JPS6338165B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a load control device used in a mobile agricultural machine such as a combine harvester.

In the working section of a combine harvester, for example, the load on the threshing section tends to vary greatly depending on the working environment in the handling room. Therefore, conventionally, this type of load control device detects the load in the handling chamber using a load detection device such as a rotation sensor or a torque sensor connected to the handling cylinder in the handling chamber, and then automatically speeds up based on the detected signal. By controlling the transmission mechanism and changing the traveling speed according to the size of the load,
There are some that are designed to keep the load on the handling room appropriate.

However, with such conventional load control devices, when the side clutch (steering clutch) associated with the traveling gear is disengaged during driving work, the load increases, the engine speed decreases, and the load increases. I had the inconvenience of slowing down just as I had done before.

The present invention has been made in view of the above points, and its purpose is to provide a load control device for mobile agricultural machinery that can maintain the working speed at the previous speed without changing the working speed when the load of the working machine suddenly changes. It is about providing.

Hereinafter, the present invention will be explained in detail based on examples.

FIG. 1 is a perspective view of a combine harvester equipped with an embodiment of a load control device according to the present invention. In the figure, 1 is a body mounted on the upper part of the traveling device 10,
Reference numeral 2 denotes a reaping work section attached to the front of the machine body 1, and this reaping work section 2 consists of a weeding rod 3 protruding from the rear of the lower part, and a weeding workpiece 4 fixed to the tip of the weeding rod 3.
and a pulling device 5 provided above the weeding body 4;
It consists of a grain culm conveying device 6 that sends the grain culm cut upward by a reaping section provided near the base of the dividing rod 3, and the like. Reference numeral 7 designates a threshing conveyance chain for supplying grain rods to a threshing section housed inside the machine body 1, 8 a threshing cover, and 9 an entrance to the threshing section.

Further, 10 is a traveling device driven by a commonly known speed change mechanism, 11 is a speed change lever associated with the speed change mechanism, and a pulling device 5
The driving speed of the traveling device 10 is changed in accordance with manual operation thereof or automatic operation based on a signal output from a control unit described later. ing. Reference numeral 13 denotes a load display device consisting of three indicator lights 14, 15, 16 and a protective cover 17 that houses them, in order to display the load status of the threshing section. It is installed in the upper part 5a of the lifting device 5 so that it can be seen from both the front side of the aircraft body 1 and the driver's seat 12 side, and in an area where the grass stubble 4 can be seen from the driver's seat 12. And each of the indicator lights 14, 15, 1
6 is configured to be selectively driven by a signal output from the control unit in correlation with the traveling speed to be changed. In this case, the indicator light 14 displays red, the indicator light 15 displays orange, and the indicator light 16 displays blue. All operations of the combine harvester are performed by an engine, and the reaping section 2 is connected to the engine via a reaping clutch, and the threshing section is connected to the engine via a threshing clutch. The traveling device 10 is also connected to the engine via a traveling clutch, and all other operating parts are connected to the engine via clutches and the like.

