JPS63202306A - Compaction apparatus of seeder for paper pot - 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 relates to a position control device for a working vehicle such as an agricultural tractor.

[Prior art and problems to be solved by the invention] Generally, in this type of work vehicle, the elevation control of the attached work equipment is performed in accordance with the lever operation of the position control lever. In some cases, the working part is raised and lowered at a constant speed by feedback control to perform stable raising and lowering control. However, feedback control is based on detecting the operating speed of one working part and determining whether or not this is the set operating speed, so that the operating speed remains constant. At the beginning, it was designed to emit a constant pulse or a slightly larger pulse, which not only requires a special detection sensor, but also has the drawback of inevitably causing a shock at the beginning of operation. Moreover, when the weight of the working part is changed, if the operating speed of the working part changes and there is no predetermined detection at the beginning of operation, there will be a delay until the detection necessary to perform feedback control properly. This poses a problem because it has the drawback of causing a delay in operation.

[Means for Solving the Problems] In view of the above-mentioned circumstances, the present invention was created with the aim of providing a position control device for a work vehicle that can eliminate these drawbacks. , the position control mechanism that controls the elevation of the working part following the lever operation of the position control lever is activated from an inching control mode that controls the operating speed to gradually increase when the working part begins to move up and down in response to the lever operation. The present invention is characterized in that a mode switching means is provided which is set to switch to a feedback control mode in which the speed is controlled to be constant.

According to the present invention, with this configuration, the shock at the start of operation is reduced, and position control can be performed without delay in operation even if the weight of the working part changes.

[Example] Next, an embodiment of the present invention will be explained based on the drawings. In the drawing, 1 is a traveling body of an agricultural tractor, and behind the traveling body 1 is a rotary tilling type working section 2. is attached by a lifting link mechanism 3. The working part 2 is moved up and down by vertical swinging of a lift arm 5 extending from the hydraulic case 4. Further, a position control lever 8 is provided on one side of a fender 7 that covers the left and right rear wheels 6, and a control section 9 configured using a microcomputer is arranged near the position control lever 8.

On the other hand, 10 is a lever angle detection sensor that detects the lever operation angle of the position control lever 8, and 11 is an arm angle detection sensor that detects the swing angle of the lift arm 5, and the detection values from these sensors 10 and 11 are is input to the control section 9. The control unit 9, which has received these detected values, issues control commands to the lifting solenoids 12 and 13, which will be described later, to control the position of the working unit 2.

Next, the procedure of this position control will be explained using a flow chart and a timing chart. Here, the detection value of the lever angle detection sensor 10 is the lever detection value A, and the detection value of the arm angle detection sensor 11 is the arm detection value B.
For convenience, it is written as .

First, turn on the key switch and start.

Arm detection value B is larger than lever detection value A (B>A
), that is, it is determined whether the working part 2 is at a higher position than the lever set position. If the judgment is made that the lever detection value A is too large, it is necessary to perform control to lower the working part 2, and conversely, if the judgment is made that the lever detection value A is too small, the lever detection value A must be controlled to lower the working part 2. It is determined whether the detected value is larger than B (A>B), and if it is determined that the window is larger, it is necessary to control the working part 2 to raise it, and if it is not larger, it is determined that the window is If the judgment is made, both detection values A and B are equal, and in this case, an ear command is issued to the solenoid 12.13, and the working part 2
is maintained at the relevant posture height. It goes without saying that the detection values A and B are equal within a certain dead zone in order to perform stable control.

In this way, when the lever detection value A and the arm detection value B are different, it is necessary to control the elevation and descent of the working part 2, which is accomplished as follows. Here, the ascending control is the same as the descending control, so to explain the descending control in detail, as mentioned above, when it is determined that the arm detection value B is greater than the lever detection value A, then the lever detection value A is It is possible to determine whether the value obtained by adding the preset value α is larger than the arm detection value B, that is, whether the working part 2 is within the range of the set value α with respect to the lever set position. If it is determined that the position is at a high position beyond the range of the set value α, the position mode ■ (position mode ■ in the case of ascending control) is set, and the continuous l A command based on the mode is issued to the descending solenoid 13, and the working part 2 descends at high speed. On the other hand, if the old judgment is made that the working part 2 is within the range of the set value α, it is determined whether the previous mode was the position mode ■, that is, the working part 2 is lowered to the set value α while descending at high speed. A judgment is made as to whether or not it is within the range, and if an arbitrary judgment is made that it is, the position mode ■' (position mode ■' in the case of upward control) is set, and the duty ratio of the ON time is set. initially large t
The deceleration mode gradually decreases from ti and then becomes constant at a small t2 degree, and the working part 2 descends from the high-speed descending state in a decelerated state. O here
The mode having a duty ratio of N time t2° is set so that the working part can be raised and lowered even when the weight of the working part becomes heavy or the oil temperature rises. Furthermore, if a negative judgment is made that the previous mode is not position mode ■, position mode ■ (position mode ■ in the case of upward control) is set. In this position mode ■, the duty ratio of the opening time is initially small. Then, after an appropriate period of time (after three pulses in the embodiment), the feedback control mode is entered and the working part 2 descends at a constant speed. In this case, the opening time is t, (or t
The mode with the duty ratio i) can operate at low speed when the weight of one working part is light, and the ON time t, (
Alternatively, ti) is set to a mode in which the working part is raised and lowered even when the working part is heavy or the oil temperature rises. In this way, the mode switching means is formed.

