JP2012249616A - Rice planting machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rice planting machine, which allows real-time acquisition of a soil condition or planting depth.SOLUTION: The rice planting machine includes a planting unit, a soil reaction detection device, and a control unit. The planting unit performs planting of seedlings by driving a planting claw. The soil reaction detection device includes a soil reaction detection unit which detects a soil reaction received from the soil for every planting of seedlings by the planting claw, and a rotary phase detection unit which detects a rotary phase of the planting claw. The control unit calculates a planting depth value based on the soil reaction and rotary phase (S102). The control unit performs raising/lowering control of the planting unit based on the detected planting depth value (S109).

Description

  The present invention mainly relates to a rice transplanter. In detail, it is related with the structure for controlling correctly the planting depth of the seedling by a rice transplanter.

  In the rice transplanter, the structure which raises / lowers a planting part up and down is known (for example, patent document 1).

  One of the purposes of vertically controlling the planting part is to keep the seedling planting depth constant. That is, the distance between the ground and the planting part constantly varies depending on the unevenness of the ground, the pitching / rolling behavior of the vehicle body, and the like. Therefore, if the position of the planting part is fixed, the planting depth of seedlings varies, so that not only clean planting is possible, but also problems such as floating seedlings may occur. In order to prevent this, the planting depth of the seedling is kept constant by controlling the planting part up and down by following the ground.

  As disclosed in Patent Document 1, the conventional rice transplanter controls the raising and lowering of the planting unit based on the rocking angle of the float included in the planting unit. That is, the float is swingably attached to the planting portion and is arranged so as to be in contact with the ground. The swing angle of the float changes as the planting part moves up and down relative to the ground. Therefore, it can be considered that the rocking angle of the float indicates the relative position of the planting part with respect to the ground. By controlling the planting part to keep the float swing angle constant, the planting part height relative to the ground can be kept substantially constant, so that the planting depth (planting depth) is approximately Planting can be carried out while keeping constant.

JP 2008-212059 A

  By the way, in the structure which raises / lowers a planting part based on a float rocking angle like patent document 1, there existed a problem that a planting depth could not be controlled correctly. That is, since the float is configured to come into contact with the ground over a relatively large area, the planting part position (relative position of the planting part with respect to the ground) obtained based on the rocking angle of the float is an average. It has been Therefore, when the change in the unevenness of the farm field is large, the planting part cannot be made to follow the ground with high accuracy by the lifting control by the swing angle of the float.

  Moreover, the structure which raises / lowers a planting part based on a float rocking | fluctuation angle like patent document 1 has the problem that it is easy to receive to the influence of agricultural field conditions (for example, soil hardness etc.). That is, even if the planting part is controlled to move up and down so that the rocking angle of the float is kept constant, the depth at which the seedlings are planted changes if the soil hardness is different. Therefore, in order to obtain a desired planting depth with a conventional rice transplanter, it is necessary for the operator to finely adjust the setting according to soil conditions. However, the adjustment work requires experience and intuition, and there are many cases where seedlings cannot be planted at a desired planting depth.

  This invention is made | formed in view of the above situation, The main objective is to provide the rice transplanter which can perform suitable planting according to soil conditions.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

  According to the viewpoint of this invention, the rice transplanter of the following structures is provided. That is, this rice transplanter is provided with a planting part position acquisition means and a control part. The planting part position acquisition means is for detecting a planting part position indicating a relative position of the planting part with respect to a certain point on the ground. The said control part raises / lowers the said planting part based on the detected planting part position.

  In this way, the planting unit can be made to accurately follow the ground by controlling the planting unit to move up and down based on the relative position of the planting unit with respect to a certain point on the ground. Seedlings can be planted at depth.

  The rice transplanter is preferably configured as follows. That is, the planting part position acquisition means, a soil reaction force detection unit that detects the soil reaction force that the planting unit receives from the soil each time the planting claw provided in the planting unit plant a seedling, And a phase detector for detecting the rotational phase of the planting claw. The said control part detects the said planting part position based on the said soil reaction force and a rotation phase.

  Thus, it becomes possible to detect a planting part position in real time by detecting the soil reaction force generated in the planting nail and the phase of the planting nail when the soil reaction force is generated. Therefore, stable and accurate planting can be implemented.

  In the rice transplanter described above, it is preferable that the control unit compares the detection value of the planting unit position with a target value of the planting unit position to adjust sensitivity of the elevation control.

  Thereby, the sensitivity adjustment which was conventionally performed manually for each field condition can be automatically performed.

  In the rice transplanter, the control unit may notify that an abnormality has occurred when a difference between the detected value of the planting unit position and the target value of the planting unit position exceeds a predetermined threshold. preferable.

  Thereby, an operator can recognize planting abnormality in real time.

  The rice transplanter is preferably configured as follows. That is, the rice transplanter includes a float that is swingably attached to the planting portion and that can contact the ground, and a float sensor that detects the swing angle of the float. And the said control part raises / lowers the said planting part based on the detected value of the said planting part position, and the output value of the said float sensor.

  The planting part position information is discrete information that can only be obtained when the planting nail has planted the seedling. Therefore, if control is performed only based on the information on the planting part position, a control delay or the like occurs. There is a case. Therefore, problems such as control delay can be avoided by using together the output of the float sensor that can obtain information continuously.

  In the rice transplanter, the control unit adjusts the target value of the swing angle of the float based on a result of comparing the detected value of the planting unit position and the target value of the planting unit position. It is preferable.

