JP2017112838A - Agricultural work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an agricultural work machine suppressing hunting of a ground levelling device by stopping ground levelling height control of the ground levelling device during non-work time.SOLUTION: An agricultural work machine includes: rice field height detection means detecting rice field height as height from a prescribed portion of a ground work part to the rice field surface; work state detection means detecting a work state of the ground work part; and control means connecting these detection means to an input side while connecting vertical position adjustment means to an output side. When the work state of the ground work part is detected by the work state detection means, a ground levelling device is controlled for ground levelling height through the vertical position adjustment means based on a detection value detected by the rice field height detection means. When the work state of the ground work part is not detected by the work state detection means, the ground levelling height control of the ground levelling device is stopped.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an agricultural machine, and more particularly, a ground leveling device is disposed between the traveling unit and the ground level working unit, and the leveling height of the leveling device can be controlled. The present invention relates to farming machines such as riding rice transplanters and direct sowing machines that are stopped.

  Conventionally, there exists what was disclosed by patent document 1 as one form of an agricultural machine. That is, in Patent Document 1, a planting part that allows planting seedlings to be planted in a farm field is attached to the rear of the traveling part that is capable of self-propelling, and the field leveling is performed just before the planting part. A riding rice transplanter has been disclosed in which a device is attached so that the vertical position can be adjusted so that seedlings can be planted in a farmed field.

  In this riding rice transplanter, the planting part is controlled (planting) so that the planting depth of the seedling by the planting part is maintained at the set depth based on the planting set height (set depth). Control) and the leveling height of the leveling device is controlled so that the leveling device is maintained at the leveling set height from the surface.

JP2008-263884

  However, in the above-mentioned riding rice transplanter, the leveling height of the leveling device is based on the height of the lower end of the planting part, that is, the height of the bottom surface of the float determined by the planting setting height (setting depth). Since the leveling height of the leveling device is changed in conjunction with the height of the bottom surface of the float, the leveling height of the leveling device is controlled even during non-planting operations such as when the aircraft is turning. As a result, the leveling device hunts and the durability of the actuator or relay that changes the height of the leveling device is reduced.

  Then, an object of this invention is to provide the agricultural machine which can suppress the hunting of the leveling apparatus by stopping the leveling height control of the leveling apparatus at the time of non-working.

The invention described in claim 1
A ground working unit is attached to the rear of the traveling unit via an elevating mechanism unit so that the ground working unit can be raised and lowered, and a ground leveling device for leveling a farm scene is disposed between the traveling unit and the ground working unit. An agricultural machine that can adjust the leveling height by adjusting the vertical position by means of vertical position adjustment means,
A farm scene height detecting means for detecting a farm scene height which is a height from a predetermined position of the ground working unit to the farm scene;
Working state detecting means for detecting the working state of the ground working unit;
While connecting these detection means to the input side, the control means connected the vertical position adjustment means to the output side,
With
When the work state of the ground working unit is detected by the work state detection means, the leveling device controls the leveling height via the vertical position adjustment means based on the detection value detected by the field scene height detection means. And configured to be
When the work state of the ground working unit is not detected by the work state detecting means, the leveling height control of the leveling device is stopped.

  In the first aspect of the invention, when the work state of the ground working unit is not detected by the work state detection means (when not working), the leveling height control of the leveling device is stopped, Hunting of the leveling device can be suppressed. Therefore, the use frequency of the actuators and relays constituting a part of the vertical position adjusting means for changing the height of the leveling device is reduced, and the durability can be ensured satisfactorily. In addition, since there is no need to perform leveling height control of the leveling device when not working, there is no problem even if the leveling height control is stopped.

Invention of Claim 2 is invention of Claim 1, Comprising:
The work state detection means is a float angle detection means for detecting a float angle, and the float angle detection means constitutes a part of the control mechanism so that the work depth by the ground work section is maintained at the set depth. It is characterized by.

  According to the second aspect of the present invention, the float angle detection means that constitutes a part of the control mechanism is used as the work state detection means so as to detect the work state. As a result, the manufacturing cost can be reduced. At this time, if the float angle detecting means detects a depression angle of the float that is greater than or equal to the predetermined value, the control means that has acquired the detection result determines that the ground working unit is in a non-working state, and controls the leveling height. To stop.

Invention of Claim 3 is invention of Claim 1, Comprising:
The work state detection means is a field scene height detection means for detecting the field scene height by touching the field scene, and the field scene height detection means constitutes a part of the control mechanism. Features.

  In the invention according to claim 3, since the farm scene height detection means that constitutes a part of the control mechanism is used as the work state detection means, the work state is detected. The manufacturing cost can be reduced. At this time, if the farm scene height detection means is separated from the farm scene and is in a non-grounded state, that is, if the farm scene height cannot be detected, the farm scene height is detected within a predetermined time. The control means that cannot obtain the result determines that the ground working unit is in the non-working state, and stops the leveling height control.

  According to the present invention, since the leveling height control of the leveling device is stopped when not working, it is possible to provide an agricultural machine capable of suppressing hunting of the leveling device.

The left view of the rice transplanter as this embodiment. The left view of a planting part. The front view of a planting part. Control block diagram. Explanatory drawing of the left side of a planting part. Control structure explanatory drawing of a center float. Plane explanatory drawing of a surface height detection means. Control procedure explanatory drawing. Explanatory drawing of the work state detection means as other embodiment. Plane explanatory drawing of the float of a planting part. FIG. 11 is a view taken along the line I-I in FIG. 10. II-II arrow directional view of FIG. Explanatory drawing of the left side of a planting depth setting means. Front explanatory drawing of a planting depth setting means. Explanatory drawing of the left side of the planting depth setting means as a modification. Front explanatory drawing of the planting depth setting means as a modification. The perspective explanatory drawing of an up-and-down position adjustment means. Plane explanatory drawing of an up-and-down position adjustment means. The left view of an up-and-down position adjustment means. The left side operation | movement explanatory drawing of an up-down position adjustment means. Expansive plane explanatory drawing of an up-and-down position adjustment means. The perspective explanatory view of the up-and-down position adjusting means as another embodiment. Control timing chart. The left view of the traveling part as other embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. That is, A shown in FIG. 1 is a riding rice transplanter as a farm working machine according to the present embodiment. The riding rice transplanter A uses the seedling N as a field scene of the field G behind the traveling unit 1 capable of self-propelling. A planting unit 2 as a ground working unit that can be planted on the paddy field Fs (see FIG. 5) is attached via a lifting mechanism unit 3 so as to be lifted and lowered. A leveling device 4 for leveling the field surface Fs is disposed between the traveling unit 1 and the planting unit 2, and the leveling device 4 can adjust the leveling height by adjusting the vertical position by the vertical position adjusting means 52. It is said. The field G here has a case where the surface water is stretched on the surface Fs at a desired depth of several centimeters and a case where the surface water is not stretched. In this embodiment, the surface water is not stretched. The riding rice transplanter A of the present embodiment can also be applied to the case where

[Overview of riding rice transplanter]
As shown in FIG. 1, the traveling unit 1 includes a lower structure 10 and an upper structure 11 disposed on the lower structure 10. The lower structure 10 has a front axle case (not shown) to which a pair of left and right front wheels 12 and 12 are attached and a rear axle case 15 to which a pair of left and right rear wheels 14 and 14 are attached at a constant interval in the front-rear direction. The case 15 is opened and connected to each other via a connecting support body 16 that extends in the front-rear direction. On the front axle case, a mission case 18 is linked and connected to extend forward from the mission case 18 to form a front support body 17. The transmission case 18 and the rear axle case 15 are interlocked and connected via a transmission shaft 19. 12 a is an axle of the front wheel 12, and 14 a is an axle of the rear wheel 14.