Here, feedback control is performed by the following procedure. In other words, in the feedback control mode, it is first determined whether or not there has been a change in the arm detection value B, and if it is determined that there has been a change, then it is determined whether or not the counter is operating, and the counter is activated. If the old judgment is made that it is inside, time is measured from the counter data, and it is judged whether the rate of change of the lift arm 5 is appropriate. If it is determined that it is appropriate, the duty ratio of 0N-Off is maintained as it is. On the other hand, if the park determines that it is not appropriate, it is determined whether the speed of change of the lift arm 5 is too fast, and if the park determines that the speed of change is too fast, the duty ratio of the opening time is changed. control to make it smaller,
On the other hand, if a negative judgment is made that it is too slow, the duty ratio of the ON time is controlled to be large, thereby attempting to maintain the operating speed of the lift arm 5 constant.

In an embodiment of the invention constructed as described.

The working part 2 is moved up and down by lever operation of the position control lever 8.
If the lever is operated rapidly and greatly, the height of the working part will be located at a position that exceeds the range of the set value α relative to the lever position, and as a result, high-speed work in position mode ■ or continuous mode This means that the vertical elevation control will be performed. When the working part 3 reaches the set value α, this is determined and control is performed using the position mode ■' or the gradually decelerating inching mode of ■', and the working part 3 is positioned at the lever set position. . As a result, while the working part 2 can be quickly controlled up and down, the operation can be performed without shock at the beginning and end of the operation.

On the other hand, when the position control lever 8 is operated slowly and in small steps, it is determined that the working part height does not deviate from the range of the set value α, and based on this, the position mode
Or, elevation control will be performed following the lever operation in (■), but at the beginning of operation, this control is in inching control mode in which the duty ratio of the ON time gradually increases, before entering feedback control mode. After that, control is performed in a feedback control mode in which the operating speed is constant. As a result, at the beginning of the operation, before reaching the feedback control, the working part 2 begins to move up and down at low speed, and then enters a feedback control state in which the operating speed is constant, and smooth lifting and lowering operation without shock is achieved. It happens. Moreover, since the working part starts operating at a low speed before starting feedback control at the beginning of operation, it is possible to count this and perform feedback control using this as data.
Therefore, even if the weight of the working part increases or the oil temperature increases, feedback control without delay in operation can be performed, and position control can be performed quickly and reliably.

In addition, this device includes a lever angle detection sensor 10 and an arm angle detection sensor 11 that detect changes in the operation of the working part 2 as the position control lever 8 is operated.
Based on the detected value, it can be carried out appropriately according to the situation.

Since a general detection sensor can be used, the detection means can be made more versatile, which can greatly contribute to the simplification of the structure and cost reduction.

[Operations and Effects] In summary, since the present invention is configured as described above, the position of the working part is controlled in accordance with the lever operation, and feedback control can be carried out to keep the lifting operation speed constant. However, at the beginning of operation, it is in inching control mode, which is the stage before feedback control.

The working part starts lifting and lowering at a low speed, so that the shock at the beginning of the operation is significantly reduced and smooth lifting and lowering can be achieved. What's more, with this product, the counter reading required for feedback control is performed in advance from the stage of lifting and lowering in 1-inch control mode, and this can be used as data for feedback control, which increases the weight of the working part and increases the oil temperature. Even in cases where the operation is slow due to other reasons, delay in operation can be avoided and position control can be performed quickly and reliably.

[Brief explanation of the drawing]

The drawings show an embodiment of the position control device for a work vehicle according to the present invention, in which FIG. 1 is an overall side view of an agricultural tractor, FIG. 2 is a block circuit diagram of the control mechanism, and FIG. 4 is a timing chart, FIG. 5 is a timing chart of each mode, FIG. 6 is a flowchart of feedback control, and FIG. 7 is a timing chart thereof. In the figure, 1 is a traveling body, 2 is a working part, 8 is a position control lever, and 9 is a control part.

Claims (1)

[Claims] The position control mechanism controls the lifting and lowering of the working part in accordance with the lever operation of the position control lever, and the inching control mode controls the operating speed to gradually increase when the working part begins to move up and down in response to the lever operation. 1. A position control device for a work vehicle, comprising mode switching means configured to switch to a feedback control mode in which the operating speed is controlled to be constant.