JP2637650B2 - Work vehicle attitude control structure for ground work - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground work device attitude control structure for a work vehicle in which a ground work device is connected to a rear portion or a front portion of an airframe so as to be able to change its attitude.

[0002]

2. Description of the Related Art In a riding type rice transplanter which is an example of a work vehicle as described above, a seedling planting device (corresponding to a ground working device) is moved up and down by a hydraulic cylinder (corresponding to an actuator) at the rear of the machine. (Corresponds to a posture change operation). A height sensor (corresponding to a posture sensor) for detecting the height from the rice field to the seedling planting device is provided, and the seedling planting device is maintained at the set height from the rice field based on the detection of the height sensor. Lift control means (corresponding to attitude control means) for raising and lowering the seedling planting apparatus by a hydraulic cylinder
It has. In this case, a sensitivity lever (corresponding to sensitivity setting means) that can artificially change the control sensitivity of the elevation control means on the sensitive side and the insensitive side is provided, and the operator operates the sensitivity lever according to the state of the rice field. Operate to set the control sensitivity. Generally, if the mud on the rice paddy is hard, the control sensitivity is set to the insensitive side, and if the mud is soft, the control sensitivity is set to the sensitive side so that the so-called hunting phenomenon in which the seedling planting apparatus moves up and down in a short cycle is not caused. So that the seedling planting device can be smoothly moved up and down.

[0003]

However, the mud hardness of all parts in one paddy field is not constant, and the mud hardness varies in each part of the paddy field in many cases. Therefore, even if the initially set control sensitivity is appropriate, the hardness of the mud changes with the progress of the planting operation, and the set control sensitivity may not be appropriate. In such a state, the hunting phenomenon occurs in the seedling planting apparatus, so the operator must operate the sensitivity lever to change the control sensitivity to an appropriate one, but like a riding rice transplanter. When the seedling planting device is connected to the rear part of the machine body, the operator may not notice that the seedling planting device has caused a hunting phenomenon. In some cases, the operator may not be able to determine whether the seedling-planting apparatus actually causes the hunting phenomenon by visual inspection alone. SUMMARY OF THE INVENTION It is an object of the present invention to accurately determine whether or not a hunting phenomenon has occurred in a ground working device, and to perform a corrective action when a hunting phenomenon has occurred.

[0004]

The feature of the present invention resides in the following configuration of the work vehicle ground control device attitude control structure described above. That is, an artificial operation type sensitivity setting means capable of arbitrarily setting and changing the control sensitivity of the attitude control means, and a position sensor for detecting the position of the ground work device with respect to the aircraft, the control sensitivity set by the sensitivity setting means. If the vertical movement of the ground work equipment in a short cycle below the setting continues for a set number of times or more in a state of, the sensitivity adjustment means for automatically changing the control sensitivity within a set range including the set control sensitivity. When the vertical movement of the ground working device stops at the control sensitivity changed by the sensitivity adjusting means, the sensitivity maintaining means for maintaining the control sensitivity, and the control sensitivity changed by the sensitivity adjusting means. If the vertical movement of the ground working device does not stop, a notifying means for notifying the worker of this state is provided.

[0005]

With the above construction, the operator first checks the state of the ground before starting the work, predicts the appropriate control sensitivity, and operates the sensitivity setting means to set the control sensitivity. Then, after the setting of the control sensitivity is completed, the attitude control of the ground working device is started. When the attitude control is performed with the control sensitivity described above, the position of the ground working device with respect to the aircraft, that is, the vertical movement of the ground working device, is detected by the position sensor. Then, when the ground working device moves up and down in a short cycle equal to or shorter than the setting, it is determined that the ground working device has started to hunt, instead of moving up and down by a normal attitude control operation. Therefore, the number of vertical movements in a short cycle equal to or less than the setting is equal to the set number (the total number of vertical movements within the set time,
Otherwise, the number of vertical movements in the case of continuous vertical movement, etc.) does not continue, and it is determined that the control sensitivity initially set is appropriate and the ground work equipment has not caused a hunting phenomenon, and the control sensitivity is determined. The attitude control is continued. Conversely, if the number of vertical movements is equal to or greater than the set number, it is determined that the initially set control sensitivity is not appropriate and a hunting phenomenon has occurred. In this case, the control sensitivity is slightly changed to the insensitive side or the sensitive side, and the attitude control is performed with the changed control sensitivity. In this state, if the vertical movement (hunting phenomenon) of the ground working device stops, the attitude control is continued with the changed control sensitivity. As described above, if the operation of changing the control sensitivity does not eliminate the vertical movement (hunting phenomenon) of the ground working device, even if the control sensitivity is slightly changed near the initially set control sensitivity, the operation of the ground It is determined that the vertical movement (hunting phenomenon) of the device cannot be suppressed. As a result, the notification means operates to notify the operator of this state.
The operator confirms the ground condition again by this notification, and operates the sensitivity changing means to greatly change the control sensitivity so as to obtain the control sensitivity suitable for the ground condition.

