JPH0837866A - Vertical motion controlling apparatus for working machine - Google Patents

Abstract

PURPOSE:To provide a vertical motion controlling apparatus for working machine capable of keeping a cutting height in an adequate level even in the case where a detecting means for the height from the ground enters into standing culms. CONSTITUTION:The working vehicle is provided with a controlling apparatus 12 for a hydraulic cylinder CY which drives a vertical motion so that the height of a cutting member 2 from the ground is adjusted to a predetermined height based on information obtained by a height detection means S1 for detecting a cutting height from the ground. The working vehicle is also provided with a stock-division detection means 100 for detecting that the height detection means S1 has intruded into standing culms, in other words, a stockdividing state. When the stock-dividing state detection means 100 detected the stock- dividing state, the controlling mode 12 is shifted from the ordinary vertical motion-controlling mode to a stock-dividing state-controlling mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elevating control device for a working vehicle such as a combine, and more specifically, an actuator for elevating and lowering a mowing section for mowing planted stem culms, and a ground height of the mowing section. Ground height detecting means for detecting, and based on the detection information of the ground height detecting means, the elevation control means for controlling the actuator, so that the ground height of the reaper is a target height. Lifting control device for work vehicle.

[0002]

2. Description of the Related Art Conventionally, in a lift control device for a work vehicle, a ground height of a mowing section detected by the ground height detecting means is a target while the lift control means is executing the lift control. The actuator is controlled so that the height is set, and the height-to-ground detecting means is arranged so as to be located between the planting lines of the planting stems. .

[0003]

[Problems to be Solved by the Invention] While the work vehicle is running along the rows between the rows of the planting stems,
Although proper lifting control is executed, in this type of work vehicle, for example, the traveling device of the work vehicle slips between itself and the ground, or the direction of travel is reduced due to an operator's operation error, etc. May shift from a predetermined direction, but in such a case, the ground height detecting means is rushed into the planted stem culm, not a separation distance from the ground, but with a bent stem culm. In some cases, the distance between them may be detected.

As a result, in the above conventional structure, by detecting the distance between the stem and the stem as described above,
Even if the detected height to ground becomes a relatively low value and the distance from the ground is maintained at substantially the target height, the raising / lowering control means relatively raises the cutting unit. It will be. Then, there is a disadvantage that the height of the mowing work becomes higher than the target height, and there is room for improvement in this respect.

The present invention has been made by paying attention to such a point, and an object of the present invention is to reduce the height of the cutting work even if the ground height detecting means rushes into the planting culm. The purpose of the present invention is to provide a lifting / lowering control device for a work vehicle, which can maintain the workability at an appropriate level.

[0006]

The features of the first invention are as follows:
An actuator for moving up and down the mowing unit for mowing the planted culm, a ground height detecting unit for detecting the ground height of the mowing unit, and the ground information of the mowing unit based on the detection information of the ground height detecting unit. An elevation control device for a work vehicle, comprising elevation control means for controlling the actuator so that the height becomes a target height, and the ground height detection means detects the ground height based on the detection information of the ground height detection means. The means is provided with a stock splitting state determining means for determining that the stock splitting state is in the planting culm, and the lifting control means is configured such that the stock splitting state determination means is in the stock splitting state. It is configured to switch the control mode from the normal lifting control mode to the stock splitting state control mode in accordance with the determination.

A characteristic configuration of the second invention is to specify a configuration suitable for carrying out the first invention, wherein the ground-height detecting means is arranged for each set unit time or set unit traveled distance.
It is configured to perform a detection operation, the stock splitting state determination means, within a set time, or while traveling a set distance, of abnormal data for all the detection data detected by the ground height detection means. When the ratio exceeds the set amount, it is configured to determine that the stock is in the split state.

A characteristic structure of the third invention is to specify a structure suitable for carrying out the first invention, in which the ground height detecting means is set for each set unit time or set unit traveled distance.
Is configured to perform a detection operation, the stock splitting state determination means, within a set time, or while traveling a set distance, the average value of a plurality of detection values detected by the ground height detection means The point is that it is configured to determine the discrete value of each of the detected values with respect to the average value, and determine the stock split state based on the discrete value.

