JPS6314588Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a device that lifts and lowers a rice transplanter by moving up and down the wheels that support it.
Specifically, when automatically controlling the height of the machine relative to the field during rice planting work to a substantially constant value, there is a negative impact on the automatic control of the height of the machine by adjusting the seedling planting depth by moving the rear part of the float up and down. By reducing this, automatic control of the height of the machine body can be performed accurately and under the same conditions for any seedling planting depth.

Next, an explanation will be given of an embodiment drawing in which an example of the present invention is applied to a two-row rice transplanter.
is equipped with a fuselage 6 which is directly connected to a transmission case 5 via a cylindrical case 4 at the rear thereof, a float 7 that slides on a field surface 87 on the lower surface of the fuselage 6, and a pair of left and right wheels 8, 8. 1 shows a traveling type rice transplanter that travels in the direction of arrow A, and the transmission case 5 is equipped with a seedling planting device 11 consisting of a pair of left and right swinging seedling planting mechanisms 9 and a backward-tilting seedling platform 10. The rear upper end of the transmission case 5 is provided with a pair of left and right control handles 12 that extend along the back surface of the seedling stand 10 and substantially parallel thereto, and the rear end of the float 7 is connected to the transmission case 5 or other body. The front end of the float 7 is pivoted to the lower end of the seedling depth adjustment rod 13, which is attached so as to be vertically movable, with a pin 13a so that the front part of the float 7 can freely rotate in the vertical direction. is configured to be movable up and down with a doglegged link mechanism 17 consisting of an upper link 15 and a lower link 16 with respect to a bracket 14 attached to the lower surface of the engine 3, and a float 7 is attached to the bracket 14 on the lower surface of the engine 3. An upper limit stopper 18 is provided which comes into contact with the fuselage when the float is closest to the fuselage to define the maximum raised position of the float 7 with respect to the fuselage.
When the float 7 is maximally separated from the fuselage, the lower link 16 comes into contact with the bracket 19 to which the lower link 16 of the float 7 is pivotally attached to the float 7, thereby preventing the doglegged link mechanism 17 from extending beyond a certain level. Accordingly, a lower limit stopper pin 20 is provided to restrict the maximum lowering position of the float 7 relative to the aircraft body, and the upper limit stopper 18 and the lower limit stopper pin 20 are configured to restrict the vertical movement of the float 7 within a certain range h. (Figure 8).

The two wheels 8, 8 are respectively attached to the tips of swing cases 21, 21 whose bases are rotatably mounted on the left and right side surfaces of the transmission case 2, and are powered by the engine 3 to drive the transmission mechanism ( (not shown) and a chain (not shown) in the swing case 21, etc., and a hydraulic pump 22 driven by the engine 3 is provided at an appropriate location of the transmission case 2. A single-acting hydraulic cylinder 23 is mounted on the upper surface of the transmission case 2.
However, the piston 24 is provided so as to protrude rearward along the center line of the rice transplanter 1, and a buffer spring 25 is attached to the tip of the piston 24 in the direction of the protrusion movement of the piston 24. The held slider 26 is slidably fitted, and the center portions of a pair of upper and lower swinging rods 27, 27 are pivoted to pins 28, 28 so as to be horizontally rotatable. .

Lifting arms 29, 29 are attached to the left and right sides of the cylindrical frame 4 of the fuselage 6.
The rods 31, 31 are rotatably fitted onto a shaft 30 which is supported through the shaft perpendicularly to the vertical axis.
A lever 3 is provided integrally with both lifting arms 29, 29 on the shaft 30, and is connected to each other via a lever 3.
The tips of 2 and 32 and both ends of the swinging rods 27 and 27 are respectively connected via connecting rods 33 and 33 so that both wheels 8 and 8 are moved up and down in opposite directions,
The structure is such that both wheels 8, 8 move up and down simultaneously by the operation of the hydraulic cylinder 23, thereby raising and lowering the body.

