JP2000300017A - Paddy working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reasonably provide a rice transplanter capable of regulating its lift control sensitivity. SOLUTION: This paddy working machine has such a scheme that, an operative wire 47 transmitting the posture change of a sensing float is made up from inner wire 47A and outer wire 47B and a travel machine body 3 is mounted with a level sensor 67 for measuring the working level of the inner wire 47A, thereby forming a system for electrically measuring the height of a seedling planting device A above the field surface and forming a system for controlling the support position for the outer wire 47B with a sensitivity control lever 14, thus controlling the relationship between the height measured by the level sensor 67 and actual height and thereby enabling the target posture of the sensing float to be controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic actuator for driving and lowering a ground working device provided on a traveling body so as to be movable up and down, and a control valve for supplying and discharging hydraulic oil to and from the actuator. An operation wire for taking out a relative height between a field scene and a ground work device based on a displacement of a ground float provided in a state where the work device is biased downward by a spring, and a ground work taken out with the operation wire The present invention relates to a paddy field working machine having control means for operating the control valve based on the relative height of the apparatus to move the ground working apparatus up and down following a field scene. The present invention relates to a technique for controlling the lifting and lowering of a ground working device by electric control by measuring with a potentiometer type sensor or the like provided in a body.

[0002]

2. Description of the Related Art There is a paddy field working machine constructed as described above in Japanese Unexamined Patent Publication No. 9-10311. In this prior art, a leveling machine is provided for a seedling planting apparatus as a ground working apparatus. The vertical displacement of the float is measured by a sensor provided on the body, and the raising and lowering control is performed so as to maintain the measurement result at a preset value, so that the seedling planting apparatus follows the field scene and moves up and down. I have.

[0003]

However, when the ground work apparatus is moved up and down following a field scene, it is necessary to move the ground work apparatus up and down with a control sensitivity corresponding to the hardness of the field scene. Specifically, in the case of a soft field scene containing moisture, it is difficult to catch the level change of the field scene, so that the pressure at which the grounding float comes into contact with the field scene is reduced, and the dead zone width of the control is narrowed to be high. It is necessary to control the sensitivity. Conversely, in the case of a hard field with little moisture, the pressure at which the ground float comes in contact with the field scene is increased in order to eliminate the control due to the influence of the small unevenness of the field scene. In addition, it is necessary to control the low sensitivity by widening the dead zone of the control, and a rational control sensitivity adjustment system is desired.

An object of the present invention is to rationally configure a paddy working machine that can easily set the sensitivity of elevation control.

[0005]

A first feature (claim 1) of the present invention is a hydraulic actuator for driving and lowering a ground working device provided on a traveling body so as to be movable up and down, and a hydraulic oil for the actuator. An operation for extracting the relative height between the field scene and the ground work device based on the displacement of the ground float provided in a state of being biased downward by a spring with respect to the ground work device while providing a control valve for supplying and discharging the ground A paddy working machine comprising a wire, and control means for operating the control valve based on a relative height of the ground working device taken out by the operation wire to move the ground working device up and down following a field scene. A level sensor provided on the traveling body side so that the control valve is constituted by an electromagnetic valve, and the control means electrically measures an operation amount of an inner wire of the operation wire; And a control device that outputs a signal for controlling the control valve based on the signal, and the relationship between the measured ground height of the ground working device measured by the level sensor via the operation wire and the actual ground height of the ground working device. The function and the effect are as follows.

According to a second feature of the present invention (claim 2), in claim 1, the sensitivity adjustment means mechanically adjusts an operation reference position of the operation wire by adjusting a position of an outer wire of the operation wire on a traveling machine body side. It is constituted by a sensitivity adjusting lever for changing and adjusting, and its operation and effect are as follows.

A third feature of the present invention (claim 3) is the sensitivity according to claim 1, wherein the sensitivity adjusting means electrically changes and adjusts the operation reference position of the operation wire by electric processing in the control device. The function and effect are as follows.