  Thereby, since the raising / lowering control by the float rocking | fluctuation angle which is easy to be influenced by the field conditions can be correct | amended with the information of a planting part position, the stable planting operation | work is attained continuously. Therefore, high robustness can be realized. Further, it is not necessary to manually adjust the float target angle according to the field conditions.

  In the rice transplanter described above, it is preferable that the control unit performs gain adjustment of the lifting control using the swing angle of the float based on the detected value of the planting unit position.

  In this way, by correcting the control gain of the lifting control based on the rocking angle of the float based on the detection value of the planting part position acquisition means, a more stable planting operation can be performed.

  Further, in the rice transplanter, the control unit, based on the detected value of the planting part position, the amount of nail protrusion of the planting claw from the surface of the float surface, the pressing load of the float against the ground, It is preferable to adjust at least one of them.

  Thus, by adjusting various items for controlling the rice transplanter based on the detected planting part position, the planting operation can be performed with higher accuracy.

The side view which shows the whole structure of the rice transplanter which concerns on one Embodiment of this invention. The top view of a rice transplanter. The side view which shows the rotation locus | trajectory of a planting nail | claw. The top view of a soil reaction force detection apparatus. (A) The graph which shows the example of the output waveform of a soil reaction force detection apparatus. (B) The graph which shows the signal which a rotation phase detection part and a bottom dead center detection part figure output. The flowchart of the raising / lowering control based on a planting depth value. The side view which shows the mode of the planting nail | claw vicinity of the rice transplanter which concerns on 2nd Embodiment. The flowchart of the raising / lowering control using a float angle and the planting depth value.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view of a riding type rice transplanter 1 according to an embodiment of the present invention.

  The rice transplanter 1 includes a vehicle body 2 and a planting unit 3 disposed behind the vehicle body 2.

  The vehicle body 2 includes a pair of left and right front wheels 4 and a pair of left and right rear wheels 5. Further, the vehicle body 2 includes a driver seat 6 between the front wheel 4 and the rear wheel 5 in the front-rear direction. In the vicinity of the driver seat 6, a steering handle 7 for performing a steering operation of the vehicle body 2, a shift pedal 8 for adjusting the traveling speed of the vehicle body 2, and other various operating tools are arranged.

  The vehicle body 2 includes a control unit (not shown). A control part consists of microcontrollers, for example, and is constituted so that each composition of rice transplanter 1 may be controlled based on signals, such as a sensor with which each part of rice transplanter 1 was equipped.

  Further, around the driver's seat 6, an unillustrated planting depth adjustment lever for setting the planting depth of the seedling is arranged. The operator can set the seedling planting depth by operating the planting depth adjusting lever. Further, a position switch that can detect the operation position of the planting depth adjustment lever is provided in the vicinity of the planting depth adjustment lever. The operation position of the planting depth adjustment lever detected by the position switch is output to the control unit. In the following description, the planting depth of the seedling set by the operator is called a target planting depth.

  In the vehicle body 2, an engine 10 is disposed below the driver seat 6, and a mission case 11 is disposed in front of the engine 10. On the other hand, on the rear side of the vehicle body 2, a lifting link mechanism 12 for attaching the planting unit 3, a PTO shaft 13 for outputting the driving force of the engine 10 to the planting unit 3, and driving the planting unit 3 up and down. The elevating cylinder 14 is arranged.

  The planting unit 3 includes a planting center case 15, a planting bevel case 24, and a seedling stage 17.

  A drive shaft (not shown) is disposed in the planting center case 15, and the drive force from the PTO shaft 13 is input to the drive shaft. As shown in FIG. 2, the rice transplanter of this embodiment has three planting bevel cases 24. The planting bevel case 24 is disposed along the longitudinal direction of the vehicle body and is arranged side by side in the lateral direction of the vehicle body. A drive shaft (not shown) is disposed in each planting bevel case 24, and a driving force from the planting center case 15 is input.

  The planting units 20 are attached to the left and right of each planting bevel case 24, respectively. Therefore, the rice transplanter 1 of this embodiment is configured as a six-row planting rice transplanter having six planting units 20. Each planting unit 20 is configured as a rotary planting device provided with two planting claws 22 in a rotating case 21. The driving force input to the planting bevel case 24 rotates the rotary case 21.

  Since the configuration of the rotary planting device is well known, detailed description will be omitted, but by rotating the rotary case 21, the tip of the planting claw 22 draws a loop-like locus as shown in FIG. However, it is configured to be driven up and down. When the tip of the planting claw 22 moves from top to bottom, one seedling 26 is scraped off from the lower end of a seedling mat 25 placed on a seedling platform 17 described later, and the root of the seedling 26 is collected. It is configured to move downward while being held and to be implanted in the ground.

  In the present specification, the distance from the bottom dead center of the tip of the planting claw 22 to the ground (the distance that the tip of the planting claw 22 enters the ground) is the “planting depth” in the sense of the depth of planting seedlings Call it.

  The seedling stage 17 is disposed above the planting bevel case 24. The seedling stage 17 is supported on a guide rail (not shown) so as to be slidable in the left-right direction of the vehicle body. The planting unit 3 includes a lateral feed mechanism (not shown) that reciprocates the seedling mounting table 17 left and right within the range of the left and right width of the seedling mat 25. Thereby, the seedling mat 25 placed on the seedling placing stand 17 can be moved relative to the planting unit 20 from side to side. In addition, the seedling mount 17 includes a seedling feeding belt (vertical feeding mechanism) that intermittently feeds the seedling mat 25 downward (that is, toward the planting unit 20 side). With the above configuration, by appropriately interlocking the horizontal feed mechanism and the vertical feed mechanism, seedlings can be sequentially supplied to each planting unit 20 and planted continuously.

