JPH0155847B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is equipped with a small propulsion wheel that can be steered freely in the left and right center of the front part of the fuselage, and a seedling planting device with a plurality of floats arranged in parallel is connected to the rear part of the fuselage. A sled body that is driven up and down by a hydraulic cylinder is installed at the lower left and right center position of the rear, and the hydraulic cylinder is controlled based on the ground pressure detection result of a ground sensor installed at the rear of the aircraft to set the sensor ground pressure within a range. The present invention relates to a rice transplanter configured to be maintained within a certain area. In a rice transplanter with such a configuration, the propulsion wheels located at the left and right center of the front of the machine and the sled body located at the left and right center of the rear of the machine are grounded on the tiller, and the parallel floats at the rear of the machine are grounded on the field surface. Since the machine travels in a shape that supports the weight of the machine, it has the characteristic of being able to travel straight without being affected by the left-right inclination of the tiller or the difference in unevenness between the left and right sides of the tiller. At times, the aircraft had poor lateral stability. One of the ways to solve such problems is to
Separate sled bodies are installed at the left and right positions below the rear of the aircraft,
It is being considered that only the center sled body is used to touch the ground during normal planting runs, and that only the left and right sled bodies are used to ground the aircraft when changing direction, thereby stabilizing the aircraft. However, if these sled bodies are moved up and down using separate operation levers, the switching operation becomes cumbersome, and in order to simplify this switching operation, it is necessary to link both sled bodies to move up and down in a reverse manner. During normal planting operation, the left and right sleds also move up and down as the central sled moves up and down.
There was a risk that the left and right sleds would rise and fall inappropriately in the mud, causing damage to the field. The present invention aims to solve the above-mentioned inconvenience when using the central sled body and the left and right sled bodies together,
In the rice transplanter having the configuration described above, a pair of left and right sled bodies that are integrally driven up and down by hydraulic cylinders are provided on both left and right sides of the rear lower part of the machine body, and a control valve mechanism for the hydraulic cylinders for raising and lowering the left and right sled bodies and the above-mentioned sled bodies are provided. an automatic control state in which a control mechanism for a hydraulic cylinder for lifting the central sled body is linked to one operating lever, and the central sled body is automatically operated based on the detection operation of the ground sensor by operating the operating lever; The left and right sled bodies are configured to be freely switched to a lifted state in which the left and right sled bodies are driven down and the rear part of the machine is forcibly raised, and in the automatic control state, the left and right sled bodies are set in a freely ascending and descending state;
The control valve mechanism of both the hydraulic cylinders is configured so that the center sled body is in a freely ascending and descending state when the body is in the lifted state, and the left and right sled bodies are biased in the upward direction. In other words, during normal planting runs, only the central sled is in contact with the tiller, and the elevation is controlled based on the detection results of the ground sensor to ensure good straightness. Since the sled body is retracted and swung upward by the biasing force and held, good planting is possible without damaging the field due to inappropriate elevation and descent of the left and right sled bodies. Embodiments of the present invention will be described below based on illustrative drawings. As shown in FIG. 1, the rice transplanter of the present invention has a front traveling body composed of an engine 1, a transmission case 2, and one propulsion wheel 3 located in the center of the left and right,
A rear body equipped with a seedling planting device 4 for planting four rows, a driver's seat 5, and a control handle 6 is connected to the rear of this traveling body, and by rotating the control handle 6, the front traveling body can be controlled. The structure is such that the fuselage direction is determined by bending and rotating the rear fuselage around the vertical axis X. In the rear fuselage, there is a rod-shaped sled body 7 that swings up and down using the front end as a fulcrum at the left and right center of the fuselage, and a pair of fuselage bodies 8, 8 that swing up and down integrally on the left and right sides of the fuselage, using the front end as a fulcrum. extends downward from the seedling planting device 4, and the central sled body 7 is driven to swing by a single-acting hydraulic cylinder 9, and the left and right sled bodies 8, 8 are driven to swing by separate single-acting hydraulic cylinders 10. It is configured like this. Further, each sled body 7, 8 has a spring 11,
12, it is urged to swing upward. At the bottom of the seedling planting device 4 , there is a pair of side floats 13 for leveling the planting area, one row on each side.
13 and one central float 14 for leveling the two central rows of planting areas are each mounted so as to be able to swing up and down about the rear fulcrum, and the central float 1
4 is used as a ground sensor for height control of the seedling planting device 4 , and the center sled body 7 is used to maintain the ground pressure of the sensor float 14 within a set range.
