JPS6310966B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention includes a seedling planting device machine frame equipped with a planting device that divides and plants seedlings from a seedling tank, and running wheels that touch the plowing surface of the field and drive the vehicle body for traction. By installing a traveling machine frame and a float that floats and slides above the topsoil surface of the field, the relationship between the above three parts can be adjusted to prevent the float from rising too close to the seedling-planting machine frame and causing seedlings to be planted incorrectly. If this becomes impossible, the traveling machine frame side will lower or the seedling planting device machine frame side will rise to resolve this problem, and conversely, if the float descends and the seedlings are planted too far apart, resulting in inappropriate seedling planting, the traveling machine frame side will rise. The present invention relates to an operating device for a rice transplanter that is equipped with a hydraulic control device to eliminate this problem by lowering the seedling transplanter frame or lowering the seedling transplanter frame.

Conventionally, the switching valve of the hydraulic control device in this type of rice transplanter has been designed to be able to be switched manually from the operating position. Three position setting states can be selected: a raised state in which the device frame is set high above the surface of the field, and a descended state in which the seedling planting device frame is further lowered and stopped. However, being able to choose from three positions is extremely disadvantageous, especially if you set it to the lowered position, the automatic operation may work unexpectedly when the number of seedlings in the seedling tank decreases and you need to replenish them. Since the seedling planting device is stable at a low position without any movement, it can be done very accurately and easily, but when you want to start planting again after replenishing the seedlings, you can automatically control it from the lowered position by operating the hydraulic switching lever. If you forget this switching operation and restart seedling planting, the float will sink into the topsoil of the field and push mud, burying the seedlings that have already been planted. If you are unable to reliably plant the plants,
Furthermore, there were drawbacks such as the engine stalling.

This invention eliminates the drawbacks of the conventional rice transplanter described above, and also when the hydraulic switching valve restricts the seedling transplanter frame side to a direction where upward movement control is not performed by operation of the clutch lever system during traveling or planting. It is an object of the present invention to provide an ideal operation device for a rice transplanter that allows easy operation of a clutch lever system and allows the machine frame side of the seedling transplanter to be smoothly lowered and stopped.

To achieve this objective, the present invention has taken the following technical measures.

That is, the present invention provides a seedling planting device machine frame A that is equipped with a planting device 9 that divides and plants seedlings from a seedling tank 8.
The above-mentioned seedling planting device machine frame A is provided with a traveling machine frame B equipped with running wheels 11 that are in contact with the plowing surface of the field and drive the vehicle body for traction, and a float 22 that floats and slides on the surface of the topsoil of the field. The relationship between the traveling machine frame B and the float 22 is determined by the hydraulic system when the float 22 rises too close to the seedling planting device machine frame A and approaches beyond the predetermined appropriate seedling planting range. In a rice transplanter equipped with a hydraulic control device that is linked to prevent excessive approach and, conversely, to prevent seedlings from descending and separating too far from the proper planting range, this rice transplanter is connected to the switching valve 18 of the hydraulic device. An elongated hole 49 is formed in the actuating plate 19, which is freely rotatable and operates the switching valve 18, and is fitted into the elongated hole 49, so that the actuating plate 19 can move freely and in one direction of rotation. A pin 47 is provided that can be operated when the side is restricted and movement is prevented, and this pin 47 is connected to the hydraulic switching lever 30 provided near the rice transplanter operating position, and a spring 48 is used to keep the pin 47 always attached. The seedling planting device machine frame A is configured such that the oil pressure switching lever 30 does not restrict the actuating plate 19 with the pin 47.
In the automatic control state where the pin 4 automatically controls the elevation and
The oil pressure switch is switchable between three position setting states: a rising state in which the pin 47 is moved to the tension side to rise and stop, and a descending state in which the pin 47 is rotated by a spring 48 to descend and stop. The lever system and the clutch lever system for running the rice transplanter or planting the rice transplanter are connected to each other. When the clutch lever is powered on, the actuating plate 19 moves freely within a certain range, and the hydraulic switching valve 18 is connected to the seedling transplanter machine frame. The operation device of the rice transplanter is characterized in that the operating device of the rice transplanter is configured such that the rice transplanter A is prevented from being set in the descending state, and in the power "off" state, the rice transplanter is configured to be set in the descending state by the tension of the spring 48. .