A characteristic configuration of the fourth invention is to specify a configuration suitable for carrying out the first, second or third invention, and in the elevating control means, the stock split state determination means is used for the stock split. Along with determining that the state is in a state, the actuator is controlled in the stock split state control mode in which the ascending side control output of the mowing unit is switched from the high speed side to the low speed side. It is in.

The characteristic features of the fifth invention are: the first, second, and third.
Alternatively, the configuration suitable for carrying out the fourth aspect of the invention is specified, wherein the elevating / lowering control unit determines whether the detected value of the ground height detecting unit and the ground height of the mowing unit are in the normal elevating / lowering control mode. The larger the deviation from the target value, the larger the speed at which the actuator is controlled to execute the raising / lowering operation. When the stock splitting state determination means determines that the stock splitting state is present, the actuator Is configured to control the actuator in the stock splitting state control mode in which the maximum control output on the rising side is switched to the low speed side.

According to a sixth aspect of the present invention, a configuration suitable for carrying out the first, second or third aspect of the present invention is specified. It is configured such that the ascending operation output of the actuator is stopped in accordance with the determination of the state.

[0012]

According to the characterizing feature of the first invention, based on the detection information of the ground height detecting means, it is determined whether or not the ground height detecting means is in the stock splitting state in which the ground height detecting means is thrust into the planting culm. If it is determined that the stock is in the stock split state, the lift control is executed in a state where the control mode is switched from the normal lift control mode to the stock split state control mode. In the stock splitting state control mode, for example, the raising operation by the actuator is stopped, or the raising speed is made slower than the set speed, or the cutting portion is detected from the average value of the detection values by the ground height detecting means. When calculating the height above ground, increase the average number of data, etc.
It is possible to maintain an appropriate up-and-down state in response to the stock splitting state, such as suppressing the sensitive upward movement of the actuator.

According to the characterizing structure of the second invention, there is the following function in addition to the function of the characterizing structure of the first invention. The ground-height detecting means detects the ground-height of the mowing unit for each set unit time or each set unit travel distance. Then, if the ratio of abnormal data to all the detection data detected by the ground height detecting means exceeds the set amount within the set time or while traveling the set distance, it is determined that the stock split state. is there.

That is, during a normal mowing operation that is not in the stock splitting state, the ground height detecting means appropriately detects the distance from the ground, and when the stock splitting state occurs,
Since a detection value greatly different from the detection height up to that point is detected, it is possible to determine whether or not there is an abnormality by comparing it with past detection data. Further, due to the detection characteristics of the ground height detection means, when the detection target distance is a value smaller than the minimum detectable distance, if an abnormal value is detected, such a detection value itself may be used. Whether or not it is abnormal can be determined.

According to the characterizing structure of the third invention, the following function is provided in addition to the function of the characterizing structure of the first invention. The ground-height detecting means detects the ground-height of the mowing unit for each set unit time or each set unit travel distance. Then, within a set time, or while traveling a set distance, obtain an average value of a plurality of detection values detected by the ground height detection means, and obtain the discrete value of each detection value with respect to this average value, Based on this discrete value, the stock split state is determined.

In other words, when the stock split condition is occurring,
The ground height detecting means detects the distance to the stalks that are bent on the lower side, but since the stalks are a set of thin stalks, there is a large difference locally from the average value data. May be detected. Therefore, by obtaining the discrete value of each detected value with respect to the average value, it is possible to determine that the abnormal value is detected by the stock split in this way.

According to the characteristic configuration of the fourth invention, the first and second aspects are provided.
Alternatively, the following operation is provided in addition to the operation according to the characteristic configuration of the third invention. When it is determined that the plant is in the stock splitting state, the actuator is controlled in a state in which the control output on the rising side of the cutting unit is switched from the high speed side to the low speed side. As a result, due to the occurrence of the stock splitting condition, even if it is determined that the detection ground height of the mowing unit by the ground height detecting means has a relatively low value, Ascending operation will be executed at low speed, for example, avoiding the disadvantage that the height of the mowing section above the ground greatly deviates from the target height because the actuator operates at high speed until the stock split condition is resolved. it can.

