JPS622986Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a combine harvester equipped with a grain culm cutting height adjustment device, specifically a hydraulically operated cutting height adjustment device that moves the reaping device up and down to adjust the grain culm cutting height. The present invention relates to a combine harvester equipped with an automatic control device that operates the cutting height adjustment device to automatically control the cutting height.

Generally, when reaping and threshing work is performed using this type of combine harvester, the reaping device is lowered to the reaping position, and at this reaping position, the reaping device is adjusted up and down using a hydraulic reaping height adjustment device to adjust the reaping height of the grain culm. When turning at the edge of a field, the reaping device is raised upwards to the storage position, and after turning is lowered to continue the reaping and threshing operation.

Therefore, when adjusting the cutting height at the cutting position, the cutting height can be adjusted more accurately at a slow speed, and when moving up to the storage position or lowering from the storage position, it can be adjusted at a faster speed. It is desirable to raise and lower it.

Therefore, the present invention provides an electromagnetic flow control valve in the hydraulic control system of the cutting height adjustment device of the reaping device, and also provides a position detection device that increases or decreases the current value depending on the vertical position of the reaping device. The detection device detects the vertical position of the reaping device, and based on this, the control valve is controlled to adjust the flow rate proportionally, so that when the reaping device is in the reaping position, the vertical adjustment is performed at a slow speed. Also, when the reaping device was raised and lowered to the storage position, it was raised and lowered at a fast speed.

By the way, the viscosity of the hydraulic oil that operates the reaping device changes with temperature changes. Therefore, for example, when reaping and threshing work is performed at low temperatures, the viscosity of the hydraulic oil increases and the overall lifting speed of the reaping device is reduced. Especially when adjusting the reaping device up and down at the reaping position, the control valve is throttled and the flow rate of the hydraulic oil is small, and the viscosity of the hydraulic oil is high, making it difficult to adjust the reaping device up and down. It is. In addition, at high temperatures, the viscosity of the hydraulic oil decreases, so the overall lifting speed of the reaping device becomes faster, and especially when the reaping device is moved up and down to the storage position, the control valve is opened and the viscosity of the hydraulic oil decreases. Because of its small size, the lifting speed becomes extremely fast, which is extremely dangerous.

However, the present invention was devised to solve these problems as well, and it is possible to accurately adjust the reaping device at a constant slow speed in the reaping position without being affected by temperature changes, and to store the reaping device at a constant slow speed. This is done to allow the robot to move up and down to a certain position at a constant, fast speed.

More specifically, an electromagnetic flow control valve 29 is interposed in the hydraulic circuit 6 of the mowing height adjustment device 7, and the operating speed of the mowing height adjustment device 7 is controlled by adjusting the flow rate by the flow rate control valve 29. As you accomplish this,
The vertical position of the reaping device 4 is detected, and based on the detection signal, the flow rate control valve 29 is operated to adjust the flow rate, and the operating speed of the mowing height adjustment device 7 is slowed near the reaping position and then stored. A position detection device 30 that controls the position so as to be faster near the position, detects the oil temperature in the hydraulic circuit 6, operates the flow rate control valve 29 based on the detection signal to adjust the flow rate, and adjusts the cutting height. This system is characterized in that an oil temperature detection device 31 for controlling the operating speed of the device 7 to be constant with respect to changes in oil temperature is interposed in the power supply side circuit 16 of the automatic control device 8.

The combine harvester of the present invention will be explained below with reference to the drawings.

In the figure, reference numeral 1 denotes the body of a combine harvester, which is equipped with a traveling device 2 at the bottom, a threshing device 3 at the top, and a reaping device 4 at the front of the body 1.

The reaping device 4 has a hydraulic elevating mechanism 5 interposed between the reaping device 4 and the machine body 1, and a hydraulic circuit 6 that controls the vertical movement of the elevating mechanism 5. An adjustment device 7 is provided.

As shown in FIG. 2, this mowing height adjustment device 7 includes an automatic control device 8 that automatically detects the height of the reaping device 4 above the ground and controls the adjustment device 7, and an automatic control device 8 that controls the adjustment device 7 by manual operation. Manual operating device 9 to control
are connected to each other.

The automatic control device 8 includes a mowing height detection device 10 of the reaping device 4, which is composed of an upward movement photo interrupter 10a and a downward movement photo interrupter 10b provided on the lower machine frame of the reaping device 4, and a cutting height detection device 10 of the reaping device 4, which is provided in the lower machine frame of the reaping device 4. Smoothing circuit 1 connected to each
1, 11, logic judgment circuit 12, and judgment circuit 1
2, and a downward movement switching circuit 14 connected to the judgment circuit 12 in parallel with the switching circuit 13. When an upward movement signal is output from the detection device 10, , operates the cutting height adjustment device 7 via the logic judgment circuit 12 and the switching circuit 13 to move the reaping device 4 upward, and when the detection device 10 outputs a downward movement signal, the logic judgment circuit 12 and The adjustment device 7 is operated via the downward movement switching circuit 15 to cause the reaping device 4 to move downward.

