JP2000184805A - Tillage control device for tiller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tillage control device for tiller without wasting an output of an engine while preventing the engine from stopping. SOLUTION: This control device comprises: an automatic lift control device A designed to actuate the lift driving mechanism 10 of a rotary tilling machine so that a detected value of a cover sensor 18 may agree with a target plow depth set by a plow depth-setting means 19; a plow depth-compensating controller B designed to change the target plow depth set by the plow depth-setting means 19 to a shallower side when a rotational speed of the engine is detected to be lower than a predetermined speed by detecting the rotational speed; and a vehicle speed control means C designed to reduce a moving speed of the tiller body by a vehicle speed adjusting means 24 when a rotational speed of the engine is detected to be lower than a predetermined speed by detecting the rotational speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a tiller having a rotary tiller connected to the rear of a tractor, which is more efficient and superior in terms of vehicle speed control in addition to automatic elevating control for maintaining a desired plowing depth. The present invention relates to a technique that enables a tilling operation to be performed.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Unexamined Patent Publication No. Hei 5-292803, automatic elevation control for maintaining a target plowing depth by detecting the amount of vertical swing of a rear cover and operating an elevation drive mechanism is disclosed. There is known a configuration in which a change in the attitude of a rotary cover due to sinking of an airframe is performed while correcting the change. As disclosed in Japanese Patent Publication No. Sho 63-52841, when the engine is about to stop, the control for lifting the rotary tilling apparatus so that the cultivation depth becomes shallow is performed in preference to the automatic elevating control. Compositions are also known.

[0003]

The cultivator often performs the tilling operation at the maximum number of revolutions of the engine by the full accelerator operation. As described in Japanese Patent Application Laid-Open No. 5-292803, even if the automatic raising and lowering control for maintaining the target plowing depth is performed, the plowing operation can be favorably performed without stopping the engine. However, depending on extreme hardening of the soil, the engine may be stopped even if the engine has sufficient output. In such a case, as described in JP-B-63-52841 described above,
There is a technique for stopping the automatic elevating control for maintaining the target plowing depth and temporarily reducing the plowing depth to prevent the engine from stopping.

In JP-A-5-292803, since the output of the engine is basically provided with extra power, it seems that there is much waste in the output of the engine during the tilling operation. This point has not been solved yet even if the above-mentioned technique of Japanese Patent Publication No. 63-52841 for preventing the stop of the engine is introduced, and there is room for improvement even in view of energy saving in recent years. An object of the present invention is to provide an efficient tillage control device that can use an engine output without waste while preventing engine stoppage by organically adding vehicle speed control to automatic raising and lowering control of a rotary tillage device. And

[0005]

Means for Solving the Problems [Configuration of Claim 1] The configuration of claim 1 is to configure the following in a tilling control device of a tilling machine. A rotary tilling device that is connected to the airframe so as to be able to drive up and down, a rear cover that is provided at the rear of the rotary tilling device and that can swing up and down following the ground, and a cover sensor that detects the amount of vertical swing of the rear cover, And a cultivation depth setting means for setting a target cultivation depth of the rotary cultivator, and actuating an elevating drive mechanism of the rotary cultivator so that a detection value of the cover sensor matches the target cultivation depth set by the cultivation depth setting means. In addition to providing automatic elevating control means, a rotational speed detecting means for detecting an engine rotational speed, and a vehicle speed adjusting means for freely changing the speed of the traveling transmission are provided, and the engine rotational speed is determined based on the detected engine rotational speed. When the rotation speed becomes lower than the rotation speed, the cultivation depth correction control unit that changes the target cultivation depth set by the cultivation depth setting unit to a shallower side, and the engine rotation speed based on the detection of the engine rotation speed. When There becomes lower than a predetermined rotational speed, it is provided with a vehicle speed control means to slow down the running speed of the aircraft by the vehicle speed adjustment means.

According to the configuration of claim 1, when the engine speed becomes lower than a predetermined speed,
The target tillage depth set by the tillage depth setting means is changed to a shallower side by the tillage depth correction control means. In other words, when the engine load exceeds the allowable load and the output of the engine tends to be insufficient, the target plowing depth is changed to a shallower side. For example, in a soft field, the piling up of the plowed soil is lower than in the case of the standard soil quality, and the conventional lifting control shifts the plowing depth to a deeper side and increases the engine load. The target cultivation depth is changed to a shallower side in accordance with the increase in. This makes it possible to match the plowing depth to the target plowing depth even in a soft field, and to prevent the engine from stopping due to an increase in the engine load. According to the configuration of claim 1, when the engine speed becomes lower than the predetermined speed and the engine output runs out of power, the vehicle speed control means lowers the running speed of the body, and the engine output and engine load are reduced. Is in a state of being balanced.

