JPH0430245B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a combine harvester equipped with an automatic cutting height control device that automatically drives the cutting section up and down.

[Conventional technology]

Some combine harvesters are equipped with an automatic cutting height control device that automatically drives the cutting section up and down so that the height from the ground to the cutting section is maintained within a set range, as described above. This automatic cutting height control device includes a sensor that detects the height from the ground to the cutting section, a hydraulic actuator that drives the cutting section up and down, a control valve that supplies and discharges hydraulic oil to this hydraulic actuator, and this control valve. It consists of an operating device that operates the controller, and a control circuit that issues operating signals to the operating device.

This combine harvester is equipped with a manually operated lift lever that can forcefully operate the control valve to the ascending side and descending side against the operation of the operating device. This allows the operator to forcefully raise and lower the reaping section by operating the control valve using the lift lever, regardless of whether the automatic cutting height control device is activated or stopped.

[Problem to be solved by the invention]

The automatic mowing height control system described above is equipped with a manually operated changeover switch for activation and deactivation. Therefore, for example, suppose that, with the changeover switch in the automatic position (operating state), the reaping section is raised significantly using the lift lever and the main switch (key switch) of the combine is turned off.

In this state, all functions such as the automatic cutting height control device stop and the reaping section stops in the raised position, but after this, with the changeover switch in the automatic position, the main switch is turned on and operated. shall be. In this case, unless the operator operates the lift lever, the automatic cutting height control device takes priority.
This automatic cutting height control device judged that the cutting section was too high above the set range and lowered the cutting section rapidly to near the ground, leaving room for improvement in terms of safety.

In particular, a single-acting hydraulic cylinder is generally used to raise and lower the reaping section of a combine, and the lowering is done by the weight of the reaping section, so even if the hydraulic pump is not operated by the engine, the above-mentioned Even if the main switch is turned on, the reaping section will only be lowered.

An object of the present invention is to prevent a situation where the reaping section unexpectedly descends when the main switch is turned on.

[Means to solve the problem]

The feature of the present invention is that the combine harvester equipped with the automatic cutting height control device and the lifting lever for forced lifting as described above is configured as follows. That is, it is equipped with a start switch that detects when the lift lever is operated to the lowered position, a presence/absence sensor that detects the presence or absence of grain culm in the grain culm passage of the reaping section, and a changeover switch that is manually operated. , when the changeover switch is in the automatic position and the activation switch is in the lifting lever detection state, or when the changeover switch is in the automatic position and the presence/absence sensor is in the grain culm detection state, The automatic cutting height control device is configured to start operating, and its functions and effects are as follows.

[Effect]

For example, suppose that the switch for the automatic cutting height control device is operated to the automatic position, the mowing section is raised significantly using the lift lever, and the main switch of the combine is turned off. It is assumed that the main switch is turned on from this state.

In this case, with the configuration described above, if the changeover switch is in the automatic position when the main switch is turned on, the automatic cutting height control device will not operate and the reaping unit will stop at that position. . Then, when the lift lever is operated from this stopped state to the lowered position, the automatic mowing height control device starts operating.

In this case, even if the automatic mowing height control device starts operating, the control valve is forcibly operated in the downward direction, giving priority to the operation of the lift lever. If the control valve is operated upward, the automatic cutting height control device also attempts to operate the control valve downward, so the control valve operation method is the same and no particular problem occurs. After this, if you return the lift lever to the neutral stop position or release your hand from the lift lever, the automatic mowing height control device will take priority, so from now on, the reaping unit will automatically move up and down. It will be done.

If you turn on the main switch while the selector switch is in the automatic position,
When the presence/absence sensor detects that the grain culm is present in the grain culm surface path in the reaping section, the automatic cutting height control device starts operating. In other words, in this state, the reaping operation has started and the harvested grain culms have been fed into the reaping section, so it is necessary to immediately start the automatic lifting and lowering of the reaping section.

〔Effect of the invention〕

As described above, instead of structuring the reaping section so that the automatic lifting and lowering of the reaping section is started simply by operating the changeover switch for the automatic cutting height control device to the automatic position, it is possible to The structure is configured so that the automatic raising and lowering of the reaping section will not start unless another operation is performed (operating the raising/lowering lever to the lowered position or starting the reaping operation).
It was possible to prevent the accidental lowering of the reaping section when the main switch was turned on, thereby improving the safety of the combine harvester.

Further, if the conditions are only for the lift lever and the changeover switch, even if the changeover switch is operated to the automatic position, automatic lifting of the reaping section will not start unless the lift lever is operated to the lowered position. Therefore, if you start reaping work without operating the lift lever to the lower position after operating the changeover switch to the automatic position,
Reaping may be performed without the reaping unit automatically moving up and down.

However, in the present invention, when the reaping operation is started with the changeover switch set to the automatic position, when the existence sensor detects that the reaped grain culm has entered the grain culm passage, the reaping operation is started. Since the automatic lifting and lowering of the parts starts, there is no problem like the one mentioned above.