Each of the smoothing circuits 11 smoothes the signal from the detection device 10 to prevent malfunctions caused by footprints in the field, stubble, etc. It is determined whether the automatic state or the manual state should be set based on input signals from the R.S.F.F circuit and the like, which will be described later.

The automatic control device 8 includes each switching circuit 1
3 and 14 are connected to the power supply 15 via a first connection circuit 16, and the cutting height detection device 10 is connected to the power supply 15 via a second connection circuit 17 branched from the first circuit 16. The judgment circuit 12 is connected to the power supply 15 via a third connection circuit 18 branched from the first circuit 16, and a key switch 19 and a fuse 20 are interposed on the power supply 15 side of the first circuit 16. A threshing switch 21 and an automatic switch 22 are interposed in the third circuit 18.

The manual operating device 9 also includes a manual switch 23 for upward movement and a manual switch 24 for downward movement,
By operating these switches 23 and 24, the cutting height adjusting device 7 is operated to manually move the cutting device 4 up and down.

The manual switches 23 and 24 and the logic judgment circuit 1
2, the inverter 25 and R・S・F・F
(Reset/Set/Flip/Flop) circuit 26 is interposed to give priority to the output signal from the detection device 10 at the time of output associated with the operation of each of the switches 23 and 24, and the mowing height adjustment device 7 should be operated manually.

The inverter 25 inverts the input signal and outputs it, and the R・S・F・F circuit 2
Reference numeral 6 sets the output signal to high level or low level with respect to the input signal.

Further, between the R・S・F・F circuit 26 and the logic judgment circuit 12, the manual switches 23, 24
Two interlocking switches 27a and 27b, which are turned off when the switches 23 and 24 are turned on and turned on when they are turned off, and an automatic return switch 28 are interposed, and the automatic return switch 28 is operated. Accordingly, the manual switches 23 and 24 are released, and the automatic control device 8 automatically controls the cutting height adjustment device 7.

However, the present invention has the above configuration,
The mowing height adjusting device 7 is configured to operate at a slow speed when the reaping device 4 is at the reaping position, and to operate at a high speed when the reaping device 4 is above the reaping position.

Specifically, the hydraulic circuit 6 of the cutting height adjustment device 7
As shown in FIG. 3, an electromagnetic flow control valve 29 is installed to change the flow rate of hydraulic oil supplied to the lifting mechanism 5 in proportion to changes in current, and a solenoid 29a for vertical movement of this control valve 29 is installed. ,29
b is connected to vertical movement switching circuits 13 and 14 in the control circuit shown in FIG.

The reaping device 4 is also equipped with a position detecting device 30 (hereinafter simply a potentiometer) mainly consisting of a potentiometer, which detects the positional fluctuation of the reaping device 4 and changes the current value (substantially the resistance value) based on the detected value. a meter) is provided, and the meter 30 is interposed in the first connection circuit 16 in the control circuit of FIG.
The resistance value of the meter 30 changes due to the positional change of the reaping device 4, thereby changing the current value flowing through each solenoid 29a, 29b of the control valve 29, and based on this, the throttling amount of the control valve 29, that is, the hydraulic oil. This is done to adjust the amount of outflow.

That is, when the reaping device 4 is in the reaping position below the machine body, the resistance value of the meter 30 is made small;
By increasing the current flowing through each solenoid 29a, 29b of the control valve 29, the amount of throttling of the control valve 29 is increased, that is, the amount of hydraulic oil flowing out from the control valve 29 is decreased, and the cutting height adjustment device 7 is adjusted. The operating speed is slow, and when the reaping device 4 is above the reaping position, the meter 30
The resistance value of each solenoid 29 is set to be large.
a, 29b is reduced, and the control valve 2
This is done in order to increase the operating speed of the adjusting device 7 by reducing the amount of throttle 9, that is, increasing the amount of hydraulic oil flowing out from the control valve 29.

Further, a hydraulic oil temperature detection device 31 is provided in the hydraulic circuit 6.
The detection device 31 is installed in the first circuit 16 in the control circuit in series with the meter 30, and the throttle amount of the control valve 29 is adjusted based on the temperature detected by the detection device 31. It is eggplant.

