JP3798896B2 - Overload prevention device for combine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an overload prevention device for a combine. More particularly, the present invention relates to an overload prevention device for a combine that automatically cuts and thresh grains and stores the grains.
[0002]
[Prior art]
The combine is configured so that the harvesting unit cuts cereals one after another while being advanced by the traveling device, the cereals are sent to the threshing unit by the transport device, and the threshing unit threshes.
Therefore, when the forward speed of the combine is high, the amount of harvested cereals increases, so the load amount at the threshing portion increases.
[0003]
On the other hand, in order for the combine to work efficiently, conventionally, automatic control has been performed in which the engine is operated near the maximum output to advance the combine and drive the threshing unit. In this case, the engine is automatically controlled to maintain the rated speed.
[0004]
Looking more specifically at the above control details, the engine speed (horsepower or torque) is set slightly higher than the maximum output value of the engine output (horsepower or torque) as the rated speed, and at this rated output ( output at the rated speed) During the work, the fuel injection amount is controlled so as to maintain the engine at the rated speed even if the load increases or decreases somewhat. And if it is a little, load will increase (namely, the amount of cereal will increase), and even if an engine speed falls, it will be able to continue work with maximum horsepower (or maximum torque). That is, it is rated automatic operation.
Of course, if the amount of cereals is excessively large than usual, the engine will stop, so in this case, the combine driver usually reduces the vehicle speed manually to reduce the load (the amount of cereals) Try to eliminate overload. In this way, it is only necessary to eliminate the overload manually, but if the manual operation is not in time or there is too much harvested culm, the engine will stop.
[0005]
[Problems to be solved by the invention]
If the engine stops due to overload as described above, excessive force is applied to each part of the combine, causing damage. Moreover, it is troublesome to eliminate the overload manually, and it cannot be completely eliminated.
[0006]
SUMMARY OF THE INVENTION In view of such circumstances, the present invention provides an overload prevention device for a combine that automatically resolves an overload on an engine when an excessive load is applied during rated automatic operation and allows a smooth threshing operation to be continued. For the purpose.
[0007]
[Means for Solving the Problems]
According to another aspect of the present invention, there is provided an overload prevention device for a combine that uses a common engine to transmit the engine output to the vehicle body via one output shaft of a hydrostatic transmission so that the combine travels and the mowing unit and the transport unit operate. An overload prevention device for a combine that transmits to a traveling device and transmits the other output shaft to a mowing unit and a conveying unit , and includes a controller and an operation device for the hydrostatic transmission. The controller sets the rated speed of the engine to a speed slightly exceeding the speed at the maximum output, and maintains the rated speed even if the load increases to some extent during work at this rated speed. And controlling the hydrostatic transmission at a constant speed in an overload state where the engine speed is less than a reference value below the rated speed and the engine load is greater than the reference value. And a control signal generating means for operating the decelerating position to return to the original constant speed position when the overload condition is resolved, and the operating device is a mechanical mechanism for operating the internal transmission mechanism of the hydrostatic transmission. An output means; a manual transmission lever that is a manual input means and provided in a combine driver's seat; an automatic transmission means that is an automatic input means and driven by a control signal from the controller; and a movement of the manual transmission lever. A one-way transmission mechanism is provided which transmits the movement of the automatic transmission unit to the mechanical output unit and the manual transmission lever without transmitting to the automatic transmission unit but transmitting it to the mechanical transmission unit.
The overload prevention device for a combine according to claim 2, wherein the one-way transmission mechanism includes a gear train that transmits the output of the motor, a main shaft that is rotated by the gear train and has an output side link directly connected thereto, and the shift lever. And a spring-biased friction plate connected to the main shaft .
[ 0008]
According to invention of Claim 1, there exists the following effect.
1) When the engine speed falls below the reference value and the engine load exceeds the reference value, the overload control device is automatically determined as overload, and the automatic transmission unit is driven by the control signal from the controller, Since the mechanical output means of the operating device operates the internal transmission mechanism of the hydrostatic transmission to the deceleration position, the forward speed of the combine is reduced. For this reason, since the amount of cutting and transporting cereals is reduced, the load is reduced and the overload is eliminated. When the overload is eliminated, the load is automatically determined to be appropriate, and the automatic transmission unit is driven by the control signal from the controller, and the mechanical output means of the operating device returns to the original transmission mechanism of the hydrostatic transmission. Since it returns to the position, the forward speed of the combine increases. Thereby, the rated automatic operation is resumed. In this way, the overload is automatically eliminated.
