JPH0773446B2 - Lifting position control device for work machine in traveling work machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a working depth of a working machine connected to a main body of a traveling working machine such as an agricultural tractor, that is, a ground of a grounding end of the working machine. The present invention relates to a lift position control device for controlling a position with respect to a surface.

(Prior art and its problems) Conventionally, as a method for controlling the working depth of a working machine connected to the main body of a traveling working machine, for example, one disclosed in Japanese Utility Model Publication No. 55-39690 is known. Has been. According to this, a sensor (mechanism 11) for detecting the inclination angle (θ ₁ ) of the working machine body (agricultural tractor A) with respect to the ground surface,
A sensor (mechanism 12) for detecting the mounting inclination angle (θ ₂ ) of the working machine (rotary device B) with respect to the working machine body (agricultural tractor A) is provided, and the working depth of the working machine is calculated based on the outputs of both sensors. It is configured to do.

However, according to such a conventional configuration, since the working depth of the working machine is calculated independently of the reference installation surface of the traveling work machine body, the tilling depth value as the calculation result is relative to the reference installation surface of the traveling work machine body. There is a problem in that it changes depending on the position of ups and downs, making it impossible to accurately control the working depth of the working machine.

(Means for Solving Problems) The present invention has been made to solve the problems of the prior art, and is directed to a working machine for controlling a working machine mounted behind a traveling working machine body so as to be vertically movable. In a lifting position control device, a ground sensor that is provided in front of the working machine and detects a floating position of the traveling work machine body with respect to the ground surface, and an lifting position that detects a lifting position of the working machine with respect to the traveling work machine body. A detection sensor, an inclination sensor that detects an inclination angle of the traveling work machine main body with respect to a reference installation surface in the front-rear direction, and the floating and sinking position detected by the ground sensor based on the output of the inclination sensor with respect to the reference installation surface. Based on the output of the tilt sensor and the first correction means for correcting to the up / down position, the up / down position detected by the up / down position detection sensor is used as the base. Second correction means for correcting the ascending / descending position with respect to the semi-installed surface, and the first and second correction means.
Based on the correction means of the above, the operating means for calculating the working depth position of the working machine from the ground surface, and the position of the working machine to the predetermined position by the output of the calculating means, It is an object of the present invention to provide a lifting control device that can calculate the true working depth value of a working machine regardless of the positional relationship of the working machine body to the installation surface and can always perform the working machine's working depth accurately. To do.

(Operation) When the traveling work machine main body floats or sinks from the reference installation surface by a predetermined amount, each output of the ground sensor and the elevation position detection sensor is corrected by the operation of the correction means based on the output of the tilt sensor. Thereby, the accurate working depth value of the working machine can be calculated, and the working depth of the working machine can be accurately maintained at a desired value.

(Embodiment) FIG. 2 and FIG. 3 show an external configuration of an agricultural tractor as a traveling work machine according to the present invention. An elevating mechanism 2 is provided behind the tractor body 1 (on the rear wheel 11 side). The rotary device 3 as a working machine is connected via the. Here, the elevating mechanism 2 is composed of a link mechanism composed of a pair of left and right lower links 2a and 2b and a top link 2t, and the elevating mechanism 2 is driven by a hydraulic cylinder 4 which is a pair of left and right hydraulic cylinders. The lift arms 5a and 5b and the left and right lift rods 6a and 6b are connected to the lower links 2a and 2b, respectively. Further, behind the tractor main body 1, between the tractor main body 1 and the rotary device 3 as a working machine, the vertical movement of the grounding end of the rear wheel 11 is followed, and at the time of work, the ground surface is constantly contacted and rolled. A moving front tail wheel 7 is provided.

On the other hand, a predetermined portion of the tractor body 1 has the tractor body 1
An inclination sensor 8 for detecting the inclination angle in the front-rear direction with respect to the reference installation surface P ₁ (the ground surface when the tractor body 1 is assumed not to float) is provided, and the elevation mechanism 2 is provided at a predetermined portion of the elevation mechanism 2. An elevation position detection sensor 9 for detecting an elevation amount of the rotary device 3 connected to the tractor body 1 is provided, and a ground portion for detecting a floating position of the tractor body 1 with respect to the ground surface at a predetermined portion of the front tail wheel 7. A sensor 10 is provided.

