JPH08228533A - Ground working device position changing structure for paddy field operation vehicle - Google Patents

Abstract

PURPOSE: To provide the subject structure for preventing hunting phenomena by lifting and lowering control, by installing a height sensor for detecting height from the face of a field to a ground working device. CONSTITUTION: This ground working device position changing structure for a working vehicle is equipped with a height sensor 16 for grounding and following the face of a paddy field G while vertically locking the front part side around the lateral shaft center at the rear part side and for detecting height from the face of the paddy field G to a ground working device 3 by the vertical angle from the ground working device 3 and a longitudinal inclination sensor 14 for detecting a longitudinal inclination angle of the ground working device 3 from a horizontal plane. The ground working device position changing structure for the working vehicle is further furnished with a lifting and lowering control means for operating and handling an actuator 5 so as to maintain the ground working device 3 at a set height from the face of the field G based on the detected value of the height sensor 16 and a sensitivity adjusting means for changing a control sensitivity in the lifting and lowering control means to an insensible side when a machine body becomes an attitude to drop forward from the horizontal plane based on the detected value of the longitudinal inclination sensor 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paddy field working vehicle in which a ground working device such as a seedling planting device or a direct seeding device such as a riding type rice transplanter or a riding type direct seeding device is connected to a machine body so as to be vertically movable. , A posture changing structure of a ground work device.

[0002]

2. Description of the Related Art In a riding type rice transplanter, which is an example of a paddy field work vehicle as described above, a seedling planting device (corresponding to a ground working device) is vertically movably connected to the rear part of the body so that the seedling planting device can be installed. It has an actuator that moves up and down with respect to the machine body.
In this case, a height sensor that detects the height from the rice field to the seedling planting device (the front side oscillates up and down around the horizontal axis on the rear side, and follows the ground contact with the rice field to determine the vertical angle with respect to the seedling planting device). The height of the seedling planting device from the paddy field is detected by the actuator, so that the seedling planting device is maintained at the set height from the paddy field based on the detection value of the height sensor. Elevating control means for raising and lowering the planting device is provided. As a result, the seedling planting device is maintained at the set height from the paddy field, and the seedling planting device is planting the seedlings at a predetermined planting depth.

[0003]

As planting work progresses in a riding-type rice transplanter, the front and rear wheels of the machine touch the ground, and the unevenness of the tiller causes the machine to move up and down. It becomes. As a result, the front side swings up and down around the horizontal axis on the rear side to follow the ground contact with the paddy field as described above, and the height from the paddy field to the seedling planting equipment is detected by the vertical angle with respect to the seedling planting equipment. With the height sensor, the height sensor also has a front-lowering posture (rear-raising posture) when the aircraft is in a front-lowering posture.

As described above, if the height sensor is in the front-lowering posture, the front part of the height sensor is in contact with the rice field surface, and the height sensor sensitively reacts to the unevenness of the rice field surface and swings up and down. Therefore, if the unevenness of the rice field is severe, the lifting control means may cause a hunting phenomenon, resulting in floating seedlings or extremely deeply planted seedlings. In this case, if the aircraft is in the front-lowering posture, the operator may change the control sensitivity of the lifting control means to the insensitive side by the changeover switch, but since the operator concentrates on the operation of the aircraft, There is a case where the planting work is performed with the inappropriate control sensitivity without changing the control sensitivity of the elevating control means to the insensitive side without noticing the front-lowering posture.
According to the present invention, in a paddy work vehicle in which a ground work device is connected to a machine body so that the machine can be vertically moved, even if the control sensitivity of the lifting control means is not appropriate due to a change in the posture of the machine body, the work is performed as it is. The purpose is to prevent the situation.

[0005]

The feature of the present invention resides in that the structure for changing the posture of the ground work device for a paddy work vehicle as described above is configured as follows. [1] A ground work device is movably connected to the machine body and equipped with an actuator that moves the ground work device up and down with respect to the machine body. The front side oscillates up and down around the horizontal axis on the rear side and touches the rice field. Following this, a height sensor that detects the height from the rice field to the ground work device by the vertical angle with respect to the ground work device and a front-back tilt sensor that detects the front-back tilt angle of the aircraft with respect to the horizontal plane, and the height sensor Based on the detected value, the ground work equipment is maintained at the set height from the rice field. In this case, it is provided with sensitivity adjusting means for changing the control sensitivity of the elevation control means to the insensitive side.

