JPH0528086B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a combine harvester in which a reaping section is connected to the front part of a traveling vehicle body equipped with a threshing device so that it can be raised and lowered. The present invention relates to a technique for raising and lowering a reaping section while following the ground.

[Conventional technology]

Conventionally, as the technology mentioned above, for example,
As shown in Publication No. 109726, a ground-contact type sensor is provided on the lower surface of the reaping section, and the sensor is mechanically linked with a hydraulic valve of a hydraulic cylinder that raises and lowers the reaping section, thereby creating a reaping section with a ground-contacting sensor. In some models, a sensor and a hydraulic valve are configured in a feedback operation linkage structure so that the posture of the plant can be maintained constant. Some have electrical control structures that operate hydraulic valves to maintain the temperature at a constant level (reference not listed).

[Problem that the invention seeks to solve]

However, as mentioned above, if you try to configure a control system to automatically raise and lower the reaping section, the structure will become complicated, such as having to provide a sensor or a linkage structure for control. There is room for improvement from a cost perspective.

An object of the present invention is to construct an elevating structure for the reaping section to follow the ground as simply as possible through rational modification.

[Means for solving problems]

The characteristic configuration of the present invention is that a hydraulic cylinder is provided for raising and lowering the reaping section, and an accumulator is provided in the oil path to the hydraulic cylinder, and the reaping is carried out by the contact with the ground of the ground-contacting body provided at the lower part of the reaping section. A ground-following structure for the reaping section is configured so that the section can be raised and lowered,
A pressure sensor is provided in the oil passage, and the pressure sensor detects that the oil pressure is lower than a first predetermined value that is set lower than the oil pressure of the oil passage when the ground contact pressure of the ground contacting body to the ground is appropriate. When it is detected that the pressure oil in the oil passage has decreased in pressure, supply of pressure oil to the hydraulic cylinder is started, and the pressure oil in the oil passage is increased in pressure to a second predetermined value, which is higher than the first predetermined value, by the pressure sensor. A pressure setting mechanism is provided which stops the supply of pressure oil to the hydraulic cylinder when it detects that the above-mentioned pressure oil has been removed, and is configured to set a level for the reaping section to follow the ground.The functions and effects thereof are as follows. It is as follows.

[Effect]

When the reaping section is lowered from the raised position at the start of work, the pressure in the oil passage of the hydraulic cylinder decreases when the lower grounding body descends until it makes relatively strong contact with the ground and supports part of the weight. When the pressure drops below the first set value, the supply of pressure oil to the hydraulic cylinder is started, the reaping section rises, and the pressure in the oil passage is reduced to a level at which the ground contact body does not completely float up.
When the pressure reaches the set pressure, the pressure oil supply is stopped at that point. Moreover, since an accumulator is connected to the oil passage, the reaping section is elastically supported within the above-mentioned set pressure range, and as a result, the reaping section always maintains a certain level of ground pressure without the hydraulic cylinder being driven. It follows the ground and moves up and down smoothly. If there are large irregularities on the reaping work surface, the internal pressure of the oil passage will be out of the set range, and the entire lifting and lowering operation will be performed by supplying and discharging pressure oil to the hydraulic cylinder. It is maintained within the set range, and smooth ground-following lifting and lowering operations can be maintained.

〔Effect of the invention〕

Therefore, it has become possible to provide a reaping section elevating mechanism with a relatively simple structure, which allows the level of the reaping section to be set relatively quickly and allows the reaping section to smoothly move up and down following the ground at a predetermined ground pressure.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in Fig. 3, a reaping section B is connected to the front part of a car body A that is equipped with a threshing device 1 and a grain tank 2 and runs on a pair of left and right crawler traveling devices 3, so that it can be raised and lowered, and all culms are fed. Configure type combine.

The reaping section B includes a reel 4 that scrapes the planted grain culm K, a clipper-type reaping device 5 that cuts the planted grain culm K, a conveyor 6 that sends the grain culm from the reaping device 5 to the rear, and the conveyor 6. an auger 7 that brings the grain culms from the auger to approximately the left and right center of the reaping section B; and a feeding device 8 that sends the grain culms from the auger 7 to the handling chamber 1a of the threshing device 1;
It consists of

The supply device 8 also includes front and rear wheels 8a, 8b and an endless band 8c wound around the front and rear wheels 8a, 8b.
The power from the running vehicle body A is transferred to the rear wheel body 8b.
At the same time, this power is transmitted to the support shaft 9 of the wheel body 8a via the front wheel body 8a, and the power transmitted to the support shaft 9 also drives the reel 4 and the conveyor 6. , the auger 7 is driven,
Further, a drive system (not shown) is configured so that the reaping device 5 is driven back and forth.

Also, the support shaft 10 of the rear wheel body 8b of the supply device 8
, both ends of which are freely rotatably supported by the traveling vehicle body A, and the reaping section B swings up and down around the support shaft 10 by the operation of a hydraulic cylinder 11 disposed between the traveling vehicle body A and the reaping device 5. is configured to do so.

In this combine harvester, the reaping section B is made to follow the ground G by slidingly contacting the reaping section B with the ground G.
The structure is such that it can be raised and lowered.