That is, as the detection device 31, a thermistor or the like whose resistance value changes depending on changes in oil temperature is used, and when the hydraulic oil in the hydraulic circuit 6 is high temperature and has a low viscosity,
The current flowing through each solenoid 29a, 29b of the control valve 29 is made large by making the resistance value small, and the amount of throttling of the control valve 29 is made large, and when the hydraulic oil is low temperature and has a high viscosity, the resistance value is made large. Therefore, the current flowing through each solenoid 29a, 29b is made small, and the amount of throttle of the control valve 29 is made small, so that the operating speed of the adjusting device 7 is always kept constant regardless of the hydraulic oil temperature. It is.

The present invention is constructed as described above, and for automatic reaping and threshing work of a combine harvester, the reaping device 4 is located at the reaping position below the machine body, and the reaping height detection device 1
0, the cutting height of the reaping device 4 is detected, and the output signal from the detection device 10 causes the automatic control device 8 to operate the cutting height adjusting device 7, and the control valve 29 is activated.
As a result, the lifting mechanism 5 is adjusted in the vertical direction, and the reaping device 4 is automatically controlled.

When the reaping device 4 is in the reaping position as described above, the resistance value of the potentiometer 30 is small and the current flowing through each solenoid 29a, 29b of the control valve 29 is large, so that the throttle amount of the control valve 29 is large. Therefore, the adjustment of the lifting mechanism 5, that is, the traveling device 4, is performed at a slow operating speed.

Furthermore, when the combine harvester is turned at the edge of a field, the reaping device 4 is raised upward from the reaping position to the storage position, and then lowered again after turning. At this time, the resistance value of the potentiometer 30 is becomes large and the current flowing through each of the solenoids 29a and 29b becomes small, so the amount of restriction of the control valve 29 becomes small, and the adjustment of the lifting mechanism 5, that is, the traveling device 4, is performed at a fast operating speed. be.

Furthermore, the viscosity of hydraulic oil changes depending on the temperature, and the viscosity is small at high temperatures and large at low temperatures.The temperature of the hydraulic oil is detected by the oil temperature detection device 31, As the resistance value becomes smaller, each solenoid 2 of the control valve 29
The current flowing through 9a and 29b becomes large, and the control valve 2
Also, when the hydraulic oil is at a low temperature, the resistance value of the detection device 31 becomes large, and the current flowing through each of the solenoids 29a and 29b becomes small, so that the amount of throttling of the control valve 29 becomes large. In other words, the control valve 29 becomes smaller depending on the viscosity of the hydraulic oil.
Therefore, the operating speed of the adjusting device 7 is not affected by changes in the viscosity of the hydraulic oil, and the operating speed is controlled according to the usage condition of the reaping device 4.

As explained above, the present invention is not affected by changes in temperature or viscosity of the hydraulic oil.
The reaping device can be adjusted at a constant slow speed in the reaping position, and the reaping device can be raised and lowered to the storage position at a constant fast speed, so that when adjusting the reaping device in the reaping position, adjustment becomes difficult. This eliminates the danger of raising and lowering the reaping device to its storage position, allowing for safe and accurate adjustment of the reaping device.Moreover, the reaping device adjusts its operating speed according to the usage conditions. This made it extremely convenient for combine harvester operations.

[Brief explanation of the drawing]

Figure 1 is a slope view of the combine harvester according to the present invention.
FIG. 2 is a control circuit diagram of the cutting height adjustment device, and FIG. 3 is a circuit diagram of the same adjustment device. 4... Reaping device, 6... Hydraulic circuit, 7... Cutting height adjustment device, 29... Electromagnetic flow control valve, 30...
...Position detection device, 31...Oil temperature detection device.

Claims (1)

[Scope of utility model registration request] The automatic system is equipped with a hydraulically operated cutting height adjustment device 7 that moves the reaping device 4 up and down to adjust the cutting height of the grain culm, and automatically controls the cutting height by operating the cutting height adjustment device 7. In a combine equipped with a control device 8, an electromagnetic flow control valve 29 is interposed in the hydraulic circuit 6 of the cutting height adjustment device 7, and the flow rate adjustment by the flow control valve 29 controls the cutting height adjustment device 7. The reaping device 4 is configured to control the operating speed.
Detects the up and down position of , and operates the flow rate control valve 29 based on the detection signal to adjust the flow rate, and the operating speed of the cutting height adjustment device 7 is slow near the reaping position and fast near the storage position. The position detection device 30 detects the oil temperature in the hydraulic circuit 6 and controls the flow rate control valve 29 based on the detection signal.
The cutting height adjusting device 7 is operated to adjust the flow rate.
A grain culm cutting height adjusting device characterized in that an oil temperature detecting device 31 for controlling the operating speed of the grain culm so as to be constant with respect to changes in oil temperature is interposed in the power supply side circuit 16 of the automatic control device 8. Combine harvester equipped.