JPH01168202A - Control structure for rotary tiller - Google Patents

Abstract

PURPOSE:To prevent a rotary tiller from lifting to the upper limit even if a plowing depth setter is set to a shallower side than the corresponding plowing depth level in controlling in a state of a hoisted back cover, by adding a memorizing means and a control target changing means to a control structure. CONSTITUTION:A control structure is additionally provided with a memorizing means (M) for holding the maximum rocking posture on the lower side of a back cover in lifting or lowering based on a signal from a sensor 18 and a control target changing means (D) for discriminating a state of a set target rocking posture when the target rocking posture is set on the lower side from the maximum rocking posture held by the above-mentioned memorizing means and changing the target rocking posture on a slight upward side from the maximum rocking posture.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a plowing depth setting device for setting a target swinging posture of the rear cover, a sensor for detecting the swinging posture of the rear cover, and a detection signal from the sensor. The present invention relates to a control structure for a rotary tiller comprising control means for controlling the lifting actuators to a state corresponding to a signal from a tilling depth setting device.

[Conventional technology]

Conventionally, there is a control structure configured as described above, such as the one shown in Japanese Patent Application Laid-Open No. 169501/1982. Used for work, etc.

[Problem that the invention seeks to solve]

Now, when considering puddling work in paddy fields, the level of the rotary tilling device is often set by so-called position control, which maintains the level of the rotary tilling device at a predetermined value relative to the vehicle body. The rear cover may be held up while being swung upwards.

In other words, because rice fields contain a lot of water and are soft, it may be difficult to accurately follow the field with a rear cover of a normal shape that is manufactured for use in upland fields. In some cases, the rear cover was held up while swinging upward.

In addition, the lift control of the rotary tillage device is so-called automatic, which operates based on the control target determined by the tillage depth setting device and the feedbank signal from the sensor that detects the rocking posture of the rear cover. There are plowing depth control and position control mentioned above, and there are two ways to operate these two types of control.
There are two possible methods: one that simultaneously operates the control of species and gives priority to the one with a higher level of control target, and the other that artificially selects one of the controls. If the former control is performed with the rear cover lifted as described above, the following operations may occur.

In other words, when performing plowing work with the rear cover lifted, the control target level for position control is set to a relatively high level, so the control target level for automatic tillage depth control determined by the tillage depth setting device is set to a relatively high level. It can be in any position as long as it is lower than the control target level. However, the control target level of automatic tilling depth control is near the tilling depth level corresponding to the swinging posture of the lifted rear cover, and on the side shallower than this tilling depth level (the side where the rear cover is about to droop). is set, for example, in order to deepen the plowing depth, if the control target level of position control is significantly lowered and set to a lower level than the control target of automatic plowing depth control, due to the priority relationship described above, When the automatic plowing depth control starts, the swinging of the rear cover is restricted, so a feedback signal to stop the rotary tiller from rising cannot be obtained, and the rotary tiller will rise to its upper limit. .

In addition, this phenomenon occurs when the rear cover is lifted to perform platform work and only its downward swinging is restricted, and when the rear cover is lowered to the side deeper than the plowing depth level corresponding to the rocking posture regulated by the lifting During automatic plowing depth control by setting a control target level on the side where the plow is lifted,
For example, it may occur when the tilling depth setting device is operated for the purpose of shallowing the tilling depth, and in this case as well, as mentioned above,
The rotary tiller was supposed to be raised to the upper limit because a feedback signal on the lifting stop side could not be obtained due to the rocking restriction of the rear cover.

An object of the present invention is to provide rotary tilling even if the tilling depth setter is set to a shallower side than the tilling depth level corresponding to the lifting level of the rear cover during control with the rear cover lifted, through reasonable modification. The point is to configure a control structure that does not allow the device to rise to its upper limit.

[Means for solving problems]

The present invention is characterized in that, in the control structure of the snow raising structure, a storage means for storing the maximum swinging posture of the lower side of the rear cover during lifting and lowering based on a signal from the sensor; If the target swinging posture is set below the maximum swinging posture, determine this state, and
The control target changing means is provided for changing the target swinging attitude slightly above the maximum swinging attitude, and its functions and effects are as follows.