That is, a sliding body 12 (an example of a grounding body) made of a sled-like member is provided on the lower surface of the reaping part B, and a first
As shown in the figure, an accumulator 14 is provided in the oil passage 13 to the hydraulic cylinder 11, so that during harvesting, the reaping section B can be set to a predetermined level in advance, and the elastic supporting action of the accumulator 14 will allow the harvest to be harvested. The part B moves up and down while following the ground G.

Further, in order to set the reaping part B to a predetermined level before starting work, a pressure sensor 15 is provided to detect the pressure in the oil passage 13, and the pressure sensor 15
A signal from the Schmitt circuit 16 is inputted to the automatic control on/off operation switch 17.
A control device 18 is provided, into which a signal from the
Furthermore, a signal path is formed so that a solenoid valve 19 for driving and controlling the hydraulic cylinder 11 is operated by a signal from the control device 18. When starting the reaping work, when the operation switch 17 is turned on, a descending signal is issued from the control device 18 to the solenoid valve 19, and the sliding body 12 formed on the lower surface of the reaping part B is brought into contact with the ground G. lower until it makes relatively strong contact. That is, as the reaping section B descends to the ground, the internal pressure in the oil passage 13 changes, and as shown in FIG. 2, the output signal of the Schmitt circuit 16 that converts the signal from the pressure sensor is switched to (OFF). The reaping section B up to this point is lowered.

Then, when the detected pressure of the pressure sensor falls to the first set pressure P ₁ shown in FIG. The signal is emitted, and the reaping section B is raised. Then, as the reaping part B is raised, the internal pressure of the oil passage 13 increases to a second predetermined pressure _P2.
When the cutting section B is raised to this point, the raising operation of the reaping section B is stopped when the Schmitt circuit 16 is turned ON again. The level of the reaping section B is set so that the sliding body 12 lightly contacts the ground G in this stopped state. To be more specific, the pressure P ₀ in the graph shown in Fig. 2 is the value when the reaping part B is completely supported by the ground G,
P ₁ is the value when the sliding body 12 is in relatively strong contact with the ground G, pressure P ₂ is the value when the sliding body 12 is in light contact with the ground, and pressure P ₃ is the value when the sliding body 12 is in light contact with the ground G. It is the value of the boundary where the body 12 is separated from the ground G,
Further, the pressure region formed between the pressures P ₁ and P ₂ is made to coincide with the hysteresis region formed in the Schmitt circuit 16.

In this way, at the start of work, simply by turning on the operating switch 17, the reaping section B descends at a relatively high speed, then rises slightly at a slow speed, and is maintained at a predetermined level.

Moreover, since the reaping part B is raised and lowered by contact with the ground G in this way, the hydraulic pump 20 that supplies pressure oil to the solenoid valve 19 is only driven when the solenoid valve 19 is operated. , the hydraulic pump 2
The electric motor 21 that drives the
A system is provided for controlling the operation of the electric motor 21 so that a control signal is supplied to the electromagnetic valve 19 only when the control signal is issued from the electromagnetic valve 19.

The Schmidt circuit 16 and the control device 18 are referred to as a pressure setting mechanism C, and as shown in FIG. An input signal system is also formed to input the signal.

[Another example]

In addition to the embodiments described above, the present invention includes, for example, a control device configured with a microprocessor, and a program configured to set the level of the reaping section as described above based on a signal from a pressure sensor. It is also possible to omit the
Alternatively, the pressure sensor may be constructed by incorporating a diaphragm or the like and using a pressure sensor that generates hysteresis due to its mechanical structure.

[Brief explanation of drawings]

The drawings show an embodiment of the combine harvester according to the present invention, FIG. 1 is a block diagram showing the lifting control system of the reaping section, FIG. 2 is a graph showing pressure changes in the oil passage with respect to the hydraulic cylinder, and FIG. It is a partially cutaway side view showing the structure of the front part. 1... Threshing device, 11... Hydraulic cylinder, 12
... Grounding body, 13 ... Oil path, 14 ... Accumulator, 15 ... Pressure sensor, A ... Traveling vehicle body, B
... Reaping section, C ... Pressure setting mechanism, P ₁ ... First
Set pressure, P ₂ ...Second set pressure.

Claims (1)

[Claims] 1 A combine harvester in which a reaping part B is connected to the front part of a traveling vehicle body A equipped with a threshing device 1 so as to be able to rise and lower, and a hydraulic cylinder 11 for raising and lowering the reaping part B is provided, and the hydraulic cylinder Oil road 1 to 11
3 is provided with an accumulator 14, and the reaping section B
A ground following structure of the reaping part B is configured so that the reaping part B is raised and lowered by contact with the ground of the grounding body 12 provided at the lower part of the reaping part B, and a pressure sensor 15 is installed in the oil passage 13.
and the pressure sensor 15 indicates that the oil passage is below a first predetermined value _P1 , which is set lower than the oil pressure of the oil passage 13 when the ground contact pressure of the grounding body 12 to the ground is appropriate. 13, the pressure oil supply to the hydraulic cylinder 11 is started, and the pressure sensor 15 detects that the oil passage has reached a second predetermined value _P2 higher than the first predetermined value _P1 . 13
a pressure setting mechanism C that stops supplying pressure oil to the hydraulic cylinder 11 when detecting an increase in the pressure of the pressure oil;
A combine harvester configured to set a level for ground following of the reaping part B.