JPH0238578Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a hydraulic circuit switching mechanism of a hydraulic control device for a rice transplanter.

Generally, when planting seedlings, a rice transplanter automatically adjusts the height of the machine equipped with the planting tool against the ground to always be constant, so that floating seedlings or seedlings are not planted too deep even if the field is uneven. We are planting seedlings in a controlled manner.
The automatic control involves sliding a float over the field and operating a hydraulic control device depending on the vertical position of the float to raise and lower the machine, thereby keeping the height of the machine constant above the ground.

However, when an emergency is required, such as when turning on a headland, automatic control based on float detection is interrupted and manual control is required to manually move the aircraft up and down to a desired position.

In this way, in order to link automatic control based on float sensing and manual control, which requires manually raising and lowering the aircraft, to a single switching valve and using a link mechanism, the float sensing operation must be activated during automatic control. Since the situation is reversed during manual control, it is necessary to ensure that the respective link mechanisms can perform switching operations under both controls reliably and smoothly without interfering with each other.

Therefore, in the hydraulic control device for a rice transplanter of the present invention, the hydraulic control mechanism 9, which is designed to automatically control the height of the machine body 2 from the ground to be constant by detecting the vertical position of the float 1, can be manually operated. In a rice transplanter configured to be able to switch between automatic control and automatic control,
An input portion of a sensing lever 24 pivotally connected to the body 2 is interlocked with the float 1, and an input receiving portion 28a of a valve operating body 28 connected to the switching valve 16 of the hydraulic control mechanism 9 is located near the sensing lever 24. The sensor lever 24 is configured to face the output portion 27 of the sensor lever 24 so as to be able to come into contact with and release from the sensor lever 24, and a spring 32 is provided between the body 2 and the valve operating body 28 side to return the valve operating body 28 to the downward operating direction of the body 2. The valve operating body 28 is provided with a structure so as to maintain the contact state between the valve operating body 28 and the sensing lever 24 and urge the float 1 in the downward direction when switching to the automatic control state. In the automatic control state, the valve operating body 28 is retracted to the aircraft lowering operation direction side,
A locking body 34 that moves the valve operating body 28 against the bias of a spring 32 in a manual control state is provided so as to be able to reciprocate in one direction.
It is an object of the present invention to provide a hydraulic control device for a rice transplanter which has a simple structure and can perform switching operations in a timely manner without interfering with each other by interlocking and connecting the two to an operating member 11 provided in a control section.

Next, an embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, a rice transplanter main body 2 (body) whose one end is rotatably pivoted to the rear part of a float 1 is supported at its intermediate portion by wheels 3. Power is transmitted to the wheels 3 from an engine 4 via a transmission 5. Further, this wheel 3 is configured to be able to swing up and down around a transmission case 5, and its position is regulated by a hydraulic cylinder 6 via a rod 7 and a link 8. This hydraulic cylinder 6 is controlled by a hydraulic control mechanism 9, which is manually controlled via a wire 12 by an operating member 11 disposed near the handle 10 at the rear of the rice transplanter body 2. It is possible to switch between automatic controls and manually control up and down strokes and fix them. (See Figure 4) The hydraulic control mechanism 9 disposed on the fuselage 2, which is the main part of the present invention, will be explained with reference to Figures 2 to 8. The hydraulic control mechanism 9 includes a single-acting hydraulic cylinder 6 that is hydraulically operated only in the forward stroke, and a tank 13 and a pump 1 shown in FIG. 8 that supply pressure oil to the hydraulic cylinder 6.
4, a pressure regulating valve 15, a switching valve 16, a link mechanism 17 for controlling the switching valve 16, the operating member 11, and the wire 12. And those piping are as shown in Figure 8.
A pressure regulating valve 15 connects a pipe line 18 connecting the tank 13 and the pump 14, and the pump 14 and the switching valve 16.
a return oil pipe 20 that connects the switching valve 16 and the tank 13, a return oil pipe 21 that connects the pressure regulating valve 15 and the tank 13, and the switching valve 16 and the hydraulic cylinder 6. It is composed of a conduit 22 that connects the

Also, to explain the link mechanism 17, the fuselage 2
The middle part of a sensing lever 24 is rotatably mounted on the rotating shaft 23 of the switching valve 16, which is a rotary valve fixed to the rotary valve. rod 2
The rod 2 is connected to the float 1 through the rod 5, and the amount of fluctuation in the vertical rotation of the float 1 about the pivot point with the fuselage 2 at the rear of the float 1 is controlled by the rod 2.
5 into the rotation angle of the sensing lever 24. And the float 1 and the fuselage 2
are connected by a pair of connecting links 26, 26 which are bent freely in order to stabilize the operation of the float 1, and the amount of vertical fluctuation of the float 1 is:
As shown in FIG. 4, the moving height H of the upper limit moving position and the lower limit moving position is set.