2) The movement of the automatic transmission when an overload occurs and the vehicle automatically decelerates or returns to the rated automatic operation after the overload is resolved is transmitted to the manual transmission lever, and the manual transmission lever moves. There is an advantage that it is possible to know sensuously whether the operation has become a decelerating operation or a constant speed operation. In addition, since the movement of the manual shift lever is not transmitted to the automatic transmission unit by sliding the friction plate, the driver can decelerate / return at his / her own discretion. Will not be damaged.
3) Since the controller operates to maintain the rated speed of the engine even if the load increases to some extent in a state where there is no overload, the work efficiency does not fluctuate frequently during work, and work that is strong even in a state close to overload Can continue.
According to the invention of claim 2, since the one-way transmission mechanism uses a spring-biased friction plate, the frictional force can be accurately set and adjusted, and the force transmission blocking action is reliable .
[ 0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings.
FIG. 5 is a schematic side view of a combine to which the present invention is applied, FIG. 6 is a schematic plan view of the combine, and FIG. 7 is a block diagram of a drive system of the combine.
[0010]
First, a basic configuration of a combine to which the present invention is applied will be described with reference to FIGS.
5 to 6, reference numeral 1 denotes a traveling device such as a crawler, and a machine base 2 is attached to the upper surface of the traveling device 1. A mowing unit 3 and a conveying unit 4 are attached in front of the machine base 2, and a threshing unit including a feed chain 5, a handling cylinder 6, and a processing cylinder 7 is provided on the upper surface of the machine base 2, and a shell grain for storing the threshed shell grains A tank 8, a discharge auger 9 for unloading the shell grains in the shell grain tank 8, a driving cabin 12 including a driving operation unit 10 and a driver's seat 11, an engine 13 as a power source for the combine are mounted. Although not shown, it also has a sorting unit and a straw processing unit.
The harvesting unit 3 includes a pulling device 3a, a harvesting device 3b, and a scraping device 3c. The transport unit 4 includes a lower transport unit 4a, a vertical transport unit 4b, and a transport tine 4c.
[0011]
FIG. 7 is a block diagram of the combine drive system. The output of the engine 13 is transmitted to the hydrostatic transmission 14 via the travel clutch CL1, and one of the two main shafts of the hydrostatic transmission 14 is Power is transmitted to the cutting unit 3 (the pulling device 3a, the cutting device 3b, the scraping device 3c) and the conveying unit 4 via the cutting clutch CL2, and another output shaft of the hydrostatic transmission 14 is the traveling device 1. Power is being transmitted to The output of the engine 13 is transmitted to the handling cylinder 6 and the processing cylinder 7 via the threshing clutch CL3, and further to the feed chain 5 via the clutch CL4 and to the discharge auger 9 via the clutch CL5. ing.
[0012]
As described above, the engine 13 is used for both driving and driving of each part of the threshing. And if the forward speed of the combine is fast, a large amount of cereal is harvested, conveyed and threshed, so that the threshing load increases. In addition, when the forward speed of the combine is slow, the amount of cereals decreases, so the threshing load decreases.
[0013]
Next, details of the overload control device will be described with reference to FIGS.
As shown in FIG. 1, the engine 13 is controlled by a dedicated engine controller 21 for rated operation so as to rotate at a rated rotational speed (for example, 2800 rpm) slightly exceeding the maximum output rotational speed. It has become. That is, by changing the position of the rack 23 of the fuel injection device 22 according to the control signal of the controller 21, even if the fuel injection amount is changed and the load is slightly increased or decreased, the injected fuel is increased or decreased to bring the engine speed close to the rated value. I try to keep it. If the load, that is, the amount of cereal, increases slightly, the engine speed will decrease slightly, but the engine speed will be the maximum output range of the engine. It can be used to thresh somewhat larger grains.
A load sensor 24 detects the current load factor of the engine by detecting the position of the rack 23. Reference numeral 25 denotes a rotation speed sensor that detects the rotation speed of the engine 13.
[0014]
The output of the engine 13 is transmitted to the traveling device 1 via the hydrostatic transmission 14 as described above, and the hydrostatic transmission 14 can change the output rotation speed by the operating device 30. It has become. The hydrostatic transmission 14 is a known continuously variable transmission comprising an axial plunger pump driven by the engine 13 and a motor connected to the pump by a hydraulic circuit, and the angle of the swash plate 14c of the pump is changed. The discharge amount of the pump changes, and the output rotation speed of the motor changes.
[0015]
The operating device 30 includes a manual shift lever 15 that is a manual input unit and a motor 43 that is an automatic transmission unit, and the output side link 36 that is a mechanical output unit is swung by an input from either of them. It has become. The output side link 36 changes the angle of a swash plate 14c, which is an internal transmission mechanism of the hydrostatic transmission 14, via an arbitrary connecting member such as a connecting link on the way or a push / pull control cable. Details of the operating device 30 will be described later.
