JPH11123017A - Overload-preventing device of combine harvester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the overload-preventing device of a combine harvester, enabling the automatic elimination of the load on an engine and the continuation of a smooth threshing operation. SOLUTION: This overload-preventing device in a combine harvester in which the travel of the combine harvester and the operation of a threshing section are executed with a common engine 13 and in which the output of the engine is transmitted to a travel device 1 through a hydrostatic transmission 14 judges whether the rotation number of the engine is smaller that a rated standard value and whether the load of the engine is larger than a standard value, operates the hydrostatic transmission 14 at a speed-reducing position in the overloaded state, and returns the hydrostatic transmission to the original constant rate, when the overload state is eliminated. The movement of the automatic operation is transmitted to a manual gear lever 15 to allow the movement of the manual gear lever 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an overload prevention device for a combine. More specifically, the present invention relates to an overload prevention device in a combine that automatically cuts a culm, threshes, and stores grain.

[0002]

2. Description of the Related Art A combine is configured so that a cutting unit successively cuts a grain stalk while being advanced by a traveling device, sends a grain stalk to a threshing unit by a transport device, and threshes by a threshing unit. Therefore, if the forward speed of the combine is high, the cutting amount of the grain culm increases, and the load on the threshing unit increases.

On the other hand, in order to operate the combine efficiently, automatic control for operating the engine near the maximum output to advance the combine and drive the threshing unit has been conventionally performed. In this case, the engine is automatically controlled to maintain the rated speed.

[0004] Looking more specifically at the above control contents,
The engine speed (horsepower or torque) slightly exceeds the maximum output value as the rated speed, and the engine is maintained at the rated speed even if the load slightly increases or decreases while working at this rated output. Thus, the fuel injection amount is controlled. Then, if the load increases (that is, the amount of cereal stalk increases), and the engine speed drops, the work can be continued at the maximum horsepower (or maximum torque).
That is, rated automatic operation. Of course, if the amount of cereal stalk becomes excessively large than usual, the engine will stop, so in this case, the combine driver usually lowers the vehicle speed manually and reduces the load (the amount of cereal stalk), Try to eliminate overload. As described above, it is sufficient that the overload can be manually eliminated. However, if the manual operation cannot be performed in time, or if the amount of the harvested cereal stem is too large, the engine still stops.

[0005]

When the engine is stopped due to overload as described above, excessive force is applied to each part of the combine, which causes damage. Also, it is troublesome to eliminate the overload manually, and it cannot be completely eliminated.

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention provides an overload prevention device for a combine which automatically cancels an overload on an engine when an excessive load is applied during rated automatic operation, thereby enabling a smooth threshing operation to be continued. The purpose is to provide.

[0007]

According to a first aspect of the present invention, there is provided an overload preventive device for a combine, in which a common engine is used to drive a combine and run a threshing unit, and the rated output of the engine is reduced to the maximum output speed. Set the rotation speed to slightly exceed
A combine that controls the engine to maintain its rated speed even if the load increases or decreases to some extent during the operation at this rated speed, and transmits this engine output to the vehicle body traveling device via a hydrostatic transmission. A determination means for determining whether or not the engine speed is equal to or less than a reference value lower than the rated speed and the engine load is equal to or greater than the reference value; and To a deceleration position, a controller having control signal generating means for operating to return to the original rated position when the overload state is resolved, a mechanical output means for operating the internal transmission mechanism of the hydrostatic transmission, A manual transmission lever provided as a manual input means and provided in a driver's seat of the combine, an automatic transmission unit which is an automatic input means driven by a control signal from the controller, and an operation of the manual transmission lever To the mechanical output unit, but not to the automatic transmission unit, but an operating device having a one-way transmission mechanism for transmitting the movement of the automatic transmission unit to the mechanical output unit and the manual transmission lever. It is characterized by.
The overload prevention device for a combine according to claim 2, wherein the one-way transmission mechanism transmits a gear train transmitting an output of a motor;
It comprises a main shaft rotated by the gear train and directly connected to an output side link, and a spring-biased friction plate connecting the transmission lever to the main shaft. The overload prevention device in the combine according to claim 3, wherein the overload control device turns on a monitor lamp while the hydrostatic transmission is operating to a deceleration position and while returning to a rated position. It is characterized by the following. An overload prevention device for a combine according to a fourth aspect of the present invention includes a second determination unit that determines whether the combine is in an overload state when the combine enters a deceleration operation state by a deceleration operation. A buzzer sounds while the load is determined.

