JPH0123231Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a lowering control device for a reaping section in a combine harvester for always maintaining an appropriate height of grain culm cutting in the reaping section.

Conventionally, in combine harvesters equipped with a reaping section lowering regulating device that sets the lowering position of the reaping section and automatically restricts its descent, the set value must be changed each time the reaping section is raised or lowered. Therefore, for example, in order to maintain the appropriate cutting height in response to the head rise of the machine at the start of reaping work, it is necessary to adjust the lowering position setting value of the reaping section each time, but the operation is complicated. I can't respond immediately.

In addition, combine harvesters equipped with a sensor that automatically controls the cutting height by making the cutting section follow irregularities in the field can accurately detect the height above the ground when mowing along a ridge. The flaw is that it tends to be cut too high.

In view of the conventional situation, the present invention is capable of regulating the descent of the reaping section using a ground height detection sensor at the start of reaping work, etc., and also allows the reaping section to be adjusted up and down to follow the unevenness of the field. However,
In the case of ridge cutting, etc., even if a control system is set in which the lowering of the reaping section can be regulated based on the detection value of the elevation position of the reaping section and its lowering position setting value, unless the reaping elevation lever is lowered, the height above the ground will be lowered. The set position of the detection sensor can be fixed at the same position without being lowered, and if the reaping lift lever is lowered, the comparator is activated immediately and the reaping section is moved from the set position of the above ground height detection sensor. , a combine harvester that can be lowered to a preset lowering position, so that the reaping section can always be kept at the appropriate cutting height, and the reaping section can be carried out smoothly and efficiently. The object of the present invention is to provide a device for regulating the descent of a reaping section.

To explain the structure of the present invention with reference to the embodiment shown in the drawings, in FIGS. 1 to 5, 1 is a reaping section, and 2 is a threshing section. It can be raised and lowered freely by a hydraulic cylinder 3. Reference numeral 4 denotes a reaping lifting lever. The lifting lever 4 is provided at an operating position and operates the hydraulic cylinder 3 via an electromagnetic hydraulic switching valve 5. 6 is a tiller, and 6' is a grain culm promoter.
Reference numeral 7 denotes a vertical position detector (potentiometer) for the reaping section 1;
It is attached near the rotation fulcrum. 8 is the reaping part 1
The lowering position setting device 8 (variable resistor) is provided at the operating position and is manually adjusted.

A hydraulic cylinder 3 for raising and lowering the reaping section 1 is connected to a hydraulic pump 9 via an electrohydraulic switching valve 5, and the electrohydraulic switching valve 5 is connected to the lifting lever 4.
A rise provided at a position corresponding to the rising (B) and descending (A) positions of
By opening and closing the lower opening/closing switches 11 and 10, the lowering side or lowering side is switched. In addition,
The lift lever 4 is always held at a neutral position N by return springs 4a, 4a.
5' is a pilot check valve, 12 is an oil tank, and 13 is a relief valve. A ground height detection sensor 14 is provided at the lower part of the frame of the reaping section 1 to detect the appropriate position of the reaping section 1 relative to the ground. As shown in FIG. 4, this ground height detection sensor 14 has an upper limit opening/closing switch 15 that closes and turns ON when the reaping section is at a higher position than the proper position, and an upper limit switch 15 that is turned ON when the reaping section is at a lower position than the proper position. Close and turn on
A lower limit switch 16 is provided.

In the control circuit diagram of FIG. 5, reference numeral 17 is a comparator, and one input side of the comparator 17 is connected to the lowering position setter 8, and the lifting position detector 7 is the differential amplifier 18
The output side of the differential amplifier 18 is connected to the other input side of the comparator 17.
Tr1 and Tr2 are transistors, 19 is a changeover switch, and 20 is an indicator lamp. In addition, transistors Tr3 and Tr4 each have an electrohydraulic switching valve 5.
Electromagnetic solenoids 22, 2 on the rising side and the falling side of
1. A relay 23 opens a normally closed contact 23a when excited. 24
is attached near the pivot point of the reaping section 1, and the reaping section 1
This is a normally closed switch that opens when the reaping section 1 is raised above a predetermined raised position (a position where the reaping section 1 is raised for turning the aircraft). Then, set the changeover switch 19 to a.
A circuit in which the comparator 17 is connected to the transistor Tr3 by switching between the contact side and the B contact side;
Opening/closing switch 15 of the height above ground detection sensor 14,
16 can be switched to the circuits connected to the transistors Tr3 and Tr4, respectively.

