JPH0665252B2 - Attitude control device of rice transplanter - Google Patents

Description

The present invention relates to the structure of an apparatus for controlling the attitude of a rice transplanter machine body.

[Conventional technology]

2. Description of the Related Art Conventionally, when a rice planting operation is performed while traveling on a field scene, the rice transplanter proceeds while the left and right wheels of the rice transplanter are always in contact with the tiller while the rice field is traveling in the field. When the cultivators with both right and left wheels touching down all at once, the difference between the machine and the field scene is reduced, and the depth of seedling planting in the field scene by the seedling planting device becomes too deep. The robot is moved downward to raise the aircraft to the field scene to control the seedling planting depth.

Further, if the tiller is uneven or inclined with respect to the left and right sides of the traveling direction of the machine body, the machine body also remains tilted left and right unless the heights of the left and right wheels are changed.

In order to prevent such inconvenience, for example, Japanese Patent Publication No. 58-22
The invention described in Japanese Patent No. 163 has the following configuration.
That is, the difference in height between the field scene and the cultivator is detected by sensing the lifting sensor that detects the difference in height between the aircraft and the float that is in contact with the field scene on the lower surface thereof. The inclination of the machine body in the left-right direction is configured to be detected by a pair of left and right float-shaped rolling sensors disposed on both left and right sides of the machine body being pushed upward in a field scene.

Then, a balance body that is configured to be movable back and forth and horizontally rotatable with respect to the machine body is connected to one lifting hydraulic cylinder that appears in the front-rear direction of the machine body, and a pair of left and right wheels are attached to the balance body. Then, the left and right wheels are configured to move up and down at the same time, while another rolling hydraulic cylinder is inserted in the balance body, and the balance body is rotated by its drive to move the left and right wheels in opposite directions. It is configured so that it can move up and down, and thus corrects the lateral tilt of the aircraft.

[Problems to be solved by the invention]

In this case, for example, when the machine is moving in the horizontal state of its left and right, if the machine passes through a place where the left cultivator is sinking, the left wheel sinks downward so that it touches the cultivator. Put in. Therefore, the rolling sensor on the left side is pushed up by receiving upward pressure from the field scene, and the rolling sensor on the right side moves downward because it is floating from the field scene. Then, the float on the lower surface of the fuselage is pushed upward.

Then, while the right wheel is raised and the left wheel is lowered, rolling control is performed, and at the same time, so-called simultaneous raising / lowering control in which both the left and right wheels are lowered simultaneously is also performed.

In that situation, if the so-called simultaneous ascent / descent speed at which both left and right wheels descend simultaneously is higher than the rolling speed at which the left and right wheels ascend and descend in opposite directions, the aircraft will rise while tilting to the right, and then the right side of the aircraft will Since the aircraft descends and returns to the normal posture in which the left and right sides of the aircraft are approximately horizontal, the right side of the aircraft greatly separates from the field scene while the simultaneous lifting control is operating, and the seedling planting depth by the seedling planting device on that side is increased. However, there is a problem that the so-called floating seedling phenomenon occurs.

It is an object of the present invention to detect a difference between a machine body and a field scene to perform simultaneous raising / lowering control and rolling control, and to solve the inconvenience that occurs at that time.

[Means for solving problems]

Therefore, according to the present invention, a pair of left and right wheels disposed on both left and right sides of a machine body equipped with a seedling planting device is provided with one lifting drive means by sensing a lifting sensor for detecting the height between the machine body and the field scene. In addition to raising and lowering all at once via the rolling sensor, the left and right wheels in the ascending / descending state are moved up and down in opposite directions through the rolling drive means by the detection of the rolling sensor that detects the lateral tilt of the aircraft. The vertical ascending / descending speed of the left and right wheels and the vertically moving speeds of the left and right wheels in the opposite directions are substantially the same.

