JPS6237929B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a handling depth adjustment device for a combine harvester.

The handling depth adjustment device of the combine shown in Fig. 1 is used to adjust the handling depth of the harvested grains, which are clamped in the vertical conveyance chain 1, before the harvested grain culms are transferred to the feed chain 2 and fed to the handling cylinder. An electromagnetic directional control valve is provided which is equipped with a solenoid that detects the length of the grain culm using two automatic switches M and H, such as a limit switch, arranged in front, and controls the energization on and off according to the detection result. The electromagnetic directional control valve changes the oil path of the hydraulic circuit, and changes the inclination angle of the vertical conveyance chain 1 connected to the hydraulic cylinder in the hydraulic circuit, and changes the inclination angle of the vertical conveyance chain 1 connected to the hydraulic cylinder in the hydraulic circuit, and By changing the part of the grain culm, the handling depth can be adjusted according to the length of the grain culm. Further, this handling depth adjusting device is capable of controlling the handling depth by controlling the supply of electricity to the solenoid on and off by operating a manual switch provided on the driver's cab 10.

However, the conventional handling depth adjusting device has the disadvantage that the handling depth may be over-corrected because the automatic switches M and H are opened and closed or the hydraulic cylinder is operated rapidly by operating the manual switch. Ta. When automatically adjusting the handling depth, this overcorrection causes a hunting phenomenon (because the operation is fast, the inclination angle is changed by more than the dead zone width, and the handling depth becomes shallower and shallower repeatedly in a short period of time). cause a changing phenomenon). In addition, in both automatic and manual systems, when overcorrection is made, particularly toward the deep handling side, clogging often occurs in the threshing section, which is inconvenient in that it takes a long time to maintain the threshing section.

The present invention has been made in view of the above circumstances, and is particularly designed to make it possible to change the handling depth little by little by manual operation, thereby preventing excessive adjustment of the handling depth. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to drawings showing embodiments thereof.

FIG. 2 schematically shows the hydraulic circuit of the handling depth adjusting device according to the present invention, and the vertical conveyance chain 1, feed chain 2, etc. whose inclination angles are controlled by the hydraulic circuit. Automatic switches M and H that open and close by detecting the length of the grain culm are arranged in front of the handling cylinder 3, and the automatic switch M is installed near the vertical conveyance chain 1. L is an automatic switch such as a limit switch provided in the middle of the vertical conveyance chain 1, and is for detecting that grain culms are being conveyed in the vertical conveyance chain 1 in a pinched manner. The vertical conveyance chain 1 is connected to a piston rod 4a of a hydraulic cylinder 4 so that its inclination angle can be changed by the operation of a hydraulic cylinder 4 constituting a hydraulic circuit. Reference numeral 5 denotes a 4-port, 3-position switching type electromagnetic directional control valve. When the solenoid SOLr is energized, the electromagnetic directional control valve 5 moves to the switching position r, and the piston rod 4a moves backward as shown by the arrow, and the vertical conveyance chain 1 tilts to the deep handling side, and the solenoid
By energizing SOLl, the electromagnetic directional control valve 5 moves to the switching position l, the piston rod 4a moves forward, the vertical conveyance chain 1 tilts to the shallow handling side, and both solenoids
The hydraulic circuit is configured such that when SOLl and SOLr are not energized, the electromagnetic directional control valve 5 is at the neutral position n, the pressure oil in the hydraulic cylinder 4 is sealed, and its operation is stopped.

Next, the electric circuit for controlling the on/off of energization to the solenoids SOLr and SOLl is constructed as shown in FIG. That is, the solenoids SOLr and SOLl are connected in parallel to surge absorption diodes 14r and 14l, respectively, and these parallel circuits are connected in series with switching transistors 6r and 6l, respectively, to the positive electrode of the battery 7, which is turned on and off by the key switch 12 of the combine. Connected between line and body ground. 8r and 8l are pulse generators constructed using a timer IC commonly known as "555" in astable mode, and each ground terminal A is connected to the body ground, and output terminal C is connected to a switching transistor 6r or 6l. are connected to the base of each. The trigger terminal of the pulse generator 8r is a series circuit of the automatic manual changeover switch 10, the normally open contact La of the automatic switch L, the normally closed contact Mb of the automatic switch M, and the normally open type provided in the driver's cab 10 for automatic recovery. It is connected to the positive electrode line through a parallel circuit with a manual switch 9r. On the other hand, the trigger terminal LO of the pulse generator 8l is connected to the automatic manual changeover switch 10, a series circuit of the normally open contact La and the normally open contact Ha of the automatic switch H, and a parallel circuit with the manual switch 9l similar to the manual switch 9r. and is connected to the positive electrode line. The pulse generators 8r and 8l generate pulses with on times Tr ₁ and Tl 1 and off times Tr ₂ and Tl ₂ , respectively, as shown in _FIGS . emit a signal. And this pulse signal is Tr ₁ <
For example, if Tr ₁ < Tl ₁ , the pulse signal generated by the pulse generator _8r has a smaller on-time total value per unit time than the pulse signal generated by the pulse generator 8l. And Tr ₂ =
The circuit constants of both pulse generators 8r and 8l are selected so that Tl ₂ .