[2] A ground work device is connected to the machine body so as to be vertically movable and rolling, and a first actuator for vertically moving the ground work device with respect to the machine body and a second actuator for rolling the ground work device with respect to the machine body. An actuator,
The front side swings up and down around the horizontal axis on the rear side and follows the ground contact with the field surface, and the height sensor that detects the height from the field surface to the ground device by the vertical angle with respect to the ground working device, and the horizontal plane or the field surface. A left and right tilt sensor that electrically detects the left and right tilt angle of the ground work device with respect to, and a tilt angle indexing unit that calculates the tilt angle between the front and rear of the aircraft with respect to the horizontal plane from the detection value of the left and right tilt sensor, and the height sensor Based on the detected value, the ground work device is maintained at the set height from the rice field, and the elevating control means for operating and operating the first actuator, and the ground work device on the horizontal surface or the rice field based on the detection value of the right and left tilt sensor. On the other hand, based on the tilt angle by the rolling control means for operating the second actuator and the tilt angle indexing means so as to be maintained in parallel in the left-right direction. When the aircraft is forward descending position with respect to the horizontal plane, it is provided with a sensitivity adjusting means for changing the control sensitivity of the elevation control means insensitive side.

[0007]

[Action]

[I] With the configuration as described in [1] above, the ground work device is automatically operated by the actuator and the elevating control means so that the ground work device is maintained at the set height from the field based on the detection value of the height sensor. It is operated up and down. At the same time, the front-back inclination sensor detects the front-back inclination angle of the aircraft with respect to the horizontal plane, and when the aircraft takes a front-lowering posture with respect to the horizontal plane, for example, the height sensor 16 as shown in FIG. It is determined that the front part of the height sensor 16 (on the left side of the paper surface) is in contact with the rice field, and the height sensor 16 sensitively reacts to the unevenness of the rice field and swings up and down.

In such a state, it is expected that the lifting control means that operates based on the detection value of the height sensor will cause a hunting phenomenon. The control sensitivity of the means is automatically changed to the insensitive side, and the hunting phenomenon of the elevation control means is prevented in advance.

[II] In a paddy work vehicle, a ground work device is connected to the machine body so as to be vertically movable and rolling, and a first actuator for vertically moving the ground work device with respect to the machine body and the ground work device are provided to the machine body. Some have a second actuator for rolling operation. In the case of the configuration of the above [2], the same height sensor as that of the configuration of the above [1] and a horizontal inclination sensor that electrically detects the horizontal inclination angle of the ground work device with respect to the horizontal plane or the rice field are provided. With this, when configured as in the above item [2], the ground work device is controlled by the first actuator and the lifting control means so that the ground work device is maintained at the set height from the field based on the detection value of the height sensor. The ground actuator is automatically rolled by the second actuator and the rolling control means so that the ground actuator is automatically moved up and down so that the ground actuator is maintained parallel to the horizontal surface or the rice field based on the detection value of the right and left tilt sensor. Operated.

As described above, the left / right tilt sensor that outputs an electrical detection value is affected not only by the left / right tilt of the ground work device but also by the front / back tilt of the ground work device. Does not only include the left and right tilt angles of the ground work device with respect to the horizontal plane, but also includes the front and rear tilt angles of the ground work device with respect to the horizontal plane. With this, it is possible to experimentally determine the front-back inclination angle of the ground work device with respect to the horizontal plane from the detection value of the left-right inclination sensor, and obtain the front-back inclination angle of the aircraft with respect to the horizontal plane from the calculated inclination angle. You can

Therefore, if the above-mentioned [2] is constructed,
The front and rear tilt angles of the machine body with respect to the horizontal plane are calculated from the detection values of the left and right tilt sensors, and when the machine body is in the front-lowering posture with respect to the horizontal plane as in the case of the configuration of the above [1], the control of the lifting control means is performed. The sensitivity is automatically changed to the insensitive side, and the hunting phenomenon of the lifting control means is prevented in advance. In this case, since the detection value of the left / right tilt sensor of the rolling control means, which may be called an existing configuration, is used, a dedicated sensor or the like for detecting the tilt angle of the front and rear of the body with respect to the horizontal plane is not necessary.

