JPS6317308Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a longitudinal balance control device for a rice transplanter.

Conventionally, in rice transplanters, wheels are attached to a swing case whose base end is pivoted to the left and right sides of the machine so that it can move up and down, and a traveling device that moves the swing arm up and down allows rice transplanters to be used regardless of the plowing depth. The ground pressure of the float was kept constant. In this case, for example, if a swing arm of a constant length has its base end protruding forward of the aircraft and the end where the wheels are attached protrudes rearward, if the swing arm is rotated downward, the wheels will move accordingly. The position of the axle will move to the front of the aircraft, and the center of gravity of the aircraft relative to the wheels will shift to the rear, which will disrupt the longitudinal balance of the aircraft, worsening the aircraft's maneuverability, and causing the rear ground pressure of the float to become too large. There was a drawback that the seedling planting depth and seedling planting posture could not be made constant.

In this invention, a sensing device is installed on the upper surface of the rear part of the float attached to the lower surface of the fuselage to detect the ground pressure at the rear of the float, while the wheel cases attached to the left and right sides of the fuselage are made to be able to expand and contract back and forth, and the wheels of the wheel cases are By moving the rear section forward and backward through a hydraulic cylinder and link mechanism that respond to the sensing device, the front-to-back balance of the machine can be kept constant regardless of changes in the depth of the plow and the amount of seedlings, and the seedling planting depth can be adjusted. This makes it possible to keep the angle constant and make it easier to turn the aircraft.

Next, an example of the present invention will be explained with reference to the drawings.
In the figure, 1 is a fuselage 6 which has a frame 4 of an engine 3 connected to the front part of a transmission case 2, and a transmission case 5 to the rear thereof, and a float 7 on the lower surface of the fuselage 6.
The rice transplanter shown in FIG. 12, a pair of control handles 13, and floats 8, 9 on the outside of the wheels 9, 9.
8. The middle part of each seedling planting depth adjustment rod 15 is pivoted by a pin 16 to a bracket 14 protruding from the body of the handle 13, etc., and the upper part of each adjustment rod 15 is supported slidably along a guide locking piece 17. The height H between the floats 7, 8, 8 and the body 6 is adjusted by connecting the lower end of each adjustment rod 15 to each bracket 18 protruding from the rear upper surface of the floats 7, 8, 8. At this time, the bracket 18 of the center float 7 has a pin 19 projecting left and right from the adjustment rod 15 with an appropriate size h.
A long groove hole 20 that can be moved up and down by a certain amount is bored, and a compression spring 19'' is installed between the pin 19 and the float 7.

Furthermore, a link 21 is provided on the bottom surface of the tip of the above-mentioned plate 4.
A sliding part 22 is provided at the lower end of the link 21, and the link 21 is connected via a pin 24 provided on a bracket 23 protruding from the upper surface of the front end of the center float 7. The left and right floats 8, 7 are movable up and down, and are attached to the tips of horizontal bars 25, 25 which protrude laterally from the fuselage 6 via links 26, 26 having the same structure as the link 21.
8 is installed so that it can move up and down.

Reference numeral 27 denotes a traveling device, and its telescopic left and right wheel cases 28, 28 have a base end of each base side case 29 connected to a drive shaft 31 protruding from the left and right side surfaces of the transmission case 2.
Rotatably attached to each base side case 29
The distal end case 30 is attached to the distal end case 30 so as to be slidable back and forth, and the wheel 9 is attached to the distal end of each distal end case 30 via an axle 32. Drive shaft 31 through
Power is transmitted from the axle 32 to the axle 32.

