JPH052976Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a work machine elevation control device for mobile agricultural machinery, particularly to a pretreatment section elevation control device for a combine harvester, and more specifically to a work machine elevation control device that allows setting of the lowering position of the work machine. .

We have already installed a detector to detect the lowering position of the work equipment (pre-processing section), and a comparator compares the output of the detector with the output from the setting device, and the pre-processing section is automatically lowered at the set position. A stopping device has been proposed. However, when setting or correcting the descending stop position using the setting device, this device cannot confirm the descending stop position unless the pre-processing section is raised once, the setting device is adjusted, and the descending stop position is lowered again. First, in order to set the descending stop position at a desired position in relation to the ground height or the nap, it was necessary to repeatedly move the processing section up and down to make adjustments, which was very troublesome.

Therefore, the present invention installs a circuit that can compare the outputs from the detector and setting device at the lowered position of the work equipment, regardless of the operation of the control lever, and the work equipment moves up and down in accordance with the adjustment of the setting device. It is an object of the present invention to provide a working machine lifting/lowering control device which is configured to be adjustable and which eliminates the above-mentioned drawbacks.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the pre-processing section 1 in the combine has a frame 6 that supports a divider 2, a moving device 3, a cutting blade 5, etc.
The frame 6 is supported above the machine frame 9 by a support shaft 7 via a connecting frame 6' so as to be swingable in the vertical direction, and is rotatably connected to a support rod 10 below.・Supported.
Further, the support rod 10 is composed of a bell crank that is pivotally supported on a support shaft 11 provided on the machine frame 9, and a hydraulic cylinder 12 is connected to the other end arm 10a of the support rod 10. cylinder 12
The pre-processing section 1 is driven up and down based on the expansion and contraction of. Further, as shown in FIG. 2, near the driver's seat of the combine harvester, a pre-processing section lifting/lowering operating lever 13 constituting the operating means is installed.
is capable of controlling on/off the ascending limit switch Su and the descending limit switch Sd, and
It is urged by springs 15, 15 to return to the central position. On the other hand, the connecting frame 6'
As shown in FIGS. 3 and 4, a pin 16 is welded to the upper pivot portion, and a bracket 1 is attached to the machine frame 9 adjacent to the frame 6'.
A potentiometer 19 is arranged via 7. Furthermore, the input shaft 19 of the potentiometer 19
An arm 20 having a slit 20a is fixed to a, and the pin 16 is received in the slit 20a of the arm. Therefore, the potentiometer 19 constitutes a detector that detects the vertical position of the preprocessing section 1 as a change in the amount of electricity. and,
As shown in FIG. 5, the hydraulic cylinder 12 communicates with an electromagnetic switching valve 22 via a pilot operated check valve 21, and the switching valve 22 further communicates with a pump 23 and a tank 25. In addition, in the figure, 22d
22u is a solenoid for discharging the hydraulic cylinder 12, that is, lowering the pretreatment section; 22u is a solenoid for supplying pressure oil to the hydraulic cylinder 12, that is, raising the pretreatment section; and 26 is a relief valve.

As shown in FIG. 6, a setting device 27 and a potentiometer 19 are connected to comparators 30 and 31 via an amplifier 29, and an inverter 32, AND circuits 33 and 35, and an OR circuit 36 and
37, and are connected to solenoids 22d and 22u for lowering and raising operations, respectively, via output stage transistors 38 and 38'. Also,
AND circuits 33 and 35 have two NAND circuits 3
Trigger pulse generation switches Sd and Su operated by the operating lever 13 are connected via a bistable circuit 39 consisting of 6 and 37, and these switches Sd and Su are further connected. Sd and Su are connected to OR circuits 36 and 37 via inverters 40 and 41. In addition,
The setting device 27 allows the operator to freely set the amount of electricity by turning a dial at the driver's seat, and the comparator 31 has a dead zone a.