[Action]

According to the first feature, when the relationship between the measured ground height of the ground working device measured by the level sensor by the sensitivity adjusting means and the actual ground height of the ground working device is adjusted, the elevation control is performed. The reference position of the grounding float to be stopped changes, and when this reference position is set on the descending side, the biasing force acting on the grounding float from the spring is reduced to increase the sensitivity, and conversely,
When the reference position is set on the ascending side, the urging force acting on the ground float from the spring is increased to lower the sensitivity.

According to the second feature, by operating the sensitivity setting lever for adjusting the position of the operation wire, the operation reference position is changed, and as a result, the reference position of the ground float for stopping the elevation control is changed. The control sensitivity can be arbitrarily adjusted for the same reason as in the operation (1).

According to the third feature, by operating the sensitivity setting device, the operation reference position is electrically changed, and as a result, the reference position of the ground float for stopping the elevation control is changed. For the same reason, the control sensitivity can be arbitrarily adjusted.

[Advantage of the Invention] Therefore, a paddy working machine that can reasonably set the sensitivity of the elevation control by adjusting the relationship between the measured ground height and the actual ground height has been rationally configured (claim 1). ). Further, the sensitivity can be easily adjusted only by providing a mechanically operated system without specially performing electrical processing (claim 2), and the sensitivity can be easily adjusted by combination with the electrical processing. (Claim 3).

[0013]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a drive-type front wheel 1 and a drive-type rear wheel 2 that are steered.
The engine 4 is mounted on the front part of the traveling body 3 provided with the engine, and the hydrostatic continuously variable transmission H, in which the power from the engine 4 is transmitted to the front part of the traveling body 3, And a rear axle case 6 at a rear position to which power from the transmission case 5 is transmitted, and a steering handle 7 at the center of the traveling body 3. Driver seat 8
A parallel 4 driven and raised and lowered by a lift cylinder 9 as an actuator with respect to the rear end of the traveling machine body 3
A seedling planting device A for 6-row planting as a ground working device is connected via a continuous link mechanism L, and a rice planting machine as a paddy working machine having a fertilizing device B at the rear of the traveling machine body 3 is provided. Constitute.

The transmission case 5 has a differential mechanism (not shown) for transmitting power to the left and right front wheels 1, 1 and an inter-stock shift for setting the number of seedling planting operations of the seedling planting apparatus A per unit traveling distance. A mechanism (not shown) is built in, and a planting clutch C for transmitting and shutting off power from the transmission case 5 to the seedling planting apparatus A is built in.
The rear axle case 6 has a power transmission mechanism (not shown, not provided with a differential mechanism) for transmitting power to the left and right rear wheels 2, and left and right rear wheels 2 from the power transmission mechanism, respectively. The left and right clutch brake mechanisms 10 and 10 for turning off the power transmitted to the vehicle and simultaneously applying the braking force are incorporated.

As shown in FIGS. 1 and 8, a main shift lever 11 for shifting the continuously variable transmission H is disposed on the left side of the meter panel MP in front of the driver's seat. Is provided with a sub-transmission lever 12 for shifting a gear-type sub-transmission (not shown) in the transmission case, and an elevation lever 13 for controlling the elevation of the seedling planting device A is provided on the right side of the driver's seat 8. And a sensitivity adjusting lever 14 for setting the sensitivity when raising and lowering the seedling planting apparatus A by following the field scene S, and disposing a forced lifting lever 15 near the steering handle 7. is there.

