JPH01296907A - Lifting control device - Google Patents

Abstract

PURPOSE:To make a tiller lower to an objected tilling depth without overshoot by making a lowering speed of a tiller in a region from a position near a field face to the objected tilling depth to decrease the more, the shallower the objected tilling depth is set. CONSTITUTION:A control means of lowering speed C controlling a decreasing ratio of lowering speed based on an objected tilling depth decided by a device of setting tilling depth 16 is provided. In a case a tiller is lowered from a level separated from field face, a lowering speed of the tiller is decreased the more, the shallower the objected tilling depth decided by a device of setting tilling depth 16, during from a time of contacting a rear cover 12a to field face till attaining the tiller at the objected tilling depth.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a lift control device, and more specifically, it lowers a tillage device supported on a vehicle body such as an agricultural tractor so as to be able to rise and fall from a position away from the field. In particular, it relates to techniques for adjusting the rate of descent.

[Conventional technology]

Conventionally, a device configured to adjust the descending speed of the tilling device as described above is disclosed in Japanese Patent Application Laid-Open No. 56-169501.
There is a control system shown in this publication, which changes the descending speed from a high-speed descending state to a low-speed descending state when the swinging rear cover provided at the rear of the tilling device touches the ground. This prevents the work efficiency from decreasing, and also suppresses the sudden increase in load when the tilling device touches the ground and the phenomenon of dashing of the vehicle body due to the driving force of the tilling device.

[Problem to be solved by the invention]

However, in the device that adjusts the descending speed as in the above reference, the speed is reduced by a preset value regardless of the value of the target plowing depth, so for example, if the target plowing depth is extremely shallow, overshoot may occur. In some cases, the tilling device descends to a level deeper than the target tilling depth and then returns to the original target tilling depth. Therefore, increasing the deceleration rate may be considered to prevent this overshoot phenomenon, but if the deceleration rate is increased too much, the tilling device may not reach the target plowing depth even if the target plowing depth is a standard value. It takes extra time to reach this point, so there is room for improvement.

The object of the present invention is to achieve the target tillage depth quickly and without overshooting, regardless of the target tillage depth, when the tillage device is lowered from a level far away from the field by rational modification. The point is to obtain a possible control device.

(Means for Solving the Problems) A feature of the present invention is that the detection result from a plowing depth sensor that measures the plowing depth of a tilling device is balanced with the target plowing depth from a manually operated plowing depth setting device. The system is equipped with an automatic tilling depth control mechanism that drives the tilling device up and down, and when lowering the tilling device from a level away from the field, the tilling device moves from a position close to the field until it reaches the target tilling depth. The method further comprises a descending speed adjusting means that reduces the descending speed to a greater extent as the target plowing depth is set to be shallower.
Its action and effects are as follows.

[For production]

If the above features are configured as shown in FIG. 1, for example, when lowering the tillage device (12) from a level away from the field (P) during work, as shown in the flowchart of FIG. From the timing when the cover (12a) comes into contact with the field (P) until the tilling device (12) reaches the target tilling depth, the shallower the target tilling depth determined by the tilling depth setting device (16), the lower the tilling device. The descending speed of (12) will be reduced to a greater extent (#4, #5, 110 steps).

In other words, by providing the descending speed adjusting means (C) that adjusts the deceleration rate of the descending speed based on the target plowing depth determined by the plowing depth setting device (16), the operator can adjust the deceleration rate each time. Therefore, the optimum descending speed can be obtained.

〔Effect of the invention〕

Therefore, by providing a lowering speed adjustment means, when lowering the tiller from a level distant from the field, the tiller can be lowered quickly and without overshoot, regardless of the target plowing depth. A control device for lowering the plowing depth at the target plowing depth was obtained.

In particular, in the present invention, if the control device is equipped with a microprocessor, it is possible to configure the descending speed adjusting means by a program, and with this configuration, it is possible to change the program without increasing the number of parts. It also has the effect of requiring only extremely simple improvements.

〔Example〕

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

As shown in Fig. 3, an engine (1) and a main clutch (2) are disposed in a connected state at the front of the vehicle body, and a transmission case (3) is disposed at the rear of the vehicle body.
Power from the front and rear wheels (4).

(5) The running system of the agricultural tractor is configured so that the information can be transmitted to each vehicle.

In this agricultural tractor, a driver's seat (7) is provided above the transmission case (3) at a position midway between the left and right rear fenders (6), and a steering handle (8) is provided in front of the driver's seat (7). A pair of left and right lift arms (10), (10) are provided on the upper part of the transmission case (3), which are raised and lowered by the operation of a hydraulic cylinder (9), and a two-point link mechanism (11) is installed on the rear surface of the transmission case (3). A rotary type tilling device (12) is provided through the tilling device (12).
By supporting the lift arms (10), (10) via the lift rods (13), (13), the level of the tilling device (12) can be adjusted by driving the lift arms (10), (10) during work. It is configured to be adjustable.

