JPS6119404A - Front and rear direction posture control apparatus of earth working machine - 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 This invention relates to a longitudinal attitude control device for automatically controlling the longitudinal attitude of a ground-based working machine to maintain a constant position even when the plowing depth varies.

Conventional technology A ground work machine is connected to a towing machine by lower links on the left and right sides and a short top link at the upper center, and as it rises, the upper part tilts more forward due to the influence of the top link. When working in areas with deep plowing depths, the vertical position of the ground implement increases as it moves up and down, making it difficult to drive the plowing nail. The sliding angle and the angle when separating from the tilled soil change, and the sliding contact angle of the trailing edge of the rear cover that makes sliding contact with the tilled soil surface also changes, resulting in changes in the reversal effect, soil splash distance, excavation depth, etc. Since the leveling effect also changes as the ground work machine moves up and down, there is a problem that a constant effect cannot be obtained.

Problems to be Solved by the Invention The present invention attempts to prevent fluctuations and decreases in the plowing effect and leveling effect when the plowing depth changes by controlling the longitudinal attitude of the ground working machine.

Technical means for solving the problems In order to solve the above problems, the present invention has taken the following technical means.

Means for solving the problem, namely, a ground-based work machine that is connected to the traction machine (1) through a three-point linkage mechanism () and raised and lowered by a hydraulic lifting mechanism (8). In order to maintain a predetermined posture, the top link (6) of the three-point linkage mechanism (7) is configured to be controlled to expand and contract according to the vertical position of the ground work machine (2).

Embodiment and operation Next, one embodiment of the present invention will be explained based on the drawings. 1st
As shown in the figure, a rotary tilling device as an example of a ground working device (2) is attached to the rear of a tractor as a towing machine (13) to a pair of left and right lift arms (3), (a), and a left and right lift rod is attached to the rear of the tractor. (Connected by a three-point link mechanism (7) consisting of left and right lower links (5) 15 that swing up and down through 4λ (4) and a top link (6) at the upper center,
This three-point linkage mechanism (7) is connected to its lift arm (3-
(3) is lifted and lowered by a hydraulic lifting mechanism (8) which uses hydraulic pressure to move up and down using a lift cylinder. The top link (6) is formed to be extendable and retractable by a top link cylinder (9) and a piston (9a), and is connected to an oil pump (Iυ) by the operation of an electromagnetic switching valve (11).
By controlling the supply and discharge of pressure oil to the top link cylinder (9), the ground work machine (2) can operate the lower link (
5) The rear connecting bin (to) of (5) will be used as a fulcrum overnight using the front and rear tilt sensor (Sρ, front and rear tilt setter (D), vertical position sensor (S), top link length sensor (S3)
Based on the output of the control device aa consisting of a microcomputer, which performs the control based on the detected values and set values of
The drive circuit for expansion aL, the drive circuit for reduction 11,
It is something that is done by working.

That is, a longitudinal tilt sensor (Sl) that transmits the longitudinal swing of the pendulum to the detection shaft of a rotary potentiometer is attached to the traction machine (1), and the detection shaft of the rotary potentiometer is connected to the lift arm (3). ) is installed on the lift shaft that rotates with the lift arm (3) to detect the vertical position of the lift arm (3), and the detection shaft of the linear sliding potentiometer is fixed to the piston (9a) to connect the top link. (9
The top link length sensor (S,) detects the length of is input to the multiplexer of the control device aa, and inputted to the longitudinal inclination setting device (I) t-multiplexer αIK consisting of something like a rotary potentiometer. The longitudinal inclination setting device (I) is manually operated, and the detected value and set value of the tow are converted into digital values by the A/D converter ae, and the control computer αη detects the longitudinal inclination of the traction machine (1). The longitudinal inclination setting value of the longitudinal inclination setter (I) is corrected according to the value, and the relative longitudinal inclination setting value that should be maintained for the ground work machine (2) with respect to the towing machine (1) is determined. 2) current lifting position detection value (lift arm (3) in the example)
When the ground work machine (2) is at the lift arm angle with respect to the horizontal plane), the ground work machine (2) is set at the above-mentioned relative longitudinal inclination setting value (in the example, the ground work machine with respect to the vertical plane (the longitudinal inclination angle (θ) that should be maintained in η)) Top link length uA to hold n
The expansion and contraction of the top link (6) is controlled until the top link length detected by the top link length detector (S) matches the calculated top link length t. . Then, the top link length 4) for holding the ground work machine (2) at various longitudinal inclination angles (θ) at each of the vertical and vertical inclination angles (θ) can be determined geometrically. The control device a memorizes the diagram in Fig. 3 and calculates the current slope (7), the toe arm angle (2), the longitudinal inclination angle ( The top link length 4) as a control amount is calculated based on θ). In addition, as an example, the longitudinal posture of the ground work machine (2) is controlled so that it is slightly tilted backward as the lifting position becomes lower, so that ground work can be carried out even if the plowing depth becomes large. The angle of the universal joint shaft (2) connecting the input shaft that drives the working part of the machine (2) and the PTO shaft (1) of the traction machine (1) (PTO shaft (2),
The intersecting angle between the input shaft a9 and the universal joint shaft clp is reduced, the rotational noise of the universal joint shaft a+9 is reduced, and power transmission is performed smoothly. Although not shown, the ground work machine (2) detects the front-back attitude of the powder by the front-back inclination sensor attached to K, and adjusts the front-back inclination setting by the front-back attitude setting device (D). In order to match the detected value of the longitudinal inclination by the longitudinal inclination sensor,
The above-mentioned control device may be configured, and in this case, the control becomes simple, but each time the ground work machine (2) is replaced, the installation of the longitudinal inclination sensor must be replaced.
In contrast, in the illustrated example, such a number of steps are unnecessary.

In addition, the lifting position can be detected using the operating lever of the hydraulic lifting mechanism aυ.
It is also possible to use a potentiometer to detect the operating angle of the lever 4 and the movement distance of a link, for example, of the elevating and lowering operation mechanism linked to the elevating and lowering operation lever 4.

Effects of the Invention This invention provides a three-point link, 4*411(7) as described above.
A hydraulic lifting mechanism (8) is connected to the traction machine (1) via a
), the three-point linkage mechanism (7
) is configured to expand and contract according to the elevation position of the ground work equipment (2), so for example, if the towing equipment (1) moves up and down or tilts back and forth. Even if the ground work equipment (2) goes up and down due to such reasons, the ground work collector (2) maintains a predetermined longitudinal attitude, so the sliding contact angle of the trailing edge of the rear cover that makes sliding contact with the slanted upper surface remains constant. At the same time, the driving angle of the plowing nails and the angle of separation from the plowed soil do not change, so there is no change in the reversal of the fruit, the distance of the plowed soil, the excavation depth, or the leveling effect.
The desired tillage effect can always be obtained.

[Brief explanation of the drawing]

The figure shows one embodiment of this invention, and FIG. 1 is an overall side view;
FIG. 2 is a block diagram of the control device, and FIG. 3 is a control characteristic diagram. Code explanation

Claims (1)

[Claims] The top link of the three-point linkage mechanism is connected to the towing machine via the three-point linkage mechanism so that the ground work equipment is raised and lowered by the hydraulic lifting mechanism, and the front and back posture of the ground work equipment is maintained at a predetermined position. 1. A longitudinal attitude control device for a ground-based work machine, characterized in that it is configured to perform expansion and contraction control according to the vertical position of the ground-based work machine.