This invention will be described in detail based on an embodiment shown in the drawings.

First, to explain the configuration of the walk-behind rice transplanter shown in FIG. It consists of a rice transplanter case 5, a planting frame 7 with a control handle 6 attached, a seedling tank 8, a planting device 9, etc., and constitutes the main part of the rice transplanter. The seedling tank 8 is provided along the control handle 6 so as to be able to reciprocate from side to side.
The planting device 9 is mounted on both left and right sides of the planting mission case 5 so as to move up and down.
It is provided so that the seedlings placed in the seedling tank 8 are divided and planted.

B is a traveling machine frame, and in a walking type rice transplanter, this chain case 10 and chain case 1 are attached to the left and right sides of the traveling transmission case 3 so as to be movable up and down.
It consists of a running wheel 11 mounted on an axis on the tip end side of the wheel. This chain case 10 has a balance rod 13, a rod 14, and
The chain case 10 is connected via an arm 15 fixed to the chain case 10.

Reference numeral 16 denotes a hydraulic cylinder, which is vertically installed in the upper part of the traveling transmission case 3 with its base facing forward, and the piston 12 inserted through this cylinder is directed rearward. Oil is fed into the base chamber of this hydraulic cylinder 16 from a hydraulic gear pump 17 via a hydraulic switching valve 18.

The hydraulic switching valve 18 is shown in FIGS. 13, 14,
As shown in FIG. 15, the oil from the pump 17 is sent into the hydraulic cylinder 16 and the piston protrudes, causing the balance rod 13 and the rod 1 to move.
4. The left and right wheels 11 are lowered via the arm 15, and the seedling planting device A is raised. 14th
In the case shown in the figure, the oil from the pump 17 is directly returned into the traveling transmission case 3 which also serves as a hydraulic tank, so that the traveling wheels 11 are set at a predetermined position without any vertical movement. In FIG. 15, the oil from the pump 17 returns to the traveling mission case 3, and the oil in the hydraulic cylinder 16 also returns to the traveling mission case 3 under the load applied to the piston 12, and the traveling wheels 11 After rising, the seedling planting device A is in a state of descending.

The hydraulic switching valve 18 is connected via a connecting rod 20 and a valve arm 21 to an actuating plate 19 which is pivotally supported on the side surface of the traveling transmission case and swings.

Reference numeral 22 indicates a center float, and reference numeral 23 indicates a side float, both of which are attached at the rear to an adjustment arm 24 provided on the planting frame 7 so as to be able to move up and down, via a pin 25, and at the tip end by an expansion/contraction link 26a. The floats 22 and 23 are mounted so that their front sides can freely move up and down.

26 is a connecting rod that connects the central float 22 and the actuating plate 19, and when the central float 22 moves up significantly, the hydraulic pressure switching lever is activated via the actuating plate 19, the connecting rod 20, and the valve arm 21 as shown in FIG. When the central float 22 moves downward significantly, the state is changed to the state shown in FIG. 15.

Reference numeral 27 denotes an operating lever guide rod, which is fixed near the hand side of the operating handle 6, and has regulating grooves 27 for the three operating levers shown in FIG.
a, 27b, and 27c are drilled in the regulating groove 27a, and a driving clutch operating lever 28 is provided in the regulating groove 27a.
A planting clutch operating lever 29 is fitted in b, and a hydraulic switching lever 30 is fitted in the regulating groove 27c. Each of the levers 28, 29, 30 is rotatably pivoted on a horizontal shaft 31 fixed to the guide frame 27, and is rotatable in the front-back direction. is the operation wire 28
U-shaped bent metal fittings 28b, 29b, and 30b for attaching a, 29a, and 30a are pivotally attached, and the pivot points of the metal fittings attached to the levers are aligned with the horizontal axis 31 in the direction in which each wire is pulled. A so-called fulcrum crossing mechanism is constructed in which the wire is fixed in a pulled state when crossing.

To explain the power transmission mechanism from the prime mover 1 to the traveling transmission part, the hydraulic pressure is transmitted from the prime mover side pulley 32 to the hydraulic pump case 33 (in which the hydraulic pump 17 is installed) which is integrally attached to the front side of the traveling transmission case 3. Two-stage pulley 3 fixed to the drive shaft 34
The power is transmitted to the pulleys 6 and 37 via the V-belt 35, and the power is transmitted from the pulley 37 to the input pulley 38 of the traveling transmission case 3 part via the V-belt 39.