In addition, in order to control the elevation of the tillage device (12), a control box' (14) provided on the rear fender (6) is equipped with a tillage depth setting device (operated by a dial (15)) as shown in Fig. 1. The tilling device (12) is equipped with a tilling device (16), and the tilling device (12) can be adjusted from the swing angle of the rear cover (12a) during tilling.
A control box (1) is equipped with a tillage depth sensor (17) that detects the ground level of the tiller (2), and a control device (A) that raises and lowers the tiller (12) so that these signals are balanced.
4) is provided inside.

In addition, the control box (14) is equipped with a tilling device (14) that can be turned on during tilling work to give priority to automatic tilling depth control.
12) to near the upper limit and then turn it off to return to the original automatic plowing depth control.
18), and the tilling device (12) is raised and lowered by controlling the hydraulic cylinder (9) with a solenoid valve (19) operated by an output signal from the control device (A).

The control device (A) is a microprocessor (not shown)
In addition, an automatic tillage depth control mechanism (B) for performing automatic tillage depth control operations is set in a programmed state, and a tillage device (12 ), the tilling device (12) is lowered at high speed until it reaches the level shown in Figure 3, and after reaching this level, the lowering speed is adjusted to reduce the descending speed according to the target tilling depth. The adjusting means (C) is also set in the programmed state.

Figure 2 shows the tilling device (12) during automatic tilling depth control.
This figure shows the flow of control when raising and lowering the vehicle by operating the forced raise switch (18).

In other words, when the forced lift switch (18) is turned on during automatic plowing depth control (steps #1 and #2), the lift arm (10) is driven to the upper limit (step #3), and then the plowing depth setting device ( Deceleration parameters are calculated based on the signal from 16) (steps #4 and #5).

This deceleration parameter is a numerical value for giving a target descending speed when reducing the descending speed of the tilling device (12), and the value is determined so that the shallower the target plowing depth, the greater the reduction in the descending speed.

Next, when the forced lift switch (18) is operated OFF (#6 step), the solenoid valve (19) is operated fully open to drive the lift arm (10) in the downward direction (1
1? step).

Then, as shown in Fig. 3, the tilling device (12) continues to descend until the rear cover (12a) touches the ground (steps #8 and #9), and after the point when the rear cover (12a) is detected to touch the ground, The solenoid valve (19) is operated intermittently to lower the tiller (12) at the set speed according to the deceleration parameter determined in step 110), the tiller (12) is
12) reaches the target plowing depth (#11, 111)
Step 2), automatic plowing depth control is started (Step #13).

In this embodiment, steps #4, #5, and #10 are collectively referred to as a descending speed adjusting means (C), and the step 1113 is referred to as an automatic plowing depth control mechanism (B).

[Another example]

In addition to the embodiments described above, the present invention includes, for example, a descending speed adjusting means,
The control system can be implemented in various ways, such as configuring the automatic plowing depth control mechanism with a hard circuit consisting of a combination of logic gates, comparators, etc. Also, if the target plowing depth is relatively shallow,
The operation of the descending speed adjusting means may be set so that the descending motion is stopped for a short time when the tilling device reaches a predetermined level.

Furthermore, in the embodiment described above, the timing of reducing the descending speed was made to coincide with the timing of detecting the grounding of the rear cover, but the deceleration may be reduced by reducing the descending speed at the timing when the tilling device has descended to a predetermined position at the vehicle body level. The timing can also vary.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the elevation control device according to the present invention, and the first embodiment
2 is a block circuit diagram of the control system, FIG. 2 is a flowchart showing the operation of the control device, and FIG. 3 is an overall side view of the tiller in a lowered state. (12)... Cultivation device, (16)...
Tilling depth setting device, (17)...... tilling depth sensor, (B)
. . . Automatic plowing depth control mechanism, (C) . . . Lowering speed adjustment means, (P) . . . Field scene.

Claims (1)

[Claims] A tilling depth sensor (17) that measures the tilling depth of the tilling device (12).
) and the manually operated plowing depth setting device (16
) is provided with an automatic tillage depth control mechanism (B) that drives the tillage device (12) up and down so as to balance the target tillage depth from the field (P).
), the tillage device (12) is lowered into the field (P
) A lifting control device comprising a descending speed adjusting means (C) that reduces the descending speed in the region from a position near the point until reaching the target plowing depth to a greater extent as the target plowing depth is set to be shallower.