JPH0451536Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Industrial application field This invention is designed to control the working equipment up and down in order to keep the plowing depth constant when plowing with a working equipment attached to an agricultural tractor. The present invention relates to a depth control device.

(b) Prior Art Many mechanical and electrical depth control devices have been known in the past, but each has its own drawbacks and advantages.

First of all, in the case of a mechanical type, the earlier application filed in 1987-
126301 (Utility Model Publication No. 59-29107) was developed, but in the process of feeding back the movement of the rear cover, which is a plowing depth sensor, to the hydraulic control valve, the arm, link, and push-pull wire were used. They had to be constructed in an interlocking manner, and each of these parts had play and friction, so when put together as a whole, there was a large play and a large amount of sliding resistance, resulting in poor sensitivity and poor accuracy.

On the other hand, if the depth control device is an electric type, a solenoid valve is often used as the control valve, and therefore the position control must also be changed to an electric type. The lever also operated as a switch, which was very different from the operating feel of a conventional operator, so there were drawbacks such as difficulty in getting used to it right away.

Additionally, if all components were electrical, there were other problems, such as incompatibility with tractors without an electric depth control device, and the increased cost of new parts.

(c) Problems to be solved by the invention This invention takes advantage of the advantages of both.The position control is mechanical, the control valve switch actuator is also mechanical, and the depth control bar is mechanical. Only the rotation operation is performed electrically using a control motor.

In a configuration that uses both mechanical position control and electric depth control, for example, in the case of mechanical and mechanical
Compared to the technology of No. 126301 (Japanese Utility Model Publication No. 59-29107), the switching section is important.

That is, when the electric depth control is turned off, if the depth control bar 40 pushes the spool 15 and is stopped in the "raised" or "neutral" position, when operated manually, Rotate the position control lever 4 to the lower position, and then
5 is moved backward, and the spool 15 is pulled back by the biasing spring 61.
Even if you try to push it toward the "lower" side, it will be operated by the aforementioned control motor 9,
Depth control bar 40 in a state of being stopped at a halfway position such as "raised" or "neutral" position
However, since it is in contact with the contact bar 51 of the spool 15, the sliding movement of the spool 15 in the downward direction is obstructed and cannot be done.

In order to improve this point, in the present invention, when the automatic switch 21 is turned off, the control motor 9 finally rotates once again, and the spool 15 can be biased backward to the "lower" position by the biasing spring 61. The depth control bar 40 is retracted to this position, and the rotation of the control motor 9 is then stopped.

(d) Means for solving the problem The problems to be solved by this invention are as described above.
Next, means for solving the problem will be explained.

In a configuration in which a position control mechanism and a depth control mechanism are placed side by side and the control of both mechanisms can be switched, a position control bar 35 and a depth control bar 40 are arranged perpendicularly to the spool 15 of the control valve 12. The central part is configured to be able to selectively abut, one end of the position control bar 35 is configured to move back and forth by the position control lever 4, and the other end of the position control bar 35 is configured to move forward and backward by the rotation width of the lift arm 13. One end of the depth control bar 40 is immovably fixed, and the other end of the depth control bar 40 is configured to move back and forth via the link by rotation of the control motor 9. A rotary encoder 22 for setting the plowing depth is provided at the base of the plowing depth setting lever 5, a plowing depth sensor 1 is provided on the rear cover 2 of the rotary tilling device, and the signals from the rotary encoder 22 and the plowing depth sensor 1 are used to
An automatic switch 2 configured to rotate the control motor 9 in a controlled manner and move the other end of the depth control bar 40 back and forth, and to switch between automatic and manual control.
1, and by operating the automatic switch 21 to the manual side, the depth control bar 40 is retracted to a position where the spool 15 can be retracted to the "lower" position, and then the rotation of the control motor 9 is stopped. It is composed of

(E) Embodiment The problems to be solved by the present invention and the means for solving them are as described above.Next, the structure of the embodiment shown in the attached drawings will be explained.

The configuration of the control device will be explained with reference to the drawing in FIG.

A hydraulic case 6 is mounted on the upper surface of a rear axle case 52 of an agricultural tractor, and a lift arm 13 is driven by a hydraulic cylinder 16 within the hydraulic case 6. Lift link 5 to lift arm 13
3 are connected to each other to move the rotary tiller up and down. Rotary tilling device has tilling claw 1
7. It is composed of a rear cover 2, a tilling cover 54, etc., and a tilling depth sensor 1 is provided on the tilling cover 54.

This tilling depth sensor 1 is rotated by the link 3 as the rear cover 2 is rotated, and the tilling depth, which is the distance between the bottom surface of the rear cover 2 and the tip of the tilling claw 17, is determined by the change in the rotation angle of the tilling depth sensor 1. I'm taking it out and replacing it.

20 is a control panel, and this control panel 20
is fixed to the dart board panel surface of an agricultural tractor. Automatic switch 2 on control panel 20
1 is provided, and the automatic switch 21 is turned off.
, "Small" pulse width, and "Large" pulse width.
It acts as a position switch.