As shown in FIGS. 1 and 2, the link mechanism L comprises a pair of left and right top links 17, a pair of left and right lower links 18, and a vertical link 19 at the rear end. The transmission case 20 of the seedling planting apparatus A is rotatably connected to the section. The seedling planting apparatus A includes the transmission case 20 to which power is transmitted from the traveling machine body 3 via the transmission shaft 21, a rectangular pipe-shaped pipe frame 22 in a horizontally long posture connected to the transmission case 20,
Three chain cases 23 whose front ends are connected and fixed to the pipe frame 22 to transmit the power from the transmission case 20 in a branched manner, and a rotary member that rotates around the axis in a lateral posture at the right and left positions at the rear of each chain case 23. It has a case 24, a planting arm 25 attached to the rotary case 24, a seedling mounting table 26 on which a mat-shaped seedling W is placed, and three leveling floats 27 (an example of a ground float). At the time of planting operation, the planting claws 25A of the planting arm 25 cut out the seedlings one by one from the lower end of the mat-shaped seedling W placed on the seedling placing stand 26, and perform the operation of planting in the field scene S. Have been.

As shown in FIGS. 2 to 5, a planting depth adjusting shaft 30 is provided at the rear of the pipe frame 22 in a posture parallel to the pipe frame 22 so as to be rotatable around its axis. The three leveling floats 27 are supported at the rear ends of three sets of arms 31 extending rearward from the depth adjusting shaft 30 so as to be swingable around a support shaft 29 in a laterally oriented posture. By arbitrarily operating the planting depth adjusting lever 32 connected to the adjusting shaft 30 and locking and holding the planting depth adjusting lever 32 on the lever guide 33, the vertical distance of the leveling float 27 with respect to the operating path T of the planting claw 25A can be reduced. Change to field scene S
It is configured so that the planting depth of seedlings can be adjusted. Also, the first link 35 is swingably pivoted around the first support shaft 34 in the lateral posture at the center position in the left-right direction of the front part of the leveling float 27 (hereinafter referred to as sensing float 27S) at the center position in the left-right direction. A second link 37 is supported by the pipe frame 22 at a position corresponding to the second link 37 so as to be swingable around a second support shaft 36 in a lateral posture, and the first link 35 and the second link 37 are bent and extended by a connection shaft 38. A flexure link that guides the operation of the front part of the sensing float 27S in the vertical direction while preventing the sensing float 27S from swinging in the horizontal direction by being freely connected is configured.

Further, a vertical link 40 in a vertical position is swingably movable about an axis 39 in a horizontal position with respect to the upper surface of the sensing float 27S at a position sandwiched between the bending and extending link and the planting depth adjusting lever 32. With the pipe frame 22
Bracket 41 provided in a cantilever shape toward the front with respect to
Swinging link 4 at the front end of
3, and a pin 44 provided at the front end side of the oscillating link 43 in a horizontal position is inserted into a long hole 40 </ b> A drilled in a vertical direction with respect to the vertical link 40, and the vertical link 40 is A tension-type sensing spring 45 is provided between the upper end and the pin 44, and the rear end of the swing link 43 and the planting depth adjusting lever 32 are connected by a correction rod 46. The end of the outer wire 47A of the operation wire 47 is connected and fixed to the upper end of the vertical link 40, and the inner wire 47B of the operation wire 47 is connected to the pin 44. When the front end side of the sensing float 27S is displaced downward (to the side approaching the field scene S) and swings upward with respect to the reference, the distance D between the upper end of the vertical link 40 and the pin 44 is increased, and the inner wire 47B is disconnected. When the pulling operation is performed and the seedling planting device A is displaced upward (side away from the field scene S) with respect to the field scene S and the front end side of the sensing float 27S swings downward, the upper end of the vertical link 40 is Pin 44
The operation direction is set so that the distance D with the inner wire 47B is reduced and the inner wire 47B is relaxed. Further, for example, when the planting depth adjusting lever 32 is operated on the deep planting side (the side on which the operating end of the lever 32 is operated downward in the figure), the front end of the swing link 43 is swung up. Let me float 27
By displacing the position of the pin 44 upward by an amount equal to the lifting amount of S, the value of the distance D is maintained and the sensitivity of the elevation control is maintained.