  The upper structural body 11 has the engine 20 mounted on the front support body 17 and interlocks the engine 20 and the transmission case 18. The engine 20 and the steering shaft 21 disposed immediately behind the engine 20 are covered with a bonnet 22, and a steering wheel 23 is attached to the upper end portion of the steering shaft 21. An operation panel 22 a is stretched on the upper end of the bonnet 22. A flat step portion 24 is stretched around and around the bonnet 22, and a seat support base 25 is integrally connected to the rear from the step portion 24. A seat 26 is provided on the seat support 25. A transmission mechanism case 27 is provided at the rear portion of the transmission shaft 19 and attached to the front wall of the rear axle case 15. The transmission mechanism case 27 transmits power transmitted from the engine 20 via the transmission shaft 19 to the leveling device 4 described later.

  As shown in FIG. 9, the operation panel portion 22 a is provided with a main transmission lever 70 on the left side through a lever guide groove 71, and on the right side, an elevation operation lever 72 for raising and lowering the planting portion 2. It is arranged. The main transmission lever is linked to the transmission case 18 so that the transmission case can be operated in the main transmission in each of the following states: movement transmission, forward transmission, neutral transmission, reverse transmission, and seedling transmission. The lever guide groove 71 is formed to extend in the front-rear direction. The main transmission lever 70 is slidably inserted into the lever guide groove 71 and the main transmission lever 70 is slid to the main transmission operation position described above. It can be operated dynamically. The elevating operation lever 72 is connected to the elevating cylinder 43 via a control means 53 and a control valve 44 described later, and the elevating cylinder 43 can elevate the planting unit 2. When the lifting / lowering operation lever 72 is tilted forward, the lifting / lowering cylinder 43 extends and the planting part 2 is lowered. On the other hand, when tilting backward, the lifting / lowering cylinder 43 is shortened and the planting part 2 is moved. I try to rise. Further, the operation panel unit 22a has a planting depth setting operation unit 190 which is a volume type switch for setting (user setting) the planting depth according to the operator's preference, and the leveling height according to the operator's preference. Leveling height setting operation means 192 which is a volume type switch for setting (user setting) is provided.

  Then, power is transmitted from the engine 20 to the transmission case 18 → the front axle case and the transmission shaft 19 → the rear axle case 15 so that the front and rear wheels 12, 12, 14, and 14 can be driven. The upper structure 11 is provided with an operation tool (not shown) for operating the operation unit 1.

  As shown in FIGS. 1 and 2, the planting unit 2 is provided with a planting mission case 29 via a planting frame 31. The planting frame 31 includes a pair of left and right vertically extending pieces 31a and 31a extending in the up and down direction, and a middle part left and right extending piece 31b horizontally extending between the middle parts of both the vertically extending pieces 31a and 31a. The lower left and right extended pieces 31d are horizontally extended between the lower portions of the upper and lower extended pieces 31a and 31a. The planting frame 31 is formed in a rectangular frame shape when viewed from the front, and is erected toward the front upper side. The lower left and right extended pieces 31d are formed in a square pipe shape in cross section, and a plurality of (four in this embodiment) planting transmission cases 30 are extended from the lower left and right extended pieces 31d to the rear. These planting transmission cases 30 are arranged at appropriate intervals in the left-right direction. A planting mission case 29 is placed on the center of the lower left and right extending piece 31d. In the rear part of the planting mission case 29, a middle part of the transmission shaft case 38 extending to the left and right sides is interlocked and connected, and each planting transmission case 30 is interlocked to the planting mission case 29 via the transmission shaft case 38. It is connected. Above the planting mission case 29, a seedling stage 32 is attached via a planting frame 31 so as to be capable of reciprocating left and right.

  A center portion of the rotary case 33 is rotatably attached to the rear portion of each planting transmission case 30 via a rotation shaft 39, and planting claws 34 and 34 are attached to both ends of the rotary case 33. Below the planting transmission case 30 and the like, a center float 35 that is a sensor float and two side floats 36 are arranged on each of the left and right sides thereof, and the planting transmission case 30 and the like are provided by these floats 35 and 36. Is supported on the surface Fs. 37 is a planting transmission shaft. The planting transmission shaft 37 includes a power take-off shaft (not shown) provided at the rear end of the traveling unit 1 and an input shaft projecting forward from the planting mission case 29. (Not shown).

  Then, power is taken into the planting mission case 29 from the traveling unit 1 through the planting transmission shaft 37, and the power is transmitted from the planting mission case 29 to the planting transmission case 30 through the transmission shaft case 38. By rotating the rotary case 33 attached to the attached transmission case 30, the seedling N (seedling stock) is transferred from the seedling mat M placed on the seedling placing stand 32 by the planting claws 34, 34 attached to both ends of the rotary case 33. ) Is cut to plant seedlings N (seedlings) on the field surface Fs. K is a planting locus (see FIG. 5). Reference numeral 45 denotes a seedling removal amount adjusting lever.

  As shown in FIGS. 1 and 2, the elevating mechanism unit 3 is disposed in the front-rear direction between the vertical frame 28 erected on the rear axle case 15 of the traveling unit 1 and the planting frame 31 of the planting unit 2. A top link 40 that extends and a pair of left and right lower links 41, 41 extending in the front-rear direction are provided, and the upper ends of the connecting pieces 42, 42 formed by projecting upward from the front portions of the lower links 41, 41, and traveling A lifting cylinder 43 is interposed between the connecting support body 16 of the part 1. And the planting part 2 is raised / lowered via the lower links 41 and 41 and the top link 40 by operating the raising / lowering cylinder 43 to extend and contract.

  The leveling device 4 is a device for leveling the field surface Fs (particularly, rough headland), and is attached to the planting frame 31 of the planting unit 2 as shown in FIGS. That is, the leveling device 4 is based on the leveling means 50 that contacts the surface Fs and performs the leveling function, the vertical position adjustment means 52 that adjusts the leveling means 50 in the vertical direction, and the detection result of the actual height of the field surface Fs described later. And a control means 53 for controlling the leveling height of the leveling means 50 by adjusting the leveling means 50 by the vertical position adjusting means 52. The control means 53 is disposed at an appropriate location of the traveling unit 1. A leveling transmission shaft 54 is interposed between the leveling means 50 and the transmission mechanism case 27 of the traveling unit 1. The power from the engine 20 is transmitted to the transmission shaft 19 → the transmission mechanism case 27 → the leveling transmission shaft 54 → the leveling means 50, and the leveling means 50 leveles the surface Fs.

[Description of Characteristic Structure of this Embodiment]
Next, a characteristic structure of the present embodiment in the rice transplanter A configured as described above will be described. As shown in FIGS. 4 to 7, the planting unit 2 according to the present embodiment detects a rice field height H4 as a field height, which is a height from a predetermined location of the planting unit 2 to the rice field Fs. A field height detection means 160 as a field scene height detection means, a float angle detection means 157 as a first work state detection means for detecting the work state of the planting unit 2, and these detection means 160 and 157 The control unit 53 is connected to the input side and the vertical position adjusting unit 52 is connected to the output side. The predetermined part of the planting part 2 here is an axial center position of the float support shaft 121 described later in the present embodiment, and the height from the axial center position of the float support shaft 121 to the surface Fs is a surface height H4. It is said. Moreover, the height from the axial center position of the float support shaft 121 to the lower surface of the center part of the center float 35 located immediately below is set as the planting depth setting height H2.

  Then, when the planting operation state of the planting unit 2 is detected by the float angle detection unit 157 and the detection result is acquired by the control unit 53, based on the detection value detected by the surface height detection unit 160. Thus, the control means 53 controls the vertical position adjusting means 52 appropriately to control the leveling height H1 of the leveling device 4 (the height from the field surface Fs to the lower end of the leveling rotor 61 described later) (hereinafter referred to as “leveling”). Also referred to as “height control”).

