JP4944712B2 - Work vehicle attitude change structure for work vehicles - Google Patents

Description

  The present invention relates to a working device posture changing structure for a work vehicle that includes an actuator that changes the posture of a working device connected to a machine body, and has posture control means that actuates the actuator so that the working device is maintained at a target posture. .

  In a riding type rice transplanter that is an example of a work vehicle, for example, as disclosed in Patent Document 1, a seedling planting device (corresponding to a work device) (4 in FIG. 1 of Patent Document 1) is moved up and down at the rear of the machine body. A hydraulic cylinder (corresponding to an actuator) (2 in FIG. 1 and FIG. 2 of Patent Document 1) that is connected freely and drives the seedling planting device up and down is provided. A grounding float (corresponding to a grounding body) (15 in FIG. 1 and FIG. 2 of Patent Document 1) that follows the ground surface (corresponding to the work site) is provided in the seedling planting device so as to be raised and lowered. ) To a seedling planting device (equivalent to posture detection means) (39 in FIG. 2 of Patent Document 1).

  As a result, the hydraulic cylinder operates at a higher speed as the detected value of the height sensor deviates from the target value. Based on the deviation between the detected value of the height sensor and the target value, the detected value of the height sensor becomes the target value. The seedling planting device is driven up and down by a hydraulic cylinder so as to be a value. When the detection value of the height sensor becomes the target value, the seedling planting device is maintained at the set height from the rice field, and the seedling planting depth by the seedling planting device is maintained at the set depth. (Equivalent to attitude control means).

JP 2003-92903 A

In Patent Document 1, since the seedling planting device is driven up and down by the hydraulic cylinder based on the deviation between the detected value of the height sensor and the target value, a deviation between the detected value of the height sensor and the target value has occurred. Later, the hydraulic cylinder operates (the hydraulic cylinder does not operate unless a deviation between the detected value of the height sensor and the target value occurs).
Thereby, for example, when the wheel of the aircraft rides on the convex part or falls into the concave part, the seedling planting device rapidly rises or falls (when the detection value of the height sensor deviates rapidly from the target value), Since the hydraulic cylinder will operate after this, even if the hydraulic cylinder operates at a high speed, the seedling planting device is maintained at the set height from the rice field at the initial point when the seedling planting device is rapidly raised or lowered. The seedling planting depth by the seedling planting device may not be maintained at the set depth.

  The present invention relates to a work device posture change structure for a work vehicle that includes an actuator that changes a posture of a work device connected to a machine body, and a posture control unit that operates the actuator so that the work device is maintained at a target posture. When the posture of the working device changes rapidly, the object is to reduce (shorten) the state where the working device is not maintained in the target posture as much as possible.

[I]
(Constitution)
The first feature of the present invention resides in the following configuration in the working device attitude changing structure of a work vehicle.
An actuator is provided for changing the attitude of the work device connected to the machine body. A posture detecting means for detecting the posture of the working device and a change speed detecting means for detecting a changing speed of the posture change of the working device. The higher the detection value of the posture detection means deviates from the target posture, the faster the actuator is operated based on the first control gain. The higher the detection value of the change speed detection means, the higher the speed of the actuator based on the second control gain. A posture control means is provided that is actuated to maintain the work device in a target posture by an actuator. Control gain changing means capable of changing the second control gain is provided.

(Function)
According to the first aspect of the present invention, the apparatus includes posture detecting means for detecting the posture of the working device and change speed detecting means for detecting the changing speed of the posture change of the working device.
For example, when the work device rapidly deviates from the target posture, before the deviation between the detection value of the posture detection means and the target posture occurs (the dead zone is generally set in the target posture, the detection value of the posture detection means It takes a little time until the deviation occurs from the target posture (dead zone), and the change speed detecting means detects the change speed of the posture change of the work device (the change speed of the change posture of the work device is Because of a sudden change), before the deviation between the detection value of the posture detection means and the target posture occurs, the actuator starts to operate according to the detection value of the change speed detection means.

Thus, according to the first feature of the present invention, the actuator starts operating at an earlier point in time than the configuration in which the actuator is operated only by the deviation between the detected value of the posture detecting means and the target posture, and the work device is moved to the target posture. Therefore, it is possible to reduce (shorten) the state in which the working device is not maintained in the target posture at an initial time when the working device rapidly deviates from the target posture.
In this case, the higher the detection value of the change speed detection means becomes (the more the change speed of the posture change of the working device changes suddenly), the actuator operates at a higher speed and tries to return the working device to the target posture. The state in which the working device is not maintained in the target posture at the initial time point when the head rapidly deviates from the target posture can be further reduced (shortened).

Each time the change rate of the change in posture of the work device is detected (every time the change rate of the change in posture of the work device changes), the state of the work place is determined when the actuator starts to operate according to the detection value of the change speed detection means. Depending on the work mode, the posture of the work device may be frequently changed, and the posture of the work device may be unstable.
According to the first aspect of the present invention, the control gain changing means capable of changing the second control gain is provided. As a result, when the second control gain is changed to the small side, when the actuator starts to operate according to the detection value of the change speed detection means as described above, the change in the attitude of the work device is changed for the detection value of the change speed detection means. Therefore, the actuator can be set to operate at a low speed, and it is possible to avoid a situation in which the posture of the working device is not stabilized due to the actuator operating at a high speed.