Then, the V-belt 39 is wrapped loosely,
A tension clutch pulley 40 for switching the V-belt 39 between a tensioned state and a relaxed state is provided via an arm 41, thereby forming a running clutch.

42 is a rotation boss of the arm 41, and 43 is a coil spring that constantly acts in the direction in which the tension clutch pulley 40 relaxes the V-belt 39. and,
The rotation boss 42 of the arm 41 is connected to a link mechanism 44
It is connected to the operating wire 28a via.

The operating wire 29a is connected to an arm 45 that is connected to a clutch shifter that turns on and off power to the planting section in the planting mission case 5.

Further, the operating wire 30a connected to the hydraulic switching lever 30 has a slidable pin 47 loosely fitted in a support fitting 46 fixed to its tip, and furthermore, this pin 47 is always extended in the protruding direction via a flange 48. The tip of this pin is connected to the actuating plate 19 by fitting into the elongated hole 49. Then, when the operating wire 30a is loosened and the pin 47 is pushed by the spring 48 to the protruding state using the hydraulic switching lever 30, the relative position of the pin 47 and the elongated hole 49 is changed from the solid line state shown in FIG. 8 to the elongated hole. The front end B of 49 is pushed by the pin 47, and the actuating plate 19 is in the dotted line state, and the hydraulic switching valve 18 is activated via the connecting rod 20 and the valve arm 21.
9 is also switched from the solid line state to the dotted line state in FIG.
The rear end C of 9 is pulled by the pin 47, and the actuating plate 19 is in the state shown by the dotted line in FIG.
is also switched to the state shown by the dotted line in FIG. Furthermore, with the operating wire 30a in a slightly tensioned state, the pin 4
7 is set in the middle of the elongated hole 49 so that the operating plate 19 can be rotated by approximately the same amount forward and backward, the hydraulic switching valve 18 changes from the dotted line state shown in FIG. 11 to the solid line state. It is configured so that it can be freely moved up to the point where it can move freely.

It is also possible to hold the hydraulic pressure switching valve 18 in the solid line state shown in FIG. 9 by pulling the operating wire 30a a little strongly and pulling the rear end C of the elongated hole 49 with a pin.

The switching state of the above hydraulic switching valve is shown in FIGS. 7 and 13 to 1 from the relative position of the hydraulic switching lever 30.
To explain based on Fig. 5, the operation lever guide frame 2
If the lever 30 is operated to point a in the regulation groove 27C of No. 7, the wire 30a becomes slack, the hydraulic pressure switching valve 18 is switched to the state shown in FIG. 15, and the lever 30
When set to point b, the hydraulic switching valve 18 is set to the 13th point.
The lever 30 is in a free state that can be freely switched to any of the states shown in Fig. 14 and Fig. 15.
is set at point c, the rear end C of the long hole 49 of the actuation plate 19 is in contact with the pin 47,
The connection is set as shown in the figure, and when the lever 30 is set at point d, the wire 30a is pulled to the maximum and fixed in the state shown in FIG. 13.

Reference numeral 50 denotes an interlocking plate, which is fixed to a pipe 52 that is inserted into a shaft 51 provided in the operating lever guide frame 27 in parallel with the horizontal shaft 31, and this pipe 52 and the operating lever 28 for the travel clutch are connected by a rod. 53, and the rotating end side of the interlocking plate 50 is provided facing the direction in which the wire 30a of the hydraulic pressure switching lever 30 is operated to loosen it, and the traveling clutch operation lever 28 is connected to the clutch "on" position. When operated to the side, the interlocking plate 50 operates in the state shown in FIGS.
7c, it is forcibly moved to point b, and conversely, when the hydraulic switching lever 30 is located at point b, the traveling clutch operating lever 28 is turned off. When the hydraulic switching lever 30 is operated from the side, the pin 47 is moved to point a by the spring 48 which urges the pin 47 in the projecting direction, and when the hydraulic switching lever 30 is operated from the side, the hydraulic switching lever 30 is moved from point b to point a.
Operating lever 2 for the travel clutch when operating the
8 is configured to be interlocked with the clutch from "on" to "off".