  The lifting link mechanism 12 is connected to the planting center case 15. The elevating link mechanism 12 has a parallel link structure including a top link 18, a lower link 19, and the like. By driving the elevating cylinder 14 connected to the lower link 19, the planting center case 15 is moved up and down. It is comprised so that raising / lowering drive is possible (Thereby, the planting part 3 whole can be raised / lowered up and down).

  The driving of the elevating cylinder 14 is controlled by the control unit. A control part drives the raising / lowering cylinder 14, controls the planting part 3 to follow the unevenness | corrugation of the ground, and raises / lowers up and down so that a seedling can be planted with the target planting depth set by the operator.

  As described above, the conventional rice transplanter controls the planting unit 3 to move up and down based on the rocking angle of the float. However, as described above, since the float swings in contact with the ground over a relatively wide area, the planting part position (relative position of the planting part with respect to the ground) obtained from the swing angle of the float is It was not accurate. For this reason, in the conventional rice transplanter that controls the raising and lowering of the planting part using the swing angle of the float, it has been difficult to keep the height of the planting part constant by following the unevenness of the ground.

  Therefore, the rice transplanter 1 according to the present embodiment detects the relative position (planting part position) of the planting part with respect to a certain point on the ground and controls the planting part 3 to move up and down based on the detected planting part position. It is configured. In this way, by performing the elevation control based on the relative position of the planting unit 3 with respect to a certain point on the ground, it is possible to control to keep the planting depth constant regardless of the soil conditions.

  This will be described in detail below. The rice transplanter 1 according to the present embodiment includes a soil reaction force detection device (planting part position acquisition means) 27 as means for detecting the relative position of the planting part 3 with respect to a certain point on the ground. The soil reaction force detection device 27 is configured to detect a reaction force (soil reaction force) received from the soil when the planting unit 3 plants a seedling.

  The soil reaction force detection device 27 includes a soil reaction force detection unit that is disposed in the vicinity of the planting claw 22 and configured to rotate integrally with the planting claw 22. As shown in FIG. 4, the soil reaction force detection unit includes a load cell 28 and a probe 29.

  The load cell 28 has a known configuration that detects a load applied to the load detection surface and outputs a detection signal corresponding to the load. The detection signal of the load cell 28 is output to the control unit. As described above, since the soil reaction force detection device 27 rotates together with the planting claws 22, a signal from the load cell 28 to the control unit is output via the slip ring.

  The probe 29 is a rod-shaped member and is arranged so that its longitudinal direction is substantially parallel to the longitudinal direction of the planting claw 22. Further, the tip of the probe 29 faces the same direction as the planting claw 22 and is arranged so that the height from the ground is substantially the same as the tip of the planting claw 22. Since the probe 29 is arranged in this way, when the rotary case 21 is driven to rotate, the tip of the probe 29 and the tip of the planting claw 22 simultaneously move on substantially the same locus. The other end of the probe 29 is in contact with the load detection surface of the load cell 28. With this configuration, when a force is applied to the tip of the probe 29, the force is detected by the load cell 28, and the detection result is output to the control unit.

  In the soil reaction force detection device 27 configured as described above, the probe 29 is inserted into the ground almost simultaneously with the planting claw 22. Therefore, the load cell 28 detects substantially the same load as the reaction force (soil reaction force) that the planting claw 22 receives from the soil. In this way, the soil reaction force detection device 27 can detect the reaction force (soil reaction force) that the planting claw 22 receives from the soil.

  Further, the soil reaction force detection device 27 of the present embodiment is provided as a separate body from the planting claws 22. Therefore, the planting operation by the planting claws 22 is not likely to be inhibited by the soil reaction force detection device 27. Moreover, in this embodiment, the soil reaction force detection apparatus 27 is provided in the planting unit of the center vicinity in the vehicle body left-right direction, as shown in FIG. By arranging in this way, the influence of the rolling behavior of the vehicle body on the detection value of the soil reaction force detection device 27 can be reduced.

  In addition, the soil reaction force detection device 27 includes a rotation phase detection unit that detects the rotation phase of the planting claw 22 in order to acquire the generation timing of the soil reaction force detected by the soil reaction force detection device unit. . Specifically, the drive shaft in the planting bevel case 24 is provided with a rotation phase detector (not shown) for detecting the rotation phase of the drive shaft. The result detected by the rotational phase detector is output to the controller. Thereby, the control part can acquire the rotation phase of the planting claw 22.

  The rotational phase detector may be, for example, an absolute rotary encoder, but an inexpensive pickup sensor is used in this embodiment. However, since the pickup sensor only outputs a pulse signal corresponding to the rotational speed, the rotational phase of the planting claw 22 cannot be accurately detected only by the output of the pickup sensor. Therefore, in the rice transplanter 1 of the present embodiment, a bottom dead center detection unit that detects the bottom dead center of the planting claw 22 is provided on the drive shaft in the planting bevel case 24. The bottom dead center detection unit is configured to output a pulse signal to the control unit when the tip of the planting claw 22 reaches the bottom dead center.

  Next, a method for detecting the planting part position based on the detection result of the soil reaction force detection device 27 will be described.