[Operations and Effects of the Invention] As in the present invention, if the simultaneous raising and lowering speeds of the left and right wheels and the speeds of vertically moving in opposite directions are substantially the same, for example, the movements of the left and right wheels that are about to descend simultaneously can be improved. On the other hand, the rolling control doubles the downward movement speed of one wheel that should be corrected to one side of the aircraft upward, and cancels the upward movement speed of the other wheel that should be corrected to sink the other side of the aircraft. It operates in a coordinated manner and the left and right sides of the aircraft can be quickly corrected to the horizontal state.

Therefore, as in the past, when the left and right wheels are first lowered all at once and then the left and right wheels are operating in reverse, the delay in correction control of the aircraft's lateral inclination is eliminated, and swift seedling control can be expected. The phenomenon does not occur.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, a front part of a transmission case 2 is an engine base 3 having a downward U-shaped cross section, which is a front frame, and a rear part is a transmission case 5 via a frame 4. And a pair of left and right wheels 7, 7 on both left and right sides of the machine body 6 and a central float 8 longitudinally arranged on the lower surface of the machine body 6.
A pair of left and right rocking type seedling planting mechanisms 9 are attached to the transmission case 5, and the left and right sides of the central float 8 are attached to each of the seedling planting mechanisms 9. The plant is constructed so that seedlings can be planted.

At the rear of the transmission case 5, a pair of left and right steering handles 11,1
1 is attached, and a seedling stand 10 is mounted on the upper surfaces of the pair of steering handles 11, 11 so as to be capable of reciprocating left and right.

A bumper 12 is provided at the front end of the engine base 3 so as to project to the left and right sides, while a hydraulic unit 13 is placed in front of the engine base 3 and an engine 14 is mounted adjacent to the hydraulic unit 13. In addition, the left and right wheels 7,7 are provided on the lower surface of the engine base 3.
A lifting hydraulic cylinder 15 which is a lifting driving means for simultaneously lifting and lowering the vehicle and a rolling hydraulic cylinder 16 which is a rolling driving means for controlling the lateral inclination of the machine body 6 are mounted.

Further, a pair of left and right float-like sensors 17a, 17b in a rolling sensor mechanism 22 associated with the rolling hydraulic cylinder 16 are arranged at the front and rear positions of the wheels 7, 7 at the left and right positions of the central float 8. A pivot arm 70, whose front ends of the float-like sensors 17a and 17b will be described in detail later,
The bumper 12 is mounted on the rear surface side of the bumper 12 through 70 so as to be vertically rotatable.

The front end portion of the central float 8 has a link 51 projecting therefrom facing a vertically communicating gap between the front end of the engine base 3 and the bumper 12 so that the link 51 has a vertical longitudinal hole.
The pin 53 provided in the gap is fitted into the space 52 to be vertically movable, and the vertical lengthwise hole 52 regulates the vertical size of the entire central float 8.

Also, the seedling planting depth adjusting rod 5 provided between the steering handles 11 and 11.
The lower end of 4 is pivotally attached to the upper surface of the rear part of the central float 8, and by this, the height of the rear part of the central float 8 with respect to the lower surface of the body 6 is adjusted to increase the depth of seedling planting in a field scene by the seedling planting mechanism 9. Configure to be adjustable.

The both wheels 7, 7 are swing arms 18a, 18b pivotally attached to drive shafts 19 projecting from the left and right side surfaces of the mission case 2 so as to be vertically rotatable at their base ends and extending rearward.
Attached to the tip of each engine 19 on the engine base 3
From the belt 21 to the pulley 20 on one side of the mission case 2
It is rotationally driven by the power from the transmission mechanism in the transmission case 2 that is transmitted.

A double-acting lifting hydraulic cylinder 15 for vertically moving the left and right swing arms 18a, 18b in the same direction to vertically move the left and right wheels 7, 7 at the lower surface position of the engine base 3, The rear end is attached to the rear plate 23 of the engine base 3.

