JPH0437686B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Technical Field The present invention relates to a combine harvester equipped with a threshing device that travels around a farm to harvest grain, and an engine that drives both the traveling device and the threshing device of this combine. Regarding the control mechanism.

(b) Summary of the Invention In order to easily improve the processing accuracy and work efficiency of the threshing device, the engine control mechanism for a combine harvester according to the present invention uses a fuel supply means so that the engine rotational speed becomes a set rotational speed. The engine is controlled so as to maintain the set rotational speed and produce the maximum output by including a means for operating the engine and a means for controlling the vehicle speed so that the output of the engine becomes the maximum output.

(c) Prior art and its disadvantages The threshing device mounted on a combine rotates a threshing barrel equipped with a large number of threshing teeth on the outer periphery in a threshing chamber, and converts cut culm waste into grains and culm waste. To separate. The rotation speed of this cylinder greatly affects the processing accuracy, such as the quality of the separation and damage to the grains.
It must be determined based on the crop variety and reaping conditions such as the wet and dry conditions of the culms. Further, the amount of culms introduced into the husking chamber is approximately proportional to the traveling speed of the combine harvester during reaping work, and becomes a load on the engine.
Furthermore, in a combine harvester, the traveling device and the threshing device are generally driven by a single engine. For these reasons, in order to thresh the harvested culms with high precision, the rotational speed of the engine and the vehicle speed must be set appropriately.

For this reason, in the past, the reaping operation was started with the amount of fuel supplied fixed so that the maximum output could be obtained at a predetermined set rotation speed. However, it has not been possible to deal with the case where the reaping conditions change during the reaping operation and the load on the engine changes. That is, when the load is small, the engine speed increases, while when the load increases, the engine speed decreases. For this reason, there was a drawback that the rotation speed of the threshing barrel of the threshing device changed and the processing accuracy decreased. In order to compensate for this, it is necessary to appropriately change the fuel supply amount and vehicle speed, but this operation is a frequent task that requires a high level of skill gained through experience, and an operator with ordinary skill can accurately change the fuel supply amount and vehicle speed. In some cases, the machine could not be operated properly, resulting in decreased work efficiency and wasted fuel.

(d) Purpose of the Invention In view of the above-mentioned conventional drawbacks, the purpose of the present invention is to be able to control the engine so that maximum output is maintained while maintaining the set number of circuits even when the load or vehicle speed changes, and to improve the processing accuracy of the threshing device. Another object of the present invention is to provide an engine control mechanism for a combine harvester that can easily improve work efficiency.

(e) Structure and effect of the invention The engine control mechanism of the combine of this invention is as follows:
A rotation speed control means that determines the operation of the fuel supply means so that the engine rotation speed becomes the set rotation speed based on the current rotation speed of the engine and the set rotation speed determined by the reaping conditions, and a maximum rotation speed at the set rotation speed. Based on the difference between the amount of fuel supplied to obtain output and the amount supplied when controlling the fuel supply means, the operation of the vehicle speed changing means is controlled to adjust the load so that the engine output reaches the maximum output at the set rotation speed. A vehicle speed control means is provided.

According to the present invention, with the above configuration, the fuel supply means can be operated by the vehicle speed control means so that the engine speed reaches the set rotation speed, and the vehicle speed control means can operate the fuel supply means so that the engine output reaches the maximum output. Vehicle speed can be controlled.

When the reaping operation is started after the rotation speed has been controlled to the set rotation speed in a no-load state, a load is applied to the engine from the traveling device and the threshing device. As a result, the engine rotation speed decreases, but the rotation speed control means operates the fuel supply means to increase the amount of fuel supplied so as to maintain the set rotation speed. Thereafter, the vehicle speed is increased by the operation of the vehicle speed control means until the load matches the maximum output at the set rotation speed, and the rotation speed control means repeatedly controls the operation of the fuel supply means. Therefore, the maximum output can be exerted while maintaining the set rotational speed determined by the reaping conditions, so it is possible to improve the processing accuracy and work efficiency of the threshing device.

(f) Embodiment i Structural Description FIG. 2 is a block diagram of a control section of a combine harvester in which an engine control mechanism according to an embodiment of the present invention is used.

