JP3121004B2 - Power detector for working unit in harvester - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting power consumption of a working unit in a harvester such as a thresholder or a combine for harvesting rice, wheat, soybeans, and the like. .

[Conventional technology]

In harvesters such as thresholders and combiners equipped with a pre-cutting device in front of a traveling machine equipped with a processing unit for threshing, etc., power from one engine such as a gasoline engine or diesel engine mounted on the traveling machine Are transmitted to the traveling drive unit, the pre-cutting device, and the working unit for threshing, etc., so that predetermined work is performed at each location.

In this case, since the vehicle travels at a low speed with a large traveling load during wetland traveling, the harvesting speed is low and the load on the threshing unit is not very large. Conversely, when harvesting the rain-grained culm in the dry field, even if the running load is not so large, the load on the running section changes such that the load on the threshing section increases due to threshing of the rain-grained culm, It does not always link with the fluctuation of the load of the working unit.

Therefore, as disclosed in Japanese Patent Publication No. 2-2573 of the prior art, the power from the engine is transmitted to the traveling unit via the hydraulic drive means capable of performing shift control, while the power from the engine is transmitted in parallel with the hydraulic drive means. In many cases, the power from the engine is transmitted to the working unit, and the shift operation between the traveling unit and the working unit is often performed in different systems.

Fuel supply to the engine is also performed in order to increase or decrease the shaft output (power) of the engine in accordance with the load caused by the running resistance of the running section or the load caused by the increase or decrease of the amount of the workpiece in the working section such as threshing. It is general to adjust so as to increase or decrease the amount, in which case, there is a need to optimally maintain the working efficiency of the cutting pretreatment device and the handling cylinder of the threshing unit,
Normally, the rotation speed of the working unit is set based on the rated rotation speed of the engine, and therefore, in the harvesting state of the harvester, regardless of the magnitude of the load on the engine, It is preferable to control the engine to operate near the rotational speed.

As the prior art, the present applicant has previously disclosed Japanese Patent Application Laid-Open No. 63-10 / 1988.
In Japanese Patent No. 2614 and Japanese Patent Application Laid-Open No. Sho 64-47312, the engine for driving the traveling section of the harvester and the working section such as the mowing section and the threshing section is controlled at the rated speed (by controlling the load on the engine). Regardless of controlling the engine speed to be substantially constant at the rated speed, so-called isochronous control)
It has been disclosed that.

[Problems to be solved by the invention]

However, even if the above-described isochronous control is executed, a trouble that the engine is stopped occurs when the load on the engine becomes excessive.

To avoid this inconvenience, it is necessary to know the load state on the engine. However, as described above, the load on the engine is the sum of the load on the traveling unit and the load on the working unit, and the individual load on both It is necessary to know the state of.

By the way, in order to know the load of the traveling unit and the working unit,
Conventionally, generally, the amount of elastic torsional deformation due to the torque of the transmission shaft is detected, and the conversion is performed by converting the proportional relationship between the amount of deformation and the torque of the transmission shaft. However, in order to know the load accurately by this method, the diameter of the transmission shaft must be reduced so that the transmission shaft is easily torsionally deformed in response to a small change in load. There is a problem in that the conventional method is not practical for adopting the above-mentioned conventional method for a harvester which is liable to be damaged due to breakage and easily overloaded.

In particular, when the trouble of stopping the engine occurs during the mowing and threshing work, a large amount of grain stalks remain clogged in the handling room or the like. Therefore, it is preferable that the load state of the working unit can be easily detected since another problem such as breakage of the work unit occurs.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problem and to easily detect a load on a working unit.

[Means for solving the problem]

For this reason, the present invention transmits the power from the engine mounted on the harvester to the traveling unit via the hydraulic drive unit capable of speed change control, while transmitting the power from the engine to the working unit in parallel with the hydraulic drive unit. Control to operate the adjustment position drive means in the fuel supply device so that the engine speed is substantially constant at the rated speed regardless of the magnitude of the load on the engine. In the harvester, the power detection device of the working unit calculates an engine load from a position detection value of the adjustment position driving unit, and calculates a load of the traveling unit from a hydraulic pressure detection value of a hydraulic sensor for the hydraulic driving unit. The load state of the working unit is detected using a calculated value obtained by subtracting the load of the traveling unit from the engine load.

[Functions and Effects of the Invention]

In this way, control is performed such that the adjustment position drive means in the fuel supply device is operated so that the rotation speed of the engine is substantially constant at the rated rotation speed regardless of the magnitude of the load on the engine (so-called isochronous operation). Control), the engine load and the fuel supply amount are in a proportional relationship such that the fuel supply amount increases as the engine load increases. Therefore, the adjustment position of the adjustment position driving means in the fuel supply amount device is controlled. Is detected, the total load on the engine, that is, the sum of the load on the traveling unit and the load on the working unit can be easily determined.