Reference numeral 34 indicates a rotary type 3-port 3-position hydraulic switching valve provided at an appropriate location in the transmission case 2, and a circuit 3 is connected to the pump port P of the switching valve 34.
5, the port A is connected to the inlet port 37 of the hydraulic cylinder 23 via the circuit 36, the return port R is connected to the oil tank 39 via the circuit 38, and the switching valve 34 is connected to the hydraulic pump 22 via the switch valve 34. When the rotating spool 40 is in the neutral position, port A is closed and ports P and R are communicated through the through hole 41 to stop the vertical movement of the aircraft.If the rotating spool 40 rotates counterclockwise from the neutral position, port P is closed. is closed, ports A and R communicate through the throttled through hole 42, and the aircraft is lowered.
When the rotary spool 40 rotates clockwise from the neutral position, the port R is closed and the ports P and A are communicated through the through hole 43, so that the body is raised. In this case, the minimum lowered position of the aircraft is such that the end of the piston 24 in the hydraulic cylinder 23 is at the bottom plate 4 of the hydraulic cylinder 23.
4, while the highest position of the aircraft is controlled by the pin 4 provided at the end of the piston 24.
5 comes into contact with the inside of the lid 46 of the hydraulic cylinder 23, and at this maximum raised position, the L-shaped passage 47 at the end of the piston 24 matches the relief port 48 of the lid 46, and the hydraulic cylinder The hydraulic pressure continuously sent into the pump 23 escapes to the oil tank 39 via a relief port 48 and a circuit 49 to maintain the maximum raised position.

In FIG. 3, reference numerals 50 and 51 indicate relief valves, and the slider 26 at the tip of the piston 24 of the hydraulic cylinder 23 is integrally equipped with a fan-shaped plate 52 located between the pair of swinging rods 27 and 27. The fan-shaped plate 52 is provided with a pivot pin 28 of the swinging rod 27.
A plurality of pin holes 53 are drilled on an arc centered at and a spring 57 that is operated remotely via the bell handle lever 55.
A pin 56 is provided, and the pin 56 is attached to the fan-shaped plate 5.
By fitting the swinging rod 27 into any pin hole 53 in the wheel 2, the swinging rod 27 is locked so that both wheels 8, 8 cannot swing in any reverse operation position.

Reference numeral 58 denotes a sensor which is movable up and down with a proximal end boss 60 which is rotatably fitted loosely into a shaft 59 attached to the lower surface of the mission case 2, etc. The sensor 58 has a trochanter 61 at its tip The float 7 is brought into contact with the front upper surface of the float 7 at a position close to both the upper limit stopper 18 and the lower limit stopper pin 20 of the float 7, and is biased against the float 7 by a spring 62 at the proximal end. The base end shaft 59 is configured to move up and down in conjunction with the up and down movement of the control link 63.
is rotatably fitted, and a lever 65 attached to the tip of the control link 63 and the rotating spool 40 of the switching valve 34 is controlled so that when the control link 63 is in the position shown in the figure, the switching valve 34 is in the neutral position. The switching valve 34 is connected via a rod 66 with a turnbuckle 66' so that when the link 63 is rotated to the left, the switching valve 34 is lowered, and when the control link 63 is rotated to the right, the switching valve 34 is raised. The proximal end boss 64 of the control link 63 and the proximal end boss 60 of the sensor 58 are engaged with each other by clutch pawls 67 and 68 having a play of an appropriate rotational angle θ, while both these proximal end bosses 60 and 64
The torsion spring 69 fitted in the control link 63
When the sensor 58 rotates downward in conjunction with the float 7, the control link 63 rotates to the left due to the engagement of the clutch pawls 68 and 67, and the sensor 58 rotates upward. When it rotates, the control link 6
3 is configured to rotate clockwise. That is, when the sensor 58, which is in contact with the upper surface of the float 7 via the trochanter 61, is in the normal position N as shown by the solid line in FIG. 8, the switching valve 34 is in the neutral position;
When the sensor 58 moves from the N position to the upper U position, the switching valve 34 switches to lower the aircraft, and when the sensor 58 moves from the N position to the lower D position, the switching valve 34 switches to raise the aircraft. has been done.

Further, a regulating piece 70 is provided on the base end boss 64 of the control link 63, and the regulating piece 70 is attached to the base end boss 64 of the control link 63.
When the switching valve 34 is rotated to the aircraft lowering position, the adjustment screw stopper 72 attached to the lower surface of the case 2 via the bracket 71 is contacted, so that the switching valve 34 is connected to the return port R when the aircraft is lowered. The opening area of the spool 40 through hole 42 is regulated to a constant value, and the regulated opening area is adjustable.
A circular arc-shaped long groove hole 73 centered at 9 is bored,
A pin 74 is slidably inserted into this.

