JPS61274604A - Earth working machine - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention provides a means for connecting a ground work device to a traveling vehicle body so as to be able to rise and fall and roll freely, and a means for raising and lowering the ground work device relative to the travel vehicle body; and a rolling control means for maintaining the ground working device in a set horizontal and horizontal tilted attitude relative to the ground, and detecting that the ground working device has been raised to a preset height of a non-working level with respect to the traveling vehicle body. The present invention relates to a ground working machine that is equipped with a control means that automatically corrects the posture of the ground working machine so that it is horizontally parallel to a traveling vehicle body, giving priority to rolling control.

[Conventional technology]

Conventionally, as a ground-based work machine with the above configuration, for example, there is one shown in Japanese Patent Application Laid-Open No. 57-71311, in which a limit switch is used to indicate when the lift arm of the work machine has reached the set height of the non-working level. The control system is configured to detect this and automatically correct the ground work device to be horizontally parallel to the traveling vehicle body.

[Problem that the invention seeks to solve]

However, the structure of the above cited device uses a limit switch to detect the level of the ground work equipment, so vibrations from the engine mounted on the vehicle body or vibrations during work may cause
Lift arm and limit switch are turned ON and OFF continuously
As a result, the ground working device is switched between the automatic correction side control state and the rolling control state in a short period of time, resulting in so-called hunting. In addition to limit switches, there are also ones that detect the level of ground work equipment by attaching a potentiometer to the lift arm and comparing the signal voltage from this potentiometer with a reference voltage using a comparator. Setting the level of the ground work equipment would cause the same inconveniences as described above.

The object of the present invention is to set the ground work equipment to any level by reasonable modification in a ground work equipment configured to switch between a rolling control state and an automatic correction control state, such as a spring-loaded ground work equipment. Even if the above 2.
The object of the present invention is to obtain a control means that does not switch between two control states.

[Means for solving problems]

A feature of the present invention is that in a ground work machine with a raised configuration, the ground work device is controlled in parallel and then returned to a rolling control state when the ground work device is lowered to a set height lower than the set height. The functions and effects are as follows.

[For production]

With the above configuration, for example, as shown in Fig. 1, when the lift arm (6) of the agricultural tractor rises and reaches the set height of the non-working level,
4) enters the automatic correction control state, and the lift arm (
6) is maintained at this set height, even if the lift arm (6) swings up and down due to vibrations of the vehicle body, the lift arm (6) remains at the set height. difference(
Since a set height (L3) lower than Ll) is not reached 1, the ground work equipment (4) is maintained in a self-correcting control state.

Further, when the ground work device (4) is lowered, the automatic correction control state is canceled only when the lift arm (6) reaches the set height of the lower level (1,).

〔Effect of the invention〕

Therefore, for example, if the control device is made up of a microprocessor, you can simply install the program, or if the control device is made up of a hard circuit, you can use a switching circuit with hysteresis such as a Schmitt circuit. By simply adding , a control means that does not cause hunting even when the ground work device is once raised to the set height during rolling control and maintained at the set height has been obtained.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in Figures 1 and 2, a bracket (2) is attached to the rear end of the traveling vehicle body (1) that can freely rotate around an axis (P) facing forward and backward, and at the rear of this bracket (2), the bracket (2) A pair of left and right links (3) that can move vertically and horizontally around the axis (Q)
, (3) are pivotally connected, and a rotary ground work device W (4) is attached to the rear end of the link (3), (3), and a hydraulic cylinder (5) is attached to the rear of the traveling vehicle body (1). A pair of left and right lift arms (6), (6) that can be driven up and down.
and the links (3), (3) are connected by a pair of lift ronds (7a), (7b), and further, a telescopic hydraulic cylinder (8) is interposed in one of the lift ronds (7b), This constitutes an agricultural tractor as an example of a ground working machine in which the ground working device (4) can be moved up and down and rolled.

In the agricultural tractor, the working device (4) is attached to the vehicle body (1).
) to an arbitrarily set position; rolling control to maintain the ground working device (4) in a set horizontal and horizontal tilted posture relative to the ground; and rolling control to maintain the ground working device (4) at a set plowing depth. 3. With automatic tillage depth control to maintain
Equipped with a control mechanism that allows two types of control.

That is, a boarding and driving section (9) is formed in the center of the vehicle body (1), and a seat (10) is provided in this driving section (9).
Two operating areas (X) located on the sides of the.

(Y) is provided with an operable lever (11), and a potentiometer (12) is attached to the base end of this lever (11). Further, a potentiometer (13) is attached to the lift arm (6) to detect its swing angle, and a sensor (14) is installed at the rear of the vehicle body (1) to detect the left and right inclination of the vehicle body (1). It is a provision. The hydraulic cylinder (8) installed in the lift arm (7b) is equipped with a stroke sensor (15) that detects the amount of expansion and contraction thereof, and the ground work device (4) is equipped with a stroke sensor (15) that detects the amount of expansion and contraction of the hydraulic cylinder (8). A sensor (16) for detecting the amount of movement is provided.