On the other hand, when power is transmitted to the traveling section by hydraulic drive means (a combination of a hydraulic pump and a hydraulic motor), if the load on the traveling section increases, the hydraulic pressure in the hydraulic drive means must also be increased. There is a proportional relationship. Therefore, the pressure can be easily detected by detecting the pressure of the hydraulic pump having a large load on the traveling unit.

Therefore, an engine load is calculated from a position detection value of the adjustment position drive unit, a load of the traveling unit is calculated from a hydraulic pressure detection value of a hydraulic sensor for the hydraulic drive unit, and a calculation is performed by subtracting the load of the traveling unit from the engine load. With the value, the load state of the working unit is detected.

According to this configuration, without directly detecting the load state of the working unit, the execution can be extremely easily performed by the two types of detection means and the calculation means. Therefore, even if the load state cannot be directly detected in the power transmission system of the working unit, the load can be easily detected.

〔Example〕

Next, a description will be given of an embodiment in which the present invention is applied to a combine serving as a harvester. Reference numeral 1 denotes a traveling body of a general-purpose combine having a traveling section including a pair of left and right traveling crawlers 2a and 2b. Is equipped with a threshing device 3,
The handling drum 4 in the handling room of the threshing device 3 is disposed so that the axis thereof is along the traveling direction of the traveling machine body 1, and below it is a swinging sorting device 5 using a receiving net and a sheave and the wind of Karumi Juan. A wind sorting device is provided, and a paddy tank 6 for storing threshed grains is mounted on the side of the threshing device 3 (on the right side of the traveling machine body 1 in FIG. 1).

The harvesting pretreatment device 7 is opened at the front of the threshing device 3 and has a rectangular cylindrical feeder house 9 (with a chain conveyor 9a inside) that can be moved up and down by a hydraulic cylinder 8; and a front end of the feeder house 9. A horizontally long bucket-shaped platform 10 continuously provided, a horizontally long scraping auger 11 horizontally provided in the platform 10, a reel 13 with a tine bar 12 at a front upper position thereof, and a left and right longitudinally disposed on the lower surface side of the platform 10. And a clipper-shaped cutting blade 14. Code 15,1
Reference numeral 5 denotes a pair of right and left weeds that protrude forward from both left and right front portions of the pre-cutting device 7.

FIG. 3 is a transmission system diagram schematically showing power transmission from the engine 16 to the traveling section and the working section, and reference numeral 17 denotes a traveling clutch device for turning on / off power transmission to the traveling section.
Reference numeral 18 denotes a threshing clutch device for turning on / off the power transmission to the entire working unit such as the threshing unit, and reference numeral 19 denotes a cutting clutch device for turning on / off the power transmission to the pre-cutting processing device 7.

On the downstream side of the drive of the traveling clutch device 17, a hydraulic pump 20 is provided.
And a hydraulic motor 21 comprising a hydraulic motor 21 for driving the drive wheels 25, 25 of the pair of traveling crawlers 2a, 2b.

Reference numeral 23 denotes an electric actuator for increasing or decreasing the output (discharge flow rate, oil pressure) of the hydraulic pump 20, and controls an output signal value (current value) to each actuator 23 by an electric control such as a microcomputer described later. By changing the output signal from the means 24, the swash plate angle in the hydraulic pump 20 is adjusted to increase or decrease the discharge flow rate per unit time,
The rotation number and the rotation direction of the hydraulic motor 21 are configured to be changeable in the forward and reverse directions.

Reference numeral 26 denotes a hydraulic pressure sensor for detecting a hydraulic pressure value in the hydraulic drive means 22 (detection of a hydraulic pressure value from the hydraulic pump 20 to the hydraulic motor 21), such as a Bourdon-type pressure sensor or a bellows-type pressure sensor. Using sensors, etc.
The detected value is extracted as an electric signal.

The power transmission to the cutting pre-processing device 7 is performed by driving the chain conveyor 9a in the feeder house 9 on the downstream side of the driving of the cutting clutch device 19, and using the scraping plate 9b to move the platform.
The harvested culm from 10 is transported to the front of the threshing device 3. On the other hand, power is transmitted to the mowing section speed change mechanism 27 via the chain,
The scraping auger 11, the cutting blade 14, and the reel 13 are each driven at a predetermined speed.

In addition, the power is branched on the drive upstream side of the mowing clutch device 19, and is transmitted to the Karino fan 28, the swing sorting device 5, the grain conveyors 29, 30, 31 and the like.

