JPH0227904A - Apparatus for controlling working part of mobile farm working machine - Google Patents

Abstract

PURPOSE:To prevent uncomfortable shock at the stop of a working part by controlling a working part lifting apparatus in such a manner as to smoothly decelerate the lifting motion of the working part. CONSTITUTION:A working part is vertically displaced by a hydraulic actuator energized by a signal transmitted to a lifting or lowering solenoid by the operation of a position lever. The above lifting apparatus is provided with a lift angle detection means to detect the lift angle of the working part and with a real speed calculation means to calculate the real lifting speed of the working part. When the working part reaches a prescribed height determined by the lift angle detection means, the duty ratio of the output signal to the lifting solenoid is gradually decreased to decelerate the lifting motion until the duty ratio reaches a prescribed level, when the lifting speed is maintained at a constant level by a feed-back control based on the real speed calculation means.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a working part control device for a mobile agricultural machine such as a tractor. The present invention relates to a working part control device that controls lifting operation.

(b) Conventional technology In general, a mobile machine, such as a tractor, has a running body supported by front wheels and rear wheels, and a rotary work machine or the like can be freely attached to the rear of the running body based on the operation of a position lever. The rotary work machine is mounted so that it can be raised and lowered, and by operating the position lever to the lowered position and driving the rotary work machine in a state that it is driven into the field, tasks such as tilling and plowing are performed.

In addition, when the above-mentioned tractor raises a rotary working machine or the like from the ground position to the highest position, the rising speed is monotonous, so when the working machine stops due to inertia, an unpleasant shock occurs. In particular, when a rotary and fertilizer seeding machine is attached to perform tilling, sowing, and fertilizing at the same time, seeds in the hopper may spill or damage the seeds due to the position of the center of gravity of the entire machine. This may cause other problems.

(c) Problem to be solved by the invention For this reason, when an operator lifts a rotary or other working machine, it is necessary to slowly operate the position lever, which makes the operation very troublesome and makes the work difficult. It's also inefficient and ends up being a waste.

Therefore, the present invention reduces the speed from a predetermined raised position and controls the speed to a constant speed when the working part is raised.
The object of the present invention is to provide a working unit control device that solves the above-mentioned problems.

(:) Means for Solving the Problems The present invention has been made in view of the above-mentioned circumstances. For example, as shown with reference to FIGS. lowering solenoid (2
2) and (23) to output a signal to the hydraulic actuator (
34), and the working part (11) is raised and lowered.
a lifting angle detecting means (19) for detecting the lifting angle of the working part (11); an actual speed calculating means (24) for calculating the actual lifting speed of the working part (11); From the time when the specified height based on (19) is reached,
a rise deceleration means (44) that gradually reduces the duty ratio of the output signal to the rise solenoid (22) to decelerate the rise speed; The present invention is characterized in that it includes feedback control means (28) for raising the working section (12) at a constant speed based on the speed calculation means (24).

(f) Function Based on the above-mentioned configuration, for example, as shown in FIG.
) is activated and the working part (11) is raised. Further, from the time when the ascending angle of the working part (11) detected by the ascending/descending angle detecting means (19) reaches a predetermined angle, the ascending/descending deceleration means (
44), the duty ratio of the output signal to the hydraulic actuator (34) is gradually reduced and the working part (11
) is decelerated, and from the point at which the duty ratio reaches a preset value, the working part (11) is controlled by the feedback control means (28) to maintain a constant speed and ascends. Therefore, the working part (11) is smoothly stopped at the highest position.

Note that the symbols in parentheses do not limit the configuration in any way.

(F) Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

As shown in FIGS. 2 and 3, the tractor 1 has front wheels 2.
It has a running body 5 supported by rear wheels 3, and a driver's seat 6 is disposed approximately in the center of the traveling body 5. The driver's seat 6 has a steering wheel 7, a position A lever 9 and a seat 10 are respectively installed. Further, at the rear of the traveling body 3, a working part 11 is mounted so as to be able to be raised and lowered via a lift arm 8, a link 14, etc., and a hydraulic cylinder 34 for raising and lowering the working part is installed in the lift arm 8 portion. Furthermore, the working section 11 has a rotary working machine 12 and a fertilizing/seeding machine 13. In addition, in the figure, 15 is a seed tank, and 16 is a fertilizer tank.