According to the first aspect of the invention, when the engine speed falls below the reference value and the engine load exceeds the reference value, the overload control device is automatically determined to be overload, and the control from the controller is performed. The automatic transmission is driven by the signal, and the mechanical output means of the operating device operates the internal transmission mechanism of the hydraulic control to the deceleration position, so that the forward speed of the combine decreases. For this reason, since the amount of harvested and transported grain is reduced, the load is reduced, and overload is eliminated. When the overload is resolved, the load is automatically determined to be appropriate, and the automatic transmission is driven by the control signal from the controller, and the mechanical output means of the operating device uses the internal transmission mechanism of the hydrostatic transmission as the original. Return to the rated position increases the forward speed of the combine. Thereby, the rated automatic operation is restarted. In this way, the overload is automatically eliminated. Then, the automatic transmission decelerates due to the overload condition, and the movement of the automatic transmission when the overload is resolved and the operation returns to the rated operation is transmitted to the manual transmission lever, and the manual transmission lever moves, so the operator decelerates. There is an advantage that it can be intuitively sensed whether the vehicle has been driven or has been driven at a constant speed. Furthermore, since the movement of the manual transmission lever is not transmitted to the automatic transmission unit due to the sliding of the friction plate, the driver can perform the deceleration / return operation at his / her own discretion. It does not cause damage. According to the second aspect of the present invention, since the one-way transmission mechanism uses the spring-biased friction plate,
The setting and adjustment of the frictional force can be accurately performed, and the effect of blocking the transmission of the force is ensured. According to the third aspect of the present invention, it is possible to easily know that the vehicle is decelerating due to an overload state and that the vehicle has returned to the rated operation by turning on the monitor lamp. According to the fourth aspect of the present invention, the buzzer sounds when the overload is not resolved even after the automatic deceleration operation for eliminating the overload is performed. Can be reliably eliminated.

[0009]

Next, embodiments of the present invention will be described with reference to the drawings. 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.

First, the basic structure of a combine to which the present invention is applied will be described with reference to FIGS. 5 and 6, reference numeral 1 denotes a traveling device such as a crawler, and a machine base 2 is mounted on an upper surface of the traveling device 1. A cutting section 3 and a transport section 4 are mounted in front of the machine base 2, and a threshing section including a feed chain 5, a handling cylinder 6, and a processing cylinder 7 is provided on an upper surface of the machine base 2.
A shell-grain tank 8 for storing threshed shell-grain, a discharge auger 9 for carrying out the shell-grain in the shell-grain tank 8, an operation cabin 12 having an operation unit 10 and a driver's seat 11, an engine 13 which is a power source of a combine, and the like. It is equipped with. Although not shown, a sorting unit and a straw processing unit are also provided. The reaping unit 3 includes a raising device 3a, a reaping device 3b, and a scraping device 3c, and the transport unit 4 includes a lower transport unit 4a and a vertical transport unit 4b.
And a transfer tine 4c.

FIG. 7 is a block diagram of the drive system of the combine. The output of the engine 13 is transmitted to the hydrostatic transmission 14 via the traveling clutch CL1.
One of the main shafts is a reaping unit 3 (raising device 3a, reaping device 3b, and raking device 3c) via a reaping clutch CL2.
Power is transmitted to the transport device 4, and another output shaft of the hydrostatic transmission 14 transmits power to the traveling device 1.
The output of the engine 13 is transmitted to the handling cylinder 6 and the processing cylinder 7 via a threshing clutch CL3.
The power is transmitted to the feed chain 5 via the clutch 4 and to the discharge auger 9 via the clutch CL5.

As described above, the engine 13 is used both for traveling and for driving each unit of threshing. And if the forward speed of the combine is high, a large number of grain rods are cut, conveyed, and threshing, so that the threshing load increases. In addition, when the forward speed of the combine is low, the amount of cereal rods is reduced, so that the threshing load is reduced.

Next, details of the overload control device will be described with reference to FIGS.
It will be described based on. As shown in FIG.
Reference numeral 3 denotes a dedicated engine controller 21 for rated operation, which is controlled so as to rotate at a rated speed (for example, 2800 rpm) slightly exceeding the maximum output speed. 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, the amount of injected fuel is increased or decreased even if the fuel injection amount is changed and the load is slightly increased or decreased. I try to keep it. In addition, when the load, that is, the amount of the grain rod is slightly increased, the engine speed slightly decreases, but since that speed is the maximum output range of the engine,
The engine doesn't stop easily, it can stick out and thresh a bit more grain. Reference numeral 24 denotes a load sensor that detects the current load ratio of the engine by detecting the position of the rack 23. 25 is engine 1
3 is a rotation speed sensor for detecting the rotation speed.

