JPH0441821A - Loader control device - Google Patents

Abstract

PURPOSE:To simplify control of the attitude of a bucket by judging the angle of bucket in conformity to a command given from an automatic horizontal grounding command means, and if in the dumped state, performing sinking and scooping of the lift arm and bucket after scooping correction motion, or merely performing sinking. CONSTITUTION:To start automatic horizontal grounding, an auto horizontal grounding mode switch 32 is put on, and an operational lever 29 in a switch box 30 is turned into the downward scoop position. At this time, a subprogram for automatic horizontal grounding is started by an auto horizontal grounding command means 101. A bucket state judging means 102 judges whether the angle of bucket 4 is on the scoop side or dump side by reference to the comparative setting valve (m). A scoop correcting means 103 gives a command to a bucket driving means, and the scoop correcting motion is performed until the correction angle set value (n) is attained. Then a downward/down-scoop command means 104 gives a downward command to an arm driving means, or gives a scoop command. When the lift arm 3 attains the grounding position, an at-grounding dump/scoop means 105 revolves the bucket 4 into the horizontal grounding state.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a loader control device for an agricultural front loader or the like installed in a work vehicle such as a tractor.

[Conventional technology]

Agricultural front loaders have a bucket attached to the tip of a lift arm, and are generally operated manually, with a control lever controlling electromagnetic valves in the hydraulic system for driving the lift arm and the bucket. In other words, by adjusting the angle of the control lever on the switch box forward, backward, left and right, you can raise and lower the lift arm and dump the bucket.

Have them do things like scooping. It also has the ability to simultaneously lower and scoop, as well as raise and dump.

[Problem to be solved by the invention]

Typically, the loader scoops up the load, lifts it, releases it, lowers the lift arm back to the ground position, returns to the scooping position, and moves on to the next task.

Repeat this.

In this case, it is necessary to set the scooping posture each time using a human sense, and the posture will be different each time it is set repeatedly. Therefore, there are problems in that work efficiency is poor and operations are complicated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a loader control device that can be controlled with a simple operation so that the bucket always maintains a predetermined posture when returning the bucket to the scooping posture of the grounding position.

[Means for Solving the Problems] The present invention provides a loader control device used in a loader, in which a bucket driven by a bucket drive means for scooping and dumping is attached to the tip of a lift arm rotationally driven by an arm drive means. The following means are provided.

That is, as shown in FIG. 1, automatic horizontal grounding command means (101), bucket status determination means (102), rake correction means (103), lowering/descending rake command means (104), and A dump rake means (105) is provided.

[For production]

The automatic horizontal grounding command means (101) gives a command to horizontally ground the bucket, and the bucket state determination means (102) responds to the command from the command means (101) to determine whether the angle of the bucket is set by comparison ( It is determined whether the angle is at the rake angle or the dump angle than i(m).

If the dump angle is at the dump angle, the rake correction means (103) gives a command to the bucket drive means to set the correction angle setting value (
The rake correction operation is performed until n) is reached.

After this rake correction operation, the descending/descending rake command means (
104) gives a lowering command to the arm driving means, or gives a rake command to the bucket driving means together with this lowering command.

If the determination result by the bucket state determining means (102) is that the bucket is in the rake state, the lowering/lowering rake command means (104) issues the lowering command without performing the rake correction.
Or give both a descent command and a sweep command.

When the lift arm reaches approximately the grounding chamber, the dump and
A dump or rake command is given to the bucket drive means by the rake means (105) to rotate the bucket to a horizontally grounded state.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 1 to 7.

As shown in FIG. 3, the loader 1 has a lift arm 3 attached to a base 2 so as to be rotatable up and down, and a bucket 4 attached to the tip of the lift arm 3 so as to be rotatable for dumping and scooping. It is removably mounted on a work vehicle 5 such as a tractor via the vehicle. An arm drive means 6 is provided between the base 2 and the lift arm 3, and a bucket drive means 8 is provided between the lift arm 3 and the bucket 4 via a link 7.

Each drive means 6.8 consists of a double-acting hydraulic cylinder,
An arm sensor 35 and a bucket sensor 36 are attached to detect the angles of the lift arm 3 and bucket 4 based on the piston position.

FIG. 2 shows a loader control device. The control section 9 is composed of a microcomputer, and a memory 10, an input/output port I10, an interrupt control means 11, etc. are connected to a central processing unit CPU via a bus. The input boat of the input/output port 10 has a switch box 30 having an operation lever 29.
are connected via an A/D converter 31, and further connected to a mode switch group 32, a data input means group 33, an arm sensor 35 of the loader 1, and a bucket sensor 36. Loader 1 is installed on the input/output capo-Hlo output boat.
A hydraulic control system 34 is connected thereto.