  When the planting claw 22 is rotationally driven while drawing a loop-like locus as shown in FIG. 3, a detection waveform as shown in the graph of FIG. 5A is output from the soil reaction force detection device 27. That is, first, when the planting claw 22 scrapes off the seedling 26 from the seedling mat 25, the impact is detected as a reaction force. Next, the planting claw 22 holding the scraped seedlings moves downward, and the tip of the planting claw 22 collides with the ground. At this time, since the planting claw 22 receives a reaction force from the ground, the detection waveform output from the soil reaction force detection device 27 rises, and the soil reaction force increases until the planting claw 22 reaches the bottom dead center. When the planting claw 22 passes the bottom dead center, the detected soil reaction force starts to decrease. The planting claws 22 that have planted the seedlings 26 on the ground are pulled out from the ground. At this time, a pulling force (negative reaction force) is detected by the adhesive force of the ground.

  The control unit calculates the planting depth of the seedling based on the detection waveform of the soil reaction force output by the soil reaction force detection device 27 and the rotation phase of the planting claws 22. That is, the control unit refers to the outputs of the rotational phase detection unit and the bottom dead center detection unit, and acquires the rotational phase of the planting claw 22 at the rising timing of the soil reaction force. More specifically, as shown in FIG. 5B, the control unit outputs a pulse from the bottom dead center detection unit when the soil reaction force rises (when the tip of the planting claw 22 collides with the ground). The number of pulses output by the rotational phase detector (pickup sensor) until the tip of the planting claw 22 reaches the bottom dead center is counted.

  Thereby, the phase difference Δθ between the point where the tip of the planting claw 22 collides with the ground and the bottom dead center can be acquired. Since the movement locus of the tip of the planting claw 22 is known, the depth (planting depth) at which the seedling is planted on the ground by the planting claw 22 can be calculated based on the phase difference Δθ. The depth of planting obtained as described above is the relative position of the bottom dead center of the planting claw 22 with respect to a certain point on the ground (more precisely, the point where the planting claw 22 has pierced the ground) (that is, below the ground). The distance to the dead point). Therefore, it can be said that the planting depth calculated | required as mentioned above shows the relative position (planting part position) of the planting part 3 with respect to a certain point on the ground.

  And a control part performs raising / lowering control of the planting part 3 using the planting depth value detected as mentioned above. Thereby, the followable | trackability of the planting part 3 with respect to the ground can be improved, and accurate raising / lowering control can be implement | achieved.

  In the conventional rice transplanter, the relative position of the planting part with respect to the ground (height of the planting part) can be detected with a certain degree of accuracy based on the rocking angle of the float. However, as described above, since the float contacts the ground in a wide range, the height of the planting portion that can be detected by the rocking angle of the float is averaged. Therefore, the height of the planting part cannot be accurately detected based on the rocking angle of the float.

  In this regard, according to the configuration of the present embodiment, the probe 29 pierces the ground at a certain point, so that the load cell 28 detects a reaction force from a certain point on the ground. Therefore, based on the detection result of the soil reaction force detection device 27 of the present embodiment, the relative position of the planting unit 3 with respect to a certain point on the ground can be detected. That is, unlike the float that contacts the ground over a large area, according to the configuration of the present embodiment, it is possible to detect the exact relative position (planting depth) of the planting unit 3 with respect to the ground. And since a planting part is controlled based on the planting depth obtained in this way, the planting part 3 can be made to track correctly with respect to the ground.

  Next, the control flow of the raising / lowering control in the rice transplanter 1 of this embodiment is demonstrated with reference to FIG.

  In step S <b> 101, the control unit monitors the detection waveform of the soil reaction force detection device 27. And, after the rising waveform of the soil reaction force when the planting claw 22 collides with the ground is detected, when the planting claw reaches the bottom dead center (that is, when planting of one seedling is finished), The planting depth value of the seedling is detected by the method described above (step S102). Thus, a planting depth value can be acquired every time a seedling is planted.

  Subsequently, the control unit determines the absolute value of the difference between the planting depth detection value and the target planting depth value set by the operator using the planting depth adjustment lever (that is, the planting depth detection value and the target planting value). It is determined whether or not the magnitude of the deviation exceeds a predetermined threshold (step S103). That is, if the difference (absolute value) is large, it can be determined that seedling planting abnormality has occurred because the seedling planting depth is too shallow or too deep. Therefore, when the difference exceeds a predetermined threshold, the control unit notifies the operator of an abnormality by sounding a buzzer sound (step S104). In the conventional rice transplanter, the operator has to visually confirm the planting abnormality, but according to the above configuration, the operator can recognize the planting abnormality in real time while planting the seedling. .

  Next, the control unit also adjusts the control gain of the lifting control. That is, if the detected value of the planting depth value is smaller than the target planting depth value (when the seedling planting depth is shallow), there is a possibility that problems such as floating seedlings may occur. Therefore, when the detected value of the planting depth value is smaller than the target planting depth value (determination in step S105), the control unit increases the control gain and shifts the elevation control to the sensitive side (step S106). Thereby, the followable | trackability with respect to the ground of the planting part 3 improves, and it can prevent a floating seedling.

  And a control part performs raising / lowering control based on the detected planting depth value (step S109). That is, when the detected planting depth value is smaller than the target planting depth value set by the operator using the planting depth adjustment lever (when planting is shallow), the control unit drives the lifting cylinder 14 to plant the planting unit 3. Is lowered. On the other hand, when the detected planting depth value is larger than the target planting depth value (when planting is deep), the control unit drives the elevating cylinder 14 to raise the planting unit 3. The above control can be realized by known PID control or the like. Thereby, seedlings can be planted at a desired planting depth. Further, as described above, since the control gain of the elevation control is adjusted based on the detected planting depth value, it is possible to perform control while preventing the problem of floating seedlings.

