JPH09107715A - Hydraulic controlling apparatus for working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject apparatus capable of keeping the reaping blade of a combine to a nearly constant height from the ground. SOLUTION: The hydraulic controlling apparatus is provided with a height setting device 41 to set the target height of a divider from the ground, a reaping height sensor to detect the ground height of the divider, a controlling part to calculate the deviation of the real height of the divider from the target height and output a control signal corresponding to the deviation to a lift cylinder and a potentiometer to detect the extent of the vertical motion of the reaping part. The minimum moving amount (H) to enable the recognition of the movement of the reaping part is preset in the controller, driving pulses slowly increasing the pulse width are generated at a definite time interval (Tc ), the driving pulse width (tONU, tOND) for displacing the reaping part beyond the minimum moving amount is calculated as the minimum driving time and the hydraulic pressure is controlled by the calculated driving pulse signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control device for a work vehicle, and more particularly to a hydraulic control device for a work vehicle that controls a work processing unit to set a target height.

[0002]

2. Description of the Related Art In a work vehicle such as a combine harvester, a direction sensor is provided in the lower front portion of the traveling machine body, which operates in contact with the root of a grain culm, for the purpose of unmanned operation, and the grain culm of the direction sensor is used. There is a type in which the side clutch is disengaged / engaged at appropriate times based on the detection signal, whereby the direction of the traveling machine body is automatically corrected to enable continuous work.

That is, in such a combine, based on the detection information from the direction sensor or the like, a pair of left and right traveling devices are driven to automatically perform a turning control in a direction in which the direction of the body is inverted by approximately 180 degrees. As a result, after one mowing process is completed, the machine body can be moved to the next mowing process substantially parallel to the mowing process.

By the way, hydraulic pressure is used for raising and lowering the pretreatment unit for cutting the grain culm and for driving the traveling device, because a large amount of power is required, and furthermore, the cutting blade of the pretreatment unit is kept constant from the ground. In order to maintain the height of the grain culm, the difference between the target height from the ground of the divider that cultivates the culm and the current height is detected,
The control for sending the control signal according to the difference to the hydraulic device is performed.

[0005]

However, the operating characteristics of the hydraulic system change significantly due to the oil temperature, the viscosity of the pressure oil, the manufacturing tolerances of the system, etc., and the conditions change continuously even during continuous operation. However, it is difficult to achieve control matching, which may increase response delay or cause a hunting phenomenon at the time of stop. Therefore, for example, in the case of controlling the height of the divider of the pretreatment unit described above, it is difficult to maintain the divider at the target height.

In order to cope with such a change in the characteristics, it is convenient if the operation characteristics of the apparatus can be checked before each work is started and the control suitable for the characteristics can be performed.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a hydraulic control device for a work vehicle capable of keeping the height of the work processing section from the ground substantially constant. To provide.

[0008]

To achieve this object, the present invention provides a hydraulic drive means (31, 40) for driving a vertically movable work processing unit (11), and the work processing unit (11). Height setting means (41) for setting a target height above the ground, height detecting means (27) for detecting the height of the work processing section (11) above the ground, and the height setting Based on the detection signals from the means (41) and the height detection means (27), a deviation between the target height and the actual height is calculated, and a control signal corresponding to the deviation is calculated, and the hydraulic drive means (31, 40).
And a control means (24) for outputting to the work processing unit (11) for maintaining the height of the work processing unit (11) from the ground substantially constant, in the work processing unit (11). A lift amount detection means (30) for detecting the vertical movement amount of the vehicle is provided, and the control means (24) is also provided.
Is a storage unit (24a) in which a minimum movement amount (H) capable of recognizing the movement of the work processing unit (11) via the lift amount detection means (30) is preset, and a fixed period (T _c ). By generating a drive pulse that gradually lengthens the time,
An operation unit (24b) for calculating a drive pulse width (t _ONU , t _OND ) for the work processing unit (11) to displace the minimum movement amount (H) or more as a minimum drive time;
The hydraulic pressure control is performed based on these calculations.

Preferably, the drive pulse having the minimum drive time is used as a reference pulse, and a plurality of the reference pulses are generated to control the work processing section (H) to move by a predetermined amount.

Further, preferably, the calculation of the minimum drive time is executed while the vehicle is stopped and before the work is started.

(Operation) In the above construction, the present invention has the lift amount detecting means (30) for detecting the amount of vertical movement of the work processing section (11), and the control means ( 24) includes a storage unit (24a) and a calculation unit (2
4b), and the work processing section (1) is stored in the storage section (24a) via the lift amount detecting means (30).
The minimum movement amount (H) capable of recognizing the movement of 1) is set in advance, and in the calculation unit (24b), a drive pulse that gradually increases the time at every constant period (T _c ). By generating the drive pulse width (t _ONU , t _OND ) for the work processing unit (11) to displace the minimum movement amount (H) or more, the drive pulse width (t _ONU , t _OND ) is grasped as the minimum drive time, and the actual hydraulic control thereafter is performed based on the drive pulse signal having the minimum drive time thus obtained.