According to the first aspect of the present invention, in the tilling control device for a cultivator, the vehicle speed control means and the cultivation depth correction control means are added to the automatic elevating control means so that the engine can be controlled. The output was effectively used without waste, and the efficiency of the tillage work was improved.

According to a second aspect of the present invention, in the configuration of the first aspect, when the engine speed becomes higher than a predetermined speed based on the detection of the engine speed, the cultivation depth setting means may be used. The cultivation depth correction control means is configured to change the set target cultivation depth to a deeper side.

[Function of Claim 2] According to the structure of Claim 2, similar to the case of Claim 1, the preceding claim [Action of Claim 1]
And the following "action" in addition to the above. According to the configuration of claim 2,
When the engine speed becomes higher than a predetermined speed and the engine load becomes lighter and the engine output becomes slightly excessive, the target plowing depth is changed to a deeper side. For example, in a hard field, the height of the plowed soil is higher than in the case of the standard soil, and the conventional load control causes the plowing depth to shift to a shallower side, thereby reducing the engine load. The target plowing depth is changed to a deeper side according to the reduction amount of. This makes it possible to match the plowing depth to the target plowing depth even in a hard field, and the engine load does not become too heavy.

According to the structure of the second aspect, in the tilling control device of the cultivator, the vehicle speed control means and the cultivation depth correction control means are added to the automatic elevating control means, so that the engine can be controlled. The output was effectively used without waste, and the efficiency of the tillage work was improved.

According to a third aspect of the present invention, in the first or second aspect, when the engine speed becomes higher than a predetermined speed based on the detection of the engine speed, the vehicle speed adjusting means. The vehicle speed control means is configured to increase the traveling speed of the aircraft.

[Function of Claim 3] According to the structure of Claim 3, similar to the case of Claim 1 or 2, the "function" of the preceding claim [Function of Claim 1] or [Function of Claim 2] is obtained. It has the following “action” in addition to this.
According to the configuration of claim 3, in a state where there is no risk of the engine being stopped, if there is enough power in the engine output, the traveling speed of the body is increased by that much. As a result, the output of the engine and the load of the engine are balanced, so that the tillage work is not performed while the output of the engine is slightly excessive as in the conventional case, and the output of the engine can be utilized without waste. As a result, the mechanical efficiency is improved, for example, the maximum efficiency can be exhibited. Even if the same engine speed is set, the average value of the tilling operation speed can be increased as compared with the conventional case, and the tilling area per unit time can be increased.

According to the third aspect of the present invention, in the tilling control device for a cultivator, the vehicle speed control means and the cultivation depth correction control means are added to the automatic elevating control means so that the engine can be controlled. The power can be used effectively without waste, the efficiency of tilling work has been improved, and the maximum efficiency has been achieved by increasing the speed of tilling work.

According to a fourth aspect of the present invention, in the first aspect, the cover sensor is detected after the traveling speed of the body is changed by the vehicle speed adjusting means. A maximum speed control means is provided for linking the vehicle speed control means and the automatic elevating control means so as to reduce the running speed of the body when the value does not match the target plowing depth.

[Action of Claim 4] According to the structure of Claim 4, the same as any one of Claims 1 to 3, the above-mentioned [Action of Claim 1] to [Action of Claim 3]. And the following "action" in addition to the above. When the traveling speed of the body gradually increases by the vehicle speed control means, it is considered that the tilling ability of the rotary tilling device cannot finally catch up, and the rotary tilling device is rebounded on the ground and tends to float. In such a state, the cover sensor outputs an erroneous detection value indicating that the rear cover hangs down and the cultivation depth has become shallow even though satisfactory plowing has not been performed, and the cultivation depth is reduced by the automatic elevation control means. As the deepening operation takes place, more and more rotary tillers may bounce back to the ground, resulting in an out-of-control condition in which the target tillage depth cannot be reached indefinitely.

According to the fourth aspect of the invention, after the traveling speed of the vehicle body is changed by the vehicle speed control means, if the automatic lifting / lowering control means becomes uncontrollable as described above, the traveling speed of the vehicle body is reduced. Therefore, the lifting phenomenon of the rotary tilling device can be stopped, and the automatic lifting control means can be returned to a normal operating state.