FIG. 2 is a system diagram showing an outline of a load control device which constitutes the main part of the present invention, and FIG. 3 is a block diagram of its control circuit. In FIG. 2, 21 is a handling drum of the threshing section 20 housed inside the machine body 1 shown in FIG. A rotation sensor 23 is attached. 24 is a control unit that receives the pulse signal output from the rotation sensor 23 and outputs a control signal according to the size of the load.
It is configured as shown in the figure. In FIG. 3, 25 is a frequency divider that divides the detection pulse output from the rotation sensor 23, 26 is a pulse generator that generates clock pulses P ₁ and P ₂ of different frequencies, and 27 is the frequency divider 25. A counter 28 counts the high frequency clock pulse _P1 sent from the pulse generator 26 by frequency-divided output pulses and converts the rotation speed of the rotation sensor 23 into a pulse number. A comparator 29 compares the rotation speed with a reference value set in advance and outputs overload and light load signals a and b associated with rotation based on the comparison result. a latch circuit 30 for latching the signal output from the comparator 28 due to the low frequency clock pulse P ₂ and absorbing sudden changes in the signal during the period of the clock pulse;
is a latch circuit for transferring or latching the signal output from the latch circuit 29 in response to the on/off signal of the selection switch 31;
1 is turned off when the side clutch (steering clutch) 18 shown in FIG. 2, which is related to the traveling device 10, is in the "on" position (solid line), and is turned off when it is in the "off" position (broken line). Configured to turn on. 32 is an output circuit that outputs control signals for overload, normal load, and light load according to the size of the load based on the signal output from the latch circuit 30, and these signals are shown in FIG. The signals are input to an overload display circuit 13a, a normal load circuit 13b, and a light load display circuit 13c, which constitute the load display device 13 shown. Also,
Among these signals, the overload and light load control signals are inputted to the output circuit 34 via the delay circuit 33, and the overload and light load shift signals are processed as control signals to be shifted by the output circuit 34. is supplied to drive circuits 36 and 37 for deceleration and speed increase, which constitute the hydraulic continuously variable transmission mechanism 35. This continuously variable transmission mechanism 35, as shown in FIG. By the action of the portion 38, the speed change lever 11 shown in FIG. 1 is swung back and forth to change the traveling speed of the traveling device 10.

Note that a delay time of about several seconds is set in the delay circuit 33.

Next, the operation of the above embodiment will be explained. Here, it is assumed that the switch 31 is turned off with the side clutch 18 in the "on" position. When performing a reaping operation, when the combine moves forward, the grain culms are introduced between the splitting bodies 4, are pulled up by the pulling device 5, and their roots are cut off by the reaping section. The harvested grain culms are sent upward by a grain culm conveying device 6 and transferred to a threshing conveyance chain 7. The grain culms whose roots are held by the threshing conveyance chain 7 are supplied to the threshing section through the inlet 9 and are threshed. During this threshing process, when the rotation speed of the threshing section is constant and its load is normal, the pulse signal detected by the rotation sensor 23 is divided by the frequency divider 25 and sent to the counter 27. is input. Then this counter 27
counts the clock pulse _P1 sent from the pulse generator 26 for a period corresponding to the time width of the frequency-divided output pulse, but this count value becomes approximately equal to the reference value of the comparator 28, and the comparator 28 No signal is output. Therefore, the output circuit 32 considers it to be normal and inputs the normal load control signal to the normal load display circuit 13b of the load display device 13.
b turns on the indicator light 15 (orange). If the rotational speed of the threshing section decreases, the number of pulses output from the rotation sensor 23 decreases, and the count value of the counter 27 also decreases. Then, comparator 2
8 outputs an overload signal a since the count value output from the counter 27 is less than the reference value, and this overload signal a is input to the latch circuit 29. As a result, the latch circuit 29 converts the overload signal a into a clock pulse sent from the pulse generator 26.
It is latched at timing _P2 , and this latch signal is input to the output circuit 32 via the latch circuit 30. As a result, the output circuit 32 inputs the signal latched by the latch circuit 29 as an overload control signal to the overload display circuit 13a, and also inputs it to the deceleration drive circuit 36 via the delay circuit 33 and output circuit 34. do. As a result, the overload display circuit 13
In the case of a, the indicator lamp 14 is turned on (red) at the same time as the signal arrives, whereas the deceleration drive circuit 36 decelerates the traveling speed with a delay of the time (about several seconds) set in the delay circuit 33. Thereby, the operator can know from the lighting of the indicator light 14 whether there is an overload due to the rotation of the threshing section, and the load can be appropriately controlled. Conversely, when the rotational speed of the threshing section increases, the number of pulses output from the rotation sensor 23 increases, and the count value of the counter 27 also increases accordingly. Then, this count value exceeds the reference value of the comparator 28, and the comparator 28 outputs the light load signal b, and the signal b is sent to the latch circuit 29.
Enter. As a result, the latch circuit 29 latches the input signal with the clock pulse from the pulse generator 26 in the same manner as described above, and the output circuit 32 inputs the latched signal as a light load control signal to the light load display circuit 13c. At the same time, the speed increasing drive circuit 3 is connected via the delay circuit 33 and the output circuit 34.
Enter 7. As a result, the light load display circuit 1
3c lights up the indicator light 16 (blue),
The speed increasing drive circuit 37 increases the traveling speed with a delay of the operating time of the delay circuit 33 in the same manner as described above, and as a result, the load on the threshing section is appropriately controlled.

