JPH0154967B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention connects a seedling planting device to a traveling machine via a single-acting hydraulic cylinder so that it can be driven up and down, and the seedling planting device detects the level of the seedling planting device relative to the planting mud surface. A grounding sensor is provided that can be raised and lowered, and a spool of a control valve for the hydraulic cylinder is interlocked with the sensor, and the sensor is connected to the seedling planting device based on the vertical displacement of the sensor with respect to the seedling planting device. A lift control mechanism is provided for automatically operating the valve to maintain the height within a set height range for the spool, and an operating lever is linked for forced operation from a neutral position to a lift operation position for the spool. Regarding rice transplanters.

In order to raise and lower the seedling planting device in the above rice transplanter, conventionally, the spool is operated upward from the neutral state for hydraulic locking in one direction, and then from the neutral state to the opposite side from the above-mentioned upward operation side. It is configured to be operated downward in conjunction with the operation to the side, and when controlling the elevation during planting work, each time the switch is switched from the descending state to the ascending state or from the ascending state to the descending state. It had the disadvantage that it had to go beyond the original neutral state, had poor responsiveness, tended to cause delays in control operations, and was unable to follow minute irregularities.

In view of the above-mentioned points, the present invention makes it possible to perform elevation control with high precision by following even minute irregularities, and effectively utilizes the configuration for this purpose for turning around on headlands, etc. To enable a valve to be configured compactly even though a seedling planting device that has been forcibly raised can be lowered, and to easily perform lifting and lowering operations for the seedling planting device and switching operation to a planting work state. With the goal.

Next, embodiments of the present invention will be described in detail based on illustrative drawings.

A seedling planting device 5 is interlocked and connected via a link mechanism 3 and a single-acting hydraulic cylinder 4 to the rear of a traveling vehicle body in which wheels 1 are mounted on front and rear wheels and a control unit 2 is arranged, so that the seedling planting device 5 can be driven up and down. It is configured as a riding rice transplanter.

A pair of left and right soil leveling floats 6, 6 arranged at the lower part of the seedling planting device 5 are integrally provided so as to be freely raised and lowered, and the seedling planting device adjusts to the planting mud surface based on the vertical displacement with respect to the seedling planting device 5. A lever portion 7a extends from brackets 7, 7 which pivotally support the rear end sides of the sensor floats 6, 6, and is configured to also serve as a ground sensor for detecting the level of
A control arm 10 that engages the spool 8 of the control valve V for the cylinder 4 with a pin 9 connected to the spool 8, a rotating shaft 11 to which the operating arm 10 is connected, and a wire 12 that connects the rotating shaft 11. The control valve V is automatically operated based on the vertical displacement of the sensor float 6 with respect to the seedling planting device 5, and the sensor float 6 The elevation control mechanism 14 is configured to maintain the seedling planting device 5 within a set range, that is, to maintain the level of the seedling planting device 5 relative to the planting mud surface within a set range. .

a cylindrical member 16 connected to the rotating shaft 11 with an arm 15 that can be forcibly operated only on the side that drives and raises the seedling planting device 5 by abutting against the pin 9;
At the same time, a manually operated lever 17 is interlocked and connected to the cylindrical member 16, and the lever 17 is attached to the spool 8.
It is configured such that the seedling planting device 5 can be forcibly driven upward when turning to change direction in a rice field or when driving on the road, regardless of whether or not the control mechanism 14 is activated. .

The operating lever 17 is reversibly swingable from a raised operating position U to a neutral position N while passing through an automatic control position A, and lowers the seedling planting device 5 from an elevated position where it is floated above the ground. At this time, the lever 17 is moved from the neutral position N to the automatic control position A.
When the lever is operated, the spool 8 is automatically operated by the descending biasing force of the sensor float 6 using the control mechanism 14, and when the sensor float 6 is in the working state where it is in contact with the ground, the lever is 17 to the automatic control position A allows the control mechanism 14 to perform an elevation control operation.

The arm 15 is configured in a plate shape, and in a state where the arm 15 is protruded at a predetermined distance from the first protrusion 15a that contacts the pin 9 for a lifting operation, the arm 15 can be operated in the opposite side to the lifting side. A second protrusion 15b that comes into contact with the pin 9 when the lever 17 is swung to forcibly operate it to the neutral position N is provided in series, and a first recess 18a is provided at a predetermined location on the plate surface of the arm 15.
and a second recess 18b, and on the other hand, case 1
A compression spring 21 is provided on the 9 side with a pawl 20 for selectively fitting into the recesses 18a and 18b.
The pole 20 is fitted into the first recess 18a, and the first
By contacting the protruding portion 15a, the spool 8 is prevented from being displaced to the neutral position N, and the seedling planting device 15 floating above the ground is maintained in a state where the lowering operation and the raising and lowering control during the planting work are performed, and the other , second recess 18b
The second protrusion 1 of the pin 9 is inserted into the pole 20.
5b, the spool 8 is maintained at the neutral position N, and the seedling planting device 5 is floated above the ground.
It is constructed to prevent displacement of the spool 8 due to unexpected displacement of the sensor float 6 due to machine body vibration, etc., and to ensure proper hydraulic locking.