According to the fourth aspect of the present invention, in the tilling control device for the cultivator, the automatic elevating control means is in an uncontrollable state due to the traveling speed of the body being too high. Without saying, it was possible to further enhance the tilling control device which is excellent in the efficiency and efficiency of the tilling operation while maintaining the state of functioning normally.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. The tiller is shown in FIG.
The vehicle includes a front wheel 1, a rear wheel 2, an engine 3, a main clutch 4, a mission 5, a control panel 6, a three-point unequal side elevating link mechanism 7, a rotary tillage device 8, a machine body 9, and a lift cylinder 10. The lifting link mechanism 7 includes a lift arm 11, a top link 12, a lower link 13, a lift rod 14, and the like. The rotary tilling device 8 pivotally supports the tilling claws 17, the rotary cover 15, and the rotary cover 15. The rear cover 16 is provided.

The structure of each part will be briefly described with reference to FIGS. The power that has passed through the main clutch 4 is transmitted to the rear wheels 2 via a main transmission mechanism a, an auxiliary transmission mechanism (not shown), and a differential mechanism b.
And transmitted to the PTO shaft 23 via the PTO transmission mechanism c. The main transmission mechanism a includes a hydraulic cylinder (not shown) for driving shift operation, and a rotary transmission operation valve 25.
A first geared motor 24 for operating an electromagnetic valve type (which may be an electromagnetic valve type) and a traveling hydraulic clutch (not shown);
Traveling shift lever 2 having first potentiometer 26a
The gear shift operation is performed by the operation No. 6 and the power shift structure is known (for example, JP-A-5-10493).

A pinion shaft 2 for transmitting power to the differential mechanism b
Speed sensor 28 for detecting the number of revolutions per unit time of the vehicle 7
Is calculated from the detection of the vehicle speed sensor 28 to determine the traveling speed of the aircraft 9. It is convenient to provide a display device 35 that indicates the current gear position and whether the mode is the automatic mode or the manual mode. In this tiller, the rear cover 1
6. Automatic lifting control for raising and lowering the rotary tillage device 8 so as to keep the plowing depth constant based on the vertical swing amount of 6, and vehicle speed control for increasing and decreasing the traveling speed of the aircraft 9 when the automatic lifting control is activated. I'm trying to do it.

Automatic Elevating Control Means A As shown in FIGS. 1 and 2, an automatic elevating control means A for maintaining the plowing depth of the rotary tillage device 8 at a target plowing depth is provided. A cover sensor 18 composed of a potentiometer that detects the amount of vertical swing of the rear cover 16 that can swing vertically following ground contact is provided on the rotary tillage device 8,
A tillage setting dial 19 for setting a target tillage depth of the rotary tillage device 8 is provided. The circuit is configured to operate the control valve V1 of the lift cylinder 10 so that the detection value of the cover sensor 18 coincides with the target plowing depth set by the plowing depth setting dial 19. Have been.

Tillage Depth Correction Control Means B As shown in FIGS. 1 and 2, the tillage depth correction control means B includes an engine rotation sensor 20. The target plowing depth is corrected to a shallower side when the rotation speed becomes larger than the permissible setting range set by the means 22, and the target plowing depth is corrected to a deeper side when the rotation speed becomes larger than the permissible setting range. Is what you do. As an actual operation, when the engine speed is too low, the rotary tilling device 8 is raised, and when the engine speed is too high, the rotary cultivating device 8 is lowered. 10 are linked.

In practice, the target value of the cover sensor 18 is corrected by fuzzy control based on the amount of change in the engine speed and the rate of change in the engine speed. The engine speed at a stable tillage load after the start of the tillage operation with the accelerator lever 21 set is detected, and the reference load at that time is determined and stored from the difference from the engine speed at no load. The fluctuating engine speed is detected from time to time, and the predicted load predicted from the difference between the actual engine speed and the no-load engine speed is compared with the reference load. Correct the depth. The correction amount of the target plowing depth based on the difference between the reference load and the predicted load is stored in the form of map data or the like, and the correction amount is finally determined based on fuzzy inference.

During the operation of the automatic elevating control means A, the tillage depth correction control means B is operated due to a change in soil quality, etc., and when the engine speed is restored after the target plowing depth is changed, the original automatic elevating control state is returned. Return to For example, if the cultivation depth becomes too deep due to the soft land and the engine speed decreases too much, the target cultivation depth will be shallow and the engine speed will recover quickly, but the original standard field condition will remain as it is. Returning to, the cultivation depth becomes shallower, and the engine speed increases this time. In this case, the tillage depth correction control means B operates again, the target tillage depth is changed to a deeper side, and returns to the original target tillage depth. The automatic raising and lowering control for maintaining the plowing depth within a predetermined range by the automatic raising and lowering control means A is called cover auto.
The combination of the control and the tillage depth correction control means B will be referred to as mixing control. Mixing control is cover MC auto (MC is M
ix Control).