In the device configured as described above, when the changeover switch 19 is switched to the A contact side to set the control mode, and the elevator lever 4 is operated to the lowering side A, the lowering side opening/closing switch 10 is closed, the transistor Tr3 is activated, and the electromagnetic The solenoid 21 is energized, the electrohydraulic switching valve 5 is switched to the reaping section lowering side, and the reaping section 1 is lowered. The lowering position of the reaping section 1 is detected by the lifting position detector 7, and the electrical signal from the differential amplifier 18 is input to the comparator 17, so that when the lowering position is set in advance by the lowering position setting device 8, The output of comparator 17 becomes high level and the transistor
Tr2 is activated, and the base potential of the transistor Tr3 is lowered and turned off, so that the reaping section 1 stops lowering at the position set by the lowering position setter 8. Therefore, even if the changeover switch 19 is switched to the a contact side and the control mode is set, the comparator 17 will not operate, and the comparator 17 will operate only when the lifting lever 4 is operated downward, and the reaping section 1 will be lowered. It is designed to descend to the set position. In this case, the transistor
Since Tr1 is also turned on at the same time, the indicator lamp 20 lights up to inform the driver that the reaping section 1 has reached the set position. Furthermore, when the elevator lever 4 is operated to the ascending side B, the opening/closing switch 11 on the ascending side is closed, the transistor Tr4 is turned on, the electromagnetic solenoid 22 is energized, the electrohydraulic switching valve 5 is switched to the ascending side, and the reaping section 1 is raised. do.

Furthermore, if the changeover switch 19 is switched to the B contact side, the transistors Tr3 and Tr4 will be connected to the open/close switches 15 and 16 of the height detection sensor 14, respectively, and the reaping section 1 will follow the irregularities on the field. The cutting height is maintained at an appropriate cutting height. That is, at the start of reaping, if the lift lever 4 is operated to the lowering side A of the reaping section 1, the on/off switch 10 is closed, and since the upper limit on/off switch 15 of the ground height detection sensor 14 and the normally closed contact 23a are closed, the transistor Tr is closed.
3 is turned on, and the reaping section 1 descends. When the reaping section 1 is lowered to the appropriate position of the ground height detection sensor 14, the upper limit switch 15 is opened and the transistor Tr3 is turned OFF, so that the reaping section 1 remains in its position regardless of whether the lifting lever 4 is operated on the lowering side. Stop at a position.

During work, when the reaping section 1 is higher than the ground, the upper limit switch 15 closes and lowers the reaping section 1, and conversely, when the reaping section 1 gets too close to the ground, the lower limit switch 16 closes and lowers the reaping section 1. 1
to rise. Therefore, the reaping unit 1 performs reaping work while being maintained at an appropriate reaping height that follows the unevenness of the field. When the reaping section 1 is raised when the machine is turning, etc., when the lift lever 4 is operated to the rise side B, the on/off switch 11 is closed and the transistor Tr is opened.
4 is turned ON, and the reaping section 1 rises.

In this case, the circuit on the lowering side of the reaping section 1 is connected to the relay 23.
Since the normally closed contact 23a is open, even if the upper limit switch 15 is closed, the lower electromagnetic solenoid 21
is not excited, and when the reaping section 1 is raised to the predetermined raised position, the normally closed switch 24 is opened, so even if the lifting lever 4 is returned to the neutral position, the reaping section 1 does not descend and remains at that position. Stop at.