[0016]
The manual transmission lever 15 is installed beside the driver's seat 11 as shown in FIG. 6, and is operated by the driver with the left hand.
[0017]
In FIG. 1, reference numeral 20 denotes a controller using a microcomputer or the like, which is a function realization means for executing first and second overload determination means and control signal output means of the overload control device. The ROM of the controller 20 stores an overload control program, and the RAM temporarily stores input information from each sensor. Based on the ROM program, the CPU calculates using the information stored in the RAM and outputs each control signal.
[0018]
In addition, detection signals from the load sensor 24, the rotational speed sensor 25, the vehicle speed sensor 26 attached to the traveling device 1, and the rotational position sensor 53 of the operating device 30 are input to the input port of the controller 20, Control signals are output from the output port to the drive circuit 28 for the monitor lamp 27 and the buzzer 27d, and to the drive circuit 29 for the motor 43 which is an automatic transmission unit of the operating device 30.
[0019]
The monitor lamp 27 may be a single lamp, but it is preferable to use, for example, three colored lamps, that is, green 27a, yellow 27b, and red 27c. If the green 27a is lit during normal operation, the yellow 27b is lit during rated automatic operation, and the red 27c is lit during overload, there is an advantage that each state of the combine can be distinguished well.
[0020]
Next, details of the operating device 30 will be described.
FIG. 2 is a front view of the main part of the operating device 30, and FIG. 3 is a sectional view of the operating device 30.
2 and 3, reference numeral 31 denotes an operation plate, which is rotatably attached around a main shaft 32. The main shaft 32 is supported by a casing 34 via a bearing 33. The base of the manual transmission lever 15 is fixed to the end of the operation plate 31 above the main shaft 32. Further, the output side link 36 is connected to an end portion of the operation plate 31 below the main shaft 32 through a pin 35. A large gear 37 is fixed to one end of the main shaft 32 inside the casing 34. On the other hand, a small gear 38 and a wheel 39 are coaxially connected to another support shaft 41, the small gear 38 meshes with the large gear 37, and the wheel 39 meshes with the worm 42. This worm 42 is driven by a motor 43. Therefore, when the motor 43 rotates, the rotational drive force is transmitted to the worm 42 → the wheel 39 → the small gear 38 → the large gear 37, and the main shaft 32 rotates.
[0021]
Friction plates 44 are interposed one by one around the main shaft 32 in contact with the back and front of the operation plate 31, and are sandwiched between a fixed plate 45 fixed to the main shaft 32 and a pressing plate 46. Yes. A disc spring 47 is disposed behind the pressing plate 46, the disc spring 47 is pressed by a pressing plate 48, and the tightening amount of the disc spring 47 can be variably adjusted by a nut 49. 32a is a male screw formed at the tip of the main shaft 32.
[0022]
The frictional force between the friction plate 44 and the operation plate 31 rotates the operation plate 31 when the main shaft 32 rotates. However, when the operation plate 31 is rotated, an excessive force is not applied to the main shaft 32. is there.
[0023]
Therefore, the operating device 30 operates as follows.
When the main shaft 32 is rotated by the motor 43, the operation plate 31 swings through the frictional force of the friction plate 44. As a result, the output side link 36 moves to change the angle of the swash plate 14c of the hydrostatic transmission 14 shown in FIG. At this time, since the manual transmission lever 15 swings together with the operation plate 31, the driver knows that the operation of the manual transmission lever 15 is decelerated with the naked eye or with the sense of the left hand while in the cab. Can do. This is the same for the deceleration operation and the return operation.
[0024]
On the other hand, when the manual transmission lever 15 is manually operated, the operation plate 31 is directly moved, and the output side link 36 swings. The movement of the operation plate 31 is not forcibly transmitted to the main shaft 32 by the sliding of the friction plate 44. Therefore, the gear train and the motor 43 whose rotation from the gear side is locked by the worm 42 and the wheel 39 are not damaged.
[0025]
2 and 3, reference numeral 51 denotes a coupling plate connected to the lower end of the operation plate 31, and a pin 52 is implanted therein. On the other hand, 53 is a rotational position sensor such as a potentiometer, and its actuator 54 is in contact with the pin 52.
Therefore, when the operation plate 31 swings, the position is detected by the rotational position sensor 53, and the current shift position can be grasped.
[0026]
Next, the overload control method of the present invention will be described with reference to FIG.
In the present embodiment, the engine speed of the rated speed, that is, the rotational speed of the rated during operation, for example, a 2800 rpm, the reference value 2700 rpm, the engine load ratio is a reference value of 95%. Whether or not the traveling device 1 is traveling at a constant speed is determined based on a detection signal of the vehicle speed sensor 26.
