JPH053A - Lifting control device for work equipment - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a work device that can always drive a work device at a constant ascending / descending speed, enhance running safety, and reduce the possibility of lowering work efficiency, and perform comfortable work. . A work device is connected to the traveling machine body so as to be driven up and down by a hydraulic actuator 3, and pressure oil from a hydraulic pump 7 driven by an engine 6 is supplied to the hydraulic actuator 3 to output an output speed of the engine 6. Based on the detection result of the rotation speed detecting means 8 for detecting the speed, the ascending / descending speed control means B for adjusting and controlling the ascending / descending speed of the working device 2 by adjusting and controlling the amount of pressure oil supplied to the hydraulic actuator 3 so as to match the control target value. And an ascending / descending speed detecting means PM for detecting an actual ascending / descending speed of the working device, and an ascending / descending speed detecting means P.
Based on the detection result of M, the control target correction means C for correcting the control target value by the ascending / descending speed control means B is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention connects a working device to a traveling machine body by a hydraulic actuator so that the working device can be moved up and down, and supplies pressure oil from a hydraulic pump driven by an engine to the hydraulic actuator. A rotation speed detecting means for detecting the output rotation speed of the engine, and adjusting and controlling the pressure oil supply amount to the hydraulic actuator to match the control target value based on the detection result of the rotation speed detecting means. A lifting control device for a working machine, comprising: a lifting speed control means for adjusting and controlling the lifting speed of the device.

[0002]

2. Description of the Related Art In the lifting control apparatus for a working machine described above, a hydraulic cylinder is conventionally used as the hydraulic actuator, and an electromagnetic proportional flow control valve is provided in a pressure oil supply passage for the hydraulic cylinder to provide the engine. The opening of the electromagnetic proportional flow control valve is changed and adjusted so that the control flow rate is uniformly determined according to the preset characteristic based on the detection result of the rotation speed detection means.

[0003]

In the above conventional structure, since the hydraulic pump is driven by the engine, even if the opening of the electromagnetic proportional flow control valve interposed in the hydraulic circuit is constant, the engine speed is increased. Is different, the discharge amount from the hydraulic pump changes and the pressure oil supply amount to the hydraulic actuator is different.Therefore, this should be corrected to prevent the pressure oil supply amount from changing. It was done. However, in the above-mentioned conventional structure, since the characteristic of the opening degree of the electromagnetic proportional flow control valve with respect to the engine speed is uniformly determined, for example, the individual difference in the characteristic of the electromagnetic proportional flow control valve, the hydraulic pressure, etc. There may be a case where the preset control value for the electromagnetic proportional flow rate control valve is not suitable due to individual differences in the overall characteristics of the circuit system or differences in the hydraulic oil temperature. In such a case, the lifting speed of the work device cannot be kept constant, and if the lifting speed is too fast, the safety of traveling work in the field is lacking, and if it is too slow, there are drawbacks such as a decrease in work efficiency. there were. The present invention aims to eliminate the above-mentioned problems.

[0004]

According to a characteristic configuration of the present invention, in a lifting control device for a working machine described at the beginning, a lifting speed detecting means for detecting an actual lifting speed of the working device,
The control target correction means for correcting the control target value by the lift speed control means based on the detection result of the lift speed detection means.

[0005]

Based on the detection result of the engine speed, the hydraulic actuator is drive-controlled so as to match the control target value preset corresponding to the detected rotation speed, regardless of the change in the engine speed. The lifting speed of the work device is controlled to be maintained at a preset speed. At this time, the actual lifting speed of the working device is detected, and when the actual lifting speed is different from the value set above, the control target value is corrected to always drive the working device at an appropriate lifting speed. It can be carried out.

[0006]

Therefore, it is possible to suppress the characteristic variation due to the individual difference of the hydraulic devices of the individual working machines, and to always move the working apparatus up and down at a constant ascending / descending speed, thereby improving the safety of work traveling. In addition to being able to work, there is no fear of lowering work efficiency and comfortable work can be performed.

[0007]

Embodiments will be described below with reference to the drawings. Figure 3
Fig. 1 shows a riding type rice transplanter as an example of a working machine. This rice transplanter is constructed by connecting a seedling planting device 2 via a link mechanism 1 to a rear portion of a riding type traveling body so as to be driven up and down by a hydraulic cylinder 3 [an example of a hydraulic actuator]. Potentiometer-type grounding sensor 4R that detects the height against the mud surface while following the grounding on the left and right sides of the seedling planting device 2.
4L, the hydraulic cylinder 3 is controlled so that the average value of the detection values of the ground sensors 4R, 4L matches a preset predetermined value, and the height of the seedling planting device 2 against mud surface during planting work is controlled. The automatic raising / lowering control means A for maintaining a constant level is provided, and the operating lever 5 for raising / lowering the seedling planting device 2 is provided in the machine control section. When the operating lever 5 is operated to the “planting position”, the automatic raising / lowering operation is performed. When the control means A is operated and is operated to the "raised position", the seedling planting device 2 is operated to be lifted to the maximum raised position, and when the "raised position" is switched to the "descended position", the seedling planting device 2 is operated. Is configured to descend from the maximum rising position to the mud surface grounding position.

