JPH01300808A - Rise and fall control device of movable agricultural working machine - Google Patents

Abstract

PURPOSE:To make a rising amount of a working device approximately equal to a dropping amount of the working device, by shortening ON time of output pulse during dropping in comparison with ON time during rising. CONSTITUTION:ON time of output pulse to control rise and fall of a working device 1 based on a vehicle 3 is controlled in such a way that ON time during dropping is made shorter than ON time during rising and the working device 1 is raised or dropped. A rising amount of the working device 1 is made approximately equal to a dropping amount. When rise and fall of the working device l is controlled in given height from the ground, following response at the rise side and the fall side to the given height is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a lifting control device for a mobile agricultural machine, and can be used to control lifting and lowering of a combine harvester's reaping device, a tractor's tilling device, and the like.

Conventional technology Conventional 1 For example, a reaping device attached to the front part of a combine adjusts the cutting height during reaping work depending on the planting state of the culms and the hardness and softness of the soil surface on which the machine runs. For this reason, a height sensor is installed to detect the height of the reaping device above the ground, and the reaping device is raised and lowered based on the detection results of this height sensor, so that the cutting height can be adjusted to a predetermined height. Elevation control is performed to maintain the position.

Problems that the invention aims to solve However, the field conditions where the harvesting work was carried out were poor.

When the vehicle body moves up and down as the vehicle travels, the reaping device moves up and down and the height above the ground changes, so the reaping device is controlled to rise and fall so as to maintain this height above the ground at a predetermined height. However, the lifting device that raises and lowers the reaping device relative to the vehicle body is
Many types use a hydraulic cylinder to lower the harvesting device using its own weight, so if the ON time of the output pulse that activates this hydraulic cylinder is the same, the speed on the descending side is 1 degree faster than on the ascending side. Since the amount of descent is larger than the amount of rise, it is necessary to control the lifting and lowering of mobile agricultural implements that require delicate position adjustments such as cutting height control, so that the height of the working equipment can be adjusted to the same level. The purpose is to smooth the height tracking response.

Means for Solving the Problems This invention is based on the detection of the height sensor (2) that detects the height of the work equipment W (1), so that the work equipment (]) is moved relative to the vehicle body (3). O when the output pulse rises to control the elevation
A lifting control device for a mobile agricultural machine is configured so that ON time during descent is controlled to be shorter than N time.

Effect of the Invention While the height of the work device (1) above the ground is detected by the height sensor (2), the work device (1) is adjusted based on the height above the ground detection result of the height sensor (2). Work is carried out by controlling the vehicle body (3) to move up and down and maintaining it at a predetermined height above the ground. The ON time of the output pulse for raising and lowering the working device (1) with respect to the vehicle body (3) is controlled so that the ON time during descending is shorter than the ON time during ascending. 1) is raised and lowered.

Effects of the Invention In this way, since the ON time (Tl) of the output pulse is controlled to be shorter than the ON time (T1) during the descent, the amount of rise and fall of one working device (1) can be reduced. can be made almost the same.

Therefore, when controlling the working device (1) to raise or lower to a predetermined height above the ground based on the detection result of the height sensor (2), the follow-up response on the rising side and the descending side to this predetermined height above the ground This improves the performance and allows for smooth ascending and descending control.

The rotating example shows a combine harvester equipped with a lifting control device according to the present invention, in which a threshing device +51 is mounted on a car body (3) having left and right running devices (4), and a husk is installed in the front part. A working device (1) for reaping is provided so as to be able to be raised and lowered with respect to the vehicle body (3) by expanding and contracting an elevating cylinder (6).

The lifting cylinder (6) that raises and lowers the working device (1) relative to the vehicle body +3) is expanded and contracted by hydraulic pressure, and a lifting solenoid valve is used to supply and discharge pressure oil from a hydraulic pump to this lifting cylinder (6). (7) and a downward solenoid valve (8), which are configured to be electromagnetically switched. A lifting lever (9) is provided to raise and lower the working device (1) by switching the raising solenoid valve (7) or the lowering solenoid valve (8).

The height above the ground is measured by measuring the length of time it takes for the working device (1) to reach the height above the ground at the rear of the cutting blade device (I).

FIG. 2 is a block diagram showing the control, in which the detection information of the height sensor (2) is input to the control device 0υ having a CPU, input/output devices, etc. ). (121 is a pulse generation circuit, and based on the output signal from the control device 01), the ON time (T1) of the output pulse output to the ascending valve (7) is transmitted to the descending solenoid valve (8). The configuration is such that the ON time (T2) of the output pulse is controlled to be shortened.

A is a switch for controlling the cutting height.

The height above the ground is measured by the height sensor (2) when multiple detection values by the height sensor (2) are input to the control device 0υ, the average value of these is calculated, and this average value is The working device (1) is initially controlled to move up and down so that the cutting height is maintained within a set range.

A working device that transmits power to each part and uses the lifting lever (9)! +1+ is lowered to a predetermined cutting height position. Run the combine harvester and turn on the cutting height control switch (11).
Then, the height sensor (2) measures the height of the working device (1) from the ground multiple times, and the average value is determined by the control device! (lO
The reference cutting height is calculated by calculating the following.

During mowing, the height above the ground is detected by the height sensor (2), and the average value of a predetermined number of times is sequentially compared with the previous average value, and the mowing height is raised to within a predetermined range. Solenoid valve (7) or down solenoid valve (8)
), an output pulse signal is output to the solenoid to extend and retract the lifting cylinder (6), and the working device (1) is moved up and down to control the cutting height.

In contrast to the ON time (T1) of the output pulse output to the ascending solenoid valve (7), the ON time (T2) of the output pulse output to the descending solenoid valve (8)
Because it is controlled to be short.

The lifting amount of the work device (1) can be made almost the same, and lifting control can be performed smoothly.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a side view of the front part of the combine, Fig. 2 is a block diagram showing control, and Fig. 3 is an explanatory diagram of output pulses. In the figure, code (1) is the working device, (2) is the height sensor, (
3) shows the vehicle body, and (11) shows the control device.

Claims (1)

[Claims] The ON time when the output pulse rises to control the lifting and lowering of the working equipment (1) relative to the vehicle body (3) based on the detection of the height sensor (2) that detects the height of the working equipment (1). This is an elevation control device for a mobile agricultural machine which controls the ON time during descent to be shortened.