Since the present embodiment has the above-described configuration, when the operating lever 13 is operated to turn on the lowering switch Sd for one pulse when the preprocessing section 1 is in the raised position, the output is sent to the OR circuit 36 via the inverter 40. While the H signal is input, the signal is input through the bistable circuit 39.
The H signal is input to AND circuits 33 and 35. As a result, the OR circuit 36 outputs H, energizes the lowering solenoid 22d via the transistor 38, operates the switching valve 22, and lowers the preprocessing section 1. Furthermore, even if the operating lever 13 is returned to the neutral position by the spring 15 and the switch Sd is turned off, the output e1 from the setting device 27 will be transferred from the potentiometer 19 to the amplifier 29 while the preprocessing section 1 is in the raised position. Since the output via e2 is smaller than (e1
<e2), the comparator 30 outputs an L signal, and further outputs an H signal to the AND circuit 33 via the inverter 32, and together with the H signal from the bistable circuit 39, the AND circuit 33 outputs H. do. This results in
Even after the H signal input to the OR circuit 36 is cut off by turning off the switch Sd, the OR circuit 36 continues to output an H signal and the preprocessing section 1 is lowered. At this time, the comparator 31 outputs an L signal based on (e1-a)<e2, but the AND circuit 35 does not output an L signal, and the solenoid 22u is not excited.

Then, when the preprocessing section 1 descends to the position preset by the setting device 27, the output e1 from the setting device 27 becomes larger than the output e2 from the potentiometer 19 (e1>e2), so the comparator 30 The AND circuit 33 outputs the H signal, and the AND circuit 33 receives the L signal and does not output the L signal, thereby canceling the excitation of the solenoid 22d and stopping the lowering of the preprocessing section 1. At this time, the comparator 31 is (e1-) due to the dead zone a.
a) It remains an L signal based on <e2,
The solenoid 22u is maintained without being excited to prevent hunting.

Furthermore, in order to raise the preprocessing section 1 when turning the combine, the operator operates the operating lever 13 and turns on the switch Su. Then, an H signal is input to the OR circuit 37 via the inverter 41, and
The bistable circuit 39 is switched and the AND circuit 33,
The L signal is input to 35. As a result, the OR circuit 37 outputs H, energizes the lifting solenoid 22u via the transistor 38', and the switching valve 22
Operate to raise the pretreatment section. Note that this rising operation is maintained while the operating lever 12 turns on the switch Su, and stops when the operating lever 12 returns to the neutral position and the switch Su is turned off.

To adjust the lowering position of the pre-processing section 1, set the setting device 2 with the pre-processing section 1 in the lowered position.
7 using a dial, etc. For example, if the setter 27 is adjusted to lower the lowering position of the preprocessing section 1, the output e1 from the setter 27 will be lowered,
Based on e1<e2, the comparator 30 outputs an L signal, and therefore, an H signal is input to the AND circuit 33 via the inverter 32. In this state, since the preprocessing section 1 is in the lowered position, the H signal is input from the bistable circuit 39 to the AND circuit 33, so the H signal is input to the OR circuit 36.
Therefore, the lowering solenoid 22d is energized, and the pre-processing section 1 follows the adjustment of the setting device 27 so that e1>e2
descend until In addition, in order to set the setting device 27 so that the lowering position of the pre-processing section 1 is high,
The output e1 from the setting device 27 is the dead band a of the comparator 31
Adjust to exceed. Then, (e1-a)>e2
Based on this, the comparator 31 outputs an H signal, and together with the fact that the H signal is input from the bistable circuit 39 to the AND circuit 35, the AND circuit 35 outputs an H signal.
Then, by exciting the ascending solenoid 22u via the OR circuit 37 and the transistor 38', the pre-processing section 1 follows the adjustment of the setting device 27 so that (e1-a)<
It increases until it reaches e2.

