JPH0260508A - Control device of tilling depth in tractor - Google Patents

Abstract

PURPOSE:To improve accuracy of control of tilling depth in the vicinity of difference in level on the surface of the earth by controlling tilling depth of ground working machine on both detected values of a ground height sensor and an angle sensor and delaying operation of a lift arm until traveling of distance between the ground height sensor and the ground working machine is measured by a traveling distance. CONSTITUTION:An angle sensor 6 such as potentiometer is attached to a revolution shaft of a lift arm 4 for raising and dropping a rotary working machine 10 set at the rear of a tractor 1 to set height of the working machine 10. A ground height sensor 18 such as ultrasonic sensor is laid at a part behind an axle shaft of rear wheels, detected values of both the sensors are inputted to CPU of a control circuit, the angle of the lift arm 4 is compensated by CPU and variability of tilling depth during dropping of the rear wheels is prevented. After traveling of distance corresponding to an interval between the ground height sensor 18 and the working machine 10 is measured by a traveling distance sensor 19, an return order is outputted to the lift arm 4 by CPU. Consequently, variability of tilling depth in difference in level resulting from distance between the ground height sensor 18 and the ground working machine 10 can be prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a plowing depth control device for a tractor, and in particular, it relates to a plowing depth control device for a tractor that changes the plowing depth near a step. This relates to a control device.

[Prior Art] A conventional plowing depth control device for this type of tractor is provided with a CPU that controls a lift arm for raising and lowering a ground work machine. Further, for example, an angle sensor is provided between the rear cover and the top cover of the rotary to be connected to the tractor, and is connected to the CPU, and the lift arm is raised and lowered based on the plowing depth value detected from the ground contact angle of the rear cover. It controlled the υF depth of the rotary.

Further, an ultrasonic sensor is provided at the lower part of the tractor, and the subsidence of the rear wheels is detected based on the ground clearance measured by the ultrasonic sensor,
A system that corrects the plowing depth of ground work equipment has also been proposed.

[Problems to be Solved by the Invention] The tillage depth control device in the conventional tractor described above does not raise or lower the lift arm due to the difference in the measuring point of the sensor and the tilling point of the ground work machine. When controlling the plowing depth using the method, a deviation from the actual topography occurred and the plowing depth could not be maintained constant.

Therefore, a technical problem arises that must be solved in order to improve the accuracy of plowing depth control near the level difference, and the present invention aims to solve this problem.

[Means for Solving the Problems] This invention was proposed to achieve the above object, and includes a ground height sensor provided behind the rear wheel axle of a tractor, and a An angle sensor is provided on the lift arm, and the CPU of the control circuit controls the plowing depth of the ground work machine based on the detection values of both sensors.A travel distance sensor is also provided, and the detection value of the ground height sensor indicates whether the ground height sensor has passed the step. control that delays the operation of the lift arm until the travel distance sensor measures the distance traveled between the ground height sensor and the ground work equipment when the fluctuation value returns to the reference value due to time etc. It is an object of the present invention to provide a plowing depth control device for a tractor, characterized in that a CPU is provided with a section.

[Function] According to the present invention, an angle sensor such as a potentiometer is provided on the rotation shaft of a lift arm for raising and lowering the working machine provided at the rear of the tractor, so that the height of the working machine can be set. In addition, a ground clearance sensor such as an ultrasonic sensor is provided behind the rear wheel axle, and the detection values of both sensors are input to the CPU of the control circuit, and the CPU corrects the angle of the lift arm to detect, for example, if the rear wheel is sinking. This prevents changes in plowing depth due to time, etc. A travel distance sensor is provided, and when the detected value of the ground height sensor returns to the reference value from the fluctuation value, the CPU does not immediately output angle correction to the lift arm. That is, after the travel distance sensor measures the distance traveled corresponding to the distance between the ground height sensor and the ground work machine, the CPU outputs a return command to the lift arm, so that the above-mentioned ground height sensor and the ground work machine It is possible to prevent variations in plowing depth due to differences in level etc. due to the distance from the ground.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the accompanying drawings. For convenience of explanation, conventionally known techniques will also be explained at the same time. In FIG. 1, (1) is a tractor. A lift arm (4) (4) for raising and lowering the work equipment is fixedly installed at the rear of the chassis (2) of the tractor (1) or at the top of the transmission case (3) and is rotated by a hydraulic mechanism (not shown). It is pivoted for free movement. A potentiometer (6) is installed on the rotation shaft (5) of the lift arm (4) (4) so that the angle of the lift arm (/I) (4) with respect to the tractor (1) can be obtained as an electrical signal. It is.

Further, a top link bracket (7) is provided above the rear end of the rear transmission case (3), and a lower link hitch (7) is provided at the rear side of the rear axle housing (8) extending on both left and right sides. 9) (9) is configured to connect working machines. In FIG. 1, the rotor station bar 10) pivots its top link θ1) and left and right lower links OJO, 5 at predetermined positions to form a three-point linkage mechanism (l), and the left and right lower links ( +,!l(+2
A rotary 00) is movable up and down via a lift rod (1) (X) between the middle part of the lift arm (4) and the rope part of the lift arm (4) (4).