  In addition, as mentioned above, the conventional rice transplanter controlled the raising / lowering of the planting part based on the rocking angle of the float. However, the lifting control based on the rocking angle of the float is difficult to keep the planting depth constant due to the influence of soil conditions (such as soil hardness). This is because the seedling planting depth (planting depth) varies depending on soil conditions. In this respect, the rice transplanter 1 of the present embodiment can directly detect the planting depth value by the above-described soil reaction force detection device 27. And since planting part 3 is raised / lowered controlled based on the planting depth value detected in this way, even if soil conditions change, planting depth value can be kept constant. Therefore, unlike the conventional rice transplanter, it is not necessary for the operator to finely adjust the setting according to the soil conditions.

  Moreover, since the rice transplanter 1 of this embodiment can raise / lower a planting part based on the detected planting depth value, it detects the float with which the conventional rice transplanter was equipped, and the rocking | fluctuation angle of the float. For this reason, a float sensor or the like is omitted. Thereby, the rice transplanter 1 can be comprised simply.

  When the process of step S109 ends, the process returns to step S101 and continues control. If the planting work has been completed (determined in step S110), the flow is terminated because there is no need to continue the elevation control.

  In addition, if the raising / lowering control of the planting part 3 is performed too sensitively, there is a problem that hunting is likely to occur. For this reason, it is preferable from the viewpoint of hunting prevention that the above-mentioned lifting control is not performed excessively sensitively in a situation where it is not necessary to perform the lifting control sensitively (for example, a situation where there is a low possibility of floating seedlings). Therefore, in this embodiment, in a situation where there is little risk of floating seedlings, the lifting control is configured to shift to the insensitive side.

  Specifically, the control unit determines whether or not the detection value of the planting depth value is larger than the target planting depth value in the determination of step S107. When the detection value of the planting depth value is larger than the target planting depth value, there is no concern about floating seedlings. Therefore, when it is determined in step S107 that the detection value of the planting depth value is larger than the target planting depth value, the control unit decreases the control gain and shifts the elevation control to the insensitive side (step S108). Thereby, since raising / lowering control is not performed too sensitively, hunting etc. can be prevented.

  As described above, the rice transplanter 1 according to the present embodiment includes the soil reaction force detection device 27 and the control unit. The planting unit 3 plants the seedlings by driving the planting claws 22. The soil reaction force detection device 27 is for detecting a planting depth indicating a relative position of the planting unit 3 with respect to a certain point on the ground. And a control part raises / lowers the planting part 3 based on the detected planting depth value.

  In this way, by performing the elevation control of the planting unit 3 based on the relative position of the planting unit with respect to a certain point on the ground, the planting unit can be accurately followed with respect to the ground. Seedlings can be planted deep.

  Moreover, in the rice transplanter 1 of this embodiment, the soil reaction force detection device 27 includes a soil reaction force detection unit that detects a soil reaction force received from the soil every time the planting claw 22 performs planting of a seedling, and a planting claw. A rotation phase detection unit that detects a rotation phase is provided, and the control unit calculates a planting depth based on the soil reaction force and the rotation phase (step S102).

  Thus, by detecting the soil reaction force generated in the planting claw 22, it becomes possible to acquire the planting depth value in real time, so that stable and accurate planting can be performed.

  Moreover, in the rice transplanter of this embodiment, the said control part compares the detected planting depth value with the target value of the planting depth, and performs the sensitivity adjustment of the said raising / lowering control (step S105 to S108).

  Thereby, the sensitivity adjustment which was conventionally performed manually for each field condition can be automatically performed.

  Moreover, in the rice transplanter of this form, the said control part is alert | reported that abnormality has arisen, when the difference of the detected value of a planting depth value and a target value has exceeded the predetermined threshold value (step S103, S104).

  Thereby, an operator can recognize planting abnormality in real time.

  Next, a second embodiment of the present invention will be described. In the following description, the same or similar components as those in the above embodiment are denoted by the same reference numerals as those in the first embodiment, and the description thereof is omitted.

  In the rice transplanter of this embodiment, the soil reaction force detection device is configured as a strain gauge 271. As shown in FIG. 7, the strain gauge 271 is directly attached to the planting claw 22. That is, by attaching a strain gauge 271 to the planting claw 22 and detecting the strain generated in the planting claw 22 with the strain gauge, the soil reaction force received by the planting claw 22 from the ground is directly detected. can do. Since the strain gauge is small and light, there is little risk of hindering the planting operation by the planting claws 22.

  In the said 1st Embodiment, the planting depth value based on a soil reaction force demonstrated that the planting nail | claw 22 was acquired whenever a seedling is planted. In other words, the planting depth value calculated based on the soil reaction force can be obtained only discretely. Therefore, when performing raising / lowering control of a planting part using a planting depth value like 1st Embodiment, the said raising / lowering control may generate | occur | produce a delay.

  In this regard, the conventional rice transplanter detects the swing angle of the float using a float sensor, and performs lift control based on the swing angle. The float swing angle can be detected continuously. However, as described above, in the lifting control based on the rocking angle of the float, it has been difficult to control the planting depth value to be kept constant.

  Therefore, in this embodiment, the planting depth value and the rocking angle of the float are used in a complementary manner, so that control delay can be prevented and the planting depth can be kept constant. This will be specifically described below.

  As shown in FIG. 7, the rice transplanter of the present embodiment includes a float 16 and a float sensor 34 in addition to the soil reaction force detection device 271. The structures of the float 16 and the float sensor 34 are the same as those of a conventional rice transplanter, but will be described briefly.