The piston rod 24 of the lifting hydraulic cylinder 15 is arranged so as to project in the forward direction of the rice transplanter 1, and the middle portion of the left and right longitudinal pipe members 26 attached to the piston rod 24 via the attachment piece 25 The front and rear longitudinal guide grooves 28, 28 of the left and right vertical plates 27, 27 of the engine base 3 are fitted so as to be movable back and forth.

A bracket 30 projecting upward from the left end of the inner shaft 29, which is rotatably fitted around the axis of the pipe member 26 in the machine body traveling direction, and an arm 31 at the base end of the left swing arm 18a are connected to a connecting rod 32a. On the other hand, the bracket 30 fitted to the right end of the inner shaft 29 and protruding downward from the boss 34 fixed to the pin 33 and the right swing arm 18b proximal end arm 31 are connected by the connecting rod 32b. . This allows the piston rod 24
When the swing arm 18a, 18b pivots upward via the inner shaft 29, the wheels 7, 7 rise simultaneously, and the piston rod 24 moves backward to swing both swing arms 18a, 18b. The arms 18a and 18b are rotated downward so that both wheels 7 and 7 are simultaneously lowered.

At this time, the guide members 35, 35 projecting from the pipe member 26 are brought close to the left and right vertical plates 27, 27 of the engine base 3 to prevent the pipe member 26 from being displaced in the left-right direction. While it can be moved along the front-rear longitudinal guide grooves 28, 28, the inner shaft 29 is fitted in the longitudinal tube member 26 on the left and right, so that the swing arms 18 on both the left and right sides can be moved.
Even if the a and 18b rotate in mutually opposite directions, the piston rod 24 of the lifting hydraulic cylinder 15 will not be twisted.

The rolling hydraulic cylinder 16 has a piston rod 36 pivotally attached to a bracket in the middle of the inner shaft 29, while the rear end of the double-acting rolling hydraulic cylinder 16 is a bracket protruding rearward from the pipe member 26. A pin is pivotally attached to 37, and a rolling sensor mechanism 22 and an engine base 3 described later are provided.
By operating the upper hydraulic unit 13, the rolling hydraulic cylinder 16 is driven to rotate the inner shaft 29 around its axis, so that both wheels 7 move up and down in opposite directions. As a result, so-called rolling control is performed in which the left and right sides of the machine body are substantially horizontal.

The hydraulic unit 13 constituting the hydraulic circuit 43 for operating the lifting hydraulic cylinder 15 and the rolling hydraulic cylinder 16 includes a hydraulic pump 44, an oil tank 45, a distribution valve 46, and switching of hydraulic pressure to the lifting hydraulic cylinder 15. Parts such as a rotary type switching valve 47 for carrying out the above, a spool type switching valve 48 for switching the hydraulic pressure to the rolling hydraulic cylinder 16 and the like are integrally mounted and gathered in one place. The power transmission from the engine 14 to the hydraulic pump 44 is performed via the belt 49 and the pulley 50.

Reference numeral 55 denotes a lifting sensor that operates a rotary switching valve 47 that switches the hydraulic pressure to the lifting hydraulic cylinder 15, and the lifting sensor 55 is a vertical rotation unit pivotally supported on one side vertical plate 27 of the engine base 3. Movable arm 56 Roller 57 at the tip
While contacting the upper surface of the central float 8, a lever 58 attached to the base end of the arm 56 is connected to the shaft of the rotary switching valve 47.

The rolling sensor mechanism 22 for operating the rolling hydraulic cylinder 16 includes a pair of left and right float-like sensors 17a, 17b arranged so as to slide on a field scene on both left and right sides of the central float 8, and Hydraulic unit 13
A balance-type link mechanism 62 mounted on the top and a pivotal arm that supports the base end portions that are the front ends of the pair of left and right float-like sensors 17a and 17b and that is connected to the balance-type link mechanism 62.
It consists of 70 and 70.

