JPS6332410A - Draft control apparatus of earth working machine - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a draft control device for a ground work machine that is towed by a tractor or the like, and in particular, the invention relates to a draft control device for a ground work machine that is towed by a tractor or the like. The present invention relates to a draft control device for a ground-based working machine that can apply a small lifting force to the ground-based working machine.

[Conventional technology]

Conventionally, the raft control device for this type of ground-based work machine automatically raises and lowers the ground-based work machine so that the plowing depth set by the operator is maintained. The hydraulic lifting mechanism is controlled to move up and down based on the difference between the draft detection value and the depth (drag) setting value, and the lift arm is moved up and down by -2.

[Problem that the invention seeks to solve]

However, when the plowing depth (drag) setting value and the current plowing depth (drag) are balanced in the draft control described above, draft control is not performed, and if this balanced state continues for a certain period of time, Since only a portion of the weight of the machine acts on the drive wheels, the frictional force of the drive wheels decreases, causing slippage, which may reduce the tractive force of a towing vehicle such as a tractor. When this slip occurs, the drive wheel tries to rotate more lightly or faster than when it is in a balanced state, so the control unit sends a draft lowering operation command to the work machine based on the input from the draft sensor. During the work, the plowing depth (drag) setting and the plowing R (drag), which were at the appropriate white position, change to a state in which the descending output continues, and this continues for a certain period of time or more.

Furthermore, when plowing a field with gentle unevenness, if the rear wheels run over a convex part, the weight of the plow will be more on the front wheels and less on the rear wheels. Since the top link remains in the top link, a tensile load, that is, a negative torque, is applied to the top link, so a descending command is issued from the control unit to balance it, causing the rear wheels of the towing vehicle to slip and causing a loss of traction force. There are times when I get caught.

Therefore, a problem arises that needs to be solved in order to apply a predetermined traction force to the towing vehicle in such a state.

[Means for solving problems]

The present invention has been proposed in view of the above-mentioned problems, and provides an agricultural machine equipped with an electro-hydraulic mechanism.
When the ground work equipment does not rise for a certain period of time when traveling with a draft load set by raft control,
It is an object of the present invention to provide a draft control device for a ground working machine, characterized in that a rising signal is output from the control section to apply a small rising force to the ground working machine.

[Effect]

In the present invention: - When draft work is being carried out, the plowing depth (drag force) set value and the draft sensor value substantially match, and this state continues for a certain period of time, or when the field is rough. If the rear wheel of the towing vehicle rides on a convex part, the electro-hydraulic mechanism does not raise or lower the ground work equipment, and if this state continues for a certain period of time, this state is determined by the control unit, and the control unit outputs a command signal to the hydraulic mechanism to raise the pressure.

As a result, a small lifting power is applied to the ground-based working machine, and the work efficiency of the ground-based working machine is increased without reducing the traction force.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings. Incidentally, for the convenience of explanation, the configurations that belong to the conventional public scent will also be explained at the same time.

@2 As shown in Figure 2, a tractor (1) as a towing vehicle
At the rear of the machine, attach a ground work device (2) such as a plow to a pair of left and right lift arms f3) + 33, and connect the left and right lift arms (4).
The left and right lower links (5) swing up and down via (4).
) (5) and a top link (6) at the upper center of the work equipment link (7), and this work equipment connection link (7) is connected to its lift arm (31 (3)
It is configured to be lifted and lowered by a hydraulic elevator (9) which is rotated up and down by a lift cylinder (8) using hydraulic pressure. In addition, on the supply/discharge side i of pressure oil to the lift cylinder (8), operation commands from a control unit a0 constituted by something like a microcomputer are amplified by the ascending drive unit αυ or the descending drive unit 11z. The ascending proportional solenoid valve fi3 or the descending proportional solenoid valve (14
) to open and close the lift cylinder (8).
) is supplied with pressure oil from pump Q5 to the lift arm (3).
) (3) is raised, or the pressure oil in the lift cylinder "8" is discharged and the lift arm (3H3) is lowered.

Furthermore, there is a position lever (Is) installed near the cockpit.
) and position meter detection axis with the lift arm (3
) and the lift arm angle sensors (S) formed by connecting them to the control unit α [@ position lever (I+)].
) so that the height detection value detected by the lift arm angle sensor (Sl) matches the setting value set by the operation of the lift arm angle sensor (Sl).
Alternatively, the output is output to the lowering drive unit α, thereby controlling the elevation, and the draft sensor (Sl) that detects the tillage resistance is used, for example, as a draft sensor (Sl) connected to the front part of the top link (6). For example, a potentiometer 11Fj is used to detect the amount of movement of the rod αe forward due to the plowing resistance force against the draft spring Uη, but the draft sensor (Sl) should not be limited to this. do not have.