  The float 16 is provided below each of the three planting bevel cases 24. The float 16 is arranged so that its lower surface can contact the ground. Thereby, the ground can be leveled and planting can be performed cleanly.

  The float 16 is configured to be rotatable about a swing fulcrum 32. The float 16 is biased downward by the pressing member 33 at a position in front of the swing fulcrum 32. That is, a force is applied so that the front end portion of the float 16 is pressed against the ground. Since it is comprised in this way, the float 16 becomes an attitude | position of front-lowering, so that the planting part 3 leaves | separates from the ground. That is, the angle of the float 16 changes according to the height of the planting part 3 (distance from the ground).

  In a side view, the distance from the bottom surface (floating surface) of the float 16 to the bottom dead center of the planting claw 22 is referred to as the nail protrusion amount. The amount of nail removal is one of the important parameters that affects the planting depth of seedlings. The rice transplanter 1 according to the present embodiment includes a nail amount lever for an operator to adjust the nail amount. By adjusting the protrusion amount lever, the swing fulcrum 32 of the float can be moved up and down. Thereby, the amount of nail protrusion can be changed. Further, the amount of nail protrusion also varies depending on the angle of the float 16. Therefore, the amount of nail protrusion can be adjusted by adjusting the height of the planting part 3.

  At least one of the plurality of floats 16 is provided with a float sensor 34 that detects a swing angle (float angle) of the float 16. The float sensor 34 is configured as a potentiometer, for example. The detection value of the float sensor 34 is output to the control unit.

  Moreover, the rice transplanter 1 of this embodiment is comprised so that the force (henceforth a sensing load) which presses the float 16 with respect to the ground with the said press member 33 can be adjusted.

  Next, the flow of the raising / lowering control in the rice transplanter of this embodiment is demonstrated with reference to FIG.

  In this embodiment, a control part performs the raising / lowering control of the planting part 3 with reference to the float angle which the float sensor 34 detected (step S201). That is, when the detected value of the float angle is rising forward compared to the target value, it means that the planting unit 3 is too low with respect to the ground, and therefore the control unit raises the planting unit 3. On the other hand, when the detected value of the float angle is lower than the target value, the planting unit 3 is too high with respect to the ground, and therefore the control unit lowers the planting unit 3. This control can be realized by known PID control.

  In the first embodiment, since the raising / lowering control is performed based on the planting depth value acquired every time a seedling is planted, the control cannot be performed at a period earlier than the seedling planting period. It was. In this respect, since the output of the float sensor 34 can be obtained continuously, the control cycle of the lifting control can be shortened, and the control delay can be minimized.

  However, as described above, the lifting control based only on the float angle cannot plant seedlings at a desired planting depth. Therefore, in the rice transplanter of the present embodiment, the control unit is configured to change the target value, control gain, and the like of the lifting control based on the planting depth value calculated from the detection result of the soil reaction force detection device 271. .

  The controller monitors the detection waveform of the soil reaction force detection device 271 during the elevation control with reference to the float angle. When the planting claw 22 finishes planting one seedling (determined by the determination in step S202), a planting depth value is acquired based on the soil reaction force output by the soil reaction force detection device 271 (step S203). When the control unit acquires a new planting depth value, the control unit proceeds to the processing after step S204.

  In the rice transplanter 1 according to the present embodiment, when a planting depth value is newly acquired, the control unit determines whether the planting depth value or the amplitude of the float angle exceeds a threshold value (step S204). Hunting may have occurred if the planting depth value or float angle fluctuated greatly. Therefore, when the planting depth value or the amplitude of the float angle exceeds the threshold value, the control unit lowers the control gain and shifts the elevation control to the insensitive side (step S205). Thereby, since the planting part 3 is not moved up and down sensitively, hunting can be prevented.

  Next, the control unit adjusts the target value of the float angle and the control gain. That is, when the planting depth value calculated by the control unit is smaller than the target planting depth value set by the operator using the planting depth adjustment lever (when planting is too shallow, determination is made in step S206), the control unit displays the float angle. The target value is changed to the front rising side (step S207). Thereby, since the position of the planting part 3 falls and it comes to be controlled by the mood, the planting depth becomes deep.

  On the other hand, when the planting depth value calculated by the control unit is larger than the target planting depth value (when planting is too deep, determination is made in step S208), the control unit moves the target value of the float angle toward the front lowering side. Change (step S209). Thereby, since the position of the planting part 3 goes up and it comes to be controlled by the mood, a planting depth becomes shallow.

  When the above process is completed, the process returns to step S201 to continue the control. Note that if the planting work has been completed (determined in step S210), the flow is terminated because there is no need to continue the elevation control.

  Moreover, in the rice transplanter 1 of this embodiment, the control part is adjusting the control gain according to the load which arises in the planting nail | claw 22 in parallel with the process from said step S203 to S209.

  That is, when the planting claw 22 finishes planting one seedling (determined by the determination in step S202), the control unit calculates a load generated on the planting claw 22 during planting (step S211). In this embodiment, since it is comprised so that the soil reaction force produced in the planting nail | claw 22 may be detected directly with the soil reaction force detection apparatus 27 comprised as a strain gauge, based on the said soil reaction force The load can be detected directly.

  Next, the control unit determines whether or not the load exceeds a threshold value (step S212). When an excessively large load is applied to the planting claw 22, the planting part 3 is in a state in which the ascending / descending speed is excessively high and the planting claw 22 is under a load. Therefore, when the load applied to the planting claw 22 exceeds the threshold value, the control unit reduces the control gain and suppresses the lifting speed of the planting unit 3 (step S213). On the other hand, if the load is less than or equal to the threshold value, the control gain is increased to improve the follow-up performance of the lifting control (step S214).