As described above, the position sensor detects whether or not the ground working device has moved up and down to cause a hunting phenomenon mechanically and electrically. The presence or absence of the hunting phenomenon can be accurately determined. Since the operator is notified by the notification means when the hunting phenomenon is detected, the operator does not notice that the hunting phenomenon has occurred and does not leave the hunting phenomenon.

When notifying the operator of the occurrence of the hunting phenomenon, the operator is not notified immediately when the hunting phenomenon is detected. Instead, the control sensitivity is slightly changed before the notification, and the hunting is performed with the changed control sensitivity. Determine if the phenomenon disappears. If the hunting phenomenon disappears after the control sensitivity is slightly changed in this way, the attitude control may be performed while maintaining the changed control sensitivity, so that the operator's hand is not bothered. Conversely, if the hunting phenomenon does not disappear, the initially set control sensitivity is far from the ground condition, so in such a case, notify the worker and operate the sensitivity change means. Then, the control sensitivity is changed to an appropriate one.

[0008]

As described above, the presence or absence of the hunting phenomenon is accurately detected mechanically and electrically by the position sensor and is notified so as to be easily understood by the operator, thereby preventing the hunting phenomenon from being left unattended. It was possible to prevent the failure of ground work due to the neglect of the phenomenon (such as poor planting of seedlings). Then, when notifying the worker of the occurrence of the hunting phenomenon, the control sensitivity is changed in advance to test whether the hunting phenomenon disappears.If the hunting phenomenon disappears by this operation, the operator may be troubled. Therefore, the operability for the worker is also good.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a seedling planting device 3 (corresponding to a ground working device) is provided at the rear of the body supported by the front wheel 1 and the rear wheel 2.
Are connected via a link mechanism 4 to form a riding type rice transplanter which is an example of a work vehicle. A hydraulic cylinder 5 (corresponding to an actuator) provided at the rear of the machine body and a link mechanism 4 are connected via a suspension spring 21, and the hydraulic cylinder 5 allows the seedling planting device 3 to freely move up and down. ing.

As shown in FIG. 1, the seedling planting apparatus 3 includes a planting case 7 having a pair of planting arms 6 and driven to rotate, a seedling rest 8 driven to reciprocate laterally left and right, and a seedling plant. A grounding float 15 for partially supporting the load of the attachment device 3 and leveling is provided. A sled-shaped ground sensor 11 (corresponding to a posture sensor) that follows the ground on the rice field G (corresponding to the ground) is supported so as to be vertically swingable around a front fulcrum. A potentiometer 12 for detecting the angle of the sensor 11 as the height from the rice field surface G to the seedling planting apparatus 3 is provided.

Next, the operation of the elevation control means (corresponding to the attitude control means) for automatically and artificially raising and lowering the seedling planting apparatus 3 will be described. As shown in FIG. 2, a planting lever 13 is provided in the control unit. When the planting lever 13 is operated to an ascending position, a descending position, and a neutral position, a control device 18 is provided.
Thereby, the control valve 20 for the hydraulic cylinder 5 is operated, and the artificial raising and lowering operation of the seedling planting apparatus 3 can be performed. During this time, the planting operation of the seedling planting apparatus 3 is stopped.