On the other hand, in the process where the traveling speed is controlled according to the magnitude of the load, the side clutch 18
When the switch 31 is operated from the "on" position to the "off" position (as shown by the broken line in FIG. 2), the switch 31 is turned on by this operation, and a corresponding on signal is sent to the latch circuit 30. As a result, the latch circuit 30 latches the signal output from the latch circuit 29 in response to its ON signal, so that even if the side clutch 18 is disengaged, the display mode and running speed of the load display device 13 do not change. In other words, if the side clutch is disengaged during threshing, the load on the engine's output shaft will increase, and the running speed may be reduced in the same way as when the engine speed decreases and the load on the threshing section increases. However, because the latch circuit 30 can latch the signal immediately before the sudden change in load, the running speed will not change due to the sudden change in load.

In the above embodiment, the rotation sensor is attached to the input shaft of the threshing section, but the present invention is not limited to this. It is also possible to install a rotation sensor between the input shaft of a working machine such as the above, or to use a normal load detection device in addition to the rotation sensor. Further, the speed change mechanism is not limited to a hydraulic continuously variable transmission, but a power shift or the like may be used, and a load display device may also be installed at a predetermined location other than the lifting device.

Further, in the above-described embodiment, a delay circuit is provided in the control unit so that the speed control is delayed by several seconds after the load display device is turned on, but this delay circuit may be omitted. Furthermore, the present invention can also be applied to mobile agricultural machines such as tractors in addition to combine harvesters.

As described above, according to the present invention, in the load control device for a mobile agricultural machine that automatically changes the traveling speed based on the detection result of the work equipment load, when the side clutch of the traveling device is disengaged, the immediately preceding traveling speed is changed at the same time. By providing a means for holding a signal that maintains the load of the traveling equipment, it is possible to accurately detect the load fluctuation of the traveling equipment with a simple configuration since the side clutch detects the load fluctuation of the traveling equipment, and it is possible to detect sudden changes in the load of the work equipment. The running speed does not change depending on the situation, and the effect is that stable work can be carried out at all times.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a combine harvester equipped with an embodiment of a load control device according to the present invention, FIG. 2 is a system diagram showing an outline of its main parts, and FIG. 3 is a block diagram of a control circuit. 5...Lifting device, 10...Traveling device, 11...
Gear shift lever, 13...Load display device, 14,1
5, 16... Indicator light, 18... Side clutch,
20... Threshing section, 21... Handling cylinder, 22... Input shaft of threshing section, 23... Rotation sensor, 24... Control unit, 25... Frequency divider, 26... Pulse generator, 27... Counter, 28... Comparator,
29... Latch circuit, 30... Latch circuit, 31
...Switch associated with side clutch 18, 32...Output circuit, 33...Delay circuit, 34
...Output circuit, 36...Hydraulic continuously variable transmission mechanism.

Claims (1)

[Scope of Claims] 1. A load control device for a mobile agricultural machine that automatically changes the traveling speed based on the detection result of the work equipment load, which maintains the previous traveling speed at the same time as the side clutch of the traveling device is disengaged. A load control device for a mobile agricultural machine, characterized in that it is equipped with means for holding a signal. 2. The load control device for a mobile agricultural machine according to claim 1, wherein the load detection sensor for detecting the work machine load is a rotation sensor.