The tilling depth value of the depth control is set by rotating the tilling depth setting lever 5. As shown in FIG. 3, the plowing depth setting lever 5 is equipped with a voltage converter such as a variome or rotary encoder at its tip, and is used to set the plowing depth.

The controller 7 determines the plowing depth set value by the plowing depth setting lever 5 and the feedback value from the plowing depth sensor 1, issues forward/reverse rotation commands to the control motor 9, and rotates the depth control bar 40 back and forth.

Since the commands sent to the control motor 9 are only forward and reverse rotation commands, the spool 15 of the control valve 12 is actually "raised", "neutral" and "lowered".
The position of the valve is detected by the valve position detection switch 10 and fed back to the controller 7, which determines whether to continue rotating the control motor 9 in the forward direction, stop it, reverse direction, or change it.

11 is a rack and pinion case in which a rack and pinion device for slowing down the rotation of the control motor 9 is housed.

19 is a back switch that is turned ON when the gear shift lever 8 of the agricultural tractor is set to reverse;
Reference numeral 8 designates a position control switch that is turned on when the position control lever 4 is raised to the highest position, such as when going around the edge of a field.

The specific structure around the hydraulic case 6 will be explained based on the drawings of FIGS. 2, 3, and 4. On the left side of the hydraulic case 6, there is a control motor fixing plate 25.
A pinion rack case 11 including a pinion 23 and a rack 24 is fixed to the control motor fixing plate 25, and a control motor 9 and a valve position detection switch 10 are fixed to the pinion rack case 11.

Further, as shown in FIG. 3, a lever guide 46 is provided on the right side of the hydraulic case 6, and a position control lever 4 is attached to this lever guide 46.
and the reverse setting lever 5 is guided.

A position control lever switch 18 that is turned ON when the position control lever 4 is in the highest position is also provided on the lever guide 46. Also, a rotary encoder 22 for setting tillage depth.
is also fixed to the lever guide 46.

The tilling depth setting lever 5 is a rotary encoder 22
The control bar 40 and the spool 15 are not directly moved, but are rotated to change the voltage value.

On the other hand, position control lever 4
The arm 37 and link 36 in Fig. 4 are rotated.
, the right end of the position control bar 35 is rotated to set the position control position. On the other hand, when pressure oil enters the hydraulic cylinder 16 and the lift arm 13 rotates, the arm 34 in FIG. 4 rotates via the link 45 and arm 44 in FIG. The left end of the position control bar 35 moves in the opposite direction to the direction set by the position control lever 4, returning the center position of the control bar to the neutral position of the spool and stopping control.

In the depth control device of the present invention, the tilling depth is set by electrically setting the rotary encoder 22 by rotating the tilling depth setting lever 5, and comparing this with the feedback tilling depth value from the tilling depth sensor 1. , the control motor 9 gradually moves the spool 15 in the upward or downward direction.

The rotation of the control motor 9 is controlled by the pinion 2.
3 causes the rack gear 24 to rotate, and via the arm and link 26, the arm 42 in the hydraulic case 6 as shown in FIG. 4 rotates, and via the link 41, the right end of the depth control bar 40 rotates. It is.

Since the left end of the depth control bar 40 is not related to the plowing depth setting lever 5, in the present invention, it is fixed at approximately the center and does not rotate during normal control. However, if there is an electrical failure in the control circuit and the control motor 9 stops at the raised position of the spool 15, and the rotary tiller cannot be lowered by the position control lever 4, the lever guide 45 on the right side The remaining fixed position of the depth control lever 47 is moved back to the lowering side of the spool 15 by removing the butterfly bolt, so that only the position control can be used at the minimum.

By rotating the depth control lever 47, the depth control bar 40 is moved backward in the downward direction via the arm 38 and the link 39. Reference numeral 51 denotes a contact bar, which is provided in the vertical direction so that both the depth control bar 40 and the position control bar 35 can come into contact with the spool 15.

The above is the general configuration of the depth control device of the present invention, and the present invention describes the configuration in non-automatic mode of a control system in which such a mechanical position control device and an electric depth control device are installed side by side. It is related to.

In other words, when the automatic switch 21 in FIG. 1 is turned OFF to stop the automatic mode, in other words,
When switching to manual mode, the valve position detection switch 10 is set in the switch-down position so that the control motor 9 is stopped when the control bar 40 is in the spool-down position so that manual control can be performed immediately using the position control lever 4. When the position is reached, turn on the control motor.
I turned it off.

That is, the position control bar 3 in FIG.
5. Move the right end of the depth control bar 40 in the "lower" direction by forward rotation of the control motor 9, and the arm 42/link 41 moves the control bar in the right direction in the drawing, that is, in the lowering direction of the spool 15. The depth control bar is moved back from the position control bar 51 so that it does not touch the bar 51.

This allows the position control lever 4 to control the full range of vertical movement of the lift arm.