Reference numeral 75 denotes a manual lift lever which is pivoted to a pin 76 to be able to move up and down at an appropriate location on the operating handle 12, etc., and the manual lift lever 75 rotates along a guide groove 78 in a guide plate 77. The tip of the wire 80, which is configured to On the other hand, pin 74
is pulled in the opposite direction to the wire 80 by a spring 84 whose one end is locked to a pin 83 of the transmission case 2, and the manual lift lever 75 is moved to the automatic position at a step 85 in the middle of the guide groove 78. Ba,
The pin 74 is in the position shown in the figure, but the manual lift lever 7
5 is rotated downward from the automatic position along the guide groove 78 and fitted into the horizontal groove 86, the pin 74 moves significantly to the right due to the tension of the wire 80, and the control link 63 rotates clockwise in priority to the sensor 58. Then, the manual lift lever 75 is rotated upward from the automatic position to raise the upper end 8 of the guide groove 78.
7, the force of the spring 84 causes the pin 74 to move largely to the left, causing the control ring 63 to rotate to the left in preference to the sensor 58, thereby lowering the aircraft.

In this configuration, when the manual lift lever 75 is in the automatic position, the control link 63 that is linked to the switching valve 34 is linked to the sensor 58 to move the pin 74 within the length range of the slotted hole 73 into which the pin 74 is fitted. However, since the pin 74 that fits into the long slot hole 73 is related to the manual lift lever 75, when the manual lift lever 75 is placed in the lowered position, it will not engage with the pin 74 of the control link 63. Arrived spring 8
The switching valve 34 is switched to lower the aircraft by the four forces,
The oil pressure in the hydraulic cylinder 23 is returned to the oil tank 39, and the piston 24 moves backward due to the weight of the aircraft.
Since both swing cases 21, 21 rotate upward simultaneously, the aircraft moves downward, and when the manual lifting lever 75 is moved from the automatic position to the aircraft lifting position against the force of the spring 84, the tension of the wire 80 As a result, the switching valve 34 is switched to raise the aircraft, the hydraulic pressure from the hydraulic pump 22 is sent to the hydraulic cylinder 23, the piston 24 moves forward, and both swing cases 21, 21 simultaneously rotate downward, so that the aircraft is raised. If the manual lift lever 75 is fitted into the horizontal groove 86 and locked in this raised position, the pin 45 provided on the piston 24 will move upward when the piston 24 reaches its maximum stroke. 4
6 and the forward movement stops, the L-shaped passage 47 coincides with the relief port 48 and the hydraulic pressure escapes, so the upward movement of the aircraft automatically stops at the maximum upward position, and at that position. Retained. Also,
When the manual elevating lever 75 is placed in the body lowering position, the end of the piston 24 moves backward until it comes into contact with the bottom plate 44 of the hydraulic cylinder 23, and the downward movement of the body automatically stops at the minimum lowering position.

Next, in order to perform rice planting work in the field, first move the manual lift lever 75 into the field with the machine in the raised position, and then move the manual lift lever 75 into the guide groove 7.
The automatic position is set at the step 85 in the middle, but by moving the manual lift lever 75 from the aircraft raised position to the automatic position, the pin 74 that fits into the long groove hole 73 of the control link 63 returns to its original position, and the control Since the rightward tension on the link 63 is released, the control link 63 is rotated to the left by the downward rotation of the sensor 58 toward the float 7, which is away from the fuselage, until the doglegged link mechanism 17 is fully extended. Then, the switching valve 34 is switched to raise the aircraft, so the aircraft begins to descend, the float 7 touches down on the field 87, and the distance between the float 7 and the aircraft gradually approaches until the distance reaches a predetermined height. When the sensor 58 rotates upward, the switching valve 34 is activated via the control link 63.
is returned to the neutral position, the descent of the machine body stops, and the height of the machine body relative to the field scene 87 can be automatically set to a predetermined height. By driving 11, rice transplanting work is performed.

During this rice planting work, if the height of the machine relative to the field changes due to unevenness of the tiller 88 where the wheels 8 touch the ground and the field scene 87 where the float 7 touches the ground, pressure is applied to the float 7. The contacting sensor 58 is rotated downward, and when the downward rotation reaches the D position, the switching valve 34 is switched to lower the machine body, and the machine body is returned to a predetermined height position, and the machine body is returned to the predetermined height position. When the height relative to the surface changes to become lower, the sensor 58 rotates upward, and when the upward rotation reaches the U position, the switching valve 34 switches to raise the aircraft. is returned to a predetermined height position, and so on.
The height of the machine with respect to the field scene 87 is automatically controlled and adjusted to a predetermined height position, and even during this automatic control adjustment operation, the machine is controlled by the sensor 58 by rotating the manual lift lever 75. figure,
In other words, it is possible to ascend and descend with priority over automatic control, and by giving priority to what is at hand, it is possible to make directional turns extremely easily at the edge of the shore.