Further, in order to operate the interlocking plate 50, the operating lever 28 for the traveling clutch and the pipe 52 are connected by the rod 53, but the operating lever 29 for the planting clutch and the pipe 52 are similarly connected by the rod 53. Alternatively, the rods 53 may be provided separately and connected to both operating levers 28 and 29, respectively.

Figures 16 and 17 show the present invention being applied to a riding type rice transplanter, in which case the seedling planting device frame A is equipped with a seedling tank 8 that reciprocates from side to side and a planting device 9. The four-point link 54 and the seedling planting device frame A are attached to the traveling machine frame B via a rolling mechanism 55 that is rotatable horizontally, vertically, and vertically.

The traveling machine frame B is a so-called tractor that includes a prime mover (not shown), a steering wheel 58, and a passenger seat 63 on a chassis having front wheels 56 for steering and rear wheels 57 for driving. In the illustrated example, a rear wheel 57 is supported on the rear end of a chain case 10a that extends from both left and right sides of the traveling transmission case 3a toward the rear lower part, and is attached to the left and right chain case 10a via a horizontal frame 59. A fulcrum on the starting end side of the four-point link mechanism 54 is provided and attached to the protruding metal fitting 60.

Reference numerals 22a and 23a denote a central float and side floats, respectively, which are mounted on the seedling transplanting device frame A so that the front part can move up and down with the rear part as a fulcrum.

The hydraulic switching valve 18 is fixed to a support rod 61 projecting from the front end of the seedling planting device frame A, and is configured to be switched by the vertical movement of the central float 22a. .

16a is a hydraulic cylinder, 12a is a piston, the base of this hydraulic cylinder 16a is pivotally connected to the traveling transmission case 3, and the piston 12a is
The tip of the four-point link mechanism 54 is connected to an arm 62 that is integrally provided with the upper link rod of the four-point link mechanism 54.

Then, when the central float 22a moves up and gets too close to the seedling transplanting device A, the hydraulic switching valve 18 switches as shown in FIG. 13 to project the piston 12a and raise the seedling transplanting device frame A. On the other hand, if the center float 22a moves downward and becomes too far apart, valve 1
8 is switched as shown in Fig. 15, and the seedling planting device machine frame A
Automatic control is provided so that the lowering speed is lowered.

27a is an operating lever guide frame, which is provided on the side of the passenger seat 63 and has the same configuration as the above-mentioned walk-behind rice transplanter;
8, a planting clutch operation lever 29 and a hydraulic switching lever 30 are provided.

Note that the interlocking and relative positions of the operating levers 28, 29, 30 and the hydraulic switching valve 18 are the same as in the case of the walk-behind rice transplanter, and therefore will not be described again.

Next, to explain the operation of the above example, seedlings are placed in the seedling tank 8, each rotating part is driven by the prime mover 1, and the driving clutch operating lever 28 and the planting clutch operating lever 29 are turned into the clutch. '' (direction of arrow D), the interlocking plate 50 is rotated and set in the direction of arrow H via the rod 53 and pipe 52. At this time, if the hydraulic pressure switching lever 30 is set at point a in FIG. 7 as shown in FIG. 6, that is, the hydraulic pressure switching valve is switched to the state shown in FIG. 15 and the walking rice transplanter is used. When the piston 12 is retracted into the hydraulic cylinder 16 under the weight of the aircraft and the traveling wheels 11 move upward, and the automatic control by hydraulic pressure is not effective, the interlocking plate 50 switches the hydraulic pressure switching lever 30 to the position shown in FIG. Return to point b (state in Figure 5).

Furthermore, when the hydraulic switching lever 30 is located at point d in FIG. 7, the hydraulic switching valve 18 is in the state shown in FIG. Since the machine frame A and the center float 22 are floating high above the field, it can be recognized at a glance that planting is not possible, so operate the lever 30 to return it to point b in Fig. 7. do.

The same applies to a riding rice transplanter, and when the hydraulic switching lever 30 is in the state shown in FIG. , central float 2 in the field
2a, when the side float 23a is crimped under the full load of the seedling planting device machine frame A and automatic control is not available, the traveling clutch operating lever 28 or the planting clutch operating lever 29 is turned to the clutch "on" position. By changing to the state shown in FIG. 5 on the side, it is possible to return to a state where automatic control is effective.