Vehicle Speed Control Means C The vehicle speed control means C controls the airframe 9 when the engine speed increases.
Of the aircraft 9 when the engine speed is reduced
The first geared motor 24 is operated based on the detection of the engine rotation sensor 20 so as to maintain the engine rotation speed in a predetermined rotation speed range determined by the operation position of the accelerator lever 21 by lowering the traveling speed of the engine.

When the accelerator lever 21 is operated, the engine speed and the maximum torque of the operation position of the accelerator lever 21 under no load are determined, and the rated torque (about 8% of the maximum torque) is determined.
(Set to 0%), the traveling speed of the aircraft 9 is controlled so that the load torque becomes a value near the rated torque. For example, assume that the traveling speed of the aircraft 9 is controlled so that the load torque is 110% or less of the rated torque, and if the load torque is 50% of the rated torque,
Since 50% <110%, the load torque at the time of shifting to the one-step high-speed side from this state is predicted. The control is such that if the predicted load torque is 110% or less of the rated torque, the speed is shifted up by one speed, and if the estimated load torque is more than 110%, the speed is not shifted. The rated torque is set in consideration of a margin, and the maximum load torque is about 125% of the rated torque.

When the output of the engine 3 has room,
The output of the engine 3 becomes insufficient due to a change in soil properties, such as increasing the traveling speed of the fuselage 9 to increase the efficiency of the tilling operation, and the load torque actually exceeds α times the rated torque (eg, 1.1 times). When it becomes, the running speed of the aircraft 9 is reduced to increase the torque. Actually, in the allowable setting range of the engine speed determined by the operation position of the accelerator lever 21 (appropriate torque range, engine speed corresponding to 110% or less of the rated torque), the engine speed (rated torque) closest to the lower limit value 110% or less at 110% or less
Is controlled to appear. This is equivalent to providing a dead zone, and has the advantage that hunting due to frequent shifts in shifting can be avoided. Thereby, the torque generated at the set engine speed can be utilized to the utmost, and the tilling operation can always be performed in the maximum efficiency region.

There is a condition for application of the linkage control means E and the vehicle speed control means C. When the engine speed fluctuates moderately, the vehicle speed control means C is executed, and when the engine speed fluctuates rapidly and largely, the tillage depth correction control means B is executed (the cover MC auto operates). In order to perform this control, linkage control means E
(See FIG. 2). The first calculating means D1 for obtaining a moving average of the engine speed in a state where the sampling number of the detected value of the engine speed sensor 20 is relatively small, and in a state where the sampling number of the detected value of the engine speed sensor 20 is relatively large. A second calculating means D2 for calculating a moving average of the numbers is provided, the tillage depth correction control means B is executed based on the calculation result of the first calculating means D1, and the vehicle speed control is performed based on the calculation result of the second calculating means D2. The linkage control means E is configured so that the means C is executed.

Assuming that there is a graph (solid line) of the change over time of the engine speed as shown in FIG. 4, the first arithmetic means D1 calculates a moving average calculated by sampling, for example, three detection values per unit time. Based on the graph (dashed line), the tillage depth correction control means B is operated, and the second calculation means D2
, The vehicle speed control means C is operated based on a graph (two-dot chain line) based on a moving average calculated by sampling, for example, six detection values per unit time. In the case where the number of samplings is three, a fluctuation state of the engine speed close to the raw data appears while the extreme peak is alleviated, and is suitable as data of the tillage depth correction control means B. When the number of samplings is six, the fluctuation of the engine speed is remarkably mitigated, and the rapid and large fluctuation state is replaced with a gentle and small fluctuation state, which is suitable as data of the vehicle speed control means C.

As shown in FIG. 2, after the traveling speed of the airframe 9 is changed by the operation of the first geared motor 24, an uncontrollable state in which the actual plowing depth does not match the target plowing depth occurs. When this occurs, the first geared motor 24
And a maximum speed control means F for linking the automatic lifting control means A with the automatic lifting control means A.

As shown in FIG. 2, the power saving control means G is a waste engine 3
To improve fuel efficiency and reduce noise. When the traveling speed of the body 9 that is revealed by the operation of the vehicle speed control means C is out of the traveling speed range set in advance by the vehicle speed setting device 29, the engine speed is changed prior to the operation of the vehicle speed control means C. Thus, the link between the governor 40, the vehicle speed setting device 29 and the vehicle speed sensor 28 is the power saving control means G. Actually, a potentiometer for detecting the operation position of the accelerator lever 21 and the governor 4
The second geared motor 30 for operating the zero is also linked.