[0012]

According to the first aspect of the present invention, in the paddy work vehicle in which the ground work device is connected to the machine body so as to be able to move up and down, the control sensitivity of the elevating control means particularly when the machine body is in the front-lowering posture. It was possible to prevent the hunting phenomenon of the ascending / descending control means by automatically changing to the insensitive side. This prevents work problems (occurrence of floating seedlings and extremely deeply planted seedlings during seedling planting work) due to the hunting phenomenon of the lifting control means, and improves the work performance of paddy field work vehicles. I was able to improve. Since the control sensitivity of the lifting control means is automatically changed to the insensitive side, the operability is also improved.

According to the second aspect of the invention, in the work vehicle in which the ground work device is connected to the machine body so as to be capable of raising and lowering operations and rolling operation, particularly when the machine body is in the front-lowering posture, the control of the lifting control means is performed. By automatically changing the sensitivity to the insensitive side, the hunting phenomenon of the lifting control means could be prevented. This prevents work problems (occurrence of floating seedlings and extremely deeply planted seedlings during seedling planting work) due to the hunting phenomenon of the lifting control means, and improves the work performance of paddy field work vehicles. I was able to improve. And since the control sensitivity of the lifting control means is automatically changed to the insensitive side, the operability is also good, and by using the detection value of the left and right tilt sensor of the existing rolling control means, Since a dedicated sensor for detecting the tilt angle of the front and rear of the machine body with respect to the horizontal plane is not necessary, it is also advantageous in terms of reduction of production cost.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. (1) As shown in FIG. 1, a link mechanism 4 is liftably supported at a rear portion of a machine body supported by front wheels 1 and rear wheels 2, and is freely rotatable around a front-rear axis P2 at a rear end of the link mechanism 4. The seedling planting device 3 (corresponding to the ground work device) is connected to form a riding-type rice transplanter that is an example of a paddy field work vehicle. A hydraulic cylinder 5 (corresponding to an actuator and a first actuator) for moving the link mechanism 4 up and down is provided, and a drive mechanism 13 (a second actuator) for rolling the seedling planting device 3 around the front-rear axis P2 with respect to the link mechanism 4. (Corresponding to) is connected across the rear part of the link mechanism 4 and the back surface of the seedling planting device 3.

The seedling planting device 3 rotatably supports a planting case 8 having a pair of planting claws 7 on the rear part of the support case 6, and reciprocates a seedling stand 9 to the left and right with respect to the support case 6. The pair of planting claws 7 alternately take out the seedlings from the seedling stand 9 and plant them on the rice field G as the planting case 8 rotates.

As shown in FIGS. 2 and 1, the seedling planting device 3
One sensor float 16 (corresponding to a height sensor) is arranged at the center of the left and right of the sensor float, and a pair of side floats 25 is arranged on both left and right sides of the sensor float 16. The sensor float 16 has a rear side supporting the support case 6. The arm 17 is swingably supported around a horizontal axis P1, and the front side of the sensor float 16 swings up and down to follow the ground surface G to follow the ground. As shown in FIGS. 2 and 3, a balance-shaped first arm 26 and a second arm 27 are vertically swingably supported by a frame 18 fixed to the front end of the support case 6, and the first and second arms 26 are supported. , 27 support a bracket 28 having an L-shape in plan view, and the first and second arms 26, 27 support the bracket 28 so that the bracket 28 can move up and down in parallel.

The potentiometer 19 is fixed to the bracket 28, and the detection arm 1 of the potentiometer 19 is fixed.
9a and the front part of the sensor float 16 are connected by a rod 20. The rod 23 supported on the front part of the sensor float 16 is vertically movably inserted into a bracket 24 fixed to a bracket 28.
A spring 21 that urges the sensor float 16 downward is provided between the bracket and the bracket 24.