The CPU 21 is connected via an I/O interface 24 to a gear lever motor drive relay 25, an accelerator motor drive relay 26, and a timer/counter 2.
7, an A/D converter 28 and a switch unit 17 are connected. Shift lever motor drive relay 25
is connected to the speed change lever motor 12. The rotation shaft of this speed change lever motor 12 is the speed change lever 11
It is the fulcrum of the The operation of the gear shift lever 11 is transmitted to the hydraulic transmission 2 via the link mechanism 11a. The hydraulic transmission 2 transmits the rotation of the crankshaft of the engine 1 to the gear transmission 3. The hydraulic transmission 2 and the gear transmission 3 constitute a continuously variable transmission which is a transmission.

An electromagnetic pickup 5 is provided facing a flywheel 4 fixed to the crankshaft of an engine 1. This electromagnetic pickup 5 detects the rotation of the flywheel 4 and outputs an output signal to the timer/counter 27. Further, a vehicle speed sensor 6 is provided on the first shaft of the gear transmission 3. The output signal of this vehicle speed sensor 6 is output to a timer count 27.

The accelerator motor 10 is connected to the accelerator motor drive relay 26 . The accelerator 9 is attached with the rotation axis of the accelerator motor 10 as a fulcrum. The operation of the accelerator 9 is transmitted to the governor 1a, which is a fuel supply device, via a link 9a. Also, the accelerator 9 has a potentiometer 9b.
is provided, and an output voltage corresponding to the position of the accelerator 9 is output to the A/D converter 28. Switch part 1
7 is a threshing switch 1 that detects whether or not the driving force of the engine 1 is being transmitted to the threshing barrel of the threshing device.
3, and variety switches 14 to 16 for selecting the crop variety to be harvested.

The ROM 22 connected to the CPU 21 stores the rotational speed of the engine 1 specified by each crop variety, the output characteristics of the engine 1 shown in FIG. The relationship with rotation speed, etc. are stored. Also RAM
23 temporarily stores input and output data.

DESCRIPTION OF OPERATION FIGS. 1A and 1B are flowcharts showing the operation of the engine control mechanism of the combine harvester.

After the engine is started, when the automatic control mode of the engine is set by operating the threshing switch 13 or the like, the timer/counter 27 starts counting down a predetermined period of time. Step n1 (hereinafter referred to as “Step n”)
” is simply referred to as “n”), when the time Ta has elapsed, the process advances to n2, reads out which switch is being operated among the variety switches 14 to 16 of the switch section 17, and sets the rotation speed according to the selected crop variety. Rs is retrieved from the ROM 22 and stored in the memory area M1 of the RAM 23 shown in FIG.
Next, in n3, the current vehicle speed is determined from the output value of the vehicle speed sensor 6.
Sa is calculated and stored in memory area M2. Furthermore, in n4, the current rotation speed Ra is calculated from the output value of the electromagnetic pickup 5 and stored in the memory area M3.
At n5, the output value of the potentiometer 9b is A/D converted and stored in the memory area 4 as the current fuel supply amount Aa.

When the time Tb elapses at n6, the engine speed difference Rd is calculated at n7. This rotational speed difference Rd is the difference between the set rotational speed Rs and the current rotational speed Ra. Next, in n8, it is determined whether the rotational speed difference Rd is positive or negative. n8
If the rotational speed difference Rd is a positive number in
n10 sets the contents of flag B, and if the rotation speed difference Rd is a negative number, n9 sets the contents of flag A by 1.
and proceed to n11. At n11, the absolute value of the rotational speed difference Rd is compared with the tolerance k of the set rotational speed Rs. The engine control mechanism of the present invention basically controls the engine rotation speed to match the set rotation speed Rs suitable for each crop variety, but it is difficult to strictly match the two. Moreover, such a control operation lacks stability. Therefore, a dead zone as a permissible error is provided in the set rotation speed Rs within a range of ±k, and the engine speed is controlled so as to fall within the range of this dead zone.

If the absolute value of the rotational speed difference Rd is larger than the error k at n11, it is determined that the current rotational speed Ra is not within the dead zone, and the drive output value T of the accelerator motor 10 is calculated at n14. This output value T is determined according to the magnitude of the absolute value of the rotation speed difference Rd.
The memory area M5 is assigned to a counter C for driving the accelerator motor, and at n15, the contents of this counter C are set to the output value T obtained by calculation. Next, in n16, the maximum fuel supply amount Am to obtain the maximum output at the set number of circuits Rs is determined by ROM2.
2 is stored in memory area M6 calculated from the engine output characteristics stored in No.2. Furthermore, the supply amount difference Ad is calculated in n17. This supply amount difference Ad is the difference between the maximum supply amount Am and the current supply amount Aa.