Then, both the left and right wheels 9, 9 are connected to the hydraulic cylinder 33.
In constructing the structure so as to be movable back and forth via the link mechanism 34, a pair of left and right vertical rings 35, 35, which are opposed to each other with their lower end bases rotatably pivoted to the left and right sides of the transmission case 5, respectively, are provided horizontally. The rod 36 is made to protrude outward and the left and right ends of the horizontal rod 36 are connected to the respective distal end side cases 30, 30 by connecting rods 37, 37, while a single acting hydraulic cylinder 33 is installed on the upper surface of the transmission case 5. and connect the piston rod 38 and the upper ends of both the links 35, 35 with a pin 39,
The hydraulic cylinder 33 is actuated by a hydraulic pump 41 on the upper surface of the transmission case 5 driven by a belt 40 from the engine 3 to move the two end side cases 30, 30 back and forth simultaneously. If the center of gravity shifts to the rear and the ground pressure at the rear of the float 7 increases, the wheels 9, 9 move backward; on the other hand, if the center of gravity shifts to the front and the ground pressure at the rear of the float 7 decreases, the wheels 9, 9 move forward. In configuring the float to move, a float ground pressure sensing device is provided between the rear upper surface of the float 7 and the tip of the seedling planting depth adjustment rod 15. That is, a hydraulic control valve 42 such as a throttle valve or a flow rate regulating valve is provided near the bracket 18 on the upper surface of the central float 7, and a hydraulic control valve 42 such as a throttle valve or a flow rate regulating valve is provided from the upper end of the spool 44 of the valve 42 to the upper surface of a pin 19 integrally provided from the regulating rod 15. The protruding lever 43 is biased by a spring 45 so as to be in constant pressing contact, and when the spool 44 of the hydraulic control valve 42 is lowered, the hydraulic pressure from the hydraulic pump 41 to the hydraulic cylinder 33 increases; A hydraulic circuit is formed so that oil from the hydraulic cylinder 33 returns to the tank 46 when the pressure rises.

Reference numeral 27' denotes an elevating mechanism for the traveling device 27, and bell crank type elevating levers 47, 47 are provided on both left and right sides of the mission case 2, and are rotatably inserted into a shaft 48 that is supported through the mission case 2. , the tips of the two lifting levers 47, 47 are connected to the two base side cases 29, 29 via rods 49, 49, respectively, while the frame 4 of the engine 3 is formed to have a rectangular cylindrical cross section, and inside thereof A single-acting hydraulic cylinder 50 is provided so that its piston 51 protrudes forward along the center line of the rice transplanter 1, and a planar T-shaped connecting body 52 is rotatably connected to the tip of the piston 51. Both ends of this connecting body 52 are connected to the other ends of the elevating levers 47, 47 via connecting rods 53, 53, respectively, so that both wheels 9, 9 move up and down simultaneously by the operation of the hydraulic cylinder 50. Configure the aircraft to move up and down.

The hydraulic pump 41 is provided with a 4-port 3-position switching valve 54, and a circuit 5 is connected to the pump port P.
The hydraulic pump 41 is connected to the hydraulic pump 41 through the circuit 56, the port A is connected to the inlet port to the hydraulic cylinder 50 through the circuit 56, the return ports R ₁ and R ₂ are connected to the oil tank 46, and the inside of the switching valve 54 is spool 5
7 is in the neutral position, ports A and R ₁ are closed and ports P and R ₂ are in communication with each other, and when the spool 57 moves to the front of the aircraft, ports R ₁ and R ₂ are closed and ports P and A are in communication with each other. When the wheels 9, 9 are lowered by the forward motion of the piston 51 in the hydraulic cylinder 50, which communicates with each other, and the body is raised, and the spool 57 moves to the rear of the body, ports P, R ₂ and ports A, R _{1 are} connected to each other. The two wheels 9, 9 are connected to each other so that the backward movement of the piston 51 in the hydraulic cylinder causes both wheels 9, 9 to rise, thereby lowering the machine body.

Reference numeral 58 denotes a sensor which is pivoted to the lower part of the frame 4 of the body 6 so that its tip is in contact with the upper surface of the central float 7, and the sensor 58 is connected to the other end of the bell crank lever 59 to which the spool 57 is attached.
When the sensor 58 rotates downward, the switching valve 54 switches to lower the aircraft, and when the sensor rotates upward, the switch valve 54 switches to raise the aircraft.
The other end of the bell crank lever 59 is connected via a link mechanism 62 to a manual lever 61 provided at an appropriate location on the operating handle 13, etc. The aircraft is also configured so that it can be raised and lowered.

In this configuration, in order to carry the rice transplanter into the field and perform rice transplanting work, if the adjustment rod 15 is fixed at a predetermined angle θ with respect to the machine body in advance, the maximum distance between the float 7 and the machine body 6 can be regulated. In this state, if the manual lever 61 is once moved to the aircraft-up position and the aircraft rises significantly, and then the manual lever is released, the sensor 50 will rotate downward so as to come into contact with the upper surface of the float 7, and the switching valve 54 will be rotated downward. switches to lowering the body and the body 6 begins to descend, and after the float 7 touches down on the field, the distance between it and the body gradually approaches, and eventually the spring 19'' force between the float 7 and the pin 19 and the float grounding pressure is balanced and the height of the float and the machine reaches the predetermined rice transplanting height, the switching valve 54 is returned to the neutral position as the sensor 58 in contact with the top surface of the float 7 rotates upward. As a result, the machine body stops descending, and the height of the machine body relative to the field scene can be automatically set to a predetermined rice planting height position.