The balance type link mechanism 62 has a structure in which the bracket 1 projecting on the hydraulic unit 13 is mounted on the bracket 1 from substantially the right and left central portions of the body.
A boss that is rotatably fitted to a horizontal shaft 63 that extends in the front-rear direction.
A cylindrical balance rod 65 extending in both left and right directions of the machine body is fixed to the lower end of 64 so that the balance rod 65 can be rotated up and down.
The arms 67, 67 attached to the left and right ends of the shaft 66 rotatably fitted therein, are provided with a link 69, which has a turnbuckle 68, respectively.
One end of 69 is pivotally attached, and the other ends of both links 69, 69 are fitted in the mounting holes 71 for sensitivity adjustment of the left and right pivotal arms 70, 70 so that their positions can be changed.

As a result, if the rear end of one of the float-shaped sensors descends and the rear end of the other float-shaped sensor rises, the balance rod 65 pivots up and down around the horizontal axis 63 accordingly.

Further, by engaging the horizontal tip end of the spool shaft 74 of the switching valve 48 with the engagement hole 73 of the bracket 72 attached to the balance rod 65, the balance rod 65 can be vertically rotated in the lateral direction of the machine body. Then, the switching valve 48 is caused to switch the hydraulic pressure to the rolling hydraulic cylinder 16.

Each of the bushes 75 at the base ends of the pivot arms 70, 70 is rotatably fitted to a horizontal pivot portion 76a of a lateral U-shaped pivot member 76 attached to the lower surface of the bumper 12.

At the base end of each pivot arm 70, a restriction plate 78 having an upwardly open restriction groove 77 cut out is rotatably mounted.
The restriction groove 77 is made to face the protrusion 76b of the pivot member 76 to restrict the swing angle of each sensor 17a, 17b in both the up and down directions. The restricting plate 78 is attached to the arcuate long groove of the pivot arm 70 through a bolt 79 inserted into the arcuate long groove so that its position can be adjusted, and the center position of the projection 76b with respect to the restricting groove 77 is adjusted to adjust the float sensor 17a. It is possible to change the upward movable amount and the downward movable amount of 17b.
The rolling controllable range can be changed.

The horizontal plates of the reinforcing brackets 80, 80 at the base end portions of the left and right float type sensors 17a, 17b are attached to the left and right pivot arms 7.
It is placed on the upper surface of the horizontal plate of 0, 70, and between the two, a pair of front and rear compression springs that can tilt the float sensor so that the external force is released if the external force to the float sensor exceeds a certain level. Overload prevention means consisting of 81 vertical bolts 82
84 is provided.

A link 85 with an elongated groove is rotatably attached to the rear ends of both float-shaped sensors 17a and 17b, and both links 85 and 85 are attached to the front ends of the swing arms 17a and 17b, and the shaft of a bracket 86 is projected forward. It is fitted on 87, and as a result, it is possible to prevent interference between the center of rotation of the swing arm and the rear end of the float sensor when the wheels are raised.

Reference numeral 38 is a balance link mechanism on the hydraulic unit 13.
Reference numeral 41 is a bonnet cover that covers the upper side of the transmission case 5 behind 62. Reference numeral 41 indicates the rotation of the inner shaft 29 by operating the hand handle 42 near the control handle 11 in preference to the operation of the rolling hydraulic cylinder 16. By blocking, the rolling lock mechanism stops the upside-down operation of the both wheels 7, 7. On the other hand, the handle near the control handle 11
An operating rod 60 connected to 59 is connected to the rotary shaft of the rotary type switching valve 47 via an expandable joint 61, and by operating a hand handle 59, the rotary lever is given priority over the operation of the lifting sensor 55. By switching the switching valve 47, the both wheels 7, 7 can be operated simultaneously in the vertical direction.