As shown in FIGS. 1, 5, and 7, the fertilizer applicator B includes a hopper 50 for storing granular or powdered fertilizer, and a feeding mechanism for feeding six fertilizers from the hopper 50. 51, a blower blower 52 driven by a blower motor 52 </ b> M to feed the fertilizer fed from the feeder mechanism 51 by wind pressure, The fertilizer is supplied with fertilizer from the fertilizing hose 53 to the bottom of the field scene S, and is provided with six groovers 54 supported by the leveling float 27. Also, the feeding mechanism 51
Is provided with a feeding roller 51B built in a case 51A, and a fertilizing clutch F provided on a transmission shaft 56 for transmitting the power for rotating the rotation shaft of the feeding roller 51B from the transmission case 5 to the rear axle case 6. The fertilizer is fed out in synchronization with the running speed by transmitting from the vehicle. The fertilizing clutch F operates the switching arm 58 provided in the case 57 to the “ON” position (see FIG. 11) to thereby transfer the power from the transmission shaft 56 to the output shaft 5.
9 by operating the switching arm 58 to the “OFF” position so that power is not transmitted to the output shaft 59 (the transmission system is not described in detail).
The arm 61 </ b> A of the clutch 61 and the arm 61 </ b> A of the clutch 61 are operatively connected to each other via a rod 62 while transmitting power to the rotation shaft of the feeding roll 51 </ b> B.

A control system is configured as shown in FIG. 12, and the control system includes a control device 65 having a microprocessor.
With respect to (an example of the control means), a potentiometer type lever sensor 66 operated by the elevating lever 13 and a potentiometer type level sensor 67 operated by the operation wire 47 to measure the vertical operation amount of the sensor float 27S. A system for inputting signals from the forced lifting switch 68 operated by the forced lifting lever 15 and the upper limit switch 69 for detecting that the link mechanism L has reached the upper limit is formed. A solenoid valve V for supplying and discharging hydraulic oil;
M, a system for outputting a control signal to each of the clutch motors 70 for turning on and off the planting clutch C is formed.

More specifically, as shown in FIGS. 8 to 13, the lever sensor 6 for measuring the operation position of the elevating lever 13 is used.
6, a level sensor 67 for measuring the height of the seedling planting apparatus A with respect to the field via the operation wire 47, and a clutch motor 70 for turning on and off the planting clutch C. Bolt 7 for frame 71
It is detachably connected via 2. As shown in the figure, the bracket G has a lever support portion 74 for supporting the elevating lever 13 welded and fixed to a metal plate bracket body 73, and a support plate 75 for supporting the level sensor 67 and the clutch motor 70. Welding fixed, level sensor 6
7 is formed by bending the bracket body 73 so as to support the pivot shaft 67A.

The flange portion of the lever sensor 66 is screwed to the bracket body 73, the lifting lever 13 is connected to the operating shaft 66A of the lever sensor 66, and a plate-shaped arm plate is attached to the base end of the lever sensor 66. 76 is fixed. A plurality of engagement holes 76A are formed in the arm plate 76 along a trajectory centered on the pivot axis of the elevating lever 13, and a ball 77 engaged with and disengaged from the engagement hole 76A is provided. The lever support 74 has a detent mechanism including a compression spring 78 that urges toward the engagement hole 76A and a case 79 that accommodates the compression spring 78. still,
The lifting / lowering lever 13 is held at the “neutral” position, the “up” position, the “down” position, the “planting” position, and the “automatic” position by the holding function of the detent mechanism. A locking pin 80 is fixed to the moving end.

The sensitivity adjusting lever 14 is swingably supported around the base end 14A with respect to the body frame 71,
In addition, the outer wire 47A of the operation wire 47 is supported by a swinging end of an adjustment arm 85 that swings integrally with the sensitivity adjustment lever 14, and is configured to be freely detachable from a lever guide 84. The flange portion of the level sensor 67 is screwed to a support plate, and a detection arm 86 is connected to an operation shaft 67A of the level sensor 67.
The inner wire 47B of the operation wire 47 is connected to one end of the control wire 6, and a return spring 87 is provided between the other end and the adjustment arm 85.