On the other hand, the other end of the sensing lever 24 is provided with an output portion 27 that is bent in the thickness direction thereof. This output section 27 is connected to the switching valve 16.
An input receiving part 28a at one end of a valve operating body 28 whose intermediate portion is fixed to the rotating shaft 23 of the valve operating body 28 is configured to be able to come into contact with and be separated from the input receiving part 28a of the valve operating body 28 so as to be able to be pressed from above.

A pin 29 extending in the thickness direction of the valve operating body 28 is implanted at the other end of the valve operating body 28 . This pin 29 faces into and engages with a long hole 31 at the upper end of an arm 30 whose lower end is rotatably supported on the body 2.

Further, the arm 30 is constantly biased in the direction of arrow A in FIG. 4 by a spring 32 whose one end is fixed to the body 2. As a result, the valve operating body 28 is always energized via the pin 29 so as to be returned to the direction in which the body 2 is lowered, as will be described later. Further, a pin 33 is implanted in the intermediate portion of the arm 30, and this pin 33 is connected to a long hole 35 of a locking body 34 provided at one end of the wire 12.
It is designed to slide inside. The other end of the wire 12 is connected to the operating member 11, and the locking body 34 is configured to reciprocate in one direction when the operating member 11 is operated.

The positional relationship between the elongated hole 35 of the locking body 34 of the wire 12 and the pin 33 of the arm 30 is
When the pin 33 is moved to the automatic position 36, the pin 33 is located approximately at the center of the elongated hole 35, and when the operating member 11 is moved to the manual raise position 37, the pin 33 is located at the right end of the elongated hole 35, as shown in FIG. As a result, the pin 33 is pulled, and the arm 30 moves by a certain angle in the direction of arrow B. Further, when the operating member 11 is moved to the manual neutral position 38 as shown in FIG. 6, the arm 30 further moves by a certain angle in the direction of arrow B. Further, as shown in FIG. 7, when the operating member 11 is moved to the manual lowering position 39, the arm 30 further moves by a certain angle in the direction of arrow B.

On the other hand, to explain the pipeline switching mechanism 41 of the rotor 40 of the switching valve 16 with reference to FIG. 4, the pressure oil inlet 42 is provided in the center of the rotor 40, and the cylinder port 43 and tank port 44 are respectively They are provided 180 degrees opposite each other around the circumference.

Then, with the float 1 set at a position approximately 1/2 of the moving height H of the upper limit movement position and the lower limit movement position of the float 1 (solid line position in Fig. 4), the rotor 40 is moved as shown in Fig. 4-2. The pressure oil passage 45 for both manual and automatic use, which has a large passage cross-sectional area, is connected to the cylinder port 4.
The automatic cylinder return passage 4 has a small passage cross-sectional area.
6 is also slightly removed from the cylinder port 43 β1
stipulated in At that position, the automatic tank return passage 47, which has a large passage cross-sectional area, is set at a position γ1 that slightly opens into the tank port 44, and supplies pressure oil to the tank 1.
3 to unload it.

On the other hand, the manual cylinder return passage 48, which has a passage cross-sectional area determined by an appropriate manual lowering speed, is set at a position θ1 that is far away from the cylinder port 43, and also has a large passage cross-sectional area. The flow path 49 is set at a position δ1 that is far away from the tank port 44.

Now, when automatically controlling the height of the machine body 2 relative to the field, if the operating member 11 is set to the automatic position 36 as shown in FIG. pin 33
The pin 33 is retracted from engagement with the elongated hole 35 so that the pin 33 is located approximately at the center of the elongated hole 35. (At this time, the float 1 is located at the solid line position H/2.) When the arm 30 and the wire 12 are thus set in a free state, the valve operating body 28 is urged in the direction of arrow D by the action of the spring 32. Therefore, the input receiving portion 28a is brought into contact and pressure contact with the lower surface of the output portion 27 of the sensing lever 24, and by maintaining this contact state, the float 1 is urged in the downward direction.

