JPH0797923B2 - Agricultural tractor work implement control method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to control of a working machine installed at a rear portion of an agricultural tractor for performing a plowing work on the ground.

(Prior Art) Plowing work is performed by providing a working machine 3 which is moved up and down by raising and lowering a lift arm 2 at the rear part of an agricultural tractor 1 and pressing the working machine 3 against the ground, as shown in FIG. . The operator inputs a plowing depth position suitable for the ground using the lift arm position setting device, and supplies the amount of oil corresponding to the set position to the lift arm elevating cylinder S ₁ by the lift arm control mechanism to elevate the lift arm 2. To determine the working depth of the working machine.

Then, when the control of the working machine is started, the deviation between the current position of the lift arm and the set position is obtained, and when the deviation is large, the operation of the lift arm is not performed, thereby preventing the unexpected movement of the working machine.

(Problems to be Solved by the Invention) However, in the conventional example, the lift arm 2 is provided only when the work implement control is started after the power switch of the agricultural tractor 1 is turned on.
Since the deviation between the current position and the set position of is calculated and the working machine is controlled, there are the following problems.

For example, as shown in FIG. 3, when the engine stops due to the resistance of the soil during the plowing work at the height of h ₁ where the actuator is set, the lever of the setting device is operated for some reason at this time.
The When was supposed to set the height of h _2, has occurred operations work machine 3 unexpected that moves from h ₁ to the height of h _2.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a work machine control method for preventing malfunction of a work machine of an agricultural tractor.

(Means for Solving Problems) In order to solve the above problems, the present invention relates to a work control for moving a working machine provided at a rear part of an agricultural tractor up and down by lifting and lowering a lift arm by a lift arm control mechanism. The current position of the lift arm is detected from the arm sensor, and the lift arm height setter sets the set position of the lift arm for the target working depth. By storing the start and detecting the current rotation and stop of the engine by the engine sensor based on this storage, it is possible to detect the case where the engine is stopped during the work control and the case where the engine is started during the work control. In each case, the deviation between the current position of the lift arm and the set position is calculated, and the deviation is preset. When in less than a value performs a control for lowering the working machine by the lift arm control mechanism, is larger than the value which the deviation is set in advance is characterized by prohibiting the control of the working machine by the lift arm control mechanism.

Further, the engine sensor determines whether the engine is rotating or stopped by detecting the actual engine speed.

(Operation) As described above, the present invention obtains the deviation between the current position of the lift arm and the set position when the power switch of the agricultural tractor is turned on, when the engine is started or stopped during work control, If there is a deviation, the work machine is not operated.

(Example) An example of the present invention will be described with reference to the drawings.

FIG. 1 shows a block diagram of the embodiment.

The lift arm sensor 4 detects the current position of the lift arm 2. The lift arm height setting device 5 is for setting the height of the lift arm 2 at which the operator maintains the plowing depth position suitable for the ground. The engine sensor 6 detects the actual rotation speed of the engine of the agricultural tractor, and detects whether the engine is operating or stopped.

Signals from the lift arm sensor 4, the lift arm height setter 5, and the engine sensor 6 are input to the lift arm control mechanism 7, where the lift arm 2 is moved to a target set position. The stroke amount of the arm lifting cylinder S ₁ is determined, and the lift arm 2 is lifted and lowered by supplying oil for moving the stroke amount to the cylinder S ₁ , and the working machine 3 is maintained at the set plowing position.

FIG. 2 shows a flowchart of the control method.

After detecting that the power switch of the agricultural tractor has been turned on, the position of the lift arm 2 in operation is detected by the lift arm sensor 4 and this value is input, and the lift arm height setting device 5 makes it possible for the operator to adjust to the ground The height of the lift arm 2 at the working depth position is set, and this value is input. The current position of the lift arm 2 and the set position are compared, and if the deviation between the two is larger than a preset value, it is determined that there is a deviation,
The control of the work implement 3 is prohibited because the work implement 3 may perform an unexpected operation of the worker. A dead zone is provided so that it is not necessary to operate the working machine 3 when the current position of the lift arm 2 and the set value match or are extremely close to each other. Therefore, the preset value for determining whether there is a deviation is a value in which the dead zone has a certain width.