In this advancing state, if the tiller becomes deeper, in other words, if the distance between the front part of the fuselage 6 and the float 7 becomes smaller, the sensor 58 rotates upward and the piston 51 of the hydraulic cylinder 50 moves forward. The axle cases 28, 28 are rotated downward about the drive shafts 31, 31 via the bell crank levers 47, 47. Along with this, axle 3
The longitudinal center of gravity of the aircraft for 2 moves backward from the previous center of gravity, the rear of the aircraft tilts downward, the rear of the float 7 is pressed against the field, the ground pressure increases, and the pin 19 of the adjustment rod 15 and the float Since the vertical distance h ₁ from the top surface of 7 becomes small, the spring 4
5 force causes the spool 44 to descend together with the lever 43 that is in contact with the upper surface of the pin 19, and the hydraulic control valve 4
2 becomes large, oil from the hydraulic pump 42 is sent to the hydraulic cylinder 33, the piston 38 protrudes, and the connecting rods 37, 37 are moved rearward via the link mechanism 34, and both end side cases 30, 30 are pulled out. As the lengths of both axle cases 28 and 28 have become longer, the longitudinal center of gravity of the aircraft with respect to the axles 32 and 32 of both wheels 9 and 9 does not change regardless of the downward rotation of the axle cases 28 and 28. This is because the center of gravity of the machine can be supported at a position close to the axle 32, and the longitudinal balance of the machine is not disturbed. On the other hand, if the plowing platform becomes shallower, the distance between the front part of the float 7 and the machine body 6 becomes larger, and each part operates in the opposite manner to that described above, causing both axle cases 28, 28 to rotate upward.
Also at the rear of float 7, pin 19 and float 7
The distance h ₁ from the hydraulic cylinder 33 to the tank 46 increases (the ground pressure is small), the spool 44 protrudes by the spring 45, the throttle of the hydraulic control valve 42 is opened, and the oil returns from the hydraulic cylinder 33 to the tank 46, opposite to the above link. Both tip side cases 30, 30 are pushed toward base side cases 29, 29 via mechanism 34 and connecting rods 37, 37, and both axle cases 28, 28 act to shorten. Therefore, regardless of the shallowness or depth of the tiller,
This allows the front-to-back balance of the aircraft to be kept constant.

Further, when the body 6 is turned in the field, the body 6 is raised greatly to minimize the ground pressure of the float 7 on the field, thereby making it easier to turn. To do this, both axle cases 28, 28 are rotated significantly downward by operating the manual lever 61, but as a result, the axles 32, 32 move forward of the aircraft, and the aircraft tilts backward, causing the rear part of the float 7 to move forward. As a result, the distance h ₁ between the float 7 and the pin 19 becomes smaller, the restriction of the hydraulic control valve 42 becomes larger, and the lengths of both axle cases 28 and 28 become longer. Therefore, the axles 32, 32 of both wheels 9, 9 move backward, and the center of gravity of the aircraft with respect to the axle 32 position moves toward the front of the aircraft, resulting in forward balance or approaching the axle 32 position, and the float This eliminates the need for the rear part to press or sink into the field, reducing the load on the handlebars and making turning maneuvers extremely easy.

Furthermore, even if the depth of the tiller is constant, the seedling platform 1
If the seedling pine on the 0 is long, the center of gravity of the machine will shift to the rear, and if the seedling pine is consumed and decrease, the center of gravity of the machine will move forward, causing a change in the center of gravity. In this case, both axle cases 28, 28 does not rotate up and down, and when the ground pressure at the rear of the float 7 is large, both axle cases 28, 28 are extended and the axle 32,
32 position is moved backward, and conversely, when the rear ground pressure of the float 7 becomes smaller, both axle cases 28, 28 are shortened and the axle 32 position is moved forward. By varying the axle positions of the wheels 9, 9, the longitudinal balance of the aircraft can be kept constant.