The output of the engine 13 is transmitted to the traveling device 1 through the hydrostatic transmission 14 as described above. The output speed of the hydrostatic transmission 14 is controlled by the operating device 30. The gear can be changed. The hydrostatic transmission 14 is a known continuously variable transmission including an axial plunger type pump driven by the engine 13 and a motor connected to the pump by a hydraulic circuit.
When the angle of 14c is changed, the discharge rate of the pump changes and the output speed of the motor changes.

The operating device 30 includes a manual shift lever 15 as a manual input unit and a motor 43 as an automatic shift unit.
The output side link 36, which is a mechanical output means, is swung by an input from any of them. 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 or a push-pull control cable. Details of the operation device 30 will be described later.

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 his left hand.

In FIG. 1, reference numeral 20 denotes a controller using a microcomputer or the like, which is a function realizing means for executing first and second overload determining means and control signal output means of the overload control device. ROM of this controller 20
Stores an overload control program.
M temporarily stores input information and the like from each sensor. C
The PU performs a calculation based on the program stored in the ROM using the information stored in the RAM, and outputs each control signal.

Further, detection signals of the load sensor 24, the rotation speed sensor 25, the vehicle speed sensor 26 attached to the traveling device 1, and the position sensor 33 of the operation device 30 are input to input ports of the controller 20. From the output port, a drive circuit 28 for a monitor lamp 27 and a buzzer 27d and a motor
The control signal is output to the third drive circuit 29.

The monitor lamp 27 may be a single lamp, for example, three types of colored lamps, ie,
It is preferable to use green 27a, yellow 27b, and red 27c. Green 27a lights up during normal operation and turns yellow.
When 27b is lit during rated automatic operation and red 27c is lit during overload, there is the advantage that each state of the combine can be distinguished well.

Next, the operation device 30 will be described in detail.
FIG. 2 is a front view of a main part of the operation device 30, and FIG.
FIG. In FIGS. 2 and 3, an operation plate 31 is rotatably mounted around a main shaft 32. The casing 3 is attached to the main shaft 32 via a bearing 33.
4 supported. The root of the manual transmission lever 15 is fixed to an end of the operation plate 31 above the main shaft 32. In addition, at the end of the operation plate 31 below the main shaft 32,
The output side link 36 is connected via 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, small gear 3
The wheel 8 and the 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. The worm 42 is driven by a motor 43. Therefore, when the motor 43 rotates, the worm 42 → the wheel 39 → the small gear 38
→ The rotation driving force is transmitted to the large gear 37, and the main shaft 32 swings.

The spindle 32 is in contact with the front and back of the operation plate 31.
Around each of the friction plates 44, a fixed plate 45 fixed to the main shaft 31 and a pressing plate 4 are provided.
6 between. A disc spring 47 is arranged behind the pressing plate 46, and the disc spring 47 is pressed by a pressing plate 48, and a 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.

The friction force between the friction plate 44 and the operation plate 31 rotates the operation plate 31 when the support shaft 32 rotates, but does not apply an excessive force to the main shaft 32 when the operation plate 31 is rotated. It is about.

Therefore, the operation device 30 operates as follows. When the main shaft 32 is swung by the motor 43, the operation plate 31 is moved through the frictional force of the friction plate 44.
Swings. 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 shift lever 15 swings together with the operation plate 31, the driver can observe the behavior of the manual shift lever 15 with the naked eye or with the feeling of the left hand while in the cab.
It is possible to know that the deceleration operation has been performed. This means
The same applies to the deceleration operation and the return operation.

On the other hand, when the manual shift lever 15 is manually operated, the operation plate 31 is directly moved, and the output side link 36 swings. And the movement of this operation plate 31
The slip is not transmitted to the main shaft 32 by the sliding of the friction plate 44. Therefore, the worm 42 and the wheel 3
9 does not damage the gear train and the motor 43 whose rotation from the gear side is locked.

In FIGS. 2 and 3, reference numeral 51 denotes a connecting plate connected to the lower end of the operation plate 31, on which pins 52 are implanted. On the other hand, 53 is a rotational position sensor such as a potentiometer, and its actuator 54 is
2 is in contact. Therefore, when the operation plate 31 swings, the position is detected by the potentiometer 52, and the current shift position can be grasped.

Next, an overload control method according to the present invention will be described with reference to FIG. In the present embodiment, the rated value of the engine speed, that is, the speed during the rated automatic operation is, for example, 28
Assuming 00 rpm, the reference value is 2700 rpm, and the engine load factor is 95%. Whether the work is the constant speed operation is determined based on the detection signal of the vehicle speed sensor 26. Then, the engine speed falls below 2700 rpm (step 10).
1) If the engine load factor exceeds 95% (step 102), the first determining means determines that an overload state has occurred.
This determination is made based on the load sensor 24 and the rotation speed sensor 25 of the engine 13.