In the control program area 12 of the memory 10, in addition to the main program, various control means 13 to 22 consisting of sub-programs of control sequences are written. In addition, control means (not shown) for giving commands to the hydraulic control system 34, such as raising and lowering the lift arm 3, scooping and dumping the bucket 4, in response to input from the switch box 30, is also written in the control program area 12. It is. memory 1
Among the control means 13 to 22 of 0, the automatic horizontal grounding means 1
3 will be explained in detail later, and the remaining means 14 to 22 will be explained briefly later.

The data area 23 of the memory 10 includes a storage area 2 that stores set values of the upper and lower limit angular positions of the lift arm 3.
4.25, a storage area 26 for the arm automatic horizontal grounding limit h which is the lowering limit position when the lift arm 3 is automatically horizontally grounded, and storage areas 2728 for the bucket offset and bucket squill limits.

The motor switch group 32 is means for selecting each of the control means 13 to 22 in the control program area 12, and includes an automatic horizontal grounding mode switch 39, a load collapse prevention mode switch 40, and various modes represented by reference numeral 41. Equipped with a switch.

The data input means group 33 is a means for inputting each data to be input into the data area 23, and includes a large number of data input means represented by reference numeral 43 in addition to means 42 for setting the arm automatic horizontal grounding limit (h). .

These input means 42 and 43 are composed of, for example, a volume that provides an analog signal of a voltage value, an A/D converter that converts this voltage value into a digital value, or a numeric keypad, an input mode selection key, etc. .

The hydraulic control system 34 includes a tM1 valve with a direction switching function provided in the hydraulic path of the arm drive means 6, and a bucket drive means 8.
It is equipped with a rake installed in the hydraulic path, and a solenoid valve with a three-position switching function for dump and speed-up dump. The hydraulic control system 34 also includes an arm drive means 6 when dumping the bucket 4 and raising and lowering the lift arm 3 at the same time.
A solenoid valve is provided which connects the hydraulic path of the bucket drive means 8 and the bucket drive means 8 in series. Further, the hydraulic control system 34 includes a controller (not shown) that pulse-width modulates the output from the human output boat 10 of the control section 9 and outputs it to each of the electromagnetic valves.

The switch box 30 changes the resistance value of the variable resistor or the capacitance value of the variable capacitor by tilting the operating lever 29 from the neutral position, and outputs a voltage signal.As the tilt angle increases, the output voltage increases. The value becomes higher. The voltage signal is input to the input/output port r10 via an AD converter or the like. The variable resistors or variable capacitors are provided in the number corresponding to each position of the control lever 29, which will be explained next with reference to FIG. 4, and various control operation signals are outputted depending on the direction of inclination. The voltage value due to the inclination of the operating lever 29 can be adjusted by a sensitivity switching means 37 consisting of a variable resistor, a switch, or the like.

FIG. 4 shows the types of operations depending on the direction in which the operating lever 29 of the switch box 30 falls. When the lever position changeover switch 38 in FIG. 2 is turned on, each operation in FIG. 0 where each operation in figure (B) is performed
For example, when the lever position changeover switch 38 is in the on state, when the operating lever 29 is tilted forward, an operating output is given to the t magnetic valve terminal in the lowering direction of the lift arm, and when tilted diagonally forward and to the right, the operating output is applied in the lowering direction of the lift arm. is output to each solenoid valve terminal in the bucket dump direction. When the lever position changeover switch 38 is in the OFF state, as shown in FIG. 4(B), when the operating lever 29 is tilted forward, the t-magnetic valve outputs of lowering and rake are obtained. In addition, FIG. 4(A).

In either case (B), when the operating lever 29 is tilted to the right more deeply than a predetermined angle, an operating output such as speed-up dumping shown in the rightmost column of the figure is obtained.

Further, the output in the right column is made effective only when the lever sensitivity switching means 37 is in the speed increasing position.

Next, the detailed configuration of the automatic horizontal grounding means 13 (FIG. 2) will be explained along with the operation of the loader control device.

FIG. 5 shows four basic postures of the bucket 4, and in the following description, these basic postures will be referred to as follows.