Reference numeral 24 shown in FIG. 4 denotes control means for adjusting the vehicle speed and turning of the traveling body. The control means 24 includes a central processing unit (CPU) controlled by an electronic control such as a microcomputer, and a central processing unit. Control programs needed to
A read-only memory (ROM) for preliminarily storing an initial value, a calculation map and the like necessary for a conversion calculation described later, and a readable and writable memory (ROM) for temporarily storing various input data used for calculation processing RAM) and an input / output interface, and the following input / output units are connected.

That is, a vehicle speed sensor 32 in the traveling section, a rotation speed sensor 33 such as a pulse encoder provided on an output shaft of the engine 16 or an output shaft of a transmission case or the like for detecting the rotation speed of the engine 16, and a power automatic control described later. Automatic switch 34 to be activated by ON, harvesting pre-processing device 7
ON / OFF switch of the harvesting clutch 35 that is activated by ON, ON / OFF switch of the threshing clutch 36 that activates the threshing clutch device 18 by ON, a hydraulic sensor 26 in the hydraulic drive unit 22, and a fuel in a fuel supply unit 40 described below. The position sensor 38 of the adjustment position driving means 39 for adjusting and controlling the supply amount is connected to the input port, and the electromagnetic actuator 23 and the electromagnetic force of the reaping clutch 19 for changing and adjusting the angle of the swash plate with respect to the hydraulic pump 20 of the traveling crawlers 2a, 2b. The solenoid 41, the ON / OFF switch of the auger clutch 46 of the discharge auger 45 for discharging the grain from the paddy tank 6 to the outside, and the like are connected to the output port.

Further, the output port of the control means 24 is provided with a position driving means 39 for adjusting the amount of fuel supplied to the fuel supply means 40 for adjusting the amount of fuel supplied to the engine 16, and the automatic switch 34 is turned on.
An automatic lamp 42 that lights up at the time of operation to indicate that automatic operation is being performed, and a load state of the work unit described later is displayed by characters such as liquid crystal, and a load display such as overload of the work unit is displayed as a warning display lamp. Are connected to each other.

Note that, for example, another automatic changeover switch means in a working unit of an air conditioner or the like (cooler or the like) in a driver's seat may be connected to the output port of the control means 24.

The fuel supply means 40 is a fuel injection pump installed at a location such as a throttle valve or an air flow meter of a carburetor of an intake system when the engine 16 is a gasoline engine, and directly in a cylinder when the engine 16 is a diesel engine. In the case of the throttle valve, an actuator such as a solenoid for rotating a valve operating shaft for operating the opening / closing degree of the throttle valve is used as a fuel injection pump for injecting the fuel. In the case of a fuel injection pump, it is an actuator such as a step motor which is attached to a rack 43 for adjusting the position of a plunger for adjusting the injection amount and moves the same.

The position sensor 38 may be a potentiometer for detecting the rotation angle of the throttle valve, or a linear differential transformer type displacement sensor that can be attached in parallel with the rack 43 and detect the moving position of the rack.

In the following embodiment, the fuel supply amount adjustment position driving means 39
At the moving position of the rack 43 of the fuel injection pump (hereinafter referred to as rack position (g)). The rack position can be known from the output signal from the position sensor 38 as described above.

The control means 24 stores two engine characteristic modes such as an engine characteristic curve of the engine in advance. Part 1
The two engine characteristic modes are isochronous control modes in which the engine speed is substantially constant at the rated speed regardless of the magnitude of the load on the engine. The engine characteristic mode shown in FIG. The rotation speed (rpm), the vertical axis is the shaft output shaft (PS)], and the vertical axis extending from the point B to the point A at the position of the set rotation speed Nt such as the rated rotation speed is indicated by a line (a) substantially parallel to the vertical axis.

The other engine characteristic mode is a reverse droop control mode in which the engine speed increases in a range smaller than the rated speed when the load on the engine increases, and the engine speed is lower than the rated speed Nt. The position is indicated by a curved line (b) extending from point C to point A.

 The curve (c) is a normal engine characteristic curve.

The storage of the two engine characteristic modes is a map corresponding to the engine characteristic line shown in FIG. 5 (a data number table of a set of the shaft output and the engine speed) or an arithmetic expression that approximates the engine characteristic line. good.

Next, an aspect of the isochronous control and the reverse droop control will be described.

That is, in one embodiment of the isochronous control mode for controlling the engine speed to be constant regardless of the magnitude of the load on the engine in the harvesting operation state by the harvester, the engine speed at no load ( N),
The engine speed is to be maintained at a predetermined set speed regardless of a change in load, based on a relational expression (or map) with the rack position (g).