According to the characterizing feature of the fifth invention, there is the following effect in addition to the effect of the characterizing feature of the first, second, third or fourth invention. In the normal raising / lowering control mode, the larger the deviation between the detection value of the ground height detecting means and the target value of the ground height of the mowing unit, the larger the speed at which the actuator controls to perform the raising / lowering operation. Therefore, for example, when the ground is largely raised, the raising and lowering operation is executed at high speed, it is possible to avoid the rushing of the mowing part to the ground, and it is possible to move up and down at a low speed for small unevenness. Therefore, it is possible to avoid performing high-speed and frequent lifting operations.

When it is determined that the stock is in the stock split state, the actuator is controlled in the stock split status control mode in which the maximum control output on the rising side to the actuator is switched to the low speed side. Therefore, for example, it is possible to avoid the disadvantage that the actuator operates at a high speed until the stock splitting state is resolved, and the ground height of the mowing unit largely deviates from the target height.

According to the characteristic constitution of the sixth invention, the first and second
Alternatively, the following operation is provided in addition to the operation according to the characteristic configuration of the third invention. When it is determined that the plant is in a plant splitting state, the output for raising the actuator is stopped, so the ground level of the mowing section is determined by the ground level detecting means plunging into the planting culm. It will be maintained at the same height as before.

Therefore, it is possible to avoid the disadvantage that the ground height greatly deviates from the target height due to the unnecessary raising operation of the reaper.

[0022]

According to the characterizing feature of the first invention, when the stock splitting state is determined, by switching the control mode in the lifting control, it is possible to maintain the proper lifting state corresponding to the stock splitting state. It is possible to avoid the disadvantage that the height of the mowing unit above the ground greatly deviates from the target height.

According to the characterizing structure of the second invention, the following effect is obtained in addition to the effect of the characterizing structure of the first invention. Effectively utilizing the detection information of the height-to-ground detecting means and determining that the stock is in the stock split state based on the detection information, it is not necessary to provide a dedicated sensor for the stock split status detection, It is possible to detect the stock splitting state without causing complication.

According to the characterizing structure of the third invention, the following effect is obtained in addition to the effect of the characterizing structure of the first or second invention.
By rational processing of the detection information of the ground height detection means,
It is possible to accurately judge that the stem culm, which is a collection of thin stems, is in the state of splitting the stock existing below the ground height detecting means.

According to the characteristic constitution of the fourth invention, the first and second
Alternatively, there are the following effects in addition to the effects of the characteristic configuration of the third invention. It is possible to avoid the disadvantage that the height of the mowing unit above ground greatly deviates from the target height, and it is possible to maintain the mowing unit at the target height as much as possible.

According to the characterizing feature of the fifth invention, the following effect is obtained in addition to the effect of the characterizing feature of the first, second, third or fourth invention. In the normal lifting control mode, it is possible to perform smooth lifting control while avoiding the rushing of the mowing unit to the ground, while maintaining the mowing unit at the target height as much as possible in the stock splitting state. It becomes possible.

According to the characteristic configuration of the sixth invention, the first and second
Alternatively, there are the following effects in addition to the effects of the characteristic configuration of the third invention. When the stock splitting state occurs, it is possible to suppress the unnecessary raising operation of the cutting unit and maintain the ground height at the target height.

[0028]

Embodiments will be described below with reference to the drawings. Figure 7
The front part of the combine as an example of the work vehicle is shown in FIG. This combine is configured to be able to travel by including a pair of left and right crawler traveling devices 1 and 1, and a cutting pretreatment unit as a working device for cutting planted grain culms (an example of planted stem culms) in the front part of the machine body. 2 is provided so as to be able to move up and down, and a rear side is provided with a threshing device 3 for threshing the cut culms, a grain tank 4 for storing the threshed grains, a boarding operation unit 5, and the like.