When the hydraulic switching lever 30 is located at point d in FIG. 7 and the hydraulic switching valve 18 is in the state shown in FIG. 3, the piston 12a protrudes from the hydraulic cylinder 16a, so the four-point link 54 Since the seedling transplanting device frame A is lifted upward through the , it can be recognized at first glance that planting is not possible, as in the case of the walking-type rice transplanter described above, and therefore,
Return the hydraulic switching lever 30 to point b.

As mentioned above, regardless of whether the rice transplanter is a walking type or a riding type, when seedling planting work is started with the hydraulic switching lever 30 positioned at point b in Fig. 7, in the case of a walking type rice transplanter, The running wheels 11 come into contact with the tiller surface, and the center float 22 and side floats 23 are moved forward in contact with the surface of the topsoil, while the seedling tank 8 reciprocates from side to side and feeds the seedlings from the seedling supply port provided at the lower part of the front end. put out. At this time, the planting device 9 moves up and down to engage the sent out seedlings one by one and insert them into the leveled topsoil surface using the lower float.
Seedlings are planted one after another in this way, but in the case of a walk-behind rice transplanter, when the tiller surface becomes deeper and the running wheels 11 begin to rise above the tiller surface, the ground pressure of the floats 22 and 23 increases. The center and side floats 22 and 23 are moved upward by the surface of the topsoil. Then, the actuating plate 19 is pushed up by the connecting rod 26 and rotated around the pivot point A.

At this time, since the hydraulic pressure switching lever 30 is at point b in the regulation groove 27c of the operating lever guide frame 27, the pin 47 connected by the operating wire 30a
is located between the left and right sides of the elongated hole 49 bored in the actuating plate 19, so that the actuating plate 19 can freely rotate and operate the hydraulic switching valve 18 via the connecting rod 20 and the valve arm 21. The state will be changed to the state shown in Fig. 13. Therefore, oil discharged from the hydraulic pump 17 is sent into the hydraulic cylinder 16, and the piston 12 protrudes. Then, the running wheel 11 is moved down via the balance rod 13, rod 14, arm 15, and chain case 10, gradually coming into strong contact with the tilling plate surface, and lifting the seedling planting device frame A. Then, when the floats 22 and 23 are reversibly lowered and a proper planting state is reached, the hydraulic switching valve 18 is operated in the opposite manner to the above, and the neutral state shown in FIG. Maintain a neutral position without being sent.

Next, when the tillage surface changes shallowly, the seedling planting device machine frame A is positioned higher than the topsoil surface, contrary to the above, so the front parts of the center and side floats 22 and 23 hang downward. As a result, the distance between the seedling planting device and the machine frame A is too large, so the connecting rod 26 is pulled down by the central float 22. Therefore, the operating plate 19 rotates to switch the hydraulic switching valve 18 to the state shown in FIG. 15.

Then, the oil in the hydraulic cylinder 16 is in a state where it can return to the traveling transmission case which also serves as a hydraulic tank, and the slow piston 12 is pushed in by the load of the seedling planting device machine frame A, causing the traveling wheels 11 to move upward. On the other hand, as the seedling planting device frame A is lowered and a proper seedling planting condition is achieved, the hydraulic pressure switching valve is restored to the state shown in FIG. 14.

In this way, automatic control is activated by variations in the depth of the tiller surface, and the planting operation is always carried out in a proper state for planting seedlings.

During the work, if the number of seedlings in the seedling tank 8 decreases and needs to be replenished, rotate both the driving clutch operating lever 28 and the planting clutch operating lever 29 in the direction opposite to the direction of the arrow D to reach the fulcrum. Remove the overstepping state,
When the operating wires 28a and 29a are loosened, both clutches connected thereto are turned off, and the seedling planting operation is stopped. At this time, the interlocking plate 50, which is interlocked with the travel clutch operating lever 28 by the rod 53 and the pipe 52, is switched to a state far away from the hydraulic pressure switching lever 30, as shown in FIG. Move the hydraulic switching lever 30 to a in Fig. 7.
It can be operated to the dot part (Fig. 6). Then, the operating wire 30a is sufficiently loosened and protrudes from the pin 47 under the elastic force of the spring 48, operating the operating plate 19 to the state shown by the dotted line in FIG. Then, switch the hydraulic pressure switching valve 18 to the state shown in FIG.