  Conversely, it is necessary to further reduce (shorten) the state in which the work device is not maintained in the target posture at the initial point when the work device rapidly deviates from the target posture, depending on the state of the work place and the work form. In this case, by setting the second control gain to the large side, the actuator is set to operate at a high speed for the detection value of the change speed detection means (for the change speed of the posture change of the working device). Therefore, the state in which the working device is not maintained in the target posture at the initial time when the working device rapidly deviates from the target posture can be further reduced (shortened).

(The invention's effect)
According to the first aspect of the present invention, the work of the work vehicle is provided with an actuator that changes the posture of the work device connected to the airframe, and has posture control means that operates the actuator so that the work device is maintained at the target posture. In the device posture change structure, by configuring the actuator to operate according to the posture of the work device and the change speed of the posture change of the work device, the state where the work device is not maintained at the target posture is reduced (shortened). As a result, the work device can be returned to the target posture at an early stage, and a reduction in work efficiency due to the work device not being maintained in the target posture can be prevented.
According to the first feature of the present invention, by changing the second control gain for operating the actuator according to the detection value of the change speed detecting means, it becomes possible to cope with the state of the work place and the work form, and the attitude control. The performance of the means could be improved.

[II]
(Constitution)
The second feature of the present invention lies in the following configuration in the work device attitude changing structure for a work vehicle of the first feature of the present invention.
A traveling speed detecting means for detecting the traveling speed of the airframe is provided. The control gain changing means is configured so that the second control gain is changed to a small side when the traveling speed of the airframe is low.

(Function)
According to the second feature of the present invention, the “action” described in the preceding item [I] is provided in the same manner as the first feature of the present invention, and in addition to this, the following “action” is provided.
When the traveling speed of the airframe is on the low speed side, the posture change of the work device becomes a little slower (because the change speed of the posture change of the work device becomes small). When the actuator starts operating, if the actuator is operated at a high speed, it is conceivable that the posture of the working device becomes unstable due to the high speed operation of the actuator.

  According to the second feature of the present invention, the second control gain is changed to the smaller side when the traveling speed of the airframe becomes low. Therefore, when the actuator starts to operate according to the detected value of the changing speed detecting means, the changing speed is detected. The actuator can be set to operate at a low speed for the detection value of the means (for the change speed of the posture change of the work device), and avoid the state where the posture of the work device is not stable. Can do.

(The invention's effect)
According to the second feature of the present invention, the “effect of the invention” described in the preceding item [I] is provided in the same manner as the first feature of the present invention. In addition, the following “effect of the invention” is provided. ing.
According to the second feature of the present invention, the configuration in which the second control gain is changed to the small side when the traveling speed of the airframe becomes low can avoid a state where the posture of the work device is not stable. As a result, the performance of the attitude control means could be improved.

[III]
(Constitution)
A third feature of the present invention resides in the following configuration in the work device attitude changing structure for a work vehicle according to the first or second feature of the present invention.
The control gain changing means is configured so that the second control gain is changed to zero when the airframe enters the travel stop state.

(Function)
According to the third feature of the present invention, the “action” described in the preceding item [I] [II] is provided in the same manner as the first or second feature of the present invention. In addition, the following “action” is provided. It has.
It is conceivable that the attitude of the working device slightly changes due to vibrations of the engine or the like when the machine body is stopped.
In this case, there is no deviation between the detection value of the posture detection means and the target posture (in general, the dead zone is often set in the target posture, so the detection value of the posture detection means deviates from the target posture (dead zone). The change rate of the change in the posture of the work device may be detected by the change speed detection means (the change rate of the change in the posture of the work device may change). There). In such a state, the actuator is actuated by the detection value of the change speed detection means in the traveling stop state of the airframe, and the posture of the work device is changed.

  According to the third feature of the present invention, the second control gain is changed to zero when the aircraft is in the travel stop state, so that the change speed detecting means detects the change speed of the posture change of the work device in the travel stop state of the airframe. Even if it is done (even if the change speed of the posture change of the working device changes), the actuator is not operated by the detection value of the change speed detecting means.

(The invention's effect)
According to the third feature of the present invention, the “effect of the invention” described in the preceding paragraphs [I] and [II] is provided in the same manner as the first or second feature of the present invention. The effect of the invention is provided.
According to the third feature of the present invention, even when the change speed detecting means detects the change speed of the posture change of the work device (even if the change speed of the change posture of the work device is changed) in the traveling stop state of the aircraft, By preventing the actuator from being actuated by the detection value of the change speed detecting means, it was possible to stabilize the posture of the work device when the machine body was stopped.

[IV]
(Constitution)
A fourth feature of the present invention resides in the following configuration in any one of the working device attitude changing structures for a work vehicle according to the first to third features of the present invention.
A grounding body for following the ground to the work site is provided on the work device so as to be raised and lowered. The posture detection means is configured to detect the height from the grounding body to the work device as the posture of the work device, and the change speed detection means is configured to detect the ascending / descending speed of the grounding body as the change speed of the posture change of the work device. Constitute. Sensitivity changing means is provided for changing the ground contact tracking sensitivity of the grounding body to the work site. The control gain changing means is configured such that when the sensitivity changing means is set to the insensitive side, the second control gain is changed to the small side.