The pre-cutting processing section 2 includes a weeding tool 6 for allocating and dividing the planted culms of the line to be trimmed, a raising device 7 for raising the planted culms in a standing posture, and a plant of the raised culms. Hair clipper type cutting device 8 for cutting the original side, vertical transfer device 9 for transferring the cut grain culm backward while gradually changing its posture to a sideways posture.
Etc., and is pivotally supported so as to be able to move up and down around a horizontal axis with respect to the machine body. Further, the hydraulic cylinder CY as an actuator is configured to be driven up and down by an expansion / contraction operation.

A work for determining whether or not the pre-mowing processing unit 2 is in the mowing work state by detecting whether or not a mowing grain culm is present at the carrying entrance of the vertical carrying device 9. The stock origin sensor S0 which is a state determination means is provided.
Further, an ultrasonic sensor S1 as a ground height detecting means for detecting the ground height is provided at a position on the rear side of the weeding tool 6. This ultrasonic sensor S1 is composed of a transmitter 10 for transmitting ultrasonic waves downward and a receiver 11 for receiving ultrasonic waves reflected on the ground, and the time from transmission to reception It is configured in a non-contact manner so as to detect the height above ground by measuring. To add an explanation,
In determining the reception of ultrasonic waves, it is determined that "reception" is performed on condition that the reception intensity is higher than the set intensity, and the receiver 11 directly transmits from the transmitter 10. For the purpose of avoiding erroneous detection due to reception of waves, the set strength is configured to gradually decrease with the lapse of time after transmission. Therefore, in the present ultrasonic sensor S1, when the reflected object of the ultrasonic wave is distant or extremely close, it is not judged to be received, and the detected data has a large value close to the maximum value.

As shown in FIG. 1, the hydraulic cylinder CY.
Is a single-acting type cylinder, and the hydraulic oil CY supply state is changed to a rising position (ON
State), a neutral stop position (OFF state), and a supply position to the hydraulic device for the others, and a three-position switching type electromagnetic rising control valve V1 is provided.
1 is configured to be switched and controlled by a control device 12 as an elevating control means.

Further, the pair of drain oil passages L2, L3 branched in parallel from the middle of the pressure oil supply passage L1 for the hydraulic cylinder CY have orifices 13, 13 having different throttle diameters.
14 is provided, and each of the drain oil passages L2 and L3 is provided with two-position switching type open / close lowering control valves V2 and V3.

The boarding operation unit 5 has a mowing height setting device 15 for setting the set height of the mowing pretreatment unit 2 during mowing work.
And an elevating lever 16 for elevating and lowering the pre-mowing processing unit 2 based on manual operation. When the elevating lever 16 is operated from the neutral position to the ascending position, the ascending switch SW1 is turned on and operated to the descending position. Then the lowering switch S
W2 is turned on and each switch SW1, S
The detection state of W2 is input to the control device 12. Further, the detection state of the stock source switch S0 is also input to the control device 12. Although not illustrated, the pre-mowing processing unit 2
There is provided height-to-body detecting means for detecting the height with respect to the body. Further, the traveling drive system for the crawler traveling device 1 is provided with a revolution speed sensor S2 for detecting the revolution speed of the traveling output shaft, and the control device 12 is based on this revolution speed information.
The present traveling speed and traveling distance are calculated. Therefore, the rotation speed sensor S2 constitutes the vehicle speed detecting means of the vehicle body.

The control device 12 automatically turns on and off on the condition that the height of the pre-mowing processing unit 2 is lower than the set height based on the information of the height detecting means for the body. With the ON operation of the switch SW3, the automatic raising / lowering control for controlling the operation of the hydraulic cylinder CY is performed so that the ground height of the pre-mowing processing unit 2 becomes a set value. And at the beginning and end of the mowing work,
Even when the automatic raising / lowering control is performed to raise / lower the reaping pretreatment unit 2 based on the command of the lifting / lowering lever 16, if the command of the lifting / lowering lever 16 is issued, the manual lifting / lowering operation based on the command of the lifting / lowering lever 16 is performed. It is configured to be executed prior to the automatic lifting control. Incidentally, the raising / lowering operation by the raising / lowering lever 16 is executed by "high speed ascent" and "high speed lowering" which will be described later.