On the other hand, during planting when the planting lever 13 is operated to the planting position, the ground contact sensor 11
Follow the ground. The control valve 20 is operated by the control device 18 so that the signal from the potentiometer 12 of the grounding sensor 11 enters the dead zone X1 across the set value, as shown in FIG. 3 is automatically moved up and down. As a result, the seedling planting apparatus 3 is automatically maintained at the set height from the rice field surface G.

In this case, the width of the dead zone X1 shown in FIG. 4 becomes the control sensitivity of the elevation control. The control sensitivity becomes sensitive if the width of the dead zone X1 is narrow, and the control sensitivity becomes wide if the width of the dead zone X1 is wide. Becomes insensitive. Then, as shown in FIG. 2, by operating a sensitivity lever 9 (corresponding to a sensitivity setting means of an artificial operation type) provided on a control section of the aircraft, the width (control sensitivity) of the dead zone X1 is arbitrarily changed and set. it can.

Next, the raising and lowering control of the seedling planting apparatus 3 during the planting run, in which the planting lever 13 is operated to the planting position and running, will be described with reference to FIGS. Before starting the planting run, the operator determines the state of the paddy field (hard and soft of mud) and operates the sensitivity lever 9 of FIG. 2 so that the control sensitivity is considered appropriate by the operator (step S1). Then, it is assumed that the control sensitivity thus set is a dead zone X1 as shown in FIG.

As shown in FIG. 1, a potentiometer 19 (corresponding to a position sensor) for detecting the vertical position of the planting apparatus 3 with respect to the machine body is provided at the base of the link mechanism 4. When the planting travel is started, the elevation control of the seedling planting apparatus 3 is immediately started by the elevation control means. From the stop state, the planting travel is started and the set time elapses. The value detected by the potentiometer 19 at the position where the control valve 20 is stabilized at the neutral position (the position at which the signal from the potentiometer 12 of the ground sensor 11 enters the dead zone X1 across the set value as shown in FIG. 4) It is stored as a reference voltage T (step S2).

After continuing the elevating control, it is assumed that the seedling planting device 3 starts to move up and down with respect to the machine body. In this case, the vertical movement of the seedling planting device 3 is detected by the potentiometer 19 in FIG.
8 are sequentially input. As shown in FIG.
Of the detection voltage T1 that changes between high and low across the reference voltage T, the change in the detection voltage T1 that does not exceed the set voltage width a across the reference voltage T (the seedling plant 3
), This single change is counted.

Thereafter, the count of the change in the small detection voltage T1 is accumulated within the set time (steps S3, S4, S5, S6). Then, after the elapse of the set time, if the total number of small changes in the detection voltage T1 is less than the set number of times NT (step S7), it is determined that the first control sensitivity set in step S1 is appropriate. Then, the operation returns to step S3 without performing any special operation, and the counting of the small change in the detection voltage T1 is restarted.

Conversely, if the total number of small changes in the detection voltage T1 is equal to or greater than the set number of times NT (step S7), it is determined that the initial control sensitivity set in step S1 is not appropriate and a hunting phenomenon has occurred. Is determined. In this case, as shown in FIG. 4, the control sensitivity is changed from the dead zone X1 to the dead zone Y1 (step S8) (corresponding to the sensitivity adjusting means). Then, the lift control is continued for a set time in the dead zone Y1, and during this time, the small detection voltage T1 is detected.
(Steps S9, S10, S1)
1, S12).

As described above, the control sensitivity is changed to the dead zone Y1.
If the total number of small changes in the detection voltage T1 is less than the set number of times NT (step S13), it is determined that the control sensitivity (dead zone Y1) is appropriate and the hunting phenomenon has disappeared. Thereafter, the elevation control is performed with the control sensitivity of the dead zone Y1 (step S14) (corresponding to sensitivity maintaining means).

Conversely, if the total number of small changes in the detection voltage T1 exceeds the set number of times NT even when the control sensitivity is changed to the dead zone Y1 (step S13), the control sensitivity (dead zone Y1) is not appropriate and hunting occurs. It is determined that the phenomenon has not disappeared, and the process returns from step 15 to step S8 to change the control sensitivity to the dead zone Y2 as shown in FIG. As described above, a small change in the detection voltage T1 is counted. If the total number of the changes is less than the set number of times NT, the process proceeds to step S14, where the elevation control is performed with the control sensitivity of the dead zone Y2. .