Here, more specifically, the tilt sensor 8 converts the swing angle of a pendulum that tilts in accordance with the tilt of the tractor body 1 into an electrical signal, and the conversion output is the front-back direction of the tractor body 1. While changing linearly with respect to the inclination angle of, the converted output is usually superposed with low-frequency noise of, for example, about 2 Hz due to disturbance due to so-called pitching of the tractor body 1.

Further, the lift position detection sensor 9 linearly converts the rotation angle of the lift arms 5a and 5b into an electric signal by mounting a potentiometer on the shafts of the lift arms 5a and 5b of the lift mechanism 2, for example. Is.

Further, the ground sensor 10 includes a support arm 7a for the front tail wheel 7 and a rear wheel.
The potentiometer is provided on the bearing at the connection portion with the axle 11 and has an output that linearly changes according to the rotation angle of the support arm 7a.

FIG. 1 schematically shows the overall configuration of the elevator control device. The tilt sensor 8 is provided with a filter 12 for cutting the low frequency noise described above from its output V ₂ and its output. V ₂ ′ is supplied to the subtractor 13 together with the output V _{1 of} the ground sensor 10, and the subtracter 13 performs an operation of subtracting the output V ₂ ′ of the tilt sensor 8 from the output V ₁ of the ground sensor 10 to obtain the rear wheel. The position of the ground end of 11 with respect to the reference installation surface P ₁ is detected. That is, if the output V ₃ of the subtractor 13 is, for example, a positive value, the grounding end of the rear wheel 11 is at a position that is sunk from the reference installation surface P ₁ , and if it is a negative value, the reference installation surface P _{1 is} And the position is zero, it means that it is at the same position as the reference installation surface P ₁ .

Further, the output V ₀ of the ascending / descending position sensor 9 is supplied to the correction circuit 14 together with the output of the tilt sensor 8 (correctly, the output V ₂ ′ of the filter). In the correction circuit 14, the rotation angles of the lift arms 5a and 5b are changed. Each time, a change of the ground contact end position of the rotary 3a with respect to the tilt angle of the tractor body 1 in the front-rear direction is detected. That is,
If the output V ₄ of the correction circuit 14 is a positive value, for example, the grounding end of the rotary 3a is at a predetermined working depth position from the reference installation surface P ₁ regardless of the ups and downs of the tractor body 1, and a negative value. if, in a position which emerged than the reference installation surface P _1, and represents that it is in the reference installation surface P ₁ positions for a zero.

The outputs V ₃ and V ₄ of the subtracter 13 and the correction circuit 14 are supplied to the adder 15, and the ground surface (actual installation surface of the tractor body 1) P is supplied according to the positive and negative output values of the adder 15. The actual position P ₃ of the ground end of the rotary 3a with respect to ₂ is detected. That is, floating and sinking from the reference installation surface P ₁ of the tractor body 1 is considered, the tilling depth position output V ₅ is the ground end of the rotary 3a If a positive value of a predetermined from the ground surface P ₂ of the adder 15 There, if a negative value grounding end of the rotary 3a is in a position emerged from the ground surface P _2, indicating that there on the ground surface P ₂ if zero.

On the other hand, the output V ₆ of the adder 15 is supplied to the working depth display circuit 16,
While the actual working depth amount of the rotary 3a is displayed by the working depth display circuit 16, the output V ₅ of the adder 15 is supplied to the comparison circuit 17 and the working depth setting circuit for setting a desired working depth amount. The output V ₆ of the comparator 18 is compared, and the output V ₇ of the comparison circuit 17 activates the lift drive circuit 19 which is an output circuit for driving the lift mechanism 2. In other words, the output of this comparison circuit 17
V ₇ lift arm 5 when the output V ₆ large becomes than the output V ₅
An ascending drive actuator (specifically, an electromagnetic valve) 23a by outputting a signal for operating the ascending drive circuit 19a of a and 5b
On the contrary, when the output V ₆ becomes smaller than the output V _5, a signal for driving the lowering drive circuit 19b of the lift arms 5a, 5b is output to operate the lowering drive actuator 23b.
Actuators 23a, 2 when output V ₆ equals output V ₅
Stop the drive output of 3b. The lift drive circuit 19 is provided with a sensitivity setting circuit 20, and the drive reaction of the lift mechanism 2 can be adjusted by the output V ₈ of the sensitivity setting circuit 20.