  If the planting operation state of the planting unit 2 is not detected by the float angle detection unit 157, the control unit 53 recognizes that the planting unit 2 is in the non-planting operation state, and adjusts the vertical position adjustment unit. By controlling the stop 52, the leveling height control is stopped or stopped.

  That is, when the float angle detection means 157 detects a depression angle of the center float 35 that is greater than or equal to the predetermined value, the control means 53 that has acquired the detection result determines that the planting unit 2 is in a non-planting state. Stop or stop leveling height control.

  The depression angle of the center float 35 above a predetermined value is an angle at which the center float 35 does not contact the surface Fs, and the center float 35 in this case is in a non-grounding mode. Moreover, in this embodiment, the state (grounding mode) in which a part of the planting part 2 is grounded to the surface Fs is used as a determination criterion by the control means 53 in a state where the planting part 2 is planting. In other words, it is determined that the planting unit 2 is not planting (non-planting operation state, non-grounding mode).

  The float angle detecting means 157 is a means for detecting the float angle, as will be described later, and the planting depth H3 of the seedling N by the planting unit 2 (planting claw 34) is maintained at the set depth H2. Part of the control mechanism for controlling the planting depth.

  The control means 53 is a microcomputer device including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and the like. As shown in FIG. 4, on the input side of the control means 53, a planting depth setting operation means 190, a leveling height setting operation means 192, an adjustment operation detecting means (sector gear detector) 110, and a set planting depth are provided. The detection means 135, the float angle detection means 157, the surface height detection means 160, etc. are connected. Further, an electric motor 82, a control valve 44, a planting depth setting motor 191 and the like are connected to the output side of the control means 53.

  The table surface height detection means 160 is pulled by the traveling unit 1 and is grounded to the table surface Fs along with the movement of the planting unit 2 arranged at the planting work position, and along the table surface Fs (the table surface). It is made to slide (to trace the surface of Fs). That is, the rice field height detection means 160 detects the actual height of the rice field Fs (the height of the rice field on which the seedling N is planted). Then, the leveling height H1 of the leveling device 4 is appropriately adjusted by controlling the operation of the vertical position adjusting means 52 based on the detected value of the actual height of the field surface Fs.

  Further, when the center float 35 sinks with respect to the field surface Fs, based on the detection result detected by the field surface height detection means 160, the amount of subsidence of the center float 35 (the amount of sinking into the mud-shaped field surface Fs) H5 is obtained. It can be calculated.

  That is, when the detection body 167 is rotated up and down around the axis of the support rod 166 corresponding to the undulation of the surface Fs, the vertical displacement amount is detected by the sensor body 168, and the detection result is It is transmitted to the control means 53. In the control means 53, the detection value of the field height H4 detected by the field height detection means 160 can be acquired, and the settlement amount H5 of the center float 35 can be calculated and converted.

  In the present embodiment configured as described above, the control unit 53 acquires the detection value of the surface height H4 detected by the surface height detection unit 160, and operates the vertical position adjustment unit 52 based on this detection value. Since the leveling height H1 of the leveling device 4 is controlled and adjusted, the leveling device 4 can be arranged at an appropriate leveling height H1, and the leveling accuracy can be ensured satisfactorily. For example, when the control unit 53 determines that the surface height H4 is high from the detection value of the surface height detection unit 160, the leveling device 4 is appropriately lowered and arranged, while the surface height detection unit 160 detects If it is determined from the value that the field height H4 is low, the leveling device 4 is appropriately raised and arranged.

  At this time, when the planting operation state of the planting unit 2 is not detected by the float angle detecting unit 157 (during non-planting operation), the control unit 53 is configured to stop or stop the leveling height control. ing. Therefore, the leveling height H1 of the leveling device 4 is maintained at the current level, and the leveling device 4 can be prevented from hunting. Therefore, the usage frequency of the electric motor 82 and the relay is reduced as an actuator that constitutes a part of the vertical position adjusting means 52 that changes the height of the leveling device 4, and good durability can be ensured. In addition, since there is no need to perform leveling height control of the leveling device 4 during non-planting work, there is no problem even if this leveling height control is stopped or stopped.

  As the first work state detection means, the planting work state is detected by using the float angle detection means 157 that constitutes a part of the control mechanism for controlling the planting depth. Manufacturing sensors can be reduced by eliminating the need for sensors dedicated to detection.

  The present embodiment is also characterized by the following configuration. That is, as described above, on the input side of the control unit 53, the planting depth setting operation unit 190 for setting the planting depth according to the operator's preference (user setting), and the leveling height according to the operator's preference The leveling height setting operation means 192 for setting the height (user setting), the float angle detecting means 157 as the first work state detecting means, the surface height detecting means 160 and the like are connected. And the control means 53 is made to control the leveling apparatus 4 with the following control procedure (step S1-S8), as shown in FIG.

  (1) The float angle is detected by the float angle detecting means 157 (step S1). The surface height H4 is detected by the surface height detection means 160 (step S2). The leveling height setting operation means 192 is operated by the operator according to preference, and the leveling height H1 is set (user setting) (step S3). The planting depth setting operation means 190 is operated according to the preference by the operator, and the planting depth is set (user setting) (step S4). The leveling height target value is calculated by adding the detected value and the set value (step S5).

  (2) Based on the detection value of the float angle detection means 157, the control means 53 recognizes whether or not the planting part 2 is in the planting work state (the grounding mode in which the center float 35 is grounded to the field surface Fs) ( Step S6). In addition, as a supplement, the control unit 53 determines that the planting unit 2 is in the planting operation state (the detection body forming piece 172 of the table surface height detection unit 160 is placed on the surface Fs based on the detection value of the table surface height detection unit 160. It is recognized whether it is a grounded ground mode).

  (3) When the control means 53 recognizes the planting work state of the planting unit 2 (Yes in step S6), the leveling height H1 matches the leveling height target value calculated as described above. The control means 53 controls the vertical position adjusting operation of the vertical position adjusting means 52 to adjust the leveling height H1, that is, to correct the leveling height H1 (step S7).

  (4) When the control means 53 recognizes the non-planting work state (non-grounding mode) (No in step S6), the leveling height control of the leveling device 4 is stopped or stopped, and the leveling height H1 is the current level. It is maintained as it is (step S8).

  In this embodiment configured as described above, it is possible to calculate the leveling height target value with high accuracy in consideration of the operator's preference, and to improve the leveling height control accuracy of the leveling device 4 to the operator's preference. Can do.

  In addition, even during non-planting work, when the planting clutch (not shown) provided in the planting part 2 is disconnected, the floats 35 and 36 are grounded to the field surface Fs, and the field surface Fs is You can run as much as you can. At this time, although the leveling height control of the leveling device 4 is stopped or stopped, the control unit 53 is operated by operating the lifting operation switch 73 provided on the operation panel unit 22a and connected to the input side of the control unit 53. Accordingly, the leveling device 4 can be moved up and down by the vertical position adjusting means 52.

  Moreover, in this embodiment, although the surface height detection means 160 is provided in the planting part 2, the surface height detection means 160 is provided in the frame 68 of the leveling device 4, and the detection result of the surface height detection means 160 is obtained. The leveling height of the leveling device 4 can be controlled by the control means 53 based on the above.

[Description of Working State Detection Means as Other Embodiments]
Next, second to eighth work state detection means as other embodiments will be described. These second to eighth work state detection means can be appropriately employed instead of the float angle detection means 157 which is the first work state detection means.