As described above, even if the control sensitivity is changed from the dead zone Y1 to the dead zone Y6 as shown in FIG.
If the total number of changes exceeds the set number of times NT (step 1
3, S15), it is determined that the hunting phenomenon cannot be suppressed with the control sensitivity near the dead zone X1. As a result, the alarm lamp 10 (corresponding to the notifying means) shown in FIGS. 1 and 2 blinks, and the alarm buzzer 14 (corresponding to the notifying means) sounds to notify the worker of this state (step 16). The operator confirms the state of the rice field G again by this warning, and operates the sensitivity lever 9 to largely change the control sensitivity so as to obtain a control sensitivity suitable for the state of the rice field G. .

[Alternative Embodiment] In the above embodiment, the seedling planting device 3 is connected to the hydraulic cylinder 5 via the suspension spring 21. However, the seedling planting device 3 is used without using the suspension spring 21. It may be of a type directly connected to the hydraulic cylinder 5. In this case, the grounding float 15 shown in FIG. 1 is not generally provided, and the expansion and contraction of the hydraulic cylinder 5 causes the seedling planting apparatus 3 to move up and down as it is. Also, instead of raising and lowering control means for automatically raising and lowering the seedling planting apparatus 3, the inclination of the seedling planting apparatus 3 with respect to the rice field G is detected, and the seedling planting apparatus 3 is set to be parallel to the rice field G. Thus, the present invention can be applied to a rolling control unit that performs a rolling operation on the seedling planting device 3. The present invention is not only a riding type rice transplanter, but also a riding type direct sowing machine in which a direct sowing machine (corresponding to a working device) is connected to the rear of the machine so as to be able to move up and down, and an agricultural tractor in which a rotary plow is connected to the rear of the machine so as to be able to move up and down. Also, the present invention can be applied to a riding lawn mower or the like in which a mower is connected to the front part of the fuselage so as to be movable up and down.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is an overall side view of a riding rice transplanter.

FIG. 2 is a circuit diagram showing a relationship among a sensitivity lever, a planting lever, a hydraulic cylinder, a control valve, and the like.

FIG. 3 is a diagram showing a state of a signal from a potentiometer for detecting a vertical position of the seedling placement apparatus with respect to the airframe.

FIG. 4 is a diagram showing a dead zone for a signal from a potentiometer of a ground sensor.

FIG. 5 is a flowchart showing the first half of a control flow;

FIG. 6 is a flowchart showing the latter half of the control flow.

[Explanation of symbols]

 Reference Signs List 3 Ground work equipment 5 Actuator 9 Sensitivity setting means 10, 14 Notification means 11 Attitude sensor 19 Position sensor NT Number of times set G G Ground

Claims (1)

(57) [Claims] An actuator (5) for changing the attitude of a ground working device (3) connected to an airframe, and an attitude sensor (11) for detecting the attitude of the ground working device (3) with respect to the ground (G). Posture control means for operating the actuator (5) so that the ground working device (3) maintains a predetermined posture with respect to the ground (G) based on a detection value of the posture sensor (11). An attitude control structure for a ground working device of a working vehicle, comprising: an artificial operation type sensitivity setting means (9) capable of arbitrarily setting and changing the control sensitivity of the attitude control means; and the ground working device (3) for an airframe. Position sensor (1
9), in the state of the control sensitivity set by the sensitivity setting means (9), the vertical movement of the ground work apparatus (3) in a short cycle equal to or less than the setting continues for a set number of times (NT) or more. And sensitivity adjustment means for automatically changing the control sensitivity within a set range including the set control sensitivity, and the ground working device (3) with the control sensitivity changed by the sensitivity adjustment means. If the vertical movement of the ground work device (3) is not eliminated by the sensitivity maintaining means for maintaining the control sensitivity and the control sensitivity changed by the sensitivity adjusting means if the vertical movement of the ground work apparatus is not eliminated, An attitude control structure of a work vehicle with respect to a ground, comprising a notifying means (10) and (14) for notifying a worker of a state.