Further, a flange portion of the clutch motor 70 is screwed to a support plate 75, and an operation arm 88 is fixed to an operation shaft of the clutch motor 70, and is pushed against a locking pin 89 of the operation arm 88. The upper end of a first rod 90 of a pulling operation type is engaged with the other end of the first rod 90. A second rod 94 of a push-pull operation type is inserted into and engaged with the hole 92A, and pushes and pulls this rocking plate 92 and the rocking end of an arm 93 for turning on and off the planting clutch C built in the transmission case 5.
It is linked with. Further, a spring 95 is provided to apply a biasing force to the swinging plate 92 to disengage the planting clutch C, and a push-pull operation type second push-pull operation mechanism is provided between the swinging plate 92 and the switching arm 58 of the fertilizing clutch F. 3 rod 96
Is interposed.

The traveling machine of the rice transplanter is designed to be used in combination with the one in which the planting clutch C is manually turned on and off. The one in which the planting clutch C is turned on and off by this manual operation is shown in FIG. As shown in the figure, a lift lever 13 is swingably supported around a support shaft 101, and a plurality of recesses 102A are formed in an arc portion of a sector plate 102 which swings integrally with the lift lever 13. Engagement arm 104 provided with roller 103 to be fitted at the swing end
Is urged in the engagement direction by a spring 105 and is swingably supported on the body frame 71, whereby the operation position of the elevating lever 13 is determined.
The upper end of the first rod 90 is inserted into and linked to an arc-shaped long hole 102B centered on the support shaft 101 formed in
The lower end of the first rod 90 is connected to the swing plate 92. Those having the same functions as those of the above-described structure are denoted by the same reference numerals and symbols as those of the above-described structure.

Further, this rice transplanter is configured so that when the clutch motor 70 fails, the planting clutch C can be turned on and off by the manual operation force from the elevating lever 13. If the clutch motor 70 fails, FIG. As shown by the phantom line, the locking pin 8 of the operating arm 88 of the clutch motor 70
9, the upper end of the first rod 90 connected to the first rod 9 is separated.
The upper end of the rod 90 is fixed to the locking pin 80 of the arm plate 76.
When the lifting arm 13 is operated to the "planting" position, the planting clutch C is engaged and when the lifting arm 13 is operated to a position outside the "planting" position, the planting clutch C is disengaged. In addition, the cutting state is maintained.

The control device 65 shown in FIG. 12 has a program set to perform the following control. That is, when it is determined that the lifting lever 13 has been operated to the "up" position based on the signal from the lever sensor 66, the solenoid valve V controls the pressurized oil to the lift cylinder 9 to start the seedling planting apparatus A. Control to raise, and conversely,
When it is determined that the elevating lever 13 has been operated to the "down" position, the hydraulic oil is discharged from the lift cylinder 9 under the control of the solenoid valve V to lower the seedling planting apparatus A.
When the signal from 7 reaches a preset target signal range, the descending control is stopped, and when the signal from the level sensor 67 deviates from the preset target signal range,
Automatic raising and lowering control for raising and lowering the seedling planting apparatus A is performed so that the signal from the level sensor 67 converges to the target signal area. The target signal area is set in advance in an area having a constant width on the ascending control side and the descending control side based on the target signal value. When the target signal value is detected by the level sensor 67, the sensing float is set. 27S vertical link 40
The distance D between the upper end of the sensor 44 and the pin 44 becomes a determined value, and the attitude of the sensing float 27S is also determined. The value of the distance D is changed by operating the sensitivity adjusting lever 14. When the sensitivity adjusting lever 14 is operated in the "sensitive" direction, the value of the distance D decreases, and the sensing spring 45
From above, the urging force acting on the sensing float 27 decreases, and the sensing float 27S can sensitively detect the level change of the field scene S. When the sensitivity adjusting lever 14 is operated in the direction of "dull", the value of the distance D is reduced. As a result, the urging force acting on the sensing float from the sensing spring 45 increases, so that it becomes difficult for the sensing float 27S to catch the level change in the field scene.

