JP2508745B2 - Cultivator lift control device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cultivator lift control device for an agricultural working machine in which a power farming machine is equipped with a cultivator.

[Prior Art] When lowering the cultivator from the lifting position to the working position,
There is an elevating control device configured to decrease the descending speed at the time of grounding to avoid an impact. Conventionally, the timing for lowering the descending speed has been set to be constant, or the operator has arbitrarily set the timing.

[Problems to be Solved by the Invention] However, if the timing of lowering the descending speed is constant, the desired descending speed control can be achieved when the tire diameter of the power farm machine is changed or when the mounting posture of the cultivator is changed. There was a problem that it could not be done. Further, if the operator arbitrarily sets the lowering position for lowering the descending speed depending on the situation in the field, there is a problem that the operator's burden is heavy and it is difficult to take appropriate measures.

[Means for Solving Problems] In order to solve the above problems, the present invention has the following configuration.

That is, the cultivator lift control device for an agricultural work machine according to the present invention is a lift control device for an agricultural work machine that controls the cultivating depth of the cultivator based on the rotational displacement amount of the rear cover of the cultivator. Memorize the ground surface height of the field calculated from the relative height of the tiller and the set value of the tilling depth, and when the tiller descends from the hoisting position to the working position, the ground surface height remembered during the previous work is reached. The feature is that it is configured to reduce the descending speed of the tiller immediately before.

[Operation] When lowering the cultivator from the hoisting position to the working position when not in operation, the descending speed can be automatically reduced immediately before the ground surface height stored during the previous work.

[Embodiment] FIG. 1 is a view showing a usage state of an embodiment of an agricultural working machine (1) according to the present invention, in which a roller cultivator 5 is attached to a link device 3 provided at a rear portion of a power agricultural machine (tractor) 2. It is installed.

The rotary cultivator 5 has a transmission case 10 provided at the center of the upper part.
A chain case 11 and side plates (not shown) are attached to the ends of the pipes protruding from both sides of the pipe, and a plurality of plowing blades 13 are planted around the bottoms of the chain case 11 and the side plates. The cultivating shaft 14 is rotatably supported. The cultivating shaft 14 is covered with a rotary cover 15 including an upper cover 15a, side covers 15b and 15b, and a rear cover 15c. The upper cover 15a and the side covers 15b, 15b are fixed to the machine body, while the rear cover 15c is rotatably attached to the rear end of the upper cover 15a by a hinge. The rear cover 15c is provided with a rear cover sensor 16 for detecting the rotational displacement amount (rear cover angle) of the cover. Further, one mast 17 is provided on the upper part of the machine body as a connecting device to the tractor 2.

The link device 3 includes one top link 20 and a pair of left and right lower links 21, 21, and the top link 20 is a cultivator 5.
The mast 17 and the lower links 21, 21 are attached to the side portions of the transmission case 10 of the cultivator 5, respectively. The lower links 21 and 21 have lift rods 26,
It is suspended by a hydraulic lift arm 27 of the tractor 2 by 26.

The tractor 2 is provided with an electro-hydraulic working machine lifting device having proportional solenoid valves 30 and 31 for raising and lowering, and the lift arm 27 is rotated up and down by the hydraulic pressure of the lifting device. ing. At the side of the cockpit 33, a position lever 34 for raising and lowering the tiller within a range between a working position and a non-working position (lifting position), a tiller depth setting device 35 for setting the tiller depth of the tiller at the time of working. Etc. are provided. A sensor arm 37a connected to the lower link 21 by a sensor rod 37a is arranged in parallel with the lift arm 27, and a lift arm angle sensor 37 for detecting the angle of the lift arm 27 is provided at the base of the sensor arm. Has been.

An elevating control device 39 for controlling the elevating device is constructed as shown in FIG. That is, the position commanding signal for raising and lowering the tiller by the position lever 34 and the lift arm angle sensor 37
And the detection signal of the rear cover sensor 16 and the working depth setting device 35
The setting signal of the working depth by is supplied to the CPU 41 through the A / D converter 40, and by processing these signals, the opening / closing signal is output to the rising valve 30 and the descending valve 31. The operation of the lifting control device 39 will be described below with reference to the flowchart shown in FIG.

A dead zone which is a permissible range with a predetermined upper and lower width is set for the working depth setting value, and the lift arm 27 is set from the working depth setting value and the rear cover sensor value so that the actual working depth falls within this dead zone during work. Is determined. The lift arm 27 operates according to the above determination when the previous control is neutral and when the previous and present times are both moving up and down.
Also, when the previous control was in the ascending / descending operation, when the neutral decision is made in this control, that is, when the dead zone is entered, the lift arm angle at that time is obtained and this is successively averaged. By updating the average value, calculate the ground surface height of the field from this lift arm angle average value and plowing depth setting value,
Remember that value. When the work is interrupted by turning or the like, the cultivator 5 is raised to the non-working position by the position lever 34.

When the tiller 5 is lowered to the work position after the turning, the descending speed is determined from the ground surface height of the field and the lift arm angle calculated during the work in the previous stroke. However, when starting the first work, a preset fixed value is used as the ground surface height. As shown in FIG. 4, the descending speed starts to decrease from a position slightly above the ground surface, reaches a minimum at the time of contact with the ground, and then increases to the target depth (cultivation depth). Generally, since tilling work is performed while making a U-turn of an agricultural work machine at the end of the field to reciprocate in the field, the one stroke and the next stroke are adjacent to each other, and the ground surface heights of both are almost equal. I can think. Therefore, if the descending speed is controlled on the basis of the average ground surface height of the previous stroke, appropriate control can be obtained according to actual conditions. It descends at high speed just before touchdown, becomes slow at touchdown, and speeds up again after touchdown, so that the cultivator can be quickly lowered, and recoil and impact at touchdown can be reduced.

EFFECTS OF THE INVENTION As is clear from the above description, the lifting control device according to the present invention stores the ground surface height at the time of the previous work, and when the working machine that has been temporarily lifted is lowered again, Since the descending speed control is automatically performed so that the minimum speed is achieved at the time of contact with the ground, an optimal descending condition can be obtained even if the operator does not perform the descending speed control operation each time. It should be noted that a preferable descending speed can be obtained by changing the tire diameter of the power farming machine or changing the mounting posture of the cultivator.

[Brief description of drawings]

FIG. 1 is a side view of an agricultural working machine to which the present invention is applied, FIG. 2 is a block diagram of a lifting control device, FIG. 3 is a control flow chart, FIG. 4 is an explanatory view showing a descending speed change, and FIG. It is an explanatory view showing an example of control. 1 ... tractor, 3 ... link device, 5 ... rotary cultivator, 15c ... rear cover, 16 ... rear cover sensor, 2
7 …… Lift arm, 29 …… Lift control device, 30,31 …… Proportional solenoid valve, 34 …… Position lever, 35 ……
Plowing depth setting device, 37 ... Lift arm angle sensor.

Claims (1)

(57) [Claims] 1. A lifting control device for an agricultural work machine, which controls the working depth of a tiller based on a rotational displacement amount of a rear cover of the tiller, and a relative height of the tiller and a working depth set value with respect to a power farm machine during normal work. The height of the ground surface of the field that is calculated from is stored, and when lowering the cultivator from the hoisting position to the working position, the descending speed of the cultivator should be reduced immediately before reaching the ground surface height memorized during the previous work. A tiller lifting control device characterized by being configured as.