If the traveling speed of the body 9 exceeds the set value of the vehicle speed setting unit 29 in a state where the accelerator lever 21 is operated, the accelerator (governor 40) is throttled so as to enter the traveling speed range, and the engine speed is reduced. Conversely, when the value falls below the set value, the accelerator (governor 40) is opened to control the engine speed to increase, and the traveling speed of the aircraft 9 is also controlled. If the output of the engine 3 has enough power, the accelerator (governor 40) is throttled, and if the output of the engine 3 is insufficient, the accelerator (governor 40) is opened to obtain the minimum output state for displaying the set value. This is to control, and waste of the output of the engine 3 can be eliminated. The limit of the throttle amount of the accelerator (governor 40) is regulated by whether or not the rotation speed of the PTO shaft 23 is secured.

Next, the operation of the actual tillage control will be described. As shown in FIG. 2, automatic elevation control means A, tillage depth correction control means B, vehicle speed control means C, first and second calculation means D1, D2, linkage control means E, maximum speed control means F, labor saving control means G is provided in the control device 31, and various levers, setting devices, sensors, operation motors, and the like are linked to the control device 31. FIGS. 3 and 5 to 9 show various flowcharts of the tillage control, and the following description will be made with reference to these flowcharts.

As shown in FIGS. 3 and 2, the mode change switch 32 is operated to select the maximum efficiency vehicle speed control mode (automatic operation mode), the energy saving cultivation vehicle speed control mode (automatic operation mode), or the manual operation mode. I do. When the maximum efficiency vehicle speed control mode or the energy-saving cultivation vehicle speed control mode is selected and the control is being executed, if a non-tiling work state is set, the control is locked in this state. The determination as to whether or not it is in the non-tilling operation state is made, for example, by a forced ascending switch (pumper switch) 36 or a position lever (FIG. (Not shown) to the ascending side.
6, the main lever (clutch switch 37) is disengaged, the switching lever 34 of the forward / reverse switching mechanism is operated to the neutral position, and the switching lever 34 of the forward / reverse switching mechanism is turned on. For example, the forcible raising switch 36 or the position lever may be operated to the ascending side in the state of being operated to the reverse position.

If the gear is manually shifted (moving the shift lever 26) while the maximum efficiency vehicle speed control mode or the energy-saving cultivation vehicle speed control mode is being executed, the automatic operation mode is released, and the operation mode is changed to the manual operation mode. It is designed to switch. When the mode is switched to the manual operation mode, the vehicle speed control is canceled (becomes manual), but the mixing control is continued. In this case, the automatic operation mode may be released by a brake operation (depressing the brake pedal 38). Next, the automatic operation mode will be described.

(I) When the maximum efficiency vehicle speed control mode is selected (FIGS. 5 and 6) First, the initial characteristics are set, and the initial running speed, the target plowing depth, the PTO speed, and the engine speed of the machine body 9 during the tilling operation. The number (operation position of the accelerator lever 21) and the like are set in advance in consideration of field conditions and the like (step # 1), and the tilling operation is started by operating the position lever (step # 2).

After the start of the tilling operation, the fluctuation of the engine speed while maintaining the target tilling depth is a predetermined level (for example, ± 10
rpm) or less (step # 3), the rated engine speed at this time is obtained from the operating position of the accelerator lever 21 (usually often set to full accelerator), and a predetermined engine speed range to be controlled. Is determined (step # 4). The map data of the engine speed at no load corresponding to the operation position of the accelerator lever 21 is stored in the control device 31 in advance, and the engine speed at no load and the rotation at the maximum horsepower at the operation position of the accelerator lever 21 are stored. From the numbers, an appropriate range of the engine speed that achieves the maximum efficiency (predetermined speed range) is automatically determined.

For example, if the maximum horsepower speed is 2600 rpm when the engine speed at no load due to the operation position of the accelerator lever 21 is 2800 rpm, the upper limit is set to 2620 rpm and the lower limit is set to 2400 rpm. For example, when the engine speed at no load is 2400r
If the maximum horsepower speed at 2 rpm is 2200 rpm, the upper limit is 2220 rpm and the lower limit is 2000 rpm.
It is set to m.

A moving average is obtained by the first calculating means D1 and the second calculating means D2 (steps # 5 and # 6), and the engine speed by the second calculating means D2 and the set operating position of the accelerator lever 21 are determined. The tillage load calculated from the difference from the engine speed at no load is detected in a certain section (step # 7).