[For production]

If the above characteristics are configured as shown in FIGS. 1 and 4, and the operation is set as shown in the flowcharts of FIGS. 2 and 3, the rear cover (13) is lifted and moved downward. After this, the cover (
If the control target is set to a shallower side than the plowing depth level corresponding to the hanging posture of item 13), the hanging level of the rear cover (13) is determined based on the value of the signal in the storage means (M). When the plowing depth setter (20) is set to a shallower side than the plowing depth corresponding to this lifting level, the control target changing means (D) determines this state, and the storage means (M). Based on the signal value, the control target is slightly changed toward the shallow side (the side that lifts the rear cover upward), so the rotary tiller (R) starts to descend and the rear cover (13) is raised. When the target attitude is reached by touching the ground, it becomes possible to output a signal to stop the control.

〔Effect of the invention〕

Therefore, by modifying the storage means and the control target changing means to the extent that the rear cover is lifted, the tilling depth setting device is set to a shallower side than the tilling depth corresponding to the lifting level of the rear cover during control when the rear cover is lifted. Even when the rotary tiller is raised, the tilling depth is maintained at a level that substantially corresponds to the lifting level of the rear cover, so a control structure has been constructed in which the rotary tiller does not rise to the upper limit.

In particular, in the present invention, since both the storage means and the control target changing means can be configured in the form of a program, in a control system equipped with a microprocessor, the present invention can be easily modified by simply changing the program. It can be effective.

〔Example〕

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

Figure 5 shows a rotary tiller (R) connected to the rear end of the vehicle body of an agricultural tractor so that it can be driven up and down. A hydraulic cylinder (2) (an example of an actuator (A)) and a pair of left and right lift arms (3) that swing up and down by the operation of the hydraulic cylinder (2) are provided, and a driver's seat (4) is provided. ) is located on the right side of the dial (5) for setting the tilling depth of the rotary tiller (R).
a control box (6) with a control box (6), and an operating lever (
7) is located.

As shown in the figure, the rotary tilling device (R) is connected to the rear end of the vehicle body via a link mechanism (8), and a lift is connected between the rotary tilling device (R) and the lift arm (3). By installing the rod (9), the hydraulic cylinder (
The rotary tillage device (R) is configured to be driven up and down by the operation of 2), and this rotary tillage device (R) has a number of tillage types (10) that are driven and rotated by the power transmitted from the vehicle body. The upper cover (11) to prevent this upper cover (
11) The rear cover (13) is connected to the rear end so as to be swingable around the horizontal support shaft (12), and in order to apply a biasing force to the rear cover (13), the rear frame (14) and the rear cover ( 13), and upper and lower coil springs (15) supported by this rod (15).
16) and (17) respectively, and during work, the rotary tilling device (
A potentiometer-type cover sensor (18) for detecting the plowing depth of the rotary tiller (R) is provided on the upper surface of the upper cover (11), and similarly detects the plowing depth of the rotary tiller (R) from the swinging posture of the lift arm (3). A potentiometer-type lift arm sensor (19) that detects the vehicle body level is connected to the lift arm (
3) is provided at the proximal end.

In this agricultural tractor, the lifting and lowering of the rotary tillage device (R) is controlled by a control system having the configuration shown in FIG. 20), the cover sensor (18), a position setting device (21) operated by the operation lever (7),
A control device (to which signals from the lift arm sensor (19), these setting devices, and sensors are input, and which operates a solenoid valve (22) for the hydraulic cylinder (2);
C), and this control device (C) has an input interface (23), a microprocessor (24), a memory (25) (an example of storage means (M)), and an output interface (26), respectively. Furthermore, the operation of this control device (C) is controlled by a position setting device (21) and a lift arm sensor (19) as shown in the flowchart of FIG.
) position control based on signals from the plowing depth setting device (
20) and automatic plowing depth control based on the signal from the cover sensor (18), which are automatically selected and performed, and the plowing operation shown in FIG. 5, etc. During automatic tilling depth control when the rear cover (13) is lifted so as not to come into contact with the tilling surface (P), a third step is set so that the lifting and lowering control of the mouth-kuri tilling device (R) does not become impossible. The operations are set as shown in the flowcharts of FIGS. 2 and 3.

That is, as shown in FIG. 2, when the control is started, the signal value (Fc) from the cover sensor (18) is first inputted.
Me) and the signal value (FC) are compared (#b step), and the signal value (FC) is in a lower level state (rear cover (
13) represents the hanging side) (step #c), rewrite the signal value on the memory (25) to (Fc), and call the rewritten value (MC) (step #d). ).

The operations in steps #a to #d above are processes for determining and storing the maximum swinging posture of the lower side of the rear cover (13), and are used as a reference for operations during automatic plowing depth control, which will be described later. used.