As shown in FIG. 5(A), when the bucket 4 is in contact with the ground 45, it is called "absolute horizontal".As shown in FIG. The position of the bucket 4 where the bottom surface 4a of the bucket 4 is parallel to the ground 45 is called "parallel horizontal".As shown in the same figure (C), when only the lift arm 3 is raised or lowered from the absolute horizontal position The position of bucket 4 is called “relative horizontal” (
As shown in D), regardless of the position of the lift arm 3,
The position of the bucket 4 where the opening surface 4b of the bucket 4 is horizontal to the ground 45 is called "opening surface horizontal."

The automatic horizontal grounding means 13 shown in FIG. 2 will be explained.

As shown in FIG.
This is a control means that automatically performs an operation of touching the ground so that b is parallel to the ground 45.

To start the automatic horizontal grounding control operation, turn on the automatic horizontal grounding mode switch 32 (FIG. 1) and place the operating lever 29 of the switch box 30 in the downward rake position. This starts the automatic horizontal grounding subprogram.

The automatic horizontal grounding command means 1 shown in FIG.
01 is configured. Note that when the operating lever 29 is released, it returns to the neutral position. When the operating lever 29 enters a position other than the descending rake and neutral position, the interrupt control means 11 shown in FIG. It will be done.

An overview of automatic horizontal grounding operation will be explained. When the automatic horizontal grounding operation starts, the attitude of the bucket 4 at that time is first determined. The automatic horizontal grounding program consists of subprograms A to C, and these subprograms A to C are selected depending on the following conditions.

As shown by the solid line in FIG. 7(A), when the bucket 4 is located on the dump side rather than the parallel horizontal line shown by the chain line, it is controlled by the automatic horizontal grounding subprogram A. As shown by the solid line in FIG. 7(B), when the bucket attitude is on the rake side rather than the parallel horizontal plane and on the dump side rather than the relative horizontal plane C, it is controlled by the automatic horizontal grounding B subprogram. If it is on the rake side than the relative horizontal C, it is controlled by the automatic horizontal grounding C subprogram. The step of determining relative horizontality constitutes the bucket state determining means 102 (FIG. 1), and the relative horizontal angle becomes the comparison set value m.

The sequence of automatic horizontal grounding A will be explained. This sequence operates when the bucket 4 is dumped more than parallel to horizontal, as described above with reference to FIG. 7(A). To explain its basic operation, the lift arm 3 first scoops the bucket 4 until it is parallel and horizontal, and then performs a downward scooping operation after detecting the parallel horizontal position. ) When descending to point h, the descending is stopped, the bucket 4 is dumped or scooped to the absolutely horizontal ground position, and the output is stopped. In addition, arm automatic horizontal grounding limit) h is the lift arm 3 when it becomes absolutely horizontal.
The angle is set as appropriate by the user using the arm automatic horizontal grounding limit input means 33 shown in FIG. Further, the bucket offset is similarly set appropriately by the user so that the bucket 4 stops at an absolutely horizontal position.

The sequence of automatic horizontal grounding B will be explained. This sequence operates when the bucket 4 is on the rake side rather than the parallel horizontal plane and on the dump side rather than the relative horizontal plane C, as shown in FIG. 7(B). To explain the basic operation, the scoop output is performed until the bottom surface 4a of the bucket 4 reaches the relative horizontal level C, and then the arm is output downward, and when the arm automatic horizontal grounding limit h is reached, the output is stopped.

The sequence of automatic horizontal grounding C will be explained. This sequence operates when the bucket 4 is on the rake side with respect to the relative horizontal C as shown in FIG. 7(C). To explain the basic operation, in this case, the bucket angle is not corrected, the bucket angle is not corrected, and the descending rake is performed, and when the arm reaches the automatic horizontal grounding limit h as shown in Figure 7 (D), the absolute level d
Dump output is performed until the end, and then the output is stopped.

In addition, by each of the above-mentioned sweep output steps in the automatic horizontal grounding subprograms A and B, the sweep correction means 103
(FIG. 1) is configured, and the descending/descending sweep command means 104 is constituted by each descending/squeezing output and descending output steps in the automatic horizontal grounding subprograms A to C. Further, dump/squeeze means 105 at the time of ground contact is configured by each step of dump or rake output and dump output in the automatic horizontal grounding A to C subprograms.

According to this loader control device, it is determined whether the angle of the bucket 4 is at the rake angle or the dump angle than the relative horizontal C, and if it is in the dump state, the rake correction operation is performed and then the lift arm 3 and bucket 4
When the bucket 4 is returned to the scooping position of the ground position,
Always maintains a predetermined horizontal ground posture. Moreover, the above-mentioned horizontal grounding operation can be performed simply by turning on the automatic horizontal grounding mode switch 39 and placing the operating lever 29 in the downward scoop position, making the operation easy. Further, when performing a descending rake, the hydraulic paths of the arm drive means 6 and the bucket drive means 8 are connected in series, so that the descending operation can be performed quickly.

