JPS5939215A - Apparatus for adjusting reaming height of combine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of a cutting height adjustment device for a combine harvester, and particularly proposes a cutting height adjustment device that improves the stability of automatic cutting height adjustment control.

The cutting height adjustment device of the combine switches the oil path through the operation of a delta electromagnetic directional control valve equipped with a solenoid that is energized and controlled by a manual switch, chi, and an automatic switch that opens and closes depending on the distance between the cutting part and the ground surface. The mowing height of the culm in the field is adjusted by operating a hydraulic cylinder to raise and lower the mowing section. By the way, with conventional cutting height adjustment devices, the reaping section is raised and lowered continuously in both manual adjustment performed by operating a manual switch and automatic adjustment performed by operating an automatic switch! The lifting speed is the same, and this speed is adjusted to a speed suitable for manual adjustment that requires relatively quick lifting and lowering, such as when raising and lowering the cutting part at the beginning of mowing, etc. has been done. However, this speed is too fast for automatic adjustment and tends to result in control notching, which impairs control stability.

In addition, when looking at the ground surface conditions, there are many irregularities, and the distance between the cutting part and the ground surface changes frequently and rapidly.As a result, automatic switches are opened and closed frequently, and hydraulic cylinders are operated frequently. In addition, the speed increases rapidly, leading to overcontrol and hunting, which also impairs the stability of control.

The present invention has been made in view of the above circumstances, and is capable of raising and lowering the reaping section at a lower speed in automatic adjustment than in manual adjustment by intermittent driving of a solenoid, and also provides an automatic switch. To provide a cutting height adjustment device which aims at the stability of cutting height adjustment control by driving a solenoid a little later than when the operating state becomes a state where a cutting part should be raised and lowered. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to drawings showing embodiments thereof.

FIG. 1 shows a combine harvester equipped with a cutting height adjustment device according to the present invention, in which a mounting rod of a grass divider plate 2 constituting a reaping part l is provided with a distance between the grass divider plate 2 and the ground surface. A sensor arm 3 is pivotally attached to the sensor arm 3, which rotates to move downward and upward in response to the movement. The reaping section 1, threshing section 9, driver's seat 10, etc. move up and down integrally around the rear part of the main frame as a rotation center by the vertical movement of the piston rod 4a of the hydraulic cylinder 4 attached to the front part of the main frame. Rotate and reap part 1
is designed to rise and fall. As shown in FIG. 2, the hydraulic circuit consisting of the hydraulic cylinder 4, a three-bottom, three-position switching type electromagnetic directional control valve 5, a hydraulic pump 6, etc. is activated by energizing the solenoid 5u of the electromagnetic directional control valve 5. The directional control valve 5 is in the switching position U, the hydraulic pressure in the hydraulic cylinder 4 rises to raise the reaping part 1, and when the solenoid 5d is energized, the magnetic directional control valve 5 is in the switching position d, and the hydraulic cylinder 4 is raised.
When the hydraulic pressure inside the cylinder decreases, the reaping unit 1 is lowered by its own weight, and the power to both solenoids, 5u and 5d is cut off, the electromagnetic directional control valve 5 is in the neutral position n, and the hydraulic cylinder 4 is The oil pressure is maintained at the time when the electromagnetic directional control valve 5 returns to the neutral position n, and the reaping section 1 stops moving up or down at that time.

The electric circuit in FIG. 2 shows a circuit for controlling the supply of electricity to the solenoids 5u and 5d. Combine key switch 121 manual automatic changeover switch 13
．． Both are single pole double throw type manual switch 14 and automatic switch 15. and switching members 16A and 16B. The reaping up/down lever 7 is arranged at the rear left of the driver's cab 8.