Further, in the present invention, the simultaneous lifting speed of both the left and right wheels by the lifting hydraulic cylinder 15 which is the lifting driving means, and the vertical movement speed of the rolling hydraulic cylinder 16 which is the rolling driving means for vertically moving in the opposite directions. And are configured to be substantially the same.

In one embodiment thereof, arms 31 and 31 for rotating the left and right swing arms 18a and 18b around the drive shaft 19 in FIG.
The rotation angular velocities of are made substantially the same. Therefore, when the diameters of both the hydraulic cylinders 15 and 16 are equal and the projecting and retracting speeds of the piston rods are the same, the lengths of the brackets 30 and 30 and the length of the link 36b that rotates the inner shaft 29 by the hydraulic cylinder 16 are set to be equal to each other. By appropriately setting the ratio, the rolling hydraulic cylinder 15 rotates the arms 31 and 31 in opposite directions via the connecting rods 32a and 32b, and the pipe member 26 to which the link mechanism is attached moves up and down. The angular velocity at which both arms 31, 31 are simultaneously rotated in the same direction by moving the cylinder 16 back and forth is set to be the same. Alternatively, when the retracting speeds of the both hydraulic cylinders 15 and 16 are set to a constant ratio, the arm 31 and the bracket are set so as to be equal to the rotational angular speed of the arm 31 due to the longitudinal movement speed of the pipe member 26. The ratio of the link mechanism consisting of 30,30 etc. should be set.

These settings will be described in more detail. FIG. 11 schematically shows the embodiment of FIG. 4, in which the forward / backward axis of the piston rod of the hydraulic cylinder 15 is used as a reference line, and the inner cylinder 29 is moved by the hydraulic cylinder 15. The axis of is Vo centimeters per second
Suppose you move to the left in Fig. 11 and come to point 29 '. As a result, the arm 31 attached to the base end of the swing arm 18a (18b)
Rotates about the drive shaft 19 by θo per second.
In the meantime, in order to rotate the left and right swing arms 18a (18b) in opposite directions at the same angular velocity, it is necessary to rotate the bracket 30 clockwise by θ2 in FIG. The link 36b that rotates integrally with the bracket 30 is a connection point (pivot point) 36a with the piston rod 36 of the hydraulic cylinder 16.
It is connected with. Therefore, it suffices to rotate the link 36b clockwise by θ2 per second in FIG.

It is assumed that the angle formed by the axis of the hydraulic cylinder 16 and the reference line of the hydraulic cylinder 15 is θ1, and that the change in θ1 during the movement from the connecting point 36a to 36a ′ is minute, the piston rod 36 is When moving backward at V1 per second, the horizontal movement distance per second from point 36a to point 36a 'Vx ≈ V1cos (θ
It becomes 1).

If the length of the link 36b (= length from point 29 to point 36a) is L1 and the length of the bracket 30 (= length from point 29 to point 30a) is L2, The moving distance in the direction parallel to the reference line is Vx ′ = Vx × (L2 / L1).
Therefore, if Vo = Vx ′, the relational expression of Vo≈V1 × (L2 / L1) × cos (θ1) is established. By transforming this, the relational expression of (Vo / V1) ≈ (L2 / L1) × cos (θ1) is established.

When the advancing / retreating speeds of the piston rods of both hydraulic cylinders 15 and 16 are equal, Vo / V = 1.
Ratio of b to bracket 30 length (L1 / L2) ≈ cos (θ1)
It should be done.

According to this configuration, when the piston rod 24 of the lifting hydraulic cylinder 15 is caused to project forward during rice planting work, both swings interlocking via the pipe member 26, the inner shaft 29, the connecting rods 32a and 32b, and the arms 31 and 31. Since the arms 18a, 18b rotate upward, the wheels 7, which are attached to the ends of the swing arms,
7 simultaneously rises with respect to Aircraft 6 and descends.