The spool 8 of the control valve V includes:
As shown in FIG. 4, a first land 22 is formed at the end of the pin 9 on the mounting side for a lifting operation that cuts off the communication with the tank port b and communicates only the pump port c with respect to the cylinder side port a. , On the other hand, on the other end side, tank port b is connected to cylinder side port a.
A neutral second land 23 that does not communicate with any of the cylinder side port a, the tank port b, and the pump port c is formed between both lands 22 and 23 and connected to the second land 23. An underlap portion 24 is formed to allow both of the cylinders c to communicate with each other and to supply and discharge pressure oil to and from the cylinder 4 through pressure balance.

As shown in FIG. 6, the spool 8 is placed in the guide groove 25 for the operating lever 17 at the neutral position N.
A linear operation route R is provided for forced operation across the upper and lower operation positions U, and the underlap portion 24 is used to supply and drain pressurized oil to a position that is separated from the operation route R and is linearly connected only to the upper operation position U. A locking portion 26 is provided to prevent the spool 8 from being displaced from the neutral position N.

With the above configuration, when turning on a headland or traveling on the road, the seedling planting device 5 can be forcibly raised by operating the operating lever 17 to the raising operating position U, and the seedling planting device 5 can be raised to a neutral position after being raised to a predetermined height. By operating to N, the above-mentioned pawl 20 is fitted into the second recess 18b to maintain the hydraulic lock state (mechanical locking means is also used when traveling on the road), and turning is completed. Afterwards, when lowering the seedling planting device 5 that has been forcibly raised, operate the operating lever 17 to the locking portion 26 and maintain that state by fitting the pole 20 into the first recess 18a. By using the control mechanism 14, the seedling planting device 5 is automatically lowered until it touches the ground by lowering the spool 8 in accordance with the descending displacement of the sensor float 6, and after touching the ground, the seedling planting device 5 is lowered as shown in FIG. , the underlap portion 24 naturally
The lifting control mechanism 14 is activated, and the state in which pressure oil is supplied to the cylinder 4 and the state in which oil is drained from the cylinder 4 are established by cooperation between the pressure balance and the lifting displacement of the sensor float 6 with respect to the seedling planting device 5. It is configured so that it appears repeatedly and can follow even minute changes in the level of the planting mud surface.

As shown in FIG. 8, the operating lever 17 is
An arm 27 is provided in a row so as to protrude on both sides of the pivot axis, and a link 2 is provided at each end of the arm 27.
8 and 28 are connected, and a release wire 30 connected to the planting clutch 29 biased on the entry side is connected to the ends of the links 28 and 28 via long holes 31 and 31, and the operation lever 17 to raise operation position U
and when operated to neutral position N, both links 2
When the wire 30 is pulled through either one of 8 and 28, the planting clutch 29 is automatically disconnected, and the automatic control position A is operated, the wire 30 is pulled. Instead, the planting clutch 29 is maintained in the engaged state.

In the above embodiment, the leveling float 6 is used to detect the level of the seedling planting device 5 relative to the planting mud surface.
However, for example, a dedicated float or sled-like body may be provided, and these are collectively referred to as the ground sensor 6.

To hold the arm 15 at the neutral position N and the automatic control position A, the above-mentioned pole 20 is
The configuration is not limited to the configuration in which the operating lever 17 is fitted into each of the second recesses 18a and 18b, but may be configured such that the operating lever 17 is retained by an elastic force in an elastic locking portion made of a plate spring or the like.

In summary, the present invention provides, in the above-mentioned rice transplanter, a first spool for raising the spool 8 that allows only oil supply to the hydraulic cylinder 4 on one end side.
The land 22 has a neutral second land 23 on the other end side that prevents supply and discharge of pressure oil to the cylinder 4, and a pressure balance between the first land 22 and the second land 23, Said cylinder 4
Underlap portions 24 are respectively formed to repeatedly exhibit a state in which pressure oil is supplied to the cylinder 4 and a state in which pressure oil is drained from the cylinder 4.
A guide groove 25 for the spool 7 is provided with a path R for forcibly operating the spool 8 between a neutral position N and a rising operation position U, and, apart from the operation path R, pressure oil is supplied and discharged by the underlap portion 24. The spool 8 from the neutral position to the neutral position N
It is characterized by being provided with a locking portion 26 that prevents displacement.