When the height of the aircraft body 2 becomes lower with respect to the field, the float 1 rises. Due to this rising action of the float 1, the sensing lever 24 is rotated in the direction of arrow C via the rod 25. Therefore, the output portion 27 is pushed against the spring 32 to the valve operating body 28.
Press down the input receiving part 28a of the valve operating body 28
Rotate in the direction of arrow C. Therefore arm 3
0 also moves in the direction of arrow B.

The rotor 40 is in the neutral position (Fig. 4-2) due to the rotation of the valve operating body 28 in the direction of arrow C.
is rotated in the direction of arrow C as shown in FIG. 4-1, so the automatic tank return passage 47 is closed γ2, and the manual and automatic pressure oil passage 45 is slightly opened α2. Therefore, since the cross-sectional area of the opening of the flow passage is small, the flow rate per unit time flowing from the pressure oil inlet 42 into the cylinder port 43 is small. As a result, the hydraulic cylinder 6 slowly moves forward, rotates the wheels 3 downward, and raises the body 2. Along with this, the float 1 descends and returns to the position shown by the solid line in FIG. Follow it.

Therefore, the rotor 40 returns to the neutral position shown in FIG. 4-2, so the cylinder port 43 is closed and the hydraulic cylinder 6 is stopped, and the tank port 4 is closed.
4 and the pressure oil inlet 42 are in slight communication to unload the pressure oil.

On the other hand, if the height of the aircraft 2 becomes higher than the field,
Float 1 descends. As the float 1 rotates, the sensing lever 24 rotates in the direction of arrow D in FIG. 4 via the rod 25. Therefore, a gap is created between the output section 27 and the input receiving section 28a of the valve operating body 28. Due to this gap, the arm 30 swings in the direction of arrow A in FIG. 4 due to the biasing force of the spring 32, so that the valve operating body 28 rotates in the direction of arrow D. As the valve operating body 28 rotates, the rotor 40 of the switching valve 16 rotates in the direction of arrow D as shown in Fig. 4-3, so that the rotor 40 in the neutral position (Fig. 4-2) The automatic cylinder return passage 46 of 40 is located at a position β3 where it communicates with the cylinder port 43, and the automatic tank return passage 47 is located at a position γ3 where it communicates with the tank port 44 with a large passage cross-sectional area.

Since the piston of the hydraulic cylinder 6 retreats due to the weight of the aircraft, the oil in the cylinder passes through the automatic cylinder return flow path 46 with a small cross-sectional area and returns to the automatic tank along with the oil unloaded from the pump 14. The water flows out from the flow path 47 into the tank 13 .

Therefore, since the amount of oil flowing through the automatic cylinder return flow path 46 per unit time is small, the piston of the hydraulic cylinder 6 slowly retreats, and as a result, the wheels 3 slowly rotate upward, so that the rice transplanter main body 2
becomes lower.

When the body 2 becomes lower, the float 1 rises again, so the sensing lever 24 rotates in the direction of arrow C in FIG. 4 via the rod 25.

In conjunction with this, the valve operating body 28 is also rotated in the direction of arrow C by the output section 27 together with the arm 30, so that the rotor 40 of the switching valve 16 returns to the neutral position shown in FIG. 4-2. Then, the cylinder port 43 is closed and the hydraulic cylinder 6 is stopped, and the tank port 44 and the automatic tank return passage 47 are slightly communicated with each other to unload the pressure oil. Next, a case will be described in which the height of the machine body 2 relative to the field is manually controlled.

Now, when raising the body 2 by manual control, as shown in FIG. 5, when the operating member 11 is set to the manual raising position 37, the locking body 34 of the wire 12 moves to the left and pulls the pin 33. Therefore, the arm 30 swings in the direction of arrow B against the spring 32, and accordingly, the valve operating body 28 moves in the direction of arrow C.
rotate in the direction. At this time, this valve operating body 2
The input receiving part 28a of 8 is the output part 2 of the sensing lever 24.
7, the valve operating body 28 and the sensing lever 24 move differently.