(2) Next, the elevation control means and rolling control means of the seedling planting device 3 in the riding type rice transplanter will be described. As shown in FIG. 4, the detection value from the potentiometer 19 of the sensor float 16 is input to the control device 10, and a dial type sensitivity setting switch 11 capable of artificially setting the control sensitivity of the lifting control means is provided. Has been.

With the structure described above, when the sensor float 16 follows the paddy field G along with the planting run, the detected value becomes the target value C based on the detected value from the potentiometer 19 (potentiometer 19 Control unit 1 so that the detection arm 19a of the
When the control valve 12 is operated by 0, the hydraulic cylinder 5 is expanded and contracted, and the seedling planting device 3 is automatically moved up and down. As a result, the seedling planting device 3 is automatically maintained at the set height from the paddy field G, and the seedling planting depth is maintained at the set value (corresponding to the elevating control means).

As shown in FIGS. 2 and 3, a planting depth adjusting lever 29 is fixed to the base of the support arm 17 of the sensor float 16. As a result, the adjustment lever 29
Is operated up and down to engage and fix the lever guide 30,
The vertical angle of the support arm 17 (positions of the horizontal axis P1 and the sensor float 16 with respect to the seedling planting device 3) is changed up and down, and the setting of the seedling planting device 3 to be maintained with respect to the field G (sensor float 16). The height is changed up and down, and the planting depth of seedlings is changed.

In this case, as shown in FIG.
The other end of the first arm 26 is engaged with the pin 29a of 9 and even if the planting depth of the seedling is changed by the adjusting lever 29,
Along with this, the first arm 26 and the bracket 28 are vertically swung. As a result, the vertical distance between the sensor float 16, the potentiometer 19, the rod 23, etc. is maintained at the vertical distance shown in FIG. 2 regardless of the change in the planting depth of the seedlings. There is no change in the target value C.

As shown in FIGS. 1 and 4, a horizontal inclination sensor 15 for electrically detecting the horizontal inclination angle of the seedling planting device 3 with respect to a horizontal plane is arranged on the back surface of the seedling stand 9 as shown in FIGS. The detection value of the left and right inclination sensor 15 is input to the control device 10. Thus, the drive mechanism 1 is controlled by the control device 10 based on the detection value of the left and right tilt sensor 15.
3 is operated and the drive mechanism 13 drives the seedling planting device 3
Is automatically rolled so that it becomes horizontal in the left-right direction (corresponding to rolling control means).

(3) Next, the setting of the control sensitivity of the elevation control means of the seedling planting device 3 in the riding type rice transplanter will be described. In the raising / lowering control means of the seedling planting device 3 as described above, when there are many irregularities on the rice field G, the sensitivity setting switch 11
To the insensitive side. In this case, the target value C shown in FIG.
Is changed to the upward side according to the operation position of the sensitivity setting switch 11.

As a result, the seedling planting device 3 is automatically operated so that the detection value from the potentiometer 19 becomes the upward target value C (so that the detection arm 19a of the potentiometer 19 is in the posture of the upward target value C). Is vertically operated. Sensor float 1 at this upward target value C
Since the posture of 6 is higher than that shown in FIG. 2, the contact area of the sensor float 16 with the rice field G is reduced, the spring 21 is compressed, and the biasing force of the spring 21 is strengthened. Therefore, the ground follow-up sensitivity of the sensor float 16 to the rice field G, that is, the control sensitivity of the ascending / descending control means is changed to the insensitive side.

On the contrary, when the unevenness of the rice field G is small, the sensitivity setting switch 11 is operated to the sensitive side. In this case, FIG.
The target value C indicated by is changed to the downward side corresponding to the operation position of the sensitivity setting switch 11. As a result, the seedling planting device 3 automatically moves up and down so that the detection value from the potentiometer 19 becomes the downward target value C (so that the detection arm 19a of the potentiometer 19 is in the downward target value C posture). Operated. Since the attitude of the sensor float 16 at the downward target value C is lower than that shown in FIG. 2, the contact area of the sensor float 16 with the rice field G increases, and the spring 21 expands to urge the spring 21. Is weakened. Therefore, the field G of the sensor float 16
The sensitivity to ground contact with the ground, that is, the control sensitivity of the elevation control means is changed to the sensitive side.