Next, the control operations of each of the control means 14 to 22 in the control program area 12 of FIG. 2 will be briefly explained. The cargo collapse prevention means 14 controls so that the opening surface 4b of the bucket 4 does not face toward the work vehicle 5 side rather than the ground 45 even when the lift arm 3 moves up and down. When lifting the lift arm 3 and scooping the bucket 4 at the same time, the lifting rake means 15 performs the rake operation until the opening surface 4b of the bucket 4 becomes horizontal, and then changes to the lifting and dumping operation. The automatic parallel lifting means 16 controls the bucket 4 to maintain a constant angle with respect to the ground when the lift arm 3 moves up and down. When the lift arm 3 and the bucket 4 are in a stopped state, the self-holding means 17 controls the lift arm 3 and the bucket 4 so that even if the elevation position or the bucket angle changes due to some fluctuation factor, the position before the change is maintained. The automatic return means 18 stores an arbitrary posture and returns to the memorized posture from another arbitrary posture. The buffer stop means 19 is a means for applying a buffer stroke when the lift arm 3 and bucket 4 are stopped. The playback means 20 teaches an arbitrary movement and causes the movement to be repeated. Ascent position regulating means 21 and descending position 1 regulating means 2
2 is means for limiting the upper and lower limits of the lift arm 3 to the values stored in the arm upper limit 24 and arm lower limit 25 of the data area 23.

In the above embodiment, when performing automatic horizontal grounding, there are two cases: when the bucket 4 is on the dump side rather than the parallel horizontal plane, and when it is on the rake side rather than the parallel horizontal plane and on the dump side than the relative horizontal plane C. Although the control operations are different, they may be the same. Further, the comparison setting value m for determining the necessity of correcting the bucket attitude before descending does not necessarily have to be the angle of the relative horizontal C.

Further, in the above embodiment, the output of the switch box 30 of the operation lever 29 is always inputted to the control section 9 consisting of a microcomputer. The output of the box 30 may be input directly to the hydraulic control system 34.

〔Effect of the invention〕

The loader control device of the present invention determines whether the angle of the bucket is at the rake angle or the dump angle than the comparison setting value by a command from the automatic horizontal grounding command means, and if it is in the dump state, performs the rake correction operation. After doing this, the lift arm and bucket are lowered, scooped, or lowered, so when the bucket is returned to the scooping position at the ground position, it can be controlled with a simple operation so that it is always in the specified position. It has the effect of being able to

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the configuration of the present invention, Fig. 2 is a block diagram showing a loader control device according to an embodiment of the invention, Fig. 3 is a side view showing the loader, and Fig. 4 is a diagram of the operating lever of the same. Fig. 5 is an explanatory diagram of the operating position, Fig. 5 is an explanatory diagram showing each basic posture of the bucket, Fig. 6 is an explanatory diagram of the general operation of automatic horizontal grounding, and Fig. 7 is an explanatory diagram of the automatic horizontal grounding operation. be. DESCRIPTION OF SYMBOLS 1... Loader, 2... Base, 3... Lift arm, 4... Bucket, 5... Work vehicle, 6... Arm drive means, 8... Bucket drive means, 9 ...Control unit, 12...Automatic horizontal grounding means, 29...Operation lever, 30...Switch box, 32...Automatic horizontal grounding mode switch, 33...Arm automatic horizontal grounding limit input means , 34...hydraulic control system, 101...
Automatic horizontal grounding command means, 102...Bucket status judgment means, 103...Squeeze correction means, 104...Descent/lower rake command means, dump/swee means upon landing, Fig.

Claims (1)

[Scope of Claims] A loader control device for use in a loader, in which a bucket driven by a bucket drive means for scooping and dumping is attached to the tip of a lift arm that is rotatably driven in a lifting direction by an arm drive means. automatic horizontal grounding command means for giving a command to horizontally ground; bucket state determining means for determining whether the angle of the bucket is at a rake angle or a dump angle than a comparative setting value in response to the command from the command means; rake correction means for causing the bucket driving means to perform rake correction operation until the correction angle setting value is reached in response to the determination result of the dump state by the determination means; A lowering/lowering rake command means for giving a lowering command to the arm driving means or a rake command to the bucket driving means together with the lowering command in response to the determination result that the lift arm is in a rake state; A loader control device comprising: a dump/sake means upon landing, which gives a dump or scoop command to the bucket drive means after reaching the ground.