At n18, it is determined whether the supply amount difference Ad is positive or negative.
If the supply amount difference Ad is a negative value at n18,
In n19, the content of flag C is set to 1, and if the content of supply amount difference Ad is a positive value, the content of flag D is set to 1 in n20, and the process proceeds to n21. At n21, the accelerator motor 10 is driven. At this time, the driving direction is determined by referring to the contents of flags A and B in memory areas M7 and M8. That is, when the content of flag A is 1, the reversing relay of the accelerator motor drive relay 26 is turned on, and the accelerator motor 10 is rotated in a direction to decrease the supply amount. On the other hand, when the content of flag B is 1, the reversing relay is turned off and driven in the direction of increasing the amount of fuel supplied.

When the time Tc has elapsed at n22, the process proceeds to n23, where the speed change lever motor 12 is driven. Flag C assigned to memory areas M9 and M10 at this time
The rotation direction of the speed change lever motor 12 is determined with reference to the contents of the flag D. That is, when the content of flag C is 1, the reversing relay of the speed change lever motor drive relay 25 is turned on, and the speed change lever motor 12 is driven to move the speed change lever 11 in the deceleration direction. On the other hand, when the content of flag D is 1, the reversing relay is turned off and the speed change lever 11 is driven to move in the speed increasing direction. When the speed change lever motor drive operation of n23 is completed, it returns to n1 and is in operation to control the engine speed.
The n23 main routine is repeated.

During the operation of this main routine, the current engine speed Ra and the current vehicle speed Sa are determined by counting the number of pulses detected within a predetermined time period from the electromagnetic pickup 5 and the vehicle speed sensor 6, respectively, by the timer/counter 27. At n1, time Ta is measured as a reference time for counting the number of pulses. If the time Ta has not elapsed at n1, the process advances to n6. Further, if the time Tb has not elapsed in n6, the process advances to n22. To determine the passage of time Tb and Tc at n6 and n22 is
This is to reduce the load on the CPU. If the absolute value of the rotation speed difference Rd is smaller than the tolerance k at n11, the process advances to n12 and the contents of the counter C are set to 0.
and stop the motor drive with n13.

A timer 29 is connected to the CPU 21,
The time is approximately 1/100 of the time required for one operation of the main routine. When the timer 29 times up, a signal is output to the CPU 21, which causes the CPU 21 to execute a timer interrupt routine. That is, at n24, it is determined whether the contents of the counter C in the memory area M5 are 0 or not, and if not, the contents of the counter C are decremented by 1 at n25. Alternatively, if the content of the counter C is 0, the drive of the accelerator motor 10 is stopped at n26 and the process returns to the main routine. At n14, the output value T of the drive of the accelerator motor 10 is calculated using the amount of rotation of the motor during the time measured by the timer 29 (timer interrupt period) as one unit. Therefore, each time the timer 29 times up, the accelerator motor can be rotated by the required amount by decrementing the contents of the counter C by 1 in steps n24→n25.

The above operation will be specifically explained using the diagram shown in FIG. 3 showing the output characteristics of the engine. Now set rotation speed
When Rs is 3000 rpm, accelerator 9 is in an unloaded state before the combine starts traveling.
It is located at position 9d with a supply amount that can achieve 3000 rpm. When the combine starts running and begins reaping work, the load increases due to road resistance and threshing work, and the engine speed decreases, progressing from n7 → n8 → n10.
When the engine speed decreases further and exceeds the dead zone range, it progresses from n11 to n14, and by n8 to n10, n14, and n21, the accelerator 9 moves from the position of 9d to the arrow
direction to the position corresponding to the no-load rotation speed of the output curve that satisfies the current output value at 3000 rpm. For example, as the load increases, the output decreases.
When it rises to P1, the set rotation speed Rs is 3000rpm.
The output line CU1 that satisfies the output value P1 is used. No-load rotation speed of this output line CU1
The accelerator motor 10 is driven to move the accelerator 9 to a position 9e corresponding to 3050 rpm. This maintains the engine speed at 3000 rpm.

