is detachably installed or a plurality of ultrasonic plowing depth sensors are arranged, and only the height of uncultivated land, the calculated value of the height of uncultivated land and cultivated land, and the calculated value of only the height of cultivated land can be measured. By making the cases and detection values freely selectable, depending on the type of work, the ultrasonic plowing depth sensors 5a and 5b for uncultivated land, the ultrasonic plowing depth sensors 5c and 5d for cultivated land, or both. It became possible to select one of them, and control according to the situation became possible.

[Brief explanation of drawings]

FIG. 1 is a side view of a tractor according to the present invention with a plowing depth control mechanism attached to the rear of the tractor.

FIG. 2 is a plan view as well.

FIG. 3 is a plan view showing the arrangement of a plurality of ultrasonic plowing depth sensors 5 and a tilt sensor 4 in a rotary tiller.

FIG. 4 is a side view of the rotary tiller showing a state in which the inclination angle based on longitudinal inclination control of the tractor is corrected with respect to the detection device of the ultrasonic plowing depth sensor.

FIG. 5 is a block diagram of the plowing depth control mechanism of the tractor of the present invention.

FIG. 6 is an electronic circuit diagram of a plowing depth control mechanism of a tractor according to the present invention.

FIG. 7 is a diagram showing changes in plowing depth, detected values, and calculated values in a control state.

FIG. 8 is an overall flowchart of the tillage depth control mechanism of the tractor.

FIG. 9 is a flowchart for correcting the detected value of the ultrasonic plowing depth sensor 5 by the inclination angle of the longitudinal inclination of the tractor.

FIG. 10 is a main flowchart of data processing of the tillage depth control mechanism of the tractor.

FIG. 11 is a drawing showing the F-SUB routine in the flowchart of FIG. 10;

FIG. 12 is a drawing showing the R-SUB routine in the flowchart of FIG. 10;

FIG. 13 is a diagram showing the FF-SUB routine in the flowchart of FIG. 10;

FIG. 14 is a drawing showing the FR-SUB routine in the flowchart of FIG. 10;

FIG. 15 is a diagram showing the RR-SUB routine in the flowchart of FIG. 10;

[Figure 16] F reading-S in the flowchart of Figure 11
A drawing showing a UB routine.

[Figure 17] R reading-S in the flowchart of Figure 12
A drawing showing a UB routine.

FIG. 18 is a drawing showing the FF reading-SUB routine in the flowchart of FIG. 13;

FIG. 19 is a drawing showing the FR reading-SUB routine in the flowchart of FIG. 14;

FIG. 20 is a diagram showing the RR read-SUB routine in the flowchart of FIG. 15;

FIG. 21 is a drawing showing the zone determination-SUB routine in the flowcharts of FIGS. 11 to 15;

FIG. 22 is a drawing showing an operation-SUB routine in the flowcharts of FIGS. 11 to 15;

[Figure 23] Operation 1-SU in the flowchart of Figure 22
Drawing showing B routine.

[Figure 24] Operation 2-SU in the flowchart of Figure 22
Drawing showing B routine.

[Figure 25] Operation 3-SU in the flowchart of Figure 22
Drawing showing B routine.

[Figure 26] Operation 4-SU in the flowchart of Figure 22
Drawing showing B routine.

FIG. 27 is a diagram of the time check 1-SUB routine in the flowchart of FIG. 23;

FIG. 28 is a diagram of the time check 2-SUB routine in the flowchart of FIG. 24;

FIG. 29 is a diagram of the time check 3-SUB routine in the flowchart of FIG. 25;

FIG. 30 is a diagram of the time check 4-SUB routine in the flowchart of FIG. 26;

[Explanation of symbols]

1 Inclination detection sensor 5a, 5b Ultrasonic plowing depth sensor 5c, 5d for uncultivated land
Ultrasonic plowing depth sensor for cultivated land 6 Lower link 7 Inclination control cylinder R Rotary tilling device C Raw data of ultrasonic plowing depth sensor D Integral value Y Dead zone Z Zone setting value

Claims (4)

[Claims] 1. An inclination angle control mechanism that controls the horizontal inclination angle of a work implement attached to a tractor, and an ultrasonic plowing depth sensor that detects either or both of the heights of uncultivated land and cultivated land; In a control mechanism that is equipped with a plowing depth control mechanism that uses signals from a sonic plowing depth sensor, ultrasonic plowing depth sensors are installed at the center position of the horizontal tilting rotation of the work implement, or at two locations across the horizontal tilting rotation center position. A tractor plowing depth control mechanism characterized by the following arrangement. 2. The plowing depth control mechanism for a tractor according to claim 1, wherein the plowing depth value detected by the ultrasonic plowing depth sensor is corrected based on the inclination angle of the longitudinal inclination of the tractor, and a signal is sent to the plowing depth control mechanism. A plowing depth control mechanism for a tractor, characterized in that it is configured as follows. 3. The plowing depth control mechanism for a tractor according to claims 1 and 2, wherein the detected value of the ultrasonic plowing depth sensor is smoothed using a calculation method such as a moving average or integration, and is compared with a set plowing depth value. A preset area setting value is set above and below the tilling depth setting value, and when the area is located outside the area setting value, control is performed using the detected value of the ultrasonic tilling depth sensor. A plowing depth control mechanism for a tractor, characterized by comprising: 4. The plowing depth control mechanism for a tractor according to claim 1, wherein the ultrasonic plowing depth sensor is removably installed or a plurality of ultrasonic plowing depth sensors are arranged, and only the height of the uncultivated land and the calculated value of the height of the uncultivated land and the cultivated land are calculated. , a tillage depth control mechanism for a tractor, characterized in that only the height of cultivated land and the detected value can be freely selected.