A mechanism is provided to automatically control the elevation. FIG. 3 shows a schematic configuration of the automatic elevation control mechanism, in which the rear part of the sensor float 14 is pivoted to one end of a bell crank 15 that is pivoted to the fixed frame portion of the seedling planting device 4, The other end of this bell crank 15 is connected to the spool 17 of the control valve 16 for both the hydraulic cylinders 9 and 10 in the link mechanism 1.
8, and this link mechanism 18
A spring 19 is provided therein for biasing and rotating the bell crank 15 to elastically press the rear fulcrum of the sensor float 14 in the direction of contact with the ground. The control valve 16 can be switched to four states as shown in FIGS. 5(i), (ii), (iii), and (iv). 1st position (i) When the spool 17 is pulled out the most, the pump port P
is communicated with the first connection port A to the central sled body hydraulic cylinder 9, and the second connection port B to the left and right sled body hydraulic cylinders 10 is communicated with the tank port _T1 via the drain oil passage d. As a result, the central sled body 7 is driven downward, and the left and right sled bodies 8 are freed and swung upward by the tension of the spring 12. 2nd position (ii) When the spool 17 is pushed in one step, the pump port P
and tank port _T2 are communicated via oil passage C in the spool, supply pressure oil is short-circuited and discharged, and at the same time, the first connection port A is closed and oil can be drained from the second connection port B. , the central sled body 7 is fixed by hydraulic locking, and
The left and right sled bodies 8 can be swung upward by spring tension. Third position (iii) When the spool 17 is pushed in two steps, the supply pressure oil is short-circuited and discharged, allowing oil to be discharged from the second connection port A, and the second connection port B is closed. As a result, the central sled body 7 can be swung upwardly by the tension of the spring 11, and the left and right sled bodies 8
is fixed by a hydraulic lock. Fourth position (iv) When the spool 17 is pushed in the most, the pump port P is communicated with the second connection port B via the spool internal oil passage C, and oil can be drained from the first connection port A. . Therefore, the center sled body 7 is swung upward by the spring tension, and the left and right sled bodies 8 are driven downward. The control valve 16 is also configured to be operable by a manual lever 21 connected to the planting clutch 20 by wire. That is, an arm 22 integrally connected to the lever 21 and one end of the intermediate balance link 23 are linked by a rod 24, and a long hole 26 is formed at the tip of a rod 25 extending from the other end of the link 23. A spring receiving pin 8 provided at the upper end of the T-shaped link 27 in the link mechanism 18 is engaged in the elongated hole 26. Then, when the manual lever 21 is held at the operating position A within the planting clutch engagement range ON, as the spool 17 is displaced from the first position (i) to the third position (iii), the pin The relative relationship of each part is set so that 28 can move within the elongated hole 26. Therefore, in this lever operation state, the left and right sled bodies 8, 8 remain in the raised position, only the center sled body 7 is in contact with the tiller, and the sensor float 1 is in contact with the tiller.
Elevation is controlled based on ground pressure fluctuations at 4. That is, when the float ground pressure is balanced with the load of the spring 19, the spool 17 is in the second position (ii), and the height of the seedling planting device 4 at this time becomes the reference. When the ground pressure of the sensor float 14 increases beyond the set range, such as when the machine reaches a deep part of the tiller, the T-shaped link 27 is rotated counterclockwise against the spring 19, and the spool 17 is rotated counterclockwise against the spring 19. It is switched to the first position (i), and the central sled body 7 is controlled to descend until the float ground pressure returns to the set range. Conversely, if the ground pressure of the sensor float 14 decreases due to reaching a shallow part of the tiller, etc., the T-shaped link 2
7 rotates clockwise and the spool 17 is in the third position.
(iii), and the central sled body 7 is controlled to rise freely until the float ground pressure returns to within the set range. In this way, by controlling the central sled body 7 to rise and fall so as to maintain the ground pressure of the sensor float 14 within the set range, the height of the seedling planting device 4 relative to the field is maintained stably. During planting, the rear load of the machine is supported by the central sled body 7, so the machine moves straight without being affected by the left-right inclination of the tiller or uneven steps. Furthermore, when the manual lever 21 is switched to operation position B within the planting clutch cutting range OFF, the pin 28 is locked to the front end (the left end in the figure) of the elongated hole 26, as shown by the imaginary line in FIG. The spool 17 is forcibly displaced as follows, and the spool 17 is switched to the fourth position (iv). In this state, the left and right sled bodies 8 are driven down, and the center sled body 7 is freely raised.