What is the maximum supply amount of accelerator Am in n16?
Output line that satisfies maximum output Pm at 3000rpm
This is the amount of fuel supplied to achieve CUm, and corresponds to 3200 rpm in a no-load state. In other words, if more fuel is supplied, the engine speed will reach the set speed.
In other words, it means that the supply amount is enough to move the axle 9 to the position 9c corresponding to the no-load state of the output line CUm. Also, in this state, the load can be increased to the maximum output Pm at 3000 rpm. Therefore, when the supply amount difference Ad is a positive value, there is a margin in the output, and it is possible to increase the load by increasing the moving speed of the combine harvester. Therefore, the speed change lever motor 12 is driven in the speed increasing direction at n23. However, the maximum speed of a combine harvester suitable for threshing is approximately 1.1 m/s, and the vehicle speed is controlled so as not to exceed this value during threshing.

Even if the vehicle speed of the combine is below the maximum speed for threshing, the load may change to the maximum output P depending on the condition of the thick culm.
It may exceed m. In this case, the supply amount difference Ad becomes 0 or a negative number at n18, so the process proceeds to n19.
As a result, the reversing relay is turned on when the gear shift lever motor 12 of n23 is driven.
is driven in the deceleration direction and controlled to reduce the load.

When crop conditions change and the load decreases during reaping work, the accelerator 9 is moved by arrow Y to the position corresponding to the rotation speed of the output line under no load, which satisfies the reduced output at 3000 rpm by the operation of n8→n9 and n21.
direction to reduce the amount of fuel supplied. Also, if there is enough running speed, n16→n17→n18→n20
And the operation of n23 increases the running speed and increases the load.

The above n7 to n10, n21, n24 to n26, the accelerator motor 10 and the accelerator motor drive relay 26 correspond to the rotation speed control means of the present invention, and n16 to n20,
n23 and the speed change lever motor drive relay 25 of the speed change lever motor 12 also correspond to vehicle speed control means.

Effects of the Embodiment As described above, according to this embodiment, the accelerator is operated by the rotation speed control means so that the engine rotation speed always falls within the allowable range of the set rotation speed, and the processing accuracy of the threshing device is improved. can do. Along with the operation of the rotation speed control means, the vehicle speed change means is operated by the vehicle speed control means so that the engine output becomes the maximum output. This makes it possible to harvest as many culms as possible while maintaining the processing accuracy of the threshing device, thereby improving work efficiency.

Other aspects In this example, the set rotation speed of the engine is determined only by the crop variety, but it is possible to input other reaping conditions such as the wet and dry state of the culm, so that the set rotation speed of the engine can be set based on multiple conditions. It is also possible to determine the number of rotations. Further, in this embodiment, a continuously variable transmission was constructed using a hydraulic transmission, but the present invention can also be implemented in a combine harvester having a stepped transmission with a gear transmission to improve processing accuracy and work efficiency. be able to.

[Brief explanation of drawings]

1A and 1B are flowcharts showing the operation of the engine control mechanism of a combine harvester according to an embodiment of the present invention, FIG. 2 is a block diagram of the control section of the engine control mechanism of the combine, and FIG. FIG. 4 is a diagram showing a part of the memory map of the memory included in the control section. 1a... Governor (fuel supply means), 2... Hydraulic transmission (vehicle speed changing means), 3... Gear transmission (vehicle speed changing means), 9...
Accelerator (fuel supply means), 10...accelerator motor (rotation speed control means), 11...shift lever (vehicle speed changing means), 12...shift lever motor (vehicle speed control means), 25...shift lever motor drive relay (vehicle speed control means), 26...Accelerator motor drive relay (rotation speed control means).

Claims (1)

[Scope of Claims] 1 The traveling device and the threshing device are driven by a single engine, and the fuel supply means adjusts the engine rotation speed by changing the fuel supply amount, and the engine rotation is controlled via a transmission device. In the engine control mechanism of a combine, the engine control mechanism for a combine is equipped with a vehicle speed change means for transmitting a vehicle speed to a traveling device. A rotation speed control means determines the operation of the fuel supply means so that the engine output reaches the set rotation speed based on the difference between the amount of fuel supplied to obtain the maximum output at the set rotation speed and the amount supplied when controlling the fuel supply means. An engine control mechanism for a combine harvester, comprising: a vehicle speed control means for controlling the operation of a vehicle speed changing means in order to adjust the load so that maximum output can be produced.