Then, the controller 12 controls the stock origin sensor S0.
Is in the OFF state (non-working state), and OFF
While the set time (4 seconds) elapses from the time when the switch from the state to the ON state (working state) is detected,
The control sensitivity of the lifting control operation based on the detection information of the ultrasonic sensor S1 is sensitively changed and set, and the set time (4 seconds) starts from the time when it is detected that the stock sensor S0 is switched from the OFF state to the ON state. After the lapse of time, the control sensitivity of the lifting control operation is set to be insensitive.

Further, based on the detection information of the ultrasonic sensor S1, the stock splitting state judging means 100 for judging that the ultrasonic sensor S1 is in the stock splitting state in which it has entered the planting culm is in a control program format. Equipped with the stock split status determination means 1
00 is configured to control the hydraulic cylinder CY in a state where the normal lift control mode is switched to the stock split control mode when it is determined that the stock split state is set.

The control operation of the controller 12 will be described in detail below with reference to the control flowcharts of FIGS.
If the automatic on / off switch SW3 is turned on and the automatic raising / lowering control is activated, if the stock origin sensor S0 is in the off state, 4 seconds elapse after switching from the off state to the on state even in the on state. If not, the vehicle speed is 0.2
If the speed is less than or equal to meters / second (step 1 to
4) The control sensitivity of the lifting control operation is sensitively changed and set.

That is, the controller 12 controls the ultrasonic sensor S
In step 1, if ultrasonic waves are transmitted every 20 msec and the ultrasonic sensor S1 receives the reflected waves, that is, if the measurement operation is completed, the time from the transmission to the reception is converted into ground height data. Convert (steps 5 and 6). If the detected ground height data is a value of 1500 mm or more, it is determined to be an abnormal value and error processing is executed. If it is 1500 mm or less, the data is stored in the memory (step 7).
~ 9). At this time, if it is abnormal, the counter is incremented.

Thus, the detected ground height data is 1500
If the value is greater than or equal to mm, it is determined to be an abnormal value.
If the measurement distance (distance from the ground) of the ultrasonic sensor S1 is less than or equal to a set value, measurement becomes impossible due to its characteristics.
Although the reflected wave cannot be properly received and the detection distance becomes a large value close to the upper limit value on the contrary, it does not become such a large value during the mowing operation, and is therefore treated as an abnormal value.

Then, every time the past five data are stored, an average value of them is obtained, and the average value is used as the detected ground height data, and the output process for the hydraulic cylinder CY is executed (steps 10 and 11). In this mean value calculation process, if the number of data does not reach 5, the process returns. In this way, the average value of the five detection values is calculated about every 100 msec, and the elevation control is executed sensitively based on this average value.

When the stock sensor S0 is switched from the OFF state to the ON state and 4 seconds have passed and the vehicle speed is 0.2 m / sec or more (steps 1 to 4), the elevator is moved up and down. The control sensitivity of the control operation is set to be insensitive. That is, the ultrasonic sensor S1
At 20 msec, an ultrasonic wave is transmitted, and if the ultrasonic sensor S1 receives a reflected wave, the time from the transmission to the reception is converted into ground height data (step 1
2, 13). If the detected ground height data is a value of 1500 mm or more, it is determined to be an abnormal value and error processing is executed. If it is 1500 mm or less, the data is stored in the memory (steps 14 to 16). If there is an abnormality at this time, the counter is incremented.

If the detected height to ground data is a value of 1500 mm or more, it is determined that the value is an abnormal value if the distance to be detected by the ultrasonic sensor S1 is smaller than the minimum detectable value. Becomes impossible, and as a result, the detected ground height becomes a very large value, so in such a case,
It is treated as abnormal data.

After that, every time the traveling distance reaches 5 cm, 5
Find the first average value of the data during the cm travel (step 1
7, 18). The number of data n is the maximum number of memory buffers n
_When it becomes ₀ , the process returns to avoid overflow (step 19).