(Function)
According to the 4th characteristic of this invention, it is equipped with "action" of previous clause [I]-[III] similarly to any one of the 1st-3rd characteristics of this invention, In addition to this, It has the following “actions”.
According to a fourth aspect of the present invention, the work device is provided with a grounding body that follows the ground and follows the work ground so that the work device can freely move up and down, and the posture detection means is configured to detect the height from the grounding body to the work device as the posture of the work device. And a change speed detecting means is configured to detect the ascending / descending speed of the grounding body as a change speed of the posture change of the working device, and a sensitivity changing means for changing the grounding follow-up sensitivity to the work ground of the grounding body is provided. ing. In this case, in general, when the work place is hard and has a lot of unevenness, the sensitivity changing means is changed to the insensitive side, and when the work place is soft and has little unevenness, the sensitivity changing means is changed to the sensitive side.

If the work area is hard and there are many irregularities, the posture of the work device is likely to change, and the change speed of the posture change of the work device is likely to increase. In some cases, the posture of the work device is stabilized by suppressing a change.
In this case, according to the fourth feature of the present invention, when the sensitivity changing means is set to the insensitive side, the second control gain is changed to the small side. When the actuator starts to operate according to the detection value of the speed detection means, set the actuator to operate at a low speed for the detection value of the change speed detection means (for the change speed of the posture change of the work equipment) Therefore, the posture of the working device can be further stabilized.

(The invention's effect)
According to the fourth feature of the present invention, the “effect of the invention” described in the preceding paragraphs [I] to [III] is provided similarly to any one of the first to third features of the present invention. In addition, the following “effects of the invention” are provided.
According to the fourth feature of the present invention, in the case of including the sensitivity changing means for changing the contact tracking sensitivity of the grounding body to the work site, when the sensitivity changing means is set to the insensitive side, the second control gain is set to the small side. By being configured to be changed, it is possible to stabilize the posture of the working device when the work place is hard and there are many irregularities, and the performance of the posture control means can be improved.

[1]
As shown in FIG. 1, a link mechanism 3 is supported by a rear part of a machine body supported by right and left front wheels 1 and right and left rear wheels 2, so that the link mechanism 3 can be moved up and down. A hydraulic cylinder 4 (corresponding to an actuator) is provided, and a seedling planting device 5 (corresponding to a working device) is supported at the rear of the link mechanism 3 to constitute a riding type rice transplanter as an example of a working vehicle. Has been.

  As shown in FIG. 1, the seedling planting device 5 includes four planting transmission cases 6, a rotary case 7 supported on the left and right of the rear portion of the planting transmission case 6, and rotatably supported at both ends of the rotary case 7. A pair of planting arms 8, a plurality of grounding floats 9, a seedling platform 10, and the like are provided and configured in an 8-row planting type. Thus, as the seedling platform 10 is driven to reciprocate laterally to the left and right, the rotary case 7 is rotationally driven, and the planting arms 8 alternately take out the seedlings from the lower part of the seedling platform 10 to the surface G Plant.

  As shown in FIG. 1, a hopper 14 for storing fertilizer and four feeding units 15 in two-row units are provided on the rear side of the driver seat 13, and a blower 16 is provided on the lower side of the driver seat 13. Yes. A groover 17 is provided on the ground float 9, and a hose 18 is connected across the feeding portion 15 and the groover 17. As a result, the fertilizer in the hopper 14 is fed out by a predetermined amount by the feeding unit 15, transported through the hose 18, and supplied to the groove formed on the surface G by the grooving device 17.

[2]
Next, the raising / lowering control means (equivalent to an attitude | position control means) of the seedling planting apparatus 5 is demonstrated.
As shown in FIG. 2, an electromagnetically operated up control valve 24 for supplying hydraulic oil to the hydraulic cylinder 4 and an electromagnetically operated down control valve 25 for discharging hydraulic oil from the hydraulic cylinder 4 are provided. 23, the up and down control valves 24 and 25 are operated by duty control. When hydraulic oil is supplied to the hydraulic cylinder 4 by the lift control valve 24, the hydraulic cylinder 4 contracts and the seedling planting device 5 is lifted, and when the hydraulic oil is discharged from the hydraulic cylinder 4 by the drop control valve 25. The hydraulic cylinder 4 extends and the seedling planting device 5 is lowered.

  As shown in FIG. 2, the rear part of the center grounding float 9 (corresponding to the grounding body) is supported around the horizontal axis P1 of the seedling planting device 5 so as to be swingable up and down. A potentiometer 22 (corresponding to the posture detecting means) is fixed to a fixed part of the seedling planting device 5, and a rod 26 is connected across the detection arm 22 a of the potentiometer 22 and the front part of the ground contact float 9. The detection value B1 of 22 is input to the control device 23. As the aircraft moves, the ground contact float 9 at the center follows the ground surface G, and the height from the surface G (center ground float 9) to the potentiometer 22 can be detected by the detection value B1 of the potentiometer 22. It is possible to detect the height from the rice field G (center grounding float 9) to the seedling planting device 5.