  In the above, the structure which acquires the planting depth value based on the soil reaction force, and corrects the control gain and target angle of the raising / lowering control using the float angle based on the planting depth value has been described. In addition to this, the rice transplanter 1 of this embodiment is configured to adjust the sensing load and the amount of nail protrusion based on the planting depth value.

  For example, when it is determined in step S206 that the planting is too shallow, the control unit lowers the planting unit 3 to increase the nail extraction amount. Conversely, when it is determined in step S208 that the planting is too deep, the control unit raises the planting unit 3 to reduce the nail sticking amount. Thereby, planting can be performed at a desired planting depth.

  Moreover, the rice transplanter 1 of this embodiment is also configured to acquire information on soil hardness, impurities in the soil, and the like based on the soil reaction force, and to perform lifting control based on these information.

  For example, the harder the soil, the greater the force that the planting claw 22 receives from the soil. Accordingly, the soil hardness can be calculated based on the magnitude of the soil reaction force when the planting claw 22 collides with the soil. When the soil hardness is high (when the field is hard), the control unit performs adjustment so as to increase the sensing load. Thereby, a float can be strongly pressed with respect to the ground, and the ground can be leveled appropriately. On the other hand, when the soil hardness is low (when the field is soft), the control unit performs adjustment so as to decrease the sensing load. Thereby, it can prevent that the trace of a float remains on the ground.

  Further, the control unit is configured to detect contaminants in the soil (for example, a lump of stone) based on the detected change in the soil reaction force. That is, when there is no contaminant in the soil, the output waveform output by the soil reaction force detection device 27 is as shown in FIG. However, if there are contaminants in the soil, a unique waveform is shown such that the soil reaction force suddenly increases in the middle of this output waveform. Therefore, the control unit is configured to detect impurities in the soil when the soil reaction force suddenly increases in the middle based on the rate of change of the detection waveform of the soil reaction force detection device 27. . The control unit appropriately adjusts the control gain and the like according to the presence / absence of impurities and the type of impurities.

  As described above, when the planting claw 22 is pulled out from the ground, a negative reaction force is generated due to the adhesive force of the soil. Therefore, the control unit is configured to calculate the adhesive force of the soil based on the soil reaction force when the planting claw 22 is pulled out from the ground. The control unit corrects the float target angle to rise front or fall according to the calculated adhesive force. Thereby, planting can be performed according to the adhesive force of soil.

  The detection value of the float sensor 34 is affected by the pitching of the vehicle body. Therefore, the rice transplanter of this embodiment includes an inclination sensor that detects the pitching angle of the vehicle body, and is configured to correct the float target angle based on the detected pitching angle. Thereby, exact raising / lowering control is attained.

  As described above, according to the soil reaction force detection device 271 included in the rice transplanter 1 according to the present embodiment, in addition to the seedling planting depth value, soil hardness, presence / absence of impurities in the soil, soil adhesion, and the like are detected. be able to. However, these pieces of information can be obtained in the same manner using the detection results of the load cell type soil reaction force detection device 27 provided in the rice transplanter 1 of the first embodiment. These are information that could not be obtained in real time while the rice transplanter was traveling. According to the structure of this invention, whenever the planting nail | planting 22 plants a seedling, the said information can be acquired and it can utilize for raising / lowering control. Moreover, the rice transplanter 1 is provided with the display part for displaying the information acquired as mentioned above. Thereby, since the operator can refer in real time to the various information which the control part calculated, it can perform planting work appropriately.

  As described above, the rice transplanter of the present embodiment includes the float 16 that is swingably attached to the planting unit 3 and that can contact the ground.

  This float 16 makes it possible to level the soil and can be planted well.

  Moreover, the rice transplanter 1 of this embodiment includes a float sensor 34 that detects the swing angle of the float 16. And a control part raises / lowers the planting part 3 based on the planting depth value and the output value of the float sensor 34. FIG.

  That is, since the planting depth value can be obtained only when the planting claw 22 has planted a seedling, it becomes discrete information. Therefore, problems such as control delay can be avoided by using the output of the float sensor 34 that can obtain information continuously.

  Moreover, in the rice transplanter 1 of this embodiment, the control part adjusts the target value of a float angle based on the result of having compared the detected planting depth value and the planting depth target value (step S207, S209).

  Thereby, since the raising / lowering control by the float angle which is easy to be influenced by the field condition can be corrected by the planting depth value, continuous and stable planting work is possible. Therefore, high robustness can be realized. Further, it is not necessary to manually adjust the float target angle according to the field conditions.

  Moreover, in the rice transplanter 1 of this embodiment, the control part performs the gain adjustment of the raising / lowering control using a float angle based on the detected value of the soil reaction force detection apparatus 27 (step S213, S214).

  As described above, by correcting the control gain of the lifting control using the float angle based on the detection value of the soil reaction force detection device 27, a more stable planting operation can be performed.

  In the rice transplanter of the present embodiment, the control unit adjusts the nail protrusion amount, the sensing load, and the like based on the detected planting depth value.

  Thus, by adjusting various items for controlling the rice transplanter based on the detected planting depth value, the planting operation can be performed with higher accuracy.

  Moreover, in the rice transplanter of this embodiment, the control part makes the control gain of raising / lowering control small, when the detected float angle or the amplitude of the detected planting depth value exceeds a predetermined threshold value.

  Thereby, it is possible to deal with problems such as hunting in real time.