On the other hand, due to the rotation of the valve operating body 28 in the direction of arrow C, the rotor 40 is moved to the fourth position as shown in FIG. 5-1.
- Rotate in the direction of arrow C from the neutral position shown in Figure 2. The manual and automatic pressure oil passage 45, which was located at the α1 position (Fig. 4-2), is located at the α4 position (Fig. 4-2).
1) and communicates with the cylinder port 43. Further, since the automatic tank return channel 47 moves from the γ1 position (Fig. 4-2) to the γ4 position (Fig. 5-2), the tank port 44 is closed.

Therefore, the pressurized oil sent from the pump 14 reaches the hydraulic cylinder 6 through the pressure oil passage 45 having a large cross-sectional area and the cylinder port 43, so that the piston of the hydraulic cylinder 6 advances rapidly. As a result, the wheels 3 rapidly move downward, and the aircraft 2 quickly rises.

When the operating member 11 is brought to the manual neutral position 38, the wire 12 further rotates the arm 30 in the direction of arrow B as shown in FIG. 6 via the locking body 34. Due to this rotation of the arm 30, the valve operating body 28 further rotates in the direction of arrow C, so the rotor 40, which was in the manual raise position (Fig. 5-1), further rotates in the direction of arrow C and the position of α4. Position (No. 5-1
The manual and automatic pressure oil flow path 45 in Figure 6-1 is moved to the α5 position to close the cylinder port 43, and the manual tank return flow path 49 is moved to the position α5 as shown in Figure 6-1. 6th - from position δ4 in the figure
1, the manual tank return channel 49 slightly communicates with the tank port 44 and unloads the pressurized oil sent from the port 14. Therefore, the hydraulic cylinder 6, which was rapidly moving forward, stops, and the machine body 2 is stopped and fixed. When lowering the fuselage 2 by manual control, when the operating member 11 is set to the manual lowering position 39 as shown in FIG. 7, the locking body 34 of the wire 12 is moved further to the left than the position shown in FIG. Move and pull the pin 33. Therefore, the arm 30 moves against the spring 32 in the direction of arrow B.
The valve operating body 2 swings in the direction of the
8 rotates in the direction of arrow C, and at the same time, the rotor 40 rotates in the direction of arrow C as shown in Figure 7-1, so that the manual cylinder return which was at the position θ5 at the time of manual neutralization in Figure 6-1 The flow path 48 is the 7th-1
Move to position θ6 in the figure and press cylinder port 43.
communicate with. Also, due to the rotation of the rotor 40, the manual tank return passage 49, which was at the manual neutral position (Fig. 6-1) at the position δ5, is moved to the position δ6 as shown in Fig. 7-1. It communicates with the tank port 44 through a large flow passage cross-sectional area.

Since the piston of the hydraulic cylinder 6 retreats due to the weight of the aircraft, the oil in this cylinder passes through the manual cylinder return passage 48, which has a passage cross-sectional area calculated from an appropriate lowering speed, to the pump 14.
The oil flows out into the tank 13 from the manual tank return channel 49 together with the oil unloaded from the tank.

Therefore, the amount of oil flowing through the manual cylinder return passage 48 per unit time can be determined by an appropriate manual lowering speed, so the hydraulic cylinder 6 retreats at an appropriate speed, and as a result, the wheels 3 rotate upward. Therefore, the rice transplanter main body 2 becomes weak.