Therefore, the working depth of the rotary 3a can be accurately controlled according to the floating / sinking state of the tractor body 1.

The output V ₀ of the up-and-down position sensor 9 is
The output V ₉ of the upper limit setting circuit 22 is compared, and the output V ₁₀ of the upper limit setting circuit 22 regulates the upper limit of the lifted position of the lift arms 5a and 5b. Further, the output V ₁₀ operates the upper limit position adjustment drive circuit 24. That is, the output V ₁₀ of the comparator 21 outputs a signal for activating the ascending drive circuit 25a of the lift arms 5a, 5b when the output V ₉ is larger than the output V ₀ , thereby activating the ascending drive actuator 23a. On the contrary, when the output V ₀ becomes smaller than the output V _9, a signal for driving the lowering drive circuit 25b of the lift arms 5a and 5b is output to operate the lowering drive actuator 23b and output V ₀
Stops output when is equal to output V ₉ .

The lift drive circuit 19 and the upper limit position adjustment drive circuit 24 operate the changeover switch 26 (contacts 26a sandwiching the neutral contact 26c,
It can be operated selectively by switching 26b).

(Effects of the Invention) As described above, according to the present invention, in the work machine lifting position control device for controlling the work machine mounted on the rear side of the traveling work machine body so as to be able to move up and down, the work machine is provided in front of the work machine. A ground sensor for detecting a floating position of the traveling work machine body with respect to the ground surface, and an elevation position detection sensor for detecting an elevation position of the working machine with respect to the traveling work machine body,
An inclination sensor that detects an inclination angle of the traveling work machine main body with respect to a reference installation surface in the front-rear direction, and based on the output of the inclination sensor, the floating / sink position detected by the ground sensor is corrected to a floating / sink position with respect to the reference installation surface. And a second correcting means for correcting the ascending / descending position detected by the ascending / descending position detecting sensor to an ascending / descending position with respect to the reference installation surface based on the output of the tilt sensor; Based on the second correction means, the working means for calculating the working depth position of the working machine from the ground surface and the configuration for controlling the working machine to a predetermined position by the output of the calculating means are used. Regardless of the positional relationship of the machine body with respect to the ground surface, the true working depth value, which is the working depth position from the ground surface of the working machine, can be calculated, and the position for maintaining the working machine at a predetermined position can be calculated. Always controlled accurately performed, it can contribute to work efficiency improvement of agricultural like. Further, since the sensor of the ascending / descending position control device according to the present invention can be provided with a ground sensor in addition to the conventional ascending / descending position detecting sensor and inclination sensor, a significant increase in cost can be avoided.

[Brief description of drawings]

FIG. 1 is a block diagram showing the overall construction of an embodiment of the present invention, FIGS. 2 and 3 show an agricultural tractor according to the present invention, and FIG. 2 is a side view thereof and FIG. FIG. 3 is a perspective view of the main part thereof. 1 ...... tractor body (mobile work vehicle body), 2 ...... lift mechanism, 3 ...... rotary device (working machine), 8 ...... tilt sensor 9 ...... vertical position sensor, 10 ...... ground sensor, P ₁ ... Standard installation surface.

Claims (1)

[Claims] 1. A lifting / lowering position control device for a working machine, which controls a working machine mounted rearward of the traveling work machine main body so as to be able to move up and down, and is provided in front of the working machine with respect to a ground surface of the traveling work machine main body. A ground sensor for detecting a floating position, an elevation position detection sensor for detecting an elevation position of the working machine with respect to the traveling work machine body, and an inclination sensor for detecting an inclination angle of the traveling work machine body with respect to a reference installation surface in the front-rear direction. And a first correction unit that corrects the floating / sinking position detected by the ground sensor to a floating / sinking position with respect to the reference installation surface based on the output of the tilt sensor, and the ascending / descending position detection based on the output of the tilt sensor. Second correction means for correcting the ascending / descending position detected by the sensor to an ascending / descending position with respect to the reference installation surface, and based on the first and second correcting means. A working unit for computing a working depth position of the working unit from the ground surface, and a position control unit for controlling the working unit to a predetermined position by the output of the computing unit. Lifting position control device.