Therefore, the oil from the hydraulic pump 17 is directly sent into the traveling mission case 3, and the oil in the hydraulic cylinder 16 is also returned to the mission case 3. Therefore, the traveling wheels 11 are moved upward under the load of the seedling planting device machine frame A, and the entire machine body is lowered and maintained in a safe state where hydraulic control does not work. Therefore, seedlings can be replenished very easily.

In addition, when replenishing seedlings, the hydraulic switching lever 30 can be set to the seventh position without having to operate the driving clutch operating lever 28 and the planting clutch operating lever 29 and turning each clutch to "off" as described above. If you push strongly from point b to point a in the diagram, you will get
It is also possible to turn off the traveling clutch, the planting clutch, or both from the interlocking plate 50 side via the pipe 52 and rod 53.

After the seedlings have been supplied to the seedling tank 8 in this way, the driving clutch operating lever 28 and the planting clutch operating lever 29 are turned on, and the rod 53 and the pipe 52 are turned on. The interlocking plate 50 is rotated in the direction of arrow H through
position and thus automatically returned to the automatically controlled state.

Therefore, the seedling replenishment work is extremely easy, and if the hydraulic switching lever 30 is left at the seedling replenishment position at point a in FIG. If you plant in the correct condition, unexpected situations will not occur.

Next, when reaching near the ridge and turning back to plant, or when going over the ridge, turn the planting clutch to "off" and then turn the hydraulic switching lever 30 to the 7th position.
When the operation is performed to point d in the figure to cross over the fulcrum, the pin 47 is attracted against the spring 48 by the operation wire 30a, the actuating plate 19 is rotated to the dotted line state in FIG. It is switched to the state shown in Figure 13. Therefore, oil is sent into the hydraulic cylinder 16 and the piston 12 is protruded to the maximum extent. At this time, a check valve 64 provided at the base of the piston is opened by a pin 65 pushed by the end wall of the cylinder, and the oil travels through an oil return path 66 provided at the end of the cylinder 16 to the mission case. Returned to 3.

Therefore, since the running wheels 11 are lowered to the maximum extent and maintained in that state, the rice transplanter can easily turn or go over ridges.

Next, when driving on the road, operate the hydraulic pressure switching lever 30 to appropriately raise or lower the driving wheels 11, and then set the height to the optimum height for driving on the road, and then move to the position of point C in Fig. 7. Once set, the hydraulic switching valve 18 is switched to the state shown in FIG. 14. Then, the actuating plate 19 attempts to rotate around the pivot point A due to the gravity of the central float 22, but the pin 4
7 prevents this rotation, and the hydraulic switching valve 18 is maintained in the state shown in FIG.

Therefore, the height of the seedling planting device frame A is set to suit the height of the driver, making it easier to drive on the road.

Next, to briefly explain the case of a riding type rice transplanter, when replenishing seedlings to the seedling tank 8, operate the travel clutch operating lever 28 and the planting clutch operating lever 29 to turn both clutches off. After that,
When the hydraulic pressure switching lever 30 is rotated to point a in FIG. 7, the hydraulic pressure switching valve 18 is switched to the state shown in FIG. 15. Therefore, when the planting operation frame A is lifted, it is lowered, or when it is in the planting state, it remains as it is, and the central float 22a is pushed upward to bring the planting device frame A into a stable state. Retained. When the seedling supply is finished in this stable state where automatic control is not possible, the drive clutch operation lever 28
When the planting clutch operation lever 29 is operated to put the clutch in the "on" state, the interlocking plate 50 is switched from the state shown in FIG. 6 to the state shown in FIG. 30 is rotated to point b in FIG.

Therefore, as soon as the seedling planting work is started, automatic control becomes effective.

That is, when the front wheels 56 and rear wheels 57 on the traveling device frame B side sink deeply from the topsoil surface, the central float 22a and side floats 23a on the planting device frame A side are strongly pressed against the topsoil surface, and their tips move upward. do. Therefore, the hydraulic switching valve 18 is switched to the state shown in FIG. 13 in the same manner as in the case of a walk-behind rice transplanter, the piston 12a is protruded, and the planting device frame A is lifted up via the four-point link 54. When it is lifted to a proper state, the hydraulic switching valve 18 is switched to the neutral state shown in FIG. 14 by the downward movement of the central float 22a.