The control device 65 is provided with the lever sensor 66.
When it is determined that the lift lever 13 has been set to the "planting" position based on the signal from the CPU, the clutch motor 70 is operated and the blower motor 52M is operated while maintaining the above-described automatic lift control. The operation arm 88 is operated by the operation of the clutch motor 70.
Of the planting clutch C through the first rod 90, the swinging plate 92, and the second rod 94, respectively.
To start the operation of the seedling planting apparatus A by operating the planting clutch C to the entry position, and also to transmit the operating force from the swinging plate 92 to the switching arm 58 of the fertilizing clutch F to release the fertilizing clutch F. The entry operation is performed to start feeding the fertilizer of the fertilizer application device B.

When the control device 65 determines that the raising / lowering lever 13 has been set to the "neutral" position based on a signal from the lever sensor 66 when the seedling planting device A moves up and down,
When the solenoid valve V is set to the neutral position and control for stopping the elevation control is performed, and when it is determined that the elevation lever 13 is set to the “automatic” position, the automatic elevation control is performed and the forced elevation switch 68 When it is determined that the forcible raising / lowering lever 15 has been operated to the ascending position U based on the above signal, the solenoid valve V is controlled to perform the ascending control of the seedling planting device A until the upper limit switch 68 detects it. When it is determined that the forcible elevating lever 15 has been operated to the lowering position DW in this ascending state, control is performed to control the solenoid valve V to lower the seedling planting apparatus A and return to the automatic elevating control. . The forcible lifting lever 15 is held at the neutral position N in a non-operating state, and is biased by a spring so as to return to the neutral position N by releasing the operating force after operating the raised position U and the lowered position DW.

As described above, in the present invention, the sensing float 27
The level of the field of the seedling planting device A measured in S with respect to the field is measured by an operation wire 27 to a level sensor 67 provided in the traveling machine 3
The control system is configured to operate the electromagnetic valve V based on the measurement result of the level sensor 67 so as to move up and down the seedling planting device A, for example, to the sensing float 27S. As in the case where the level sensor is provided, it is possible not only to reliably avoid inconveniences such as operation failure due to mud adhering to the level sensor and occurrence of an electric short circuit to make detection impossible. This eliminates the need for a special structure that enhances performance and sealing performance, and without changing the processing of controlling the solenoid valve V so that the detection result of the level sensor 67 falls within a predetermined value range. When the sensitivity adjustment lever 14 is operated only by providing a structure for adjusting the position of the outer wire 27A of the operation wire 27 by operating the sensitivity adjustment lever 14, Has become one that easily set the sensitivity of the elevator control of the elevator control biasing force becomes that changes acting in the direction down on the sensing float 45S from the sensing spring 45 target attitude is changed knowledge float 27S.

[Other Embodiments] The present invention is not limited to the above-described embodiment.
And a potentiometer-type sensitivity setting device 108 (an example of sensitivity adjustment means) operated by a dial 107 as shown in FIG.
It is also possible to arbitrarily set the target swing posture of the sensing float 27S around the support shaft 29 to adjust the elevation control sensitivity. Further, when the sensitivity adjustment dial 107 is operated to the "sensitive" side, the operation reference position measured by the level sensor 67, that is, the attitude (target attitude) of the sensing float 27S for stopping the raising / lowering control of the seedling planting apparatus A is stopped. As a result of the process of changing to the front lower side, the inner wire 47
The lifting control is stopped in a state where B is sent to the level sensor 67 side, the downward urging force acting on the sensing float 27S from the sensing spring 45 is reduced, and the subtle level change of the field scene S is sensed well. Gain. On the contrary,
When the sensitivity setting dial 107 is operated to the "dull" side, the operation reference position measured by the level sensor 67, that is, the posture (target posture) of the sensing float 27S for stopping the raising / lowering control of the seedling planting apparatus A is raised forward. As a result, the lifting control is stopped in a state where the inner wire 47B is pulled out from the level sensor 67 side, the downward biasing force acting on the sensing float 27S from the sensing spring 45 is increased, and the Lifting control can be performed without being affected by small irregularities.