  As shown in FIG. 2, a sensitivity dial 27 (corresponding to sensitivity changing means) that can be manually operated is provided, and the operation position of the sensitivity dial 27 is input to the control device 23. The state shown in FIG. 2 is a state in which the sensitivity dial 27 is operated to the neutral position N, and the detection value B1 of the potentiometer 22 in which the bottom surface of the center grounding float 9 is horizontal is the planting set height A0 (set depth). )) Is set as a set detection value A1 (corresponding to the target posture).

In the state shown in FIG. 2, the ground contact float 9 at the center follows the ground surface G, while the seedling planting device 5 moves up and down, the seedling planting from the surface G (center ground float 9) accordingly. The height to the attaching device 5 (planting depth of the seedling) is about to change.
As described in [4] and [5], which will be described later, the potentiometer 22 detects the height (the seedling planting depth) from the field surface G (center grounding float 9) to the seedling planting device 5 and the potentiometer. The control device 23 operates the raising and lowering control valves 24 and 25 so that the detected value B1 of 22 becomes the set detected value A1 (planting set height A0 (set depth)), and the hydraulic cylinder 4 controls the seedling planting. The attaching device 5 is driven up and down, and the seedling planting device 5 is maintained from the field G to the planting set height A0 (set depth), and the seedling planting depth by the seedling planting device 5 is set. The depth is maintained (elevation control means).

As shown in FIG. 2, when the sensitivity dial 27 is operated to the neutral position N, the detection value B1 of the potentiometer 22 in which the bottom surface of the center grounding float 9 is horizontal is set to the planting set height A0 (set depth). ) Is set as the set detection value A1 corresponding to.
When the mud on the surface G is soft (the water on the surface G is much) and the unevenness on the surface G is small, the sensitivity dial 27 is generally operated from the neutral position N to the sensitive side. When the sensitivity dial 27 is operated from the neutral position N to the sensitive side, the set detection value A1 is changed to a slightly lower side corresponding to the operation position of the sensitivity dial 27. As a result, the bottom surface of the center ground float 9 at the set detection value A1 is slightly downward, the ground contact area of the center ground float 9 to the field G increases, and the center ground float 9 follows the field G sensitively. (Equivalent to the state in which the ground contact sensitivity of the grounding body to the work site has been changed to the sensitive side).

  When the mud on the surface G is hard (the water on the surface G is small) and the surface G is rough, the sensitivity dial 27 is generally operated from the neutral position N to the insensitive side. When the sensitivity dial 27 is operated from the neutral position N to the insensitive side, the set detection value A1 shown in FIG. 2 is changed to a slightly higher side corresponding to the operation position of the sensitivity dial 27. As a result, the bottom surface of the center grounding float 9 at the set detection value A1 is slightly upward, the grounding area of the center grounding float 9 to the surface G is reduced, and the center grounding float 9 follows the surface G insensitively. (Equivalent to the state where the ground contact sensitivity of the grounding body to the work site is changed to the insensitive side).

[3]
Next, the duty control (duty T1) of the raising and lowering control valves 24 and 25 will be described.
As shown in FIG. 2, the raising control valve 24 is configured to be electromagnetically operated at two positions of a hydraulic oil supply position and a cutoff position, and the lowering control valve 25 is arranged at a hydraulic oil discharge position and a cutoff position. It can be operated in two positions and is constructed as an electromagnetic operation type. As shown in FIG. 3, duty control is performed in which the ascending and descending control valves 24 and 25 are repeatedly operated at high speed to the supply position (discharge position) and the shut-off position, and the supply position (discharge position) with respect to the unit time T3. ) By changing the duty ratio T1, which is the ratio (T4 / T3) of the time T4 that is operated at (), the flow rate of the hydraulic oil supplied from the ascending control valve 24 (the operating oil discharged from the descending control valve 25) Flow rate) can be changed.

  Thereby, the duty ratio T1 is set by the control device 23, and the raising and lowering control valves 24, 25 are repeatedly set at the supply position (discharge position) and the cutoff position at a high speed by the operation signal (duty ratio T1) of the control device 23. By operating, the flow rate control of the hydraulic oil is performed by the ascending and descending control valves 24 and 25, and the expansion / contraction speed (hydraulic fluid flow rate) of the hydraulic cylinder 4 can be arbitrarily set and changed. As shown in FIG. 2, a potentiometer 11 for detecting the vertical angle of the link mechanism 3 is provided, and a detection value of the potentiometer 11 is input to the control device 23, and the hydraulic cylinder 4 is stopped and expanded and contracted based on the detection value of the potentiometer 11. The operation and stop position are detected, and the detection value of the potentiometer 11 is differentiated to calculate the expansion / contraction speed of the hydraulic cylinder 4.

In the duty control, the duty ratio T1 can be set from 0% to 100%. However, in the hydraulic cylinder 4 and the ascending / descending control valves 24 and 25, even if the duty ratio T1 is set from 0% to 100%, the flow rate of the hydraulic fluid is too small in the vicinity of the duty ratio T1 being 0%. The hydraulic cylinder 4 does not expand and contract. When the duty ratio T1 is close to 100%, the flow rate of the hydraulic oil is saturated, and the expansion / contraction speed (hydraulic oil flow rate) of the hydraulic cylinder 4 does not change even if the duty ratio T1 is changed.
There are individual differences in the ascending and descending control valves 24 and 25 that are produced in large numbers. For example, the contraction speed of the hydraulic cylinder 4 (the flow rate of hydraulic oil when the one ascending control valve 24 is operated at the duty ratio T1. ) And the contraction speed (the flow rate of hydraulic oil) of the hydraulic cylinder 4 may be different when another lift control valve 24 is operated with the same duty ratio T1.