(4) Next, the automatic correction of the control sensitivity (target value C) preset by the sensitivity setting switch 11 in the elevation control means will be described with reference to FIGS. 5 and 6. As shown in FIGS. 4 and 1, the speed sensor 22 that detects the traveling speed of the airframe by detecting the number of rotations of a transmission shaft (not shown) to the rear wheels 2, and the tilt angle of the airframe front and rear with respect to the horizontal plane are shown. The front-back inclination sensor 14 for detecting is provided, and the speed sensor 22 and the front-back inclination sensor 14 are provided.
The detected value of is input to the control device 10.

The control sensitivity (target value C) is arbitrarily set by the sensitivity setting switch 11, and the raising / lowering operation of the seedling planting device 3 based on the detection value of the potentiometer 19 is being performed, and the left / right inclination sensor 15 is operated. In the state where the rolling operation of the seedling planting device 3 is performed based on the detected value, the accumulated value A is cleared, the accumulation of the change in the detected value of the left and right inclination sensor 15 is started, and the accumulated value A Is started to be integrated (step S1), and counting of the first set time T1 and the second set time T2 is simultaneously started (step S2).

It is the first time since the integration is started in step S1.
When the set time T1 has passed (step S3), the current integrated value A after the first set time T1 has passed is compared with the first set value B1 (step S4). In this case, when the current integrated value A after the first set time T1 has passed is smaller than the first set value B1, the detection value of the left and right inclination sensor 15 does not change so much, and the seedling planting device 3 as a whole. It is determined that the sensor float 16 and the side float 25 are sinking into the rice field G, and the speed sensor 22 and the front-rear tilt sensor 14 cause the current traveling speed of the aircraft after the first set time T1 has elapsed, And the tilt angles of the front and rear of the machine body with respect to the horizontal plane are detected (steps S5 and S6).

In the above-mentioned state, if the machine body is in the forward descending posture or the horizontal posture, the speed correction value E is changed from the current target value C.
Is subtracted (target value C-speed correction value E) is newly set as the target value C (step S7), and the attitude correction value D is changed from the current target value C if the aircraft is in the forward rising attitude. The value obtained by subtracting the speed correction value E (target value C-posture correction value D + speed correction value E) is newly set as the target value C (step S8).

The attitude correction value D is set in accordance with the tilt angle of the front and rear of the machine body with respect to the horizontal plane, and becomes larger as the machine body is in the frontward rising attitude (the machine body is in the front lowering attitude) with the horizontal attitude being zero. Is set to.
The speed correction value E is also set according to the operation position of the sensitivity setting switch 11 and the traveling speed of the aircraft shown in FIG. 4, and the larger the operation position of the sensitivity setting switch 11 is on the insensitive side, the greater the traveling speed of the aircraft. Is set so as to increase, and the posture correction value D is set to be larger than the speed correction value E.

As a result, when the sensor float 16 and the side float 25 tend to sink into the paddy field G, and the aircraft is in the front-lowering posture or horizontal posture (step S
7) As the traveling speed of the machine body increases, the target value C is changed to the downward side (the sensitive side of the control sensitivity of the elevation control means).
On the contrary, when the sensor float 16 and the side float 25 tend to sink into the rice field G and the aircraft is in the forward rising posture (step S8), the difference between the posture correction value D and the speed correction value E (from the speed correction value E Also, the target value C is changed to the downward side (the sensitive side of the control sensitivity of the elevation control means) by the posture correction value D being larger. When the current integrated value A after the first set time T1 has passed is larger than the first set value B1 (step S4), it is determined that the normal state is reached and the target value C is not changed.