  The second work state detection means is a field height detection means 160 that constitutes a part of the control mechanism for controlling the leveling height. The surface height detection means 160 cannot detect the surface height H4 if it is separated from the surface Fs and is in a non-grounded state. If it does so, the control means 53 cannot acquire the detection result of the surface height H4 within the predetermined time. In this case, the control means 53 determines that the planting unit 2 is in the non-planting state, and stops or stops the leveling height control.

  Specifically, as shown in FIG. 6, the surface height detection means 160 includes a detection body 167 and a sensor main body 168 described later, and the detection body 167 rotates up and down around the support rod 166. Then, the rotation angle of the support rod 166 is detected by the sensor body 168. When the detection body 167 that rotates downward by its own weight around the support rod 166 rotates downward by a predetermined angle or more, the sensor main body 168 detects the downward rotation angle and uses the detected information as control means. 53. When the control unit 53 acquires the detection signal, the control unit 53 recognizes (determines) that the planting unit 2 is in the non-planting operation state (non-grounding mode), and performs leveling height control of the leveling device 4. Stop or stop.

  That is, when the sensor body 168 detects a suspended state (non-contact state with the surface Fs) due to the weight of the detection body 167, the control unit 53 causes the planting unit 2 to perform non-planting work based on the detection information. Recognizing the state (non-grounding mode), the leveling height control of the leveling device 4 is stopped or stopped. On the other hand, when the detection body 167 comes into contact with the field surface Fs, the downward rotation of the detection body 167 is suppressed to be less than a predetermined angle by the vertical drag from the field surface Fs. In this case, the control unit 53 recognizes that the planting unit 2 is in the planting work state (grounding mode) based on the detection information of the sensor body 168, and starts or continues the leveling height control of the leveling device 4. To do. As described above, as the second work state detection means, the plant height detection means 160 is used to detect the planting work state, so that a sensor dedicated to the work state detection is not required and the manufacturing cost is reduced. Can be reduced.

  The third work state detection means is a float load detection sensor 180 shown in FIG. The float load detection sensor 180 is attached to a pair of left and right float support arms 122 that connect and support the floats 35 and 36 via pivot brackets 123 shown in FIG. It is a detection means to detect. As the float load detection sensor 180, a load cell or the like can be used. When the float load detection sensor 180 connected to the input side of the control means 53 detects the reduced float load and the control means 53 acquires the reduced detection information, the control means 53 2 is recognized as a planting work state (grounding mode). On the other hand, when the float load detection sensor 180 detects the increased / restored float load and the control means 53 acquires the increased / restored detection information, the control means 53 indicates that the planting unit 2 is not Recognizing that it is a planting work state (non-grounding mode), the leveling height control of the leveling device 4 is stopped or stopped.

  The fourth work state detection means is a lever detection sensor 182 shown in FIG. The lever detection sensor 182 is a detecting means such as a limit switch that is disposed in the vicinity of the elevating operation lever 72 that elevates the planting unit 2 and detects the elevating operation of the elevating operation lever 72. Then, when the lever detection sensor 182 is connected to the input side of the control means 53 and detects the raising operation of the elevating operation lever 72, the detection information is transmitted to the control means 53, and the transmission information is acquired by the control means 53. Then, the control means 53 recognizes that the planting part 2 is in the non-planting operation state (non-grounding mode), and stops or stops the leveling height control of the leveling device 4.

  The fifth work state detection means is a forward position detection sensor 184 shown in FIG. The forward position detection sensor 184 is a detection unit that detects the main transmission lever 70 inserted into the lever guide groove 71 only at the forward operation position. The forward position detection sensor 184 is connected to the input side of the control means 53, and when detecting the main speed change lever 70 at the forward speed change operation position, transmits the detection information to the control means 53 and controls the transmission information. When the means 53 acquires, the control means 53 recognizes that the planting part 2 is in the planting work state (grounding mode). When the forward position detection sensor 184 cannot detect the main shift lever 70 at the forward shift operation position, the non-detection information is transmitted to the control means 53, and the transmission information is acquired by the control means 53. Then, the control means 53 recognizes that the planting part 2 is in the non-planting work state (non-grounding mode), and stops or stops the leveling height control of the leveling device 4. At this time, the main transmission lever 70 is located at any one of the shift operation position other than the forward transmission operation position, the neutral transmission operation position, the reverse transmission operation position, or the seedling transmission operation position, and the forward position detection sensor 184. Cannot detect the main transmission lever 70.

  The sixth work state detection means is a rise detection sensor 186 shown in FIG. The rise detection sensor 186 is detection means such as a limit switch that detects the top link 40 of the lifting mechanism unit 3 when the lifting mechanism unit 3 is turned up and rotated. Then, when the rise detection sensor 186 is connected to the input side of the control means 53 and detects the top link 40 that has been raised and rotated, the detection information is transmitted to the control means 53, and the transmission information is transmitted to the control means 53. Upon acquisition, the control means 53 recognizes that the planting unit 2 is in the non-planting work state (the non-grounding mode) in which the planting unit 2 is placed up, and stops or stops the leveling height control of the leveling device 4. Further, the fifth work state detection means may be a lowering detection sensor such as a limit switch for detecting the top link 40 of the lifting mechanism unit 3 when the lifting mechanism unit 3 is rotated downward.

  The seventh work state detection means is a rotation angle detection sensor 188 shown in FIG. The rotation angle detection sensor 188 is detection means such as a torque limiter that detects a rotation angle (rotation operation angle) around the axis of the steering shaft 21 that supports the steering wheel 23. In other words, the rotation angle detection sensor 188 detects the rotation angle and detects the rotation angle when the steering shaft 21 is rotated in the left or right direction around the axis via the steering wheel 23. Is continuously transmitted to the control means 53. Then, when the steering shaft 21 is rotated (turned) by a predetermined angle θ (for example, 45 degrees) or more counterclockwise from the forward straight traveling position and more than a predetermined angle θ or counterclockwise, that is, the traveling unit 1 When the turning angle detection sensor 188 detects a large turning angle of the steering wheel 23 corresponding to the turning operation of the steering wheel 23 and the detected value is transmitted to the control means 53, the control means 53 that has acquired the detected value Recognizing that the part 2 has shifted to the non-planting operation (non-grounding mode), the leveling height control of the leveling device 4 is stopped or stopped.

  The eighth work state detection means is an engine stop detection sensor 189 shown in FIG. The engine stop detection sensor 189 is a detection means such as an engine speed sensor that detects the speed of the engine 20, and detects that the engine 20 has been stopped based on the engine speed. The engine stop detection sensor 189 detects the rotation speed of the crankshaft of the engine 20 (engine rotation speed) and continuously transmits the detection value to the control means 53. At this time, if the control means 53 obtains a detection signal indicating that the engine speed has become a low speed equal to or less than a certain value, the engine stoppage is stopped even before the rotation of the crankshaft of the engine 20 is stopped. (Enst), that is, the planting unit 2 recognizes that it is in the non-planting operation state (non-grounding mode), and stops or stops the leveling height control of the leveling device 4. In particular, if an engine stall occurs during the planting operation, the leveling height control of the leveling device 4 is stopped and the leveling height H1 of the leveling device 4 is maintained as it is. Can be resumed smoothly.

  In addition, the work state detection means for detecting the work state of the planting unit 2 that is interpreted in a broad sense is not limited to the first to eighth work state detection means described above.

[Specific Explanation of Each Means above]
Next, the configuration of the surface height detection means (field height detection sensor) 160 will be specifically described. That is, as shown in FIGS. 5 to 7, the surface height detection means 160 is attached to the front wall of the portion of the lower left and right extension piece 31 d located directly above the center float 35 via the detection means support 161. ing. The detection means support 161 has a fixed-side support piece 162 attached to the front wall of the lower left and right extending piece 31d, and a rear end of the movable-side support piece 164 via a pivot 163 having an axis line directed in the left-right direction to the fixed-side support piece 162. The movable support piece 164 is swingable up and down by pivotally supporting the part. A cylindrical pivot piece 165 having an axis line in the left-right direction is attached to the movable support piece 164.