When changing the direction of the aircraft in the field or driving on the road, the aircraft is stably supported in a three-point ground contact state by the front propulsion wheels 3 and the pair of left and right sled bodies 8, 8 at the rear. Further, an arm 30 is protruded from the support shaft 29 of the left and right sled bodies 8, and a check rod 31 pivotally extended from the arm 30 is slidable on a rotation pin 32 provided at the lower end of the T-shaped link 27. is inserted into the
When the left and right sled bodies 8 are lowered to a predetermined height as described above, the stopper 33 fixed to the check rod 31 comes into contact with the pin 32 and the T-shaped link 27
is pressed and rotated counterclockwise, whereby the spool 17 is displaced to the third position (iii), and the left and right sled bodies 8 are
The descent of the plane is now stopped. and,
By adjusting the fixed position of the stopper 33 with respect to the rod, the lowering stop position of the left and right sled bodies 8 can be changed. Incidentally, when the spool 17 is automatically switched to the third position (iii) by the check rod 31 as described above, the manual lever 21 moves from the operating position B to the operating position C. In the lever 2
1 is elastically engaged and held in the recess 35 of the lever guide hole 34. Further, in the link mechanism 18, a sensor float 14 moves the spool 17 to the first position.
A contact regulating mechanism 36 is provided to regulate the stroke so that the spool 17 can be displaced only in the range from position (i) to third position (iii), and the spool 17 is moved to fourth position (iv) by manual lever 21. An elastic accommodating mechanism 37 is provided to allow for displacement. In the embodiment, the hydraulic cylinder 9 of the central sled body 7 and the hydraulic cylinders 10 of the left and right sled bodies 8 are connected to one control valve 1.
However, each hydraulic cylinder 9, 10 is connected to a separate valve mechanism, and the valve mechanism of the hydraulic cylinder 9 is linked to the sensor float 14, and both valve mechanisms are connected to one operating lever 21. It is also possible to perform the same operation as above in conjunction with the above.

[Brief explanation of drawings]

The drawings illustrate embodiments of the rice transplanter according to the present invention, FIG. 1 is an overall side view, FIG. 2 is an overall plan view,
FIG. 3 is a configuration diagram of the control mechanism, FIG. 4 is a side view showing essential parts of the control mechanism, and FIGS. 5(i) to (iv) are sectional views showing each operating state of the control valve. 3... Propulsion wheel, 4... Seedling planting device, 7... Central sled body, 8... Left and right sled body, 9... Hydraulic cylinder,
10...Hydraulic cylinder, 21...Operation lever, 1
6...control valve, 17...spool.

Claims (1)

[Claims] 1. A narrow propulsion wheel 3 is equipped in the left and right center of the front part of the fuselage so that it can be steered freely, and a plurality of floats 1 are installed.
A seedling planting device 4 in which seedlings 3 and 14 are arranged side by side is connected to the rear of the machine, and a sled body 7 that is driven up and down by a hydraulic cylinder 9 is installed at the left and right center position at the lower rear of the machine. In a rice transplanter configured to control the hydraulic cylinder 9 based on the ground pressure detection result of the sensor to maintain the sensor ground pressure within a set range, the rice transplanter is integrated with hydraulic cylinders 10 at both left and right positions at the lower rear of the machine body. A pair of left and right sled bodies 8, 8 which are driven up and down by driving are provided, and the control valve mechanism of the hydraulic cylinder 10 for raising and lowering the left and right sled bodies and the control valve mechanism of the hydraulic cylinder 9 for raising and lowering the central sled body are controlled by one operating lever. 21, and by operating this operating lever 21, the central sled body 7 is automatically operated based on the detection operation of the ground sensor, and the left and right sled bodies 8 are driven and lowered. The structure is configured such that it can be freely switched to a body raising state in which the rear part of the body is forcibly raised, and in the automatic control state, the left and right sled bodies 8 are in a free raising/lowering state, and in the body raising state, the center sled body 7 is in a free raising/lowering state. The control valve mechanisms for both the hydraulic cylinders 9 and 10 are constructed so that the left and right sled bodies 8,
A rice transplanter characterized in that 8 is biased in an upward direction. 2. The control valve mechanism of the central sled body lifting hydraulic cylinder 9 and the control valve mechanism of the left and right sled body lifting hydraulic cylinders 10 are incorporated into a control valve 16 having one spool 17, and this spool 17 is integrated into the control valve 16 having one spool 17. The rice transplanter according to claim 1, wherein the rice transplanter is configured to be switchable by a ground sensor and the operating lever 21.