Furthermore, a control device (17) is provided on the side of the driving section (9).
There is a control box (18) with a
) includes a work selection switch (19) and a plowing depth setting device (20).
), a rolling angle setter (21), a plowing depth control sensitivity setter (22), and a switch (23) for forcibly raising the working device (4).

As shown in Figure 3, signals from each potentiometer, sensor, setting device, and switch are transmitted to the control device (1
7), the control device (17) operates the electromagnetic valves (VS) corresponding to the two hydraulic cylinders (5) and (8) based on these signals. has been configured.

By setting the lever (11) to any position in the operating range (X), the working device (4) will rise to the level relative to the vehicle body corresponding to this position, and the lever (11) will also be moved By setting to (Y), the working device (4) enters the automatic plowing depth control state. Further, the work selection switch (19) is set to a position (OFF) in which the control device (17) is not activated, a position (A) in which automatic plowing depth control is performed, and a position (R) in which rolling control is performed.
), and a position (A-R) where automatic plowing depth control and rolling control are performed simultaneously.

The tillage depth sensitivity setting device (22) is also used as a switch to arbitrarily raise or lower the working device (4), and is set to the position (D),
By operating (M) and (U), the working device (4) is lowered, placed in a neutral state, and raised, respectively. When the forced lift switch (23) is pressed, the lamp (23a) inside the switch lights up and at the same time raises the working device (4) to the upper limit, and when pressed again, the lamp (23a) turns off. Moreover, the working device (4) returns to its original control state.

Further, the control device (17) is configured such that the working device (4) is connected to the vehicle body (
1), when the height rises above the set height of the non-working level, the working device (4) is moved to the vehicle body (1) by rolling control.
Even if the vehicle body is tilted relative to the vehicle body, automatic correction control is performed so that the working device (4) is horizontally parallel to the vehicle body (1), giving priority to rolling control.

Here, the level at which the working device (4) is raised and the automatic correction control is activated is determined as (L,) based on the swinging position of the lift arm (6). Detection of this level is performed using the potentiometer (13) attached to the lift arm (6).
done by.

Further, after entering the automatic correction control state, the working device (4)
When lowering, the height (L1) is lower than the set height (L1).
L2), the automatic correction control is canceled and the control device (17
) is activated and, for example, when the height of the working device (4) is set to a specific level, such as when automatic correction control and rolling control are switched at a specific level, the vehicle body (1) The working device (4) swings up and down due to the vibration from
.

The so-called control switches between the two types of control in a short period of time.
Efforts are being made to prevent hunting.

Furthermore, the manner in which the automatic correction control is activated (0'J) L and the operating force is released (OFF) is explained based on the level of the working device (4) as shown in the graph shown in Fig. 4. , during the upward stroke shown by the solid line, the working device (4) moves (
Hysteresis is set so that the working device (4) becomes the (ON) state when it rises to Ll), and becomes the (OFF) state only when the working device (4) descends to (L2) during the downward stroke shown by the broken line. .

The control device (17) is configured to operate by determining conditions using a microprocessor, and the automatic correction control is performed according to the flowchart shown in FIG.

〔Example〕

In addition to the embodiments described above, the present invention also provides a control device (17), for example.
The working device ( 4) may be configured to be automatically corrected.

[Brief explanation of drawings]

The drawings show an embodiment of the ground work machine according to the present invention, in which Fig. 1 is a side view of the rear part of an agricultural tractor, Fig. 2 is a schematic rear view of the agricultural tractor, Fig. 3 is a schematic diagram showing the control system, and Fig. 4 is a schematic diagram showing the control system. The figure is a graph showing the level at which the automatic correction control operates, and FIG. 5 is a flowchart for operating the automatic correction control. (1)...... Traveling vehicle body, (4)... Ground work device, (L,)... Set height of non-working level, (Lz) -... ...Setting height to return to rolling control.

Claims (1)

[Claims] A means for connecting a ground work device (4) to the traveling vehicle body (1) so as to be able to rise and fall and roll freely, and for raising and lowering the ground work device (4) with respect to the traveling vehicle body (1);
and a rolling control means for maintaining the ground work device (4) in a predetermined left-right tilted attitude relative to the ground, and the ground work device (4) is set at a set height (non-work level) with respect to the traveling vehicle body (1). When it is detected that the ground work device (4) has been raised above L_1), it is equipped with a control means that gives priority to rolling control and automatically corrects the posture of the ground work device (4) so that it is horizontally parallel to the traveling vehicle body (1). The ground work device is configured to return to the rolling control state when the ground work device (4) is parallel controlled and then lowered to a set height (L_2) lower than the set height (L_1). Ground work equipment.