Next, when the second set time T2 has elapsed since the integration was started in step S1 (step S9), the current integrated value A and the second set value B2 (first set time T2) have elapsed. (Larger than the set value B1) is compared (step S10). In this case, when the current integrated value A after the second set time T2 has passed is larger than the second set value B2, the detection value of the left / right tilt sensor 15 changes drastically and the seedling planting device 3 rises as a whole. It is determined that the sensor float 16 and the side float 25 are floating from the rice field G, and the speed sensor 22 and the front-rear tilt sensor 14 determine the current traveling speed of the aircraft after the second set time T2 has elapsed and the aircraft relative to the horizontal plane. The front and rear inclination angles are detected (steps S11 and S12).

In the above-mentioned state, if the body is in the forward descending attitude, the value obtained by adding the attitude correction value D and the speed correction value E to the current target value C (target value C + posture correction value D + speed correction value E) , Is newly set as the target value C (step S13), and if the body is in the forward rising posture or the horizontal posture,
A value obtained by adding the speed correction value E to the current target value C (target value C + speed correction value E) is newly set as the target value C (step S14).

As a result, when the sensor float 16 and the side float 25 are slightly floating from the rice field G and the vehicle body is in the front-lowering posture (step S13), the more the vehicle body is in the front-lowering posture and the higher the traveling speed of the aircraft is. The target value C is changed to the upward side (the side where the control sensitivity of the ascending / descending control means is insensitive) (corresponding to the sensitivity adjusting means). On the contrary, when the sensor float 16 and the side float 25 are slightly floating above the rice field G and the aircraft is in the forward rising posture or the horizontal posture (step S14), the higher the traveling speed of the aircraft is, the higher the target value C is toward the upward side (up and down). It is changed to the insensitive side of the control sensitivity of the control means). Current integrated value A after the second set time T2 has elapsed
Is smaller than the second set value B2 (step S10),
The target value C is not changed because it is determined to be in a normal state.

As described above, one correction cycle of the control sensitivity (target value C) of the ascending / descending control means is ended, and when this one correction cycle is ended, the detection value of the left / right tilt sensor 15 is ended. The integrated value A of the change is cleared (step S15), the process returns to step S1, and the next correction cycle is started.

[Other Embodiments] As in the above-described embodiments, the horizontal inclination sensor 15 that electrically detects the left and right inclination angles of the seedling planting device 3 with respect to the horizontal plane by the hanging type is the seedling planting device 3
Not only the left and right inclinations of the seedling planting apparatus 3 but also the front and rear inclinations of the seedling planting apparatus 3 are affected, so the detection value of the left and right inclination sensor 15 does not include only the left and right inclination angles of the seedling planting apparatus 3 with respect to the horizontal plane. Without seedling planting device 3 on a horizontal surface
It also includes the angle of inclination before and after. Therefore, it is possible to experimentally determine the front and rear inclination angles of the seedling planting device 3 with respect to the horizontal plane from the detection values of the left and right inclination sensor 15, and the front and rear inclination angles of the aircraft with respect to the horizontal plane can be determined from the calculated inclination angles. You can ask. This allows
The front-back inclination sensor 14 shown in FIGS. 1 and 4 is abolished, and the front-back inclination angle of the fuselage with respect to the horizontal plane is calculated from the detection value of the left-right inclination sensor 15 (corresponding to inclination-angle indexing means), and this is shown in FIGS. It may be configured to be used in steps S6 and S12.

In the above-mentioned embodiment, the target value C is changed in steps S7, S8, S13 and S14 of FIGS. 5 and 6, but the target value C is changed to the target value C without being changed. It may be configured such that the width of the dead zone to be set is changed (a wide side of the dead zone is on the insensitive side and a narrow side is on the sensitive side).

A lateral inclination sensor 1 for detecting the lateral inclination angle of the seedling planting device 3 with respect to the horizontal plane shown in FIGS. 1 and 4.
Instead of 5, a left / right inclination sensor (not shown) that detects the left / right inclination angle of the seedling planting device 3 with respect to the rice field G may be equipped. When equipped with such a left and right tilt sensor,
The drive mechanism 13 is operated by the control device 10 based on the detection value of the left and right tilt sensor, and the drive mechanism 13 automatically performs the rolling operation so that the seedling planting device 3 is parallel to the rice field G in the horizontal direction.