If there is no deviation, the engine sensor 6 determines whether the engine is rotating. If the engine is running, remember that the engine is starting. Next, the lift arm 2 is operated to the set position, and the work implement 3 is controlled to maintain the working depth position.

Then, it is determined again whether the engine is rotating.
From the result at this time and the memory of the previous engine start, it is possible to determine whether the engine is started or stopped during the work control. That is, when the engine is rotating here and the engine start is not stored, the engine is started during the work control. Further, when the engine is stopped here and the engine start is stored, the engine is stopped during the work control.

If the engine starts or stops during work control,
As an abnormal situation, the deviation between the current lift arm position and the set position is obtained again, and when there is a deviation, the work control is prohibited.

When the engine is not started or stopped during the work control, the work control is continued and the lift arm 2 is maintained at the set position.

That is, when the engine rotates or stops during the work control, the deviation between the current position of the lift arm 3 and the set position is obtained again to determine whether to perform the work control. Prevent unexpected behaviors.

For example, when the working machine 3 is performing plowing work at the height of h ₁ in FIG. 3 and the engine is stopped, or when the engine is not started during work control and the working machine 3 is lowered to the height of h ₁ , For some reason, even if the height adjuster of the lift arm 2 is set to the height of h ₂ for some reason, the current position h ₁ and the set position h _{2 of the} lift arm 2 are set.
Therefore, the work implement 3 is not controlled and the work implement 3 does not move.

At this time, the operator can predict the operation of the working machine 3 by temporarily setting the lift arm height setter 5 to the height of h ₁ and then setting the required lift arm height. It is possible to prevent an unexpected operation of the work implement 3.

(Effects of the Invention) As described above, the present invention is provided when the engine is stopped after the power switch of the agricultural tractor is turned on or during work control.
Alternatively, when the engine is started during work control, the deviation between the current position of the lift arm and the set position is obtained, and when the deviation is smaller than a preset value, the work machine is controlled by the lift arm control mechanism, and the deviation is large. In this case, the control of the working machine is prohibited, so if you want to move the working machine when there is a deviation, it is necessary to adjust the height of the setter to the current lift arm position, and predict the movement of the lift arm. Therefore, it is possible to prevent the worker from unexpectedly operating the work machine.

In addition, the rotation and stop of the engine of the agricultural tractor memorize the engine start, and the current state is also judged by the engine sensor based on this memory, so not only when the engine is started, but also when the engine is stopped during work control or It is possible to reliably detect the start-up, and it is possible to reliably avoid an unexpected operation of the working machine by the operator.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a flow chart of the embodiment, and FIG. 3 is a side view of an agricultural tractor. 1 …… Agricultural tractor 2 …… Lift arm 3 …… Working machine 4 …… Lift arm sensor 5 …… Lift arm height setter 6 …… Engine sensor 7 …… Lift arm control mechanism S ₁ …… Lift arm Lifting cylinder

Claims (2)

[Claims] 1. A working machine provided at the rear of an agricultural tractor,
In the work control of lifting and lowering the lift arm by the lift arm control mechanism, the lift arm sensor detects the current position of the lift arm and the lift arm height setter sets the set position of the lift arm to the target working depth. The engine was stopped during work control by detecting after the power switch of the agricultural tractor was turned on, storing the engine start of the agricultural tractor, and judging the current rotation and stop of the engine by the engine sensor based on this memory. In this case, the case where the engine is started during the work control is detected, the deviation between the current position of the lift arm and the set position is obtained in each of the above cases, and when the deviation is smaller than a preset value, The lift arm control mechanism controls the work machine up and down, and the deviation is a preset value. Work machine control method for agricultural tractors, characterized in that prohibiting control of the working machine by the lift arm control mechanism is greater Ri. 2. The work machine control method for an agricultural tractor according to claim 1, wherein the engine sensor determines whether the engine is rotating or stopped by detecting an actual engine speed.