[Brief description of the drawings]

FIG. 1 is an overall side view of a rice transplanter.

FIG. 2 is a side view of the seedling planting apparatus.

FIG. 3 is a side view showing the structure of a level measurement system of the seedling planting apparatus.

FIG. 4 is a front view showing the structure of a level measurement system of the seedling planting apparatus.

FIG. 5 is a plan view showing the structure of a level measurement system of the seedling planting apparatus.

FIG. 6 is a rear view of the fertilizer application device.

FIG. 7 is a longitudinal sectional side view of a hopper portion of the fertilizer application device.

FIG. 8 is a side view showing an arrangement of a lifting lever and a sensitivity adjustment lever.

FIG. 9 is a side view and a longitudinal side view showing an arrangement of a lever sensor, a clutch motor, and the like.

FIG. 10 is a plan view showing an arrangement of a lever sensor, a level sensor, and a clutch motor.

FIG. 11 is a schematic diagram of an operation system for the planting clutch and the fertilizing clutch.

FIG. 12 is a block circuit diagram of a control system.

FIG. 13 is a side view showing a configuration for manually operating the planting clutch.

FIG. 14 is a block circuit diagram of a control system according to another embodiment;

[Explanation of symbols]

 3 Traveling body 9 Actuator 14 Sensitivity adjusting lever 27 Ground float 45 Spring 47 Operating wire 47A Outer wire 47B Inner wire 65 Control device 67 Level sensor 108 Sensitivity setting device A Ground work device S Field scene V Control valve

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2B062 AA05 AB01 BA62 CA03 CA05 CA06 2B063 AA10 AB01 BB09 BB22 BB44 CA04 CA10 CA16 CB11 2B304 KA08 LA02 LA09 LB05 LB16 LC04 MA05 MB02 MC08 MD04 PA01 PA11 PC08 PD19 QA11 QA22 QA13

Claims (3)

[Claims] A hydraulic actuator for driving and lowering a ground working device provided on a traveling body so as to be movable up and down, a control valve for supplying and discharging hydraulic oil to and from the actuator, and a spring for the ground working device. An operation wire for taking out the relative height between the field scene and the ground work device based on the displacement of the ground float provided in a state of being biased downward, and a relative height of the ground work device taken out with this operation wire. A paddy working machine comprising control means for operating the control valve based on a field scene to raise and lower the ground working device, wherein the control valve is configured by an electromagnetic valve, and the control means is A level sensor provided on the traveling body to electrically measure the operation amount of the inner wire of the operation wire, and control for outputting a signal for controlling the control valve based on a signal from the level sensor Is composed of a location, and the measured ground height of the ground work apparatus to be measured by the level sensor via the operation wire, the actual ground level with paddy working machine is provided with a sensitivity adjusting means for adjusting the relationship of the ground working device. 2. The sensitivity adjusting means according to claim 1, wherein said sensitivity adjusting means comprises a sensitivity adjusting lever for mechanically changing and adjusting an operation reference position of the operating wire by adjusting a position of an outer wire of the operating wire on the traveling body side of the operating wire. Paddy working machine. 3. The paddy working machine according to claim 1, wherein said sensitivity adjusting means comprises a sensitivity setting device for electrically changing and adjusting an operation reference position of an operation wire by electric processing in said control device.