The correction mode is set in the control device 23 for the state as described above, and the correction mode is activated when the up and down control valves 24 and 25 are replaced or maintained at the time of shipment from the production factory. .
As shown in FIG. 1, in a state where a standard number of seedlings are placed on the seedling stage 10 (for example, a state where one or two seedlings are placed on one seedling surface of the seedling stage 10), When the correction mode is activated, as shown in FIG. 4, the operation signal (duty ratio T1) of the control device 23 for the ascent control valve 24 gradually increases from 0%, and the hydraulic cylinder 4 is contracted from the stopped state. Is detected. In this case, in general, the hydraulic cylinder 4 does not contract at an extremely low speed close to a stopped state, but suddenly starts contracting at a certain contraction speed (hydraulic oil flow rate) V01. There are many cases.

  As shown in FIG. 4, in the range of the duty ratio T1 in which the operation signal (duty ratio T1) of the control device 23 and the flow rate of hydraulic oil (the contraction speed of the hydraulic cylinder 4) are considered to have a linear relationship, Possible duty ratios T12 and T13 are set in advance. Thereby, the raising control valve 24 is operated by the operation signal (duty ratio T12) of the control device 23, and the contraction speed (flow rate of hydraulic oil) V2 of the hydraulic cylinder 4 at this time is detected based on the detection value of the potentiometer 11. Next, the raising control valve 24 is operated by the operation signal (duty ratio T13) of the control device 23, and the contraction speed (flow rate of hydraulic fluid) V3 of the hydraulic cylinder 4 at this time is based on the detected value of the potentiometer 11. Detected.

As shown in FIG. 4, a relational expression Y1 as a linear function is set based on the duty ratios T12 and T13 and the contraction speeds (flow rates of hydraulic oil) V2 and V3 of the hydraulic cylinder 4. When the relational expression Y1 is extended to the duty ratio T11, it is assumed that the contraction speed (hydraulic oil flow rate) V1 of the hydraulic cylinder 4 having the duty ratio T11 according to the relational expression Y1 is obtained.
As described above, the contraction speed (hydraulic oil flow rate) V01 of the hydraulic cylinder 4 when the hydraulic cylinder 4 starts contracting operation from the stopped state at the duty ratio T11 and the hydraulic cylinder 4 of the duty ratio T11 according to the relational expression Y1. Even if the contraction speed (hydraulic oil flow rate) V1 does not match, the difference between the contraction speeds (hydraulic oil flow rates) V01 and V1 of the hydraulic cylinder 4 should be small, so the hydraulic cylinder 4 having the duty ratio T11 according to the relational expression Y1. The contraction speed (hydraulic oil flow) V1 is set as the contraction speed (hydraulic oil flow) when the hydraulic cylinder 4 starts the contraction operation from the stopped state at the duty ratio T11.

  As a result, in the ascending control valve 24, the relational expression Y1 is set in the range of the duty ratios T11 and T13 and the contraction speeds (hydraulic oil flow rates) V1 and V3 of the hydraulic cylinder 4. The lowering control valve 25 is operated in the same manner as the above-described raising control valve 24. In the lowering control valve 25, the duty ratios T11 and T13 and the contraction speeds (hydraulic oil flow rates) V1 and V3 of the hydraulic cylinder 4 are set. In the range, the relational expression Y1 is set.

[4]
Next, the first half of the operation of the lifting control means will be described with reference to FIG.
The detected value B1 of the potentiometer 22 is sent to the control device 23 as the height from the surface G (center grounding float 9) to the seedling planting device 5 (height from the surface G (center grounding float 9) to the potentiometer 22). When input (step S1), the difference between the detected value B1 of the potentiometer 22 and the set detected value A1 is detected as a deviation B3 (B3 = A1-B1) (corresponding to the deviation between the detected value of the posture detecting means and the target posture). (Step S2).

  In this case, if the deviation B3 is a positive value, the height from the field G (center grounding float 9) to the seedling planting device 5 (the height from the field G (center grounding float 9) to the potentiometer 22). Means that it is located on the upper side (higher side) than the planting set height A0 (set depth), and if the deviation B3 is a negative value, from the surface G (center grounding float 9) The height to the seedling planting device 5 (the height from the surface G (center grounding float 9) to the potentiometer 22) is lower (lower side) than the planting set height A0 (set depth). It means that

  The detection value B1 of the potentiometer 22 is differentiated to detect the ascending / descending speed of the center grounding float 9, thereby detecting the ascending / descending speed B2 of the seedling planting device 5 (corresponding to the changing speed of the posture change of the working device). (Step S3) (corresponding to change speed detecting means). If the raising / lowering speed B2 of the seedling planting device 5 is a positive value, it means that the seedling planting device 5 is in an elevated state, and if the raising / lowering speed B2 of the seedling planting device 5 is a negative value, This means that the planting device 5 is in the lowered state.