As explained above, according to the present invention, the height of the work machine 1 relative to the machine frame 9 can always be detected by the detector 19, and the work lowering position can be arbitrarily set by the setting device 27. It is possible to prevent the working machine 1 from thrusting into the field at the start of the reaping work after turning is completed, and also to reliably prevent malfunctions due to erroneous detection of waste straw, stubble, etc.
It is possible to perform stable work at all times, and the height above the ground can be adjusted over a sufficient range. Furthermore, simply by operating the operating means 13 in the lowering direction, the work implement 1 is automatically lowered to the set position.
Not only is it extremely easy to operate, but the work equipment 1
By simply adjusting the setting device 27 at the lowered position, the work equipment 1 can be raised or lowered in accordance with the setting value of the setting device 27, and the operator can easily adjust the height above the ground or the relationship with the workpiece. Moreover, the lowering position of the working machine 1 can be adjusted quickly. Furthermore, since the detector 19 is arranged on the same side of the machine frame 9 as the operating means 13 and the setting device 27, the detector 19,
Coupled with the fact that the setting device 27 and the operating means 13 are connected electrically, the connection structure can be made simple and reliable, and the cutting height can be reduced without requiring delicate moving parts and many limit switches. Coupled with the fact that the sensor can be omitted, the structure can be significantly simplified and costs can be reduced, and maintenance etc. can be facilitated. Then, the descending signal Sd and the ascending signal Su of the operating means 13 are
, the control means 39 is switched and held at the lowering operation position and the raising operation position, and based on the lowering operation of the operating means 13 at the predetermined position of the control means 39, the work implement 1 is lowered to the lowering position set by the setting device 27. The work equipment 1 is lowered to the position, and the work equipment 1 is raised during that time by continuous raising operation of the operating means 13, and the work equipment is adjusted up and down by operating the setting device 27 at the lowering operation position. This makes it possible to control all the elevations of the working machine 1, improving operability and preventing problems caused by erroneous operations.

[Brief explanation of the drawing]

Fig. 1 is a schematic side view showing the preprocessing section of a combine to which the present invention can be applied, Fig. 2 is a side view showing the operating lever, Fig. 3 is a side view showing the detector, and Fig. 4 is a plan view thereof. , FIG. 5 is a hydraulic circuit diagram, and FIG. 6 is an electric circuit diagram according to the present invention. DESCRIPTION OF SYMBOLS 1... Work equipment (pretreatment part), 9... Machine frame, 12... Hydraulic cylinder, 13... Operation means (lever), Su, Sd... Lifting switch, 19...
...Detector (potentiometer), 22...Solenoid switching valve, 22u, 22d...Solenoid, 27...
Setting device, 30, 31... Comparator, 39... Control means (bistable circuit).

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A mobile agricultural machine in which a working machine is supported on the machine frame so as to be able to rise and fall freely, and the working machine is driven up and down by a hydraulic cylinder controlled based on an electromagnetic switching valve. an operating means for emitting a rising signal; a detector for detecting the lowering position of the working equipment with respect to the main machine frame as a change in the quantity of electricity; a setting device for presetting the lowering position of the working equipment as a predetermined quantity of electricity; a control means that is switched by a descending signal and an ascending signal of the means, and switches and holds the control means in a descending operating position and a rising operating position, and switches and maintains the controlling means in the descending operating position based on the descending signal from the operating means. Then, compare the amount of electricity from the detector and the setting device,
The electromagnetic switching valve is configured to be controlled in the downward direction until it reaches the downward position set by the setting device, and the control means is switched and held at the upward operating position based on the upward signal from the operating means. , the electromagnetic switching valve is controlled to the upward side while the upward signal of the operating means is being outputted, and based on the adjustment of the setting device while the control means is held at the downward operating position. ,
A working machine elevation control device configured to adjust the elevation of the working machine in accordance with adjustment of the setting device so that the electrical quantity of the detector matches the electrical quantity of the setting device. (2) The working machine elevation control device according to claim 1, wherein the control means is a bistable circuit.