The 'r-shaped switching operation groove 70 shown together with the head of the reaping up/down lever 7 in FIG. It is shown in a plan view, and switching between manual and automatic mode can be performed by operating the reaping up/down lever 7 in the horizontal direction of the machine (vertical direction in Figure 2), and by operating it in the longitudinal direction of the machine (in the vertical direction in Figure 2). Manual lowering and raising can be switched by operating the lever in the right or left direction. That is, by locking the reaping up/down lever 7 in the groove 70a on the right side of the machine body (lower side in the figure), the manual automatic changeover switch 13 is turned on, and the left side (upper side in the figure) and front (right side in the figure) of the machine body is turned on. By engaging with the groove 70d of the machine, the manual switch 14 is connected to the switching terminal 14d, and by engaging with the groove 70u on the rear left side of the body, the manual switch 14 is connected to the switching terminal 14u. It has become. On the other hand, the automatic switch 15 is interlocked with the sensor arm 3, and when the sensor arm 3 is lowered by a predetermined amount or more, the automatic switch 15 is connected to the switching terminal 15d, and the sensor arm is raised by a predetermined amount or more. In this case, the automatic switch 15 is connected to the switching terminal 15u. And these connections are as follows. A common terminal 14c of the manual switch 14 is connected to the battery 11 via the switching member 16B and the key switch 12.
4 switching side terminals 14u and 14d are respectively solenoid 5u,
5d. On the other hand, one end of the intermittent switching member 16A is connected to the patch l via the key switch 12.
j ], connected to 1 and intermittent switching member 16A
The other end is connected to the common terminal 15c of the automatic switch 15 via the manual automatic changeover switch 13. Switching side terminals 15u and 15d of the automatic switch 15 are connected to one ends of the solenoids 5u and 5d, respectively.
The other end is body grounded.

As the intermittent switching members 16A and 16B, those that repeat opening and closing at predetermined time intervals, such as a flicker relay, a timer relay, or a combination of a pulse generation circuit and a switching circuit that is turned on and off by the pulse generation circuit, are used. What is important in the device of the present invention is that the intermittent switching member 16A connected to the automatic switch 15 is activated at the point when power is started to be applied to it (specifically, as shown in FIG. 3).
In a normal work situation where the key switch 12 is closed, the sensor arm 3 may rise more than a predetermined amount due to uneven ground surface from the state where the reaping part is at the appropriate height and the automatic switch 15 is open. Lower and connect terminal 15u or 15d
The method is to use a circuit that becomes closed a little later than when the circuit changes to the connected state. In other words, with flicker relays, the circuit remains open for a predetermined period of time immediately after the start of power application, and then closes, opens, closes, etc., and with timer relays, a time limit for opening and closing can be set, and after the timing starts, For devices that start operating from an open circuit cycle, and for combination circuits using the aforementioned pulse generation circuit, one pulse is emitted after a predetermined time delay from the start of energization, and this pulse activates the switching circuit. As shown in FIG. 3 (A), Q3), the closing time tA of the intermittent switching member 16A is the same as that of the intermittent switching member. 16B is adjusted so as to be shorter than the closing time tB of the switching member 16B.As a result, the intermittent switching member 16A operates.
The speed is lower than the lifting speed of the reaping section during manual adjustment when 6B is activated.

The device of the present invention configured as described above has a key switch 12.
When omitted, it operates, and the operation groove 70 switches the reaping upper and lower levers 7.
By engaging the groove 70a on the right side of the manual automatic changeover switch 13, the manual automatic changeover switch 13 is closed.

The sensor arm 3 descends or ascends depending on the distance between the grass dividing board 2 and the ground surface, so when the amount of descent or elevation exceeds a predetermined amount, the sensor arm 3 connects the common terminal 15c of the automatic switch 15 to the switching side. Terminal 15d or 15u is connected.