A dead zone H1 is set for the set detection value A1. When the detected value B1 of the potentiometer 22 is in the dead zone H1 of the set detected value A1 (step S4), the first control gain K1 is set to “0” (step S5), and the detected value B1 of the potentiometer 22 is When the set detection value A1 is out of the dead zone H1 (step S4), the first control gain K1 is set to a constant value stored in advance (step S6).
In this case, the first control gain K1 is not configured to be set to a constant value stored in advance, but the solid line Y3 and the alternate long and short dash line Y4 in FIG. As shown, the first control gain K1 may be set according to the operation position of the sensitivity dial 27.

  At the lifting speed B2 of the seedling planting device 5, the dead zone H2 is set with respect to “0” (the state where the lifting of the seedling planting device 5 is stopped) (the dead zone H2 is sufficiently larger than the dead zone H1). small). When the raising / lowering speed B2 of the seedling planting device 5 is in the dead zone H2 of “0” (step S7), the second control gain K2 is set to “0” (step S8). When the raising / lowering speed B2 of the seedling planting device 5 is out of the dead zone H2 of “0” (step S7), the second control gain K2 is set according to the operating position of the sensitivity dial 27 at this time (step S7). S9) (corresponding to control gain changing means).

As shown by the solid line Y3 in FIG. 5, when the sensitivity dial 27 is operated from the neutral position N to the sensitive side, the second control gain K2 is set to a high constant value K22. When the sensitivity dial 27 is operated to the insensitive side from the neutral position N, the operating position of the sensitivity dial 27 is insensitive to the value K22 of the second control gain K2 and the small value K21 (not “0”). The more the second control gain K2 is set to a smaller value.
In this case, as shown by a one-dot chain line Y4 in FIG. 5, when the sensitivity dial 27 is operated from the neutral position N to the insensitive side, the second control gain K2 is set to a low constant value K23. Also good. In the solid line Y3 and the alternate long and short dash line Y4 in FIG. 5, the second control gain K2 may be set to a higher value as the sensitivity dial 27 is operated from the neutral position N to the sensitive side.

[5]
Next, the second half of the operation of the lifting control means will be described with reference to FIG.
As described in the preceding item [4], the deviation B3 (positive or negative value), the raising / lowering speed B2 (positive or negative value) of the seedling planting device 5, the first and second control gains K1, K2 (positive) Value) is obtained, the sum of the value obtained by multiplying the deviation B3 by the first control gain K1 and the value obtained by multiplying the lifting speed B2 of the seedling planting device 5 by the second control gain K2 is the target of the hydraulic cylinder 4. It is calculated | required as expansion-contraction speed (flow volume of hydraulic fluid) VK (step S10).

  In step S10, the height from the field surface G (center grounding float 9) to the seedling planting device 5 (the height from the field surface G (center grounding float 9) to the potentiometer 22) is the planting set height A0 ( The higher the setting depth is, the higher the value is (the higher the value is), the lower the value is (the lower the value is)). Value (upper side (high side)) or negative value on the large side (lower side (low side)).

  In step S10, the height from the field surface G (center grounding float 9) to the seedling planting device 5 (the height from the field surface G (center grounding float 9) to the potentiometer 22) is the planting set height A0 ( In a state where it is off the upper side (higher side) than the set depth), the raising / lowering speed B2 of the seedling planting device 5 is a positive positive value (the seedling planting device 5 is in a high-speed rising state). The target expansion / contraction speed (hydraulic oil flow rate) VK of the hydraulic cylinder 4 is further corrected to a positive large value, and the raising / lowering speed B2 of the seedling planting device 5 is a negative large value (seedling). As the planting device 5 is in a lowering state at a higher speed), the target expansion / contraction speed (hydraulic oil flow rate) VK of the hydraulic cylinder 4 is corrected to a positive small value.

  In step S10, the height from the field surface G (center grounding float 9) to the seedling planting device 5 (the height from the field surface G (center grounding float 9) to the potentiometer 22) is the planting set height A0 ( In a state where it is below the set depth) (low side), the higher the ascending / descending speed B2 of the seedling planting device 5 is on the negative large side (the seedling planting device 5 is in a high-speed descending state). The target expansion / contraction speed (hydraulic oil flow rate) VK of the hydraulic cylinder 4 is further corrected to a negative large value, and the raising / lowering speed B2 of the seedling planting device 5 is a positive large value. As the seedling planting device 5 is in a higher speed rising state), the target expansion / contraction speed (hydraulic oil flow rate) VK of the hydraulic cylinder 4 is corrected to a negative small value.

  Based on the target expansion / contraction speed (hydraulic oil flow rate) VK of the hydraulic cylinder 4 obtained as described above, the duty ratio T1 is obtained based on the relational expression Y1 shown in FIG. 4 (step S11). When the target expansion / contraction speed (hydraulic oil flow rate) VK of the hydraulic cylinder 4 is lower (smaller side) than the contraction speed (hydraulic oil flow rate) V1 of the hydraulic cylinder 4, the duty ratio T1 is set to T11. If the target expansion / contraction speed (hydraulic oil flow rate) VK of the hydraulic cylinder 4 is higher than the contraction speed (hydraulic oil flow rate) V3 of the hydraulic cylinder 4, the duty ratio T1 is set to T13. Is done.