After lowering the rice transplanter body 2 in this way, when the operating member 11 is returned to the manual neutral position 38, the wire 12 is loosened, and the arm 30 rotates in the direction of arrow A to the position shown in FIG. , as the valve operating body 28 rotates in the direction of arrow D, the rotor 40 rotates in the direction of arrow D, and the rotor 40 rotates in the direction of arrow D.
At the neutral position shown in the figure, the hydraulic cylinder 6, that is, the wheels 3 are stopped, and the vertical position of the body 2 is fixed. In short, the hydraulic circuit switching mechanism of the hydraulic control device for a rice transplanter according to the present invention is designed to automatically control the height of the machine body 2 from the ground to be constant by detecting the vertical position of the float 1. In a rice transplanter configured to be operable and switchable between manual control and automatic control, the input part of a sensing lever 24 pivotally connected to the body 2 is interlocked with the float 1, and the above-mentioned hydraulic pressure is connected near the sensing lever 24. The input receiving part 28a of the valve operating body 28 connected to the switching valve 16 of the control mechanism 9 is connected to the sensing lever 2.
A spring 32 is provided between the fuselage body 2 and the valve operating body 28 side to return the valve operating body 28 to the downward operating direction of the fuselage body 2. When the state is switched to the automatic control state, the valve operating body 28 and the sensing lever 24 are kept in contact with each other to urge the float 1 in the downward direction. In this state, the valve operating body 28 is retracted to the side of the aircraft lowering operation direction, and in the manual control state, the valve operating body 28 is moved by the spring 3.
A locking body 34 that is operated to move against the bias of 2 is provided so as to be able to reciprocate along one direction, and the locking body 34 is interlocked and connected to the operating member 11 provided in the control section.
The sensing lever 24 and the valve operating body 28 have a structure in which they come into contact only in one direction, so the structure is extremely simple and there is no failure. During automatic control, the sensing lever 24 makes contact with the valve operating body 28 when the float 1 is moving upward. When the float 1 is pushed down and the float 1 is lowered, the valve operating body 28 contacts and follows the sensing lever 24 due to the biasing force of the spring 32, and in either case, the valve operating body 28 can always operate accurately without backlash, and the timing of hydraulic switching is achieved. The hydraulic circuit can be switched with certainty. Furthermore, when switching to manual control, only the valve operating body 28 is operated in the direction of separating from the sensing lever 24, regardless of the sensing lever 24 from the float 1, against the bias of the spring 32, so the operation is light and quick. Can be done.

The locking body 34 for manual operation is configured to be able to reciprocate along one direction, and the locking body 34 for manual operation is
engages with the valve operating body 28 side and the spring 32
Since the engaging body 34 is pulled only in one direction against the force, the structure of the engaging body 34 can be simplified, it is inexpensive, there is no failure, and accurate manual control is possible at all times. Furthermore, since the engaging body 34 is constructed to be pulled in only one direction against the spring 32, it can be easily operated at the control section, and therefore operations that require skill such as when turning on a headland can be performed using the automatic control mechanism. Coupled with the link structure, it can be done easily and quickly.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and Fig. 1 is an overall side view thereof, Fig. 2 is a plan view of essential parts, Fig. 3 is a front view thereof, Fig. 4 is a side view thereof, and Fig. 4-1. Figures 4-2 and 4-3 are explanatory diagrams of the pipe switching mechanism;
Figure 5, Figure 5-1, Figure 6, Figure 6-1, Figure 7
Figure 7-1 is an explanatory diagram showing the operating state of the main parts,
FIG. 8 is a piping system diagram. 9...Hydraulic control mechanism, 11...Operation member, 24
...Sensing lever, 28...Valve operating body, 27...
...output part, 28a...input receiving part, 32...spring, 34...locking body.

Claims (1)

[Scope of utility model registration request] In a rice transplanter in which a hydraulic control mechanism 9, which is designed to automatically control the height above the ground of a body 2 to be constant by detecting the vertical position of a float 1, can be operated manually and can be switched between manual control and automatic control. , an input part of a sensing lever 24 pivotally connected to the body 2 is interlocked with the float 1, and near the sensing lever 24 there is an input receiving part 28a of a valve operating body 28 connected to the switching valve 16 of the hydraulic control mechanism 9. is configured to face the output part 27 of the sensing lever 24 so that it can come into contact with and release from it, and the body 2 and the valve operating body 28
A spring 32 is provided between the side and the valve operating body 28 to return the valve operating body 28 to the downward operating direction of the fuselage 2, and when the automatic control state is switched, the valve operating body 2
8 and the sensing lever 24 to urge the float 1 in the downward direction, and furthermore, the valve operating body 28 side is provided with a direction in which the valve operating body 28 is operated to lower the aircraft in the automatic control state. A locking body 3 that is retracted to the side and moves the valve operating body 28 against the bias of a spring 32 in the manual control state.
A hydraulic control device for a rice transplanter, characterized in that a locking body 34 is provided to be reciprocally movable along one direction, and the locking body 34 is interlocked and connected to an operating member 11 provided in a control section.