Then, every time the vehicle travels 30 cm, the average value (second average value) of the remaining data excluding the maximum value and the minimum value is obtained from the data obtained every 5 cm travel (step 20). If the second average value H ₂ is larger than the previous second average value data H ₁ by 100 mm or more, it is determined that the data is abnormal data, and the abnormality processing is performed (steps 21 and 22).
When the difference between the second average value H _{2 and the} previous second average value data H ₁ is not larger than 100 mm, the output process is executed with the second average value H ₂ as the detected ground height data (step 23, 24).

Next, the output process will be described. As shown in FIG. 4, a deviation between the ground height data obtained as described above and the target height set by the cutting height setting unit 15 is obtained (step 25), and the deviation falls within the dead zone. For example, based on the magnitude of the deviation, the operating condition of the hydraulic cylinder CY is determined so that the operating speed increases as the deviation increases (steps 26 and 27).

That is, as shown in FIGS. 5 and 6, the descending speed and the ascending speed can be switched in three stages, respectively, according to the switching condition of the descending control valves V2, V3 based on the magnitude of the deviation. It has become. In addition, V2 is a down control valve with a large throttle diameter (small flow rate), V3 is a down control valve with a small throttle diameter (large flow rate), and in FIG. 5 (duty), the down control valve is intermittently turned on. / OFF operation, specifically, in "low speed descent", the descent control valve V3 is 15 msec.
It is set to alternately turn ON and 40 msec OFF, and in the "medium speed rise", the lowering control valve V2 is set to 35 mse.
It is set to alternately repeat cON and 20 msec OFF.

If the operating condition is "high speed rise", if the abnormal value data counted in the steps 8 and 15 is 50% or more during the traveling of the vehicle body for 1 m, the ultrasonic sensor is used. It is determined that S1 is a stock splitting state in which the planted grain culm is plunging, and "1" is set in the flag (steps 28, 29, 30). If the flag is "1", the rising control valve V1 is set to, for example, 0.2.
The hydraulic cylinder CY is operated in a state in which it is intermittently switched to ON for 0.8 seconds and OFF for 0.8 seconds to reduce the rising speed (steps 33, 3).
4).

Then, if the operating condition is other than "high speed increase", or if the ratio of the abnormal data is 20% or less, even if the operating condition is "high speed increase", it is determined that the stock split state has been eliminated. Reset the flag to "0",
The hydraulic cylinder CY is operated under the operating conditions determined in step 27 (steps 31, 32, 33, 3).
5). At this time, if the operating condition is "high speed rise",
The rising control valve V1 is maintained at "ON", and the continuous rising operation at high speed is executed.

In the operation in the direction in which the deviation decreases with the operation of the hydraulic cylinder CY, even when the deviation is within the dead zone, it is necessary to set it within a set width narrower than the dead zone. (See FIGS. 5 and 6) The output operation continues (step 36). Then, after the output operation is once stopped within the set width and the output operation is stopped, the output start condition is that the deviation exceeds the dead zone.

As described above, when the stock splitting state is determined, the operating speed of the hydraulic cylinder CY is switched to the low speed side to suppress the unnecessary lifting operation, and the ground level of the mowing unit 2 is set to the target as much as possible. Can be maintained at height.

[Other Embodiments] (1) In the above embodiment, in the stock split control mode,
Although the maximum output of the hydraulic cylinder (actuator) on the rising side is switched to the low speed side, the speed on the rising side of the hydraulic cylinder may be switched to the low speed side over the entire range of speed change. (2) In the above embodiment, in the normal lifting control mode,
Although the control is performed so that the hydraulic cylinder operates at a higher speed as the deviation increases, the operation speed of the hydraulic cylinder may be constant regardless of the deviation. In the control mode, the operating speed may be switched to the low speed side. (3) In the above-described embodiment, when the stock splitting state is determined, the determination is made based on the ratio of the abnormal value of the ultrasonic sensor during traveling the set distance, but instead of this,
Obtain a plurality of average values of the detection value of the ultrasonic sensor, obtain the discrete value of this average value and each detection value, from the information of this discrete value, for example, using a statistical method, the stock split state You may make it discriminate. (4) In the above embodiment, the detection operation by the ultrasonic sensor is executed every set unit time, but it may be detected every time the work vehicle travels the set unit distance. (5) In the above-described embodiment, in the stock split control mode, the hydraulic cylinder is operated to move upward while the operating speed is switched to the low speed side. However, when the stock split state is determined, after that point, The raising operation output may be stopped so as to suppress an unnecessary raising operation of the mowing unit. (6) In the above-described embodiment, the hydraulic cylinder is used as the actuator, but instead of this, for example, an electric motor, a screw feed mechanism, and other actuators outside the hydraulic cylinder may be used to move the cutting unit up and down. (7) In the above embodiment, the ultrasonic sensor is used as the ground height detecting means, but instead of this, an electromagnetic wave or light may be projected to detect the ground height by the reflection state from the ground. Various height-to-ground detecting means such as a configuration in which a potentiometer detects the amount of vertical swing of the grounding body, which vertically swings to follow the ground, can be used.