When it is determined that the vehicle is in the overload condition, a control signal is output (step 103), and the motor 43 of the operating device 30 is driven to decelerate the hydrostatic transmission 14. As shown in FIG. For example, the vehicle speed is reduced by 15%. Also, during this deceleration operation, a red third lamp is output by a control signal.
27c is blinking and illuminated to draw more operator attention. Therefore, the operator can manually reduce the vehicle speed. As a result, the combine enters a state of running at a reduced speed (step 104).

As described above, the load is reduced by lowering the vehicle speed, and when the overload state is eliminated (step 105), the motor 43 of the operating device 30 is reversed by the control signal from the controller 20, and the static hydraulic pressure is reduced. The transmission 14 is returned to the original rated speed. Then, the combine returns to the rated automatic operation (step 107), and the monitor lamp 27 also turns on the second yellow lamp 27b.

When the second determining means determines that the load is still excessive at the step 105, the buzzer 27d sounds and a warning is issued (step 108).
At this time, the driver only has to operate the manual operation lever 15 in the deceleration direction, whereby the overload that cannot be eliminated even by the 15% deceleration can be eliminated.

While the automatic overload control is performed as described above, the manual shift lever 15 moves to easily notify the operator of the overload state. Also, it is of course possible to eliminate the load by manually operating the manual shift lever 15 separately from the automatic control system.

[0031]

According to the first aspect of the present invention, in the overload state, the forward speed of the combine is automatically reduced to eliminate the overload, and when the overload is eliminated, the forward speed of the combine is automatically reduced. Is returned to rated operation, thus automatically overloading and preventing damage to the combine. Then, when the vehicle is overloaded and automatically decelerated, the manual shift lever moves in the same manner as when the operator intentionally moves to the deceleration position, so that the operator can intuitively recognize that the deceleration operation has been performed. According to the second aspect of the present invention, since the one-way transmission mechanism uses the spring-biased friction plate, the setting and adjustment of the frictional force can be accurately performed, and the force transmission blocking action is reliable. According to the third aspect of the present invention, it is possible to easily know that the vehicle is decelerating due to an overload state and that the vehicle has returned to the rated operation by turning on the monitor lamp. According to the fourth aspect of the present invention, the buzzer sounds when the overload is not eliminated even after the automatic deceleration operation for eliminating the overload is performed. Can be reliably eliminated.

[Brief description of the drawings]

FIG. 1 is a block diagram of an overload prevention device according to an embodiment of the present invention.

FIG. 2 is a front view of a main part of the operation device 30.

FIG. 3 is a cross-sectional view of the operation device 30.

FIG. 4 is a flowchart of overload control according to 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 transmission lever 20 controller 27 monitor lamp 30 operating device 43 motor

Claims (4)

[Claims] 1. The running of the combine and the operation of the threshing unit are performed by a common engine, the rated output of the engine is set to a rotational speed slightly exceeding the rotational speed at the maximum output, and work is performed at the rated rotational speed. Even if the load increases or decreases to some extent, the engine speed is controlled so that the rated engine speed is maintained, and this engine output is transmitted to the vehicle body traveling device via a hydrostatic transmission. Determining means for determining whether or not an overload state in which the engine load is equal to or less than a reference value lower than the rated speed and the engine load is equal to or more than the reference value; and in the overload state, the hydrostatic transmission is operated to a deceleration position. A controller comprising control signal generating means for returning to the original rated position when the overload condition is resolved; mechanical output means for operating the internal transmission mechanism of the hydrostatic transmission; A manual transmission lever provided in the driver's seat, an automatic transmission unit which is automatic input means and is driven by a control signal from the controller, and transmits the movement of the manual transmission lever to the mechanical output means. An overload prevention device for a combine, comprising: an operating device having a one-way transmission mechanism for transmitting the movement of the automatic transmission unit to the mechanical output unit and the manual transmission lever without transmitting the transmission to a transmission unit. 2. A gear train for transmitting an output of a motor, a main shaft rotated by the gear train and directly connected to an output side link, and a spring bias for connecting the transmission lever to the main shaft. The overload prevention device for a combine according to claim 1, comprising a friction plate provided. 3. The system according to claim 1, wherein the overload control device turns on a monitor lamp while the hydrostatic transmission is being operated to a deceleration position and a return operation to a rated position. The overload prevention device for a combine according to claim 1 or 2. 4. The overload prevention device further comprises a second determination means for determining whether or not the combiner is still in an overload state when the combine is brought into a deceleration operation state by the deceleration operation.
The overload prevention device for a combine according to claim 1, 2 or 3, wherein the buzzer is sounded while the determination means determines that the overload has occurred.