  When the deviation B3 is a positive value, the height from the field G (center grounding float 9) to the seedling planting device 5 (height from the field G (center grounding float 9) to the potentiometer 22) is planted. The height of the lowering control valve 25 is higher than the set height A0 (set depth), and the lowering control valve 25 is moved to the discharge position and the shut-off position at a high speed by the operation signal (duty ratio T1) of the control device 23. The hydraulic plant 4 is expanded at the target expansion / contraction speed (hydraulic oil flow) VK of the hydraulic cylinder 4 while the hydraulic oil flow control is performed by the lowering control valve 25, and the seedling planting device 5 is operated. It descends (step S12).

  When the deviation B3 is a negative value, the height from the field surface G (center grounding float 9) to the seedling planting device 5 (the height from the field surface G (center grounding float 9) to the potentiometer 22) is planted. The height control valve 24 is moved to the supply position and the shut-off position by the operation signal (duty ratio T1) of the control device 23 because it is out of the lower side (lower side) than the set height A0 (set depth). While being operated repeatedly at high speed and the flow rate of the hydraulic oil is controlled by the lift control valve 25, the hydraulic cylinder 4 is contracted at the target expansion / contraction speed (hydraulic oil flow) VK of the hydraulic cylinder 4, and the seedling planting device 5 is operated. Rises (step S12).

  Thereby, steps S1 to S12 are repeated, and the seedling planting device 5 is driven up and down by the hydraulic cylinder 4 so that the detection value B1 of the potentiometer 22 enters the dead zone H1 of the set detection value A1, so that the seedling planting is performed. The attaching device 5 is maintained from the surface G to the planting set height A0 (set depth), and the seedling planting depth by the seedling planting device 5 is maintained at the set depth.

[First Alternative Embodiment of the Invention]
Instead of FIG. 6 in [Best Mode for Carrying Out the Invention], a configuration as shown in FIG. 7 may be used.
A traveling speed detecting means (not shown) for detecting the traveling speed of the airframe is provided. In this case, the vehicle travels so as to detect the traveling speed of the airframe by detecting the rotational speed of the transmission shaft for traveling, or to detect the rotational speed of the airframe by detecting the rotational speed of the engine (not shown). A speed detection means is configured. Step S9 shown in FIG. 6 is abolished, and steps S21 and S22 are set as shown in FIG.

  As shown in FIG. 7, when the raising / lowering speed B2 of the seedling planting device 5 deviates from the dead zone H2 of “0” (step S7), when the aircraft is in a traveling stop state or when the traveling speed of the aircraft is less than the extremely low speed VV1 In step S8, the second control gain K2 is set to “0”. When the traveling speed of the airframe is equal to or higher than the extremely low speed VV1, the second control gain K2 is set according to the traveling speed of the airframe (step S22) (corresponding to the control gain changing means).

As indicated by the solid line Y5 in FIG. 8, the second control gain K2 increases as the traveling speed of the aircraft increases between a small value K21 (not "0") and a large value K22 of the second control gain K2. Is set to a larger value, and the second control gain K2 is set to a smaller value as the aircraft travels at a lower speed.
In this case, as indicated by the one-dot chain line Y6 in FIG. 8, when the traveling speed of the aircraft is between the extremely low speed VV1 and the intermediate speed VV3, the second control gain K2 is set to a small constant value K23. If the traveling speed is between the intermediate speed VV3 and the maximum speed VV2, the second control gain K2 may be set to a large constant value K22.

[Second Embodiment of the Invention]
Instead of FIG. 4 of [Best Mode for Carrying Out the Invention] [First Alternative Embodiment of the Invention], a configuration as shown in FIG. 9 may be used.
As shown in FIG. 9, in a state where a standard number of seedlings are placed on the seedling stage 10 (for example, a state where one or two seedlings are placed on one seedling surface of the seedling stage 10), When the correction mode is activated, the operation signal (duty ratio T1) of the control device 23 for the ascending control valve 24 gradually increases from 0%, and the duty ratio T11 at which the hydraulic cylinder 4 starts contracting operation from the stopped state is set. Detected.

  As shown in FIG. 9, in the range of the duty ratio T1 in which the operation signal (duty ratio T1) of the control device 23 and the flow rate of hydraulic oil (the contraction speed of the hydraulic cylinder 4) are considered to have a linear relationship, Possible duty ratios T12 and T13 are set in advance. Thereby, the raising control valve 24 is operated by the operation signal (duty ratio T12) of the control device 23, and the contraction speed (flow rate of hydraulic oil) V2 of the hydraulic cylinder 4 at this time is detected based on the detection value of the potentiometer 11. Next, the raising control valve 24 is operated by the operation signal (duty ratio T13) of the control device 23, and the contraction speed (flow rate of hydraulic fluid) V3 of the hydraulic cylinder 4 at this time is based on the detected value of the potentiometer 11. Detected.