As is clear from the above explanation, selector switch 1
If 9 is switched to the a contact side, the lowering of the reaping part 1 can be regulated to the set position by the lifting position detector 7 and the lowering position setter 8, and if it is switched to the b contact side, the height above the ground can be detected. Reaping section 1 by sensor 14
can be maintained in an appropriate position above the ground. Therefore, when it is inappropriate to control the elevation of the reaping section 1 by the ground height detection sensor 14, such as when mowing along the ridge, the elevation position detector 7 and the descending position setter 8 are used to restrict the descending. At the start of reaping work, etc., the lowering of the reaping section 1 can be regulated by the ground height detection sensor 14. Even if the changeover switch 19 is switched to the a contact side, unless the elevator lever 4 is operated downward, the reaping section 1 will not be lowered, and the elevator lever 4 will not be lowered.
Since the mowing section 1 is lowered to the preset position set in the lowering position setter 8 only when the lowering operation is performed, the reaping section 1 can be maintained at an appropriate cutting height without unnecessary operations.

In summary, the present invention includes a reaping section elevation position detector, a reaping section descending position setting device, a comparator that compares the detection value of the elevation position detector and the set value of the descending position setting device, and a reaping section. The control circuit for the hydraulic mechanism includes a circuit that uses a comparator to lower the reaping section to the lowering set position, and a hydraulic mechanism that raises and lowers the reaping section. A circuit for lowering the reaping section to the set position of the height detection sensor above the ground is provided, and a switch is provided to switch to either of the above two circuits, and when the switch is switched to the comparator side, Since the reaping section is configured to be lowered to the lowering setting position only when the reaping lift lever is operated downward, the lowering of the reaping section can be regulated by the ground height detection sensor at the start of reaping work, etc. Although the reaping section can be adjusted up and down to follow the unevenness of the field, when mowing along the ridge, etc., the changeover switch is switched to the comparator side, and the detected value of the elevation position of the reaping section and its lowering position are displayed. Even if a control system is set in which the lowering of the reaping section can be regulated by the set value, the set position of the height above ground detection sensor will not lower and remain fixed at the same position unless the reaping lift lever is operated downward. Moreover, when the reaping lift lever is lowered, the comparator is activated immediately and the reaping section can be lowered from the position set by the above-mentioned ground height detection sensor to the preset lowering position, making it easy to operate. There is no waste, so the reaping section can be maintained at an appropriate cutting height corresponding to field conditions, and the reaping work can be carried out smoothly and efficiently.

[Brief explanation of the drawing]

The drawings show an embodiment of the descending control device for the reaping section of a combine harvester according to the present invention, in which Fig. 1 is an overall side view of the combine, Fig. 2 is a hydraulic circuit diagram, and Fig. 3 shows the operation of the lifting lever. An explanatory diagram, FIG. 4 is a detailed diagram of the height above ground detection sensor, and FIG. 5 is a control circuit diagram. In the figure, 1 is a reaping section, 3 is a hydraulic cylinder, 4 is a lift lever, 5 is an electrohydraulic switching valve, 7 is a lift position detector, 8 is a lowering position setter, 14 is a ground height detection sensor, 15, 16 17 is a comparator, 18 is a differential amplifier, 19 is a selector switch, 20 is an indicator lamp, and 21 and 22 are electromagnetic solenoids of the electrohydraulic switching valve 5.

Claims (1)

[Scope of utility model registration request] A reaping section elevation position detector, a reaping section descending position setting device, a comparator for comparing the detected value of the elevation position detector and a set value of the descending position setting device, and a comparator for detecting the appropriate position of the reaping section relative to the ground. It is equipped with a height above the ground detection sensor and a hydraulic mechanism that raises and lowers the reaping section.The control circuit of the hydraulic mechanism includes a circuit that uses a comparator to lower the reaping section to the lowering setting position, and a circuit that uses a comparator to lower the reaping section to the set position, and a height above the ground detection sensor that raises and lowers the reaping section. A circuit for lowering the height above ground detection sensor to the set position is provided, and a switch is provided to switch to either of the above two circuits, and when the switch is switched to the comparator side,
1. A lowering regulating device for a reaping section in a combine harvester, characterized in that the reaping section is lowered to a lowering setting position only when a reaping lift lever is operated to lower the reaping section.