The central float 8 on the lower surface of the body 6 descended in this way
If the wheels 7 and 7 are driven in a state where the plant is grounded in the field, the machine goes straight, and by driving the seedling planting mechanism 9, the seedling planting nails are used to plant seedlings from the seedling mat on the seedling mounting table 10. It is possible to plant seedlings along multiple lines in the field while splitting one by one.

At this time, when the machine body rolls and tilts so that the right side of the machine body 6 faces downward in FIG. 8, for example, the sensor 17b on the right side is pushed up by the field scene, and the balance type link mechanism 6
The spool cylinder 74 of the switching valve 48 is pulled up via the link 69 of 2 and the cylindrical balance rod 65 to switch the hydraulic cylinder 16 for rolling.
By sending hydraulic pressure to, the piston rod 36 of the rolling hydraulic cylinder 16 is projected, the inner shaft 29 is appropriately rotated, and the right wheel 7 is pushed down while the left wheel 7 is pushed down (see FIG. 4). A so-called rolling control is performed in which the right side of the vehicle is lifted to restore the left and right of the machine body 6 to a substantially horizontal shape.

At the same time, the central float 8 on the lower surface of the machine body 6 is also pushed upward from the field scene, and the switching valve 47 is switched via the lifting sensor 55 contacting the upper surface of the central float 8 to move the piston rod of the lifting hydraulic cylinder 15. 24 is pulled in, the left and right wheels 7, 7 are lowered all at once, and the body 6 is raised accordingly.

In both of these controls, the speed at which the left and right wheels 7, 7 are lowered simultaneously and the speed at which the wheels are moved up and down in opposite directions are substantially the same. The wheel on one side should move quickly downward, and the wheel on the other side should not move up and down, so that the tilt of the body can be corrected quickly.

FIG. 10 shows a second embodiment of the present invention, in which a balance rod 90 is horizontally pivotably attached to a piston rod of a hydraulic cylinder 15 for lifting and lowering to and from the machine body 6 so that the balance rod 90 has right and left ends. And the left and right swing arms 18a, 18b are connected to each other. The middle part of one of the connecting rods 91, 91 is a hydraulic cylinder for rolling.
A pair of left and right float type rolling sensors 17a and 17b connected to each other are attached to a balance type link mechanism 92 which can be swung to the left and right of the machine body and which can be swung up and down, and a switching valve 48 of the balance type link mechanism 92. ′ Through hydraulic cylinder for rolling
On the other hand, 16 is driven, while a raising / lowering sensor 55 and a switching valve 47 'which are related to detect the vertical movement of the central float 8 on the lower surface of the machine body 6 are connected, and the raising / lowering hydraulic cylinder 15 is driven from there.

At this time, considering the ratio of the arm length of the so-called balance rod 90 from the central portion of the balance rod 90 to which the piston rod of the lifting hydraulic cylinder 15 is attached to the place where the piston rod of the hydraulic cylinder 16 for rolling is attached. By appropriately setting the retracting speed ratio of the piston rods of the hydraulic cylinders 15 and 16, the simultaneous up-and-down speed of the left and right wheels and the up-and-down speed of the left and right wheels in opposite directions can be made substantially the same. .

FIG. 12 is a schematic view of the embodiment of FIG. 10, in which the point 15a is the distance Vo per second at the advancing / retreating reference line of the connecting point 15a between the piston rod of the hydraulic cylinder 15 and the balance rod 90. Suppose you move in centimeters and come to point 15a '. As a result, the balance rod 90 moves in parallel, and the connection point 90a with the connecting rod 91 moves to the point 90a '. In order to make the simultaneous vertical ascending / descending speed of both the left and right wheels and the vertically moving speed of the left and right wheels opposite to each other approximately the same, the piston rod of the hydraulic cylinder 16 is retracted within the above time, and the balance rod 90 is moved by θ1. The point 90a 'may be rotated to return it to the point 90a. Now, the arm length of the balance rod 90 (= the length from the point 15a to the connecting point 90a) is set to L, and the connecting rod 0 of the hydraulic cylinder 16 is set to 0.
The angle between the reference line and the reference line is θ2. Hydraulic cylinder
Assuming that the variation of the angle θ2 when the point 90a ′ returns to the point 90a is very small when the 16 piston rods retreat at the distance V1 per second, the component in the reference line direction Vx≈V1 × co
s (θ2).