Then, the seedling planting depth adjustment rod 13 connecting between the rear end of the float 7 and the transmission case 5 is rotated upward to move the pivot pin 13a of the float 7 to the lower position 1.
By shifting to 3a', the distance between the end of the float 7 and the body becomes higher, so the planting depth of the seedlings becomes shallower, and by rotating the seedling planting depth adjustment rod 13 downward, the height of the float 7 is increased. By displacing the pivot pin 13a to the upper position 13a'', the distance between the rear part of the float 7 and the body becomes lower, so that the seedling planting depth becomes deeper, and by rotating the seedling planting depth adjustment rod 13. The planting depth of the seedlings can be adjusted arbitrarily, and the maximum lifting position of the float 7 relative to the aircraft body is set by the upper limit stopper 18 located at the front, and the maximum lowering position of the float 7 relative to the aircraft body is set by the lower limit located at the front. They are each defined by a stopper pin 20.

In this way, by defining the maximum lowering position of the float 7 with the lower limit lower limit stopper pin 20 located at the front, when the rice transplanter raises the rice transplanter greatly during a direction turn at the edge of a ridge, etc., the float 7
can be lifted away from the field at the same time, and by setting the maximum lifting position of the float 7 with the upper limit stopper 18 located at the front, it is possible to suppress excessive upward movement of the float 7 during rice planting work. It is.

However, as mentioned above, the vertical movement of the float 7 is
With the upper limit stopper 18 and lower limit stopper pin 20 at the front position in the specified state, the seedling planting depth adjustment rod 1 is
When the seedling planting depth is adjusted by the rotation operation in step 3, there is a distance between the position of the sensor 58 relative to the float 7 and the positions of the upper limit stopper 18 and the lower limit stopper pin 20 as follows. 14
15 and 16 (however, in these figures, the symbol B indicates the relationship between the float 7 and the upper limit stopper 18 when the float pivot pin 13a is set to the standard seedling planting depth. Symbol C indicates the upper limit line of the state when the seedling is hit, and symbol C indicates the lower limit line of the state where the downward movement of the float 7 is regulated by the lower limit stopper pin 20 when the float pivot pin 13a is set to the standard seedling planting depth. In addition, symbol B' indicates the upper limit line of the float 7 when the float pivot pin 13a is set at a shallow seedling planting depth at the lower position 13a', and symbol C' indicates the upper limit line of the float 7 when the float pivot pin 13a is set at the lower position 13a'. The lower limit line of the float 7 is shown when the seedling planting depth is shallow at 13a'. Furthermore, the symbol B'' indicates the lower limit line of the float 7 when the float pivot pin 13a is set at the upper position 13a'' at the deep seedling planting depth. (C'' indicates the upper limit line of the float 7, and C'' indicates the lower limit line of the float 7 when the float pivot pin 13a is set at the deep seedling planting depth of the upper position 13a'').

That is, if the relative position of the sensor 58 with respect to the float 7 is set to a position farther away from the upper limit stopper 18 and the lower limit stopper pin 20 toward the float pivot pin 13a as shown in FIG. The position U when the switching valve 34 is switched to raise the fuselage via the sensor 58 is the lower position 1 when the float pivot pin 13a is
When the shallow seedling planting depth of 3a' approaches the upper limit line B' of the float 7, the switching valve 3
4, the stroke for switching to the aircraft up position is lost or the margin for that stroke is reduced, while the position D when the switching valve 34 is switched to the aircraft lowering state via the sensor 58 due to the lowering of the float 7 is , move the float pivot pin 13a to the upper position 13
Float 7 when planting seedlings at a deep depth of a″
When approaching the lower limit line C'', the switching valve 34
As a result, the stroke for switching to forward raising is lost or the margin for that stroke is reduced, making the switching operation of the switching valve 34 in both positions impossible or incomplete, resulting in the aircraft's raising motion and There is a problem that the height control of the aircraft is not stabilized because the lowering movement becomes impossible and the speed of the raising and lowering movements becomes slow.