Note that the reference numerals in parentheses described above are for reference to the drawings, and do not limit the configuration of the present invention at all.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an external perspective view of a combine equipped with a hydraulic control device of the present invention. In FIG. 1, the combine 10 has a driver's seat 26 on the upper part of the machine body 15 and is installed in front of the machine body 15. The cutting unit 11 as a vertically movable work processing unit for cutting the grain culm, the feed chain 12 for sandwiching and transporting the grain culm cut by the reaping unit 11 in a sideways posture, and the feed chain 12
And a threshing unit 13 for accommodating and threshing the grain culm transported by
A pair of left and right crawler traveling devices 1 that support the machine body 15.
4 and 14 are provided.

The crawler traveling devices 14 and 14 are driven via a transmission 20 as a drive unit for changing and transmitting power from the engine, and a rotation speed detection gear 22 is provided coaxially with an output pulley 32 thereof. ing. An electromagnetic pickup 23 is provided in the vicinity of the rotation speed detection gear 22, and the rotation speed of the rotation speed detection gear 22 is detected by the electromagnetic pickup 23 to detect the travel distance of the crawler traveling devices 14, 14. .

In addition, in the front part of the mowing section 11, dividers 16 and 17 for weeding culms, and in the vicinity thereof, a cutting height sensor 2 for detecting the height of the dividers 16 and 17 from the ground.
Besides 7, the left and right direction sensors 18 and 19 are provided to enable automatic steering and cutting while detecting the presence or absence of grain culm. The driver's seat 26 is provided with a height setter 41 for setting a target height of the dividers 16 and 17 above the ground, and solenoid valves 40 and 47 are used to control the raising and lowering of the mowing unit 11, respectively. And steering control by the left and right side clutches. Further, at the center of gravity of the machine body 15, an angular velocity sensor 21 such as a gyroscope for detecting the deviation angle of the machine body 15 and an inclination sensor 28 for detecting the longitudinal inclination of the machine body 15 are provided.

In the above, the height control of the dividers 16 and 17 (that is, the height control of the cutting blade) is performed by detecting signals from the height setter 41 and the cutting height sensor 27 or the inclination sensor 28. The deviation between the target height and the actual height is calculated by the control unit 24 as the control means based on the above, and the solenoid valve 40 as the hydraulic drive means and the lift cylinder 3 to be described later are generated by the control signal according to this deviation.
1 is performed.

Further, the combine 10 is moved to the left and right via the transmission 20 that shifts the crawler traveling devices 14 and 14 based on the detection information from the direction sensors 18 and 19, the angular velocity sensor 21, and the electromagnetic pickup 23 as a distance sensor. By operating the side clutch, the orientation of the machine body 15 is automatically controlled.

In the present invention, the work processing section (1
1) is provided with a lift amount detecting means for detecting the vertical movement amount, and the control means (24) stores a preset minimum movement amount by which the movement of the work processing section (11) can be recognized. Section, and the operation processing section (11) calculates the drive pulse width for displacing the minimum movement amount or more as the minimum drive time.

As shown in FIG. 2, the reaper 11 has
A lift link 29 rotatably connected to the center shaft 42 is attached, and the lift link 29 is rotatable about the center shaft 42 by the operation of a lift cylinder 31. The rotation angle at this time, that is, the amount of vertical movement of the reaper 11 is detected by a potentiometer 30 as a lift amount detecting means.

Further, as shown in FIG. 3, the control section 24 has the cutting height sensor 27 and the potentiometer 3 described above.
0, the inclination sensor 28, and the detection signals from the height setting device 41 are input, and the up / down switch 4 of the mowing unit 11 is input.
3, 44, automatic / manual changeover switch 45, and recognition switch 46 are supplied with signals, and the processing result is output to the solenoid valve 40.

Further, the control section 24 has a storage section 24a in which a minimum movement amount (H) by which the movement of the reaping section 11 can be recognized based on the detection of the potentiometer 30 is preset.
And a drive pulse width (t) for the reaper 11 to displace the minimum moving amount (H) or more by generating a drive pulse that gradually increases the time at every constant period (T _c ).
_ONU , t _OND ) as the minimum drive time
4b.

That is, by examining in advance how much the pulse width of the drive pulse is required to displace the cutting unit 11 by the minimum moving amount (H), it is useful for the actual control thereafter. It is something to try. As the minimum movement amount (H), for example, the minimum observable displacement amount is used.