On the other hand, if the tilling surface is shallow and the planting device frame A side tends to float up, making it inappropriate for planting seedlings, the hydraulic switching valve 18 is activated via the central float 22a.
is switched to the state shown in FIG. 15, and the hydraulic piston 1
2a receives the load and retracts, and the planting device frame A moves downward and restores to its proper state. In this way, always
Automatically controlled conditions suitable for planting seedlings.

In addition, in the case of a riding rice transplanter, the hydraulic switching lever 3
0 to position d in FIG. 7, the hydraulic switching valve switches to the state shown in FIG. 13, and the planting device frame A is lifted to the maximum extent. Furthermore, by setting the hydraulic pressure switching lever 30 to point C in FIG. 7, the planting device frame A can be lifted and set to any desired height.

As described above, since this invention has the above-described configuration, when replenishing seedlings to the seedling tank, after operating the hydraulic pressure switching lever and replenishing the seedlings in a stable state where hydraulic control is not possible, it is possible to return the seedlings to the original tank. Even if you do not have to separately return the hydraulic control to the operating state, the automatic control will automatically switch to the operating state when the traveling or planting clutch is turned on again, and the seedlings will be seeded without the automatic control operating. This eliminates the need for unforeseen situations that would cause the planting work to continue, and in addition, when the clutch is turned off, there is no need for strong force such as manually pushing the float, and the spring Since the upward force of the float can be suppressed smoothly by force, the operation is easy, and the effect of mitigating the impact on the switching valve side is achieved.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which Fig. 1 is a side view of the embodiment in a walk-behind rice transplanter, Fig. 2 is a plan view of its main parts, and Fig. 3 is a side view thereof.
Figure 4 is a perspective view of the main part, Figures 5 and 6 are side sectional views of the main part, Figure 7 is a plan view of the main part, and Figures 8 and 10 show the operating state of the main part. 9 and 11 are switching operation diagrams of the hydraulic switching valve in the case of FIGS. 8 and 10. FIG. 12 is a side view of the main part with a part of the hydraulic device sectioned, and FIG. 15 to 15 are operational views of the hydraulic switching valve, FIG. 16 is a side view of an embodiment of the riding rice transplanter, and FIG. 17 is a plan view thereof. Symbols in the figure: A is the seedling planting device machine frame, B is the traveling machine frame, 8 is the seedling tank, 9 is the planting device, 11, 56,
57 is a running wheel, 22, 22a is a float, 18
28 is a driving clutch operating lever, 29 is a planting clutch operating lever, and 30 is a hydraulic switching lever.

Claims (1)

[Claims] 1. A seedling planting device machine frame A that is equipped with a planting device 9 that divides and plants seedlings from a seedling tank 8, and a traveling machine frame B that is equipped with running wheels 11 that touch the plowing surface of the field and drive the vehicle body for traction. Furthermore, a float 22 that floats and slides on the surface of the topsoil of the field is provided, and the relationship between the seedling planting device machine frame A, the traveling machine frame B, and the float 22 is established through a hydraulic system. When the float 22 rises to A and gets too close to the predetermined proper seedling planting range, this excessive approach is prevented, and conversely, when it descends from the proper seedling planting range and moves too far away, this excessive approach is prevented. In a rice transplanter equipped with a hydraulic control device that is linked to prevent separation, a long hole 49 is bored in a rotatable operating plate 19 that is connected to a switching valve 18 of the hydraulic device and operates the switching valve 18. A pin 47 is provided that fits into the elongated hole 49 and can be operated between a state in which the actuating plate 19 is free to move and a state in which one side of the rotation direction is restricted and the movement is blocked, and this pin 47 is used to operate the rice transplanter. The pin 47 is connected to a hydraulic switching lever 30 provided near the position, and a spring 48 is used to constantly energize the pin 47. An automatic control state in which A automatically controls the elevation, a rising state in which the pin 47 is operated to the tension side to rise and stop, and a descending state in which the pin 47 is rotated by a spring 48 to descend and stop. The hydraulic switching lever system and the clutch lever system for running the rice transplanter or planting the rice transplanter are provided so as to be switchable between three position setting states. The oil pressure switching valve 18 prevents the seedling planting device frame A from being set in the lowered state when the power is turned off, and the tension of the spring 48 causes the hydraulic switching valve 18 to be set in the lowered state when the power is "off". An operating device for a rice transplanter characterized by the following.