Furthermore, if the upper limit stopper 18 and the lower limit stopper pin 20 are set to a position farther away from the relative position of the sensor 58 to the float 7 toward the float pivot pin 13a as shown in FIG. Due to the rise of the switching valve 34
The position U when the switch to raise the body via the sensor 58 approaches the upper limit line B'' of the float 7 when the float pivot pin 13a is set at the deep seedling planting depth of the upper position 13a''. , the stroke for switching the switching valve 34 to raise the aircraft body is lost or the margin for that stroke becomes smaller, while the lowering of the float 7 causes the switching valve 34 to switch to lower the aircraft body via the sensor 58. Position D places the float pivot pin 13a in the lower position 1.
When the shallow seedling planting depth of 3a' is approached, the lower limit line C' of the float 7 is approached, and the switching valve 34
Because there is no longer a stroke to switch to raising the aircraft, or the stroke margin is reduced,
Also, the switching operation of the switching valve 34 in both of the above positions becomes impossible or incomplete, and the lifting and lowering movements of the aircraft become impossible or the speed of the lifting and lowering movements becomes slow. There is a problem where the height control is not stabilized.

In contrast, in the present invention, as described above, the relative position of the sensor 58 with respect to the float 7 is set in the vicinity of the upper limit stopper 18 and the lower limit stopper pin 20, and the switching valve 34 is connected to the float 7.
As shown in FIG. 14, the position U when the float 7 changes to raise the aircraft via the sensor 58 and the position D when the float 7 switches to lower the aircraft via the sensor 58 due to the lowering of the float 7 are as shown in FIG. , do not approach the upper limit lines B', B'' of the float and the lower limit lines C', C'' of the float, therefore, no matter how the seedling planting depth is adjusted, due to the switching operation of the switching valve 34. Since there is sufficient margin in the stroke of , and the switching operation at position U and position D can be completed, the lifting and lowering movements of the aircraft will no longer be possible or the speed of the lifting and lowering movements will become slow. This can definitely be avoided.

As described above, according to the present invention, when adjusting the seedling planting depth while regulating the vertical movement of the float within a certain height range, the seedling planting depth adjustment operation has an effect on the switching operation of the switching valve. Since adverse effects can be avoided, the height of the machine relative to the field can be controlled stably regardless of the adjustment of the seedling planting depth.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is a side view of the rice transplanter, Fig. 2 is a plan view of Fig. 1, Fig. 3 is a perspective view of the lifting mechanism, and Fig. 4 is a part of the hydraulic cylinder section. 5 is a partially cutaway side view of FIG. 4, and FIG. 6 is a cross-sectional view of FIG. 4,
Fig. 7 is a cross-sectional view of Fig. 4 as seen from above, Fig. 8 is an enlarged cross-sectional view of the main parts of the rice transplanter, Fig. 9 is an enlarged cross-sectional view of Fig. 8 as seen from -, and Fig. 10 is a - view of Fig. 9. 11 is an enlarged sectional view taken along line XI-XI in FIG. 8, FIG. 12 is a diagram of the manual lift lever, and FIG.
The right side view of Figure 2, Figure 14 is a diagram showing the relationship between seedling planting depth adjustment and the vertical movement of the float, and Figures 15 and 16 are diagrams showing the relationship between seedling planting depth adjustment and float movement prior to the invention. It is a figure showing the relationship with vertical movement. 1...Rice transplanter, 2...Mission case, 3...
...Engine, 5...Transmission case, 6...Airframe, 8
... Wheels, 7 ... Float, 12 ... Control handle, 13 ... Seedling planting depth adjustment rod, 17 ... Dogleg-shaped link mechanism, 21 ... Swing case, 29 ... Lifting arm, 23 ... Hydraulic pressure Cylinder, 24... Piston, 27... Swinging rod, 34... Hydraulic switching valve, 4
0...Rotating spool, 58...Sensor, 63...
... Control link, 65 ... Rod, 70 ... Regulation piece, 72 ... Adjustment stopper, 73 ... Long groove hole,
74...pin, 75...manual lift lever, 80...
...Wire, 84...Spring.

Claims (1)

[Scope of utility model registration request] The rear part of the float is pivoted to a body equipped with wheels that can move up and down, so that the front part of the float can freely move up and down, and a hydraulic cylinder for raising and lowering the wheels is used to raise the body. A switching valve for switching between neutral and lowering the aircraft is provided, and a sensor related to the float is connected to the switching valve, and when the height between the aircraft and the float increases, the switching valve changes to lower the aircraft when the height decreases. In a rice transplanter in which the switching valves are interlocked and connected so that the switching valves are respectively switched to raise the body, the body is provided with a stopper means at the front part of the float for regulating the maximum raising position and the maximum lowering position; A lifting device for a rice transplanter, characterized in that the relative position of the sensor relative to the float is set near the stopper means.