When the engine speed falls below 2700 rpm (step 101) and the engine load factor exceeds 95% (step 102), the first determination means determines that the engine is overloaded. This determination is made based on the load sensor 24 and the rotation speed sensor 25 of the engine 13.
[0027]
If it is determined that the vehicle is overloaded, a control signal is output (step 103), the motor 43 of the operating device 30 is driven, the hydrostatic transmission 14 is decelerated, and, for example, the vehicle speed is reduced by 15%.
Further, during this deceleration operation, the red third lamp 27c blinks in response to a control signal so as to attract more attention of the operator. Therefore, the operator can also perform an operation to reduce the vehicle speed manually. As a result, the combine is decelerated (step 104).
[0028]
In this manner, when the vehicle speed is reduced and the load is reduced and the overload state is resolved (step 105), the motor 43 of the operating device 30 is reversed by the control signal from the controller 20, and the hydrostatic transmission 14 Return to the original constant speed position. Then, the combine returns to the rated automatic operation (step 107), and the monitor lamp 27 turns on the yellow second lamp 27b.
[0029]
In step 105, if the second determination means determines that the load is still excessive, the buzzer 27d sounds and warns (step 108). At this time, the driver presses the manual operation lever 15. It is only necessary to operate in the deceleration direction, so that overload that could not be resolved even with 15% deceleration can be eliminated.
[0030]
While the automatic overload control is performed as described above, the manual transmission lever 15 moves and it is easy to notify the operator of the overload state. In addition to the automatic control system, it is of course possible to manually operate the manual shift lever 15 to eliminate the load.
[0031]
【The invention's effect】
According to invention of Claim 1, there exists the following effect.
1) In an overload condition, the forward speed of the combine is automatically reduced to eliminate the overload, and when the overload is removed, the forward speed of the combine is automatically returned to constant speed, so the overload is automatically Is eliminated and damage to the combine is prevented.
2) When the vehicle is overloaded and automatically decelerates, the manual shift lever moves in the same manner as when the operator intentionally sets the decelerating position, so that the operator can know sensuously that the operator has decelerated.
3) Since the controller operates to maintain the rated speed of the engine even if the load increases to some extent in a state where there is no overload, the work efficiency does not fluctuate frequently during work, and work that is strong even in a state close to overload Can continue.
According to the invention of claim 2, since the one-way transmission mechanism uses a spring-biased friction plate, the frictional force can be accurately set and adjusted, and the force transmission blocking action is reliable .
[ Brief description of the drawings]
FIG. 1 is a block diagram of an overload prevention apparatus according to an embodiment of the present invention.
FIG. 2 is a front view of a main part of the operating device 30. FIG.
3 is a cross-sectional view of the operating device 30. FIG.
FIG. 4 is a flowchart of overload control in the present invention.
FIG. 5 is a schematic side view of a combine to which the present invention is applied.
FIG. 6 is a schematic plan view of the combine.
FIG. 7 is a block diagram of a drive system of the combine.
[Explanation of symbols]
13 Engine 14 Hydrostatic transmission 15 Manual shift lever 20 Controller 27 Monitor lamp 30 Operating device 43 Motor

Claims (2)

The engine output is transmitted to the vehicle body travel device via one output shaft of the hydrostatic transmission, and the other output shaft is used to drive the combine and operate the harvesting unit and the transport unit with a common engine. Is an overload prevention device in a combine that is adapted to transmit to a cutting part and a conveying part ,
A controller and an operation device for the hydrostatic transmission,
The controller sets the rated speed of the engine to a speed slightly exceeding the speed at the maximum output, and maintains the rated speed even if the load increases to some extent during work at this rated speed. And operating the hydrostatic transmission from a constant speed position to a deceleration position in an overload state where the engine speed is below a reference value below the rated speed and the engine load is above the reference value, It is equipped with control signal generation means that returns to the original constant speed position when the overload condition is resolved.
The operating device includes a mechanical output means for operating an internal speed change mechanism of the hydrostatic transmission, a manual shift lever provided at a combine driver's seat as a manual input means, and an automatic input means from the controller. An automatic transmission unit driven by a control signal and the movement of the manual transmission lever are transmitted to the mechanical output means but not transmitted to the automatic transmission unit, and the movement of the automatic transmission unit is transmitted to the mechanical output unit and the manual transmission unit. An overload prevention device for a combine, comprising a one-way transmission mechanism for transmitting to a lever. The one-way transmission mechanism includes a gear train that transmits the output of the motor, a main shaft that is rotated by the gear train and has an output-side link directly connected thereto, and a spring-biased friction plate that connects the shift lever to the main shaft. It is made of the overload prevention device in combine of claim 1, wherein.

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