〔Example〕

FIG. 3 shows the front part of a combine harvester in which a reaping part 3 that is raised and lowered by a single-acting hydraulic cylinder 2 (corresponding to a hydraulic actuator) is connected to the front part of a traveling vehicle body 1.

The hydraulic cylinder 2, as shown in FIG.
The solenoid mechanism 4 is connected to a neutral return type control valve 5 which is switched between three positions by a solenoid mechanism 4 (corresponding to an operating device) that operates in forward and reverse directions, and the solenoid mechanism 4 is connected to a control circuit 6 using a microcomputer. They are connected via drive circuits 7a and 7b for forward and reverse operation.

The reaping section 3 is equipped with an ultrasonic sensor 8 that detects the height of the reaping section 3 above the ground and includes a transmitter 8a and a receiver 8b. The detection signal from the sensor 8 and the setting signal from the manually adjustable cutting height setting device 9 are input to the control circuit 6, and the height of the cutting section 3 from the ground is maintained within the setting range. Thus, the control valve 5 is automatically operated by the control circuit 6 and the solenoid mechanism 4, and this is the automatic elevation control of the reaping section 3.

The control valve 5 is also mechanically linked to a neutral return type lifting lever 10 that is manually operated. Thereby, by operating the lift lever 10, the operator can operate the control valve 5 to the upward or downward side against the operation of the solenoid mechanism 4. A flexibility 12 (elongated hole and pin structure) is provided between the elevator lever 10 and the control valve 5 to allow the solenoid mechanism 4 to switch the control valve 5 when the elevator lever 10 is at the neutral stop position N. ing.

Further, a first switch detects that the elevating lever 10 is operated to the lower position D and the upper position U.
S ₁ (corresponding to a starting switch) and a second switch S ₂ are provided, and a contact type presence/absence sensor S ₀ for detecting the presence or absence of grain culms is provided in the grain culm passage of the reaping section 3. A third switch S3 is provided to sense that the reaping clutch lever 11, which operates a transmission clutch (not shown) to the reaping section ₃ , is in the clutch engaged position ON, and these switches _S1 , S ₂ , _S3 and sensor _S0 are connected to the control circuit 6 along with a changeover switch Sm for automatic cutting height control.
It is connected to the.

The present invention is constructed as described above, and its operation is shown in the flowchart of FIG.

When the changeover switch Sm is set to "auto", the presence/absence sensor _S0 indicates that there is a grain culm in the reaping section 3.
Immediately upon detection, automatic elevation control of the reaping section 3 is started.

When the changeover switch Sm is set to "auto", if the reaping clutch is engaged, this is detected by the third switch S3, and automatic elevation control of the reaping section ₃ is immediately started.

When the changeover switch Sm is set to "auto", when the elevator lever 10 is operated to the lower position D, the operation is detected by the first switch _S1 and automatic elevation control of the reaping section 3 is started.

In this case, the lift lever 1 is lower than the automatic lift control.
Since operation 0 has priority, lift lever 1
0 continues to be held at the lowered position D, the reaping section 3
goes down. Then, when you release your hand from the lift lever 10 or return the lift lever 10 to the neutral stop position N, the control valve 5 can be operated by the solenoid mechanism 4, so that the automatic lift control of the reaping section 3 can be performed thereafter. will be carried out.

When the lift lever 10 is operated to the raised position U,
This is detected by the second switch _S2 , and the automatic elevation control of the reaping section 3 is stopped.

[Brief explanation of drawings]

The drawings show an embodiment of a combine harvester with an automatic cutting height control device according to the present invention, and FIG. 1 is a flowchart of automatic cutting height control, FIG. 2 is a block diagram of the automatic cutting height control device, and FIG. 3 is a flowchart of the automatic cutting height control device. is a front side view of the combine. 2...Hydraulic actuator, 3...Reaping section, 4
... Control valve operating device, 5 ... Control valve, 8 ... Sensor that detects the height from the ground to the reaping section, 10
... Lifting lever, Sm ... Selector switch, S ₀ ...
Presence sensor, S ₁ ...Start switch.

Claims (1)

[Scope of Claims] 1. A sensor 8 that detects the height from the ground to the reaping section 3, a control valve 5 that supplies and discharges hydraulic oil to a hydraulic actuator 2 that drives the reaping section 3 up and down;
and an operating device 4 for operating the control valve 5,
An automatic mowing height control device is provided which raises and lowers the reaping section 3 by operating a control valve 5 using the operating device 4 so that the detected value of the sensor 8 is maintained within a set range, and also includes A combine harvester with an automatic mowing height control device, which is equipped with a manually operated lift lever 10 that can forcefully raise and lower the control valve 5 against the a start switch S ₁ that detects that it has been operated; and the reaping section 3
Presence sensor that detects the presence or absence of grain culms in the grain culm passage
_S0 and a changeover switch _Sn that is manually operated, and when the changeover switch _Sn is in the automatic position and the start switch _S1 is in the detection state of the lift lever 10, or the changeover switch
A combine with an automatic cutting height control device configured such that the automatic cutting height control device starts operating when S _n is in the automatic position and the presence/absence sensor S ₀ is in a grain culm detection state. .