Thus, before starting the actual work, the control unit 24 recognizes the amount of movement of the reaping unit 11 by a preset signal, and detects the characteristic of the pressure oil (hereinafter, this will be referred to as "hydraulic pressure recognition"). "Control"), in the actual work,
Hydraulic pressure control is performed by sending a signal that matches the characteristics.

Therefore, for example, the minimum drive time (t
It is also possible to perform control such that the reaping unit 11 is moved by a predetermined amount by generating a plurality of reference pulses using a drive pulse having _ONU , t _OND ) as a reference pulse. That is, for example, the reaper 11 is moved to the minimum moving amount H.
_{Assuming that} a drive pulse having a time width t _ONU is required to displace only 10H, it is sufficient to generate 10 drive pulses having a time width t _{ONU in} order to displace the cutting unit 11 by 10H. In this manner, the hydraulic pressure control is performed by generating the pulse according to the displacement amount.

Next, with reference to the control flowcharts of FIGS. 4 and 5, the reaper 11 of the combine 10 is shown.
The hydraulic pressure recognition control will be described.

In FIG. 4, in step S1, it is determined whether or not the machine body 15 is in a stopped state of travel depending on whether the traveling speed change lever is in the neutral position, the vehicle speed sensor is 0, or the like. Then, if the traveling is stopped, the process proceeds to step S2, and if the mowing unit 11 is below the predetermined height, then in step S3, it is determined by the changeover switch 45 whether the work mode is automatic or manual. If it is automatic, it is determined in step S4 whether or not the control step is 0, and if it is 0, the process proceeds to step S10 (FIG. 5). If it is manual in step S3, step S3
5, it is determined whether the recognition switch 46 is ON or not, and if it is ON, the process proceeds to step S10 (FIG. 5).

In step S10, it is determined whether or not the characteristic recognition check on the rising side of the reaping unit 11 is completed. If not completed, the process proceeds to step S11, and if completed, the process proceeds to step S24. That is, the characteristic recognition check on the falling side is performed after the characteristic recognition check on the rising side is completed.

In step S11, it is determined whether or not the timer value for setting the drive pulse generation period T _c has expired. If the timer value has expired, in step S12,
Check the count number of the pulse generation counter. In step S12, when the count number is 0, that is, when it is the first time, in step S13, the initial height H ₀ of the cutting unit 11 is set.
Read and memorize. Further, the pulse generation counter is counted up in step S14, and the timer for the pulse generation period is set in step S15. The pulse generation period T _c is sufficiently long with _respect to the driving time t _ONU and t _OND . Next, in step S16, the driving time t _ONU on the rising side is set. In this case, the pulse generation count value is set to 10 times, and is set according to the cycle timer when the cycle timer ends.

On the other hand, in step S12, when the count number is 1 or more, that is, when the pulse driving for the first time and thereafter is finished and a predetermined time has passed, in step S17, the reaper unit 11 after driving is cut off. The height H ₁ is read, the deviation amount ΔH = H ₁ −H ₀ is calculated, and the current height H ₁ is set as the next initial value. Then, step S1
In step 8, if the deviation amount ΔH is smaller than the recognizable minimum movement amount H, that is, if the movement is not recognized, step S14 is re-executed to obtain the deviation amount ΔH.
If H is larger than the recognizable minimum movement amount H, the process proceeds to step S19. In this step S19, the minimum driving time t _ONU on the rising side is calculated and recognized as 10 times the counter value, and the rising speed V _U of the reaper 11 is ΔH / t.
Calculate _ONU . Furthermore, in step S20, since the minimum drive time t _ONU and the ascending speed V _U can be recognized, the counter is reset and the ascending side processing is ended.

After setting the drive time t _ONU on the rising side in step S16, or in step S11
In step S21, if the period timer has not expired, the drive time t _ONU is checked. If the driving time t _ONU is continuing, the rising side output signal is generated in step S22, and if it is completed, the output is output in step S23. Stop. Next, when the process on the ascending side is completed, the process proceeds to the process on the descending side, and the same processes as those on the ascending side are performed from steps S24 to S37.

However, in the arithmetic expression for obtaining the deviation amount ΔH in step S31, when the cutting unit 11 descends, the current height H ₁ after movement becomes smaller than the initial height H ₀ ,
The difference is that ΔH = H ₀ −H ₁ .

FIGS. 6A, 6B, and 6C are time charts showing the operation in the control flowchart.

That is, on the ascending side, FIG.
In (c) and (c), the timer with the cycle T _c sets 1 from the ascending side.
The pulse width is fixedly lengthened once, twice, and three times, and the output change ΔH of the potentiometer 30 is compared with the minimum movement amount H. As a result, ΔH <H up to the third time, but when the fourth pulse is output, ΔH> H, so the value of the counter is multiplied by 10, and the minimum drive time t _ONU on the rising side and the drive speed V are increased. Obtain _U and end the process on the ascending side.