  The surface height detection means 160 pivotally supports a central portion of a support rod 166 having an axis line in the left-right direction on the cylindrical pivot piece 165 so as to be rotatable forward and backward around the axis line. The base end portions of a pair of left and right detection bodies 167 and 167 are attached to the left and right end portions of the support rod 166, respectively, and the distal end portions of both detection bodies 167 and 167 are brought into contact with the surface Fs. A sensor main body 168 such as a potentiometer is attached to the movable support piece 164, and the rotation of the support rod 166 that rotates forward and backward in conjunction with the lifting and lowering operations of the two detection bodies 167 and 167 by the sensor main body 168 (change in rotation angle). It is configured to detect (amount). A detection value (detection information) detected by the sensor main body 168 is transmitted to the control means 53.

  Since the pair of left and right detectors 167 and 167 are similarly attached to the left and right ends of the support rod 166, only the attachment structure of the left detector 167 will be described below. That is, the detection body 167 is attached to the left end portion of the support rod 166 by fitting the cylindrical boss portion 176, and extends the detection arm 169 rearward and downward from the boss portion 176 to A horizontally long rectangular plate-shaped attachment plate 170 is attached to the end portion with its surface facing up and down, and the front edge portion of the bowl-shaped detection main body 171 is attached to the attachment plate 170. The detection main body 171 includes a plurality of (in this embodiment, six) rod-shaped detection main body forming pieces 172 bent in an L shape when viewed from the side, and is arranged at intervals in the left-right direction, and the front end of the detection main body forming piece 172 An integrally connecting piece 173 formed in a horizontally long plate shape in the left-right direction with the surface facing in the up-down direction is integrally connected to the edge. Then, the upper surface of the integral connecting piece 173 is superposed on the lower surface of the mounting plate 170 and is mounted with mounting bolts 174.

  The detection main body 171 is grounded in a line contact manner with the field surface Fs in the latter half part, and slides along the field surface Fs on the field surface Fs, and responds to the shape change of the field surface Fs and the lifting operation of the center float 35. To move up and down (oscillate). For example, when sinking to the surface Fs or floating in the surface water (when the surface water is stretched), the detection body 171 is swung up and down in the opposite direction, and the support rod 166 rotates forward and backward. Is done. The sensor body 168 detects the amount of change in the rotation angle of the support rod 166 at that time, thereby detecting the vertical swing angle of the detection body 171 and transmitting the detection result to the control means 53. The control means 53 calculates the field height H4 from the acquired detection result. Then, as described above, the subsidence amount H5 of the center float 35 (the subsidence amount to the mud-like field surface Fs) can be measured from the calculated value of the surface height H4.

  The detection main body forming piece 172 is formed in an elongated shape to reduce the contact area between the field surface Fs and the surface water (when the surface water is stretched), thereby reducing the resistance of the detection main body formation piece 172 to the surface Fs, The detection main body forming piece 172 is difficult to be separated from the field surface Fs. The detection main body forming piece 172 is formed of a plurality of rods and is formed in a rake shape, thereby preventing impurities from being caught in the detection main body forming piece 172. As a material constituting the detection main body forming piece 172, a material such as a wire having a strength that can hold the shape with respect to a desired length is suitable. A suitable length of the detection main body forming piece 172 is, for example, such that the detection main body forming piece 172 extends above the surface water in a state where the detection main body forming piece 172 is in contact with the field surface Fs. The detection arm 169 can be provided with a regulating member (not shown) that regulates the downward rotation angle of the detection body 171 to limit the rotation range of the detection body 171. By doing so, the detection main body 171 can be reliably separated from the ground when the planting part 2 is raised.

[Description of Center Float 35]
As shown in FIG. 6, the center float 35 includes a front part 35 a formed in a left and right horizontally long rectangular plate shape, and a rear part formed in a front and rear vertical rectangular plate shape extending rearward from the center part of the rear end edge of the front part 35 a. 35b. The left and right widths of the rear part 35b are formed narrower than the left and right widths of the rear edge of the front part 35a, and the corners formed by the right and left parts of the rear edge of the front part 35a and the left and right side edge front parts of the rear part 35b. The detection main body 171 is disposed in the part 175. That is, the detection main body 171 is slid on the field surface Fs after the left and right sides of the front part 35a slide, and the seedling N is planted on the field surface Fs by the planting claws 34 behind the detection main body 171. The main body 171 is configured to perform a detection function steadily.

[Description of structure related to planting depth control]
The planting part 2 enables the planting depth control for maintaining the planting depth setting height H2 by the elevating mechanism part 3 through the control means 53, and the structure relating to this planting depth control is described below. This will be specifically described.

  That is, as shown in FIGS. 10 to 12, the planting part 2 pivotally supports a float support shaft 121 extending in the left-right direction below the planting transmission case 30 so as to be rotatable about its axis. . A base end portion (front end portion) of a pair of left and right float support arms 122 extending in the front-rear direction is connected to the float support shaft 121 at intervals in the left-right direction, and a distal end portion (rear end portion) of the float support arm 122 is provided. ) Are pivotally connected by pivots 124 having the axis line in the left-right direction through the pivot brackets 123. The front end portion and the rear end portion of the center float 35 and the side float 36 are supported so as to be swingable in the vertical direction around the axis of the pivot 124. In the middle of the float support shaft 121, a lower end portion of the planting depth setting lever 125 is fixed, and the planting depth setting lever 125 is extended forward and upward. The part is composed.

[Description of Configuration of Planting Depth Setting Unit 193]
The planting depth setting means 193 is configured so that the center float 35 and the side float 36 can be set to a set planting depth. That is, as shown in FIGS. 10, 13, and 14, the planting depth setting lever 125 is passed through a vertically long rectangular opening 127 formed in the front surface portion of the lever guide body 126 and projected forward and upward. At the same time, it is possible to set the planting depth by manual operation by grasping the tip. The lever guide body 126 is formed of a front surface portion and left and right side surface portions extending rearward and downward from left and right side edge portions of the front surface portion. Then, a guide body support arm 143 is provided on the lower left and right extended piece 31d of the planting frame 31 so as to project forward and upward, and the lever guide body is formed by the tip of the guide body support arm 143 and the upper surface portion of the lower left and right extended piece 31d. 126 is supported. A pair of left and right slide guide pieces 128, 128 are attached to the back side of the opening 127 of the lever guide body 126, and the rectangular plate-like slide body 129 is slidable vertically between the slide guide pieces 128, 128. It is arranged. In the slide body 129, a horizontally long locking groove 131 for locking the locking piece 130 provided at the base of the planting depth setting lever 125 is formed in multiple stages in the vertical direction, and the left end of the locking groove 131 is formed. A lever guide groove 132 that extends in the vertical direction and communicates with the left end portion of each locking groove 131 is formed in the portion.

  A planting depth setting motor 191 is disposed on the upper left side of the lever guide body 126, and the planting depth setting motor 191 is provided with an upper end portion of a slide support shaft 133 extending in an up-down direction and extending in an interlocking manner. The slide support shaft 133 is arranged behind the front surface of the lever guide body 126. A slide ring 134 is fitted on the outer peripheral surface of the slide support shaft 133, and the slide ring 134 can be moved up and down along the axis of the slide support shaft 133 in conjunction with the rotation of the slide support shaft 133. Yes. A slide body 129 is connected to the slide ring 134 so that the slide body 129 moves up and down integrally with the slide ring 134. A set planting depth detecting means 135 such as a potentiometer is attached to the left side surface portion of the lever guide body 126.