  Further, in the rice transplanter of the present embodiment, the control unit acquires soil hardness, soil adhesive force, and pitching information, and accordingly, control gain, float target angle, float pressing load, nail protrusion amount, etc. The items are adjusted.

  In this way, by adjusting various items for controlling the rice transplanter based on information such as soil hardness, soil adhesion, and pitching information, planting work more accurately suited to the field conditions can be performed. It becomes possible.

  Although the preferred embodiments of the present invention have been described above, the above configuration can be modified as follows.

  In the said embodiment, the planting depth (planting depth) of a seedling is acquired as information which shows the relative position of the planting part with respect to one point with the ground. However, the present invention is not limited to this, and if the relative position of the planting part with respect to a certain point on the ground is acquired in some form and the planting part can be lifted and lowered based on this, the same effect as the present invention can be obtained. .

  For example, it can replace with planting depth and can comprise so that the distance from the lower end of seedling mounting stand 17 to one point of the ground may be acquired. By controlling the raising and lowering of the planting unit 3 based on the information on the position of the seedling platform 17 obtained in this way, the height of the seedling platform 17 with respect to the ground can be accurately maintained. Accurate planting with a constant depth can be performed.

  The configuration of the planting portion position acquisition means is not limited to the above, and any configuration may be used as long as the relative position of the planting portion with respect to a certain point on the ground can be detected. However, like the soil reaction force detection device of the above embodiment, a member (probe or planting claw in the above embodiment) that can contact a certain point on the ground is provided in the planting portion, and the tip of the member is the ground If it is configured to detect that it has touched, the relative position of the planting part with respect to a certain point on the ground can be detected with a simple configuration.

  The configuration of the soil reaction force detection device is not limited to the above, and any configuration that can detect the force that the planting claw 22 receives from the soil may be used.

  Furthermore, the soil reaction force detection device does not necessarily have to be configured to rotate integrally with the planting claw. For example, apart from the planting claw, a rotating body that is rotationally driven is provided, and a rushing body that enters the ground while drawing a predetermined loop-like trajectory by rotating together with the rotating body is provided. The soil reaction force can be detected by detecting the reaction force generated in the rush body. Moreover, if it comprises so that the rotational phase of this rushing body may be detected, the function equivalent to the soil reaction force detection apparatus of the said embodiment is realizable.

  In the drawing, the soil reaction force detection device is attached to only one of the two planting claws 22 included in the planting unit 20, but the soil reaction force detection device may be attached to both planting claws 22. In this case, since the information on the soil reaction force can be acquired at twice the density, the control can be performed more finely.

  In the above description, the soil reaction force detection device is disposed in the planting unit near the center in the left-right direction. However, the present invention is not limited thereto, and the soil reaction force detection device may be disposed in any planting unit. Further, the soil reaction force detection device may be arranged in any one of a plurality of planting units, or may be arranged in all the planting units 20.

  The setting operation tool for setting the target planting depth is not limited to the lever. For example, the target planting depth may be set by a dial-shaped member.

  In the above embodiment, the rotational phase detection unit and the bottom dead center detection unit are arranged in the planting bevel case. However, the rotational phase detection unit and the bottom dead center detection unit are arranged anywhere in the driving transmission path from the driving source to the planting claw. Also good. For example, the rotational phase detector can be arranged in the planting center case.

DESCRIPTION OF SYMBOLS 1 Rice transplanter 3 Planting part 21 Rotating case 22 Planting claw 27 Soil reaction force detection apparatus (planting part position acquisition means)

Claims (8)

Planting part position acquisition means for detecting a planting part position indicating a relative position of the planting part with respect to a certain point on the ground;
Based on the detected planting part position, a control unit for raising and lowering the planting part,
Rice transplanter characterized by comprising. The rice transplanter according to claim 1,
The planting part position acquisition means includes:
A soil reaction force detection unit that detects a soil reaction force that the planting unit receives from the soil every time the planting claw provided in the planting unit performs seedling planting,
A phase detector for detecting the rotational phase of the planting claw;
Consists of
The said control part detects the said planting part position based on the said soil reaction force and a rotation phase, The rice transplanter characterized by the above-mentioned. The rice transplanter according to claim 1 or 2,
The said control part compares the detected value of the said planting part position, and the target value of a planting part position, and performs the sensitivity adjustment of the said raising / lowering control, The rice transplanter characterized by the above-mentioned. A rice transplanter according to any one of claims 1 to 3,
The rice transplanter according to claim 1, wherein the controller notifies the occurrence of an abnormality when a difference between a detected value of the planting part position and a target value of the planting part position exceeds a predetermined threshold value. A rice transplanter according to any one of claims 1 to 4,
A float that is swingably attached to the planting part and that can contact the ground,
A float sensor for detecting a swing angle of the float;
With
The said control part raises / lowers the said planting part based on the detected value of the said planting part position, and the output value of the said float sensor, The rice transplanter characterized by the above-mentioned. The rice transplanter according to claim 5,
The control unit adjusts the target value of the rocking angle of the float based on the result of comparing the detected value of the planting part position and the target value of the planting part position. Machine. The rice transplanter according to claim 5 or 6,
The said control part performs the gain adjustment of the raising / lowering control using the rocking | fluctuation angle of the said float based on the detected value of the said planting part position, The rice transplanter characterized by the above-mentioned. A rice transplanter according to any one of claims 5 to 7,
The control unit adjusts at least one of the amount of planting claw protruding from the surface of the float surface and the pressing load of the float against the ground based on the detected value of the planting unit position. Rice transplanter characterized by.

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