The front-rear tilt sensor 14 shown in FIGS.
When equipped with, the detection value of the front-back inclination sensor 14 can be used not only for changing the target value C in the elevation control means but also as follows. In FIG. 1, the link mechanism 4
The upper link portion is configured to be extendable and retractable, and the upper link portion is extended and retracted to change the posture of the seedling planting device 3 with respect to the machine body in the front-rear direction. This allows
In addition to the automatic raising / lowering operation and rolling operation of the seedling planting device 3, the seedling planting device 3 is maintained horizontally in the front-rear direction by the detection value of the front-back inclination sensor 14. INDUSTRIAL APPLICABILITY The present invention can be applied not only to a riding type rice transplanter, but also to a riding type direct seeding machine in which a direct seeding device (corresponding to a ground work device) is connected to a rear part of the machine body so that it can be freely moved up and down and rolled.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

[Fig. 1] Overall side view of the riding rice transplanter

FIG. 2 is a side view around the sensor float and the potentiometer.

FIG. 3 is a front view of the vicinity of a sensor float and a potentiometer.

FIG. 4 is a diagram showing a linked state of a sensitivity setting switch, a sensor float, a potentiometer, a control valve, and the like.

FIG. 5 is a diagram showing the first half of the flow of changing the control sensitivity (target value C) of the lifting control means.

FIG. 6 is a diagram showing the latter half of the flow of changing the control sensitivity (target value C) of the lifting control means.

[Explanation of symbols]

 3 Ground work device 5 Actuator, 1st actuator 13 2nd actuator 14 Front and rear inclination sensor 15 Left and right inclination sensor 16 Height sensor G Taba P1 Horizontal axis

Claims (2)

[Claims] 1. An actuator (5) for connecting a ground work device (3) to a machine body so that the work machine (3) can be moved up and down with respect to the machine body, and a horizontal axis core (on the rear side) P1) The front side oscillates vertically while following the ground contact with the field (G), and the ground work device (3)
Height sensor (16) for detecting the height from the surface (G) to the ground working device (3) by the vertical angle with respect to
And a front-back inclination sensor (14) for detecting the front-back inclination angle of the body with respect to the horizontal plane, and the ground working device (3) is moved from the field (G) based on the detection value of the height sensor (16). Ascending / descending control means for actuating and operating the actuator (5) so as to maintain the set height, and the ascending / descending movement when the machine body is in a front-lowering posture with respect to a horizontal plane based on the detection value of the longitudinal inclination sensor (14). A structure for changing the posture of a ground work device for a paddy field vehicle, comprising: sensitivity adjusting means for changing the control sensitivity of the control means to the insensitive side. 2. A first actuator (5) for connecting a ground work device (3) to a machine body so as to be able to move up and down and to roll, and to vertically move the ground work device (3) with respect to the machine body.
And a second actuator (13) for rolling the ground working device (3) with respect to the airframe, and a front side swinging up and down around the rear side horizontal axis (P1) and grounding to the rice field (G) Following it, the ground work device (3)
Height sensor (16) for detecting the height from the surface (G) to the ground working device (3) by the vertical angle with respect to
And the ground working device (3) for a horizontal surface or a rice field (G)
A left and right tilt sensor (15) for electrically detecting the left and right tilt angle of the vehicle, and a tilt angle indexing means for calculating the front and back tilt angle of the body with respect to the horizontal plane from the detection value of the left and right tilt sensor (15). Lifting control means for operating the first actuator (5) so that the ground work device (3) is maintained at a set height from the rice field (G) based on the detection value of the height sensor (16). The second actuator (13) is operated so that the ground work device (3) is maintained in parallel to the horizontal plane or the rice field (G) in the left-right direction based on the detection value of the left-right inclination sensor (15). When the vehicle body is in a forward descending posture with respect to a horizontal plane based on the rolling control means to be operated and the tilt angle by the tilt angle indexing means, the control sensitivity in the lifting control means is set to the insensitive side. Ground work apparatus position changing structure of paddy work vehicle that is provided with a further sensitivity adjusting means.