  The set planting depth detection means 135 includes a detection main body 136 and a detection terminal 137 attached to extend from the detection main body 136 to the front, and an engagement piece 138 attached to the proximal end portion of the planting depth setting lever 125. The detection terminal 137 is engaged in an orthogonal state from above. And the detection main body 136 detects the amount of vertical rotation displacement of the planting depth setting lever 125 through the engagement piece 138 and the detection terminal 137 engaged in the orthogonal state. The detection main body 136 transmits a detection value (detection information) to the control means 53. When the upper and lower limit stop sensors 139, 140 such as limit switches are provided on the left side surface of the lever guide body 126, and the action pin 141 protruding from the slide ring 134 acts on any of the sensors 139, 140, By stopping the planting depth setting motor 191, the sliding operation of the slide ring 134 is stopped and restricted at the upper limit position or the lower limit position.

  A lever support 142 protrudes forward in the middle of the float support shaft 121. The lever support 142 protrudes forward and upward, and is bent from the middle and protrudes forward. . On the upper surface of the lever support 142, the base end portion of the planting depth setting lever 125 is superposed vertically. The planting depth setting lever 125, the lever support 142, the float support shaft 121, and the float support arm 122 are integrally connected. Reference numeral 144 denotes an actuator cover.

  With this configuration, when the planting depth setting lever 125 is rotated upward (downward) about the axis of the float support shaft 121, the float support arm 122 opposes the downward (upward) direction. The center float 35 and the side float 36 connected to the float support arm 122 are moved up and down. That is, the float support shaft 121 is pivotally operated by the planting depth setting lever 125 with the fulcrum support shaft 121 as a fulcrum, so that the axial center position (center float 35 and side float 36) of the pivot 124 is changed in the vertical direction. Thus, the planting depth setting height H2 (setting depth) can be changed. At this time, the planting depth setting lever 125 is slid in the vertical direction along the lever guide groove 132, and is locked in the locking groove 131 of the desired slide body 129 via the locking piece 130. The axial center position (the center float 35 and the side float 36) of the pivot 124 can be fixed, and the center float 35 and the side float 36 can be set to the planting depth setting height H2 (set depth).

  When the planting depth is set by the planting depth setting operation unit 190, the control unit 53 controls the planting depth setting motor 191 via the set planting depth detection unit 135. In other words, the slide ring 134 and the slide body 129 connected thereto are integrally moved up and down along the axis of the slide support shaft 133 that is linked to the planting depth setting motor 191, and the locking groove 131 of the slide body 129 is controlled. The planting depth setting lever 125 that is set via the locking piece 130 that is locked to is rotated (finely adjusted) appropriately in the vertical direction so that the center float 35 and the side float 36 set the planting depth. Arranged at height H2. In this way, the center float 35 and the side float 36 are finely moved from the position set by the planting depth setting lever 125 to the official set position by the planting depth setting motor 191 via the set planting depth detection means 135. Adjusted.

  As shown in FIG. 6, the center float 35 pivotally connects the lower end portion of the connecting rod 146 to the front end portion thereof via a connecting piece 145, and the upper end portion of the connecting rod 146 is interlocked to the planting depth interlocking mechanism 147. doing. The planting depth interlocking mechanism 147 has a fixed body 148 attached to the front wall in the middle of the lower left and right extending piece 31d, and is formed in a side-view shape through a pivot 149 having an axis line in the left-right direction. The bent portion of the body 150 is pivotally supported, and the connecting body 152 is connected to the front end portion of the movable body 150 via the connecting pin 151, while the lower end portion of the movable body 150 is connected to the float support shaft 121 via the interlocking rod 153. A standing interlocking arm 154 is connected. A swing support shaft 155 having an axis line in the left-right direction is pivotally supported on the connecting body 152, and a base end portion (rear end portion) of the vertical swing arm 156 is connected to the left end portion of the swing support shaft 155. The upper end portion of the connecting rod 146 is connected to the tip end portion (front end portion) of the vertical swing arm 156. As shown in FIG. 12, a float angle detecting means 157 such as a potentiometer for detecting the swing angle (swing displacement amount) of the swing support shaft 155 is attached to the right side of the connecting body 152 to detect the float angle. The means 157 can detect a float angle indicating the vertical posture of the center float 35 (an elevation angle or a depression angle of the center float 35 swinging in the vertical direction around the pivot axis 124). The detection information (detection value) of the float angle detection unit 157 is transmitted to the control unit 53.

  With this configuration, when the planting depth setting operation is performed, the planting depth interlocking mechanism 147 is interlocked with the rotation operation of the float support shaft 121 around its axis, and the front end portion of the center float 35 is set to the set planting. Raised and lowered to depth. That is, when the planting depth is set for the rear part of the center float 35, the front end of the center float 35 is moved up and down in conjunction with the center float 35 so as to be held substantially horizontally at the planting depth setting position. And when this planting depth setting operation has been performed, when the front end of the center float 35 is moved up and down, or when the front end of the center float 35 is moved up and down according to the change in the field surface Fs, The swing support shaft 155 is swung via the connecting rod 146 and the vertical swing arm 156, the swing displacement amount is detected by the float angle detecting means 157, and the detected value is transmitted to the control means 53. The

  The float angle detection means 157 can detect the posture of the center float 35 as described above. For example, the detection value of the float angle detection means 157 is the planting depth setting height set by the planting depth setting operation means 190. If the detected value does not match the set value corresponding to the height H2 (set depth), for example, the control means 53 controls the control valve 53 so that the bottom surface of the center float 35 is horizontal so that the detected values match. The planting part 2 is lifted and lowered by the lift cylinder 43 via 44.

  That is, while the center float 35 follows the ground surface Fs in contact with the ground surface Fs, when the planting unit 2 moves up and down following the change in the posture of the traveling unit 1, the planting unit 2 extends from the surface Fs accordingly. (The planting depth H3 of the seedling N by the planting claw 34) may change. Then, a change in the height from the field surface Fs to the planting part 2 (planting depth H3 of the seedling N by the planting claw 34) is detected by the float angle detecting unit 157, and the detection value of the float angle detecting unit 157 is detected. Is set to the set detection value (planting depth setting height H2 (setting planting depth)), the control valve 44 for supplying and discharging hydraulic oil to and from the elevating cylinder 43 is controlled by the control means 53. The planting part 2 is driven up and down, and the planting depth H3 of the seedling N by the planting part 2 (planting claw 34) is maintained at the set depth. This is the planting depth control.

  Further, the surface height detection means 160 detects that the center float 35 is in a subsidence state with respect to the field surface Fs, and the float angle detection means 157 indicates that the float angle of the center float 35 forms an elevation angle (a depression angle). Is detected, the control means 53 determines that the soil of the field G is hard (soft), and controls the leveling device 4 to the lowering (upward) side.

  The above-described planting depth setting means 193 has a planting depth setting lever 125 that is manually operated. FIGS. 15 and 16 show a modification of the planting depth setting means 193. Without providing the height setting lever 125, the planting depth is automatically set only by knob-rotating the planting depth setting operation means 190.

  That is, the planting depth setting means 193 as a modification has the same basic structure as the planting depth setting means 193 described above, but without setting the planting depth by the planting depth setting means 193, The difference is that the planting depth can be set by the depth setting operation means 190.