Also, position control lever switch 1
8 is OFF and the automatic switch 21 is turned ON, the automatic mode is activated for the first time, and the position control lever switch 18 is turned ON.
At that point, the depth control bar 4
Regardless of the zero position, the control motor 9 is configured to stop.

This point will be explained using the flowchart shown in FIG. PCL is the position control lever switch 18, and when the position control lever switch 18 is ON, it means that the position control lever 4 has been turned all the way in the upward direction. Since the rotary is often in the raised position when traveling, the automatic mode is set to OFF.

Position control lever switch 18
When the switch is turned off, the automatic switch 21 is turned on again.
It is configured to go into automatic mode when turned on.

ETF is a dead zone flag and AUTF is an auto flag. If both are turned on when the position control lever switch 18 is turned on, the automatic mode will be turned off at that point, the depth control will no longer work, and the control motor 9 will be turned on. The vehicle stops at a position that cannot be specified during depth control.

However, since the position control lever 4 is rotated to the highest position, the right end of the position control bar 35 is positioned at the forefront, so no matter where the depth control bar 40 stops, the position control bar takes priority.

As a result, when the position control lever 4 is moved to the highest position, the automatic depth control state is interrupted and position control is prioritized. Further, even if the position control lever 4 is lowered and the position control switch 21 is OFF, the automatic mode is turned off when the automatic switch 21 is OFF.

In this case, since it is assumed that the operator will manually control the position, the control motor 9 will be rotated until the valve position detection switch 10 reaches the lowered position, and then stopped at the lowered position, as described above. The configuration is such that the left end of the depth control bar 40 is moved back the most, and the position control bar 35 is given priority over the entire area.

The above is the operation of the main part of the present invention. When the automatic switch is ON, the subsequent control is such that when the back switch 19 is turned ON, automatic is turned OFF, and the control motor is turned off until the valve position detection switch is turned up. 9, wait several hours until the lift arm 13 is sufficiently raised in the raised position, then return the valve position to the neutral state and stop the control motor.

This prevents the lift arm from lowering even if the shift lever 8 is moved forward or returned to neutral. When performing automatic control again, it is necessary to operate the return switch.

When the back switch is OFF, select the valve size using PLF/PSF and set the revised plowing depth value V _S ,
_{( H ​ ​ ​ ​ ​} )(d)
The corresponding controls (E), (F), and (B) are performed.

(f) Effects of the invention Since the invention is constructed as described above, it has the following effects.

First, in the non-automatic mode with the automatic switch 21 turned OFF, the depth control bar 4
Since the control valve 12 is moved back to a position where it does not control the control valve 12 at all, the position control lever 4 can be operated immediately.

Second, the depth control bar 40, which is an electrical depth control system, is retracted to a position where it does not interfere with the operation of the position control bar 35, which is a mechanical position control system. The position control and electric depth control can now be used together, making it possible to obtain both the same position control as the conventional operation feeling and a depth control device with higher precision and faster response. .

Thirdly, since the electric depth control is constructed without using a solenoid valve, the same parts as those of the conventional mechanical depth control can be used, reducing costs. be.

[Brief explanation of the drawing]

Fig. 1 is a control block diagram of the depth control device of the present invention, Fig. 2 is a left side view of the hydraulic case showing the control motor section, Fig. 3 is a right side view of the hydraulic case showing the control lever section, and Fig. 3 is a right side view of the hydraulic case showing the control lever section. Fig. 4 is a bottom view of the hydraulic case showing the control bar portion, and Fig. 5 is a part of the control flowchart of the depth control. 1... Tilling depth sensor, 4... Position control lever, 7... Controller, 9... Control motor, 12... Control valve, 13... Lift arm, 18... Position control lever switch, 21... Automatic switch.

Claims (1)

[Scope of utility model registration request] In a configuration in which a position control mechanism and a depth control mechanism are placed side by side and the control of both mechanisms can be switched, a position control bar 35 and a depth control bar 40 are arranged perpendicularly to the spool 15 of the control valve 12. The central part is configured to be able to selectively abut, one end of the position control bar 35 is configured to move back and forth by the position control lever 4, and the other end of the position control bar 35 is configured to move forward and backward by the rotation width of the lift arm 13. One end of the depth control bar 40 is immovably fixed, and the other end of the depth control bar 40 is configured to move back and forth via the link by rotation of the control motor 9. A rotary encoder 22 for setting the plowing depth is provided at the base of the plowing depth setting lever 5, a plowing depth sensor 1 is provided on the rear cover 2 of the rotary tilling device, and the signals from the rotary encoder 22 and the plowing depth sensor 1 are used to
An automatic switch 2 configured to rotate the control motor 9 in a controlled manner and move the other end of the depth control bar 40 back and forth, and to switch between automatic and manual control.
1, and by operating the automatic switch 21 to the manual side, the depth control bar 40 is retracted to a position where the spool 15 can be retracted to the "lower" position, and then the rotation of the control motor 9 is stopped. A depth control device for an agricultural tractor characterized by the following configurations.