On the other hand, the microcomputer 17 installed on the tractor l
(hereinafter referred to as a microcomputer), as shown in FIG.
and a work equipment switching volume 20 are connected, and on the output side, via an output interface 21, there are a lift arm raising solenoid 22 and a lift arm lowering solenoid 23 that operate the lift arm switching pulp.
are connected. Furthermore, the microcomputer 17 includes an actual speed calculating means 24 that calculates the actual vertical speed of the working section 11 by calculating the amount of change in value per unit time of the output signal from the lift arm angle sensor 19; a descending deceleration means 44 that decelerates the actuator 19 by decreasing the duty ratio of the signal output to the lift arm raising solenoid 22 by a fixed ratio from the time when the height reaches a predetermined height based on the lift arm angle sensor 19; Feedback control means 28 is provided for lowering the working part 11 at a constant speed based on the actual speed calculation means 24 from the time when the duty ratio reaches a preset value. Further, based on the lowering operation of the position lever 9, the microcomputer 17 outputs an inching signal so that the duty ratio decreases by a fixed ratio, and controls the working part lifting hydraulic cylinder 34 to adjust the lowering speed of the rotary working machine 12. descending deceleration means 48 that operates so that the speed gradually decreases, and from a predetermined duty ratio position, the feedback control means
8 lowers the working part 11 at a constant low speed based on the actual speed calculating means 24.

Moreover, as shown in FIG. 4, in a predetermined part of the driver's seat 6,
A mode switching volume 26, the working machine switching volume 20, a position adjustment volume 27, and the like are provided.

Next, the operation of this embodiment will be explained using the time chart shown in FIG.

In the figure, the horizontal axis shows the passage of time, the vertical axis (a) shows the position control setting by the position lever 9, and (b) shows the lifting angle of the rotary work machine 12 and the fertilizer seeding machine 13 by the lift arm angle sensor 19. (8) shows a control signal to the lift arm raising solenoid 22, and (d) shows a control signal to the lift arm lowering solenoid 23. When performing tillage and seeding work using the rotary work fi12 and the fertilizing and seeding machine 13, the operator first operates the working machine switching volume 20 to switch to the fertilizing and seeding machine mode. In this state, when the position lever 9 is operated to the highest position, (a) the operating angle of the lever 9 is detected by the position detection sensor 18 and input to the microcomputer 17;

Based on this, the working part 11, that is, the lift arm 8 is angled. (b) Lift arm raising solenoid 22
(c) The working part 11 is quickly raised by turning on the switch continuously. And the angle of lift arm 8. At the point in time (d), as shown in FIG. 5(a), the duty ratio of the control pulse signal is decreased by a fixed ratio every cycle by the ascending deceleration means 44, so that the working part 10 is smoothly moved. Slowed down. Then, from the point when the duty ratio reaches a predetermined ratio, that is, from the part A in the figure, the working part 11
is raised to the highest position at a constant speed by the feedback control means 28, while the actual speed of rise is detected by the actual speed detection means 24, and the duty ratio of the pulse signal is appropriately increased or decreased (feedback control).
, the working part 11 is held at the highest position (f). Therefore, the rotary work machine 12 and the fertilizer seeding machine 13 are raised quickly and slowly and smoothly from near the highest point, so that no unpleasant shock occurs, and the seed tank 1
The seeds inside 5 will not be damaged or spilled.

Furthermore, when the tractor 1 traveling in this state reaches the working position, if the position lever 9 is lowered (g)
The operating position of the lever 9 is detected by the position detection sensor 18, and the descending deceleration means 48 based on this detects the operation position.
An inching signal (h) in which the duty ratio is decreased by a constant ratio from a position close to 100% (as shown enlarged in FIG. 5(b)) is outputted to the lift arm lowering solenoid 23. As a result, the rotary working machine 12 and the fertilizing seeding machine 13 descend from the highest position quickly and at a gradually reduced speed (i). Then, from the time when the pulse signal to the lift arm lifting solenoid 22 reaches the preset duty ratio (j), the rotary work machine 12 is controlled by the feedback control means 28.
While the actual speed of descent is detected based on the actual speed calculation means 24, the duty ratio of the pulse signal (k) (shown enlarged in FIG. 5(c)) is appropriately increased or decreased until it reaches the lowest position at a constant speed. Lowered (feedback control) (β)
, Therefore, when the rotary work machine 12 descends, there is no inflection point where the speed suddenly changes, that is, a fast descending speed when the rotary work machine 12 is at a position significantly above the ground level and a slow descending speed when the position is based on the ground height. There is no switching point to switch to work equipment 12.
It decelerates smoothly, and when it touches down, it makes smooth contact with the field at a constant low speed, and no dashing phenomenon occurs.