Power is transmitted from the PTO output shaft (1) protruding rearward from the rear center of the rear transmission case (3) to drive the rotary claws (10) to perform plowing work.

On the other hand, an ultrasonic sensor (4) for measuring the ground-L height is provided inside the PTO output shaft cover (r7) that covers above the PTO output shaft (1) and on both left and right sides.

In addition, a mileage sensor (a seagull) is fixedly installed on the side of the chassis (2).The mileage sensor (a seagull in this embodiment)
The ultrasonic sensor measures the travel distance equal to the distance (L) between the peak and the rotary claw (1G rotation axis (A)) from the ground speed and time, but it should not be limited to this. , other methods such as reading the distance traveled from the number of rotations of the wheels may also be used.

On the other hand, the operation of the tillage depth control device configured as described above is controlled by the second
This will be explained according to FIGS. 6 to 6. The figure shows the rear wheel (21) of a tractor (1) and the rotor 1 (10) connected to the tractor (1) during plowing work. Also, (G
) is the ground surface, the plowing depth (d) is set in Fig. 2 (^), and the ground height detected by the ultrasonic sensor of the tiger and lid (1) during the progress is (hl). Then, as shown in Figure 3, the ground height detection value (hl) and the angle of the lift arm (4) (
111) is input to the CPU @ and displays the numerical data of plowing depth (d).
It is held as evening.

Here, as shown in FIG. 2 (b), when the tractor (1) passes a step and the rear wheels (21) fall, the detection value of the ultrasonic sensor (day) becomes (h2). In this case, the CPU (to) determines the required angle (α2) of the lift arm (4).
) is calculated and a rising command is output, and the plowing depth (d) of the rotary (10) is held constant. Then, as shown in Fig. 4, as the tractor (1) moves further, the ultrasonic sensor (
The detected value for the day returns to (hl). At this time, CPU@
is the lift arm (4) until the distance sensor (n) measures the distance (1,) from the return point (P).
), and the plowing depth (d) does not change. As shown in FIG. 5, after the tractor (1) has advanced from the return point (P) for an interval (I,),
) outputs a command to the lift arm (/I) to return to the reference angle (ffl), and the lift arm (4) descends to maintain the plowing depth (d).

As a precaution, the operation of the tractor (+) without the travel distance sensor (the distance (L) correction means) will be explained according to FIG. 6.Proceeding from the state shown in FIG. 2 (Il), Ultrasonic sensor (lE6 ground) 1 high detection value or (h2) to (
hl), the CPU (2) changes the detected value (I
Since the required angle (al) of the lift arm (4) is calculated from ll) and a descending command is immediately output, the rotor 1
0 is deeper than the specified plowing depth (d), and this point (0)
The plowing depth becomes deeper between (1°) and the plowing depth becomes uneven.

Note that this invention can be modified in various ways without departing from the spirit of the invention, and it goes without saying that this invention extends to such modifications.

[Effects of the Invention] As detailed in Section 2 - Examples, this invention provides an angle sensor on the lift arm of a tractor, a ground height sensor on the rear of the vehicle body, and detects the detected value of the second sensor. The CPU of the control circuit performs calculations and outputs commands to raise and lower the lift arm to control the plowing depth of the ground work machine. Then, by providing a travel distance sensor, for example, when the detected value of the ground height sensor changes from the reference value after passing through a step and returns to the reference value, the CPU issues a correction command for the lift arm.
It is configured so that the output is not output immediately, but after the distance between the ground-height sensor and the ground work equipment has traveled.

Therefore, variations in plowing depth caused by the distance when passing through a step can be eliminated, making it possible to control plowing depth with extremely high precision, contributing to improved work efficiency.

[Brief explanation of the drawing]

Figures 1 to 5 show one embodiment of the present invention, in which Figure 1 is a side view of a tractor with a rotary connected to it, Figures 2 (person) and (ll) are illustrations of plowing depth control, and FIG. 3 is an explanatory diagram of the control circuit, FIGS. 4 and 5 are explanatory diagrams of plowing depth control, and FIG. 6 is an explanatory diagram of plowing depth control of a tractor without a travel distance sensor. (1)・・・・・Tractor (4)・・・・−・
Lift arm (6)...Potentiometer Qo)
...Rotary (16) ...Rotary claw
(day・・・・−・Ultrasonic sensor (0)・・・・
Mileage sensor (21)...Rear wheel (A)...
...CPU

Claims (1)

[Claims] A ground clearance sensor is installed behind the rear axle of the tractor.
In addition, an angle sensor is provided on the lift arm for raising and lowering the work machine, and the CPU of the control circuit controls the plowing depth of the ground work machine based on the detection values of both sensors. When the detected value of the sensor returns to the reference value from a fluctuating value such as when passing over a step, the lift arm is operated until the travel distance sensor measures the distance traveled between the ground height sensor and the ground work equipment. 1. A tillage depth control device for a tractor, characterized in that a CPU is provided with a control section configured to delay the plowing depth.