The operation of the apparatus of the present invention constructed as described above is as follows. That is, when the key switch 12 is turned on, the combine harvester is driven, and the grain culm is conveyed while being pinched by the vertical conveyance chain 1, whereby the normally open contact of the automatic switch L is closed. On the other hand, when the grain culm is short, the tip of the grain culm does not come into contact with either automatic switch M or H, so only the normally closed contact Mb of automatic switch M is closed, and when the grain culm is long, At some point, the tip of the tip touches both automatic switches M and H, so the normally open contact Ha of automatic switch H
Only the circuit is closed. Therefore, when the automatic manual changeover switch 10 is turned on to automatically adjust the handling depth, the pulse generator 8r (8l) emits a pulse signal when the grain culm is short (long). Therefore, the switching transistor 6r (6l) is conductive only during the on time of the pulse signal. Figure 4A
is normally closed contact Mb, normally open contact Ha or manual switch 9
It shows the open/closed status of r and 9l, but it is a normally closed contact.
When the closing time of Mb (normally open contact Ha) is instantaneous, a single pulse signal is emitted from the pulse generator 8r (8l) as shown in FIG. 4B and C.
Therefore, the switching transistor 6r (6l) is conductive for the ON time Tr ₁ (Tl ₁ ) of this single pulse signal, and the solenoid SOLr (SOLl) is energized only during this period, so that the electromagnetic directional control valve 5 is switched. to position r(l) and then immediately to neutral position n
to return to. Therefore, the piston cylinder 4a moves backward (forward), and the vertical conveyance chain 1 reaches the ON time Tr ₁
(Tl ₁ ) to the deep handling (shallow handling) side by a predetermined amount corresponding to (Tl 1 ). Here, as mentioned above, Tr ₁ <
Since Tl is ₁ , the amount of correction to the deep treatment side is smaller than the amount of correction to the shallow treatment side.

On the other hand, when the closing time of the normally closed contact Mb (normally open contact Ha) continues for a certain period of time, multiple pulse signals are emitted from the pulse generator 8r (8l), and the pulse signals cause the switching transistor 6r (6l) to close.
l) is intermittently conductive, so the solenoid SOLr
(SOLl) is also energized intermittently, and the electromagnetic directional control valve 5 is repeatedly switched between the switching position r(l) and the neutral position n, and this repeated switching causes the vertical conveyance chain 1 to be This tilting is completed in stages when the normally closed contact Mb (normally open contact Ha) is opened and the pulse signal is turned off. Here, since Tr ₁ < Tl ₁ and Tr ₂ = Tl ₂ , the total energization time per unit time for solenoids SOLr and SOLl is longer than the time when solenoid SOLr is energized than the time when solenoid SOLl is energized. As a result, the tilting speed toward the deep handling side is slower than the tilting speed toward the shallow handling side.

Next, when the automatic manual changeover switch 10 is shut off, the pulse generators 8r and 8l generate pulse signals corresponding to the closing time of the manual switches 9r and 9l as before by closing the manual switches 9r and 9l. , when the manual switch 9r (9l) is instantaneously closed, the pulse generator 8r (8l)
The vertical conveyance chain 1 is tilted toward the deep handling (shallow handling) side by a predetermined amount corresponding to the ON time of the single pulse signal emitted by the manual switch 9r (9r).
l) for a certain period of time, the vertical conveyance chain 1 is moved to the deep handling (shallow handling) side by a predetermined amount corresponding to the ON time of multiple pulse signals emitted by the pulse generator 8r (8l). tilt to. In this case, as before, the amount of correction to the deep side will be smaller than the amount of correction to the shallow side, or the tilting speed to the deep side will be greater than the tilting speed to the shallow side. The processing depth is adjusted manually so that the processing speed is slowed down.

As described above, the handling depth adjustment device of the present invention moves the movable parts for adjusting the handling depth, such as the vertical conveyance chain, to the deep handling side or the shallow handling side by operating a predetermined manual switch. The manual switch 9r or 9 is characterized by having a means for moving the switch by a certain period of time (Tr ₁ or Tl ₁ in the above embodiment).
By operating L so as to instantaneously close the circuit, the handling depth can be adjusted by a small but constant amount, and extremely precise adjustment is possible even by manual operation. In addition, excessive correction is not caused, and troubles associated with it can therefore be avoided. In addition, as mentioned above, if Tr ₁ < Tl ₁ and the amount of movement per time to the deep treatment side is smaller than that to the shallow treatment side, overcorrection to the deep treatment side can be made more effective. In addition, it does not impede the speed with which corrections can be made to the side that is treated poorly.

In the above embodiment, the manual switch 9r or 9
By continuously closing l, the time Tr ₁ or
Although the handling depth can be adjusted by repeating the movement of Tl ₁ , the configuration is such that even if manual switch 9r or 9l is closed continuously, only one pulse is corrected. If desired, one-shot multivibrators may be used as the pulse generators 8r and 8l. It goes without saying that the present invention can also be applied to a manual handling depth adjustment device.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention, in which Figure 1 is a perspective view of the outer shape of the combine, Figure 2 is a schematic diagram of the hydraulic circuit of the device of the present invention, and Figure 3 is an electrical circuit diagram of the device of the present invention. , FIGS. 4A, B, and C respectively show the open/closed states of the automatic switch or manual switch, the pulse signal generated by the pulse generator 8r, and the pulse generator 8l.
This is a time chart showing the pulse signal generated by . 1...Vertical conveyance chain, 2...Feed chain,
3... Handling cylinder, 4... Hydraulic cylinder, 5... Solenoid directional control valve, SOLr, SOLl... Solenoid, 8r, 8l... Pulse generator, 9r, 9l... Manual switch, L,
M, H...Automatic switch.

Claims (1)

[Claims] 1. A handling depth of a combine harvester characterized by having means for moving a movable part for adjusting the handling depth to the deep handling side or the shallow handling side for a certain period of time by operating a predetermined manual switch. Adjustment device.