As a result, energization to the intermittent switching member 16A is started, and after a predetermined time delay, it closes and energization to the solenoid 5d or 5u is started.1 After that, the intermittent switching member 16A repeats opening and closing, so the solenoid 5d Alternatively, in 5u, the tracing of time tA is performed intermittently at ν periods. Therefore, the electromagnetic directional control valve 5 is repeatedly switched between the switching position d or U and the neutral position n in response to interruptions in energization.
The oil pressure in the hydraulic cylinder 4 is gradually lowered or raised, and as a result, the reaping section 1 is also lowered or raised gradually. Therefore, hunting will not occur due to excessive descending or ascending, and control stability will be improved.
In addition, in the case where the driver's seat 1° moves up and down together with the reaping section 1 to adjust the cutting height as in the above-mentioned embodiment, the operator's seat 1o, which is integrally linked up and down with the reaping section 1, can be raised and lowered. As a result, the riding comfort of combine harvesters equipped with the device of the present invention is improved, and users no longer experience unpleasant shocks.

On the other hand, if the sensor arm 3 returns to the proper position after the start of energization to the intermittent switching member 16A until it first closes the circuit, that is, if the distance between the grass dividing plate 2 and the ground surface is When the value falls within a range that does not require adjustment, the self+lJI+ switch 15 opens, so the solenoid 5
d or 5u is not energized, and the reaping section 1 is not raised or lowered. That is, when the automatic switch 15 is repeatedly opened and closed in short cycles due to unevenness of the ground surface, the mowing section is not raised or lowered unnecessarily. This prevents hunting due to overcontrol.

Next, the reaping up/down lever 7 is engaged with the front groove 70d or the rear groove 70 II on the left side of the switching operation groove 7o, thereby connecting the common terminal 14c of the manual switch 14 and the switching side terminal 1.
4d or 14u is connected, and solenoid 5d or 5u is energized. This causes the electromagnetic directional control valve 5 to switch to the switching position d.
or U, so the oil pressure in the hydraulic cylinder 4 falls or rises, and the reaping section 1 falls or rises. That is, the cutting height is manually adjusted by such an operation, and since the intermittent switching member 16B operates, the solenoid 5d
Alternatively, the energization to 5u is performed intermittently depending on the closing time tB of the switching member 16B. Because of this structure, the lifting speed of the reaping section is faster than when automatic adjustment is used, which enables emergency adjustment of the cutting height, which is the purpose of manual adjustment, while also preventing excessive lifting and lowering during reaping work, and also prevents abnormalities in the conveyance system. It doesn't give birth.

As described in detail above, the present invention allows the reaping section to be raised and lowered intermittently to adjust the cutting height, and the reaping section is raised and lowered after a predetermined period of time elapses after the automatic switch operates to raise and lower the reaping section. This increases the stability of automatic cutting height adjustment. On the other hand, manual adjustment allows the elevator to move up and down at a higher speed than automatic adjustment, so there is no problem with emergency adjustment. Of course, manual adjustment may be performed continuously.

As described above, the present invention has a significant effect on improving the stability of the automatic cutting height adjustment control of a combine harvester.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a perspective view of a combine equipped with the device of the present invention, FIG. 2 is an electric circuit diagram shown together with a hydraulic circuit diagram of the device of the present invention, and FIG. 5
) and (B) are time charts showing the opening and closing times of the intermittent switching members 16A and 16B, respectively. 1... Reaping part 2... Grass dividing board 3... Sensor arm 4... Hydraulic cylinder 5 River electromagnetic directional control valve 5 u
, Solenoid for 5 d 7 River reaping up and down lever 13...
・Manual automatic changeover switch 14...Manual switch 1
5...Automatic switch 16A, 16B...Intermittent switching member patent applicant Noboru Kono, patent attorney for Yanmar Agricultural Machinery Co., Ltd.

Claims (1)

[Claims] 1. Operation of an electromagnetic directional control valve equipped with a solenoid whose energization is controlled on and off by an automatic switch that opens and closes in accordance with the distance between the reaping part and the ground surface. In the cutting height adjustment device for a combine harvester, which operates a hydraulic cylinder to raise and lower the reaping part, the automatic switch operates to raise and lower the reaping part during the control circuit for controlling energization to the solenoid by the automatic switch. After a predetermined time interval from the point in time,
A cutting height adjusting device characterized by being provided with an intermittent switching member that intermittently energizes a solenoid at predetermined time intervals.