That is, as shown in FIG. 6, the control means 24 controls the engine speed (N) and the rack position (g) using the load as a parameter, such as at no load, at rated output, and at an arbitrary load during that time. Is stored in advance. As an example, the straight line (d) is when there is no load,
The straight line (e) is at the rated output (Pt), the straight line (f) is at the output (P1), and the straight line (g) is at the output (P2).

Now, assuming that the point D on the straight line (d) at the time of no load is the rack position (go) in the case of the set number of rotations (Nt), the load is (P1) due to the mowing work (the engine at this time). (Corresponding to the shaft output), the intersection E between the line drawn vertically downward from the point D and the straight line (f)
The rotation speed (N1) is reduced to a point. That is, if the rack position is fixed at (go), the fuel supply amount is insufficient and the output of the engine is reduced.

This rotation speed (N1) can be detected by the rotation speed sensor 33.

Therefore, in order to increase the output of the engine to the point G at the set rotation speed (Nt) on the straight line (f), it is necessary to move the rack position to (g1).

Therefore, a correction calculation formula (map) based on the difference between the gradient of the straight line (d) at the time of no load and the gradient of the straight line (f) at the time of load (P1) is stored, and the difference between the reduced rotational speeds is stored. The increment (Δg1) of the rack position corresponding to (Nt−N1) is calculated from the correction formula, the target rack position (g1) is obtained, and the output signal is sent to the adjustment position driving means 39, and the fuel supply amount is calculated accordingly. By increasing accordingly,
The engine speed can be maintained at the set speed (Nt) despite the increased load.

Similarly, for example, if the load fluctuates (increases) while the mowing work is being performed with the load (P1) and the load (P2) is reached, the rated speed (Nt) on the straight line (f) , The rotation speed (N2) drops from the point G to the point F vertically below.

In order to restore the rack position (g1) to the rack position (g2) in order to recover to the point H corresponding to the set rotation speed (Nt) under the state of the load (P2), a target is calculated by a correction arithmetic expression presupposed in advance. An output signal is issued so as to drive the adjustment position drive means 39 in order to obtain the rack position.

As can be understood from FIG. 6, J corresponding to the maximum rack position (gm) in the rated output state indicated by a straight line (e).
A section from a point (assuming the engine speed (Nm)) to a rack position (I) on a straight line (d) with no load to obtain the same engine speed is point (I) is the engine speed ( Nm)
, The rack position can be changed. Similarly, the rack changeable section from the no-load rack position to the rated output rack position at an arbitrary predetermined rotation speed (N) lower than this rotation speed is: It can be seen that it decreases as the engine speed decreases. Therefore, it can be understood that the above-mentioned correction operation expression is also a function of the engine speed.

Next, the engine speed (Ne) set at the time of switching to the reverse droop control (this is lower than the rated speed)
When the rack position corresponding to is detected, the load is increased based on this position, and if the load is increased, the control is performed so that the rack position is quadratically displaced in the direction in which the rack position is increased. Since the increased load and the output of the engine become equilibrium at the position where the rotation speed of the engine slightly increases, even if the load increases, the inconvenience of losing the increased load and stopping the engine is eliminated. .

Further, by setting the rotation speed of the engine during the reverse droop control to be lower than the rated rotation speed, the amount of fuel supplied to the engine can be kept low, and power loss can be prevented.

FIG. 7 shows a position sensor 38 for detecting the position of the rack 43.
FIG. 8 is a diagram showing a proportional relationship between a detected value (unit: voltage) and a fuel supply amount to the engine 16, and FIG. 8 is a diagram showing a proportional relationship between a fuel injection amount and an engine load. The ratio is experimentally obtained as a parameter, and this proportional relationship is stored in advance in a ROM as a data map. From the relationship with FIGS. 5 and 6, the position detection value (position The engine load Le (unit: horsepower, etc.) is calculated from the detected value of the sensor 38)
Calculated by the calculation unit in 24.

On the other hand, the detection value of the pressure sensor 26 shown in FIG.
Voltage) and the hydraulic pressure value of the hydraulic drive means 22 (unit: gauge pressure)
And the proportional relationship between the hydraulic pressure value P (unit: gauge pressure) of the hydraulic drive means 22 and the load Lc (unit: horsepower, etc.) of the traveling unit in FIG. Each is stored in the ROM, and if the detected value P of the oil pressure is known from the relationship with FIGS.
The calculation unit of the control means 24 calculates the magnitude of Lc so that the magnitude can be determined.