Similarly, as for the descending side, in FIGS. 6B and 6C, ΔH> H at the second pulse output, so that the minimum driving time t _OND and the driving speed V _D on the descending side are obtained. Then, the processing on the descending side is completed.

Next, the operation of the present embodiment will be described.

The hydraulic pressure recognition control of the combine 10 is performed when the crawler traveling device is stopped before starting the work.
First, when performing the recognition control, the operator operates the automatic / manual changeover switch 45 provided in the driver's seat 26 to select the work mode. And
When the automatic mode is selected, the process on the ascending side of the mowing unit 11 is executed and the process on the descending side is subsequently executed according to a predetermined program. Therefore, the operator does not need to do anything other than operate the selection switch, and the control unit 24 automatically performs the processing.

On the other hand, when the manual mode is selected, the recognition switch 46 is subsequently turned on, and the raising switch 43 provided in the driver's seat 26 is turned on. As a result, the process on the ascending side of the reaper 11 is executed according to the predetermined program. When the process on the ascending side is completed, next, the descending switch 44 is turned on. As a result, according to a predetermined program, the reaper 1
The processing on the descending side of 1 is executed.

When the hydraulic pressure recognition control is completed as described above, a signal suitable for the hydraulic pressure characteristic at that time is output from the control unit 24 to the hydraulic drive unit.
Appropriate hydraulic pressure control is performed. Therefore, after the recognition control is completed, if the mowing work or the like is performed, the height positions of the ground and the cutting blade are kept substantially constant, and the good mowing work can be performed.

[0040]

As described above, according to the present invention, the minimum drive time is calculated based on the drive pulse when the work processing section makes a predetermined displacement, and the drive pulse signal thus obtained is used for the control during work. Since it is used, the drive pulse signal includes control constants to which various conditions are added, and therefore the control matching property is good, and there is no risk of response delay or hunting. The height from the ground can be kept substantially constant.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a combine to which a hydraulic control device according to the present invention is applied.

FIG. 2 is a view showing a lift link mechanism of a mowing section.

FIG. 3 is a diagram showing a control system configuration according to the present embodiment.

FIG. 4 is a diagram showing a flowchart in hydraulic pressure recognition control.

FIG. 5 is a diagram showing a flowchart in hydraulic pressure recognition control.

6A and 6B are diagrams showing an operation time chart in the hydraulic pressure recognition control, wherein FIG. 6A is a diagram showing a drive pulse at the time of rising and its generation period, and FIG. 6B is a drive pulse at the time of falling and its generation period. FIG. 4C is a diagram showing potentiometer output.

[Explanation of symbols]

 10 Combine 11 Mowing Section 14 Crawler Traveling Device 15 Aircraft 16 Divider (Left) 17 Divider (Right) 18 Direction Sensor (Left) 19 Direction Sensor (Right) 24 Control Section 24a Storage Section 24b Computing Section 26 Driver's Seat 27 Cutting Height Sensor 29 Lift link 30 Potentiometer 31 Lift cylinder 40 Solenoid valve 41 Height setting device 43 Up switch 44 Down switch 45 Automatic / manual switch 46 Recognition switch

Claims (3)

[Claims] 1. A hydraulic drive unit for driving a vertically movable work processing unit, a height setting unit for setting a target height of the work processing unit above the ground, and a height setting unit of the work processing unit above the ground. Height detection means for detecting the height, based on the detection signals from the height setting means and the height detection means, calculates the deviation between the target height and the actual height, and the control signal corresponding to the deviation is used as the hydraulic pressure. A hydraulic control device for a work vehicle for maintaining the height of the work processing unit from the ground substantially constant, the control unit outputting the work processing unit to a drive unit; and detecting a vertical movement amount of the work processing unit. With the lift amount detecting means for, the control means, the storage unit in which the minimum movement amount that can recognize the movement of the work processing unit through the lift amount detecting means is set in advance, and gradually at regular intervals. Drive pulse that lengthens time And a calculation unit that calculates the driving pulse width for displacing the minimum movement amount or more by the work processing unit as the minimum driving time, and hydraulic control is performed based on these calculations. A hydraulic control device for a work vehicle, comprising: 2. The drive pulse having the minimum drive time is used as a reference pulse, and a plurality of the reference pulses are generated to control the work processing unit to move by a predetermined amount. A hydraulic control device for a work vehicle according to claim 1. 3. The hydraulic control device for a work vehicle according to claim 1, wherein the calculation of the minimum drive time is executed while the vehicle is stopped and before the work is started.