Next, input the signal value (SP) of the position setter (21) and the signal value (So) of the plowing depth setter (20) (#e step), and check that the respective signal values (SP) and (So) are From the indicated levels, the control on the setting device side that is set higher is selected (#f step).

When position control is selected, the signal value (PL) from the lift arm sensor (19) is input (#g step), and feedback operation is performed based on the signal values (SP) and (PL) (#g step). h step), and when automatic plowing depth control is selected, input the signal value (F,) from the cover sensor (18) #i step, and feedback based on the signal value (so), (pc) The operation is started (#j step).

In addition, the j step is expressed as shown in Fig. 3, and in this step, the signal value (pc) and the signal value (25) on the memory (25) are
MC) and #1 step), the signal value (F,) is at a lower level (the side where the rear cover (13) hangs down)
(#2 step), the tillage depth setting device (
Instead of the signal value (SO) from 20), a value (Me + α) at a level slightly deeper than the signal value (MC) (on the side where the rear cover (13) is lifted) is set as the control target (#3 step), If this condition does not apply, use the plowing depth setting device (20).
The signal value (SO) from is set as the control target (#4 step).

The operations in steps #1 to #3 above are performed, for example, when the rear cover (13) is lifted up as shown in FIG. It functions during automatic tilling depth control when the tilling depth setting device (20) is set to stop the lifting operation when the rear cover (13) swings, and the control target is set within the swing range of the rear cover (13). This is to stop the rising operation by changing to .

Next, when the control target is determined as described above, this control target is compared with the signal value (sn) to calculate the position deviation (step #5), and if this position deviation is within the dead band, If the position deviation is outside the dead band and within the intermittent operation range, the lift operation is performed in the intermittent operation mode.
If it is outside the intermittent operation range, it will perform lifting and lowering operations in continuous operation mode (Steps #6, #7, #8, and #9).
.

Incidentally, the intermittent operation mode is a mode in which the solenoid valve (22) is operated with an intermittent signal to raise and lower the rotary tiller (R) at a slow speed, and the continuous operation mode is a mode in which the solenoid valve (22) is operated with an intermittent signal. In this mode, the rotary tiller (R) is rapidly raised and lowered by operating the rotary tiller (R) using a DC signal.

Further, the basic configuration of the present invention is configured as shown in the block diagram of FIG. 1, the control target changing means (D) consists of steps #1 to #3 in the flowchart of FIG. 3, and the control means (E)
consists of steps #5 to #9, the storage means (M) consists of the memory (25) as mentioned above, and the actuator (A) consists of the hydraulic cylinder (2) as mentioned above.

In addition, when hanging the rear cover (13), use the rondo (1
The engagement position of the beta pin (27) that engages with the upper part of the rond (15) is lowered so that the upper spring (16) acts, and the stopper (28) that engages with the lower part of the rondo (15) is set to a lower position.
) to lower the engagement position and set the lower spring (17) to a non-acting state.

[Another example]

In addition to the above-mentioned embodiments, the present invention also provides, for example, a control means, a storage means, and a control target changing means, each of which is a logic gate, a comparator,
It is also possible to configure it in hardware by combining latch circuits and the like, and even if it is configured in software, the flow of control can be freely set.

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 control structure of the rotary tillage device according to the present invention, FIG. 1 is a claim correspondence diagram showing an overview of the control structure, FIG. 2 is a flowchart showing the elevation control operation, and FIG. A flowchart showing the deep side JMm operation, FIG. 4 is a block circuit diagram of the control structure, and FIG. 5 is a side view of the rear part of the agricultural tractor during plowing work. (13)... Rear cover, (18)...
Sensor, (20)...Plowing depth setting device, (A)...
... Actuator, (D) ... Control target changing means, (E) ... Control means, (M) ...
...Memory means.

Claims (1)

[Claims] A tilling depth setting device (20) that sets the target swinging posture of the rear cover (13), a sensor (18) that detects the swinging posture of the rear cover (13), and a detection signal from the sensor (18) sets the tilling depth. This is a control structure for a rotary tiller comprising control means (E) for controlling an actuator (A) for raising and lowering to a state corresponding to a signal from a rear cover (13) during raising and lowering. ) storage means (M) for holding the maximum rocking posture on the lower side based on the signal from the sensor (18); A rotary rotary rotary machine comprising control target changing means (D) for determining the state when a target swinging attitude is set and changing the target swinging attitude slightly above the maximum swinging attitude. Control structure of tillage equipment.