On the other hand, the relational expression when the balance rod 90 is rotated by θ1 is
Vo = L × sin (θ1). If Vo = Vx, the relational expression L × sin (θ1) ≈V1 × cos (θ2) is obtained.

Further, in each of the above-described embodiments, the lifting cylinder driving means for vertically moving both the left and right wheels and the rolling driving means for vertically moving the left and right wheels in opposite directions to each other may be replaced with the hydraulic cylinders instead of electric cylinders. You can also

[Brief description of drawings]

The drawing shows an embodiment of the present invention, and FIG. 1 is a II-II of FIG.
2 is a side view of the rice transplanter, FIG. 3 is a sectional view taken along line III-III of FIG. 2, and FIG. 4 is of FIG.
IV-IV line main part enlarged side view, FIG. 5 is a sectional view taken along line VV of FIG. 2, FIG. 6 is a VI-VI line main part enlarged side view of FIG. 2, and FIG. FIG. 7 is an enlarged sectional view taken along the line VII-VII of FIG.
Figure VIII-VIII line side view of the main part, Figure 9 is a hydraulic circuit diagram,
FIG. 10 is a schematic view showing the second embodiment, FIG. 11 is an operation explanatory view for the FIG. 4 embodiment, and FIG. 12 is an operation explanatory view for the FIG. 10 embodiment. 1 ... Rice transplanter, 2 ... Mission case, 3 ... Engine stand, 4 ... Frame, 5 ... Transmission case, 6 ... Aircraft, 7 ... Wheels, 8 ... Central float, 9 ... Seedling planting Mechanism, 10 ... Seedling table, 11 ... Steering handle, 18a, 18b ...
Swing arm, 14 …… Engine, 15 …… Up and down hydraulic cylinder, 16 …… Rolling hydraulic cylinder, 24,36 ……
Piston rod, 17a, 17b ... Float sensor, 22
…… Rolling sensor mechanism, 62 …… balance type link mechanism, 13 …… hydraulic unit, 44 …… hydraulic pump, 45 …… oil tank, 47,48 …… switch valve, 26 …… tubular member, 29 …… Inner shaft, 28,28 …… Guide groove, 30,30 …… Bracket, 32a, 32
b …… Continuous rod, 34 …… Boss, 55 …… Sensor for lifting, 65…
… Cylindrical balance rod, 67,67 …… arm, 69,69 …… link, 74
…… Spool shaft, 70,70 …… Pivot arm, 76 …… Pivot member, 80 …… Reinforcing bracket, 81 …… Compression spring, 82 …… Vertical bolt, 84 …… Overload prevention means, 92 …… Balance-type link mechanism, 90 …… balance rod, 91 …… continuous rod.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadashi Kondo 1-32, Chayacho, Kita-ku, Osaka City, Osaka Prefecture Yanmar Agricultural Machinery Co., Ltd. (56) References Japanese Patent Publication Sho 58-22163 (JP, B2)

Claims (1)

[Claims] 1. A pair of left and right wheels disposed on both left and right sides of a machine body equipped with a seedling planting device, through one lifting drive means by detection of a lifting sensor for detecting the height between the machine body and the field scene. In parallel with the vertical movement, the rolling sensor detects the lateral tilt of the machine, and the left and right wheels in the ascending / descending state are moved up and down in opposite directions via the rolling drive means to tilt the machine in the lateral direction. An attitude control device for a rice transplanter, which is configured to be corrected so that the simultaneous up-and-down speed of the left and right wheels and the up-and-down movement speed of the left and right wheels in opposite directions are substantially the same.