Further, the planting depth of seedlings in the field can be increased or decreased by moving the rear part of each float 7, 8 up and down with respect to the body 6 by rotating the seedling depth adjustment rod 15. However, the hydraulic control valve 4
2. A float ground pressure sensing device composed of a lever 43, a spring 45, etc. is connected to the seedling planting depth adjusting rod 15.
Since this float ground pressure sensing device is provided between the tip of the float 7 and the float 7, it moves up and down together with the float when adjusting the seedling planting depth, so that the float ground pressure sensing device can be used to control the airframe. The automatic control of the longitudinal balance does not change due to the adjustment of the seedling planting depth. In other words, the automatic control of the longitudinal balance of the machine body can be maintained at any seedling planting depth.

As described above, the present invention consists of a pair of left and right axle cases which are pivotally connected to the fuselage so as to be able to move up and down, and are configured to be extendable and retractable in the longitudinal direction, and wheels are provided at the tips of the axle cases. , a float that slides on a field is provided, the rear part of the float is attached to the machine body via a seedling depth adjustment rod, and the two axle cases are simultaneously extended and retracted to the machine body. In a rice transplanter equipped with a hydraulic cylinder, the attachment part of the rear part of the float to the seedling planting depth adjustment rod is configured so that the rear part of the float can freely move up and down by an appropriate distance, and the seedling planting depth of the float is adjusted. A float ground pressure sensing device is installed between the height adjustment rod and detects the vertical movement of the rear part of the float relative to the machine body to drive the telescopic hydraulic cylinder. Since the longitudinal balance of the machine can be maintained approximately constant regardless of changes in the amount, it is possible to stabilize the planting of seedlings in the field.

Moreover, the present invention is based on the prior art published in Japanese Patent Application Laid-open No. 1973
It has the following effects compared to the rice transplanter described in Publication No.-68814.

That is, in the rice transplanter of the prior art, a sensor that is grounded in the field is directly attached to the machine body, and the sensor automatically expands and contracts both the left and right axle cases, thereby maintaining the longitudinal balance of the machine body. Therefore, when the rear part of the float is moved up and down relative to the aircraft body in order to adjust the planting depth of seedlings in the field, the sensor attached directly to the aircraft and the field As the relative positional relationship with the surface changes, it becomes impossible to control the longitudinal balance of the aircraft body at a constant level.

In contrast, the present invention uses a float ground pressure sensing device to extend and retract both the left and right axle cases according to the height of the machine relative to the field, as described above, to adjust the seedling planting depth. The float ground pressure sensing device moves up and down together with the float when adjusting the seedling planting depth.
The automatic control of the longitudinal balance of the aircraft by this float ground pressure sensing device does not change even when the seedling planting depth is adjusted. It can be maintained even in the middle of the day.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is a side view of a walk-behind four-row rice transplanter, Fig. 2 is a plan view thereof, Fig. 3 is an enlarged side view of the connection between the rear part of the machine and the float, and Fig. 4 is a sectional view taken along the line -- in FIG. 5, FIG. 5 is a hydraulic circuit diagram of the float rear ground pressure, and FIG. 6 is a hydraulic circuit diagram of the axle case rotation drive. 1... Rice transplanter, 6... Body, 7, 8, 8... Float, 9, 9... Wheels, 10... Seedling stand, 1
3, 13... Handle, 15... Seedling planting depth adjustment rod, 27... Traveling device, 27'... Lifting mechanism, 2
8, 28...Axle case, 29, 29...Proximal end case, 30, 30...Distal end case, 31...
Drive shaft, 32, 32... Axle, 33, 50... Hydraulic cylinder, 38, 51... Piston, 34...
Link mechanism, 35, 35... Vertical link, 37, 3
7... Link, 41... Hydraulic pump, 42... Hydraulic control valve, 44... Spool, 45... Spring, 20
...Long slot, 19...pin.

Claims (1)

[Scope of utility model registration request] A pair of left and right axle cases are pivotally connected to the machine body so as to be able to move up and down, and are configured to be expandable and retractable in the longitudinal direction, and wheels are provided at the tips of the axle cases. , the rear part of the float is attached to the machine body via a seedling depth adjustment rod, and the machine body is provided with a hydraulic cylinder for simultaneously expanding and contracting both the axle cases. In the machine, the attachment part of the rear part of the float to the seedling depth adjustment rod is configured so that the rear part of the float can freely move up and down by an appropriate distance, and the part between the seedling planting depth adjustment rod of the float and A balance control device for a rice transplanter, characterized in that a float ground pressure sensing device is provided, which senses the vertical movement of the rear part of the float relative to the machine body and drives the telescopic hydraulic cylinder.