Furthermore, a plowing depth (drag force) setting 1I2) is provided near the cockpit, and the plowing resistance detected value detected by the draft sensor (s2) is adjusted to the plowing resistance setting value set by operating the plowing depth (drag force) setting 1I2). In order to match, the control unit should be connected to Ihl and other ground work equipment (
Kf4 is configured so that an operation command is issued to the ascending drive section (ID) and the descending drive section (13) so that draft control can be performed by these in order to perform the ascending/descending operation of the machine 2).

Further, the ascending proportional solenoid valve a3 and the descending proportional solenoid valve (141) may be commonly used ones.

Therefore, a tractor (1) having such an electro-hydraulic mechanism
), the tillage depth (drag) setting device (I
There are times when the plowing depth (drag force) set value set in step 2) and the draft sensor value detected by the draft sensor (S2) substantially match. At that point, since there is no input to the control unit a1, no lifting command is output from the control unit Ql, and therefore the ground work machine (2) does not perform any lifting or lowering operations. In such a case, the rear wheels of the tractor (1) slip, and the tractive force of the tractor (1) decreases. Therefore.

In such a situation, when working with the draft load set, the plowing depth (drag force) setting value and the draft sensor value substantially match and continue for a certain period of time (for example, 10 to 15 seconds) or more. This is done by outputting a small ascending signal command and applying a slight ascending force to the ground work machine (2) through the ascending proportional drive unit port υ according to the command of the program pre-installed in the control unit 00. , to produce the effect of weight transfer to the rear wheels of the tractor (1). A slight load is then applied to the rear wheels of the tractor (1), allowing it to travel without reducing its traction force. This operating procedure can also be understood by referring to the flowchart in FIG. 3 of the appendix.

Furthermore, during draft work by the tractor having an electro-hydraulic mechanism, the plowing depth (drag force) setting value and the draft sensor value may continue to descend at appropriate positions. This is because during the above-mentioned work, when the tractor (1) travels over the undulations, the wheels then ride on the convex surface, so that the weight of the machine is mostly applied to the front wheels, and the weight of the rear wheels is reduced. At the same time, since the plow machine remains underground, a tensile load, which is a draft force in the negative direction, acts on the top link, and the draft sensor value temporarily changes from the plowing depth (drag force) setting device ( The value may be smaller than the plowing depth (drag force) setting value set by I2). In other words, even though the load is actually acting on the plow,
The control unit α1 outputs only a descending command based on this apparent negative draft value, and as a result, the traction resistance of the tractor (1) increases, the load on the rear wheels decreases, and the work machine is further lowered. I ended up slipping because of the
In other words, it stops moving forward. Therefore, the plowing depth (drag) setting device (I
2) If the load fluctuates to the downward side with respect to the plowing depth (drag force) setting value set by According to the commands of the program, a small upward output is periodically output during the downward output to prevent the tractive force of the tractor (1) from decreasing, and to easily overcome ups and downs to improve work efficiency. It is. This operating procedure can also be fully understood by referring to the flowchart in FIG. 4 of the appendix.

〔Effect of the invention〕

As described in detail in the described embodiment, the present invention operates when the draft control is activated when the plowing depth (drag force) setting value and the draft senna value continue to substantially match for a certain period of time during the draft operation. Even when the tractor is not being sharpened, a small lifting power is applied according to the commands of a pre-installed program to make the weight transfer work effectively, or when the tractor is traveling on an uneven surface and performing draft work, the tractor If the rear wheels run up on the convex surface and a descending command is output from the control unit even though the ground work machine is not actually descending, the traction resistance becomes large and the rear wheels run on the convex surface. However, if only this lowering command continues for a certain period of time, a small upward output is periodically output on the way down, giving traction force to the tractor, and so on. It was possible to prevent the reduction in traction force, easily overcome the extremely depressed surface, and improve work efficiency.

[Brief explanation of drawings]

The figures show embodiments of the present invention, with Figure 1 being a control circuit diagram and Figure 2 being a control circuit diagram.
The figure is a side view of the tractor, and Figures 3 and 4 are flowcharts of each embodiment. Code explanation

Claims (1)

[Claims] A draft sensor detects the draft of a ground work machine that can be raised and lowered by a hydraulic lifting mechanism, and
A draft having a plowing depth (drag force) setting device for setting the plowing depth (drag force), and a control unit configured to control the hydraulic lifting mechanism to raise and lower so as to perform a lifting operation according to the difference between the above two values. In the control device, when the ground work machine is running with a draft load set by draft control, and the ground work machine does not rise for a certain period of time, the control unit outputs a rise signal, A draft control device for a ground-based work machine, characterized in that a small lifting force is applied to the ground-based work machine.