  Specific differences are as follows. That is, as shown in FIGS. 15 and 16, the base end portion (rear upper end portion) of the rod-shaped first interlocking piece 200 that extends forward and downward is attached to the front end portion of the lever support 142, and The second interlocking piece 201 is provided at the front end portion (front lower end portion) so as to project toward the slide support shaft 133, while the second interlocking piece 201 is connected to the slide support shaft 133 from the slide ring 134 that is externally fitted to the first interlocking piece. The second interlocking piece 201 and the third interlocking piece 202 are connected by projecting a third interlocking piece 202 on the 200 side. An engagement piece 138 is attached to the slide ring 134, and the detection terminal 137 of the set planting depth detection means 135 is engaged with the engagement piece 138 in an orthogonal state from above. The detection main body 136 detects the amount of vertical sliding displacement of the slide ring 134 via the engagement piece 138 and the detection terminal 137 engaged in the orthogonal state.

  In this way, when the planting depth is set by the planting depth setting operation unit 190, the control unit 53 controls the planting depth setting motor 191 via the set planting depth detection unit 135. Yes. That is, the slide ring 134 is controlled to move up and down along the axis of the slide support shaft 133 that is interlocked and connected to the planting depth setting motor 191, and the lever support 142 is moved via the first to third interlocking pieces 200 to 202. Up and down rotation control is performed with the float support shaft 121 as a fulcrum. The float support arm 122 moves up and down in the opposite direction in conjunction with the up and down rotation of the lever support 142 so that the center float 35 and the side float 36 are arranged at the planting depth setting height H2. Yes. Reference numeral 158 denotes a non-rotating piece protruding from the slide ring 134, and 159 denotes a non-rotating groove formed in the lever guide body 126 for inserting the non-rotating piece 158 to prevent the slide ring 134 from rotating. Reference numeral 177 denotes a support body supporting piece that supports the lower end portion of the slide support body 133 so as to be rotatable about its axis.

[Specific Description of Configuration of Leveling Device 4]
Next, each means 50-53 which comprises the leveling apparatus 4 is demonstrated more concretely. That is, as shown in FIGS. 1 to 3, the leveling means 50 includes a rotor gear case 60 and a pair of leveling rotors 61 and 61 disposed on the left and right sides of the rotor gear case 60. In the rotor gear case 60, there are disposed an input shaft 60a having an axis directed forward and left and right output shafts 60b, 60c directed axially rearward and outward, and a distal end portion (front end portion) of the input shaft 60a. The rear end of the leveling shaft 54 is detachably connected to the base end (rear end) of the input shaft 60a, and the base ends of the left and right output shafts 60b and 60c are connected to each other via a gear. ing.

  The leveling rotor 61 is configured by coaxially attaching a large number of rotor forming pieces 63 to an outer peripheral surface of a rotor shaft 62 extending in the left-right direction with its axis line directed. As shown in FIG. 2, the rotor forming piece 63 is formed so as to be fitted on the outer peripheral surface of the rotor shaft 62 formed in a rectangular cylindrical shape, and protruded in the radial direction from the outer peripheral surface of the boss portion 64. A plurality of (six in this embodiment) support pieces 65 formed at equal intervals in the circumferential direction, and a leveling piece 66 formed integrally with the tip of each support piece 65 by extending in the axial direction. Formed from. The inner ends of the rotor shafts 62 and 62 are interlocked and connected to the front ends of the left and right output shafts 60b and 60c, respectively, and the rotor shafts 62 and 62 are arranged on the extension lines of the axis of the output shafts 60b and 60c. ing. That is, the rotor shafts 62 and 62 are extended rearward and outward about the rotor gear case 60. The leveling pieces 66 adjacent to the left and right are arranged in alignment in the axial direction, and rotate integrally around the outer periphery of the rotor shaft 62 in conjunction with the rotor shaft 62 so as to level the surface Fs. Yes.

  A plate-like connecting body 67 is attached to the upper wall of the rotor gear case 60 in a superposed state, and the left side of the tubular shape extending to the rear left side along the left rotor shaft 62 is attached to the rear portion of the connecting body 67. The frame 68 is connected to the inner end of a right tubular frame 68 that extends parallel to the right rotor shaft 62 and extends toward the rear right side. A rotor cover 69 that covers the upper and rear portions of the leveling rotor 61 is attached to each frame 68.

  As shown in FIGS. 17 to 21, the vertical position adjusting means 52 has a rotary shaft 80 that is stretched in the left-right direction so that it can freely rotate in the forward and reverse directions, and upper ends of the rotary shaft 80 are linked to both ends. A pair of left and right vertical movement mechanisms 81 that move up and down in conjunction with forward and reverse rotations of the rotation axis, and a rotary shaft 80 for adjusting the vertical position of the leveling means 50 installed between the lower ends of both vertical movement mechanisms 81 are provided. And an electric motor 82 that can be driven to rotate in the forward and reverse directions. Thus, by rotating the rotary shaft 80 forward and backward by the electric motor 82 controlled by the control means 53, the leveling means 50 can be adjusted in the vertical position via the pair of left and right vertical movement mechanisms 81, and the leveling is adjusted. The height H1 (see FIG. 2), that is, the height from the field surface Fs to the lowest end of the leveling rotor 61 can be steadily controlled with a simple structure. The actuator is not limited to the electric motor 82, and an electric or hydraulic cylinder can be used as appropriate. L is an imaginary front and rear extension line.

  More specifically, the middle part left and right stretched piece 31b is horizontally placed between the middle part of the pair of left and right vertically stretched pieces 31a and 31a forming a part of the planting frame 31, and the middle part left and right stretched piece 31b is left and right. A pair of shaft support pieces 31c, 31c are suspended, and a rotary shaft 80 having an axis line in the left-right direction is horizontally suspended between the shaft support pieces 31c, 31c so as to be rotatable about the axis line. The pair of left and right vertical movement mechanisms 81 and 81 are attached to the left and right side portions of the rotating shaft 80 with the base end portions of the pair of left and right upper arms 84 and 84 projecting forward, while the pair of left and right vertical extending pieces 31a and 31a. A pair of left and right pivot pieces 83, 83 project forward from the lower left and right extending pieces 31 d that support the lower parts of the left and right pairs, and a pair of left and right lower arms 85 projecting forward from the pivot pieces 83, 83. The proximal end of 85 is pivoted. The upper end portions (front end portions) of the upper arms 84, 84 are connected to the upper end portions of a pair of left and right vertical movement rods 86, 86 extending in the vertical direction, and the front end portions (front end portions) of the lower arms 85, 85. ) Is connected to the lower part of each vertical movement rod 86, 86.

  The upper and lower rods 86 and 86 are connected to the upper arms 84 and 84 so that the upper and lower sliding motions are interlocked with the upper and lower swinging motions of the upper arms 84 and 84 and the lower arms 85 and 85 forming a parallel link. It is supported by the lower arms 85 and 85. Ring-like pivot support pieces 87, 87 are provided at the lower end portions of the vertical movement rods 86, 86, and the respective pivot support pieces 87, 87 are pivotally supported through the outer portions of the rotor shafts 62. 88 is a mud plate for preventing mud splashed by the rear wheel 14 from being placed on each of the floats 35, 36, and 36 disposed behind it, and 89 is a space between the frame 68 and the vertically moving rod 86. This is a reinforcing cable staying material interposed between the two.

  A cylindrical sector gear boss 90 is rotatably fitted on the right side of the rotary shaft 80, and the base end of the sector gear 91 is connected to the outer peripheral surface of the sector gear boss 90. The teeth of the sector gear 91 are arranged on a virtual circumference centered on the axis of the sector gear boss 90. A plate-like support side wall 92 is attached to the planting frame 31 so as to be adjacent to the sector gear 91 in a parallel state, and is extended to the left from the upper end edge and the front end edge of the support side wall 92 to form an upper surface forming body 93. And a front surface forming body 94 are formed. An actuator 82 such as an electric motor is attached to the front surface forming body 94 via a bracket 95, and a pinion gear case 96 is attached to the actuator 82. A pinion gear 96 a is attached to the drive shaft 82 a of the actuator 82, and the pinion gear 96 a is disposed in the pinion gear case 96.