In other words, by forming the underlap portion 24, the pressure is balanced, and the oil supply state to the cylinder 4, that is, the raised state of the seedling planting device 5, and the oil drainage from the cylinder 4 are controlled against minute displacements of the spool 8. condition, that is, the descending condition of the seedling planting device 5, it is possible to avoid the situation where the seedling planting device 5 exceeds the neutral position for the hydraulic lock every time it is repeatedly raised and lowered, as in the conventional case, and it can follow minute irregularities well. As a result, it has become possible to perform elevation control with high precision and efficiency.

In addition, when the seedling planting device 5 is forcibly raised such as when turning around on a headland and floating above the ground, pressure oil is supplied and discharged at the underlap portion 24, so that the sensor 6 detects the level of the seedling planting device 5. We focused on the fact that the control mechanism 14 naturally operates on the side where the seedling planting device 5 is high and lowers it, and not only lowers the seedling planting device 5, but also lowers the underlap portion 2 of the seedling planting device 5.
4 is formed between the first land 22 and the second land 23 of the spool 8, the lowering land, which was conventionally formed on the opposite side of the first land 22 to the second land 23, can be replaced. Can be made unnecessary, spool 8
It became possible to make the valve V more compact by making it shorter.

In addition, in order to operate the spool 8 to the neutral state, it is only necessary to slide the spool 8 to one of the operating limits, making it extremely easy to operate when hydraulically locking the seedling planting device 5 while it is floating above the ground. Now I can do it.

Furthermore, by positioning the lever 17 in the locking portion 26 of the guide groove 25, it is possible to lower the seedling planting device 5 which has been forcibly raised and to control the raising and lowering in the planting work state, and also to control the raising and lowering operation. By operating the seedling planting device 5 to position U, the seedling planting device 5 can be forcibly raised, and by operating it to the neutral position N along the operating path R, the hydraulic lock can be activated after the seedling planting device 5 is forcibly raised. The seedling planting device 5 can be easily fixed, and as a whole, the raising and lowering operation of the seedling planting device 5 and the switching operation to the planting operation state can be performed easily and satisfactorily.

[Brief explanation of drawings]

The drawings illustrate embodiments of the rice transplanter according to the present invention, in which Fig. 1 is an overall side view, Fig. 2 is a perspective view of main parts, Fig. 3 is a partially cutaway side view of a valve, and Fig. 4 is a side view of the main part. A partially cutaway plan view of the valve, Fig. 5 is the − of Fig. 3.
A line sectional view, FIG. 6 is a plan view of the guide groove, FIG. 7 is a schematic plan view of the main part of FIG. 4 showing the automatic control state,
FIG. 8 is a view taken along the - line in FIG. 6. 4... Cylinder, 5... Seedling planting device, 6... Sensor, 8... Spool, 14... Lifting control mechanism, 17... Operating lever, 22... First land,
23... Second land, 24... Underlap portion, 25... Guide groove, 26... Locking portion, U... Raising operation position, N... Neutral position, R... Operation route,
V...control valve.

Claims (1)

[Claims] 1. A seedling planting device 5 is connected to the traveling machine via a single-acting hydraulic cylinder 4 so that it can be driven up and down, and the seedling planting device 5 is equipped with a ground sensor 6 for detecting its level with respect to the planting mud surface. The sensor 6 is provided so as to be movable up and down, and the spool 8 of the control valve V for the hydraulic cylinder 4 is interlocked with the sensor 6, and the sensor 6 is connected to the spool 8 of the control valve V for the oil pressure cylinder 4. an elevation control mechanism 1 that automatically operates the valve V to maintain the device 5 within a set height range;
4, and an operating lever 17 is linked to the spool 8 so as to be forcibly operated from a neutral position N to an upward operating position U. 4
The first land 22 for ascending operations that only allows refueling
, a neutral second land 23 for blocking the supply and discharge of pressure oil to the cylinder 4 on the other end side, and an intermediate land between the first land 22 and the second land 23,
Underlap portions 24 are formed in each of the guide grooves 25 for the operation lever 17 to repeatedly exhibit a state in which pressure oil is supplied to the cylinder 4 and a state in which pressure oil is discharged from the cylinder 4 by pressure balance. A path R is provided for forcibly operating the spool 8 between a neutral position N and a raising operation position U, and a path R is provided in which the spool 8 is forcibly operated from a position where pressurized oil is supplied and discharged by the underlap portion 24 to a neutral position N, deviating from the operation path R. A rice transplanter characterized in that a locking portion 26 is provided to prevent displacement of the spool 8.