Furthermore, when the working machine switching volume 20 shown in FIG. is changed, and therefore, the rising speed control start position is set in a timely manner, so even if the weight of the fertilizing and seeding machine 13 changes, control at the time of rising can be performed appropriately. The value of the position adjustment volume 27 at the time of adjustment in the fertilization and seeding mode is stored, and the value adjustment becomes effective only when the mode is set to fertilization and sowing. However, when the mode is changed to fertilization and seeding mode again, the values stored at the time of adjustment are used as they are, so there is no need to adjust the values each time the mode is changed.
Therefore, it is possible to adjust a plurality of values using only one position adjustment volume 27.

In addition, the structure is such that the fertilization and seeding control by switching the work equipment switching volume 20 is activated only when the position lever 9 is operated to the highest position when the work part 11 is below near the ground surface. 11 from an intermediate position and the rising speed is not very fast,
It may be configured such that unnecessary rise control is not required.

In addition, as shown in FIG.
Measure the pressure at that point during the lifting operation of the working part 11.
Another embodiment will be described in which it is determined whether or not the fertilizing/seeding machine 13 is set to , and the mode is automatically switched to the fertilizing/seeding mode without providing a special mode.

The hydraulic pump 31 communicates with a tank 33 via a filter 32, a lift rod cylinder 36 via a priority valve 35, a hydraulic cylinder 34 for lifting and lowering a working part via a control valve 37, and further A pressure gauge 3 is installed in the head of the hydraulic cylinder 34.
9 has been installed. Note that 40 in the figure is an adapter.

Therefore, when the hydraulic cylinder 34 is actuated based on the operation of the position lever 9 to raise the working part 11, the pressure gauge 39
By measuring the pressure to the hydraulic cylinder 34 and determining the pressure, only the rotary work machine 12 can operate at the work section 1.
1 or the rotary work machine 12 and the fertilizing and seeding machine 13 are installed, and based on this, the switch to the fertilizing and seeding mode is automatically performed, making it possible to always maintain stable control. can.

Further, when the position adjustment volume 27 is operated in the fertilizing and seeding machine mode, the duty ratio reduction range of the pulse signal when the working part 11 is lowered can be changed as appropriate, and the central part of the volume 27 is set to a standard value. As well as the fourth
If the operation is counterclockwise in the figure, the duty ratio decrease width is set to a small value, and if the operation is clockwise, the duty ratio decrease width is set to a large value. Even if the weight of the working part 11 changes due to, for example, the weight of the working part 11 changes, the starting position of the feedback control starting from point j in FIG. 6 may be finely adjusted near the ground surface.

(G) As described in detail, according to the present invention, the working part (11) gradually decreases the duty ratio and ascends from the point when the working part (11) reaches a predetermined height based on the elevation angle detection means (19). reducing the speed and by means of feedback control means (28);
Since the control is configured to maintain a predetermined decelerated speed, simply by raising the position lever (9), the working part (11) can be quickly raised and stopped smoothly near the highest position. As a result, it is possible to reliably prevent an unpleasant shock when the working part (11) stops, thereby improving the operating feeling and improving the working efficiency.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an electric circuit according to the present invention, FIGS. 2 and 3 are overall side views showing a tractor to which the present invention can be applied,
Figure 4 shows the work equipment switching volume, etc. Figure 5 is a time chart showing changes in pulse signals when the working part is raised and lowered, Figure 6 is the pulse signal changes when the working part is raised and lowered. It is a time chart showing changes, etc. FIG. 7 is a diagram showing the hydraulic circuit. means

Claims (1)

[Claims] 1. In a mobile agricultural machine configured to raise and lower a working part by outputting a signal to a raising and lowering solenoid based on the operation of a position lever and operating a hydraulic actuator, the lifting angle detection detects the lifting angle of the working part. means, an actual speed calculating means for calculating an actual rising speed of the working part, and a duty ratio of an output signal to the lifting solenoid from the time when the working part reaches a predetermined height based on the lifting angle detecting means. a raising deceleration means that gradually reduces the ratio to reduce the rising speed; and a feedback control means that raises the working part at a constant speed based on the actual speed calculating means from the time when the duty ratio reaches a preset value. A working part control device for a mobile agricultural machine, comprising: and.