Then, when the seedling planting device 2 is raised from the grounded position to the maximum raised position and is lowered from the maximum raised position to the grounded position, the pressure oil for the hydraulic cylinder 3 is determined based on the rotation speed of the engine 6. It is configured to change and adjust the supply amount. More specifically, as shown in FIG. 1, a hydraulic system is configured to supply hydraulic oil to the hydraulic cylinder 3 from a hydraulic pump 7 driven by an engine 6, and a hydraulic system is provided in the hydraulic oil supply passage. An electromagnetic proportional flow rate control valve V capable of changing the supply pressure oil flow rate is provided by changing and controlling the duty ratio of the supplied pulse current. A rotation speed detection sensor 8 [an example of rotation speed detection means] for detecting the output rotation speed of the engine 6 is provided near the engine 6.
In addition, the link mechanism 1 is attached to the body side connection portion of the link mechanism 1.
A potentiometer PM (an example of the ascending / descending speed detecting means) for detecting the swing angle of the is provided.

A control device 9 for supplying a control current to the electromagnetic proportional flow rate control valve V is provided, and the control device 9 executes the above-mentioned automatic raising / lowering control during the planting work so that the seedlings are planted. The pressure oil supply amount to the hydraulic cylinder 3 is controlled based on the detection result of the rotation speed detection sensor 8 when the auxiliary device 2 rises from the ground contact position to the maximum lift position and when it descends from the maximum lift position to the ground contact position. Ascending / descending speed control means B for adjusting and controlling the ascending / descending speed of the seedling planting device 2 so as to match the target value, and the ascending / descending speed based on the ascending / descending speed of the seedling planting device 2 detected by the potentiometer PM. The control target correcting means C for correcting the control target value of the control means B is provided in the form of a control program. That is, the control device 9 executes the control as follows.

As shown in FIG. 2, the operating lever 5 is
If there is no raising or lowering operation and it is set to the “planting position” or the “lowering position”, each of the ground sensors 4
Read the detection values of R and 4L (steps S1 to S3),
The electromagnetic proportional flow rate control valve V, that is, the hydraulic cylinder 3 is controlled and driven so that the average value of these detected values matches a preset reference value (step S4). Then, when the operation lever 5 is moved from the “down position” to the “up position” or vice versa, the detection value Ne of the rotation speed detection sensor 8 is read (step S5) and preset. Based on the characteristic, the duty ratio E of the pulse current of the ascending / descending drive current is calculated, the flow control valve V is driven by the duty ratio E, and the seedling planting device 2 is driven up or down (steps S6 and S7). ). Next, this seedling planting device 2
The output of the potentiometer PM by the operation of is read and the actual ascending / descending speed is calculated (steps S8, S
9). If the calculation result is within the predetermined setting range, the state is maintained as it is. If it exceeds the setting range, the characteristic of the pulse duty ratio of the up-and-down drive current with respect to the output of the rotation speed detection sensor 8 in step S6 is The drive current is corrected to the smaller side, and if it is below the set range, the above characteristics are corrected to the side where the drive current is increased (step S10,
S11, S12). The characteristics thus corrected are stored in the non-volatile memory 10 (steps S13 and S1).
4). Then, in the next ascending / descending speed control, the control is executed based on the characteristics thus stored. The step S3 constitutes the automatic lifting control means A, the step S7 constitutes the lifting speed control means B, and the step S3
The control target correction means C is constituted by 11 and S12.

It should be noted that reference numerals are added to the claims for facilitating the comparison with the drawings, but the present invention is not limited to the configuration of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 Control block diagram

[Fig. 2] Control flowchart

[Figure 3] Overall side view of rice transplanter

[Explanation of symbols]

 2 Working device 3 Hydraulic actuator 6 Engine 7 Hydraulic pump 8 Rotation speed detection means B Up / down speed control means C Control target correction means PM Up / down speed detection means

Claims (1)

Claim: What is claimed is: 1. A working device (2) is connected to a traveling machine body by a hydraulic actuator (3) so as to be movable up and down, and is driven by an engine (6) with respect to the hydraulic actuator (3). And a rotation speed detecting means (8) for detecting the output rotation speed of the engine (6) and a detection result of the rotation speed detecting means (8). And an ascending / descending speed control means (B) for adjusting and controlling the ascending / descending speed of the working device (2) by adjusting and controlling the amount of pressure oil supplied to the hydraulic actuator (3) so as to match the control target value. A lifting / lowering control device for a working machine, wherein the lifting / lowering speed detection means (PM) for detecting an actual lifting / lowering speed of the working device (2), and the lifting / lowering movement based on a detection result of the lifting / lowering speed detection means (PM). Speed control Stage (B) control target correcting means for correcting the control target value by (C) a working machine lifting control device that is equipped with.