  The pinion gear 96a is engaged with the sector gear 91. 97 is a movable side connecting piece that extends rearward and downward from the sector gear 91, 98 is a fixed side connecting piece that extends rearward and downward from the front surface forming body 94, and 99 is a space between the movable side connecting piece 97 and the fixed side connecting piece 98. The sector gear 91 is urged to rotate clockwise as viewed from the left side by the tension spring 99 via the movable connecting piece 97. With this configuration, the sector gear 91 can be rotated forward and backward via the pinion gear 96a by rotating the drive shaft of the actuator 82 forward and backward.

  An interlocking body 100 formed in a gate shape so as to straddle the sector gear boss portion 90 is attached to the rotating shaft 80. That is, the interlocking body 100 includes arm pieces 101 and 101 that are fixedly attached to the rotation shaft 80 and extend forward and upward from the upper end portion of the sector gear 91, and both arm pieces 101. , 101 is formed in a gate shape from the horizontal piece 102 laid between the two, 101 to avoid interference with the sector gear 91. An engagement recess 103 is formed at the tip of the front edge of the right arm piece 101, and an engagement pin 104 is projected from the upper end of the sector gear 91 toward the right side. The engaging recess 103 is brought into contact with each other. A torsion coil spring 105 is wound around the outer peripheral surface of the sector gear boss 90, and one end of the torsion coil spring 105 is engaged with the lower edge of the sector gear 91, while the other end of the torsion coil spring 105 is connected to the left arm piece 101. The torsion coil spring 105 is engaged with the rear end edge and elastically biased in the direction in which the engagement pin 104 and the engagement recess 103 abut.

  With this configuration, the rotary shaft 80 is rotated forward and backward via the interlocking body 100 in conjunction with forward and reverse rotation of the sector gear 91. The vertical movement of the pair of left and right upper arms 84, 84 is linked to the forward / reverse rotation of the rotary shaft 80, and the vertical movement of the pair of left and right vertical movement rods 86, 86 is linked to the vertical movement of the upper arms 84, 84. In conjunction with each other, the leveling rotors 61 and 61 pivotally connected to the lower end portions of the vertically moving rods 86 and 86 via pivot support pieces 87 and 87 can be adjusted in the vertical position. Further, since the rotary shaft 80 is urged so as to rotate downward by the torsion coil spring 105, even when the leveling rotor 61 vigorously abuts against the convex portion, the leveling rotor 61 bounces upward. Without passing, it will descend quickly after passing the convex part. Further, when a sudden load is applied to the leveling rotors 61, 61 upward from below by the convex surface of the surface Fs or foreign matter, the vertically moving rods 86, 86 → the upper arms 84,84 → the rotating shaft 80 → The load is propagated to the interlocking body 100 so that the interlocking body 100 is rotated clockwise in the left side view against the elastic biasing force of the torsion coil spring 105. That is, as shown in FIG. 20, the interlocking body 100 is rotated in a direction away from the sector gear 91 so as to function as a limiter that prevents a load from acting on the actuator 82 via the sector gear 91. Yes.

  A sector gear detection body 110 such as a potentiometer, which is an adjustment operation detecting means for detecting the rotation operation of the sector gear 91, is attached to the upper portion of the support side wall 92. The sector gear detector 110 has a detection terminal 112 projecting from the detection body 111 toward the engagement pin 104, and the lower end edge of the detection terminal 112 is urged into contact with the peripheral surface of the engagement pin 104. ing. When the sector gear 91 is rotated in the forward / reverse direction, the detection terminal 112 is interlocked via the engagement pin 104 so that the sector gear detector 110 detects the forward / reverse rotation angle of the sector gear 91 via the detection terminal 112. I have to.

  The control means 53 transmits a control signal to the actuator 82 based on the detection result acquired from the sector gear detector 110 to stop the rotation of the actuator 82. In this way, the height (leveling height) of the leveling rotor 61 from the field surface Fs is appropriately controlled, that is, leveling height control is performed.

[Elevation control structure as another embodiment of the vertical position adjusting means 52]
FIG. 22 shows a lifting control structure as another embodiment of the vertical position adjusting means 52. This vertical position adjusting means 52 has the same basic structure as the leveling device 4 described above, but has a float support shaft. The difference is that the leveling height H1 can be changed in conjunction with the amount of displacement of the forward / reverse rotation angle of 121 around the axis, and the sector gear detector 110 is not provided.

  That is, as shown in FIG. 22, the vertical position adjusting means 52 has a swinging body support tube 210 rotatably fitted on the right side portion of the rotating shaft 80, and the front end portion of the interlocking swinging body 211 on the swinging body support tube 210. Is attached. On the other hand, on the right side of the float support shaft 121, an operating arm 212 is provided so as to protrude rearward. An interlocking connecting rod 213 extending in the vertical direction is interposed between the front end (rear end) of the operating arm 212 and the rear end of the interlocking rocking body 211. A swing detection body 214 such as a potentiometer is attached to the interlocking swing body 211, and a detection terminal 216 protruding from the swing detection body 214 is engaged with an engagement pin 215 protruding from the rotation shaft 80. The swing detector 214 is electrically connected to the control means 53. An electric cylinder as an actuator may be employed instead of the electric motor 82. For example, a push-pull wire may be employed instead of the interlocking connecting rod 213 as long as it has a function of physically transmitting the pushing / pulling force.

  In the ground leveling device 4 configured as described above, when the float support shaft 121 is rotated when the planting depth is changed, the pivoting operation is performed via the operating arm 212 and the interlocking connecting rod 213. The moving body 211 is swung in conjunction with it.

  FIG. 24 shows a traveling unit 1 as another embodiment. The traveling unit 1 has the same basic structure as the traveling unit 1 of the above-described embodiment, but does not include a transmission mechanism case 27. It is different. That is, the rear axle case 15 is linked and connected to the terminal end portion (rear end portion) of the transmission shaft 19, and the start end portion (front end portion) of the leveling transmission shaft 54 is linked and connected to the rear axle case 15. The rear axle case 15 is provided with a clutch (not shown) for connecting / disconnecting power to the leveling shaft 54, and this clutch may be mechanically connected / disconnected. In addition, it is possible to adopt a form of connecting / disconnecting electrically.

A rice transplanter 1 traveling unit 2 planting unit 3 lifting mechanism unit 4 leveling device 50 leveling unit 52 vertical position adjusting unit 53 control unit

Claims (3)

A ground working unit is attached to the rear of the traveling unit via an elevating mechanism unit so that the ground working unit can be raised and lowered, and a ground leveling device for leveling a farm scene is disposed between the traveling unit and the ground working unit. An agricultural machine that can adjust the leveling height by adjusting the vertical position by means of vertical position adjustment means,
A farm scene height detecting means for detecting a farm scene height which is a height from a predetermined position of the ground working unit to the farm scene;
Working state detecting means for detecting the working state of the ground working unit;
While connecting these detection means to the input side, the control means connected the vertical position adjustment means to the output side,
With
When the work state of the ground working unit is detected by the work state detection means, the leveling device controls the leveling height via the vertical position adjustment means based on the detection value detected by the field scene height detection means. And configured to be
A farm machine characterized in that the leveling height control of the leveling device is stopped when the work state of the ground work unit is not detected by the work state detection means.   The work state detection means is a float angle detection means for detecting a float angle, and the float angle detection means constitutes a part of the control mechanism so that the work depth by the ground work section is maintained at the set depth. The agricultural machine according to claim 1, wherein   The work state detection means is a field scene height detection means for detecting the field scene height by touching the field scene, and the field scene height detection means constitutes a part of the control mechanism. The agricultural machine according to claim 1, wherein

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