  As shown in FIG. 9, a relational expression Y1 as a linear function is set based on the duty ratios T12 and T13 and the contraction speeds (hydraulic oil flow rates) V2 and V3 of the hydraulic cylinder 4. At the duty ratio T11 at which the hydraulic cylinder 4 starts contracting operation from the stopped state, the contraction speed (hydraulic oil flow rate) of the hydraulic cylinder 4 is set to “0”, and the duty ratios T11 and T12 and the contraction speed of the hydraulic cylinder 4 (hydraulic oil) ) Based on V2, a relational expression Y2 as a linear function is set.

  Thereby, in the rising control valve 24, the relational expressions Y1 and Y2 are set in the range of the duty ratios T11 and T13 and the contraction speeds “0” and V3 of the hydraulic cylinder 4. The lowering control valve 25 is operated in the same manner as the above-described operation of the raising control valve 24. In the lowering control valve 25, the relationship is within the ranges of the duty ratios T11 and T13 and the contraction speeds “0” and V3 of the hydraulic cylinder 4. Expressions Y1 and Y2 are set.

[Third Another Embodiment of the Invention]
In the above-mentioned [Best Mode for Carrying Out the Invention] [First Alternative Embodiment of the Invention] [Second Alternative Embodiment of the Invention], the detected value B1 of the potentiometer 22 is subjected to differential processing and seedling planting. Rather than detecting the ascending / descending speed B2 of the device 5, a dedicated ascending / descending speed sensor (corresponding to the change speed detecting means) is provided, or an ascending / descending acceleration sensor (corresponding to the change speed detecting means) is provided. You may comprise so that the raising / lowering speed B2 of the apparatus 5 may be detected.

[Fourth Embodiment of the Invention]
In the above-mentioned [Best Mode for Carrying Out the Invention] [First Alternative Embodiment] to [Third Alternative Embodiment] regardless of the operating position of the sensitivity dial 27 and the traveling speed of the airframe. The second control gain K2 may be configured to be arbitrarily set and changed (including “0”) artificially.

In the above-mentioned [Best Mode for Carrying Out the Invention] [First Different Embodiment of the Invention] to [Third Another Embodiment of the Invention], depending on the operating position of the sensitivity dial 27 and the traveling speed of the aircraft. The first control gain K1 may also be changed, and the first control gain K1 can be set and changed manually (“0”) regardless of the operation position of the sensitivity dial 27 and the traveling speed of the aircraft. May also be included).
The present invention can be applied not only to a riding type rice transplanter, but also to a paddy field work machine in which a direct seeding device or a chemical spraying device is connected as a work device, an agricultural tractor, or a combiner. It can also be applied to rolling control.

Overall side view of riding rice transplanter Diagram showing the relationship between the hydraulic cylinder, center ground float, potentiometer and sensitivity dial The figure which shows the state of duty control The figure which shows the relational expression of the duty ratio in the raising and lowering control valve and the contraction (extension) speed (hydraulic oil flow rate) of the hydraulic cylinder The figure which shows the relationship between a sensitivity dial and a 2nd control gain The figure which shows the flow of operation | movement of a raising / lowering control means. The figure which shows the flow of an action | operation of a raising / lowering control means in 1st another form of implementation of invention. The figure which shows the relationship between the travel speed of a body, and the 2nd control gain in 1st another form of implementation of invention. The figure which shows the relational expression of the duty ratio in the raising and lowering control valve and the contraction (extension) speed (flow rate of hydraulic oil) of the hydraulic cylinder in the second alternative embodiment of the invention

Explanation of symbols

4 Actuator 5 Work device 9 Grounding body 22 Posture detection means 27 Sensitivity change means A1 Target posture B1 Detection value of posture detection means B2 Change speed of posture change of work equipment, lifting speed of grounding body K1 First control gain K2 Second control Gain G Work place

Claims (4)

An actuator for changing the posture of the work device connected to the airframe;
A posture detecting means for detecting the posture of the working device; and a change speed detecting means for detecting a changing speed of the posture change of the working device.
The actuator is operated at a higher speed based on the first control gain as the detection value of the attitude detection means deviates from the target attitude, and the actuator is set to the second control gain as the detection value of the change speed detection means becomes higher. Based on a posture control means that operates at a high speed based on the actuator and maintains the working device in a target posture by the actuator;
A working device attitude changing structure for a work vehicle, comprising control gain changing means capable of changing the second control gain.   2. The control gain changing means according to claim 1, further comprising travel speed detecting means for detecting a travel speed of the airframe, wherein the second control gain is changed to a smaller side when the travel speed of the airframe becomes low. The working device attitude changing structure of the described working vehicle.   The work device attitude changing structure for a work vehicle according to claim 1 or 2, wherein the control gain changing means is configured so that the second control gain is changed to zero when the airframe is stopped. A grounding body that follows the ground to the work site is provided on the working device so as to be movable up and down.
The posture detection means is configured to detect the height from the grounding body to the work device as the posture of the work device, and the change speed detection is performed so that the ascending / descending speed of the grounding body is detected as the change speed of the posture change of the work device. Constructing means
With sensitivity changing means for changing the ground contact tracking sensitivity to the work site of the grounding body,
The control gain changing means is configured such that the second control gain is changed to a small side when the sensitivity changing means is set to the insensitive side. The working device attitude change structure of the work vehicle.

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