When the predetermined rotation speed range is obtained, the mixing control based on the calculation result of the first calculation means D1 is started (step # 8). The mixing control is performed by the automatic raising and lowering control means A and the tillage depth correction control means B, and operates according to the flowchart shown in FIG. Initial setting of the target plowing depth and the engine speed is performed (step # 0).
1) These have already been processed in step # 1.

It is determined whether or not the engine speed is higher than the allowable setting range (step # 02). If it is higher, the target plowing depth is corrected to a deeper side based on fuzzy theory (step # 03). Proceed to step # 06. If it is not high, it is determined whether or not the engine speed is lower than the allowable setting range (step # 04). If it is low, the target plowing depth is corrected to a shallow side based on fuzzy theory ( Step # 05), proceed to step # 06, and proceed to step # 06 even if it is not low and within the allowable setting range. These steps # 02 to # 05 correspond to the operation of the tillage depth correction control means B.

In step # 06, it is determined whether or not the tillage depth is within the set range. If it is within the set range, the process returns to step # 02. If it is outside the set range, it is determined whether or not it is deeper than the target tillage depth. (Step # 07) When the depth is deep, the rotary tilling device 8 is raised (Step # 08). When the depth is not deep (when the depth is shallow), the rotary tilling device 8 is lowered (Step # 09). Return to
These steps # 06 to # 09 are performed by the automatic elevating control means A.
Operation.

In step # 9, it is determined whether or not the engine speed determined by the second calculating means D2 is higher than a predetermined speed range.
The tillage load when raised to the step high-speed
It is predicted from the O shift stage, the engine speed, the traveling shift stage, etc.), and it is determined whether the predicted value is equal to or less than α times the rated load (rated torque) determined by the operation position of the accelerator lever 21 (step # 13). If it is not more than α times, the speed is increased by one step to increase the traveling speed of the body 9 (step # 1).
5) If it exceeds α times, the current gear position is maintained (step # 14), and the process returns to step # 4.

When the determination in step # 9 is NO, the process proceeds to step # 10, in which it is determined whether the engine speed obtained by the second calculating means D2 is lower than a predetermined speed range. Is determined (step # 16). If the vehicle speed has not fallen to the set minimum vehicle speed, the gear stage is shifted by one to increase the torque (step # 12), and the process returns to step # 4. If the set minimum vehicle speed is reached, it is determined whether or not the maximum correction value on the ascending side of the rotary tilling apparatus 8 by the mixing control (the limit correction amount of the tillage depth predetermined in the mixing control) is exceeded (step # 17). If it exceeds, it is no longer possible to recover the engine speed by the mixing control and the vehicle speed control. Therefore, a warning device (not shown) such as a lamp or a buzzer is activated (step # 18). ), Prompt the operator for other measures and return to step # 4. As a countermeasure, it is conceivable to change the PTO gear position and the target plowing depth to the side where the engine load is reduced. If not, it is possible to cope with the mixture control, and the process returns to step # 4.

If the determination in step # 10 is NO, it is determined whether or not the automatic up / down control means A by the highest speed control means F is established (step # 11). Is not satisfied, it is because the traveling speed of the body 9 is high as described above.
Return to 4. Actually, in step # 11, the ratio of the lowering command for a certain time is determined. If the set minimum vehicle speed is determined in step # 16, step # 1
In FIG. 7, the control is performed by the cultivation depth correction control means B (the target cultivation depth is corrected to a shallower side). When the correction value exceeds the limit (in a state where the engine speed is drastically reduced), the initial accelerator lever 21 Since the operation position is low or the target plowing depth is deep, the operator is informed of this by an alarm device.

If there is a margin in the initial setting of the engine speed, the shift speed is increased by the operation of the vehicle speed control means C in a state where the mixing control is operating normally, and the actual traveling speed of the body 9 is reduced. Although the vehicle speed may be higher than the initially set vehicle speed, the running speed of the body 9 may be increased because the efficiency of the tilling operation is improved.
The vehicle speed may exceed the set vehicle speed on the increasing side of the traveling speed. However,
It is determined in step # 11 whether or not the automatic elevating control means A is established in a state where the traveling speed of the machine body 9 is increased, and a countermeasure is taken.

(Ii) When the energy-saving cultivation vehicle speed control mode is selected (FIGS. 7 and 8) The control in the energy-saving cultivation vehicle speed control mode proceeds in the same manner as in the above-described maximum efficiency vehicle speed control mode in the first part. Yes, differences will be described. Step # 1 to Step #
3 and Steps # 5 to # 8 are the same as the maximum efficiency vehicle speed control mode. However, in Step # 20, the target control range (target vehicle speed range) of the traveling speed of the body 9 is used instead of the predetermined rotation speed range. It is different in that it is determined. Hereinafter, step # 21 and subsequent steps will be described.