It should be noted that reference numerals are added to the claims for facilitating the comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a control block diagram.

[Fig. 2] Control flowchart

FIG. 3 is a control flowchart.

FIG. 4 is a control flowchart.

FIG. 5 is a diagram showing an output processing state.

FIG. 6 is a diagram showing an output processing state with respect to a ground distance.

FIG. 7 is a side view of the front part of the combine.

[Explanation of symbols]

 2 Mowing unit 12 Elevating control means 100 Stock splitting state determination means CY Actuator S1 Ground height detection means

Claims (6)

[Claims] 1. An actuator (CY) for moving up and down a mowing unit (2) for mowing the planted stems, a ground height detecting means (S1) for detecting a ground height of the mowing unit (2), Based on the detection information of the ground height detecting means (S1),
So that the height of the reaper (2) above ground is the target height,
A lift control device for a work vehicle, comprising: a lift control means (12) for controlling the actuator (CY), based on detection information of the ground height detection means (S1),
The ground height detecting means (S1) is provided with a stock splitting state determination means (100) for determining that the stock splitting state is in a state of plunging into the planted stem culm, and the elevation control means (12) is Lifting of a work vehicle configured to switch the control mode from the normal lifting control mode to the stock splitting state control mode when the stock splitting state determination means (100) determines that the stock splitting state is set. Control device. 2. The ground height detection means (S1) is configured to execute a detection operation for each set unit time or set unit travel distance, and the stock splitting state determination means (100) is set for a set time. If the ratio of the abnormal data to all the detection data detected by the ground height detecting means (S1) exceeds the set amount while the vehicle is traveling inside or within the set distance, it is determined that the stock splitting state is set. The lifting control device for a work vehicle according to claim 1, wherein the lifting control device is for a work vehicle. 3. The ground height detection means (S1) is configured to execute a detection operation for each set unit time or each set unit travel distance, and the stock splitting state determination means (100) sets a set time. Inside, or while traveling a set distance, the average value of the plurality of detection values detected by the ground height detecting means (S1) is obtained, and the discrete value of each detection value with respect to this average value is obtained. The elevator control device for a work vehicle according to claim 1, wherein the elevator control device is configured to determine that the stock split state is set based on the discrete value. 4. The ascending / descending control means (12) raises the control output of the reaping section (2) when the stock splitting state determination means (100) determines that the stock splitting state is in the stock splitting state. The elevator control device for a work vehicle according to claim 1, 2 or 3, wherein the actuator (CY) is controlled in the stock splitting state control mode in which the high speed side is switched to the low speed side. 5. The raising / lowering control means (12) sets the detection value of the ground height detecting means (S1) and the target value of the ground height of the reaper (2) in the normal raising / lowering control mode. The larger the deviation, the higher the speed at which the actuator (CY) is configured to control to perform the raising / lowering operation, and when the stock splitting state determination means (100) determines that the stock splitting state is set, The actuator (CY) is configured to be controlled in the stock splitting state control mode in which the maximum control output on the rising side to the actuator (CY) is switched to a low speed side. Four
Lifting control device for the work vehicle described. 6. The actuator (C) when the lift control means (12) determines that the stock split state determination means (100) is in the stock split state.
The lifting control device for a work vehicle according to claim 1, 2 or 3, which is configured to stop the output for lifting operation of Y).