Then, according to the flowchart of FIG. 11 (only the subroutine for detecting the load of the working unit is shown), the load Ls
(Unit: horsepower or the like) is calculated and detected by the control means 24.

That is, following the start of the flowchart of FIG. 11, in step S1, the load Lc of the traveling unit is read, and
In step S2, the engine load Le is read, and in step S3, Le−Lc
= Ls is calculated.

With this configuration, the load state of the working unit can be extremely easily detected without providing the detecting unit in the working unit itself.

Next, in step S4, the load Ls of the working unit is compared in magnitude with a preset overload Lm (for example, an experience value obtained when the threshing apparatus is overloaded), and the load of the working unit is determined in step S4. When it is determined that Ls is smaller than the overload Lm (no), it is sufficient to run at that speed and execute the work under that load condition. In that case, in step S5, the fact is displayed on the display device 44 in step S5. Turn off the overload warning lamp.

Conversely, in step S4, the load Ls of the working unit is
If it is determined to be larger (yes), step S6
It is determined whether the cutting clutch 35 and the threshing clutch 36 are on or off, and these clutches 35 and 36 are on (yes).
Is determined, an overload warning lamp is lit in step S7 to display an overload state. Then, at this time, in step S8, the traveling speed of the traveling unit is shifted to the deceleration side by automatic control or manually, and the vehicle is immediately returned to the appropriate load state.

FIG. 12 shows another embodiment of the control flow after step S4 in the flowchart of FIG.
In step S10 of the drawing, the load Ls of the working unit obtained by the calculation in the above-described embodiment is compared with a preset idling load La.
Is performed, and in step S10, the load Ls
Is greater than the idling load La (yes), it is determined in step S11 whether the threshing clutch 35 is ON. If the clutch is ON (yes), the discharge auger clutch 46 is ON in step S12. If it is determined in this step S12 that the discharge auger clutch 46 is off (no), an indication that threshing is in progress is displayed on the display device in step S13. In such a situation,
Since the load at the threshing unit is large, the worker is warned not to apply a larger load. For example,
The worker is warned not to carry out the work of carrying out the grain from the paddy tank 6 by turning on the discharge auger clutch 46.

In step S10, when the load Ls of the working unit is smaller than the idling load La (no), or in step S11,
In the determination of, when the determination of yes is made in step S12, a display indicating that there is no threshing work is performed (step S14), and when this display is displayed, work other than the threshing work may be performed.

[Brief description of the drawings]

Drawings show an embodiment of the present invention, FIG. 1 is a plan view of a combine, FIG. 2 is a side view, FIG. 3 is a view showing a power transmission system,
FIG. 4 is a control block diagram, FIG. 5 is an engine characteristic diagram showing an isochronous control mode and a reverse droop control mode, FIG. 6 is an explanatory diagram showing a relationship between an engine speed and a rack position, and FIG. 8 is a diagram showing the relationship between the position and the fuel injection amount, and FIG.
FIG. 9 is a diagram showing the relationship between the fuel injection amount and the engine load, FIG. 9 is a diagram showing the relationship between the detected value of the pressure sensor and the oil pressure, FIG. 10 is a diagram showing the relationship between the oil pressure and the load of the traveling unit, FIG. The figure is a flowchart of another embodiment. DESCRIPTION OF SYMBOLS 1 ... Traveling body, 2a, 2b ... Traveling device, 3 ... Threshing device, 7 ... Harvesting pre-processing device, 16 ... Engine, 20 ... Hydraulic pump, 21 ... Hydraulic motor, 22 ... Hydraulic drive Means, 23
…… Actuator, 24… Control means, 26 …… Hydraulic sensor, 33 …… Rotation speed sensor, 35 …… Mowing switch, 36
... Threshing sensor, 38 ... Position sensor, 39 ... Adjustment position drive means, 40 ... Fuel supply means, 43 ... Rack, 44 ...
... display device.

Claims (1)

(57) [Claims] 1. The power from an engine mounted on a harvester is transmitted to a traveling unit via a hydraulic drive unit capable of shifting control, and the power from an engine is transmitted to a work unit in parallel with the hydraulic drive unit. The control is performed so that the adjustment position driving means in the fuel supply amount device is operated so that the rotation speed of the engine is substantially constant at the rated rotation speed regardless of the magnitude of the load on the engine. In the harvester, an engine load is calculated from a position detection value of the adjustment position driving unit, a load of a traveling unit is calculated from a hydraulic pressure detection value of a hydraulic sensor for the hydraulic driving unit, and a load of the traveling unit is subtracted from the engine load. A power detection device for a working unit in a harvester, wherein a load state of the working unit is detected using the calculated value.