In step # 21, the load factor (described later) is β
(For example, 0.8), and if it is less than 0.8, the output of the engine 3 has a sufficient margin. The ratio is predicted (step # 25), and if the predicted value is larger than α (for example, 1.1), the shift speed at this time is maintained and the process returns to step # 20. If the predicted value is equal to or less than α, it is determined whether or not the vehicle is at the maximum speed at the set vehicle speed (step # 27). If the vehicle is already at the maximum speed, the process returns to step # 20. Then, the target position of the accelerator (governor 40) is calculated (step # 28). With the gear increased by one gear, the accelerator (governor 4
0) is predicted and calculated (when the load factor is 0.8 or more, 1.
Means for predicting and calculating the position of the accelerator (governor 40) to be 1 or less is also conceivable). The load factor is defined as a value obtained by dividing the load torque by the rated torque at the position of the accelerator (governor 40) at this time.

Whether or not the target position of the accelerator (governor 40) obtained in step # 28 is appropriate is determined from the PTO rotation constraint conditions and the like (step # 29), and if appropriate, the process proceeds to step # 31 to shift. The step is raised by one, and the position of the accelerator (governor 40) is squeezed to the target position of the accelerator (governor 40) obtained in step # 28 (step # 32). If it is not appropriate in step # 29, the accelerator (governor 4
After setting the target position of (0) to the allowable lower limit (the lower limit of the engine speed is predetermined from the minimum tilling pitch), the process proceeds to step # 31 to raise the gear by one step, and the accelerator (governor 40) Is squeezed to the target position of the accelerator (governor 40) obtained in step # 30 (step # 32).

When the determination in step # 21 is NO, the process proceeds to step # 22, in which it is determined whether the load factor is greater than α (1.1). It is determined (step # 33), and when the vehicle speed is the set minimum vehicle speed, the accelerator (governor 40) is opened (step # 34), and then the process returns to step # 20. Control is performed so that the position of the accelerator (governor 40) is opened.
Accelerator (governor 40) when the minimum vehicle speed is not set
Is determined to be fully opened (step # 35). If not fully opened, the target position of the accelerator (governor 40) when the gear is lowered by one gear is calculated (step # 36).
In a state where the shift speed is lowered by one gear, the position of the accelerator (governor 40) is predicted and calculated so as to be within the target vehicle speed range (the accelerator (governor 40) whose load factor is 0.8 or more and 1.1 or less. For example, a means for predicting and calculating the target position may be considered).

Next, the gear is lowered by one gear (step # 3).
7), the position of the accelerator (governor 40) is step # 3
The throttle operation is performed to the target position of the accelerator (governor 40) obtained in step 6 (step # 38), and the process returns to step # 20. If it is determined in step # 35 that the accelerator (governor 40) is fully open, the accelerator position cannot be further opened, and the process immediately proceeds to step # 37 to lower the gear by one step. In step # 38, the accelerator (governor 40) is operated to the target position. In this case, the accelerator (governor 40) remains fully open, and the process returns to step # 20 in this state.

The fact that the load factor is equal to or less than α in step # 22 is an appropriate load factor, and it is determined whether or not the automatic up / down control means A by the highest speed control means F is established (step # 22).
23) If the condition is satisfied, the process directly returns to step # 20. If the condition is not satisfied, the gear is lowered by one (step # 20).
24), and return to step # 20.

As described above, in the maximum efficiency vehicle speed control mode, the engine speed is controlled so as to be maintained in the predetermined speed range determined by the operation position of the accelerator lever 21, and is possible in the predetermined speed range. By maximizing the running speed of the airframe 9, the maximum efficiency of the tilling work is exhibited. In the energy-saving cultivation vehicle speed control mode, the target vehicle speed range is set, and the engine speed (the position of the accelerator (governor 40)) is controlled to the minimum engine speed sufficient to make the traveling speed of the aircraft 9 in the target vehicle speed range appear. By making the intended traveling speed of the aircraft 9 appear at the position of the accelerator (governor 40) which is the minimum necessary, the tilling work can be performed efficiently while saving fuel consumption and noise.

[Alternative Embodiment] The vehicle speed setting unit 29 may be a stepped unit for setting the upper limit and the lower limit of the number of shift stages, or a stepless unit for setting a shift operation region in an HST or a friction type continuously variable transmission. In the vehicle speed control means C using a stepped transmission such as a multi-stage gear shift, operations such as "increase by one step" and "decrease by one step" are performed so that the engine speed falls within a predetermined speed range. In the case of the step-variable transmission, the operations are "increase the predetermined ratio" and "decrease the predetermined ratio". By providing a detent mechanism or the like, even in the case of a continuously variable transmission, an operation of "up one step" or "down one step" is possible.

In the above-described embodiment of the present invention, the tillage depth correction control means B uses the moving average with a small sampling number.
On the basis of the calculating means D1, the vehicle speed control means C is performed based on the second calculating means D2 based on a moving average with a large number of samplings, but the sampling number of the first calculating means D1 is set to 1 (the engine speed is reduced). Based on the raw data of the fluctuation), the tillage depth correction control means B may be performed. Instead of the moving average, the calculation may be performed based on the arithmetic average for each predetermined section sequentially obtained.

For example, the first and second calculation means D1 and D2 are provided only with the first calculation means D1, and data fluctuations which cannot be handled by the vehicle speed control means C are cut off in the control so that hunting or the like can be performed. It is also possible to perform the second operation means D2 without the inconvenience. The rate of change and the amount of change of the raw data of the engine speed are constantly detected, and when the rate of change is gentle below a predetermined value, the vehicle speed control means C is activated. In such a case, means for controlling the tillage depth correction control means B to operate may be used.

Incidentally, reference numerals are written in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

Fig. 1 Side view of a cultivator

FIG. 2 is a block diagram showing a functional system of a tillage control device.

FIG. 3 is a diagram showing a flowchart for selecting a maximum efficiency vehicle speed control mode, an energy-saving cultivation vehicle speed control mode, and a manual operation mode.

FIG. 4 is a diagram showing fluctuations in engine speed;

FIG. 5 is a diagram showing a flowchart of a maximum efficiency vehicle speed control mode.

FIG. 6 is a diagram showing a flowchart of a maximum efficiency vehicle speed control mode.

FIG. 7 is a diagram showing a flowchart of an energy-saving cultivation vehicle speed control mode.

FIG. 8 is a diagram showing a flowchart of an energy-saving cultivation vehicle speed control mode.

FIG. 9 is a diagram showing a flowchart of mixing control (cover MC auto).

[Explanation of symbols]

 Reference Signs List 8 rotary tillage device 9 body 10 elevating drive mechanism 16 rear cover 18 cover sensor 19 tillage depth setting means 20 rotation speed detecting means 24 vehicle speed adjusting means A automatic elevating control means B tillage depth correction control means C vehicle speed control means F maximum speed control means a Transmission for traveling

Claims (4)

[Claims] 1. A rotary tilling device (8) connected to a body (9) so as to be able to drive up and down, and a rear cover that is provided at the rear of the rotary tilling device (8) and that can follow the ground and can swing up and down. (16), a cover sensor (18) for detecting a vertical swing amount of the rear cover (16), and a tillage depth setting unit (19) for setting a target tillage depth of the rotary tiller (8). Automatic elevating and lowering operation of the elevating drive mechanism (10) of the rotary tillage device (8) so that the detection value of the cover sensor (18) matches the target tillage depth set by the tillage depth setting means (19). A control means (A), a rotational speed detecting means (20) for detecting an engine rotational speed,
The traveling speed change device (a) is provided with a vehicle speed adjusting means (24) capable of performing a speed change operation, and when the engine speed becomes lower than a predetermined speed based on the detection of the engine speed, the cultivation depth setting means (19) )
The tillage depth correction control means (B) for changing the target tillage depth set to a shallower side, and the vehicle speed adjusting means (24) when the engine speed becomes lower than a predetermined speed based on the detection of the engine speed. )
And a vehicle speed control means (C) for lowering the running speed of the body (9). 2. When the engine speed becomes higher than a predetermined speed based on the detection of the engine speed, the target plowing depth set by the tillage depth setting means (19) is changed to a deeper side. The tillage control device for a tiller according to claim 1, wherein the tillage depth correction control means (B) is configured. 3. The vehicle speed control according to claim 1, wherein the vehicle speed control means increases the running speed of the vehicle body when the engine speed becomes higher than a predetermined speed based on the detection of the engine speed. The tillage control device for a tiller according to claim 1 or 2, which constitutes the means (C). 4. After the travel speed of the body (9) is changed by the vehicle speed adjusting means (24), if the detected value of the cover sensor (18) does not match the target plowing depth, the body (9) is re-positioned. 4. A vehicle according to claim 1, further comprising a maximum speed control means (F) for linking said vehicle speed control means (C) and said automatic elevating control means (A) so as to reduce a traveling speed. A tillage control device for a tiller according to claim 1.